JPH0410690B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing key tops for various devices such as word processors and calculators, and more specifically, the present invention relates to a method for manufacturing key tops for various devices such as word processors and calculators. Concerning methods for forming the body.

(Prior Art) Word processors, calculators, and the like are operated by pressing key tops arranged side by side on a keyboard with fingertips, and these types of key tops are required to meet various quality requirements. In other words, since key tops are pressed and operated many times every day, the identification display pattern formed on the top surface of the key top, which is the pressing operation surface, must have a clear shape, be easy to identify, and be easy to press with a fingertip. . Furthermore, even if used for a long period of time, the paint forming the pattern must not peel off or deteriorate or fade, reducing its distinguishability. Also, the key top is
Since it is easy to get dirty due to the adhesion of hand marks and dust, it is necessary to carefully clean it regularly with a cleaning solution such as alcohol, but the paint that forms the pattern may deteriorate, fade, or peel off due to washing etc. I can't help it. Furthermore, it is desirable that the key top can be formed with good workability and at low cost.

Conventionally, the pattern forming method for this type of key top has been to print chemical paint on the top surface of the key top body using various printing methods such as silk screen printing and hot stamping, as it is easy to work and can be formed at low cost. The method of forming was widely adopted.

(Problem to be Solved by the Invention) However, the pattern formed by this method has low abrasion resistance and chemical resistance of the chemical paint that forms the pattern. There was a problem that the pattern gradually became unclear and its distinguishability decreased. Furthermore, since the patterned surface is smooth and has low surface friction, there are various problems such as the fingertips being unnecessarily slippery when pressing the key tops with the fingertips, so that they are not necessarily highly usable.

Therefore, an object of the present invention is to provide a key top that is highly usable, has excellent durability such as abrasion resistance and chemical resistance, and does not reduce the distinguishability of the pattern even after long-term use. .

(Means for Solving the Problems) For this purpose, the present invention provides ultraviolet curing resin (UV
In addition to protruding a pattern 5 for identification in a desired shape made of a radiation-cured resin 3 such as resin) or electron beam-cured resin (EB resin), a template 6 is provided with unevenness 7 formed on the upper surface of the pattern 5. In the pressed state, radiation is irradiated from above the template 6 to harden the pattern 5, and after curing, the template 6 is removed.

(Function) According to the above configuration, the template 6 is pressed against the uncured liquid pattern 5, and radiation is irradiated in that state to harden it, so that the unevenness 7 of the template 6 is transferred with high precision, resulting in a texture. A key top 10 with good quality can be formed.

Moreover, the template 6 is applied only to the preformed pattern body 5.
Even if the template 6 has a high hardness or a sharp uneven shape, the uncured pattern 5 will gently absorb this pressing force, and the other parts of the key top surface (the pattern) will be hardened. A key top 10 with a good surface finish can be formed without damaging the part (without 5) with a template 6. Further, during curing, the pattern 5 is covered with the template 6 and is isolated from the outside air, so oxygen is blocked during curing, so that the curing is uniformly performed and the pattern 5 is of good quality. can be formed.

(Example) Hereinafter, an example of the present invention will be described along with the drawings.

FIG. 1a shows how a desired pattern is projected from the upper surface of the key top body by silk screen printing. Reference numeral 1 denotes a truncated quadrangular pyramidal key top body made of ABS resin, and a silk screen 2 is abutted on the top surface of the key top, which covers unnecessary parts while leaving a desired pattern.

Reference numeral 3 refers to a radiation-curable resin used as a printing paint, which is colored by mixing a coloring agent of a desired color (for example, a black pigment).A squeegee 4 having a rubber spatula-shaped tip is applied to the top surface of the silk screen 2. By sliding the resin 3 along the grain, the resin 3 is extruded from the grain to form a thick pattern 5 having a desired shape (for example, the shape of the letter "A") (see FIG. 1b).

FIG. 2 shows a template 6, which is a radiation-transparent plate made of transparent glass or synthetic resin, and one surface of which has narrow grooves 7 with a chevron-shaped cross section as irregularities. Many are formed. This template 6
as shown in FIG. When removed from the top surface, the top surface a of the pattern body 5 becomes a mountain-shaped uneven surface (see FIG. 1d).

In this case, the template 6 is pressed against the uncured liquid pattern 5 and in that state it is irradiated with radiation to harden it, so that the unevenness 7 of the template 6 can be transferred with high precision to form a key top with a nice texture. .

Moreover, the template 6 is applied only to the preformed pattern body 5.
The uncured pattern 5
receives this pressing force gently, and the key top 10 with a good surface finish can be formed without damaging other parts of the upper surface of the key top (parts without the pattern 5) with the template 6. Further, during curing, the pattern 5 is covered with the template 6 and isolated from the outside air, so oxygen is blocked during curing, so that the curing is uniform and the pattern 5 is of good quality.
can be formed.

If the template 6 is made of a material that has lower adhesion to the radiation-cured resin 3 than the keytop body 1, the template 6 can be easily peeled off from the upper surface of the pattern body 5.

By the way, the radiation-cured resin 3 forming the pattern 5 is cured by causing chemical reactions such as polymerization reaction, condensation reaction, and cross-linking reaction when irradiated with radiation, and the curing is extremely fast. The pattern body 5 can be cured with extremely good workability.

In addition, the chemical paints conventionally used as pattern-forming paints for this kind of keytops dry by evaporation of the solvent contained in the paint, which not only takes a long time to dry and harden; During curing, drying shrinkage occurs and many fine cracks occur on the surface. Moisture in the air, cleaning liquid, etc. can easily enter into such cracks due to their capillary action, and once the water has entered the cracks, it is difficult to evaporate, so such moisture can cause paint to deteriorate. Discoloration and peeling were accelerated, and the distinguishability of the pattern was significantly reduced with use.

However, the radiation-curable resin 3, which is cured by the chemical reaction mentioned above, has almost no shrinkage due to curing, and therefore almost no cracks occur, so it has the property of not causing deterioration, discoloration, or peeling, and is extremely expensive for a long period of time. Possesses distinctiveness.

Furthermore, the radiation-cured resin 3, which is cured by the chemical reaction described above, has extremely high abrasion resistance and is not easily damaged even when hit by objects, etc., and its structure is extremely dense and does not deteriorate or fade due to aging. It also has good adhesion to synthetic resins, metals, etc. that are commonly used as materials for this type of key top body, and will not peel off.
It also has extremely strong chemical resistance to cleaning solutions such as alcohol solutions.

Since the pattern 5 of this key top 10 is made of the radiation-cured resin 3 having such various excellent properties, its distinctiveness will not deteriorate even after long-term use. In addition, the pattern body 5 is protruded from the upper surface of the key top main body 1 in a slightly thick raised manner, and its upper surface a is an uneven surface to ensure appropriate surface friction, so it feels good to the touch, and the key top 10 When pressing with a fingertip, the fingertip does not slip unnecessarily, and the light entering the uneven upper surface a is moderately diffusely reflected, so it has various excellent usability such as making it easier to see the pattern 5. ing.

Furthermore, if a transparent or semi-transparent material is used as the radiation curing resin 3, the light incident on the uneven upper surface a of the pattern body 5 will be separated by its prism effect and a special visual effect will be obtained. This makes it even easier to identify.

In addition to the template 6 described above, various types of templates may be used to form the upper surface a of the pattern body 5. For example, it is possible to form irregularities of a fine arbitrary shape by processing a textured surface on one side of the plate-shaped body. A template may be used, and the template may be brought into contact with the upper surface of the patterned body 5 to form irregularities of an arbitrary shape on the upper surface of the patterned body 5.

As shown in FIG. 3a, even if the upper surface 21a of the key top main body 21 is recessed in an arc shape for convenience of pressing operation with a fingertip, the recessed upper surface 21
The screen 22 is made into an arc shape to match a,
In addition, the stage 24 also has its tip shaped like an outwardly convex arc so as to match the screen 22.
A desired pattern can be provided on the upper surface 21a of the key top body 21 (see FIG. 3b).

The surface of the main body of the key top on which the pattern is protruded in this way may have a flat surface, a concave arc shape like the upper surface 21a, an outwardly convex arc shape, or a curved shape such as a shape in which only the center portion is recessed. . In addition, when the surface of the main body of the key top on which the pattern is projected is a curved surface, the screen is made of a rigid material such as stainless steel, and is pressed into a curved surface that matches the predetermined curved surface of the main body of the key top. All you have to do is process and mold it into a shape.

(Effects of the Invention) As explained above, the key top manufacturing method according to the present invention includes protruding the identification display pattern 5 made of radiation-cured resin 3 on the surface including at least the top surface of the key top main body 1, and With a template 6 on which unevenness 7 is formed pressed against the upper surface a of the body 5, radiation is irradiated from above the template 6 to harden the patterned body 5, and after curing, the template 6 is removed. As a result, it is possible to manufacture the key top 10 with excellent durability such as abrasion resistance and chemical resistance, which is pleasant to the touch and highly usable, with good workability. In addition, in the present invention, the template 6 is pressed against the uncured liquid pattern 5 and the pattern is cured by irradiating radiation in that state, so that the unevenness 7 of the template 6 is transferred with high precision and the key top 10 has a good texture. can be formed. Moreover, since the mold body 6 is pressed and hardened only on the pre-formed pattern body 5, the uncured pattern body 5 gently absorbs this pressing force, and other parts of the upper surface of the key top (where the pattern body 5 is not A key top with a good surface finish can be formed without damaging the part) with the template 6. Also, during curing, the pattern 5
is covered with the template 6 and is isolated from the outside air, so
Oxygen is blocked during curing, so curing is uniform and uniform, resulting in a high-quality pattern 5.
can be formed.

[Brief explanation of drawings]

The figure shows an embodiment of the present invention.
Figures a, b, c, and d are side and perspective views during key top manufacture, Figure 2 is a perspective view of the template, Figure 3 a,
b is a side view and a perspective view of another embodiment of the invention. DESCRIPTION OF SYMBOLS 1, 21... Key top body, 3... Radiation curing resin, 5... Pattern, 6... Template, 7... Irregularities, 10, 20... Key top, a... Upper surface of pattern.

Claims (1)

[Claims] 1. An identification display pattern 5 made of radiation-cured resin 3 is protruded on the surface including at least the top surface of the key top body 1, and a template 6 on which unevenness 7 is formed is pressed against the top surface a of the pattern 5. In this state, radiation is irradiated from above the template 6 to form the patterned body 5.
A method for producing a key top, characterized in that the template 6 is removed after curing.