JPH05239682A - Electroforming method - Google Patents

Abstract

PURPOSE:To uniformize the thickness of the molding obtd. by an electroforming method. CONSTITUTION:Dummy insulating films 13 to segment the surface on a base material 11 to be applied with the more uniformized current density on the base material 11 to be formed with a plating film 14 are formed at the time of forming masking films 12 to provide desired figures on the base material 11. After the plating film 14 of the first time is formed, the masking films 12 and the dummy insulating films 13 are removed and second masking films 15 are formed in the regions where the masking films 12 are previously formed. A second plating film 17 is thereafter formed by second time of electropalting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroforming method and, more particularly, to an improvement for achieving uniform thickness of a molded article obtained by electroforming.

[0002]

2. Description of the Related Art In the electroforming method, a figure is formed on a conductor with an insulator, electroplating is performed, and the film is peeled off to obtain a product. By such an electroforming method,
For example, metal mesh printing plates used for screen printing are manufactured. FIG. 3 shows typical steps included in the electroforming method.

First, as shown in FIGS. 3A and 3B, an electrically insulating masking film 2 patterned by, for example, photolithography is formed on a conductive substrate 1. Then, in FIG. 3 (2a) and (2
As shown in b), the plating film 3 is formed on the base material 1 by electroplating except the region where the masking film 2 is formed. Next, as shown in FIGS. 3 (3a) and 3 (b), the masking film 2 is removed. Then, as shown in FIG.
As shown in a) and (4b), the plating film 3 is peeled from the base material 1. In this way, the plated film 3 provides the desired molded article.

[0004]

FIG. 4 is a sectional view showing an example of a product 4 obtained by the electroforming method, and is for explaining the problem to be solved by the present invention.

The plating deposition rate by electroplating is determined by the current density, and the higher the current density, the higher the deposition rate. In the electroforming method, since the figure is formed by the electrically insulating masking film, the area of the conductive surface is small in the peripheral portion of the portion covered with the masking film, the current is concentrated, and the current density is increased. Become. Therefore, as shown in FIG. 4, the thickness of the plating film is increased in the peripheral portion of the portion covered with the masking film, and the product 4
Cannot have a uniform thickness.

Therefore, it is an object of the present invention to provide an electroforming method capable of obtaining a molded product having a uniform thickness.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a patterned electrically insulating masking film is formed on a conductive base material, and except for a region where the masking film is formed,
A plating film is formed on the base material by electroplating, and then
The present invention is directed to an electroforming method that includes each step of removing a masking film and peeling a plating film from the base material, and has the following configuration in order to solve the above-mentioned technical problem. Is characterized by.

The step of forming the masking film includes the step of forming a dummy insulating film for partitioning the surface of the base material so as to provide a more uniform current density on the base material on which the plating film is to be formed. In addition, the step of forming the plating film,
It is performed with the masking film and the dummy insulating film formed on the base material. Further, between the step of forming the plating film and the step of removing the masking film,
The dummy insulating film is removed, and then a second plated film is formed again by electroplating.

[0009]

In the present invention, the dummy insulating film partitions the surface on the substrate to be electroplated to increase the current density,
The current density in the peripheral portion of the portion covered with the masking film is made substantially equal, and the current density on the surface to be plated is made more uniform.

[0010]

Therefore, according to the present invention, the thickness of the plated film can be made uniform, and the thickness of the obtained molded product can be made uniform.

Further, according to the present invention, after the dummy insulating film is removed, the second plating film is formed again by electroplating. Therefore, if a new masking film is formed at this time, there is a step. A molded product having a complicated shape can be easily obtained.

As described above, since the solvent is used when removing the dummy insulating film, it is efficient to remove the masking film together with the dummy insulating film. Therefore, when forming the second plating film, the second plating film is formed again on at least the region where the masking film was formed.
A masking film is formed.

In the step of forming the second masking film, the second dummy insulating film may be formed on the plating film. This second dummy insulating film, like the first dummy insulating film that has already been removed, contributes to making the current density uniform in the electroplating process.

[0014]

1 is a sectional view showing a typical process included in an electroforming method according to an embodiment of the present invention.

As shown in FIG. 1 (1), a conductive base material 1
A patterned electrically insulating masking film 12 is formed on the first layer 1. At the same time, a dummy for partitioning the surface of the base material 11 so as to give a more uniform current density on the base material 11 on which a plating film is to be formed by electroplating performed in the step of FIG. The insulating film 13 is formed.
The masking film 12 and the dummy insulating film 13 are patterned by, for example, photolithography.

Next, as shown in FIG. 1B, a plating film 14 is formed on the base material 11 by electroplating except for the region where the masking film 12 and the dummy insulating film 13 are formed. At this time, the dummy insulating film 13 acts to increase the current density in the peripheral portion of the portion covered with the dummy insulating film 13 to an extent comparable to the current density in the peripheral portion of the portion covered with the masking film 12, The current density on the base material 11 is made uniform. Therefore, the obtained plated film 14 has a substantially uniform thickness.

Next, as shown in FIG. 1C, the dummy insulating film 13 is removed. In this process,
The masking film 12 is removed together with the dummy insulating film 13. Therefore, the second masking film 15 is formed again in the region where the masking film 12 was formed. Further, the second dummy insulating film 16 is formed on the plating film 14 so as to perform the same function as the dummy insulating film 13 described above. The patterning of these second masking film 15 and dummy insulating film 16 is performed by, for example, photolithography.

Next, as shown in FIG. 1D, the second plating film 17 is formed again by electroplating except for the region where the second masking film 15 and the dummy insulating film 16 are formed.
Is formed.

Next, as shown in FIG. 1 (5), the second masking film 15 and the dummy insulating film 16 are removed,
The plating films 14 and 17 are separated from the base material 11. In this way, the desired molding is obtained by the electroforming method.

By slightly modifying the above-mentioned embodiment, it is possible to manufacture a molded product having a stepped shape and a complicated shape. FIG. 2 shows a cross-sectional view and a plan view of the metal mesh printing plate 18 obtained by this modification.

In the process of FIG. 1 (3) described above, the second
By changing the pattern of the masking film 15 of
The metal mesh printing plate 18 shown in FIG. 2 is obtained. That is, this masking film may be formed so that three second masking films 15 shown in FIG. 1C extend in series on the plating film 14. After that, the steps shown in FIGS. 1 (4) and 1 (5) are sequentially performed to obtain the metal mesh printing plate 18 shown in FIG.

The metal mesh printing plate 18 is composed of two layers, that is, a mesh portion 19 through which paste or ink is passed and a printed figure portion 20. The amount of paste or ink applied depends on the plate thickness, and therefore the thickness of the entire metal mesh printing plate must be uniform in order to perform uniform printing.
In the metal mesh printing plate obtained by the conventional method,
Since the plate thickness could not be made uniform, the printing thickness varied. When the metal mesh printing plate is produced according to the present invention, not only the mesh portion and the printed figure portion can be integrally formed, but also the plate thickness can be made completely uniform, so that the metal having a high printing thickness accuracy can be obtained. A mesh printing plate can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a typical process included in an electroforming method according to an embodiment of the present invention.

FIG. 2 is a sectional view and a plan view showing a metal mesh printing plate 18 obtained according to another embodiment of the present invention.

3A and 3B are a cross-sectional view and a plan view showing a typical process included in a conventional electroforming method.

FIG. 4 is a cross-sectional view of a product 4 obtained by an electroforming method for explaining the problem to be solved by the present invention.

[Explanation of symbols]

 11 base material 12 masking film 13 dummy insulating film 14 plating film 15 second masking film 16 second dummy insulating film 17 second plating film

Claims (3)

[Claims] 1. A patterned electrically insulating masking film is formed on a conductive base material, and a plating film is formed on the base material by electroplating except for a region where the masking film is formed. In the electroforming method, the masking film is then removed, and the plating film is peeled from the base material. In the electroforming method, the step of forming the masking film includes the base material on which the plating film is to be formed. The step of forming a dummy insulating film for partitioning the surface of the base material so as to give a more uniform current density, and Performed in a state of being formed on a material, between the step of forming the plating film and the step of removing the masking film, a step of removing the dummy insulating film,
And an electroforming method further comprising the step of forming a second plating film by electroplating again. 2. The step of removing the dummy insulating film, the step of removing the masking film together with the dummy insulating film, and then forming a second masking film again in the region where the masking film was formed. Including the process
The electroforming method according to claim 1. 3. The electroforming method according to claim 2, wherein the step of forming the second masking film includes the step of forming a second dummy insulating film on the plating film.