JPH0512369B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a branched resin that has low viscosity and excellent compatibility with alkyd resins, polyester resins, and resins other than these resins, and also has excellent effects as a resin for dispersing various pigments. Prior Art In accordance with the recent social needs for low pollution and energy saving, it is preferable that the amount of solvent contained in paints be as small as possible, and it has therefore been necessary to develop resins with low viscosity for the same non-volatile content. For this reason, alkyd resins and polyester resins, which can easily be reduced in molecular weight, are generally used as resins for high non-volatile resins.
However, conventional methods for reducing the viscosity of these resins include reducing the molecular weight of the resin itself,
Alternatively, a common method has been to blend raw materials with good solubility, but the former method has the disadvantage that durability such as weather resistance and chemical resistance of these resins is reduced. On the other hand, since the latter method uses raw materials with good solubility, it has the drawbacks of reduced solvent resistance and reduced mechanical strength. The present inventors focused on the fact that such conventional techniques do not take into account the three-dimensional structural factors of resins, and developed a method for reducing resin viscosity using resin compositions commonly used for paints and without significantly lowering the molecular weight. The present invention has been developed after intensive research into methods for reducing this. The novel alkyd or polyester resin of the present invention uses a polyfunctional epoxy compound having two or more glycidyl groups as a core material, and combines the glycidyl group of the epoxy compound as the core material with the alkyd or polyester resin having a carboxyl group. By carrying out an addition reaction with a polymer, a radial structure having an epoxy compound as a core can be provided. It is therefore believed that low viscosity can be achieved in such novel alkyd or polyester resins due to the solubility of the polyfunctional epoxy compound serving as the core material and the radial structure of the resin molecules. On the other hand, in the paint industry, paints are rarely formulated using only one type of resin, and usually plasticizers,
Various resins are mixed and used as crosslinking agents and modifiers. In this case, if the resins have good compatibility with each other, the desired low viscosity and improved pigment dispersibility can be achieved, but if the compatibility is poor, the intended results may not necessarily be obtained. There is. Problems to be Solved by the Invention Therefore, regardless of the type of resin used, it has excellent compatibility, maintains a low viscosity even in a mixed state, has good pigment dispersibility, and has a low viscosity. Therefore, it would be of great benefit to the industry if a high non-volatile paint with excellent coating workability and film performance could be obtained, and the main purpose of the present invention is to provide such a paint resin. It is. As a means of improving compatibility with various resins, the present inventors introduced some resin molecules that cause compatibility problems into resin molecules, and by configuring new molecules, the compatibility was improved. The present invention was completed based on this fact. Means for Solving the Problems The purpose of the present invention is to A polyfunctional epoxy compound represented by the formula A group obtained by reacting at least one prepolymer other than an acrylic resin having a carboxyl group represented by the formula This can be achieved using a branched resin represented by By introducing the resin component Y into the branched resin of the present invention, the compatibility with various resins that are incompatible with X but compatible with Y is improved. Further, for the purpose of improving the pigment dispersibility, paint, painting, and coating performance of such resins, the branched resins may be made to carry an electron-accepting group and/or an electron-donating group. To explain in detail the method for producing the above-mentioned branched resin, the carboxyl group-containing polyester prepolymer represented by 2) Obtained by condensation of polycarboxylic acid and polyhydric alcohol. The oxycarboxylic acids that can be used in the case of (1) above include m-hydroxybenzoic acid, 2-hydroxycyclohexanecarboxylic acid, 2-hydroxy-m-
-toluic acid, 3hydroxy-O-toluic acid,
6-hydroxy-m-toluic acid, 2-hydroxy-
1-naphthoic acid, O-hydroxyphenylacetic acid, m
-Hydroxyphenylacetic acid, p-hydroxyphenylacetic acid, 3-hydroxy-3-phenylpropionic acid, 3-(O-hydroxyphenyl)propionic acid, lactic acid, 2-hydroxybutyric acid, benzylic acid, mandelic acid, 12-hydroxystearin Examples include acids. On the other hand, in the above case, aromatic carboxylic acids, alicyclic carboxylic acids, aliphatic carboxylic acids, partially saturated alicyclic carboxylic acids, and the like are used as the polycarboxylic acids. As such aromatic carboxylic acids, phthalic anhydride, tetrahydroisophthalic acid, terephthalic acid, trimellitic anhydride, pyromellitic anhydride, etc. are used, and monocarboxylic acids such as benzoic acid and pt-butylbenzoic acid are also used depending on the molecular weight. Used as a conditioning agent. Examples of alicyclic carboxylic acids include 1,1-cyclohexanedicarboxylic acid,
Examples thereof include hexahydrophthalic acid (anhydride), 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, methylhexahydrophthalic acid (anhydride), hexahydrotrimellitic acid and acid anhydrides thereof. Furthermore, dimethyl ester of the above-mentioned saturated alicyclic polybasic acid and the like can also be used by transesterification. Furthermore, aliphatic carboxylic acids or partially saturated alicyclic carboxylic acids include succinic acid (and its acid anhydrides), adipic acid, azelaic acid, sebacic acid, tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, hectic anhydride,
Hymic anhydride, maleic anhydride, fumaric itaconic acid, methylcyclohexcentric carboxylic anhydride, etc. can be used. On the other hand, the polyhydric alcohol component, which has traditionally been used to form polyester, can be used.
For example, ethylene glycol, diethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol,
1,4-butylene glycol, 1,6-hexanediol, 1,5-pentanediol, 2,5-
Hexanediol, trimethylolethane, trimethylolpropane, glycerin, pentaerythritol, diglycerin, sorbitol, 1,4
-cyclohexanedimethanol and the like. A commonly used condensation reaction method is used to synthesize such polyester resins. Furthermore, the alkyd resin can be obtained by adding an oil or fat component to the raw materials used in the synthesis of the polyester resin and performing transesterification, condensation reaction, or the like. Such oil and fat components include fatty acids such as soybean oil fatty acids, castor oil fatty acids,
Tall oil fatty acids, coconut oil fatty acids, cottonseed oil fatty acids, etc., or vegetable oils such as soybean oil, castor oil, etc.
Tall oil, coconut oil, cottonseed oil, linseed oil, etc. are used. The amount of carboxyl groups contained in the resin of the polyester or alkyd prepolymer X-COOH having carboxyl groups is on average 0.1 mol to 1.5 mol per molecule, preferably 0.2 mol to 1.2 mol, calculated based on the number average molecular weight. . When the amount of carboxyl groups exceeds 1.5 mol, the viscosity of the branched resin increases,
Moreover, if it is less than 0.1 mole, a sufficient branched structure cannot be obtained, and the object of the present invention cannot be achieved. The alkyd or polyester prepolymer having a carboxyl group synthesized as described above can be used without impairing the durability such as weather resistance, chemical resistance, solvent resistance, and mechanical strength of the alkyd or polyester resin that is the object of the present invention. In order to maintain the viscosity, the weight average molecular weight of the alkyd or polyester prepolymer (measured by gel permeation chromatography, converted to polystyrene) is 500~
50,000, and preferably has a glass transition temperature of -20 to 100°C. On the other hand, examples of the prepolymer Y-COOH include carboxyl group-containing alkyd or polyester resins, fluororesins, silicone resins, and the like. In addition, in polyhydroxy resins such as polyether resins, polyurethane resins, and epoxy resins, such hydroxyl groups are converted to acid anhydrides, such as acetic anhydride, succinic anhydride, phthalic anhydride, maleic anhydride, tetrahydrophthalic anhydride, and hexahydroanhydride. At least one type of phthalic acid can be added by a conventional method to make the resin contain a carboxyl group, and then the resin can be used. The above polyether resin is a polyhydroxy compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, sorbitol, pentaerythritol,
It is a resin obtained by polymerizing propylene oxide or the like using an initiator such as sucrose or starch. Polyurethane resins are obtained by addition-reacting polyhydroxy resins, such as oil-free polyester resins having hydroxyl groups, long oil or short oil alkyd resins, acrylic resins or polyether resins, and isocyanate compounds. Epoxy resins can generally be obtained by reacting a phenolic compound and epichlorohydrin, a polyhydric alcohol and epichlorohydrin, or an organic acid and epichlorohydrin. The amount of carboxyl groups contained in the resin of the prepolymer having carboxyl groups, Y-COOH, is 0.1 mol to 1.5 mol per molecule on average, calculated based on the number average molecular weight.
The molar amount is preferably 0.2 mol to 1.2 mol. If the amount of carboxyl groups exceeds 1.5 mol, the viscosity of the branched resin increases, and if it is less than 0.1 mol, a sufficient branched structure cannot be obtained, and the object of the present invention cannot be achieved. Alkyd or polyester prepolymers containing carboxyl groups synthesized under these conditions, X-COOH and resins other than acrylic resins containing carboxyl groups, Y-COOH is a polyfunctional epoxy compound containing two or more glycidyl groups. By carrying out an addition reaction with a glycidyl group, a branched resin having low viscosity and good compatibility, which is the object of the present invention, can be synthesized. The above-mentioned polyfunctional epoxy compound is a substance having two or more glycidyl groups, and these compounds may be saturated or unsaturated aliphatic, alicyclic, aromatic or heterocyclic compounds, and chlorine, They may be substituted with substituents such as hydroxyl groups and ether groups, and these compounds may be monomers or polymers. The polyfunctional epoxy compounds of the present invention include epoxidized esters of unsaturated monohydric alcohols with polyvalent aliphatic acids, such as di(2,3-epoxyhexyl adipate) and di(2,3-epoxyhexyl oxalate). epoxybutyl), di(2,3-epoxyhexyl) succinate, di(2,3-epoxybutyl) phthalate
and glycidyl group-containing nitrogen compounds such as diglycidylaniline, di- and triglycidylamine, etc. Particularly preferred polyfunctional epoxy compounds for use in the preparation of the novel alkyd or polyester resins of the invention are glycidyl ethers, especially glycidyl ethers of polyhydric phenols and polyhydric alcohols. Glycidyl ethers of polyhydric phenols and polyhydric alcohols can be obtained by reacting epirochlorohydrin with desired polyhydric phenols or polyhydric alcohols in the presence of an alkali. For example, diglycidyl ether of bisphenol A, diglycidyl ether of resorcinol, triglycidyl ether of phloroglucinol, triglycidyl ether of trihydroxydibiphenyl, phenol.
Polyglycidyl ether of formaldehyde novolac, polyglycidyl ether of O-cresol formaldehyde novolac, diglycidyl ether of butanediol, diglycidyl ether of polypropylene glycol, diglycidyl ether of neopentyl glycol, triglycidyl ether of glycerin, Triglycidyl ether of methylolpropane, tetraglycidyl ether of pentaerythritol, polyglycidyl ether of sorbitol, etc. Other polyfunctional epoxy compounds include epoxy compounds derived from aromatic dicarboxylic acids such as diglycidyl isophthalate, diglycidyl phthalate,
Also included are diglycidyl esters of linoleic dimer acid and triglycidyl isocyanurate, tetraphenylolethane epoxy, and the like. The reaction between the polyfunctional epoxy compound having two or more glycidyl groups and the carboxyl group-containing prepolymer and resin is based on the number of moles of glycidyl groups in the polyfunctional epoxy compound and the carboxyl group in the carboxyl group-containing prepolymer and resin. The number of moles is in the range of 1:0.6 to 1:1.4, preferably 1:
The ratio of the carboxyl group-containing prepolymer to the carboxyl group-containing resin other than the acrylic resin is 99 to 10 wt% of the former.
to 1 to 90 wt% of the latter, if necessary, add a solvent that does not react with glycidyl or carboxyl groups, and adjust the reaction temperature to 80 to 180°C, preferably 100 to 160°C.
C. until the reaction rate as measured by the acid value of unreacted carboxyl groups is 80% or more. For the reaction between the glycidyl group and the carboxyl group, for example, a base catalyst can be used as a reaction catalyst, if necessary. As a base catalyst,
For example, pyridine, isoquinoline, quinoline, N,
N-dimethylcyclohexylamine, α-picoline tri-n-butylamine, triethylamine,
N-ethylmorpholine, N,N-dimethylaniline, N-(β-hydroxyethyl)amine, N-
Organic amines such as ethyl-3,5-dimethylmorpholine and dimethyl coconut amine derived from coconut oil, etc., or inorganic alkalis such as caustic soda and caustic potash are used. The branched resin obtained by this method has improved compatibility with various resins, has a low viscosity of the resin itself, is a high non-volatile paint, and has excellent coating workability and film performance. can get. However, since pigments used in paints do not have uniform surface properties, the branched resins described above may not always exhibit good dispersion performance depending on the pigment. Based on the fact that the surface properties of pigments are classified based on the concepts of acids and bases, the present inventors have determined that the surface properties of pigments using the above-mentioned branched resin are acidic and/or based on the surface properties of pigments.
Or, by modifying it to basicity, the low viscosity property and good compatibility of the resin itself are taken into consideration, which improves the dispersion performance of various pigments, especially the dispersion speed, viscosity of the dispersion paste, and yield, compared to when ordinary acrylic resin is modified. It was discovered that it has excellent properties in terms of value, stability over time, stability of mixed colors in the paint state, non-volatile content during painting, workability of painting, color tone as a paint film, gloss, sharpness, etc. . Regarding branched resins for pigment dispersion having such excellent dispersion, paint, painting, and coating performance, (1) branched resins having electron-accepting groups contain acid anhydrides and/or By reacting with a sultone compound, a free electron-accepting group can be supported within the molecule. On the other hand, (2) a branched resin having an electron-donating group is produced by (a) condensing or adding a basic compound during the synthesis of a carboxyl group-containing alkyd or polyester prepolymer, and using a prepolymer that retains such a base; , can be obtained by synthesizing a branched resin. Furthermore, (b) reacting active hydrogen contained in the branched resin and an optionally introduced active alkoxy group with a basic low molecular weight compound and/or basic resin having an active alkoxy group and/or active hydrogen; Obtained by forcing. Furthermore, (3) the amphoteric branched resin having an electron-donating group and an electron-accepting group is
can be easily obtained in combination with In addition, "active hydrogen" used in this specification
The term refers to primary, secondary and tertiary hydroxyl groups,
It refers to a highly reactive hydrogen atom bonded to oxygen, sulfur, nitrogen, etc. contained in an amide bond, urethane bond, carboxyl group, etc. The term "active alkoxy group" refers to a highly reactive hydrogen atom bonded to oxygen, sulfur, nitrogen, etc. contained in an amide bond, urethane bond, carboxyl group, etc. "Functional group that reacts with active hydrogen" refers to highly reactive alkoxy groups such as substituted groups.
The term refers to primary, secondary and tertiary hydroxyl groups,
It refers to groups that easily react with active hydrogen, such as isocyanate groups and glycidyl groups, and the term "functional groups that react with active alkoxy" refers to groups that easily react with active alkoxy groups, such as primary, secondary, and tertiary hydroxyl groups. The term "electron-accepting group" refers to groups such as carboxyl, sulfone, and nitro groups that tend to withdraw electrons from others when hydrogen is used as the standard in the molecule. Because the term ``basic resin'' has -N¨- which has a lone electron, the term ``basic resin'' refers to groups that tend to donate electrons to others when hydrogen is the standard in the molecule, such as halogen and alkyl. The term ``basic low molecular weight compound'' refers to hydroxylamine compounds used as prepolymers or monomers of basic resins. (e.g. monoethanolamine, diethanolamine, aminopentanol, aminobenzyl alcohol, 2-dimethylaminoethanol, etc.), amino acids (e.g. 3-dimethylaminobenzoic acid, 2-amino-isobutyric acid, 4-amino-n-butyric acid, etc.) etc. In this application, (A) a branched resin having an electron accepting group, (B) a branched resin having an electron donating group, and (C) an amphoteric branched resin having an electron accepting group and an electron donating group are described in detail. explain. (A) When synthesizing a branched resin having an electron-accepting group, an active hydrogen group-containing compound is used to synthesize a resin other than the above-mentioned alkyd or polyester prepolymer having a carboxyl group and an acrylic resin having a carboxyl group. Active hydrogen may be retained in alkyd or polyester prepolymers and other resins, or resins other than alkyd or polyester prepolymers and acrylic resins that do not retain active hydrogen groups may be used. The branched resin obtained by reacting a polyfunctional epoxy compound with a resin other than an alkyd or polyester prepolymer having a carboxyl group and an acrylic resin having a carboxyl group has the formula: It holds a secondary hydroxyl group within the molecule and can be used as an active hydrogen group. In order to support an electron-accepting group on the branched resin that retains active hydrogen groups obtained by this method,
Any compound that reacts with active hydrogen to produce a free acidic group can be used, but typically compounds that react with active hydrogen to produce carboxyl groups, acid anhydrides, e.g. Acetic acid, succinic anhydride, phthalic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, trimellitic anhydride, etc., as well as compounds that react with active hydrogen groups to produce sulfonic acid groups, fatty acid sultones , such as 1,3-propanesultone, 1,3-butanesultone, 2,4-
Butanesultone, 1,4-butanesultone, 1,
It is also possible to use 3-octane sultone, 2,3-decane sultone, etc., or anhydrous inorganic acids such as metaphosphoric acid. In the addition reaction of such sultone compounds, a solution consisting of a branched resin and a fatty acid sultone is
A saltone-modified branched resin can be synthesized by reacting at a reaction temperature of 150°C for 2 to 10 hours. In the synthesis of such sultone-modified branched resin, the amount of sultone used when adding sultone is 0.01 to 6 in terms of solid content weight ratio of the branched resin.
% by weight, preferably in the range 0.02-4% by weight. If the amount used exceeds 6% by weight, the melt viscosity of the polymer increases, making it difficult to manufacture the polymer. On the other hand, in the synthesis of a branched resin having an electron-donating group (B), when synthesizing an alkyd or polyester prepolymer having a carboxyl group,
The following basic low molecular weight compounds, hydroxylamine compounds such as monoethanolamine, diethanolamine, aminopentanol, aminobenzyl alcohol, 2-dimethylaminoethanol, etc., and amino acids such as 3-dimethylaminobenzoic acid, 2-aminobutyric acid, 4-aminobutyric acid, etc. By reacting -amino-n-butyric acid or the like and synthesizing a branched resin using such a prepolymer, an electron donating group can be supported within the molecule. Alternatively, when synthesizing an alkyd or polyester prepolymer having a carboxyl group and a resin other than an acrylic resin having a carboxyl group, an active alkoxy group-containing compound and/or an active hydrogen group-containing compound as necessary are reacted with such a prepolymer and others. The branched resin synthesized using the resin is loaded with active hydrogen and an active alkoxy group introduced as necessary,
By reacting the branched resin obtained by this method with a low molecular weight basic compound and/or a basic resin, a branched resin having an electron donating group can be synthesized. In addition, a polyvalent isocyanate compound or a glycidyl compound is blended and reacted with a branched resin carrying an active hydrogen group so that free isocyanate groups or glycidyl groups remain, and a basic resin and/or a basic low molecular weight It can also be a branched resin that can react with active hydrogen in the compound. As the basic resin, urea resins, melamine resins, polyamide resins, polyurethane resins, etc., which are commonly used in the paint field, are used. Urea resins and melamine resins are obtained by condensing formaldehyde with urea or melamine, and alcohols (e.g. methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, etc.) are used as part of the raw materials for resin production, if necessary. , alkylated methylol urea resins or alkylated methylol melamine resins. Polyamide resin is obtained by a condensation reaction of an aliphatic diamine and a dibasic acid, or a urea condensation reaction of a cyclic lactam.
1,2 ethanediamine, N,N-dimethyl-1,
2-ethanediamine, 1,6-hexanediamine, etc., and dibasic acids such as succinic acid, adipic acid, and sebacic acid are appropriately selected. Examples of cyclic lactams include α-pyrrolidone, δ
-Caprolactam, ω-capryllactam, etc. are used. Such a basic resin can be introduced with an electron-donating group and an active hydrogen or active alkoxy group during the production process, and can undergo an addition or condensation reaction with the functional group in the acidic resin (A). The above (A) branched resin having an electron accepting group and (B)
(C) A branched resin having an electron accepting group and an electron donating group can be synthesized by combining the techniques used in the synthesis of a branched resin having an electron donating group. The branched resins (A), (B), and (C) obtained in this way have lower viscosity at the same molecular weight than when ordinary resins are loaded with electron-accepting groups and/or electron-donating groups using the same method. It has the characteristic that it becomes low. In addition, by appropriately using branched resins (A), (B), and (C) according to the pigment surface characteristics, we have achieved superior dispersion, paint, coating, and coating performance compared to when ordinary resins are modified. be effective. However, in the paint industry, a wide variety of inorganic and organic pigments are used.
Their surface characteristics are also very different. Pigment with acid,
Even when considered as a base, their acidity and basicity vary widely. Therefore, it is naturally expected that the degree of acidity and basicity in the dispersing resin will vary from pigment to pigment if the optimum one is sought for each pigment. Therefore, the present inventors thought that it might be possible for the acidity and basicity of the dispersion resin to exhibit good dispersibility in terms of the greatest common denominator for many of the pigments that are widely used today. was actually dispersed in the above-mentioned dispersing resin, and the relationship between the acidity and basicity of the resin and the dispersion effect of the pigment was investigated. However, since there is no known simple method for measuring the acidity and basicity of amphoteric pigments in a non-aqueous system, the present inventors dissolved the sample dispersion resin in aniline and used n-tetrabutylammonium hydroxide. The acidity of the resin is determined by the number of moles of the reagent required for neutralization, and the acidity of the resin is determined by non-aqueous potentiometric titration using perchloric acid as a titration reagent using the acetic acid solution of the sample. We have developed a unique method for measuring acidity and basicity in a non-aqueous system that determines basicity from the number of moles of reagent required for neutralization, and thereby evaluate the acidity and basicity of resins. did. As a result of the test, the present inventors found that the acidity of the amphoteric dispersion resin was 1.0 to 1.0×10 ⁻² mmol/g. solid,
Particularly preferably 0.8 to 2.0×10 ⁻² mmol/g. solid
The basicity is in the range of 1.0 to 5×10 ^-2 mmol/
g. solid, particularly preferably 1.0 to 1×10 ^-2 mmol/
g. It has been learned from experience that when the pigment is within the solid range, it exhibits good dispersibility for various inorganic and organic pigments for paints. Therefore, in preferred embodiments of the present invention, resins exhibiting acidity and basicity within the above ranges in the test method described herein are preferably used. As a result of our research, the present inventors have found that the blending ratio in the reaction between the active hydrogen groups in the branched resin (A) and the acid anhydride and/or sultone compound (B) is 99.9 to 99.9% based on the solid content of the resin. (B) 0.1 to 50% to 50%, most preferably (B) 0.1 to 30% to (A) 99.9 to 70%;
Further, the blending ratio in the reaction between (A) branched resin carrying the above active hydrogen group and optionally introduced active alkoxy group, and (B) low molecular weight basic compound and/or (B) basic resin. is the solid content of the resin (A) 99.9-50%, (B) 0.1-50%, most preferably (A) 99.9-70%, (B) 0.1-30%,
On the other hand, the weight ratio of the mixture in the reaction between the above branched resin and (B) basic resin is 99.5 to 40 in terms of the solid content of the resin (A).
% of (B) 0.5-60%, most preferably (A) 99.5
~60% and (B) 0.5~60%, and the molecular weight of the resulting dispersion resin measured by gel permeation chromatography was 2000~2000 in terms of polystyrene.
200,000, preferably from 4,000 to 100,000 and a glass transition temperature of -20 to 100°C, preferably -10 to 80°C, has also been found to give the best results.
Therefore, in the most preferred embodiment of the invention,
In addition to the acidity and basicity of the dispersing resin, a resin that satisfies the above various parameters is used for dispersing the pigment. The coating composition of the present invention is obtained by dispersing various pigments using the dispersing resin specified in the specification of the present application. In this case, various inorganic and organic pigments commonly used in paints are used as pigments, such as carbon black, zinc oxide titanium oxide, antimony white, iron black, red iron oxide, red lead, cadmium yellow, and sulfide. zinc, lithopone,
Barium sulfate, lead sulfate, barium carbonate, lead white, alumina white, etc., and organic pigments include azo, polycondensed azo, metal complex azo, benzimidazolone, phthalocyanine (blue, green), Various pigments of the thioindigo, anthraquinone, flavanthrone, indanthrene, anthrapyridine, pyranthrone, isoindolinone, perylene, perinone and quinacridone types are advantageously used. The blending ratio of the above-mentioned dispersing resin and pigment is not critical and can be selected arbitrarily since it is further diluted with resin or solvent when making a paint, but it is usually The ratio of resin (solid content) 10 to 90% by weight and pigment 90 to 10% by weight, preferably resin (solid content) 30 to 90% by weight.
It is used in a proportion of 70% by weight and 70-30% by weight of pigment. The coating composition of the present invention comprises a dispersing resin carrying the above-mentioned electron-accepting group and/or electron-donating group, and, if necessary, other resins such as acrylic resins, alkyd resins, polyester resins other than those of the present invention, One or more of polyether resin, cellulose nitrate, urethane resin, vinyl acetate resin, polyvinyl alcohol resin, vinyl chloride resin, phenol resin, melamine resin, guanamine resin, urea resin, epoxy resin, etc., and the above pigments. Solvents commonly used in the paint industry, such as hydrocarbon solvents such as toluene, xylene, Solbetsuso 100 and Solbetsuso 150, and ester solvents such as ethyl acetate and butyl acetate, if necessary. Add one or more ketone solvents such as , MEK, MIBK, etc., and use a regular dispersion machine such as a roll mill dispersion machine, ball mill dispersion machine, sand grind mill dispersion machine, planetary mixer, high speed disper dispersion machine, etc. manufactured using The coating composition thus obtained exhibits extremely good pigment dispersibility and is excellent in stability during storage and compatibility with various resins and solvents, making it extremely useful as a coating composition. The present invention will be explained below with reference to Examples. Parts and percentages are by weight unless otherwise specified. Synthesis Example 1 Branched resin with improved compatibility of two carboxyl group-containing polyester resins In-house polyester resin A (Mn=
2600, Mw=45000, acid value 15.7mgKOH/g solid content, OH value 38mgKOH/g solid content, heating residue 60%)
299 parts and in-house polyester resin B (Mn=4000, Mw
=60000, acid value 8mgKOH/g solid content, OH value 40mg
Pour 769 parts of KOH/g solid content, heating residue 60%). Then, a solution of 0.06 part of Denacol EX-411 (manufactured by Nagase Chemical Industries, Ltd.) and 0.01 part of Furmin DMC (manufactured by Kao Corporation) was added, and the temperature was heated to 130°C under a nitrogen atmosphere.
The addition reaction was completed by holding for 9 hours. Table 3 shows the characteristics of the resin C thus produced. Synthesis Example 2 Acid-added branched polyester resin A solution of 500 parts of branched polyester resin C synthesized by the method of Synthesis Example 1 and 4.2 parts of phthalic anhydride was placed in a reaction vessel equipped with a cooling tube, nitrogen introduction tube, thermometer, and stirring blade. Pour into a kolben and raise the temperature to 130℃. After the temperature was raised, the temperature was maintained at 130° C. for 1 hour to complete the addition reaction, and the mixture was cooled to obtain an acid addition branched polyester resin D. Table 3 shows the characteristics of resin D thus produced. Synthesis Example 3 Acid/Base Addition Branched Polyester Resin 500 parts of the acid addition branched resin D synthesized by the method of Synthesis Example 2, U-20SE60 (Mitsui (manufactured by Toatsusha)
Pour 21 parts into a Kolben, and the viscosity is 2 with a bubble viscometer.
The reaction was carried out at 110° C. until the reaction temperature exceeded the stage, and acid/base addition branched polyester resin E was obtained. Table 3 shows the characteristics of the resin E thus produced. Example 1 188 parts of toluene, 1062 parts of 12-hydroxystearic acid, and 2 parts of methanesulfonic acid were added to a reaction vessel equipped with a dehydrator, a cooling tube, a nitrogen introduction tube, a thermometer, and a stirring blade, and 2 parts of methanesulfonic acid were added at a reaction temperature of 148°C. The reaction was maintained for 30 minutes and the reaction was completed at an acid value of 46.5. The resulting resin was a brown viscous liquid. The resin is called MC. This resin was mixed with glycidyl group-containing polyfunctional epoxy compounds ELM120 (trifunctional epoxy compound manufactured by Sumitomo Chemical Co., Ltd.) and ELM434 (tetrafunctional epoxy compound manufactured by Sumitomo Chemical Co., Ltd.) in the proportions shown in Table 1. The addition reaction was carried out at a reaction temperature of 140°C for 7 hours. The properties obtained are shown in Table 2. Example 2 In order to confirm the compatibility of the in-house polyester resins A and B and the branched polyester resin C obtained in Synthesis Example 1, a 7 mil film was coated on a transparent glass plate with a well-mixed solution of each two types of resin. A resin film was prepared using an applicator (manufactured by Taiyu Kikai Co., Ltd.). and heated to 140℃ in a jet oven.
After drying for a period of time, the mixed resin film was evaluated when it was cooled to room temperature. The results are shown in Table 4. Example 3 Acid/base addition branched polyester resin Using the branched polyester resins C, D, and E obtained in Synthesis Examples 1, 2, and 3, glass was prepared using a paint sheaker (manufactured by Red Devil Co., Ltd.) according to the dispersion blending shown in Table 5. It was dispersed using beads as a medium. The 60° specular gloss of the obtained dispersion was measured using a Murakami gloss meter GM-26D model, and the paste viscosity was measured using a cone-plate viscometer (E-type viscometer, Tokyo Keiki Co., Ltd.). The results were obtained. From Table 5, the viscosity of the dispersion paste is reduced by using acid-added and acid/base-added resins,
It is observed that the 60° specular gloss is also improved and exhibits good viscosity.

【table】

[Table] Viscosity was compared using a Gardner viscosity tube. As shown in Table 2, by increasing the degree of branching, the viscosity did not change despite the increase in molecular weight.

【table】

【table】

【table】

Claims (1)

[Claims] 1 formula (In the formula, R is an n+m aliphatic, alicyclic, aromatic or cyclic hydrocarbon residue; X is an alkyd or polyester prepolymer chain; Y is a resin prepolymer chain other than acrylic resin; good;
A branched resin having a weight average molecular weight (measured by gel permeation chromatography, polystyrene equivalent) of 1000 to 200000 and a glass transition temperature of -20 to 100°C (n+m is a real number from 2 to 6). 2. The resin according to claim 1, wherein the alkyd or polyester prepolymer has a weight average molecular weight of 500 to 50,000 and a glass transition temperature of -20 to 100°C. 3 formulas (wherein R is an aliphatic, alicyclic, aromatic or heterocyclic hydrocarbon residue, n' is a real number from 2 to 6) and a polyfunctional epoxy compound represented by the formula X-COOH (wherein is an alkyd or polyester prepolymer having a carboxyl group (alkyd or polyester prepolymer chain) with a weight average molecular weight of 500 to 50,000 and a glass transition temperature of -20 to 100°C, and an acrylic having a carboxyl group represented by Y-COOH. Resin prepolymer chains other than resin (Y
may be a resin prepolymer chain other than acrylic resin and may be X. ) is characterized by the reaction of (In the formula, R, X and Y are each as described above; n+
m is a real number from 2 to 6). 4. The method according to claim 3, wherein the resin represented by Y-COOH is a polyester resin or an alkyd resin. 5. The method according to claim 3, wherein the polyfunctional epoxy compound is selected from neopentyl glycol diglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, and sorbitol polyglycidyl ether.