JPS6111249A - Decorative coated article having excellent shock resistance and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides cosmetic coated articles with excellent appearance and adhesion that do not reduce the strength of the resin base material, especially impact resistance, in the cosmetic coating process, and This is a manufacturing method that is suitable for use in many applications such as automobiles, electronic equipment, and miscellaneous goods.

[Conventional technology and its problems]

Beautiful coatings are applied to the surfaces of plastic molded products for purposes such as decoration, improving surface hardness, giving them a metallic appearance or special functions, and are used in many applications such as automobiles, electronic equipment, and miscellaneous goods.

Beautiful painting methods include dipping, spraying, and brush painting.6 Paints include acrylic, acrylic/alkyd, amino/alkyd, urethane, acrylic/urethane, and epoxy. Types such as vinyl chloride/vinyl acetate copolymer, unsaturated polyester, melamine, and silicone are used. The biggest problem with cosmetic coatings using these paints is that strength, especially impact strength, decreases. Causes of this include swelling of the surface of the molded product due to low molecular weight compounds and solvents such as thinner contained in the paint, occurrence of cranks, and hardening phenomena due to curing.

Polycarbonate, whose greatest feature is impact strength, suffers a significant drop in impact strength when treated with cosmetic coatings, making cosmetic coatings unsuitable for applications that require high impact resistance.

In order to prevent such a decrease in impact strength, countermeasures have been taken for polycarbonate using materials and aesthetic coating techniques. In terms of materials, high molecular weight grades and blend modified grades are used. However, high molecular weight grades have poor moldability, especially fluidity, resulting in a high molding defect rate. In addition, blend modified grades have a decrease in heat resistance and weld strength. On the other hand, in terms of aesthetic painting techniques, there is a method of selecting a solvent that has less effect on polycarbonate, but this has the problems of narrowing the range of paints to choose from and reducing adhesion strength.

[Means for solving problems]

In order to improve the drawbacks of the conventional method as described above, the present invention
As a result of research on molding technology, they discovered a completely new method and succeeded in producing cosmetic coated polycarbonate articles with high impact strength.

That is, the present invention is a cosmetically coated article with excellent impact resistance, which is formed by laminating a thermoplastic plastic film or sheet that has been subjected to cosmetic coating treatment on one side and a resin layer formed by injection molding, and is preferable. In an embodiment, a thermoplastic film or sheet with a molecular weight of 25,000 is coated with a cosmetic coating on one side.
Composed of the above polycarbonate resin, the resin layer formed by injection molding has a molecular weight of 15,000 to 25.0.
This is a cosmetically painted article made of 00 polycarbonate resin.

The manufacturing method includes (1) punching out a thermoplastic plastic film or sheet that has been treated with an aesthetic coating on one side in the same shape as the aesthetically painted part of the molded product, and (2) creating a punched piece. a step of attaching a punched piece to a cavity portion corresponding to an aesthetically painted portion of an injection mold, (3) a step of closing the mold and high-pressure injection molding the molten resin by an injection molding means, and (4) a step of: In a preferred embodiment, a thermoplastic film or sheet, one side of which has been treated with an aesthetic coating, is coated with a thermoplastic film or sheet that has the same shape as the aesthetically painted portion of the molded article. A beauty product that consists of simultaneously performing the process of punching out a die to create a die-cut piece and the process of attaching the die-cut piece to a part of the leather cover corresponding to the aesthetically painted part of the injection mold when the mold is closed. The present invention provides a method for producing a coated article for wear.

Hereinafter, the present invention will be explained using the drawings.

FIG. 1 is a perspective view of a model molded article molded according to the present invention, and FIG. 2 is a sectional view taken along line A-A in FIG. 1. FIG. 3 is an enlarged view of part B in FIG. 2, in which a thermoplastic plastic film or sheet 5 that has been painted on one side for aesthetic purposes and a resin layer 6 formed by injection molding of molten resin are laminated together. has been made into Furthermore, FIG. 4 is an explanatory diagram schematically showing the injection molding process according to the present invention, in which a thermoplastic plastic film with a cosmetic coating applied to one side, or The sheet 5 is thermally fused and integrated with the molten resin layer 6 flowing through the gate 4.

Here, the thermoplastic plastic film or sheet 5 applied to one side before cosmetic painting can be easily fixed to the mold cavity using static electricity, suction force such as vacuum, or other conventionally known methods. .

As explained above using drawings, the cosmetic coated article and the manufacturing method thereof according to the present invention are applied to various molded products, such as frames, fixtures, and other original functional parts of molded products. The mode of integrally molding in an injection molding process is naturally adopted in a practical system.

〔Example〕

Examples will be explained below.

Example 21 Extrusion molded molecular weight ao, ooo, thickness 2001tW
l polycarbonate film (500m x 600m
) was coated with an acrylic urethane paint (trade name: Planet P, manufactured by Origin Denki ■) by spray painting and cured at 70°C for 30 minutes.

The polycarbonate film obtained above, with one side of which has been painted for aesthetic purposes, was punched out to the same dimensions using a Thomson blade, and then attached to a circular injection mold with a diameter of 102 mm and a thickness of 3.2 mm. did. The mounting was carried out by providing a minute vacuum suction hole in the mold and holding it by vacuum.

Injection molding was performed using polycarbonate having a molecular weight of 23,000 in this mold.

In the obtained disc, the cosmetic coating film and the molded resin material were completely integrated, and no boundary line was discernible. Also,
No damage to the cosmetic paint film or abnormal appearance was observed.

City! As a comparative example, the above-mentioned paint was directly spray-coated on one side of an injection-molded disc made of polycarbonate having a molecular weight of 23,000, and cured at 70°C for 30 minutes.

Use 10 pieces each of this disc and the above disc, and hold them with the opposite side of the cosmetically painted side facing up, and the weight will be 2.3 kg.
When a weight of sr was dropped from a height of 2 m and the number of sheets that underwent ductile deformation or ductile fracture and the number of sheets that suffered brittle fracture were determined, in the example, 10 sheets were ductile deformed or ductile fractured, and 0 sheets were brittle fractured. In the comparative example, the former numbered 3 and the latter 7.

[Operation and effects of the invention]

As explained above in detail, the cosmetic coated article of the present invention and its manufacturing method are as follows: (1) Even when a low-viscosity injection molding material with good moldability is used, a cosmetic coated article with high impact strength can be obtained. .

(2) Since the film or sheet is made by extrusion molding or casting, molding distortion is small, and compared to injection molded products, there is virtually no occurrence of cranking due to molding distortion during the cosmetic painting process. , high molecular weight grade can be used, so it has excellent durability.

(3) Since a film or sheet that has been aesthetically painted under certain conditions is used, quality is stable and productivity is high.

(4) Unlike conventional methods, there is no need for annealing treatment before cosmetic painting.

(5) Partial cosmetic painting is easy.

etc.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a model injection molded product for explaining the cosmetic painted molded product of the present invention, Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1, and Fig. 3 is a cross-sectional view of part B in Fig. 2. The partially enlarged view, FIG. 4, is a schematic diagram illustrating the state of injection molding of the model molded product of the present invention. The numbers in the diagram are respectively: 1: Beautiful painted molded product, 2: Varnish blue, 3: Runner,
4: gate, 5: single-sided cosmetic coating film or sheet, 6: resin layer formed by injection molding, 7.7°: mold. Patent applicant: Mitsubishi Gas Chemical Co., Ltd. Representative: Kazuyoshi Nagano

Claims (1)

[Scope of Claims] 1. A cosmetic coated article with excellent impact resistance, which is made by laminating a thermoplastic plastic film or sheet that has been subjected to cosmetic coating treatment on one side and a resin layer formed by injection molding. 2. A thermoplastic plastic film or sheet with a cosmetic coating applied to one side is made of polycarbonate resin with a molecular weight of 25,000 or more, and the resin layer formed by injection molding has a molecular weight of 15,000 to 25,000.
A cosmetic coated article according to claim 1, which is made of a polycarbonate resin. 3. (1) A step of punching out a thermoplastic plastic film or sheet that has been subjected to aesthetic painting on one side in the same shape as the aesthetically painted part of the molded product to create a punched piece, (2) Injecting the punched piece. (3) closing the mold and high-pressure injection molding the molten resin by injection molding means; and (4) removing the mold from the mold. A method for manufacturing a cosmetic coated article, which includes a step of taking out a molded article. 4. The process of punching out a thermoplastic plastic film or sheet with an aesthetic coating on one side in the same shape as the aesthetically painted part of the molded product, and the process of creating a punched piece and applying the aesthetic coating to the injection mold. 4. A method for manufacturing a cosmetic coated article according to claim 3, which comprises simultaneously carrying out the step of installing the coated article into a cavity portion corresponding to the wear coated portion at the same time as the step of closing the mold.