JPS58185231A - Manufacture of plastic molded product having foamed layer shaped on its surface - Google Patents

Abstract

PURPOSE:To manufacture the plastic molded product having a feeling near to a flocked product at an extremely low cost, by printing a heat foamable ink on the surface of a plastic sheet and shaping a foamed layer by foaming said ink by heating. CONSTITUTION:A heat foamable ink 2 is printed on the surface of a thermoplastic sheet 1 and the heat foamable ink 2 is foamed by heating by a heating element. Then the molded product having a foamed layer (a) is manufactured by forming.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a plastic molded article having a foam layer formed on its surface.

Plastic and molded products are often used as containers, inner frames within containers, decorative lids, etc., but their textures have the disadvantage of giving the impression of being cheap.

Therefore, 1. Conventionally, attempts have been made to improve the texture by means such as coloring or flocking, but only by coloring, almost no improvement is observed. In addition, methods such as flocking can give the impression of a high-class product in terms of the texture of the surface 02, but they have the disadvantage that they are expensive and cannot be used for anything.

In view of this, the present invention aims to provide a plastic molded product similar to the above-mentioned flocked product that can be manufactured at an extremely low cost.The present invention consists of printing a thermofoamable ink on the surface of a thermoplastic sheet. Then, this plastic sheet is heated to foam the thermofoamable ink, and at the same time it is molded using a mold to obtain a plastic molded product.The foamed layer is formed on the surface of the product by the foaming of the thermofoamable ink. The aim is to enhance the texture through the action of this foam layer. Further, when a product is obtained by the above manufacturing method, it has the advantage that the cost is very low.

Embodiments of the present invention will be described in detail below. First, as shown in FIG. 1, a thermofoamable ink 2 is printed on the surface of a thermoplastic sheet 1. This printing may be done on the entire surface of the plastic sheet 1, or on necessary parts, characters, figures, etc.

No. 3 The plastic sheet 1 having the thermally foamable ink 2 printed on its surface as described above is carried onto a vacuum forming machine as shown in FIG. Then, on this vacuum forming machine, it is heated to a required temperature by the heating element 3 and softened. Simultaneously with this softening, the thermally foamable ink 2 foams. At the same time, the air in the cavity 5 in the female mold 4 is sucked through the intake hole 6, and the pressure inside the cavity 5 is reduced. As a result, the plastic sheet 1 comes into close contact with the mold surface of the female mold 4 (Figure 3).
. After cooling, the tightly adhered plastic sheet 1 is removed from the mold to form a product.

The product molded as described above is the same as an ordinary vacuum molded product, but the cross section of the product is shown in FIG. 4, with a foam layer a formed on the surface. This foam layer a has a thickness approximately 10 times that of the printed ink.

Note that the foaming temperature of the thermally foamable ink is about 180° C. or higher. Therefore, it is possible to sufficiently foam the foam at the usual molding temperature for plastic sheets.

In the present invention, as described above, the thermally foamable ink 2 is formed on the surface of the plastic sheet 1 by means of printing (including coating), and is simultaneously foamed by the molding heat of the plastic sheet 1. Or it doesn't take much time. Therefore, even if the foam layer a is formed on the surface of the product, the cost will not increase.

Next, since the foam layer a is formed on the surface of the plastic molded product, the texture of the product is similar to that of a flocked product, giving the product an image of a high-quality product. Therefore, when the surface, inner frame, decorative frame, etc. of a cosmetic case are molded according to the present invention, an unprecedented plastic molded product can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a plastic sheet with thermally foamable ink printed on its surface, FIG. 2.3 is an explanatory diagram of a vacuum forming method, and FIG. 4 is a cross-sectional view showing a part of a molded product. -1...Plastic sheet, 2...Thermoformable ink, 3...Heating element, 4...
...Female O5 type.

Claims (1)

[Claims] A thermofoamable ink is printed on the surface of a thermoplastic plastic sheet, and then the plastic sheet is heated to foam the thermofoamable ink, which is simultaneously molded using a mold to form a foam layer on the surface to obtain a plastic molded product. A manufacturing method for plastic molded products.