JPH0152425B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a coating composition with excellent pigment dispersibility. More specifically, double bond-containing addition reaction products,
The present invention relates to a novel resin composition obtained by further blending a crosslinking component with a copolymer obtained by polymerizing an oil-modified unsaturated alkyd and a copolymerizable polymerizable monomer. Conventionally, coating compositions that combine a vinyl copolymer and a crosslinking component have been developed. It has excellent performance in terms of yellowing, solvent resistance, and physical properties.
It is already widely used for finishing metal, aluminum sash, wood, plastic, slate, etc. However, due to its molecular structure, vinyl copolymers are generally less compatible with pigments than alkyd resins (hereinafter abbreviated as alkyd).
As a result, color separation during coating and pigment separation during storage occur, and therefore, from a practical standpoint, improvements in pigment dispersibility have been required. In order to improve the pigment dispersibility, for example, (a) an unsaturated dicarboxylic acid diester obtained by the reaction of an unsaturated dicarboxylic acid with a glycidyl ester of a tertiary aliphatic carboxylic acid, (b) an unsaturated oil Attempts have already been made to use copolymers with free alkyds and (c) polymerizable monomers.
(Japanese Patent Publication No. 53-766) To further explain this, the diester of unsaturated dicarboxylic acid as component (a) is It can be obtained as follows. In addition, as another method for improving the above-mentioned drawbacks, an oil- or fatty acid-containing unsaturated polyester,
It has also been proposed to use it in combination with an unsaturated trialkoxysilane monomer. (Japanese Unexamined Patent Publication No. 53-61694) However, even in a resin composition characterized by using an unsaturated dicarboxylic acid diester or an unsaturated trialkoxysilane monomer as described above, the coating film performance is sufficient for practical use. Pigment dispersibility could not be obtained. The present invention has been made to improve the drawbacks of the prior art as described above. That is, the present invention aims to provide a coating composition that has excellent pigment dispersibility and excellent coating film performance. That is, the present invention provides: A(a) obtained as a result of the reaction of (i) a glycidyl ester of a tertiary aliphatic carboxylic acid, (ii) an unsaturated polycarboxylic acid anhydride, and (iii) a hydroxyl group-containing saturated compound; Addition reaction product having one double bond in the molecule 5 to 95% by weight [However, the ratio of each of the above compounds is (i) epoxy group: (ii) acid anhydride group: (iii) hydroxyl Base =
0.8 to 1.2:1.0:0.8 to 1.2 (molar ratio)] (B) 95 to 5% by weight of oil-modified unsaturated alkyd, 5 to 45% by weight of a mixture consisting of B. Polymerizable monomer that can be copolymerized At least one type of 95
The present invention relates to a coating resin composition with excellent pigment dispersibility, which is obtained by further blending a crosslinking agent component into a copolymer obtained by reaction with ~55% by weight. One of the characteristics of the present invention is that 1
The purpose is to use an addition reaction product (a) containing double bonds. The reaction product (a) is synthesized by the following one-step reaction or two-step reaction. The production of the addition reaction product (a) containing one double bond in the molecule is carried out in an atmosphere of an inert gas such as carbon dioxide or nitrogen gas, or in an atmosphere of air if coloring is not a problem. Do it in an atmosphere. The reaction temperature is 180°C or lower. preferably 90
A range of ~135°C is suitable. In the case of synthesis by the one-step reaction, the progress of the reaction can be confirmed by measuring the acid value. However, in the present invention, the acid value is set to 40 or less, but 20
The following are appropriate. If the acid value exceeds 40, unreacted substances will remain and this will cause a decrease in the performance of the final coating film, which is not preferable. In addition, in the first step of the two-step reaction, the acid anhydride group of the acid anhydride

When [Formula] is reacted with a hydroxyl group-containing saturated compound, the reaction is carried out at 140°C or lower. That is, a ring-opening reaction of acid anhydride groups and an addition reaction (half-esterification) of hydroxyl groups are carried out under conditions in which the formation of water is not observed, thereby producing an esterified product containing a terminal carboxyl group. Then, in the second reaction, the esterified product is reacted with a glycidyl ester of a tertiary aliphatic carboxylic acid to obtain a double bond-containing addition reaction product. The end point of the first and second stage reactions can be determined by confirming the disappearance of the acid anhydride group in the first stage. However, since it is generally difficult to confirm by chemical analysis, it is desirable to use an infrared spectrophotometer. In the method using the infrared spectrophotometer, absorption due to acid anhydride groups appears sharply at around 1770 cm ^-1 and around 1850 cm ^-1 although it differs somewhat depending on the type of acid anhydride. Therefore, the progress of the first stage reaction can be determined by tracing these two absorptions, and can be quickly confirmed using this method. Next, the second stage reaction is carried out in the same temperature range as the first stage reaction. The end point of the reaction is when the acid value becomes 40 or less. Water may be produced in the one-stage or two-stage reaction. However, reactions under reaction conditions that produce water should be avoided in the present invention. This is because when water is produced, the acid anhydride and water react to open the acid anhydride group, thereby inhibiting the addition reaction of the hydroxyl group-containing saturated compound. The glycidyl ester of tertiary aliphatic carboxylic acid used to obtain the addition reaction product (a) containing one double bond in the molecule of the present invention includes:
Examples include compounds such as Cardiula E (trade name: Versatric acid glycidyl ester), neopentanoic acid glycidyl ester, neodecanoic acid glycidyl ester, neotridecanoic acid glycidyl ester, and the like. These may be used alone or as a mixture of two or more. Further, as the anhydride of unsaturated polyhydric carboxylic acid, any anhydride containing a double bond and an acid anhydride group in the molecule, such as maleic anhydride, can be used. Furthermore, as a hydroxyl group-containing saturated compound,
For example, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol, isobutyl alcohol, amyl alcohol, hexyl alcohol, 2-ethylbutyl alcohol, cyclohexanol, 2-ethylhexyl alcohol, benzyl alcohol, which has one hydroxyl group in the molecule. , propylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, and the like. In addition, part or all of the compound having one hydroxyl group in the molecule may be substituted with a polyvalent hydroxyl compound such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol,
It can also be substituted with 1,6-hexanediol, neopentyl glycol, trimethylolpropane, glycerin, etc. The hydroxyl group-containing saturated compounds can be used alone or in mixtures. In the reaction to obtain the addition reaction product (a) containing one double bond in the molecule in the present invention, both the one-step reaction and the two-step reaction can be carried out without a catalyst. The following reaction catalysts may be used as necessary. For example, secondary and tertiary amines or their inorganic or organic acid salts such as dimethylamine hydrochloride, triethylamine, benzyldimethylamine 2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl) Methyl)phenol, etc. Also, organic acid salts, such as metal salts of naphthenic acid, octylic acid, linoleic acid, such as sodium phthalate, zirconium naphthenate, chromium naphthenate, lithium naphthenate, zinc octylate, chromium linoleate, etc., may be mentioned. .
Also, Lewis acids and their organic adducts such as boron trifluoride, boron trifluoride monoethylamine, metal halides such as lithium chloride, lithium bromide, tin chloride, etc., or metal hydroxides such as sodium hydroxide. , lithium hydroxide, etc., hydrogen halides, such as hydrobromic acid, or alkyl titanates, such as butyl titanate. Furthermore, sulfonic acids and sulfonium salts such as para-toluenesulfonic acid, triphenylsulfonium chloride, etc., phosphonic acids and phosphonium salts such as benzenephosphonic acid, triphenylmethylphosphonium, iodide, etc., and quaternary ammonium salts. is trimethylbenzine ammonium chloride, etc. Also, imidazoles or their inorganic or organic adducts, such as 2-methyl-4-imidazole, 2-naphthyl-4,5-diphenylimidazole, and adducts such as 2-methyl Examples include a cyanoethylene type obtained by reacting imidazole with acrylonitrile, an adduct of 2-methylimidazole and trimellitic acid, and others such as triphenylphosphine and triphenylantimony. These may be used alone or in mixtures. When using such a reaction catalyst, the reactant 100
It is used in a range of about 0.01 to 10 parts by weight of catalyst. The optimum amount is preferably about 0.1 to 3.0 parts by weight. In the one-step reaction (i) in the present invention, an epoxy group of a glycidyl ester of a tertiary aliphatic carboxylic acid is attached in parallel to a carboxyl group generated by a ring-opening reaction between an acid anhydride and a hydroxyl group-containing saturated compound. Follow the process of reacting. Therefore, the ring-opening reaction of the acid anhydride group proceeds with a hydroxyl group-containing saturated compound and also with a secondary alcohol produced by the reaction between an epoxy group and a carboxyl group. Therefore, in the case of a one-step reaction, in order to completely open the ring of the acid anhydride group, the ratio of hydroxyl group to 1 mol of acid anhydride group is required to be 0.8 to 1.2 mol, preferably 0.9 to 1.1 mol. be. If the hydroxyl group is less than 0.8 moles,
There is a possibility that the acid anhydride group remains, which is not preferable because it may increase the viscosity of the system or deteriorate the performance of the final product during the reaction of the components (A) and (B). Also, when the amount of epoxy groups in the glycidyl ester of tertiary aliphatic carboxylic acid is less than 0.8 mole, the remaining carboxyl groups increase;
If the amount exceeds 1.2 moles, the glycidyl ester remains and the pigment dispersibility and the water resistance of the final coating film deteriorate, which is not preferable. In addition, when using a two-step reaction to obtain the addition reaction product (a), in order to improve the ring-opening reaction rate of the acid anhydride group, the amount of hydroxyl group is 1.0 mol or more per 1.0 mol of the acid anhydride group. It is preferable to use Next, the oil-modified unsaturated alkyd used in the present invention
(B) is obtained by a known esterification reaction from oil or its fatty acid, polyhydric alcohol, and polycarboxylic acid or its anhydride. The polyhydric alcohol and polycarboxylic acid are preferably combined so that the oil-modified unsaturated alkyd has a hydroxyl value of 50 to 200 (solid content). In order to copolymerize the oil-modified unsaturated alkyd with the double bond-containing addition reaction product and the polymerizable monomer to exhibit excellent performance, the oil-modified unsaturated alkyd may contain unsaturated dicarbonate in its raw material composition as necessary. acid from 0 to 10
It can be used in a range of % by weight. The dicarboxylic acid is preferably used when the double bond content in the oil or fatty acid is low, but may not be used when the double bond content is high. The reaction temperature during production of oil-modified unsaturated alkyd is 150
The temperature is raised to ~280°C, and the reaction is carried out while removing the water produced one by one. The end point of the reaction is determined by measuring the amount of water produced by the esterification reaction or the acid value. From the viewpoint of coating film performance, the acid value at the end of the reaction is preferably 50 or less. Examples of the oil or fatty acid used in the production of the oil-modified unsaturated alkyd include oils such as castor oil, cottonseed oil, dehydrated castor oil, linseed oil, safflower oil, soybean oil, tung oil, etc., or fatty acids thereof. . The amount of the oil or fatty acid used is preferably 5 to 70% by weight in the total formulation for producing the oil-modified unsaturated alkyd. In addition, examples of the polyhydric alcohol used in the production of the oil-modified unsaturated alkyd include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, butanediol 1,3, butanediol 1,4, and butanediol. Diol 2,3, Pentanediol 1,5, Hexanediol 1,6, Neopentyl glycol, 2,2,4-trimethylpentanediol-1,3, Hydrogenated bisphenol A, 2,2-di(4-hydroxy) propoxyphenyl) propane, glycerin, pentaerythritol diallyl ether, trimethylene glycol, 2-ethyl-1,3 hexanediol, trimethylolpropane, cyclohexanedimethanol-1,4,2,2,4-tetramethylcyclobutanediol- These include 1,3,1,4-bis(2-oxyethoxy)benzene, 2,2,4,4-tetramethylcyclobutanediol-1,3, and the like, and these may be used alone or as a mixture. Furthermore, saturated or unsaturated polycarboxylic acids or their acid anhydrides used in the production of oil-modified unsaturated alkyds include maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, maleic anhydride, and phthalic anhydride. , isophthalic acid, terephthalic acid, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, tetrabromophthalic anhydride, tetrachlorophthalic anhydride, hettic acid, 3,6-endomethylenetetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, Methylnadic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, anthracene-maleic anhydride adduct,
Examples include rosin-maleic anhydride adducts, which may be used alone or as a mixture. Although the reaction of the oil-modified unsaturated alkyd in the present invention can proceed without a catalyst, it is also possible to use a known reaction catalyst as necessary to shorten the industrial time. Examples include tetrabutyl zirconate, zirconium naphthenate, tetrabutyl titanate, tetraoctyl titanate, a mixture of stannous oxalate-sodium acetate, a mixture of stannous oxalate-sodium acetate-zinc acetate, and tetraphenyltin, and their use. The amount used is about 0.001 to 1.0 parts by weight based on 100 parts by weight of the total formulation. Furthermore, the copolymerizable polymerizable monomer used in the composition of the present invention includes a monomer having a functional group such as a hydroxyl group, a carboxyl group, an amino group, an epoxy group, or a monomer having a functional group. At least one type of monomer. The polymerizable monomer in the present invention has pigment dispersibility,
In terms of curing speed, degree of curing, etc., 0.3 to 35% by weight of a monoethylenically unsaturated monomer having a hydroxyl group, 0.1 to 5.0% by weight of a monoethylenically unsaturated monomer having a carboxyl group, and the remainder being other substances. of copolymerizable polymerizable monomers (total of 100
% by weight). Examples of the polymerizable monomer include styrene,
Methylstyrene, chlorstyrene, tertiarybutylstyrene, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, β-hydroxyethyl (meth)acrylate Acrylate, β-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, monoester of (meth)acrylic acid of glycerin trimethylolpropane, glycidyl (meth)acrylate,
N-butoxymethyl (meth)acrylamide,
N-tertiary butyl (meth)acrylamide, dimethylaminoethyl (meth)acrylate, diacetone acrylamide, vinylpyrrolidone, N-methylolacrylamide, acrylamide, (meth)acrylic acid, crotonic acid, vinyl acetate, (meth)acrylonitrile , ethylene glycol, mono(meth)acrylate, and derivatives thereof. In the present invention, the components (a) and (b) are 5 to 5.
It is necessary to use a proportion of 95/95 to 5% by weight, preferably 10 to 90/90/10% by weight. The limits of these weight ranges are determined from the viewpoint of pigment dispersibility. That is, 5% by weight of any component
If it does not meet the above criteria, the pigment dispersibility of the composition tends to decrease. Further, component (A) and component (B) are used in a ratio of 5 to 45/95 to 55% by weight, preferably 10 to 35/90 to 65% by weight. Component (A) is less than 5% by weight or 45% by weight
If it exceeds % by weight, the balance between compatibility with the crosslinking agent, gasoline resistance, water resistance, gloss, weather resistance, flexibility, hardness, etc. of the coating film, pigment dispersibility of the composition, painting workability, etc. will be affected. I don't like it because it will crumble. The copolymer obtained by copolymerizing components (A) and (B) in the present invention preferably has a hydroxyl value (solid content) in the range of 10 to 150. This range is preferable in terms of reactivity with the crosslinking agent and coating film performance. The hydroxyl value can be adjusted, for example, during the reaction of component (A), or by selection of raw materials for component (B), or (B).
This can be carried out appropriately by using a hydroxyl group-containing monomer in the components. A crosslinking agent is further added to the copolymer. As the crosslinking agent component used in the present invention, any compound that can react with the functional group in the copolymer, such as polyisocyanates, epoxy resins, and amino resins, can be used. Examples of the crosslinking agent components include Desmodyur N, Desmodyur L, Desmodyur 1L, Desmodyur HL (trade name, manufactured by Bayer), Takenate D-110N, Takenate D-202 (trade name, manufactured by Takeda Pharmaceutical Company Limited), Burnok D −750, Burnotsk
Polyisocyanates such as DN-950 [trade name manufactured by Dainippon Ink and Chemicals Co., Ltd.], or blocked isocyanates obtained by blocking these isocyanates with a known blocking agent; Epicoat
Epoxy resins such as 1001, Epicort 1004 (trade name manufactured by Ciel Corporation), Araldite 6071, Araldite 6084 (trade name manufactured by Ciba Corporation), Epiclon 1050, Epiclon 4050 [trade name manufactured by Dainippon Ink and Chemicals Co., Ltd.],
Other examples include alkoxylated melamine resins, alkoxylated urea resins, and alkoxylated guanamine resins. These crosslinking agent components can be used alone or as a mixture, and the amount used is customary depending on the type of copolymer, the curability of the composition, the performance of the final coating film, etc. Further, depending on the type of crosslinking agent component used, the resin composition can be a one-pack type or a two-pack type resin composition. The composition of the present invention thus obtained has a low viscosity,
In order to use component (a) with low hue,
A composition having a lower viscosity and a lower hue can be obtained compared to known compositions such as those disclosed in JP-A No. 766 and JP-A-53-61694. Therefore, it is very advantageous when a clear finish is required or when increasing the nonvolatile content of the copolymer. Furthermore, the coating composition of the present invention may contain known coloring pigments, extender pigments, dyes, various paint additives, modifiers, curing accelerators, reinforcing agents, etc., as necessary, within a range suitable for the application. Can be added. The coating resin composition of the present invention thus obtained can be applied by a known coating method such as brush, roller, dipping, or spray coating. The coating film after painting is formed at room temperature, by far infrared rays, or by baking and drying. In the case of baking drying, a temperature of 50 to 200°C for 10 to 60 minutes is appropriate. The coating resin composition of the present invention can be applied not only to all fields in which acrylic resin compositions have conventionally been used, but also to other coating fields. Therefore, it has great industrial value. The details of the present invention will be explained below with reference to Examples.
"Parts" or "%" are expressed as "parts by weight" or "% by weight." Synthesis Example 1 Synthesis of double bond-containing addition reaction product by one-step reaction Maleic anhydride was placed in two flasks equipped with a stirrer, condenser, thermometer, and nitrogen gas inlet.
362.8 parts (acid anhydride group ^-CO _-CO >0 3.7 mol), hexyl alcohol 389.4 parts (hydroxyl group 3.8 mol)
and 925 parts of Cardiura E (3.7 moles of epoxy group) were charged, and the reaction was carried out at 125 to 130°C for 3 hours in a nitrogen gas atmosphere to obtain a double bond-containing addition reaction product [A-
1] 167.72 copies were obtained. The color number of the reaction product is 1 or less, and the viscosity (20℃) is
It had a poise of 2.9 stokes, an acid value of 6.5, and a hydroxyl value of 125. Synthesis Example 2 Synthesis of double bond-containing addition reaction product by two-step reaction In the same flask as in Synthesis Example 1, in the first stage, 362.8 parts of maleic anhydride (3.7 mol of acid anhydride groups) and 389.4 parts of hexyl alcohol (hydroxyl group) were used. 3.8 moles)
After the reaction was carried out at 115 to 120℃ for 3 hours in a nitrogen gas atmosphere, an infrared spectrophotometer (hereinafter referred to as
When we measured the amount of acid anhydride groups remaining around 1770 cm ^-1 and 1850 cm ^-1 using lR, the reaction rate was 90.
It was %. Next, as a second-stage reaction, 925.0 parts of Cardiura E (3.7 moles of epoxy group) was added to the first-stage reactant.
A double bond-containing addition reaction product [A-2] 1677.2 was obtained by conducting the reaction at 125 to 130°C for 3 hours in a nitrogen atmosphere.
I got the department. The color number of the reaction product is 1 or less, and the viscosity (20℃) is
It had a poise of 2.9 stokes, an acid value of 4.0, and a hydroxyl value of 125. Synthesis Example 3 Synthesis of fatty acid-modified unsaturated alkyd In a flask using a partial condenser instead of the condenser in Synthesis Example 1, 110.4 parts of coconut oil fatty acid, 5.2 parts of neopentyl glycol,
357.7 parts of 1,6-hexanediol, 177.5 parts of trimethylolpropane, and 601.5 parts of isophthalic acid were charged and heated at 190°C for 2 hours under a nitrogen gas atmosphere.
When the reaction was carried out at 200℃ for 3 hours, the acid value was 28.5.
An esterified product of was obtained. As a second stage reaction, 54.6 parts of fumaric acid (4.2% in the raw material composition) was added to the esterified product and the mixture was further heated to 210°C.
The reaction was carried out for 5 hours to obtain a fatty acid-modified unsaturated alkyd with an acid value of 11.0 and a hydroxyl value of 132.
Next, xylol/triol = 60/40 (weight ratio)
Dilute to 60% non-volatile content using a mixed solvent of
6.6 and a hydroxyl value of 79, a fatty acid-modified unsaturated alkyd solution [B-1] was obtained. Synthesis Example 4 Synthesis of oil-modified unsaturated alkyd In a flask using a water separator instead of the condenser of Synthesis Example 1, 436.0 parts of coconut oil, 201.2 parts of trimethylolpropane, and 0.57 parts of sodium formate were charged in the first stage under a nitrogen gas atmosphere. The transesterification was completed by heating at 260°C for 1.5 hours. Then 130
Cool to ℃, 70.3 parts of neopentyl glycol,
89.4 parts of trimethylolpropane, phthalic anhydride
417.6 parts of fumaric acid, 40.0 parts of fumaric acid, and 50.6 parts of xylol were added, and the reaction was carried out at 200°C for 6 hours and then at 220°C for 2 hours to obtain an esterified product having an acid value of 10.8 and a hydroxyl value of 60. The obtained esterified product was diluted with toluene to a non-volatile content of 60%, and the viscosity (20℃) was 2.3.
Stokes poison, acid number 6.5, hydroxyl number 36
An oil-modified unsaturated alkyd solution [B-2] was obtained. Example 1 68.0 parts of toluene and 127.5 parts of isobutyl acetate were charged into a flask 1 equipped with a stirrer, a condenser, a thermometer, and a dropping device, and after raising the temperature to 110°C, the double bond-containing addition reaction product [A -1〕
or [A-2] 51.0 parts, fatty acid-modified unsaturated alkyd obtained in Synthesis Example 3 [B-1] 204.0 parts, styrene 34.0 parts, methyl methacrylate 68.0 parts, vinyltoluene 17.0 parts, β-hydroxyethyl acrylate 85.0 parts , 59.5 parts of toluene, and 12.0 parts of benzoyl peroxide were dropped into the flask over a period of 3 hours to carry out the polymerization reaction, and after the addition, the reaction was continued for an additional 5 hours. The obtained copolymer solution [C-1] had a viscosity (at 20° C.) of 4.5 Stokes, an acid value of 6.6, and a hydroxyl value of 88. Example 2 Triol was added to one flask similar to Example 1.
After charging 150.0 parts and raising the temperature to 110°C, the double bond-containing addition reaction product [A-1] or [A-
2] 60.0 parts, oil-modified unsaturated alkyd obtained in Synthesis Example 4 [B-2] 180.0 parts, styrene 50.0 parts, methyl methacrylate 90.0 parts, ethyl acrylate 40.0 parts
parts, 30.0 parts of β-hydroxyethyl acrylate,
A mixture consisting of 0.9 parts of methacrylic acid, 156.9 parts of toluene, and 7.0 parts of benzoyl peroxide was added dropwise into the flask over 3 hours, and the reaction was continued for an additional 5.5 hours after the addition was completed. The obtained copolymer solution [C-2] had a viscosity (20°C) of 2.8 Stokes,
The acid value was 5.1 and the hydroxyl value was 38. Comparative Example 1 Xylol 119.0 in the same flask as Example 1
After charging 175.0 parts of butyl acetate and raising the temperature to 100°C, 140.0 parts of styrene, 81.2 parts of β-hydroxylethyl methacrylate, and butyl acrylate were added.
A mixture consisting of 98.0 parts of methyl methacrylate, 23.8 parts of methyl methacrylate, 7.0 parts of methacrylic acid, 0.7 parts of benzoyl peroxide, and 21.0 parts of xylol was added dropwise into the flask over 3 hours. After the dropwise addition was completed, the polymerization reaction was further carried out at 100℃ for 6 hours, and the xylol was cooled.
It was diluted by adding 35.0 parts. The obtained copolymer solution [D-1] had a viscosity (20°C) of 5.1 Stokes, an acid value of 6.1, a hydroxyl value of 50, and a non-volatile content.
It was 51.5%. 97.0 parts of the copolymer solutions obtained in Examples 1 and 2 and Comparative Example 1 and 3.0 parts of carbon black were mixed and kneaded using three rollers, and the pigment dispersibility after kneading was compared twice and five times. and display the results.
Shown in 1.

[Table] Example 3 Copolymer solution obtained in Example 1 [C-1] 70
30 parts of titanium oxide was mixed with the mixture and dispersed by roller kneading to obtain a paint. Example 4 Copolymer solution obtained in Example 1 [C-1]
A coating material was obtained by dispersing 30.0 parts of titanium oxide and 20.0 parts of butylated melamine resin (trade name: Super Betsucomin J-820, manufactured by Dainippon Ink & Chemicals Co., Ltd.) into 50.0 parts by roller kneading. Example 5 50.0 parts of the above copolymer solution [C-1], epoxy resin solution (70% of Ciel Co., Ltd. trade name Epicote 1001)
A coating material was obtained by dispersing 2.0 parts of xylol solution, 18.0 parts of butylated melamine resin (same as in Example 5), and 30.0 parts of titanium oxide by roller kneading. Example 6 Using the copolymer solution [C-2] obtained in Example 2, a paint was obtained in the same manner as in Example 3. Example 7 Using the copolymer solution [C-2] obtained in Example 2, a paint was obtained in the same manner as in Example 4. Example 8 A coating material was obtained in the same manner as in Example 5 using the copolymer solution [C-2]. Example 9 A black pigment (trade name: Laben 14, manufactured by Columbia Carbon) was added to 94.0 parts of the copolymer solution [C-1].
6.0 parts were added and kneaded with a roller to obtain a paint. Example 10 7.0 parts of an orange pigment (trade name: Hostabam Orange GR manufactured by Hoechst) was added to 93.0 parts of the copolymer solution [C-1] and kneaded with a roller to obtain a paint. Example 11 A paint was obtained in the same manner as in Example 9 using the copolymer solution [C-2]. Example 12 Example 10 using the copolymer solution [C-2]
Paint was obtained in the same manner. Comparative Example 2 A coating material was obtained in the same manner as in Example 3 using the copolymer solution [D-1]. Comparative Example 3 A coating material was obtained in the same manner as in Example 4 using the copolymer solution [D-1]. Comparative Example 4 A coating material was obtained in the same manner as in Example 5 using the copolymer solution [D-1]. Comparative Example 5 A coating material was obtained in the same manner as in Example 9 using the copolymer solution [D-1]. Comparative Example 6 Example using the copolymer solution [D-1]
A paint was obtained in the same manner as in 10. The pigment dispersibility of the paints obtained in Examples 3, 6, 9, 10, 11, and 12 and Comparative Examples 2, 5, and 6 was measured, and the results are shown in Table 2. The above pigment dispersibility is paint (white) / paint (black) =
Immediately before use, mix well at a mixing ratio of 9/1 (weight ratio) or paint (white) and paint (orange) = 9/1 (weight ratio), and add polyisocyanate as a crosslinking agent [Bayer's product name Desmodyur N- 75: Biuret structure of hexamethylene diisocyanate] was added at an equivalent ratio of OH/NCO = 1.0, and after stirring,
Toluol/isobutyl acetate = 60/40 (weight ratio)
The viscosity of the composition (Food Cup #4) was adjusted to about 20 seconds using mixed thinner, and then sprayed and flow coated onto a tin plate, dried at room temperature, and measured for the color difference (△E) of the paint film. It was determined by

[Table] Note 1: Paint film obtained by spray painting and
Color difference in paint film obtained by flow coating.
It is clear from Table 2 that the paint mixtures obtained in the Examples of the present invention (Samples Nos. 1 to 4) had very good pigment dispersibility (△E), but the comparative samples The pigment dispersibility was extremely poor. Next, the coating film performance obtained in Examples 3 to 8 and Comparative Examples 2 to 4 was evaluated, and the results are shown in Table 3.

【table】

[Table] From the results shown in Table 3 above, it is clear that the coating resin composition of the present invention has significantly improved pigment dispersibility as compared to the comparative example composition, and also has extremely excellent coating film performance. Ta.

Claims (1)

[Scope of Claims] 1 A(a)(i) glycidyl ester of tertiary aliphatic carboxylic acid, (ii) unsaturated polyhydric carboxylic acid anhydride, and (iii) obtained as a result of the reaction of a hydroxyl group-containing saturated compound Addition reaction product having one double bond in the molecule 5 to 95% by weight [However, the ratio of each compound is (i) epoxy group: (ii)
Acid anhydride group: (iii) hydroxy group = 0.8 ~
1.2:1.0:0.8 to 1.2 (molar ratio)] (B) 95 to 5% by weight of oil-modified unsaturated alkyd, 5 to 45% by weight of a mixture consisting of B: a small amount of copolymerizable polymerizable monomers Tomo 1 type
A coating resin composition with excellent pigment dispersibility, which is obtained by further blending a crosslinking agent component with a copolymer obtained by reaction with 95 to 55% by weight.