JPH09141788A - Film for protective and decorative coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film for forming a protective and decorative film on a molding simultaneously with an injection molding process, especially a molding with a three-dimensional curved face or a film almost free from a change in the color tone and luster deterioration in the area with a deeply drawn shape or a small curvature radial shape of a molding when this molding includes these shapes, and a film with the same color tone as a coat. SOLUTION: This film for protective and decorative coating consists of a base material layer A, a colored layer B and a transparent layer C. The base material layer A contains a copolymer of vinyl chloride resin and 5-30 pts.wt. of plasticizer and 0.5-50 pts.wt. of alkylester acrylate and alkylester methacrylate based on 100 pts.wt. of vinyl chloride resin, and is 100-300μm thick. The colored layer B contains an acrylic polymer with glass transition temperatures of 20-80 deg.C and a pigment, and is 5-50μm thick. The transparent layer C contains either one or a mixture of two or more selected from fluororesin, acrylic resin or urethane resin, and is 5-50μm thick. In addition, the base material layer A is formed on one of the faces of the colored layer B and the transparent layer C is formed on the other face.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a colored film having excellent appearance and weather resistance, and more specifically, a protective decoration capable of forming a decorative film simultaneously with injection molding on the surface of a molded product manufactured by an injection molding method. The present invention relates to a coating film.

[0002]

2. Description of the Related Art Conventionally, a decorative film mainly composed of an opaque or transparent vinyl chloride resin film colored with a pigment or the like has been used for protecting the surface of furniture or wall covering and improving the design. It is used for signboards, vehicle decorations, and painting alternatives. Since such a film is generally attached after the molded product is manufactured,
The ability to follow a cubic curved surface is insufficient, and it is difficult to apply it to a molded product such as an injection molded product having a small radius of curvature.

As a method for solving such problems and imparting a design to an injection-molded article, for example, Japanese Patent Publication No. 5-4.
In Japanese Patent No. 1089, a coating film (decorative film) obtained by laminating a metallic compound layer on a releasable film via a transparent layer (clear layer) is closely fixed to the mold surface of a mold cavity for injection molding. In Japanese Patent Publication No. 6-26718, a flexible decorative sheet is formed, and a substantially transparent outer layer made of acrylic resin, vinyl chloride or the like is used, and vinyl chloride or the like is used. A method has been proposed in which a colored layer containing reflective flakes is laminated and a sheet having an adhesive film formed thereon is attached at the same time as injection molding. It is said that such a method has an advantage that the process can be rationalized (the painting process is omitted) and the solvent discharge at the time of painting can be suppressed, as compared with the conventional designing method by painting. However, although the film used in the above technique has good followability to a cubic curved surface, when the target molded product also includes a deep-drawn shape or a shape with a small radius of curvature, the gloss decreases in this part. However, there is a problem that the color tone changes, and it is difficult to obtain the same appearance as that by painting.

[0004]

DISCLOSURE OF THE INVENTION The present invention is a film for forming a protective decorative film on the surface of an injection-molded product at the same time as molding. The molded product has a cubic curved surface, and in particular, this molded product has a deep drawing shape and a curvature. When including a shape with a small radius,
It is an object of the present invention to provide a film in which changes in color tone and deterioration in gloss in these parts are small.

[0005]

DISCLOSURE OF THE INVENTION As a result of intensive investigations by the present inventor regarding the above-mentioned problems relating to a film for forming a protective decorative film simultaneously with injection molding, the film has a specific composition and thickness. It was found that these problems can be solved by using a laminated body of layers, and the present invention has been completed.

That is, the gist of the present invention is a laminated film comprising a base material layer (A), a colored layer (B) and a transparent layer (C), wherein the base material layer (A) is a vinyl chloride resin and Resin 10
5 to 30 parts by weight of plasticizer and 0.5 to 50 parts by weight per 0 parts by weight
A thickness of 100 to 300 μm including a copolymer of alkyl acrylate and alkyl methacrylate by weight.
m, and the colored layer (B) has a glass transition temperature of 20 to
Thickness of 5 ° C including acrylic polymer and color pigment at 80 ° C
It is a layer of 50 μm, and the transparent layer (C) has a thickness of 5 to 50 μm, which is made of one kind of a fluororesin, an acrylic resin or a urethane resin or a mixture of two or more kinds thereof
And the base layer (A) on one side of the colored layer (B).
However, the present invention resides in a film for protective decorative coating, characterized in that the transparent layer (C) is formed on the other surface. Another subject matter of the present invention lies in the above-mentioned protective decorative coating film, wherein the alkyl group of the alkyl ester of acrylic acid and methacrylic acid has 1 to 8 carbon atoms.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The vinyl chloride resin used in the base material layer (A) of the present invention includes a homopolymer of vinyl chloride and a copolymer of vinyl chloride and another monomer copolymerizable therewith. As the other monomer copolymerizable with the vinyl chloride monomer, those generally used in the past can be used. Examples of the above-mentioned monomer include vinyl acetates such as vinyl acetate, vinyl propionate, and vinyl stearate,
Alkyl vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, octyl vinyl ether, lauryl vinyl ether and cetyl vinyl ether, α-olefins such as ethylene, monounsaturated acids such as acrylic acid and methacrylic acid, and methyl of these monounsaturated acids. Esters, alkyl esters such as ethyl esters, divalent unsaturated acids such as maleic acid, fumaric acid, itaconic acid, alkyl esters such as methyl esters and ethyl esters of these divalent unsaturated acids, vinylidene chloride such as vinylidene chloride Examples thereof include one kind or a mixture of two or more kinds of compounds and unsaturated nitriles such as acrylonitrile. These monomers are generally used in a proportion of 30% by weight or less, preferably 20% by weight or less with respect to the vinyl chloride monomer, but there is no particular limitation.

The vinyl chloride resin has an average degree of polymerization of 6
It is preferably from 0 to 1300, preferably from 700 to 1100. If the degree of polymerization is too low, the film for protective decorative coating (hereinafter referred to as "decorative film") will soften in the injection mold, and wrinkles will easily form on the surface of the molded product. Conversely, if the degree of polymerization is too high, it will become a decorative film. Molding becomes difficult, and elongation tends to be insufficient during injection molding, making it difficult to make deep-drawn products.

The plasticizer may be any as long as it is generally used for vinyl chloride resin films, and examples thereof include phthalic acid diester plasticizers such as di-2-ethylhexyl phthalate, diisononyl phthalate and di-n-octyl phthalate. , Trimeric acid triester plasticizers such as tri-2-ethylhexyl trimellitate and triisodecyl trimellitate, aliphatic diesters such as di-2-ethylhexyl adipate, diisononyl azelate and di-2-ethylhexyl sebacate. Basic acid diester plasticizers, aliphatic dibasic acids such as adipic acid, sebacic acid, azelaic acid and 1,2-propylene glycol, ethylene glycol, diethylene glycol, 1,3-butanediol, 1,4-butanediol Structure of polycondensation with various glycols Polyester plasticizers and epoxidized soybean oil, epoxidized linseed oil, and epoxy plasticizers such as epoxy resins. The blending amount of the plasticizer is 5 to 30 per 100 parts by weight of the vinyl chloride resin.
Parts by weight, preferably 8 to 20 parts by weight. The amount is 5
If it is less than 10 parts by weight, the workability at the time of molding the decorative film becomes insufficient, and if it exceeds 30 parts by weight, the decorative film is softened in the mold at the time of injection molding, and wrinkles are easily formed on the surface of the molded product.

The copolymer of alkyl acrylate and alkyl methacrylic acid (hereinafter referred to as "acrylic copolymer") used in the base material layer (A) is
It is preferable that the acrylic acid alkyl ester and the methacrylic acid alkyl ester are copolymerized at a ratio of 1: 3 to 3: 1. Further, those having 1 to 8 carbon atoms in the alkyl group are preferable, and preferable examples thereof include methyl acrylate, methyl methacrylate, ethyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate. May be used alone or in combination of two or more kinds. When the number of carbon atoms of the alkyl group exceeds 8, the processability during film formation of the film that will be the base material layer (A) tends to deteriorate. The number average molecular weight of the acrylic copolymer is 50,000 to 5
About one million is good. Vinyl chloride resin 1
0.5 to 50 parts by weight, preferably 1 to 100 parts by weight
5 parts by weight.

By blending a predetermined amount of a predetermined acrylic copolymer, strong adhesion between the base material layer and the colored layer can be obtained. If the compounding amount of the acrylic copolymer is out of the above range, the base material layer (A) and the coloring layer (B) described later may be peeled or peeled off by injection molding, resulting in a change in color tone and gloss of the decorative film. There is a risk of deterioration. The thickness of the base material layer (A) is 100 to 300 μm, preferably 120.
２５０250 μm. When the thickness is less than 100 μm, color unevenness is likely to occur due to the partial expansion and contraction when molded according to the curved surface of the molded product. Conversely, the thickness is 300 μm
If it exceeds, the heat capacity of the decorative film becomes large, so that a long time of preheating is required at the time of injection molding, or uneven coloring occurs due to uneven elongation.

Next, the acrylic polymer used for the colored layer (B) is a polymer of alkyl esters of acrylic acid or methacrylic acid such as methyl acrylate, methyl methacrylate and butyl acrylate, and a copolymer of these monomers. An acrylic polymer obtained by copolymerizing with another vinylic monomer such as polymerizable acrylic acid, or a mixture of these polymers, wherein acrylic acid and / or methacrylic acid in the acrylic polymer is The proportion of the alkyl ester is preferably 70 mol% or more,
Glass transition temperature is 20 ° C to 80 ° C, preferably 30 to 7
It is at 0 ° C. If the glass transition temperature is lower than 20 ° C, the average molecular weight of the acrylic polymer may be small, and the weather resistance of the decorative film may be poor. If it exceeds 80 ° C, the colored layer may be easily cracked during injection molding. As a result, the color tone of the decorative film may be changed and the gloss may be reduced. Further, in the present invention, 50% by weight or less of the acrylic polymer of the colored layer (B) may be replaced with a fluororesin such as polyvinylidene fluoride.

As the color pigment, aluminum,
Metal powders such as copper, titanium oxide, iron oxide, pearl essence, mica flakes or inorganic pigments whose surface is coated with titanium dioxide, or organic pigments such as cyanine or quinacridone. The amount of these coloring pigments to be used may be determined according to the required appearance, color tone, etc., but the range of 1 to 50 parts by weight is suitable for 100 parts by weight of the acrylic polymer. The colored layer (B) has a thickness of 5 to 50 μm, preferably 10 to 30 μm. When the thickness is less than 5 μm, the hiding property of the decorative film is lowered, and when it is more than 50 μm, the shape followability during injection molding becomes insufficient, resulting in a change in color tone and a decrease in gloss of the decorative film.

The transparent layer (C) is formed on the surface of the colored layer (B) which does not have the base material layer (A). The transparent layer (C) is made of any one of fluorine resin, acrylic resin and urethane resin, or a mixture of two or more thereof. As the fluororesin, polytetrafluoroethylene, polytrifluoroethylene, polyvinylidene fluoride, polyvinyl fluoride or a copolymer resin of a monomer constituting these fluororesins and a monomer copolymerizable therewith And mixtures of these resins and the like.

Examples of the acrylic resin include polymers of acrylic acid or methacrylic acid or their alkyl esters such as methyl ester and ethyl ester, and monomers of these and alkenylbenzenes and α which are copolymerizable therewith. Examples thereof include polymers with comonomers such as .beta.-unsaturated monomers and mixtures of these polymers.

As the urethane resin, polyols such as polyesters and polyethers having two or more hydroxyl groups in the molecule, and aliphatic or aromatic polyisocyanates having two or more isocyanate groups in the molecule. Examples thereof include a urethane resin obtained by reacting with and a mixture of these resins. The thickness of the transparent layer (C) is 5 to 5
It is 0 μm, and more preferably 10 to 30 μm.
When the thickness is less than 5 μm, the gloss of the decorative film is insufficient, and when it exceeds 50 μm, the shape followability during injection molding becomes insufficient, and the color tone of the decorative film changes and the gloss decreases.

In the base material layer (A), a vinyl chloride resin is blended with a predetermined amount of a plasticizer, a copolymer of an alkyl acrylate and an alkyl methacrylate, and various other additives for a vinyl chloride resin, Produced by mixing with a mixer such as a ribbon blender, Banbury mixer or super mixer to obtain a resin composition, and film-forming the resin composition by an extrusion molding method such as a T-die method or an inflation method, a calender method, or a casting method. can do.

The colored layer (B) and the transparent layer (C) may be formed in the same manner as the base material layer (A), or may be sequentially applied and formed as a coating liquid. Base material layer (A) and colored layer (B)
As a method for laminating the transparent layer (C), the above-mentioned three types of layers are prepared as films in advance, and the films are pressure-bonded with a heating laminator, or an acrylic or urethane adhesive is used. Examples of the method include a method of laminating using an agent, a method of forming a laminated body at the same time as film formation by a three-layer T-die or a three-layer inflation.

When the colored layer (B) and the transparent layer (C) are formed by coating as a coating liquid, the resin or the like used is dissolved or dispersed in a solvent such as toluene, methyl ethyl ketone or ethyl acetate, and the gravure roll coater is used. A reverse roll coater, a die coater, a flow coater or the like may be used to apply the coating by a conventional method. The obtained coating film is also dried by a commonly used hot air drying method, for example, 80 to 150.
It can be performed by heating at a temperature of ° C for 0.5 to 3 minutes.

In order to form a decorative film on the surface of a molded product simultaneously with injection molding using the decorative film of the present invention, an in-mold mold is attached to the injection molding machine, and the film feeding device is provided. Injection molding may be performed after the film is brought into close contact with the inner surface of the cavity of the injection molding die by an apparatus equipped with a film heating plate and a vacuum pump for film suction. Alternatively, the decorative film may be vacuum-molded in advance by a vacuum molding machine so as to fit the injection-molding die, and then the inner surface of the injection-molding cavity may be closely adhered to the injection-molding die.

[0021]

EXAMPLES Hereinafter, specific examples of the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless the gist thereof is exceeded. Preparation of Film (Examples 1 and 2, Comparative Examples 1 to 4) A vinyl chloride resin composition having the composition shown in Table 1 was mixed with a super mixer and then kneaded on a roll heated to 185 ° C. for 5 minutes. Then
Films a to f corresponding to the base material layer (A) were prepared.

Next, the colored layer (B) was applied and formed on one surface of each of the obtained films having various compositions. The colored layer (B)
Dissolves the acrylic polymer shown in Table 2 in a solvent (mixed solvent of methyl ethyl ketone: ethyl acetate = 6: 4) (solid concentration 20% by weight), and further prepares Asahi Kasei MF-
20 (non-leafing type aluminum paste) was added as solid content of 25% by weight to the acrylic polymer, and after mixing, the resulting acrylic coating was dried to a thickness of 15
It was applied with a bar coater to a thickness of 60 μm (60 μm for Comparative Example 3) and dried at a temperature of 120 ° C. for 3 minutes.
Further, the transparent layer (C) was applied and formed on the colored layer (B). The transparent layer (C) is used as a paint by Dainippon Color Materials Industry Co., Ltd.
The thickness of the urethane-based paint (trade name PU-701) after drying with a bar coater is 25 μm (3 for Comparative Example 4).
μm) and then dried in the same manner as above to prepare a decorative film.

Evaluation of Film Using the decorative film having the layer constitution shown in Table 3, an injection molding die (drawing ratio 0.11, minimum R5 mm) having a fixed frame for film insert was used, and the preheating temperature of the film was used. Injection molding was performed under the conditions of 100 ° C. and a resin temperature of 190 ° C. to form a decorative film on the surface of the molded product. The color difference (ΔE) between the part with a small radius of curvature (R5 mm part) of this molded product and the decorative film before injection molding was measured by Kurabo Industries C
It was measured by olor-7e ² type color difference meter.

In addition, the surface gloss (gloss) of this part is measured by a portable gloss meter (GM Color Research Laboratory, GM
X-202 type) was used, and both the incident angle and the reflection angle were measured at 60 °. (Represented as "60 ° gloss".) The color difference (ΔE) is 2.0 or less, and the gloss is a reflectance of 80%.
The above items were judged to be non-defective. Furthermore, the presence or absence of wrinkles on the surface of the injection molded product was visually determined.

[0025]

EFFECTS OF THE INVENTION By using the decorative film of the present invention, when a design having a glossy color tone is imparted to a molded article at the same time as injection molding, the glossiness is reduced or the color tone is reduced in a portion having a small radius of curvature of the molded article. Change and the appearance of the molded product is improved.

[0026]

[Table 1]

[0027]

[Table 2]

[0028]

[Table 3]

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Claims (2)

[Claims] 1. A laminated film comprising a substrate layer (A), a colored layer (B) and a transparent layer (C), wherein the substrate layer (A) is a vinyl chloride resin and 5 per 100 parts by weight of the resin. To 30 parts by weight of a plasticizer and 0.5 to 50 parts by weight of a copolymer of acrylic acid alkyl ester and methacrylic acid alkyl ester and having a thickness of 100 to 300 μm, and the coloring layer (B) has a glass transition temperature. Is a layer having a thickness of 5 to 50 μm and containing an acrylic polymer and a color pigment at 20 to 80 ° C., and the transparent layer (C) is any one of fluorine resin, acrylic resin or urethane resin or its 2 A layer having a thickness of 5 to 50 μm, which is composed of a mixture of at least one kind, and in which the base layer (A) is formed on one surface of the colored layer (B) and the transparent layer (C) is formed on the other surface. Characteristic protective decorative film. 2. The protective decorative coating film according to claim 1, wherein the alkyl group of the alkyl ester of acrylic acid and methacrylic acid has 1 to 8 carbon atoms.