JP2001139892A - Resin composition for coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for a coating material which is excellent in coating material stability and in gloss and adhesivity enables hardness to be highly compatible with processibility and stain resistance, and has an excellent weatherability unobtainable by prior arts. SOLUTION: This resin composition contains (A) an organic resin having ionic groups and (B) inorganic fine particles having an average particle size of 5-200 nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paint resin composition having excellent storage stability of paint, high stain resistance and weather resistance, excellent hardness and gloss, and excellent workability. It is about things.

[0002]

2. Description of the Related Art At present, acrylic resins, polyester resins, polyurethane resins, epoxy resins, vinyl chloride resins and the like are used as coating resins. In these resin systems, blending of inorganic fine particles represented by colloidal silica has been studied in order to improve the hardness, stain resistance, weather resistance, corrosion resistance and the like of the coating film. However, these inorganic fine particle-containing paints are unstable, have poor paint stability, and have problems of poor processability.

Various studies have been made to solve these problems. For example, Japanese Patent Application Laid-Open No. 7-178335 proposes composite fine particles in which an organic resin is integrated with inorganic fine particles. When the composite fine particles are blended with a film-forming resin composed of an acrylic polyol and an isocyanate compound instead of the conventional reinforcing inorganic filler such as colloidal silica, the organic resin integrated with the inorganic fine particles has an affinity for the film-forming resin. Because of this property, the dispersion stability (paint stability) of the inorganic fine particles in the film-forming resin can be improved, and the obtained coating film has excellent weather resistance and contamination resistance. However, this has a problem that the coating film is brittle and the workability is remarkably inferior, and the adhesion is also insufficient, so that the use thereof is limited.

[0004] Also, Japanese Patent Application Laid-Open No. 11-148022,
JP-A-11-148022 proposes a curable composition and a coating agent which react with a polymer having a functional group, an organosilylated silicic acid polymer and a functional group having a functional group. The obtained film has excellent weather resistance and stain resistance, but has poor paint stability and poor workability.

[0005] For the purpose of improving corrosion resistance, a polyester resin blended with colloidal silica is CN9.
6-0118 is known. Here, it is disclosed that colloidal silica is added at the time of polyester polymerization in order to impart paint stability. However, paint stability is insufficient, and the amount of colloidal silica is limited to a very small amount. Also, the weather resistance is insufficient.

[0006]

As described above, the coating stability of the coating composition containing inorganic fine particles is improved, and excellent workability is imparted. Further, stain resistance and weather resistance are high, and excellent hardness and gloss are obtained. It has been a long-standing problem to provide a resin composition for coatings having both of the above.

[0007]

Means for Solving the Problems The present inventors have intensively studied to solve the above-mentioned problems, and have high stain resistance and weather resistance, excellent hardness and gloss, and excellent workability. The present invention was completed as a result of repeated experiments and studies in order to provide a coating resin composition having both good paint stability.

[0008] That is, the present invention is a resin composition for a coating, comprising an organic resin (A) containing an ionic group and inorganic fine particles (B) having an average particle diameter of 5 to 200 nm.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the organic resin (A) containing an ionic group used in the present invention, the ionic group includes:
Sulfonate groups, sulfate groups, carboxylate groups and the like can be mentioned. These ionic groups are prepared by copolymerizing a dicarboxylic acid or glycol containing an ionic group such as a sulfonic acid group with a polyester resin, or by synthesizing a urethane-modified resin using a glycol containing a sulfonic acid group as a chain extender. A known method is used in which a carboxyl group-containing glycol is used as a chain extender, introduced into a urethane-modified resin, and then neutralized with an alkali. As the ionic group, a metal sulfonate and a phosphonium sulfonate are preferred.

Surprisingly, by introducing an ionic group into the organic resin, the coating stability when the inorganic fine particles (B) are blended is remarkably improved. In addition, when the organic resin (A) of the present invention is used in combination with the other components, the feature of improving the compatibility is exhibited. In the case of a sulfonate group, the content of the ionic group is preferably 0.01 to 5.0% by weight, more preferably 0.03 to 3.0% by weight as the sulfur content in the organic resin (A) of the present invention. 5% by weight, most preferably 0.05% to 2.5% by weight. 0.01% by weight
If it is less than 5, good paint stability and compatibility with other resins may not be obtained, and if it exceeds 5% by weight, water resistance may decrease.

The compounds used for the introduction of the polar groups include dicarboxylic acids or glycols containing sulfonic acid groups, such as 5-sulfoisophthalic acid, sulfoterephthalic acid, and 4-sulfonaphthalene-2,7-dicarboxylic acid. Acid, metal salt such as 5 [4-sulfophenoxy] isophthalic acid or 2-sulfo-1,4-butanediol, 2,5
Metal salts such as -dimethyl-3-sulfo-2,5-hexanediol. Examples of the phosphonium salt of a sulfonic acid group-containing aromatic dicarboxylic acid or a sulfonic acid group-containing glycol include those represented by the following general formula.

[0012]

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(Where A is an aromatic group, X 1 and X 2 are ester-forming functional groups, R 1, R 2, R 3 and R 4 are alkyl groups, at least one of which is an alkyl group having 6 to 20 carbon atoms)

Specifically, tri-n-sulfoisophthalic acid
-Butyldecylphosphonium salt, tri-n-butyloctadecylphosphonium sulfoisophthalate, tri-n-butylhexadecylphosphonium sulfoisophthalate, tri-n-butyltetradecylphosphonium sulfoisophthalate, tri-n sulfoisophthalate -Butyl dodecyl phosphonium salt, tri-n-sulfoterephthalate
-Butyldecylphosphonium salt, tri-n-butyloctadecylphosphonium sulfoterephthalate, tri-n-butylhexadecylphosphonium sulfoterephthalate, tri-n-butyltetradecylphosphonium sulfoterephthalate, tri-n sulfoterephthalate -Butyl dodecyl phosphonium salt, 4-sulfonaphthalene-2,
7-dicarboxylic acid tri-n-butyldecylphosphonium salt, 4-sulfonaphthalene-2,7-dicarboxylic acid tri-n-butyloctadecylphosphonium salt, 4-sulfonaphthalene-2,7-dicarboxylic acid tri-n-butylhexa Decylphosphonium salt, 4-sulfonaphthalene-
And 2,7-dicarboxylic acid tri-n-butyltetradecylphosphonium salt, 4-sulfonaphthalene-2,7-dicarboxylic acid tri-n-butyldodecylphosphonium salt, and the like. As the carboxyl group-containing glycol,
Dimethylolpropionic acid, dimethylolbutanoic acid and the like. These can be introduced into an organic resin and then neutralized with ammonia or the like before use.

The organic resin containing an ionic group of the present invention (A)
The resin skeleton is made of polyester resin, modified polyester resin, vinyl chloride copolymer resin, (meth) acrylic resin,
Epoxy resins and the like can be mentioned. Among them, a polyester resin and / or a modified polyester resin are preferable in terms of processability and adhesion, and a polyester resin is more preferable in terms of weather resistance. Examples of the method for modifying the polyester resin include urethane modification, epoxy modification, acrylic modification, and silicon modification. As a method for introducing an ionic group, it is preferable to directly copolymerize the above-mentioned sulfonic acid group-containing compound with a polyester resin, and to synthesize a polyester polyol into which a sulfonic acid group is introduced by the same method and then modify the urethane with an isocyanate compound. Modified polyesters are also preferred. Further, a method for introducing an ionic group containing sulfur or phosphorus into the vinyl chloride resin can be introduced by a known method as shown in Japanese Patent Publication No. 1-262525.

The dicarboxylic acids copolymerized with the polyester resin and the modified polyester resin include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, and 2,6-naphthalenedicarboxylic acid, succinic acid, glutaric acid, and adipic acid. , Sebacic acid, dodecane dicarboxylic acid, aliphatic dicarboxylic acids such as azelaic acid,
Examples include alicyclic dicarboxylic acids such as 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid. In addition, a polyvalent carboxylic acid such as trimellitic anhydride or pyromellitic anhydride may be used in combination as long as the content of the invention is not impaired.

Among them, aromatic dicarboxylic acids include
Terephthalic acid, isophthalic acid, and orthophthalic acid are preferable, and it is particularly preferable to use isophthalic acid and orthophthalic acid in combination from the viewpoint of weather resistance. As the aliphatic dicarboxylic acid, adipic acid and sebacic acid are preferred. As the alicyclic dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid is preferable. When a high degree of weather resistance is required, the content of the aromatic dicarboxylic acid in the acid component is preferably 70 mol% or less,
More preferably 50 mol% or less, further preferably 30 mol% or less.
Mol% or less. When the amount of the aromatic dicarboxylic acid decreases, the physical properties of the coating film deteriorate. Therefore, it is preferable to use an alicyclic dicarboxylic acid in combination.

The glycol components copolymerized with the polyester resin and the modified polyester resin include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol and neopentyl. Glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol,
2-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,9-nonanediol, 1,10- Alkylene glycols such as decanediol, 1,4-cyclohexanedimethanol, 1,3
-Cyclohexanedimethanol, 1,2-cyclohexanedimethanol, hydrogenated bisphenol A, hydrogenated bisphenol F, alicyclic glycols such as TCD glycol, dimer diol, and the like. Of these, particularly preferred from the viewpoint of coating film properties and weather resistance are 1,
6-hexanediol, 1,5-pentaneddiol, neopentyl glycol, 3-methyl-1,5-pentanediol. Further, within a range not to impair the content of the invention, trimethylolethane, trimethylolpropane,
Polyhydric polyols such as glycerin and pentaerythritol may be used in combination.

After the above polyester resin is polymerized, trimellitic anhydride, phthalic anhydride, pyromellitic anhydride, succinic anhydride, 1,8-naphthalic anhydride, 1,2-cyclohexanedicarboxylic anhydride, etc. are post-added. To give an acid value. By imparting an acid value, stain resistance can be further improved. Preferred acid values are 300 equivalents / 10 ⁶ g or less, more preferably less than 600 equivalents / 10 ⁶ g. Acid value is 600 equivalent / 10 ⁶ g
If it exceeds, good workability may not be obtained.

The organic resin containing an ionic group of the present invention (A)
Has a reduced viscosity of 0.2 dl / g or more, preferably 0.4 d / g or more.
1 / g or more. If the reduced viscosity is less than 0.2 dl / g, good processability may not be obtained. The number average molecular weight is preferably 3,000 or more, more preferably 7,000 or more, and most preferably 10,000 or more.

The organic resin containing an ionic group of the present invention (A)
Can be blended with another organic resin having no ionic group and capable of forming a coating film. For other resins, molecular weight, shape, composition, the presence or absence of functional groups, etc.,
There is no particular limitation, and any organic resin can be used. The structure of the organic resin may be any shape such as a linear, branched or crosslinked structure. The number average molecular weight of the other organic resin is preferably from 1,000 to 500,000, more preferably from 2,000 to 100,000. In the case of an aqueous dispersion (emulsion), it may have a higher molecular weight.

Specific examples of other organic resins include, for example, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, ethyl methacrylate , N-propyl methacrylate,
Isopropyl methacrylate, n-butyl methacrylate,
(Meth) such as tert-butyl methacrylate, 2-ethylhexyl methacrylate, and diglycidyl methacrylate
Acrylic esters, acrylic acid, methacrylic acid, styrene, vinyltoluene, 1-methylstyrene, vinyl acetate, vinyl chloride, vinylidene chloride, acrylonitrile, vinyl acetate, vinyl propionate, vinyl stearate, allyl acetate, diallyl adipate, Diallyl itaconate, diethyl maleate, acrylamide, N-
A homo- or copolymer of at least one or more ethylenically unsaturated monomers selected from methylol acrylamide, N-butoxymethyl acrylamide, diacetone acrylamide, ethylene, propylene, isoprene, etc .; polyolefins such as polyethylene and polypropylene; polychlorination Vinyl, polyvinylidene chloride, polyester resin, modified polyester resin, and the like.

These resins include amino groups, epoxy groups,
A functional group such as a hydroxyl group or a carboxyl group may be contained or modified. Among them, from the viewpoint of weather resistance, (meth) acrylate resin, (meth) acrylate-
It is possible to use an organic resin containing a (meth) acrylate unit such as a styrene resin or a (meth) acrylate-polyester graft resin in combination with the organic resin (A) containing an ionic group of the present invention. Particularly preferred. Further, from the viewpoint of weather resistance, it is particularly preferable to introduce a structure such as benzophenone, hindered amine or benzotriazole into the other organic resin containing these (meth) acrylate units by copolymerization. These introduction methods can be introduced by a known method such as the method described in Japanese Patent Laid-Open Publication No. H8-3133.

The organic resin containing these (meth) acrylate units preferably contains a hydroxyl group from the viewpoint of paint stability. The preferred content is a hydroxyl value,
5 to 300 mgKOH / g, more preferably 10 to 20 mgKOH / g
0 mgKOH / g. The hydroxyl group can be introduced into the (meth) acrylate resin by copolymerizing a hydroxyl group-containing unsaturated monomer. Examples of the hydroxyl group-containing unsaturated monomer include 2-hydroxyethyl acrylate and 2-acrylic acid.
Hydroxyl-containing unsaturated monomers such as hydroxypropyl, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, allyl alcohol, homoallyl alcohol, cinnamon alcohol, and crotonyl alcohol;
(B) For example, ethylene glycol, ethylene oxide, propylene glycol, propylene oxide,
A dihydric alcohol or epoxy compound such as butylene glycol, butylene oxide, 1,4-bis (hydroxymethyl) cyclohexane, phenyl glycidyl ether, glycidyl decanoate, and Praxel FM-1 (manufactured by Daicel Chemical Industries, Ltd.); Examples include a hydroxyl group-containing unsaturated monomer obtained by a reaction with an unsaturated carboxylic acid such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, and itaconic acid. At least one selected from these hydroxyl group-containing unsaturated monomers can be polymerized to produce a hydroxyl group-containing organic resin.

As another organic resin, a polyester resin containing no ionic group can be used in combination. They are,
Substantially corresponds to the above-mentioned ionic group-containing polyester resin (A) obtained by removing ionic groups.

The average particle size used in the present invention is from 5 to 20.
The inorganic fine particles (C) having a thickness of 0 nm may be fine particles substantially composed of an inorganic substance, regardless of the types of constituent elements, but inorganic oxides are preferably used. The shape of the inorganic fine particles is arbitrary, such as a spherical shape, a needle shape, a plate shape, a scale shape, a crushed granule shape, and a grape tuft shape. The average particle size of the inorganic fine particles is 5
２００200 nm, preferably 5-100 nm. When the average particle diameter of the inorganic fine particles is less than 5 nm, the surface energy of the inorganic fine particles increases, and the inorganic fine particles are easily aggregated. The average particle diameter of the inorganic fine particles is 20
If the thickness exceeds 0 nm, the stability of the paint will be deteriorated, and the transparency and gloss of the film will be reduced.

The concentration of the inorganic fine particles of the present invention is not particularly limited.
%, More preferably 1 to 50% by weight. When the concentration of the inorganic fine particles is high, the viscosity of the dispersion becomes high, and it becomes difficult to use the dispersion for various purposes.

The inorganic oxide is defined as various oxygen-containing metal compounds in which a metal element forms a three-dimensional network mainly through a bond with an oxygen atom. Examples of the metal element constituting the inorganic oxide include, for example, Periodic Tables II to VI of the Elements.
An element selected from the group III is preferable, and an element selected from the group III to V is more preferable. Among them, Si, Al, T
An element selected from i and Zr is particularly preferred. Silica fine particles in which the metal element is Si are the most preferable inorganic fine particles because they are easy to produce and easily available. Among the inorganic fine particles, the inorganic oxide contains, in its structure, at least one selected from, for example, an organic group such as an alkyl group having 20 or less carbon atoms, a cycloalkyl group, an aryl group, and an aralkyl group, and a hydroxyl group. Sometimes.

These groups may contain various groups derived from the hydrolyzable metal compound as a raw material. These are hydrolyzed and further condensed to give 3
A network can be formed dimensionally. Examples of such a hydrolyzable metal compound include metal halides, metal nitrates, metal sulfates, metal ammonium salts, organic metal compounds, alkoxy metal compounds, and derivatives of these metal compounds. Only the species or a mixture of two or more species can be used.

As the metal compound which can be hydrolyzed, the metal element constituting the metal compound is represented by III in the Periodic Table of the Elements.
It is preferable to use at least one metal element selected from the group consisting of Group IV, IV, and V elements. Above all, a metal compound in which the metal element constituting the metal compound is at least one metal element selected from the group consisting of Si, Al, Ti and Zr is more preferable.

The inorganic fine particles can contain an alkoxy group. The content of the alkoxy group is preferably 0.01 to 50 mmol per 1 g of the composite fine particles. The alkoxy group indicates a group bonded to a metal element constituting the skeleton of the inorganic fine particles, and indicates an Ra-O group. Here, Ra is an alkyl group which may be substituted for the metal element, and Ra-
When there are a plurality of O groups, the Ra-O groups may be the same or different. Specific examples of Ra include methyl,
Ethyl, n-propyl, isopropyl, n-butyl and the like can be mentioned. The alkoxy group complementarily improves the affinity of the inorganic fine particles with the organic medium and the dispersibility in the organic medium. These inorganic fine particles are described in, for example,
It can be prepared by a known method such as 0-324845. The inorganic oxide constituting the inorganic fine particles need not be only one kind, but may be two or more kinds.

The inorganic fine particles (B) of the present invention are particularly preferably organic-inorganic composite fine particles in which an organic resin is fixed on the surface of the inorganic fine particles from the viewpoint of paint stability.

The organic-inorganic composite fine particles in the present invention are composite fine particles in which an organic resin is fixed on the surface of the inorganic fine particles. Here, fixing does not mean mere adhesion and adhesion, It means that the organic resin is not detected in the washing liquid obtained by washing the inorganic composite fine particles with an arbitrary solvent, which strongly suggests that a chemical bond is generated between the organic resin and the inorganic fine particles. Is what it is.

The organic-inorganic composite fine particles may contain an organic resin in the fine particles. This makes it possible to impart appropriate softness and toughness to the inorganic substance as the core of the organic-inorganic composite fine particles. The presence or absence of the organic resin in the organic-inorganic composite fine particles is determined by, for example,
It can be confirmed by comparing the measured value of the specific surface area of the fine particles after heating at 0 to 700 ° C. and thermally decomposing the organic resin with the theoretical value of the specific surface area calculated from the diameter of the fine particles. That is, when the organic resin is included in the organic-inorganic composite fine particles, the organic resin is thermally decomposed by heating, and a large number of pores are generated in the fine particles. Is much larger than the theoretical value of the specific surface area calculated from the diameter of the fine particles.

The average particle diameter of the organic-inorganic composite fine particles is 5 to 2
00 nm, preferably 5 to 100 nm. When the average particle diameter of the organic-inorganic composite fine particles is less than 5 nm, the surface energy of the organic-inorganic composite fine particles increases, so that aggregation or the like is likely to occur. On the other hand, when the average particle diameter of the organic-inorganic composite fine particles exceeds 200 nm, physical properties such as transparency of the coating film are deteriorated when used in a paint or the like. These organic-inorganic composite fine particles are described, for example, in Japanese Patent Laid-Open Publication No. Hei 7-1783.
It can be prepared by a known method such as Japanese Patent Publication No. 35.

The dispersion medium of the organic-inorganic composite fine particles of the present invention is not particularly limited in the composition and the like, but is preferably an organic solvent or water in which the organic chains in the organic-inorganic composite fine particles are dissolved. Among the organic solvents described in the above production method, at least one organic solvent selected from the group consisting of esters, alcohols, ketones, and aromatic hydrocarbons and / or dispersion of organic-inorganic composite fine particles dispersed in water. Since the body has good storage stability for a long period of time and good dispersion stability in various organic media, it can be used for various applications.

The organic resin constituting the organic-inorganic composite fine particles used in the coating resin composition of the present invention is not particularly limited, but specific examples thereof include ethyl acrylate, n-propyl acrylate, isopropyl acrylate, and the like. N-butyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, (Meth) acrylic esters such as diglycidyl methacrylate, acrylic acid, methacrylic acid, styrene, vinyltoluene, 1-methylstyrene, vinyl acetate, vinyl chloride, vinylidene chloride, acrylonitrile, vinyl acetate, vinyl propionate, vinyl stearate , Allyl acetate, diallyl adipate, diallyl itaconate, diethyl maleate, acrylamide, N-methylol acrylamide, N-butoxymethyl acrylamide, diacetone acrylamide, at least one ethylene selected from ethylene, propylene, isoprene and the like. Homo- or copolymers of unsaturated monomers, polyolefins such as polyethylene and polypropylene, polyvinyl chloride, polyvinylidene chloride, polyester resins, and modified polyester resins.

Of these, (meth) acrylic resins, (meth) acryl-styrene resins, and (meth) acryl-polyester resins having film forming ability are preferred.

These resins have amino groups, epoxy groups,
A functional group such as a hydroxyl group or a carboxyl group may be contained or modified. Among them, from the viewpoint of weather resistance, (meth) acrylate resin, (meth) acrylate-
It is possible to use an organic resin containing a (meth) acrylate unit such as a styrene resin or a (meth) acrylate-polyester graft resin in combination with the organic resin (A) containing an ionic group of the present invention. Particularly preferred.

The organic resin containing a (meth) acrylate unit used for compounding the inorganic composite fine particles preferably contains a hydroxyl group from the viewpoint of paint stability.
The preferred content is 5 to 300 mg KO as a hydroxyl value.
H / g, more preferably 10 to 200 mgKOH / g. The hydroxyl group can be introduced into the (meth) acrylate resin by copolymerizing a hydroxyl group-containing unsaturated monomer. As the hydroxyl group-containing unsaturated monomer, for example, acrylic acid 2-
Hydroxy group-containing unsaturated monomers such as hydroxyethyl, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, allyl alcohol, homoallyl alcohol, cinnamon alcohol, crotonyl alcohol, ethylene glycol,
Ethylene oxide, propylene glycol, propylene oxide, butylene glycol, butylene oxide, 1,4-bis (hydroxymethyl) cyclohexane, phenylglycidyl ether, glycidyl decanoate, Praxel FM-1 (manufactured by Daicel Chemical Industries, Ltd.) And a hydroxyl group-containing unsaturated monomer obtained by reacting a polyhydric alcohol or an epoxy compound with an unsaturated carboxylic acid such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, and itaconic acid. it can. At least one selected from these hydroxyl group-containing unsaturated monomers can be polymerized to produce a hydroxyl group-containing organic resin.

The resin composition for coatings of the present invention shows satisfactory performance even when used alone, but the coating film properties are further improved by using a curing agent capable of reacting with the organic resin and / or inorganic fine particles contained therein. Can be. Examples of the curing agent include an alkyl etherified amino formaldehyde resin, an epoxy compound and an isocyanate compound.
Among them, alkyl etherified aminoformaldehyde resin and / or isocyanate compound are preferable from the viewpoint of processability and weather resistance.

Alkyl etherified aminoformaldehyde resins include, for example, formaldehyde or paraformaldehyde alkyletherified with an alcohol having 1 to 4 carbon atoms such as methanol, ethanol, n-propanol, isopropanol, n-butanol and urea. Condensation products with N, N-ethylene urea, dicyandiamide, aminotriazine and the like; Butoxylated methylol melamine, mixed methoxylated / butoxylated methylol melamine, butoxylated methylol benzoguanamine, and the like. It preferred from the viewpoint of workability, methoxylated methylolmelamine, butoxy methylol melamine or methoxylated / butoxylated mixed melamine, may be used alone, or in combination.

As the isocyanate compound, there are aromatic and aliphatic diisocyanates and trivalent or higher polyisocyanates, and either low molecular weight compounds or high molecular weight compounds may be used. For example, tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate or trimers of these isocyanate compounds, and excess of these isocyanate compounds Amount and, for example, ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, low-molecular-weight active hydrogen compounds such as triethanolamine or various polyester polyols,
Examples of the compound include a terminal isocyanate group-containing compound obtained by reacting a polyether polyol, a polyamide with a polymer active hydrogen compound, or the like.

The isocyanate compound may be a blocked isocyanate. As the isocyanate blocking agent, for example, phenol, thiophenol,
Phenols such as methylthiophenol, ethylthiophenol, cresol, xylenol, resorcinol, nitrophenol, chlorophenol, acetoxime, methylethylketoxime, cyclohexanone oxime and its oximes, alcohols such as methanol, ethanol, propanol and butanol, ethylene chlorohydroxide Phosphorus, halogen-substituted alcohols such as 1,3-dichloro-2-propanol, t-butanol, t-
Tertiary alcohols such as pentanol, ε-caprolactam, δ-valerolactam, γ-butyrolactam,
lactams such as β-propyrolactam; and other active methylene compounds such as aromatic amines, imides, acetylacetone, acetoacetate, and malonic acid ethyl ester; mercaptans, imines, ureas, and diaryls. Compounds such as sodium bisulfite are also included. The blocked isocyanate can be obtained by subjecting the above isocyanate compound to an isocyanate blocking agent to undergo an addition reaction by a conventionally known appropriate method.

As the epoxy compound, bisphenol A
Diglycidyl ethers and oligomers thereof, diglycidyl ethers of hydrogenated bisphenol A and oligomers thereof, diglycidyl orthophthalate, diglycidyl isophthalate, diglycidyl terephthalate, diglycidyl p-oxybenzoate, tetrahydrophthalate Acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,4-butanediol di Glycidyl ether, 1,6-hexanediol diglycidyl ether and polyalkylene glycol diglycidyl ethers, trime Triglycidyl citrate, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, trimethylol ethane triglycidyl ether, trimethylol propane triglycidyl ether, pentaerythritol tetraglycidyl ether And glycerol alkylene oxide adduct triglycidyl ether.

These curing agents may be used in combination with known curing accelerators selected according to their types.

The resin composition for coating of the present invention is used by dissolving or dispersing in an organic solvent or water. As the organic solvent used, for example, toluene, xylene, cellosolve acetate,
General-purpose solvents such as ethyl acetate, butyl acetate, cyclohexanone, methyl ethyl ketone, isophorone, aromatic hydrocarbons such as Solvesso 100 and Solvesso 150 (Exxon Chemical Co., Ltd.).

The resin composition for coating of the present invention has high hardness,
Since it has high gloss and transparency, it is suitable as a clear paint, but of course, it can be colored by blending and dispersing a pigment. There is no limitation on the type of pigment to be compounded. For example, various titanium oxide pigments, iron oxide (bengala), graphite, molybdate orange, cadmium pigment, inorganic color pigments such as carbon black, copper phthalocyanine green or blue Organic pigments such as pigments, cyclic high-grade pigments, soluble azo pigments and dyed pigments; inorganic pigments such as barium sulfate, zinc white, talc, clay, calcium carbonate and silica; (meth) acrylic beads, acrylonitrile beads, A crystalline polyester resin powder which is difficult to be used as a solvent for the coating material is exemplified.

The resin composition for paints of the present invention also comprises
More than one additive may be mixed. The additives used are not particularly limited, and include, for example, various leveling agents commonly used for paints, pigment dispersants, ultraviolet absorbers,
Antioxidants, viscosity modifiers, light stabilizers, metal deactivators,
Peroxide decomposers, fillers, reinforcing agents, plasticizers, lubricants, anticorrosives, rust inhibitors, emulsifiers, mold decolorizers, fluorescent brighteners, organic flame retardants, inorganic flame retardants, dripping inhibitors , A melt flow modifier, an antistatic agent and the like. Suitable additives mentioned above are exemplified in Canadian Patent No. 1,190,038.

The film-forming composition of the present invention may be, for example, an inorganic material such as aluminum, stainless steel, galvanized iron, tinplate, steel plate, concrete, mortar, slate, or glass, or an organic material such as polycarbonate, polymethyl methacrylate, polyethylene terephthalate, or paper. A film can be formed on a substrate or a film. Also immersion,
It can be applied by a conventional method such as spraying, brush coating, roll coating, spin coating, bar coating and the like.

The resin composition for coatings of the present invention can be dried at room temperature or forcibly dried at about 80 to 100 ° C. when no curing agent is added. In the case of a two-pack paint using isocyanate as a curing agent, it can be dried and cured at room temperature or at 80 to 100 ° C. Further, baking and drying are performed depending on the type of the curing agent. In this case, for example, 15 to 100 to 200 ° C.
Baking is performed at 180 to 250 ° C. for about 30 seconds to about 2 minutes. By blending a curing agent, solvent resistance is exhibited, the coating film becomes tough, and various coating film properties are improved.

[0052]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments. In the examples, “parts” means “parts by weight”. Each measurement item followed the following method.

1. Number average molecular weight (Preparation of sample) Using tetrahydrofuran as solvent, polymerizable polysiloxane or organic polymer (P)
0.05 g was dissolved in 1 g of tetrahydrofuran to prepare a sample. (Apparatus) High-speed GPC device 150 manufactured by Waters Corporation
c was used. (Standard polystyrene) TSK standard polystyrene manufactured by Tosoh Corporation was used. (Measurement conditions) Measurement was performed at a measurement temperature of 35 ° C. and a flow rate of 1 ml / min.

2. Glass transition temperature SC-5200 differential scanning calorimeter (DS manufactured by Seiko Co., Ltd.)
C) was measured at a heating rate of 20 ° C./min. For the sample, put 5 mg of the sample in an aluminum holding lid type container,
It was used after crimping.

3. Acid value 0.2 g of sample was precisely weighed and dissolved in 20 ml of chloroform. Then, it was determined by titration with 0.01 N potassium hydroxide (ethanol solution). Phenolphthalein was used as the indicator.

4. Measurement of Sulfur Content in Organic Resin The organic resin was treated by an oxygen flask combustion method and measured by ion chromatography.

5. Average particle diameter of inorganic fine particles Measured at 23 ° C. by dynamic light scattering measurement using the following apparatus. The measured average particle diameter is a volume average particle diameter. Apparatus: Submicron particle size analyzer (NICOMP MODEL 370, manufactured by Nozaki Sangyo Co., Ltd.) Measurement sample: An ultrasonic dispersion in tetrahydrofuran having an inorganic fine particle concentration of 0.1 to 2.0% by weight was used.

6. Paint stability A predetermined amount of the inorganic fine particle dispersion was blended with a resin solution in which an organic resin and, if necessary, a curing agent were dissolved in a predetermined solvent, and stirred to prepare a resin solution for paint. The obtained paint resin was
Stored at 0 ° C. for 1 month. The paint stability was evaluated by the aggregation, sedimentation, and change in viscosity of the particles of the paint resin. The evaluation criteria are shown below. ：: No aggregation, sedimentation or increase in viscosity of the particles was observed. Δ: Aggregation and sedimentation of the particles are observed or the viscosity increases. X: Aggregation and sedimentation of particles are remarkably observed or viscosity is significantly increased.

7. Stain resistance (magic stain resistance) A line was drawn with red magic on the coated surface of the steel sheet, left for 2 hours, and then wiped off with ethanol to evaluate a mark of the magic on a five-point scale. (5: no trace, 1: complete trace)

8. Hardness The coated surface of the steel plate was measured using a high-grade pencil specified in JIS S-6006 in accordance with JIS K-5400, and judged by the presence or absence of scratches.

9. Workability The coated steel sheet was bent at 180 degrees, and cracks generated at the bent portions were observed and judged with a 10-fold loupe. 3T refers to a case where three sheets of the same thickness are sandwiched in the bent portion, and 0T refers to a case where the sheet is folded 180 degrees without sandwiching the board.

10. Gloss A 60 degree reflectance was measured.

11. Weather resistance The gloss retention was shown after irradiation for 2000 hours using an accelerated weather resistance tester QUV. QUV irradiation condition UV60 ℃ × 4
Time, 8 hours of dew condensation 50 ° C × 4 hours as one cycle,
250 cycles were performed.

Synthesis Example of Polyester Resin Containing Ionic Group (A) 213 parts of terephthalic acid, 175 parts of isophthalic acid, 156 parts of ethylene glycol, neopentyl glycol in a reaction vessel equipped with a stirrer, a condenser and a thermometer.
172 parts, 9 parts of 5-sulfosodium isophthalic acid,
0.255 parts of tetrabutyl titanate was charged, and 16
The esterification reaction was performed from 0 ° C. to 240 ° C. for 4 hours. Then, the pressure inside the system was gradually reduced, and the pressure was reduced to 5 mmHg over 50 minutes, and the polycondensation reaction was further performed at 250 ° C. for 30 minutes under a vacuum of 0.3 mmHg or less. As a result of composition analysis such as NMR, the obtained polyester resin (A) has a molar ratio of an acid component of terephthalic acid / isosophtalic acid /
5-Sulfonatotriuisophthalic acid = 53/45/2
And the glycol component was ethylene glycol / neopentyl glycol = 42/58 in a molar ratio. The number average molecular weight was measured to be 3000, and the glass transition temperature was 56 ° C. The results are shown in Table 1. Hereinafter, polyester resins (B) to (F) having the compositions shown in Table 1 were synthesized by a method according to the above synthesis example.

[0065]

[Table 1] Comparative polyesters (K) to (L) were synthesized in Table 2 by the method according to the above synthesis example.

[0066]

[Table 2]

Synthesis Example (G) of Urethane-Modified Polyester Resin Containing Ionic Group Copolyester resin (A) obtained in Synthesis Example (A)
After 100 parts and 100 parts of toluene were charged and dissolved, toluene 2
Zero parts were distilled and the reaction system was dehydrated by azeotropic distillation of toluene / water. After cooling to 60 ° C., 80 parts of methyl ethyl ketone, 5 g of neopentyl glycol and 18 parts of isophorone diisocyanate were added. Further, after adding 0.03 parts of dibutyltin dilaurate as a reaction catalyst, the mixture was heated at 80 ° C. for 6 hours, and then 65 parts of toluene and 147 parts of cyclohexanone were added to obtain a polyester urethane resin solution (G) having a solid concentration of 30%. . Table 3 shows the composition and characteristic values of the obtained polyester urethane resin solution (G).

[0068]

[Table 3]

Hereinafter, Table 3 was obtained by the method according to the above synthesis example.
The urethane-modified polyester resin (H) having the composition shown in the following was synthesized. (M) and (N) having the compositions shown in Table 4 were synthesized as comparative urethane-modified polyester resins by a method according to the above synthesis example.

[0070]

[Table 4]

Synthesis Example of Acrylic-Modified Polyester Resin Containing Ionic Group (A-1) 466 parts of dimethyl terephthalate, 466 parts of dimethyl isophthalate were placed in a stainless steel autoclave equipped with a stirrer, a thermometer and a partial reflux condenser. 5-
59 parts of sulfonatolithium isophthalic acid, 401 parts of neopentyl glycol, 443 parts of ethylene glycol, and 0.52 part of tetra-n-butyl titanate were charged, and a transesterification reaction was performed at 160 to 220 ° C. for 4 hours. After cooling to 200 ° C., 23 parts of fumaric acid was added, and the temperature was raised from 200 ° C. to 220 ° C. over 1 hour to carry out an esterification reaction. Then the temperature was raised to 255 ° C,
After gradually reducing the pressure of the reaction system, the reaction was carried out under a reduced pressure of 0.2 mmHg for 1 hour and 30 minutes to obtain a modified base polyester resin (A-1). The obtained polyester resin (A-
1) was pale yellow and transparent, and had a number average molecular weight of 12,000. Table 5 shows the results of composition analysis measured by NMR and the like.

[0072]

[Table 5]

In a reactor equipped with a stirrer, a thermometer, a reflux device, and a metering dropping device, a modified base polyester resin (A-
1) 75 parts, 56 parts of methyl ethyl ketone and 19 parts of isopropyl alcohol were added, and heated and stirred at 65 ° C. to dissolve the resin. After the resin was completely dissolved, a mixture of 25 parts of ethyl acrylate and a solution of 1.2 parts of azobisdimethyl valeronitrile dissolved in 25 parts of methyl ethyl ketone were added to 0.1%.
The solution was dropped into the polyester solution at 2 ml / min, and stirring was continued for another 2 hours. The obtained acrylic-modified polyester (I) was pale yellow and transparent, and had a number average molecular weight of 14,000. Table 6 shows the results of composition analysis measured by NMR and the like.

[0074]

[Table 6]

Hereinafter, Table 5 was prepared by the method according to the above synthesis example.
The base polyester resin (B-1) having the composition shown in Table 1 was synthesized. (K-1) and (L-1) having the compositions shown in Table 7 were synthesized as comparative base polyester resins by a method according to the above synthesis example.

[0076]

[Table 7]

Hereinafter, Table 6 was prepared by the method according to the above synthesis example.
An acrylic-modified polyester resin (J) having the composition shown in Table 8 was synthesized, and (O) and (P) having the compositions shown in Table 8 were synthesized as comparative acrylic-modified polyester resins by the method according to the above synthesis example.

[0078]

[Table 8]

Example 1 Polyester (A) was converted to cyclohexanone / solvesso
150 = 50/50 weight part of resin solution dissolved in 50/50 weight ratio, solvent-dispersed colloidal silica MIBK-ST
(Nissan Chemical Co., Ltd.) 50 solid parts and 125 parts of titanium oxide were dispersed with a glass bead type high-speed shaker for 5 hours to obtain a coating composition. The resulting paint exhibited good paint stability.

This coating composition was applied to a 0.5 mm thick zinc iron plate so as to have a thickness of 20 μm, and baked at 230 ° C. for 1 minute. The obtained coating film had good workability and hardness, and also had excellent magic stain resistance. Further, even after the weather resistance test, the gloss retention of 70% or more was maintained. The test results are shown in Table 9.

[0081]

[Table 9] 1) MIBK-ST: solvent-dispersed colloidal silica, solvent used MIBK, average particle diameter 10 nm (manufactured by Nissan Chemical Industries, Ltd.) IPA-ST-ZL: solvent-dispersed colloidal silica, solvent used IPA, average particle diameter 100 nm (Nissan Chemical Co., Ltd.
2) C3600, C3300, C3000: a mixture of (meth) acrylate-based organic-inorganic hybrid colloidal silica having an average particle size of 15 nm and a (meth) acrylate-based resin, and a solvent used butyl acetate / xylene (Nippon Shokubai Co., Ltd. 3) Alkyl etherified aminoformaldehyde resin (manufactured by Mitsui Cytec Co., Ltd.) 4) Blocked isocyanate IPDI system (manufactured by Huls Inc.) 5) CHX: cyclohexanone S150: Solvesso 150 (Exxon Chemical Co., Ltd.)
BA): butyl acetate XL: xylene IPA: isopropyl alcohol MIBK: methyl isobutyl ketone

Example 2 Polyester (B) was converted to cyclohexanone / solvesso
150 = 50/50 weight ratio of a resin solution dissolved in a 50/50 weight ratio, C-3600 which is a mixture of a solvent-dispersed (meth) acrylate organic-inorganic hybrid colloidal silica and a (meth) acrylate resin, 50 parts by weight of Catalyst Co., Ltd. and 125 parts of titanium oxide were dispersed in a glass bead-type high-speed shaker for 5 hours to obtain a coating composition. The resulting paint exhibited good paint stability.

This coating composition was applied to a 0.5 mm thick zinc-iron plate so as to have a thickness of 20 μm, and baked at 230 ° C. for 1 minute. The obtained coating film had good workability and hardness, and also had excellent magic stain resistance. Further, even after the weather resistance test, the gloss retention of 90% or more was maintained. The test results are shown in Table 9.

Example 3 Polyester (B) was converted to cyclohexanone / solvesso
150 = 50/50 weight ratio of a resin solution dissolved in a 50/50 weight ratio, C-3600 which is a mixture of a solvent-dispersed (meth) acrylate organic-inorganic hybrid colloidal silica and a (meth) acrylate resin, 31.3 parts of 50 solid parts and methyl / butyl mixed etherified methylol melamine (trade name: Cymel 254, nonvolatile content 80%, manufactured by Mitsui Cyanamid), p-
2.5 parts of a 10% benzyl alcohol solution of toluenesulfonic acid and 0.5 part of Polyflow S (manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.) were added, and the mixture was added with a glass bead-type high-speed shaker.
Time-dispersed to give a coating composition. The coating composition was applied to a 0.5 mm thick zinc iron plate so as to have a thickness of 20 μm, and baked at 230 ° C. for 1 minute. The obtained coating film had good workability and hardness, and also had excellent magic stain resistance and water resistance. Further, even after the weather resistance test, the gloss retention of 90% or more was maintained. The test results are shown in Table 9.

The coating compositions of Examples 3 to 21 were prepared in the same manner with the compositions shown in Tables 9 to 11 and applied and baked. Tables 9 to 11 show the test results of the obtained coated steel sheets. However, the mixing ratio of the paint was shown in terms of solid content.

[0086]

[Table 10]

1) MIBK-ST: solvent-dispersed colloidal silica, solvent used MIBK, average particle size 10 nm
(Nissan Chemical Co., Ltd.) 2) C3600, C3300: (meth) acrylate based organic-inorganic hybrid colloidal silica average particle size 15 n
Mixture of m and (meth) acrylate resin, solvent used Butyl acetate / xylene (Nippon Shokubai Co., Ltd.) 3) Acrylic resin, solvent used xylene / butyl acetate (Nippon Shokubai Co., Ltd.) 4) Block isocyanate IPDI system (manufactured by Huls Corporation) 5) CHX: cyclohexanone S150: solvesso 150 (Exxon Chemical Co., Ltd.)
BA): butyl acetate XL: xylene IPA: isopropyl alcohol MIBK: methyl isobutyl ketone

[0088]

[Table 11]

1) C3600, C3300, C300
0: Mixture of (meth) acrylate-based organic-inorganic hybrid colloidal silica having an average particle size of 15 nm and (meth) acrylate-based resin, solvent used: butyl acetate / xylene (manufactured by Nippon Shokubai Co., Ltd.) 2) MR110: chloride Vinyl copolymer (manufactured by Zeon Corporation) 3) Blocked isocyanate IPDI (manufactured by Huls) 4) CHX: cyclohexanone S150: solvesso 150 (Exxon Chemical Co., Ltd.)
BA): butyl acetate XL: xylene IPA: isopropyl alcohol MIBK: methyl isobutyl ketone

The coating compositions of Comparative Examples 1 to 8 were prepared, applied and baked. Tables 12 and 13 show the test results of the obtained coated steel sheets. However, the mixing ratio of the paint was shown in terms of solid content.

[0091]

[Table 12]

1) C3600, C3300, C300
0: A mixture of (meth) acrylate-based organic-inorganic hybrid colloidal silica having an average particle size of 15 nm and (meth) acrylate-based resin, solvent used: butyl acetate / xylene (manufactured by Nippon Shokubai Co., Ltd.) 2) Block isocyanate IPDI 3) CHX: cyclohexanone S150: Solvesso 150 (Exxon Chemical Co., Ltd.)
BA): butyl acetate XL: xylene IPA: isopropyl alcohol MIBK: methyl isobutyl ketone

[0093]

[Table 13]

1) C3600: (meth) acrylate based organic-inorganic hybrid type colloidal silica average particle size 15n
Mixture of m and (meth) acrylic ester resin, solvent used: butyl acetate / xylene (manufactured by Nippon Shokubai Co., Ltd.) 2) Blocked isocyanate IPDI system (manufactured by Huls Co., Ltd.) 3) CHX: cyclohexanone S150: solvesso 150 ( Exxon Chemical Co., Ltd.
BA): butyl acetate XL: xylene IPA: isopropyl alcohol MIBK: methyl isobutyl ketone 4) Workability XX: The workability is remarkably poor, and cracks are generated even when bent gently.

[0095]

Industrial Applicability The coating composition of the present invention significantly improves the coating stability of a system containing inorganic fine particles such as colloidal silica, and has excellent coating film properties such as excellent gloss and adhesion, hardness and workability. It has a high degree of compatibility between stain resistance and water resistance, and more surprisingly, it has excellent weather resistance that cannot be obtained by the prior art, and is used in home appliances, food and beverages, including for building materials and outdoors. It can meet the high required quality in the field of cans and the like. Further, the polyester resin used in the present invention is not only a coating composition, but also a single resin,
Alternatively, by using in combination with a known curing agent, various substrates, for example, a plastic film such as polyethylene terephthalate, iron, an adhesive such as a metal plate such as tinplate, or can be used as a binder for various pigments. .

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 4J038 CC062 CD071 CG032 CG141 CG142 DB161 DB291 DB471 DD101 DD241 DD242 DG091 DG111 DL151 EA011 EA012 GA06 GA13 GA14 HA216 HA446 KA08 KA20 NA01 NA03 NA05 NA11 NA12 NA26 4J05 AD05 AF05 AF05 AF05 AF06 AF07 BA12 BA13 BA32 BA35 BA39 EA33 EA34 EA36 EA44 EA48

Claims (4)

[Claims] 1. A coating resin composition comprising an organic resin containing an ionic group (A) and inorganic fine particles (B) having an average particle size of 5 to 200 nm. 2. The coating resin composition according to claim 1, wherein the ionic group contained in the organic resin (A) containing an ionic group is a salt of a compound containing sulfur. 3. The coating resin composition according to claim 1, wherein the organic resin (A) containing an ionic group is a polyester and / or a modified polyester. 4. The method according to claim 1, wherein all or a part of the inorganic fine particles (B) are organic-inorganic composite fine particles in which an organic resin is fixed on the surface of the inorganic fine particles. Resin composition for paint.