JPS63135215A - Plastic injection molding - Google Patents

Abstract

PURPOSE:To obtain a plastic injection molding with high decorativeness in design by a structure wherein designs, which are transferred simultaneously with injection molding, are provided on a part of the surface of a molding and irregularities, which are the transfers of the fine irregularities made on the inner surface of an injection mold, are provided in the parts corresponding to the designs. CONSTITUTION:In order to manufacture a plastic injection molding concerned, a transfer sheet having designs 3 is arranged in an injection mold 5 having irregularities 4 so as to perform injection molding. The designs to be transferred are preferably formed by printing 31 by any means such as gravure printing or the like, depositing 32 of metal such as aluminum or the like or the combination of depositing and etching of metal. The optimum transparent or translucent plastic material is acrylic resin. In addition, when fine irregularities 4 are pattern by hairline 42 and designs 3 on the rear side of a part corresponding to said fine irregularities 4 are applied by depositing 32 of metal, the external appearance represented by metal finished by hairline is shown, because the deposited surface is seen through the transparent or translucent plastic.

Description

[Detailed description of the invention]

”L Watarui

[Industrial application field]

The present invention relates to a plastic injection molded product made by index molding plastic and having a transferred design and fine irregularities associated therewith.

[Conventional technology]

During plastic injection molding, a transfer sheet is placed in a mold to transfer a design onto a molded product, a technique known as "decoration molding." On the other hand, it is also known that by providing minute irregularities on the inner surface of an injection mold, it is possible to obtain a plastic injection molded product with a surface that conforms to the irregularities. Generally, the application is done on the outside of the molded product, which can be seen from the outside, but if transparent or translucent plastic material is used, even if the application is applied on the inside, it can be seen through the molded product. . However, plastic injection molded products that cost 1q are not particularly attractive.

[Problems to be solved by the invention]

An object of the present invention is to provide a plastic injection molded product with a high design quality that produces unique effects by combining the above-mentioned existing techniques. Structure of the Invention [Means for Solving the Problems] As shown in FIGS. 1 and 2, a plastic injection molded product 1 of the present invention is made by injection molding a transparent or translucent plastic, and has a surface that is made of transparent or translucent plastic. This is a plastic injection molded product which has a pattern 3 transferred at the same time as the injection molding in one part, and has fine irregularities 4 corresponding to the fine irregularities on the inner surface of the injection mold in the corresponding part. In the example shown in the figure, there is a pattern 3 on one side of the plastic molded product, and fine irregularities 4 on the opposite side. From this example, "correspondence" means that there are fine irregularities on the surface of the plastic molded product in a different part from the part where the pattern is placed, and that the two overlap when seen through the transparent or translucent plastic. It will be easily understood that this includes cases where the combination of the pattern and minute irregularities can produce the unique effects described below. Of course, this also includes cases where the surface of the patterned part itself has minute irregularities. As shown in Figs. 1 to 3, the "fine irregularities" are typically matte 41, hairline 42, or satin pattern formed by sandblasting, but other types can also be molded in the present invention. Of course, it can be used as long as it corresponds to the design and produces the effect described below.
They are also included. Further, the term "design" includes not only a specific pattern or design but also solid coloring that occupies a certain area. In order to produce the plastic injection molded product of the present invention, a third step is required.
As shown in the figure, injection molding may be performed by placing a transfer sheet 2 having a pattern 3 in an injection mold 5 having fine irregularities 4. Production of transfer sheets and painting using them are
Known techniques can be followed. That is, a transfer sheet in which a desired protective layer, printing layer, and adhesive layer are laminated on a suitable releasable base material is preformed and used, if necessary. The pattern to be transferred is as shown in Figures 1 and 3.
It may be formed by printing 31 by any means such as gravure printing, vapor deposition 32 of metal such as aluminum, or a combination of vapor deposition and etching. Acrylic resin is most suitable as a transparent or translucent plastic material, but polyethylene, As resin, polycarbonate, etc. are also useful. In addition, any transparent or translucent thermoplastic or thermosetting resin can be used as long as it can be injection molded. [Function] In the plastic injection molded product of the present invention, for example,
As shown in FIGS. 1 and 2, when the fine unevenness 4 is made into a hairline 42 pattern and the pattern 3 is applied to the back side by metal vapor deposition 32, the vapor-deposited surface is coated through transparent or translucent plastic. As a result, it looks like metal with hairlines. Such an appearance cannot be obtained by a smooth transfer of vapor-deposited metal or by mere irregularities on the surface of the plastic, but is produced as a result of the two overlapping on the line of sight through the transparent or translucent plastic. Similarly, as shown in FIGS. 1 and 2, if there is a matte surface 41 made of sandblast or the like in front of the appropriately colored pattern 3, when looking at it through transparent or translucent plastic, the matte surface 41 It looks as if it has been painted over, creating a special effect similar to the above. Effects of the Invention The plastic injection molded product of the present invention has a high degree of design that cannot be obtained with conventional molded products or molded products with a matte surface. Therefore, this plastic injection molded product is suitable as parts for office automation equipment, automobile parts, furniture, and the like.

[Brief explanation of the drawing]

1 and 2 show an example of the plastic injection molded product of the present invention, with FIG. 1 being a sectional view and FIG. 2 being a plan view. FIG. 3 is a cross-sectional view centered on the injection mold for explaining the method of manufacturing the plastic injection molded product shown in FIGS. 1 and 2. FIG. 1...Plastic injection molded product 2...Transfer sheet 3...Design 31...Printing 32...Metal vapor deposition 4...
・Minute unevenness 41...Matte 42...Hairline 5・
...Injection molding mold patent applicant Dainippon Printing Co., Ltd. agent Patent attorney Sou Suga Disqualification Figure 1 Figure 2

Claims (3)

[Claims] (1) It is made by injection molding transparent or translucent plastic, and a part of the surface has a pattern that was transferred at the same time as the injection molding, and a corresponding part has the fine irregularities on the inner surface of the injection mold. A plastic injection molded product with fine irregularities. (2) The plastic injection molded product according to claim 1, wherein the transferred design is formed by printing or metal vapor deposition. (3) The plastic injection molded product according to claim 1, wherein the fine irregularities are matte, hairline, or satin patterned.