JPH02260334A - Manufacture of key top - Google Patents

Abstract

PURPOSE:To provide a uniformly lighted key top having a rugged pattern excellent in appearance by laminating a light-permeable colored coating material, a light-shielding film, and a pattern coating material successively from the bottom on a transparent base material followed by irradiating with YAG laser beams. CONSTITUTION:On a base material 4 having a flat surface, a coat of an orange two-liquid hardening type coating material (acryl or urethane) is applied to form a ground layer 9. A coat of a black two-liquid hardening type coating material (acryl or urethane) is applied on the ground layer 9 to form an intermediate layer 10. A gray pattern coating material is applied on the intermediate layer 10 to form a pattern layer 11 having a crepe pattern on the surface. Then, irradiation with YAG laser beams 6 is conducted to remove only the parts corresponding to both display parts 2, 3 from the pattern layer 11 and the intermediate layer 10. At that time, by selecting the grain size and distributed density of polymer shells 13a, 13b dispersed on the pattern layer 11 of the top layer, rugged patterns excellent in appearance such as crepe pattern can be formed on the surface of a key top 1.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing key tops provided in in-vehicle switches, various input devices, etc., and particularly relates to an illuminated key top whose display section illuminates at night, etc. Concerning a top manufacturing method.

[Conventional technology]

Various methods are known for manufacturing key tops, and among them, a method called a laser processing method is widely used as a method for manufacturing key tops of the type in which the display section is illuminated.

Fig. 4 is a plan view of a key top manufactured by the conventional laser processing method, Fig. 5 is a cross-sectional view thereof, and Figs. 6(a) to (
d) is a process diagram showing the manufacturing method.

In FIGS. 4 and 5, 1 generally indicates a key top, and the top surface of the key top 1 has a first display section 2 and a second display section 3 that are visible from the outside. It is formed. The key top 1 includes a base material 4 molded from a transparent synthetic resin such as acrylic resin, and a white base rf made of a light-transmitting colored paint provided on the surface of the base material 4.
i5, and a black outer layer 6 made of light-shielding paint provided on the surface of the base layer 5 except for a part, and the first and second display portions 2.3 are formed by the black outer layer 6. It is composed of a white base N5 exposed in G. Therefore, in a bright place such as during the daytime, by visually observing the difference in color between the base layer 5 and the outer layer 6 using external light, the first and second display sections 2 and 3 can be displayed as f'! I can recognize it. In addition, at night or in a dark place such as in a tunnel, the lamp 7 placed inside the key top 1 is turned on, and this light passes only through the base material 4 and the base layer 5 and reaches the outside. The first and second display sections 2. are illuminated in a dark place.
3 h′! I can endure words.

When manufacturing the key top 1 configured as described above, 1. First, as shown in FIG. 6(a), a base material 4 of a desired shape is formed using acrylic resin or the like, and then a base layer 5 is coated on the surface of the base material 4, as shown in FIG. 6(b). Further, as shown in FIG. 5C, an outer shape 1iI6 is applied onto the base eyebrow 5 by means of painting, sputtering, vapor deposition, or the like. Furthermore, as shown in FIG. 2(d), a part of the outer shape layer 6 is irradiated with a YAG laser beam 8, and the outer shape rrB6 is irradiated with this laser light 8 only in the portions corresponding to the first and second display sections 2 and 3. By removing it, the key top 1 shown in FIG. 4 is manufactured. In addition, on the entire outside of the key top,
Transparent node coat, - (not shown) as required! ! ! It is deposited by means such as coating, sputtering, or vapor deposition.

[Problem to be solved by the invention]

By the way, the surface condition required for this type of key top is not necessarily a flat surface, but also a key top with a roughened surface such as a satin-finished surface. When manufacturing patterned key tops, conventionally, in the process shown in FIG. 6(a) described above, an uneven surface corresponding to the satin pattern is formed on the surface of the base material 4 in advance, and then this base material 4 is used. A satin-patterned key top was obtained by going through the same steps as shown in FIGS. 6(b) to 6(d).

However, in this case, since the uneven shape of the surface of the base material 4 is reproduced on the surface of the outer layer 6 via the base layer 5, the reproducibility of the uneven surface is poor, and it is difficult to obtain a satin pattern with excellent appearance. It was difficult to obtain.

Also, base 1! Since the unevenness of the base material 4 is reproduced on the surface of f5, the thickness of the base layer 5 through which the light emitted from the lamp 7 passes becomes uneven, causing unevenness in the illumination color of the display section 2゜3. There was also some pressure.

The present invention has been made in view of the above-mentioned circumstances, and its object is to provide a key top that can realize a concavo-convex pattern with a immersed appearance and is free from uneven illumination.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a method for manufacturing a key top in which a display portion formed on the front surface is illuminated by light from the back side. On the molded base material, a light-transmissive colored paint, a light-shielding film, and a light-transparent patterned paint containing fine particles with a particle size of 15 μm or more are laminated in order from the bottom, and then the patterned paint and the precious metal are laminated in order from the bottom. This method is characterized in that a portion of the light film is removed using a YAG laser beam to expose the colored paint.

[Effect]

As described above, when a light-transmitting colored paint, a light-shielding film, and a patterned paint are applied in order from the bottom to nr/1 on a transparent base material, the key An uneven pattern such as a satin pattern is formed on the surface of the top. Here, although the patterned paint contains a large amount of light-transmitting substances and has poor light-shielding properties, since there is a light-shielding film underneath it,
There is no light leakage when lighting at night. In addition, since the light-shielding film has the property of being easily blown away by YAG laser light,
By irradiating the laser beam, the pattern paint and the light-shielding film are removed cleanly, the colored paint is exposed to the light transmitted through it, and color unevenness in the illuminated color is eliminated.

〔Example〕

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

FIG. 1 is a sectional view of a key top according to an embodiment of the present invention, and parts corresponding to those in FIG. 5 are designated by the same reference numerals. As shown in the figure, the key top 1 is made of a base material 4 molded from a transparent synthetic resin such as acrylic resin, and a light-transmitting colored paint provided on the surface of the base material 4, for example, in an orange color. a base layer 9, an intermediate layer 10 made of a black light-shielding paint or a metal film such as chromium, which is provided on the surface of the base layer 9 except for a part; The first and second display portions 2.
3 is constituted by an orange base W19 exposed within the gray pattern layer 1).

The pattern layer 1) is, for example, as shown in FIG. 2(a),
A pattern paint in which a polymer shell 13a containing a colored pigment is dispersed in a colorless and transparent binder resin 12a, and a pattern paint in which a colored transparent binder resin 12b containing a colored pigment is dispersed, as shown in FIG. A pattern paint in which a polymer shell 13b is dispersed, or a pattern paint in which a polymer shell 13a containing a colored pigment is dispersed in a colored transparent binder resin 12b containing a colored pigment, as shown in FIG. 2(C). consisting of polymer shells 13a, 13b
An uneven pattern such as a satin pattern is formed on the surface depending on the particle size and density. Binder resin 12a.

As the material 12b, an acrylic or urethane resin is used, and as the polymer shells 13a and 13b, glass beads, nylon beads, mica, or the like having a particle size of 15 μm or more (preferably 20 to 100 μm) are used.

In the key top 1 configured as described above, in a bright place such as during the day, the gray satin pattern can be detected by visually observing the difference in color between the base layer 9 and the pattern layer 1) using external light. You can see the display section 2.3 shown in orange. On the other hand, at night or in a dark place such as in a tunnel, the lamp 7 placed inside the key top 1 is turned on, and the display unit 2 .3 is illuminated in orange.

In this case, although the uppermost pattern layer 1) contains a large amount of light-transmitting material as described above and has no light-shielding power, the intermediate layer 10 below it has a light-shielding power, so the light from the lamps is transmitted to the display area. Other than 2 and 3, it will definitely be shut off.

Next, a method of manufacturing the key top 1 constructed as described above will be explained with reference to FIG.

First, as shown in FIG. 3(a), a base layer 9 is formed by applying an orange two-component curing paint (acrylic or urethane type) onto a base material 4 having a flat surface. This base layer 9 transmits light and has the property of being difficult to absorb YAG laser light, which will be described later. Next, the same figure (b
), a black two-component curing paint (acrylic or urethane type) is painted on the base layer 9, or a metal film such as chromium is sputtered to form an intermediate layer 7! ! 10
form. This intermediate layer 1o blocks light and
It has the property of easily absorbing YAG laser light. Next, as shown in FIG. 2(c), on top of the intermediate 71) 0,
) to (C) are applied with a gray pattern paint to form a pattern N1) with a satin pattern on the surface. This pattern layer 1) exhibits light transmittance and has the property of absorbing YAG laser light less easily than the intermediate layer lo below it.

Thereafter, as shown in FIG. 3(d), a part of the pattern fill is irradiated with a YAG laser beam 8, and the laser beam 8 causes the pattern layer 1) and the intermediate layer 10 to correspond to the image display area 2°3. By removing only the key top 1 shown in Figure 1,
is manufactured. In this case, although there is no big difference in the absorption rate of the YAG laser beam 8 between the pattern JWII on the top layer and the base layer 9 on the bottom layer, both j! ! 9.1) YAG in between
Since there is an intermediate 1) 0 that easily absorbs the laser beam 8, Y
Pattern of the part irradiated with AG laser beam 8 1) 1 and middle J
The ilO was removed cleanly and the gray pattern layer 1 of the satin pattern was removed.
) The orange base layer 9 is exposed inside.

In the above embodiment, by selecting the particle size and distribution density of the polymer shells 13a and 13b (m particles) dispersed in the uppermost pattern layer 1), the surface of the key top 1 has an appearance. An excellent uneven pattern such as a satin finish pattern can be applied. Furthermore, since the surfaces of the intermediate layer 10 and the base layer 9 except for the pattern Jllll are flat, the thickness of the base layer 9 through which the light from the lamp 7 passes is made uniform, and uneven illumination can be prevented.

Furthermore, a YAG laser beam 8 is applied between the pattern 71) 1 and the base layer 9.
Since the intermediate JILO, which is easy to fly, is provided, the exterior color and display color can be set to colors other than black and white, and the display quality can be improved.

It should be noted that the shapes and numbers of the display sections 2 and 3 are not limited to those in the above embodiments.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to realize an uneven pattern that is excellent in appearance and to prevent uneven illumination, and its practical value is high.

The value is high.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a key top according to an embodiment of the present invention;
Figures 2 (a), (b), and (c) are configuration diagrams of the pattern layer used in the key top, Figure 3 is a manufacturing process diagram of the key top, and Figure 4 is a diagram of the key top according to the conventional example. FIG. 5 is a plan view, FIG. 5 is a sectional view of the same, and FIG. 6 is a manufacturing process diagram of the key top. １・・・・・・・・・Key top, ２・・・・・・・・・
・First display section, 3... Second display section,
4...Base material, 8. Old... YAG laser beam, 9... Base layer, 10. Old...
...Middle layer, 1)... Pattern layer, 12a,
12b...Binder resin, 13a, 13
b...Polymer shell (fine particles). Fig. 1 Fig. 2 Key top display part base material lamp base layer intermediate layer pattern layer Fig. 3 Fig. 4 Fig. 5 Fig. 6

Claims (3)

[Claims] (1) In a method of manufacturing a key top in which a display part formed on the front surface is illuminated by light from the back side, the key top is formed on a base material molded from a colorless transparent or colored transparent synthetic resin. , a light-transmitting colored paint, a light-shielding film, and a particle size of 15
A light-transmitting patterned paint containing fine particles of μm or larger is laminated in order from the bottom, and then a portion of the patterned paint and light-shielding film is removed using a YAG laser beam to expose the colored paint. Features: Keycap manufacturing method. (2) The method for manufacturing a key top according to claim (1), wherein the light-shielding film is a black light-shielding paint. (3) The method of manufacturing a key top according to claim (1), wherein the light shielding film is a metal film.