JPH07316486A - Composition for coating vinyl chloride resin molding and method of coating molding therewith - Google Patents

Abstract

PURPOSE:To obtain the title composition which can prevent the plasticizer from bleeding to the surface of the molding to make the surface proof against staining with dust, oil a water-base ink, food or the like and is excellent in adhesion to a vinyl chloride resin molding, weatherability, high-frequency weldability, etc. CONSTITUTION:This composition is one used as a top-coating composition for a primed vinyl chloride resin molding and comprising a soft fluororesin comprising a fluororubber and a vinylidene fluoride resin and a copolymer of a monomer having a quat. ammonium halide group represented by formula I (R1, R2 and R3 are each an alkyl, and Y is a halogen) and an alpha,beta-ethylenically unsaturated group represented by formula II (R4 is hydrogen or methyl) with another alpha,beta-ethylenically unsaturated monomer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for topcoating a vinyl chloride resin molded article having an excellent antifouling function, and a method for coating a vinyl chloride resin molded article using the same.

[0002]

2. Description of the Related Art Vinyl chloride resins are used in various fields from hard to soft by changing the amount of plasticizer. For example, it is used in many applications such as hard pipes, plates and soft films, sheets, leather, tents, pan cloths, tarpaulins, wall materials and daily necessities. By the way, a molded article produced by using a vinyl chloride-based resin mixed with a plasticizer has dust, dust, dust, and the like because the plasticizer bleeds on its surface.
When dust such as soot and the like, oil-based inks, water-based inks, foodstuffs, etc., which are routinely used at home adhere, the molded product is contaminated. In order to eliminate such a defect, it has been proposed to provide a resin coating layer for suppressing the migration of the plasticizer on the surface of the vinyl chloride resin molded article, and a part thereof has already been put into practical use. As a resin for forming a resin coating layer, a homopolymer of a conventional acrylic acid ester monomer or a methacrylic acid ester monomer, or a copolymer of a vinyl-based monomer copolymerizable therewith (Japanese Patent Publication No.
No. 28740), but various properties such as stain resistance, crack resistance, and weather resistance have not been sufficiently satisfied. Further, in JP-A-62-169641, a vinylidene fluoride resin is prepared by coating a copolymer of a fluorine-containing unsaturated ester and a fluorine-free copolymerizable monomer on the surface of a vinyl chloride resin molded article. It has been proposed to coat with a coating composition mixed in. This coating composition is effective in terms of dust contamination, but it is oil-based ink,
It is not sufficient to contaminate water-based inks, foods, etc., and the coating film has poor resistance to rubbing, resulting in poor crack resistance. In addition, JP-A-2-2998
No. 38 and Japanese Patent Application Laid-Open No. 2-299839 disclose
It has been shown that a vinyl chloride resin sheet can be provided with a sheet having excellent adhesiveness by forming a coating film containing a fluorine-containing copolymer having a crosslinked portion and an acrylic copolymer as the main components, However, since the coating film forming agent is a two-component curing type, there is a limitation in working time and a slow curing speed, and there is a limitation in workability, which is not practical. Further, since the coating film is cross-linked, there is a problem that the high-frequency bonding process used for bonding vinyl chloride resin molded products to each other cannot be applied, and thus the range of applications is limited.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art, and its purpose is to prevent bleeding of the plasticizer and to prevent dust on the surface of the molded product. We provide a coating composition that can prevent stains and oil-based inks, water-based inks, stains caused by daily necessities such as food products, and that have excellent adhesion to vinyl chloride resin molded products, weather resistance, resistance to rubbing, and high-frequency adhesion. To do. Another object of the present invention is to provide a method for coating a vinyl chloride resin molded article with the above coating composition.

[0004]

A primer coating composition for a vinyl chloride resin molded article treated with a primer of the present invention comprises a soft fluororesin (A) containing a fluororubber and a vinylidene fluoride resin as constituent components, and a molecule. In the general formula

[Chemical 3] (In the formula, R ₁ , R ₂ and R ₃ each represent an alkyl group, preferably an alkyl group having 1 to 2 carbon atoms, and Y represents a halogen atom.) And a quaternary ammonium halide group represented by general formula formula

[Chemical 4] (In the formula, R ₄ represents a hydrogen atom or a methyl group) and a monomer (a) having an α, β-ethylenically unsaturated group and another α, β-ethylenically unsaturated monomer. It is characterized by comprising a copolymer (B) with the body (b). Further, the method for coating a vinyl chloride resin molded article of the present invention is a method of treating a vinyl chloride resin molded article with a primer composition comprising an acrylic polymer or copolymer or a mixture thereof with a vinyl chloride resin. Then, it is treated with the composition for overcoating according to claim 1.

The present invention will be described below. The soft fluororesin (A) which is a main component constituting the overcoat coating composition of the present invention contains a fluororubber and a vinylidene fluoride resin as constitutional components and is soluble in dimethylformamide (DMF). It is a thing. Specifically, a block copolymer of fluororubber and a vinylidene fluoride polymer (for example, Daier Thermo T-630, manufactured by Daikin Industries, Ltd.) and a graft copolymer obtained by grafting a vinylidene fluoride polymer on the fluororubber (for example, , Cefral Soft G-180, manufactured by Central Glass Co., Ltd., and the like. These soft fluororesins are DMF alone or DMF.
And other solvents such as toluene, xylene, methyl ethyl ketone (MEK), methyl isobutyl ketone, ethyl acetate, cyclohexane, etc., can be easily dissolved in a mixed solvent containing 40% by weight or more of DMF to elongate the coating film. Is also 300 to 800%, and has better flexibility than vinylidene fluoride resin. Further, these soft fluororesins have excellent antifouling performance, and are superior in antifouling properties and weather resistance as compared with other resins having the same degree of elongation of the coating film.

The copolymer (B) which is the other main component constituting the overcoat coating composition of the present invention is represented by the above general formula (1).
A monomer (a) having a quaternary ammonium halide group represented by and an α, β-ethylenically unsaturated group represented by the general formula (2), and another α, β-ethylenically unsaturated monomer A copolymer with the body (b) (hereinafter referred to as "quaternary ammonium halide group-containing copolymer"), wherein the monomer (a) is 2-hydroxy-3-methacryloyloxypropyltrimethyl. Ammonium halide, 2-
Examples thereof include methacryloyloxyethyltrimethylammonium halide, vinyltrimethylammonium halide, vinyltriethylammonium halide, allyltrimethylammonium halide, vinylbenzyltrimethylammonium halide and N- (3-acrylamidopropyl) trimethylammonium halide.

Further, another α, which can be copolymerized with the above-mentioned monomer,
As the β-ethylenically unsaturated monomer (b), acrylic acid, methacrylic acid or alkyl esters thereof,
Acrylamide, methacrylamide, acrylonitrile, glycidyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate,
2-hydroxypropyl methacrylate, vinyltoluene, vinylpyridine, N-vinylpyrrolidone and the like can be mentioned.

The content of the monomer (a) having the quaternary ammonium halide group and the α, β-ethylenically unsaturated group in the quaternary ammonium halide group-containing copolymer (B) is 1 to 20. % By weight, preferably 3
10 to 10% by weight. If the content is less than 1% by weight, the compatibility with the soft fluororesin is poor and the content is 20% by weight.
When it is higher, the water resistance and weather resistance are inferior, which is not preferable. The quaternary ammonium halide group-containing copolymer (B) has excellent compatibility with the soft fluororesin,
In addition, it exhibits a very excellent bleed prevention effect against the plasticizer contained in the vinyl chloride resin.

The quaternary ammonium halide group-containing copolymer (B) can be obtained by ordinary solution polymerization. For example, a quaternary ammonium halide group and α,
The monomer (a) having a β-ethylenically unsaturated group is charged into a solvent and heated at 60 to 80 ° C. to dissolve, and another α, β-
An ethylenically unsaturated monomer is charged, and a polymerization catalyst is added and polymerized under a nitrogen gas atmosphere. Suitable solvents include dimethylformamide or other solvents, for example, alcohols such as methanol and ethanol, ketones such as methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, ether alcohols such as methyl cellosolve and butyl cellosolve. It is possible to use a mixed solvent prepared by mixing one kind or two kinds or more of acid amides such as compounds, dimethylformamide and acetamide. As the polymerization catalyst, commonly used peroxide catalysts such as benzoyl peroxide and ditertiary-butyl peroxide, and catalysts such as asobisisobutyronitrile are used. The concentration at the time of polymerization is suitably in the range of 20-40% by weight.

In the above-mentioned overcoating composition of the present invention, the mixing ratio of the soft fluororesin (A) and the quaternary ammonium halide group-containing copolymer (B) is 100 parts by weight of the soft fluororesin (A). On the other hand, the range of 50 to 200 parts by weight of the quaternary ammonium halide group-containing copolymer (B) is suitable, and the range of 100 to 150 parts by weight is preferable. If the mixing ratio of the quaternary ammonium halide group-containing copolymer (B) is less than 50 parts by weight, the antifouling property is lowered, and if it is more than 200 parts by weight, the crack resistance is inferior.

The topcoat coating composition of the present invention also comprises
For the purpose of imparting water repellency and oil repellency, silicone oil, fluorine oil or the like may be added. Further, a matting agent such as silica or an organic filler may be mixed and dispersed for the purpose of obtaining a matte appearance. Furthermore, an ultraviolet absorber, an antioxidant, a lubricant and the like may be added.

The topcoat coating composition of the present invention can be manufactured as follows. First, the soft fluororesin (A) is dissolved in an organic solvent to produce a solution. As a suitable solvent, dimethylformamide or a mixed solvent of dimethylformamide and one or more of toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, cyclohexane and the like can be used. The resin concentration is usually used in the range of 5 to 20% by weight, and if it is 20% by weight or more, the stability of the solution becomes poor, which is not preferable. Furthermore, it is preferable to heat to 50 to 60 ° C. at the time of dissolution. Then, the solution of the soft fluororesin (A) and the solution of the copolymer (B) containing the quaternary ammonium salt obtained by polymerization as described above are added with a solvent, if necessary, and then the container It can be obtained by uniformly mixing in. Suitable concentrations and viscosities for use are 5-30% by weight and 20-1000 cps /
It is 30 ° C.

When a vinyl chloride resin molded article is overcoated with the above-mentioned overcoat coating composition, the overcoat coating composition is inferior in adhesion to the surface of the vinyl chloride resin formed article. It is necessary to subject the surface of the vinyl chloride resin molded product to a primer treatment. That is, according to the coating method of the present invention, first, the surface of a vinyl chloride resin molded article is treated with a primer composition, and the formed primer layer is dried, and then the soft fluororesin (A) and the fluoropolymer The above-mentioned composition for topcoat coating, which comprises the copolymer (B) containing a quaternary ammonium salt, may be further applied and dried.

The primer composition used in the present invention is one containing an acrylic polymer or copolymer. However, since the acrylic polymer or the copolymer alone has poor resistance to rubbing, it is more preferable to use a mixture thereof with a vinyl chloride resin. As the acrylic polymer or copolymer, an acrylate or methacrylate homopolymer or copolymer can be used. Examples of monomers that can be used in these homopolymers and copolymers include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, butyl acrylate. , Butyl methacrylate, lauryl acrylate, lauryl methacrylate, stearyl acrylate, stearyl methacrylate, hexyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, heptyl acrylate, heptyl methacrylate, and the like,
Similar esters having up to about 20 carbon atoms in the alkyl group can be used. Further, styrene, α-alkylstyrene, α-chlorostyrene, vinyltoluene, acrylonitrile, vinyl acetate and the like can be mentioned. In addition, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate,
Examples thereof include hydroxyl group-containing monomers such as 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, diethylene glycol monoacrylate and diethylene glycol monomethacrylate. Further, acrylic acid, α-chloroacrylic acid, methacrylic acid, itaconic acid, maleic anhydride, maleic acid, fumaric acid, crotonic acid, citraconic acid, mesaconic acid, etc., alone or in a mixture, or have at least one carboxyl group. Those functional derivatives can also be used, for example carboxyl group-containing monomers such as unsaturated polymerizable di- or polycarboxylic acid partial esters or amides.

Examples of vinyl chloride resins include polyvinyl chloride and vinyl chloride-vinyl acetate copolymers.
The mixing ratio of the acrylic polymer or copolymer and the vinyl chloride resin is preferably 100: 50 to 150 (weight ratio). When the mixing ratio of the vinyl chloride resin is lower than 50, the flexibility is lowered, and when it is higher than 150, the adhesion to the top coat is lowered, so the above range is preferable. The primer composition can be obtained by charging the acrylic polymer solution or copolymer solution, the vinyl chloride resin solution and the solvent into a container and uniformly mixing them in the container. Suitable concentrations and viscosities for use are 5-20% and 10%.
~ 2000 cps / 30 ° C.

The above-mentioned primer composition and the above-mentioned composition for overcoating are applied to a vinyl chloride resin molded article by a spray method, a brush coating method, a dipping method, a roll coater method,
It can be performed by a knife coating method or the like. The film thickness in that case is 1 to 10 μm for the primer layer and 1 to 20 for the overcoat layer.
It may be about μm.

The top coat composition of the present invention is a combination of the weather resistance and rubbing resistance of the soft fluororesin (A) and the antifouling property of the copolymer (B) having a quaternary ammonium salt in the molecule. Since it has, it forms a coating film excellent in weather resistance, resistance to rubbing, and antifouling property. Further, the coating film formed on the surface of the vinyl chloride resin according to the present invention can prevent the bleeding of the plasticizer in the vinyl chloride resin on the vinyl chloride resin surface and the primer layer having good adhesion to the overcoat coating layer. Since it has an overcoat layer, it prevents the surface of vinyl chloride resin molded products from being contaminated, and because it uses soft fluororesin, it retains weather resistance and kneading resistance, and because it is uncrosslinked It has the excellent property of good high-frequency adhesion. When the coated vinyl chloride resin molded product is subjected to high-frequency adhesion, it is desirable to apply the primer composition also to the back surface of the molded product. Thereby, a strong bond is obtained.

[0018]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples of the present invention, but the present invention is not limited thereto. Example 1 (Synthesis of Primer Composition) MEK850 was placed in a reaction vessel equipped with a cooling condenser, a thermometer and a stirrer.
After charging g and raising the temperature to 50 to 60 ° C., 150 g of vinyl chloride resin (Denka vinyl M-70, average degree of polymerization 700, manufactured by Denki Kagaku Kogyo Co., Ltd.) was added with stirring, and heated and dissolved for 1 to 2 hours. A 15% MEK solution of vinyl chloride resin having a viscosity of 80 cps / 30 ° C. was obtained. Separately, using the above device, M
After charging 700 g of EK and raising the temperature at 50 to 60 ° C., methyl methacrylate resin (Dianal Resin BR-8
(5, made by Mitsubishi Rayon Co., Ltd.) 300 g with stirring,
It was heated and dissolved for 1 to 2 hours to obtain a 30% methyl methacrylate resin MEK solution having a viscosity of 1000 cps / 30 ° C. Next, add 50 g of 15% MEK solution of vinyl chloride resin to the compounding container.
And 25 g of a 30% MEK solution of methyl methacrylate resin and 25 g of MEK were charged and mixed to obtain a viscosity of 50 cps /
A primer composition at 30 ° C. was obtained.

(Synthesis of Topcoat Coating Composition) Using the above reaction vessel, 800 g of DMF was charged and the temperature was raised to 60 to 70 ° C., after which a soft fluororesin (Sefraral Soft G-18 was used.
0, Central Glass Co., Ltd.) (200 g) was added with stirring, and the mixture was heated and dissolved for 2 to 3 hours to give a viscosity of 500 cps / 30.
A 20% soft fluororesin DMF solution at 0 ° C. was obtained. Separately, 650 g of DMF was charged into a 2-liter four-necked flask equipped with a nitrogen gas blowing port, a cooling condenser, and a thermometer, and the temperature was raised to 50 to 60 ° C., and then 2-methacryloyloxyethyltrimethylammonium chloride (DQ
-100, Kyoeisha Yushi Co., Ltd.) was added and dissolved with stirring. After that, methyl methacrylate (MM
A) (Mitsubishi Rayon Co., Ltd.) 339.5 g was added, nitrogen gas was blown in, AIBN (azobisisobutyronitrile, Otsuka Chemical Co., Ltd.) 0.3 g was added, and 90 to 100 ° C.
The reaction was completed by adding 0.30 g of AIBN twice every 2 hours for 2 hours. DMF750g was added, and MMA /
A 20% DMF solution of a quaternary ammonium halide group-containing acrylic resin with DQ-100 = 97/3 was obtained. The viscosity of the copolymer solution was 200 cps / 30 ° C. Next, add 50 g of the 20% DMF solution of the soft fluororesin to the compounding container.
And MMA / DQ-100 = 97/3 quaternary ammonium halide group-containing acrylic resin 20% DMF solution 25 g
Were mixed to obtain a top coat composition having a viscosity of 350 cps / 30 ° C.

Examples 2 to 12 In the method of Example 1, the resin component and amount in the primer composition were changed to the resin component and amount shown in Table 1, and blended, and the kind of soft fluororesin in the overcoat coating composition, A primer composition and a topcoat coating composition of the present invention were obtained under the same conditions as in Example 1, except that the type and amount of the quaternary ammonium halide group-containing acrylic resin were changed as shown in Table 1.

Comparative Examples 1 to 5 In the method of Example 1, except that the type of the soft fluororesin and the type and amount of the quaternary ammonium halide group-containing acrylic resin in the overcoat coating composition were changed as shown in Table 2. A primer composition and a top coat composition were obtained under the same conditions as in Example 1.

Comparative Example 6 (Synthesis of Primer Composition) A primer composition was obtained under the same conditions as in Example 1. (Synthesis of Topcoat Coating Composition) Using a reaction vessel similar to that in Example 1, 800 g of DMF was charged, the temperature was raised to 60 to 70 ° C., and then a soft fluororesin (Sefraral Soft G-18 was used.
0, Central Glass Co., Ltd.) (200 g) was added with stirring, and the mixture was heated and dissolved for 2 to 3 hours to give a viscosity of 500 cps / 30.
A 20% soft fluororesin DMF solution at 0 ° C. was obtained. Next, 50 g of the 20% DMF solution of the soft fluororesin and methylmethacrylate resin (Dianal Resin BR-
85, manufactured by Mitsubishi Rayon Co., Ltd.) 50 g of 20% MEK solution was mixed to obtain a composition for topcoat coating.

Comparative Examples 7 and 8 The procedure of Example 1 was repeated except that the amount of the soft fluororesin and the amount of the quaternary ammonium halide group-containing acrylic resin in the overcoat coating composition were changed as shown in Table 2. Under the same conditions as in Example 1, an overcoat coating composition was obtained. No primer composition was prepared. Comparative Example 9 Methyl Methacrylate Resin (Dianal Resin BR-
85, manufactured by Mitsubishi Rayon Co., Ltd.) 100 g of 20% MEK solution was prepared to obtain a top coat composition. No primer composition was prepared. Comparative Example 10 Using 100 g of the quaternary ammonium halide group-containing acrylic resin used in the method of Example 1, an overcoat coating composition was obtained. No primer composition was prepared.

(Preparation of test sample) Examples 1 to 1 were applied to a white soft vinyl chloride sheet containing 60 parts by weight of a plasticizer: dioctyl phthalate (DOP) per 100 parts by weight of resin.
2 and 1 in the primer compositions obtained in Comparative Examples 1 to 6.
A sheet was applied once with a 20-mesh gravure roll coater and heated and dried at 80 ° C. for 1 minute to prepare a sheet, on which the topcoat coating composition obtained in Examples 1 to 12 and Comparative Examples 1 to 6 was produced. In the same manner as in the case of the primer composition, the respective applicable primer coating layers were overcoated to obtain a test vinyl chloride sheet. Moreover, the white soft vinyl chloride sheet was directly coated with the composition for overcoating shown in Comparative Examples 7 to 10 in the same manner to obtain a test vinyl chloride sheet.

[0025]

[Table 1]

[0026]

[Table 2]

The test vinyl chloride sheet obtained as described above was tested and evaluated by the following method. The results are shown in Table 3 (Examples) and Table 4 (Comparative Examples).
Shown in. In addition, Table 4 also shows the case of no treatment (control).

Gloss of coating film: visually determined. The evaluation criteria are as follows. ◎… Excellent gloss ○… Good gloss △… Slightly inferior ×… Inferior gloss

Adhesion: 100 squares of 1 mm square were cut on the coating film with a knife, and the same portion was marked with 1 piece of cellophane adhesive tape.
Peeling was repeated 0 times and the remaining number was recorded. Soil compound stain recovery rate (Stain compound method) A test piece was cut into a width of 3 cm and a length of 4 cm and placed in a 300 ml glass bottle with a lid containing the following stain components. The dirt component is corrosive soil (commercially available
C. × 24 hr, dried, crushed 38.0% by weight, cement (commercial product 50 ° C. × 24 hr, dried, crushed) 17.0% by weight, kaolin (commercial product 50 ° C. × 24 hr, dried, crushed) 17. 0% by weight, silica gel (commercially available product at 100 ° C x
2 hr, dried, crushed, 200 mesh passed product) 17.0
% By weight, carbon black (diamond black H) 1.7
5% by weight, ferric oxide (commercial reagent first grade) 0.50% by weight, and mineral oil (mechanical oil / # 44, manufactured by Idemitsu Oil Co., Ltd.) 8.75% by weight were used. 80
After leaving it in the dryer at ℃ for 15 minutes, take out the glass bottle 2
I was shaken. This cycle was repeated 4 times. (Normal state) After treated by the above-mentioned stain compound method, lightly washed with water, Y value was measured with a color difference meter (CR-200, manufactured by Minolta Co., Ltd.), and the contamination recovery rate was calculated by the following formula. Pollution recovery rate (%) = (Y value before test / Y value before test) ×
100 The higher the numerical value of the pollution recovery rate, the better. (After rubbing resistance) Two test pieces were cut into a width of 3 cm and a length of 6 cm, the coated surfaces were overlapped with each other, a stroke of 3 cm and a load of 3 kg were set, and a rubbing compound test was performed after 1000 times of a softening test. The pollution recovery rate was calculated by the above method.

Oil-based magic stain, water-based magic stain: The line was drawn with a commercially available red water-based pen or red oil-based magic pen, allowed to stand at room temperature for 24 hours, wiped with ethanol-impregnated gauze, and visually judged. The evaluation criteria are as follows. ◎ ... No traces left ○ ... Slight traces left △ ... Slight traces left × ... Rare traces left Gloss of coating film after hot water test: 1 piece of test piece in warm water at 40 ° C
The gloss after immersion for a week was visually evaluated. The evaluation criteria are as follows. ◎… Excellent gloss ○… Good gloss △… Slightly inferior gloss ×… Inferior gloss Weather resistance test: Continuous irradiation using a sunshine weatherometer manufactured by Suga Test Instruments Co., Ltd., rain cycle 18 minutes / 120
Min, humidity 60%, black panel temperature 63 ° C 2000
A time-accelerated weathering test was performed, and the color difference ΔE after the test was measured with a color difference meter (CR-200, manufactured by Minolta).

[0031]

[Table 3]

[0032]

[Table 4]

[0033]

EFFECTS OF THE INVENTION Since the composition for topcoat coating and the coating method of the present invention have the above-mentioned constitution, a coating film having excellent adhesion is formed on the surface of a vinyl chloride resin molded article by the coating method of the present invention. And the formed coating can be
Prevents bleeding of plasticizers and prevents contamination by dust on the surface of vinyl chloride resin molded products and oil products, water-based inks, daily necessities such as food products, and excellent weather resistance, resistance to rubbing, and high-frequency adhesion. However, there are many places where there are industrial benefits.

Claims (2)

[Claims] 1. A soft fluororesin (A) comprising a fluororubber and a vinylidene fluoride resin as constituent components and a general formula (1): (In the formula, R ₁ , R ₂ and R ₃ each represent an alkyl group and Y represents a halogen atom.) And a quaternary ammonium halide group represented by the general formula (2): (In the formula, R ₄ represents a hydrogen atom or a methyl group) and a monomer (a) having an α, β-ethylenically unsaturated group and another α, β-ethylenically unsaturated monomer. A composition for topcoat coating of a vinyl chloride resin molded article that has been subjected to a primer treatment, characterized in that it comprises a copolymer (B) with the body (b). 2. A vinyl chloride resin molded article is treated with a primer composition comprising an acrylic polymer or copolymer or a mixture thereof with a vinyl chloride resin,
Then, a method for coating a vinyl chloride resin molded article, which comprises treating with the composition for overcoating according to claim 1.