JPH05217755A - Manufacture of pattern plating molded product - Google Patents

Abstract

PURPOSE:To eliminate burrs and warp by forming metallic bodies on a conductive substrate by electroplating, and then etching off the substrate to take out the discrete metallic products. CONSTITUTION:The surface of a conductive substrate 10 such as a galvanized steel sheet is coated with a resist layer. With a mask material placed thereon it is exposed to ultraviolet rays to photo-set the portion exposed to light. Thereafter the unexposed portion is dissolved by a solvent and removed from the substrate 10 surface, and an exposed portion 14 of a pattern corresponding to the shape of a target metallic copper ring is formed. Then, with the substrate 10 as a cathode copper electroplating is applied to deposit metallic copper on the exposed portion 14 of the substrate 10, thereby to form copper rings 16 and 18 on the substrate 10 surface. First, copper pyrophosphate bath is used to apply ground plating to prevent the plated coating from peeling off during the plating, and after obtaining the rings with no warp or the like, the rings are further plated with copper at high speed by a copper sulfate bath. Then, the resist layer 12 on the substrate 10 surface is dissolved by a solvent, and the substrate 10 is etched off by caustic soda or the like to take out the copper rings.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a pattern-plated molded article suitable for production of a short ring for a flat plate type rotary transformer used in a VTR or the like.

[0002]

2. Description of the Related Art A scanner portion for recording and reproducing a video signal in a VTR generally has a structure as shown in FIG.

In this figure, 100 is a fixed lower drum, and 102 is a movable upper drum. Upper drum 10
2, a video head 104 is provided at a predetermined position, and the video head 104 rotates together with the upper drum 102 together with a shaft 108 that is rotationally driven by a motor 106.

A rotary transformer 110 is provided between the upper drum 102 and the lower drum 100 to electromagnetically convert a signal and relay the signal between the video head 104 and the processing circuit.

This rotary transformer 110 is composed of a primary side transformer 112 and a secondary side transformer 114, the primary side transformer 112 is on the upper drum 102 side, and the secondary side transformer 114 is on the lower drum 100 side. Each is fixed.

As shown in FIGS. 3B and 3C, the primary side transformer 112 and the secondary side transformer 114 have grooves 118 formed on the surface of a disk body 116 made of a ferrite material.
Coil 1 for exchanging video or audio signals held in
20 and a short ring 126 made of copper between the coils 120.

This short ring 126 is used for the coil 12.
It is intended to prevent signal interference between 0 and 120, and is usually a thin wall thickness of about 0.15 to 0.20 mm.

The short ring 126 is conventionally manufactured by punching a thin copper plate into a ring shape using a die.

[0009]

However, when punching is performed using such a mold, burrs are generated on the obtained short ring 126, and the burrs cause the short ring 126 to be a disc made of ferrite. There was a problem that it could not be inserted properly into the groove 124 of the body 116.

Further, the short ring 126 thus obtained has a warp, and the warp causes a problem that the short ring 126 cannot be completely accommodated in the groove 124 of the disc body 116.

Those that cannot be accommodated in the groove 124 cannot be used as a product. Therefore, a lot of material loss occurs in the punching manufacturing of the short ring 126, and a factor that lowers the material yield rate. Was becoming.

Further, in the case of this method, the short ring 12
6 There is also a problem that an expensive mold is required for manufacturing, and a mold corresponding to each change in size and shape of the short ring 126 is required.

[0013]

The manufacturing method of the present invention has been made in view of such circumstances, and the gist thereof is a method of manufacturing a pattern-plated molded article, which comprises (a)
A step of forming a resist layer on a conductive substrate and removing the shape part of the resist layer corresponding to the molded product, and exposing the substrate surface in a pattern corresponding to the shape of the molded product; (B) a step of forming a metal layer on the exposed portion of the substrate by applying electroplating using the substrate as a cathode; and (c) removing the resist layer and etching the substrate after the plating treatment. And removing the metal molded product formed on the substrate by removing.

[0014]

As described above, according to the present invention, a metal molded product is laminated and formed on a conductive substrate by an electroplating method, the substrate is removed by etching, and a single metal molded product is taken out.

Unlike the case where the pattern-plated molded product obtained by the present invention is manufactured by punching, burrs do not occur. Therefore, when the precision conductor, for example, the short ring is manufactured by the present invention, Can be smoothly inserted into the groove of the rotary transformer.

Further, according to the present invention, since the short ring is not warped, it can be accommodated in the groove of the rotary transformer without any trouble, and the material loss is reduced, and the yield rate is increased. Can be improved.

In addition, according to the present invention, an expensive die is not required, and one plating facility can be applied to other types of products.

[0018]

EXAMPLES In order to further clarify the characteristics of the present invention, examples thereof will be described in detail below.

In this example, as shown in FIG. 1, first, a resist layer 12 having a predetermined thickness is formed by resist coating on the surface of a conductive substrate 10 such as a steel plate plated with aluminum, zinc, tin, or the like (step). I, II). Here, it is necessary to use a resist material that is resistant to the plating solution.

Next, a mask material is placed on the resist layer 12 and UV exposed to light-cur the exposed portion. After that, the non-exposed portion is dissolved with a predetermined solvent and removed from the surface of the substrate 10. This exposes the surface of the substrate 10 in a predetermined pattern.

That is, an exposed portion 14 having a pattern corresponding to the shape of the intended metal copper ring (short ring) is formed on the surface of the substrate 10 (step III). This exposed part 1
The width of 4 is, for example, about 50 to 400 μm.

Next, using this substrate 10 as a cathode, electrolytic copper plating is performed to deposit metallic copper on the exposed portion 14 of the substrate 10, and copper rings 16 and 18 are laminated on the surface of the substrate 10 (step IV). The wall thickness is, for example, 50 to 400 μm.

Here, electrolytic copper plating is performed by the following procedure. That is, first, copper pyrophosphate bath (pH 8.6 to 10.0)
Is used to perform copper plating to a film thickness of 1 to 10 μm, and thereafter, copper plating is performed to a final thickness using a copper sulfate bath.

The reason why the undercoating is first performed using the copper pyrophosphate bath in this way is to enhance the initial adhesion to the metal substrate, which prevents peeling of the plating film during plating, warpage, etc. It is possible to obtain a molded body having high flatness accuracy.

Further, the subsequent plating using a copper sulfate bath enables high-speed deposition and therefore can be processed in a short time and can prevent pattern deformation due to deterioration of the resist in the bath. This is because the efficiency can be increased.

In this example, a plurality of copper rings 16 and 18 are simultaneously laminated on the surface of the substrate 10.
Of these, only the copper ring 16 is required as a product (short ring). That is, the copper ring 18 is unnecessary as a product.

The reason why these copper rings 16 and 18 are formed at the same time is that a current is applied to the substrate 10 when electrolytic copper plating is performed.
This is to prevent the copper ring 16 from being concentrated on a specific portion of the surface and deteriorating the surface properties of the obtained copper ring 16.

After the above electrolytic copper plating treatment is completed, the resist layer 12 on the surface of the substrate 10 is then dissolved in a solvent and removed (step V). For example, a methylene chloride solution can be used as the solvent.

Next, the substrate 10 is removed by etching using an etching solution such as caustic soda (step VI), and the copper ring (short ring) 16 is taken out as a single item.

[Experimental Example] Next, an experimental example of manufacturing a copper ring (short ring) performed based on the above steps will be described.

An aluminum plate having a thickness of 0.2 mm is used as the substrate 10, and a solvent developing type liquid plating resist, specifically, OP-2 resist H manufactured by Tokyo Applied Chemistry Co., Ltd.
A resist layer 12 having a film thickness of 4 to 6 μm was formed using S-600.

After that, a mask material is covered on it and pattern exposure is performed. Then, the non-exposed portion is dissolved and removed by a solvent,
The substrate surface was exposed with a pattern having a diameter of 26 mm and a width of 150 μm.

Then, this was subjected to electrolytic copper plating. Electrolytic copper plating was performed as follows. That is, first, using a copper pyrophosphate bath as a plating solution, the temperature was 55 ° C., the pH was 8.7,
Primary plating is performed under conditions of a current density of 5 A / dm ² and a time of 5 minutes, and then a copper sulfate bath (temperature: 25 ° C.) is used to obtain a current density of 1
Secondary plating was performed under the conditions of 0 A / dm ² and 50 minutes.

After this plating treatment, the resist layer 12 remaining on the substrate surface was removed using methylene chloride, and then the substrate 1 was coated with 10 wt% caustic soda solution (60 ° C. ≦).
0 is removed by etching, and the cross-sectional shape shown in FIG.
That is, the copper ring 16 having a cross-sectional height of 0.10 mm and a width of 0.31 mm was collected.

Note that (B) and (C) show examples of other copper rings 16, and the copper ring 16 having such a shape can also be easily manufactured by this method.

The embodiment of the present invention has been described in detail above, but this is merely an example, and the present invention can be carried out in a mode in which various modifications are made based on the knowledge of those skilled in the art without departing from the spirit of the invention. is there.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing each step of an embodiment method of the present invention.

FIG. 2 is a view showing a cross-sectional shape of a copper ring obtained by the present invention.

FIG. 3 is an explanatory diagram for explaining the background of the present invention.

[Explanation of symbols]

 10 substrate 12 resist layer 14 exposed portion 16 copper ring

Claims (1)

[Claims] 1. A method for producing a pattern-plated molded product, comprising: (a) forming a resist layer on a conductive substrate and removing the surface of the substrate except the shape part of the resist layer corresponding to the molded product. A step of exposing the molded product in a pattern corresponding to the shape of the molded article; and (b) a step of forming a metal layer on the exposed portion of the substrate by electroplating the substrate as a cathode, C) a step of removing the resist layer after the plating treatment and removing the substrate by etching to take out a metal molded product formed on the substrate. ..