阅读说明：本技术 一种混晶型色酚as有机颜料及其制备方法 (Mixed crystal type naphthol AS organic pigment and preparation method thereof ) 是由 陶明 谢淑雯 王栋鹏 吴贻良 马引民 于 2020-06-16 设计创作，主要内容包括：本发明属于着色剂的制备领域,涉及一种混晶型色酚AS有机颜料及其制备方法。这种混晶型色酚AS有机颜料I是由两个有机颜料分子Ia和Ib组成,Ib分子中R<Sub>1</Sub>,R<Sub>2</Sub>和R<Sub>3</Sub>可以是烷基,烷氧基,硝基,卤素或杂环其中的一种或多种。解决了现有环氧树脂及其预浸料操作时间短和阻燃性差问题。(The invention belongs to the field of preparation of coloring agents, and relates to a mixed crystal type naphthol AS organic pigment and a preparation method thereof. The mixed crystal form naphthol AS organic pigment I consists of two organic pigment molecules Ia and Ib, wherein R in Ib molecule 1 ，R 2 And R 3 May be one or more of alkyl, alkoxy, nitro, halogen or heterocycle. Solves the problems of short operation time and poor flame retardance of the prior epoxy resin and prepreg thereof.)

1. A mixed crystal type naphthol AS organic pigment is characterized in that:

the mixed crystal form naphthol AS organic pigment I consists of two organic pigment molecules Ia and Ib, wherein R in Ib molecule₁，R₂And R₃Can be one or more of alkyl, alkoxy, nitro, halogen or heterocycle, and the structure of IThe formula is as follows:

2. the preparation method of the mixed crystal form naphthol AS organic pigment according to claim 1, which is characterized by comprising the following steps:

the preparation method of I has three methods:

a. hybrid coupling method: diazotizing 3-amino-4-methoxybenzoyl aniline, and then carrying out coupling reaction on the diazotized 3-amino-4-methoxybenzoyl aniline, the coupling component 2 ', 5 ' -dimethoxy-4 ' -chloro-3-hydroxy-2-naphthoyl aniline of Ia and the coupling component naphthol AS and derivatives thereof of Ib in a mixture with a molar ratio of 100:1 to 1:1 in water in the presence of a surfactant with an HLB value of 15-18, and heating, filtering, rinsing, drying and grinding the obtained pigment suspension to obtain I;

b. coating coupling method: diazotizing 3-amino-4-methoxybenzoyl aniline, firstly coupling with a certain amount of coupling component naphthol AS of Ib and derivatives thereof in the presence of a surfactant with an HLB value of 15-18, then coupling with coupling component 2 ', 5 ' -dimethoxy-4 ' -chloro-3-hydroxy-2-naphthoyl aniline of Ia, and heating, filtering, rinsing, drying and grinding the obtained pigment suspension to obtain I;

c. a mixing and grinding method: diazotizing two parts of 3-amino-4-methoxybenzoyl aniline, then respectively mixing the diazotized two parts of 3-amino-4-methoxybenzoyl aniline with a coupling component of 2 ', 5 ' -dimethoxy-4 ' -chloro-3-hydroxy-2-naphthoyl aniline and a coupling component of naphthol AS for synthesizing Ib and derivatives thereof to prepare a suspension or a filter cake of Ia and Ib, then uniformly mixing the suspension or the filter cake according to a molar ratio of 100:1 to 1:1, grinding the mixture to a fineness of less than or equal to 40 mu m by using a colloid grinder, and heating, filtering, rinsing, drying and grinding the mixture to obtain I.

3. The preparation method of the mixed crystal form naphthol AS organic pigment according to claim 2, wherein the method comprises the following steps: the diazotization reaction for preparing the compound I is carried out in a water/inorganic acid medium, and the completeness of the diazotization is monitored by adopting thin-layer chromatography, so that the diazotization reaction is ensured to be complete, and the content of diazotization components in a final product is less than or equal to 100 ppm.

4. The preparation method of the mixed crystal form naphthol AS organic pigment according to claim 2, wherein the method comprises the following steps: the coupling reaction for preparation I is carried out in an acid-out solution of the coupling component. The coupling reaction is completely carried out by adopting the coupling assistant agent, the content of unreacted coupling components in the obtained pigment is low, the condition that the content of 4-chloro-2, 5-dimethoxyaniline in the product exceeds 150ppm due to hydrolysis of the coupling components in the post-process is avoided, and the safety of the product in human contact and food packaging application is ensured.

5. The preparation method of the mixed crystal form naphthol AS organic pigment according to claim 2, wherein the method comprises the following steps: the molar ratio of Ia to Ib in the I can be adjusted according to the needs, so that a rubiginous spectrum from a yellow phase to a blue phase is obtained, and different application requirements can be met.

6. The use of a mixed crystal form of a naphthol AS organic pigment according to claim 2, wherein: the three different preparation methods can obtain products which can meet different requirements of customers on product transparency; the mixing and coupling method can prepare a high-transparency product which is suitable for manufacturing packaging ink; the coating coupling method can prepare a product with moderate transparency, and is suitable for manufacturing digital ink jet; the mixing method can prepare relatively covered products, and is suitable for coloring plastics and special decorative materials.

Technical Field

The invention belongs to the field of preparation of coloring agents, and relates to a mixed crystal type naphthol AS organic pigment and a preparation method thereof.

Background

The naphthol AS series organic pigments are red organic pigments prepared by coupling a diazonium salt of a substituted aromatic amine with 2-hydroxy-N-substituted phenyl-3-naphthamide and are widely used for coloring paints, inks and plastics [ W.Herbst, Industrial organic pigments, Thirdedition, ISBN: 3-527-. One important variety, N- (4-chloro-2, 5-dimethoxyphenyl) -3-hydroxy-4- [ [ 2-methoxy-5- [ (anilino) -carbonyl ] phenyl ] azo ] -2-naphthalimide Ia, organic pigment Red 146, has good solvent resistance, acid and base resistance and retort resistance, and is used for packaging inks and digital inkjet four-color Red. In recent years, with the development of package printing applications and the popularization of digital ink-jet technology applications, the chromatographic requirements of four-color red are widened, and the hue angle of 0.8 degrees (D65,10 degrees) of the original rubine color cannot meet the requirements of different applications; in addition, since the fields of application of packaging inks and digital inkjet inks are related to human contact and food packaging, there is a high demand for the content of harmful substances in the products. The color properties (hue angle, saturation and transparency) of conventional products and the content of harmful components of the products are to be improved.

Disclosure of Invention

The invention mainly solves the defects in the prior art, and provides a mixed crystal type naphthol AS organic pigment and a preparation method thereof, which solve the problems of short operation time and poor flame retardance of the prior epoxy resin and prepreg thereof.

The technical problem of the invention is mainly solved by the following technical scheme:

a mixed crystal type naphthol AS organic pigment is composed of two organic pigment molecules Ia and Ib, wherein R in Ib molecule₁，R₂And R₃Can be one or more of alkyl, alkoxy, nitro, halogen or heterocycle, and the structural formula of I is as follows:

I_1-6the powder X-ray diffraction pattern of (A) shows a characteristic diffraction peak at 6:

wherein Ia represents the molecular structural formula of the organic pigment red 146, Ib represents the molecular structural formula of the second component, and R in Ib molecule₁,R₂And R₃Represents a substituent which may be an alkyl group, an alkoxy group, a nitro group, a halogen group or a heterocyclic group. The product I obtained_1-6Compared with the hue angle of Ia, the hue angle of (A) is obviously enlarged, and the requirements of different application chromatograms can be met. Other color properties, as shown in Table-1, such as a color strength index K/S of greater than 21.42 for pigment Red 146 and a chroma index C of greater than 62.8 for pigment Red 146, are superior to the corresponding properties for pigment Red 146. In addition, through process optimization, the harmful impurity haematochrome KD in the obtained product is less than or equal to 100ppm, and the content of 4-chloro-2, 5-dimethoxyaniline or other substituted arylamine is less than or equal to 150ppm, so that the application safety of the product in the fields of human body contact and food packaging is ensured, and the product is an ideal colorant for packaging ink, digital ink jet, plastics and special ornaments.

Table one: i is_1-6Color and application property data (Ia: Ib ═ 1:1 mixed coupling products)

To achieve the object of the present invention, the inventors provide the following technical solutions according to the following chemical reaction equations:

a preparation method of mixed crystal type naphthol AS organic pigment comprises the following steps:

the preparation method of I has three methods:

a. hybrid coupling method: diazotizing 3-amino-4-methoxybenzoyl aniline, and then carrying out coupling reaction on the diazotized 3-amino-4-methoxybenzoyl aniline, the coupling component 2 ', 5 ' -dimethoxy-4 ' -chloro-3-hydroxy-2-naphthoyl aniline of Ia and the coupling component naphthol AS and derivatives thereof of Ib in a mixture with a molar ratio of 100:1 to 1:1 in water in the presence of a surfactant with an HLB value of 15-18, and heating, filtering, rinsing, drying and grinding the obtained pigment suspension to obtain I;

the inventors have found that controlling the end point of the reaction by thin layer chromatography ensures that the unreacted red base KD is present in the product in an amount of less than 100ppm and also reduces its self-coupling reaction in the diazonium salt solution, which generally has a negative effect on the shading and boiling resistance properties of the pigment. Preferably, the thin layer chromatography is performed by using a fluorescent silica gel plate as a thin layer plate, methanol/toluene (3: 1) as a developing agent, and an ultraviolet light source with the wavelength of 254nm as an observation light source, wherein the sample is spotted every 15 minutes until the spot at the Rf of 0.5 disappears as the reaction end point.

The inventor researches and discovers that the coupling components IV and V can be increased by using a surfactant with the HLB value of 15-18 as a coupling assistant agent_1-6The solubility in water ensures that the coupling reaction is completely carried out, and 4-chloro-2, 5-dimethoxyaniline or other arylamine is avoided from being generated due to the hydrolysis of the coupling component in the post-processing procedure, so that the content of the hydrolysis products in the pigment product is less than or equal to 150ppm, and the safety of the product in food contact application is ensured. As a preferred scheme, the surfactant which can be used is polysorbate, polyoxyethylene fatty acid ester or fatty alcohol polyoxyethylene ether; the amount of the surfactant is 1-12% of the pigment content.

The inventors have found that, in the mixed coupling process, the coupling components IV and V are adjusted_1-6The molar ratio of (A) to (B) can obtain products with different color strength, saturation, glossiness and transparency. The adjustment range is from 100:1 to 1: 1. Preferably, the transparency and gloss are highest at a molar ratio of 1: 1.

b. Coating coupling method: diazotizing 3-amino-4-methoxybenzoyl aniline, firstly coupling with a certain amount of coupling component naphthol AS of Ib and derivatives thereof in the presence of a surfactant with an HLB value of 15-18, then coupling with coupling component 2 ', 5 ' -dimethoxy-4 ' -chloro-3-hydroxy-2-naphthoyl aniline of Ia, and heating, filtering, rinsing, drying and grinding the obtained pigment suspension to obtain I;

the inventors have found that the product obtained by this coupling process, in addition to an improvement in shade, has a resistance which is more favourable to the properties of the pigment corresponding to the second coupling component than the pigment corresponding to the two coupling components. Preferably, a product with good boiling resistance can be obtained by using IV as the second coupling component and V₆As the second coupling component, a product having good solvent resistance can be obtained.

c. A mixing and grinding method: diazotizing two parts of 3-amino-4-methoxybenzoyl aniline, then respectively mixing the diazotized two parts of 3-amino-4-methoxybenzoyl aniline with a coupling component of 2 ', 5 ' -dimethoxy-4 ' -chloro-3-hydroxy-2-naphthoyl aniline and a coupling component of naphthol AS for synthesizing Ib and derivatives thereof to prepare a suspension or a filter cake of Ia and Ib, then uniformly mixing the suspension or the filter cake according to a molar ratio of 100:1 to 1:1, grinding the mixture to a fineness of less than or equal to 40 mu m by using a colloid grinder, and heating, filtering, rinsing, drying and grinding the mixture to obtain I.

The inventors have found that the products obtained in this way have better dispersibility in plastics colorations than the corresponding products Ia and Ib; and better storage stability in applications such as digital ink jet, packaging ink and paint tinting. Preferably, the mixing of Ia and Ib can be performed by a high-speed beater or a sand mill to achieve the effect of mixing the microcrystals. The mixture can be dried by spray drying, and the obtained pigment can be used without grinding.

Preferably, the diazotization reaction for preparing I is carried out in a water/inorganic acid medium, and the completeness of diazotization is monitored by adopting thin-layer chromatography, so that the diazotization reaction is ensured to be complete, and the content of diazotization components in a final product is less than or equal to 100 ppm.

Preferably, the coupling reaction for preparing I is carried out in an acid-out solution of the coupling component; the coupling reaction is completely carried out by adopting the coupling assistant agent, the content of unreacted coupling components in the obtained pigment is low, the condition that the content of 4-chloro-2, 5-dimethoxyaniline in the product exceeds 150ppm due to hydrolysis of the coupling components in the post-process is avoided, and the safety of the product in human contact and food packaging application is ensured.

Preferably, the molar ratio of Ia to Ib in I can be adjusted according to needs, so that the transmission rate is from 20 to 27, the gray degree is from 58 to 36, the definition is from 92 to 95, and the visual transparency is from 3 to 6 grades; the product with the color phase angle from 1 degree to 353 degrees can meet different application requirements.

The three different preparation methods can obtain products which can meet different requirements of customers on product transparency; the mixing and coupling method can prepare a high-transparency product which is suitable for manufacturing packaging ink; the coating coupling method can prepare a product with moderate transparency, and is suitable for manufacturing digital ink jet; the mixing method can prepare relatively covered products, and is suitable for coloring plastics and special decorative materials.

The invention relates to a mixed crystal type naphthol AS organic pigment and a preparation method thereof, and solves the problems of short operation time and poor flame retardance of the conventional epoxy resin and prepreg thereof.

Detailed Description

Below with I_1，The preparation of Ia: Ib ═ 1:1 is an example, illustrating the contents of the invention more specifically. It is to be understood that the practice of the present invention is not limited to the following examples, and that various changes or modifications may be made without departing from the scope of the invention.

In the invention, all parts and percentages are weight units, and all equipment, raw materials and the like can be purchased from the market or are commonly used in the industry, if not specifically indicated. Unless otherwise indicated, the examples employ methods that are within the ordinary skill in the art.