JPH10259356A - Resin composition for water-base coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin compsn. for a water-base coating material capable of forming a coating film excellent in weatherability, water resistance, and durability. SOLUTION: This compsn. comprises 100 pts.wt. (solid content basis) water- base carbonylated copolymer dispersion (A), 5-500 pts.wt. water-base carbonylated graft urethane resin (B) obtd. by copolymerizing 0.01-40 wt.% carbonylated ethylenically unsatd. monomer and 10-97.99 wt.% other polymerizable unsatd. monomer in the presence of 2-50 wt.% unsatd. polyurethane resin, and a hydrazine deriv. (C) having at least two hydrazide or semicarbazide groups molecule as the cross-linker in such an amt. that the molar ratio of the hydrazide or semicarbazide group in ingredient C to the carbonyl group in ingredients A and B is 0.01-2.

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 a water-based paint capable of forming a coating film having excellent weather resistance, water resistance, and durability. The present invention relates to a cold-crosslinkable water-based paint resin composition suitable for painting vehicles and the like.

[0002]

2. Description of the Related Art Conventionally, an aqueous dispersion of an acrylic copolymer has been mainly used for an air-drying type water-based paint used for applications such as interior and exterior of buildings. According to the paint, a coating film excellent in weather resistance and hardness can be obtained, but there are problems in water resistance, stain resistance, and the like. On the other hand, in the market, needs such as coating film elasticity and toughness are increasing, and the use of urethane resins for the normally-dry type aqueous coating 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, for example, it became easy to sag. On the other hand, a paint comprising an aqueous dispersion of a carbonyl group-containing copolymer, an aqueous carbonyl group-containing polyurethane resin and a hydrazide compound (JP-A-7-113)
No. 061). The paint has no problem in coating workability and can provide a coating film having excellent water resistance and durability. However, the advantages of each of the acrylic and urethane components in terms of weather resistance, hardness, low-temperature properties, etc. have not yet been fully exerted.

[0003]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, a urethane graft resin component having a carbonyl group-containing copolymer as a trunk and polyurethane as a branch component has been used as an acrylic resin component. The present inventors have found that by using them together, it is possible to obtain a highly functional coating film having well-balanced performance such as weather resistance and hardness by acrylic and low-temperature physical properties by urethane, and have reached the present invention.

The present invention relates to the following: 1. An aqueous dispersion of a carbonyl group-containing copolymer (A)
2 to 50% by weight of an unsaturated polyurethane resin, 0.01 to 40% by weight of an ethylenically unsaturated monomer having a carbonyl group, and 10 to 97.9% by weight of another polymerizable unsaturated monomer. The carbonyl group-containing aqueous urethane graft resin (B) obtained by copolymerization at a ratio of 5 to 500 parts by weight with respect to 100 parts by weight of the solid content of (A) is blended. The hydrazine derivative (C) having two or more hydrazide groups or semicarbazide groups is prepared by converting the hydrazide group or semicarbazide group in the component (C) to 0 with respect to 1 mol of the carbonyl group contained in the components (A) and (B). A resin composition for a water-based paint, which is blended so as to be 0.12 to 2 mol. 2. The carbonyl group-containing copolymer aqueous dispersion (A) is
(A) 0.1 to 30% by weight of a polymerizable unsaturated monomer having at least one carbonyl group in one molecule, and (b) a water-soluble ethylenic monomer copolymerizable with the monomer (a). A monomer mixture containing 0 to 10% by weight of a saturated monomer and (c) 60 to 99.9% by weight of another ethylenically unsaturated monomer is obtained by emulsion polymerization in the presence of an emulsifier. 2. The resin composition for an aqueous coating composition according to item 1, which is an aqueous dispersion of a copolymer. 3. An unsaturated polyurethane resin comprising a diisocyanate compound (d) and a polyol (e) having a number average molecular weight of 62 to 10,000, a carboxyl group-containing diol (f) and a hydroxyl group-containing ethylenically unsaturated monomer (g) 3. The resin composition for water-based paint according to item 1 or 2, which is a resin obtained by a reaction. 4. The resin for water-based paint according to any one of claims 1 to 3, wherein the unsaturated polyurethane resin is a polyurethane resin obtained by reacting isocyanate groups and hydroxyl groups at an equivalent ratio of 1: 1 to 1: 3. Composition. 5. The unsaturated polyurethane resin is a hydroxyl group-containing ethylenically unsaturated monomer as a hydroxy compound (g)
5. The resin composition for an aqueous coating composition according to any one of items 1 to 4, wherein is used in a ratio of 0.1 to 1 equivalent to 1 equivalent of isocyanate group. 6. 1 g of solid content of unsaturated polyurethane resin
Item 6. The resin composition for water-based paint according to any one of Items 1 to 5, which is a resin having an acid value of 0 to 200. 7. The carbonyl group-containing aqueous urethane graft resin (B) is obtained by using an unsaturated polyurethane resin as a polymer emulsifier to form a carbonyl group-containing ethylenically unsaturated monomer (h) and another polymerizable unsaturated monomer (i). 7. The resin composition for an aqueous paint according to any one of items 1 to 6, which is a resin obtained by emulsion polymerization of 8. The carbonyl group-containing aqueous urethane graft resin (B) contains 2 to 50% by weight of an unsaturated polyurethane resin,
0.1% of the carbonyl group-containing ethylenically unsaturated monomer (h) is used.
01 to 40% by weight, water-soluble ethylenically unsaturated monomer (j) 0 to 10% by weight, other polymerizable unsaturated monomer (i)
8. The aqueous resin composition for application according to any one of items 1 to 7, wherein the resin is a resin obtained by copolymerizing the resin at a ratio of 0 to 99.99% by weight. About.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the mixing ratio of the carbonyl group-containing copolymer aqueous dispersion (A) and the carbonyl group-containing aqueous urethane graft resin (B) is based on 100 parts by weight of the solid content of (A). On the other hand, if (B) is 5 to 500 parts by weight, preferably 10 to 400 parts by weight, and if (B) is less than 5 parts by weight, the effect of improving the physical properties is poor, and if it exceeds 500 parts by weight, the solid content of the coating material decreases. It is not preferable because the coating workability is reduced.

The amount of the hydrazine derivative (C) added is
The amount of the hydrazide group or semicarbazide group is 0.01 to 1 mol of the carbonyl group in the components (A) and (B).
To 2.0 mol, preferably 0.05 to 1.5 mol. If the amount is less than 0.01 mol, a sufficient crosslinking effect cannot be obtained, and a problem of fragility at the time of film formation occurs,
If the amount is more than 2.0 mol, it is not possible to obtain an effect exceeding the desired crosslinking effect.

Aqueous dispersion of carbonyl group-containing copolymer (A)
Examples of the monomer (a) which forms are: acrolein, diacetone acrylamide, diacetone methacrylamide, acetoacetoxyethyl methacrylate,
Formyl styrene, vinyl alkyl ketone having 4 to 7 carbon atoms (for example, vinyl methyl ketone, vinyl ethyl ketone, vinyl butyl ketone) and the like.
Of these, diacetone acrylamide and diacetone methacrylamide are particularly preferred.

The monomer (b) is a monomer which can be copolymerized with the monomer (a) and shows a strong hydrophilicity by itself or by neutralization or quaternary salification. Any of nonionic and nonionic monomers may be used. As the monomer (b), in the anionic system,
(Meth) acrylic acid, maleic acid, crotonic acid, β-carboxyethyl acrylate, 2-acrylamide-2
-Methylpropanesulfonic acid, allylsulfonic acid, styrenesulfonic acid sodium salt, sulfoethyl methacrylate and its sodium salt and ammonium salt and the like; in the case of cationic systems, for example, (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, dimethylaminoethyl ( (Meth) acrylates, furthermore, adducts of glycidyl (meth) acrylate with amines, and the like; (non-method) include (meth) acrylates having a polyoxyethylene chain.

The monomer (c) includes, for example, methyl (meth) acrylate, ethyl (meth) acrylate,
Propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, lauryl (meth)
C1-C24 alkyl or cycloalkyl esters of (meth) acrylic acid such as acrylate and isobornyl (meth) acrylate; (meth) acrylic acid such as 2-hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate Hydroxyalkyl esters having 2 to 8 carbon atoms; vinyl aromatic compounds such as styrene and vinyl toluene; N-vinylpyrrolidone, ethylene, butadiene, chloroprene, vinyl propionate, vinyl acetate (meth) acrylonitrile, and the like. Are appropriately used depending on the desired performance.

The above-mentioned copolymer can be obtained by a known method. For example, it can be easily obtained by subjecting the above monomer component to emulsion polymerization in the presence of an emulsifier. Examples of the emulsifier include anionic surfactants and nonionic surfactants. Emulsion polymerization can be performed using a polymerization initiator in the presence of one or more of the emulsifiers. Known suspension polymerization or the like may be employed other than emulsion polymerization.

The proportions of the monomers (a), (b) and (c) used for forming the aqueous dispersion of the carbonyl group-containing copolymer are (a) 0.1 to 30% by weight, (b) ) 0 to 10% by weight and (c) 60 to 99.9% by weight, and an aqueous dispersion can be produced by emulsion-polymerizing this monomer mixture in the presence of an emulsifier. When the amount of the monomer (a) is 0.
If the amount is less than 1% by weight, a sufficient crosslinking effect cannot be obtained, and a problem of brittleness at the time of film formation occurs, which is not preferable. 30% by weight
Even if it is larger, the desired crosslinking effect cannot be obtained more than the desired effect, so 0.1 to 30% by weight is preferable. If the amount of the monomer (b) is more than 10% by weight, the water resistance of the coating film obtained is undesirably reduced. When the amount of the monomer (c) is less than 60% by weight, the water resistance of the coating film obtained is reduced. When the amount is more than 99, 9% by weight, a sufficient crosslinking effect cannot be obtained, and the brittleness during film formation is not obtained. Problems occur and are not preferred.

The aqueous carbonyl group-containing urethane graft resin (B) used in the present invention is obtained by copolymerizing an unsaturated polyurethane resin, a carbonyl group-containing ethylenically unsaturated monomer and another polymerizable unsaturated monomer. It is obtained. Usually, in the presence of an emulsifier, an unsaturated polyurethane resin, a carbonyl group-containing unsaturated monomer and other polymerizable unsaturated monomers are emulsion-polymerized, and in particular, an unsaturated polyurethane resin is used as an emulsifier component. It is preferred that the monomers are emulsion polymerized.

The unsaturated polyurethane resin constitutes a branch portion of the graft resin (B), and can also act as a polymer emulsifier in the synthesis of the resin (B). Examples of the unsaturated polyurethane resin include a diisocyanate compound (d), a polyol (e) having a number average molecular weight of 62 to 10,000, a carboxylic group-containing diol (f), and a hydroxyl group-containing ethylenically unsaturated monomer (g). ) Can be used. When the polyol (e) has a number average molecular weight of less than 62, the physical properties of the coating film deteriorate, and the
If the value is larger than 00, it is not preferable because the handling at the time of synthesis becomes difficult.

As the diisocyanate (d),
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'-biphenylene diisocyanate , 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 diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate;
Preferred are alicyclic diisocyanates such as 4-cyclohexylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and isophorone diisocyanate.

As the polyols (e), low molecular weight glycols, high molecular weight glycols, polyester polyols, polycarbonate polyols and the like may be used alone, and polyester polyols and high molecular weight glycols may be replaced with low molecular weight glycols. May be used together. Examples of 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 tricyclodecane dimethylol. , Hydrogenated bisphenol A, cyclohexane dimethanol, bisphenol A polyethylene glycol ether, bisphenol A
There are polypropylene glycol ether and the like, and these may be used alone or in combination of two or more. Examples of the high molecular weight glycols include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and the like, and examples of the polyester polyols include those obtained by reacting a glycol component and a dicarboxylic acid component. It can be 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.

Examples of the carboxyl group-containing diol (f) include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolvaleric acid, and polyester polyols or polyether polyols obtained by condensing these. Can be 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 (g) include 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, and polyethylene glycol mono (meth). Acrylate, 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,
(Meth) acrylates such as glycerol mono (meth) acrylate and glycerol di (meth) acrylate; allyl compounds such as allyl alcohol, glycerol monoallyl ether and glycerol diallyl ether; and alkylene (2-4 carbon) oxide additions thereof (The addition mole number of the alkylene oxide is usually 0 to 3).
0 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 2
-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 is blended, if necessary, for the purpose of blocking excess isocyanate groups, in addition to the above-mentioned components (d), (e), (f) and (g). You may. Although the proportions of these components (d), (e), (f) and (g) can be varied, the equivalent ratio of isocyanate groups to hydroxyl groups in all components is generally 1: 1 to 1:
3, preferably 1: 1 to 1: 2.5.
If the ratio is less than 1: 1, the terminal becomes an isocyanate group, which is not preferred for the purpose of the present invention. If the ratio is more than 1: 3, an excess of unreacted hydroxyl group components increases, and the stability of the emulsion synthesized in the next step is lowered, which is not preferable. The amount of the component (g) is 0.01 to 1, preferably 0.02 to 0.8 equivalent per equivalent of isocyanate group. If it is less than 0.01, the portion to be grafted will be small, and the effect of improving the physical properties will be poor. If it is more than 1, an excessive amount of the (g) component will undesirably lower the storage stability of the unsaturated polyurethane resin.

The production of the above-mentioned unsaturated polyurethane resin is not particularly limited, but the above-mentioned (d), (e), (f),
And the component (g) may be reacted at once, or may be reacted in a multistage manner (a reaction of a diisocyanate with a part of the polyol and a carboxyl group-containing diol to synthesize a prepolymer at an isocyanate terminal, The remaining residue is reacted with a hydroxyl group-containing ethylenically unsaturated monomer). 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, and tin catalysts such as dibutyltin dilaurate and dioctyltin dilaurate used in a usual urethanization reaction are used. Is also good. 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 thus produced is preferably from 10 to 200 per gram of resin solids.
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 decrease.
The unsaturated polyurethane resin is dispersed in water. Aqueous dispersion can be performed by a conventionally known method without any particular limitation,
For example, it is possible to add and mix and disperse an unsaturated polyurethane resin while stirring water containing a neutralizing agent, a surfactant and the like as necessary, or to mix continuously.

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 , Ammonia and the like. 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. The amount used is preferably 0.5 to 2.0, preferably 0.7 to 1.3 equivalents, per equivalent of the carboxyl group. The solid content concentration of the aqueous dispersion of unsaturated polyurethane resin thus obtained is usually from 20 to
50% by weight, viscosity in the range of 5 to 5000 mPa (25 ° C.).

In the carbonyl group-containing aqueous polyurethane resin (B), the carbonyl group-containing ethylenically unsaturated monomer (h) copolymerized with the unsaturated polyurethane resin described above.
And the other polymerizable unsaturated monomer (i) constitutes the backbone of the graft resin (B), and the carbonyl group-containing ethylenically unsaturated monomer (h) includes The monomer exemplified in the description of the carbonyl group-containing α, β-ethylenically unsaturated monomer (a) used in the group-containing copolymer aqueous dispersion (A) can be used. Examples of the polymerizable unsaturated monomer (i) include the water-soluble ethylenically unsaturated monomer (b) used in the aqueous carbonyl group-containing copolymer aqueous dispersion (A) and other ethylenically unsaturated monomers. Any of the monomers exemplified in the description of the monomer (c) can be appropriately selected and used.

The production of the graft resin (B) is usually carried out by
It is easily obtained by subjecting the above components to emulsion polymerization in the presence of an emulsifier. As an emulsifier, an anionic surfactant,
Nonionic surfactants and the like can be mentioned. In particular, the above-mentioned unsaturated polyurethane resin can be used as a polymer emulsifier, whereby the amount of a normal emulsifier can be reduced.
The above monomers can be emulsion-polymerized using a polymerization initiator in the presence of one or more of the emulsifiers. As the polymerization initiator, for example, known azo initiators such as azoisovaleronitrile, ammonium persulfate, potassium persulfate, and persulfides such as t-butyl hydroperoxide can be used. A reducing agent such as sodium formaldehyde sulfoxylate can also be used for the purpose of lowering the concentration. In addition to known emulsion polymerization, known suspension polymerization and the like may be employed.

The amount of each component used in the synthesis of the resin (B) is 2 to 50% by weight, preferably 5 to 45% by weight, of the unsaturated polyurethane resin, 0.01 to 0.01% of the carbonyl group-containing ethylenically unsaturated monomer. 40% by weight, preferably 1-30
% By weight, 10 to 97.9% by weight, preferably 25 to 94% by weight of other polymerizable unsaturated monomers. Further, from the viewpoint of the stability of the emulsion, when the water-soluble ethylenically unsaturated monomer (j) is contained as another polymerizable unsaturated monomer, the water-soluble ethylenically unsaturated monomer in the above total amount may be used. From 0 to 10% by weight, preferably from 0.1 to 5% by weight.
% By weight, and 0-97.9 other polymerizable unsaturated monomers.
It is desirable to use 9% by weight, preferably 5 to 97.89% by weight, and a total of 10 to 99.99% by weight. If the amount of the unsaturated polyurethane resin is less than 2% by weight, the physical properties of the coating film at low temperatures are reduced, while if it exceeds 50% by weight, the compatibility with the resin (A) is reduced, and the weather resistance of the obtained coating film is reduced. In addition, the amount of the carbonyl group-containing ethylenically unsaturated monomer to be used is less than 0.1.
If the amount is less than 01% by weight, sufficient cross-linking and curing cannot be obtained, while if it exceeds 40% by weight, the storage stability of the coating material is undesirably reduced. If the amount of the other monomer is less than 10% by weight, the compatibility with the resin (A) is reduced, which adversely affects the weather resistance and physical properties of the obtained coating, and if it is more than 97.99% by weight, the obtained coating is The effect of improving the physical properties is poor, which is not preferred.

The hydrazine derivative (C) used in the present invention has at least two or more hydrazide groups or semicarbazide groups per molecule. Examples of the hydrazine derivative (C) include oxalic acid dihydrazide and malonic acid dihydrazide. , Glutaric dihydrazide,
Saturated aliphatic carboxylic acid dihydrazide having 2 to 18 carbon atoms such as succinic acid dihydrazide, adipic acid dihydrazide, 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, trihydrazide or tetrahydrazide of pyromellitic acid; nitrilotriacetic acid trihydrazide, citric acid trihydrazide, 1,2,4
Reaction of benzenetrihydrazide, ethylenediaminetetraacetic acid tetrahydrazide, 1,4,5,8-naphthoic acid tetrahydrazide, a low polymer having a carboxylic acid lower alkyl ester group with hydrazine or hydrazine hydrate (hydrazine hydrate); Polyhydrazide (see Japanese Patent Publication No. 22228/1972); carbonic acid dihydrazide, bissemicarbazide; excessive reaction of dihydrazine compound or the above-mentioned dihydrazide with diisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate and polyisocyanate compounds derived therefrom. Active hydrogen compound containing hydrophilic group such as polyfunctional semicarbazide, polyisocyanate compound and polyether polyols or polyethylene glycol monoalkyl ethers Reaction in aqueous polyfunctional semicarbazide obtained by overreact exemplified above dihydrazide isocyanate groups with, or a mixture of polyfunctional semicarbazide and aqueous polyfunctional semicarbazide (JP 8-
151358, and JP-A-8-245878).

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, p
An H adjuster, a rust preventive, and the like can be selected and combined according to each purpose.

[0027]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. Production of Copolymer Emulsion (A) Production Example 1 312 parts by weight of deionized water, Newcol 707SF (manufactured by Nippon Emulsifier Co., anionic surfactant having a polyoxyethylene chain, nonvolatile content of 30) was placed in a two-liter four-neck flask. %) 2.3 parts by weight, and after replacement with nitrogen, 80 ° C.
Kept. 0.7 parts by weight of ammonium persulfate was added thereto, and 15 minutes after the addition, a pre-emulsion obtained by emulsifying the following composition was added dropwise over 3 hours. Deionized water 338 parts by weight Diacetone acrylamide 32 parts by weight Acrylic acid 3.2 parts by weight Styrene 97 parts by weight Methyl methacrylate 260 parts by weight 2-ethylhexyl acrylate 100 parts by weight n-butyl acrylate 150 parts by weight Newcol 707SF 62 parts by weight Ammonium persulfate 1 30 minutes after the completion of the dropping, 7.7 parts by weight of a solution of 0.7 parts by weight of ammonium persulfate dissolved in 7 parts by weight of deionized water was started to drop, and the dropping was completed over 30 minutes. . After keeping this at 80 ° C. for another 2 hours,
The temperature was lowered to 0 ° C. Then, the pH was adjusted to 8 to 9 with aqueous ammonia, and the copolymer emulsion (A) having a solid content of 51% by weight was prepared.
-1) was obtained. The pH of the emulsion was 8.2.

Production Example 2 A copolymer emulsion (A-2) having a solid content of 55% by weight was obtained in the same manner as in Production Example 1 except that the pre-emulsion to be dropped had the following composition. The pH of the emulsion is 8.4
Met. Deionized water 315 parts by weight Diacetone acrylamide 74 parts by weight Acrylic acid 3.6 parts by weight Styrene 105 parts by weight Methyl methacrylate 269 parts by weight 2-ethylhexyl acrylate 105 parts by weight n-butyl acrylate 176 parts by weight Hydroxyethyl acrylate 15 parts by weight Newcol 707SF 49 parts by weight Ammonium persulfate 1.5 parts by weight

Production of Aqueous Urethane Graft Resin (B) Production Example 3 Kyowanol D was placed in a two-liter four-necked flask.
(Texanol isobutyl ether manufactured by Kyowa Hakko) 8
60 parts by weight, polypropylene glycol (molecular weight of about 1,
000) 2,000 parts by weight, 740 parts by weight of polycaprolactone diol (molecular weight: about 530) and 210 parts by weight of 2,2'-dimethylolpropionic acid were charged at 100 ° C.
And 1,110 parts by weight of isophorone diisocyanate was added dropwise. After completion of the dropwise addition, the mixture was stirred at 100 ° C., and after 1 hour, when the concentration of the isocyanate group became 0.41 meq / g, 195 parts by weight of 2-hydroxyethyl methacrylate and 37 parts by weight of n-butyl alcohol were added, and the mixture was heated at 100 ° C.
After stirring for 4 hours, the mixture was cooled to 40 ° C., and triethylamine 16
2 parts by weight and 9,000 parts by weight of deionized water were added to obtain an aqueous dispersion of unsaturated polyurethane resin having a solid content of 30% by weight.
Next, 201 parts by weight of deionized water and 6 parts by weight of Newcol 707SF were added to a two-liter four-necked flask, and the temperature was maintained at 70 ° C. after nitrogen replacement. A pre-emulsion having the following composition and an aqueous catalyst solution were added dropwise thereto over 3 hours. Pre-emulsion Unsaturated polyurethane resin aqueous dispersion 333 parts by weight Deionized water 200 parts by weight Diacetone acrylamide 10 parts by weight Methyl methacrylate 100 parts by weight n-butyl acrylate 90 parts by weight Catalyst aqueous solution 1.5 parts by weight of t-butyl hydroperoxide Solution dissolved in 30 parts by weight of deionized water Solution prepared by dissolving 1.5 parts by weight of sodium formaldehyde sulfoxylate in 30 parts by weight of deionized water 30% by weight of a carbonyl group-containing aqueous urethane graft resin (B-1) was obtained. The pH of the emulsion was 8.3.

Production Example 4 Deionized water 333 was placed in a two-liter four-necked flask.
12 parts by weight of Newcol 707SF were added, and the mixture was maintained at 70 ° C. after nitrogen replacement. A pre-emulsion having the following composition was dropped therein over 3 hours. Aqueous dispersion of unsaturated polyurethane resin similar to Production Example 333 parts by weight Deionized water 600 parts by weight Diacetone acrylamide 20 parts by weight Styrene 100 parts by weight Methyl methacrylate 200 parts by weight n-butyl acrylate 80 parts by weight 2 parts by weight of ammonium persulfate Dropping After the completion, the temperature was further maintained at 70 ° C. for 1 hour, followed by cooling to obtain a carbonyl group-containing aqueous urethane graft resin (B-2) having a solid content of 30% by weight. The pH of the emulsion was 8.2.

Production Example 5 Deionized water 201 was placed in a two-liter four-necked flask.
6 parts by weight of Newcol 707SF were added, and the temperature was maintained at 70 ° C. after purging with nitrogen. A pre-emulsion having the following composition was dropped therein over 3 hours. Aqueous dispersion of unsaturated polyurethane resin similar to that of Production Example 3 333 parts by weight Deionized water 200 parts by weight Diacetone acrylamide 10 parts by weight Acrylic acid 4 parts by weight Styrene 36 parts by weight Methyl methacrylate 100 parts by weight n-butyl acrylate 50 parts by weight 2 parts by weight of ammonium sulfate After completion of the dropwise addition, the mixture was kept at 70 ° C. for 1 hour and then cooled to obtain a carbonyl group-containing aqueous urethane graft resin (B-3) having a solid content of 30% by weight. The pH of the emulsion was 8.4.

Production Example 6 To a two-liter four-necked flask, 333 parts by weight of the same aqueous dispersion of an unsaturated polyurethane resin as in Production Example 3 was added.
5 parts by weight of diacetone acrylamide, 25 parts by weight of methyl methacrylate, n-butyl acrylate 2
0 parts by weight and 87 parts by weight of deionized water were added, and after the temperature was raised to 70 ° C., a solution in which 0.75 parts by weight of t-butyl hydroperoxide was dissolved in 15 parts by weight of deionized water, and 0% by weight of sodium formaldehyde sulfoxylate were added. A solution prepared by dissolving 0.75 parts by weight in 15 parts by weight of deionized water was separately added dropwise for 3 hours, kept at 70 ° C. for 1 hour, cooled, and cooled to a solid content of 30% by weight of a carbonyl group-containing aqueous polyurethane resin (B). -4) was obtained. The pH of the emulsion was 8.3. 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. 960 parts by weight of tap water 240 parts by weight of ethylene glycol Nopcosperse 44C (pigment dispersant manufactured by San Nopco) 60 parts by weight SN deformer 364 (antifoaming agent manufactured by San Nopco) 84 parts by weight Fujichemi HEC KF-100 (thickening agent manufactured by Fuji Chemical) Agent) 36 parts by weight Titanium white 2640 parts by weight

Example 1 Emulsion (A) was placed in a stainless steel container having a capacity of 2 liters.
-1), 400 parts by weight of an aqueous urethane graft resin (B)
-1) to 667 parts by weight and adipic dihydrazide to 7.
0 parts by weight was added and stirred to obtain a resin mixture (D-1). Next, 201 parts by weight of the pigment paste prepared according to the following formulation is put into a stainless steel container having a capacity of 1 liter, and 475 parts by weight of the resin mixture (D-1) obtained above and 18 parts by weight of Texanol are added with stirring. The pH was adjusted to 7 to 9 with ammonium water to obtain a paint (E-1).

Examples 2 to 7 Resin mixed liquids (D-2) to (D-7) were prepared in the same manner as in Example 1 except that the emulsion, aqueous urethane graft resin, and adipic dihydrazide were used as shown in Table 1. Obtained.
Next, the pigment paste, the resin mixture, and Texanol are shown in Table 2.
Except that the paint (E-
2) to (E-7) were obtained.

Example 8 Emulsion (A) was placed in a stainless steel container having a capacity of 2 liters.
-1), 400 parts by weight of an aqueous urethane graft resin (B)
-1), 667 parts by weight, and 73 parts by weight of a semicarbazide compound solution (Note 1) are added, and the mixture is stirred and a resin mixture (D-8) is added.
I got Next, 201 parts by weight of the pigment paste prepared above were placed in a stainless steel container having a capacity of 1 liter, and 475 parts by weight of the resin mixture (D-8) and 18 parts by weight of texanol were added with stirring, and the pH was adjusted to 7 with ammonium water.
To 9 to obtain a paint (E-8). (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.

Comparative Examples 1 to 3 Resin mixed liquids (D-9) to (D-11) were prepared in the same manner as in Example 1 except that the emulsion, aqueous urethane graft resin, and adipic dihydrazide were blended as shown in Table 1. Obtained. Next, paints (E-9) to (E-11) were obtained in the same manner as in Example 1, except that the pigment paste, the resin mixture, and the texanol were changed to the proportions shown in Table 2. The properties of each paint are shown in Table 2.

[0037]

[Table 1]

[0038]

[Table 2]

Paint test A 70 × 150 × 0.8 mm bond board was coated with Esco (Kansai Paint Co., Ltd., epoxy / amine-based rust-preventive undercoat) and left for 24 hours to form a coated plate. Each of the paints obtained as described above was diluted with tap water at 0 to 8%, and applied by air spray at a coating amount of 120 g / m ² . After drying for 2 hours, apply the same paint by air spray for 1 hour.
Coating was performed at a coating amount of 20 g / m ² . Each of the obtained test plates was subjected to the following tests. The results are shown in Table 3.

(1) Water resistance test (A) After coating the above test plate, drying it for 2 hours at a temperature of 20 ° C. and a relative humidity of 75%, the test plate was half-submerged in 20 ° C. water. After one hour, the test plate was pulled up and the coated surface was visually evaluated. A: No change at all. ：: Partial blisters. Δ: All blisters. X: Paint eluted.

(2) Water resistance test (B) After the test plate was coated, dried at a temperature of 20 ° C. and a relative humidity of 75% for 7 days, the test plate was half-submerged in 20 ° C. water. After 5 days, the test plate was pulled up and the coated surface was visually evaluated. A: No change at all. ：: Partial blisters. Δ: All blisters. X: Paint eluted.

(3) Accelerated weathering test After coating the above test plate, drying it for 7 days at a temperature of 20 ° C. and a relative humidity of 75%, a weathering test was conducted for 1,500 hours using a sunshine weatherometer. And the gloss retention was calculated.

[0043]

(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.

(5) JIS A 6910 waterproofing standard-related test Elongation test After 24 hours, each paint was applied to a plate coated with Ares rubber tile rough (manufactured by Kansai Paint Co., Ltd., a thickening agent for exterior use) with a 2 mm blade. Each was coated with a brush so as to be 100 g / m ² . 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. In accordance with the JIS A 6910 hot / cold repetition test, the cycle of <immersion in water for 18 hours to 3 hours in a thermostat at −20 ° C. to heating in a thermostat at 50 ° C. for 5 hours> is defined as 15 cycles. The state of the coating film surface after the cycle test was visually evaluated. A: No abnormality in the coating film. ：: Swelling on part of the coating film. Δ: Swelling on the entire coating film. ×: Cracks are observed in the coating film.

(6) Coating workability Each paint was diluted with tap water, adjusted to a viscosity of 68 to 70 KU, and degreased on a 300 x 450 x 0.8 tin plate according to JIS.
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 ◎: No sagging is observed ○: Slight sagging is observed △: Clear sagging is observed, even from a distance of 5 m ×: Difference in film thickness between upper and lower parts of coated plate Extremely large 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

[0047]

[Table 3]

[0048]

According to the present invention, weather resistance and hardness due to acryl, low temperature due to urethane can be obtained by using a urethane graft resin component having a carbonyl group-containing copolymer as a trunk and polyurethane as a branch component in combination with an acrylic resin component. An excellent effect of forming a highly functional coating film with well-balanced properties such as physical properties is exhibited. Another advantage is that the amount of urethane used can be reduced.

────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code FI C09D 151/06 C09D 151/06 (72) Inventor Masami Sugishima 4-171-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Prefecture Kansai Paint Co., Ltd. (72) Inventor Nobuto Hirata 4-17-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Prefecture Kansai Paint Co., Ltd.

Claims (8)

[Claims] 1. An aqueous dispersion of a carbonyl group-containing copolymer (A) containing 2 to 50% by weight of an unsaturated polyurethane resin,
The carbonyl group-containing ethylenically unsaturated monomer is 0.01 to
40% by weight, and 10 to 9 other polymerizable unsaturated monomers.
A carbonyl group-containing aqueous urethane graft resin (B) obtained by copolymerization at a ratio of 7.99% by weight is
5 to 500 parts by weight per 100 parts by weight of the solid content of (A), and as a crosslinking agent, at least 2 parts per molecule
The hydrazine derivative (C) having two or more hydrazide groups or semicarbazide groups is prepared by converting the hydrazide group or semicarbazide group in the component (C) to 0 with respect to 1 mol of the carbonyl group contained in the components (A) and (B). A resin composition for a water-based paint formulated to be 0.12 to 2 mol. 2. The aqueous dispersion of a carbonyl group-containing copolymer (A) contains (a) 0.1 to 30% by weight of a polymerizable unsaturated monomer having at least one carbonyl group in one molecule, (B) 0 to 10% by weight of a water-soluble ethylenically unsaturated monomer copolymerizable with the monomer (a), and (c) 60 to 99.9% by weight of another ethylenically unsaturated monomer. The resin composition for an aqueous coating composition according to claim 1, which is a copolymer aqueous dispersion obtained by emulsion-polymerizing the contained monomer mixture in the presence of an emulsifier. 3. An unsaturated polyurethane resin comprising a diisocyanate compound (d) and a number average molecular weight of 62 to 10,000.
2. A resin obtained by reacting a polyol (e), a carboxyl group-containing diol (f) and a hydroxyl group-containing ethylenically unsaturated monomer (g).
Or the resin composition for water-based paints described in 2. 4. The method according to claim 1, wherein the unsaturated polyurethane resin is a polyurethane resin obtained by reacting isocyanate groups and hydroxyl groups at an equivalent ratio of 1: 1 to 1: 3. Water-based paint resin composition. 5. An unsaturated polyurethane resin comprising a hydroxyl group-containing ethylenically unsaturated monomer (g) as a hydroxy compound in an amount of 0.1 to 1 per equivalent of isocyanate group.
The aqueous paint resin composition according to any one of claims 1 to 4, wherein the resin composition is used in an equivalent ratio. 6. The unsaturated polyurethane resin has a solid content of 1 g.
The resin composition for an aqueous paint according to any one of claims 1 to 5, wherein the resin composition is a resin having an acid value of 10 to 200 per unit. 7. The aqueous carbonyl group-containing urethane graft resin (B) is obtained by using an unsaturated polyurethane resin as a polymer emulsifier, and using a carbonyl group-containing ethylenically unsaturated monomer (h) and another polymerizable unsaturated monomer. The resin composition for an aqueous paint according to any one of claims 1 to 6, which is a resin obtained by emulsion polymerization of the monomer (i). 8. The carbonyl group-containing aqueous urethane graft resin (B) comprises 2 to 50% by weight of an unsaturated polyurethane resin, 0.01 to 40% by weight of a carbonyl group-containing ethylenically unsaturated monomer (h), 0 to 10% by weight of a water-soluble ethylenically unsaturated monomer (j) and another polymerizable unsaturated monomer (i)
The resin composition for an aqueous paint according to any one of claims 1 to 7, wherein the resin is a resin obtained by copolymerizing the resin at a ratio of 0 to 99.99% by weight.