阅读说明：本技术 静电图像显影用调色剂 (Toner for developing electrostatic image ) 是由 柳生左京 于 2019-08-30 设计创作，主要内容包括：本发明提供一种静电图像显影用调色剂,含有包含粘结树脂、着色剂、带电控制剂、离型剂以及具有聚二烯结构的添加剂的着色树脂颗粒,上述具有聚二烯结构的添加剂在温度40℃的苯乙烯中的溶解度为3～40g/100g,在通过透射型电子显微镜(TEM)观察上述着色树脂颗粒的截面的情况下,在上述着色树脂颗粒的截面的2μm×2μm见方的视野中,长宽比在2～10的范围的离型剂的晶畴的存在个数为2～30个。(The invention provides a toner for developing electrostatic images, which contains colored resin particles containing a binder resin, a colorant, a charge control agent, a release agent and an additive having a polydiene structure, wherein the additive having a polydiene structure has a solubility in styrene at 40 ℃ of 3 to 40g/100g, and when the cross section of the colored resin particles is observed by a Transmission Electron Microscope (TEM), the number of crystal domains of the release agent having an aspect ratio in the range of 2 to 10 is 2 to 30 in a field of view of 2 [ mu ] m × 2 [ mu ] m of the cross section of the colored resin particles.)

1. A toner for developing an electrostatic image, comprising colored resin particles containing a binder resin, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure,

the solubility of the additive with the polydiene structure in styrene at the temperature of 40 ℃ is 3-40 g/100g,

when the cross section of the colored resin particles is observed by a Transmission Electron Microscope (TEM), the number of the crystal domains of the mold release agent with the aspect ratio within the range of 2-10 is 2-30 in a field of view of 2 [ mu ] m × 2 [ mu ] m square of the cross section of the colored resin particles.

2. A toner for developing an electrostatic image, comprising colored resin particles containing a binder resin, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure,

the solubility of the additive with the polydiene structure in styrene at the temperature of 40 ℃ is 3-40 g/100g,

the colored tree is obtained by dynamic viscoelasticity measurementThe storage modulus G' (60) of the lipid particles at 60 ℃ is 1.6X 10⁸～5.0×10⁸Pa。

3. The electrostatic image developing toner according to claim 1, wherein the storage modulus G' (60) of the colored resin particles at 60 ℃ determined by dynamic viscoelasticity measurement is 1.6 x 10⁸～5.0×10⁸Pa。

4. The toner for developing electrostatic images according to claim 2 or 3, wherein the storage modulus G' (100) of the colored resin particles at 100 ℃ determined by dynamic viscoelasticity measurement is 1.0 x 10⁵～3.0×10⁵Pa。

5. The toner for developing electrostatic images according to any one of claims 2 to 4, wherein a ratio G '(60)/G' (100) of a storage modulus G '(60) at 60 ℃ and a storage modulus G' (100) at 100 ℃ of the colored resin particles, which is determined by dynamic viscoelasticity measurement, is 1.0 x 10³～5.0×10³。

6. The electrostatic image developing toner according to any one of claims 1 to 5, wherein the additive having a polydiene structure is a conjugated diene-aromatic vinyl thermoplastic elastomer.

7. The electrostatic image developing toner according to claim 6, wherein the conjugated diene-aromatic vinyl thermoplastic elastomer contains a diblock copolymer composed of an aromatic vinyl polymer block and a block of a polymer copolymerizable with the aromatic vinyl polymer at a ratio of 40% by mass or more.

8. The electrostatic image developing toner according to claim 7, wherein a content ratio of the aromatic vinyl monomer units in the conjugated diene-aromatic vinyl thermoplastic elastomer is 10 to 30% by mass with respect to all monomer units.

9. The electrostatic image developing toner according to any one of claims 1 to 8, wherein the content of the additive having a polydiene structure is 1 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

10. The electrostatic image developing toner according to any one of claims 1 to 9, wherein the release agent is a fatty acid ester compound having a number average molecular weight (Mn) of 500 to 1500.

Technical Field

The present invention relates to an electrostatic image developing toner for developing an electrostatic latent image in electrophotography, electrostatic recording method, electrostatic printing method, or the like.

Background

In image forming apparatuses such as electrophotographic apparatuses, electrostatic recording apparatuses, and electrostatic printing apparatuses, a method of forming a desired image by developing an electrostatic latent image formed on a photoreceptor with an electrostatic image developing toner has been widely performed, and the method is applied to copying machines, printers, facsimile machines, and complex machines thereof.

For example, in an electrophotographic apparatus using an electrophotographic method, generally, a surface of a photoreceptor formed of a photoconductive substance is uniformly charged by various methods, an electrostatic latent image is formed on the photoreceptor, the electrostatic latent image is developed with a toner (developing step), the toner image is transferred to a recording material such as paper as required (transfer step), and then the toner is fixed to the recording material by heating or the like (fixing step) to obtain a printed matter.

In the image forming process, particularly in the fixing process, it is generally necessary to heat the fixing roller to 150 ℃ or higher at the time of fixing, and much power as an energy source is consumed. In contrast, in recent years, with the increasing demand for reduction in energy consumption and increase in printing speed of the image forming apparatus, it has been required to design a toner (toner having excellent low-temperature fixability) capable of maintaining a high fixing ratio even at a low fixing temperature.

In response to the above-mentioned demand, there have been proposed a method of lowering the glass transition temperature (Tg) of a toner, a method of containing a low-melting resin and/or a low-molecular-weight resin in the toner, a method of containing a low-softening-point substance (releasing agent) having releasing property (releasability) such as wax in the toner, and the like.

However, in the case of improving the low-temperature fixability, although the temperature of the fixing roller can be set low at the time of fixing, on the other hand, when the toner is used at a high temperature or left (stored) for a long period of time, fusion (blocking (aggregation) of toner particles is likely to occur, and the storage stability of the toner is sometimes lowered. Therefore, in designing a toner, it is necessary to consider storage stability, which is a characteristic contrary to low-temperature fixability, and to develop a toner which can improve low-temperature fixability without impairing storage stability and can reduce power consumption.

For example, patent document 1 discloses a black toner including toner particles containing a binder resin, a crystalline material, and a black colorant, wherein, in a cross section of the toner particles observed by a transmission electron microscope, when a long diameter of the cross section of the toner particles is R (μm) and a long diameter of a domain of the crystalline material is R (μm), R (μm) satisfies 4 ≦ R ≦ 12, and a domain of the crystalline material satisfying the following formula (i) is defined as a domain a, the number of the domains a per cross section of the toner particles is 20 or more and 300 or less.

(i)5.0×10^-4≤r/R≤7.0×10^-2

According to the technique of patent document 1, the entire resin is plasticized by melting the crystal domains a at the time of thermal fixing, and further, the crystalline material constituting the crystal domains a bleeds out on the surface of the toner particles to improve the fixing property and to exhibit the releasing property from a fixing member such as a fixing film.

Further, patent document 2 discloses a toner having toner particles containing a binder resin and a colorant, characterized in that the toner has a storage modulus (G' 60) of 1.0 × 10 at a temperature of 60 ℃ in viscoelasticity characteristics measured at a frequency of 6.28rad/sec using a rotary flat plate rheometer⁷～1.0×10⁹(Pa) having a maximum storage modulus (G' p) of 5.0X 10 at a temperature of 110 ℃ to 140 DEG C⁴～5.0×10⁶(Pa)。

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2019-12188;

patent document 2: japanese patent laid-open No. 2012 and 177914.

Disclosure of Invention

Problems to be solved by the invention

On the other hand, in the technique of patent document 1, although the fixability such as low-temperature fixability is improved, the storage stability is not sufficient, and therefore, further improvement is required.

Further, the technique of patent document 2 is a technique in which a polyester resin is used as a binder resin, and the technique of patent document 2 has a problem in that low-temperature fixability is insufficient.

The invention aims to provide a toner for developing electrostatic images, which has excellent storage stability and low-temperature fixing performance.

Means for solving the problems

As a result of studies to achieve the above object, the present inventors have found that the above problems can be solved by controlling the number of domains of a release agent having an aspect ratio in the range of 2 to 10 in colored resin particles to a predetermined range, while containing an additive having a polydiene structure and having a solubility in styrene at 40 ℃ of 3 to 40g/100g as an additive in the colored resin particles, in a toner for developing electrostatic images containing the colored resin particles containing a binder resin, a colorant, a charge control agent, and a release agent, and have completed the present invention.

Further, the present inventors have further studied and found that, in an electrostatic image developing toner containing colored resin particles comprising a binder resin, a colorant, a charge control agent and a release agent, an additive having a polydiene structure and having a solubility in styrene at a temperature of 40 ℃ of 3 to 40G/100G is contained in the colored resin particles as an additive, and a storage modulus G' (60) of the colored resin particles at 60 ℃ determined by dynamic viscoelasticity measurement is controlled to be 1.6 × 10⁸～5.0×10⁸The range of Pa, the above problem can be solved.

That is, according to the present invention, there is provided an electrostatic image developing toner according to claim 1, which contains colored resin particles containing a binder resin, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure,

the solubility of the additive with a polydiene structure in styrene at a temperature of 40 ℃ is 3-40 g/100g,

when the cross section of the colored resin particles is observed by a Transmission Electron Microscope (TEM), the number of the crystal domains of the mold release agent with the aspect ratio in the range of 2-10 is 2-30 in a visual field of 2 μm multiplied by 2 μm square of the cross section of the colored resin particles.

Alternatively, according to the present invention, as the toner for developing an electrostatic image according to claim 2, there is provided a toner for developing an electrostatic image, which contains colored resin particles containing a binder resin, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure,

the solubility of the additive with a polydiene structure in styrene at a temperature of 40 ℃ is 3-40 g/100g,

the storage modulus G' (60) of the colored resin particles at 60 ℃ determined by dynamic viscoelasticity measurement is 1.6X 10⁸～5.0×10⁸Pa。

In the toner for developing electrostatic images according to claim 2 of the present invention, it is preferable that the storage modulus G' (100) of the colored resin particles at 100 ℃ determined by dynamic viscoelasticity measurement is 1.0 × 10⁵～3.0×10⁵Pa。

In the toner for developing an electrostatic image according to aspect 2 of the present invention, it is preferable that a ratio G '(60)/G' (100) of a storage modulus G '(60) at 60 ℃ to a storage modulus G' (100) at 100 ℃ of the colored resin particles determined by dynamic viscoelasticity measurement is 1.0 × 10³～5.0×10³。

In the electrostatic image developing toner of the present invention, the additive having a polydiene structure is preferably an aromatic vinyl thermoplastic elastomer.

Alternatively, in the toner for developing an electrostatic image of the present invention, it is preferable that the conjugated diene-aromatic vinyl thermoplastic elastomer contains a diblock copolymer composed of an aromatic vinyl polymer block and a block of a polymer copolymerizable with the aromatic vinyl polymer at a ratio of 40% by mass or more.

In the toner for developing an electrostatic image of the present invention, the content ratio of the aromatic vinyl monomer unit in the conjugated diene-aromatic vinyl thermoplastic elastomer is preferably 10 to 30% by mass with respect to the total monomer units.

In the toner for developing an electrostatic image according to the present invention, the content of the additive having a polydiene structure is preferably 1 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

Further, in the toner for developing an electrostatic image according to the present invention, the release agent is preferably a fatty acid ester compound having a number average molecular weight (Mn) of 500 to 1500.

Effects of the invention

According to the present invention, a toner for developing an electrostatic image having excellent storage stability and low-temperature fixability can be provided.

Drawings

FIG. 1(A) is a photograph of a cross section of the colored resin particles in example 1-1 taken by a Transmission Electron Microscope (TEM), and FIG. 1(B) is a photograph of a cross section of the colored resin particles in comparative example 1-1 taken by a Transmission Electron Microscope (TEM).

Detailed Description

< toner for developing Electrostatic image according to claim 1 >

The electrostatic image developing toner according to claim 1 of the present invention (hereinafter, may be simply referred to as "toner") contains colored resin particles containing a binder resin, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure,

the solubility of the additive with a polydiene structure in styrene at a temperature of 40 ℃ is 3-40 g/100g,

when the cross section of the colored resin particles is observed by a Transmission Electron Microscope (TEM), the number of crystal domains of the mold release agent with the aspect ratio in the range of 2-10 is in the range of 2-30 in a field of view of 2 [ mu ] m × 2 [ mu ] m square of the cross section of the colored resin particles.

First, a method for producing colored resin particles constituting the toner according to claim 1 of the present invention will be described.

The method for producing colored resin particles constituting the toner according to aspect 1 of the present invention is roughly divided into: dry methods such as pulverization method; the emulsion polymerization aggregation method, dispersion polymerization method, suspension polymerization method, and dissolution suspension method are wet methods, and are preferred because toners having excellent printing characteristics such as image reproducibility can be easily obtained. In the wet process, since a toner having a small particle size distribution on the order of micrometers is easily obtained, polymerization methods such as an emulsion polymerization aggregation method, a dispersion polymerization method, and a suspension polymerization method are preferable, and among them, the suspension polymerization method is more preferable.

The emulsion polymerization coagulation method is as follows: the resin fine particles are obtained by polymerizing the emulsified polymerizable monomer, and the resin fine particles are aggregated with a colorant or the like to produce colored resin particles. In addition, the above dissolution suspension method is as follows: in the method of producing the colored resin particles, a solution obtained by dissolving or dispersing a toner component such as a binder resin or a colorant in an organic solvent is dropped into an aqueous medium to form droplets, and then the organic solvent is removed to produce the colored resin particles, and known methods can be used for each of the above methods.

The colored resin particles constituting the toner according to aspect 1 of the present invention can be produced by either a wet method or a dry method, and when the colored resin particles are produced by the suspension polymerization method (a), which is particularly preferable among the wet methods, or by the pulverization method (B), which is typical among the dry methods, the production is carried out by the following steps. First, the suspension polymerization method (a) will be explained.

(A) Suspension polymerization process

(A-1) Process for producing polymerizable monomer composition

In the suspension polymerization method, first, a polymerizable monomer, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure, and further, if necessary, other additives are mixed and dissolved to prepare a polymerizable monomer composition. The mixing in the preparation of the polymerizable monomer composition can be carried out using, for example, a medium-type dispersing machine.

In the present invention, the polymerizable monomer means a compound capable of polymerization, and the binder resin is formed by polymerizing the polymerizable monomer. As the polymerizable monomer, a monovinyl monomer is preferably used as a main component constituting the polymerizable monomer. Examples of the monovinyl monomer include: styrene monomers such as styrene, vinyl toluene, alpha-methylstyrene and ethylstyrene; (meth) acrylate monomers such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, dimethylaminoethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, and dimethylaminoethyl methacrylate; acrylic acid and methacrylic acid; nitrile compounds such as acrylonitrile and methacrylonitrile; amide compounds such as acrylamide and methacrylamide; olefins such as ethylene, propylene, butylene, and the like. These monovinylic monomers can be used either individually or in combination of two or more. Among them, styrene-based monomers and (meth) acrylate-based monomers are preferable, and styrene and butyl acrylate are more preferable. In addition, from the viewpoint of further improving the low-temperature fixing property of the obtained toner, it is preferable to use at least a styrene-based monomer and a (meth) acrylate-based monomer as the monovinyl monomer.

In the binder resin used in the present invention, the content ratio of the styrene monomer unit is preferably 60% by mass or more, more preferably 65% by mass or more, further preferably 68% by mass or more, and particularly preferably 70% by mass or more, and the upper limit is preferably 85% by mass or less, more preferably 80% by mass or less, further preferably 77% by mass or less, and particularly preferably 74% by mass or less. The content ratio of the (meth) acrylate monomer unit is preferably 20% by mass or more, more preferably 21% by mass or more, further preferably 21.5% by mass or more, further more preferably 22% by mass or more, particularly preferably 24% by mass or more, and the upper limit is preferably 40% by mass or less, more preferably 35% by mass or less, further preferably 32% by mass or less, further preferably 30% by mass or less, particularly preferably 28% by mass or less, and most preferably 26% by mass or less. When the content ratio of the styrene monomer unit and the (meth) acrylate monomer unit is in the above range, the obtained toner can have excellent storage stability and can further improve low-temperature fixability.

In the present invention, it is preferable to use a monovinyl monomer and use a polymerizable monomer having an arbitrary crosslinking property in order to improve thermal offset (hot offset) and storage stability. The crosslinkable polymerizable monomer is a monomer having 2 or more polymerizable functional groups. Examples of the crosslinkable polymerizable monomer include: aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, and derivatives thereof; ester compounds in which an alcohol having 2 or more hydroxyl groups such as ethylene glycol dimethacrylate and diethylene glycol dimethacrylate is ester-bonded to 2 or more carboxylic acids; other divinyl compounds such as N, N-divinylaniline and divinyl ether; compounds having 3 or more vinyl groups, and the like. These crosslinkable polymerizable monomers can be used alone or in combination of two or more. The amount of the crosslinkable polymerizable monomer used is preferably 0.1 to 5 parts by mass, more preferably 0.15 to 2 parts by mass, and still more preferably 0.2 to 0.7 part by mass, based on 100 parts by mass of the monovinyl monomer, and the content of the crosslinkable polymerizable monomer unit in the binder resin used in the present invention is preferably 0.1 to 5% by mass, more preferably 0.15 to 2% by mass, and still more preferably 0.2 to 0.7% by mass. When the amount and the content ratio of the crosslinkable polymerizable monomer are within the above ranges, the storage stability and the low-temperature fixability of the obtained toner can be further improved.

Further, when a macromonomer is used as a part of the polymerizable monomer, the storage stability and low-temperature fixing property of the obtained toner can be further improved, and therefore, it is preferable to use an arbitrary macromonomer. The macromonomer is a reactive oligomer or polymer having a polymerizable carbon-carbon unsaturated bond at the terminal of the molecular chain and having a number average molecular weight (Mn) of usually 1000 to 30000. The macromer preferably forms a polymer having a higher Tg (glass transition temperature) than the Tg of the polymer resulting from the macromer being unpolymerized. The amount of the macromonomer used is preferably 0.03 to 5 parts by mass, more preferably 0.05 to 1 part by mass, per 100 parts by mass of the monovinyl monomer.

In the present invention, a colorant is used, and when a color toner (4 kinds of toners, that is, black toner, cyan toner, yellow toner, and magenta toner, are generally used) is manufactured, a black colorant, a cyan colorant, a yellow colorant, and a magenta colorant can be used.

As the black colorant, for example, pigments and/or dyes such as carbon black, titanium black, and magnetic powders such as iron zinc oxide and iron nickel oxide can be used.

As the cyan colorant, compounds such as copper phthalocyanine pigments, derivatives thereof, and anthraquinone pigments and/or dyes can be used. Specific examples thereof include C.I. pigment blue 2,3, 6, 15: 1, 15: 2, 15: 3, 15: 4, 16, 17: 1, and 60.

As the yellow colorant, for example, compounds such as azo pigments such as monoazo pigments and disazo pigments, condensed polycyclic pigments, and/or dyes are used. Specifically, c.i. pigment yellow 3, 12, 13, 14, 15, 17, 62, 65, 73, 74, 83, 93, 97, 120, 138, 151, 155, 180, 181, 185, 186, 214, 219, c.i. solvent yellow 98, 162, and the like can be given.

As the magenta colorant, compounds such as azo pigments, fused polycyclic pigments and/or dyes, for example, monoazo pigments and disazo pigments, and the like can be used. Specifically, c.i. pigment red 31, 48, 57: 1, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 144, 146, 149, 150, 163, 170, 184, 185, 187, 202, 206, 207, 209, 251, c.i. solvent violet 31, 47, 59, c.i. pigment violet 19, and the like can be given.

In the present invention, each colorant may be used alone or in combination of two or more, and the amount of the colorant used is preferably 1 to 10 parts by mass per 100 parts by mass of the binder resin (100 parts by mass of the polymerizable monomer for obtaining the binder resin).

The charge control agent is not particularly limited as long as it is a charge control agent that is generally used as a charge control agent for toner, but among charge control agents, a positively chargeable or negatively chargeable charge control resin is preferable from the viewpoint of having high compatibility with a polymerizable monomer and being capable of imparting stable chargeability (charging stability) to toner particles, thereby improving dispersibility of a colorant, and further, a negatively chargeable charge control resin is more preferably used from the viewpoint of obtaining a negatively chargeable toner.

Examples of the positively chargeable charge control agent include nigrosine dyes, quaternary ammonium salts, triaminotriphenylmethane compounds, imidazole compounds, polyamine resins preferably used as charge control resins, quaternary ammonium group-containing copolymers, and the like.

Examples of the negatively chargeable charge control agent include: azo dyes containing metals such as Cr, Co, Al, and Fe; metal salicylate compounds and metal alkylsalicylate compounds; and sulfonic acid group-containing copolymers, carboxylic acid group-containing copolymers, and the like which are preferably used as the charge control resin.

The weight average molecular weight (Mw) of the charge control resin is in the range of 5000 to 30000, preferably 8000 to 25000, and more preferably 10000 to 20000 in terms of polystyrene as measured by Gel Permeation Chromatography (GPC) using tetrahydrofuran.

The copolymerization ratio of the monomer having a functional group such as a quaternary ammonium group or a sulfonate group in the charge control resin is preferably in the range of 0.5 to 12% by mass, more preferably in the range of 1.0 to 6% by mass, and still more preferably in the range of 1.5 to 3% by mass.

The content of the charge control agent is preferably 0.01 to 10 parts by mass, and more preferably 0.03 to 8 parts by mass, per 100 parts by mass of the binder resin (100 parts by mass of the polymerizable monomer for obtaining the binder resin). When the amount of the charge control agent added is in the above range, the occurrence of fogging and the occurrence of printing stain can be effectively suppressed, and the dispersibility of the colorant can be suitably improved.

The release agent is not particularly limited as long as it is a release agent generally used as a release agent for a toner, and from the viewpoint of suitably improving the low-temperature fixability of the obtained toner, a release agent having a number average molecular weight (Mn) of 500 to 1500 is preferable, and a fatty acid ester compound having a number average molecular weight (Mn) of 500 to 1500 is preferable. The term "fatty acid ester compound" refers to a product obtained by reacting an ester of a monohydric alcohol and/or a polyhydric alcohol with a saturated fatty acid and/or an unsaturated fatty acid.

Specific examples of the monohydric alcohol include: monohydric saturated aliphatic alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 1-hexanol, octanol, 2-ethyl-1-hexanol, nonanol, lauryl alcohol, cetyl alcohol, stearyl alcohol and behenyl alcohol; monohydric unsaturated aliphatic alcohols such as allyl alcohol, methallyl alcohol, crotyl alcohol, and oleyl alcohol; monohydric alicyclic alcohols such as cyclohexanol; monohydric aromatic alcohols such as phenol, benzyl alcohol (benzyl alcohol), methylphenol (cresol), p-ethylphenol, dimethylphenol (xylenol), nonylphenol, dodecylphenol, phenylphenol, and naphthol.

Specific examples of the polyol include: a binary saturated aliphatic alcohol such as ethylene glycol or propylene glycol; dihydric aromatic alcohols such as catechol and hydroquinone; and saturated aliphatic alcohols such as glycerol, pentaerythritol, dipentaerythritol, and polyglycerol.

Among these monohydric and polyhydric alcohols, the mono-to tetrahydric saturated aliphatic alcohols are preferable, stearyl alcohol, behenyl alcohol and pentaerythritol are more preferable, stearyl alcohol and behenyl alcohol are more preferable, and behenyl alcohol is particularly preferable.

The fatty acid used as a raw material of the fatty acid ester compound is preferably a saturated fatty acid and/or an unsaturated fatty acid having 12 to 22 carbon atoms, more preferably 14 to 18 carbon atoms. Among them, the saturated fatty acids having the above carbon number are particularly preferable because fatty acid ester compounds having a number average molecular weight (Mn) of 500 to 1500 can be easily obtained.

Specific examples of the saturated fatty acid having the above carbon number are not particularly limited, and lauric acid (carbon number 12), myristic acid (carbon number 14), pentadecanoic acid (carbon number 15), palmitic acid (carbon number 16), margaric acid (carbon number 17), stearic acid (carbon number 18), arachidic acid (carbon number 20), and behenic acid (carbon number 22), and the like can be given. Among these saturated fatty acids, stearic acid (having 18 carbon atoms), arachidic acid (having 20 carbon atoms) and behenic acid (having 22 carbon atoms) are preferable, and stearic acid (having 18 carbon atoms) is more preferable.

Specific examples of the unsaturated fatty acid are not particularly limited, and the following compounds may be mentioned.

Palmitoleic acid (CH)₃(CH₂)₅CH＝CH(CH₂)₇COOH)

Oleic acid (CH)₃(CH₂)₇CH＝CH(CH₂)₇COOH)

Isooleic acid (CH)₃(CH₂)₅CH＝CH(CH₂)₉COOH)

Linoleic acid (CH)₃(CH₂)₃(CH₂CH＝CH)₂(CH₂)₇COOH)

(9,12,15) -linolenic acid (CH)₃(CH₂CH＝CH)₃(CH₂)₇COOH)

(6,9,12) -linolenic acid (CH)₃(CH₂)₃(CH₂CH＝CH)₃(CH₂)₄COOH)

Eleostearic acid (CH)₃(CH₂)₃(CH＝CH)₃(CH₂)₇COOH)

Arachidonic acid (CH)₃(CH₂)₃(CH₂CH＝CH)₄(CH₂)₃COOH)

The saturated fatty acid and/or the unsaturated fatty acid may be used alone in an amount of 1 kind, or in combination of two or more kinds. Among the saturated fatty acids and unsaturated fatty acids, saturated fatty acids are preferable, stearic acid, arachidic acid, and behenic acid are more preferable, stearic acid and behenic acid are further preferable, and behenic acid is particularly preferable.

The fatty acid ester compound can be produced by a conventional method. Examples of the method for producing such a fatty acid ester compound include a method of carrying out an ester reaction using a monohydric alcohol and/or a polyhydric alcohol and a saturated fatty acid and/or an unsaturated fatty acid. Further, as the fatty acid ester compound, commercially available fatty acid ester compounds can be used, and examples of the commercially available fatty acid ester compounds include "WEP 2", "WEP 3", "WEP 4", "WEP 5", "WE 6" and "WE 11" (trade names mentioned above) manufactured by NOF Corporation.

In the present invention, the release agent other than the fatty acid ester compound may be used instead of or together with the fatty acid ester compound, and examples thereof include: low molecular weight polyolefin waxes, modified waxes thereof; vegetable-based natural waxes such as jojoba oil; petroleum waxes such as paraffin wax; mineral waxes such as ozokerite; synthetic waxes such as Fischer-Tropsch (Fischer-Tropsch) waxes; and polyhydric alcohol esters such as dipentaerythritol esters. These may be used alone in 1 kind, or two or more kinds may be used in combination.

The number average molecular weight (Mn) of the release agent is preferably 500 to 1500, more preferably 550 to 1200, and further preferably 550 to 1100. The number average molecular weight (Mn) of the release agent can be measured, for example, based on a polystyrene equivalent value measured by Gel Permeation Chromatography (GPC) using tetrahydrofuran.

The content of the release agent is preferably 1 to 30 parts by mass, more preferably 8 to 28 parts by mass, and still more preferably 12 to 25 parts by mass, per 100 parts by mass of the binder resin (100 parts by mass of the polymerizable monomer for obtaining the binder resin). When the content of the release agent is in the above range, the particle size distribution of the obtained toner can be relatively uniform, and the low-temperature fixability can be further improved.

In addition, in the present invention, the colored resin particles further contain an additive having a polydiene structure, the additive having a solubility in styrene at a temperature of 40 ℃ of 3 to 40g/100g or more. In the present invention, by using such an additive having a polydiene structure, the release agent can be finely dispersed in the colored resin particles in a state having a specific crystal domain structure by utilizing the compatibility of the additive having a polydiene structure with the release agent. Further, in the present invention, the release agent is finely dispersed in a state having a specific domain structure, whereby blocking of the obtained toner can be effectively suppressed, and the effect of improving low-temperature fixability by adding the release agent can be sufficiently exhibited, and as a result, the obtained toner can be made excellent in storage stability and low-temperature fixability.

The additive having a polydiene structure used in the present invention is not particularly limited as long as it has a polydiene structure (i.e., a structure derived from a diene compound) and has a solubility in styrene at 40 ℃ of 3 to 40g/100 g. The solubility of the additive having a polydiene structure in styrene at a temperature of 40 ℃ is preferably 5 to 30g/100g, and more preferably 10 to 25g/100 g. When the solubility in styrene at a temperature of 40 ℃ is too low, the dispersibility in the colored resin particles is lowered, whereby the compatibility with the release agent is lowered, and the release agent is insufficiently dispersed. As a result, the resulting toner has reduced low-temperature fixability and storage stability. On the other hand, if the solubility in styrene is too high, the binder resin in the colored resin particles is compatible with the release agent, and thus a crystal domain cannot be formed, and the low-temperature fixing property and storage stability of the toner deteriorate.

The additive having a polydiene structure used in the present invention is not particularly limited, and examples thereof include: a conjugated diene-aromatic vinyl thermoplastic elastomer which is a polymer having a structural unit derived from a conjugated diene compound and a structural unit derived from an aromatic vinyl compound; conjugated diene-based elastomers such as polybutadiene rubber and polyisoprene rubber are preferable, and conjugated diene-aromatic vinyl-based thermoplastic elastomers are preferable, and among the conjugated diene-aromatic vinyl-based thermoplastic elastomers, unhydrogenated conjugated diene-aromatic vinyl-based thermoplastic elastomers are particularly preferable.

The conjugated diene-aromatic vinyl thermoplastic elastomer used as the additive having a polydiene structure in the present invention has an unsaturated bond capable of undergoing a polymerization reaction in its structure, and by having such an unsaturated bond capable of undergoing a polymerization reaction, the unsaturated bond capable of undergoing a polymerization reaction reacts with the binder resin, whereby the conjugated diene-aromatic vinyl thermoplastic elastomer interacts with the release agent in a state of being fixed to the binder resin. In addition, the release agent can be finely dispersed in the binder resin constituting the colored resin particles, and as a result, blocking of the obtained toner can be effectively suppressed, and the effect of improving low-temperature fixability by adding the release agent can be sufficiently exhibited, and as a result, the storage stability and low-temperature fixability of the obtained toner can be further improved. In the present invention, the "unsaturated bond capable of undergoing polymerization" means an unsaturated bond having polymerization activity, and an olefinic carbon-carbon double bond having polymerization activity can be preferably cited.

Examples of the conjugated diene-aromatic vinyl thermoplastic elastomer used in the present invention include random, block, graft copolymers of a conjugated diene monomer, an aromatic vinyl monomer, and optionally another monomer copolymerizable therewith, and hydrogenated products of such copolymers.

The conjugated diene-aromatic vinyl thermoplastic elastomer is not particularly limited, and a block copolymer containing at least 1 aromatic vinyl polymer block and at least 1 conjugated diene polymer block can be preferably used from the viewpoint of further improving the storage stability and low-temperature fixability of the toner.

Hereinafter, a block copolymer (hereinafter, may be simply referred to as "block copolymer") including at least 1 aromatic vinyl polymer block and at least 1 conjugated diene polymer block, which is a typical example of a conjugated diene-aromatic vinyl thermoplastic elastomer, will be described. The block copolymer used in the present invention comprises at least 1 aromatic vinyl polymer block obtained by polymerizing an aromatic vinyl monomer and a conjugated diene polymer block obtained by polymerizing a conjugated diene monomer, respectively.

The aromatic vinyl monomer is not particularly limited as long as it is an aromatic vinyl compound, and examples thereof include styrene, α -methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2, 4-diisopropylstyrene, 2, 4-dimethylstyrene, 4-tert-butylstyrene, 5-tert-butyl-2-methylstyrene, 2-chlorostyrene, 3-chlorostyrene, 4-bromostyrene, 2-methyl-4, 6-dichlorostyrene, 2, 4-dibromostyrene, and vinylnaphthalene. Among them, styrene is preferably used. These aromatic vinyl monomers can be used alone or in combination of two or more in each aromatic vinyl polymer block. In the case where the block copolymer has a plurality of aromatic vinyl polymer blocks, the respective aromatic vinyl polymer blocks may be composed of the same aromatic vinyl monomer unit or may be composed of different aromatic vinyl monomer units.

The aromatic vinyl polymer block may contain a monomer unit other than the aromatic vinyl monomer unit as long as the aromatic vinyl monomer unit is a main repeating unit. Examples of other monomers that can be used in the aromatic vinyl polymer block include: conjugated diene monomers such as 1, 3-butadiene and isoprene (2-methyl-1, 3-butadiene); an α, β -unsaturated nitrile monomer; unsaturated carboxylic acid or anhydride monomers; an unsaturated carboxylic acid ester monomer; non-conjugated diene monomers, and the like. The content of the monomer unit other than the aromatic vinyl monomer unit in the aromatic vinyl polymer block is preferably 20% by mass or less, more preferably 10% by mass or less, and particularly preferably substantially 0% by mass.

The conjugated diene monomer is not particularly limited as long as it is a conjugated diene compound, and examples thereof include 1, 3-butadiene, isoprene, 2, 3-dimethyl-1, 3-butadiene, 2-chloro-1, 3-butadiene, 1, 3-pentadiene, 1, 3-hexadiene, and the like. Among them, 1, 3-butadiene and/or isoprene are preferably used, and isoprene is particularly preferably used, from the viewpoint of high effect of improving storage stability and low-temperature fixability. These conjugated diene monomers can be used alone or in combination of two or more in each conjugated diene polymer block. In the case where the block copolymer has a plurality of conjugated diene polymer blocks, the respective conjugated diene polymer blocks may be composed of the same conjugated diene monomer unit or may be composed of different conjugated diene monomer units. Further, a part of the unsaturated bonds of each conjugated diene polymer block may be subjected to hydrogenation reaction.

The conjugated diene polymer block may contain a monomer unit other than the conjugated diene monomer unit as long as the conjugated diene monomer unit is a main repeating unit. Examples of other monomers that can be used in the conjugated diene polymer block include: aromatic vinyl monomers such as styrene and alpha-methylstyrene; an α, β -unsaturated nitrile monomer; unsaturated carboxylic acid monomers; unsaturated carboxylic acid anhydride monomer; an unsaturated carboxylic acid ester monomer; non-conjugated diene monomers, and the like. The content of the monomer unit other than the conjugated diene monomer unit in the conjugated diene polymer block is preferably 20% by mass or less, more preferably 10% by mass or less, and particularly preferably substantially 0% by mass.

The vinyl bond content (the proportion of the 1, 2-vinyl bond unit and the 3, 4-vinyl bond unit in the total conjugated diene monomer units in the conjugated diene polymer block) of the conjugated diene polymer block is not particularly limited, but is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and particularly preferably 3 to 10 mol%.

The number of the respective polymer blocks and the bonding mode thereof are not particularly limited as long as the block copolymer contains at least 1 aromatic vinyl polymer block and conjugated diene polymer block. Specific examples of the block copolymer used in the present invention include the following. In the following specific examples, Ar represents an aromatic vinyl polymer block, D represents a conjugated diene polymer block, X represents a residue of a coupling agent, and n represents an integer of 2 or more.

(a) Aromatic vinyl-conjugated diene block copolymer represented by Ar-D

(b) Aromatic vinyl-conjugated diene-aromatic vinyl block copolymer represented by Ar-D-Ar and/or (Ar-D) n-X

(c) A conjugated diene-aromatic vinyl-conjugated diene block copolymer represented by D-Ar-D and/or (D-Ar) n-X

(d) An aromatic vinyl-conjugated diene-aromatic vinyl-conjugated diene block copolymer represented by Ar-D-Ar-D,

(e) a block copolymer composition comprising two or more of the above-mentioned (a) to (d) in an arbitrary combination

In the present invention, as the block copolymer, a block copolymer containing at least the aromatic vinyl-conjugated diene block copolymer represented by the above-mentioned (a) is preferably used, and a block copolymer containing at least the aromatic vinyl-conjugated diene block copolymer represented by the above-mentioned (a) and the aromatic vinyl-conjugated diene block copolymer represented by the above-mentioned (b) and Ar-D-Ar and/or (Ar-D) n-X is more preferably used. The content of the aromatic vinyl-conjugated diene block copolymer represented by Ar-D (i.e., a diblock copolymer comprising an aromatic vinyl polymer block and a block of a polymer copolymerizable with the aromatic vinyl polymer) in the conjugated diene-aromatic vinyl thermoplastic elastomer used in the present invention is preferably 40% by mass (wt%) or more, preferably 50% by mass or more, and more preferably 55% by mass or more. The upper limit is not particularly limited, but is preferably 98% by mass or less, and more preferably 95% by mass or less. By setting the content of the aromatic vinyl-conjugated diene block copolymer represented by Ar-D (i.e., a diblock copolymer composed of an aromatic vinyl polymer block and a block of a polymer copolymerizable with the aromatic vinyl polymer) in the conjugated diene-aromatic vinyl thermoplastic elastomer used in the present invention to 40 mass% or more, the obtained toner can be made highly chargeable, bleeding of the release agent can be suppressed, and ejection and adhesion to a blade under high-temperature and high-humidity conditions can be effectively suppressed.

In the aromatic vinyl-conjugated diene block copolymer represented by Ar-D, the weight average molecular weight (Mw (Ar)) of the aromatic vinyl polymer block Ar is not particularly limited, preferably 10000 to 50000, more preferably 15000 to 30000, and the weight average molecular weight (Mw (D)) of the conjugated diene polymer block D is not particularly limited, preferably 50000 to 200000, more preferably 60000 to 150000.

Further, the weight average molecular weight (Mw (Ar)) of the aromatic vinyl polymer block Ar in the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer represented by Ar-D-Ar and/or (Ar-D) n-X is not particularly limited, preferably 20000 to 70000, more preferably 25000 to 50000, and the weight average molecular weight (Mw (D)) of the conjugated diene polymer block D in the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer represented by Ar-D-Ar and/or (Ar-D) n-X is not particularly limited, preferably 100000 to 300000, more preferably 120000 to 250000.

The weight average molecular weights are polystyrene values measured by Gel Permeation Chromatography (GPC) using tetrahydrofuran.

The content ratio of the aromatic vinyl monomer unit in the block copolymer used in the present invention to the total monomer units is preferably 10 to 30% by mass, more preferably 12 to 25% by mass, and still more preferably 15 to 25% by mass. When the content ratio of the aromatic vinyl monomer unit is in the above range, the affinity of the block copolymer for the release agent and the affinity of the block copolymer for the binder resin can be highly balanced, and the obtained toner can be further excellent in storage stability and low-temperature fixing property.

In the case where the entire polymer component constituting the block copolymer is composed of only aromatic vinyl monomer units and conjugated diene monomer units, the content of the aromatic vinyl monomer units in the block copolymer can be measured by decomposing the block copolymer with ozone according to the method described in Rubber chem.

The weight average molecular weight (Mw) of the aromatic vinyl monomer unit in the block copolymer is not particularly limited, but is preferably 10000 to 50000, more preferably 20000 to 40000, in terms of polystyrene as measured by Gel Permeation Chromatography (GPC) using tetrahydrofuran. The weight average molecular weight (Mw) of the conjugated diene monomer unit in the block copolymer is not particularly limited, but is preferably 50000 to 200000, and more preferably 60000 to 180000.

The Melt Index (MI) of the block copolymer is not particularly limited, and is selected, for example, from 1 to 1000G/10 min, preferably from 5 to 30G/10 min, as a value measured in accordance with ASTM D-1238(G condition, 200 ℃,5 kg).

The block copolymer used in the present invention can be produced by a conventional method. Examples of the method for producing such a block copolymer include a method in which an aromatic vinyl monomer and a conjugated diene monomer are polymerized in sequence to form polymer blocks by an anionic living polymerization method, and a coupling agent is reacted to perform coupling as necessary.

In addition, in the case where a block copolymer comprising at least the above-mentioned (a) aromatic vinyl-conjugated diene block copolymer represented by Ar-D and (b) aromatic vinyl-conjugated diene-aromatic vinyl block copolymer represented by Ar-D-Ar and/or (Ar-D) n-X is used as the block copolymer used in the present invention, the following method can be employed.

Namely, the following methods can be mentioned: first, an aromatic vinyl monomer is polymerized by an anionic living polymerization method, and then a conjugated diene monomer is added to carry out polymerization, thereby obtaining a diblock copolymer having a living terminal. Next, a coupling agent is added to the active terminal of the diblock copolymer having an active terminal in an amount of less than 1 molar equivalent to cause a coupling reaction of a part of the diblock copolymer having an active terminal to obtain an aromatic vinyl-conjugated diene-aromatic vinyl block copolymer represented by (Ar-D) n-X, and then a polymerization terminator is added to inactivate the remaining diblock copolymer having an active terminal to obtain a diblock copolymer represented by Ar-D. In this case, by using a 2-functional coupling agent such as dichlorosilane, monomethyldichlorosilane, dichlorodimethylsilane, diphenyldimethoxysilane, diphenyldiethoxysilane, dichloroethane, dibromoethane, dichloromethane, and dibromomethane as a coupling agent, an aromatic vinyl-conjugated diene-aromatic vinyl block copolymer (D contains a residue of the coupling agent) represented by Ar-D-Ar can be obtained.

In the present invention, the content ratio of (a) the aromatic vinyl-conjugated diene block copolymer represented by Ar-D and (b) the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer represented by Ar-D-Ar and/or (Ar-D) n-X is not particularly limited, and the content ratio of (a) the aromatic vinyl-conjugated diene block copolymer represented by Ar-D is preferably 10 to 90% by mass, more preferably 20 to 80% by mass. The content ratio of the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer (b) represented by Ar-D-Ar and/or (Ar-D) n-X is preferably 10 to 90% by mass, more preferably 20 to 80% by mass.

In addition, as the conjugated diene-aromatic vinyl-based thermoplastic elastomer, a random copolymer of an aromatic vinyl monomer and a conjugated diene monomer may be used instead of the above-described block copolymer. The random copolymer of an aromatic vinyl monomer and a conjugated diene monomer can be produced by, for example, living anion polymerization using an organic alkali metal compound as a polymerization initiator. Examples of the organic alkali metal compound include organic lithium compounds, organic sodium compounds, and organic potassium compounds, and specifically include: organic monolithium compounds such as n-butyllithium, sec-butyllithium, tert-butyllithium, hexyllithium, phenyllithium, and distyryllithium; organic polyvalent lithium compounds such as dilithiomethane, 1, 4-dilithiobutane, 1, 4-dilithio-2-ethylcyclohexane, 1,3, 5-trilithiobenzene, and 1,3, 5-tris (lithiomethyl) benzene; organic sodium compounds such as sodium naphthalene; and organic potassium compounds such as potassium naphthalene. Among these organometallic compounds, n-butyllithium is preferably used.

The content ratio of the aromatic vinyl monomer unit in the random copolymer of the aromatic vinyl monomer and the conjugated diene monomer used in the present invention to the total monomer units is preferably 50% by mass or less, more preferably 45% by mass or less, and still more preferably 40% by mass or less. When the content ratio of the aromatic vinyl monomer unit is in the above range, the affinity of the random copolymer for the release agent and the affinity of the random copolymer for the binder resin can be highly balanced, and the resulting toner can be further excellent in storage stability and low-temperature fixing property.

In the present invention, as the additive having a polydiene structure, a conjugated diene elastomer such as polybutadiene rubber or polyisoprene rubber can be preferably used. Conjugated diene elastomers such as polybutadiene rubber and polyisoprene rubber can be produced by living anionic polymerization using an organic alkali metal compound as a polymerization initiator. As the organic alkali metal compound, for example, the above-mentioned organic alkali metal compound can be used.

The weight average molecular weight (Mw) of the additive having a polydiene structure used in the present invention is not particularly limited, but is preferably 60000 to 350000, more preferably 80000 to 250000, in terms of polystyrene as measured by Gel Permeation Chromatography (GPC) using tetrahydrofuran. When the weight average molecular weight (Mw) is in the above range, the storage stability and low-temperature fixability of the obtained toner can be further improved.

The content of the additive having a polydiene structure is preferably 1 to 10 parts by mass, more preferably 1.5 to 8 parts by mass, and still more preferably 2 to 5 parts by mass, per 100 parts by mass of the binder resin (100 parts by mass of the polymerizable monomer for obtaining the binder resin). When the content of the additive having a polydiene structure is in the above range, the effect of the addition, that is, the effect of improving the storage stability and low-temperature fixability of the obtained toner can be further improved.

In the present invention, an acrylic resin can be used as another additive to further suppress bleeding of the release agent.

The acrylic resin is a copolymer (acrylate copolymer) containing as main components at least any one of acrylic acid ester and methacrylic acid ester and at least any one of acrylic acid and methacrylic acid. As the acid monomer, acrylic acid is preferable.

Examples of the acrylic resin include copolymers of acrylic acid esters and acrylic acid, copolymers of acrylic acid esters and methacrylic acid, copolymers of methacrylic acid esters and acrylic acid, copolymers of methacrylic acid esters and methacrylic acid, copolymers of acrylic acid esters and methacrylic acid, and copolymers of acrylic acid esters and methacrylic acid esters and acrylic acid and methacrylic acid. Among them, copolymers of acrylic acid esters with methacrylic acid esters with acrylic acid are preferably used.

The acid value of the acrylic resin is usually 0.5 to 7mgKOH/g, preferably 1 to 6mgKOH/g, and more preferably 1.5 to 4 mgKOH/g. When the acid value of the acrylic resin is in the above range, desired colored resin particles can be produced satisfactorily, and the heat-resistant storage property, the low-temperature fixing property, and the printing durability in a temperature and humidity environment ranging from a low-temperature low-humidity environment to a high-temperature high-humidity environment can be satisfactory.

The acid value of the acrylic resin is a value measured in accordance with JIS K0070, which is a standard oil and fat analysis method established by the japan industrial standards institute (JISs).

The weight average molecular weight (Mw) of the acrylic resin is usually 6000 to 50000, preferably 8000 to 25000, and more preferably 10000 to 20000.

When the weight average molecular weight (Mw) of the acrylic resin is in the above range, the heat-resistant storage property, the durability and the low-temperature fixability can be improved.

The glass transition temperature Tg of the acrylic resin is usually 60 to 85 ℃, preferably 65 to 80 ℃, and more preferably 70 to 77 ℃. When the glass transition temperature is in the above range, heat-resistant storage stability and low-temperature fixability can be made good.

The glass transition temperature Tg of the acrylic resin can be determined, for example, in accordance with ASTM D3418-82.

The ratio of the acrylate monomer unit, the methacrylate monomer unit, the acrylic acid monomer unit, and the methacrylic acid monomer unit in the acrylic resin is not particularly limited as long as the acid value, the weight average molecular weight Mw, and the glass transition temperature described above are satisfied.

The ratio of the above 4 monomer units can be adjusted by the mass ratio of the amounts of the added acrylate, methacrylate, acrylic acid and methacrylic acid at the time of copolymer synthesis. The mass ratio of the addition amount may be, for example, (acrylic acid ester and/or methacrylic acid ester): (acrylic acid and/or methacrylic acid): (99 to 99.95): (0.05 to 1), preferably (acrylic acid ester and/or methacrylic acid ester): (acrylic acid and/or methacrylic acid): (99.4 to 99.9): 0.1 to 0.6), more preferably (acrylic acid ester and/or methacrylic acid ester): (acrylic acid and/or methacrylic acid): (99.5-99.7): (0.3-0.5). In addition, the acrylic acid ester and/or methacrylic acid ester in these polymerizable monomers may be replaced with other monomers such as styrene derivatives, nitrile compounds, and amide compounds exemplified as the monovinyl monomers constituting the above binder resin, within a range not to impair the effects of the present invention. The proportion thereof is 10 mass% or less, preferably 2 mass% or less, preferably not substituted, of the total amount of the added acrylate and/or methacrylate.

Examples of the acrylic ester usable in the acrylic resin include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, n-pentyl acrylate, sec-pentyl acrylate, isopentyl acrylate, neopentyl acrylate, n-hexyl acrylate, isohexyl acrylate, neohexyl acrylate, sec-hexyl acrylate, and tert-hexyl acrylate, among which ethyl acrylate, n-propyl acrylate, isopropyl acrylate, and n-butyl acrylate are preferable, and n-butyl acrylate is more preferable.

Examples of the methacrylic acid ester usable in the acrylic resin include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, n-pentyl methacrylate, sec-pentyl methacrylate, isopentyl methacrylate, neopentyl methacrylate, n-hexyl methacrylate, isohexyl methacrylate, neohexyl methacrylate, sec-hexyl methacrylate, and tert-hexyl methacrylate, among which methyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, and n-butyl methacrylate are preferable, and methyl methacrylate is more preferable.

The amount of the acrylic resin added is preferably 0.3 to 4 parts by mass, more preferably 0.5 to 3.0 parts by mass, and still more preferably 0.7 to 2.0 parts by mass, based on 100 parts by mass of the binder resin (100 parts by mass of the polymerizable monomer for obtaining the binder resin). When the amount of the acrylic resin added is in the above range, the environmental stability can be improved and the effect of the addition can be sufficiently exhibited.

The acrylic resin may be a commercially available acrylic resin, or may be produced by a known method such as solution polymerization, aqueous solution polymerization, ion polymerization, high-temperature high-pressure polymerization, or suspension polymerization.

Further, as other additives, a molecular weight modifier may be used. The molecular weight regulator is not particularly limited as long as it is a molecular weight regulator that is generally used as a molecular weight regulator for toner, and examples thereof include: mercaptans such as t-dodecylmercaptan, n-octylmercaptan, and 2,2,4,6, 6-pentamethylheptane-4-mercaptan; thiuram disulfides such as tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, N '-dimethyl-N, N' -diphenylthiuram disulfide, and N, N '-dioctadecyl-N, N' -diisopropylthiuram disulfide. These molecular weight regulators may be used either individually or in combination of two or more. The amount of the molecular weight modifier used is preferably 0.01 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the binder resin (100 parts by mass of the polymerizable monomer for obtaining the binder resin).

(A-2) suspension step (droplet formation step) for obtaining a suspension

Next, the polymerizable monomer composition obtained in the step of preparing the polymerizable monomer composition (a-1) and containing the polymerizable monomer, the colorant, the charge control agent, the release agent, and the additive having a polydiene structure is dispersed in an aqueous dispersion medium, and after a polymerization initiator is added, droplets of the polymerizable monomer composition are formed. Here, the term "suspension" means that droplets of the polymerizable monomer composition are formed in an aqueous dispersion medium. The dispersion treatment for the droplet formation can be performed using a device capable of strong stirring such as an in-line type emulsion disperser (manufactured by ltd., trade name: mill), a high-speed emulsion/disperser (manufactured by PRIMIX Corporation, trade name: t.k. homomi xer MARK II), and the like.

Examples of the polymerization initiator include: persulfates such as potassium persulfate and ammonium persulfate; azo compounds such as 4,4' -azobis (4-cyanovaleric acid), 2' -azobis (2-methyl-N- (2-hydroxyethyl) propionamide), 2' -azobis (2-amidinopropane) dihydrochloride, 2' -azobis (2, 4-dimethylvaleronitrile), and 2,2' -azobisisobutyronitrile; organic peroxides such as di-t-butyl peroxide, benzoyl peroxide, t-butyl peroxy-2-ethylhexanoate, t-hexyl peroxy-2-ethylbutyrate, diisopropyl peroxydicarbonate, di-t-butyl peroxyisobutyrate, and t-butyl peroxyisobutyrate. They may be used alone or in combination of two or more. Among them, organic peroxides are preferably used from the viewpoint of reducing residual polymerizable monomers and also having excellent printing durability. Among the organic peroxides, peroxyesters are preferred, and non-aromatic peroxyesters, i.e., peroxyesters having no aromatic ring, are more preferred, from the viewpoint of good initiator efficiency and reduction in residual polymerizable monomers.

As described above, the polymerization initiator may be added after the polymerizable monomer composition is dispersed in the aqueous medium and before the droplets are formed, or may be added to the polymerizable monomer composition before the polymerizable monomer composition is dispersed in the aqueous medium (a medium containing water as a main component).

The amount of the polymerization initiator used for polymerization of the polymerizable monomer composition is preferably 0.1 to 20 parts by mass, more preferably 0.3 to 15 parts by mass, and particularly preferably 1 to 10 parts by mass, per 100 parts by mass of the binder resin (100 parts by mass of the polymerizable monomer for obtaining the binder resin).

In the present invention, the aqueous medium preferably contains a dispersion stabilizer. Examples of the dispersion stabilizer include: sulfates such as barium sulfate and calcium sulfate; carbonates such as barium carbonate, calcium carbonate, and magnesium carbonate; phosphates such as calcium phosphate; metal oxides such as aluminum oxide and titanium oxide; inorganic compounds such as metal hydroxides including aluminum hydroxide, magnesium hydroxide, and iron hydroxide; water-soluble polymers such as polyvinyl alcohol, methyl cellulose, and gelatin; an anionic surfactant; a nonionic surfactant; organic compounds such as amphoteric surfactants. The dispersion stabilizer may be used in 1 kind or in combination of two or more kinds. The amount of the dispersion stabilizer to be added is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 10 parts by mass, per 100 parts by mass of the binder resin (100 parts by mass of the polymerizable monomer for obtaining the binder resin).

Among the above dispersion stabilizers, inorganic compounds, particularly colloids of metal hydroxides which are hardly soluble in water, are preferred. By using an inorganic compound, particularly a colloid of a metal hydroxide which is hardly soluble in water, the particle size distribution of the colored resin particles can be narrowed, and the remaining amount of the dispersion stabilizer after washing can be reduced, so that the obtained toner can reproduce an image more clearly without deteriorating environmental stability.

(A-3) polymerization step

By heating the desired suspension (aqueous dispersion medium containing droplets of the polymerizable monomer composition) obtained in the step (a-2) of obtaining a suspension (droplet forming step) to initiate polymerization, an aqueous dispersion of colored resin particles containing a binder resin, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure can be obtained.

The polymerization temperature in the present invention is preferably 50 ℃ or higher, and more preferably 60 to 95 ℃. In addition, the polymerization time in the present invention is preferably 1 to 20 hours, more preferably 2 to 15 hours.

In addition, from the viewpoint of performing polymerization in a state in which droplets of the polymerizable monomer composition are stably dispersed, the polymerization reaction may be performed while performing dispersion treatment by stirring, following the step (a-2) of obtaining a suspension (droplet forming step) in the polymerization step.

In the present invention, an external additive may be directly added to the colored resin particles thus obtained to be used as a toner, and the following colored resin particles may be prepared: the colored resin particles obtained in the polymerization step are used as a core layer, and a shell layer different from the core layer is formed on the outer side of the core layer, thereby obtaining a so-called core-shell type (or also referred to as "capsule type") colored resin particle. The core-shell type colored resin particles can further improve the storage stability and low-temperature fixability of the obtained toner by coating the core layer made of a low softening point material with a material having a higher softening point than the core layer.

The method for producing the core-shell type colored resin particles is not particularly limited, and the core-shell type colored resin particles can be produced by a conventionally known method, and in-situ polymerization (in situ polymerization) and phase separation are preferable from the viewpoint of production efficiency.

A method for producing core-shell colored resin particles by in-situ polymerization will be described below.

In the in-situ polymerization method, a polymerizable monomer for forming a shell layer (polymerizable monomer for a shell) and a polymerization initiator for a shell are added to an aqueous dispersion medium in which the colored resin particles are dispersed, and polymerization is performed, thereby obtaining core-shell-type colored resin particles.

As the shell polymerizable monomer, the same polymerizable monomers as those described above can be used. Among them, monomers which can give a polymer having a Tg of more than 80 ℃ such as styrene and methyl methacrylate are preferably used singly or in combination.

Examples of the polymerization initiator for a shell used for polymerization of the polymerizable monomer for a shell include: metal persulfates such as potassium persulfate and ammonium persulfate; and polymerization initiators such as water-soluble azo compounds, for example, 2 '-azobis (2-methyl-N- (2-hydroxyethyl) propionamide) and 2,2' -azobis- (2-methyl-N- (1, 1-bis (hydroxymethyl) -2-hydroxyethyl) propionamide). The amount of the polymerization initiator for the shell is preferably 0.1 to 30 parts by mass, and more preferably 1 to 20 parts by mass, based on 100 parts by mass of the polymerizable monomer for the shell.

The polymerization temperature of the shell layer is preferably 50 ℃ or higher, and more preferably 60 to 95 ℃. In addition, the polymerization time of the shell layer is preferably 1 to 20 hours, and more preferably 2 to 15 hours.

(A-4) washing, filtration, dehydration and drying step

The aqueous dispersion of colored resin particles obtained in the polymerization step (A-3) is preferably subjected to a series of washing, filtration, dehydration and drying, as required, several times in accordance with a conventional method after completion of the polymerization.

First, in order to remove the dispersion stabilizer remaining in the aqueous dispersion of the colored resin particles, it is preferable to wash the aqueous dispersion of the colored resin particles by adding an acid or an alkali thereto. When the dispersion stabilizer to be used is an acid-soluble inorganic compound, it is preferable to wash the colored resin particles by adding an acid to the aqueous dispersion thereof, and when the dispersion stabilizer to be used is an alkali-soluble inorganic compound, it is preferable to wash the colored resin particles by adding an alkali to the aqueous dispersion thereof.

In addition, in the case where an acid-soluble inorganic compound is used as the dispersion stabilizer, it is preferable to adjust the pH to preferably 6.5 or less, more preferably 6 or less by adding an acid to the aqueous dispersion of the colored resin particles. As the acid to be added, inorganic acids such as sulfuric acid, hydrochloric acid, and nitric acid, and organic acids such as formic acid and acetic acid can be used, and sulfuric acid is particularly preferable because the removal efficiency of the dispersion stabilizer is high and the load on the production equipment is small.

The method of dehydration and filtration is not particularly limited, and various known methods can be used. Examples thereof include centrifugal filtration, vacuum filtration, and pressure filtration. The method of drying is also not particularly limited, and various methods can be used.

(B) Crushing method

In the case of producing the colored resin particles by the pulverization method, the production can be carried out by the following steps.

First, a binder resin, a colorant, a charge control agent, a release agent, an additive having a polydiene structure, and further other additives added as needed are mixed using a Mixer such as a ball mill, a V-type Mixer, an FM Mixer (trade name), a high-speed mixing dissolver, an internal Mixer, and Forberg. Next, the mixture obtained above is kneaded while being heated using a pressure kneader, a twin-screw extruder, a roll, or the like. The obtained kneaded material is coarsely pulverized using a pulverizer such as a hammer mill, a chopper, a roll mill or the like. Further, the colored resin particles can be obtained by a pulverization method by finely pulverizing the resin particles with a pulverizer such as a jet mill or a high-speed rotary mill and then classifying the pulverized resin particles into a desired particle size with a classifier such as an air classifier or an air classifier.

The binder resin, the colorant, the charge control agent, the release agent, and the additive having a polydiene structure used in the pulverization method, and further, other additives added as needed can be used as those exemplified in the suspension polymerization method (a) described above. The colored resin particles obtained by the pulverization method can be made into core-shell type colored resin particles by an in-situ polymerization method or the like, similarly to the colored resin particles obtained by the suspension polymerization method (a) described above.

As the binder resin, in addition to the above binder resins, resins which have been widely used in toners can be used. Specific examples of the binder resin used in the pulverization method include polystyrene, styrene-butyl acrylate copolymer, polyester resin, epoxy resin, and the like.

(colored resin particles)

The colored resin particles can be obtained by the suspension polymerization method (a) or the pulverization method (B).

Hereinafter, the colored resin particles constituting the toner will be described. The colored resin particles described below include both core-shell type colored resin particles and non-core-shell type colored resin particles.

In the colored resin particle used in the first aspect of the present invention, a specific number of the above-mentioned crystal domains having a specific shape are contained as the crystal domains of the release agent contained in the colored resin particle. That is, when the cross section of the colored resin particle is observed by a Transmission Electron Microscope (TEM), the number of domains of the release agent having an aspect ratio in the range of 2 to 10 is in the range of 2 to 30 in a field of view of 2 μm × 2 μm square of the cross section of the colored resin particle. In the aspect 1 of the present invention, the release agent contained in the colored resin particles is finely dispersed in a state having a domain structure with an aspect ratio of 2 to 10, and the number of the domains is in a range of 2 to 30 in a field of view of 2 μm × 2 μm square, whereby blocking of the obtained toner can be effectively suppressed, and the effect of improving low-temperature fixability by adding the release agent can be sufficiently exhibited. As a result, the obtained toner can be excellent in storage stability and low-temperature fixability.

The number of the release agent domains having an aspect ratio in the range of 2 to 10 in a field of view of 2 [ mu ] m × 2 [ mu ] m square is 2 to 30, preferably 3 to 27, and more preferably 5 to 25. In view of further improving the effect of the present invention, in the aspect 1 of the present invention, it is preferable that the number of the domains of the release agent having an aspect ratio in the range of 3 to 8 is also in the above range in the field of view of 2 μm × 2 μm square.

The number of the release agent crystal domains having an aspect ratio in the range of 2 to 10 and the number of the release agent crystal domains having an aspect ratio in the range of 3 to 8 in a field of view of 2. mu. m.times.2 μm square can be measured, for example, by the following method. That is, first, colored resin particles are dispersed in an epoxy resin, then cured, cooled to a temperature of-80 ℃, and then cut by a slicer to prepare a thin sheet. Then, the sheet was dyed with a ruthenium tetroxide aqueous vapor, observed with a Transmission Electron Microscope (TEM), and the number of domains of the release agent and the aspect ratio of the domains of the release agent, which are present in a field of view of 2 μm × 2 μm square of the cross section of the colored resin particles, were calculated by image analysis. Then, the number of the crystal domains of the mold release agent having an aspect ratio in the range of 2 to 10 and the number of the crystal domains of the mold release agent having an aspect ratio in the range of 3 to 8 can be obtained. In these measurements, the number of the domains of the release agent having an aspect ratio in the range of 2 to 10 and the number of the domains of the release agent having an aspect ratio in the range of 3 to 8 of the colored resin particles observed in the visual field range can be calculated, and the number of the domains of the release agent having an aspect ratio in the range of 2 μm × 2 μm is converted into the number of the domains of the visual field range in the range of 2 μm × 2 μm based on the obtained calculation result, and the number is used as the measurement value.

The method of setting the number of crystal domains of the release agent having an aspect ratio in the range of 2 to 10 to the above range is not particularly limited, and a method of adding an additive having a polydiene structure to the colored resin particles is exemplified. Specifically, by containing the additive having a polydiene structure, the release agent can be appropriately dispersed in the colored resin particles by utilizing the compatibility of the additive having a polydiene structure with the release agent, and thus the number of crystal domains of the release agent having an aspect ratio in the range of 2 to 10 can be made to fall within the above range. In addition, in the aspect 1 of the present invention, the method of controlling the number of crystal domains of the release agent having an aspect ratio in the range of 2 to 10 to be in the above range is not particularly limited, and may be a method of adjusting the type of the additive having a polydiene structure to be used, the type of the release agent to be used, the amount of the additive having a polydiene structure to be used, and the amount of the release agent to be used, and the like, and they may be combined.

The average aspect ratio of the domains of the release agent contained in the colored resin particles is not particularly limited, but is preferably 2 to 10, more preferably 3 to 9, and still more preferably 3.5 to 8.5. The average major axis (average of major axes) of the domains of the release agent is preferably 0.20 to 1.0 μm, more preferably 0.25 to 0.90 μm, and the average minor axis (average of minor axes) of the domains of the release agent is preferably 0.03 to 0.15 μm, more preferably 0.04 to 0.10 μm. When the average aspect ratio, the average major axis, and the average minor axis of the domains of the release agent are within the above ranges, the effect of improving the storage stability and the low-temperature fixability can be further improved. The average aspect ratio, average major axis, and average minor axis of the domains of the release agent can be determined by the following methods: when the number of crystal domains of the release agent having an aspect ratio in the range of 2 to 10 and the number of crystal domains of the release agent having an aspect ratio in the range of 3 to 8 are measured, the aspect ratio, the major axis and the minor axis are measured for each of the crystal domains of the release agent to be measured, and the average value of the crystal domains of all the release agents to be measured is calculated.

From the viewpoint of image reproducibility, the volume average particle diameter Dv of the colored resin particles is preferably 3 to 15 μm, more preferably 4 to 12 μm, and still more preferably 5 to 8 μm. When the volume average particle diameter Dv of the colored resin particles is smaller than the above range, the fluidity of the toner may be reduced, and image quality may be easily deteriorated due to fog or the like. On the other hand, when the volume average particle diameter Dv of the colored resin particles exceeds the above range, the resolution of the obtained image may be lowered.

In addition, from the viewpoint of image reproducibility, the particle size distribution (Dv/Dn) which is the ratio of the volume average particle size (Dv) to the number average particle size (Dn) of the colored resin particles is preferably 1.00 to 1.30, and more preferably 1.00 to 1.20. When the particle size distribution (Dv/Dn) of the colored resin particles exceeds the above range, the fluidity of the toner may be reduced, and image quality may be easily deteriorated due to fog or the like. The volume average particle diameter Dv and the number average particle diameter Dn of the colored resin particles can be measured using, for example, a particle size analyzer (BECKMAN COULTER co., ltd., product name: Multisizer).

In addition, from the viewpoint of image reproducibility, the average circularity of the colored resin particles is preferably 0.960 to 1.000, more preferably 0.970 to 1.000, and still more preferably 0.980 to 1.000.

In addition, the gel content (tetrahydrofuran insoluble matter content) of the colored resin particles is preferably 1 to 50 wt%, more preferably 5 to 47 wt%, further preferably 10 to 45 wt%, and particularly preferably 15 to 40 wt%, from the viewpoint of improving the heat offset property and the low temperature fixing property.

The weight average molecular weight (Mw) of the colored resin particles is preferably 20000 to 200000, more preferably 30000 to 180000, still more preferably 35000 to 150000, and particularly preferably 40000 to 90000.

The colored resin particles described above may be used as a toner as they are or as a toner by mixing carrier particles (ferrite, iron powder, etc.) with the colored resin particles, and in order to adjust the charging property, fluidity, storage property, etc. of the toner, a high-speed Mixer (for example, FM Mixer (trade name, Nippon Coke & Engineering co., ltd.) or the like) may be used, and external additives may be added/mixed to the colored resin particles to prepare a single-component toner, and further, the colored resin particles and the external additives may be mixed and the carrier particles may be further mixed to prepare a two-component toner.

The stirrer used for the external addition treatment is not particularly limited as long as it is a stirrer capable of adhering an external additive to the surface of the colored resin particles, and the external addition treatment can be performed using a stirrer capable of performing mixing stirring, such as FM Mixer (trade name, Nippon Coke & Engineering co., ltd., manufactured by ltd.), Super Mixer (trade name, manufactured by kawa Corporation), Q Mixer (trade name, Nippon Coke & Engineering co., ltd., manufactured by ltd.), Mechanofusion System (trade name, manufactured by Hosokawa Micron Corporation), and mecanomill (trade name, OKADA seiko.co., ltd.).

Examples of the external additive include: inorganic fine particles containing silica, titanium oxide, alumina, zinc oxide, tin oxide, calcium carbonate, calcium phosphate, cerium oxide, and the like; organic fine particles including polymethyl methacrylate resin, silicone resin, melamine resin, and the like. Among them, inorganic fine particles are preferable, silica and titanium oxide are more preferable, and silica is particularly preferable. Further, it is preferable to use two or more kinds of fine particles as the external additive in combination. These external additives may be used alone, but two or more kinds thereof are preferably used in combination.

The external additive is desirably used in a proportion of preferably 0.3 to 6 parts by mass, more preferably 1.2 to 3 parts by mass, per 100 parts by mass of the colored resin particles.

The toner according to claim 1 of the present invention is a toner that is excellent in storage stability and low-temperature fixability, and therefore can sufficiently meet recent requirements for reduction in energy consumption and increase in printing speed, because colored resin particles that contain a binder resin, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure and having a solubility in styrene at 40 ℃ of 3 to 40g/100g, and the number of domains of the release agent having an aspect ratio in a range of 2 to 10 in a field of view of 2 μm × 2 μm in a cross section of the colored resin particles observed by a Transmission Electron Microscope (TEM) is 2 to 30.

< toner for developing Electrostatic image according to claim 2 >

Further, the toner for developing electrostatic images according to claim 2 of the present invention contains colored resin particles containing a binder resin, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure.

The solubility of the additive with a polydiene structure in styrene at a temperature of 40 ℃ is 3-40 g/100g,

the storage modulus G' (60) of the colored resin particles at 60 ℃ determined by dynamic viscoelasticity measurement is 1.6X 10⁸～5.0×10⁸Pa。

The colored resin particles constituting the toner according to aspect 2 of the present invention can be produced by any of a dry method such as a pulverization method, a wet method such as an emulsion polymerization aggregation method, a dispersion polymerization method, a suspension polymerization method, and a dissolution suspension method, as in the toner according to aspect 1, and are preferably produced by a wet method in terms of easily obtaining a toner excellent in printing characteristics such as image reproducibility. In addition, when the colored resin particles constituting the toner according to aspect 2 of the present invention are produced by the suspension polymerization method (a), which is particularly preferable among the wet methods, or by the pulverization method (B), which is typical among the dry methods, the production can be performed by the same procedure as in the toner according to aspect 1.

In the case of obtaining colored resin particles constituting the toner according to aspect 2 of the present invention by (a) suspension polymerization, the colored resin particles can be produced through the steps of (a-1) a step of preparing a polymerizable monomer composition, (a-2) a suspension step (a droplet formation step) of obtaining a suspension, (a-3) a polymerization step, and (a-4) washing, filtering, dehydrating, and drying steps, as in the case of the toner according to aspect 1 described above. In this case, as the raw materials for producing the colored resin particles, such as the polymerizable monomer, the colorant, the charge control agent, the release agent, the additive having a polydiene structure, and further other additives used as necessary, the same raw materials as in the case of the toner according to the above-mentioned point 1 can be used, and the production conditions thereof can be the same.

In the case where the colored resin particles constituting the toner according to claim 2 of the present invention are obtained by the (B) pulverization method, the colored resin particles can be produced by the same method as in the case of the toner according to claim 1, and the same raw materials as in the case of the toner according to claim 1 can be used as the raw materials for producing the colored resin particles, and the production conditions can be the same.

The colored resin particles constituting the toner according to aspect 2 of the present invention can be produced by, for example, the above-mentioned (a) suspension polymerization method or (B) pulverization method, and in aspect 2 of the present invention, the storage modulus G' (60) at 60 ℃ determined by dynamic viscoelasticity measurement is controlled to 1.6 × 10⁸～5.0×10⁸Colored resin particles in the range of Pa are used as the colored resin particles. By controlling the storage modulus G' (60) of the colored resin particles at 60 ℃ determined by dynamic viscoelasticity measurement to be within the above range, blocking of the obtained toner can be effectively suppressed, and the effect of improving the low-temperature fixability by adding a release agent can be sufficiently exhibited. As a result, the obtained toner can be excellent in storage stability and low-temperature fixing property.

The storage modulus G' (60) at 60 ℃ of the colored resin particles determined by dynamic viscoelasticity measurement is 1.6X 10⁸～5.0×10⁸Pa, preferably 1.8X 10⁸～4.5×10⁸Pa, more preferably 2.0X 10⁸～4.0×10⁸Pa range.

In addition, in the aspect 2 of the present invention, the storage modulus G '(60) at 60 ℃ of the colored resin particles obtained by the dynamic viscoelasticity measurement may be in the above range, and from the viewpoint of further improving the storage stability and low-temperature fixability of the resultant toner, it is preferable that the storage modulus G' (100) at 100 ℃ of the colored resin particles obtained by the dynamic viscoelasticity measurement is controlled to be 1.0 × 10⁵～3.0×10⁵Pa, more preferably 1.1X 10⁵～2.9×10⁵The range of Pa is more preferably controlled to 1.2X 10⁵～2.8×10⁵Pa range.

The ratio G '(60)/G' (100) of the storage modulus G '(60) at 60 ℃ to the storage modulus G' (100) at 100 ℃ of the colored resin particles determined by the dynamic viscoelasticity measurement is not particularly limited, and is preferably controlled to 1.0 × 10 from the viewpoint of further improving the storage stability and low-temperature fixability of the resulting toner³～5.0×10³More preferably 1.0X 10³～4.0×10³More preferably, the range of (1.0X 10)³～3.0×10³The range of (1).

The method for measuring storage modulus G '(60) at 60 ℃ and storage modulus G' (100) at 100 ℃ of the colored resin particles is not particularly limited, and can be determined by the following method: will be atWith colored resin particles (in the case of colored resin particles in the resin composition) held between a pair of plates by a load of 20gIn a state in which the areas of the colored resin particles are uniformly arranged, the colored resin particles are held between a pair of plates by a load of 20 g) as a measurement sample, and the dynamic viscoelasticity is measured in a range of 45 to 150 ℃ by a dynamic viscoelasticity measuring apparatus using a rotary flat type rheometer under conditions in which the measurement frequency is 24Hz and the temperature rise rate is 5 ℃/min.

In addition, in the invention of claim 2The method of setting the storage modulus G '(60) at 60 ℃ of the colored resin particles and the storage modulus G' (100) at 100 ℃ of the colored resin particles in the above ranges is not particularly limited, and a method of adding an additive having a polydiene structure to the colored resin particles may be mentioned. Specifically, by containing the additive having a polydiene structure, the release agent can be dispersed in the colored resin particles appropriately by utilizing the compatibility of the additive having a polydiene structure with the release agent, and thus the storage modulus G '(60) of the colored resin particles at 60 ℃ and the storage modulus G' (100) of the colored resin particles at 100 ℃ can be made to fall within the above range. In addition, in the invention of claim 1, the colored resin particles are further controlled to have a storage modulus G' (60) at 60 ℃ of 1.6X 10⁸～5.0×10⁸The method within Pa is not particularly limited, and may be a method of adjusting the type of the additive having a polydiene structure to be used, the type of the release agent to be used, the amount of the additive having a polydiene structure to be used, and the amount of the release agent to be used, and the like, or may be a combination thereof. Similarly, the storage modulus G' (100) of the colored resin particles at 100 ℃ was further controlled to be 1.0X 10⁵～3.0×10⁵The method within Pa is not particularly limited, and may be a method of adjusting the type of the additive having a polydiene structure to be used, the type of the release agent to be used, the amount of the additive having a polydiene structure to be used, and the amount of the release agent to be used, and the like, or may be a combination thereof.

The volume average particle diameter (Dv), number average particle diameter (Dn), particle diameter distribution (Dv/Dn), and average circularity of the colored resin particles are preferably in the same ranges for the same reasons as those of the colored resin particles in the above-mentioned viewpoint 1.

The gel content (tetrahydrofuran insoluble matter content) and the weight average molecular weight (Mw) of the colored resin particles are also preferably in the same ranges for the same reasons as those of the colored resin particles in the above-mentioned viewpoint 1.

The colored resin particles described above may be used as a toner as they are or as a toner by mixing carrier particles (ferrite, iron powder, etc.) with the colored resin particles, and in order to adjust the charging property, fluidity, storage property, etc. of the toner, a high-speed Mixer (for example, FM Mixer (trade name, Nippon Coke & Engineering co., ltd.) or the like) may be used, and external additives may be added/mixed to the colored resin particles to prepare a single-component toner, and further, the colored resin particles and the external additives may be mixed and the carrier particles may be further mixed to prepare a two-component toner. As the stirrer for the external addition treatment, the same stirrer as in the above-described aspect 1 can be used, and as the external additive, the same external additive as in the above-described aspect 1 can be used in the same ratio.

The toner according to claim 2 of the present invention uses, as colored resin particles, colored resin particles containing a binder resin, a colorant, a charge control agent, a release agent, and an additive having a polydiene structure and having a solubility in styrene at 40 ℃ of 3 to 40G/100G, wherein the storage modulus G' (60) of the colored resin particles at 60 ℃ determined by dynamic viscoelasticity measurement is controlled to be 1.6 × 10⁸～5.0×10⁸The range of Pa is excellent in storage stability and low-temperature fixability with the toner according to claim 2 of the present invention, and therefore can sufficiently meet recent demands for reduction in energy consumption and increase in printing speed.

Examples

The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. Unless otherwise specified, "part(s)" and "%" are based on mass.

The test methods performed in the present example and comparative example are as follows.

(1) Weight average molecular weight of conjugated diene-aromatic vinyl thermoplastic elastomer

The molecular weight was determined as a polystyrene equivalent molecular weight by high performance liquid chromatography using tetrahydrofuran as a carrier at a flow rate of 0.35 ml/min. The apparatus used HLC8220 manufactured by Tosoh Corporation, the column used 3-linked Shodex (registered trademark) KF-404HQ (column temperature 40 ℃ C.) manufactured by Showa Denko Group, the detector used a differential refractometer and an ultraviolet detector, and the correction of molecular weight was carried out at 12 points of standard polystyrene (from 500 to 300 ten thousand) manufactured by Polymer Laboratories Ltd.

(2) Content of each block copolymer in the conjugated diene-aromatic vinyl thermoplastic elastomer

The peak area ratio was determined from the area ratio of the peak corresponding to each block copolymer in the graph obtained by the high performance liquid chromatograph.

(3) Weight average molecular weight of styrene polymer block constituting block copolymer of conjugated diene-aromatic vinyl-based thermoplastic elastomer

The isoprene polymer blocks of the block copolymer were decomposed by reacting the block copolymer with ozone and reducing it with lithium aluminum hydride according to the method described in Rubber chem.technol.,45,1295 (1972). Specifically, the procedure was as follows. That is, 300mg of a sample was dissolved in a reaction vessel containing 100ml of molecular sieve-treated methylene chloride. After the reaction vessel was placed in a cooling tank to-25 ℃, ozone generated by an ozone generator was introduced while oxygen was flowed through the reaction vessel at a flow rate of 170 ml/min. After 30 minutes had elapsed from the start of the reaction, the termination of the reaction was confirmed by introducing the gas flowing out of the reaction vessel into an aqueous potassium iodide solution. Next, 50ml of diethyl ether and 470mg of lithium aluminum hydride were added to another reaction vessel subjected to nitrogen substitution, and a solution reacted with ozone was slowly dropped into the reaction vessel while cooling the reaction vessel with ice water. The reaction vessel was then placed in a water bath, slowly warmed and refluxed at 40 ℃ for 30 minutes. Then, a small amount of dilute hydrochloric acid was added dropwise to the reaction vessel while stirring the solution, and the dropwise addition was continued until generation of hydrogen was hardly observed. After the reaction, a solid product formed in the solution was separated by filtration, and the solid product was extracted with 100ml of diethyl ether for 10 minutes. The extract was combined with the filtrate at the time of filtration, and the solvent was distilled off, thereby obtaining a solid sample. The weight average molecular weight of the thus-obtained sample was measured in accordance with the above-mentioned method for measuring the weight average molecular weight, and the value was defined as the weight average molecular weight of the styrene polymer block.

(4) Weight average molecular weight of isoprene polymer block constituting block copolymer of conjugated diene-aromatic vinyl-based thermoplastic elastomer

The weight average molecular weight of the corresponding styrene polymer block determined as described above is subtracted from the weight average molecular weight of the block copolymer determined as described above, and the weight average molecular weight of the isoprene polymer block is determined based on the calculated value.

(5) Styrene unit content of Block copolymer constituting conjugated diene-aromatic vinyl-based thermoplastic elastomer

The measurement intensity is determined based on the detection intensity ratio between the differential refractometer and the ultraviolet detector in the measurement by the high performance liquid chromatograph. In addition, copolymers having different styrene unit contents were prepared in advance, and a calibration curve was prepared using them.

(6) Vinyl bond content of isoprene polymer block constituting block copolymer of conjugated diene-aromatic vinyl-based thermoplastic elastomer

Determined by proton NMR measurement.

(7) Styrene unit content of conjugated diene-aromatic vinyl thermoplastic elastomer

Determined by proton NMR measurement.

(8) Melt index of conjugated diene-aromatic vinyl thermoplastic elastomer

The measurement was carried out according to ASTM D1238(G condition, 200 ℃ C., 5kg load).

(9) Volume average particle diameter (Dv) of colored resin particles

About 0.1g of the colored resin particles were weighed out into a beaker, and 0.1mL of a surfactant solution (manufactured by FUJIFILM Corporation, trade name: Drywell) as a dispersant was added. 10 to 30mL of Isoton II was further added to the beaker, and after dispersing for 3 minutes using a 20W ultrasonic disperser, the resulting mixture was measured by a particle size measuring machine (Beckman COULTER CO., manufactured by Ltd., trade name: Multisizer) in a pore diameter: 100 μm, medium: isoton II, number of particles determined: the volume average particle diameter (Dv) of the colored resin particles was measured under conditions of 100000 pieces.

(10) Gel content of colored resin particles

1.0g of the colored resin particles were weighed and added to a Soxhlet extractor placed in a cylindrical filter paper (manufactured by Cybernavi Inc.: No.86R, size 28X 100mm), and 100ml of Tetrahydrofuran (THF) was used as a solvent to reflux for 5 hours to obtain an extract. THF was distilled off from the extract to obtain a nonvolatile fraction, which was dried under vacuum at 50 ℃ for 1 hour, and then finely weighed according to the following calculation formula.

THF insoluble matter content (%) [ (T-S)/(T) ] × 100

T: sample amount (g) of colored resin particles

S: amount of non-volatile component (g) extracted

(11) Weight average molecular weight (Mw) of colored resin particles

0.1g of the finely weighed colored resin pellets were put into 100mL glass sample bottles, and 49.9g of Tetrahydrofuran (THF) was added thereto. Subsequently, a stirrer was placed, and the mixture was stirred at room temperature for 1 hour with a magnetic stirrer, and then filtered with a 0.2 μm PTFE filter to obtain a THF solution of colored resin particles. Finally, 100. mu.L of each THF solution was injected into the GPC measurement apparatus. The weight average molecular weight (Mw) was converted based on the GPC elution curve obtained from a calibration curve obtained from a commercially available monodisperse standard polystyrene.

(GPC measurement conditions)

GPC: HLC-8220 (manufactured by Tosoh Corporation)

Column: 2 TSK-GEL MULTIPORE HXL-M (manufactured by Tosoh Corporation) connected in series

Eluent: THF (tetrahydrofuran)

Flow rate: 1.0 mL/min

Temperature: 40 deg.C

(12) Melting temperature of colored resin particles (T1/2)

The melting temperature (T1/2) of the colored resin particles by 1/2 method was calculated from the melt viscosity using a flow meter. Specifically, the melt viscosity was measured using a flow meter (product name: CFT-500C, manufactured by Shimadzu Corporation) under conditions of a predetermined starting temperature, temperature rising rate, preheating time, and shear stress. Then, from the obtained melt viscosity, the melting temperature (T1/2) was determined by the method 1/2.

Measurement start temperature: temperature rise rate at 40 ℃: 3 ℃/min, preheating time: 5 minutes, cylinder pressure: 10kgf/cm²The diameter of the die is as follows: 0.5mm, die length: 1.0mm

(13) The average aspect ratio, average major axis, average minor axis and aspect ratio of the domains of the mold release agent are within the range of 2 to 10, and the number of domains of the mold release agent with the aspect ratio within the range of 3 to 8

The colored resin particles were dispersed in an epoxy resin and solidified, and after cooling to a temperature of-80 ℃, the resin particles were cut with a slicer to prepare a thin sheet. Then, the prepared thin section was dyed with 0.5% ruthenium tetroxide aqueous vapor for about 5 minutes, and the dyed thin section was observed with a Transmission Electron Microscope (TEM). In addition, when preparing the thin slice as the measuring sample, the concentration of the colored resin particles in the thin slice is prepared to be the concentration which can observe 5-10 sections in the range of 28 μm multiplied by 35 μm (multiplying power of 5000-6000 times). Then, a measurement image in a field of view of 28 μm × 35 μm was obtained, and in the obtained measurement image, colored resin particles not shown in the whole image of the cross section of the colored resin particles and colored resin particles outside the range of 0.6 to 1.2 times the volume average particle diameter (Dv) were excluded from the evaluation, and 5 or more colored resin particles were specified as evaluation objects. Then, the number of domains of the release agent of the specified colored resin particles, the aspect ratio of the domains of the release agent, the major axis and the minor axis are calculated by image analysis, and the average value of the aspect ratio of the domains of the release agent, the average major axis and the average minor axis, and the number of domains of the release agent having an aspect ratio in the range of 2 to 10 in the field of view of 2 μm × 2 μm square and the number of domains of the release agent having an aspect ratio in the range of 3 to 8 are obtained using the calculated results. The number of the crystal domains of the release agent having an aspect ratio in the range of 2 to 10 and the number of the crystal domains of the release agent having an aspect ratio in the range of 3 to 8 are calculated based on the above calculation result in terms of the number of the crystal domains in the visual field of 2 μm × 2 μm square.

(14) Storage modulus G '(60) at 60 ℃ and storage modulus G' (100) at 100 ℃ of the colored resin particles

Will be atThe pair of plates (parallel plates or cross plates) of (A) sandwiching the colored resin particles (in the case of the colored resin particles in the case of a load of 20gThe colored resin particles are placed in a uniform area, and the sample is measured as a dynamic viscoelasticity measurement device (product name "ARES-G2", manufactured by TA instruments) using a rotary flat type rheometer under conditions of a measurement frequency of 24Hz and a load of 20G, at a temperature rise rate of 5 ℃/min and in a range of 45 to 150 ℃.

(15) Evaluation of storage Properties of toner

After a toner (10 g) was put into a 100mL polyethylene container and sealed, the container was immersed in a constant temperature water tank set at a predetermined temperature and taken out after 8 hours. The toner was transferred from the take-out container to a 42-mesh sieve without giving vibration as much as possible, and set in a Powder measuring machine (product name: Powder Tester PT-R, manufactured by Hosokawa Micron Group). The amplitude of the sieve was set to 1.0mm, and after the sieve was vibrated for 30 seconds, the mass of the toner remaining on the sieve was measured and taken as the mass of the aggregated toner. The maximum temperature (. degree. C.) at which the mass of the aggregated toner becomes 0.5g or less was set as a storage temperature, which was used as an index of storage.

(16) Minimum fixing temperature of toner

A commercially available printer of a nonmagnetic monocomponent development system (printing speed 20ppm) was modified so that the temperature of the fixing roller portion could be changed, and a fixing test was performed using this printer. The fixing test was performed as follows: the temperature-fixing ratio relationship was determined by performing full black (printing density 100%) printing, changing the temperature of the fixing roller of the modified printer at 5 ℃ intervals, and measuring the fixing ratio of the toner at each temperature. Tape separation was performed in a printing region of full black (printing density 100%), and the fixing ratio was calculated from the ratio of the image density before and after tape separation. That is, when the image density before the tape is peeled is ID (front) and the image density after the tape is peeled is ID (rear), the fixing ratio can be calculated by the following calculation formula.

Fixing ratio (%) (ID (post)/ID (pre)) × 100

The Tape peeling operation is a series of operations of sticking an adhesive Tape (trade name: Scotch bonding Tape 810-3-18, manufactured by Sumitomo 3M Limited) to a measurement portion of the test paper, pressing the Tape under a constant pressure to adhere the Tape, and peeling the Tape in the direction of the paper at a constant speed. Further, the image density was measured using a reflection type image density meter (manufactured by Macbeth Corporation, trade name: RD 914).

In this fixing test, the lowest fixing roller temperature at which the fixing ratio exceeds 80% is set as the lowest fixing temperature of the toner.

(17) Temperature at which thermal offset of toner occurs

A commercially available printer of a nonmagnetic monocomponent development system (printing speed 20ppm) was modified so that the temperature of the fixing roller portion could be changed, and a thermal offset test was performed using this printer. The thermal offset test was performed as follows: the temperature of the fixing roller portion was changed from 150 ℃ to 220 ℃ at 5 ℃ intervals, and a 5cm square all black image was printed on paper (manufactured by Xerox Corporation, trade name: vitality), and it was visually observed whether or not fusion of the toner occurred on the fixing roller, and a non-offset phenomenon was observed.

In this thermal offset test, the lowest set temperature at which toner fusion occurs on the fixing roller is set as the thermal offset occurrence temperature.

(18) Charge amount of toner

Regarding the charge amount (μ C/g) of the toner, an ink cartridge filled with the toner left for 1 day in an environment of normal temperature and normal humidity (23 ℃ and 50% RH) was mounted in a commercially available printer of a nonmagnetic single component development system (printing speed 20ppm), and evaluated in an environment of normal temperature and normal humidity (23 ℃ and 50% RH). First, 2 sheets of the toner were printed in full white, and then the charge amount (μ C/g) of the toner adhering to the developing roller was measured by a suction type charge amount measuring device (product name: 210HS-2A, manufactured by TREK JAPAN). The charge amount of the toner was evaluated in examples 4-1 to 4-4 and comparative examples 4-1 to 4-3.

(19) Rate of leaching

The toner was stored at 40 ℃ for 30 days, and the bleeding rate of the stored toner was measured. Specifically, the toner after 30 days of storage was observed by SEM, and the presence or absence of bleeding of the release agent was evaluated for about 100 toner particles, and the ratio of the toner particles in which bleeding occurred was taken as the bleeding rate (% by unit). The evaluation of the leaching rates was carried out for examples 4-1 to 4-4 and comparative examples 4-1 to 4-3.

(20) Evaluation of discharge

After filling toner in a toner cartridge of a developing device using a commercially available printer of a nonmagnetic single-component developing system (printing speed 20ppm), the toner cartridge filled with toner was left at 40 ℃ for 30 days, and then the toner cartridge taken out was mounted in the printer at a temperature of: 32.5 ℃, humidity: continuous printing was performed under 80% conditions. Printing was performed at a halftone image density of 30%. Then, after the start of continuous printing, the presence or absence of toner ejection from the toner cartridge to the printing paper (the presence or absence of a patch of 0.3 × 0.3mm or more due to toner in halftone) was checked every 1 hour. It is considered that the longer the period of time in which the toner cartridge is not confirmed to eject toner onto the printing paper, the higher the ejection suppression effect. The ejection was evaluated for examples 4-1 to 4-4 and comparative examples 4-1 to 4-3.

(21) Scraper attachment

After filling a toner in a toner cartridge of a developing device using a commercially available printer of a nonmagnetic single-component developing system (printing speed 20ppm), the toner cartridge filled with the toner was left at 40 ℃ for 30 days, and then whether or not an adhering substance was adhered to a blade (a blade defining a toner layer) was confirmed. The evaluation of the blade deposit was carried out for examples 4-1 to 4-4 and comparative examples 4-1 to 4-3.

Production example 1

23.2kg of cyclohexane, 1.5 mmol of N, N, N ', N' -tetramethylethylenediamine (hereinafter referred to as TMEDA) and 1.70kg of styrene were charged into a pressure-resistant reactor, and 99.1 mmol of N-butyllithium was added thereto while stirring at 40 ℃ to raise the temperature to 50 ℃ and polymerize the mixture for 1 hour. The polymerization conversion of styrene was 100 mass%. Then, 6.03kg of isoprene was continuously added to the reactor over 1 hour while controlling the temperature so as to be maintained at 50 to 60 ℃. After the addition of isoprene was completed, polymerization was further carried out for 1 hour to obtain a styrene-isoprene diblock copolymer B (copolymer B represented by Ar-D). The polymerization conversion of isoprene was 100%. Next, 15.0 mmol of dichlorodimethylsilane as a coupling agent was added to conduct a coupling reaction for 2 hours, to form a styrene-isoprene-styrene triblock copolymer (copolymer a represented by Ar-D-Ar). Then, 198 mmol of methanol as a polymerization terminator was added thereto, and the reaction mixture was thoroughly mixed to terminate the reaction, thereby obtaining a reaction solution containing the block copolymer composition (. alpha.1). A part of the obtained reaction liquid was taken out, and the weight average molecular weight, content ratio and vinyl bond content of each block copolymer and the whole block copolymer composition were determined. The results obtained are shown in Table 1. Then, 0.3 part of 2, 6-di-t-butyl-p-cresol as an antioxidant was added to 100 parts of the thus-obtained reaction solution (containing 30 parts of the polymer component) and mixed, the mixed solution was added dropwise in a small amount to warm water heated to 85 to 95 ℃ to volatilize the solvent to obtain precipitates, the precipitates were pulverized and dried with hot air at 85 ℃, thereby recovering the block copolymer composition (. alpha.1). The melt index of the obtained block copolymer composition (. alpha.1) was measured, and the results are shown in Table 2. The obtained block copolymer composition (. alpha.1) was measured for its solubility in styrene at a temperature of 40 ℃ and found to be 20g/100 g.

Production example 2

A block copolymer composition (α 2) of production example 2 was obtained in the same manner as in production example 1, except that the amounts of styrene, n-butyllithium, TMEDA, isoprene, dichlorodimethylsilane and methanol were changed as shown in table 1, respectively, and the measurement was performed in the same manner. The measurement results are shown in Table 2. The solubility in styrene at a temperature of 40 ℃ was measured for the obtained block copolymer composition (. alpha.2), and it was found to be 20g/100 g.

Production example 3

A block copolymer composition (α 3) of production example 3 was obtained in the same manner as in production example 1, except that the amounts of styrene, n-butyllithium, TMEDA, isoprene, dichlorodimethylsilane and methanol were changed as shown in table 1, respectively, and the measurements were performed in the same manner. The measurement results are shown in Table 2. The solubility in styrene at a temperature of 40 ℃ was measured for the obtained block copolymer composition (. alpha.3), and it was found to be 20g/100 g.

Production example 4

A block copolymer composition (α 4) of production example 4 was obtained in the same manner as in production example 1, except that the amounts of styrene, n-butyllithium, TMEDA, isoprene, dichlorodimethylsilane and methanol were changed as shown in table 1, respectively, and the measurements were performed in the same manner. The measurement results are shown in Table 2. Further, the solubility in styrene at a temperature of 40 ℃ was measured for the obtained block copolymer composition (. alpha.4), and it was found to be 4g/100 g.

Production example 5

A block copolymer composition (α 5) of production example 5 was obtained in the same manner as in production example 1, except that the amounts of styrene, n-butyllithium, TMEDA, isoprene and methanol were changed as shown in table 1, and tetramethoxysilane was used in an amount shown in table 1 in place of dichlorodimethylsilane, respectively, and the measurement was performed in the same manner. The measurement results are shown in Table 2. The block copolymer composition (. alpha.5) obtained in production example 5 contained a styrene-isoprene diblock copolymer B (copolymer B represented by Ar-D) and a 3-branched styrene-isoprene block copolymer C (copolymer B represented by (Ar-D))₃The copolymer C represented by X) and a 4-branched styrene-isoprene block copolymer D (represented by (Ar-D)₄The copolymer D) represented by X. Further, the solubility in styrene at a temperature of 40 ℃ was measured for the obtained block copolymer composition (. alpha.5), and it was found to be 2g/100 g.

Production example 6 and production example of acrylic resin

After 200 parts of toluene was put into a reaction vessel, the toluene was stirred and the inside of the reaction vessel was sufficiently replaced with nitrogen, the temperature was raised to 90 ℃ and a mixed solution of 95 parts of methyl methacrylate, 4.6 parts of n-butyl acrylate, 0.4 part of acrylic acid and 2.8 parts of tert-butyl peroxy-2-ethylhexanoate (trade name: PERBUTYL O, manufactured by NOF CORPORATION) was added dropwise to the reaction vessel over 2 hours. Further, the polymerization was terminated by keeping the mixture under toluene reflux for 10 hours, and then the solvent was distilled off under reduced pressure. Thus, an acrylic resin (Tg70 ℃, acid value 2.5, weight average molecular weight (Mw)11000) was obtained.

[ Table 1]

TABLE 1

[ Table 2]

TABLE 2

[ example 1-1]

77 parts of styrene and 23 parts of n-butyl acrylate as monovinyl monomers, 7 parts of carbon black (product name: #25B manufactured by Mitsubishi Chemical Corporation) as a colorant, 0.6 part of divinylbenzene as a crosslinkable polymerizable monomer, 1.2 parts of t-dodecyl mercaptan as a molecular weight regulator, 0.3 part of polymethacrylate macromonomer (TOAGOSEI CO., manufactured by Ltd., product name: AA6, Tg 94 ℃ C.) as a macromonomer, and 1 part of the acrylic resin obtained in production example 2 were subjected to wet pulverization using a media type wet pulverizer, and 1 part of a charge control resin (styrene/acrylic resin containing a quaternary ammonium salt as a functional group, monomer containing a quaternary ammonium salt as a functional group) as a charge control agent, copolymerization ratio of 2 parts of behenyl stearate (number average molecular weight (Mn) 592) as a release agent, and 5 parts of production example 1 as an additive having a polydiene structure were added thereto The obtained block copolymer composition (. alpha.1) was mixed to obtain a polymerizable monomer composition.

On the other hand, in a stirred tank, an aqueous solution of 7.4 parts of magnesium chloride (water-soluble polyvalent metal salt) dissolved in 250 parts of ion-exchanged water was slowly added to an aqueous solution of 4.1 parts of sodium hydroxide (alkali metal hydroxide) dissolved in 50 parts of ion-exchanged water with stirring at room temperature to prepare a dispersion of magnesium hydroxide colloid (metal hydroxide colloid which is hardly soluble in water).

On the other hand, 2 parts of methyl methacrylate as a polymerizable monomer for shell and 65 parts of ion-exchanged water were subjected to microdispersion treatment by an ultrasonic emulsifier to obtain an aqueous dispersion of the polymerizable monomer for shell.

The polymerizable monomer composition was added to the colloidal dispersion of magnesium hydroxide obtained above, and stirred until the droplets were stabilized, and 6 parts of tert-butyl peroxyisobutyrate (trade name: PERBUTYL IB, manufactured by NOF Corporation) as a polymerization initiator was added thereto, and then stirred at a high shear rate of 15000rpm using an in-line emulsion disperser (trade name: Miller, manufactured by Pacific Machinery & Engineering Co., Ltd.) to circulate and disperse the mixture to form droplets of the polymerizable monomer composition.

Subsequently, 1 part of sodium tetraborate decahydrate was added to the aqueous dispersion of the polymerizable monomer composition having formed droplets, the mixture was placed in a reactor equipped with a stirring blade, the temperature was raised to 85 ℃ to carry out polymerization reaction, and after the polymerization conversion rate reached almost 100%, the aqueous dispersion of the polymerizable monomer for shell prepared above and 0.3 part of 2,2' -azobis (2-methyl-N- (2-hydroxyethyl) -propionamide) (product name: VA-086, manufactured by FUJIFILM Wako Pure Chemical Corporation) as a polymerization initiator for shell were added to the reactor. Further, the polymerization was continued for 4 hours, and then the reaction was terminated by cooling with water to obtain an aqueous dispersion of the core-shell-structured colored resin particles.

The aqueous dispersion of the colored resin particles is washed (25 ℃ C., 10 minutes) with dilute sulfuric acid to have a pH of 4.5 or less. Next, after separating the water by filtration, 200 parts of ion-exchanged water was added again to form a slurry again, the water washing treatment (washing/filtration/dehydration) was repeated several times at room temperature (25 ℃), and the obtained solid content was separated by filtration and then dried under vacuum to obtain dried colored resin particles. The obtained colored resin particles were measured by the above-mentioned methods, respectively, for the average aspect ratio of the domains containing the release agent, the average major axis, the average minor axis, the number of domains containing the release agent having an aspect ratio in the range of 2 to 10, the number of domains containing the release agent having an aspect ratio in the range of 3 to 8, the storage modulus G '(60) at 60 ℃, and the storage modulus G' (100) at 100 ℃. The results are shown in Table 3.

Further, to 100 parts of the colored resin particles obtained as described above, 0.5 part of silica fine particles having a number average primary particle diameter of 7nm hydrophobized with a cyclic silazane and 1 part of silica fine particles having a number average primary particle diameter of 35nm hydrophobized with an amino-modified silicone oil were added as external additives, and the mixture was stirred and mixed with a high-speed Mixer (Nippon cake & Engineering Co., Ltd., trade name: FM Mixer) to carry out an external addition treatment, thereby producing a toner for developing electrostatic images. The obtained toner for developing electrostatic images was used to perform the above-described various measurements. The results are shown in Table 2.

[ examples 1-2]

The same procedures used in example 1-1 were repeated except that 20 parts of stearyl stearate (number average molecular weight (Mn): 536) was used in place of 20 parts of behenyl stearate as a release agent, to obtain colored resin particles and an electrostatic image developing toner of example 1-2, and the evaluations were performed in the same manner. The results are shown in Table 3.

[ examples 1 to 3]

The same procedures used in examples 1-1 were repeated except that 20 parts of behenyl behenate (number average molecular weight (Mn): 648) was used instead of 20 parts of behenyl stearate as a release agent, to obtain colored resin particles and electrostatic image developing toners of examples 1-3, and the evaluations were performed in the same manner. The results are shown in Table 3.

[ examples 1 to 4]

The same procedures as in example 1-1 were repeated except for using 1.7 parts of solution-polymerized polyisoprene rubber 1 (trade name "KURAPERE LIR-30", manufactured by Kuraray Co., Ltd., weight-average molecular weight (Mw): 28000, solubility in styrene at a temperature of 40 ℃ C.: 16g/100g) as an additive having a polydiene structure in place of 5 parts of the block copolymer composition (. alpha.1) obtained in production example 1 to obtain colored resin particles and a toner for electrostatic image development of examples 1-4, and the evaluation was performed in the same manner. The results are shown in Table 3.

[ examples 1 to 5]

The colored resin particles and the electrostatic image developing toner of examples 1 to 5 were obtained in the same manner as in example 1-1 except that the amount of the block copolymer composition (. alpha.1) as an additive having a polydiene structure was changed from 5 parts to 2 parts, and the evaluation was performed in the same manner. The results are shown in Table 3.

[ examples 1 to 6]

The colored resin particles and the electrostatic image developing toner of examples 1 to 6 were obtained in the same manner as in example 1-1 except that the amount of the block copolymer composition (. alpha.1) as an additive having a polydiene structure was changed from 5 parts to 10 parts, and the evaluation was performed in the same manner. The results are shown in Table 3.

Comparative examples 1 to 1

The same procedures as in example 1-1 were repeated except that the block copolymer composition (. alpha.1) as an additive having a polydiene structure was not blended, to obtain colored resin particles and an electrostatic image developing toner of comparative example 1-1, and the evaluation was performed in the same manner. The results are shown in Table 3.

Comparative examples 1 and 2

The same procedures as in comparative example 1-1 were repeated except that 20 parts of behenyl behenate (number average molecular weight (Mn): 648) was used instead of 20 parts of behenyl stearate as a release agent, to obtain colored resin particles and electrostatic image developing toner of comparative example 1-2, and the evaluations were performed in the same manner. The results are shown in Table 3.

Comparative examples 1 to 3

The same procedures as in example 1-1 were repeated except for using 1.7 parts of solution-polymerized polyisoprene rubber 2 (trade name: IR2200, manufactured by Raynaud corporation, Japan, weight-average molecular weight (Mw): 1100000, solubility in styrene at 40 ℃ C.: 2.4g/100g) as an additive having a polydiene structure in place of 5 parts of the block copolymer composition (. alpha.1) obtained in production example 1, to obtain colored resin particles and a toner for electrostatic image development of comparative examples 1-3, and the evaluation was performed in the same manner. The results are shown in Table 3.

[ Table 3]

[ evaluation of examples 1-1 to 1-6 and comparative examples 1-1 to 1-3]

As shown in Table 3, the number of domains of the release agent having an aspect ratio in the range of 2 to 10 in a field of view of 2. mu. m.times.2 μm square of a cross section observed by a Transmission Electron Microscope (TEM) using an additive having a polydiene structure and containing a binder resin, a colorant, a charge control agent, a release agent and styrene having a solubility in styrene at 40 ℃ of 3 to 40G/100G is 2 to 30, and the storage modulus G' (60) at 60 ℃ is 1.6. times.10⁸～5.0×10⁸The toners of examples 1-1 to 1-6, in which the colored resin particles of Pa were obtained as the colored resin particles, had high storage temperature, excellent storage stability, low minimum fixing temperature, and excellent low-temperature fixing property. In examples 1-1 to 1-6, the temperature at which thermal offset occurs was high, and the hot offset resistance was excellent.

On the other hand, the toners of comparative examples 1-1 to 1-3, which were obtained using colored resin particles containing no additive having a polydiene structure and having a solubility in styrene at 40 ℃ of 3 to 40g/100g and having an aspect ratio in the range of 2 to 10 and having less than 2 crystal domains, had low storage temperature and poor storage stability.

Fig. 1(a) is a photograph of a cross section of the colored resin particles in example 1-1 taken with a Transmission Electron Microscope (TEM), and fig. 1(B) is a photograph of a cross section of the colored resin particles in comparative example 1-1 taken with a Transmission Electron Microscope (TEM). In contrast to examples 1-1 to 1-6 in which the domains of the release agent having an aspect ratio in the range of 2 to 10 are finely dispersed in the colored resin particles as shown in fig. 1(a) (as are examples 2-1 to 2-2, 3-1 to 3-7, and 4-1 to 4-4 described later), in comparative examples 1-1 to 1-3 in which the release agent is localized near the center of the colored resin particles (near a position slightly lower to the center) as shown in fig. 1(B), a large domain structure is formed.

[ example 2-1]

The same procedures as in example 1-1 were repeated except that the amount of divinylbenzene used was changed from 0.6 parts to 0.3 parts, to obtain colored resin particles and electrostatic image developing toner of example 2-1, and the evaluation was performed in the same manner. The results are shown in Table 4.

[ examples 2-2]

The same procedures as in example 2-1 were repeated except that the amount of divinylbenzene used was changed from 0.3 parts to 0.33 parts, to obtain colored resin particles and electrostatic image developing toner of example 2-2, and the evaluations were performed in the same manner. The results are shown in Table 4.

Comparative example 2-1

The same procedures as in example 2-1 were repeated except that the amount of divinylbenzene used was changed from 0.3 parts to 0.51 parts and the block copolymer composition (. alpha.1) as an additive having a polydiene structure was not blended, to obtain colored resin particles and an electrostatic image developing toner of comparative example 2-1, and the evaluation was performed in the same manner. The results are shown in Table 4.

Comparative examples 2 and 2

The same procedures as in example 2-1 were repeated except that the amount of divinylbenzene used was changed from 0.3 parts to 0.54 parts and the block copolymer composition (. alpha.1) as an additive having a polydiene structure was not blended, to obtain colored resin particles and an electrostatic image developing toner of comparative example 2-2, and the evaluation was performed in the same manner. The results are shown in Table 4.

Comparative examples 2 to 3

The same procedures as in example 2-1 were repeated except that the amount of divinylbenzene used was changed from 0.3 parts to 0.6 parts and 5 parts of a styrene-ethylene/propylene-styrene block copolymer (trade name: SEPTON 2104, styrene unit content: 65 mass%, weight average molecular weight (Mw): 64000, solubility in styrene at a temperature of 40 ℃ C.: 15g/100g) was used instead of 5 parts of the block copolymer composition (. alpha.1) as an additive having a polydiene structure, to obtain colored resin particles and a toner for electrostatic image development of comparative examples 2-3, and the evaluation was performed in the same manner. The results are shown in Table 4.

Comparative examples 2 to 4

The same procedures as in example 2-1 were repeated except that the amount of divinylbenzene used was changed from 0.3 parts to 0.6 parts, and 5 parts of a styrene-ethylene/propylene-styrene block copolymer (trade name: SEPTON 4033, manufactured by Kuraray Co., Ltd., product name: SEPTON 4033, styrene unit content: 30 mass%, weight average molecular weight (Mw): 81000, solubility in styrene at a temperature of 40 ℃ C.: 15g/100g) was used instead of 5 parts of the block copolymer composition (. alpha.1) as an additive having a polydiene structure, to obtain colored resin particles and a toner for electrostatic image development of comparative examples 2-4, and the evaluation was performed in the same manner as in example 2-1. The results are shown in Table 4.

[ Table 4]

[ evaluation of examples 2-1 to 2-2 and comparative examples 2-1 to 2-4]

As shown in Table 4, the number of domains of the release agent having an aspect ratio in the range of 2 to 10 in a field of view of 2. mu. m.times.2 μm square of a cross section observed by a Transmission Electron Microscope (TEM) using an additive having a polydiene structure and containing a binder resin, a colorant, a charge control agent, a release agent and styrene having a solubility in styrene at 40 ℃ of 3 to 40G/100G is 2 to 30, and the storage modulus G' (60) at 60 ℃ is 1.6. times.10⁸～5.0×10⁸The toners of examples 2-1 to 2-2, in which the colored resin particles of Pa were obtained as the colored resin particles, had high storage temperature, excellent storage stability, low minimum fixing temperature, and excellent low-temperature fixing property.

On the other hand, storage at 60 ℃ is usedEnergy modulus G' (60) less than 1.6X 10⁸The toners of comparative examples 2-1 to 2-4 obtained by coloring resin particles Pa had a low storage temperature and poor storage stability.

[ example 3-1]

The same procedures as in example 1-1 were repeated except that the amount of divinylbenzene used was changed from 0.6 parts to 0.45 parts, to obtain colored resin particles and electrostatic image developing toner of example 3-1, and the evaluations were performed in the same manner. The results are shown in Table 5.

[ examples 3-2]

The same procedures as in example 3-1 were repeated except that the amount of divinylbenzene used was changed from 0.6 parts to 0.3 parts, to obtain colored resin particles and electrostatic image developing toner of example 3-2, and the evaluations were performed in the same manner. The results are shown in Table 5.

[ examples 3 to 3]

The same procedures as in example 3-1 were repeated except that the amount of divinylbenzene used was changed from 0.45 parts to 0.6 parts and the amount of the block copolymer composition (. alpha.1) obtained in production example 1 was changed from 5 parts to 2 parts, to obtain colored resin particles and an electrostatic image developing toner of example 3-3, and the evaluations were performed in the same manner. The results are shown in Table 5.

[ examples 3 to 4]

The same procedures as in examples 3 to 3 were repeated except that the amount of divinylbenzene used was changed from 0.6 part to 0.5 part, to obtain colored resin particles and electrostatic image developing toner of examples 3 to 4, and the evaluations were performed in the same manner. The results are shown in Table 5.

[ examples 3 to 5]

The same procedures as in examples 3 to 3 were repeated except that the amount of divinylbenzene used was changed from 0.6 part to 0.4 part, to obtain colored resin particles and electrostatic image developing toner of examples 3 to 5, and the evaluation was performed in the same manner. The results are shown in Table 5.

[ examples 3 to 6]

The same procedures as in example 3-1 were repeated except that the amount of styrene used was changed from 77 parts to 83 parts, the amount of n-butyl acrylate used was changed from 23 parts to 17 parts, and the amount of divinylbenzene used was changed from 0.45 part to 0.6 part, to obtain colored resin particles and electrostatic image developing toner of examples 3-6, and the evaluations were performed in the same manner. The results are shown in Table 5.

[ examples 3 to 7]

The same procedures as in examples 3 to 3 were carried out except that the acrylic resin obtained in production example 2 was not added, and the colored resin particles and the electrostatic image developing toner of examples 3 to 7 were obtained and evaluated in the same manner. The results are shown in Table 5.

Comparative example 3-1

The same procedures as in example 3-3 were repeated except that the block copolymer composition (. alpha.1) obtained in production example 1 was not used, to obtain colored resin particles and a toner for electrostatic image development of comparative example 3-1, and the evaluations were performed in the same manner. The results are shown in Table 5.

Comparative examples 3 and 2

The colored resin particles and the toner for electrostatic image development of comparative example 3-2 were obtained in the same manner as in example 3-3 except that 2 parts of a styrene-ethylene/propylene block copolymer (Kuraray Co., Ltd., product name: SEPTON 2063, manufactured by Ltd., product name: weight average molecular weight (Mw): 91000, solubility in styrene at a temperature of 40 ℃ C.: 15g/100g) was used in place of 5 parts of the block copolymer composition (. alpha.1) obtained in production example 1, and evaluation was performed in the same manner. The results are shown in Table 5.

Comparative examples 3 to 3

The same procedures as in example 3-3 were repeated except that 5 parts of a styrene-ethylene/propylene block copolymer (product name: SEPTON 2063, manufactured by Ltd.) was used instead of 5 parts of the block copolymer composition (. alpha.1) obtained in production example 1, to obtain colored resin particles and a toner for electrostatic image development of comparative example 3-3, and the evaluation was performed in the same manner. The results are shown in Table 5.

Comparative examples 3 to 4

The same procedures as in examples 3-3 were carried out to obtain colored resin particles and electrostatic image developing toner of comparative examples 3-4, except that 2 parts of a styrene-ethylene/propylene-styrene block copolymer (product name: SEPTON 2104, manufactured by Kuraray Co., Ltd.) was used instead of 5 parts of the block copolymer composition (. alpha.1) obtained in production example 1, and the evaluations were carried out in the same manner. The results are shown in Table 5.

Comparative examples 3 to 5

The same procedures as in examples 3-3 were carried out to obtain colored resin particles and electrostatic image developing toner of comparative examples 3-5, except that 2 parts of a styrene-ethylene/propylene-styrene block copolymer (product name: SEPTON 4033, manufactured by Ltd.) was used instead of 5 parts of the block copolymer composition (. alpha.1) obtained in production example 1, and the evaluation was carried out in the same manner. The results are shown in Table 5.

[ Table 5]

[ evaluation of examples 3-1 to 3-7 and comparative examples 3-1 to 3-5]

As shown in Table 5, the number of domains of the release agent having an aspect ratio in the range of 2 to 10 in a field of view of 2. mu. m.times.2 μm square of a cross section observed by a Transmission Electron Microscope (TEM) using an additive having a polydiene structure and containing a binder resin, a colorant, a charge control agent, a release agent and styrene having a solubility in styrene at 40 ℃ of 3 to 40G/100G is 2 to 30, and the storage modulus G' (60) at 60 ℃ is 1.6. times.10⁸～5.0×10⁸The toners of examples 3-1 to 3-7, in which the colored resin particles of Pa were obtained as the colored resin particles, had high storage temperature, excellent storage stability, low minimum fixing temperature, and excellent low-temperature fixing property.

On the other hand, the toners of comparative examples 3-1 to 3-5, which did not contain an additive having a polydiene structure or used an aromatic vinyl thermoplastic elastomer having no polydiene structure and having no unsaturated bond capable of undergoing a polymerization reaction, had low storage temperature and poor storage stability. In addition, it was confirmed by the cross-sectional SEM and TEM that the toners of comparative examples 3-1 to 3-5 had a large domain structure, as a result of confirming the presence of behenyl stearate as a release agent in the toner, the behenyl stearate was localized near the center of the toner particles.

[ example 4-1]

After 70.5 parts of styrene and 29.5 parts of n-butyl acrylate as monovinyl monomers, 7 parts of carbon black (product name: #25B manufactured by Mitsubishi Chemical Corporation) as a colorant, 0.6 part of divinylbenzene as a crosslinkable polymerizable monomer, 1.2 parts of t-dodecyl mercaptan as a molecular weight regulator, 0.3 part of polymethacrylate macromonomer (TOAGOSOSEI., manufactured by Ltd., product name: AA6, Tg: 94 ℃ C.) as a macromonomer, and 1 part of the acrylic resin obtained in manufacturing example 6 were wet-pulverized using a media type wet pulverizer, 1 part of a charge control resin (styrene/acrylic resin containing a quaternary ammonium salt as a functional group, copolymerization ratio of the monomer containing the quaternary ammonium salt as a functional group: 2%), 20 parts of behenyl stearate (number average molecular weight (Mn): 592) as a release agent, and 5 parts of n-butyl acrylate (Mn): 592) as an aromatic vinyl-based thermoplastic elastomer were added The block copolymer composition (. alpha.2) obtained in example 2 was mixed to obtain a polymerizable monomer composition.

The same procedures as in example 1-1 were repeated except that the polymerizable monomer composition obtained above was used to obtain colored resin particles and an electrostatic image developing toner of example 4-1, and the evaluation was performed in the same manner. The results are shown in Table 6.

[ example 4-2]

The same procedures as in example 4-1 were repeated except for using 5 parts of the block copolymer composition (. alpha.1) obtained in production example 1 in place of 5 parts of the block copolymer composition (. alpha.2) obtained in production example 2, to obtain colored resin particles and an electrostatic image developing toner of example 4-2, and the evaluations were performed in the same manner. The results are shown in Table 6.

[ examples 4 to 3]

The same procedures as in example 4-1 were repeated except for using 5 parts of the block copolymer composition (. alpha.3) obtained in production example 3 in place of 5 parts of the block copolymer composition (. alpha.2) obtained in production example 2 to obtain colored resin particles and an electrostatic image developing toner of example 4-3, and the evaluations were performed in the same manner. The results are shown in Table 6.

[ examples 4 to 4]

The procedure of example 4-1 was repeated except that 5 parts of the block copolymer composition (. alpha.1) obtained in production example 1 was used instead of 5 parts of the block copolymer composition (. alpha.2) obtained in production example 2, and the low-molecular-weight acrylic resin obtained in production example 6 was not used, to obtain colored resin particles and an electrostatic image developing toner of example 4-4, and the evaluation was performed in the same manner. The results are shown in Table 6.

Comparative example 4-1

The same procedures as in example 4-1 were repeated except that the block copolymer composition (. alpha.2) obtained in production example 2 was not used, to obtain colored resin particles and a toner for electrostatic image development of comparative example 4-1, and the evaluations were performed in the same manner. The results are shown in Table 6.

Comparative examples 4 and 2

The same procedures as in example 4-1 were repeated except for using 5 parts of the block copolymer composition (. alpha.4) obtained in production example 4 in place of 5 parts of the block copolymer composition (. alpha.2) obtained in production example 2, to obtain colored resin particles and a toner for electrostatic image development of comparative example 4-2, and the evaluations were performed in the same manner. The results are shown in Table 6.

Comparative examples 4 to 3

The same procedures as in example 4-1 were repeated except for using 5 parts of the block copolymer composition (. alpha.5) obtained in production example 5 in place of 5 parts of the block copolymer composition (. alpha.2) obtained in production example 2 to obtain colored resin particles and a toner for electrostatic image development of comparative example 4-3, and the evaluations were performed in the same manner. The results are shown in Table 6.

[ Table 6]

As shown in table 6, the following was confirmed: the toners of examples 4-1 to 4-4, which were obtained by using, as the colored resin particles having a polydiene structure, an aromatic vinyl thermoplastic elastomer further containing a diblock copolymer comprising an aromatic vinyl polymer block and a polymer block copolymerizable with the aromatic vinyl polymer at a ratio of 40% by weight or more, had the characteristics of high storage temperature, excellent storage stability, low minimum fixing temperature, and excellent low-temperature fixability, and in addition, had high chargeability, and could suppress bleeding of a release agent, and effectively suppress ejection and adhesion to a blade under high-temperature and high-humidity conditions.

On the other hand, the toners of comparative examples 4-1 to 4-3, which used diblock copolymers containing no aromatic vinyl polymer block and no polymer block copolymerizable with the aromatic vinyl polymer, or aromatic vinyl thermoplastic elastomers having a content of the diblock copolymer of less than 40% by weight, were discharged under high-temperature and high-humidity conditions and adhered to the blade.