JPS5932286B2 - Method for forming opal-like patterns on synthetic resin moldings - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming an opalescent pattern on a synthetic resin molded article by a whitening phenomenon.

For example, when a molded article made of a special synthetic resin such as ABS resin is pressed strongly enough not to be destroyed and then the pressure is released, a white pattern is formed due to a whitening phenomenon. This is because when a molded product is strongly pressed, many tiny cracks occur in the pressed areas, which appear as a white pattern, and this pattern remains as it is at room temperature. The pattern resulting from the above-mentioned whitening phenomenon has a white and gorgeous appearance, and exhibits an opal-like pattern. However, until now, no method has been found to actively apply the whitening phenomenon to synthetic resin moldings to form opalescent patterns. The present invention has been made in order to improve the above-mentioned situation, and its purpose is to positively utilize the whitening phenomenon on synthetic resin molded products to reliably form gorgeous opal-like patterns, and to operate the same. It is an object of the present invention to provide a method for forming an opalescent pattern on a synthetic resin molded product, which can be easily and efficiently performed.

The present invention will be explained below with reference to an embodiment shown in FIG.

In the figure, reference numeral 1 denotes a pressing member formed in a cylindrical shape from a hard material such as metal, and this pressing member descends in the direction of the arrow, and also corresponds to a predetermined pattern on the lower surface 2 of the pressing member 1. A circular convex portion 3a is protruded from the center of the convex portion 3, and two ring-shaped convex portions 3b and 3c concentric with the circular convex portion 3a are protruded from the center of the convex portion 3. However, among these convex portions 3a, 3b, and 3c, the height of the middle link portion 3b is formed to be slightly lower than the others, and as a result, the protruding lengths of the respective convex portions are different. Further, a receiving mold 4 is provided below the pressing member 1, and this receiving mold 4 is formed into a flat plate shape from a hard material such as metal. Recesses 6a, 6b, 6c corresponding to the portions 3a, 3b, 3c are formed, respectively, and the projections 3a, 3b, 3c can be loosely inserted into the recesses 6a, 6b, 6c. Then, a dish-shaped molded product 7 made of a special synthetic resin that has a whitening phenomenon such as ABS resin is placed between the pressing member 1 and the receiving mold 4 at its center.
is set so that it is in the middle, and then the pressing member 1 is lowered. Then, the lower surface of the dish-shaped molded product 7 is received by the receiving mold 4, and the upper surface is pressed by the convex portions 3a, 3b, and 3c of the pressing member 1. Then, the plate-shaped molded product 7 is pressed against the convex portions 3a, 3b, 3c of the pressing member 1.
When pressed within a non-destructive range, the pressed part of the molded product T becomes elastically swollen, and the part slightly enters the recesses 6a, 6b, 6c of the receiving mold 4, and is pressed. There are many small cracks in the part,
This appears as a white pattern 8 on the molded product 7. After pressing within the above range, when the pressing member 1 is raised to release the pressing, the pressed and elastically deformed portion of the molded article 7 returns to its original state, but the white pattern 8 remains as it is. remain. In this way, a white pattern 8 is generated on the part of the molded article 7 pressed by the pressing member 1 due to the whitening phenomenon, and therefore, the convex portion of the presser member 1 is formed on the surface of the molded article 7 as shown in FIG. A ring-shaped white pattern 8aF8bp8c corresponding to 3a, 3b, 3c is generated, and this white pattern 8a, 8b,
8c is white and exhibits a gorgeous opalescent pattern, giving it a beautiful appearance. Furthermore, if the heights of the respective convex portions 3a'3b and 3c are made different, each portion pressed by the convex portions 3ap3b'3c will have a different pressing state, and both convex portions 3a, 3c
3b is high, so it is pressed strongly and the white pattern appears darkly.Conversely, the convex part 3b is low, so it is pressed weakly and the white pattern appears thinly.By making the heights of the convex parts different in this way,
Various patterns can be formed depending on the intensity of the white color.
Further, in the embodiment shown in FIG. 1, the receiving mold 4 is made of a hard material such as metal, and the recess 6 is formed in the upper part of the receiving mold 4, but as shown in FIG. 2, the receiving mold 9 is made of an elastic material such as rubber. If the mold is formed using the above-mentioned method, the upper surface 10 of the receiving mold 9 may be flat because deformation caused by pressing can be absorbed.

In addition, Figures 4 and 5 show another example of a J body with a white pattern, and in Figure 4, a petal-shaped convex part is formed on the pressing surface of the pressing member, and the body is pressed by this convex part. A petal-shaped white pattern 12 is formed on a molded article 11, and in FIG. The pattern 14 is formed, and in this way, various patterns can be formed arbitrarily.

As detailed above, the present invention forms a molded article from a synthetic resin that has a whitening phenomenon, and also forms a convex portion corresponding to a predetermined pattern on the pressing part of a pressing member, and the pressing member presses the molded article. It is characterized in that a pattern is formed on the molded article by a whitening phenomenon by pressing within a non-destructive range. Therefore, when a molded product is pressed by the convex part of the pressing member, minute cracks occur in the pressed part, and a white pattern is formed due to the whitening phenomenon, and the convex part is formed corresponding to a predetermined pattern. This makes it possible to reliably form a gorgeous opalescent pattern on the synthetic resin molded product, and by changing the height of the convex portion, the degree of whiteness can also be changed, making it possible to create various patterns. Not only can it be formed, but it can also be done in a single pressing process.Moreover, a convex part corresponding to a predetermined pattern is formed on the pressing member, and this convex part is pressed against the molded product within a non-destructive range. All you have to do is to do this, so the work can be done very easily and efficiently.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view of one embodiment of the present invention, FIG. 2 is a schematic vertical cross-sectional view of another embodiment of the present invention, and FIG. 3 is a molded product with a pattern formed according to the above embodiment. FIGS. 4 and 5 are plan views of molded articles formed with different patterns, respectively. 1... Pressing member, 3... Convex portion of pressing member, 4 pieces 9... Each receiving mold, 7p11p13...
... Each molded item, 8, 12, 14... Each white pattern.

Claims (1)

[Claims] 1. A molded article is formed from a synthetic resin that exhibits a whitening phenomenon, and a plurality of convex portions corresponding to a predetermined pattern are formed on the press portion, and the above molding is performed using a pressing member in which the protruding lengths of these convex portions are varied. A method for forming an opalescent pattern on a synthetic resin molded article, which comprises pressing the object within a non-destructive range to form a pattern due to a whitening phenomenon on the molded article.