JPS6246997B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing, by an etching method, a mold used for manufacturing a circuit board by a die stamp method.

The conventional method of manufacturing circuit board manufacturing molds using the die stamping method using the photoetching method has the complexity of the manufacturing process, as the photoetching process is divided into two stages, and there is also a problem in the precision process during the process. Requires extremely high level of skill, such as advanced copying techniques and copy correction techniques.
It was very difficult to manufacture high quality molds.

The present invention has been made for the purpose of eliminating such conventional drawbacks and providing a method for easily manufacturing a mold for manufacturing a circuit board.

The explanation will be given below based on the drawings.

FIG. 1 is a diagram showing the conventional manufacturing process of this type of mold. First, as shown in Fig. A, an original pattern is prepared by tracing a positive pattern 2, which is two to three times larger than the desired circuit pattern, on the original paper 1. Next, using the original drawing, a negative film 3 having a pattern 2a of the same size as the desired circuit pattern is produced as shown in FIG. Furthermore, as shown in Figure C, a photoresist 4 is applied onto a mold material 5 such as a steel material with a polished surface and dried. Next, the negative film 3 is placed in close contact with the photoresist 4, irradiated with light from above, and the photoresist 4 is exposed and developed to form a desired circuit pattern as shown in Figure 2. Only the photoresist 4a of the removed portion remains on the surface of the mold material. Next, when the mold material 5 with only the photoresist 4a left on its surface is immersed in an etching solution (for example, a ferric chloride solution), only the portion of the mold material on which the photoresist 4a is not formed is removed, as shown in Figure E. A recess 6 is formed by etching. Thereafter, when the photoresist 4a is removed, a mold 5a having a flat surface (flat mold) is produced as shown in FIG. moreover,
As shown in FIG.
Fill until it is flush with the surface. The color of the epoxy resin 6a should be symmetrical with the color of the surface of the mold material, and should be such that the difference between the resin part and the mold material part is clearly visible when photographed. Here, the completed flat mold 5
In many cases, a does not have exactly the same dimensions as the pattern 2a of the negative film 3, and an exact copy of the flat mold 5a must be made in order to form the necessary blades in the circuit board manufacturing mold. No. The planar mold 5a is copied by accurately taking a photograph of the surface of the mold material filled with the epoxy resin 6a. At this time, since the mold surface is polished and has a high light reflectance, advanced technology and skill are required to clearly photograph the boundary between the flat mold part and the epoxy resin part. A positive film is made from the negative film thus obtained by photography, a photograph is taken while slightly shaking the positive film, a negative film is made, and then a desired mold is molded using ordinary photographic methods as shown in Fig. A positive film 3a having the circuit pattern 2b modified to have a circuit width narrower than the circuit width is obtained. Creating a positive film 3a having the circuit pattern 2b modified in this manner requires a sophisticated technique of slightly shaking the film. next,
A photoresist is applied to the surface of the mold material whose recesses 6 are filled with epoxy resin 6a, dried, the positive film 3a is placed on the photoresist in a predetermined position, and exposed by irradiating light from above. When developed, the photoresist 4b is formed into a pattern that slightly protrudes onto the flat mold 5a as shown in FIG.
is formed. Next, when the mold material 5 is immersed in an etching solution, the planar mold part on which the photoresist 4b is not formed is removed, as shown in FIG. Further, when the photoresist 4b and the epoxy resin 6a are removed, a mold having a blade 5b as shown in the diagram is completed.

As can be seen from the above explanation, the conventional mold manufacturing method used for manufacturing circuit boards by die stamping has disadvantages such as the complexity of the photo-etching process, which is divided into two steps, and the need for advanced photographic technology. It was hot.

Before entering into the description of the present invention, a method for producing bag letters with background patterns using photosensitive paper (direct reversible paper) coated with a direct reversal emulsion, such as Kodagraph Transfer Paper TPP5 manufactured by Kodatsu Corporation, will be explained. First, as shown in FIG. 2, when direct reversible paper (hereinafter referred to as TPP5) 9 is exposed to strobe light 11 with an original 10 in close contact with it, light is masked by the original 10 and a portion 12 that is not exposed to light is removed. The part 13 that was exposed to diffused weak light and remained inverted, and the part 14 that was re-inverted by high-intensity strobe exposure.
It has the characteristic of being able to FIG. 3 shows an example in which bag letters with background patterns are produced using this special feature.

Figure 3 a-1 shows the character pattern 8 for “i”
It is a top view of the positive film 7 with a-2
The figure is a sectional view thereof. Figure b-1 is a plan view of a film 7a having a background pattern, for example, a mesh pattern 8a, and figure b-2 is a cross-sectional view thereof. In order to produce bag letters with a background pattern using these two films 7, 7a and TPP59, first, as shown in figure c, the film 7a with a mesh pattern is made into TPP59.
After irradiating with tungsten light, the film 7a is removed, and then, as shown in Figure d, a positive film 7 with a character pattern is brought into close contact with the TPP 59, exposed to strobe light, and then developed.
A negative film of the bag character "I" with a mesh pattern as shown in the figure is completed.

In the present invention, the direct reversible paper TPP5 having the characteristics described above is used to produce a negative having a bag letter-like pattern with a background pattern corresponding to a desired circuit pattern, which is necessary for manufacturing molds for circuit board production. By producing a film and using the negative film, it is possible to easily produce a mold for producing a circuit board.

The present invention will be explained based on FIG.

FIG. 4 shows the process of manufacturing a mold for manufacturing a circuit board according to the present invention. FIG. A shows a cross-sectional view of a negative film 3b having a cross-hatched pattern corresponding to a desired circuit pattern prepared by the same method as described in FIG. 3. First, as shown in Figure B, a photoresist 4c is applied onto the mold material 5 and dried. Next, the negative film 3b is brought into close contact with the photoresist 4c, exposed, and then developed, leaving only the resist 4d on the mold material 5, as shown in FIG. Next, when the mold material 5 is immersed in an etching solution, at the beginning of the etching stage, a resist is formed in a mesh pattern in the portion of the mold material corresponding to the desired circuit pattern, as shown in Figure D. Therefore, the etching speed is slower than that of the mold material portion 6b other than the circuit pattern, and side etching has not progressed so much that the resist formed in a mesh shape still adheres to the mold surface.
However, as etching progresses, side etching also progresses, and eventually the mesh-like resist that has adhered to the surface of the mold material separates from the surface of the mold material. When the etching progresses further and a blade 5b' of a suitable shape is formed as shown in Fig. E, the mold is removed from the etching solution. Furthermore, the resist 4d attached to the surface of the mold material is removed, and the blade 5 as shown in Fig.
A circuit board manufacturing mold having b' is obtained.

As can be seen from the above explanation, according to the method of manufacturing a mold for manufacturing a circuit board of the present invention, the etching process is also a single step, and very advanced photographic technology is not required, and this type of mold can be easily manufactured. It has the great advantage of being able to be manufactured.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the manufacturing process of a mold for manufacturing a circuit board using the conventional die stamp method, and Figure 2 is a diagram showing the manufacturing process of a mold for manufacturing a circuit board using the conventional die stamp method.
A diagram for explaining the characteristics of photosensitive paper coated with a direct reversal emulsion, FIG. 3 is a diagram showing a method for producing a negative film using the photosensitive paper, and FIG. 4 is a diagram for explaining the characteristics of a photosensitive paper coated with a direct reversal emulsion. It is a figure which shows the manufacturing process of a metal mold|die. 1: Original paper, 2: Enlarged circuit pattern, 3:
Negative film, 4: Photoresist, 5: Mold material, 6: Recess, 7: Film, 8: Character pattern, 9: Direct reversible paper (TPP5), 10: Original, 11: Strobe light, 1
2: unexposed part, 13: inverted part, 14: re-inverted part, 15: tungsten light, 2a: circuit pattern (negative), 2b: circuit pattern (positive), 3a: positive film, 3b :
Negative film, 4a, 4b, 4c: photoresist, 5a: plane mold, 5b': blade, 6a: epoxy resin, 7a: film, 8a: mesh pattern.

Claims (1)

[Claims] 1. A step in which a film with a pattern to be used as a background pattern is directly brought into close contact with photosensitive paper coated with an inversion emulsion and exposed to tungsten light, and the film with a pattern to be used as a background pattern is removed to form a positive image with the desired circuit pattern. A step of bringing the film into close contact with the photosensitive paper, exposing it to strobe light, and developing it to create a negative film having a circuit pattern in the form of a bag letter with a background pattern, and a step of applying a photoresist to the surface of the mold material. A negative film having the circuit pattern in the form of a bag letter with background pattern is closely attached to the photoresist and exposed, and then developed; A step of manufacturing a mold corresponding to the desired circuit pattern by an etching method. A method for manufacturing a mold for manufacturing a circuit board, characterized by comprising: