JP3500235B2 - Manufacturing method of acrylic insert film and acrylic insert molded product - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a surface material for furniture,
Interior / exterior materials for construction, surface materials for cabinets, interior materials for kitchen doors, materials used as automobile interior parts, etc., and acrylic insert films used for producing insert molded products by forming patterns such as wood grain patterns. It belongs to the technical field relating to a method for producing an acrylic insert molded product using this insert film.

[0002]

2. Description of the Related Art Conventionally, an insert molded article obtained by an insert molding method is used as a material used as an automobile interior part having a pattern such as a grain pattern formed thereon. The insert molding method is to place an insert film in which a pattern ink layer such as a wood grain pattern ink layer is printed on an acrylic film base in an injection molding die, heat the insert film, and close the die to melt the molten resin. This is a method of adhering the ink layer side of the acrylic insert film to a resin molded product by injecting it into a mold and solidifying the resin.

The reason why the acrylic film substrate is used is that the acrylic film has a superior light resistance as compared with a PET film because the acrylic film has a molecular structure that makes it difficult for light rays harmful to ink to pass therethrough. An advantage of excellent "light resistance" is that, for example, fading or damage of the design ink layer caused by direct exposure of natural light or room light to the design ink layer can be effectively suppressed. Further, since the acrylic film deforms (elongates) even at a low temperature, the workability of the entire insert film is superior to that of the PET film and the like. The advantage of excellent "workability" is that, for example, the shape of the inner surface of the cavity of the injection mold is a complicated shape such as unevenness with many holes and grooves, Even if the insert film uses an acrylic film as the base sheet, it has a complicated shape and a deep rise on the inner surface of the cavity of the injection mold due to heating and vacuum suction. This is because it is possible to obtain an insert-molded product that is deformed into a shape and exhibits a surface shape similar to the shape of the inner surface of the cavity of the injection molding die.

[0004]

Problems to be solved by the conventional acrylic insert film will be described below. The acrylic film comes to the outermost surface of the insert molded product to protect the pattern ink layer. Acrylic films have excellent light resistance and workability, but on the other hand, they are inferior in chemical resistance and stain resistance to PET films and the like, so acrylic insert molded products are inferior in chemical resistance and stain resistance. It becomes a thing. For example, when the liquid of the hair styling material or alcohol adheres to the insert molded product, the film surface becomes irritated,
If the oil-based magic ink sticks firmly to the insert-molded product and cannot be wiped off easily, place a license case made of vinyl chloride on the insert-molded product to keep the license under hot weather. Various problems occur, for example, when the case is fused and adheres to the insert-molded product, which makes it difficult to peel it off easily.

The problems of the conventional method for manufacturing an acrylic insert molded product are shown below. Since the acrylic film is excellent in processability, the shape of the inner surface of the cavity of the injection molding die is complicated such as unevenness with many holes and grooves formed, or it is composed of concave parts with deep rising. Even if the shapes are different, they are deformed and adhere to each other. Therefore, in the conventional method for manufacturing an acrylic insert-molded product, the more uneven the shape of the cavity inner surface of the injection mold, and the deeper the recess is, the more the acrylic film and the mold of the acrylic insert-molded product The contact area becomes large, and the number of places where the acrylic film of the acrylic insert-molded product bites into the cavity inner surface increases. As a result, a lot of friction and catching occur, making it difficult to take out the acrylic insert-molded product from the cavity, resulting in poor production efficiency.

The present invention solves the above-mentioned drawbacks and has not only good light resistance and workability but also excellent chemical resistance and stain resistance, and an acrylic insert molding with good production efficiency. It is intended to provide a method for manufacturing a product.

[0007]

In order to achieve the above object, the acrylic insert film of the present invention has a surface of a transparent base sheet containing an acrylic resin as a main component, as described in claim 1. A transparent overcoat layer having a fluorine-based copolymer resin was formed on the above, and a pattern ink layer and an adhesive layer were sequentially formed on the back surface.

Further, as described in claim 2, the acrylic insert film of the present invention is structured such that the pattern ink layer in claim 1 is composed of a wood grain layer and an opaque underlayer.

The acrylic insert film of the present invention is, as described in claim 3, a transparent overcoat having a fluorine-based copolymer resin on the surface of a transparent first substrate sheet containing an acrylic resin as a main component. A coat layer is formed, and a wood grain layer, a laminating adhesive layer, a transparent second base sheet containing an acrylic resin as a main component, an opaque underlayer on the back surface,
The adhesive layer was formed sequentially.

According to a fourth aspect of the present invention, in the method for producing an acrylic insert molded article, the acrylic insert film of the present invention is placed in a mold for injection molding, the acrylic insert film is heated, and After closing, the molten resin was injected into the mold and the resin was solidified to bond the acrylic insert film to the resin molded product.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing an acrylic insert film and an acrylic insert molded article according to the present invention will be described in more detail below.

In the acrylic insert film of the present invention, a transparent overcoat layer 2 having a fluorocopolymer resin is formed on the surface of a transparent substrate sheet 1 containing an acrylic resin as a main component, and a pattern ink layer is formed on the back surface. (Wood grain layer 4, opaque base layer 5) and adhesive layer 6 are sequentially formed (FIG. 1).

The transparent substrate sheet 1 is a transparent resin sheet containing an acrylic resin as a main component. A transparent resin sheet containing an acrylic resin as a main component has a molecular structure that makes it difficult for light rays harmful to ink to pass therethrough, and therefore has excellent light resistance as compared with a PET film or the like.
An advantage of excellent "light resistance" is that, for example, fading or damage of the design ink layer caused by direct exposure of natural light or room light to the design ink layer can be effectively suppressed. Further, since the transparent resin sheet containing an acrylic resin as a main component is deformed (stretched) even at a low temperature, the workability of the entire insert film is superior to that of a PET film or the like. The advantage of being excellent in "workability" is that, for example, the shape of the inner surface of the cavity 70 of the injection molding die 7 is a complicated shape such as unevenness with many holes or grooves formed. Even if it has a shape with deep rising recesses, an insert film using a transparent resin sheet containing an acrylic resin as a main component as a base sheet can be heated or vacuum sucked into an injection molding die. That is, it is possible to obtain an insert-molded product that is deformed to have a complicated shape or a deep rising shape of the inner surface of the cavity 70 of 7 and has a surface shape of the inner surface of the cavity 70 of the injection molding die 7. .

As the transparent base sheet 1 containing an acrylic resin as a main component, not only an acrylic film made of a pure acrylic resin such as polymethylmethacrylate, polyethylmethacrylate, polypropylmethacrylate, polybutylmethacrylate, etc. , A film of a component composed of a copolymer of an acrylic resin and another resin (for example, a fluororesin, a polystyrene resin, a polypropylene resin, a polyvinyl chloride resin, a polyester resin, a silicone resin), an acrylic film and another plastic film ( For example, a laminated film with a fluorine film, a polypropylene film, a polyvinyl chloride film, a polyester film, a polyethylene vinyl acetate film, a polycarbonate film, etc.) is also included. As a method for laminating the laminated film, there are various laminating methods such as direct laminating and dry laminating and methods by a heat sealing method. When a biaxially stretched polyester film or a biaxially oriented polypropylene film and a pure acrylic film are laminated to form a base sheet, the elongation of the film is worse than that of the pure acrylic film. It is preferable to use a relatively thin film as the polypropylene film rather than a pure acrylic film.

The thickness of the base sheet 1 is 10 μm to 500 μm.
Although it is μm, it is preferably 50 μm or more in order to obtain sufficient light resistance. Also, in order to obtain sufficient workability, 30
It is preferably 0 μm or less. In the case of methyl methacrylate, the thickness for simultaneously having good light resistance and good workability is 125 μm or 200 m.

The fluorocopolymer resin used in the overcoat layer 2 is a fluorocopolymer having a methacrylic group. As a specific example thereof, polyvinylidene fluoride-
Methyl methacrylate copolymer, tetrafluoroethylene-methyl methacrylate copolymer, tetrafluoroethylene-methyl methacrylate copolymer, chlorotrifluoroethylene-methyl methacrylate copolymer, hexafluoroethylene-methyl methacrylate copolymer Examples thereof include coalesce, fluoroethylene-methyl methacrylate copolymer, fluoroolefin-methyl methacrylate copolymer and the like.
A cross-linking agent such as polyisocyanate or melamine resin may be added to these resins. The overcoat layer 2 may be an ink layer formed on the base sheet 1 by various printing methods or coating methods, or one in which the base sheet 1 and the film-shaped overcoat layer 2 are laminated by a coextrusion method. But it's okay. The overcoat layer preferably has a thickness of 0.5 μm to 5 μm. The printing method includes an offset printing method, a gravure printing method, a screen printing method, and a flexo printing method. Examples of the coating method include a roll coating method and a spray coating method. As a specific example of the co-extrusion method, the substrate sheet 1 is extruded by an extruder to be extruded into a film-shaped or sheet-shaped substrate sheet, and at the same time, the overcoat layer 2 is extruded by an extruder to form a film-shaped or sheet-shaped overcoat. The layer 2 is formed on the surface of the base sheet 1 to form a sheet having a two-layer structure.

The fluorine-based copolymer resin used for the overcoat layer 2 includes, for example, those having a fluorine content in the methacrylate monomer unit of about 5% to about 50%. The fluorine content in the methacrylate monomer unit means a percentage of (weight of only fluorine in methacrylate monomer) / (weight of all methacrylate monomer including fluorine). When the fluorine content in the methacrylate monomer unit is about 5% or less, the effects of chemical resistance and stain resistance cannot be sufficiently obtained.
When the content of fluorine in the methacrylic acid monomer unit is about 50% or more, the film of the overcoat layer 2 is easily repelled by the transparent base sheet 1 containing an acrylic resin as a main component, or the acrylic resin is a main component. The overcoat layer 2 may easily be easily peeled off from the transparent substrate sheet 1. In order to sufficiently obtain the effects of chemical resistance and stain resistance, a solvent-soluble fluorine-based copolymer having a fluorine content in the methacrylate monomer unit of 30% to 40% is particularly suitable.

As for the film thickness of the overcoat layer 2, taking a tetrafluoroethylene-methyl methacrylate copolymer as an example, the film thickness is 2 μm when the fluorine content is 20%, and the fluorine content is 45%. Has a film thickness of 0.7 μm. Particularly, when the fluorine content is 35%, the film having a film thickness of 1 μm can sufficiently obtain the effects of chemical resistance and stain resistance.

The design of the design ink layer includes wood grain design, characters, symbols, numbers and the like. Hereinafter, as an example of the pattern ink layer, a wood grain pattern layer including the wood grain layer 4 and the opaque base layer 5 will be described. The pattern ink layer may be formed by using various pigments or dyes, or a bright pigment ink layer mixed with pearl powder or aluminum powder, or a metal vapor deposition layer.

The wood grain layer 4 is a layer for expressing a wood grain pattern such as annual rings, fibers and conduits that appear at the cut end when the wood is cut. Specific wood grain patterns include streaks, curved lines, and line breaks. The wood grain layer 4 uses a thermoplastic resin such as vinyl chloride / vinyl acetate copolymer, polyamide, polyester, polyacrylic, polyurethane, chlorinated rubber, or nitrified cotton as a binder, and contains a dye or pigment having a wood grain pattern as a coloring material. Select one or multiple colors from brown, dark brown, ocher, reddish brown, etc. The wood grain layer 4 is formed by a usual printing method such as an offset printing method, a gravure printing method, a screen printing method, a flexographic printing method, or a coating method such as a roll coating method or a spray coating method. Alternatively, wood grain layer 4
May be formed on a part or the whole surface of the base sheet 1 by gradation so that the color density or the film thickness is changed stepwise or continuously in order to make it closer to the natural wood grain pattern. The thickness of the wood grain layer 4 is 0.5μ
Adjust within the range of m to 5 μm.

The opaque underlayer 5 is a layer that expresses the color of the wood other than the wood grain that appears at the cut end when the wood is cut. The opaque underlayer 5 contains a thermoplastic resin such as vinyl chloride / vinyl acetate copolymer, polyamide, polyester, polyacryl, polyurethane, chlorinated rubber, or nitrified cotton as a binder, and contains a dye or pigment of the underlayer color as a coloring material. Select a single or multiple colors from brown, dark brown, ocher, cream, yellow, reddish brown, etc. If necessary, the color may be selected to be darker than the color selected for the wood grain layer 4, or may be selected to be a light color. The opaque base layer 5 is formed by a usual printing method such as an offset printing method, a gravure printing method, a screen printing method, a flexographic printing method, or a coating method such as a roll coating method or a spray coating method. The suitable thickness of the opaque underlayer 5 is 2 μm to 10 μm.

The adhesive layer 6 may be made of acrylic resin, urethane resin, polyester resin, polyamide resin, ethylene butyl alcohol resin, ethylene vinyl acetate copolymer, vinyl chloride / vinyl acetate copolymer, or the like.

Further, the acrylic insert film of the present invention has a transparent first base sheet 10 containing an acrylic resin as a main component and a transparent second base sheet 11 containing an acrylic resin as a main component. A transparent overcoat layer 2 made of a fluorocopolymer resin on the surface of the sheet 10.
Is formed, and the wood grain layer 4, the laminating adhesive layer 3,
The second base sheet 11, the opaque base layer 5, and the adhesive layer 6 are sequentially formed (FIG. 2). In this configuration, since the wood grain layer 4 and the opaque base layer 5 are separated with the second base sheet 11 sandwiched therebetween, it is possible to obtain a wood grain pattern having a three-dimensional effect in which the wood grain is raised from the base. Is advantageous. The first base sheet 10 and the second base sheet 11 are
It is the same as the base sheet 1. The method of stacking the first base sheet 10, the wood grain layer 4, and the second base sheet 11 is as follows.
For example, the first base sheet 10 on which the wood grain layer 4 is formed and the second base sheet 11 are laminated with the laminating adhesive layer 3 and laminated.

The method for producing an acrylic insert molded article of the present invention is a method for producing the acrylic insert film by the insert molding method using the acrylic insert film. That is, the acrylic insert film is placed in a mold for injection molding, and after the mold is closed, a molten resin is injected into the mold and the resin is solidified to bond the acrylic insert film to the resin molded product. Yes (Figure 3,
4, 5).

The injection molding die 7 used in this manufacturing method comprises a movable die and a fixed die. When arranging the acrylic insert film in the injection mold, the individual acrylic insert films may be fed and arranged one by one, or the necessary parts of the long acrylic insert film may be intermittently fed and arranged. You may. When a long acrylic insert film is used, it is advisable to use a feeder having a positioning mechanism so that the pattern layer of the acrylic insert film and the molding die are in register. Further, when the acrylic insert film is intermittently fed and arranged, if the position of the acrylic insert film is detected by the sensor and then the acrylic insert film is fixed by the movable mold and the fixed mold, the acrylic insert film is always at the same position. It is convenient because the insert film can be fixed and the position of the design of the design ink layer does not shift. After the acrylic insert film is arranged, the acrylic insert film is brought into close contact with the inner surface of the movable concave portion (the concave portion may also be referred to as “cavity”) by vacuum suction or heating. Then, the injection molding die is closed to form the cavity 70 (FIG. 3). The cavity 70 is injected and filled with the molten resin 9 through the injection port 8 provided in the fixed mold, and the resin is solidified to form the resin molded product 12, and at the same time, the acrylic insert film is adhered to the surface thereof. After cooling the resin molded product 12,
Open the molding die and take out the resin molded product. In this way, an acrylic insert molded product can be obtained.

[0026]

Example A 200 μm thick methyl methacrylate film was used as the base sheet. On the surface of the base sheet,
An overcoat layer made of a fluorine-substituted poly (methyl methacrylate) resin having a fluorine content of 30% was formed by a gravure printing method. A wood grain layer (weight%: resin binder / pigment = 60/40) made of a resin binder made of a polyvinyl chloride resin and a brown pigment was formed on the back surface of the base sheet by a gravure printing method. An opaque underlayer (% by weight: resin binder / pigment = 60/40) made of a resin binder made of a polyvinyl chloride resin and a black pigment is provided on the wood grain layer.
It was formed by a gravure printing method. An adhesive layer made of vinyl chloride vinyl acetate copolymer resin was formed on the opaque underlayer by a gravure printing method to obtain an acrylic insert film having a grain pattern.

The wood grain pattern acrylic insert film obtained as described above is placed in an injection molding die consisting of a movable die and a fixed die for producing a gear box panel, and the acrylic insert film is heated to 95 ° C. Vacuum suction was performed while heating at, and it was brought into close contact with the concave portion of the movable mold. After closing the mold, while maintaining the mold temperature at 40 ° C to 60 ° C, 220
A molten resin composed of a brown acrylonitrile butadiene styrene copolymer resin heated to ℃ to 250 ℃ was injected into the mold to solidify the resin.

The resulting acrylic insert-molded article had sufficient resistance to the attachment of hair styling agents and to the adhesion of oil-based magic ink, and no cracks were generated on the surface. Resistance to adhesion of hairdressing agent means that after applying the hairdressing agent to the entire acrylic insert molded product, cover it with a cloth and keep it at 40 ° C.
It means that the surface does not become irritated even after putting it in the incubator for 24 hours. What is the resistance to the adhesion of oil-based magic ink?
It means that no marks of magic ink are left when you write letters on an acrylic insert molded product with oil-based magic and wipe it off with a dry cloth.

[0029]

Since the present invention has the above-mentioned structure and operation, the following effects can be obtained. That is, since the acrylic insert film of the present invention uses a transparent sheet containing an acrylic resin as a main component as a base sheet of the insert film, it has excellent light resistance and workability. Further, since the transparent overcoat layer made of the fluorocopolymer resin is present on the base sheet, the overcoat layer supplements the weaknesses of the acrylic sheet, such as chemical resistance and stain resistance.
Therefore, the acrylic insert film of the present invention can be used for producing an acrylic insert molded article having excellent light resistance, processability, chemical resistance, and stain resistance.

The method for producing an acrylic insert-molded article of the present invention uses an acrylic insert film having a transparent sheet containing an acrylic resin as a main component as a base sheet and has good workability. It is possible to obtain an insert-molded product that is deformed to have a complicated shape of the cavity inner surface of the injection molding die or a deep rising shape, and has a surface shape similar to the shape of the cavity inner surface of the injection molding die. Furthermore, since an insert film with a transparent overcoat layer made of a fluorocopolymer resin on the base sheet is used, the overcoat layer functions as a lubricant and wear resistance when the acrylic insert molded product is taken out. Exert its abilities. Therefore, friction and catch with the mold are less likely to occur, the mold is not damaged, and the acrylic insert-molded product can be easily removed from the cavity, so that the production efficiency of the insert-molded product is surely improved. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of an acrylic insert film of the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of another aspect of the acrylic insert film of the present invention.

FIG. 3 is a cross-sectional view showing one of the manufacturing steps of the acrylic insert-molded product of the present invention.

FIG. 4 is a cross-sectional view showing one of the manufacturing steps of the acrylic insert-molded product of the present invention.

FIG. 5 is a sectional view showing an acrylic insert molded product of the present invention.

[Explanation of symbols]

1 Base sheet 2 Overcoat layer 3 Laminating adhesive layer 4 wood layers 5 Opaque underlayer 6 Adhesive layer 7 Injection mold 8 exit 9 Molten resin 10 First Base Sheet 11 Second base sheet 12 Resin molded products

Claims (2)

(57) [Claims] 1. A transparent first resin containing an acrylic resin as a main component.
A transparent overcoat layer having a fluorocopolymer resin is formed on the surface of the base sheet, and a wood grain layer, a laminating adhesive layer, a transparent second base sheet containing an acrylic resin as a main component, and an opaque underlayer on the back surface. An acrylic insert film, in which an adhesive layer is sequentially formed. 2. The acrylic insert film according to claim 1 is placed in a mold for injection molding, the acrylic insert film is heated, and after closing the mold, a molten resin is injected into the mold to solidify the resin. A method of manufacturing an acrylic insert-molded product, which comprises bonding the acrylic insert film to the resin-molded product by performing the above.