阅读说明：本技术 具有增强亮度的荧光品红色胶乳及由其制得的调色剂 (Fluorescent magenta latex with enhanced brightness and toner therefrom ) 是由 路春亮 P·V·纽伦 Y·齐 于 2021-02-24 设计创作，主要内容包括：本发明题为“具有增强亮度的荧光品红色胶乳及由其制得的调色剂”。本发明提供了荧光品红色胶乳,所述荧光品红色胶乳可包含水和掺有荧光剂的树脂颗粒,所述颗粒包含树脂、作为红色荧光剂的溶剂红49和作为黄色荧光剂的溶剂黄98,其中荧光品红色胶乳具有3:1至10:1范围内的溶剂红49与溶剂黄98的重量比。本发明还提供了荧光品红色调色剂以及制备和使用所述荧光品红色调色剂的方法。(The invention provides a fluorescent magenta latex with enhanced brightness and toner made therefrom. The present invention provides a fluorescent magenta latex comprising water and phosphor-doped resin particles comprising a resin, solvent red 49 as a red phosphor and solvent yellow 98 as a yellow phosphor, wherein the fluorescent magenta latex has a weight ratio of solvent red 49 to solvent yellow 98 in the range of 3:1 to 10: 1. The invention also provides fluorescent magenta toner and methods of making and using the fluorescent magenta toner.)

1. A fluorescent magenta latex comprising water and phosphor-doped resin particles comprising resin, solvent red 49 as a red phosphor and solvent yellow 98 as a yellow phosphor, wherein the fluorescent magenta latex has a weight ratio of solvent red 49 to solvent yellow 98 in the range of 3:1 to 10: 1.

2. The fluorescent magenta latex of claim 1, wherein the fluorescent magenta latex exhibits Forster Resonance Energy Transfer (FRET) upon illumination with light having a wavelength that excites the yellow fluorescent agent.

3. The fluorescent magenta latex of claim 1, further comprising a fluorescent brightener having a fluorescent emission spectrum that overlaps with an absorption spectrum of the yellow fluorescent agent.

4. The fluorescent magenta latex of claim 3, wherein the fluorescent magenta latex exhibits FRET upon irradiation with ultraviolet light.

5. The fluorescent magenta latex according to claim 3 wherein the fluorescence emission spectrum of the fluorescent whitening agent and the absorption spectrum of the yellow fluorescent agent have an overlap of 30% to 100%.

6. The fluorescent magenta latex according to claim 1, wherein the fluorescent brightener is fluorescent brightener 184.

7. The fluorescent magenta latex of claim 3 having a total amount of the red fluorescent agent, the yellow fluorescent agent, and the optical brightener in a range of 0.5 wt% to 5 wt% and a weight ratio of the optical brightener to the red and yellow fluorescent agents in a range of 1:10 to 1:0.5, based on the weight of the fluorescent magenta latex.

8. The fluorescent magenta latex of claim 1, wherein the resin is a combination of two different types of resins.

9. The fluorescent magenta latex of claim 8, wherein the two different types of resins are present in a weight ratio of 2:3 to 3: 2.

10. The fluorescent magenta latex of claim 8, wherein the two different types of resins are two amorphous polyester resins.

11. The fluorescent magenta latex of claim 10, wherein the two amorphous polyester resins are poly (propoxylated bisphenol-co-terephthalic acid-fumaric acid-dodecenyl succinate) and poly (propoxylated-ethoxylated bisphenol-co-terephthalic acid-dodecenyl succinic acid-trimellitic anhydride).

12. A fluorescent magenta toner comprising resin particles having a fluorescent agent incorporated therein, the particles comprising resin, solvent red 49 as a red fluorescent agent and solvent yellow 98 as a yellow fluorescent agent, wherein the fluorescent magenta latex has a weight ratio of solvent red 49 to solvent yellow 98 in the range of 3:1 to 10: 1.

13. The fluorescent magenta toner according to claim 12, further comprising a fluorescent brightener having a fluorescent emission spectrum that overlaps with an absorption spectrum of the yellow fluorescent agent, and wherein the fluorescent magenta toner exhibits FRET upon illumination with UV light.

14. The fluorescent magenta toner according to claim 12 further comprising a core and a shell over the core, the core comprising the fluorescent agent-doped resin particles; a crystalline polyester resin; and optionally, a wax.

15. The fluorescent magenta toner according to claim 14, wherein the core further comprises two amorphous polyester resins.

16. The fluorescent magenta toner according to claim 15, wherein the two amorphous polyester resins are poly (propoxylated bisphenol-co-terephthalic acid-fumaric acid-dodecenyl succinate) and poly (propoxylated-ethoxylated bisphenol-co-terephthalic acid-dodecenyl succinic acid-trimellitic anhydride).

17. The fluorescent magenta toner according to claim 16, wherein the crystalline polyester resin has formula I

Wherein each of a and b is in the range of 1 to 12, and p is in the range of 10 to 100.

18. The fluorescent magenta toner according to claim 17, wherein the crystalline polyester resin is poly (1, 6-hexanediol-1, 12-dodecanoate).

19. A method of making a fluorescent magenta toner, the method comprising:

forming one or more fluorescent latexes comprising solvent red 49 as a red fluorescent agent, solvent yellow 98 as a yellow fluorescent agent, a first type of amorphous resin, and a second type of amorphous resin, wherein the solvent red 49 and the solvent yellow 98 are present in a weight ratio in a range of 3:1 to 10: 1;

forming a mixture comprising: the one or more fluorescent latexes; one or more emulsions comprising a crystalline resin, the first type of amorphous resin, the second type of amorphous resin; and optionally, a wax dispersion;

aggregating the mixture to form particles of a predetermined size;

forming a shell over the predetermined size particles to form core-shell particles; and

coalescing the core-shell particles to form a fluorescent magenta toner.

20. A method of using the fluorescent magenta toner of claim 12, the method comprising:

forming an image containing the fluorescent magenta toner using a xerographic printer;

transferring an image containing the fluorescent magenta toner to an image receiving medium; and

fixing the fluorescent magenta toner to the image receiving medium.

Background

Conventional xerographic printing systems for toner applications consist of four stations, including cyan, magenta, yellow, and black (CMYK) toner stations. These and other xerographic printing systems may be made to print special colors, including fluorescent toners. A variety of fluorescent toners have been developed, but improved fluorescent toners are desired.

Disclosure of Invention

The present disclosure provides fluorescent magenta latexes and compositions, such as toners and inkjet printing compositions, formed from the fluorescent magenta latexes. Related methods are also provided.

In one aspect, a fluorescent magenta latex is provided. In an embodiment, the fluorescent magenta latex comprises water and phosphor-doped resin particles comprising a resin, solvent red 49 as the red phosphor, and solvent yellow 98 as the yellow phosphor, wherein the fluorescent magenta latex has a weight ratio of solvent red 49 to solvent yellow 98 in a range of 3:1 to 10: 1.

In another aspect, a fluorescent magenta toner is provided. In embodiments, the fluorescent magenta toner comprises fluorescent agent-doped resin particles comprising a resin, solvent red 49 as the red fluorescent agent, and solvent yellow 98 as the yellow fluorescent agent, wherein the fluorescent magenta latex has a weight ratio of solvent red 49 to solvent yellow 98 in the range of 3:1 to 10: 1.

In another aspect, a method of making a fluorescent magenta toner is provided. In embodiments, such methods include forming one or more fluorescent latexes comprising solvent red 49 as a red fluorescent agent, solvent yellow 98 as a yellow fluorescent agent, a first type of amorphous resin, and a second type of amorphous resin, wherein the solvent red 49 and the solvent yellow 98 are present in a weight ratio in a range from 3:1 to 10: 1; forming a mixture comprising: the one or more fluorescent latexes; one or more emulsions comprising a crystalline resin, the first type of amorphous resin, the second type of amorphous resin; and optionally, a wax dispersion; aggregating the mixture to form particles of a predetermined size; forming a shell over the predetermined size particles to form core-shell particles; and coalescing the core-shell particles to form a fluorescent magenta toner.

Drawings

Exemplary embodiments of the present disclosure will be described below with reference to the accompanying drawings.

Fig. 1 shows a reflectance spectrum of a fluorescent magenta toner according to an exemplary embodiment. Toner Mass Area (TMA) was 0.5mg/cm²。

Detailed Description

The present disclosure provides fluorescent magenta latexes and compositions, such as toners and inkjet printing compositions, formed from the fluorescent magenta latexes. Related methods are also provided.

The fluorescent magenta latex of the present invention comprises resin particles having a fluorescent agent incorporated therein, the resin particles being resin particles having a red fluorescent agent and a yellow fluorescent agent incorporated therein. Although some fluorescent latexes have been developed for use in toners, the brightness of such latexes and toners has been limited. The present disclosure is based, at least in part, on the use of a particular pair of fluorescers, solvent red 49 as the red fluorescer, and solvent yellow 98 as the yellow fluorescer. It has been found that this pair is particularly advantageous as the pair is capable of undergoing Forster Resonance Energy Transfer (FRET). Thus, the pair may be referred to as a FRET pair. In order to form a FRET pair, the emission spectrum of the yellow fluorescent agent must overlap sufficiently with the absorption spectrum of the red fluorescent agent. Upon illumination with light to excite the yellow phosphor, the excited yellow phosphor transfers energy to the red phosphor via non-radiative energy transfer to induce fluorescence from the red phosphor. The greater the overlap between the normalized emission spectrum of the yellow fluorescent agent and the normalized absorption spectrum of the red fluorescent agent, the greater the FRET efficiency and the greater the overall fluorescence emission from the fluorescent latex and the composition formed from the fluorescent latex. For solvent yellow 98 and solvent red 49, the degree of overlap is very large, approximately > 90%.

In embodiments, the fluorescent magenta latex of the present invention further comprises a fluorescent whitening agent. The optical brightener may also be selected such that it forms another FRET pair with the yellow fluorescent agent, the red fluorescent agent, or both. Furthermore, the fluorescent whitening agent may be selected to provide a desired degree of overlap of the absorption spectra with its partner, for example greater than 5%, greater than 15%, greater than 20%, greater than 30%, or in the range of 30% to 100%.

In embodiments, the fluorescent whitening agent has an absorption spectrum spanning the range of 300nm to 400nm and an emission spectrum spanning the range of 380nm to 650 nm. This includes optical brighteners having an absorption spectrum spanning the range of 300nm to 380 nm. This includes optical brighteners having emission spectra spanning the range of 400nm to 550 nm. It is also desirable that the fluorescent whitening agent does not absorb light in the range of 380nm to 700 nm. The phrase "does not absorb light" encompasses zero absorption, but also small amounts of absorption, provided that the optical brightener appears colorless to the human eye.

FRET efficiency is also related to the separation distance (d) between the donor fluorescent agent and the acceptor fluorescent agent molecules (efficiency. di.. di^-6). Thus, to actually achieve FRET in the fluorescent magenta latex of the present invention, the red and yellow fluorescent agents and the fluorescent whitening agent, if present, are sufficiently close together (i.e., present in sufficiently high concentrations, although not so high as to cause fluorescence quenching) and homogeneously distributed in the resin particles. The method of forming the fluorescent magenta latex as described further below achieves such appropriate concentrations and homogeneous distribution. Confirmation of FRET may be performed as described further below.

Exemplary optical brighteners include the following: fluorescent brightener 184, optical brightener 1 (fluorescent brightener 393), optical brightener 2, optical brightener 3, optical brightener C, optical brightener OB, optical brightener R, optical brightener Hostalux KSN, optical brightener Hostalux KCB, optical brightener Telalux KSB, fluorescent brightener 127, CBS-127, optical brightener PF, optical brightener UVT1, optical brightener ST, optical brightener OEF, optical brightener RT, Tinopal CBS-X, DMS/CBS-155, 378, 367, 368, 185, 199:1, 199:2, optical brightener ER-IV, optical brightener ER-V, optical brightener 4BK, optical brightener ER-I/ER-I L, optical brightener ER-II/ER-II L, optical brightener EBF/EBF-L, PF/DT, BA, CXT, R4, MST-L, BAC, SWN/AW-L, WGS, NFW, PC, BBU/BBU-L, VBL/VBL-L. In embodiments, the optical brightener is optical brightener 184. Combinations of different types of fluorescent whitening agents may be used.

The relative amounts of red and yellow phosphor were selected to achieve a color channel a of about 76 and a color channel b of about-6. (color channels are described further below.) this relative amount corresponds to a red color in the range of 3:1 to 10:1, 4:1 to 9:1, or 5:1 to 7: 1: weight ratio of yellow. The relative amount of fluorescent whitening agent, if present, may vary compared to the total amount of red and yellow fluorescent agent. In embodiments, (optical brighteners): the weight ratio of (red and yellow phosphor) is in the range of 1:200 to 1:0.01, 1:50 to 1:0.05, or 1:10 to 1: 0.5. The total amount of fluorescent agent (red, yellow, and whitening agent, if present) in the fluorescent magenta latex can be 0.1 wt% to 10 wt% based on the weight of the fluorescent magenta latex. This includes a total amount of 0.1 to 8, 0.2 to 6, 0.5 to 5, and 1 to 2 weight percent. These ranges can be used to achieve appropriate concentrations to ensure FRET while also preventing fluorescence quenching.

Resin composition

The resin particles of the fluorescent magenta latex of the present invention provide a polymeric matrix to hold the red and yellow fluorescent agents and, if present, the fluorescent whitening agent. The resin particles may comprise more than one different type of resin. The resin may be an amorphous resin, a crystalline resin, a mixture of amorphous resins, or a mixture of crystalline and amorphous resins. The resin may be a polyester resin, including an amorphous polyester resin, a crystalline polyester resin, a mixture of amorphous polyester resins, or a mixture of crystalline polyester resins and amorphous polyester resins. Notably, this section also describes resins that can be included in compositions formed from the fluorescent magenta latexes (e.g., toners) of the present invention.

Crystalline resins

The crystalline resin may be a crystalline polyester resin formed by reacting a diol with a diacid in the presence of an optional catalyst. For forming crystalline polyesters, suitable organic diols include aliphatic diols having from about 2 to about 36 carbon atoms, such as 1, 2-ethanediol, 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 2-dimethylpropane-1, 3-diol, 1, 6-hexanediol, 1, 7-heptanediol, 1, 8-octanediol, 1, 9-nonanediol, 1, 10-decanediol, 1, 12-dodecanediol, combinations thereof, and the like, including structural isomers thereof. The aliphatic diol may be selected, for example, in an amount of about 40 to about 60 mole percent of the resin, about 42 to about 55 mole percent of the resin, or about 45 to about 53 mole percent of the resin, and the second diol may be selected in an amount of about 0 to about 10 mole percent of the resin, or about 1 to about 4 mole percent of the resin.

Examples of organic diacids or diesters (including vinyl diacids or vinyl diesters) selected for the preparation of the crystalline resins include oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, fumaric acid, dimethyl fumarate, dimethyl itaconate, cis-1, 4-diacetoxy-2-butene, diethyl fumarate, diethyl maleate, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2, 6-dicarboxylic acid, naphthalene-2, 7-dicarboxylic acid, cyclohexane dicarboxylic acid, malonic acid, and mesaconic acid, their diesters or anhydrides. The organic diacid can be selected, for example, in an amount from about 40 to about 60 mole percent of the resin, from about 42 to about 52 mole percent of the resin, or from about 45 to about 50 mole percent of the resin, and the second diacid can be selected in an amount from about 0 to about 10 mole percent of the resin.

Polycondensation catalysts useful for forming crystalline (as well as amorphous) polyesters include tetraalkyl titanates, dialkyltin oxides such as dibutyltin oxide, tetraalkyltin such as dibutyltin dilaurate, and dialkyltin oxide hydroxides such as butyltin oxide hydroxide, aluminum alkoxides, alkyl zinc, dialkyl zinc, zinc oxide, stannous oxide, or combinations thereof. Such catalysts may be used, for example, in amounts of about 0.01 mole% to about 5 mole%, based on the starting diacid or diester used to form the polyester resin.

Examples of crystalline resins include polyesters, polyamides, polyimides, polyolefins, polyethylene, polybutylene, polyisobutyrate, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, polypropylene, mixtures thereof, and the like. Specific crystalline resins may be polyester-based such as poly (ethylene adipate), poly (propylene adipate), poly (butylene adipate), poly (pentylene adipate), poly (hexylene adipate), poly (octylene adipate), poly (ethylene succinate), poly (propylene succinate), poly (butylene succinate), poly (pentylene succinate), poly (hexylene succinate), poly (octylene succinate), poly (ethylene sebacate), poly (propylene sebacate), poly (butylene sebacate), poly (pentylene sebacate), poly (hexylene sebacate), poly (octylene sebacate), poly (decylate), poly (ethylene decanoate), poly (ethylene dodecanoate), Poly (nonanediol sebacate), poly (nonanediol decanoate), copoly (ethylene fumarate) -copoly (ethylene sebacate), copoly (ethylene fumarate) -copoly (ethylene decanoate), copoly (ethylene fumarate) -copoly (ethylene dodecanoate), copoly (2, 2-dimethylpropane-1, 3-diol-decanoate) -copoly (nonanediol decanoate), poly (octanediol adipate), and mixtures thereof. Examples of polyamides include poly (ethylene glycol-adipamide), poly (propylene glycol-adipamide), poly (butylene glycol-adipamide), poly (pentylene glycol-adipamide), poly (hexylene glycol-adipamide), poly (octylene glycol-adipamide), poly (ethylene glycol-succinimide), poly (propylene glycol-sebacamide), and mixtures thereof. Examples of polyimides include poly (ethylene glycol-adipimide), poly (propylene glycol-adipimide), poly (butylene glycol-adipimide), poly (pentylene glycol-adipimide), poly (hexylene glycol-adipimide), poly (octylene glycol-adipimide), poly (ethylene glycol-succinimide), poly (propylene glycol-succinimide), poly (butylene glycol-succinimide), and mixtures thereof.

In embodiments, the crystalline polyester resin has the following formula (I)

Wherein each of a and b may range from 1 to 12, 2 to 12, or 4 to 12, and further wherein p may range from 10 to 100, 20 to 80, or 30 to 60. In embodiments, the crystalline polyester resin is poly (1, 6-hexanediol-1, 12-dodecanoate), which may be produced by the reaction of dodecanedioic acid with 1, 6-hexanediol.

As described above, the crystalline polyester resins disclosed herein can be prepared by a polycondensation process by reacting a suitable organic diol with a suitable organic diacid in the presence of a polycondensation catalyst. However, in some cases where the organic diol has a boiling point of about 180 ℃ to about 230 ℃, a stoichiometric equimolar ratio of the organic diol and the organic diacid can be utilized, and excess diol (such as about 0.2 to 1 molar equivalent of ethylene glycol or propylene glycol) can be utilized and removed by distillation during the polycondensation process. The amount of catalyst used may vary and may be selected in an amount such as from about 0.01 mole% to about 1 mole% or from about 0.1 mole% to about 0.75 mole% of the crystalline polyester resin.

The crystalline resin may have various melting points, for example, from about 30 ℃ to about 120 ℃, from about 50 ℃ to about 90 ℃, or from about 60 ℃ to about 80 ℃. The crystalline resin may have a number average molecular weight (M) of, for example, about 1,000 to about 50,000, about 2,000 to about 25,000, or about 5,000 to about 20,000 as measured by Gel Permeation Chromatography (GPC)_n) And a weight average molecular weight (M) as determined by GPC, for example, from about 2,000 to about 100,000, from about 3,000 to about 80,000, or from about 10,000 to about 30,000_w). Molecular weight distribution (M) of the crystalline resin_w/M_n) Can be, for example, from about 2 to about 6, from about 3 to about 5, or from about 2 to about 4.

Amorphous resin

The resin may be an amorphous polyester resin formed by reacting a diol with a diacid in the presence of an optional catalyst. Examples of diacids or diesters include vinyl diacids or vinyl diesters used to prepare amorphous polyesters, including dicarboxylic acids or diesters such as terephthalic acid, phthalic acid, isophthalic acid, fumaric acid, trimellitic acid, dimethyl fumarate, dimethyl itaconate, cis-1, 4-diacetoxy-2-butene, diethyl fumarate, diethyl maleate, maleic acid, succinic acid, itaconic acid, succinic anhydride, dodecylsuccinic acid, dodecylsuccinic anhydride, glutaric acid, glutaric anhydride, adipic acid, pimelic acid, suberic acid, azelaic acid, dodecanedioic acid, dimethyl terephthalate, diethyl terephthalate, dimethyl isophthalate, diethyl isophthalate, dimethyl phthalate, phthalic anhydride, diethyl phthalate, dimethyl succinate, dimethyl suberate, phthalic anhydride, diethyl phthalate, dimethyl succinate, dimethyl suberate, maleic anhydride, or maleic anhydride, or, Dimethyl fumarate, dimethyl maleate, dimethyl glutarate, dimethyl adipate, dimethyl dodecylsuccinate, and combinations thereof. The organic diacid or diester can be present, for example, in an amount of from about 40 mole% to about 60 mole% of the resin, from about 42 mole% to about 52 mole% of the resin, or from about 45 mole% to about 50 mole% of the resin.

Examples of diols that can be used to form the amorphous polyester include 1, 2-propanediol, 1, 3-propanediol, 1, 2-butanediol, 1, 3-butanediol, 1, 4-butanediol, pentanediol, hexanediol, 2-dimethylpropanediol, 2, 3-trimethylhexanediol, heptanediol, dodecanediol, bis (hydroxyethyl) -bisphenol a, bis (2-hydroxypropyl) -bisphenol a, 1, 4-cyclohexanedimethanol, 1, 3-cyclohexanedimethanol, xylene dimethanol, cyclohexanediol, diethylene glycol, bis (2-hydroxyethyl) oxide, dipropylene glycol, dibutylene, and combinations thereof. The amount of organic diol selected may vary, for example, the organic diol may be present in an amount from about 40 to about 60 mole percent of the resin, from about 42 to about 55 mole percent of the resin, or from about 45 to about 53 mole percent of the resin.

Examples of suitable amorphous resins include polyesters, polyamides, polyimides, polyolefins, polyethylenes, polybutylenes, polyisobutyrates, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, polypropylenes, and the like, and mixtures thereof.

Unsaturated amorphous polyester resins may be used as the resin. Examples of such resins include those disclosed in U.S. Pat. No. 6,063,827, the disclosure of which is hereby incorporated by reference in its entirety. Exemplary unsaturated amorphous polyester resins include, but are not limited to, poly (propoxylated bisphenol co-fumarate), poly (ethoxylated bisphenol co-fumarate), poly (butoxylated bisphenol co-fumarate), poly (co-propoxylated bisphenol co-ethoxylated bisphenol co-fumarate), poly (1, 2-propanediol fumarate), poly (propoxylated bisphenol co-maleate), poly (ethoxylated bisphenol co-maleate), poly (butoxylated bisphenol co-maleate), poly (co-propoxylated bisphenol co-ethoxylated bisphenol co-maleate), poly (1, 2-propanediol maleate), poly (propoxylated bisphenol co-itaconate), poly (ethoxylated bisphenol co-itaconate), poly (butoxylated bisphenol co-itaconate), poly (co-propoxylated bisphenol co-ethoxylated bisphenol co-itaconate), Poly (1, 2-propylene glycol itaconate), and combinations thereof.

Suitable polyester resins may be amorphous polyesters such as poly (propoxylated bisphenol a co-fumarate) resins. Examples of such resins and methods of making them include those disclosed in U.S. Pat. No. 6,063,827, the disclosure of which is hereby incorporated by reference in its entirety.

Suitable polyester resins include amorphous acidic polyester resins. The amorphous acidic polyester resin may be based on any combination of propoxylated bisphenol a, ethoxylated bisphenol a, terephthalic acid, fumaric acid, and dodecenyl succinic anhydride, such as poly (propoxylated bisphenol-co-terephthalate-fumarate-dodecenyl succinate). Another amorphous acidic polyester resin that may be used is poly (propoxylated-ethoxylated bisphenol-co-terephthalate-dodecenyl succinate-trimellitic anhydride).

An example of a linear propoxylated bisphenol A fumarate resin that can be used as the resin is available from Resana S/A Industrial quiica, Sao Paulo Brazil under the trade name SPAMII. Other propoxylated bisphenol a fumarate resins that may be used and are commercially available include GTUF and FPESL-2 from Kao Corporation, Japan, and EM181635 from Reichhold, Research Triangle Park, n.c. and the like.

The amorphous resin or combination of amorphous resins may have a glass transition temperature of about 30 ℃ to about 80 ℃, about 35 ℃ to about 70 ℃, or about 40 ℃ to about 65 ℃. The glass transition temperature can be measured using Differential Scanning Calorimetry (DSC)Amount of the compound (A). The amorphous resin may have, for example, an M of from about 1,000 to about 50,000, from about 2,000 to about 25,000, or from about 1,000 to about 10,000 as measured by GPC_nAnd an M, for example, from about 2,000 to about 100,000, from about 5,000 to about 90,000, from about 10,000 to about 30,000, or from about 70,000 to about 100,000 as determined by GPC_w。

The resin in the toner of the present invention may have acid groups that may be present at the end of the resin. Acidic groups that may be present include carboxylic acid groups and the like. The number of carboxylic acid groups can be controlled by adjusting the materials and reaction conditions used to form the resin. In embodiments, the resin is a polyester resin having an acid value of from about 2 to about 200, from about 5 to about 50, or from about 5 to about 15mgKOH/g of resin. The acid-containing resin may be dissolved in a tetrahydrofuran solution. The acid number can be detected by titration with a KOH/methanol solution containing phenolphthalein as an indicator. The acid number can then be calculated based on the number of equivalents of KOH/methanol required to neutralize all acid groups on the resin identified as the titration end point.

The fluorescent magenta latex of the present invention can comprise a single type of resin, such as a single type of amorphous polyester resin, or multiple types of resins, such as two different types of amorphous polyester resins. In such embodiments, one of the amorphous polyester resins has a larger M than the other_nOr M_w. In embodiments where two different types of amorphous polyester resins are used, the weight ratio of the two types may be 2:3 to 3: 2. This includes a 1:1 weight ratio. Alternatively, two separate fluorescent magenta latexes can be used, each comprising a different type of amorphous polyester resin. However, the one or more fluorescent magenta latexes together provide two different types of amorphous polyester resins within this weight ratio range. These weight ratios can be used to ensure a homogeneous distribution of the fluorescent agent once incorporated into the resin particles. This also prevents fluorescence quenching while facilitating FRET.

The total amount of resin may be present in the fluorescent red latex in an amount of, for example, 1 to 60 weight percent based on the weight of the fluorescent latex. This includes a total amount of resin in the range of 5 to 50 weight percent and 10 to 40 weight percent.

As described above, the resin incorporating the fluorescent agent is in the form of particles. The particles may have an average size in the range of 20nm to 1000nm as measured by dynamic light scattering.

Other Components

The fluorescent magenta latexes of the invention also typically comprise one or more solvents, although they can also be utilized in dry form. Water is typically used as the solvent, but may include one or more organic solvents. Other components may be included, such as one or more types of antifoam agents, one or more types of surfactants, one or more types of biocides. Surfactants include sodium lauryl sulfate, Calfax/Dowfax, sodium dioctyl sulfosuccinate, sodium dodecyl benzene sulfonate, and the like. Biocides include Proxel GXL, Kathon biocides, Bioban preservatives, Rocima 586 microblades, Ucarcide antimicrobials, Dosidide antimicrobials, and the like.

Preparation of fluorescent magenta latex

Resin particles incorporating a fluorescent agent and a fluorescent magenta latex containing the particles can be prepared as follows. The mixture may be formed by combining the desired fluorescing agent, the desired resin, and the solvent. The solvent may be a solvent system comprising one or more organic solvents (acetone, tetrahydrofuran, ethyl acetate, methyl ethyl ketone, methylene chloride, methanol, ethanol, n-propanol, isopropanol, butanol, etc.) and water. Other additives may be included in the mixture, such as one or more types of surfactants (see "other components" above) and one or more types of bases (sodium hydroxide, potassium hydroxide, ammonia, triethylamine, sodium bicarbonate, etc.)

As noted above, the desired fluorescers may include both red fluorescers, yellow fluorescers, and one or more types of optical brighteners. The desired resin may include more than one type of resin. The FRET pair is expected to be formed in the same fluorescent latex in order to facilitate FRET. However, as also described above, separate fluorescent latexes may be prepared and used, such as one fluorescent latex comprising a yellow fluorescent agent and another fluorescent latex comprising a red fluorescent agent.

The resulting fluorescer/resin/solvent mixture is heated to a certain temperature (e.g. 30 ℃ to 80 ℃, 40 ℃ to 75 ℃, 45 ℃ to 70 ℃) and held for a certain time (e.g. 20 minutes to 5 hours, 30 minutes to 2 hours, 1 hour) while mixing to homogenize the mixture. Additional base may be added to neutralize the resin while mixing. Mixing is performed to ensure homogenization and to provide phosphor-doped resin particles of a desired size. (mixing and homogenization are described further below with respect to the toner.) an amount of surfactant and/or biocide may be added. Finally, the organic solvent may be removed by distillation. Water may be added during the process to maintain the desired solids content. The resulting fluorescent magenta latex can be used to form any kind of composition in which fluorescence is desired. Exemplary compositions include toners and inkjet printing compositions, thereby making such compositions fluorescent. These exemplary compositions are further described below.

The fluorescence of the fluorescent magenta latex and the presence of FRET present in the fluorescent magenta latex can be confirmed and quantified using a densitometer (such as Hunter, X-Rite, etc.) or a fluorescence spectrometer operating according to the manufacturer's instructions. These systems can be used to determine the brightness L, color channels a and b, and reflectance of the fluorescent magenta latex. With respect to the luminance L, the CIELAB color space (also referred to as CIE L a b, or sometimes simply "Lab" color space) is a color space defined by the international commission on illumination (CIE). It expresses color as three values: luminance L from black (0) to white (100), a from green (-) to red (+), and b from blue (-) to yellow (+).

Since three parameters are measured, the space itself is a three-dimensional real space, which allows an infinite number of possible colors. In practice, this space is typically mapped onto a three-dimensional integer space for numerical representation, so the L, a, and b values are typically absolute, with predefined ranges. The luminance value L indicates the darkest black color at L ═ 0 and the brightest white color at L ═ 100. Color channels a and b represent true neutral gray values when a is 0 and b is 0. The a-axis represents the green-red component, with green in the negative direction and red in the positive direction. b-axis represents the blue-yellow component, with blue in the negative direction and yellow in the positive direction. Scaling and limiting of the a-axis and b-axis will depend on the specific implementation, but will typically be in the range of ± 100 or-128 to +127 (signed 8-bit integer).

As noted above, the fluorescent magenta latex of the present invention is characterized by a color channel a of about 76 and a color channel b of about-6. A fluorescent magenta latex having at least one pair of FRET of solvent red 49 and solvent yellow 98 and exhibiting FRET (due to appropriate concentration and homogeneous distribution) is characterized by having significantly greater brightness L x and reflectance values than a comparative fluorescent latex having different combinations of red and yellow fluorescent agents (e.g., solvent red 49 and solvent yellow 160: 1). By incorporating optical brighteners, the brightness L and the reflectivity are even greater. As shown in the examples below, the fluorescent magenta latex containing solvent Red 49, solvent yellow 98 and optical brightener was at 0.5mg/cm when irradiated with Ultraviolet (UV) light²Exhibits a peak reflectance (i.e., reflectance value at the peak) at 610nm that is more than 20 units higher than a comparative fluorescent magenta latex comprising solvent red 49, solvent yellow 160:1, and the same fluorescent brightener.

Toner and image forming apparatus

To form the toner of the present invention, any of the resins described above may be provided as an emulsion, for example, by using a solvent-based phase inversion emulsification process. The emulsion may then be used as a starting material to form a toner, for example, by using an emulsion aggregation and coalescence (EA) process. However, other methods may be used to prepare the toner. As described above, any of the above-described fluorescent magenta latexes can be used in a toner preparation process to form a fluorescent magenta toner.

The toner may also contain a wax, which may be incorporated into the toner as a separate dispersion in water. However, the toner generally does not include any pigment or any other colorant other than the above-described fluorescent agent.

Wax

Optionally, a wax may be included in the toner of the present invention. A single type of wax or a mixture of two or more different waxes may be used. For example, a single wax may be added to improve specific toner properties, such as toner particle shape, presence and amount of wax on the toner particle surface, charging and/or fusing characteristics, gloss, release, offset properties, and the like. Alternatively, a combination of waxes may be added to provide various properties to the toner composition.

When included, the wax may be present in, for example, the following amounts: from about 1 wt% to about 25 wt% by weight of the toner, or from about 5 wt% to about 20 wt% by weight of the toner particles.

When a wax is used, the wax may include any of various waxes conventionally used in emulsion aggregation toners. Waxes that may be selected include waxes having an average molecular weight of, for example, about 500 to about 20,000, or about 1,000 to about 10,000. Waxes that may be used include, for example, polyolefins such as polyethylene (including linear polyethylene waxes and branched polyethylene waxes), polypropylene (including linear polypropylene waxes and branched polypropylene waxes), polymethylene waxes, polyethylene/amides, polyethylene tetrafluoroethylene/amides, and polybutylene waxes, such as are commercially available from Allied Chemical and Petrolite Corporation, such as POLYWAX, which is commercially available from Baker Petrolite^TMPolyethylene wax, wax emulsions available from Michaelman, Inc. and Daniels Products Company, EPOLENE N-15, commercially available from Eastman Chemical Products, Inc^TMAnd VISCOL 550-P available from Sanyo Kasei K.K^TM(low weight average molecular weight polypropylene); vegetable-based waxes such as carnauba wax, rice wax, candelilla wax, sumac wax, and jojoba oil; animal-based waxes, such as beeswax; mineral-based and petroleum-based waxes, such as montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax (such as that derived from crude oil distillation), silicone wax, mercapto wax, polyester wax, urethane wax; modified polyolefin waxes (such asA carboxylic acid-terminated polyethylene wax or a carboxylic acid-terminated polypropylene wax); a Fischer-Tropsch wax; ester waxes obtained from higher fatty acids and higher alcohols, such as stearyl stearate and behenyl behenate; ester waxes obtained from higher fatty acids and monovalent or polyvalent lower alcohols, such as butyl stearate, propyl oleate, glycerol monostearate, glycerol distearate, and pentaerythritol tetrabehenate; ester waxes obtained from higher fatty acids and polyvalent alcohol polymers, such as diethylene glycol monostearate, dipropylene glycol distearate, diglycerin distearate, and triglycerol tetrastearate; sorbitan higher fatty acid ester waxes such as sorbitan monostearate, and cholesterol higher fatty acid ester waxes such as cholesteryl stearate. Examples of functionalized waxes that may be used include, for example, amines, amides (e.g., AQUA SUPERSLIP 6550 available from Micro Powder Inc^TM、SUPERSLIP 6530^TM) Fluorinated waxes (e.g., POLYFLUO190 available from Micro Powder Inc.)^TM、POLYFLUO 200^TM、POLYSILK 19^TM、POLYSILK 14^TM) Mixed fluorinated amide waxes (such as aliphatic polar amide functionalized waxes); an aliphatic wax consisting of: esters of hydroxylated unsaturated fatty acids (e.g. MICROSPIRSION 19)^TMAlso available from Micro Powder Inc.), imides, esters, quaternary amines, carboxylic or acrylic polymer emulsions (e.g., JONCRYL 74)^TM、89^TM、130^TM、537^TMAnd 538 to^TMBoth available from SC Johnson Wax), as well as chlorinated polypropylene and polyethylene (available from Allied Chemical and Petrolite Corporation) and SC Johnson Wax. Mixtures and combinations of the foregoing waxes may also be used in embodiments. The wax may be included as, for example, a fuser roll release agent. In embodiments, the wax may be crystalline or non-crystalline.

In embodiments, the toner is prepared by an EA process, such as by aggregating a mixture of: an emulsion comprising a resin; red fluorescer, yellow fluorescer and fluorescent whitening agent (if present, provided as one or more fluorescent latexes, but preferably as one to ensure FRET); and optionally, a wax (provided as a separate dispersion); and subsequently coalescing the mixture. The resin-containing emulsion may contain one or more resins, or different resins may be provided as different emulsions. Emulsions comprising resins typically do not contain a fluorescent agent and therefore do not contain a fluorescent agent. To ensure a homogeneous distribution of FRET pairs and achieve FRET without fluorescence quenching in the final toner, during EA, the red-yellow FRET pairs are provided as one or more fluorescent latexes (and preferably one) separate from the other components of the mixture, and the fluorescent agent itself is not simply added to the mixture.

Next, the mixture may be homogenized, which may be achieved by mixing at about 600 revolutions per minute to about 6,000 revolutions per minute. Homogenization may be achieved by any suitable means, including for example an IKA ULTRA TURRAX T50 probe homogenizer. An aggregating agent may be added to the mixture. Any suitable aggregating agent may be used. Suitable aggregating agents include, for example, aqueous solutions of divalent cationic or multivalent cationic materials. The aggregating agent may be, for example, an inorganic cationic aggregating agent, such as a polyaluminium halide, such as polyaluminium chloride (PAC), or the corresponding bromide, fluoride or iodide; polyaluminiums silicates such as Polyaluminumsulfosilicate (PASS); or a water-soluble metal salt including aluminum chloride, aluminum nitrite, aluminum sulfate, potassium aluminum sulfate, calcium acetate, calcium chloride, calcium nitrite, calcium oxide, calcium sulfate, magnesium acetate, magnesium nitrate, magnesium sulfate, zinc acetate, zinc nitrate, zinc sulfate, zinc chloride, zinc bromide, magnesium bromide, copper chloride, and copper sulfate; or a combination thereof. Can be below the glass transition temperature (T) of the resin_g) The aggregating agent is added to the mixture at the temperature of (a). The aggregating agent may be added to the mixture under homogenization.

The aggregating agent may be added to the mixture, for example, in the following amounts: from about 0 wt% to about 10 wt% by weight of the total amount of resin, from about 0.2 wt% to about 8 wt% by weight of the total amount of resin, or from about 0.5 wt% to about 5 wt% by weight of the total amount of resin.

The particles of the mixture may be agglomerated until a predetermined desired particle size is obtained. The predetermined desired particle size refers to the desired particle size to be obtained as determined prior to formation and the particle size is monitored during the growth process until the particle size is reached. Samples can be taken during the growth process and the volume average particle size analyzed, for example, with a coulter counter. Thus, aggregation may be carried out by maintaining an elevated temperature, or slowly raising the temperature, for example, to in embodiments from about 30 ℃ to about 100 ℃, in embodiments from about 30 ℃ to about 80 ℃, or in embodiments from about 30 ℃ to about 50 ℃. While stirring, the temperature may be maintained for a period of time of from about 0.5 hours to about 6 hours, or in embodiments from about 1 hour to about 5 hours, to provide aggregated particles. Once the predetermined desired particle size is reached, a shell may be added (although a shell is not desired). The volume average particle size of the particles prior to application of the shell may be, for example, from about 3 μm to about 10 μm, in embodiments from about 4 μm to about 9 μm, or from about 6 μm to about 8 μm.

Shell resin

After aggregation, but before coalescence, a resin coating may be applied to the aggregated particles to form a shell thereon. Any of the above resins may be used in the shell. In embodiments, an amorphous polyester resin is used in the shell. In embodiments, two (different types of) amorphous polyester resins are utilized in the shell. In embodiments, a crystalline polyester resin and two different types of amorphous polyester resins are utilized in the core, and two different types of amorphous polyester resins are utilized in the shell. The shell resin typically does not contain a phosphor, and thus does not contain a phosphor.

The shell may be applied to the aggregated particles by using a shell resin in the form of an emulsion as described above. Such emulsions may be mixed with the aggregated particles under conditions sufficient to form a coating on the aggregated particles. For example, forming a shell over the aggregated particles can occur upon heating to a temperature of about 30 ℃ to about 80 ℃, or about 35 ℃ to about 70 ℃. Shell formation may occur for a period of time from about 5 minutes to about 10 hours, or from about 10 minutes to about 5 hours.

Once the desired size of toner particles is achieved, the pH of the mixture may be adjusted to a value of from about 3 to about 10, or in embodiments from about 5 to about 9, using a pH control agent (e.g., a base). The adjustment of pH can be used to freeze (i.e., stop) toner growth. The base used to inhibit toner growth may include any suitable base, such as, for example, an alkali metal hydroxide, such as, for example, sodium hydroxide, potassium hydroxide, ammonium hydroxide, combinations thereof, and the like. In embodiments, a chelating agent such as ethylenediaminetetraacetic acid (EDTA) may be added to help adjust the pH to the desired value described above. Other chelating agents may be used.

In embodiments, the size of the core-shell toner particles (prior to coalescence) may be from about 3 μm to about 10 μm, from about 4 μm to about 10 μm, or from about 6 μm to about 9 μm.

Coalescence

After aggregation to the desired particle size and application of the shell (if any), the particles may be agglomerated to the desired final shape, the agglomeration being achieved by, for example: the mixture is heated to a temperature of about 45 ℃ to about 150 ℃, about 55 ℃ to about 99 ℃, or about 60 ℃ to about 90 ℃, which may be equal to or higher than the glass transition temperature of the resin used to form the toner particles. Heating may continue or the pH of the mixture may be adjusted (e.g., lowered) over a period of time to achieve the desired circularity. The time period may be from about 1 hour to about 5 hours, or from about 2 hours to about 4 hours. Various buffers can be used during coalescence. The total time period for coalescence may be from about 1 to about 9 hours, from about 1 to about 8 hours, or from about 1 to about 5 hours. Agitation may be utilized during coalescence, for example from about 20rpm to about 1000rpm or from about 30rpm to about 800 rpm.

After aggregation and/or coalescence, the mixture may be cooled to room temperature. Cooling may be rapid or slow as desired. A suitable cooling process may include introducing cold water into the jacket around the reactor. After cooling, the toner particles may be screened with a sieve of a desired size, filtered, washed with water, and then dried. Drying may be achieved by any suitable drying method, including for example freeze drying.

In the toner, the total amount of fluorescent agents (red, yellow and fluorescent whitening agents, if present) may be present in an amount of, for example, 0.1 to 10 wt%, based on the weight of the toner. This includes a total amount of 0.1 to 8 wt% by weight of the toner, 0.2 to 6 wt% by weight of the toner, 0.5 to 5 wt% by weight of the toner, and 1 to 2 wt% by weight of the toner. These ranges can be used to ensure appropriate concentrations for achieving FRET while also preventing fluorescence quenching. The relative amounts of the red and yellow fluorescent agents and the fluorescent whitening agents to the total amount of red and yellow fluorescent agents may be as described above for the fluorescent magenta latex.

In the toner, the crystalline resin may be present in an amount of, for example, from about 1 wt% to about 85 wt% by weight of the toner, from about 5 wt% to about 50 wt% by weight of the toner, or from about 10 wt% to about 35 wt% by weight of the toner. The amorphous resin or combination of amorphous resins may be present, for example, in an amount of from about 5 wt% to about 95 wt% by weight of the toner, from about 30 wt% to about 90 wt% by weight of the toner, or from about 35 wt% to about 85 wt% by weight of the toner. In embodiments, crystalline and amorphous resins are used, and the weight ratio of the resins is from about 80 to about 60 weight percent amorphous resin and from about 20 to about 40 weight percent crystalline resin. In such embodiments, the amorphous resin may be a combination of different types of amorphous resins, such as a combination of two different types of amorphous resins. In embodiments, one of these amorphous resins has a larger M than the other_nOr M_w。

Other additives

In embodiments, the toner may also contain other optional additives. For example, the toner may contain a positive charge control agent or a negative charge control agent. Surface additives may also be used. Examples of surface additives include metal oxides such as titanium oxide, silicon oxide, aluminum oxide, cerium oxide, tin oxide, mixtures thereof, and the like; colloidal silica and amorphous silica, such asMetal salts and metal salts of fatty acids (such as zinc stearate, calcium stearate and magnesium stearate), itMixtures thereof, and the like; long chain alcohols, such as UNILIN 700; and mixtures thereof. Each of these surface additives may be present in an amount of about 0.1 wt% to about 5 wt% by weight of the toner or about 0.25 wt% to about 3 wt% by weight of the toner.

Developer and carrier

The toner may be formulated into a developer composition. Developer compositions can be prepared by mixing the toner with known carrier particles, including coated carriers such as steel, ferrites, and the like. Such carriers include those disclosed in U.S. Pat. nos. 4,937,166 and 4,935,326, the entire disclosure of each of which is incorporated herein by reference. The toner may be present in the carrier in an amount of from about 1% to about 15%, from about 2% to about 8%, or from about 4% to about 6% by weight. The carrier particles may also include a core having a polymer coating thereon, such as Polymethylmethacrylate (PMMA), in which a conductive component, such as conductive carbon black, is dispersed. The washcoat includes silicone resins such as methyl silsesquioxane, fluoropolymers such as polyvinylidene fluoride, mixtures of resins not immediately adjacent in the triboelectric series such as polyvinylidene fluoride and acrylic resins, thermosetting resins such as acrylic resins, mixtures thereof, and other known components.

Applications of

The toner can be used in a variety of xerographic processes and in a variety of xerographic copiers. Xerographic imaging processes include, for example, preparing an image with a xerographic printer comprising a charging member, an imaging member, a photoconductive member, a developing member, a transfer member and a fixing member. In embodiments, the developing component can include a developer prepared by mixing a carrier with any of the toners described herein. The xerographic printer may be a high speed printer, a black and white high speed printer, a color printer, or the like. Once the image is formed with the toner/developer, the image may be transferred to an image receiving medium, such as paper or the like. The fuser roller member can be used to fuse toner to an image receiving medium by using heat and pressure.

Ink jet printing composition

Another exemplary composition that may be formed from the fluorescent magenta latex of the present invention is an inkjet printing composition. Such compositions are configured to be jettable via an inkjet printing system. Such compositions can include the disclosed fluorescent magenta latex, a solvent (such as water), optionally a co-solvent (such as a water-soluble or water-miscible organic solvent), and optionally an additive, such as a surfactant, a viscosity modifier that adjusts the viscosity of the inkjet printing composition, or a surface leveling agent that adjusts the surface tension of the inkjet printing composition. The desired components may be combined and mixed in the desired amounts. The ink jet printing composition can be used with commercially available ink jet printing systems. Exemplary solvents, co-solvents, additives, exemplary amounts, and exemplary ink jet printing systems include those as described in U.S. patent publication 20190367753, which is hereby incorporated by reference in its entirety. When such inkjet printing compositions are used to form images, the inkjet printing compositions may be deposited on a desired substrate via an inkjet printing system. The solvent or solvents may then be evaporated from the as-deposited ink jet printing composition.

Examples

The following examples are submitted to illustrate various embodiments of the present disclosure. This example is intended to be illustrative only and is not intended to limit the scope of the present disclosure. In addition, parts and percentages are by weight unless otherwise indicated. As used throughout this patent specification, "room temperature" refers to a temperature of 20 ℃ to 25 ℃.

The fluorescent latex was prepared as follows. In a 2L reactor at 40 ℃, a mixture of 120g of the amorphous polyester resin of the first type, 80g of the amorphous polyester resin of the second type, one or more fluorescent agents (see table 1 below) was dissolved in a mixture of acetone, ethyl acetate and aqueous ammonia solution (ratio 145g/48g/40 g). Additional alkali solution was added to each mixture to completely neutralize the polyester resin. After about one hour and complete homogenization, deionized water was added to each mixture. The organic solvent was removed by applying vacuum, and water was added during the process to maintain the desired amount of water (to achieve the desired% solids). Finally, the resulting emulsion was filtered through a 25 μm sieve. The emulsion had an average particle size of about 250nm and a solids content of about 30%. The total fluorescer content in the emulsion was about 1%. Surfactants (Calfax) and biocides (Proxel GXL) were added to stabilize the fluorescent latex and prevent biological growth.

TABLE 1 fluorescent latexes。

Sample (I)	Solvent Red 49(pph)	Solvent yellow 160:1(pph)	Solvent yellow 98(pph)	Fluorescent whitening agent (pph)
					1	--	1.8	--	--
2	--	1	--	0.5
					3	--	--	2.0
4	--	--	2.0	2.0
					5	2.0	--	--	--
6	4.0	--	0.6	--
					7	4.0	--	0.6	2.0
8	4.0	0.2	--	--
					9	1.8	--	--	1.8

Fluorescent toners were prepared using the fluorescent latexes of table 1 and a combination of the fluorescent latexes of table 1. The emulsion aggregation process is used as described herein.

Specifically, for each toner, a mixture is formed by combining: one or more of the fluorescent latexes of table 1; a first emulsion comprising a crystalline polyester resin; a second emulsion comprising a first type of amorphous polyester resin; and a third emulsion comprising a second type of amorphous polyester resin. Next, the mixture is acidified. Next, aluminum sulfate (ALS) solution was slowly added while homogenizing the mixture after adjusting its pH to below 5. The highly viscous mixture was transferred to a 2L reactor and aggregation was initiated by increasing the temperature to about 45 ℃. When the particle size (D50v) reached about 7.0 μm, an emulsion containing two amorphous polyester resins was added to the mixture to form a shell over the particles and the particles continued to grow. The particles were frozen by addition of chelating agent (EDTA) and base (NaOH). The reactor temperature was raised to about 84 ℃ for coalescence. The heating is stopped when the particles reach the desired roundness. The particle slurry was quenched and then the particles were sieved and filtered under vacuum. The filtered particles were washed with deionized water and freeze-dried.

The reflectance spectra of the fluorescent toner printed on the paper were collected using a Gretag X-Rite type instrument. The results for some of the toners are shown in fig. 1. Toner 1 was formed from a mixture containing the fluorescent latex of sample 7. Toner 2 was formed from a mixture comprising the fluorescent latex of sample 4 and the fluorescent latex of sample 5. Toner 3 was formed from a mixture comprising the fluorescent latex of sample 2 and the fluorescent latex of sample 5.

As a result, it was confirmed that magenta fluorescence was emitted from the toner. The results also show that toner 1 exhibited the maximum peak reflectance (i.e., reflectance value at the peak). The toner includes solvent red 49, solvent yellow 98, and a fluorescent whitening agent. The peak reflectance of toner 1 is significantly greater than that of toner 2 in which the same red and yellow fluorescent agents are provided but in two different fluorescent latexes. However, the peak reflectance of toner 2 is still greater than the peak reflectance of toner 3 where the red and yellow fluorescent agents are also provided in two different fluorescent latexes but solvent yellow 160:1 is used instead of solvent yellow 98. It is believed that the additional reflectance of toner 2 compared to toner 3 is due at least in part to the FRET that occurs between solvent yellow 98 and solvent red 49, which is facilitated by the fluorescent latex formation process used above. The additional reflectance of toner 1 compared to toner 2 is believed to be due to the more efficient FRET process that occurs due to the use of a single fluorescent magenta latex. The results show that toner 1 is a fluorescent magenta toner with enhanced brightness.

It will be appreciated that variations of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.