JP2017141340A - Primer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a primer composition which can easily peel a surface sheet such as a decorative sheet immediately after the surface sheet has been stuck to a surface of a base material through an adhesive, and can strongly bond and integrate the decorative sheet to the surface of the base material through the adhesive with the lapse of time.SOLUTION: A primer composition contains an organic solvent (A) capable of dissolving a polyvinyl chloride resin, a polymer (B) capable of dissolved in the organic solvent, and a surface conditioner (C) that controls a surface tension of a dry coated film.SELECTED DRAWING: None

Description

  The present invention relates to a primer composition.

  Conventionally, design properties are imparted by bonding a decorative sheet to a surface of a base material such as furniture, an exterior material, and an interior material using an adhesive.

  Conventionally, an adhesive containing an organic solvent and a moisture-curable hot melt adhesive have been used as an adhesive used for adhering the decorative sheet to the substrate surface. Moisture curable hot melt adhesives are often used because they do not contain volatile organic compounds (VOC) that cause sick house syndrome, are excellent in work hygiene, and can suppress environmental pollution.

  In addition, since the base material has an excellent heat insulating effect and an energy saving effect, synthetic resins such as polyvinyl chloride resins have been developed.

  However, synthetic resin base materials tend to have poor adhesion, and when a decorative sheet is adhered to the surface of the base material, a pretreatment such as applying a primer composition to the surface of the base material may be performed. Many.

  As such a primer composition, Patent Document 1 discloses that 0.5 to 10 parts by weight of a polyisocyanate compound and 0.01 to 1.0 to 1,4-butanediol with respect to 1 part by weight of a silicone-modified acrylic resin. A primer composition to which parts by weight have been added is disclosed.

Japanese Patent Laid-Open No. 11-181351

  On the other hand, some trouble may occur during the process of attaching the decorative sheet to the surface of the base material via an adhesive. In such a case, the decorative sheet needs to be peeled off from the surface of the base material.

  However, since the primer composition is excellent in initial adhesiveness with the adhesive, when the decorative sheet is peeled off from the surface of the base material, the solidified adhesive remains on the surface of the base material, and this residual adhesive If the substrate is not removed with a solvent or the like, there is a problem that the substrate cannot be reused, which causes another problem that the defect rate increases and the lead time deteriorates.

  Further, the decorative sheet bonded and integrated with the surface of the base material is required not to be easily peeled off during subsequent use, and is required during the process of bonding and integrating the decorative sheet to the surface of the base material. Are required to conflict.

  In the present invention, the surface sheet can be easily peeled off from the substrate surface immediately after the surface sheet such as a decorative sheet is bonded to the surface of the substrate via an adhesive, and the surface sheet is bonded over time. Provided is a primer composition that can be firmly bonded and integrated with the surface of a substrate via an agent.

  The present invention includes an organic solvent (A) that can dissolve a polyvinyl chloride resin, a polymer (B) that can be dissolved in the organic solvent, and a surface conditioner (C) that adjusts the surface tension of the dried coating film. It is characterized by containing.

  Since the present invention has the configuration as described above, the surface sheet is easily peeled off from the surface of the substrate immediately after the surface sheet is bonded onto the substrate containing the polyvinyl chloride resin. The bonding state of the sheet can be easily corrected (removability).

  Furthermore, in the present invention, after the surface sheet is bonded to the surface of the base material containing the polyvinyl chloride resin, the surface sheet can be firmly bonded and integrated on the surface of the base material after curing and curing of the adhesive. (Adhesiveness).

  The primer composition of the present invention includes an organic solvent (A) capable of dissolving a polyvinyl chloride resin, a polymer (B) soluble in the organic solvent, and a surface conditioner for adjusting the surface tension of the dried coating film. (C).

[Organic solvent that can dissolve polyvinyl chloride resin (A)]
The primer composition contains an organic solvent (A) that can dissolve the polyvinyl chloride resin. This is because the primer composition exhibits adhesion as a dope cement to a base material containing a polyvinyl chloride resin. Therefore, when the primer composition is applied to the substrate surface, the organic solvent (A) in the primer composition dissolves the polyvinyl chloride resin constituting the surface of the substrate, and the organic solvent (A) The dried coating film formed by the polymer (B), which will be described later, dissolved in the substrate is integrated with the substrate surface.

  The organic solvent (A) capable of dissolving the polyvinyl chloride resin is not particularly limited as long as it can dissolve the polyvinyl chloride resin, but ketone or ether is preferable. Examples of the ketone include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diisobutyl ketone, isophorone, acetophenone, and benzophenone. Methyl ethyl ketone and acetone are preferable, and methyl ethyl ketone is more preferable. Examples of the ether include tetrahydrofuran, diethyl ether, dioxane, ethyl cellosolve, butyl cellosolve, and the like, and tetrahydrofuran is preferable. In addition, an organic solvent (A) may be used independently or 2 or more types may be used together. When the organic solvent is a mixture of a plurality of types of organic solvents, it is only necessary that one of the plurality of types of organic solvents can dissolve the polyvinyl chloride resin.

  The polyvinyl chloride resin refers to a synthetic resin containing vinyl chloride as a monomer component. Examples of the polyvinyl chloride resin include, for example, a polyvinyl chloride homopolymer, a copolymer of a vinyl chloride monomer and a monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer, and vinyl chloride as a monomer. Examples thereof include a graft copolymer obtained by graft-polymerizing vinyl chloride to a polymer not contained as a component (for example, a polyolefin resin).

  Examples of the monomer having an unsaturated bond copolymerizable with vinyl chloride monomer include α-olefins such as ethylene, propylene, and butylene, vinyl esters such as vinyl acetate and vinyl propionate, butyl vinyl ether, cetyl vinyl ether, and the like. Vinyl ethers, (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate and butyl acrylate, aromatic vinyls such as styrene and α-methylstyrene; N-phenylmaleimide, N-cyclohexylmaleimide and the like N-substituted maleimides and the like.

(Polymer soluble in organic solvent)
The primer composition contains a polymer (B) that is soluble in the organic solvent (A). Whether the polymer (B) can be dissolved in the organic solvent (A) is determined by the following method. 13.5 parts by mass of the organic solvent (A) and 1.5 parts by mass of the polymer (B) were supplied to a glass beaker and stirred at 25 ° C. at a rotation speed of 150 rpm for 6 hours, and then at 25 ° C. for 30 minutes. Leave still. It is visually observed whether or not a precipitate is present in the organic solvent (A). If no precipitate is present, it is determined that the polymer (B) can be dissolved in the organic solvent (A).

  As the polymer (B), in the state of constituting the primer composition, it dissolves in the organic solvent (A) to form a uniform phase, and the dried coating film after the removal of the organic solvent (A) For example, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, acrylic resin (acrylic acid-styrene copolymer, etc.), polyvinyl alcohol, epoxy resin, urethane, etc. Resin, alkyd resin, polyester resin, ethylene-vinyl acetate copolymer, phenol resin, amino resin, fluororesin, silicone resin, petroleum resin, etc., vinyl chloride-vinyl acetate copolymer, acrylic resin are preferred, Since the removability of the primer composition is improved, it is preferable to use a vinyl chloride-vinyl acetate copolymer and an acrylic resin in combination. Arbitrariness. In addition, a polymer (B) may be used independently or 2 or more types may be used together. When the polymer (B) is a mixture of a plurality of types of polymers, it is sufficient that at least one of the polymers can be dissolved in the organic solvent (A).

  The polymer (B) is at least one selected from the group consisting of polyvinyl chloride, a vinyl chloride-vinyl acetate copolymer and an acrylic resin because the primer composition is excellent in removability and adhesiveness. It is preferable that the polymer is contained, polyvinyl chloride and vinyl chloride-vinyl acetate copolymer are more preferable, and vinyl chloride-vinyl acetate copolymer is particularly preferable. The polymer (B) preferably contains a vinyl chloride-vinyl acetate copolymer and an acrylic resin because the removability of the primer composition is improved.

  The vinyl chloride-vinyl acetate copolymer is commercially available from Nisshin Chemical Industry under the trade names “Solvine CN” and “Solvine CH”, for example.

  Acrylic resin is an acrylic monomer such as (meth) acrylate or (meth) acrylic acid as the main component (50% by mass or more), and can be copolymerized with an acrylic monomer as required. It is a polymer of a monomer composition containing a monomer. Examples of (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and the like. Examples of the monomer copolymerizable with the acrylic monomer include styrene. In the present invention, (meth) acrylate means acrylate or methacrylate. (Meth) acrylic acid means acrylic acid or methacrylic acid.

  The content of the polymer (B) in the primer composition (when the polymer (B) contains two or more kinds of polymers, the total content of the polymers) is the organic solvent (A) (organic When the solvent (A) contains two or more kinds of organic solvents, 0.1 to 20 parts by mass is preferable with respect to 100 parts by mass, and 1 to 10 parts by mass is more preferable. . Adhesiveness of a primer composition improves that content of a polymer (B) is 0.1 mass part or more. When the content of the polymer (B) is 20 parts by mass or less, the primer composition has an appropriate viscosity, and the primer composition has excellent coatability.

[Surface conditioner (C) that adjusts the surface tension of the dried coating film]
The primer composition contains a surface conditioner (C) in order to adjust the surface tension of the dried coating film formed after the removal of the organic solvent (A).

  The surface conditioner (C) adjusts the surface tension (wetability) of the dried coating film formed after removing the organic solvent (A) from the primer composition, so that the surface conditioning agent (C) is between the dried coating film and the adhesive. The balance between the initial adhesiveness and the adhesiveness between the cured product after curing and curing of the adhesive and the dried coating film is achieved to achieve both re-peelability and adhesiveness of the primer composition.

  The surface conditioner (C) is not particularly limited as long as the surface tension of the dried coating film of the primer composition can be adjusted. For example, a fluorine-based surface conditioner, a silicone-based surface conditioner, and an acrylic surface conditioner Since the surface tension can be adjusted with a small amount of addition, a fluorine-based surface conditioner and a silicone-based surface conditioner are preferable, and a fluorine-based surface conditioner is more preferable. In addition, a surface conditioning agent (C) may be used independently, or 2 or more types may be used together.

  Examples of the fluorine-based surface conditioner include perfluoroalkyl group-containing oligomers. Examples of the fluorine-based surface conditioner include trade names “BYK-340” from BYK Chemie, trade names “F-474” and “F-479” from Dainippon Ink Industries, and trade names “Surflon” from AGC Seimi Chemical. S-111N, Surflon S-113, Surflon S-121, Surflon S-131, Surflon S-132, Surflon S-141, Surflon S-381, Surflon S -383 "," Surflon S-651 "and" Surflon S-243 "can be used.

  Examples of the silicone-based surface conditioner include organopolysiloxanes such as dimethylpolysiloxane and modified silicones obtained by modifying organopolysiloxane. Specific examples of the modified silicone include alkyl-modified polysiloxane, phenyl-modified polysiloxane, and polyether-modified polysiloxane.

  Specifically, as the silicone-based surface conditioner, for example, dimethylpolysiloxane, methylphenylpolysiloxane, polyether-modified dimethylpolysiloxane, polyester-modified dimethylpolysiloxane, polyester-modified dimethylpolysiloxane, polymethylalkylsiloxane, polyester-modified Examples include methylalkylpolysiloxane, aralkyl-modified methylalkylpolysiloxane, polyether-modified acrylic group-containing dimethylpolysiloxane, and polyester-modified (meth) acryloyl group-containing dimethylpolysiloxane.

  Silicone surface conditioners are, for example, trade names “DC11PA”, “ST80PA”, “DC3074”, “DC3037” and “SR2402” from Toray Dow Corning, trade names “KP-321” from Shin-Etsu Chemical Co., Ltd. What is marketed by "KP-324", "KP-327", "KR-9218", and "X-40-9220" can be used.

  As an acrylic surface conditioner, for example, an alkyl ester monomer of (meth) acrylic acid such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate is used as a raw material. Examples thereof include acrylic polymers having a weight average molecular weight of 300 to 50,000. Also included are silicon-modified acrylic polymers. The silicon-modified acrylic resin can be obtained, for example, by copolymerizing an acrylate monomer containing silicon (Si) and an alkyl (meth) acrylate.

  Examples of the acrylic surface conditioner include trade names “BYK-350”, “BYK-352”, “BYK-354”, “BYK-355”, “BYK-358N”, “BYK-” from Big Chemie Japan. "361N" and "BYK-392", trade names "DISPARLON LF-1980", "DISPARLON LF-1982", "DISPARLON LF-1983", "DISPARLON LF-1984", "DISPARLON LF-1985" What is marketed by "DISPARLON NSH-8430HF" can be used.

  The content of the surface conditioner (C) in the primer composition (when the surface conditioner (C) contains two or more kinds of surface conditioners, the total content of the surface conditioners) is the organic solvent ( A) 0.01-10 mass parts is preferable with respect to 100 mass parts, and 0.1-3 mass parts is more preferable. When the content of the surface modifier (C) is within the above range, the primer composition can achieve both removability and adhesiveness.

[Other ingredients]
The primer composition may contain additives such as an antioxidant, an ultraviolet absorber, and a filler as long as the physical properties are not impaired.

〔Antioxidant〕
The antioxidant is not particularly limited, and examples thereof include 2,6-di-t-butyl-4-methylphenol and n-octadecyl-3- (4′-hydroxy-3 ′, 5′-di-t-). Butylphenyl) propionate, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-ethyl-6-tert-butylphenol), 2,4-bis (octylthiomethyl) ) -O-cresol, 2-t-butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2,4-di-t-amyl-6 [1- (3,5-di-t-amyl-2-hydroxyphenyl) ethyl] phenyl acrylate, 2- [1- (2-hydroxy-3,5-di-tert-pentylphenyl)] acrylate, te Lax [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] hindered phenolic antioxidants such as methane, dilauryl thiodipropionate, lauryl stearyl thiodipropionate, penta Sulfur-based antioxidants such as erythritol tetrakis (3-laurylthiopropionate), phosphorus-based antioxidants such as tris (nonylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite, etc. Is mentioned. In addition, an antioxidant may be used independently or 2 or more types may be used together.

(UV absorber)
Examples of the ultraviolet absorber include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-t-butylphenyl) benzotriazole, 2- (2 ′ -Hydroxy-3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole and other benzotriazole ultraviolet absorbers; 2-hydroxy-4-methoxybenzophenone and other benzophenone ultraviolet absorbers; salicylic acid ester Examples include ultraviolet absorbers, cyanoacrylate ultraviolet absorbers; hindered amine light stabilizers. An ultraviolet absorber may be used individually by 1 type, and may use 2 or more types together.

(filler)
Examples of the filler include mica, calcium carbonate, kaolin, talc, titanium oxide, diatomaceous earth, urea resin, styrene beads, calcined clay and starch.

  The procedure for using the primer composition will be described. The primer composition is preferably used when a surface sheet is bonded and integrated to the surface of a substrate containing a polyvinyl chloride resin via an adhesive.

  Specifically, the primer composition is applied to the surface of a base material containing a polyvinyl chloride resin in a general manner, and dried at room temperature or by heating to remove the organic solvent (A), thereby removing the surface of the base material. Integrate the dry film into It is formed in a state where the dry coating film of the primer composition is firmly integrated on the surface of the substrate.

  Thereafter, after applying an adhesive to the back surface of the top sheet, the top sheet is bonded to the surface of the substrate using a lapping machine or the like. At this time, since the dry coating film of the primer composition has an appropriate surface tension (wetting property), if the surface sheet is just pasted to the surface of the substrate, the adhesive residue of the adhesive is removed. The surface sheet can be peeled off smoothly from the surface of the base material with almost no occurrence, and the surface sheet can be bonded again to the surface of the base material, thereby reducing the defect rate and the lead time. .

  And after curing and curing the adhesive, the dried coating film of the primer composition is firmly integrated with the adhesive, and the surface sheet is firmly bonded to the surface of the base material, which is excellent for a long period of time. Maintain the decorative effect.

  As the surface sheet, a conventionally known decorative sheet or the like is used, and examples thereof include a polyvinyl chloride resin sheet and a polyolefin resin sheet.

  The adhesive only needs to be able to bond and integrate the surface sheet to the surface of the substrate, and examples thereof include a moisture-curable urethane hot melt adhesive and a solvent-type adhesive.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

(Examples 1-4, Comparative Examples 1 and 2)
Tetrahydrofuran, methyl ethyl ketone, ethyl acetate, vinyl chloride-vinyl acetate copolymer (trade name “Solvine CN” manufactured by Nisshin Chemical Industry Co., Ltd., glass transition temperature: 75 ° C.), acrylic resin (trade name “Neocryl B- manufactured by Enomoto Kasei Co., Ltd.) 811 ”, glass transition temperature: 110 ° C.), fluorine-based surface conditioner (trade name“ Surflon S-651 ”manufactured by AGC Seimi Chemical Co., Ltd.) and silicone-based surface conditioner (trade name“ BYK-325, manufactured by BYK-Chem Japan ”). )) Was supplied to the glass bottle in the amount shown in Table 1 and mixed uniformly using a shaker to prepare a primer composition.

  The releasability, normal adhesive strength and heat-resistant creep of the obtained primer composition were measured in the manner shown below, and the results are shown in Table 1.

(Removability)
A primer composition was applied to the entire surface of a flat, rectangular plate-like base material (length 150 cm × width 50 cm) made of polyvinyl chloride at a thickness of 50 μm, and then dried at 20 ° C. for one week. Tetrahydrofuran in the composition was removed by evaporation to form a dry coating film on the surface of the substrate.

  On the other hand, a moisture curable hot melt adhesive (trade name “Sdyne 9627” manufactured by Sekisui Fuller) was prepared. The moisture curable hot melt adhesive was heated to 120 ° C. and melted. A moisture-curable hot-melt adhesive in a molten state was applied to the entire surface of a polyolefin resin sheet having a planar rectangular shape (length 150 cm × width 50 cm) and a thickness of 160 μm with a coating thickness of 50 μm.

Next, a moisture-curable hot-melt adhesive is placed on the substrate side of the polyolefin resin sheet on the dry coating film formed on the surface of the polyvinyl chloride plate-like substrate maintained at a surface temperature of 40 ° C. Then, a rubber roll was rolled on the polyolefin resin sheet to prepare a test piece. The test piece was allowed to stand for 10 minutes in an atmosphere at 20 ° C., and then the polyolefin resin sheet was peeled off from the surface of the base material by hand. The total area S ₁ of the moisture-curable hot melt adhesive remaining on the substrate surface after the polyolefin resin sheet was peeled from the substrate surface was measured. Residual rate (%) was calculated based on the following formula with the total area of the moisture-curable hot melt adhesive as S ₀ .
Residual rate (%) = 100 × S ₁ / S ₀

(Normal adhesive strength)
A primer composition is applied to the entire surface of a flat rectangular plate-shaped substrate made of polyvinyl chloride (length 150 cm × width 50 cm) at a thickness of 50 μm, and then dried at 20 ° C. for one week in the primer composition. The tetrahydrofuran was removed by evaporation to form a dry film on the surface of the substrate.

  On the other hand, a moisture curable hot melt adhesive (trade name “Sdyne 9627” manufactured by Sekisui Fuller) was prepared. The moisture curable hot melt adhesive was heated to 120 ° C. and melted. A moisture-curable hot melt adhesive in a molten state was applied to the entire surface of a polyolefin resin sheet having a planar rectangular shape (length 150 cm × width 50 cm) and thickness 180 μm with a coating thickness of 50 μm.

  Next, a moisture-curable hot-melt adhesive is placed on the substrate side of the polyolefin resin sheet on the dry coating film formed on the surface of the polyvinyl chloride plate-like substrate maintained at a surface temperature of 40 ° C. Then, a rubber roll was rolled on the polyolefin resin sheet to prepare a test piece.

  The test piece was allowed to stand for 1 hour in an environment at a temperature of 23 ° C. and a relative humidity of 55% to cool and solidify the moisture-curable hot melt adhesive. Thereafter, the test piece was left to stand in an environment of a temperature of 23 ° C. and a relative humidity of 55% for one week to cure the moisture-curable hot melt adhesive. Then, the polyolefin resin sheet was peeled from the surface of the substrate at a peeling angle of 180 ° and a peeling speed of 200 mm / min, and the average peel strength at this time was measured as normal adhesive strength (N / 25 mm).

(Heat resistant creep)
Test specimens were prepared in the same manner as normal adhesive strength. Next, the moisture-curable hot melt adhesive was cooled and solidified by leaving the test piece in an environment of 23 ° C. and 55% relative humidity for 1 hour. Next, the moisture-curable hot melt adhesive was moisture-cured by leaving the test piece in an environment of 23 ° C. and 55% relative humidity for 1 week.

  In a temperature environment of 60 ° C., the test piece was placed horizontally so that the polyolefin resin sheet was on the lower surface, and then at one end in the length direction of the polyolefin resin sheet, 500 g / 25 mm in the vertical direction. Weight was applied. After the elapse of 24 hours in this state, the length (mm) at which the polyolefin resin sheet was peeled off from the substrate surface was measured.

  In Table 1, it turns out that the primer composition of this invention is excellent in re-peelability and adhesiveness from contrast with an Example and a comparative example. Specifically, in comparison with Examples 1 and 2 and Comparative Example 1, when the organic solvent (A) is not an organic solvent capable of dissolving a polyvinyl chloride resin, ethyl acetate is used. However, when tetrahydrofuran and methyl ethyl ketone, which are organic solvents capable of dissolving the polyvinyl chloride resin, are used, it is understood that the adhesiveness is excellent. From the comparison between Example 3 and Comparative Example 2, it can be seen that the primer composition is excellent in removability by using a specific surface conditioner. By comparing Example 1 and Example 3, only vinyl chloride-vinyl acetate copolymer was used as the polymer (B) by using a vinyl chloride-vinyl acetate copolymer and an acrylic polymer in combination. It can be seen that the primer composition is more excellent in removability than the case where it was. Further, in comparison with Example 1 and Example 4, the primer composition when the fluorine-based surface conditioner is used as the surface conditioner (C) than when the silicone-based surface conditioner is used. It can be seen that is excellent in adhesiveness.

Claims (6)

  Containing an organic solvent (A) capable of dissolving the polyvinyl chloride resin, a polymer (B) soluble in the organic solvent, and a surface conditioner (C) for adjusting the surface tension of the dried coating film. A primer composition.   The primer composition according to claim 1, wherein the organic solvent (A) contains at least one organic solvent selected from the group consisting of acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and tetrahydrofuran.  The polymer (B) contains at least one polymer selected from the group consisting of polyvinyl chloride, vinyl chloride-vinyl acetate copolymer and acrylic resin. The primer composition described in 1.   The surface conditioner (C) contains at least one kind of conditioner selected from the group consisting of a fluorine-based surface conditioner, a silicone-based surface conditioner and an acrylic surface conditioner. The primer composition according to any one of the above.   The primer composition according to any one of claims 1 to 4, which contains 0.1 to 20 parts by mass of the polymer (B) with respect to 100 parts by mass of the organic solvent (A).   The primer composition according to any one of claims 1 to 5, wherein the primer composition contains 0.01 to 10 parts by mass of the surface conditioner (C) with respect to 100 parts by mass of the organic solvent (A). .