JPH07118570A - Water-based coating primer - Google Patents

Abstract

PURPOSE:To provide the title primer especially excellent in adhesion and also in durability to a change in the environmental conditions, and satisfactory in water, chemical and weather resistances, etc. CONSTITUTION:The primer comprises 100 pts.wt. (in terms of the solid matter) aqueous emulsion of fine particles having a mean-particle diameter of 0.003-0.1mum and made from a polymer of 10-100wt.% acrylic ester monomer and/or methacrylic ester monomer and 90-0wt.% other monomers, 0-5 pts.wt. fluorine-containing surfactant, and 0-100 pts.wt. inorganic pigment.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an aqueous coating primer containing an aqueous polymer fine particle emulsion.

[0002]

2. Description of the Related Art Cement concrete, cement mortar, slate, glass and other industrial materials, wood materials such as civil engineering structural materials, general buildings, automobiles, electric appliances and furniture, wood materials such as plywood, and metals. When coating various structural materials such as plastic materials and plastic materials, a method of applying a primer to the structural material in advance and drying it before applying a top coat paint in order to enhance the adhesion between the structural material and the paint ing. As such a primer, urethane resin,
Solvent-based primers that use acrylic resin, silicone resin, etc. and water-based primers that use acrylic resin emulsion, vinyl acetate resin emulsion, etc. are known, but from the viewpoint of pollution prevention, fire safety, etc. Since then, the transition to water-based methods that do not use organic solvents is progressing rapidly. However, conventional water-based primers generally have poor penetrability into structural materials, have insufficient adhesion with structural materials, and also have problems such as insufficient adhesion with topcoat paints. Even if these materials are completely different for both the structural material and the top coating,
There is a strong demand for the development of aqueous primers that exhibit high adhesion.

[0003]

The present invention is based on the background of the above-mentioned conventional technical problems, and in particular, the relationship between the particle size and the polymer composition of the polymer emulsion constituting the aqueous primer for coating and the permeability to the structural material. It was discovered as a result of intensive research on the above.It has particularly excellent adhesion compared to conventional water-based primers containing acrylic resin, and also has excellent durability against changes in environmental conditions such as temperature and atmosphere, and water resistance. Another object of the present invention is to provide a water-based primer for coating which has good chemical resistance and weather resistance.

[0004]

The present invention relates to (A) 10 to 100% by weight of an acrylic acid ester monomer and / or a methacrylic acid ester monomer and 90 to 0% by weight of another monomer. Average particle size of 0.003 to 0.1μ
100 parts by weight (in terms of solid content) of polymer fine particle aqueous emulsion of m, (B) 0 to 5 parts by weight of a fluorosurfactant, and (C) 0 to 100 parts by weight of an inorganic pigment for coating. The main point is an aqueous primer.

The present invention will be described in detail below. This will clarify the objects, configurations and effects of the present invention. The polymer fine particle aqueous emulsion that constitutes the aqueous primer for coating of the present invention is an acrylic acid ester monomer and / or a methacrylic acid ester monomer (hereinafter, these are collectively referred to as “acrylic ester monomer”).
Is a polymer containing as a main component.

The acrylic ester monomer referred to in the present invention is an ester of acrylic acid or methacrylic acid with an aliphatic, alicyclic or aromatic unsubstituted alcohol.
Here, "unsubstituted" means having no groups other than the alcoholic hydroxyl group and the hydrocarbon group.

Examples of acrylic ester monomers include
Methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate,
Isobutyl (meth) acrylate, t (meth) acrylic acid
-Butyl, n-pentyl (meth) acrylate, (meth)
Isopentyl acrylate, n-hexyl (meth) acrylate, isohexyl (meth) acrylate, n-heptyl (meth) acrylate, isoheptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth)
N-octyl acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate, (meth) acrylic acid n-undecyl, (meth) acrylic acid n-dodecyl, (meth)
Examples thereof include palmityl acrylate, stearyl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate and the like. These acrylic ester monomers can be used alone or in admixture of two or more.

Of these acrylic ester monomers, alkyl (meth) acrylate having an alkyl group having 1 to 12 carbon atoms is preferable, and methyl methacrylate, n-butyl acrylate, 2-acrylic acid acrylate is more preferable. Ethylhexyl and isononyl acrylate.

The proportion of the acrylic ester monomer in all the monomers is 10 to 100% by weight, preferably 1
5 to 100% by weight, more preferably 20 to 98% by weight
Is. If the amount of the acrylic ester monomer used is less than 10% by weight, the weather resistance and water resistance of the primer will be insufficient, and the adhesion to the structural material will be reduced.

In the present invention, the other monomer that can form the polymer fine particle aqueous emulsion is a monomer that can be copolymerized with an acrylic ester monomer. Examples of such other monomers include aromatic vinyl monomers, vinyl cyanide monomers, hydroxyalkyl ester monomers of ethylenically unsaturated carboxylic acids or ester derivatives thereof, ethylenically unsaturated carboxylic acids. Acid amide monomer, ethylenically unsaturated acid monomer, ethylenically unsaturated sulfonic acid ester monomer, ethylenically unsaturated alcohol monomer or ester derivative thereof, ethylenically unsaturated ether monomer, ethylenic An unsaturated amine monomer, an ethylenically unsaturated silane monomer, a vinyl halide monomer, an aliphatic conjugated diene monomer, etc. are used.

Examples of the aromatic vinyl monomer include:
Styrene, α-methylstyrene, o-methylstyrene,
p-methylstyrene, o-ethylstyrene, p-ethylstyrene, α-chlorostyrene, p-chlorostyrene,
p-chloromethylstyrene, p-methoxystyrene, p
-Aminostyrene, p-dimethylaminostyrene, p-
Acetoxystyrene, sodium p-styrenesulfonate, α-vinylnaphthalene, β-vinylnaphthalene, 1
-Sodium vinylnaphthalene-4-sulfonate, 2-
Examples thereof include vinylfluorene, 2-vinylpyridine, 4-vinylpyridine and the like, and styrene is particularly preferable.

Examples of the vinyl cyanide-based monomer include (meth) acrylonitrile, α-chloroacrylonitrile, α-chloromethylacrylonitrile, α-methoxyacrylonitrile, α-ethoxyacrylonitrile and vinylidene cyanide. However, acrylonitrile is particularly preferable.

Examples of the hydroxyalkyl ester monomer of the ethylenically unsaturated carboxylic acid include hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 3-hydroxy. Examples thereof include propyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and particularly 2-hydroxyethyl (meth).
Acrylate is preferable, and examples of these ester derivatives include alkyl esters such as methyl ester and ethyl ester.

Examples of the ethylenically unsaturated carboxylic acid amide monomer include (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide,
N, N-diethyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, Nn-propoxymethyl (meth) acrylamide, Nn-butoxymethyl (meth) acrylamide, Examples thereof include N-methoxyethyl (meth) acrylamide, N-methoxyethyl (meth) acrylamide, Nn-propoxyethyl (meth) acrylamide and Nn-butoxyethyl (meth) acrylamide.

As the ethylenically unsaturated acid monomer,
Ethylenically unsaturated carboxylic acid, ethylenically unsaturated sulfonic acid and the like can be used. Examples of the ethylenically unsaturated carboxylic acid, (meth) acrylic acid, crotonic acid, fumaric acid, fumaric acid anhydride, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, citraconic acid,
Examples thereof include citraconic acid anhydride and mesaconic acid.
Particularly, (meth) acrylic acid is preferable, and examples of the ethylenically unsaturated sulfonic acid include vinyl sulfonic acid and isoprene sulfonic acid. These ethylenically unsaturated acid monomers may be neutralized with, for example, ammonia, alkali metal or the like. Examples of the ethylenically unsaturated sulfonic acid ester monomer include alkyl esters such as methyl vinyl sulfonate, ethyl vinyl sulfonate, methyl isoprene sulfonate, and ethyl isoprene sulfonate.

Examples of the ethylenically unsaturated alcohol monomer and its ester derivative are (meth) allyl alcohol, vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl laurate, vinyl stearate and benzoic acid. Vinyl, (meth) allyl acetate, (meth) allyl caproate, (meth) allyl laurate, (meth) allyl stearate, (meth) allyl benzoate, vinyl alkyl sulfonate, (meth) allyl alkyl sulfonate, aryl Vinyl sulfonate etc. can be mentioned.

Examples of the ethylenically unsaturated ether monomer include methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, methyl (meth) allyl ether, ethyl (meth) allyl ether and the like. .

Examples of the ethylenically unsaturated amine include vinyldimethylamine, vinyldiethylamine, vinyldiphenylamine, (meth) allyldimethylamine, (meth) allyldiethylamine and the like.

Examples of the ethylenically unsaturated silane include vinyltriethylsilane, methylvinyldichlorosilane, dimethyl (meth) allylchlorosilane, vinyltrichlorosilane and the like.

Examples of the vinyl halide monomer include vinyl chloride, vinylidene chloride, 1,2-dichloroethylene, vinyl bromide, vinylidene bromide, 1,2-dibromoethylene and the like.

Examples of the aliphatic conjugated diene monomer include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene and 2-neopentyl-1. , 3-butadiene, 2-chloro-1,3
-Butadiene, 1,2-dichloro-1,3-butadiene, 2,3-dichloro-1,3-butadiene, 2-bromo-1,3-butadiene, 2-cyano-1,3-butadiene, 1,3 -Pentadiene, 1,3-hexadiene and the like can be mentioned, with 1,3-butadiene being particularly preferred.

The above-mentioned other monomers may be used alone or in admixture of two or more, but the ethylenically unsaturated acid monomer and the monomer other than the ethylenically unsaturated acid monomer It is preferable to use and together.

The proportion of the other monomer in the total monomers is 0 to 90% by weight, preferably 0 to 85% by weight,
More preferably, it is 2 to 80% by weight. When the proportion of other monomers exceeds 90% by weight, the film forming property of the polymer fine particle aqueous emulsion is deteriorated, and the weather resistance and water resistance as a primer and the adhesion to a structural material are also insufficient. .

The polymer fine particle aqueous emulsion in the present invention is produced by a method of emulsion polymerizing an acrylic ester monomer together with other monomers from the viewpoint of uniformity of particle diameter, productivity and the like. It is preferable.
Hereinafter, the emulsion polymerization method for producing the polymer fine particle aqueous emulsion of the present invention will be described.

In the emulsion polymerization, an emulsifier composed of a hydrocarbon surfactant is usually used, and in the presence of a polymerization initiator, if necessary, a chain transfer agent, various electrolytes, a pH adjusting agent, etc. It is carried out by polymerizing a monomer composed of 10 to 100% by weight of an acrylic ester monomer and 90 to 0% by weight of another monomer.

As the hydrocarbon surfactant used in the emulsion polymerization, various emulsifiers such as anionic surfactant, nonionic surfactant, cationic surfactant and amphoteric surfactant can be used. , An anionic surfactant is preferable, and a strong acid type anionic surfactant is particularly preferable. Examples of the strong acid type anionic surfactant include sulfuric acid ester salts of higher alcohols, polyoxyethylene.
Alkyl ether sulfate, polyoxyethylene alkylphenyl ether sulfate, fatty oil sulfate, aliphatic amine or aliphatic amide sulfate, dibasic fatty acid ester sulfonate, aliphatic amide sulfone Acid salts, alkyl or alkenyl sulfonates, alkyl aryl sulfonates, alkyl sulfosuccinates, formalin condensed naphthalene sulfonates, phosphate ester salts of aliphatic alcohols, polyoxyethylene alkyl (phenyl) ether phosphate ester salts Etc. can be mentioned. Among these strong acid type anionic surfactants, sulfate ester salts or sulfonate salts, specifically, sodium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium diphenyl ether disulfonate, and sodium dialkyl ester sulfonate succinate are preferable.

Among the other hydrocarbon surfactants, the nonionic surfactants include polyoxyethylene alkyl ester, polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, glycerin fatty acid ester, sorbitan fatty acid ester,
Examples thereof include polyoxyethylene sorbitan fatty acid ester.

In the emulsion polymerization, it is possible to use a reactive emulsifier having one or more polymerizable unsaturated bonds. Examples of such reactive emulsifiers include emulsifiers represented by the following formulas (1) to (4).

[0029]

[Chemical 1]

[0030]

[Chemical 2]

[0031]

[Chemical 3]

[0032]

[Chemical 4]

[In the formulas (1) to (4), R ¹ , R ² , R ³
And R ⁴ is a higher alkyl group, n is an integer of 0 or more, M is 1
It is a cation of valence. ]

The amount of emulsifier used in the emulsion polymerization is
The stirring conditions and the like are adjusted according to the kind of the surfactant, the kind and the composition of the monomer, etc., and the selection is performed so as to obtain the required average particle size. The preferred amount of emulsifier used is generally 0.5 to 10% by weight, based on the total monomers. If the amount of the emulsifier used is less than 0.5 part by weight, the stability of the emulsion will be reduced due to the formation of coagulated substances, and it will be difficult to achieve the required particle size. , The adhesion to the structural material and the topcoat paint tends to decrease.

Polymerization initiators that can be used in the emulsion polymerization include persulfates such as potassium persulfate and ammonium persulfate, and inorganic initiators such as hydrogen peroxide;
Hydroperoxides such as cumene hydroperoxide, isopropylbenzene hydroperoxide and paramenthane hydroperoxide, dialkyl peroxides such as benzoyl peroxide, di-t-butyl peroxide and dilauroyl peroxide, sulfides, sulfinic acids, azo Examples thereof include organic initiators such as azo compounds such as bisisobutyronitrile, asobisisovaleronitrile, azobisisocapronitrile and azobis (phenylisobutyronitrile). The amount of these polymerization initiators used is preferably 0.03 to 2% by weight, and particularly preferably 0.05 to 1% by weight, based on all the monomers.

In the emulsion polymerization, a reducing agent or a chelating agent may be added to accelerate the polymerization. Examples of the reducing agent include sodium pyrobisulfite, sodium sulfite, sodium hydrogen sulfite, ferrous sulfate, glucose, formaldehyde sodium sulfoxylate, L-ascorbic acid and salts thereof, sodium hydrogen sulfite, and the like. Examples of the chelating agent include glycine, alanine, sodium ethylenediaminetetraacetate and the like.

As the chain transfer agent which can be used in the emulsion polymerization, α-methylstyrene dimer, terpinolene, α-terpinene containing 2,4-diphenyl-4-methyl-1-pentene component in an amount of 60% by weight or more. , Γ-terpinene, dipentene, octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, dimethylxanthogen disulfide, diethylxanthogen disulfide, diisopropylxanthogen disulfide, tetremethylthiuram monosulfide, tetraethylthiuram disulfide, tetrabutyl Examples thereof include thiuram disulfide and dipentamethyl thiuram disulfide. The amount of these chain transfer agents used is generally 15% by weight or less based on all monomers.

In the emulsion polymerization, generally 100 to 800 parts by weight of water is used with respect to 100 parts by weight of all monomers, and an emulsifier, a polymerization initiator and, if necessary, a chain transfer agent, a reducing agent and a chelating agent. , 10 to 90 ° C., preferably 40 to 80 ° C., using an appropriate amount of an electrolyte, a pH adjusting agent, etc.
The polymerization is carried out at a polymerization temperature of C, usually for 5 to 15 hours.

As a method of adding the monomers in the emulsion polymerization, an appropriate method such as a batch addition method, a divided addition method and a continuous addition method can be adopted, but a particularly preferable addition method is all monomers. Of the major proportion, preferably 90-
This is a method in which 100% by weight is added continuously or dividedly during the polymerization. In the case of continuous addition or divided addition, the monomer can be added together with other additive components such as a polymerization initiator, or the other additive components are added in advance in a total amount and only the monomer is added during the polymerization. It can be added. Further, the monomer added during the polymerization can be emulsified in advance.

In the polymer fine particle aqueous emulsion according to the present invention, the average particle size of the polymer fine particles is 0.003 to 0.
It is 1 μm, preferably 0.005 to 0.07 μm. The average particle size referred to here is a value obtained by treating a polymer fine particle emulsion with uranyl acetate and osmic acid, taking an electron micrograph of the emulsion, and averaging the particle sizes of 100 or more polymer fine particles. When the average particle size of the polymer fine particle aqueous emulsion exceeds 0.1 μm,
Permeability and adhesion to the structural material as a primer are reduced. Also, making the average particle size of the polymer fine particle aqueous emulsion smaller than 0.003 μm is
It becomes impractical to maintain a stable dispersion state of the emulsion. In order to bring the average particle size of the polymer fine particle aqueous emulsion in the present invention into the required range,
Depending on the type and amount of the emulsifier used, the viscosity of the monomer phase, etc., it is necessary to adjust the polymerization conditions such as the stirring method and stirring speed at the initial stage of polymerization, but the appropriate conditions are determined by experiments. It can be set sufficiently.

Further, the polymer fine particle aqueous emulsion in the present invention comprises acrylic ester monomer 10 to 100.
It can also be produced by inversion of a solution of a polymer of 90% by weight of another monomer and 90 to 0% by weight into an aqueous emulsion, and in that case, the addition amount of an emulsifier, stirring conditions, etc. are adjusted. As a result, an emulsion having a required average particle size can be obtained.

The polymer fine particle aqueous emulsion in the present invention has an average particle diameter of 0.12 to 0.12 of the average particle diameter of the acrylic resin emulsion used for the conventional aqueous primer.
It is extremely smaller than 0.2 μm, and is extremely excellent in adhesion to both the structural material and the topcoat paint.

The aqueous coating primer of the present invention may further contain a fluorochemical surfactant. As a result, the permeability of the polymer fine particle aqueous emulsion into the structural material is improved, the adhesion to the structural material as a primer is further improved, and the durability and water resistance to changes in environmental conditions such as temperature are also improved. More improved.

The fluorosurfactant has a lipophilic group composed of a fluorinated hydrocarbon, but its chemical structure is basically the same as that of the hydrocarbon surfactant.
Examples of the fluorinated surfactant include carboxylate group,
Anionic surfactants having anionic groups such as sulfate groups, sulfonate groups, and phosphate groups, nonionic surfactants having polyoxyethylene groups as hydrophilic groups, amine bases as hydrophilic groups, quaternary ammonium A cationic surfactant having a cationic group such as a base or an amphoteric surfactant can be used. Fluorosurfactants generally have high surface activity, and many of them exhibit a sufficient emulsifying action even if the lipophilic group has a smaller number of carbon atoms than ordinary surfactants.

Examples of the fluorine-based surfactants include perfluoroalkylcarboxylic acid salts, perfluoroalkyl group-containing sulfuric acid ester salts, perfluoroalkyl group-containing sulfonates, perfluoroalkyl group-containing sulfosuccinates, and perfluoroalkyl group-containing sulfosuccinates. Examples thereof include fluoroalkyl group-containing phosphate ester salts, perfluoroalkyltrialkylammonium salts, perfluoroalkylpolyoxyethylenes, perfluoroalkylbetaines and the like.

The content of the fluorinated surfactant is generally 0 to 5 parts by weight, preferably 0.01 to 100 parts by weight, based on 100 parts by weight of the polymer fine particle aqueous emulsion (solid content).
The amount is 1.0 part by weight, more preferably 0.02 to 0.5 part by weight. When the content of the fluorosurfactant exceeds 5 parts by weight, the performance improvement of the water-based primer commensurate with the cost increase cannot be achieved, and the water resistance of the primer is rather lowered.

Further, the aqueous coating primer of the present invention may contain an inorganic pigment, whereby the blocking resistance, matting property, reinforcing effect, etc. can be further improved.

Examples of the inorganic pigment include carbon black, titanium black, titanium oxide, calcium carbonate,
Examples thereof include aluminum hydroxide, zinc white, barium sulfate, gypsum, clay, silica and silica sand.

The content of the inorganic pigment is generally 0 to 100 parts by weight, preferably 5 to 70 parts by weight, based on 100 parts by weight of the polymer fine particle aqueous emulsion (solid content conversion).
More preferably, it is 10 to 50 parts by weight. If the content of the inorganic pigment exceeds 100 parts by weight, the adhesion with the structural material as a primer and the topcoat paint will deteriorate.

If desired, a silane compound can be added to the aqueous primer for coating of the present invention.
As a result, it is possible to further improve the adhesion to the structural material as the primer. Examples of the silane compound, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane,
Methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, isobutyltrimethoxysilane, isobutyl Triethoxysilane, n-
Hexyltrimethoxysilane, n-decyltrimethoxysilane, n-hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, hydroxypropyltrimethoxysilane, vinyl Trimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, 3,3,3-tolufluoropropyltrimethoxysilane, 3,3,3-tolufluoropropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-
Mercaptopropyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, γ-aminopropyltrimethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, 3,4-epoxycyclohexylethyltriethoxysilane, dimethyldimethoxysilane, Examples thereof include dimethyldiethoxysilane, diethyldimethoxysilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane and aminosilane. After addition, these silane compounds may be partially or wholly condensed.

Preferred silane compounds are tetramethoxylan, tetraethoxylan, methyltrimethoxysilane, methyltriethoxysilane, isobutyltrimethoxysilane, n-hexyltrimethoxysilane, dimethyldimethoxysilane and dimethyldiethoxysilane.

These silane compounds may be used alone or in the form of 2
It is possible to use a mixture of two or more species, and the addition amount is
It is generally 0.1 to 80 parts by weight per 100 parts by weight of the polymer fine particle aqueous emulsion (solid content conversion).

The coating water-based primer of the present invention may further contain, if necessary, other defoaming agents, antiseptics, antifungal agents, waterproofing agents, antiaging agents, ultraviolet absorbers, film forming aids, and the like. The properties can be optimized by blending the additive of.

The aqueous coating primer of the present invention can be widely applied to various structural materials and top coatings. Examples of such a structural material include cement-based materials such as cement concrete, cement mortar, polymer cement mortar, and slate; styrene resin, styrene-acrylonitrile resin, impact-resistant styrene resin, ABS resin, (meth) acrylic resin, acrylonitrile. Resin, vinyl chloride resin, vinylidene chloride resin, polyester resin, polycarbonate resin, polyamide resin, urethane resin, melamine resin, phenol resin, urea resin, epoxy resin and other synthetic resins; iron, steel, stainless steel, zinc, tin plate, copper ,aluminum,
Metals such as lead, wood, plywood, vulcanized rubber, glass, roof tile, plaster, ceramics, etc. can be mentioned, but the water-based primer for coating of the present invention is cement concrete, cement mortar, polymer cement mortar, slate, etc. When it is applied to the cement-based material, the above-mentioned effect is particularly remarkable.

As the top coat paint to be applied on the water-based primer for coating of the present invention, for example, vinyl acetate resin paint, vinyl chloride resin paint, acrylic resin paint,
Silicone acrylic resin-based paint, fluororesin-based paint, phenol resin-based paint, urea resin-based paint, melamine resin-based paint, (amino) alkyd resin-based paint, epoxy resin-based paint, unsaturated polyester resin-based paint, urethane resin-based paint , Synthetic rubber-based paints, chlorinated rubber-based paints, cyclized rubber-based paints, cellulose-based paints and the like. These top coats may be solvent type or emulsion type.

The present invention will be described in more detail with reference to the following examples and comparative examples. However, the present invention is not limited to these examples unless it exceeds the gist.

【Example】

Examples 1 to 5 and Comparative Examples 1 to 6 In a separable flask having an internal volume of 5 liters, the monomers and emulsifiers shown in Table 1 or Table 2 were used under a nitrogen gas atmosphere, and ammonium persulfate of 0.2% was used as a polymerization initiator. 5 copies,
After adding 0.02 part of sodium ethylenediaminetetraacetate as a chelating agent and a polymerization stabilizer to prepare an emulsion in 250 parts of water, the mixture was stirred at a polymerization temperature of 60.
At -80 ° C, emulsion polymerization was carried out while continuously adding the monomers during the polymerization to prepare a polymer fine particle aqueous emulsion. The polymerization conversion rates were all 99.5% or more, the emulsion stability was good, and almost no coagulated product was observed. Then, each polymer fine particle aqueous emulsion was added to Table 1
Alternatively, the formulation components shown in Table 2 were added to prepare an aqueous primer, and the following adhesion tests I to III were carried out. The test results are shown in Table 1 (Examples 1 to 5) and Table 2 (Comparative Examples 1 to 6).
Shown in.

Adhesion Test I (Structural Material / Primer) Each water-based primer was applied to a structural material composed of a slate plate, and
A brush was applied at a coating amount of 0 g / m ² and dried at room temperature for 48 hours to prepare a test object (I). Then, JISK540
In accordance with 0, 100 mm of 2 mm square grid is placed on the DUT (I).
Individual pieces were made and a peeling test using a cellophane tape (cross-grid test) was performed to calculate the number of cross-cuts remaining without peeling of the primer.

Adhesion Test II (Structural Material / Primer / Overcoat
Recoating material) To the test object (I) prepared in the adhesion test I, the top coating composition prepared as follows is roller-coated at a coating amount of 300 g / m ² and dried at room temperature for 72 hours to be tested. A body (II) was prepared. Then, a test piece (II) was subjected to a cross-cut test in accordance with JIS K5400 in the same manner as the adhesion test I. Here, the number of crosses in which neither the peeling of the structural material from the primer nor the peeling of the primer from the overcoat paint occurred was calculated.

(Preparation Method of Topcoat Paint) 20 parts by weight of titanium oxide, 2.0 parts by weight of 10% by weight sodium hexametaphosphate aqueous solution (dispersing agent), 2.0 parts by weight of 10% by weight aqueous solution of styrene maleic acid (dispersing agent) Parts, ethylene glycol (antifreezing agent) 0.29 parts by weight, antifoaming agent (solid content 50
A pigment paste was prepared by mixing 0.5% by weight, SN Deformer 381 (trade name), manufactured by San Nopco Ltd., and 2.0 parts by weight of water. This pigment paste 2
6.82 parts by weight of 70 parts by weight of a resin emulsion (solid content 50% by weight) of 2-ethylhexyl acrylate / n-butyl acrylate / methyl methacrylate / acrylic acid copolymer, a plasticizer (trade name: Texanol CS1)
2, 1.0 part by weight of Nitrogen Co., Ltd., an antifoaming agent (solid content 5)
0 wt%, trade name SN Deformer 381, manufactured by San Nopco Ltd.) 0.8 parts by weight and thickener (solid content 20 wt%, trade name Aron 20L, manufactured by Toagosei Chemical Industry Co., Ltd.)
A top coat was prepared by mixing with 1.0 part by weight.

Adhesion Test III (Structural Material / Primer / Upper
Coating composition ) The test object (II) prepared in the adhesion test II was immersed in water at 20 ° C for 18 hours, left in air at -20 ° C for 3 hours, and left in air at 50 ° C for 3 hours. After repeating the heating / cooling treatment for 5 cycles, a cross-cut test according to JIS K5400 was conducted in the same manner as the adhesion test II.

[0061]

[Table 1]

[0062]

[Table 2]

Reactive emulsifier (* 1) in Table 1 and Table 2
Is a sulfonate represented by the following formula (5).

[Chemical 5]

As is clear from Table 1, the water-based primer of the present invention was used for both the structural material and the overcoat paint.
Despite their completely different materials, they exhibit extremely high adhesion, and their adhesion can withstand repeated hot and cold treatments in water and air, as well as water resistance and chemical resistance. The weather resistance is also good. On the other hand, the monomer composition of the polymer fine particle aqueous emulsion,
If the average particle diameter, the content of the fluorine-based surfactant or the content of the inorganic pigment is out of the range of the present invention, the adhesiveness as a water-based primer for coating is insufficient.

[0065]

EFFECT OF THE INVENTION The water-based primer for coating of the present invention is excellent in adhesion to both the structural material and the top coating, and is also excellent in durability against changes in environmental conditions such as temperature and atmosphere. The properties and weather resistance are also good. Therefore, the coating water-based primer of the present invention can exhibit excellent functions for a long period of time as a primer for various structural materials and top-coat paints.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Yasuaki Yokoyama 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. An average particle diameter of a polymer comprising (A) 10 to 100% by weight of an acrylic acid ester monomer and / or methacrylic acid ester monomer and 90 to 0% by weight of another monomer. 100 parts by weight of polymer fine particle aqueous emulsion of 003 to 0.1 μm (as solid content), 0 to 5 parts by weight of (B) fluorosurfactant and (C) inorganic pigment of 0 to 10
A water-based primer for coating, which contains 0 part by weight.