JP2009227708A - Polymer-coated pigment and method for producing it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer-coated pigment and a method for producing it showing good dispersion stability even in an organic solvent. <P>SOLUTION: The polymer-coated pigment has a natural resin-modified phenolic resin (B) soluble in a nonaqueous solvent and a polymer obtained by polymerizing at least one kind of polymerizable unsaturated monomer (C), which is soluble in the nonaqueous solvent and becomes insoluble or slightly soluble after the polymerization, on the surface of a pigment (A). In the method for producing the polymer-coated pigment, polymerization of at least one kind of the polymerizable unsaturated monomer (C), which is soluble in the nonaqueous solvent and becomes insoluble or slightly soluble after the polymerization, is carried out in the presence of the pigment (A), the nonaqueous solvent, and the natural resin-modified phenolic resin (B) soluble in the nonaqueous solvent. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a polymer-coated pigment having a polymer on the pigment surface.

Since pigments are generally insoluble colorants, it is an important issue to uniformly disperse pigment particles in a medium such as a solvent or resin in the production of paints, printing inks, color filters, etc. and the coloring of plastics. Yes.
Since the dispersibility of the pigment greatly depends on the properties of the surface of the pigment particles, attempts have been made to improve the dispersibility by various surface treatments. These treatment methods include rosin treatment, various surfactant treatments such as cationic surfactants, anionic surfactants, nonionic surfactants, pigment derivative treatments, and polymer treatments.

Among these treatment methods, polymer treatment methods for improving dispersibility by coating a pigment surface with a polymer include an in-situ polymerization method, a phase separation (coacervation) method, and a submerged drying method. .
Among them, the in-situ polymerization method is a conventionally performed method and is described in Patent Documents 1 to 7. All these methods are carried out under aqueous conditions. For example, in the methods described in Patent Documents 1 and 2, a polymer-coated pigment is obtained by polymerizing a monomer after stably dispersing the pigment in an aqueous medium using a surfactant or a water-soluble polymer. In the methods described in Patent Documents 3 and 4, a polymer-coated pigment is obtained using a polymerizable surfactant. In the method described in Patent Document 5, an alkylene oxide chain-containing compound having a polymerizable functional group is used, and a monomer is polymerized in a system in which the pigment is dispersed to obtain a polymer-coated pigment.
However, in any method, it is essential that the pigment can be stably dispersed in the aqueous medium, so that the usable pigment is limited, and the dispersion stability of the obtained polymer-coated pigment can be obtained only when the aqueous medium is used. In addition, there is a problem that dispersion stability cannot be obtained with an organic solvent.
The method described in Patent Document 6 is a method of obtaining a polymer-coated pigment by suspension polymerization using a dispersion stabilizer after mixing a pigment and a monomer, but in this method, a fine polymer-coated pigment cannot be obtained.
The method described in Patent Document 7 is a polymer-coated pigment obtained by polymerizing monomers in the presence of a pigment whose surface is previously covered with a silane coupling agent in a coexisting medium of a hydrophilic organic solvent and water. Is the method. However, it cannot be applied to organic pigments that are not compatible with silane coupling agents.

Examples of in-situ polymerization methods that do not use water as a solvent are described in Patent Documents 8 to 13. All of these are subjected to in-situ polymerization in a non-aqueous solvent having a dielectric constant of 1.5 to 20 and a surface tension of 15 to 60 mN / m. However, none of the methods described in this document is general-purpose because it is essential to use a surface-treated pigment and stably disperse the pigment with a specific dispersion stabilizer.
JP 2004-189928 A JP 2004-189929 A Japanese Patent Laying-Open No. 2005-097517 Japanese Patent Laid-Open No. 10-316909 JP 2004-155818 A Japanese Patent Laid-Open No. 13-72887 JP 2005-120365 A Japanese Patent Laid-Open No. 2004-2501 Japanese Patent Laid-Open No. 2004-18736 JP 2004-35592 A JP 2004-083660 A, JP 2004-107523 A, JP 2004-107524 A

  As described above, various methods have been used for the in-situ polymerization method, but it is applicable to general-purpose pigments, and further, a method for obtaining a polymer-coated pigment exhibiting good dispersion stability even with an organic solvent has not yet been obtained. is the current situation.

  An object of the present invention is to provide a polymer-coated pigment exhibiting good dispersion stability even with an organic solvent and a method for producing the same.

  As a result of intensive studies to solve the above problems, the present inventors have found that a polymer-coated pigment having a specific natural resin-modified phenol resin and a specific polymer on the pigment surface exhibits good pigment dispersibility, The present invention has been completed.

The polymer-coated pigment of the present invention is at least one which is soluble in the non-aqueous solvent and insoluble or hardly soluble after polymerization in the presence of the pigment, the non-aqueous solvent, and the natural resin-modified phenol resin soluble in the non-aqueous solvent. It can be obtained by so-called in-situ polymerization in which a kind of polymerizable unsaturated monomer is polymerized.
Conventionally, the in-situ polymerization method has been considered to require a polymerization field in which the pigment is finely and stably dispersed in the dispersion stabilizer. In the present invention, the surface of the pigment is wetted with the natural resin-modified phenol resin. As a result, the interface between the formed pigment and the natural resin-modified phenol resin soluble in the non-aqueous solvent is considered to be the place of polymerization, and the place where the pigment is finely and stably dispersed in the dispersion stabilizer is not essential. The surface treatment of the pigment to form a finely dispersed state is not always necessary, and can be applied to a wide variety of pigments.

  That is, the present invention provides at least one kind of natural resin-modified phenolic resin (B) soluble in a non-aqueous solvent and non-aqueous solvent and insoluble or hardly soluble after polymerization on the surface of the pigment (A). A polymer-coated pigment having a polymer obtained by polymerizing a polymerizable unsaturated monomer (C) is provided.

  In addition, the present invention is soluble in the non-aqueous solvent and insoluble or difficult after polymerization in the presence of the pigment (A), the non-aqueous solvent, and the natural resin-modified phenol resin (B) soluble in the non-aqueous solvent. The present invention provides a method for producing a polymer-coated pigment in which at least one polymerizable unsaturated monomer (C) that is dissolved is polymerized.

Since the polymer-coated pigment of the present invention exhibits good dispersion stability even in an organic solvent, the organic coating solvent such as paint, plastic, printing ink, rubber, leather, textile printing, color filter, jet ink, thermal transfer ink and the like is used as a solvent. It is very useful as a coloring material.
In addition, the method for producing a polymer-coated pigment of the present invention can be applied to general-purpose pigments regardless of whether they are untreated pigments, treated pigments, or organic / inorganic.

(Pigment (A))
The pigment (A) used in the present invention is at least one pigment selected from known and commonly used organic pigments or inorganic pigments. In addition, the present invention can be applied to either an untreated pigment or a treated pigment.

Examples of organic pigments include perylene / perinone compound pigments, quinacridone compound pigments, phthalocyanine compound pigments, anthraquinone compound pigments, phthalone compound pigments, dioxazine compound pigments, isoindolinone compound pigments, methine / azomethine compounds Examples thereof include compound pigments, diketopyrrolopyrrole compound pigments, insoluble azo compound pigments, and condensed azo compound pigments. Specific examples of the organic pigment are as follows, for example.
Examples of perylene / perinone compound pigments include C.I. I. PigmentViolet 29, C.I. I. Pigment Red 123, 149, 178, 179, C.I. I. Pigment Black 31, 32, C.I. I. Pigment Orange 43 and the like.
Examples of quinacridone compound pigments include C.I. I. Pigment Violet 19, 42, C.I. I. Pigment Red 122, 202, 206, 207, 209, C.I. I. Pigment Orange 48, 49 and the like.
Examples of the phthalocyanine compound pigment include C.I. I. Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, C.I. I. Pigment Green 7, 36 and the like.
Examples of the anthraquinone compound pigment include C.I. I. Pigment Blue 60, C.I. I. Pigment Yellow 24, 108, C.I. I. Pigment Red 168, 177, C.I. I. Pigment Orange 40 and the like.
Examples of the phthalone compound pigment include C.I. I. And pigments such as Pigment Yellow 138.
Examples of the dioxazine compound pigment include C.I. I. Pigment Violet 23, 37, and the like.
Examples of isoindolinone compound pigments include C.I. I. Pigment Yellow 109, 110, 173, C.I. I. Pigment Orange 61 and the like.
Examples of methine / azomethine compound pigments include C.I. I. Pigment Yellow 139, 185, C.I. I. Pigment Orange 66, C.I. I. Pigment Brown 38 and the like.
Examples of the diketopyrrolopyrrole compound pigment include C.I. I. Pigment Red 254, 255 and the like.
Examples of insoluble azo compound pigments include C.I. I. Pigment Yellow 1, 3, 12, 13, 14, 17, 55, 73, 74, 81, 83, 97, 130, 151, 152, 154, 156, 165, 166, 167, 170, 171, 172, 174, 175, 176, 180, 181, 188, C.I. I. Pigment Orange 16, 36, 60, C.I. I. Pigment Red5, 22, 22, 31, 112, 146, 150, 171, 175, 176, 183, 185, 208, 213, C.I. I. PigmentViolet 43, 44, C.I. I. Pigment Blue 25, 26 and the like.
Examples of the condensed azo compound pigment include C.I. I. Pigment Yellow 93, 94, 95, 128, 166, C.I. I. Pigment Orange 31C. I. Pigment Red 144, 166, 214, 220, 221, 242, 248, 262, C.I. I. Pigment Brown 41, 42 and the like.

  Examples of inorganic pigments include titanium oxide, zinc sulfide, lead white, zinc white, lithbon, antimony white, basic lead sulfate, basic lead silicate, barium sulfate, calcium carbonate, gypsum, silica, carbon black, iron black. , Cobalt violet, vermillion, molybdenum orange, red lead, bengara, yellow lead, cadmium yellow, zinc chromate, yellow ocher, chromium oxide, ultramarine, bitumen, cobalt blue and the like.

  In the present invention, an organic pigment is particularly preferable because the effects of the present invention can be further exerted. The quinacridone compound pigment, the phthalocyanine compound pigment, the insoluble azo compound pigment, and the condensed azo compound pigment can be used. It is particularly preferred to use it.

(Non-aqueous solvent)
The non-aqueous solvent used in the present invention is an organic solvent in which an aliphatic and / or alicyclic hydrocarbon solvent is essential. Examples of the aliphatic and / or alicyclic hydrocarbon solvents include n-hexane, n-heptane, “Loose” or “Mineral Split EC” manufactured by Shell Chemicals, and “Isopar C” manufactured by ExxonMobil Chemical. , “Isopar E”, “Isopar G”, “Isopar H”, “Isopar L”, “Isopar M”, “Naphtha 3”, “Naphtha 5” or “Naphtha 6”, products of Idemitsu Petrochemical Co., Ltd. “Solvent 7”, “IP Solvent 1016”, “IP Solvent 1620”, “IP Solvent 2028” or “IP Solvent 2835”, “Whitesol” of Japan Energy Co., Ltd., “ “Marcazole 8”, “AF Solvent No. 4” from Shin Nippon Oil Co., Ltd., “AF SO Vent No. 5 "," AF Solvent No. 6 "and" AF Solvent No. 7 ", and the like.

Moreover, you may mix and use another organic solvent in the range which does not impair the effect of this invention. Specific examples of such organic solvents include “Swazole 100 or 150” manufactured by Maruzen Petroleum Corporation, aromatic hydrocarbon solvents such as toluene or xylene; methyl acetate, ethyl acetate, acetic acid-n. Esters such as butyl or amyl acetate; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl amyl ketone or cyclohexanone; or alcohols such as methanol, ethanol, n-propanol, i-propanol or n-butanol Kind.
When mixed and used, the amount of the aliphatic and / or alicyclic hydrocarbon solvent used is preferably 50% by mass or more, and more preferably 60% by mass or more.

(Natural resin-modified phenolic resin (B) soluble in non-aqueous solvent)
The natural resin-modified phenolic resin (B) soluble in the non-aqueous solvent used in the present invention is a reaction product containing natural resins, a condensate of phenol and formaldehyde, and polyhydric alcohols as essential components.

  Examples of the natural resin include dammar, wood rosin, gum rosin, tall oil rosin, copal gum, balzam, sandalac, yakka gum, seed rack, refined shellac, decolorized shellac, white shellac, etc., among which wood resin, gum rosin The use of rosins such as tall oil rosin is preferred.

  The phenol-formaldehyde condensate is not particularly limited, and the phenols and formaldehyde are metal hydroxides such as sodium, potassium, calcium, magnesium, zinc, oxides, organic acid salts, aqueous ammonia solutions, and organic amine compounds. Examples thereof include condensates obtained by reacting in the presence of an alkali catalyst such as the above, resoles of novolak type phenol resins, and the like.

Examples of the phenols include phenol, cresol, amylphenol, p-tertiary butylphenol, p-octylphenol, p-nonylphenol, p-dodecylphenol, bisphenol A and the like. Among them, p-tertiary butylphenol, p- Alkylphenols having a substituent having 4 to 12 carbon atoms in the para position, such as octylphenol, p-nonylphenol, and p-dodecylphenol, are preferred.
Examples of formaldehyde include formalin and paraformaldehyde.

  Examples of the polyhydric alcohol include glycerin, diglycerin, trimethylolethane, trimethylolpropane, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol, sorbitol. Among them, glycerin and pentaerythritol are preferable.

As other reaction components when synthesizing the natural resin-modified phenol resin (B), animal and vegetable oils, animal and vegetable oil fatty acids and petroleum resins may be used. As animal and vegetable oils, palm oil, palm oil, rapeseed oil and soybean oil are used. , Hydrogenated soybean oil, linseed oil, tung oil, beef tallow, fish oil, etc. Examples include tooleic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, linolenic acid, eleostearic acid, arachidic acid, arachidonic acid, behenic acid, erucic acid and the like.
As petroleum resins, DCPD petroleum resins obtained from dicyclopentadiene (DCPD) raw materials such as cyclopentadiene and dicyclopentadiene, C5 petroleum resins obtained from C5 raw materials such as pentene, cyclopentene, pentadiene and isoprene, methylbutene, C9-based petroleum resins obtained from C9-based materials such as indene, methylindene, vinyltoluene, styrene, α-methylstyrene, β-methylstyrene, copolymerized petroleum resins composed of DCPD-based materials and C5-based materials, and DCPD-based materials Examples thereof include copolymerized petroleum resins composed of C9-based materials, copolymerized petroleum resins composed of C5-based materials and C9-based materials, and copolymerized petroleum resins composed of DCPD-based materials, C5-based materials, and C9-based materials.

  As the natural resin-modified phenol resin (B), for example, “Beccasite F-5501”, “Beccasite F-5503”, “Beccasite F-7301”, “Beccasite F-7304” of Dainippon Ink and Chemicals, Inc. And “Beccasite F-180”.

(At least one polymerizable unsaturated monomer (C) that is soluble in a non-aqueous solvent and becomes insoluble or hardly soluble after polymerization)
The at least one polymerizable unsaturated monomer (C) used in the present invention is soluble in a non-aqueous solvent and the polymer after polymerization becomes insoluble or hardly soluble in the non-aqueous solvent. For example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate or i-propyl (meth) acrylate, or (meth) acrylonitrile, styrene, ethyl vinylbenzene, vinyl acetate, vinyl chloride , Vinyl monomers having no reactive polar group (functional group) such as olefins such as vinylidene chloride, vinyl fluoride or vinylidene fluoride; (meth) acrylamide, dimethyl (meth) acrylamide, N- t-butyl (meth) acrylamide, N-octyl (meth) acrylamide, diacetone acrylate Amide-containing vinyl monomers such as amide, dimethylaminopropylacrylamide or alkoxylated N-methylolated (meth) acrylamides; dialkyl [(meth) acryloyloxyalkyl] phosphates or (meth) acryloyloxyalkyl acid phosphates Or dialkyl [(meth) acryloyloxyalkyl] phosphites or (meth) acryloyloxyalkyl acid phosphites; alkylene oxide adducts of the above (meth) acryloyloxyalkyl acid phosphates or acid phosphites Glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate and other epoxy group-containing vinyl monomers and phosphoric acid or phosphorous acid or their acidic esters Including phosphorus ester-containing vinyl monomers such as 3-chloro-2-acid phosphoxypropyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, di 2-hydroxyethyl fumarate or mono-2-hydroxyethyl monobutyl fumarate or polypropylene glycol or polyethylene glycol mono (meth) acrylate, or “Placcel FM, FA monomer” (die In addition to hydroxyalkyl esters of polymerizable unsaturated carboxylic acids such as caprolactone addition monomer manufactured by Cell Chemical Co., Ltd. or adducts of these with ε-caprolactone, (meth) acrylic acid, crotonic acid, maleic acid, Polymerizable unsaturated carboxylic acids such as unsaturated mono- or dicarboxylic acids such as fumaric acid, itaconic acid or citraconic acid, monoesters of these dicarboxylic acids with monohydric alcohols, Saturated carboxylic acid hydroxyalkyl esters and maleic acid, succinic acid, phthalic acid, hexahydrophthalic acid, tetrahydrophthalic acid, hensentricarboxylic acid, benzenetetracarboxylic acid, "Hymic acid", tetrachlorophthalic acid or dodecynyl succinic acid, etc. With polycarboxylic anhydride Various unsaturated carboxylic acids such as adducts and “Cardura E”, monoglycidyl esters of monovalent carboxylic acids such as coconut oil fatty acid glycidyl ester or octyl acid glycidyl ester, or butyl glycidyl ether, ethylene oxide, or propylene oxide Adducts with monoepoxy compounds such as, adducts of these with ε-caprolactone, or hydroxyl group-containing polymerizable unsaturated monomers such as hydroxy vinyl ether; dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) Dialkylaminoalkyl (meth) acrylates such as acrylate; glycidyl (meth) acrylate, (β-methyl) glucidyl (meth) acrylate, (meth) allyl glycidyl ether or polymerizable unsaturated carbo To various unsaturated carboxylic acids such as acids or equimolar adducts of a hydroxyl group-containing vinyl monomer such as mono-2- (meth) acryloyloxymonoethyl phthalate and the polycarboxylic anhydride, "Epicron 200", “Epicron 400”, “Epicron 441”, “Epicron 850” or “Epicron 1050” (epoxy resin manufactured by Dainippon Ink & Chemicals, Inc.), or “Epicoat 828”, “Epicoat 1001” or “Epicoat 1004” ( Japan Epoxy Resin Co., Ltd. Epoxy Resin), “Araldite 6071” or “Araldite 6084” (epoxy resin manufactured by Ciba-Geigy, Switzerland), or “Chisonox 221” [epoxy compound manufactured by Chisso Corporation], or "Denacol EX-611 [Epoxy group-containing polymerizable compounds obtained by addition reaction of various polyepoxy compounds having at least two epoxy groups in one molecule at an equimolar ratio such as epoxy compounds manufactured by Nagase Kasei Co., Ltd.] Epoxy group-containing polymerizable unsaturated monomers; such as 2-hydroxyethyl (meth) acrylate-hexamethylene diisocyanate equimolar adduct, and monomers having an isocyanate group and a vinyl group such as isocyanate ethyl (meth) acrylate Isocyanate group-containing α, β-ethylenically unsaturated monomers; vinyl ethoxysilane, α-methacryloxypropyltrimethoxysilane, trimethylsiloxyethyl (meth) acrylate, “KR-215, X-22-5002” (Shin-Etsu Arco such as silicon monomers such as Chemical Industry Co., Ltd. Cysyl group-containing polymerizable unsaturated monomers; and (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid and other unsaturated mono- or dicarboxylic acids, and these dicarboxylic acids Α, β-ethylenically unsaturated carboxylic acids such as monoesters of acid and monohydric alcohol, or 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, di-2-hydroxyethyl fumarate, Mono-2-hydroxyethyl-monobutyl Α, β-Unsaturated carboxylic acid hydroalkyl esters such as malate or polyethylene glycol mono (meth) acrylate and maleic acid, succinic acid, phthalic acid, hexahydrophthalic acid, tetrahydrophthalic acid, benzenetricarboxylic acid, benzenetetracarboxylic And carboxyl group-containing α, β-ethylenically unsaturated monomers such as acids, “hymic acids”, adducts with polycarboxylic acid anhydrides such as tetrachlorophthalic acid or dodecynyl succinic acid.
Among these, use of alkyl (meth) acrylates having 3 or less carbon atoms such as methyl (meth) acrylate and ethyl (meth) acrylate is preferable. Furthermore, in order to change the surface characteristics of the pigment surface and enhance the interaction with the pigment dispersant or pigment dispersion resin, at least one kind of carboxyl group, sulfonic acid group, phosphoric acid group, hydroxyl group, dimethylamino group, etc. It is preferable to copolymerize a polymerizable unsaturated monomer containing a functional group.
Moreover, in the range which does not impair the effect of this invention, you may use together general purpose monomers other than the said polymerizable unsaturated monomer (C). Examples of such a monomer include polymerizable unsaturated monomers that can be used other than the alkyl (meth) acrylate having an alkyl group having 4 or more carbon atoms and the alkyl (meth) acrylate described above. Can be mentioned.

  In addition, if part of the polymerizable unsaturated monomer (C) contains a partially crosslinkable monomer such as a polyfunctional polymerizable unsaturated monomer, the pigment will be eluted from the coated polymer. Still preferred. Examples of the polyfunctional polymerizable unsaturated monomer include divinylbenzene, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1 , 3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol dimethacrylate, trimethylolpropane triethoxytri (meth) Acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate Or allyl methacrylate.

The polymer-coated pigment of the present invention is soluble in the nonaqueous solvent and insoluble after polymerization in the presence of the pigment (A), the nonaqueous solvent, and the natural resin-modified phenol resin (B) soluble in the nonaqueous solvent. Alternatively, it is obtained by polymerizing at least one polymerizable unsaturated monomer (C) that is hardly soluble.
The pigment (A) and the natural resin-modified phenol resin (B) soluble in the non-aqueous solvent are preferably mixed before polymerization. As a mixing method, for example, a homogenizer, a disper, a bead mill, a paint shaker, a kneader, a roll mill, a ball mill, an attritor, a sand mill and the like can be used. In the present invention, the form of the pigment to be used is not limited, and any form of slurry, wet cake, and powder may be used. That is, in the production method of the present invention, even a pigment containing water such as a wet cake can be used.
After mixing the pigment (A) and the natural resin-modified phenol resin (B), a polymerizable unsaturated monomer (C) and a polymerization initiator described later are further mixed and polymerized to obtain a polymer-coated pigment. It is done.
At that time, the amount of the natural resin-modified phenol resin (B) used is not particularly limited since it is appropriately optimized according to the purpose, but usually 1 to 200 parts is used per 100 parts of the pigment (A). More preferably, it is 5-50 parts, More preferably, it is 5-30 parts.
Further, the amount of the polymerizable unsaturated monomer (C) used is not particularly limited because it is appropriately optimized depending on the purpose, but usually 1 to 200 parts per 100 parts of the pigment (A). More preferably 5 to 50 parts, still more preferably 5 to 30 parts.

  The total amount of the polymer obtained by polymerization of the natural resin-modified phenol resin (B) and the polymerizable unsaturated monomer (C) finally coated on the pigment is 100 parts of the pigment (A), 2 to 400 parts are preferably used, more preferably 10 to 100 parts, still more preferably 10 to 60 parts. At that time, it is preferable that at least one polymerizable unsaturated monomer (C) is usually used in a ratio of 10 to 400 parts, preferably 100 parts of the natural resin-modified phenol resin (B). Is 30 to 400 parts, more preferably 50 to 200 parts.

A method of polymerizing the polymerizable unsaturated monomer (C) in the presence of the pigment (A), the non-aqueous solvent, and the natural resin-modified phenol resin (B) is performed by a known and conventional polymerization method. Usually, it is carried out in the presence of a polymerization initiator. Such polymerization initiators include azobisisobutyronitrile (AIBN), 2,2-azobis (2-methylbutyronitrile), benzoyl peroxide, t-butyl perbenzoate, t-butyl-2-ethylhexano A radical generating polymerization catalyst such as ate, t-butyl hydroperoxide, di-t-butyl peroxide, or cumene hydroperoxide may be used alone or in combination of two or more.
Since some polymerization initiators are difficult to dissolve in the non-aqueous solvent system, the polymerization initiator is dissolved in the polymerizable unsaturated monomer (C), and mixed into the pigment (A) and the natural resin-modified phenol resin (B). The method of adding is preferred.
The polymerizable unsaturated monomer (C) or the polymerizable unsaturated monomer (C) in which the polymerization initiator is dissolved can be added by a dropping method in a state where the polymerization temperature is reached. A method of adding the polymer at a normal temperature before warming, heating the polymer after sufficiently mixing, and polymerizing is stable and preferable. The polymerization temperature is usually in the range of 60 ° C to 130 ° C. In addition, when the pigment (A) is an organic pigment, if the polymerization temperature is too high, the pigment may undergo significant changes in form such as alteration and crystal growth. In that case, it is preferable to polymerize at 70 to 100 ° C.

  After the polymerization, the nonaqueous solvent used for the polymerization is removed by filtration, followed by drying and pulverization to obtain a powdery polymer-coated pigment. Nutsche, filter press, etc. can be used for the filtration method. Moreover, it can dry with well-known drying apparatuses, such as a box-type dryer, a vacuum dryer, a band dryer, and a spray dryer. For the pulverization, a known pulverizer such as a mortar, a hammer mill, a disk mill, a pin mill, or a jet mill can be used.

  Hereinafter, the present invention will be described with reference to examples. Unless otherwise specified, “parts” and “%” are based on mass.

<Preparation of Reference Example 1 Rosin Modified Phenolic Resin Solution (B-1)>
In a four-necked flask equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen gas introduction tube, 100 parts of xylene was charged, and the temperature was raised to 120 ° C. At the same temperature, 100 parts of Becacite F-6303 (Dainippon Ink Chemical Co., Ltd. rosin modified phenolic resin) was added to the flask little by little and dissolved to give a 50% rosin modified phenolic resin solution (B-1). Obtained.

<Reference Example 2 Preparation of rosin-modified phenol resin solution (B-2)>
In the same manner as in Reference Example 1, 100 parts of Beccasite F-7303 (Rosin-modified phenol resin manufactured by Dainippon Ink & Chemicals, Inc.) was dissolved in 100 parts of xylene, and a 50% rosin-modified phenol resin solution (B-2) was dissolved. )

<Synthesis of Reference Example 3 Rosin-modified phenol resin solution (B-3)>
In a pressure reaction kettle equipped with a stirrer and a thermometer, 2060 parts of p-octylphenol was charged and dissolved by heating at 120 ° C. 350 parts of 92% paraformaldehyde powder (water content 8%) and calcium hydroxide 7.4 parts was added and heated to 130 ° C. and reacted for 2 hours to prepare a resol type phenol resin. The obtained resol type phenol resin had a polystyrene-reduced weight average molecular weight (Mw) of 900 as measured by GPC method.
A reaction kettle equipped with a stirrer, thermometer, condensed water separator and nitrogen inlet tube was charged with 1,000 parts of gum rosin having an acid value of 165 mgKOH / g and 98.5 parts of maleic anhydride, and the temperature was raised. When the temperature reached 200 ° C., 160 parts of pentaerythritol and 6 parts of calcium acetate were added, and the temperature was further raised to 280 ° C. Thereafter, when the acid value became 15 mgKOH / g or less at 280 ° C., the temperature was lowered to obtain a rosin ester resin. The obtained rosin ester resin had an acid value of 14.6 mgKOH / g, a softening point of 119 ° C., and a weight average molecular weight (Mw) of 1,600.
To a reaction kettle equipped with a stirrer, a thermometer, a condensed water separator and a nitrogen introduction tube, 40 parts of the resole-type phenol resin heated to 100 ° C. were added and stirred, and 100 parts of the rosin ester resin and Markaretz After charging 5 parts of M-845D [Aliphatic hydrocarbon resin (petroleum resin) manufactured by Maruzen Petrochemical Co., Ltd.] and 36.2 parts of AF Solvent No. 6 at 230 ° C. and keeping the same temperature. The temperature was adjusted to 200 ° C., and the reaction was terminated when the temperature was maintained at 200 ° C. for 1 hour to obtain a resin solution having a resin concentration of 80%.
When the same amount of toluene was added to the obtained resin solution, the Gardner viscosity at 25 ° C. was JK [the weight average molecular weight (Mw) of the resin was 150,000. 〕Met.
To 100 parts of the resin solution, 33.3 parts of linseed oil, 51 parts of AF Solvent No. 6 and 0.2 part of BHT (2,6-di-tert-butyl-4-methylphenol) were added. After stirring and mixing at 30 ° C. for 30 minutes, the ethyl acetoacetate aluminum dinormal butyrate is in the range of 0.5 to 5 parts at 160 ° C. so that the bubble viscosity at 25 ° C. is in the range of 4,500 to 7,000 dPa · s. The required amount was added and the mixture was heated and stirred for 1 hour to obtain a rosin-modified phenol resin solution (B-3).

<Synthesis of Reference Example 4 Rosin-modified phenol resin solution (B-4)>
In a reaction kettle equipped with a stirrer, thermometer, condensed water separator and nitrogen introduction tube, 100 parts of the rosin ester resin obtained in Reference Example 3 heated to 170 ° C. and 25 parts of soybean oil were charged. 48 parts of the resol-type phenol resin obtained in Reference Example 1 heated to 110 ° C. was added, the temperature was raised, and the reaction was carried out at 180 ° C. for 4 hours. The obtained resin composition was solid at room temperature. When the same amount of toluene was added to this solid resin composition, the Gardner viscosity at 25 ° C. was GH [weight average molecular weight (Mw) of the resin was 110,000. 〕Met.
78.6 parts of soybean oil, 44.4 parts of AF Solvent No. 6 and 0 of BHT (2,6-di-tert-butyl-4-methylphenol) with respect to 173 parts of the obtained solid resin composition After adding 6 parts and stirring and mixing at 180 ° C. for 30 minutes, ethyl acetoacetate aluminum diester which is a gelling agent at 160 ° C. so that the bubble viscosity at 25 ° C. falls within the range of 5,500 to 10,000 Pa · s. A normal amount of normal butyrate was added in the range of 0.5 to 4 parts, and the mixture was heated and stirred for 1 hour to obtain a rosin-modified phenol resin solution (B-4).

<Comparative Reference Example 1>
A four-necked flask equipped with a thermometer, a stirrer, a reflux condenser and a nitrogen gas inlet tube was charged with 800 parts of butyl acetate and heated to 90 ° C. When the temperature reached that temperature, 500 of 2-ethylhexyl methacrylate was added. Parts, 500 parts of macromonomer AS-6 (Toa Gosei Co., Ltd. polystyrene macromonomer, molecular weight 6000), 200 parts of butyl acetate, 10 parts of 2,2'-azobis (2-methylbutyronitrile) Was added dropwise over 5 hours, and after completion of dropping, the reaction was continued for 12 hours at the same temperature to obtain a poly (2-ethylhexyl methacrylate) -polystyrene graft copolymer.

<Comparative Reference Example 2>
A four-necked flask equipped with a thermometer, stirrer, reflux condenser and nitrogen gas inlet tube was charged with 900 parts of heptane and 100 parts of butyl acetate, heated to 90 ° C., and when the same temperature was reached, acrylic A mixture of 1000 parts of butyl acid and 10 parts of 2,2′-azobis (2-methylbutyronitrile) was added dropwise over 5 hours, and after completion of the addition, the reaction was continued for 10 hours at the same temperature. As a result, a homopolymer of butyl acrylate was obtained.

<Synthesis of Example 1 Polymer Coated Pigment (1)>
222 parts of wet cake (pigment content 45%) of Fast Gen Blue TGR (Dai Nippon Ink Chemical Co., Ltd.), 20 parts of rosin modified phenolic resin solution (B-1) of Reference Example 1, 1.25 mm 600 parts of zirconia beads and 300 parts of heptane were placed in a polyethylene jar and mixed for 60 minutes with a paint shaker (Toyo Seiki Co., Ltd.). After dilution with 300 parts of heptane, the zirconia beads were removed to prepare a pigment mixture.
400 parts of the obtained pigment mixed solution was charged into a separable flask equipped with a thermometer, a stirrer, a reflux condenser and a nitrogen gas introduction tube, and then 1 part of t-butylacrylamide sulfonic acid was added to 20 parts of ion-exchanged water. In addition, 2.2 parts of methyl methacrylate and 1.7 parts of ethylene glycol dimethacrylate were added to a polymerizable monomer composition of 2,2′-azobis (2-methylbutyronitrile). One part dissolved and 200 parts heptane were added. After stirring for 30 minutes at room temperature, the temperature was raised to 80 ° C., and the reaction was continued for 15 hours at the same temperature. After cooling, the polymer-treated pigment and the polymerization solvent were separated by filtration. The obtained polymer pigment was dried with a hot air dryer at 100 ° C. for 5 hours and then pulverized with a pulverizer to obtain a polymer-coated pigment (1).

<Synthesis of Examples 2-11 Polymer Coated Pigments (2) to (7)>
Implemented except changing the pigment (A) used, the rosin-modified phenol resin (B) solution, the non-aqueous solvent used during dispersion, and the non-aqueous solvent used during removal after dispersion as shown in Tables 1 and 2. In the same manner as in Example 1, a pigment mixed solution was prepared.
In the same manner as in Example 1 except that 400 parts of the obtained pigment mixed solution was used and the polymerizable monomer (C) was changed as shown in Tables 1 and 2, the polymer-coated pigment (2 ) To (7) were obtained.

In Table 1,
Marcazole 8 is isooctane (a hydrocarbon solvent manufactured by Maruzen Petrochemical)
Fast Gen Blue TGR (wet cake) C.I. I. Pigment Blue 15: 3 (Dai Nippon Ink Chemical Co., Ltd. Blue Pigment) Pigment component 45.0%
Shimla Brilliant Carmine 6B300 (powder) C.I. I. Pigment Red 57: 1 (Dai Nippon Ink Chemical Co., Ltd. Red Pigment)
Shimla Brilliant Carmine 6B300 (wet cake) C.I. I. Pigment Red 57: 1 (Dai Nippon Ink Chemical Co., Ltd. Red Pigment) Pigment component 40.0%
Fast Gen Green S (wet cake) C.I. I. Pigment Green 7 (Green pigment manufactured by Dainippon Ink and Chemicals, Inc.) Pigment component 46%
Shimla First Yellow 4400T (powder) C.I. I. Pigment Yellow 14 (Dai Nippon Ink Chemical Co., Ltd. yellow pigment)
Typeke CR-93 (powder) titanium oxide (rutile titanium oxide pigment made by Ishihara Sangyo Co., Ltd.)
Divinylbenzene contains 55% ethyl vinylbenzene (structural isomer) at 55%.
Polymerization initiator 1: 2,2′-azobis (2-methylbutyronitrile)
Polymerization initiator 2: t-butylperoxy-2-ethylhexanoate

In Table 2,
Marcazole 8 is isooctane (a hydrocarbon solvent manufactured by Maruzen Petrochemical)
Fast Gen Blue TGR (wet cake) C.I. I. Pigment Blue 15: 3 (Dai Nippon Ink Chemical Co., Ltd. Blue Pigment) Pigment component 45.0%
Shimla Brilliant Carmine 6B300 (powder) C.I. I. Pigment Red 57: 1 (Dai Nippon Ink Chemical Co., Ltd. Red Pigment)
Shimla Brilliant Carmine 6B300 (wet cake) C.I. I. Pigment Red 57: 1 (Dai Nippon Ink Chemical Co., Ltd. Red Pigment) Pigment component 40.0%
Fast Gen Green S (wet cake) C.I. I. Pigment Green 7 (Green pigment manufactured by Dainippon Ink and Chemicals, Inc.) Pigment component 46%
Shimla First Yellow 4400T (powder) C.I. I. Pigment Yellow 14 (Dai Nippon Ink Chemical Co., Ltd. yellow pigment)
Typeke CR-93 (powder) titanium oxide (rutile titanium oxide pigment made by Ishihara Sangyo Co., Ltd.)
Divinylbenzene contains 55% ethyl vinylbenzene (structural isomer) at 55%.
Polymerization initiator 1: 2,2′-azobis (2-methylbutyronitrile)
Polymerization initiator 2: t-butylperoxy-2-ethylhexanoate

<Comparative Example 1>
100 parts of powder (100% pigment content) of Fast Gen Blue TGR (Dai Nippon Ink Chemical Co., Ltd.), 20 parts of the graft copolymer obtained in Comparative Reference Example 1, 1.25 mm zirconia 600 parts of beads and 400 parts of heptane were placed in a polyethylene jar and mixed for 60 minutes with a paint shaker (Toyo Seiki Co., Ltd.). After dilution with 200 parts of heptane, the zirconia beads were removed. 400 parts of the obtained pigment mixture and 200 parts of heptane were charged into a separable flask equipped with a thermometer, stirrer, reflux condenser and nitrogen gas inlet tube, and then stirred into 8 parts of methyl methacrylate. A solution of 2 parts of 2,2′-azobis (2-methylbutyronitrile) was added. After stirring for 30 minutes at room temperature, the temperature was raised to 80 ° C., and the reaction was continued for 15 hours at the same temperature. After cooling, filtration was performed to obtain a polymer-coated pigment (H1). The filter paper was clogged and filtration took a long time. Moreover, precipitation of many polymer components was seen by the filtrate.

<Comparative Example 2>
100 parts of Fastgen Green S (Dai Nippon Ink Chemical Co., Ltd. green pigment) powder (pigment content 100%), 30 parts of butyl acrylate homopolymer obtained in Comparative Reference Example 2, 1.25 mm 600 parts of zirconia beads and 400 parts of heptane were placed in a polyethylene jar and mixed for 60 minutes with a paint shaker (Toyo Seiki Co., Ltd.). After dilution with 200 parts of heptane, the zirconia beads were removed. 400 parts of the obtained pigment mixed solution and 200 parts of heptane were charged into a separable flask equipped with a thermometer, a stirrer, a reflux condenser and a nitrogen gas introduction tube, and then 4 parts of methyl methacrylate and A solution of 2 parts of 2,2′-azobis (2-methylbutyronitrile) in 4 parts of ethylene glycol dimethacrylate was added. After stirring for 30 minutes at room temperature, the temperature was raised to 80 ° C., and the reaction was continued for 15 hours at the same temperature. After cooling, filtration was performed to obtain a polymer-coated pigment (H2). The filter paper was clogged and filtration took a long time. Moreover, precipitation of many polymer components was seen by the filtrate.

<Application example 1>
A solution obtained by dissolving 5 parts of the polymer-coated pigment (1) obtained in Example 1 and 2.1 parts of Ajisper PB-821 (a pigment dispersant manufactured by Ajinomoto Fine Techno Co., Ltd.) in 21.4 parts of ethyl acetate, 125 parts of 1.25 mm zirconia beads were placed in a polyethylene jar and dispersed for 2 hours with a paint shaker (Toyo Seiki Co., Ltd.). After adding 7.1 parts of ethyl acetate and removing the zirconia beads, the bar coater no. 6 was applied to the glass plate. As a result of measuring 60 ° gloss with a haze gloss meter (BYK Gardner product) after drying at room temperature for 10 hours, it was 92. The cyan density (OD value) measured by SpectroEye (product of GretagMacbeth) was 1.9, and the coating film showed good transparency and good pigment dispersibility. It was confirmed that

<Application examples 2 to 7>
Pigment dispersion, coating, and evaluation were performed in the same manner as in Application Example 1 except that the polymer coat pigment (1), the pigment dispersant, and the solvent were changed as shown in Table 3.

<Comparative application examples 1-5>
Pigment dispersion, coating, and evaluation were performed in the same manner as in Application Example 1 except that the pigment, pigment dispersant, and solvent were changed as shown in Table 4.

In Table 3,
Addisper PB-821: Ajinomoto Fine Techno Co., Ltd. pigment dispersant, 100% active ingredient
Disper BYK2050: BYK pigment dispersant, active ingredient 52%
X1: Shimla Brilliant Carmine 6B300 (powder) C.I. I. Pigment Red 57: 1 (Dai Nippon Ink Chemical Co., Ltd. Red Pigment)
X2: Fast Gen Green S C.I. I. Pigment Green 7 (Dai Nippon Ink Chemical Co., Ltd. Green Pigment)
X3: Shimla First Yellow 4400T: C.I. I. Pigment Yellow 14 (Dai Nippon Ink Chemical Co., Ltd. yellow pigment)

In Table 4,
Addisper PB-821: Ajinomoto Fine Techno Co., Ltd. pigment dispersant, 100% active ingredient
Disper BYK2050: BYK pigment dispersant, active ingredient 52%
X1: Shimla Brilliant Carmine 6B300 (powder) C.I. I. Pigment Red 57: 1 (Dai Nippon Ink Chemical Co., Ltd. Red Pigment)
X2: Fast Gen Green S C.I. I. Pigment Green 7 (Dai Nippon Ink Chemical Co., Ltd. Green Pigment)
X3: Shimla First Yellow 4400T: C.I. I. Pigment Yellow 14 (Dai Nippon Ink Chemical Co., Ltd. yellow pigment)

The coating films using the polymer-coated pigments (1) to (7) obtained in Examples 1 to 7 gave a very high gloss value of 85 or more in gloss, and were excellent in transparency (application) Example 6 shows a gloss value of 46, which is lower than that of the other application examples, because the gloss value of the pigment “Shimler First Yellow 4400T” itself used is low. These results show that the dispersibility is excellent. The coating film using the polymer coat pigments (H1) to (H2) obtained in Comparative Examples 1 and 2 had low gloss and poor transparency. This indicates that the dispersibility is poor.

The polymer-coated pigment obtained by the production method of the present invention can be used as a coloring material for paint, plastic, printing ink, rubber, leather, textile printing, color filter, jet ink, thermal transfer ink, and the like.

Claims (5)

On the surface of the pigment (A), a natural resin-modified phenol resin (B) soluble in a non-aqueous solvent and at least one polymerizable unsaturated monomer that is soluble in a non-aqueous solvent and becomes insoluble or hardly soluble after polymerization. A polymer-coated pigment comprising a polymer obtained by polymerizing the body (C). In the presence of the pigment (A) and the natural resin-modified phenol resin (B) soluble in a non-aqueous solvent, at least one polymerizable unsaturated that is soluble in the non-aqueous solvent and insoluble or hardly soluble after polymerization The polymer-coated pigment according to claim 1, obtained by polymerizing the monomer (C). The polymer-coated pigment according to claim 1 or 2, wherein the non-aqueous solvent includes an aliphatic hydrocarbon solvent and / or an alicyclic hydrocarbon solvent. In the presence of the pigment (A), a non-aqueous solvent and a natural resin-modified phenol resin (B) soluble in the non-aqueous solvent, at least one kind which is soluble in the non-aqueous solvent and becomes insoluble or hardly soluble after polymerization A method for producing a polymer-coated pigment, which comprises polymerizing a polymerizable unsaturated monomer (C). The method for producing a polymer-coated pigment according to claim 4, wherein the non-aqueous solvent includes an aliphatic hydrocarbon solvent and / or an alicyclic hydrocarbon solvent.