JP3042149B2 - Precious metal foil processing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing a noble metal foil suitably used for decoration of lacquer ware products.

[0002]

2. Description of the Related Art Lacquer ware has been developed as one of the crafts developed in lacquer producing countries such as Japan, China, Korea and Thailand. Above all, Japanese lacquer ware has excellent techniques and a variety of lacquer ware designs.
Since the surfaces of these lacquer wares are decorated with precious metal foils such as gold, silver and platinum, they are known around the world as arts and crafts with splendid beauty, and are representative of these lacquer wares For example, inkstone boxes, trays, altars, and tools are well known. The noble metal foil is generally used in a thickness of about 100 μm, and the noble metal foil is manufactured by rolling a noble metal lump such as gold, silver, and platinum to a predetermined thickness. The manufactured noble metal foil is punched out by a molding machine, processed into a noble metal piece having a predetermined shape, and attached to a predetermined position on the surface of a lacquered product to be decorated.

[0003]

In the lacquerware described above, there is a strong demand for cost reduction from the market, and the amount of extremely expensive precious metal foil used is reduced as much as possible in order to reduce the cost. It is desired that the thickness of these precious metal foils be 100 μm as an example.
m is required to be 50 μm.

However, in the case of the noble metal foil thinned to 50 μm, sagging or burrs are generated on the edge of the noble metal piece punched by a molding machine, and the noble metal piece cannot be punched cleanly. However, there is a drawback in that it is bent or deformed when performing. Also, when decorating the surface of the lacquer ware with such a noble metal piece, the noble metal piece floats from the surface due to sagging or burr on the edge of the noble metal piece, or
Problems such as peeling are caused, and there is a disadvantage that the appearance is poor and the value as an art and craft is reduced. Therefore, in order to prevent these inconveniences, it was necessary to employ a method by etching instead of a method of punching out with a molding machine.

However, when a conventional noble metal foil is subjected to an etching process, for example, as shown in FIG. 3, the obtained petal-shaped noble metal pieces 1 have the tips 2, 2, 3 and the notched recess 4 as shown in FIG. Has the disadvantage that it is rounded and loses sharpness, and it is not possible to obtain a fine pattern or a highly accurate shape, and the size of the obtained precious metal piece 1 varies greatly. There was a drawback that decorating the surface of lacquer ware made the appearance worse. These drawbacks arise from the fact that the noble metal foil is etched in units of crystal grains, and the greater the variation in the crystal grain size, the greater the variation in the pattern and shape at individual locations of the noble metal foil, Fine patterns and shapes cannot be etched. In the past, these precious metal pieces were hand-carried to the predetermined positions on the surface of the lacquer ware by hand, and these pieces were easily bent or deformed during work, resulting in reduced handling. Will be
This contributed to a decrease in work efficiency.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method of processing a noble metal foil which can effectively solve the above-mentioned drawbacks and problems.

[0007]

In order to solve the above problems, the present invention employs the following method for processing a noble metal foil.
That is, the method for processing a noble metal foil according to claim 1 forms a mask of a predetermined pattern made of a resist on the surface of the noble metal foil, and etches the noble metal foil from the mask side to form a noble metal of a predetermined shape. A piece, a support piece projecting outward from the center of gravity of the noble metal piece toward the periphery of the noble metal piece, and a connecting piece that supports the support piece in the plane direction of the support piece, which are integrally formed. And

According to a second aspect of the present invention, there is provided a method of processing a noble metal foil according to the first aspect, wherein the noble metal foil has a maximum crystal grain size of 3 μm or less. And

The method for processing a noble metal foil according to the third aspect of the present invention is the method for processing a noble metal foil according to the second aspect, wherein the raw material of the noble metal foil is melted and cast, then rolled and annealed, and then heated to 60 ° C. or less. Cold rolling is performed at a temperature, and the maximum crystal grain size of the noble metal foil is set to 3 μm or less.

[0010]

In the method for processing a noble metal foil according to the first aspect of the present invention, by etching the noble metal foil, a noble metal piece having a predetermined shape and a peripheral portion of the noble metal piece from the center of gravity of the noble metal piece. A support piece projecting toward the support piece and a connecting piece for supporting the support piece in the surface direction of the support piece are integrally formed.

In the method of processing a noble metal foil according to the present invention, the maximum crystal grain size of the noble metal foil is set to 3 μm or less, so that the variation of the crystal grain size is reduced, and the noble metal foil at the time of etching is reduced. The variation in the etching rate at each individual location is reduced, and the unevenness of the amount of etching of the noble metal foil depending on the location is eliminated. Thus, when etching is performed using a mask pattern on which a fine pattern is formed, these patterns can be accurately transferred onto the noble metal foil, and a fine pattern or shape can be etched with high precision. .

Further, in the method for processing a noble metal foil according to the third aspect, the maximum crystal grain size of the noble metal foil is 3 μm by performing cold rolling at a temperature of 60 ° C. or less after annealing.
The following is assumed.

[0013]

Embodiments of the present invention will be described below. First, a noble metal foil according to an embodiment of the present invention will be described with reference to FIG. This noble metal foil 11 has a plurality of noble metal pieces 12, 12,... Of a predetermined shape (petal type in this embodiment) arranged at equal intervals on a straight line, and each of the plurality of noble metal pieces 12,. Each of the support pieces 13 protruding outward from the center of gravity G toward the periphery 12a, and a long connecting piece 14 for supporting the plurality of support pieces 13,... In the plane direction of the support pieces 13,. It is roughly constituted from.

The noble metal foil 11 is obtained by etching a noble metal foil having a thickness of 50 μm, such as gold, silver, or platinum, and has a maximum crystal grain size of 3 μm or less.

Next, a method of processing the noble metal foil 11 will be described. First, a lump of gold, silver, platinum or the like as a raw material of the noble metal foil 11 is melted and cast to prepare a noble metal plate having a thickness of 10 mm. Next, rolling is repeatedly performed at a rolling reduction of about 10 to 20% per process to obtain a noble metal plate having a thickness of 0.1 to 0.5 mm. Thereafter, annealing is performed at 300 to 600 ° C. for 3 to 10 minutes, and then cold rolling is performed a plurality of times at a temperature of 60 ° C. or less. In this cold rolling, the rolling reduction is initially 10%, the rolling reduction is gradually increased, and finally the rolling reduction is 40 to 60%.
And Thus, the maximum crystal grain size of the noble metal foil 11 can be set to 3 μm or less.

Next, a photoresist is applied to the surface of the noble metal foil 11, a mask having a predetermined pattern formed thereon is mounted on the photoresist, and the photoresist is irradiated with ultraviolet light or the like from above the mask. To expose
A mask having a predetermined pattern is formed on the photoresist.

Next, the noble metal foil 11 is etched from above the photoresist using an etching solution such as hydroiodic acid (HI). In this etching process,
The noble metal foil 11 is etched and removed for each crystal grain size by the etchant, and the noble metal pieces 12 and 1 having a predetermined shape are removed.
The noble metal foil 11 including the support pieces 13 and the connection pieces 14 is formed.

The noble metal piece 12 thus processed
As shown in FIG. 2, the tips 21, 21, 22, and the cut-out recess 23 have clear and sharp outlines, so that a fine pattern and a highly accurate shape can be obtained.

As described above, according to the method for processing the noble metal foil 11 of the above embodiment, the plurality of noble metal pieces 12, 12,... .., Each support piece 13 protruding outward from the center of gravity G toward the periphery 12a, and a long piece for supporting the plurality of support pieces 13,... In the plane direction of the support pieces 13,. Noble metal foil 11 that is integrally processed with the connecting piece 14 of the lacquer ware.
In the case of attaching 2, the noble metal piece 12 is prevented from swinging due to the weight balance, and the noble metal piece 12 can be positioned extremely easily and reliably.

Further, the noble metal foil 11 can be processed with high precision, and the edges of the noble metal pieces may be sagged or burred, or may be bent or deformed when ejected from the mold, as is conventionally seen. Can be eliminated, and the appearance of the obtained noble metal piece is improved without variation.

During the attaching operation, these noble metal pieces 12
Is less likely to be bent or deformed, handling is improved, and work efficiency and productivity are greatly improved.

Further, the noble metal foil 11 is
Since the maximum crystal grain size of No. 1 is 3 μm or less, the variation in the crystal grain size of the noble metal foil 11 can be reduced, and the variation in the etching rate at each location of the noble metal foil 11 during etching is reduced. be able to. Therefore, non-uniformity due to the location of the etching amount of the noble metal foil 11 can be eliminated, the mask pattern can be accurately transferred onto the noble metal foil 11, and a fine pattern or shape can be etched with high precision. It becomes possible.

The raw material of the noble metal foil 11 is melted and cast,
Since repeated rolling and annealing are sequentially performed, and then cold rolling is performed a plurality of times at a temperature of 60 ° C. or less, the maximum crystal grain size of the noble metal foil 11 can be reduced to 3 μm or less.

As described above, it is possible to provide a method for processing a noble metal foil which can effectively solve the conventional disadvantages and problems.

[0025]

As described above, according to the first aspect of the present invention,
According to the processing method of the noble metal foil described, on the surface of the noble metal foil, a mask of a predetermined pattern made of a resist is formed, and by etching the noble metal foil from the mask side, a noble metal piece of a predetermined shape, Since the supporting piece projecting outward from the center of gravity of the noble metal piece toward the periphery of the noble metal piece and the connecting piece supporting the supporting piece in the surface direction of the supporting piece are integrally formed, Problems such as dripping or burrs on the edges of the noble metal pieces that were seen, bending or deformation when ejected from the mold can be eliminated, and the variation in the shape of the obtained noble metal pieces is also small. The appearance can be improved.

During the sticking operation, these noble metal pieces 12
Is less likely to be bent or deformed, handling is improved, and work efficiency and productivity are greatly improved.

According to the method for processing a noble metal foil according to the second aspect, in the method for processing a noble metal foil according to the first aspect, the noble metal foil has a maximum crystal grain size of 3 μm.
m or less, the variation in the crystal grain size of the noble metal foil can be reduced, and the variation in the etching rate at each location of the noble metal foil during etching can be reduced. Therefore, non-uniformity due to the location of the etching amount of the noble metal foil can be eliminated, the mask pattern can be accurately transferred onto the noble metal foil, and a fine pattern or shape can be etched with high precision. Will be possible.

According to the method for processing a noble metal foil according to the third aspect, the raw material of the noble metal foil is melted and cast, then rolled and annealed, and then cold rolled at a temperature of 60 ° C. or less. The maximum crystal grain size of the noble metal foil is 3
μm or less.

As described above, it is possible to provide a method for processing a noble metal foil which can effectively solve the conventional disadvantages and problems.

[Brief description of the drawings]

FIG. 1 is a partial plan view showing a noble metal foil of the present invention.

FIG. 2 is a plan view showing a noble metal piece of the noble metal foil of the present invention.

FIG. 3 is a plan view showing a noble metal piece of a conventional noble metal foil.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Noble metal foil 12 Noble metal piece 12a Peripheral edge 13 Supporting piece 14 Connecting piece 21, 22 Tip 23 Depression

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C23F 1/00-1/46

Claims (3)

(57) [Claims] A mask having a predetermined pattern made of a resist is formed on the surface of a noble metal foil, and the noble metal foil is etched from the mask side so that a noble metal piece having a predetermined shape and a center of gravity of the noble metal piece are formed. A method of processing a noble metal foil, comprising integrally forming a supporting piece projecting outward from a peripheral portion of the noble metal piece and a connecting piece supporting the supporting piece in a surface direction of the supporting piece. 2. The method for processing a precious metal foil according to claim 1, wherein the precious metal foil has a maximum crystal grain size of 3 μm or less. 3. A method of melting and casting a raw material of a noble metal foil, followed by rolling and annealing, and then performing cold rolling at a temperature of 60 ° C. or less to reduce the maximum crystal grain size of the noble metal foil to 3 μm or less. The method for processing a noble metal foil according to claim 2, wherein