JPH0256239B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for integrally forming reliefs such as letters, symbols, or figures on the surface of an object to be treated using ultraviolet rays or electron beam curable resin. , symbols, and shapes.

Embodiments of the present invention will be described below based on the drawings.

1 and 4, first, an ultraviolet or electron beam curable resin is applied to the surface of an object to be treated 1 to form a coating film 2, and then the coating film 2 is left in an uncured state. A shadow mask 3 is superimposed on the surface of the membrane 2. As shown in FIG. 3, the shadow mask 3 is made of a transparent thin plate that transmits the rays or electron beams, and the areas 5 other than the pattern 4 are colored to represent a pattern 4 of transparent embossed characters, symbols, or figures on its inner surface. It is made opaque. This shadow mask 3 is superimposed on the surface of the uncured coating film 2, and then irradiated with a cylindrical beam or an electron beam. Then, the coating film 2 has a portion 4 that matches the pattern 4 of the shadow mask 3 through which ultraviolet rays or electron beams are transmitted.
Only portion a is cured, and portion 5a corresponding to the other colored and opaque portion 5 remains uncured. Thereafter, by peeling off the shadow mask 3 and washing off the uncured portion 5a of the coating film 2 with a solvent, the desired relief 6 of characters, symbols, figures, etc. is integrally formed on the surface of the object 1 to be treated, as shown in FIG. is formed.

A specific example of the object to be processed 1 is, for example, an electric shaver product as shown in FIG. 6, and the case surface of this product is made of ABS resin. On this surface, the English letters "ABC" are made of UV-curable resin such as photopolymerizable resin mainly composed of acrylic oligomers with acryloyl groups in the molecule.
and the relief 6 of "PUSH" are integrally formed by the method described above.

The method for forming the desired pattern 4 of embossed characters, symbols or figures on the shadow mask 3 is as follows:
As an alternative to the above method, there is a method of cutting out and forming a pattern 4 on a shadow mask 3 made of an opaque plate as shown in FIG. Although this does not occur, if the letters "A" and "B" shown in FIG. 9 are cut out and formed, the font will have the shaded area 7 in the figure removed, which is of no use. In this regard, according to the method of the present invention, it is possible to represent various characters, symbols, figures, etc. in addition to "A" and "B".

It is preferable for the shadow mask 3 to mask the coating film 2 in a polymerized state in which the side surface 3a on which the pattern 4 is formed is in contact with the coating film 2, in order to clearly show the outline of the embossed characters, symbols, or figures.
That is, as shown in FIG.
When masking is done so that the surface 3a on the side where the pattern 4 is formed and the surface 3b on the opposite side are in contact with the surface of the coating film 2, the ultraviolet rays or electron beams L incident on the shadow mask 3 from the transparent pattern 4 part are This is because the refracted light beam is refracted into the lower layer A of the colored opaque area 5, and the outer part of the coating film 2 other than the part 4a that matches the pattern is also hardened, which tends to create an embossment 6 with an unclear outline. be.
However, when the surface 3a on the pattern formation side of the shadow mask 3 is in a polymerized state in contact with the coating film 2 as described above, this problem does not occur, and the relief 6 hardens along the outline of the pattern 4 and has excellent density. You can get a similar image.

As explained above, in the relief forming method of the present invention, a coating film 2 is formed by applying an ultraviolet ray or electron beam curable resin to the surface of an object to be treated 1, and the surface of the coating film 2 is left in an uncured state. Overlay shadow mask 3 on the area 4 that matches pattern 4 of shadow mask 3.
Since the relief 6 is formed by hardening only the portion a by ultraviolet rays or electron beam irradiation and removing the unhardened portion 5a with a solvent, it is easy to form the relief 6 such as letters, symbols, or figures on the surface of the object 1 to be treated. The ultraviolet ray/electron beam curable resin cures in an extremely short time, improving productivity. In addition, the surface hardness of the relief can be increased, the abrasion resistance is excellent, and no heat is required to harden the relief, so the relief 6 can be formed satisfactorily even on the object 1 to be treated for which heating is inappropriate.

In particular, the shadow mask 3 used in the method of the present invention is composed of a transparent thin plate, and the pattern 4 of transparent embossed characters, symbols, figures, etc. formed on this plate is made by coloring areas 5 other than the pattern 4 to make them opaque. Since the method is made to obtain a pattern by cutting out a pattern on an opaque shadow mask, a wide variety of patterns can be obtained, and a wide variety of reliefs can be produced, compared to a method in which patterns are cut out and formed on an opaque shadow mask. Furthermore, the method of the present invention has the advantage that the device can be made smaller, is relatively simple, requires only a small area of equipment, and has low equipment costs.

[Brief explanation of the drawing]

1 to 6 show examples of the present invention, and FIG. 1 is a perspective view showing a state in which a shadow mask is overlaid on a coating film formed on the surface of an object to be treated;
Figure 2 is a perspective view showing the state in which relief is formed on the surface of the object to be processed, Figure 3 is a partial perspective view of the shadow mask, Figure 4 is a cross-sectional view showing the state of ultraviolet irradiation, and Figure 5 is the formation of relief. FIG. 6 is a cross-sectional view of the object to be treated showing the state, and is a perspective view of the electric shaver with relief. FIG. 7 is a sectional view showing another example of the usage state of the shadow mask. FIG. 8 is a perspective view showing an undesirable shadow mask, and FIG. 9 is a plan view illustrating embossed characters in that case. 1...Object to be treated, 2...Coating film, 3...Shadow mask, 4...Pattern, 5...Colored opaque area, 6...Relief.

Claims (1)

[Claims] 1. A step of applying an ultraviolet or electron beam curable resin to the surface of the object to be treated 1 to form a coating film 2, and applying a transparent thin plate to the surface of the coating film 2 in an uncured state. A process of overlapping a shadow mask 3 in which parts 5 other than the pattern 4 are colored and made opaque so that only the pattern 4 is transparent, and the pattern 4 of the coating film 2 is irradiated with ultraviolet rays or electron beams on the surface of this shadow mask 3. and a step of removing the shadow mask 3 after the coating film 2 is cured and cleaning and removing the uncured portion 5a of the coating film 2 that matches the colored opaque area 5 of the shadow mask 3 with a solvent. A relief forming method characterized by: 2. The relief forming method according to claim 1, wherein the shadow masks 3 are overlapped with each other so that the surface 3a on which the pattern 4 is formed is in contact with the coating film 2.