JP6505676B2 - Coating composition, coated article and coating film forming method - Google Patents

Description

(Cross-reference to related fields)
This application claims the benefit of the priority of Japanese Patent Application No. 2014-107159, filed May 23, 2014, which is incorporated herein by reference in its entirety.
(Technical field)
The present invention relates to a coating composition, a coated article and a method of forming a coating film.

  Conventionally, the conductive paint composition is used for various objects to be coated and applications such as conductive primers, antistatic paints of various plastic materials, highly conductive paints, etc., depending on the surface resistance value of the cured coating film obtained. It is done. As such a conductive paint composition, for example, a conductive paint composition obtained by dispersing a conductivity imparting agent such as a conductive pigment powder in a binder resin solution such as a thermoplastic resin or a thermosetting resin. Are widely used. It has been proposed to add a silane coupling agent to the conductive coating composition for the purpose of improving the adhesion to a substrate. For example, Patent Document 1 proposes a conductive paint containing a thermoplastic acrylic resin, a nickel powder having an average particle size of 30 μm or less, and a silane coupling agent contained in a specific amount range, and an organic solvent. Patent Document 2 proposes a conductive paint comprising nickel powder having an average particle size of 30 μm or less, a thermoplastic acrylic resin having a glass transition temperature of 20 ° C. or more, a specific titanate coupling agent and an organic solvent. It is done. However, none of the coating compositions described in Patent Document 1 and Patent Document 2 satisfy long-term storage stability, and the storage of the coating composition is influenced by moisture and other components such as a conductivity imparting agent. There is a problem that the stability is deteriorated, and in particular, the adhesion ability of the formed coating film after long-term storage is inferior.

Unexamined-Japanese-Patent No. 2006-169349 JP 2007-106788 A

  The present invention has been made in view of the above circumstances, and the object of the present invention is that the storage stability of the coating is good even when it contains a conductivity imparting agent, and the adhesion to the object to be obtained is extremely high. A coating composition, a coated article and a method for forming a coating film which can form an excellent coating film.

  Under these circumstances, as a result of intensive studies, the present inventors have found that the above problems can be solved by blending a specific silane coupling agent.

That is, the present invention provides a coating composition and a coating film forming method described in the following items:
Item 1. A coating composition comprising (A) a hydroxyl group-containing resin having an acid value of less than 10 mg KOH / g, (B) a conductivity imparting agent, and (C) a silane coupling agent containing one or more carbodiimide groups in the molecule. The solid content of the conductivity imparting agent (B) is in the range of 25 to 500 parts by mass based on 100 parts by mass of the resin solid content of the hydroxyl group-containing resin (A) having an acid value of less than 10 mg KOH / g. And a solid content of the silane coupling agent (C) is 1 to 30 parts by mass.

  Item 2. The coating composition according to item 1, wherein a part or all of the conductivity imparting agent (B) is a conductive carbon black.

  Item 3. The coating composition according to Item 1 or 2, wherein the weight average molecular weight of the silane coupling agent (C) is 500 to 10,000.

  Item 4. The coating composition according to any one of Items 1 to 3, wherein the number of equivalents of the carbodiimide group in the silane coupling agent (C) is 300 to 2,000.

  Item 5. The coating composition according to any one of Items 1 to 4, further containing a crosslinking agent (D).

  Item 6. The coating composition according to any one of Items 1 to 5, further comprising a cellulose derivative (E).

  Item 7. The coating composition according to any one of Items 1 to 6, further containing a coloring component (F).

  Item 8. Item 9. A coated article obtained by applying the coating composition according to any one of Items 1 to 7 on a substrate.

  Item 9. The process of coating the coating material of any one of claim | item 1-7 to a to-be-coated-article, the process of forming a undercoat, and coating a topcoat coating composition on this undercoat, and topcoat coating A method of forming a coating film, comprising the step of forming

  The coating composition of the present invention is less susceptible to moisture and other components such as a conductivity imparting agent by using a specific silane coupling agent, has a long-term storage stability, and is coated after being stored for a long period of time. Even when the coating film is formed, the coating film exhibits an effect of being extremely excellent in adhesion to the object to be coated.

Coating Composition The present invention comprises (A) a hydroxyl group-containing resin having an acid value of less than 10 mg KOH / g, (B) a conductivity imparting agent, and (C) a coupling agent containing one or more carbodiimide groups in the molecule. Paint composition.

(A) Hydroxyl Group-Containing Resin As the hydroxyl group-containing resin (A) of the present invention, conventionally known resins for paint can be used, and examples thereof include a hydroxyl group-containing acrylic resin, a hydroxyl group-containing polyester resin, and a hydroxyl group-containing polyurethane resin. It is preferable to use a resin such as a hydroxyl group-containing acrylic resin, a hydroxyl group-containing polyester resin, and a modified resin thereof from the viewpoint of the weather resistance and heat resistance of the resulting coating film. These hydroxyl group-containing resins can be used singly or in combination of two or more. From the viewpoint of storage stability of the coating composition, the acid value of the entire hydroxyl group-containing resin is less than 10 mg KOH / g. The compounding amount is preferably adjusted so that the acid value of the hydroxyl group-containing resin is in the range of 0 to 5 mg KOH / g.

  The above hydroxyl group-containing acrylic resin is usually obtained by copolymerizing a hydroxyl group-containing polymerizable unsaturated monomer and another polymerizable unsaturated monomer copolymerizable with the hydroxyl group-containing polymerizable unsaturated monomer by a method known per se It can be manufactured.

  The hydroxyl group-containing polymerizable unsaturated monomer is a compound having one or more hydroxyl group and one or more polymerizable unsaturated bond in one molecule, and specifically, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxy A monoester of (meth) acrylic acid and a C 2-8 dihydric alcohol such as propyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, etc .; Ε-caprolactone modified product of monoester of acrylic acid and dihydric alcohol having 2 to 8 carbon atoms; N-hydroxymethyl (meth) acrylamide; allyl alcohol, having a polyoxyethylene chain whose molecular terminal is a hydroxyl group (meth Acrylate etc. can be mentioned.

  Further, as another polymerizable unsaturated monomer copolymerizable with the hydroxyl group-containing polymerizable unsaturated monomer, for example, alkyl or cycloalkyl (meth) acrylate, a polymerizable unsaturated monomer having an isobornyl group, polymerization having an adamantyl group Unsaturated monomer, vinyl aromatic compound, polymerizable unsaturated monomer having alkoxysilyl group, perfluoroalkyl (meth) acrylate, polymerizable unsaturated monomer having fluorinated alkyl group, polymerizable having photopolymerizable functional group Unsaturated monomers, vinyl monomers, carboxyl group-containing polymerizable unsaturated monomers, nitrogen-containing polymerizable unsaturated monomers, polymerizable unsaturated monomers having two or more polymerizable unsaturated groups in one molecule, epoxy group-containing polymerizable impurities Saturated monomer, having polyoxyethylene chain whose molecular end is alkoxy group (Meth) acrylate, polymerizable unsaturated monomer having a sulfonic acid group, polymerizable unsaturated monomer having a phosphoric acid group, polymerizable unsaturated monomer having an ultraviolet ray absorbing functional group, ultraviolet ray stable polymerizable unsaturated monomer, a carbonyl And polymerizable unsaturated monomer compounds having a group. These can be used alone or in combination of two or more.

  As alkyl or cycloalkyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (Meth) acrylate, tert-butyl (meth) acrylate, n-hexyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, tridecyl (meth) acrylate, lauryl (Meth) acrylate, stearyl (meth) acrylate, "isostearyl acrylate" (trade name, manufactured by Osaka Organic Chemical Industry Ltd.), cyclohexyl (meth) acrylate, methyl cyclohexyl (meth) acrylate, t-butyl ester Rohekishiru (meth) acrylate, cyclododecyl (meth) acrylate.

Examples of the polymerizable unsaturated monomer having an isobornyl group include isobornyl (meth) acrylate and the like.
Examples of the polymerizable unsaturated monomer having an adamantyl group include adamantyl (meth) acrylate and the like.
Examples of the vinyl aromatic compound include styrene, α-methylstyrene, vinyl toluene and the like.

As a polymerizable unsaturated monomer having an alkoxysilyl group, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, γ- (meth) acryloyloxypropyltrimethoxysilane, γ- (meth) acryloylyl An oxypropyl triethoxysilane etc. are mentioned.
As perfluoroalkyl (meth) acrylate, perfluorobutylethyl (meth) acrylate, perfluorooctylethyl (meth) acrylate and the like can be mentioned.
Examples of the polymerizable unsaturated monomer having a fluorinated alkyl group include fluoroolefins and the like.

Examples of the polymerizable unsaturated monomer having a photopolymerizable functional group include polymerizable unsaturated monomers having a maleimide group.
Examples of the vinyl monomer include N-vinylpyrrolidone, ethylene, butadiene, chloroprene, vinyl propionate, and vinyl acetate.

Examples of the carboxyl group-containing polymerizable unsaturated monomer include (meth) acrylic acid, maleic acid, crotonic acid, β-carboxyethyl (meth) acrylate and the like.
As the nitrogen-containing polymerizable unsaturated monomer, (meth) acrylonitrile, (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylamide, glycidyl (meth) acrylate and the like An adduct with an amine compound may, for example, be mentioned.

Examples of the polymerizable unsaturated monomer having two or more polymerizable unsaturated groups in one molecule include allyl (meth) acrylate and 1,6-hexanediol di (meth) acrylate.
As the epoxy group-containing polymerizable unsaturated monomer, glycidyl (meth) acrylate, β-methyl glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 3,4-epoxycyclohexylethyl (meth) acrylate, 3,4-epoxycyclohexylpropyl (meth) acrylate, allyl glycidyl ether and the like can be mentioned.

Examples of the polymerizable unsaturated monomer having a sulfonic acid group include 2-acrylamido-2-methylpropane sulfonic acid, allyl sulfonic acid, styrene sulfonic acid sodium salt, sulfoethyl methacrylate and its sodium salt, ammonium salt and the like.
Examples of the polymerizable unsaturated monomer having a phosphoric acid group include 2-acryloyloxyethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, 2-acryloyloxypropyl acid phosphate, 2-methacryloyloxypropyl acid phosphate and the like.

  As a polymerizable unsaturated monomer having a UV absorbing functional group, 2-hydroxy-4- (3-methacryloyloxy-2-hydroxypropoxy) benzophenone, 2-hydroxy-4- (3-acryloyloxy-2-hydroxypropoxy) ) Benzophenone, 2,2'-dihydroxy-4- (3-methacryloyloxy-2-hydroxypropoxy) benzophenone, 2,2'-dihydroxy-4- (3-acryloyloxy-2-hydroxypropoxy) benzophenone, 2- (2) 2'-hydroxy-5'-methacryloyloxyethylphenyl) -2H-benzotriazole etc. are mentioned.

  As a UV-stable polymerizable unsaturated monomer, 4- (meth) acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4- (meth) acryloyloxy-2,2,6,6-tetra Methyl piperidine, 4-cyano-4- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine, 1- (meth) acryloyl-4- (meth) acryloylamino-2,2,6,6- Tetramethylpiperidine, 1- (meth) acryloyl-4-cyano-4- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-2,2,6,6-tetra Methyl piperidine, 4-crotonoylamino-2,2,6,6-tetramethylpiperidine, 1-crotonoyl-4-crotonoyloxy-2,2,6,6 Tetramethylpiperidine, and the like.

  As polymerizable unsaturated monomer compounds having a carbonyl group, acrolein, diacetone acrylamide, diacetone methacrylamide, acetoacetoxyethyl methacrylate, formyl styrene, vinyl alkyl ketone having 4 to 7 carbon atoms (eg, vinyl methyl ketone) , Vinyl ethyl ketone, vinyl butyl ketone) and the like.

  In this specification, "(meth) acrylate" is "acrylate or methacrylate", "(meth) acrylic acid" is "acrylic acid or methacrylic acid", "(meth) acryloyl" is "acryloyl or methacryloyl", " The term "(meth) acrylamide" means "acrylamide or methacrylamide", and "(meth) acrylonitrile" means "acrylonitrile or methacrylonitrile".

  The polymerization method for obtaining the above-mentioned hydroxyl group-containing acrylic resin (A) is not particularly limited. For example, bulk polymerization method, solution polymerization method and the like can be mentioned in the presence of a radical polymerization initiator. A polymerization method can be suitably used.

  As the polymerization method by the solution polymerization method, for example, the monomer mixture is dissolved in an organic solvent, and heating is generally performed while stirring at a temperature of about 80 ° C. to 200 ° C. in the presence of a known radical polymerization initiator. Can be mentioned. The reaction time can usually be about 1 to 24 hours.

  The hydroxyl group-containing acrylic resin (A) can be used singly or in combination of two or more.

  The hydroxyl value of the hydroxyl group-containing acrylic resin is generally in the range of 30 to 300 mg KOH / g, preferably 40 to 250 mg KOH / g, more preferably 50 to 200 mg KOH / g, from the viewpoint of water resistance of the obtained coating.

  The acid value of the hydroxyl group-containing acrylic resin is less than 10 mg KOH / g from the viewpoint of the storage stability of the coating composition. The inside of the range of 0-5 mgKOH / g is preferable.

  In order to make the acid value of the hydroxyl group-containing acrylic resin fall in the above range, the carboxyl group-containing polymerizable unsaturated monomer amount is, for example, less than 2%, and further 0 to less than 1%. Is preferred.

  The weight average molecular weight of the hydroxyl group-containing acrylic resin is not particularly limited, but is preferably 1,000 to 200,000, more preferably 2,000, from the viewpoint of coating physical properties, coating workability and weather resistance. It is preferably in the range of ̃150,000, particularly preferably 5,000-100,000.

  Moreover, in the present specification, the number average molecular weight and the weight average molecular weight are the retention times of standard polystyrenes of known molecular weight whose retention time (retention capacity) measured using gel permeation chromatography (GPC) was measured under the same conditions. (Retention capacity) is a value determined by converting to the molecular weight of polystyrene. Specifically, “HLC 8120 GPC” (trade name, manufactured by Tosoh Corporation) is used as a GPC apparatus, and “TSKgel G-4000HXL”, “TSKgel G-3000HXL”, “TSKgel G-2500HXL”, and “TSKgel” are used as columns. Four G-2000HXL (trade name, all manufactured by Tosoh Corporation) are used, a differential refractometer is used as a detector, a mobile phase: tetrahydrofuran, measurement temperature: 40 ° C., flow rate: 1 mL / min It can be measured under conditions.

  As a hydroxyl group-containing polyester resin, an oil-free polyester resin formed by reacting a polybasic acid, a polyhydric alcohol and, if necessary, an aromatic monobasic acid or a monoalcohol, or a polybasic acid or a polyhydric alcohol with a fatty acid or Examples thereof include oils and fats, and alkyd resins obtained by reacting an aromatic monobasic acid and a monoalcohol as needed.

  As said polybasic acid component, the compound normally used as an acid component can be used in the case of manufacture of polyester resin. As such an acid component, for example, aliphatic polybasic acids, alicyclic polybasic acids, aromatic polybasic acids and the like can be mentioned.

  The above aliphatic polybasic acids are generally aliphatic compounds having two or more carboxyl groups in one molecule, acid anhydrides of the aliphatic compounds and esterified compounds of the aliphatic compounds. As aliphatic polybasic acids, for example, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassic acid, octadecanedioic acid, citric acid, butane Aliphatic polyvalent carboxylic acids such as tetracarboxylic acids; anhydrides of the aliphatic polyvalent carboxylic acids; esters of lower alkyl having about 1 to 4 carbon atoms of the aliphatic polyvalent carboxylic acids, and the like. The said aliphatic polybasic acids can be used individually or in combination of 2 or more types.

  As the above-mentioned aliphatic polybasic acid, it is particularly preferable to use adipic acid and / or adipic acid anhydride from the viewpoint of smoothness, sharpness and the like of the resulting coating film.

  The alicyclic polybasic acid is generally a compound having one or more alicyclic structures and two or more carboxyl groups in one molecule, an acid anhydride of the compound and an esterified product of the compound. Alicyclic structures are primarily 4 to 6 membered ring structures. As an alicyclic polybasic acid, for example, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, 3-methyl- Alicyclic polyvalent carboxylic acids such as 1,2-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohexanedicarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,3,5-cyclohexanetricarboxylic acid; Anhydrides of alicyclic polyhydric carboxylic acids; Esters of lower alkyl having about 1 to 4 carbon atoms of the alicyclic polyhydric carboxylic acids, and the like can be mentioned. The above-mentioned alicyclic polybasic acids can be used alone or in combination of two or more.

  As the above-mentioned alicyclic polybasic acid, from the viewpoints of smoothness, sharpness and the like of the obtained coating film, 1,2-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid anhydride, 1,3-cyclohexanedicarboxylic acid It is preferable to use an acid, 1,4-cyclohexanedicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, and 4-cyclohexene-1,2-dicarboxylic acid anhydride, and among them, 1,2-cyclohexanedicarboxylic acid It is more preferable to use and / or 1,2-cyclohexanedicarboxylic acid anhydride.

  The aromatic polybasic acid is generally an aromatic compound having two or more carboxyl groups in one molecule, an acid anhydride of the aromatic compound and an esterified product of the aromatic compound, such as phthalic acid. And aromatic polyvalent carboxylic acids such as isophthalic acid, terephthalic acid, naphthalene dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid, trimellitic acid, pyromellitic acid; anhydrides of the aromatic polyvalent carboxylic acids; the aromatics Examples thereof include esters of lower alkyl having about 1 to 4 carbon atoms of a polyvalent carboxylic acid. The above-mentioned aromatic polybasic acids can be used alone or in combination of two or more.

  As the aromatic polybasic acid, phthalic acid, phthalic anhydride, isophthalic acid, trimellitic acid and trimellitic anhydride are preferably used.

  Moreover, as a fatty acid component used for producing the alkyd resin, for example, coconut oil fatty acid, cottonseed oil fatty acid, hempseed oil fatty acid, rice bran oil fatty acid, fish oil fatty acid, tall oil fatty acid, soybean oil fatty acid, linseed oil fatty acid, soy sauce fatty acid, Fatty acids such as rapeseed oil fatty acid, castor oil fatty acid, dehydrated castor oil fatty acid, safflower oil fatty acid; lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, benzoic acid, p-tert-butyl acid Examples thereof include monocarboxylic acids such as benzoic acid, cyclohexanoic acid and 10-phenyloctadecanoic acid; and hydroxycarboxylic acids such as lactic acid, 3-hydroxybutanoic acid and 3-hydroxy-4-ethoxybenzoic acid. These fatty acid components can be used alone or in combination of two or more.

  Moreover, glycerol esterified substances, such as the said fatty acid, etc. can be mentioned as a fats-and-oils component.

  Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, diethylene glycol, trimethylene glycol, tetraethylene glycol, triethylene glycol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, and the like. -Butanediol, 1,2-butanediol, 2-methyl-1,3-propanediol, 3-methyl-1,2-butanediol, 2-butyl-2-ethyl-1,3-propanediol, 1, 2-pentanediol, 1,5-pentanediol, 1,4-pentanediol, 2,4-pentanediol, 2,3-dimethyltrimethylene glycol, tetramethylene glycol, 3-methyl-4,3-pentanediol, 3-Methyl-1,5-pentanediol, 2 2,4-trimethyl-1,3-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,4-hexanediol, 2,5-hexanediol, neopentyl glycol, 1,4-cyclohexane Dihydric alcohols such as dimethanol, tricyclodecane dimethanol, hydroxypivalic acid neopentyl glycol ester, hydrogenated bisphenol A, hydrogenated bisphenol F, dimethylol propionic acid; and lactone compounds such as ε-caprolactone in these dihydric alcohols Ester added compounds such as bis (hydroxyethyl) terephthalate; alkylene oxide adducts of bisphenol A, polyethylene glycol, polypropylene glycol, polybutylene glycol, etc. Terdiol compounds; glycerin, trimethylolethane, trimethylolpropane, diglycerin, triglycerin, 1,2,6-hexanetriol, pentaerythritol, dipentaerythritol, tris (2-hydroxyethyl) isocyanuric acid, sorbitol, mannitol etc. Alcohols of trivalent or higher; polylactone polyol compounds in which a lactone compound such as ε-caprolactone is added to these alcohols of trivalent or higher; fatty acid esters of glycerin and the like.

  The monoalcohol component is not particularly limited, and examples thereof include monoalcohols such as methanol, ethanol, propyl alcohol, butyl alcohol, stearyl alcohol, 2-phenoxyethanol and the like.

  It is obtained by reacting a monoepoxy compound such as propylene oxide, butylene oxide, "Cardura E10" (trade name, manufactured by Momentive Specialty Chemicals, glycidyl ester of synthetic hyperbranched saturated fatty acid) with an acid as another alcohol component. Alcohol compounds can also be used.

  The method for producing the hydroxyl group-containing polyester resin is not particularly limited, and can be carried out in accordance with a usual method. For example, the acid component and the alcohol component are heated in a nitrogen stream at about 150 to 250 ° C. for about 5 to 10 hours to carry out an esterification reaction or a transesterification reaction of the acid component and the alcohol component, A hydroxyl group-containing polyester resin can be produced.

  When the acid component and the alcohol component are subjected to an esterification reaction or a transesterification reaction, these may be added at once into the reaction vessel, or one or both may be added in several times. Good. In addition, first, after a hydroxyl group-containing polyester resin is synthesized, an acid anhydride is reacted with the obtained hydroxyl group-containing polyester resin to make it half-esterified to form a carboxyl group and a hydroxyl group-containing polyester resin, and the above-mentioned alcohol component is further added. It may be a hydroxyl group-containing polyester resin.

  During the esterification or transesterification reaction, dibutyltin oxide, antimony trioxide, zinc acetate, manganese acetate, cobalt acetate, calcium acetate, lead acetate, tetrabutyl titanate, tetraisopropyl as a catalyst for promoting the reaction Catalysts known per se, such as titanates, can be used.

  The hydroxyl group-containing polyester resin can be modified with a polyisocyanate compound or the like during or after the preparation of the resin.

  Examples of the polyisocyanate compound include aliphatic diisocyanate compounds such as lysine diisocyanate, hexamethylene diisocyanate and trimethylhexane diisocyanate; hydrogenated xylylene diisocyanate, isophorone diisocyanate, methylcyclohexane-2,4-diisocyanate, methylcyclohexane-2, 6 Alicyclic diisocyanate compounds such as diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), 1,3- (isocyanatomethyl) cyclohexane and the like; aromatic diisocyanate compounds such as tolylene diisocyanate, xylylene diisocyanate and diphenylmethane diisocyanate; lysine Organic polyisocyanates such as triisocyanate and trivalent or higher polyisocyanates Itself; adducts of each of these organic polyisocyanates with polyhydric alcohols, low molecular weight polyester resins, water, etc .; cyclized polymers of these respective organic polyisocyanates (eg, isocyanurate), biuret type adducts, etc. Can be mentioned. These polyisocyanate compounds can be used singly or in combination of two or more.

  The hydroxyl value of the hydroxyl group-containing polyester resin is generally 1 to 300 mg KOH / g. From the viewpoint of water resistance of the obtained coating film, it is preferably in the range of 30 to 300 mg KOH / g, more preferably 40 to 250 mg KOH / g, and particularly preferably 50 to 200 mg KOH / g.

  The number average molecular weight of the hydroxyl group-containing polyester resin is generally 500 to 50,000. From the viewpoint of storage stability, it is preferably in the range of 1,000 to 30,000, more preferably 1,200 to 10,000.

  The acid value of the hydroxyl group-containing polyester resin is less than 10 mg KOH / g from the viewpoint of the storage stability of the coating composition. The inside of the range of 0-5 mgKOH / g is preferable.

(B) Conductivity-imparting agent The conductivity-imparting agent used in the paint composition of the present invention makes the surface electric resistance value of the cured coating film formed by the paint composition of the present invention less than 1 × 10 ⁷ Ω / □ For example, conductive carbon black, metal, metal oxide or metal oxide doped, metal coated pigment, carbon fiber (polyacrylonitrile, petroleum refining or coal dry residue by-product Pitch system manufactured from "pitch", graphite, a carbon nanotube, etc. are mentioned.

  The conductive carbon black may be in the form of powder containing carbon as a main component, which may be known per se. For example, those appropriately selected from those obtained by the manufacturing method such as thermal black, furnace black, lamp black, contact black (channel black, roll black, disc black) can be used.

  As the conductive carbon black, a commercially available product can be used. For example, "Vulcan XC-72" (manufactured by Cabot Co., Ltd., trade name), "Ketjen Black EC", "Ketjen Black EC600JD" (manufactured by Lion Akzo Co., Ltd.) , Trade name), "Denka black HS-100" (trade name, acetylene black, manufactured by Denki Kagaku Kogyo Co., Ltd.) and the like.

  Examples of the metal include silver, nickel, copper, zinc, aluminum, stainless metal itself and metal oxides thereof, and powdery, fibrous, flaked, particulate, etc. are appropriately selected and used. it can. Although the size of each powder or the like is not particularly limited, for example, one having an average primary particle diameter of 100 μm or less, particularly 30 μm or less is preferable. In particular, flakes are preferable from the viewpoint of conductivity, in which case, for example, those having a thickness of 0.1 to 5 μm and a major axis of 1 to 100 μm can be mentioned, and further 0.5 to 2 μm thick and a major axis of 5 to 50 μm Are particularly preferred.

  Examples of metal oxides further include tin oxide, zinc oxide, titanium oxide, potassium titanate, indium oxide and the like, and those obtained by doping aluminum, antimony, nickel and the like into these, and the like.

  Examples of the metal-coated pigment include inorganic pigments such as insulating mica, calcium carbonate and glass beads, and pigments obtained by plating and coating aluminum or nickel on the above-mentioned carbon fiber or the like.

  The said conductivity imparting agent can be used individually by 1 type or in mixture of 2 or more types.

  From the viewpoint of high conductivity and storage stability of the coating, conductive carbon black and / or nickel flakes are preferred, and in particular, conductive carbon black is preferably used.

  The said conductivity imparting agent can be directly mix | blended in a coating composition. From the viewpoint of conductivity, it is preferable to blend a pigment dispersion (paste) obtained by mixing and dispersing in advance with a pigment dispersant in a paint. As the pigment dispersant, known ones can be used. The dispersion method can apply a well-known method.

  Examples of the pigment dispersant include low molecular weight surfactants, pigment wetting dispersants, other pigment stabilizers, and mixtures thereof.

  As surfactant, anionic surfactant such as alkyl benzene sulfonate or alkyl naphthalene sulfonate, alkyl sulfo succinate or naphthalene formaldehyde sulfonate; cationic surfactant such as quaternary salt such as benzyl tributyl ammonium chloride; or non-surfactant Mention may be made of ionic or amphoteric surfactants such as polyoxyethylene surfactants and alkyl betaines or amidopropyl betaines.

  As the surfactant, commercially available products can be used, for example, those available under the trade name of KP (products of Shin-Etsu Silicone Co., Ltd.), those available under the trade name of Polyflow (products of Kyoeisha Chemical Co., Ltd.), Available under the F-Top tradename (Mitsubishi Materials Electronic Chemicals, Inc. product), MEGAFAC tradename (DIC product), Fluorad tradename (Sumitomo 3M) Products available under the trade names of Asahi Guard and Surflon (products of Asahi Glass Co., Ltd.), and the like.

  The pigment wetting and dispersing agent can include resins having nonionic or cationic pigment-affinitive groups and nonionic resins. Examples of the pigment affinity group include basic affinity groups such as amide and amine, and acidic affinity groups such as phosphoric acid and carboxylic acid.

  As the pigment wetting and dispersing agent, commercially available products can be used. For example, DISPER BYK (registered trademark) 130, 140, 145, 160, 161, 162, 163, 164, 2050, 2150, 2155, 2164, BYK 9076, 9077, available under the BAFA EFKA (R) trade name Lubrizol's SOLSPERSE (R) trade name 楠 本 化成 36 Disparlon PW-36, DA-325, DA -375, DA-7301, Kyoeisha Chemical's Flowlen DOPA-15B, DOPA-15 BHFS, DOPA-17HF, DOPA-22, DOPA-33, G-600, G-700, G-820, G-900, NC- 500, KDG-2400 etc. can be mentioned.

  Examples of other pigment stabilizers include fatty acids such as stearic acid and behenic acid, and fatty amines such as laurylamine stearylamine. Furthermore, aliphatic alcohols such as 1,2-diol, ethoxylated fatty alcohol polyols, epoxidized soybean oil, waxes, resin acids, resin acid salts and the like can be mentioned.

  These pigment dispersants may be used alone or in mixtures of two or more.

The compounding ratio of the conductivity imparting agent (B) is 25 to 500 parts by mass with respect to 100 parts by mass of the resin solid content of the hydroxyl group-containing resin (A). Preferably it can set suitably in the range of 30-300 mass parts, more preferably 80-250 mass parts. The type of the conductivity imparting agent (B) can be appropriately selected and adjusted so that the cured coating film has a desired surface resistance value, but the surface resistance value is 1 × 10 ³ Ω / □ or less Preferably, conductive carbon black and / or nickel flakes are used.

  When using conductive carbon black as the conductivity imparting agent (B), the blending ratio is usually 25 to 300 parts by mass, preferably 100 parts by mass of the resin solid content of the hydroxyl group-containing resin (A). It can set suitably in 50-250 mass parts, more preferably in the range of 80-250 mass parts.

  When using nickel flakes as the conductivity imparting agent (B), the blending ratio is preferably 25 to 500 parts by mass, more preferably 100 with respect to 100 parts by mass of the resin solid content of the hydroxyl group-containing resin (A). It can set suitably in the range of -300 mass parts.

  When the conductivity imparting agent used in the coating composition of the present invention is dispersed in advance with a pigment dispersant, generally, the amount of the pigment dispersant is 100 parts by mass of the solid content of the conductivity imparting agent (B), It can be appropriately selected in an amount of 50 parts by mass or less, preferably 0 to 30 parts by mass.

(C) Silane Coupling Agent Containing One or More Carbodiimide Groups in Molecule The coating composition of the present invention contains a silane coupling agent containing one or more carbodiimide groups in the molecule.

  The silane coupling agent is a compound containing a hydrolyzable silyl group and / or a silanol group. A hydrolyzable silyl group is a group which produces | generates a silanol group by hydrolysis. Examples of the hydrolyzable silyl group include groups in which an alkoxy group, an aryloxy group, an acetoxy group, a halogen atom or the like is bonded to a silicon atom. Here, the alkoxy group is an alkoxy group having 1 to 8 carbon atoms, the aryloxy group is an aryloxy group having 6 to 18 carbon atoms, and the halogen atom is chlorine and the like.

  The carbodiimide group has the general structural formula -N = C = N- (I). The carbodiimide group can be obtained, for example, by subjecting two isocyanate group-containing compounds to a decarbon dioxide condensation reaction, as represented by the general formula (II).

  The method for synthesizing the component (C) is not particularly limited. For example, a compound obtained by decarbon dioxide condensation reaction of a silane coupling agent containing an isocyanate group and a diisocyanate under a carbodiimidization catalyst Can be mentioned.

  It does not specifically limit as an isocyanate group containing silane coupling agent at the time of synthesize | combining a component (C), For example, 3-isocyanate propyl trimethoxysilane and 3-isocyanate propyl triethoxysilane are mentioned.

  The diisocyanate in synthesizing the component (C) is not particularly limited, and is a compound having at least two isocyanate groups in one molecule, and examples thereof include aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, and the diisocyanates. Derivatives and the like.

  Examples of the aliphatic diisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, and 1,3-butadiene. Examples include butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, dimer acid diisocyanate, methyl 2,6-diisocyanatohexanoate (common name: lysine diisocyanate) and the like.

  Examples of the alicyclic diisocyanate include 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (common name: Isophorone diisocyanate), 4-methyl-1,3-cyclohexylene diisocyanate (conventional name: hydrogenated TDI), 2-methyl-1,3-cyclohexylene diisocyanate, 1,3- or 1,4-bis (isocyanatomethyl) And the like. Cyclohexane (conventional name: hydrogenated xylylene diisocyanate) or a mixture thereof, methylene bis (4,1-cyclohexanediyl) diisocyanate (conventional name: hydrogenated MDI), norbornane diisocyanate and the like can be mentioned.

  Examples of the aromatic diisocyanate include methylene bis (4,1-phenylene) diisocyanate (common name: MDI), 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, ω, ω′-diisocyanato-1, 4-diethylbenzene, 1,3- or 1,4-bis (1-isocyanato-1-methylethyl) benzene (common name: tetramethyl xylylene diisocyanate) or a mixture thereof, m-phenylene diisocyanate, p-phenylene diisocyanate, 4 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, 2,4-tolylene diisocyanate (common name: 2,4-TDI) or 2,6-tolylene diisocyanate (common name: 2,6-TDI) or Its mixture, 4,4'- toluidine An isocyanate, 4,4'- diphenyl ether diisocyanate etc. can be mentioned.

  Moreover, as a derivative of the said diisocyanate, the dimer of the above-mentioned diisocyanate, biuret, allophanate, uretdione, uretimine etc. can be mentioned, for example.

  The above diisocyanates and their derivatives may be used alone or in combination of two or more.

  Examples of the carbodiimidization catalyst include phospholene compounds, phospholene oxide compounds, oxidized phospholene sulfide compounds, etc. Specifically, 1-phenyl-2-phospholene-1-oxide, 3-methyl-2-one Phosphorene oxides such as phosphorene 1-oxide, 1-ethyl 2-phospholene 1-oxide, 3-methyl 1-phenyl 2-phospholene 1-oxide, and 3-phospholene isomers thereof, 2, 5-dihydro-3-methyl-1-phenylphosphol-1-oxide and the like can be used. Among them, 3-methyl-1-phenyl-2-phospholene-1-oxide is preferable from the viewpoint of reactivity.

  The reaction temperature is not particularly limited as long as the carbodiimidization reaction proceeds, and can be appropriately selected within the range of 60 to 250 ° C. Furthermore, when using aliphatic or alicyclic diisocyanate as diisocyanate of a raw material, 120-160 degreeC is preferable, and when using aromatic diisocyanate, 80 degreeC-120 degreeC is preferable. The reaction end point is determined, for example, by measuring the content of isocyanate groups.

  In addition, in this specification, the isocyanate group content rate represents the quantity of the isocyanate group contained in a compound with the mass fraction. The measurement of the amount of the isocyanate group can be performed according to JIS K 1603-1 (2007). Specifically, the reaction can be determined by back titration of unreacted dibutylamine with a standard solution of hydrochloric acid after adding an excess of dibutylamine to the sample to cause sufficient reaction.

  It is also possible to use an organic solvent in the above carbodiimidization reaction. The organic solvent is not particularly limited as long as it is not reactive with the carbodiimide group and the hydrolyzable silyl group. Examples of suitable organic solvents are methyl acetate, ethyl acetate, N-methyl pyrrolidone, dimethylformamide, methoxypropyl acetate, ethoxypropyl acetate, methoxybutyl acetate, ethoxybutyl acetate, diglycol dimethyl ether, diglycol diethyl ether, methyl glycol acetate Ethyl glycol acetate, butyl glycol acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, propylene carbonate, toluene, xylene and the like. At the time of carbodiimidization, since it may be a high temperature of 120 ° C., a solvent having a boiling point of 100 ° C. or more, for example, toluene, xylene or the like is preferable, and after completion of the reaction, the solvent is substituted or diluted with an organic solvent having a boiling point of 100 ° C. May be

  The number of hydrolyzable silyl groups and / or silanol groups in one molecule of the component (C) is preferably 1 or more, more preferably 2 to 200, particularly preferably 5 to 40, from the viewpoint of adhesion.

The number of equivalents of the carbodiimide group of the component (C) is preferably in the range of 300 to 2,000, more preferably 500 to 1,000, from the viewpoint of adhesion and storage stability of the paint.
Here, in the present specification, the number of equivalents of the carbodiimide group means a molar mass per one carbodiimide group (-N = C = N-). Assuming that the molecular weight of the compound is M and the number of carbodiimide groups contained in one molecule of the compound is ν, the carbodiimide group equivalent is represented by M / ν, and the isocyanate group of the raw material is reacted to become a carbodiimide group It is a theoretical value obtained by assuming.

  The weight average molecular weight of the component (C) is preferably in the range of 500 to 10,000, more preferably 1,000 to 5,000, from the viewpoint of the adhesion of the coating.

  The blend ratio of the component (C) is 1 to 30 parts by mass with respect to 100 parts by mass of the component (A). From the viewpoint of adhesion, it is preferably in the range of 2 to 30 parts by mass, more preferably 4 to 20 parts by mass, and particularly preferably 5 to 15 parts by mass.

  The coating composition of the present invention is excellent in long-term storage stability of the coating by using a silane coupling agent (C) containing one or more carbodiimide groups in the molecule, and is coated after being stored for a long time Even when the film is formed, the effect of being extremely excellent in the adhesion to the object to be coated and the conductivity is exhibited.

  This is because, by having a carbodiimide group and a hydrolyzable silyl group and / or a silanol group in the same molecule, the adhesive functional group of the hydrolyzable silyl group and / or silanol group is self-condensed even during long-term storage, etc. It is believed that the resin does not easily cause deactivation due to the reaction and that the carbodiimide group is not easily affected by adsorption to a conductivity imparting agent and the like, so that excellent adhesion and conductivity can be maintained even after long-term storage.

(D) Crosslinking Agent The coating composition of the present invention may further contain a crosslinking agent, if necessary. The crosslinking agent can be used without particular limitation as long as it is a compound which can be cured by reacting with the hydroxyl group of the component (A). For example, polyisocyanate compounds (including blocked ones), melamine resins, guanamine resins And amino resins such as urea resin can be used as the crosslinking agent. From the viewpoint of obtaining a coating film excellent by weather resistance, coating film hardness, adhesion, etc., polyisocyanate compounds and / or melamine resins are preferable.

  The polyisocyanate compound is a compound having at least two isocyanate groups in one molecule, and examples thereof include aliphatic polyisocyanates, alicyclic polyisocyanates, araliphatic polyisocyanates, aromatic polyisocyanates, and said polyisocyanates. Derivatives and the like can be mentioned.

  Examples of the aliphatic polyisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, and the like. -Aliphatic diisocyanates such as butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, dimer acid diisocyanate, methyl 2,6-diisocyanatohexanoate (conventional name: lysine diisocyanate); 2 2,6-diisocyanatohexanoate 2-isocyanatoethyl, 1,6-diisocyanato-3-isocyanatomethylhexane, 1,4,8-triisocyanatooctane, 1,6, 1-triisocyanatoundecane, 1,8-diisocyanato-4-isocyanatomethyloctane, 1,3,6-triisocyanatohexane, 2,5,7-trimethyl-1,8-diisocyanato-5-isocyanatomethyl Aliphatic triisocyanates such as octane can be mentioned.

  Examples of the alicyclic polyisocyanate include 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (common name) : Isophorone diisocyanate), 4-methyl-1,3-cyclohexylene diisocyanate (conventional name: hydrogenated TDI), 2-methyl-1,3-cyclohexylene diisocyanate, 1,3- or 1,4-bis (isocyanate) Methyl) cyclohexane (conventional name: hydrogenated xylylene diisocyanate) or a mixture thereof, alicyclic bisisocyne such as methylenebis (4,1-cyclohexanediyl) diisocyanate (conventional name: hydrogenated MDI), norbornane diisocyanate, etc. 1,3,5-triisocyanatocyclohexane, 1,3,5-trimethylisocyanatocyclohexane, 2- (3-isocyanatopropyl) -2,5-di (isocyanatomethyl) -bicyclo (2.2) 1) Heptane, 2- (3-isocyanatopropyl) -2,6-di (isocyanatomethyl) -bicyclo (2.2.1) heptane, 3- (3-isocyanatopropyl) -2,5- Di (isocyanatomethyl) -bicyclo (2.2.1) heptane, 5- (2-isocyanatoethyl) -2-isocyanatomethyl-3- (3-isocyanatopropyl) -bicyclo (2.2.1 ) Heptane, 6- (2-isocyanatoethyl) -2-isocyanatomethyl-3- (3-isocyanatopropyl) -bicyclo (2.2.1) heptane, 5- (2-isocyanate) Toethyl) -2-isocyanatomethyl-2- (3-isocyanatopropyl) -bicyclo (2.2.1) -heptane, 6- (2-isocyanatoethyl) -2-isocyanatomethyl-2- (3 And-cycloaliphatic triisocyanates such as -isocyanatopropyl) -bicyclo (2.2.1) heptane and the like can be mentioned.

  Examples of the aromatic polyisocyanate include methylene bis (1,4-phenylene) diisocyanate (common name: MDI), 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, ω, ω′-diisocyanato-1 2,4-diethylbenzene, 1,3- or 1,4-bis (1-isocyanato-1-methylethyl) benzene (common name: tetramethyl xylylene diisocyanate) or a mixture thereof, m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, 2,4-tolylene diisocyanate (common name: 2,4-TDI) or 2,6-tolylene diisocyanate (common name: 2,6-TDI) Or a mixture thereof, 4,4'-to Aromatic diisocyanates such as leugin diisocyanate, 4,4'-diphenylether diisocyanate; 1,3,5-triisocyanatomethylbenzene, triphenylmethane-4,4 ', 4' '-triisocyanate, 1,3,5 -Aromatic triisocyanates such as triisocyanatobenzene, 2,4,6-triisocyanatotoluene; aromatic tetraisocyanates such as 4,4'-diphenylmethane-2,2 ', 5,5'-tetraisocyanate etc. It can be mentioned.

  Moreover, as the derivatives of the polyisocyanate, for example, dimers, trimers, biurets, allophanates, uretimines, isocyanurates, oxadiazinetriones, polymethylene polyphenyl polyisocyanates (crude MDI, polymeric MDI) of the polyisocyanate described above. And crude TDI.

  The said polyisocyanate compound may be used individually by 1 type, respectively, and may use 2 or more types together. Among these polyisocyanates, aliphatic diisocyanates, alicyclic diisocyanates and their derivatives are preferable.

  In addition, as the polyisocyanate compound, a prepolymer obtained by reacting the above polyisocyanate and a derivative thereof with a compound capable of reacting with the polyisocyanate under the condition of an excess of isocyanate group may be used. Examples of the compound capable of reacting with the polyisocyanate include compounds having an active hydrogen group such as a hydroxyl group or an amino group, and specific examples thereof include polyhydric alcohols, low molecular weight polyester resins, amines, water and the like. It can be used.

  Further, as the polyisocyanate compound, a polymer of an isocyanate group-containing polymerizable unsaturated monomer, or the isocyanate group-containing polymerizable unsaturated monomer and a polymerizable unsaturated monomer other than the isocyanate group-containing polymerizable unsaturated monomer Copolymers may be used.

  As an example of the typical commercial item of the polyisocyanate compound which has the said free isocyanate group, Burnoc D-750, -800, DN-950, -970 or 15-455 (above, brand name, DIC Corporation make) , Sumidul N3300 or N3390 (all trade names, manufactured by Sumitomo Bayer Urethane Co., Ltd.), Duranate 24A-100, TPA-100, TLA-100, P301-75E "(all trade names, manufactured by Asahi Kasei Corporation), etc. Be

  The isocyanate group of the polyisocyanate compound may be blocked, and as the polyisocyanate compound having a blocked isocyanate group, the above-mentioned polyisocyanate compound having a free isocyanate group is a phenol compound; a lactam compound; an alcohol compound; an oxime compound Mercaptan compounds; dimethyl malonate; active methylene compounds such as diethyl malonate and the like, and those blocked with known blocking agents. As an example of these typical commercial items, Bernock D-550 (trade name, manufactured by DIC Corporation), Duranate SBN-70 (trade name, manufactured by Asahi Kasei Corporation), and the like can be mentioned.

  As a melamine resin, the melamine resin which etherified the methylol group of methylolated melamine with C1-C8 monohydric alcohol can be used preferably, for example. The etherified melamine resin may be one in which all methylol groups of methylolated melamine are etherified, or one in which ether groups are partially etherified and methylol groups and imino groups remain.

  Specific examples of the etherified melamine resin include, for example, alkyl etherified melamines such as methyl etherified melamine, ethyl etherified melamine and butyl etherified melamine. The etherified melamine resins may be used alone or in combination of two or more.

  As a commercial item of the above-mentioned melamine resin, butylated melamine resin (The Mitsui Chemicals Co., Ltd. make; Yuvan 20SE-60, Euban 225, the DIC Corporation make; Super Beckamine G840, Super Beckamine G821 etc.), methylated melamine, for example Resins (Nippon Cytech Industries Ltd .; Saimel 303, Sumitomo Chemical Co., Ltd .; Sumimar M-100, Sumimar M-40S, etc.), Methyl Etherified Melamine Resins (Nippon Cytech Industries, Inc .; Simel 303, Saimel 325, Saimel 327, Saimel 350, Saimel 370, Sumimar M55 manufactured by Sumitomo Chemical Co., Ltd., methylated and butylated mixed etherified melamine resin (Nippon Cytec Industries; Ltd .; Saimel 253, Saimel 202, Saimel 2 8. Melamine resin such as Saimel 254, Saimel 272, Saimel 1130, Sumitomo Chemical Co., Ltd .; Sumimar M 66B etc.), methylated, isobutylated mixed etherified melamine resin (Nippon Cytec Industries; Saimel XV 805 etc) can be used . As a crosslinking agent, it can be used individually or in combination of 2 or more types.

  As the guanamine resin and the urea resin, methylolated amino resin obtained by the reaction of an amino component which is respectively guanamine and urea with an aldehyde, or a part or all of this methylol group is a monohydric alcohol having 1 to 8 carbon atoms. -Terylated moieties or fully etherified amino resins can preferably be used.

  When the crosslinking agent (D) is used, the compounding ratio may be appropriately blended so that the coating film is cured and has sufficient performance, but from the viewpoint of the curability of the obtained coating film, the hydroxyl group-containing resin ( The ratio of A) / crosslinking agent (D) is preferably in the range of 90/10 to 40/60, particularly 80/20 to 50/50 in mass ratio.

  When using a polyisocyanate compound as the crosslinking agent (D), the blending ratio is usually 0.5 to 2 as the equivalent ratio (NCO / OH) of the isocyanate group of the polyisocyanate compound to the hydroxyl group of the component (A). In particular, the range of 0.7 to 1.9 is preferable.

(E) Cellulose Derivative The paint composition of the present invention may contain a cellulose derivative (E), if necessary, from the viewpoint of the drying property, conductivity and the like of the obtained coating film. By blending the cellulose derivative (E), the drying property and the conductivity can be improved.

  The cellulose derivative used in the present invention is a compound containing cellulose as a constituent unit, and, for example, an esterified product of cellulose obtained by esterifying a hydroxyl group of cellulose with an acid such as a fatty acid or nitric acid, an esterified product of the cellulose Examples thereof include copolymers obtained by reacting a polymerizable unsaturated group-containing cellulose ester obtained by introducing a saturated group with another polymerizable unsaturated monomer. Examples of the esterified product of cellulose include nitrocellulose, cellulose acetate butyrate, cellulose acetate, cellulose acetate propionate and the like. Among these, cellulose acetate butyrate can be suitably used.

  Cellulose acetate butyrate (hereinafter sometimes abbreviated as CAB) is obtained by further butyl esterifying a partially acetylated product of cellulose, preferably having an acetyl group content of generally 1 to 30 parts by mass in triester However, resins having a butyryl group content of 16 to 60 parts by mass and a hydroxyl group content of 4 to 5 parts by weight of anhydrous glucose are generally commercially available. The viscosity is generally from 0.005 to 50 seconds, preferably from 0.005 to 25 seconds, as measured by the method described in ASTM-D-1343154. Specifically, for example, "CAB-381-0.5", "CAB-381-20", "CAB-381-0.1", "CAB-381-2.0", "CAB-500-5" And “CAB-551-0.2” (trade names of Eastman Chemical Products, Inc., USA). The numbers indicated by the above trade names are "CAB-[butyryl group content (parts by mass) up to the second digit of the numbers in the first half, hydroxyl amount (parts by mass) at the third digit]-falling ball viscosity of solution Indicates

  In the coating composition of the present invention, when the cellulose derivative (E) is used, the blending ratio thereof is usually 0.1 to 80 parts by mass, preferably 15 to 70 parts by mass with respect to 100 parts by mass of the component (A). More preferably, it can set suitably in the range of 20-60 mass parts.

(F) Coloring component The coating composition of the present invention can contain a coloring component (F), if necessary. The coloring component (F) in the coating composition of the present invention is a coloring component other than the conductivity imparting agent (B), and is a coloring pigment, a luster pigment and a coloring dye which are known in the field of the coating material. Two or more can be mixed and used.

  Color pigments include, for example, titanium oxide, zinc flower, carbon black, iron oxide, molybdenum red, Prussian blue, cobalt blue, azo pigments, phthalocyanine pigments, quinacridone pigments, isoindoline pigments, graphene pigments, perylene pigments And pigments such as dioxazine pigments and diketopyrrolopyrrole pigments.

  As the glitter pigment, metal flake powder such as aluminum, paste, pearl powder, graphite, glitter pigment such as MIO, etc. may be mentioned as a typical example. Examples of the metal flake powder include aluminum flakes, copper flakes, stainless steel flakes, brass flakes and chromium flakes, and examples of the mica powder include pearl mica, colored pearl mica and the like.

  These coloring components may be added directly to the coating composition, or may be mixed with a dispersing agent and a dispersing resin, dispersed and pasted, and then incorporated into the coating. The dispersant, the dispersing resin and the dispersing method may be known ones. These coloring components (F) can be used singly or in combination of two or more.

  In the coating composition of the present invention, when the coloring component (F) is used, the mixing ratio thereof is usually 1 to 500 parts by mass, preferably 2 to 300 parts by mass with respect to 100 parts by mass of the hydroxyl group-containing resin (A). It can set suitably in a part, more preferably 3 to 200 mass parts.

(G) Dehydrating agent The coating composition of the present invention may further contain a dehydrating agent (G) as needed from the viewpoint of the storage stability of the coating. As the dehydrating agent (G), dehydrating agents known per se can be used, and the following can be mentioned as typical examples thereof. (1) powdery porous metal oxide or carbonized material; for example, synthetic silica, activated alumina, zeolite, activated carbon etc., (2) composition of CaSO ₄ , CaSO ₄ · 1⁄2H ₂ O, CaO etc. Calcium compounds having: for example, calcined gypsum, soluble gypsum, quicklime etc., (3) organic alkoxy compounds; eg methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate, isopropyl orthoacetate, dimethoxypropane etc And (4) monofunctional isocyanates; for example, Additive TI (manufactured by Sumitomo Bayer Urethane Co., Ltd., trade name) and the like. These dehydrating agents can be used alone or in combination of two or more.

  The amount of the dehydrating agent (G) used varies depending on the amount of water contained in the coating composition and the absorption, adsorption capacity or reactivity with water of the dehydrating agent. From the viewpoint of storage stability, coating film performance, etc., generally 2 to 30 parts by mass, further 4 to 20 parts by mass, particularly 5 to 15 parts by mass, based on the total solid content of the coating composition Is appropriate.

  The coating composition of the present invention may further contain other resins other than the above-mentioned hydroxyl group-containing resin (A) and the cellulose derivative (E), as necessary.

  As other resins, those known as paint resins can be used. For example, acrylic resin, alkyd resin, polyester resin, vinyl resin, polyolefin resin, chlorinated polyolefin resin, polyurethane resin, epoxy resin, polyamide resin, etc. are suitable. can give.

  The resin other than the hydroxyl group-containing resin (A) can be contained as long as the coating film performance is not impaired. The compounding ratio is based on the total amount of resin solid content of the hydroxyl group-containing resin (A) And 30 parts by mass or less are preferable.

  The coating composition of the present invention may further contain, if necessary, a curing catalyst, an extender pigment (talc, clay, kaolin, barita, barium sulfate, barium carbonate, calcium carbonate, silica, alumina white, etc.), an ultraviolet absorber (eg benzo) Triazole-based absorbents, triazine-based absorbents, salicylic acid derivative-based absorbents, benzophenone-based absorbents, etc., light stabilizers (eg, hindered piperidines etc.), thickeners, antifoaming agents, plasticizers, rust inhibitors Common paint additives such as chelating agents (acetylacetone etc.), organic solvents, surface conditioners, anti-settling agents, etc. can be contained singly or in combination of two or more.

  The form of the coating composition of the present invention is not particularly limited, but from the viewpoint of storage stability, an organic solvent type coating or a non-solvent type coating is preferable. The organic solvent type is a paint which contains substantially no water as a solvent, or all or most of the solvent is an organic solvent. In particular, organic solvent-type paints are preferred from the viewpoint of coating workability.

  Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; ethyl acetate, butyl acetate, methyl benzoate, ethyl ethoxypropionate, ethyl propionate, methyl propionate and the like; tetrahydrofuran, dioxane, Ethers such as dimethoxyethane; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, glycol ethers such as 3-methoxybutyl acetate; aromatic hydrocarbons, aliphatic hydrocarbons Etc. The organic solvent is not particularly limited and can be used, but it is preferable not to contain toluene, xylene and the like from the viewpoint of the influence on the human body or the environment.

  The organic solvents can be used in combination as appropriate depending on the purpose such as adjustment of viscosity and adjustment of coating property.

  The solid content of the coating composition of the present invention is adjusted to have a solid content of at least 15 parts by mass, preferably 35 to 90 parts by mass, so that the coating workability and the amount of the organic solvent discharged can be discharged. It is preferable from the point of reduction.

  In the present specification, solid content means a residue from which volatile components are removed, and the residue may be solid or liquid at normal temperature. The solid content mass can be calculated by setting the ratio of the residual mass after drying to the mass before drying as the solid content and multiplying the solid content by the sample mass before drying. Drying conditions at the time of obtaining the solid content can be, for example, 105 ° C. for 3 hours.

  The paint composition of the present invention may be a one-pack paint or a multi-pack paint such as a two-pack paint.

  When a polyisocyanate compound is used as the crosslinking agent (D) in the coating composition of the present invention, the hydroxyl group-containing resin (A) and the conductivity imparting agent (B) from the viewpoint of storage stability and coating workability. It is preferable to use a two-component paint consisting of a main ingredient containing the above and a crosslinking agent containing the polyisocyanate compound (D), and it is preferable to use the two as a mixture just before use, the above dehydrating agent (G) and organic solvents Various additives such as solvents such as pigment dispersants, anti-settling agents, antifoaming agents, antifoaming agents, antioxidants, UV absorbers, etc. can be appropriately contained in either the main agent or the crosslinking agent. In particular, the coupling agent (C) can be added to either the main agent or the crosslinking agent, but is preferably added to the main agent from the viewpoint of storage stability. The cellulose derivative (E) and the coloring component (F) can be blended into either of the main component and the crosslinking agent, but are preferably blended into the main component from the viewpoint of storage stability.

Coating Method The coating composition of the present invention can be coated on a substrate to obtain a coated article.

The objects to be coated are not particularly limited, and metal materials; various plastic materials; inorganic materials such as glass, cement, concrete, etc .; wood; fiber materials (paper, cloth, etc.), etc. Although a composite material may be used, a non-conductive material (a material having a surface resistance value of 1 × 10 ⁷ Ω / □ or more) is preferable because the coating composition of the present invention imparts conductivity.

  Plastic materials include polyolefin resins such as polyethylene resin and polypropylene resin; polyester resins such as polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate / isophthalate; styrene-butadiene block copolymer, styrene-acrylonitrile, acrylonitrile-butadiene- Styrene resin such as styrene, polystyrene, acrylonitrile-styrene-acrylate, polyamide resin such as nylon 6, nylon 6, 6, nylon 6, 10, metaxylylene adipamide, acrylic such as polymethyl methacrylate, methyl methacrylate, ethyl acrylate Resin; polyvinyl chloride resin, vinylidene chloride resin such as vinyl chloride-vinyl acetate, unsaturated polyester resin, Phenol resins, melamine resins, urea resins, polyphenylene ether resins, polyoxymethylene resins, polyurethane resins, plastic materials of the resin and various fiber-reinforced plastic (FRP) such as an epoxy resin. The plastic substrate may be a hybrid resin of two or more resins.

  Degreasing treatment, surface treatment, etc. can be appropriately carried out according to these objects to be coated.

  The coating method of the coating composition of the present invention on the object to be coated is not particularly limited. For example, dip coating after immersion coating, flow coating after coating, spray coating, airless spray, brush coating, roller, roll It can carry out using coater coating etc.

  The curing conditions of the coating composition of the present invention can be appropriately selected from baking conditions under which the coating is cured, but the temperature is in the range of room temperature (25 ° C.) to 160 ° C., particularly 40 ° C. to 140 ° C. The baking time is preferably in the range of 30 seconds to 60 minutes, particularly 1 to 40 minutes. Moreover, the coating film thickness in that case is 3-50 micrometers in dry coating film thickness, and the inside of the range of 8-30 micrometers is especially suitable.

Method of Forming Coating Film After forming a coating film with the coating composition of the present invention, a top coating may be applied.

  Specifically, the coating composition of the present invention is applied to the above-mentioned to-be-coated article to form an undercoat film, and a top coat composition is applied onto the undercoat film to form a top coat film. A coating film forming method including the step of

  Before applying the topcoat composition, the coating film of the coating composition of the present invention may be cured or uncured. In addition, the coating composition of the present invention may be applied in an uncured state, and the undercoat layer and the top coat may be simultaneously cured by heating or the like.

  In the present invention, the cured coating means the cured and dried state defined in JIS K 5600-1-1, that is, the center of the coated surface is strongly sandwiched between the thumb and the index finger, and dents due to fingerprints are formed on the coated surface. No coating movement was felt, and the center of the coated surface was rapidly and repeatedly rubbed with a fingertip, and the coated surface was not scratched. On the other hand, the uncured coating film is a state in which the coating film has not reached the above-mentioned cured and dried state, and also includes a touch-dried state and a semi-cured dried state defined in JIS K 5600-1-1.

  The paint of the present invention is applied, and if necessary, the uncured undercoat film obtained is not dried or dried to an extent not substantially cured by means such as preheating or air blowing. The solid content may be adjusted to an extent. The heating can be performed by a known heating means, and for example, a drying furnace such as a hot air furnace, an electric furnace, an infrared induction heating furnace, or the like can be used.

  The above-mentioned preheating is generally carried out at a temperature of 30 to 110 ° C., preferably 40 to 90 ° C., more preferably 50 to 70 ° C., for 30 seconds to 20 minutes in a drying oven. It can be carried out by heating directly or indirectly, preferably for 1 to 15 minutes, more preferably for 2 to 10 minutes, and the air blowing is usually performed at normal temperature or about 25 ° C. to the coated surface of the substrate. It can be carried out by blowing air heated to a temperature of about 80 ° C. for about 30 seconds to about 15 minutes.

  As the top coat, those known per se can be used. Specifically, clear paint such as acrylic resin and melamine resin type, acrylic resin and (block) polyisocyanate compound type, solid color paint containing metallic pigment etc. in the above resin type, metallic paint, light interference paint, etc. Can be mentioned. The form of these top coats is not particularly limited, and examples thereof include an organic solvent type, an aqueous solution type, an aqueous dispersion type, a high solid type, etc., and the coated film is dried and cured by room temperature, heating, active energy ray irradiation, etc. be able to. The top coat may be a single layer or a multilayer of two or more layers.

  Among them, the top coat composition preferably contains a hydroxyl group-containing resin and a crosslinking agent from the viewpoint of adhesion to a coating film obtained by applying the coating composition of the present invention, and in particular, weather resistance and water resistance From the viewpoint of finish and finish, those containing a hydroxyl group-containing acrylic resin and a (optionally blocked) polyisocyanate compound are preferable.

  The hydroxyl group-containing acrylic resin is usually prepared by copolymerizing a hydroxyl group-containing polymerizable unsaturated monomer and another polymerizable unsaturated monomer copolymerizable with the hydroxyl group-containing polymerizable unsaturated monomer by a method known per se It can be manufactured. As the hydroxyl group-containing polymerizable unsaturated monomer and the other polymerizable unsaturated monomer, those mentioned in the paragraph of the hydroxyl group-containing resin (A) can be used.

  The hydroxyl group-containing acrylic resin used for the topcoating composition preferably has a hydroxyl value of 5 to 160 mg KOH / g, particularly preferably 24 to 130 mg KOH / g, and the designability, weatherability, etc. of the obtained coating film From the point of point of view, the weight average molecular weight is preferably in the range of 5,000 to 100,000, particularly preferably 10,000 to 70,000.

  As the polyisocyanate compound (which may be blocked), those mentioned in the section of the crosslinking agent (D) can be suitably used. The said polyisocyanate compound may be used individually by 1 type, respectively, and may use 2 or more types together. Among these polyisocyanates, aliphatic diisocyanates, alicyclic diisocyanates and their derivatives are preferable from the viewpoint of weatherability.

  The top coat composition further includes pigments such as color pigments and extender pigments, non-water dispersion resins, polymer fine particles, curing catalysts, organic solvents, ultraviolet absorbers, light stabilizers, antioxidants, surface conditioners, and pigments. Additives for paints such as dispersants and curing catalysts can be appropriately combined and blended.

  The curing conditions for the top coating can be appropriately selected from the baking conditions under which the coating is cured, but the curing temperature is preferably in the range of room temperature (25 ° C.) to 160 ° C., more preferably 40 ° C. to 140 ° C. . The baking time is preferably in the range of 30 seconds to 60 minutes, more preferably 1 to 40 minutes. Moreover, the coating film thickness in that case is preferably in a range of 3 to 100 μm, more preferably 8 to 80 μm, in terms of dry coating thickness.

  The coating composition of the present invention is excellent in adhesion to a substrate and a topcoating film even when the coating composition is used after long-term storage to form a coating film.

  Although the coating composition of the present invention is not particularly limited, it can be applied as a conductive primer, an antistatic coating of various plastic materials, and a highly conductive coating depending on the surface resistance value of the resulting cured coating film.

  Hereinafter, the present invention will be described in more detail by way of examples. In addition, "part" and "%" show "mass part" and "mass%", unless it mentions specially.

(Production Example 1)
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a dropping device, 20 parts of butyl acetate and 30 parts of methoxypropyl acetate are charged and stirred at 115 ° C. while blowing in nitrogen gas.
21.0 parts of 2-hydroxyethyl acrylate,
Plaxcel FM3 (Note 1) 23.1 (solid content 18.5 parts),
5.0 parts of styrene,
50.0 parts of methyl methacrylate,
5.0 parts of n-butyl acrylate,
0.5 parts of acrylic acid,
Then, a mixture of 1.0 part of 2,2'-azobisisobutyronitrile (polymerization initiator) was dropped at a uniform speed over 3 hours, and then aged for 2 hours at the same temperature.
Thereafter, a mixture of 10 parts of butyl acetate and 0.2 parts of 2,2'-azobisisobutyronitrile is further dropped into the reaction vessel over 1 hour, and after completion of the dropping, it is aged for 1 hour, and swasol 1500 (Note 2). It was diluted with 45.5 parts to obtain a 50% solids hydroxyl group-containing resin No. 1 solution was obtained. The acid value of the obtained resin solid content was 3.9 mg KOH / g, the hydroxyl value was 123 mg KOH / g, and the weight average molecular weight was 40,000.

(Production Examples 2 to 4)
In Production Example 1, the same procedure as in Production Example 1 was carried out except that the monomer to be blended, the organic solvent, the polymerization initiator, and the reaction temperature were as shown in Table 1, and hydroxyl group-containing resin No. 2-No. I got four.
The solid content, acid value, hydroxyl value and weight average molecular weight of each hydroxyl group-containing resin are shown in Table 1.

  (Note 1) Plaxcel FM3: trade name, manufactured by Daicel Chemical Industries, Ltd., a xylene-diluted product of an ε-caprolactone 3 mol adduct of 2-hydroxyethyl methacrylate, solid content 80%.

  (Note 2) Swazole 1500: trade name, manufactured by Maruzen Petrochemical Co., Ltd., aromatic hydrocarbon solvent.

(Production Example 5)
The components (33.2 parts of isophthalic acid, 52.4 parts of hexahydrophthalic anhydride, 52.5 parts of adipic acid) were added to a reactor equipped with a heating device, a thermometer, a stirrer, a rectification column, and a reflux condenser attached with a water separator. 6 parts, 33.5 parts of trimethylolpropane and 94.4 parts of 1,6-hexanediol were charged and heated, and the temperature was raised from 160 ° C. to 230 ° C. over 3 hours.
This is maintained at 230 ° C. for 1 hour, xylene is added, and condensed water is distilled off using a rectification column while refluxing at the same temperature for about 6 hours. Two hours after addition of xylene, measurement of the acid value was started, and the reaction was terminated when the acid value became 2 or less. After completion of the reaction, the volatile component is distilled off under reduced pressure, and solvent substitution and dilution are performed with swasol 1500 (note 2) / butyl acetate = 70/30 to obtain hydroxyl group-containing resin No. 5 solutions were obtained. The resin No. The weight average molecular weight of 5 was 5,300, and the hydroxyl value was 86 mg KOH / g.

Example 1
Hydroxyl group containing resin No. Mix 200 parts of 1 solution (100 parts of solid content), 100 parts of VULCAN XC-72 (Note 3), 50 parts of Flowlen NC-500 (Note 6) (15 parts of solid content), and 387 parts of butyl acetate, and use a sand mill. Dispersion was performed to obtain a dispersion paste. The resulting dispersion paste was mixed with 30 parts of XL-701 (15 parts of solid content), 25 parts of CAB 551-0.2 (Note 11) (25 parts of solid content) and 20 parts of MOA (Note 14). By adding butyl acetate so as to be 30% and stirring, paint composition No. 1 is prepared. I got one. The resulting paint composition no. For 1), the storage stability (Note 15) of the paint was tested. Table 2 shows the evaluation results.

  In addition, paint composition No. 1 1 and hydroxyl group-containing resin No. 1 An SMC molded plate (coated material: DIC mat 1300, a coating prepared by adding 35 parts of duranate TLA-100 (Note 16) as a crosslinking agent to 100 parts of one solid content and adjusting the solid content to 25% with butyl acetate. The product name, made by DIC Chemical Industries, was molded at 140 ° C to a thickness of 5 mm and cut into a size of 100 mm × 150 mm) by air spray coating to a dry film thickness of 20 μm, and set for 5 minutes at normal temperature Thereafter, it was baked at 80 ° C. for 30 minutes to obtain a coated plate. The coated plate thus obtained was allowed to stand for 24 hours in an atmosphere of 23 ° C. and 50% relative humidity as a test plate, and the surface resistance value (Note 17) was measured. Table 2 shows the evaluation results.

(Examples 2 to 24, Comparative Examples 1 to 6)
Coating composition No. 1 was prepared in the same manner as in Example 1 except that the composition of each component was changed to that shown in Table 2 in Example 1. 2-No. 24 and Comparative Examples 1 to 6 were obtained. In addition, the compounding quantity of Table 2 shows the compounding quantity of solid content. The notes in Example 1 and Table 2 have the following meanings.

(Note 3) VULCAN XC-72: trade name, manufactured by CABOT, conductive carbon black,
(Note 4) Ketjen Black EC 600 JD: trade name, manufactured by Lion Corporation, conductive carbon black, DBP oil absorption amount 495 ml / 100 g,
(Note 5) HCA-1: trade name, manufactured by NOVAMET, scaly nickel (nickel flakes), average particle diameter 10 μm.

(Note 6) FLORENE NC-500: trade name, manufactured by Kyoeisha Chemical Co., Ltd., pigment dispersant containing no acid group / basic group, 50% active ingredient (propylene glycol monomethyl ether acetate solution),
(Note 7) DISPER BYK-161: trade name, manufactured by Big Chemie Co., Ltd., pigment wetting and dispersing agent, solid content 30% (methoxypropyl acetate: butyl acetate = 6: 1 solution), amine value 11 mg KOH / g,
(Note 8) DISPER BYK-2000: trade name, manufactured by Big Chemie Co., Ltd., pigment wetting and dispersing agent, solid content 40% (methoxypropyl acetate: butyl alcohol = 1: 1 solution), amine value 4 mg KOH / g.

(Note 9) XL-701: trade name, manufactured by Picachan, carbodiimide group-containing silane coupling agent, active ingredient = 50% by mass, carbodiimide equivalent = 590,
(Note 10) XL-725: trade name, manufactured by Picachan Corporation, carbodiimide group-containing silane coupling agent, active ingredient = 100% by mass, carbodiimide equivalent = 700.

(Note 11) CAB-551-0.2: trade name, manufactured by Eastman Chemical Products, cellulose acetate butyrate,
(Note 12) CAB-381-2: trade name, manufactured by Eastman Chemical Products, cellulose acetate butyrate.

  (Note 13) Dibutyltin dilaurate: Urethane curing catalyst, solid content = 100% by mass.

  (Note 14) MOA: trade name, manufactured by Nichiho Kagaku Co., Ltd., dehydrating agent, active ingredient ortho acetic acid methyl ester.

(Note 15) Storage stability: 200g of each coating composition before blending the cross-linking agent in a 1 / 4L capacity inner coat can, seal tightly and store for 30 days in 40 ° C constant temperature room or 25 ° C constant temperature room respectively After cooling to room temperature (about 20 ° C.), the container was opened and the condition in the container was evaluated based on the following criteria.
S: It is in the initial state, there is no change,
A: Slightly thickened (homogenized by hand stirring),
B: Remarkable sedimentation or occurrence of lumps, or thickening C: Significant thickening (impossible to coat).

  (Note 16) Duranate TLA-100: trade name, manufactured by Asahi Kasei Chemicals Corporation, isocyanurate of hexamethylene diisocyanate, solid content 100% by mass, NCO content 23.5%.

(Note 17) Adhesion:
100 pieces of 2 mm × 2 mm goban eyes are made on the coating according to JIS K 5600-5-6 (1990) on each coated surface, adhesive tape is attached to that surface, and after it is peeled off rapidly, on the coated surface The number of remaining goblet coatings was evaluated.
S: Remaining number / total number = 100 pieces / 100 pieces without edge chipping A: Remaining number / total number = 100 particles / 100 with edge chippings B: Remaining number / total number = 99 pieces / 90 pieces / 100 pieces C: Remaining number / total number = 89 or less / 100.

(Note 18) Surface resistance:
The surface resistance value of each test plate was measured using Lorester GP (four-point probe method) manufactured by Mitsubishi Chemical Analytic. The measurement results were evaluated according to the following criteria.
3: The surface resistance of the coating is less than 1 × 10 ³ Ω / □,
2: The surface resistance value of the coating is 1 × 10 ³ or more and 1 × 10 ⁷ Ω / □ or less
1: The surface resistance value of the coating film is 1 × 10 ⁷ Ω / □ or more.

"---" in Table 2 indicates that the coating composition could not be coated because the coating composition was significantly thickened.

(Example 25)
Coating composition No. 1 obtained in Example 1 No. 1, hydroxyl group-containing resin No. 1 35 parts of Duranate TLA-100 (Note 16) as a cross-linking agent was added to 100 parts of one solid content, and the solid content was adjusted to 25% with butyl acetate. I got 31. The resulting paint composition no. No. 31 was air-spray coated on the coated material SMC to a dry film thickness of 20 μm, set for 5 minutes at normal temperature, and then baked for 30 minutes at 80 ° C. Thereafter, air-spray coating is applied on the top-coat paint type (1) (note 21) shown in Table 3 to a dry film thickness of 70 μm, and set for 5 minutes at normal temperature, then heat cured at 80 ° C. for 30 minutes, I got
In addition, paint composition No. 1 obtained in Example 1 after storage (1 month at 25 ° C. and 1 month at 40 ° C.). The preparation and coating were performed in the same manner as above using 1 to obtain a coated plate after storage at 25 ° C. for 1 month and a coated plate after storage at 40 ° C. for 1 month. The obtained initial, after 1 month storage at 25 ° C. and after 1 month storage at 40 ° C. were allowed to stand under an atmosphere of 23 ° C. and 50% relative humidity for 24 hours and used as test plates for various tests. The test results are shown in Table 3.

(Examples 26 to 54, Comparative Examples 7 to 12)
Coating composition No. 1 was prepared in the same manner as in Example 25 except that the ingredients shown in Table 3 were blended. 31 to No. 60 and Comparative Example compositions 61 to 66 were obtained. In addition, the compounding quantity of Table 3 shows the compounding quantity of solid content. The obtained initial, after 1 month storage at 25 ° C. and after 1 month storage at 40 ° C. were allowed to stand under an atmosphere of 23 ° C. and 50% relative humidity for 24 hours and used as test plates for various tests. The test results are shown in Table 3.

  (Note) in Example 25 and Table 3 has the following meaning.

  (Note 19) Yuvan 20SE-60: trade name, manufactured by Mitsui Chemicals, Inc., n-butylated melamine resin, solid content 60 mass% (xylol: n-butanol = 4: 6 solution).

(Note 20) Coated product SMC: SMC molded plate, DIC mat 1300 (trade name, manufactured by DIC Chemical Industries, Ltd.) molded at 140 ° C. to a thickness of 5 mm and cut into a size of 100 mm × 150 mm,
To-be-coated-article G-EP: A glass epoxy laminated board, Sumirito EL-3762 (a brand name, Sumitomo Bakelite Co., Ltd. make, 1.5 mm in thickness) which was cut | judged in the magnitude | size of 100 mm x 150 mm.

  (Note 21) Top coat paint type (1): Retan PG-60 white, trade name, manufactured by Kansai Paint Co., Ltd., a two-component organic solvent-type paint of hydroxyl group-containing acrylic resin / polyisocyanate curing type.

«Test method»
(Note 22) Adhesion:
100 pieces of 2 mm × 2 mm goban eyes are made on the coating according to JIS K 5600-5-6 (1990) on each coated surface, an adhesive tape is attached to the surface, and after it is peeled off sharply, the top coat is applied. The remaining number of was evaluated.
S: Remaining number / total number = 100 pieces / 100 pieces without edge chipping A: Remaining number / total number = 100 particles / 100 with edge chippings B: Remaining number / total number = 99 pieces / 90 pieces / 100 pieces C: Remaining number / total number = 89 or less / 100.

(Note 23) Water resistance:
The test boards were immersed in warm water at 40 ° C. for 240 hours, and then the appearance and adhesion of the test boards washed with water were evaluated based on the following criteria.
<Appearance (after water resistance test)>
S: No change in appearance at all with respect to the film before test A: A slight gloss, blister, whitening or discoloration is observed with respect to the film before test No level B: There is considerable glossiness, blistering, whitening or discoloration relative to the coating before the test C: Significant glossiness, swelling, whitening or discoloration relative to the coating before the test .
<Adhesion (after water resistance test)>
100 pieces of 2 mm × 2 mm goban eyes are made on the coated surface according to JIS K 5600-5-6 (1990) on the coated surface after each water resistance test, adhesive tape is attached to the surface, and it is rapidly peeled off The remaining number of top coat films was evaluated.
S: Remaining number / total number = 100 pieces / 100 pieces without edge chipping A: Remaining number / total number = 100 particles / 100 with edge chippings B: Remaining number / total number = 99 pieces / 90 pieces / 100 pieces C: Remaining number / total number = 89 or less / 100.

(Example 55)
Coating composition No. 1 obtained in Example 1 No. 1, hydroxyl group-containing resin No. 1 35 parts of Duranate TLA-100 (Note 16) as a cross-linking agent was added to 100 parts of 1 solid content, and the solid content was adjusted to 25% with butyl acetate. I got 31. The resulting paint composition no. No. 31 was air-spray coated on the coated material SMC to a dry film thickness of 20 μm, and set for 5 minutes at normal temperature. Thereafter, the top coat type (1) (Note 21) was air-spray coated to a dry film thickness of 70 μm, set for 5 minutes at normal temperature, and then heat cured at 80 ° C. for 30 minutes to obtain an initial coated plate.
In addition, paint composition No. 1 obtained in Example 1 after storage (1 month at 25 ° C. and 1 month at 40 ° C.). Preparation and coating of the coating composition for undercoating were carried out in the same manner as described above using 1 to obtain a coated plate after storage at 25 ° C. for 1 month and a coated plate after storage at 40 ° C. for 1 month. The obtained initial, after 1 month storage at 25 ° C. and after 1 month storage at 40 ° C., were left for 24 hours under an atmosphere of 23 ° C. and 50% relative humidity to serve as test plates for evaluation. The same result as Example 25 was obtained.

"---" in Table 3 indicates that the coating composition could not be coated due to remarkable thickening.

Claims (9)

A coating composition comprising (A) a hydroxyl group-containing resin having an acid value of less than 10 mg KOH / g, (B) a conductivity imparting agent, and (C) a silane coupling agent containing one or more carbodiimide groups in the molecule. The solid content of the conductivity imparting agent (B) is in the range of 25 to 500 parts by mass, based on 100 parts by mass of the resin solid content of the hydroxyl group-containing resin (A), and the silane The coating composition whose solid content of a coupling agent (C) is 1-30 mass parts.   The coating composition according to claim 1, wherein a part or all of the conductivity imparting agent (B) is a conductive carbon black.   The coating composition according to claim 1 or 2, wherein the weight average molecular weight of the silane coupling agent (C) is 500 to 10,000.   The paint composition according to any one of claims 1 to 3, wherein the number of equivalents of the carbodiimide group in the silane coupling agent (C) is 300 to 2,000.   Furthermore, the coating composition of any one of Claims 1-4 containing a crosslinking agent (D).   Furthermore, the coating material composition of any one of Claims 1-5 containing a cellulose derivative (E).   Furthermore, the coating composition of any one of Claims 1-6 containing a coloring component (F).   The coated article obtained by coating the coating composition of any one of Claims 1-7 to a to-be-coated-article.   A step of applying the coating composition according to any one of claims 1 to 7 onto a substrate to form an undercoating film, and applying an overcoating composition on the undercoating film to apply an overcoating. A method of forming a coating, comprising the step of forming a coating.