JPH0881649A - Coating - Google Patents

Abstract

PURPOSE: To obtain a coating having excellent miscibility with pigment or inorganic filler, shelf stability at low temperatures, water resistance, resistance to contamination and thick-coating properties, etc., by including an aqueous emulsion comprising respectively specific dispersant and dispersoid as a principal component. CONSTITUTION: This coating contains an aqueous emulsion comprising (A) a modified PVA containing 1-10mol% <=4C α-olefin unit as a dispersant and (B) a (co)polymer of one or more monomers selected from ethylenic unsaturated monomers (e.g. vinyl ester) as a dispersoid. The component A is obtained, e.g. by saponifying a copolymer of a vinyl ester such as vinyl acetate and an α-olefin such as ethylene and has a degree of saponification of >=95mol% and a degree of polymerization of 300-2000. Preferably 2-30 pts.wt. of the component A is used to 100 pts.wt. of the component B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating material, and more specifically, it has excellent miscibility with pigments and inorganic fillers, water resistance, and
The present invention relates to a coating having excellent properties such as stain resistance and thick coating property.

[0002]

2. Description of the Related Art Conventionally, as exterior materials for the purpose of protecting building wall surfaces and the like, in addition to dry exterior materials such as decorative galvanized iron, printed plywood, various inorganic boards, and metal panels,
Wet exterior materials such as mortar finishing, tile application, and various coatings have been mainly used. However, in recent years, workability, economic efficiency, aesthetics, and the like have come to be emphasized, and the wet method has been remarkably popularized. This wet method is spraying,
It is widely used because it can efficiently coat a large area with a relatively simple work such as roll coating, has excellent waterproofness and durability, and is aesthetically preferable to various materials. Among the wet type exterior materials, mortar, tiled, inorganic spray material, etc. are gradually changing to paint-based spray exterior materials using an organic polymer as a binder in order to prevent accidents such as peeling and falling off from the wall surface. As the organic polymer, polymers such as epoxy type, urethane type, vinyl acetate type, acrylic acid ester type, and synthetic rubber type are used, but water-based binders are becoming mainstream due to recent pollution problems. Yes, and above all, emulsions of these polymers have been nominated. The main function of the exterior material is to beautify and protect the wall surface, but when the base material is concrete, etc., it prevents the spread of cracks to the paint protection surface due to base cracks (even if cracks occur in the base material. , No cracks in the coating film), waterproofing, etc. are also considered to be important properties.

In addition, other properties required of an aqueous emulsion as a coating binder include water resistance, stain resistance, and thick coatability. That is, conventionally, there has been a demand for a coating binder having each of the above properties. From the viewpoint of waterproofness and water resistance, in general, in the case of an aqueous emulsion containing a so-called “partially saponified” polyvinyl alcohol having a saponification degree of about 88 mol% as a dispersant, since the water absorption is large, whitening of the coating film due to water absorption, Since softening and blistering occur, and polyvinyl alcohol and the like are often eluted from the coating film, it is unsatisfactory in terms of the original purpose of the paint such as protection of the painted surface and beauty. The degree of saponification is 98 mol%
In the case of an aqueous emulsion having a degree of so-called "completely saponified" polyvinyl alcohol as a dispersant, various problems due to low water resistance such as the above partially saponified polyvinyl alcohol system are reduced, but viscosity stability at low temperature and pigment There is a problem of poor miscibility. Therefore, the conventional aqueous emulsions used as binders for coating materials have been mainly obtained by emulsion polymerization using various surfactants (emulsifiers) as dispersants, especially for exterior applications.

However, in the case of this emulsifier-based aqueous emulsion, although relatively good water resistance and water resistance can be obtained, if an attempt is made to soften the coating film to prevent cracks on the coating film surface, There is a problem that it causes an increase in tackiness and a decrease in stain resistance, and in general, an emulsifier-based aqueous emulsion has a small particle system, and therefore, when the coating film is thick, particles also tend to migrate in the water migration direction during the drying process. It has a drawback that the coating film is apt to be cracked due to a difference in film forming rate between the surface and the inside of the coating film as a result of migration. Furthermore, the miscibility with various pigments,
There is also a demand for improvement of mechanical stability during mixing and improvement of flow characteristics regarding leveling property during coating.

[0005]

Under the circumstances described above, the present invention is excellent in miscibility with various pigments, mechanical stability when admixed, and viscosity stability when left at a low temperature. It is an object to provide a paint having excellent properties such as water resistance, stain resistance, and pressure application property.

[0006]

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted extensive studies to develop a coating material having the above-mentioned preferable properties, and as a result, the dispersant has 1 .alpha.-olefin unit having 4 or less carbon atoms.
Found a coating containing an aqueous emulsion which is a modified polyvinyl alcohol containing 10 mol% and whose dispersoid is a (co) polymer of one or more monomers selected from ethylenically unsaturated monomers. The present invention has been completed.

The modified PVA containing 1 to 10 mol% of an α-olefin unit having 4 or less carbon atoms, which is used as a dispersant for an aqueous emulsion constituting the coating material of the present invention, is a copolymer of vinyl ester and α-olefin. Can be obtained by saponifying. Examples of the vinyl ester include vinyl formate, vinyl acetate, vinyl propionate, vinyl pivalate, etc., and vinyl acetate is economically preferable. The α-olefin of the present invention has 4 or less carbon atoms, and examples thereof include ethylene, propylene, n-butene, and isobutene, and ethylene is preferable from the viewpoint of water resistance of the obtained aqueous emulsion film. It is necessary that the content of α-olefin is 1 to 10 mol%, preferably 2 to 8 mol%. When the content of α-olefin is less than 1 mol%, the above-mentioned remarkable effects cannot be obtained, and when it exceeds 10 mol%, the water solubility is decreased and a stable aqueous emulsion cannot be obtained. The above effect cannot be obtained.

Further, the dispersant may be a copolymer of an ethylenically unsaturated monomer copolymerizable within a range not impairing the effects of the present invention. Examples of such ethylenically unsaturated monomers include acrylic acid, methacrylic acid, (anhydrous) phthalic acid, (anhydrous) maleic acid, (anhydrous) itaconic acid, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, Trimethyl- (3-acrylamido-3-dimethylpropyl) -ammonium chloride, acrylamido-2-methylpropanesulfonic acid and its sodium salt, ethyl vinyl ether, butyl vinyl ether, N-vinyl pyrrolidone, vinyl chloride, vinyl bromide, vinyl fluoride. , Vinylidene chloride, vinylidene fluoride, tetrafluoroethylene, sodium vinyl sulfonate, sodium allyl sulfonate and the like. Further, it is obtained by copolymerizing a vinyl ester monomer such as vinyl acetate with an α-olefin having 4 or less carbon atoms in the presence of a thiol compound such as thiolacetic acid or mercaptopropionic acid, and saponifying it. A terminal modified product can also be used.

The degree of saponification of the modified PVA containing 1 to 10 mol% of an α-olefin having 4 or less carbon atoms, which is used as a dispersant for the aqueous emulsion constituting the coating material of the present invention, depends on the α-olefin content. Mol% or more is preferable,
90 mol% or more is more preferable, and 95 mol% or more is still more preferable. The degree of polymerization of the PVA is 100-80.
00 is preferable, and 300 to 2000 is more preferable.

The (co) ethylenically unsaturated monomer that is the dispersoid in the aqueous emulsion that constitutes the coating material of the present invention.
Although there are various polymers, preferred examples of the ethylenically unsaturated monomer as a raw material of this (co) polymer are olefins such as ethylene, propylene and isobutylene, vinyl chloride, vinyl fluoride, Halogenated olefins such as vinylidene chloride, vinylidene fluoride, vinyl formate, vinyl acetate, vinyl propionate, vinyl esters such as vinyl versatate, acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, acrylic acid 2-ethylhexyl, dodecyl acrylate, acrylic acid ester such as 2-hydroxyethyl acrylate, methyl methacrylate,
Methacrylic acid esters such as ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, 2-hydroxyethyl methacrylate, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate and their quaternized products, and further , Acrylamide, methacrylamide, N-methylolacrylamide, N, N-dimethylacrylamide,
Acrylamide-based monomers such as acrylamido-2-methylpropanesulfonic acid and its sodium salt, styrene-based monomers such as styrene, α-methylstyrene, p-styrenesulfonic acid and sodium and potassium salts,
Others such as N-vinylpyrrolidone, butadiene,
Examples thereof include diene-based monomers such as isoprene and chloroprene, which may be used alone or in combination of two or more. Among the above-mentioned ethylenically unsaturated monomers, vinyl ester, (meth) acrylic acid ester, styrene and diene-based monomers are preferable, and particularly vinyl ester, a combination of ethylene and vinyl ester, and vinyl ester and (meth) acryl. The combined use of acid esters is preferred.

The aqueous emulsion in the coating composition of the present invention uses the above-mentioned aqueous solution of PVA having an α-olefin unit having 4 or less carbon atoms as a dispersant in the presence of a polymerization initiator to obtain the above ethylenically unsaturated monomer. It is obtained by emulsion polymerization of the ethylenically unsaturated monomer by adding the body temporarily or continuously. In addition, the ethylenically unsaturated monomer,
Modified P having an α-olefin unit having 4 or less carbon atoms in advance
An emulsion polymerization method in which an emulsion obtained by using an VA aqueous solution is continuously added to the polymerization reaction system can also be adopted. The amount of the α-olefin-modified PVA used is not particularly limited, but is preferably 1 to 30 parts by weight, more preferably 2 to 20 parts by weight with respect to 100 parts by weight of the polymer of the ethylenically unsaturated monomer. It is a range. When the amount used is less than 1 part by weight or more than 30 parts by weight, the polymerization stability may be lowered or the water resistance may be lowered.

As the polymerization initiator, ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide,
t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, benzoyl peroxide, ammonium peroxoborate, azobisisobutyronitrile, 2,2-azobis (2-amidinopropane) dihydrochloride, etc. Known polymerization initiators can be used. These polymerization initiators may be used alone, or by combining with a reducing agent such as sodium bisulfite, tartaric acid, citric acid, glucose, L-ascorbic acid, sodium formaldehyde sulfoxylate, and iron ion, redox It may be used in the system.
The amount and method of use of the polymerization initiator may be those conventionally known.

The following conventionally known surfactants may be added to the aqueous emulsion of the present invention before the initiation of emulsion polymerization, during emulsion polymerization or after emulsion polymerization. As the surfactant, potassium oleate, potassium castor oil, semi-hardened tallow fatty acid sodium, semi-hardened tallow fatty acid potassium, sodium lauryl sulfate, triethanolamine lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium alkylnaphthalenesulfonate. , Sodium alkyl diphenyl ether disulfonate, potassium alkyl phosphate, sodium salt of β-naphthalene sulfonic acid formalin condensate, sodium salt of aromatic sulfonic acid formalin condensate, sodium polyoxyethylene lauryl ether sulfate, polyoxyethylene alkylphenyl ether sulfate Sodium, sodium bistridecyl sulfosuccinate, sodium dioctyl sulfosuccinate, sodium dihexyl sulfosuccinate Beam, sodium dicyclohexyl sulfosuccinate,
Sodium diamyl sulfosuccinate, sodium diisobutyl sulfosuccinate, sodium isodecyl sulfosuccinate, disodium sulfosuccinate ethoxylated alcohol half ester, sulfosuccinate disodium ethoxylated nonylphenyl half ester, N- (1,2-dicarboxyethyl)- Anionic surfactants such as tetrasodium N-octadecylsulfosuccinamide, disodium N-octadecylsulfosuccinamide, sodium diisopropylnaphthalenesulfonate, sodium tripolyphosphate, sodium hexametaphosphate; polyoxyethylene lauryl ether, polyoxyethylene cetyl ether , Polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl ether Nonyl ether, polyoxyethylene nonylphenyl ether, oxyethylene-oxypropylene block polymer, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, fatty acid monoglyceride, polyethylene glycol fatty acid ester, polyoxyethylene lauryl amine, polyoxyethylene stearyl amine Cationic surfactants; cationic surfactants such as stearylamine acetate, lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, distearyldimethylammonium chloride, alkylaminganidinium polyoxyethanol, alkylbenzyldimethylammonium chloride; laurylbetaine, stearylbetaine , Lauryl dimethy LATEMUL introducing the double bond in addition the above surfactants S-; amine oxide, amphoteric surfactants such as lauryl carboxymethyl hydroxyethyl imidazolinium betaine
180, S-120 (above, Kao Corporation make), ADEKA rear soap NE-10, ADEKA rear soap NE-20,
ADEKA Rear Soap NE-30, ADEKA Rear Soap SE-
10N (above, Asahi Denka Co., Ltd.), Eleminor JS
-2 (manufactured by Sanyo Kasei Co., Ltd.), Aqualon RN-20,
Reactive surfactants such as Aqualon HS-10 (all manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) can be mentioned. When the surfactant is added, it is added in an amount of 0 to 10 parts by weight (preferably 0.1 to 10 parts by weight, more preferably 0.1 to 100 parts by weight) per 100 parts by weight of the monomer (polymer of dispersoid). 5 to 5 parts by weight, and even more preferably 1 to 5 parts by weight).

The following publicly known plasticizers or film-forming aids may be added to the aqueous emulsion of the present invention during or after the emulsion polymerization. As a plasticizer or a film-forming aid, dimethyl phthalate, diethyl phthalate, diamyl phthalate, dibutyl phthalate (DB
P), tributyl acetyl citrate, diisobutyl adipate, dibutyl sebacate, dimethyl glycol adipate, diethyl glycol adipate, dibutyl glycol adipate, dimethyl glycol sebate, diethyl glycol sebate, dimethyl glycol phthalate, diethyl glycol phthalate, dibutyl glycol phthalate, Tricresyl phosphate, dioctyl phthalate, texanol, polyethylene glycol monophenyl ether, polypropylene glycol monophenyl ether, benzyl alcohol, butyl carbitol acetate, butyl carbitol, 3-methyl-3-methoxybutanol, ethylene glycol, acetylene glycol butyl cellosolve , Ethylene cellosolve, bife chloride Lumpur, and the like.

When a plasticizer or a film-forming aid is added, it is added in an amount of 0 to 200 parts by weight (preferably 1 to 100 parts by weight, based on 100 parts by weight of the monomer (polymer of dispersoid)). More preferably 5 to 20 parts by weight).

The coating composition of the present invention may contain a pigment, if desired. Here, the pigment is not particularly limited, and various natural pigments, synthetic inorganic pigments and synthetic organic pigments can be used. Furthermore, specifically, coloring pigments (titanium oxide, titanium white, iron oxide, iron yellow, ultramarine blue, cadmium yellow, red iron oxide, chrome yellow, carbon black, cyanine pigments, azo pigments, triphenylmethane pigments, quinoline Pigments, anthraquinone pigments, phthalocyanine pigments, etc., extender pigments (barium sulfate, calcium carbonate, kaolin clay, wax stone clay, talc, silica, alumina, perlite, silica sand,
Bentonite, calcium silicate, aluminum silicate, diatomaceous earth, silica, anhydrous silicic acid, hydrous silicic acid, magnesium carbonate, aluminum hydroxide, barium sulfate,
Calcium sulfate, etc., special pigments (rust preventive pigments, luminescent pigments, thermochromic pigments, etc.), fibrous or scaly special inorganic pigments (asbestos, rock wool, mica, etc.), others, pulp, various resin powders, sericite, Examples include carbon black. These pigments may be used alone or in combination of two or more.

The amount of the pigment blended is not particularly limited, but is preferably 40 to 400 parts by weight, more preferably 60 to 300 parts by weight, based on 100 parts by weight of the dispersoid polymer of the aqueous emulsion. If the amount of the pigment added is less than 40 parts by weight, the coating film may have a problem such as blistering. On the other hand, if it exceeds 400 parts by weight, the coating film may lose flexibility or elasticity.

To the aqueous emulsion of the present invention, the following conventionally known extenders may be added after emulsion polymerization.
As the filler, casein, glue, gelatin, gluten, soybean protein, ammonium alginate, potassium alginate, sodium alginate, arabic gum, tragacanth gum, karaya gum, guar gum, locust bean gum, Irish moss, soybean lecithin, pectic acid, starch, agar. , Bentonite clay, ammonium polyacrylate, sodium polyacrylate, polyacrylic acid, ammonium polymethacrylate, polyvinyl alcohol, modified poly (vinyl methyl ether / maleic anhydride), polyvinylpyrrolidone, polyacrylamide,
Examples thereof include polyethylene oxide, carboxylated methyl cellulose, methyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl cellulose, cellulose xanthate, carboxylated starch, ammonium oleate, and sodium silicate. When the filler is added, it is added in an amount of 0.1 to 100 parts by weight (preferably 0.5 to 50 parts by weight) based on 100 parts by weight of the dispersoid polymer.
Parts by weight, more preferably 1 to 20 parts by weight).

The aqueous emulsion used in the present invention is
The aqueous emulsion obtained by the above method may be used as it is, but if necessary, various conventionally known emulsions can be added within a range that does not impair the effects of the present invention.

The coating composition of the present invention contains an antifoaming agent, an antifungal agent, an antiseptic agent, an antiaging agent, as long as the object of the present invention is not impaired.
Antifreeze agents and the like can be added.

The paint of the present invention is applied by a general method using a roll, a trowel, a brush, a spray gun or the like. Further, it can be suitably used for various surfaces such as wall surfaces, floor surfaces and ceiling surfaces made of concrete, mortar, ALC plate, flexible plate, metal plate, plywood and the like. At this time, for the purpose of improving the adhesion to the base, waterproofness, weather resistance, aesthetics, etc., a base treatment agent, a top coat agent, etc. can be used.

[0022]

The present invention will be described in more detail with reference to Examples and Comparative Examples. In the following Examples and Comparative Examples, "part" and "%" mean weight basis unless otherwise specified. In addition, the performance of the paint, that is, the pigment
The inorganic filler miscibility, low temperature viscosity stability, pressure application property, tackiness (contamination resistance) and water resistance were measured in the following manner.

(1) Miscibility of Pigment and Inorganic Filler The dispersion state when the pigment and the inorganic filler were added to the aqueous emulsion was evaluated according to the following criteria in three grades. ○: Good dispersion condition △: Viscosity increased ×: Coagulated product with a gritty feel

(2) Low Temperature Viscosity Stability The state in which the paint was left in a constant temperature bath at 5 ° C. for 1 month was evaluated according to the following criteria on a three-point scale. ◯: Almost no change from before standing Δ: Viscosity increased ×: Gelation

(3) Pressing property The paint is sprayed onto an asbestos slate plate (with a deviation diameter of 6.5 m).
m, weight of spraying pressure of 3 kg / cm ² ) about 2.0
Spray at a weight of kg / cm ² and run at 20 ° C for 7
Allowed to dry for days. The state of the coating surface of this paint spraying plate was observed and evaluated on the basis of the following criteria in three levels. ◯: Smooth coating film formation △: Slightly uneven coating film formation ×: Cracks in coating film

(4) Adhesiveness (stain resistance) A defoamed paint was applied on a glass plate so that the film thickness after drying would be 2 mm, dried at room temperature for 3 days, and then peeled off from the glass plate. Then, it was turned over and dried for another 4 days. The tack of the surface of the test body thus obtained was judged by the finger touch method according to the following criteria. ○: Almost no tackiness ×: Great tackiness

(5) Water resistance After the defoaming paint was applied on a glass plate so that the film thickness after drying would be 2 mm, it was dried at room temperature for 3 days, then peeled off from the glass plate and turned inside out to further 4 It was dried for a day. The test piece thus obtained was immersed in running water at 20 ° C. for 24 hours, and the condition was observed and evaluated according to the following criteria. ○: Almost no change △: Coating swells ×: Coating swells, re-emulsifies and breaks

Example 1 A 1-liter glass polymerization vessel equipped with a reflux condenser, a dropping funnel, a thermometer, and a nitrogen blowing port was charged with ion-exchanged water 400.
g, ethylene-modified PVA (polymerization degree 1400, saponification degree 9
8.5 mol%, ethylene 4.5 mol% modified) 40 g
Was charged and completely dissolved at 95 ° C. Next, after cooling this PVA aqueous solution and replacing with nitrogen, 40 g of vinyl acetate was charged while stirring at 140 rpm, the temperature was raised to 60 ° C., and then polymerization was initiated in the presence of a hydrogen peroxide / tartaric acid redox initiator system. . 15 minutes after the initiation of the polymerization, 360 g of vinyl acetate was continuously added over 3 hours to complete the polymerization.
Solid content concentration 50.4%, viscosity 4500 mPa.s. A stable polyvinyl acetate emulsion of s was obtained. 1 part of dibutyl phthalate to 100 parts of solid content of this emulsion
0 parts, 3 parts of 3% sodium hexametaphosphate aqueous solution, 2 parts of 3% aqueous solution of Metroose 15000 (manufactured by Shin-Etsu Chemical Co., Ltd., methylcellulose) and 0.5 parts of Nopco 8034 (manufactured by San Nopco, antifoaming agent) were added, and further heavier 56 parts of calcium carbonate (Shiroishi Industry Co., Ltd., Whiten P-40),
16.5 parts of rutile type titanium oxide and 37.5 parts of talc were added and mixed uniformly. The performance of the coating material thus obtained was evaluated. The results are shown in Tables 1-2.

Comparative Example 1 Instead of the ethylene-modified PVA used in Example 1, unmodified PVA (polymerization degree 1400, saponification degree 98.5 m) was used.
ol%) in the same manner as in Example 1 except that 40 g is used,
Solid content concentration 50.3%, viscosity 4000 mPa.s. A stable polyvinyl acetate emulsion of s was obtained. Using this, evaluation was performed in the same manner as in Example 1.

Comparative Example 2 Instead of the ethylene-modified PVA used in Example 1, unmodified PVA (polymerization degree 1400, saponification degree 88.2 m) was used.
ol%) in the same manner as in Example 1 except that 40 g is used,
Solid content concentration 50.2%, viscosity 13000 mPa.s. A stable polyvinyl acetate emulsion of s was obtained. Using this, evaluation was performed in the same manner as in Example 1.

Comparative Example 3 Instead of the ethylene-modified PVA used in Example 1, ethylene-modified PVA (polymerization degree 1400, saponification degree 9
Emulsion polymerization of vinyl acetate was carried out in the same manner as in Example 1 except that 40 g of (8.5 mol%, modified with 11 mol% of ethylene) was used. This ethylene-modified PVA was not completely dissolved in water, and gelled and solidified during the emulsion polymerization.

Comparative Example 4 Instead of the ethylene-modified PVA used in Example 1, ethylene-modified PVA (polymerization degree 1400, saponification degree 9) was used.
8.5 mol%, ethylene 0.5 mol% modified) 40 g
The solid content concentration is 5 in the same manner as in Example 1 except that
0.3%, viscosity 4200 mPa.s. A stable polyvinyl acetate emulsion of s was obtained. Using this, evaluation was performed in the same manner as in Example 1.

Example 2 Ethylene-modified PVA (polymerization degree 1750, saponification degree 98.7)
21 g of (mol%, modified with 3.0 mol% of ethylene) was dissolved in 290 g of ion-exchanged water by heating, and the solution was placed in a pressure-resistant autoclave equipped with a nitrogen inlet and a thermometer. After adjusting the pH to 4 with dilute sulfuric acid, 300 g of vinyl acetate was charged, and then ethylene was pressurized to 45 kg / cm ² G (ethylene copolymerization amount corresponds to 60 g). After the temperature was raised to 60 ° C., polymerization was initiated with hydrogen peroxide / Rongalite redox initiator. After 2 hours, the polymerization was terminated when the residual vinyl acetate concentration reached 0.6%. Solid content concentration 52.6%, viscosity 6300 mPa.s. A stable poly (ethylene-vinyl acetate) copolymer emulsion of s was obtained. To 100 parts by weight of the solid content of this emulsion, 3 parts of a 3% aqueous solution of sodium hexametaphosphate, 2 parts of a 3% aqueous solution of Metroses 15000 (manufactured by Shin-Etsu Chemical Co., Ltd.) and Nopco 8034 (a defoaming agent manufactured by San Nopco) 0.5 56 parts of heavy calcium carbonate (Shiraishi Kogyo KK, Whiten P-40), 16.5 parts of rutile titanium oxide and 37.5 parts of talc,
Mix evenly. The performance of the coating material thus obtained was evaluated. The results are shown in Tables 1-2.

Comparative Example 5 Instead of the ethylene-modified PVA used in Example 2, unmodified PVA (polymerization degree 1700, saponification degree 98.6 m) was used.
ol%) in the same manner as in Example 2 except that 21 g is used,
Solid content concentration 52.4%, viscosity 6000 mPa.s. A stable polyvinyl acetate emulsion of s was obtained. This was used and evaluated in the same manner as in Example 2.

Example 3 A 1 liter glass-made polymerization vessel equipped with a reflux condenser, a dropping funnel, a thermometer, and a nitrogen blowing port was charged with 400 parts of ion-exchanged water.
g, ethylene-modified PVA (polymerization degree 1000, saponification degree 9
5.0 mol%, ethylene 6.0 mol% modified) 36 g
Was charged and completely dissolved at 95 ° C. Next, after cooling this PVA aqueous solution and replacing with nitrogen, while stirring at 140 rpm, 32 g of vinyl acetate and 8 g of n-butyl acrylate were charged, the temperature was raised to 70 ° C., and then polymerization was started using potassium persulfate as an initiator. did. After the generation of heat was confirmed by the start of polymerization, vinyl acetate 288 g and n-butyl acrylate 7
2 g was continuously added over 3 hours to complete the polymerization. Solid content concentration 50.0%, viscosity 2000 mPa.s. A stable poly (vinyl acetate-n-butyl acrylate) copolymer emulsion of s was obtained. Sodium hexametaphosphate 3% based on 100 parts by weight of the solid content of this emulsion
3 parts aqueous solution, 2 parts 3% aqueous solution of Metroses 15000 (manufactured by Shin-Etsu Chemical Co., Ltd., methylcellulose) and Nopco 8034
0.5 part (manufactured by San Nopco, defoamer) was added, and further heavy calcium carbonate (manufactured by Shiraishi Kogyo, Whiten P-4).
0) 56 parts, rutile type titanium oxide 16.5 parts and talc 37.5 parts were added and uniformly mixed. The performance of the coating material thus obtained was evaluated. The results are shown in Tables 1-2.

Comparative Example 6 In place of the ethylene-modified PVA used in Example 3, unmodified PVA (polymerization degree 1000, saponification degree 95.0 m
0%) in the same manner as in Example 3 except that the solid content concentration is 50.2% and the viscosity is 2200 mPa.s. A stable poly (vinyl acetate-n-butyl acrylate) copolymer emulsion of s was obtained. This was used and evaluated in the same manner as in Example 3.

[0037]

[Table 1]

* 1: Polymerization degree 1400, saponification degree 98.5 mo
1%, ethylene 4.5 mol% modified * 2: degree of polymerization 1400, degree of saponification 98.5 mol% * 3: degree of polymerization 1400, degree of saponification 88.2 mol% * 4: degree of polymerization 1400, degree of saponification 98.5 mol%, ethylene 11.0 mol% modification * 5: Polymerization degree 1400, saponification degree 98.5 mol%, ethylene 0.5 mol% modification * 6: Polymerization degree 1750, saponification degree 98.7 mol%, ethylene 3.0 mol% modification * 7: Polymerization degree 1700, saponification degree 98.6 mol% * 8: degree of polymerization 1000, saponification degree 95.0 mol%, ethylene 6.0 mol% modification * 9: degree of polymerization 1000, saponification degree 95.0 mol%

[0039]

[Table 2]

[0040]

The coating material of the present invention is excellent in miscibility with pigments and inorganic fillers, stability at low temperature storage, and is excellent in water resistance, stain resistance, thick coating property and the like.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoki Fujiwara 1621 Sakata, Kurashiki City, Okayama Prefecture Kuraray Co., Ltd.

Claims (1)

[Claims] 1. A dispersant is a modified polyvinyl alcohol containing 1 to 10 mol% of an α-olefin unit having 4 or less carbon atoms, and the dispersoid is one or more selected from ethylenically unsaturated monomers. A paint containing an aqueous emulsion which is a (co) polymer of monomers.