JPH10216619A - Contamination preventing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent sticking of bills or scribbling by applying a primary coating material to form a coating film having a rough surface and then applying a clear coating material containing a moisture-cure polysiloxane resin as a vehicle component thereon to form an overcoat film. SOLUTION: After a primary coating material is used to form a film having a rough surface on the objective surface, a clear coating material containing a moisture-cure polysiloxane resin as a vehicle component is applied to form an overlay film so that even when a poster and the like is stuck to a building or the like, it can easily be peeled off without leaving its trace. As the primary coating material, a chief material for the multilayer finish coating such as a synthetic resin emulsion film, an elastic material such as a substrate controlling coating material and a thick film type epoxy resin coating material are exemplified. Preferably, an elastic water-based coating material for an elastic base coat which contains a carbonyl group-contg. copolymer emulsion and pigments and 30 to 70vol.% concn. of the pigments in the coating material and 30 to 150% elongation of the formed film at 20 deg.C is preferably used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing sticking or graffiti on a building or the like, and particularly to a method for preventing contamination which can be easily peeled off without leaving a trace even if the sticking is applied.

[0002]

[Prior art and its problems] Electric poles, lampposts, fences, pedestrian bridges,
Advertisements, advertising leaflets, and other stickers and graffiti on the concrete and painted surfaces of buildings such as walls, piers, tunnels, and gates not only impair the appearance but also remove and remove them. A great deal of labor and cost was required. Therefore, conventionally, a bead-containing paint has been applied to the surface of these buildings to form an uneven coating surface so that the sticking paper is hard to stick, and a silicone oil or the like is used to prevent graffiti from sticking. Apply paint with wax added,
It has been proposed to form a pollution control coating by applying a resin paint (for example, Japanese Patent Publication No. 53-1991).
No. 4, JP-B-62-24465, JP-B-57-373
89, JP-A-6-182290, etc.).

[0003] However, in the case of the bead-containing coating film, the unevenness of the surface may be sharpened depending on the shape of the object to be coated and the coating method, and may be disliked by the owner. When graffiti is applied repeatedly, the grime is repeatedly wiped off with a thinner or rubbed with a brush, and silicon oil and the like on the surface gradually disappears, and the graffiti removal effect is likely to be reduced. On the other hand, when a silicone resin paint is applied, it cannot be used as it is on an existing painted surface, and the undercoat or intermediate coat dedicated to the paint is required, so that the work is complicated and the cost is high. Is usually a two-pack type and has a problem in workability.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, by forming a specific clear coating film on an uneven coating film made of an undercoat paint, it is possible to form a paper or graffiti. The present inventors have found that a stain prevention coating film that can be effectively prevented can be formed, and the present invention has been achieved.

That is, according to the present invention, an uneven coating film is formed on a surface to be coated by using an undercoating material, and then a clear film containing a moisture-curable polysiloxane resin as a vehicle component thereon.
An object of the present invention is to provide a method for preventing contamination, which comprises forming a top coat using a paint.

Hereinafter, the present invention will be described in detail.

[0007] The undercoat paint used in the present invention is a paint for forming an uneven coating film on the surface to be coated, and is a multi-layer finish of a conventionally known synthetic resin emulsion, cement, polymer-cement or the like. Elastic materials such as a main material for use or a base adjustment coating material, and a thick-film type epoxy resin-based paint. The undercoat paint contains, in particular, a carbonyl group-containing copolymer emulsion and a pigment, the pigment has a pigment volume concentration of 30 to 70%, and the formed film has an elongation of 20 ° C.
A water-based paint for an elastic base having an atmosphere of 30 to 150% is preferred.

The carbonyl group-containing copolymer emulsion used in the elastic base water-based coating composition comprises (a) 0.1 to 30% by weight of a carbonyl group-containing unsaturated monomer, and (b) a water-soluble unsaturated monomer. A copolymer obtained by emulsion-polymerizing a monomer mixture containing 0 to 10% by weight of a monomer and (c) 60 to 99.9% by weight of another unsaturated monomer in the presence of an emulsifier. A coalesced emulsion can be suitably used.

As the monomer (a), for example, acrolein, diacetone acrylamide, diacetone methacrylamide, formyl styrene, vinyl alkyl ketone having 4 to 7 carbon atoms (for example, vinyl methyl ketone, vinyl ethyl ketone, Vinyl butyl ketone) and the like. Of these, diacetone acrylamide and diacetone methacrylamide are particularly preferred.

Examples of the monomer (b) include (meth) acrylic acid, maleic acid, crotonic acid, β-carboxyethyl acrylate, 2-acrylamido-2-methylpropanesulfonic acid, allylsulfonic acid, and styrene. Sulfonate sodium salt, sulfoethyl methacrylate and its sodium salt and ammonium salt; (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, dimethylaminoethyl (meth) acrylate, glycidyl (meth) acrylate Adducts with amines; and (meth) acrylates having a polyoxyethylene chain.

Examples of the monomer (c) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and butyl (meth) acrylate.
(Meth) acrylic acid such as 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, lauryl (meth) acrylate and isobornyl (meth) acrylate having 1 to 24 carbon atoms Alkyl or cycloalkyl esters; hydroxyalkyl esters of (meth) acrylic acid having 2 to 8 carbon atoms, such as 2-hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; styrene, vinyltoluene, etc. Vinyl aromatic compounds; N-vinylpyrrolidone, ethylene, butadiene, chloroprene, vinyl propionate, vinyl acetate, (meth) acrylonitrile, and the like, which are used as appropriate according to desired performance.

The water-based paint for an elastic base may or may not contain a cross-linking agent component capable of cross-linking with the carbonyl group-containing copolymer emulsion. As a crosslinking agent component,
A hydrazide compound having at least two hydrazide groups in one molecule can be used, and examples thereof include dihydrazides of dicarboxylic acids such as adipic dihydrazide and succinic dihydrazide. Further, as a vehicle component of the water-based paint for an elastic base, the carbonyl group-containing copolymer emulsion may be further used as well as a known emulsion conventionally used in the field of paints, for example, a vinyl acetate emulsion, an acrylic resin emulsion, a vinyl acetate-acryl emulsion. Alternatively, ethylene-vinegar biemulsion or the like may be added in such an amount that the proportion of the solid content in the total vehicle components is 50% by weight or less.

The pigment used in the above-mentioned water-based paint for elastic base includes, for example, coloring pigments such as titanium oxide, carbon black and red iron oxide, calcium carbonate, talc, mica, clay, diatomaceous earth and silica sand. And fillers such as pearlite, aggregates, etc., which can be appropriately selected and used.

In the water-based paint for an elastic base, the pigment has a pigment volume concentration (hereinafter sometimes abbreviated as "PVC") in the paint of 30 to 70%, preferably 40 to 60%.
It is blended so that Here, "Pigment volume concentration (PV
"C)" is the volume ratio of the pigment to the solid content of the mixture of the resin and the pigment. If the PVC content is less than 30%, the resulting coating film has a poor feeling of stickiness, and the base adjustment ability and the formation of irregularities are reduced. On the other hand, if the PVC content exceeds 70%, the denseness of the obtained coating film is reduced, and It is not preferable to apply a top coat over the coating film because unevenness in suction of the top coating material is liable to occur and a good finished appearance is not obtained, and the physical properties of the coating film itself are deteriorated.

The elongation of the coating film formed by the water-based paint for elastic base is 30 to 150%, preferably 40 to 140% in a 20 ° C. atmosphere. Here, the elongation percentage of the coating film is measured using a universal tensile tester equipped with a thermostat (Autograph AG2 manufactured by Shimadzu Corporation).
000B type), at 20 ° C, tensile speed 200m
It is a value measured at m / min, and the sample used for the measurement was prepared according to JIS-A-6909.
If the elongation percentage is less than 30%, the resulting coating film cannot sufficiently follow cracks on the surface to be coated, while if it exceeds 150%, the top coating film may not be cracked depending on the type of top coating material applied over the coating film. Is sometimes not preferred.

The above-mentioned water-based paint for an elastic base may further contain a surfactant, a dispersant, an antifoaming agent, a thickener, a film-forming aid, a preservative, an antifreezing agent, an organic solvent, etc., if necessary. Paint additives can be included.

The clear coating material used in the present invention comprises, as a vehicle component, a moisture-curable polysiloxane resin which can be hydrolyzed with moisture in the air and crosslinked and cured by a condensation reaction such as deoximation or alcohol removal. It contains.

The moisture-curable polysiloxane resin includes a polyfunctional resin having a hydrolyzable group such as a ketoxime group, an alkoxy group, or an acetoxy group in an organopolysiloxane in which an organic group, which is mainly a methyl group, is directly bonded to Si. Examples include those containing a silane compound and a curing catalyst such as octylates such as zinc, iron, cobalt and tin, naphthenates and peroxides.

A silane coupling agent or the like may be added to the above resin, if necessary, in order to improve the adhesion to the surface to be coated.

As the organic solvent for diluting the resin, aromatic hydrocarbon solvents such as toluene and xylene, and aliphatic hydrocarbon solvents such as hexane and heptane can be used.

Specific examples of the moisture-curable polysiloxane resin include KE441, KE445, KE471, K
E44, KE47, KE45S, KE4895, KE4
525, KE4805 (all manufactured by Shin-Etsu Chemical Co., Ltd., trade name), SR2404, SR2405, SR2406,
SR2410, SR2411, SR2306, SR23
10, SR2316, SE5060, SE5070 (all manufactured by Toray Downconing Silicone Co., Ltd., trade names) and the like.

The above clear coating composition has the following general formula from the viewpoint of preventing contamination.

[0023]

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(Wherein R is the same or different and represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), and preferably contains an organosilicate and / or a condensate thereof. Specific examples of the organosilicate include:
For example, tetramethoxysilane, tetraethoxysilane,
Tetrapropoxysilane, dimethoxydiethoxysilane and the like are mentioned, and the condensate of organosilicate is a branched or straight-chain condensate of organosilicates represented by the above general formula. Commercially available products such as ethyl silicate 40, ethyl silicate 48, and methyl silicate 51 (each manufactured by Corcote) can be used. These can be used alone or in combination of two or more. The amount of the organosilicate and / or the condensate thereof is suitably in the range of about 1 to 40 parts by weight per 100 parts by weight of the resin solid content in the coating material.

If necessary, the clear coating composition may further contain silicone oil or waxes such as chlorinated paraffin, solid paraffin, or liquid paraffin, in an amount of about 10 parts by weight or less per 100 parts by weight of the resin solid content in the coating composition. , And the sticking prevention function is improved.

The clear paint may further contain pigments such as extenders and color pigments; paint additives such as plasticizers, anti-sagging agents and coating surface adjusters according to the required coating properties. Can be blended.

In the method of the present invention, the undercoating obtained as described above is applied so as to form a concavo-convex coating film after the surface to be coated is directly or undercoated, and then the clear coating is applied. is there.

The surface to be coated can be applied without particular limitation, such as a ground surface of a building or the like, or a painted surface. Examples of the ground surface include a concrete surface, a mortar surface, a slate plate, a PC plate, and an A plate.
LC plate, concrete block surface, wood, stone, plastic, metal, etc., and the coating surface is, for example, an acrylic urethane resin-based material painted on these bare surfaces.
Old coating films such as polyurethane resin, fluorine resin, and silicone resin can be used.

The undercoat is applied over the entire surface to be coated by a coating method using a known coating device such as a roller, an air spray, an airless spray, a ricin gun, a universal gun, and a brush. 0.5-5m in height
m, and a width of 1 to 10 mm of convex portions is distributed, such as a yuzu skin pattern). The coating amount is 0.2-1.5k
g / m ² , preferably 0.3 to 1.3 kg / m ² .

The above-mentioned clear paint is applied on the uneven coating film formed as described above. Before coloring the clear paint, it is necessary to apply an aqueous or organic paint, if necessary, from the coloration of the finished surface. A solvent-based enamel paint can be applied on the uneven coating film. For example, an acrylic resin, an acrylic urethane resin, a polyurethane resin, a fluororesin, or a silicone acrylic resin-based overcoat can be used.

The above-mentioned enamel paint and clear paint can be applied by a usual coating method such as roller, brush, spray, etc., and the enamel paint has a dry film thickness of 20 to 60 μm. It is appropriate to apply the coating so as to have a range of 10 to 30 μm.

[0032]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples.

Production of Copolymer Emulsion 312 parts by weight of deionized water, Newcol 707SF (manufactured by Nippon Emulsifier Co., anionic surfactant having a polyoxyethylene chain, nonvolatile content of 30%) was placed in a two-liter four-necked flask. 0.3 parts by weight, and after nitrogen replacement, at 80 ° C.
Kept. 0.7 parts by weight of ammonium persulfate was added thereto, and 15 minutes after the addition, a pre-emulsion obtained by emulsifying the following composition was added dropwise over 3 hours.

Deionized water 338 parts by weight Diacetone acrylamide 32 parts by weight Acrylic acid 3.2 parts by weight Styrene 97 parts by weight Methyl methacrylate 260 parts by weight 2-ethylhexyl acrylate 100 parts by weight n-butyl acrylate 150 Parts by weight Newcol 707SF 62 parts by weight Ammonium persulfate 1.2 parts by weight After 30 minutes from the end of the dropping, 7.7 parts by weight of a solution obtained by dissolving 0.7 parts by weight of ammonium persulfate in 7 parts by weight of deionized water was used. The dropping was started, and the dropping was completed over 30 minutes. After keeping this at 80 ° C. for another 2 hours,
The temperature was lowered to 0 ° C. Then, the pH was adjusted to 8 to 9 with aqueous ammonia to obtain a copolymer emulsion having a solid content of 51% by weight. The pH of the emulsion was 8.2.

Preparation of Undercoat Paint The components shown in Table 1 were blended with the copolymer emulsion obtained in the above Production Example, and the mixture was stirred and mixed to obtain an undercoat paint. Table 1 shows the characteristic values of both paints. In addition, "Epomarin SHB" (manufactured by Kansai Paint Co., Ltd., thick film type epoxy resin paint) was used as the undercoat paint. Note that (Note 1) to (Note 5) in Table 1 are as follows.

(Note 1) Extender: calcium carbonate having a specific gravity of 2.7 (Note 2) Thickener: 2.5% hydroxyethyl cellulose (Note 3) Defoamer: “SN Deformer-A63” (Manufactured by San Nopco) (Note 4) Dispersant: "Nopco Santo K" (manufactured by San Nopco) (Note 5) Elongation (%) of formed coating film: JIS A 690
A test piece was prepared in accordance with No. 9 and the elongation percentage of the dried coating film was measured using a tensile tester Autograph AG2000B type (manufactured by Shimadzu Corporation).
Was measured in a 20 ° C. atmosphere at a tensile speed of 200 mm / min.

[0037]

[Table 1]

Preparation of Clear Paints Clear paints A to J were prepared according to the formulations shown in Table 2. In the table, (Note 6) to (Note 13) are as follows.

(Note 6) KE445, KE471, KE4
41: moisture-curable polysiloxane resin manufactured by Shin-Etsu Chemical Co., Ltd. (Note 7) Hitaloid 3083: manufactured by Hitachi Chemical Co., Ltd., acrylic polyol resin solution, solid content 60% (Note 8) Duranate 24A: manufactured by Asahi Kasei Corporation Hexamethylene diisocyanate, solid content 90% (Note 9) SH28PA: manufactured by Toray Dow Corning Silicone Co., Ltd., silicon resin (Note 10) YC-3835: Kanegafuchi Chemical Industry Co., Ltd., acrylic silicon Resin liquid, solid content 51% (Note 11) ZT-118Z: Kanegafuchi Chemical Co., Ltd., curing catalyst, solid content 16% (Note 12) KP358: Shin-Etsu Chemical Co., Ltd., silicone oil (Note 13) ) Ethyl silicate 40: Organosilicate condensate, manufactured by Corcot Co.

[0040]

[Table 2]

Examples and Comparative Examples A mortar board (JIS A5304, 300 × 150 × 60 mm) cured at 20 ° C. and 75% RH for 10 days or more was coated with “KC Epoprimer” (Kansai Paint Co., Ltd., epoxy resin clearer). - La -) the filtrate of the coating amount 80 g / m ² -
A plate to be coated and dried at room temperature for one day was used as a coated plate.

The undercoat paint shown in Table 3 was selected for the plate to be coated, and the sand bone roller was coated at an application amount of about 800 to 1,000 g / m ^2.
Painted and dried at room temperature for 1 day. The obtained undercoating film surface had a height of 0.5 to 1.5 mm and a finish of a yuzu skin pattern in which convex portions having a width of 1 to 2 mm were distributed. Next, about 200 g / m ² of “Rethane 6000 White” (manufactured by Kansai Paint Co., Ltd., polyurethane resin-based paint) was applied on the undercoating film.
And then dried at room temperature for one day.

Further, the clear paints shown in Table 3 were further selected and brush-coated with a coating amount of about 100 to 150 g / m ² and dried at room temperature for 1 day to obtain a coated plate. A performance test was performed on each of the obtained coated plates. In addition, for each coated plate, one reserved coated plate was prepared and stored indoors. Table 3 shows the results.

The test methods in Table 3 are as follows.

Test method (* 1) Adhesion: 9 cuts of 5 × 5 mm were made on the coating film of the test coated plate to reach the bare ground, and a cellophane adhesive tape was stuck on the cut. The state of the coating film after peeling was evaluated.

○: No peeling was observed at all Δ: Slight peeling was observed ×: Remarkable peeling was observed (* 2) Graffiti removal property: “Aeron A” (manufactured by Campe Hapio Co., Ltd. Acrylic lacquer spray)
I doodle with. After leaving it for 1 day and 10 days, it was examined whether it could be easily removed by the following removal method and the state of the coated surface after removal.

(Removal method) a. Wipe off with thinner in gauze b. Remove by attaching / detaching gum tape. C. Wash with water while scrubbing (removability evaluation criteria) ○: Complete removal △: Some graffiti remains ×: Graffiti remains fairly (painted surface evaluation criteria) ○: Good △: Slight removal marks remain ×: Removal marks are considerable Remaining (* 3) Paste removal property: After imitation paper is pasted on the coated surface of the test coated plate with synthetic glue, rubbed on it many times, left for 7 days, peeled off the imitation paper by hand, and peeled off Was observed.

◎: No trace of peeling easily recognized ○: No trace of adhesive paper observed △: Partially attached adhesive paper ×: Adhered adhesive paper considerably (* 4) Outdoor exposure test: Test coated plate After outdoor exposure for 6 months and 12 months, the appearance of the coating film was visually observed. The stain on the paint film was compared with a copy coated for preservation indoors and the degree of the stain was visually evaluated.

(Appearance of coating film) ：: Good 若干: Slightly glossy △: Slightly cracked and cracked (degree of dirt) ：: Almost the same as the spare coating plate and almost unstained ：: Smoke stain slightly adhered Δ: Adhesion of soot and dirt is conspicuous X: Dirt is adhering to the entire surface

[0050]

According to the present invention, a specific clear coating film is formed on an uneven coating film of an undercoat paint,
It is possible to form a pollution-preventing coating film that effectively prevents sticking and graffiti, and that can easily be peeled off without leaving a trace even if the sticking paper is stuck.

[0051]

[Table 3]

[0052]

[Table 4]

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masayoshi Saito 3-12-1, Minamirokugo, Ota-ku, Tokyo Kansai Paint Co., Ltd. (72) Inventor Toshiyuki Satake 3-1-1, Minamirokugo, Ota-ku, Tokyo No. Kansai Paint Co., Ltd. (72) Inventor Shinji Iida 3-12-1, Minamirokugo, Ota-ku, Tokyo Kansai Paint Co., Ltd.

Claims (3)

[Claims] An uneven coating film is formed on a surface to be coated by using an undercoating material, and a topcoating film is formed thereon by using a clear coating material containing a moisture-curable polysiloxane resin as a vehicle component. Contamination prevention method. 2. The undercoat paint contains a carbonyl group-containing copolymer emulsion and a pigment, the pigment has a pigment volume concentration of 30 to 70%, and the formed coating film has an elongation of 2%.
The method for preventing contamination according to claim 1, which is a water-based paint for an elastic base which has a content of 30 to 150% in a 0 ° C atmosphere. 3. The method according to claim 1, wherein the clear coating composition contains an organosilicate and / or a condensate thereof.