JPH10158575A - Normal temperature drying type aqueous coating material composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a normal temperature-drying type aqueous coating material composition capable of providing a coated film excellent in water resistance, adhesivity and weather resistance. SOLUTION: This composition comprises (A) an aldehyde group or keto group-containing carbonyl group-containing copolymer resin aqueous dispersion, (B) an alkoxysilyl group-containing copolymer resin aqueous dispersion, (C) a pigment, (D) an aldehyde group or keto group-containing carbonyl group- containing copolymer resin aqueous solution and (E) a hydrazine derivative containing at least two hydrazino groups in the molecule. The non-volatile content of the component B is 1-900wt.% of the amount of the component A, the amount of the component C is 1-60wt.% the whole non-volatile component, the amount of the non-volatile component of the component D is 0.1-10wt.% of the amount of the component C and the amount of the component E is an amount to make the molar ratio of the whole carbonyl group based on the aldehyde group and the keto group in the component A and the component D to hydrazino group in the component E of 0.2 to 5.0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold-drying aqueous coating composition, and more particularly, the present invention is suitable for interior and exterior coatings of buildings, and has excellent coating gloss, water resistance, adhesion, and the like. The present invention relates to a cold-drying aqueous coating composition capable of providing a weather-resistant coating film.

[0002]

2. Description of the Related Art Water-based paints are generally used in various fields because they have less solvent to be volatilized than solvent-based paints, so they are excellent in low pollution, safety and resource saving. ,
In addition, further expansion of applications is expected in the future. Nowadays,
In order to improve the water resistance, durability, and gloss of the water-based paint, there are also those using a water-dispersible resin having a reaction curing mechanism and a reactive water-soluble resin. On the other hand, the use of siloxane-introduced acrylic-modified copolymer emulsions for the purpose of improving the weather resistance, durability and adhesion of the coating has been studied in recent years, but it is not always satisfactory in terms of the durability of the coating. It doesn't work.

[0003]

DISCLOSURE OF THE INVENTION The present invention has improved the above-mentioned properties of water-based paints, that is, it can provide a coating film having excellent water resistance, gloss, adhesion and weather resistance and can be dried at room temperature. It is an object to provide an aqueous coating composition.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result, by mixing specific components in a specific ratio to obtain an aqueous coating composition. And reached the present invention.

More specifically, the cold-drying aqueous coating composition of the present invention comprises (A) 0.3 to 20% by weight of a carbonyl group-containing unsaturated monomer containing an ald group or a keto group, and an ethylenically unsaturated carboxylic acid. and the acid 0-10 wt%, C ₁ -C ₁₀ alkyl esters of acrylic acid or methacrylic acid, vinyl aromatic compounds, acrylonitrile, methacrylonitrile, a saturated carboxylic acid vinyl esters, vinyl halides, vinylidene halides, butadiene and ethylene 55 to 9 at least one unsaturated monomer selected from the group consisting of
Aqueous dispersion of a carbonyl group-containing copolymer resin obtained by emulsion polymerization of a monomer mixture of 9.7% by weight and 0 to 15% by weight of an unsaturated monomer other than the above unsaturated monomers (B) an alkoxysilyl group-containing copolymer resin aqueous dispersion, (C) a pigment, (D) (A) 1 to 30% by weight of a carbonyl group-containing unsaturated monomer containing an ald group or a keto group, (B) 10 to 65% by weight of an ethylenically unsaturated carboxylic acid, and (c) a C ₁ -C ₁₀ alkyl ester of acrylic acid or methacrylic acid;
5-89% by weight of at least one unsaturated monomer selected from the group consisting of vinyl aromatic compounds, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl propionate, vinyl halide, vinylidene halide, butadiene and ethylene And (d) a carbonyl group-containing copolymer obtained by solution polymerization or emulsion polymerization of a monomer mixture of 0 to 50% by weight of an unsaturated monomer other than the monomers (a) to (c). (E) at least two hydrazino groups (—NH in the molecule)
NH ₂ ), the component (B) has a nonvolatile content of 1 to 900% by weight based on the nonvolatile content of the component (A), and the component (C) has a total amount of 1 to 60% by weight based on the nonvolatile content, and the nonvolatile content of component (D) is 0.1 to
10% by weight, and the amount of the component (E) is 0.1% in a molar ratio of the total carbonyl groups based on the ald or keto groups in the components (A) and (D) to the hydrazino groups in the component (E). The amount is 2 to 5.0.

[0006] In the present specification, "a carbonyl group-containing copolymer resin containing an ald group or a keto group" refers to a resin containing an ald group or a keto group and therefore containing a carbonyl group based on the ald group or the keto group. Similarly, a carbonyl group-containing unsaturated monomer containing an ald group or a keto group means an ald group or a keto group, and thus contains an ald group or a keto group. Based on unsaturated monomers containing a carbonyl group.

[0007]

DETAILED DESCRIPTION OF THE INVENTION As described above, the aqueous dispersion of a carbonyl group-containing copolymer resin as the component (A) in the coating composition of the present invention contains a carbonyl group-containing unsaturated group containing an ald group or a keto group. 0.3 to 20% by weight of a monomer;
An ethylenically 0-10 wt% unsaturated carboxylic acid, C ₁ -C ₁₀ alkyl esters, vinyl aromatic compounds of acrylic acid or methacrylic acid, acrylonitrile, methacrylonitrile, a saturated carboxylic acid vinyl esters, vinyl halides, halogenated 55 to 99.7% by weight of at least one unsaturated monomer selected from the group consisting of vinylidene, butadiene and ethylene, and 0 to 15% by weight of an unsaturated monomer other than the above-mentioned unsaturated monomers Is an aqueous dispersion of a copolymer resin obtained by emulsion polymerization of a monomer mixture of This type of copolymer resin aqueous dispersion is disclosed, for example, in JP-B-58-20991 and JP-B-61-6861.
JP-A-57-3850 and JP-A-58-9664.
No. 3 is publicly known.

Examples of the carbonyl group-containing unsaturated monomer containing an ald group or keto group of the above-mentioned monomers include acrolein, diacetone acrylamide, formyl styrene and vinyl alkyl ketone having 4 to 7 carbon atoms. (For example, vinyl methyl ketone, vinyl ethyl ketone, vinyl butyl ketone, etc.), a general formula

[0009]

Embedded image Wherein R ¹ is a H atom or a CH ₃ group, R ² is a H atom or a C ₁ -C ₃ alkyl group, and R ³ is a C ₁ -C ₃
An alkyl group, and R ⁴ is a C ₁ -C ₄ alkyl group. ) (Acrylic (or methacrylic) oxyalkyl propenal, diacetone acrylate, acetonyl acrylate, diacetone methacrylate, 2-
Hydroxypropyl acrylate acetyl acetate,
Butanediol-1,4-acrylate acetyl acetate and the like can be mentioned. Diacetone acrylamide, acrolein and vinyl methyl ketone are particularly preferred. These monomers may be used in combination of two or more.

The amount of the monomer is 0.3 to 20% by weight, preferably 1 to 20% by weight of the total amount of the monomers to be copolymerized.
15% by weight. If the amount of the monomer is too small,
The content of the ald group or keto group in the resulting copolymer resin is reduced, and as a result, the density of the crosslinked structure caused by the reaction with the hydrazine derivative of the component (E) is reduced, and the coating film of the aqueous coating composition is formed. The water resistance decreases. Also, if the amount of the monomer is too large, the relative content of the other monomer is reduced, and as a result, the effect brought by the other monomer is reduced. Not preferred.

In preparing the aqueous dispersion of the carbonyl group-containing copolymer resin of the component (A), the monomeric ethylenically unsaturated carboxylic acid is an optional component and may or may not be blended. When blended, the monomer may be a monocarboxylic acid or a polycarboxylic acid,
Preferred are monoolefinically unsaturated carboxylic acids having 3 to 5 carbon atoms. Particularly, acrylic acid, methacrylic acid and itaconic acid are preferred. The amount of monomer
0 to 10% by weight of the total amount of the monomers to be copolymerized. The incorporation of a monomer improves the pigment dispersibility and storage stability of the aqueous coating composition, and improves the water resistance of the coating film of the aqueous coating composition. However, if the amount of the monomer is too large, the relative content of the other monomer is reduced, and as a result, the effect brought by the other monomer is reduced. Not preferred.

The unsaturated monomers of the above-mentioned monomers include:
The aforementioned C ₁ -C ₁₀ alkyl esters of acrylic acid or methacrylic acid (eg, methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, ethyl methacrylate), vinyl aromatic compounds (eg, styrene),
Acrylonitrile, methacrylonitrile, saturated vinyl carboxylate (eg, vinyl acetate, vinyl propionate), vinyl halide, vinylidene halide,
At least one unsaturated monomer selected from the group consisting of butadiene and ethylene is used.

The amount of the monomer is 55 to 99.7% by weight, preferably 6 to 9, of the total amount of the monomers to be copolymerized.
0 to 99% by weight. If the amount of the monomer is too small, the water resistance of the coating film of the water-based coating composition decreases. The reason for this is not clear, but it is presumed that the resulting copolymer resin may have poor affinity for the resin or pigment of the aqueous copolymer resin dispersion of component (D). . Also, if the compounding amount of the monomer is too large, the relative content of the other monomer is reduced, and as a result, the effect provided by the other monomer, for example, of the aqueous coating composition It is not preferable because the water resistance of the solidified coating film is reduced.

In the preparation of the aqueous dispersion of the carbonyl group-containing copolymer resin of the component (A), monomers other than the above-mentioned monomers (1) to (4) can be blended if desired. Specific examples of the monomer include, for example, monoolefinically unsaturated carboxylic acid amides (eg, acrylamide, methacrylamide, itaconic acid amide, etc.) and N-alkyl and / or N-
Alkylol derivatives (eg, N-methylacrylamide, N-isobutylacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-
Butoxymethylacrylamide), monoolefinically unsaturated sulfonic acids (eg, vinylsulfonic acid, methylacrylamidepropanesulfonic acid, etc.).
These monomers can be copolymerized by using two or more kinds in combination. The amount of the monomer is from 0 to 15% by weight based on the total amount of the monomers to be copolymerized. It is not preferable that the content of the monomer is too large because the relative content of the other monomer is reduced, and as a result, the effect brought by the other monomer is reduced. .

In order to obtain an aqueous dispersion of the carbonyl group-containing copolymer resin of the component (A) used in the present invention, the above-mentioned unsaturated monomer mixture is polymerized by emulsion polymerization. For the emulsion polymerization, a method of performing polymerization with a water-soluble polymerization initiator using an emulsifier, a method of performing polymerization by soap-free polymerization, and the like are used. Examples of the emulsifier include various anionic, cationic, and nonionic emulsifiers, and further, a polymer emulsifier. Particularly preferred emulsifiers are carbonyl group-containing polymer emulsifiers described in JP-A-64-48801. As the polymerization initiator used in the emulsion polymerization, inorganic peroxides such as potassium persulfate, ammonium persulfate, and hydrogen peroxide are preferable. These inorganic peroxides may be used as a redox initiator in combination with a reducing agent such as Rongalit, L-ascorbic acid, or an organic amine.

Various methods can be used for supplying the monomer in the emulsion polymerization. For example, various methods such as a batch charging method, a monomer addition method, and an emulsion addition method can be used. Also, a seed polymerization method in which the composition of the monomer to be added is sequentially changed, a power sulfide polymerization method, or the like can be used. In the case of emulsion polymerization, a chain transfer agent can be used to adjust the molecular weight in order to obtain desired physical properties of the coating film. Examples of the chain transfer agent include various mercaptans, α-methylstyrene, alkyl halides, alcohols and the like. The compounding amount is preferably 0.03 to 5% by weight based on all monomers.

The aqueous dispersion of the alkoxysilyl group-containing copolymer resin as the component (B) in the coating composition of the present invention is specifically produced as follows. That is, an acid group-containing copolymer obtained by solution polymerization of an alkoxysilyl group-containing vinyl monomer with an unsaturated monomer having an acid group, for example, (meth) acrylic acid, an alkyl ester of (meth) acrylic acid, or (meth) acrylamide. It is obtained by neutralizing a polymer with an amino compound and dispersing it in water. It can also be produced by emulsion polymerization using an emulsifier.

Examples of the vinyl monomer having an alkoxysilyl group include vinyl silanes such as vinyl methyl dimethoxy silane, vinyl trimethoxy silane, vinyl triethoxy silane and vinyl tri (β-methoxy ethoxy) silane; γ-methacryloxypropyl trimethoxy silane;
γ-methacryloxypropylmethyldimethoxysilane,
(meth) acryloxyalkylsilanes such as γ-acryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-acryloxypropyltriethoxysilane; polyurethane having at least one vinyl group and alkoxysilyl group Examples thereof include polymerizable oligomers having an alkoxysilyl group, such as oligomers, polyether oligomers, polyamide oligomers, epoxy oligomers, and polyester oligomers.

The pigment as the component (C) in the coating composition of the present invention may be either an organic pigment or an inorganic pigment, or both pigments may be used in combination. In addition, any of the extender and the coloring pigment can be used,
Further, both can be used in combination. Specific examples of the pigment include inorganic extenders such as calcium carbonate, clay, talc, mica powder, barite, finely divided silica, diatomaceous earth, calcium silicate, aluminum silicate, barium carbonate, and magnesium carbonate; titanium oxide, Zinc oxide, lithopone, carbon black, black iron oxide, loess,
Inorganic coloring pigments such as yellow iron oxide, titanium yellow, red iron oxide, iron oxide powder, ultramarine blue, and chromium oxide; and organic coloring pigments such as Hansa Yellow, Permanent Yellow, Permanent Red, Phthalocyanine Blue, and Phthalocyanine Green.

These pigments can be added directly to the aqueous resin dispersion of the component (A). However, as a dispersant, a carbonyl group-containing copolymer containing an ald group or a keto group of the component (D) described below is used. It is common to add a pigment paste after using a combined resin aqueous liquid, or to add a pigment paste using another pigment dispersant, a thickener, or the like.

As described above, the aqueous dispersion of a carbonyl group-containing copolymer resin, which is the component (D) in the coating composition of the present invention, comprises (a) a carbonyl group-containing unsaturated monomer containing an ald group or a keto group. 1 to 30% by weight of a monomer, (b) 10 to 65% by weight of an ethylenically unsaturated carboxylic acid, and (C)
C ₁ -C ₁₀ alkyl esters of acrylic acid or methacrylic acid, vinyl aromatic compounds, acrylonitrile, selected methacrylonitrile, vinyl acetate, vinyl propionate, vinyl halides, vinylidene halides, from the group consisting of butadiene and ethylene 5 to 89% by weight of at least one unsaturated monomer, and (d) the above (a) to (c)
Is an aqueous solution of a carbonyl group-containing copolymer resin obtained by solution polymerization of a monomer mixture with 0 to 50% by weight of an unsaturated monomer other than the above monomers.

As the carbonyl group-containing unsaturated monomer containing an aldo group or a keto group of the monomer (a), the preparation of an aqueous dispersion of the carbonyl group-containing copolymer resin of the component (A) The same monomers as those exemplified for the monomer used in the above are used. The amount of the monomer (a) is 1% of the total amount of the monomers (a) to (d) to be copolymerized.
-30% by weight, preferably 3-15% by weight. If the amount of the monomer (a) is too small, the content of the ald group or the keto group in the resulting copolymer resin becomes small, and as a result, the cross-linking caused by the reaction with the hydrazine derivative of the component (E) occurs. The density of the structure decreases, and the water resistance of the coating film of the aqueous coating composition decreases. On the other hand, if the amount of the monomer (a) is too large, the content of the monomer (b) in the resulting copolymer resin becomes relatively small, and the solubility is insufficient even by adding an alkali. In addition, the affinity with the pigment is reduced, and the dispersibility of the pigment is deteriorated.

Examples of the ethylenically unsaturated carboxylic acid of the monomer (b) include those exemplified for the monomer used for preparing the carbonyl group-containing copolymer resin aqueous dispersion of the component (A). The same monomer as the monomer is used. The amount of the monomer (b) is 10 to 65% by weight, preferably 20 to 50% by weight, based on the total amount of the monomers (A) to (D) to be copolymerized. If the amount of the monomer (b) is too small, the pigment dispersibility and the storage stability of the aqueous coating composition deteriorate. Further, when the amount of the monomer (b) is too large, the amount of the monomer (a) is relatively small, and the water resistance of the coating film of the water-based coating composition is reduced. Affinity also worsens.

As the unsaturated monomer of the above-mentioned monomer (c), the monomer exemplified for the monomer used for preparing the aqueous dispersion of the carbonyl group-containing copolymer resin of the above-mentioned component (A) may be used. The same monomers as in the body are used. Monomer (c)
Is from 5 to 89% by weight, preferably from 30 to 70% by weight, based on the total amount of the monomers (a) to (d) to be copolymerized. If the amount of the monomer (c) is too small, the water resistance of the coating film of the water-based coating composition decreases. The reason for this is not always clear, but it is presumed that it is probably because the resulting copolymer resin has poor affinity for the resin or pigment of the aqueous copolymer resin dispersion of the component (A). . On the other hand, if the amount of the monomer (c) is too large, the content of the monomer (a) or the monomer (b) in the produced copolymer resin decreases, so that the solidification of the aqueous coating composition The water resistance of the coating film decreases,
The dispersibility of the pigment may deteriorate.

In the preparation of the aqueous dispersion of the carbonyl group-containing copolymer resin of the component (D), a monomer (d) other than the above-mentioned monomers (a) to (c) may be added, if desired. it can. Examples of the unsaturated monomer of the monomer (d) include the same monomers as those exemplified for the monomer used for preparing the aqueous dispersion of the carbonyl group-containing copolymer resin of the component (A). Mers are used. The amount of the monomer (d) is 0 to the total amount of the monomers (a) to (d) to be copolymerized.
It is in the range of 50% by weight. If the amount of the monomer (d) is too large, the relative content of the other monomer is reduced, and as a result, the effect brought by the other monomer is reduced. Is not preferred.

The unsaturated monomer mixture of the above (a) to (d) for obtaining an aqueous solution of a carbonyl group-containing copolymer resin containing an ald group or keto group of the component (D) used in the present invention. Is carried out by solution polymerization or emulsion polymerization.
The solvent used for the solution polymerization is not particularly limited, but a water-soluble or hydrophilic solvent is preferable from the viewpoint of solubility of the produced copolymer resin and miscibility with water. Specific examples thereof include monoalcohols having 1 to 4 carbon atoms such as methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol and t-butyl alcohol; ethylene glycol and derivatives thereof such as ethylene Glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether; diethylene glycol and its derivatives such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether;
And dioxane. Further, water may be used as the polymerization solvent. One of these solvents may be used, or two or more of them may be appropriately used in combination. In general, a solvent having a boiling point of 200 ° C. or less is preferable in terms of distillation after polymerization or drying speed.

Specific examples of the polymerization initiator for solution polymerization include azo initiators such as azobisisobutyronitrile and azobisvaleronitrile; benzoyl peroxide;
Organic peroxide-based initiators such as lauroyl peroxide and t-butyl peroxide; azo-based compounds; and inorganic peroxide-based initiators such as hydrogen peroxide and ammonium persulfate can be used. One of these initiators may be used alone alone as appropriate depending on the solubility in a solvent or the like.
More than one species can be used as appropriate. Further, a reducing agent such as Rongalit, L-ascorbic acid, or an organic amine may be used in combination with these initiators to be used as a redox initiator.

For the emulsion polymerization, a method of using an emulsifier to carry out polymerization with a water-soluble polymerization initiator, a method of carrying out polymerization by soap-free polymerization, and the like are used. Examples of the emulsifier include various anionic, cationic, and nonionic emulsifiers, and further, a polymer emulsifier. Particularly preferred emulsifiers are described in JP-A-64-488.
It is a carbonyl group-containing polymer emulsifier described in JP-A-01. As the polymerization initiator used in the emulsion polymerization, inorganic peroxides such as potassium persulfate, ammonium persulfate, and hydrogen peroxide are preferable. These inorganic peroxides may be used as a redox initiator in combination with a reducing agent as described above.

Various methods can be used for supplying the monomer in the emulsion polymerization. For example, various methods such as a batch charging method, a monomer addition method, and an emulsion addition method can be used. Also, a seed polymerization method in which the composition of the monomer to be added is sequentially changed, a power sulfide polymerization method, or the like can be used. In the case of emulsion polymerization, a chain transfer agent can be used to adjust the molecular weight in order to obtain desired physical properties of the coating film. Examples of the chain transfer agent include various mercaptans, α-methylstyrene, alkyl halides, alcohols and the like. The compounding amount is preferably 0.03 to 5% by weight based on all monomers.

The hydrazine derivative having at least two hydrazino groups in the molecule of the component (E) used in the present invention is, for example, a dicarboxylic acid having 2 to 10, especially 4 to 6 carbon atoms. Dihydrazide (for example, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, maleic acid dihydrazide, fumaric acid dihydrazide, itaconic acid dihydrazide), and carbon atoms having 2 to 4 fatty acids. Water-soluble dihydrazine (for example, ethylene-1,2-dihydrazine, propylene-1,3-dihydrazine, butylene-1,4-dihydrazine, etc.) can be mentioned.

The general formula

Embedded image (Wherein X is a hydrogen atom or a carboxyl group, Y is a hydrogen atom or a methyl group, A is each unit of acrylamide, methacrylamide, acrylate, methacrylate or maleic anhydride, and B is A is a unit of a monomer copolymerizable with A, and k, m and n are the following formulas: 2 mol% ≦ k ≦ 100 mol% 0 mol% ≦ (m + n) ≦ 98 mol% (k + m + n) = A polymer satisfying 100 mol%) can also be used as the hydrazine derivative. Such polymers are described in detail, for example, in JP-A-55-6535.

The aqueous coating composition of the present invention contains the components (A) to (E) described in detail above, but there is a desirable range for the mixing ratio of each component. The nonvolatile content of the component (B) is 1 to 900% by weight based on the nonvolatile content of the component (A). If the amount of the component (B) is too small, sufficient effects cannot be obtained in terms of weather resistance and adhesion.
On the other hand, if the amount of the component (B) is too large, the durability of the coating film is inferior, and it is not suitable as a water-based paint.

The compounding amount of the component (C) (pigment) is 1 to 10 in terms of the pigment concentration (PWC) based on the total non-volatile content of the aqueous coating composition.
60% by weight. If the PWC is too low, the gloss of the coating film is excellent, but the opacity is insufficient. On the other hand, if the PWC is too high, the glossiness of the coating film decreases, and the coating film becomes unsuitable as a water-based paint.

The component (D) acts as a pigment dispersant, and at the same time, after the coating film of the aqueous coating composition is dried, it reacts with the component (E) to form a cross-linking bond, thereby increasing the water resistance of the coating film. It works to improve. Therefore, the component (D) is different from the ordinary pigment dispersant. Even when a large amount of the component (D) is added, the water resistance of the dried coating film is hardly reduced. Addition amount (usually 0.1 to 2
% By weight). When a relatively large amount of the component (D) is added, the component (D) can not only act as a pigment dispersant but also act as a binder, and can also provide glossiness, particularly sharpness. Excellent coating film is obtained.

The proportion of the non-volatile component used in the component (D) is 0.1 to 10% by weight, preferably 0.5 to 8% by weight, based on the amount of the component (C). If the use ratio is too small, a sufficient pigment dispersing effect cannot be obtained, and the glossiness of the coating film,
The sharpness and the storage stability of the paint decrease. On the other hand, if the amount is too large, not only the effect corresponding thereto cannot be improved, but also the water resistance decreases.

The compounding amount of the component (E) is the molar ratio of the total carbonyl group based on the ald group or keto group contained in the component (A) and the component (D) to the hydrazino group in the hydrazine derivative, that is, (> C ＯO) / (— NHNH ₂ ) in a molar ratio of preferably 0.2 to 5.0, more preferably 0.3 to 2.0. If the amount of the component (E) is too small, the degree of cross-linking of each of the components (A) and (D) with each other becomes insufficient, and the water resistance of the coating film decreases. Further, if the amount of the component (E) is too large, not only the improvement in water resistance corresponding to the amount is not obtained, but also the coating film becomes brittle.

The addition of the component (E) may be carried out at any time as long as it is other than the polymerization step of the component (A) and the polymerization step of the component (D) in the aqueous paint production process. ) Or the component (D) in which the carboxyl group is neutralized is preferred from the viewpoint of the storage stability of the aqueous coating composition.

The cold-drying aqueous coating composition of the present invention may contain, in addition to the above-mentioned components (A) to (E), various additives which may be added to this type of aqueous coating, for example, a thickening agent. Agents, defoamers, plasticizers, film-forming auxiliaries, and the like can be appropriately compounded. The cold-drying aqueous coating composition of the present invention has excellent water resistance, gloss, adhesion, and weather resistance of the coating film, and thus is suitable as a topcoat coating and / or an undercoat for inorganic materials.

[0039]

The present invention will be described in detail below with reference to production examples, examples and comparative examples of the components (A) and (D). In these examples, "parts" means parts by weight and "%" means% by weight.

Preparation Example 1 of Component (A) A temperature controller, a light stirrer, a reflux condenser, a supply vessel,
An emulsifier aqueous solution consisting of a mixture having the following composition was charged into a reaction vessel equipped with a thermometer and a nitrogen inlet tube. Water 200 parts 35% aqueous solution of sulfuric acid half-ester salt of 20 mol ethylene oxide added p-nonylphenol (hereinafter referred to as "anionic emulsifier aqueous solution") 5 parts 20% aqueous solution of 25 mol ethylene oxide added p-nonyl phenol 20 parts

Separately, a mixture having the following composition was prepared as the feed I and the feed II. Feed I: 200 parts of water 25 parts of the above-mentioned anionic emulsifier aqueous solution 25 parts Acrylic acid 5 parts Diacetone acrylamide 14 parts Butyl acrylate 205 parts Styrene 242 parts Feed II: 2.5 parts of potassium persulfate dissolved in 85 parts of water Aqueous solution

After replacing the inside of the reaction vessel charged with the aqueous solution of the emulsifier with nitrogen gas, 10% of the above-mentioned feed I was added, and the mixture was heated to 90 ° C. Then feed II
Of the remaining feed I while maintaining the same temperature.
And Feed II was gradually and uniformly fed over 3 to 3.5 hours to carry out polymerization. After completion of the supply, the emulsion polymerization was maintained at 90 ° C. for 1.5 hours to complete the emulsion polymerization. After completion of the emulsion polymerization, 28% aqueous ammonia was added to adjust the pH to 8
To obtain a copolymer resin aqueous dispersion. The nonvolatile content of this copolymer resin aqueous dispersion was 48%. Also,
The film forming temperature of this copolymer resin was 25 ° C. This copolymer resin aqueous dispersion is referred to as copolymer resin dispersion A-1 in Table 1 below.

Preparation Example 2 of Component (A) Instead of Feed I used in Preparation Example 1 of Component (A), 200 parts of water 25 parts of the above anionic emulsifier aqueous solution 25 parts of acrylic acid 7 parts of diacetone acrylamide 40 parts of acrylic A copolymer resin aqueous dispersion was prepared in the same manner as in Preparation Example 1 of Component (A), except that a mixture comprising 190 parts of butyl acid and 229 parts of styrene was used. The nonvolatile content of this copolymer resin aqueous dispersion was 48%. The film forming temperature of this copolymer resin was 25 ° C. This copolymer resin aqueous dispersion is referred to as copolymer resin dispersion A-2 in Table 1 below.

Synthesis Example 1 of Component (D) A temperature controller, an irrigating stirrer, a reflux condenser, a supply vessel,
100 parts of isopropanol was charged into a reaction vessel equipped with a thermometer and a nitrogen inlet tube. Separately, a mixture having the following composition was prepared. Isopropanol 100 parts Methyl acrylate 45 parts Butyl acrylate 10 parts Acrylic acid 35 parts Diacetone acrylamide 10 parts Azobisisobutyronitrile 4 parts

After the inside of the reaction vessel charged with 100 parts of the above isopropanol was replaced with nitrogen gas, the temperature was raised to 80 ° C., and the above mixture was gradually added over 2 hours while maintaining the same temperature for 2 hours. The reaction was maintained. After the completion of the reaction, 198 parts of a 10% aqueous solution of sodium hydroxide and 350 parts of water were added to the reaction product, and the temperature was set to 20 mmHg at a water bath temperature of 80 ° C.
By heating under reduced pressure, 500 parts of a mixture of isopropanol and water was distilled off to obtain 350 parts of an aqueous solution of a carbonyl group-containing copolymer resin. This aqueous resin solution has a pH of 8.
5. A clear solution having a nonvolatile content of 32%. This aqueous carbonyl group-containing copolymer resin solution is referred to as a copolymer resin aqueous solution D-1 in Table 1 below.

Synthesis Example 2 of Component (D) As a mixture supplied to a reaction vessel, 100 parts of isopropanol 13 parts of methyl methacrylate 13 parts of styrene 25 parts of methacrylic acid 40 parts of diacetone acrylamide 17 parts of azobisisobutyronitrile 4 parts The reaction was carried out in the same manner as in Synthesis Example 1 of Component (D), except that a mixture of the following was used, and the same post treatment was carried out to obtain an aqueous solution of a carbonyl group-containing copolymer resin. This aqueous resin solution was a transparent solution having a nonvolatile content of 32%. This aqueous carbonyl group-containing copolymer resin solution is referred to as “Copolymer resin aqueous solution D-2” in Table 1 below.

Examples 1 to 8 and Comparative Examples 1 to 3 0, 2, or 5 parts of the aqueous solution of the carbonyl group-containing copolymer resin obtained in Synthesis Example 1 or 2 of Component (D) , For the comparative example), 15 parts of water, 2 parts
0.2 parts of 8% aqueous ammonia, 2 parts of a 20% aqueous solution of sodium polyacrylate, 1 part of an antifoaming agent (trade name: SN Deformer 315 manufactured by San Nopco Co., Ltd.) and 20 parts of titanium oxide or 3 parts of carbon black as a pigment (each Example,
The amounts shown in Table 1 for Comparative Examples) were mixed with a disper to prepare a pigment paste.

To the pigment paste thus obtained, 0 parts of the aqueous resin dispersion obtained in Preparation Example 1 or 2 of Component (A), 10 parts
Parts, 30 parts, 50 parts, 55 parts, or 60 parts (the amounts shown in Table 1 for each example and comparative example), an aqueous acrylic silicone resin containing an alkoxysilyl group-containing copolymer resin (Chuo Rika Kogyo Co., Ltd.) Company-made product name Ricabond E
S-J547, NV = 52%, MFT = 5 ° C.) 0 parts, 5 parts
Parts, 10 parts, 30 parts, 50 parts or 60 parts (the amount shown in Table 1 for each of Examples and Comparative Examples), 1.2 parts of adipic dihydrazide and 4 parts of ethyl cellosolve were mixed together to obtain an aqueous coating composition. did. With respect to these water-based coating compositions, the following tests were carried out on the coating film gloss, initial adhesion, coating water resistance and coating weather resistance.

(A) Gloss of Coating Film The coating composition was applied to a glass plate so as to have a wet thickness of 150 μm and dried at 20 ° C. and 65% RH for 48 hours. It was measured. (B) Initial adhesion The coating composition was applied twice to a flexible board (150 x 70 mm) with a brush, dried at 20 ° C and 65% RH for 7 days, and then applied to the coating at an angle of 60 ° with an NT cutter. Make a wound,
The gum tape was stuck and the gum tape was quickly peeled off, and the state of the coated surface was visually evaluated according to the following criteria.・ ・ ・: No peeling was observed at all. Δ: Peeling of the coating film of less than 25% is observed. ×: Peeling of the coating film of 25% or more is observed.

(C) Coating Water Resistance The coating composition was applied twice to a flexible plate (150 × 70 mm) with a brush and dried at 20 ° C. and 65% RH for 7 days to obtain test pieces. After the test piece was immersed in water for 7 days, the state of blistering of the coating film was visually examined and evaluated according to the following criteria.・ ・ ・: No blister was observed at all. ×: Blister generation was observed.

(D) Weather resistance of coating film A test piece prepared in the same manner as in the above-described water resistance test for a coating film was attached to a 30 ° outdoor exposure test stand on the south side, exposed for one year, washed with water, The coated surface was visually evaluated according to the following criteria.・ ・ ・: Slight stain, no decrease in gloss. Δ: Stain or decrease in gloss is observed. ×: Significant decrease in stain or gloss. The physical property test results of these aqueous coating compositions were as shown in Table 1.

[0052]

[Table 1]

As is evident from the data in Table 1, the water-based paint compositions of the respective examples were compared with the water-based paint compositions of Comparative Examples 1 to 3, and showed that the gloss of the coating film, the initial adhesion, the water resistance of the coating film and Excellent weather resistance in good balance.

[0054]

The cold-drying aqueous coating composition of the present invention comprises:
An excellent coating film having a good balance of coating film gloss, initial adhesion, coating water resistance and coating weather resistance can be obtained.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 131/02 C09D 131/02 133/06 133/06 133/20 133/20 147/00 147/00

Claims (1)

[Claims] (A) 0.3 to 20% by weight of a carbonyl group-containing unsaturated monomer containing an ald group or a keto group;
An ethylenically 0-10 wt% unsaturated carboxylic acid, C ₁ -C ₁₀ alkyl esters, vinyl aromatic compounds of acrylic acid or methacrylic acid, acrylonitrile, methacrylonitrile, a saturated carboxylic acid vinyl esters, vinyl halides, halogenated 55 to 99.7% by weight of at least one unsaturated monomer selected from the group consisting of vinylidene, butadiene and ethylene, and 0 to 15% by weight of an unsaturated monomer other than the above-mentioned unsaturated monomers (B) an aqueous dispersion of a carbonyl group-containing copolymer resin obtained by emulsion polymerization of a monomer mixture with (B) an alkoxysilyl group-containing copolymer resin, (C) a pigment, (D) (a) 1 to 30% by weight of a carbonyl group-containing unsaturated monomer containing an ald group or a keto group, (b) 10 to 65% by weight of an ethylenically unsaturated carboxylic acid, C ₁ -C ₁₀ alkyl esters of acrylic acid or methacrylic acid,
5-89% by weight of at least one unsaturated monomer selected from the group consisting of vinyl aromatic compounds, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl propionate, vinyl halide, vinylidene halide, butadiene and ethylene And (d) a carbonyl group-containing copolymer obtained by solution polymerization or emulsion polymerization of a monomer mixture of 0 to 50% by weight of an unsaturated monomer other than the monomers (a) to (c). (E) at least two hydrazino groups (—NH in the molecule)
NH ₂ ), wherein the non-volatile content of component (B) is 1 to 900% by weight based on the non-volatile content of component (A), and the total amount of component (C) is 1 to 60% by weight based on the nonvolatile content, and 0.1 to 10% by weight of the component (D) based on the content of the component (C).
Wherein the amount of the component (E) is 0.2 to 5 in terms of the molar ratio of all carbonyl groups based on ald groups or keto groups in the components (A) and (D) to the hydrazino groups in the component (E). .
A cold-drying aqueous coating composition, wherein the amount is 0.