JPH05225850A - Manufacture of key top - Google Patents

Abstract

PURPOSE:To manufacture a key top excellent in use property, etc., by hardening a pattern with radiation after projection-molding the pattern with radiation- hardening resin, which contains fine powder of glass or the like, on the surface when forming an identification and indication pattern such as a graphic, a character, etc., on the key top. CONSTITUTION:A needless part is covered with a silk screen 12, leading an identification and indication pattern 15 such as a desired graphic, a character, etc., on the topside of a head-cut pyramidal key top 11 made of synthetic resin. An identification and indication pattern 15 such as a desired graphic, character, etc., is formed on the topside of the key top 11 by pressing and sliding radiation curing resin 13, which is colored with a desired colorant and contains fine powder 16 such as glass beads, etc., against the topside of the key top 11 with the use of a squeeze 14, the top of which is made spatulate out of rubber. Then the pattern 15 formed by the resin 13 is hardened by applying thereto radiation from a radiation generating source 8. The key top, which has excellent corrosion resistance and chemical resistance and is high in use property, can be provided by the mixing-in of fine powder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a key top for various devices such as a word processor and a calculator, and more particularly to a method for forming a desired shape pattern such as letters and figures on the surface of the key top body. Then, a pattern body made of a radiation curable resin is projected on the surface of the key top body, and irregularities are formed by fine particles on the upper surface of the pattern body.

[0002]

2. Description of the Related Art A word processor, a calculator, or the like is operated by pressing a key top arranged in parallel on a keyboard with a fingertip, and this kind of key top is required to have various quality requirements. That is, since the key top is pressed many times every day, the identification display pattern formed on the upper surface of the key top, which is the pressing operation surface, has a clear shape and is easy to identify, and it is easy to press with the fingertip. There must be. In addition, even if it is used for a long period of time, the paint that forms the pattern should not come off or deteriorate and discolor, thereby reducing its distinguishability. Also, since the key tops are liable to get dirty with dirt and dust, it is necessary to carefully wipe the key tops with a cleaning solution such as an alcohol solution, but the paint that forms the pattern deteriorates and fades due to cleaning. Do not drop or peel off. Furthermore, the key top is
What can be formed with good workability at low cost is desirable. Conventionally, this type of key top pattern forming method has good workability and can be formed at low cost. Therefore, a chemical paint is printed on the upper surface of the key top body by various printing methods such as silk screen printing and hot stamping. The method of forming by this was widely adopted.

[0003]

However, since the pattern formed by such a method has low abrasion resistance and chemical resistance of the chemical paint forming the pattern, it may be used or wiped with alcohol or the like. There is a drawback that the pattern gradually becomes unclear and its distinguishability deteriorates. Further, since the pattern surface is smooth and the surface friction is small, there are various drawbacks such as the fingertip being unnecessarily slippery when pressing the key top with the fingertip, and thus the usability is not necessarily high.
Therefore, an object of the present invention is to provide a key top which has high usability and is excellent in durability such as abrasion resistance and chemical resistance, and whose pattern distinctiveness does not deteriorate even after long-term use. To do.

[0004]

To this end, the present invention comprises a radiation curing resin such as an ultraviolet curing resin (UV resin) or an electron beam curing resin (EB resin) on the surface including at least the upper surface of the keytop body. Pattern 1 for identification display of desired shape
5 are projected, and the fine particles 1 are provided on the upper surface of the pattern 15.
6 is arranged, and the pattern 15 is irradiated with radiation to generate the pattern 1.
5 is to be cured.

[0005]

According to the above construction, the radiation curable resin 13 can form the pattern body 15 having many excellent characteristics with good texture and distinctiveness. Moreover, in this case, since the fine particles 16 are arranged before curing, various patterns of dispersion amount can be manufactured for each pattern 15.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 (a) shows that a desired pattern is projected on the upper surface of the key top body by silk screen printing, and 11 is a truncated quadrangular pyramid key top body made of ABS resin. On the upper surface, a silk screen 12 is in contact with which the desired pattern is left and which covers the unnecessary portion. 13 is a radiation curable resin as a printing paint,
A squeegee 14 having a spatula-shaped rubber tip made of a colorant (for example, a black pigment) of a desired color mixed therein is slid along the upper surface of the silk screen 12 to remove the resin 3. The pattern body 15 having a desired shape (for example, the shape of the letter "A") is extruded from the silk grain to project in a thick wall. Next, radiation is applied from above to cure the pattern 15 (see FIGS. 1B and 1C). Fine particles 16 such as glass beads or urethane beads having a particle diameter of about 10 to 30 μm are mixed in advance in the resin 13, and the fine particles 16 make the surface 6 of the pattern body 15 uneven. In this case, since the fine particles 16 are arranged before curing, each pattern 15
Various dispersion amounts can be manufactured for each. By mixing the fine particles 16 in the resin 13 in this way, if the surface of the pattern body 15 is made uneven, it is possible to secure appropriate surface friction. When the fine particles 16 are mixed in the resin 13 as described above, the opening of the screen 12 must be of a size that allows passage of the fine particles 16 having a predetermined particle size. The present invention can be modified in various ways. For example, as a method of mixing the fine particles 16 with resin, after a desired pattern is projected on the surface of the keytop main body,
The fine particles 16 may be mixed into the pattern body by spraying the fine particles 16 on the pattern body with a spraying machine or the like. Further, the shape of the key top body may be a truncated quadrangular pyramid shape, a truncated cone shape, a truncated polygonal pyramid shape, a disc shape, or the like. It may be formed also on the side surface of the top body, as long as it is formed on the surface including at least the upper surface of the keytop body. By the way, the radiation curable resin 13 forming the pattern body 15 is a resin which undergoes a chemical reaction such as a polymerization reaction, a condensation reaction or a cross-linking reaction upon irradiation with radiation to be cured, and the curing is extremely fast. The pattern 15 can be cured with extremely good workability. In addition, the chemical paint that has been conventionally used as a paint for forming patterns of this kind of key top dries when the solvent contained in the paint evaporates, and not only does it take a long time to dry and cure. During curing, drying shrinkage occurs, and many fine cracks occur on the surface. In such a crack,
Moisture in the air, cleaning liquid for wiping, etc. easily enter due to its capillary action, and water etc. once entering the cracks is difficult to evaporate, so such moisture etc. accelerates deterioration and fading of paint However, there is a drawback that the distinctiveness of the pattern is remarkably lowered during use. However, the radiation curable resin 13 that cures by causing the above-mentioned chemical reaction has almost no shrinkage associated with curing, and therefore cracks hardly occur. Possess sex.
Further, the radiation-curable resin 13 which is cured by the above-mentioned chemical reaction
Has extremely high abrasion resistance and is not easily scratched by objects, etc., and its structure is extremely dense and does not deteriorate or discolor due to aging, and is generally used as a material for this type of keytop body. It also has good adhesion to synthetic resins and metals, and does not peel off. Further, it has a very strong chemical resistance against a cleaning liquid such as an alcohol liquid. This key top pattern 15
Is formed of the radiation curable resin 13 having various excellent properties, and therefore, its distinguishability does not deteriorate even after long-term use. Further, the pattern body 15 is provided on the upper surface of the key top body 11 so as to project in a slightly thicker wall, and the upper surface thereof becomes an uneven surface to ensure an appropriate surface friction. Since the fingertip does not unnecessarily slip when pressing with the fingertip, and the light is appropriately diffusely reflected upon entering the uneven top surface, it has various excellent usability such as easy viewing of the pattern body 15. There is. If a transparent or translucent resin is used as the radiation curable resin 13, the light incident on the uneven upper surface of the pattern body 15 is dispersed by the prism effect and a special visual effect is obtained. It will be easier to identify.

[0007]

As described above, in the method of manufacturing a keytop according to the present invention, the identification display pattern body 15 made of the radiation curable resin 13 is provided on the surface including at least the upper surface of the keytop body 11, and Since the fine particles 16 are arranged on the upper surface of the pattern body 15 and the pattern body 15 is irradiated with radiation to cure the pattern body 15, it has excellent durability such as abrasion resistance and chemical resistance, and A highly usable key top can be formed with good workability. Moreover, according to the present invention, since the fine particles 16 are arranged before curing, it is possible to manufacture various patterns 15 with various dispersion amounts.

[Brief description of drawings]

FIG. 1 is a side view and a perspective view during manufacturing of a keytop.

[Explanation of symbols]

 11 key top body 13 radiation curable resin 15 pattern

Claims (1)

[Claims] 1. A pattern body 15 for identification display made of a radiation curable resin 13 is projected on the surface including at least the upper surface of the keytop body 11, and fine particles 16 are arranged on the upper surface of the pattern body 15 to form the pattern. A method of manufacturing a key top, characterized in that the pattern 15 is cured by irradiating the body 15 with radiation.