JP2006016542A - Epoxy-polyester-based powder coating composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an epoxy-polyester-based powder coating composition forming a good cured coating film at a low heating temperature and having excellent storage stability. <P>SOLUTION: The epoxy-polyester-based powder coating composition comprises an epoxy resin, a polyester resin and an inclusion compound comprising a macromolecular host compound as a host compound and a hardener and/or a hardening accelerator as a guest compound. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an epoxy / polyester powder coating composition comprising an epoxy resin, a polyester resin, and an inclusion compound containing a curing agent and / or a curing accelerator as a guest compound.

  2. Description of the Related Art Conventionally, a coating method using a powder coating for coating home appliances, building materials, automobile parts, and the like is known. Compared to conventional solvent-based paints, powder paints are environmentally friendly because they do not use solvents, the process of drying the paint film is unnecessary, and the cost of paint can be reduced by reusing recovered powder. In recent years, demand has increased because of the fact that a cured coating film having excellent mechanical strength, chemical resistance, corrosion resistance, weather resistance, and the like can be obtained.

  Examples of the powder paint include epoxy powder paint, polyester powder paint, acrylic powder paint, and epoxy / polyester powder paint. In particular, epoxy / polyester powder coatings are often used for decorative coatings such as steel furniture and home appliances because they can provide a matte-like cured coating with excellent corrosion resistance and design. .

  In the case of coating using this epoxy / polyester powder coating, the curing temperature must be set high in order to obtain a good cured coating film. For this reason, the object to be coated is limited to a material having high heat resistance such as metal. Therefore, in recent years, a method for obtaining a cured coating film at a low curing temperature using a highly active curing agent such as an alkylimidazole compound has been proposed (Patent Documents 1 and 2). However, a powder coating containing a highly active curing agent has been problematic because the curing reaction of the powder coating gradually proceeds even during storage, and the storage stability of the powder coating may deteriorate. Accordingly, there is a demand for the development of an epoxy / polyester-based powder coating composition that can obtain a good cured coating film at a low curing temperature and is excellent in storage stability.

In relation to the present invention, Patent Documents 3 and 4 propose an epoxy paint obtained by adding an inclusion compound containing a tetrakisphenol compound as a host compound and a curing agent and / or a catalyst as a guest compound to an epoxy resin. Has been.
However, neither of Patent Documents 3 and 4 specifically describes an epoxy / polyester powder coating.

JP 2002-60681 A Japanese Patent Laid-Open No. 2002-235032 Japanese Patent Laid-Open No. 10-324826 Japanese Patent Laid-Open No. 11-071449

  The present invention has been made in view of the above-described prior art, and provides an epoxy-polyester powder coating composition that can form a good cured coating film at a low heating temperature and has excellent storage stability. Is an issue.

  As a result of diligent research to solve the above problems, the present inventors have used an epoxy resin, a polyester resin, and a tetrakisphenol compound represented by the following formula (1) as a host compound, and a curing agent or a curing accelerator as a guest compound. It has been found that the powder coating composition containing the clathrate compound can form a good cured coating film at a low heating temperature and has excellent storage stability, and the present invention has been completed.

  Thus, according to the first aspect of the present invention, the inclusion compound (a) comprising (1) an epoxy resin, (2) a polyester resin, and (3) a multimolecular host compound as a host compound and a curing agent as a guest compound. An epoxy-polyester powder coating composition characterized by containing is provided.

  In the first powder coating composition of the present invention, the multimolecular host compound is preferably a compound having two or more hydroxyl groups and two or more aromatic groups in the molecule. I)

Wherein, X _{is, (CH 2)} n _(n is. Represents an integer of 0 to 3), or an even phenylene group optionally having a ^substituent, R 1 to R ⁸ are each independently And a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an optionally substituted phenyl group, a halogen atom, or an alkoxy group having 1 to 6 carbon atoms. It is more preferable that it is a tetrakisphenol compound represented by
The first powder coating composition of the present invention preferably further contains a curing accelerator.

  According to the second of the present invention, (1) an epoxy resin, (2) a polyester resin, and (4) an inclusion compound (b) having a multimolecular host compound as a host compound and a curing accelerator as a guest compound. The powder coating composition characterized by containing is provided.

In the second powder coating composition of the present invention, the multimolecular host compound is preferably a compound having two or more hydroxyl groups and two or more aromatic groups in the molecule. The tetrakisphenol compound represented by (I) is more preferable.
The second powder coating composition of the present invention preferably further contains a curing agent.
In the 1st and / or 2nd powder coating composition of this invention, it is preferable to contain 0.001-0.1 mol of said clathrate compounds with respect to 1 mol of epoxy rings of an epoxy resin.

  The epoxy-polyester-based powder coating composition of the present invention can form a good cured coating film at a low heating temperature and is excellent in storage stability.

Hereinafter, the epoxy-polyester powder coating composition of the present invention will be described in detail.
1) Epoxy / polyester powder coating composition The epoxy / polyester powder coating composition of the present invention includes the following two types.
The powder coating composition of the first invention comprises (1) an epoxy resin, (2) a polyester resin, and (3) an inclusion compound (a) having a multi-molecular host compound as a host compound and a curing agent as a guest compound (a ), And the powder coating composition of the second invention comprises (1) an epoxy resin, (2) a polyester resin, and (4) a multimolecular host compound. A clathrate compound (b) comprising a compound and a curing accelerator as a guest compound is used.

(1) Epoxy resin The epoxy resin used in the powder coating composition of the present invention is not particularly limited as long as it has at least one epoxy group in one molecule. For example, bisphenol A-epichlorohydrin resin, polyfunctional epoxy resin, alicyclic epoxy resin, brominated epoxy resin, novolac type epoxy resin, acrylic epoxy resin and the like can be mentioned. These epoxy resins can be used alone or in combination of two or more.

(2) Polyester resin The polyester resin used in the powder coating composition of the present invention is not particularly limited as long as it is a polymer having an ester bond in the main chain.

  Examples of the polyester resin include a polyalkylene terephthalate resin, a polyalkylene naphthalate resin, an unsaturated polyester resin, and an alkyd resin. These polyester resins can be used alone or in combination of two or more.

  Examples of the polyalkylene terephthalate resin include ethylene glycol, diethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, , 4-cyclohexanediol or the like and terephthalic acid or terephthalic acid ester can be obtained by polycondensation in the presence of a base catalyst or an acid catalyst. Specific examples thereof include polyethylene terephthalate and polybutylene terephthalate.

  The polyalkylene naphthalate resin can be obtained by polycondensing the glycols with naphthalene dicarboxylic acid or naphthalene dicarboxylic acid ester such as 1,8-naphthalenedicarboxylic acid in the presence of a base catalyst or an acid catalyst. Specific examples thereof include polyethylene naphthalate.

  The unsaturated polyester resin is obtained by reacting an unsaturated dicarboxylic acid such as maleic acid or fumaric acid, an ester of unsaturated carboxylic acid, or an unsaturated carboxylic acid anhydride such as phthalic anhydride or maleic anhydride with glycols. It is resin obtained by.

  Alkyd resins include polyols such as glycerin, pentaerythritol, ethylene glycol and trimethylolethane, higher fatty acids such as palmitic acid, and dibasic acids such as phthalic acid and maleic acid, or dibasic acids such as phthalic anhydride and maleic anhydride. This resin is obtained by condensing the three basic acid anhydrides. Specific examples thereof include gliptal resins.

  In the powder coating composition of the present invention, the compounding amount of the polyester resin is usually 1 to 1,000 parts by weight, preferably 10 to 500 parts by weight, more preferably 50 to 100 parts per 100 parts by weight of the epoxy resin. Parts by weight.

(3) Inclusion compound (a)
The clathrate compound (a) used in the powder coating composition of the present invention is a clathrate compound having a multimolecular host compound as a host compound and a curing agent as a guest compound.
(I) Multimolecular host compound The multimolecular host compound used in the present invention forms a crystal having an internal space in which a plurality of molecules are aggregated through hydrogen bonding or the like, and a guest is formed in the formed space. It is a compound that can include a compound.

The multimolecular host compound used in the present invention is not particularly limited as long as it is a compound having such properties.
For example, phenol, o-chlorophenol, 2,4,6-trichlorophenol, p-chlorophenol, o-nitrophenol, p-nitrophenol, 2,4-dinitrophenol, 2,6-dinitrophenol, 2,4 Compounds having one aromatic group and one hydroxyl group in the molecule, such as 1,6-trinitrophenol, pt-butylphenol, pt-octylphenol;
compounds having one aromatic group and two hydroxyl groups in the molecule, such as t-butylhydroquinone and 2,5-di-t-butylhydroquinone;

  α, α, α ′, α′-tetraphenyl-1,1′-biphenyl-2,2′-dimethanol, 4,4′-cyclohexylidene bisphenol, 4,4′-methylene bisphenol, 4,4 ′ -Ethylidenebisphenol, 5,5'-methylenedisalicylic acid, bis (4-hydroxyphenyl) sulfide, 4,4'-butylidenebis (3-methyl-6-t-butylphenol), 2,2'-methylenebis (4-methyl) -6-tert-butylphenol), 4,4 '-(1-phenylethylidene) bisphenol, 2,5-bis (2,4-dimethylphenyl) hydroquinone, 1,1,6,6-tetraphenyl-2,4 Hexadiyne-1,6-diol, 1,1,4,4-tetraphenyl-2-butyne-1,4-diol, 1,1,2,2-tetrapheny Ethane-1,2-diol, 1,1,6,6-tetrakis (2,4-dimethylphenyl) -2,4-hexadiyne-1,6-diol, 9,9′-bianthracene, 9,10 -Bis (4-methylphenyl) -9,10-dihydroanthracene-9,10-diol, 9,10-diphenyl-9,10-dihydroanthracene-9,10-diol, 1,1-bis-2-naphthol ;

  4,4′-dihydroxybenzophenone, 2,4′-dihydroxybenzophenone, 3,4′-dihydroxybenzophenone, 3,3′-dihydroxybenzophenone, 2,3′-dihydroxybenzophenone, 2,2′-dihydroxybenzophenone, 4, 4′-dihydroxy-2-methylbenzophenone, 4,4′-dihydroxy-3-methylbenzophenone, 4,4′-dihydroxy-2-chlorobenzophenone, 4,4′-dihydroxy-3-chlorobenzophenone, 4,4 ′ -Dihydroxy-2-methoxybenzophenone, 4,4'-dihydroxy-2-methoxybenzophenone, 4,4'-dihydroxy-2,2'-dimethylbenzophenone, 4,4'-dihydroxy-3,3'-dimethylbenzophenone, 4,4'-dihydro Cis-2,2′-dichlorobenzophenone, 4,4′-dihydroxy-3,3′-dichlorobenzophenone, 4,4′-dihydroxy-2,2′-dimethoxybenzophenone, 4,4′-dihydroxy-2,2 '-Dimethoxybenzophenone, 3,3'-dihydroxy-2,2'-dimethylbenzophenone, 3,3'-dihydroxy-4,4'-dimethylbenzophenone, 2,2'-dihydroxy-3,3'-dimethylbenzophenone, 2,2′-dihydroxy-4,4′-dimethylbenzophenone,

2,2 ′, 4,4′-tetrahydroxybenzophenone, 2,2 ′, 3,3′-tetrahydroxybenzophenone, 3,3 ′, 4,4′-tetrahydroxybenzophenone, 2,2 ′, 3,4 '-Tetrahydroxybenzophenone, 3,3', 2,4'-tetrahydroxybenzophenone, 4,4 ', 3,2'-tetrahydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2 ', 4,4'-tetrahydroxy-3,3'-dimethylbenzophenone, 2,2', 4,4'-tetrahydroxy-3,3'-dichlorobenzophenone, 2,2 ', 4,4'-tetra Two or more aromatic groups in the molecule, such as a hydroxybenzophenone compound such as hydroxy-3,3′-dimethoxybenzophenone; a tetrakisphenol compound represented by the formula (I); A compound having two or more hydroxyl groups; and 1,4-diazabicyclo- [2.2.2] -octane, granular corn starch (porous Y-20), 5,5-dimethylhydantoin, N-phenylmaleimide, 9 , 9′-bianthracene and other multimolecular host compounds;
These multimolecular host compounds can be used alone or in combination of two or more.

  Among these, an epoxy / polyester powder coating composition that can form a good cured coating film at a low temperature and has excellent storage stability is obtained. Therefore, two or more aromatic groups and two or more hydroxyl groups are present in the molecule. A compound having a group is preferred, a hydroxybenzophenone compound and a tetrakisphenol compound represented by the formula (I) are more preferred, and a tetrakisphenol compound represented by the formula (I) is particularly preferred.

In the formula (I), X represents (CH ₂ ) _n or a phenylene group which may have a substituent.
n represents an integer of 0 to 3, and is preferably 0.
The phenylene group may be any of a p-phenylene group, an m-phenylene group, and an o-phenylene group, but a p-phenylene group is preferable.
Examples of the substituent of the phenylene group which may have a substituent include halogen atoms such as fluorine atom, chlorine atom and bromine atom; alkyl groups such as methyl group, ethyl group and n-propyl group; methoxy group and ethoxy group And an alkoxy group such as an n-propoxy group; and the like, and preferably has no substituent.

R ^{1 to} R ⁸ are each independently a hydrogen atom; an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, or an isopropyl group; a phenyl group, a 2-chlorophenyl group, or 4-methyl. Phenyl group optionally having substituents such as phenyl group, 2,4-difluorophenyl group, 3,5-dimethoxyphenyl group, 2,4,6-trimethylphenyl group; fluorine atom, chlorine atom, bromine atom Or a C1-C6 alkoxyl group such as a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, or a t-butoxy group.

  Specific examples of the compound represented by the formula (I) include 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane (TEP), 1,1,2,2-tetrakis (3-methyl-4). -Hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3,5-dimethyl-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-chloro-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3,5-dichloro-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-bromo-4-hydroxyphenyl) ethane, 1,1,2, 2-tetrakis (3,5-dibromo-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-tert-butyl-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3,5-di-t-butyl-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-fluoro-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3 , 5-Difluoro-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-methoxy-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3,5-dimethoxy-4) -Hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-chloro-5-methyl-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-bromo-5-methyl-4) -Hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-methoxy-5-methyl-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-t-butyl- -Methyl-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-chloro-5-bromo-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis (3-chloro-5) -Phenyl-4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis [(4-hydroxy-3-phenyl) phenyl] ethane,

  1,1,3,3-tetrakis (4-hydroxyphenyl) propane, 1,1,3,3-tetrakis (3-methyl-4-hydroxyphenyl) propane, 1,1,3,3-tetrakis (3, 5-dimethyl-4-hydroxyphenyl) propane, 1,1,3,3-tetrakis (3-chloro-4-hydroxyphenyl) propane, 1,1,3,3-tetrakis (3,5-dichloro-4- Hydroxyphenyl) propane, 1,1,3,3-tetrakis (3-bromo-4-hydroxyphenyl) propane, 1,1,3,3-tetrakis (3,5-dibromo-4-hydroxyphenyl) propane, , 1,3,3-tetrakis (3-phenyl-4-hydroxyphenyl) propane, 1,1,3,3-tetrakis (3,5-diphenyl-4-hydroxyphenyl) Propane, 1,1,3,3-tetrakis (3-methoxy-4-hydroxyphenyl) propane, 1,1,3,3-tetrakis (3,5-dimethoxy-4-hydroxyphenyl) propane, 1, 1,3,3-tetrakis (3-t-butyl-4-hydroxyphenyl) propane, 1,1,3,3-tetrakis (3,5-di-t-butyl-4-hydroxyphenyl) propane,

  1,1,4,4-tetrakis (4-hydroxyphenyl) butane, 1,1,4,4-tetrakis (3-methyl-4-hydroxyphenyl) butane, 1,1,4,4-tetrakis (3 5-dimethyl-4-hydroxyphenyl) butane, 1,1,4,4-tetrakis (3-chloro-4-hydroxyphenyl) butane, 1,1,4,4-tetrakis (3,5-dichloro-4-) Hydroxyphenyl) butane, 1,1,4,4-tetrakis (3-methoxy-4-hydroxyphenyl) butane, 1,1,4,4-tetrakis (3,5-dimethoxy-4-hydroxyphenyl) butane, , 1,4,4-tetrakis (3-bromo-4-hydroxyphenyl) butane, 1,1,4,4-tetrakis (3,5-dibromo-4-hydroxyphenyl) butane, 1,4,4-tetrakis (3-t-butyl-4-hydroxyphenyl) butane, 1,1,4,4-tetrakis (3,5-di -t- butyl-4-hydroxyphenyl) butane;

  α, α, α ′, α′-tetrakis (4-hydroxyphenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-hydroxyphenyl) -m-xylene, α, α, α ′ , Α′-tetrakis (4-hydroxyphenyl) -o-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-methylphenyl) -p-xylene, α, α, α ′, α '-Tetrakis (4-hydroxy-3-chlorophenyl) -p-xylene, α, α, α', α'-tetrakis (4-hydroxy-3-ethylphenyl) -p-xylene, α, α, α ', α′-tetrakis (4-hydroxy-3-isopropylphenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-chlorophenyl) -m-xylene, α, α, α ′ , Α′-tetrakis (4-hydroxy- -Chlorophenyl) -m-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-methylphenyl) -m-xylene, α, α, α ′, α′-tetrakis (4-hydroxy- 3-ethylphenyl) -m-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-methylphenyl) -o-xylene, α, α, α ′, α′-tetrakis (4- Hydroxy-3-chlorophenyl) -o-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-ethylphenyl) -o-xylene, α, α, α ′, α′-tetrakis (4 -Hydroxy-3-isopropylphenyl) -o-xylene,

  α, α, α ′, α′-tetrakis (4-hydroxy-3-t-butylphenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-bromophenyl)- p-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-iodophenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-methoxy) Phenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-ethoxyphenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3) -Isopropoxyphenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-t-butoxyphenyl) -p-xylene, α, α, α ′, α′-tetrakis ( 3-hydroxyphenyl) -p-xylene, α, α α ′, α′-tetrakis (3-hydroxy-4-chlorophenyl) -p-xylene, α, α, α ′, α′-tetrakis (3-hydroxy-4-bromophenyl) -p-xylene, α, α , Α ′, α′-tetrakis (3-hydroxy-4-iodophenyl) -p-xylene, α, α, α ′, α′-tetrakis (3-hydroxy-4-methoxyphenyl) -p-xylene, α, α, α ′, α′-tetrakis (3-hydroxy-4-ethoxyphenyl) -p-xylene, α, α, α ′, α′-tetrakis (2-hydroxyphenyl) -p-xylene, α, α, α ′, α′-tetrakis (2-hydroxy-4-chlorophenyl) -p-xylene, α, α, α ′, α′-tetrakis (2-hydroxy-4-methylphenyl) -p-xylene, α , Α, α ′, α′-tetrakis (2 Hydroxy-4-methoxyphenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3,5-dichlorophenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-Hydroxy-3,5-dimethylphenyl) -p-xylene, α, α, α ′, α′-tetrakis (4-hydroxy-3-chloro-5-methylphenyl) -p-xylene, α, α , Α ′, α′-tetrakis (4-hydroxyphenyl) -3-chloro-p-xylene, α, α, α ′, α′-tetrakis (4-hydroxyphenyl) -3-methyl-p-xylene, α , Α, α ′, α′-tetrakis (4-hydroxyphenyl) -3-methoxy-p-xylene, α, α-bis (4-hydroxyphenyl) -α ′, α-bis (3-chloro-4- Hydroxyphenyl) -p-xyle , Α, α′-bis (4-hydroxyphenyl) -α ′, α′-bis (3-methyl-4-hydroxyphenyl) -p-xylene, α, α-bis (4-hydroxyphenyl) -α ′ , Α′-bis (3-methoxy-4-hydroxyphenyl) -p-xylene, α, α, α′-tris (4-hydroxyphenyl) -α′-3-chlorophenyl-p-xylene, α, α, α′-tris (4-hydroxyphenyl) -α′-3-methylphenyl-p-xylene, α, α, α′-tris (4-hydroxyphenyl) -α′-3-methoxyphenyl-p-xylene; Etc.

(Ii) Curing agent and curing accelerator A compound (curing agent) that reacts with the epoxy group used in the present invention to cure the epoxy resin, and a compound that accelerates the curing rate of the compound that reacts with the epoxy group and cures the epoxy resin. The (curing accelerator) is not particularly limited, and any one of those conventionally used as curing agents and curing accelerators for conventional epoxy resins can be selected and used. For example, amine compounds, imidazole compounds, imidazoline compounds, amide compounds, ester compounds, phenol compounds, alcohol compounds, thiol compounds, ether compounds, thioether compounds, urea compounds, thiourea compounds Lewis acid compounds, phosphorus compounds, acid anhydride compounds, onium salt compounds, active silicon compounds-aluminum complexes, and the like.

Examples of the amine compound include aliphatic amines, alicyclic and heterocyclic amines, aromatic amines, and modified amines.
Aliphatic amines include ethylenediamine, trimethylenediamine, tetramethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenediamine, dimethylaminopropylamine, diethylaminopropylamine, trimethylhexamethylenediamine, Pentanediamine, bis (2-dimethylaminoethyl) ether, pentamethyldiethylenetriamine, alkyl-t-monoamine, 1,4-diazabicyclo (2,2,2) octane (triethylenediamine), N, N, N ′, N ′ -Tetramethylhexamethylenediamine, N, N, N ', N'-tetramethylpropylenediamine, N, N, N', N'-tetramethylethylenediamine, N, N-dimethylcyclohexane Triethanolamine, dimethylamino-ethoxy-ethoxy ethanol, dimethylamino hexanol and the like.

  Alicyclic and heterocyclic amines include piperidine, piperazine, menthanediamine, isophoronediamine, methylmorpholine, ethylmorpholine, N, N ′, N ″ -tris (dimethylaminopropyl) hexahydro-s-triazine, 3, 9-bis (3-aminopropyl) -2,4,8,10-tetraoxyspiro (5,5) undecane adduct, N-aminoethylpiperazine, trimethylaminoethylpiperazine, bis (4-aminocyclohexyl) methane, N , N′-dimethylpiperazine, 1,8-diazabicyclo (4,5,0) undecene-7, and the like.

Examples of aromatic amines include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, benzylmethylamine, dimethylbenzylamine, m-xylenediamine, pyridine, and picoline.
Modified amines include epoxy compound addition polyamine, Michael addition polyamine, Mannich addition polyamine, thiourea addition polyamine, ketone-capped polyamine, dicyandiamide, guanidine, organic acid hydrazide, diaminomaleonitrile, amine imide, boron trifluoride-piperidine complex, Examples thereof include boron trifluoride-monoethylamine complex.

  Examples of imidazole compounds include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-isopropylimidazole, 2-n-propylimidazole, 2-undecyl-1H-imidazole, 2-heptadecyl-1H-imidazole, 1,2- Dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-1H-imidazole, 4-methyl-2-phenyl-1H-imidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-ethyl-4 Methyl imidazolium trimellitate, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2′-methylimidazolyl- ( 1 ′)]-ethyl-s-triazine, 2,4-diamino-6- (2′-undecylimidazolyl-)-ethyl-s-triazine, 2,4-diamino-6- [2′-ethyl-4 -Imidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole Isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-cyanoethyl-2-phenyl-4,5-di (2-cyanoethoxy) methylimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium Examples include chloride, 1-benzyl-2-phenylimidazole hydrochloride, 1-benzyl-2-phenylimidazolium trimellitate, and the like.

Examples of the imidazoline compound include 2-methylimidazoline and 2-phenylimidazoline.
Examples of the amide compound include polyamide obtained by condensation of dimer acid and polyamine.
Examples of ester compounds include active carbonyl compounds such as aryl and thioaryl esters of carboxylic acids.

Phenol compounds, alcohol compounds, thiol compounds, ether compounds, and thioether compounds include phenol novolak, cresol novolak, polyol, polymercaptan, polysulfide, 2- (dimethylaminomethylphenol), 2, 4, 6 -Tris (dimethylaminomethyl) phenol, tri-2-ethylhexyl hydrochloride of 2,4,6-tris (dimethylaminomethyl) phenol, and the like.
Examples of urea compounds, thiourea compounds, and Lewis acid compounds include butylated urea, butylated melamine, butylated thiourea, and boron trifluoride.

  Examples of the phosphorus compound include organic phosphine compounds, for example, alkylphosphine such as ethylphosphine and butylphosphine, first phosphine such as phenylphosphine, dialkylphosphine such as dimethylphosphine and dipropylphosphine, 2 phosphine; a third phosphine such as trimethylphosphine and triethylphosphine;

  Examples of the acid anhydride compounds include phthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, maleic anhydride, Tetramethylene maleic anhydride, trimellitic anhydride, chlorendic anhydride, pyromellitic anhydride, dodecenyl succinic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bis (anhydrotrimellitate), methylcyclohexene tetracarboxylic anhydride, And polyazeline acid anhydride.

  Moreover, as onium salt compounds and active silicon compounds-aluminum complexes, aryldiazonium salts, diaryliodonium salts, triarylsulfonium salts, triphenylsilanol-aluminum complexes, triphenylmethoxysilane-aluminum complexes, silyl peroxide-aluminum complexes And triphenylsilanol-tris (salicylide) aluminum complex.

  The inclusion compound of a curing agent, a curing accelerator, and a tetrakisphenol compound is, for example, a tetrakisphenol compound when the curing agent, an amine compound that is a curing accelerator, or an imidazole compound is a liquid. When the compound of the curing agent and the curing accelerator is a solid by adding it directly to the liquid and reacting it, putting the tetrakisphenol-based compound in a liquid containing these compounds and reacting, or a compound that is a solid Can be synthesized with a high selectivity and a high yield.

  The clathrate compound of the present invention is formed by guest molecules entering into crystal lattice vacancies formed by host molecules. Therefore, which compound is easily taken up as a guest is governed by the size, solidity, polarity, solubility, etc. of the guest molecule. The clathrate compound produced is a crystalline solid.

After completion of the reaction, the desired clathrate compound can be isolated by ordinary separation means.
The structure of the clathrate compound obtained can be confirmed by known analytical means such as NMR, IR spectrum, and mass spectrum.

The 50% volume average particle size of the clathrate compound used in the present invention is not particularly limited, but is usually about 0.01 to 80 μm, preferably about 0.01 to 10 μm, more preferably about 0.1 to 4 μm. is there. It is not preferable to produce an inclusion compound having a volume average particle diameter of less than about 0.01 μm because the productivity of the compound itself deteriorates. On the other hand, those having a volume average particle diameter exceeding about 80 μm are not preferable because the low-temperature curability and the appearance of the coating film are deteriorated.
The 50% volume average particle diameter represents the particle diameter μm at which the cumulative curve is 50% when the cumulative curve is obtained with the volume of the powder group as 100%.

2) Production of powder coating composition The first powder coating composition of the present invention comprises an epoxy resin, a polyester resin, and an inclusion compound (a), optionally a curing agent or a curing accelerator, and other additives. For example, using a kneader or an extruder, the mixture of a predetermined amount of the agent is melted and kneaded at a temperature and time conditions that do not cause thickening and gelation, cooled, pulverized, and applied to a classifier. Can be manufactured. The second powder coating composition of the present invention comprises a mixture comprising a predetermined amount of an epoxy resin, a polyester resin, and an inclusion compound (b), and a curing agent or a curing accelerator, and other additives as required. For example, it can be produced by using a kneader, an extruder or the like, melting and kneading at a temperature and time conditions that do not cause thickening and gelation, cooling, pulverizing, and applying to a classifier.

  The amount of the clathrate compound to be used may be the same amount as that of a usual curing agent or curing accelerator such as an amine-based or imidazole-based clathrate, and depends on the curing method. In the case of an addition type curing agent in which a curing agent molecule is always incorporated into a cured resin by reacting with an epoxy group, depending on the properties of the required resin, it is usually included in 1 mol of an epoxy group. The clathrate compound is used so that the curing agent is about 0.3 to 1.0 mol. In addition, in the case of a polymerization type curing agent or a photoinitiated type curing agent that induces a polymerization addition reaction between oligomers without causing the curing agent molecule to be incorporated into the resin, it is also a curing accelerator. In the case of using as, for example, 0.2 mol or less of the clathrate compound is sufficient for 1 mol of the epoxy group. In particular, in the present invention, by using an inclusion compound using a tetrakisphenol compound, even a trace amount is sufficient, and a usage amount of 0.001 to 0.1 mol, further 0.001 to 0.05 mol may be sufficient. These inclusion compounds can be used alone or in combination of two or more.

In the first powder coating composition of the present invention, it is preferable to further add a curing accelerator, and in the second powder coating composition, it is preferable to further add a curing agent.
As the curing agent and the curing accelerator used here, the same ones listed as the curing agent and the curing accelerator can be used.

  If desired, other additives can be added to the powder coating composition of the present invention. Examples of other additives include plasticizers, reactive diluents, extenders, fillers, reinforcing agents, colorants, flame retardants, thickeners, and release agents. The blending amount of these additives is not particularly limited, and the blending amount can be appropriately determined within the limit that the effects of the present invention can be obtained.

  Further, the first and / or second powder coating composition of the present invention may contain other resins in addition to the epoxy resin and the polyester resin. Examples of other resins include acrylic resins, silicon resins, polyurethane resins, and the like.

The powder coating composition of the present invention can be applied by a known coating method.
Examples thereof include an electrostatic powder coating method, an uncharged powder coating method, a frictionally charged powder coating method, and a fluidized immersion method. In any coating method, when the powder coating composition of the present invention is used, a good cured coating film can be formed at a low heating temperature.

  Even when the powder coating composition of the present invention is stored for a long period of time, the curing reaction hardly proceeds, and the storage stability is excellent.

  The powder coating composition of the present invention, after being applied to a substrate, is quickly released from the host component by heating the guest component of the curing agent and / or curing accelerator, and the released curing agent, epoxy resin and The cured curing agent forms a cured coating film by acting as a catalyst that promotes the curing reaction between the curing agent and the epoxy resin and / or the polyester resin. be able to.

Although the thickness of the coating film obtained is not specifically limited, Usually, it is about 40-200 micrometers, Preferably it is the range of about 50-100 micrometers.
By heating the coating film, the curing agent and / or curing accelerator included in the inclusion compound is released, and a cured film can be formed by the progress of the curing reaction.

Further, according to the powder coating composition of the present invention, the temperature for forming the cured film needs to be set higher than in the case where the imidazole group-containing curing agent is not included, but the conventional high temperature curing type The cured film can be formed at a lower temperature than the curing agent. Therefore, even if it is a base material with poor heat resistance, the powder coating composition of this invention can be applied and a favorable cured coating film can be formed.
The heating temperature for obtaining the cured film is not particularly limited, and the optimum conditions may be appropriately determined and selected according to the type of guest of the curing agent or curing accelerator and the blending ratio with the host. The heating temperature (curing temperature) is usually 20 to 300 ° C, preferably 50 to 200 ° C.

  The powder coating composition of the present invention can be suitably used as a coating material in the field of surface coating of substrates such as paper, plastic, metal, and combinations thereof, and home appliances, building materials, automobile parts, and the like.

  EXAMPLES Next, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to the following Examples at all.

Production Example 1 Production of Inclusion Compound A 2-Methylimidazole (18 g, 0.22 mol) and 200 ml of ethyl acetate were placed in a container equipped with a reflux tube, and TEP (39.8 g, 0.1 mol) was added thereto, followed by reflux temperature. And stirred for 1 minute to 24 hours. After completion of the reaction, the reaction solution was returned to room temperature, and the precipitated crystals were collected by filtration and dried under reduced pressure at room temperature to 120 ° C. Yield 90%
The inclusion compound A was TEP as a host compound and 2-methylimidazole (2MeIm) as a guest compound, and the molar ratio was TEP: 2-MeIm = 1: 2.

Production Example 2 Production of Inclusion Compound B To a container equipped with a reflux tube, TEP (39.8 g, 0.1 mol) and 200 ml of methanol were added and heated to reflux temperature. There, the methanol 50ml solution of 2-ethyl-4-methylimidazole (24.2g, 0.22mol) was dripped. After the slurry in the reaction vessel was once dissolved, crystals were deposited. After cooling the reaction solution to room temperature, the precipitated crystals were collected by filtration and dried under reduced pressure at room temperature to 120 ° C. to obtain inclusion compound B. Yield 80%
The inclusion compound B has TEP as a host compound and 2-ethyl-4-methylimidazole (2Et-4-MeIm) as a guest compound, and the molar ratio is TEP: 2Et-4-MeIm = 1: 2.

Example 1 Production of powder coating composition 1 Epoxy resin (trade name: Epicron 2050, manufactured by Dainippon Ink & Chemicals, Inc.) 55 parts by weight, polyester resin (trade name: Finedick M8830, Dainippon Ink & Chemicals, Inc.) 4.0 parts by weight of inclusion compound A in terms of 2-methylimidazole was added to 45 parts by weight. The powder coating composition 1 was obtained by kneading at 25 ° C. for 10 minutes.

Comparative Example 1 Production of Powder Coating Composition 2 In Example 1, powder coating composition 2 was prepared in the same manner as in Example 1 except that 4 parts by weight of 2-methylimidazole was used instead of inclusion compound A. Got.

Example 2 Production of Powder Coating Composition 3 In Example 1 except that 4 parts by weight of inclusion compound B in terms of 2-ethyl-4-methylimidazole was used instead of inclusion compound A. Example 1 In the same manner as above, a powder coating composition 3 was obtained.

Comparative Example 2 Production of Powder Coating Composition 4 In Example 2, powder coating composition was used in the same manner as in Example 2 except that 4 parts by weight of 2-ethyl-4-methylimidazole was used instead of inclusion compound B. Product 4 was obtained.

(DSC measurement of powder coating compositions 1-4)
A part of each of the obtained powder coating compositions 1 to 4 was collected, and using a differential scanning calorimeter (DSC, manufacturer name, model), a heating rate of 10 ° C. under a nitrogen stream of 30 ml / min. The heat generation based on the curing reaction of the resin composition 1 was measured under the conditions of / min.

A DSC chart of the powder coating composition 1 is shown in FIG. In FIG. 1, the horizontal axis represents the measured temperature (° C.), and the vertical axis represents the calorific value (Heat Flow / mW) (hereinafter the same in FIGS. 2 to 4).
From FIG. 1, the curing start temperature of the powder coating composition 1 was 99.3 ° C., and the peak of the heat of reaction was 148.3 ° C.
The DSC measurement of the powder coating composition 2 was performed in the same manner as in Example 1. A DSC chart of the powder coating composition 2 is shown in FIG.
From FIG. 2, the curing start temperature of the powder coating composition 2 was 73.3 ° C., and the peak of the heat of reaction was 114.9 ° C.
The DSC measurement of the powder coating composition 3 was performed in the same manner as in Example 1. A DSC chart of the powder coating composition 3 is shown in FIG.

From FIG. 3, the curing start temperature of the powder coating composition 3 was 113.2 ° C., and the peak of the heat of reaction was 156.8 ° C.
The powder coating composition 4 was subjected to DSC measurement in the same manner as in Example 1. A DSC chart of the powder coating composition 4 is shown in FIG.
Moreover, from FIG. 4, the hardening start temperature of the powder coating composition 4 was 72.3 degreeC, and the peak of reaction heat was 138.1 degreeC.

  From FIG. 1 and FIG. 2, in the powder coating composition of Example 1 containing the compound including 2-methylimidazole, continuous heat generation is observed from 100 ° C. to 170 ° C. On the other hand, in the powder coating composition of Comparative Example 1 containing no clathrate compound, continuous heat generation was observed from 80 ° C to 170 ° C. That is, the powder coating composition of Example 1 has a higher curing reaction start temperature than the powder coating composition of Comparative Example 1, but the upper limit of the curing temperature is almost the same. Recognize.

  From FIG. 3 and FIG. 4, in the powder coating composition of Example 2 containing the compound which included 2-ethyl-4-methylimidazole, continuous heat_generation | fever was recognized from 110 to 180 degreeC. On the other hand, in the powder coating composition of Comparative Example 2 containing no clathrate compound, continuous heat generation was observed from 80 ° C to 180 ° C. That is, the powder coating composition of Example 2 has a higher curing reaction start temperature and upper limit of the curing temperature than the powder coating composition of Comparative Example 2, but the curing temperature range is narrow. You can see that

(Storage stability test of powder coating composition)
The powder coating compositions 1 to 4 obtained above were stored at 40 ° C. for 7 days for 1 month, and the coating film was heated at 120 ° C. for 20 minutes with an electrostatic powder coating machine (film thickness 80 μm). (Baked). As compared with the coating film before storage by visually observing the smoothness and gloss of the obtained coating film surface, the smoothness and gloss are the same as the initial one, the smoothness and the gloss are slightly inferior, The case where the smoothness and gloss were remarkably inferior was evaluated as x. Moreover, the thing which thickened and gelatinized during manufacture of a powder coating material was set to xx. The results are shown in Table 1.

  From Table 1, the powder coating compositions of Examples 1 and 2 can form a cured coating film excellent in smoothness and gloss even when stored at 40 ° C. for 7 days and 1 month. It was. In contrast, the powder coating compositions of Comparative Examples 1 and 2 obtained a cured coating film with poor smoothness and gloss after being stored at 40 ° C. for 7 days and 1 month. It was found that the storage stability was inferior to that of the powder coating composition of No. 2.

1 is a diagram showing a DSC chart of a powder coating composition 1. FIG. It is a figure which shows the DSC chart of the powder coating composition 2. FIG. It is a figure which shows the DSC chart of the powder coating composition 3. FIG. It is a figure which shows the DSC chart of the powder coating composition 4.

Claims (10)

  An epoxy-polyester powder coating composition comprising an inclusion compound (a) having an epoxy resin, a polyester resin and a multi-molecular host compound as a host compound and a curing agent as a guest compound.   2. The powder coating composition according to claim 1, wherein the multimolecular host compound is a compound having two or more hydroxyl groups and two or more aromatic groups in the molecule. The multimolecular host compound has the formula (I)

Wherein, X _{is, (CH 2)} n _(n is. Represents an integer of 0 to 3), or an even phenylene group optionally having a ^substituent, R 1 to R ⁸ are each independently And a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an optionally substituted phenyl group, a halogen atom, or an alkoxy group having 1 to 6 carbon atoms. The powder coating composition according to claim 1 or 2, which is a tetrakisphenol compound represented by the formula:   The powder coating composition according to any one of claims 1 to 3, further comprising a curing accelerator.   The powder coating composition according to any one of claims 1 to 4, wherein the clathrate compound (a) is contained in an amount of 0.001 to 0.1 mol per mol of the epoxy ring of the epoxy resin. .   An epoxy-polyester powder coating composition comprising an inclusion compound (b) having an epoxy resin, a polyester resin and a multi-molecular host compound as a host compound and a curing accelerator as a guest compound.   The powder coating composition according to claim 6, wherein the multimolecular host compound is a compound having two or more hydroxyl groups and two or more aromatic groups in the molecule. The multimolecular host compound has the formula (I)

Wherein, X _{is, (CH 2)} n _(n is. Represents an integer of 0 to 3), or an even phenylene group optionally having a ^substituent, R 1 to R ⁸ are each independently And a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a phenyl group optionally having a substituent, a halogen atom, or an alkoxy group having 1 to 6 carbon atoms. The powder coating composition according to claim 6 or 7, which is a tetrakisphenol compound represented by the formula:   The powder coating composition according to any one of claims 6 to 8, further comprising a curing agent.   The powder coating composition according to any one of claims 6 to 9, wherein the clathrate compound (b) is contained in an amount of 0.001 to 0.1 mol per mol of the epoxy ring of the epoxy resin. .

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