JPS6039223B2 - Manufacturing method of circuit pattern punching mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a mold for punching and press-molding a circuit pattern of a circuit board, and more particularly to a method for manufacturing a mold using a photo-etching method.

The conventional mold manufacturing method using the photoetching method requires, for example, a two-step photoresist process and a resin embedding process. In particular, in the resin embedding process, corrosion-resistant epoxy resin is used in the voids formed on the surface of the mold material. This process requires considerable effort and skill, making it extremely difficult to consistently obtain molds of consistently high quality. Therefore, the present invention aims to improve the shortcomings caused by the photo-etching method as described above, to shorten the time without requiring manual skill work elements, and to provide a circuit that can easily obtain molds of consistently high quality in the process. An object of the present invention is to provide a method for manufacturing a pattern punching die. Embodiments of the present invention will be described below based on the drawings. First, the surface of the mold material 1, which has been heat-treated to increase its hardness, is heated to 0.
After mechanically polishing at a rate of about 2 to 0.3 teeth/m, the surface is chemically smoothed by known means. As this chemical surface treatment, pickling with phosphoric acid or the like after steam trichloride degreasing is suitable. A photoresist film 2 is quickly applied onto the mold material 1 after surface preparation treatment before the surface is oxidized. In forming this photoresist film 2, two types of photoresists, negative and positive, are prepared, and the characteristics of these two types of photoresists are as follows:
The selection condition is that it has resistance to the developer of the other positive photoresist, for example, a rubber-based or polycinnamic acid-based negative-type photoresist and a diazo-based positive photoresist (Shipley's AZII).
1 (trade name), etc.), the negative type photoresist after photocuring will not be attacked by the alkaline developer of the positive type photoresist and will pass through the process of the present invention. Next, a circuit pattern is formed on the mold material 1, but in order to form the circuit pattern, one negative film and one positive film each are prepared in advance as original films. The negative film has a line drawing that is X/skin smaller in the line than the desired pattern, and the positive film has a line drawing that is larger than the desired pattern in the line by Ym/. In that case, the middle dimension of the required circuit pattern is Am/, the required dimension of the tip of the blade part 12 is D/en,
If the etching factor of the etching machine used is E, then X and Y are calculated by the following formula. X = Sparrow number ten
‐‐‐・‐‐‐‐‐(i}Y=number ‐‐‐
‐‐‐‐‐Naka However, the following range is the condition in the above formula.

Blue X<A -------.Next, as shown in FIG.
One method is to interpose a transparent polyester film 6 of an appropriate thickness between the master film 5 and the unexposed film 4, and then integrate these into a sandwich-like structure, which is then exposed to light to adjust the line drawing. This kind of adjustment in the line can be done by adjusting the thickness of the intervening polyester film 6. In that case, for example, by using a polyester film 6 with a thickness of 125 mm, the thinning in the line of 140 mm or the thinning in the line of 80 mm can be achieved. The thickness in the line will be obtained as a result. Furthermore, by controlling the exposure amount and development time, the amount of light can be reduced, for example, from 0 to 3.
It is possible to adjust the line between 0 and 1. After applying about 3 to 4 layers of negative type photoresist thin film onto the mold material 1 using a bonding method, spinner, spray, etc., it is pre-baked and then coated with a negative film to form a thinner line than the required circuit pattern. The circuit pattern 7 was exposed and developed with a specified developer, and then a positive type photoresist thin film was applied in the same way to about 5 to 7 layers. After pre-baking, a positive film was used to create a Y skin/skin pattern that was better than the required circuit pattern. A laminated circuit pattern 8 covering the circuit pattern 7 is formed by exposing and developing the line drawing in the thick line. The mold material 1 has surface circuit patterns 7 and 8.
The adjacent castle is etched away to the required depth B and the empty space 9 is removed.
is formed. The etching solution used at this time is usually about 5
A ferric chloride solution heated to about 37° C. Be at 0.030°C is common, but other etching solutions that do not soak the photoresist may be used. Then, the entire surface of the positive photoresist thin film of the mold material 1 is exposed again, and only the positive photoresist thin film is removed with a developer, and the developer is used to form a circuit without soaking the negative photoresist thin film. Pattern 7 is retained as is. In that case, if the negative type photoresist used is resistant to the positive type photoresist stripping solution, it can be removed immediately after etching without the need for re-exposure of the entire surface. When using Kodak's AZII1 (trade name) and Kodak's KTFR (trade name) as a negative type photoresist, since AZIII can be easily peeled off with methyl ethyl ketone, it is possible to remove the circuit with KTFR by treating it for an appropriate time. No untoward damage is caused to the pattern. Also, depending on the etching solution and etching equipment used, an overhang may occur at the side edge of the circuit pattern 8 of the mold material 1, but this overhang may be removed using the etching solution for a few seconds after removing the positive photoresist. The overhang portion (burr portion) can be removed by immersion in water, and since the chemical reaction occurs quickly, the overhang portion (burr portion) can be removed without adversely affecting the shape of other portions. In addition, in order to keep the above-mentioned overhang to a small amount, it is effective to add a side edge prevention agent to the etching solution, which forms a chelate compound with the metal wall surface of the mold material 1, and reduces the spray pressure of the etching solution. This takes advantage of the fact that the etching speed of the small wall surface is slower than that of the bottom. After the cavity 9 of an appropriate shape is formed on the mold material 1 as described above, the exposed metal portion on the surface of the mold material 1 is covered with a plating metal 10 for etching resist. The selection conditions for this plated metal 10 are that it is not immersed in the etching solution of the mold material 1, its thickness is set to withstand the etching time required for etching the void space 9, and it is etched using a ferric chloride solution. In this case, good results can be obtained by plating with 2 to 3 layers of gold or about 20 layers of lead. Next, the negative type photoresist is removed from the mold material 1 using a specified stripping solution, and the removed portion is etched away to a required depth C to form a recess 11, which is connected to the cavity 9. Although the amount of overhang at the side edge portion is small because it is shallow compared to If sharpness is desired, the blade portion 12
The overhang portion can be removed by mechanically polishing the upper end portion by several degrees to expose the upper end metal surface on the blade portion 12 while leaving the wall surface of the recess 11 covered with the plated metal 10, and performing soft etching. A blade portion 12 having an appropriate shape is obtained. Further, as another means for sharpening the upper end of this blade part 12, the plated metal 10 at the upper end part can be selectively removed chemically. In this case, a porous sheet impregnated with a plating stripping solution, The mold material 1 may be placed on felt, paper, hard sponge, etc. with the cutter 12 facing downward, and only the tip of the cutter 12 may be immersed in the stripping liquid. Thereafter, the mold material 1 is soft-etched with an etching solution to form the blade part 12 using the same principle as mechanical polishing.
The burr at the tip is removed, and the plated metal 10 covering the recess 11 is used as a mold without being removed. As explained above, the present invention provides a circuit pattern on the surface of a mold material and a laminated circuit that covers the circuit pattern by using a negative photoresist film with a smaller line than a desired circuit pattern and a positive photoresist film with a thicker line. Patterns are formed one after another, and voids are formed adjacent to the patterns by etching, which simplifies mold production and improves quality, unlike in the past, where the voids were filled with resin by hand. It can be done without deterioration.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a cross-sectional view of a mold, FIG. 2 is a cross-sectional view of a state in which a circuit pattern is formed on the surface of the mold, and FIGS. 3 and 4 are views of molding. FIG. 5 is an explanatory diagram of a cross-sectional view of the mold in progress, FIG. 5 is an explanatory diagram of the process of creating an original film, and FIG. 6 is a diagram of the manufacturing process of the mold according to the present invention. 1...Mold material, 2...Photoresist film, 4...Unexposed film, 5...
Master film, 6... Polyester film, 7... Circuit pattern, 8... Laminated circuit pattern, 9... Blank space, 10... Plating Metal, 11... recessed part, 12... blade part. Figure 1: Fin Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1 In a mold manufacturing method for punching and forming a circuit pattern from metal foil, the first step is mechanically polishing the surface of the hardened mold material and then chemically smoothing it, and forming the required circuit pattern on the surface of the mold material. a second step of forming a circuit pattern by using a negative photoresist film with a smaller twisted line width, and a third step of forming a covering circuit pattern on the circuit pattern by using a positive photoresist film with a larger line width than the required pattern. a fourth step of forming an escape groove of punched metal foil at a position adjacent to the circuit pattern forming portion on the surface of the mold material by etching;
a fifth step of removing the positive photoresist in the third step with a stripping solution or a developer after exposure; a sixth step of covering the exposed metal portions on the surface of the mold material with an etching resist plating; and the second step. a seventh step of peeling off the negative photoresist; and an etching step of forming a pressing recess in the negative photoresist removed portion of the mold material and forming a cutter on the side edge of the pressing recess. A method for manufacturing a mold for punching circuit patterns.