JP2005029515A - Semicarbazide curing agent and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semicarbazide curing agent capable of obtaining coating film of high alkali yellowing resistance. <P>SOLUTION: The semicarbazide curing agent is characterized by that 1.0 g of an aqueous solution of the curing agent with semicarbazide groups adjusted to a level of 0.1 mmol/g, 5.0 g of ethylene glycol monobutyl ether and 1.0 g of a 1N sodium hydroxide aqueous solution are mixed together, the mixture is then left to stand at 20°C for 24 h, and the resulting mixed solution gives an absorbance of ≤1.0 abs. at 425 nm wavelength in a 1cm×1cm quartz cell. A method for producing the curing agent is provided. A water-based resin composition comprising the curing agent and a water-based resin is provided. A base coated with the water-based resin composition is also provided. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  Semicarbazide curing agents are useful in raw materials for water-based paints or use of the curing agents.

  In recent years, water-based emulsions have been attracting attention as a conversion material from organic solvent to water in the coating field, but still have sufficient physical properties in terms of water resistance, stain resistance, hardness, etc. compared to organic solvent-based coating materials. Not.

  For the purpose of improving these physical properties, it is common practice to introduce a functional group into an aqueous emulsion to form a coating film made of a crosslinked polymer (hereinafter often referred to as “crosslinked coating film”). . The aqueous emulsion forming the crosslinked coating film is a mixture of a curing agent and a polymer from the viewpoint of workability, workability, and the like. There is a great demand for a one-pack cold-curing, one-pack type that can form a cured film, and recently, in response to this requirement, hydrazone cross-linking aqueous solution using dehydration condensation reaction of carbonyl group and hydrazide group. Emulsions are attracting attention.

  For example, [Patent Document 1] Japanese Examined Patent Publication No. 46-20053, [Patent Document 2] JP-A 57-3850, [Patent Document 3] JP 57-3857, [Patent Document 4] JP In Japanese Patent Application Laid-Open No. 58-96643 and [Patent Document 5] Japanese Patent Application Laid-Open No. 4-249487, a room temperature curing property (cold) is obtained by adding dicarboxylic acid dihydrazide as a curing agent to a carbonyl group-containing copolymer aqueous dispersion. -curingability) and storage stability, and it has been proposed to provide a coating composition excellent in hardness, stain resistance and the like. However, in this method, the dicarboxylic acid dihydrazide used as a curing agent is hydrolyzed during storage of the coating composition to reduce the crosslinking ability (that is, the curing characteristics), and has excellent hardness, stain resistance, Not only does the ability to form a cross-linked coating film having solvent resistance and the like decrease with time, but the above publication discloses that the dicarboxylic acid dihydrazide has low compatibility with a carbonyl group-containing copolymer such as adipic acid dihydrazide and Since a highly hydrophilic compound is used, the resulting cross-linked film has a drawback that the water resistance is remarkably inferior.

  As described above, the conventional aqueous resin composition containing the conventional curing agent and the polycarbonyl compound deteriorates with time, so that sufficient curing performance is obtained when this composition is applied to the substrate surface. I couldn't show it. Furthermore, since dicarboxylic acid dihydrazide which is inferior in compatibility with the polycarbonyl compound is used as a curing agent, there is a problem that the water resistance of the crosslinked film obtained by coating becomes very poor. [Patent Document 6] WO 96/01252 pamphlet describes a polyisocyanate having 3 to 20 isocyanate groups (hereinafter often referred to as “NCO groups”), hydrazine or a derivative thereof, or a terminal non-blocked body thereof. At least one selected from the group consisting of a semicarbazide derivative obtained by reacting a mixture of a terminal blocker and a terminal blocker, and at least one selected from the group consisting of the semicarbazide derivative and a terminal blocker, and A semicarbazide composition containing at least one selected from a hydrophilic group-containing compound and a terminal blocker thereof has been proposed as a curing agent. However, a coating film obtained by applying and curing the aqueous resin composition containing the curing agent on the substrate surface has a drawback that it is yellowed by an alkaline solution.

Japanese Patent Publication No.46-20053 Japanese Patent Laid-Open No. 57-3850 Japanese Patent Laid-Open No. 57-3857 JP 58-96643 A Japanese Patent Laid-Open No. 4-249487 International Publication No. 96/01252 Pamphlet

  That is, an object of the present invention is to provide a semicarbazide curing agent-containing aqueous resin composition capable of obtaining a coating film excellent in alkali yellowing resistance.

  As a result of intensive studies to achieve the above object, the present inventors have found that 1.0 g of a semicarbazide curing agent aqueous solution adjusted to have a semicarbazide group of 0.1 mmol / g, and 5.0 g of ethylene glycol monobutyl ether. And 1.0 g of 1N sodium hydroxide aqueous solution were mixed and allowed to stand at 20 ° C. for 24 hours. When this mixed solution was put into a 1 cm square quartz cell, the absorbance at 425 nm was 1.0 abs. It has been found that a coating film excellent in alkali yellowing resistance can be obtained by using a semicarbazide curing agent characterized by the following.

That is, the present invention is the following (1) to (7).
(1) After mixing 1.0 g of a semicarbazide curing agent aqueous solution with the semicarbazide group adjusted to 0.1 mmol / g, 5.0 g of ethylene glycol monobutyl ether and 1.0 g of 1N sodium hydroxide aqueous solution, and after standing at 20 ° C. for 24 hours The absorbance at 425 nm when this mixed solution was put in a 1 cm square quartz cell was 1.0 abs. A semicarbazide curing agent characterized by:
(2) The method for producing a semicarbazide curing agent according to claim 1, wherein the whole process for producing the semicarbazide curing agent is carried out at a temperature of 50 ° C. or lower.
(3) The method for producing a semicarbazide curing agent according to claim 2, wherein the step of producing the semicarbazide curing agent removes the solvent by crystallization.
(4) The method for producing a semicarbazide curing agent according to claim 2 or 3, wherein the semicarbazide curing agent is synthesized by reacting isophorone diisocyanate and a hydrazine derivative.
(5) A semicarbazide curing agent, characterized in that the production method is any one of claims 2 to 4.
(6) An aqueous resin composition comprising the semicarbazide curing agent according to claim 1 or 5 and an aqueous resin.
(7) A composite in which the aqueous resin composition according to claim 6 is applied to a substrate.

  A semicarbazide curing agent-containing aqueous resin composition excellent in alkali yellowing resistance is provided.

  The present invention will be described in detail below.

  Confirmation of a semicarbazide curing agent that is excellent in alkali yellowing resistance and capable of obtaining a coating film is as follows: 1.0 g of an aqueous semicarbazide curing agent solution adjusted to have a semicarbazide group of 0.1 mmol / g, ethylene glycol mono After mixing 5.0 g of butyl ether and 1.0 g of a 1N aqueous sodium hydroxide solution and placing it at 20 ° C. for 24 hours, the absorbance at 425 nm when this mixed solution was put in a 1 cm square quartz cell was 1.0 abs. This can be confirmed by: The semicarbazide group of the obtained semicarbazide curing agent can be measured by, for example, redox titration using potassium iodate.

  Such a semicarbazide curing agent can be synthesized, for example, by reacting an organic compound (A) having two or more NCO groups in the molecule with hydrazine or a hydrazine derivative (B). In this synthesis method, the total process means the process of reacting compound (A) and compound (B), the process of extracting the semicarbazide curing agent from the reaction solution, the process of removing the solvent, and drying the extracted semicarbazide to a predetermined concentration. The process of diluting with an appropriate solvent.

Here, examples of the organic compound (A) having two or more NCO groups in the molecule include diisocyanate compounds having two NCO groups and polyisocyanates having three or more NCO groups. For example, alkylene diisocyanate such as hexamethylene diisocyanate (HDI); cycloalkylene such as 4,4′-methylenebiscyclohexyl diisocyanate (hydrogenated MDI), isophorone diisocyanate (IPDI), dimethylcyclohexane diisocyanate (hydrogenated XDI) Diisocyanates; 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate and mixtures thereof (TDIs), diphenylmethane-4,4′-diisocyanate (MDI),
Arylene diisocyanates such as naphthalene-1,5-diisocyanate (NDI), 3,3-dimethyl-4,4-diphenylene diisocyanate (TODI), crude TDIs, polymethylene polyphenyl diisocyanate, crude MDI, phenylene diisocyanate, and xylylene diisocyanate (XDI) and other aralkylene diisocyanates, and combinations thereof. Examples of polyisocyanates having three or more NCO groups include diisocyanates, biuret bonds, urea bonds, isocyanurate bonds, urethane bonds, allophanates. Examples thereof include those obtained by re-oligomerization by forming a bond, a uretdione bond and the like to form a trimer to a 20-mer.

  With respect to the production method of these polyisocyanates and the bonds in the polyisocyanates, for example, G. Oertel, Polyurethane Handbook (German Hanser Publishers, 1985) can be referred to. Of these, isophorone diisocyanate is preferred because the resulting semicarbazide curing agent has high water solubility.

  Examples of the hydrazine or hydrazine derivative (B) used in the present invention include hydrazine and hydrates thereof; monoalkyl-substituted hydrazine compounds such as monomethyl hydrazine, monoethyl hydrazine and monobutyl hydrazine; ethylene-1,2-dihydrazine, propylene- Dihydrazine compounds such as 1,3-dihydrazine and butylene-1,4-dihydrazine; oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, maleic acid dihydrazide, fumarate Dicarboxylic acid dihydrazides such as acid dihydrazide, itaconic acid dihydrazide, isophthalic acid dihydrazide, phthalic acid dihydrazide; tricarboxylic acid trihydrazides such as trimellitic acid trihydrazide and mixtures thereof Thing, and the like.

  Further, the functional group ratio of the compounds (A) and (B) to be reacted is preferably 1 or more for the compound (B) / {NCO group in the compound (A)}. A larger value is more preferable, and 1.5 to 5.0 is more preferable. The semicarbazide curing agent is preferably 5.0 or less because the semicarbazide curing agent can be easily extracted from the solution after completion of the reaction. These reactions can be synthesized using an appropriate solvent as necessary.

  Examples of the solvent that can be used include alcohols such as methanol, ethanol, isopropanol, 1-butanol, 2-butanol butyl cellosolve, propylene glycol monopropyl ether, esters such as methyl acetate, ethyl acetate, and butyl acetate, and diethyl ether. , Ethers such as tetrahydrofuran, dioxane, dimethoxyethane, and diethylene glycol dimethyl ether, ketones such as acetone, methylethylkenton, and methylisobutylketone, and amides such as dimethylformamide and dimethylacetamide. Among these, ketones cause dehydration condensation with a semicarbazide curing agent, and therefore it is necessary to hydrolyze with water after the reaction.

  In addition, alcohols are preferable because both the compound (A) and the compound (B) are dissolved, and methanol, ethanol, butyl cellosolve, and propylene glycol monopropyl ether are more preferable. These solvents can be used alone or in combination of two or more. These reactions can be carried out at an arbitrary temperature. However, since a curing agent synthesized at a high temperature often turns yellow in the presence of an alkali, it is preferably carried out at 10 to 100 ° C., more preferably 10 to 50 ° C. More preferably, it is carried out at ° C.

  Further, the compounds (A) and (B) can be mixed by any method, but from the viewpoint of suppressing side reactions, a method of gradually adding the compound (A) to the compound (B) and synthesizing it, Or the method of adding a compound (A) and a compound (B) simultaneously in a solvent, or the method of adding a compound (A) and a compound (B) to a compound (B) simultaneously is preferable. In addition, these compounds (A) and (B) may be added as they are, or may be added as a solution.

  Extraction methods include, for example, distillation, crystallization, column chromatography, etc., but the semicarbazide curing agent obtained when heating during extraction often yellows in the presence of alkali, so extraction that does not require a heating step Methods such as crystallization and column chromatography are preferred, and crystallization is more preferred because a large amount of treatment can be performed at once.

  The solvent used for crystallization is not particularly limited as long as it does not react with the semicarbazide curing agent. For example, alcohols such as methanol, ethanol, isopropanol, 1-butanol, 2-butanol butyl cellosolve, propylene glycol monopropyl ether, etc. , Esters such as methyl acetate, ethyl acetate and butyl acetate, ethers such as diethyl ether, tetrahydrofuran, dioxane, dimethoxyethane and diethylene glycol dimethyl ether, and amides such as dimethylformamide and dimethylacetamide. Among these, ethers whose solubility of the semicarbazide curing agent varies greatly depending on the temperature are preferable, and dioxane, tetrahydrofuran, and dimethoxyethane are more preferable.

  The semicarbazide curing agent of the present invention can be used after being diluted with a solvent after extraction. Suitable solvents for dilution include water, alcohols such as methanol, ethanol, isopropanol, and butanol, and film-forming aids such as butyl cellosolve, texanol, and butyl carbitol. To reduce the volatile organic solvent Water is preferred. In addition, the purpose or mechanism for improving stability upon dilution is not clear, but various additives can be added for the purpose of preventing the semicarbazide curing agent from yellowing in the presence of alkali.

  Additives that can be added include, for example, film-forming aids, surfactants, antioxidants, etc. Examples of film-forming aids include butyl cellosolve, texanol, butyl carbitol, butyl carbitol acetate, diethyl Diglycol, ethylene glycol mono-2-ethylhexyl ether, dibutyl phthalate, dioctyl phthalate, propylene glycol-n-butyl ether, dipropylene glycol-n-butyl ether, tripropylene glycol-n-butyl ether, dipropylene glycol methyl ether, tri Examples include propylene glycol methyl ether.

  Examples of surfactants include anionic surfactants such as fatty acid soaps, alkyl sulfonates, alkyl sulfosuccinates, alkyl succinates, polyoxyethylene alkyl sulfates, polyoxyethylene alkyl aryl sulfates, and polyoxyethylenes. Non-reactive nonionic surfactants such as alkyl aryl ethers, polyoxyethylene sorbitan fatty acid esters, oxyethylene oxypropylene block copolymers, α- [1-[(allyloxy) methyl] -2- (nonylphenoxy) ethyl] -ω -Reactive nonionic surfactants such as hydroxypolyoxyethylene (for example, trade names: Adeka Soap NE-20, NE-30, NE-40 and the like) and the like.

  As the antioxidant, for example, ascorbic acid, dialkyldithiocarbamate, or a compound having a dialkyl semicarbazide group (for example, HN-130, HN-200, HN-300F, HN-300P (all of which are manufactured by Nippon Hydrazine Co., Ltd.) )), ADK STAB PEP-4C, ADK STAB PEP-8, ADK STAB 11C, ADK STAB PEP-36, ADK STAB HP-11, ADK STAB 260, ADK STAB 522A, ADK STAB 329K, ADK STAB 1500, ADK STAB C, ADK STAB 135A, ADK STAB 30A, 23, ADK STAB AO-30 (all Asahi Denka Kogyo Co., Ltd.),

  Irganox PS800FL, Irganox PS802FL, Irganox 245, Irganox 259, Irganox 565, Irganox 1010, Irganox 1035, Irganox 1076, Irganox 1098, Irganox 1222, Irganox 1330, Irganox 1425, Irganox 3114, Irganox 1520, Irganox 1135, Irganox 1141, Irgafos 38, Irgafos P-EPQ, Irgafos 126 (all manufactured by Ciba Specialty Chemicals Co., Ltd.), Sumilizer TPM, Summarizer TP-D, Summarizer TL, Summarizer MB, Sumilizer BHT, Summarizer MDP-S, Sumilizer GA-80, Summarizer BBM-S, Sumilizer WX-R, Sumilizer GM, Sumilizer GS, Sumilizer TNP, Sumilizer TPP-P, (manufactured by Sumitomo Chemical Co., both more than Co., Ltd.) Sumilizer P-16,

  2,6-di-t-butyl-4-methylphenol, 2-t-4,6-dimethylphenol, 2,6-di-t-butyl-4-ethylphenol, 2,6-di-t-butyl -4-n-butylphenol, 2,6-di-t-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4-methylphenol, 2- (α-methylcyclohexyl) -4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6-tricyclohexylphenol, 2,6-dinonyl-4-methylphenol, 2,6-di-t-butyl-4-methoxymethylphenol, 2 , 4-Dimethyl-6- (1'-methyl-undec-1'-yl) -phenol, 2,4-dimethyl-6- (1'-methyl-heptadeca-1'-yl) -phenol, 2 4-dimethylamino-6- (1'-methyl - 1'-yl) - phenol and mixtures thereof,

  2,4-di-octylthiomethyl-6-tert-butylphenol, 2,4-dioctylthiomethyl-6-methylphenol, 2,4-dioctylthiomethyl-6-ethylphenol, 2,6-di- Dodecylthiomethyl-4-nonylphenol and mixtures thereof; 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone, 2 , 6-Diphenyl-4-octadecyloxyphenol, 2,6-di-t-butylhydroquinone, 2,5-di-t-butyl-4-hydroxyanisole, 3,5-di-t-butyl-4-hydroxy Anisole, 3,5-di-t-butyl-4-hydroxyphenyl stearate, bis (3,5-di-t-butyl-4-hydroxyphenyl) Di Bae - DOO and mixtures thereof,

2,4-bis-octylmercapto-6- (3,5-di-tert-butyl-4-hydroxyanilino) -1,3,5-triazine, 2-octylmercapto-4,6-bis (3 5-Di-tert-butyl-4-hydroxyanilino) -1,3,5-triazine, 2-octylmercapto-4,6-bis (3,5-di-tert-butyl-4-hydroxyphenoxy)- 1,2,3-triazine, 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -isocyanurate, 1,3,5-tris (4-tert-butyl-3) -Hydroxy-2,6-dimethylbenzyl) -isocyanurate, 2,4,6-tris (3,5-di-t-butyl-4-hydroxyphenylethyl) -1,3,5-triazine,
5-tris (3,5-di-t-butyl-4-hydroxyphenylpropionyl) -hexahydro-1,3,5-triazine, 1,3,5-tris (3,5-dicyclohexyl-4-hydroxybenzyl) -Isocyanurate 2,2'-methylenebis (6-t-butyl-4-methylphenol), 2,2'-methylenebis (6-t-butyl-4-ethylphenol), 2,2'-ethylidenebis (4 , 6-di-t-butylphenol), 2,2′-ethylidenebis (6-t-butyl-4-isobutylphenol), 4,4′-methylenebis (2,6-di-t-butylphenol),

  4,4′-methylenebis (6-tert-butyl-2-methylphenol), 1,1-bis (5-tert-butyl-4-hydroxy-2-methylphenyl) butane, ethylene glycol bis [3,3 ′ -Bis (3'-t-butyl-4'-hydroxyphenyl) butyrate] and the like; 1,3,5-tris (3,5-di-t-butyl-4-hydroxybenzyl) -2,4,6- Trimethylbenzene, 1,4-bis (3,5-di-t-butyl-4-hydroxybenzyl) -2,3,5,6-tetramethylbenzene, 2,4,6-tris (3,5-di -T-4-hydroxybenzyl) -phenol and the like.

  Although there is no restriction | limiting in the addition amount of these additives, it is preferable that it is 1/10 or less with respect to the mass of a semicarbazide hardening | curing agent, and it is 1/20 or less for the performance improvement as a coating material when mix | blending with water-system resin. More preferably.

  The aqueous resin composition of the present invention contains a semicarbazide curing agent and an aqueous resin. Furthermore, it is preferable to contain a polycarbonyl compound and / or a polyepoxy compound as an aqueous resin. Among the aqueous resin compositions, the combination of a semicarbazide curing agent and a polycarbonyl compound has excellent storage stability and a film excellent in weather resistance, water resistance, stain resistance, hardness, etc. at a relatively low temperature. It is particularly preferable because it can be given.

  Examples of the polycarbonyl compound include a carbonyl group-containing copolymer, and a carbonyl group-containing mono- or polyalcohol having a carbonyl group such as hydroxyacetone as described in JP-A-2-238015. Examples thereof include polyurethanes, acetoacetylated polyvinyl alcohol, polyvinyl alcohol resins having a diacetone group in the side chain, acetoacetylated hydroxyalkylcellulose, and the like, as described in JP-A-9-324095, and combinations thereof. .

  Among these, a preferred polycarbonyl compound is a copolymer of a carbonyl group-containing ethylenically unsaturated monomer (α) and an ethylenically unsaturated monomer (β) copolymerizable with the monomer (α). A copolymer containing a carbonyl group obtained by polymerization, more preferably a polycarbonyl compound containing 0.1 to 30% by mass of a carbonyl group-containing ethylenically unsaturated monomer (α) and the monomer It is a copolymer containing a carbonyl group obtained by copolymerizing 70 to 99.9% by mass of an ethylenically unsaturated monomer (β) copolymerizable with the body (β).

  Examples of the carbonyl group-containing ethylenically unsaturated monomer (α) include diacetone acrylamide, diacetone methacrylamide, acrolein, vinyl methyl ketone, acetoacetoxyethyl methacrylate, acetoacetoxyethyl acrylate, formylstyrene, and combinations thereof. It is done.

  Examples of the ethylenically unsaturated monomer (β) copolymerizable with the monomer (α) include acrylic acid esters, methacrylic acid esters, ethylenically unsaturated monomers having a carboxyl group, and ethylene having an epoxy group. Unsaturated monomers, acrylamide monomers, methacrylamide monomers, vinyl cyanides and the like. Examples of (meth) acrylic acid esters include those having 1 to 18 carbon atoms in the alkyl moiety. (Meth) acrylic acid alkyl ester, (meth) acrylic acid hydroxyalkyl ester having 1 to 18 carbon atoms in the alkyl portion, (poly) oxyethylene (meth) acrylate having 1 to 100 ethylene oxide groups, propylene (Poly) oxypropylene (meth) acrylate having 1 to 100 oxide groups, 1 to 100 ethylene oxide groups (Poly) oxyethylene di (meth) acrylate etc. are mentioned.

  Specific examples of (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and methyl (meth) acrylate. Examples include cyclohexyl, cyclohexyl (meth) acrylate, dodecyl (meth) acrylate, adamantyl (meth) acrylate, and the like. Specific examples of the (meth) acrylic acid hydroxyalkyl ester include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxycyclohexyl (meth) acrylate, and dodecyl (meth) acrylate. Etc.

  Specific examples of (poly) oxyethylene (meth) acrylate include ethylene glycol (meth) acrylate, ethylene glycol methoxy (meth) acrylate, diethylene glycol (meth) acrylate, diethylene glycol methoxy (meth) acrylate, (meth) Examples include tetraethylene glycol acrylate and tetraethylene glycol methoxy (meth) acrylate.

  Specific examples of (poly) oxypropylene (meth) acrylate include propylene glycol (meth) acrylate, propylene glycol methoxy (meth) acrylate, dipropylene glycol (meth) acrylate, dipropylene glycol methoxy (meth) acrylate , (Meth) acrylic acid tetrapropylene glycol, methoxy (meth) acrylic acid tetrapropylene glycol, and the like. Specific examples of (poly) oxyethylene di (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, diethylene glycol methoxy (meth) acrylate, tetraethylene glycol di (meth) acrylate Etc.

  Specific examples of ethylenically unsaturated monomers having a carboxyl group include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, maleic acid half ester, and crotonic acid. Examples of monomers include (meth) acrylamide, N-methylol (meth) acrylamide, and N-butoxymethyl (meth) acrylamide. Examples of vinyl cyanides include (meth) acrylonitrile.

  Specific examples of the ethylenically unsaturated monomers having an epoxy group include glycidyl (meth) acrylate, 2,3-cyclohexene oxide (meth) acrylate, and allyl glycidyl ether.

  Specific examples of the ethylenically unsaturated monomer (β) copolymerizable with the monomer (α) other than the above include olefins such as ethylene, propylene and isobutylene, dienes such as butadiene, and vinyl chloride. , Haloolefins such as vinylidene chloride, vinyl acetate, vinyl propionate, vinyl n-butyrate, vinyl benzoate, vinyl pt-butylbenzoate, vinyl pivalate, vinyl 2-ethylhexanoate, vinyl versatate, laurin Carboxylic acid vinyl esters such as vinyl acid, isopropenyl acetate, isopropenyl carboxylic acid such as isopropenyl propionate, vinyl ethers such as ethyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether,

  Aromatic vinyl compounds such as styrene and vinyltoluene, allyl esters such as allyl acetate and allyl benzoate, allyl ethers such as allyl ethyl ether and allyl phenyl ether, and γ- (meth) acryloxypropyltrimethoxysilane, 4 -(Meth) acryloyloxy-2,2,6,6, -tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6,6, -pentamethylpiperidine, perfluoromethyl (meth) acrylate Perfluoropropyl (meth) acrylate, perfluoropropylmethyl (meth) acrylate, vinylpyrrolidone, trimethylolpropane tri (meth) acrylate, allyl (meth) acrylate, and the like, and combinations thereof.

  The polycarbonyl compound used in the present invention is preferably obtained by suspension polymerization, emulsion polymerization or solution polymerization because the resulting aqueous resin composition does not contain a large amount of organic solvent, and contains a carbonyl group obtained by emulsion polymerization. More preferably, it is an aqueous dispersion (emulsion).

  Furthermore, since the performance at the time of using the obtained aqueous resin composition as a coating material is favorable, a carbonyl group-containing acrylic copolymer dispersion using an acrylic monomer is preferable. Since the polycarbonyl compound is coated with the obtained aqueous resin composition and the water resistance of the obtained coating film is good, an ethylenically unsaturated monomer having a sulfonic acid group or a sulfonate group, a sulfate group is added. An emulsion obtained by copolymerization in the presence of an anionic ethylenically unsaturated monomer (γ) selected from the group consisting of ethylenically unsaturated monomers having a mixture thereof and mixtures thereof is preferred.

  Since the water resistance of the obtained coating film is good, the ethylenically unsaturated monomer having a sulfonic acid group or a sulfonate group has a radical polymerizable double bond and has a sulfonic acid group or a sulfonate group. A structure in which a part thereof is substituted with a group that is an ammonium salt, sodium salt, or potassium salt of a sulfonic acid group is preferable. Furthermore, it is selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkyl ether group having 2 to 4 carbon atoms, a polyalkyl ether group having 2 to 4 carbon atoms, an aryl group having 6 or 10 carbon atoms, and a succinic acid group. More preferably, it is a compound having a substituent. Further, a vinyl sulfonate compound having a vinyl group to which a group which is an ammonium salt, sodium salt or potassium salt of a sulfonic acid group is bonded is also preferable.

  The ethylenically unsaturated monomer having a sulfate ester group is a compound having a radical polymerizable double bond and having a sulfate ester group. Preferably, it is a compound partially substituted with a group that is an ammonium salt, sodium salt or potassium salt of a sulfate ester group, an alkyl group having 1 to 20 carbon atoms, an alkyl ether group having 2 to 4 carbon atoms, or a carbon number A compound having a substituent selected from the group consisting of 2 to 4 polyalkyl ether groups and aryl groups having 6 or 10 carbon atoms is more preferable.

  Specific examples of compounds having a succinic acid group partially substituted by a group that is an ammonium salt, sodium salt or potassium salt of a sulfonic acid group include allylsulfosuccinates, such as formulas (1), (2), ( 3) and compounds represented by (4).

{In Formulas (1) to (4), R ¹ is hydrogen or a methyl group, R ² is a cycloalkyl group having 5 to 12 carbon atoms, an aryl group having 5 to 10 carbon atoms, or an aralkyl having 6 to 19 carbon atoms. A hydrocarbon group such as a group, or one part thereof substituted with a hydroxyl group, a carboxylic acid group, or the like, or a polyoxyalkylene alkyl ether group (wherein the alkyl moiety has 0 to 20 carbon atoms (in the case of 0 carbon atoms, a hydrogen atom ), An alkylene moiety having 2 to 4 carbon atoms, a polyoxyalkylene alkylphenyl ether group (an alkyl moiety having 0 to 20 carbon atoms (a hydrogen atom in the case of 0 carbon atoms), an alkylene moiety having 2 to 4 carbon atoms) It is an organic group containing an alkylene oxide compound such as A is an alkylene group having 2 to 4 carbon atoms or an alkylene group substituent. n is an integer of 0-200. M is ammonium, sodium, or potassium. }
As what contains said Formula (1) and (2), there exists, for example, Eleminol JS-2 (brand name) (product made from Sanyo Chemical Co., Ltd.), and as what contains said Formula (3) and (4), for example, Latemuru S-120, S-180A or S-180 (trade name) (manufactured by Kao Corporation).

  Moreover, as an example of a compound having a C2-C4 alkyl ether group or a C2-C4 polyalkyl ether group partially substituted by a group which is an ammonium salt, sodium salt or potassium salt of a sulfonic acid group And compounds represented by formula (5) or (6).

(In the formula, each of R ³ and R ⁴ is independently an alkyl group, alkenyl group or aralkyl group having 6 to 18 carbon atoms, and R ⁵ is hydrogen or propenyl group. A is 2 to 4 carbon atoms. N is an integer of 1 to 200. M is ammonium, sodium or potassium.)

(In the formula, R ⁶ is hydrogen or a methyl group, R ⁷ is an alkyl group or acyl group having 8 to 24 carbon atoms, A is an alkylene group having 2 to 4 carbon atoms, and m is 0 to 20). And n is an integer from 0 to 50. M is ammonium, sodium or potassium.)
As an alkylphenol ether compound represented by the above formula (5), for example, there is Aqualon HS-10 (trade name) (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). As a compound represented by the above formula (6), for example, There is ADEKA rear soap SE-1025N (trade name) (manufactured by Asahi Denka Kogyo Co., Ltd.). Other specific examples of the compound having an aryl group partially substituted with a sulfonate group include ammonium salt, sodium salt and potassium salt of p-styrenesulfonic acid. Examples of a vinyl sulfonate compound having a vinyl group to which an ammonium salt, sodium salt or potassium salt of a sulfonic acid group is bonded include, for example, alkyl sulfonic acid (meth) acrylate such as 2-sulfoethyl acrylate and methylpropane sulfonic acid ( Examples thereof include ammonium salts such as (meth) acrylamide and allylsulfonic acid, sodium salts, and potassium salts.

  These anionic ethylenically unsaturated monomers (γ) are present in the emulsion as a copolymer obtained by radical polymerization into emulsion particles, adsorbed to the emulsion particles as unreacted materials, or present in the emulsion aqueous phase. Or adsorbed to the emulsion particles as a copolymer with a water-soluble monomer or a copolymer of monomers, or is present in the emulsion aqueous phase.

  In particular, the water resistance of the film obtained from the emulsion can be improved by increasing the ratio existing in the copolymerized state in which the emulsion particles are radically polymerized. The anionic ethylenically unsaturated monomer (γ) can be identified by pyrolysis gas chromatogram mass spectrometry (Py-GC-MS) or pyrolysis mass spectrometry (Py-MS) of a film obtained from the emulsion. it can. As another method, the aqueous phase component of the emulsion can be separated and then identified by fast atom bombardment mass spectrometry (FAB mass spectrum).

In the polymerization of the polycarbonyl compound emulsion, a normal surfactant can be used in combination with the anionic ethylenically unsaturated monomer (γ). For example, anionic surfactants such as fatty acid soaps, alkyl sulfonates, alkyl sulfosuccinates, polyoxyethylene alkyl sulfates, polyoxyethylene alkyl aryl sulfates, polyoxyethylene alkyl aryl ethers, polyoxyethylene sorbitan fatty acid esters , Non-reactive nonionic surfactants such as oxyethyleneoxypropylene block copolymers,
α- [1-[(allyloxy) methyl] -2- (nonylphenoxy) ethyl] -ω-hydroxypolyoxyethylene (trade names: Adeka Soap NE-20, NE-30, NE-40, etc., Asahi Denka Kogyo Reactive nonionic type such as polyoxyethylene alkylpropenyl phenyl ether (trade name: Aqualon RN-10, RN-20, RN-30, RN-50, etc., manufactured by Daiichi Pharmaceutical Co., Ltd.) Nonionic surfactants copolymerized with ethylenically unsaturated monomers called surfactants are used.

  In obtaining the polycarbonyl compound used in the present invention, the radical polymerization catalyst is a radical decomposition by heat or a reducing substance to cause addition polymerization of an ethylenically unsaturated monomer, which is water-soluble or oil-soluble. Persulfates, peroxides, azobis compounds and the like can be used. Examples include potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide, t-butyl hydroperoxide, t-butyl peroxybenzoate, 2,2-azobisisobutyronitrile, 2,2-azobis. There are (2-diaminopropane) hydrochloride, 2,2-azobis (2,4-dimethylvaleronitrile), and the amount is usually 0.1 to 1% by mass based on the ethylenically unsaturated monomer. Is done.

  Usually, it is preferably carried out at a polymerization temperature of 65 to 90 ° C. under normal pressure, but it can also be carried out under high pressure in accordance with characteristics such as vapor pressure at the polymerization temperature of the monomer. When acceleration of the polymerization rate and low temperature polymerization at 70 ° C. or lower are desired, it is advantageous to use a reducing agent such as sodium bisulfite, ferrous chloride, ascorbate, Rongalite in combination with the radical polymerization catalyst. It is. Further, in order to adjust the molecular weight, a chain transfer agent such as dodecyl mercaptan can be optionally added.

  In the aqueous resin composition of the present invention, in order to keep the polycarbonyl compound stable for a long period of time, it is preferably adjusted to a pH range of 5 to 10, and if necessary, ammonia, sodium hydroxide, potassium hydroxide, dimethylaminoethanol, etc. It is also possible to add acids such as hydrochloric acid, hydrochloric acid, sulfuric acid, acetic acid and lactic acid. In addition, examples of the polyepoxy compound that can be used in the aqueous resin composition of the present invention include other unsaturated monomers having an epoxy group-containing ethylenically unsaturated monomer such as glycidyl (meth) acrylate as an essential component. And copolymers containing epoxy groups obtained by copolymerization by bulk polymerization, suspension polymerization, emulsion polymerization, solution polymerization, etc., bisphenol A type epoxy resin, bisphenol F type epoxy resin, cyclic Examples include aliphatic epoxy resins, glycidyl ester epoxy resins, glycidyl amine epoxy resins, hydantoin type epoxy resins, triglycidyl isocyanurate and other epoxy compounds dispersed in water, and combinations thereof.

  In particular, the polyepoxy compound is preferably an epoxy group-containing acrylic copolymer aqueous dispersion. The epoxy group-containing acrylic copolymer aqueous dispersion can be produced in the same manner as the production of the carbonyl group-containing emulsion by selecting the monomer.

  The curable composition comprising the semicarbazide curing agent (A) of the present invention and the polycarbonyl compound (I) and / or the polyepoxy compound (U) has a solid mass ratio of (A) / ((I) + (U)) = 0.1 / 99.9 to 90/10 is preferable. Thus, a film having both low temperature curability and storage stability and excellent water resistance, stain resistance, hardness and the like can be provided. When this ratio is less than 0.1 / 99.9, the crosslinking density is lowered and the effect of crosslinking does not appear, which is not preferable. If it exceeds 90/10, the resulting film becomes very brittle, which is not preferable.

  In the composition of the present invention, monoketones represented by the formula (7) can be mixed for the purpose of controlling the reactivity with a polycarbonyl compound or a polyepoxy compound.

(Wherein R ⁸ and R ⁹ are each a hydrogen atom, a linear or branched aliphatic residue having 2 to 20 carbon atoms, an alicyclic residue having 5 to 20 carbon atoms, It represents at least one selected from an aromatic residue that may or may not have a substituent, and R ⁸ and R ⁹ may form a cyclic structure.
As monoketones represented by the formula (7), those having a relatively low boiling point of 30 to 200 ° C. (for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.) are preferable because the reactivity can be easily controlled.

  In addition, the aqueous resin composition of the present invention may be used in combination with a known ultraviolet absorber such as benzophenone, benzotriazole, or triazine, or a known light stabilizer such as a hindered phenol or hindered amine. In the water-based resin composition of the present invention, components that are usually added to and blended with paints as necessary, for example, pigments, fillers, dispersants, wetting agents, thickeners, rheology control agents, antifoaming agents, plasticizers, plasticizers, Film assistants, rust inhibitors, dyes, preservatives, and the like can be selected, combined and blended according to their respective purposes.

The aqueous resin composition of the present invention can be applied to a substrate to form a composite.
Examples of the base material to which the aqueous resin composition of the present invention is applied include non-metallic inorganic materials such as glass, gypsum and stone, metals such as iron, stainless steel, aluminum and copper, acrylic, polystyrene, polyester, polycarbonate, polyolefin and the like. Examples include molecules, synthetic rubber, natural rubber, cotton, silk, hemp, nylon and other fibers, and wood. You may apply | coat to these directly, and may apply | coat further, after apply | coating a coating material on these.

Hereinafter, the present invention will be described with reference to examples and comparative examples. As a method for quantifying the semicarbazide group, for example, 2 g of a semicarbazide curing agent is precisely weighed, placed in a 100 ml volumetric flask, made up to a constant volume with deionized water, weighed 10 ml, transferred to a 300 ml stoppered flask, and concentrated hydrochloric acid 3 Add 50 ml of hydrochloric acid prepared by mixing pure water 2 and titrate with 1/40 M potassium iodate solution, add 5 ml of chloroform near the end point, infiltrate vigorously, and titrate until the red color of the chloroform layer disappears. Can be obtained.
Semicarbazide group amount (mmol / g) = Titration (ml) / Semicarbazide curing agent amount (g) / 40

Moreover, the yellowing of the coating film by an alkaline solution can be inspected by measuring the color change after the coating film is immersed in a saturated calcium hydroxide solution for a predetermined period. The color change is measured by measuring the L ^* a ^* b ^* value using a MINOLTA color difference meter CR-200 before and after the test and calculating the change Δb ^* of the b ^* value before and after the test. Can do.

[Synthesis Example 1]
Preparation of polycarbonyl compounds.

  In a reactor having a reflux condenser, a dropping tank, a thermometer, and a stirrer, 218 g of ion exchange water, a 25% aqueous solution 3 of a surfactant (trade name: Adekaria Soap SE-1025N, manufactured by Asahi Denka Kogyo Co., Ltd.) 3 7 g was charged and the temperature in the reaction vessel was raised to 80 ° C., then 9 g of methacrylic acid, 4.5 g of styrene, 234 g of butyl acrylate, 13.5 g of diacetone acrylamide, 189 g of methyl methacrylate, 225 g, 14.4 g of Adeka Soap SE-1025N, 10 g of 25% aqueous solution of polyoxyethylene nonylphenyl ether (trade name: Emulgen 950, manufactured by Kao Corporation), and 1 g of ammonium persulfate were dropped into the reaction vessel. It was allowed to flow from the tank over 3 hours. During the inflow, the temperature in the reaction vessel was kept at 80 ° C. After completion of the inflow, the temperature in the reaction vessel was raised to 80 ° C. and kept for 2 hours. Thereafter, it is cooled to room temperature, adjusted to pH 8 by adding a 25% aqueous ammonia solution, filtered through a 100 mesh wire net, and a carbonyl group-containing copolymer aqueous emulsion having a solid content of 46.8% and an average particle size of 106 nm. Got.

[Example 1]
250 g of 80% hydrazine hydrate and 250 g of methanol were placed in a reaction group having a reflux cooling base, a thermometer, and a stirring device. Thereafter, 4500 g of methanol and 500 g of isophorone diisocyanate were added dropwise at room temperature over 1 hour while mixing with a static mixer. Then, after further stirring at room temperature for 1 hour, 400 g of dioxane was added, and methanol was removed under reduced pressure at a temperature of 30 ° C. or lower. After centrifuging for a while, a white powder was purified, which was filtered off and dried under vacuum at room temperature to obtain a semicarbazide curing agent (A). The amount of semicarbazide group of the obtained curing agent (a) was 6.2 mmol / g. 1.0 g of an aqueous solution of a semicarbazide curing agent (a) adjusted so that the semicarbazide group is 0.1 mmol / g, 5.0 g of ethylene glycol monobutyl ether and 1.0 g of a 1N sodium hydroxide aqueous solution were mixed, and at 20 ° C. After 24 hours, this mixed solution was put in a 1 cm square quartz cell, and the absorbance at 425 nm was measured and found to be 0.3. Further, a curing agent (A) was added to the polycarbonyl compound obtained in Synthesis Example 1 so that the semicarbazide group / carbonyl group in the polycarbonyl compound = 0.8, and a film was formed at room temperature. After immersing the film in a saturated calcium hydroxide aqueous solution for 1 week and observing a change in color difference, Δb ^* = 0.20.

[Example 2]
Semicarbazide curing prepared by adding 0.01 g of sodium dimethyldithiocarbamate (hereinafter referred to as SDD) to 1.0 g of the curing agent (a) obtained in Example 1 and adjusting the semicarbazide group to 0.1 mmol / g. 1.0 g of aqueous solution of the agent (a), 5.0 g of ethylene glycol monobutyl ether and 1.0 g of 1N sodium hydroxide aqueous solution were mixed and left at 20 ° C. for 24 hours, and then this mixed solution was put into a 1 cm square quartz cell. The absorbance at 425 nm was measured and found to be 0.2. Further, to the polycarbonyl compound obtained in Synthesis Example 1, an aqueous solution of the curing agent (a) to which the above-mentioned SDD was added so that the semicarbazide group / the carbonyl group in the polycarbonyl compound = 0.8 was added, The film was formed at room temperature. After immersing the film in a saturated calcium hydroxide aqueous solution for one week and observing a change in color difference, Δb ^* = 0.15.

[Comparative Example 1]
250 g of 80% hydrazine hydrate and 250 g of methanol were placed in a reaction group having a reflux cooling base, a thermometer, and a stirring device. Thereafter, 4500 g of methanol and 500 g of isophorone diisocyanate were added dropwise at room temperature over 1 hour while mixing with a static mixer. Then, after further stirring at room temperature for 1 hour, methanol and hydrazine were removed under reduced pressure at a temperature of 30-80 ° C. A white powder precipitated and was further vacuum dried at 80 ° C. to obtain a semicarbazide curing agent (I).

The amount of the semicarbazide group of the obtained curing agent (I) was 5.6 mmol / g. 1.0 g of an aqueous solution of a semicarbazide curing agent (ii) adjusted so that the semicarbazide group is 0.1 mmol / g, 5.0 g of ethylene glycol monobutyl ether and 1.0 g of 1N sodium hydroxide aqueous solution were mixed, and at 20 ° C. After 24 hours, this mixed solution was put into a 1 cm square quartz cell, and the absorbance at 425 nm was measured to be 1.7. Further, the curing agent (ii) was added to the polycarbonyl compound obtained in Synthesis Example 1 so that the semicarbazide group / carbonyl group in the polycarbonyl compound = 0.8, and a film was formed at room temperature. After immersing the film in a saturated aqueous calcium hydroxide solution for 1 week, the change in color difference was observed. As a result, Δb ^* = 3.0.

The semicarbazide curing agent of the present invention is useful as a raw material for water-based paints or the use of the curing agent.

Claims (7)

After mixing 1.0 g of a semicarbazide curing agent aqueous solution whose semicarbazide group was adjusted to 0.1 mmol / g, 5.0 g of ethylene glycol monobutyl ether, and 1.0 g of 1N sodium hydroxide aqueous solution, the mixture was placed at 20 ° C. for 24 hours, and then mixed. When the solution is placed in a 1 cm square quartz cell, the absorbance at 425 nm is 1.0 abs. A semicarbazide curing agent characterized by: The method for producing a semicarbazide curing agent according to claim 1, wherein the whole process for producing the semicarbazide curing agent is carried out at a temperature of 50 ° C or lower. 3. The method for producing a semicarbazide curing agent according to claim 2, wherein the step of producing the semicarbazide curing agent removes the solvent by crystallization. 4. The method for producing a semicarbazide curing agent according to claim 2, wherein the semicarbazide curing agent is synthesized by reacting isophorone diisocyanate and a hydrazine derivative. A semicarbazide curing agent, characterized in that the production method is any one of claims 2 to 4. An aqueous resin composition comprising the semicarbazide curing agent according to claim 1 or 5 and an aqueous resin. The composite_body | complex which apply | coated the water-system resin composition of Claim 6 to the base material.