JP2625539B2 - Key Top Manufacturing Method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a method of manufacturing a key top used for a keyboard of a personal computer or the like, and more particularly, to a method of forming a desired display portion by a printing method called pad printing. The present invention relates to a method for manufacturing a key top.

[Conventional technology]

Usually, characters, figures, symbols, and the like are displayed on the upper surface of this type of key top, but the operator presses the upper surface of the key top with a finger to operate the key top. Therefore, there is a problem that it easily disappears. Therefore, there has been known a key top in which the display unit is covered with an overcoat layer for the purpose of a display unit having high wear resistance.

As a method of overcoating the key top, a spray method of spraying an ultraviolet curable resin on the upper surface of the key top on which the display unit is printed, a pad printing method of transferring the ultraviolet curable resin to the display unit by using a stamping member such as silicon rubber, or the like. However, the former spray method has drawbacks in yield and finished appearance, so the pad printing method of the latter has attracted attention in recent years, and is particularly widely used in the case of small-lot production of many types.

FIGS. 7 and 8 illustrate a conventional pad printing method proposed by the present applicant in Japanese Patent Application Laid-Open No. 63-4509, and FIGS. 7A to 7G show the transfer of an ultraviolet curable resin. FIG. 8 is a plan view showing a key top after the transfer step is completed.

In FIG. 8, reference numeral 6 denotes a key top main body, and a desired display portion (for example, an alphabet A shown in the drawing) is formed on the top surface of the key top main body 6 by pad printing. Is overcoated by pad printing with an ultraviolet curable resin 3 of the same shape. The overcoat layer forming step will be described with reference to FIG. 7. First, the ultraviolet curing resin 3 is filled in the etching groove of the etching plate 1 shown in FIG. 7A as shown in FIG. This etching groove 2 has the same shape as the display section of the key top body 6 described above. Next, FIG.
As shown in (D), the stamping member 5 made of silicone rubber is brought into contact with the ultraviolet curing resin 3, and the ultraviolet curing resin 3 is adsorbed on the lower surface of the stamping member 5. Next, as shown in FIG. 2E, a key top body 6 having a display section 4 already formed by pad printing is disposed immediately below the stamping member 5, and the stamping member 5 is pressed against the display section 4 to display the image. The ultraviolet curing resin 3 is transferred and formed on the upper surface of the portion 4. Finally, as shown in FIG. 8G, the ultraviolet curing resin 3 is irradiated with ultraviolet rays from an ultraviolet lamp 7 to obtain the key top body 6 shown in FIG.

[Problems to be solved by the invention]

By the way, in the above-mentioned conventional manufacturing method, the curvature of the lower surface of the sealing member 5 is set to be sufficiently smaller than the curvature of the top surface of the key top body 6, thereby pressing the sealing member 5 against the key top body 6. At this time, the entrapment of air in the [step of FIG. 7 (E)] was prevented. However, in this case, when the stamping member 5 is separated from the top surface of the key top body 6 after the transfer (step of FIG. 7 (F)), the ultraviolet-curing resin 3 is pulled by the stamping member 5, and There is a problem that wrinkles are easily generated in the coat layer (ultraviolet curable resin 3). Since the wrinkles become more remarkable as the transfer area of the ultraviolet curable resin 3 increases, for example, when the ultraviolet curable resin 3 is formed on the entire top surface of the key top body 6 including the display section 4, the film of the overcoat layer is formed. There is a problem that the thickness becomes non-uniform and the quality is remarkably reduced.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a high-quality key top in which an overcoat layer can be formed with a uniform thickness on the top surface of the key top body.

[Means for solving the problem]

In order to achieve the above object, the present invention relates to a key top manufacturing method for printing a display on a key top main body, and then pressing a stamping member made of a soft material onto the display surface to transfer and form an overcoat layer. The overcoat layer is formed by inclining the axis of the main body with respect to the pressing direction of the stamping member, and displacing the stamping member with respect to the key top body and transferring the stamp plural times, thereby forming the overcoat layer. It is.

[Action]

According to the manufacturing method of the key top according to the present invention, the axis of the key top body is inclined with respect to the pressing direction of the sealing member. Is prevented. In addition, since the overcoat layer is formed by a plurality of transfers and the transfer is performed by shifting the relative position of the stamping member and the key top body, the coating resin generated when the sealing member is separated from the key top body is formed. Are dispersed, and an overcoat layer of a uniform film is obtained.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a stamping member and a key top body used in an embodiment of the present invention. As shown in FIG.
A curved surface 8a is formed on the lower surface of the stamping member 8 made of a soft material such as silicon rubber, and the top surface of the key top body 9 is formed.
9a is also curved. The curved surface 8a of the stamping member 8 is formed to be slightly wider than the top surface 9a of the key top body 9, and as shown in FIG. 2, the radius of curvature of the curved surface 8a and the top surface 9a is R ₁ = In the case of this embodiment, 18 mm, R ₂ = 22 mm, the curvature of the curved surface 8 a of the sealing member 8 is set so as to be very close to the curvature of the top surface 9 a of the key top body 9.

Next, the top surface of the key top body 9 is
The step of forming an overcoat layer on 9a will be described.

First, a desired display (A in this embodiment, an alphabet A) 10 is printed on the top surface 9a of the key top body 9.
This step is performed by a known pad printing method, that is, a printing method in which the ink filled in the etching groove is transferred to the top surface 9a via a soft stamping member (not shown).

Next, an overcoat layer is formed on the entire top surface 9a of the key top body 9 on which the display unit 10 is printed by using the stamping member 8. In this case, the axis α of the stamping member 8 and the axis β of the key top body 9 are inclined at a predetermined angle θ (θ = 6 ° in the present embodiment) as shown in FIG. As shown in a), the offset is offset to the left side of the key top body 9, and the overcoat layer is pad-printed in this state.

4 and 5 are explanatory views of the pad printing process as viewed from the front and right sides of the key top body 9, respectively. First, an ultraviolet-curing resin is applied to the curved surface 8a of the stamping member 8 using an etching plate not shown. After adsorbing 11,
The stamping member 8 is lowered in the axial direction as shown in FIGS. 4 and 5 (a), and the curved surface 8a is pressed against the top surface 9a of the key top body 9 as shown in FIGS. 4 and 5 (b). At this time, the key top body 9 is arranged so that the top surface 9a is inclined with respect to the curved surface 8a, so that the curved surface 8a moves from the rear to the front (right to left in FIG. 3) on the top surface 9a. Abut to rub. Therefore, even if the curvature of the curved surface 8a is made closer to the top surface 9a as in the present embodiment, there is almost no risk that air will be trapped between the ultraviolet curable resin 11 and the top surface 9a. Thereafter, the sealing member 8 is raised as shown in FIGS.
A predetermined thickness, for example, 7 μm, over the entire area of the top surface 9a including the display unit 10.
Transfer to the extent. At this time, the curved surface 8a having a smaller curvature than the top surface 9a is sequentially separated from the left and right ends of FIG. 4 (c) toward the center, but in the present embodiment, the curvature of the curved surface 8a is changed to the top surface. Since the curvature is close to the curvature of 9a, the amount of the ultraviolet curable resin 11 being pulled to the center of the curved surface 8a which is finally separated from the top surface 9a is reduced, and the generation of wrinkles due to this is almost eliminated. The slight wrinkles generated in this way are offset from the center of the sealing member 8 to the left with respect to the key top body 9 as shown in FIG. It is located on the left side.

When the ultraviolet curing resin 11 is transferred onto the top surface 9a of the key top body 9 as described above, the center of the stamping member 8 is offset to the right of the key top body 9 as shown in FIG. Then, pad printing similar to that of the first transfer is repeated to perform the second transfer. As a result, an overcoat layer having a thickness of about 14 μm is formed, but a slight wrinkle generated in the ultraviolet curable resin 11 in the second transfer is located on the right side of the center of the top surface 9a.

Thereafter, as shown in FIG. 6 (c), the center of the stamping member 8 is made to coincide with the center of the top surface 9a, and in this state, the same pad printing as the first and second times is repeated, and finally, To
An overcoat layer having a thickness of about 20 μm is formed. On this occasion,
The wrinkles generated in the first and second steps are the third wrinkles.
The overcoat layer having a uniform thickness is formed by the curved portion 8a of the stamping member 8 pressed against the top surface 9a in the third step.

Finally, the ultraviolet curable resin 11 is cured by using an ultraviolet lamp (not shown) to obtain the key top body 9 having the overcoat layer formed on the entire top surface 9a including the display section 10.

As described above, according to the above embodiment, both the display section 10 and the overcoat layer (ultraviolet curable resin 11) can be formed by the pad printing method, so that the yield and quality of the material can be improved. In addition, since the overcoat layer can be formed as a uniform film over the entire top surface of the key top body 9, a high-quality display unit having high wear resistance can be provided.

〔The invention's effect〕

As described above, according to the present invention, the overcoat layer can be formed on the entire top surface of the key top body while suppressing the entrainment of air and wrinkles, so that a high quality key top can be provided at low cost.

[Brief description of the drawings]

1 to 6 illustrate an embodiment of the present invention. FIG. 1 is a perspective view of a stamping member and a key top body, and FIG.
FIG. 3 is an explanatory view showing the curvature of the stamping member and the key top body, FIG. 3 is an explanatory view showing the inclined state of the stamping member and the key top body, and FIGS. 4, 5, and 6 are pad printing steps of the overcoat layer. FIG. 7 is an explanatory view showing a conventional pad printing process of an overcoat layer, and FIG. 8 is a plan view of a key top body. 8 ... stamping member, 8a ... curved surface, 9 ... key top body, 9a ... top surface, 10 ... display unit, 11 ... ultraviolet curable resin.

Claims (1)

(57) [Claims] 2. A method for manufacturing a key top, comprising: printing a display portion on a key top body; and pressing a stamping member made of a soft material onto the display surface to transfer and form an overcoat layer, wherein the axis of the key top body is aligned with the stamping member. Forming the overcoat layer by inclining the stamping member with respect to the pressing direction and transferring the stamping member a plurality of times while displacing the stamping member with respect to the keytop main body.