JPH043755B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a method for manufacturing a synthetic resin molded product with characters and symbols, and its purpose is to provide cut-out characters with excellent wear resistance. To provide a method for economically manufacturing formed synthetic resin molded products, that is, dark-colored synthetic resin molded products with patterns such as light-colored letters and symbols that have excellent wear resistance, through a simple process. It is to do so.

<Conventional technology> Regarding key caps among synthetic resin molded products,
The explanation will be given below.

In recent years, with the development of information devices such as push-button telephones, typewriters, word processors, and personal computers, the production volume of keycaps used in these devices as input means has increased dramatically. This type of keycap includes a light-colored keycap with a pattern of dark-colored characters and symbols, and a dark-colored keycap with a pattern of light-colored characters and symbols. The present invention relates to the latter key cap manufacturing method. That is, conventional methods for manufacturing the latter key cap include (1) a method of tacho printing on the surface of the formed key cap base material, (2) a method of pouring colored ink into the recesses on the surface of the engraved key cap base material, ( 3) The so-called different-color molding method, in which the key cap body and the patterned portions of letters, symbols, etc. are injection molded using different-colored materials; (4) The key cap base material surface is molded with letters, symbols, etc. using an ink with a resist dyeing function. A method such as a so-called resist dyeing method is known in which a pattern is formed and then dyed in a dye bath.

<Problems to be Solved by the Invention> However, each of these methods has the following additional problems. In other words, in method (1), printing ink is piled up on the surface of the keycap base material, so there are major problems with physical properties such as abrasion resistance, and it cannot withstand long-term use. It has some drawbacks, such as a poor feel when touching the keys.

Method (2) requires making a mold for each character/symbol, which increases the cost of the mold, and is completely unsuitable in the current situation as small lots and products become more diverse. It requires a process of pouring colored ink into each key cap and then wiping off unnecessary ink, which requires manpower and is extremely low in productivity.Dust tends to accumulate in the recesses of letters and symbols, making the key cap surface easily dirty. It has disadvantages such as the colored ink easily coming off, it cannot withstand long-term use, and the touch of the key is not good.

Method (3) has the advantage of excellent physical properties such as abrasion resistance and a good feel when touching the keys, but as with method (2), each character/symbol is It is necessary to create a mold, which increases the cost of the mold, and it is completely unsuitable in the current situation where small lots and a wide variety of products are being produced.It is difficult to express fine line parts such as letters and symbols. have.

Method (4) has drawbacks such as extremely low workability and productivity because the dyeing process for forming the pattern is a wet process.

<Means for Solving the Problems> In view of the current situation, the present inventors have conducted extensive research and consideration in order to eliminate all of the above-mentioned drawbacks of the conventional technology, and as a result, have developed a method for forming patterns by dyeing. By combining this method with the above-mentioned different color molding method or resist dyeing method, we have discovered that all of the above-mentioned drawbacks can be solved at once, and we have finally completed the present invention. That is, the present invention provides a pattern layer in which desired characters, symbols, etc. are formed as punched characters using an ink containing a heat-transferable dye, and at least a portion of the pattern forming surface where the punched-out characters are formed is coated with the heat-transferable dye. The pattern is formed on the pattern-forming surface of a synthetic resin molded product made of a synthetic resin that is light in color compared to the dye and the other part is dark in color, the same color as the heat transferable dye, and then heat-treated. A character characterized in that desired punched characters are formed on the patterned surface by thermally migrating the heat-transferable dye in the pattern layer, and then unnecessary materials on the patterned surface are removed.・This is a method for manufacturing synthetic resin molded products with symbols.

Hereinafter, the present invention will be explained in detail using the drawings.

In the key cap base material 1 according to the present invention, at least the portion of the pattern forming surface 2 where the punched characters 3 are formed is lighter in color than the heat-transferable dye of the pattern layer 4, which will be described later, and the other portions are It is made of a synthetic resin with the same deep color as the heat-transferable dye. The light-colored portion A is a portion that will become a pattern of cut-out characters such as characters and symbols formed on the keycap, and the dark-colored portion B is a portion that will be the main body of the keycap. The light colored part is
It may be made to form the entire surface of the pattern formation surface (see Figure 1-a), or it may be made to form a part of the pattern formation surface (at least the part where the punched character part is formed) (Fig. 1-b). (see figure). Furthermore, when patterns such as letters and symbols are applied to two sides of the keycap base material, for example, the top surface and the front surface, it goes without saying that these two sides may be composed of light-colored parts ( (See Figure 1-c).

In order to configure the key cap base material according to the present invention in this manner, it is preferable to produce it by the following method. That is, the so-called different color molding method involves injection molding a light colored part and a dark colored part using different colored materials.
Alternatively, a light-colored key cap base material is molded by injection molding using a light-colored material, then a resist dyeing layer is formed using an ink with a resist dyeing function on the part where the light-colored part will be formed, and then a dark color is formed. It is preferable to use a so-called resist dyeing method, in which the resist dyeing layer is dyed with a dye, and then the resist dyeing layer is removed. In consideration of workability, productivity, etc., the unique molding method is suitable.

In addition, in the present invention, a different color molding method may be used when producing the key cap base material, but the different color molding method in the present invention differs from the above-mentioned conventional method in that each letter/symbol is made with gold. It does not require a mold, and the same mold can be used as long as the key cap has the same shape, making it extremely suitable even in the current situation where small lots and a wide variety of products are being produced. .

The material for the key cap base material may be any material that can be dyed with a heat-transferable dye to be described later. Examples include polyethylene terephthalate, polybutylene terephthalate, polycarbonate, triacetate, diacetate, polyether sulfone, aromatic nylon, 66-nylon, polyacetal, and the like.

Next, the pattern layer in the present invention will be explained in detail. The ink binder constituting the pattern layer may be any resin as long as it does not melt and cause pattern deformation during the subsequent heat dyeing treatment. In particular, hot strong cellulose resins are good. As the heat-transferable dye that can be used in the pattern layer, select and use a dye that has the same color as the dark colored part of the key cap base material and that can be heat-transferred and dyed to the key cap base material by heat treatment. do it. For example, disperse dyes, cationic dyes (including basic dyes), acidic dyes, reactive dyes, etc. may be used, and an appropriate selection may be made from among these. When selecting the heat-transferable dye, it is desirable to consider the relationship with the key cap base material. For example, if the key cap base material is polyacetal, polycarbonate, polyether sulfone, polyethylene terephthalate, polybutylene terephthalate, or acrylic, use a disperse dye or cationic dye as the dye, and if the key cap base material is nylon, use an acid dye as the dye. The dye or disperse dye is applied to the key cap substrate such as cellulose,
In the case of rayon and acetate, it is desirable to use disperse dyes or reactive dyes as the dye. Next, the method for manufacturing the key cap will be described in detail.

First, the pattern layer is formed on the pattern formation surface of the key cap base material by screen printing, tacho printing, transfer printing, etc.
(see figure).

Next, the keycap base material on which the pattern layer is formed on the patterned surface is heated and dyed under predetermined conditions. By this heat dyeing, the parts other than the cut-out characters are dyed in the same color as the dark colored part of the key cap. The conditions for heat dyeing vary depending on the type of resin and dye that make up the keycap base material.
The temperature is 50°C to 200°C for 10 seconds to 120 minutes. Examples of heat dyeing methods include heating in an oven, heating with a hot roll, heating with a padded rubber, and heating with far infrared rays.

After the heat dyeing treatment, unnecessary materials remaining on the pattern-formed surface of the keycap base material are removed by a method such as solvent cleaning.

By doing this, it is possible to obtain a key cap 5 with the color of the dark color portion on which cut-out characters are formed with the color of the light color portion (see FIG. 3).

In the above explanation, the cut-out character portion of the pattern layer is formed by not applying a heat-transferable dye, and therefore, the cut-out character portion is formed on the background of the light-colored portion of the key cap base material. It is expressed in color. However, in the present invention, not only this, but also the cutout character portion can be colored in any color. That is, by forming the cut-out character portion of the pattern layer using an ink containing a heat-transferable dye that is darker than the light-colored portion of the keycap base material, the cut-out character portion is colored in an arbitrary color. It is also possible.

Furthermore, if there are a plurality of cut-out character portions in the pattern layer, it is easy to color each of them in a desired color.

Further, the cutout character portions of the pattern layer may be made of ink having a resisting function. In this case, the cutout character portions are never dyed by the dye of the pattern layer, and a clear pattern can be formed.

In addition, when forming the pattern layer as described above, if registration is required for the pattern layer,
Preference is given to using transfer printing methods. This is because the registration is performed on a sheet-like object and can be easily performed.

<Effects of the Invention> Since the present invention has the above configuration, it overcomes the drawbacks of the conventional octopus printing method, pouring method, different color molding method, resist dyeing method, etc., namely, abrasion resistance, key touch feel, Key caps with cut-out characters that have excellent abrasion resistance can eliminate all drawbacks such as productivity and reproducibility of fine characters. The dark-colored key caps can be manufactured economically through a simple process, and have extremely high industrial value.

Although the above explanation has been about the method for manufacturing key caps with letters and symbols, the present invention is not limited to key caps, but can be applied to various molded products that can be dyed with heat-transferable dyes. It goes without saying that it is possible.

[Brief explanation of drawings]

1-a, 1-b, and 1-c are perspective views of the key cap base material according to the present invention, and FIG. 2 shows a patterned layer on the key cap base material shown in FIG. 1-a. FIG. 3 shows a cross-sectional view of the key cap obtained by the present invention, and a perspective view of the key cap obtained according to the present invention. In the figure, 1... Key cap base material, 2... Pattern forming surface, 3... Cut out characters, 4... Pattern layer, 5... Key cap with letters/symbols, A... Light colored part, B...
dark colored part.

Claims (1)

[Scope of Claims] 1. A pattern layer in which desired characters, symbols, etc. are formed as punched characters using an ink containing a heat-transferable dye, at least a portion of the pattern-formed surface where the punched-out characters are formed undergoes the heat transfer. The pattern is formed on the pattern-forming surface of a synthetic resin molded product made of a synthetic resin that is light in color compared to the heat-transferable dye, and the other parts are dark in color, the same color as the heat-transferable dye, and then,
A heat treatment is performed to thermally transfer the heat-transferable dye in the pattern layer to form desired punched characters on the pattern-formed surface, and thereafter, unnecessary materials on the pattern-formed surface are removed. A method for manufacturing synthetic resin molded products with characters and symbols. 2. Manufacture of a synthetic resin molded article with characters and symbols as set forth in claim 1, characterized in that the cut-out character portion of the pattern layer is formed by not applying ink containing a heat-transferable dye. Method. 3. The cut-out character portion of the pattern layer is formed using an ink containing a heat-transferable dye that is darker in color than the light-colored portion of the synthetic resin molded article. A method for manufacturing synthetic resin molded products with characters and symbols. 4. The method for manufacturing a synthetic resin molded article with characters and symbols as set forth in claim 1, wherein the cutout character portions of the pattern layer are formed using ink having a resisting function. 5. A synthetic resin molded product with characters and symbols as set forth in claim 1, wherein the light-colored part and the dark-colored part of the synthetic resin molded product are produced by a different-color molding method. manufacturing method. 6. The light-colored part and the dark-colored part of the synthetic resin molded product form a resist dyeing layer using an ink with a resist dyeing function on at least the part where punched characters are to be formed on the pattern forming surface of the light colored synthetic resin molded product. A step of dyeing the synthetic resin molded article with a dye of the same color as the heat-transferable dye of the pattern layer, and a step of removing the resist dyeing layer. A method for manufacturing a synthetic resin molded product with characters and symbols as described in item 1.