JPH1150002A - Resin composition for water-based coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition, capable of forming a coating film good in low-temperature physical properties, weather resistance, hardness or the like and useful for coating the interior and exterior finish coating of buildings, bridges, vehicles or the like by including a hydrazine derivative in an emulsion polymer. SOLUTION: This resin composition for water-based coating materials is obtained by carrying out an emulsion polymerization of a polymerizable unsaturated monomer containing a carbonyl group-containing unsaturated monomer in the presence of water and an emulsifying agent using an unsaturated polyurethane resin obtained by reacting (a) a diisocyanate compound with (b) a polyol, (c) a carboxyl group-containing diol and (d) a hydroxyl group-containing ethylenically unsaturated monomer as a polymeric emulsifying agent in at least one stage of the emulsion polymerization of many stages and including (B) a hydrazine derivative having hydroxide group or semicarbazide group in an amount of 0.01-2 mol based on 1 mol carbonyl group in the component A as a cross-linking agent in the prepared emulsion polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for an aqueous coating material containing an aqueous polyurethane component and containing an emulsion polymer which can be obtained at a high solid content as a coating film forming component.

[0002]

2. Description of the Related Art In recent years, in the fields of paints, inks, adhesives, and the like, conversion from organic solvent type to aqueous has been promoted from the viewpoint of resource saving, environmental hygiene, no pollution, non-hazardous materials, and the like. I have. Generally, an acrylic copolymer emulsion is used as a vehicle component in an air-drying water-based paint.
According to the emulsion, a coating film having excellent weather resistance and hardness can be obtained, but there is a problem in water resistance and stain resistance. on the other hand,
In the market, needs such as coating film elasticity and toughness are increasing,
The use of a urethane resin in the cold aqueous paint is being studied. As a water-based paint having a urethane function, for example, a cold-setting water-based paint composed of a carbonyl group-containing water-based polyurethane resin and a hydrazide compound (Japanese Patent Publication No. 8-3019) has been proposed. According to the paint, a coating film having excellent water resistance and the like can be formed. However, since it is difficult to increase the solid content of the aqueous polyurethane resin, the composition as a whole has a low solid content. In addition, there was a problem in the coating workability, such as easy dripping. Further, in the known method of grafting urethane and acryl, it is difficult to increase the solid content of the resin due to limitations on the monomer composition and the ratio of urethane to acryl.

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, they have been produced by using a specific unsaturated polyurethane resin as an emulsifier component during one-stage emulsion polymerization of multiple stages. By using a high solids emulsion polymer as a film-forming component, the resulting water-based paint does not sag during the coating operation, and has both low-temperature properties of urethane resin and weather resistance and hardness of acrylic resin. The inventors have found that a coating film having an advantage is formed, and completed the present invention. The present invention relates to "1. An emulsion polymer produced by emulsion polymerization in a multi-stage process using a polymerizable unsaturated monomer in the presence of water and an emulsifier, wherein the polymerizable unsaturated monomer is Wherein at least one of the emulsion polymerizations is carried out by a diisocyanate compound (a), a polyol (b), a carboxyl group-containing diol (c) and a hydroxyl group-containing ethylenically unsaturated monomer. The emulsion polymer (I) produced using the unsaturated polyurethane resin obtained by the reaction with the monomer (d) as a polymer emulsifier has at least two or more hydrazide groups or semicarbazide groups per molecule as a crosslinking agent. Hydrazine derivative (I
Aqueous coating resin composition comprising (I) in a proportion of 0.01 to 2 moles of hydrazide group or semicarbazide group in component (II) with respect to 1 mole of carbonyl group contained in component (I). Stuff. 2. 2. The resin composition for an aqueous coating composition according to item 1, wherein the emulsion particles of the aqueous dispersion (I) of the emulsion polymer have a multilayer structure, at least one of which is a urethane graft copolymer layer. 3. 3. The resin composition for an aqueous coating composition according to item 1 or 2, wherein the unsaturated polyurethane resin is a polyurethane resin obtained by reacting an isocyanate group and a hydroxyl group in an equivalent ratio of 1: 1 to 1: 3. 4. An unsaturated polyurethane resin having a hydroxyl group-containing ethylenically unsaturated monomer (d) as a hydroxy compound;
The aqueous polyurethane resin composition according to any one of claims 1 to 3, wherein the unsaturated polyurethane resin is used in a ratio of 0.01 to 1 equivalent to 1 equivalent of isocyanate group. 5. When the unsaturated polyurethane resin has a number average molecular weight of 62 to
Item 5. The resin composition for water-based paint according to any one of Items 1 to 4, which is a polyurethane resin using 10,000 polyol (b). 6. (A), (b),
6. An unsaturated polyurethane resin obtained by reacting the components (c) and (d) in an organic solvent which is inert to isocyanate groups and has high affinity for water. The described resin composition for aqueous coatings. 7. The carbonyl group-containing unsaturated monomer is 0.1 to 30% by weight based on the total monomer weight used in the multistage;
Item 7. The resin composition for water-based paint according to any one of Items 1 to 6. 8. 9. The method according to any one of items 1 to 7, wherein the carbonyl group-containing unsaturated monomer is 1 to 50% by weight based on the total monomer weight used in the last stage of the multistage. A resin composition for an aqueous paint. 9. Item 9. The resin composition for an aqueous coating composition according to any one of Items 1 to 8, wherein the unsaturated polyurethane resin is a polyurethane resin having an acid value of 5 to 200 per gram of resin solid content. 10. 9. The polymerizable unsaturated monomer is a monomer mixture containing a (meth) acrylic monomer as a main component.
Item 14. The resin composition for a water-based paint according to any one of the above items. 11. 11. The aqueous paint resin composition according to any one of items 1 to 10, wherein the unsaturated polyurethane resin is blended in an amount of 0.1 to 50% by weight based on the total solid content of the emulsion polymer. About.

[0004]

BEST MODE FOR CARRYING OUT THE INVENTION The emulsion polymer (I) used in the present invention is produced by emulsion polymerization in a multi-stage process using a polymerizable unsaturated monomer in the presence of water and an emulsifier. A polymer which contains a carbonyl group-containing unsaturated monomer as the polymerizable unsaturated monomer and is produced using an unsaturated polyurethane resin during at least one stage of emulsion polymerization. The unsaturated polyurethane resin is a resin obtained by a reaction of a diisocyanate compound (a), a polyol (b), a carboxyl group-containing diol (c), and a hydroxyl group-containing ethylenically unsaturated monomer (d). In the production of a polymer, it is blended during at least one stage of emulsion polymerization in multiple stages and functions as a polymer emulsifier.

The diisocyanate compound (a) includes 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, m-phenylene diisocyanate, xylylene diisocyanate, tetramethylene diisocyanate, 2,2,4-trimethylhexane diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, 1,4-cyclohexylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, 3, 3'-dimethoxy-4,4'-biphenylenediisocyanate, 3,3'-dichloro-4,
4'-biphenylene diisocyanate, 1,5-naphthalene diisocyanate, 1,5-tetrahydronaphthalene diisocyanate, isophorone diisocyanate, and the like. Among these, aliphatic diisocyanates such as tetramethylene diisocyanate, 2,2,4-trimethylhexane diisodianate, hexamethylene diisocyanate, and lysine diisocyanate;
Preferred are alicyclic diisocyanates such as -cyclohexylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate and isophorone diisocyanate.

As the polyol (b), low molecular weight glycols, high molecular weight glycols, polyester polyols, polycarbonate polyols and the like may be used alone, and low molecular weight glycols may be used as polyester polyols and high molecular weight glycols. You may use together. The polyol (b) has a number average molecular weight of 62 to 10,
When the number average molecular weight is less than 62, the urethane soft portion disappears, and when the number average molecular weight is more than 10,000, handling during synthesis becomes difficult, which is not preferred.

[0007] Examples of the low molecular weight glycols include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, tetramethylene glycol, hexamethylene glycol, decamethylene glycol, octanediol, and tricyclohexane. There are decanemethylol, hydrogenated bisphenol A, cyclohexane dimethanol, bisphenol A polyethylene glycol ether, bisphenol A polypropylene glycol ether, and the like, and these may be used alone or as a mixture of two or more.

The high molecular weight glycols include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and the like. The polyester polyols include those obtained by reacting a glycol component with a dicarboxylic acid component. It can be easily produced and can be produced not only by the esterification reaction but also by a transesterification reaction. Also included are polyester diols obtained by a ring opening reaction of a cyclic ester compound such as ε-caprolactone and co-condensed polyesters thereof.

The carboxyl group-containing diols (c) include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolvaleric acid, and polyester polyols or polyether polyols obtained by condensing them. Is mentioned. Hydroxycarboxylic acids such as 12-hydroxystearic acid, paraoxybenzoic acid, 2,2-dimethyl-3-hydroxypropionic acid, and salicylic acid can be used in combination.

Examples of the hydroxyl group-containing ethylenically unsaturated monomer (d) include 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, and polyethylene glycol mono (meth) acrylate. , Polypropylene glycol-mono (meth) acrylate, 2-
Ε-caprolactone polyadduct of hydroxyethyl (meth) acrylate, β-methyl-δ-valerolactone polyadduct of 2-hydroxyethyl (meth) acrylate, glycerol mono (meth) acrylate, glycerol di (meth) acrylate, etc. Allyl compounds such as (meth) acrylates, allyl alcohol, glycerol monoallyl ether, and glycerol diallyl ether: and alkylene (C2-4) oxide adducts thereof (alkylene oxide is usually added in an amount of 0 to 30 mol; Preferably 10 to 20 mol).

The synthesis reaction of the above-mentioned unsaturated polyurethane resin may be carried out in an organic solvent, but dioxane, acetone, methyl ethyl ketone, methyl isobutyl ketone, N
-It is desirable to carry out the reaction in an organic solvent which is inert to isocyanate groups such as methylpyrrolidone and tetrahydrofuran and has a high affinity for water. In the synthesis of the unsaturated polyurethane resin, a monohydric alcohol may be blended, if necessary, for the purpose of blocking excess isocyanate groups in addition to the components (a), (b), (c) and (d). May be.
Although the proportions of these components (a), (b), (c) and (d) can be varied, the equivalent ratio of isocyanate groups to hydroxyl groups in all components is generally from 1: 1 to 1: 3. , Preferably 1: 1 to 1: 2.5. 1: 1
If it is smaller, the terminal becomes an isocyanate, which is not preferable for this purpose. If it is larger than 1: 3, an excessive amount of unreacted hydroxyl group component increases, and the emulsion stability at the time of producing an emulsion polymer is unpreferably reduced. The amount of the component (d) is 0.01 to 1 with respect to 1 equivalent of the isocyanate group.
Preferably it is 0.02-0.8 equivalent. If it is less than 0.01, the portion to be grafted is reduced, and the effect of improving the physical properties is poor. If it is more than 1, an excessive component (d) is generated, and the storage stability of the unsaturated polyurethane resin is undesirably reduced. .

The production of the unsaturated polyurethane resin is not particularly limited, but the components (a), (b), (c) and (d) may be reacted at once or in multiple stages. Production by a method, for example, by reacting a diisocyanate with a part of a polyol and a carboxyl group-containing diol to synthesize a prepolymer at an isocyanate terminal, and then reacting the remainder of the polyol with a hydroxyl group-containing ethylenically unsaturated monomer. May be. The reaction is usually performed at a temperature of 40 to 180 ° C, preferably 60 to 130 ° C. In order to promote this reaction, amine catalysts such as triethylamine, N-ethylmorpholine, and triethylenediamine used in ordinary urethanization reactions, and tin catalysts such as dibutyltin dilaurate and dioctyltin dilaurate may be used. . Further, in order to prevent the ethylenically unsaturated compound from being polymerized during the urethanization reaction, hydroquinone, hydroquinone monomethyl ether, p-benzoquinone and the like can be used. The acid value of the unsaturated polyurethane resin produced in this manner is 5 to 200 per 1 g of the solid content of the resin.
0 to 200 is preferred. Outside of this range, it is not desirable because it is difficult to dissolve or disperse in water, or when a coating is formed, the water resistance and the like are reduced.

[0013] The unsaturated polyurethane resin is dispersed in water. The aqueous dispersion can be carried out by a conventionally known method without any particular limitation. For example, while stirring water containing a neutralizing agent, a surfactant and the like as necessary, an unsaturated polyurethane resin is added and mixed and dispersed. Or continuously mixed. The neutralizing agent is not particularly limited as long as it can neutralize a carboxyl group. For example, sodium hydroxide, potassium hydroxide, trimethylamine, dimethylaminoethanol, 2-methyl-2-aminopropanol, triethylamine, ammonium, etc. Is mentioned. The neutralizing agent may be neutralized at the carboxyl group in addition to the resin, or may be added to water as a dispersion medium and neutralized simultaneously with the dispersion. Further, when an unsaturated polyurethane resin is used as an emulsifier during the production of an emulsion polymer described below, the unsaturated polyurethane resin may be simultaneously mixed and neutralized in the pre-emulsion. The amount used is 0.5-2.
The ratio is preferably 0, preferably 0.7 to 1.3 equivalents.

In the preparation of the emulsion polymer (I), emulsion polymerization is carried out in multiple stages using a polymerizable unsaturated monomer in the presence of water and an emulsifier, and at least one of the emulsion polymerizations is carried out. Is performed using the unsaturated polyurethane resin obtained as described above as a polymer emulsifier. As the multi-stage emulsion polymerization, specifically, first, a monomer mixture forming an internal layer component is subjected to a first-stage emulsion polymerization using a polymerization initiator in the presence of an emulsifier, and a polymer aqueous dispersion is obtained. After obtaining, in the aqueous dispersion, the monomer mixture forming the outer layer component, the emulsion polymerization of the second stage and subsequent steps using an emulsifier and a polymerization initiator may be sequentially performed in the same manner. An aqueous dispersion of emulsion polymer particles having a multilayer structure is obtained.

The polymerizable unsaturated monomer includes a carbonyl group-containing unsaturated monomer. Examples of the carbonyl group-containing unsaturated monomer include acrolein, diacetone acrylamide, and diacetone methacrylate. Examples include amides, formylstyrene, and vinyl alkyl ketones having 4 to 7 carbon atoms (eg, vinyl methyl ketone, vinyl ethyl ketone, vinyl butyl ketone), and the like. Of these, diacetone acrylamide and diacetone methacrylamide are particularly preferred. Further, the polymerizable unsaturated monomer may further include conventionally known ones, such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, Alkyl or cycloalkyl esters of (meth) acrylic acid having 1 to 24 carbon atoms, such as ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (meth) acrylate;
Hydroxyalkyl esters of (meth) acrylic acid having 2 to 8 carbon atoms such as 2-hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; vinyl aromatic compounds such as styrene and vinyl toluene; (meth) acrylic acid (Meth) acrylamide, maleic acid, crotonic acid, β-carboxyethyl acrylate, 2-acrylamide-2-methylpropanesulfonic acid, allylsulfonic acid, styrenesulfonic acid sodium salt, sulfoethylmethacrylate and its sodium salt and ammonium salt; Dimethylaminopropyl (meth) acrylamide, dimethylaminoethyl (meth) acrylate,
Adduct of glycidyl (meth) acrylate with amines; polyethylene glycol (meth) acrylate; N
-Vinylpyrrolidone, ethylene, butadiene, chloroprene, vinyl propionate, vinyl acetate, (meth) acrylonitrile, and the like, which are appropriately selected according to desired performance. In the production of the emulsion polymer (I), it is essential to use a carbonyl group-containing unsaturated monomer in at least one or more stages of the multistage polymerization, and the total weight of all the monomers used in the multistage is used. 0.1 to 30% by weight, preferably 1% by weight, of the carbonyl group-containing unsaturated monomer
10 to 10% by weight, and other polymerizable unsaturated monomers are 99.9%.
It is suitable to use so as to account for about 70% by weight, preferably 99% to 90% by weight. In particular, in the polymerization of the last stage of the multistage, the carbonyl group-containing unsaturated monomer is used in an amount of 1 to 50 with respect to the total weight of all the monomers used in that stage.
It is suitable to use it to account for 3% to 50% by weight, preferably 3 to 50% by weight.

Examples of the emulsifier include, in addition to the unsaturated polyurethane resin, an anionic surfactant, a nonionic surfactant, and the like. A polymerization initiator is used in the presence of one or more of the emulsifiers. To carry out emulsion polymerization. As the polymerization initiator, for example, known azo initiators such as azoisovaleronitrile, peroxides such as ammonium persulfate, potassium persulfate, and t-butyl hydroperoxide can be used. For the purpose of lowering, a reducing agent such as sodium formaldehyde sulfoxylate can be used.

In the emulsion polymer (I), the unsaturated polyurethane resin can be blended as a polymer emulsifier in any of the multiple stages of emulsion polymerization. It is preferable to mix them by emulsion polymerization in a stage. The unsaturated polyurethane resin is preferably blended in an amount of 0.1 to 50% by weight, preferably 1 to 50% by weight, based on the total solid content of the emulsion polymer (I). If the amount is less than 0.1% by weight, it is difficult to exhibit the properties of urethane. On the other hand, if it exceeds 50% by weight, it becomes difficult to synthesize an emulsion which is highly solidified. Further, in the emulsion polymerization at the stage of blending the unsaturated polyurethane resin as a polymer emulsifier, the polymerizable unsaturated monomer is contained in the total solid content of the unsaturated polyurethane resin and the polymerizable unsaturated monomer blended at that stage. It is preferable that the content of the body component is 5% by weight or more, preferably 10% by weight or more. If the amount is less than this, it becomes difficult to synthesize the emulsion, which is not preferable.

The aqueous dispersion of the emulsion polymer (I) produced as described above has emulsion particles having a multilayer structure,
At least one of them forms a urethane graft copolymer layer. In addition, since the multi-stage polymerization is used, there is an advantage that the range of selection of the polymerization component can be widened according to the purpose required for the emulsion particles. Therefore, it is possible to highly differentiate the whole emulsion while containing the urethane component. The hydrazine derivative (II) used in the present invention has at least two or more hydrazide groups or semicarbazide groups per molecule. Examples of the hydrazine derivative (II) include oxalic acid dihydrazide, malonic acid dihydrazide, and glutaric acid. Acid dihydrazide, succinic dihydrazide, adipic dihydrazide,
Saturated fatty acid carboxylic acid dihydrazide having 2 to 18 carbon atoms such as sebacic acid dihydrazide; monoolefinically unsaturated dicarboxylic acid dihydrazide such as maleic acid dihydrazide, fumaric acid dihydrazide, itaconic acid dihydrazide, phthalic acid, terephthalic acid or isophthalic acid Dihydrazide, and dihydrazide of pyromellitic acid,
Trihydrazide or tetrahydrazide; nitrilotrihydrazide, citric acid trihydrazide, 1,2,4-benzenetrihydrazide, ethylenediaminetetraacetic acid tetrahydrazide, 1,4,5,8-naphthoic acid tetrahydrazide, carboxylic acid lower alkyl ester group Polyhydrazide (see Japanese Patent Publication No. 52-22878) obtained by reacting a low polymer having the same with hydrazine or hydrazine hydrate (hydrazine hydride); dihydrazide carbonate, bissemicarbazide; diisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate; N,
N, N-substituted hydrazines such as N-dimethylhydrazine and polyfunctional semicarbazides obtained by excessively reacting the above-mentioned hydrazides, hydrophilicity such as polyisocyanate compounds and polyethers and polyols and polyethylene glycol monoalkyl ethers. Aqueous polyfunctional semicarbazide obtained by excessively reacting the above-mentioned dihydrazide with an isocyanate group in a reaction product with an active hydrogen compound containing a group, or a mixture of the polyfunctional semicarbazide and an aqueous polyfunctional semicarbazide (Japanese Patent Laid-Open Publication No. 151358, JP-A-8-283377 and JP-A-8-245878). The hydrazine derivative (II) is
The hydrazide group or the semicarbazide group in the hydrazine derivative (II) is 0.01 to 2 mol, preferably 0.05 to 1.5 mol, per 1 mol of the carbonyl group contained in the emulsion polymer (I). It is blended as follows. When the compounding ratio of the hydrazine derivative (II) is 0.01 mol terminal, a sufficient crosslinking effect cannot be obtained, and a problem of brittleness at the time of film formation occurs. Can not get. In producing a paint in the present invention, a pigment, a filler, an aggregate, a pigment dispersant, a wetting agent, an antifoaming agent, a plasticizer, a film-forming aid, an organic solvent, a preservative, a fungicide, and a pH adjuster , A rust inhibitor, a curing catalyst, etc., can be appropriately selected and combined according to the respective purposes.

[0019]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. Preparation of Unsaturated Polyurethane Resin In a four-neck flask with a capacity of 4 liters, place “Placcel 20
660 g of "5" (manufactured by Daicel Chemical Industries, Ltd., polycaprolactone diol), 111 g of dimethylolbutanoic acid, and 325 g of "Kyowanol D" (manufactured by Kyowa Hakko Co., Ltd., Texanol isobutyl ether) were added with stirring, and the temperature was raised to 80C. . When the mixture became homogeneous, 666 g of isophorone diisocyanate was added dropwise over 30 minutes. After the completion of the dropwise addition, the mixture is kept at 80 ° C. and the isocyanate value becomes 6
When it became 5 or less, 139 g of 2-hydroxyethyl acrylate was added. The temperature was kept at 80 ° C., and when the isocyanate value became 25 or less, 212 g of ethylene glycol was added. It is kept at 80 ° C. and cooled after the isocyanate value becomes 5 or less, and the solid content is 77% by weight.
Was obtained.

Production of Emulsion Polymer Aqueous Dispersion Production Example 1 348 g of deionized water in a 5 liter four-necked flask
0.6 g of “Newcol 707SF” (manufactured by Nippon Emulsifier Co., Ltd., an anionic surfactant having a polyoxyethylene chain, nonvolatile content of 30%) was added, and the temperature was maintained at 85 ° C. after nitrogen replacement. To this, 0.8 g of ammonium persulfate was added immediately before dropping a pre-emulsion having the following composition, and then the pre-emulsion was dropped over 3 hours. (1st stage) Deionized water 271 g Methyl methacrylate 300 g Styrene 105 g n-butyl acrylate 180 g 2-ethylhexyl acrylate 112 g Hydroxyethyl acrylate 15 g Newcol 707SF 50 g Ammonium persulfate 1.5 g 30 minutes after the end of dropping Then, it cooled to 75 degreeC. After a further 30 minutes, a pre-emulsion having the following composition was added dropwise thereto over 2 hours. (Second stage) Unsaturated polyurethane resin solution 130 g Methyl methacrylate 75 g n-butyl acrylate 67.5 g Diacetone acrylamide 7.5 g Triethylamine 5.1 g Ammonium persulfate 0.6 g Deionized water 373 g 30 minutes from the end of dropping Thereafter, a solution prepared by dissolving 0.5 g of ammonium persulfate in 40 g of deionized water was added dropwise thereto over 30 minutes. After dropping, add one more
47.1% by weight of solid content, viscosity of 17
An emulsion polymer emulsion (I-1) having cP, pH 6.7 and particle size of 251 nm was obtained.

Production Examples 2 to 4 The same operations as in Production Example 1 were carried out except that the monomers in the pre-emulsion at each stage of dropping were changed to the compositions shown in Table 1, and had the properties shown in Table 1. Emulsion polymer emulsions (I-2) to (I-4) were obtained.

[0022]

[Table 1]

Production Example 5 Deionized water 344 was placed in a five-liter four-necked flask.
g, “Newcol 707SF” (manufactured by Nippon Emulsifier Co., Ltd.,
An anionic surfactant having a polyoxyethylene chain,
4.5 g of 30% of non-volatile content), and after replacement with nitrogen, 70 ° C.
Kept. To this, 0.3 g of ammonium persulfate was added immediately before dropping a pre-emulsion having the following composition, and then the pre-emulsion was dropped over 2 hours. (First stage) Unsaturated polyurethane resin solution 130 g Methyl methacrylate 75 g n-butyl acrylate 68 g diacetone acrylamide 7.5 g triethylamine 5.1 g ammonium persulfate 0.6 g deionized water 373 g 30 minutes after the end of dropping , To 75 ° C. After a further 30 minutes, a pre-emulsion having the following composition was added dropwise thereto over 3 hours. (2nd stage) Deionized water 271 g Methyl methacrylate 300 g Styrene 105 g n-butyl acrylate 180 g 2-ethylhexyl acrylate 112 g Hydroxyethyl acrylate 15 g Newcol 707SF 50 g Ammonium persulfate 1.5 g 30 minutes after the end of the dropping Thereafter, a solution prepared by dissolving 0.5 g of ammonium persulfate in 40 g of deionized water was added dropwise thereto over 30 minutes. After dropping, add one more
47.5% by weight of solid content, viscosity of 12
An emulsion polymer emulsion (I-5) having 7 cP, pH 6.1, and a particle diameter of 118 nm was obtained.

Comparative Production Example 1 Deionized water 312 was placed in a four-neck flask having a capacity of 5 liters.
g, 2.3 g of Newcol 707SF, and the mixture was kept at 80 ° C. after nitrogen replacement. 0.7 g of ammonium persulfate was added thereto, and 15 minutes after the addition, a pre-emulsion having the following composition was added dropwise over 3 hours. Diacetone acrylamide 74 g Acrylic acid 3.6 g Styrene 105 g Methyl methacrylate 269 g 2-Ethylhexyl acrylate 105 g n-butyl acrylate 176 g Hydroxyethyl acrylate 15 g Newcol 707SF 49 g Ammonium persulfate 1.5 g Deionized water 315 g Dropping end After a lapse of 30 minutes, a solution prepared by dissolving 0.7 g of ammonium persulfate in 7 g of deionized water was added thereto.
It was added dropwise over 0 minutes. After completion of the dropwise addition, the temperature was further maintained at 80 ° C for 2 hours, and then the temperature was lowered to 40 to 60 ° C. Then, the pH was adjusted to 8 to 9 with aqueous ammonia to obtain an emulsion polymer emulsion (I-6) having a solid content of 55% by weight. The pH of the emulsion was 8.4.

Comparative Production Example 2 Deionized water 400 was placed in a four-neck flask having a capacity of 5 liters.
g, 20 g of Newcol 707SF, and the mixture was maintained at 70 ° C. after nitrogen replacement. A pre-emulsion having the following composition was dropped therein over 3 hours. Unsaturated polyurethane resin solution 130 g Methyl methacrylate 375 g n-butyl acrylate 247.5 g diacetone acrylamide 45.5 g styrene 105 g 2-ethylhexyl acrylate 113 g hydroxyethyl acrylate 15 g triethylamine 5.1 g ammonium persulfate 2.5 g deionized water After a lapse of 30 minutes from the completion of the dropping of 1000 g, a solution prepared by dissolving 1.25 g of ammonium persulfate in 80 g of deionized water was dropped therein over 30 minutes. After completion of the dropwise addition, the mixture was further kept at 70 ° C. for 1 hour to obtain an emulsion polymer emulsion having a solid content of 40.4% by weight, but the filtration residue was extremely large. The obtained emulsion polymer emulsion (I-7) had a viscosity of 4.1 cP, a pH of 7.2, and a particle diameter of 452 nm.

Preparation of Pigment Paste The following composition was blended in a 5-liter stainless steel container, and stirred with a stirrer for 20 to 40 minutes to prepare a pigment paste. Water 960 parts by weight Ethylene glycol 240 parts by weight Nopco Spars 44C (manufactured by San Nopco, a pigment dispersant) 60 parts by weight SN deformer 364 (manufactured by San Nopco, an antifoaming agent) 84 parts by weight Thickener) 36 parts by weight Titanium white 2640 parts by weight

Example 1 A stainless steel container having a capacity of 2 liters was charged with 1,000 parts by weight of the emulsion polymer emulsion (I-1) and 6.5 parts by weight of adipic dihydrazide, and the mixture was stirred.
1) was obtained. Next, 201 parts by weight of the pigment paste is placed in a stainless steel container having a capacity of 1 liter, and 475 parts by weight of the resin mixture (A-1) and 18 parts by weight of texanol are added with stirring, and the pH is adjusted to 7 to 9 with aqueous ammonia.
Paint (B-1) was obtained.

Examples 2 to 7 and Comparative Examples 1 and 2 Resin mixed liquids (A-2) to (A) were prepared in the same manner as in Example 1 except that the emulsion polymer emulsion and the adipic dihydrazide were blended as shown in Table 2. -7) and (A-9), (A-1)
0) was obtained. Next, a pigment paste and a resin mixture (A-
2) to (A-10), and paints (B-2) to (B-7), (B-9), and (B-10) were obtained in the same manner except that Texanol was used as shown in Table 3. .

Example 8 A stainless steel container having a capacity of 2 liters was charged with 1,000 parts by weight of the emulsion polymer emulsion (I-1) and 132 parts by weight of a semicarbazide compound solution (Note 1), and stirred to obtain a resin mixture (A- 8) was obtained. Next, 201 parts by weight of the pigment paste prepared in the above-described manner are placed in a stainless steel container having a capacity of 1 liter, and 475 parts by weight of the resin mixture (A-8) and 18 parts by weight of texanol are added with stirring. 9, to obtain a paint (B-8). The properties of each paint are shown in Table 3. (Note 1) Semicarbazide compound solution: “SX-60
1 ", manufactured by Asahi Kasei Corporation, semicarbazide group-containing compound,
Trade name, solid content 45%, butyl cellosolve / water (34 /
21) The solution, -NHCO-NHNH ₂ content 4.8 mmole / g resin.

[0030]

[Table 2]

[0031]

[Table 3]

Paint test 70 × 150 × 0.8mm “Esco” on both sides of the bond board
(Kansai Paint Co., Ltd., epoxy / amine-based rust-preventive undercoat) and left for 24 hours as a coated plate,
Each of the paints obtained as described above was coated on one side with water at 0 to 8%.
It was diluted and applied with a coating amount of 120 g / m ² by air spray. After drying for 2 hours, the same paint was further applied by air spray at a coating amount of 120 g / m ² . Each of the obtained test plates was subjected to the following tests. The results are shown in Table 4. (1) Water resistance test After coating the above test plate, drying it for 2 hours at a temperature of 20 ° C. and a relative humidity of 75%, half-submerge the test plate in 20 ° C. water, and after 1 hour, put the test plate The coated surface was pulled up and visually evaluated. ：: No change ：: Partial swelling △: Full swelling ×: Paint eluted (2) Water resistance test After coating the test plate, it was dried for 7 days at a temperature of 20 ° C and a relative humidity of 75%. After that, the test plate was half-submerged in 20 ° C. water, and after 5 days, the test plate was pulled up and the coated surface was visually evaluated. ◎: No change ○: Partial blistering △: Full blistering ×: Paint eluted (3) Accelerated weathering test After coating the above test plate, 7 days at 20 ° C and 75% relative humidity After drying, a 1,500-hour weather resistance test was performed using a sunshine weatherometer to calculate the gloss retention.

[0033]

(Equation 1)

(4) Two-cone hardness test Each paint was applied to a glass plate with a 6-mil blade, dried at room temperature for 10 days, and the two-cone hardness was measured. The higher the value, the harder it is. (5) JIS A 6910 waterproofing standard-related test Elongation test "Ales rubber tile rough" (manufactured by Kansai Paint Co., Ltd.
After 24 hours, each coating material was applied with a brush to a thickness of 100 g / m ² on a plate coated with a 2 mm blade. After another 2 hours, the same paint was applied again. Thereafter, the test piece was cured according to the standard of JIS A 6910, punched out with a No. 2 dumbbell, used as a test piece, and subjected to an elongation test at 20 ° C. and −10 ° C. Heating / cooling repetition test Using Ares rubber tile sealer (manufactured by Kansai Paint Co., Ltd., sealer) as a primer, Ares rubber tile rough and each paint were further applied in the same manner as above to prepare test pieces. According to the JIS A 6910 repetition test of warm and cool, <Immersion in water for 18 hours to 3 hours in a -20 ° C. incubator to 5 hours in a 50 ° C. incubator>
The state of the coating film surface after the 15-cycle test was visually evaluated. ◎: No abnormality in coating film ○: Swelling in part of coating film △: Swelling in entire coating film ×: Cracking in coating film (6) Coating workability Each coating material was diluted with tap water to have a viscosity of 68. JIS on a 300 x 450 x 0.8 tin plate that has been adjusted to ~ 70 KU and degreased
With the roller brush of the medium hair specified in S 9024,
After coating at a coating amount of 115 to 125 g / m ^2, the coated plate was quickly erected vertically. After drying at room temperature for 16 to 24 hours, the sagging property and skin of the coating film surface were visually evaluated. (Sagging properties) ：: No sagging is observed. ○: Slight sagging is observed. Δ: Clear sagging is observed, even at a distance of 5 m. ×: Films are entirely sagged on the upper and lower parts of the coated plate. Very large difference in thickness (skin) ：: Both skin and gloss are good ○: Roller grain is slightly recognized but gloss is good △: Roller grain is not recognized but gloss is low ×: Sagging is not severely evaluated

[0035]

[Table 4]

[0036]

According to the present invention, the emulsion particles have a multilayer structure, and at least one of them forms a urethane graft copolymer layer. Since the emulsion polymer produced as a vehicle component is used as a vehicle component, a water-based paint containing it can provide good coating workability, and has the advantages of both low-temperature properties of urethane and weather resistance and hardness of acrylic. An effect of forming a coating film exhibiting a good balance is exhibited. Therefore, the composition of the present invention is particularly useful for painting interior / exterior buildings, bridges, ships and vehicles.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masami Sugishima 4-171-1, Higashi-Yawata, Hiratsuka-shi, Kanagawa Prefecture Inside Kansai Paint Co., Ltd. (72) Inventor Nobuto Hirata 4-171-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Nishi Paint Co., Ltd.

Claims (11)

[Claims] 1. An emulsion polymer produced by multi-stage emulsion polymerization using a polymerizable unsaturated monomer in the presence of water and an emulsifier, wherein the polymerizable unsaturated monomer is carbonyl. A diisocyanate compound (a) containing a group-containing unsaturated monomer, and at least one of the emulsion polymerization steps,
Polyol (b), carboxyl group-containing diol (c)
And hydroxyl group-containing ethylenically unsaturated monomer (d)
Polymer (I) produced using an unsaturated polyurethane resin obtained by the reaction with
In addition, a hydrazine derivative (II) having at least two or more hydrazide groups or semicarbazide groups per molecule as a cross-linking agent is one of the carbonyl groups contained in the component (I).
A resin composition for water-based paints, wherein the hydrazide group or the semicarbazide group in the component (II) is blended in an amount of 0.01 to 2 mol per mol. 2. The resin for water-based paint according to claim 1, wherein the emulsion particles of the aqueous dispersion (I) of the emulsion polymer have a multilayer structure, at least one of which is a urethane graft copolymer layer. Composition. 3. The resin for water-based paint according to claim 1, wherein the unsaturated polyurethane resin is a polyurethane resin obtained by reacting an isocyanate group and a hydroxyl group in an equivalent ratio of 1: 1 to 1: 3. Composition. 4. An unsaturated polyurethane resin comprising a hydroxyl group-containing ethylenically unsaturated monomer (d) as a hydroxy compound in an amount of from 0.01 to 1 equivalent of an isocyanate group.
An unsaturated polyurethane resin used in a ratio of 1 equivalent,
The resin composition for a water-based paint according to any one of claims 1 to 3. 5. The resin for water-based paints according to claim 1, wherein the unsaturated polyurethane resin is a polyurethane resin using a polyol (b) having a number average molecular weight of 62 to 10,000. Composition. 6. An unsaturated polyurethane resin comprising: (a)
6. An unsaturated polyurethane resin obtained by reacting the components (b), (c) and (d) in an organic solvent which is inert to isocyanate groups and has high affinity for water.
The resin composition for a water-based paint described in any one of the above. 7. The carbonyl group-containing unsaturated monomer is used in an amount of 0.1 to 30% by weight based on the total weight of the monomers used in multiple stages.
The resin composition for a water-based paint according to any one of claims 1 to 6, which is: 8. The unsaturated monomer having a carbonyl group may be used in an amount of 1 to 1 based on the total weight of the monomers used in the last stage of the multistage.
The resin composition for a water-based paint according to any one of claims 1 to 7, which is 50% by weight. 9. The resin composition for water-based paints according to claim 1, wherein the unsaturated polyurethane resin is a polyurethane resin having an acid value of 5 to 200 per gram of resin solid content. 10. The aqueous coating composition according to claim 1, wherein the polymerizable unsaturated monomer is a monomer mixture containing a (meth) acrylic monomer as a main component. Resin composition. 11. The water-based coating composition according to claim 1, wherein the unsaturated polyurethane resin is incorporated in an amount of 0.1 to 50% by weight based on the total solid content of the emulsion polymer. Resin composition.