JPS6046362A - Preparation of decorative material - Google Patents

Abstract

PURPOSE:To form a reddish purple film execellent in corrosion resistance, by a method wherein diffusion preventing under coat plating is applied to a noble metal such as decoration grade silver and, thereafter, a plating film comprising gold and Al is formed by dry plating in an oxidative atmosphere. CONSTITUTION:Diffusion preventing under coat plating is applied to decoration grade silver, platinum, gold or an alloy thereof. In this case, Cu Ni or Mo slow in the diffusion speed of gold and Al is used in under coat plating. Subsequently, gold and Al are adhered to the under coat plating layer by dry plating in an oxidative atmosphere to form a film showing a reddish purple color.

Description

[Detailed Description of the Invention] The present invention provides rings, necklaces, bands, presslets,
The present invention relates to a method for manufacturing decorative materials using precious metals or precious metal alloys, such as on the side of the hour hand.

Conventionally, a coating of gold and aluminum that exhibits a purple color has been formed by plating on decorative silver, platinum, gold, or an alloy thereof, but this coating has the disadvantage that it only exhibits a purple color.

The present invention has been made to solve the above-mentioned drawbacks, and it is an object of the present invention to provide a method for producing decorative materials of various shapes having a reddish-purple coating of gold, aluminum, and oxygen on the surface. It is something.

The present invention involves applying a base plating to prevent diffusion on decorative silver, platinum, gold, or their alloys, and then attaching gold and aluminum by dry plating in an oxidizing atmosphere to create a reddish-purple color. It is characterized by the following.

In the manufacturing method of the present invention, decorative silver is produced by dry plating gold and aluminum in an oxidizing atmosphere.

The reason for adhering to platinum, gold, or their alloys is that they can be processed into various shapes as ornaments, and the simple purple alloy coating consisting of gold and aluminum is oxidized during manufacturing, changing the simple purple color to a reddish-purple color. This is to improve corrosion resistance and make it harder than the alloy coating itself made of gold and aluminum. Furthermore, the reason for applying a diffusion-preventing base plating on decorative silver, platinum, gold, or their alloys is that heat treatment such as brazing is performed when assembling the final decorative item. , a film consisting of gold, aluminum, and oxygen that exhibits a reddish-purple color will diffuse into platinum, gold, or their alloys, making it impossible to achieve the desired film thickness or color contrast. Decorative silver, platinum,
This is to prevent the coating from diffusing into gold or alloys thereof.

Next, specific examples of manufacturing decorative materials using the manufacturing method of the present invention will be described.

[Example 1] 10 cranes x 10n+ x 1 dragon's platinum-palladium 10
fff amount%Ni was added on the plate using a sputtering device.
Only μ II was coated, and then a gold-aluminum 22% alloy target was used to coat the target at 10 Torr.
Sputtering in Ar+02 atmosphere of 0.2n
When a thick coating was applied, the surface of the platinum-palladium 10M mass % plate exhibited a bright reddish-purple color due to the oxidation of the gold-aluminum 22fi1% alloy, and the Pinkers hardness of the surface increased from 75 to 250. Hardened. Furthermore, this platinum-palladium 10% by weight plate was heated at 600°C for 10 minutes.
Even after heat treatment in vacuum, the bright purple color did not change.

[Example 2] A sputtering device was used to coat MoO to a thickness of 5 μm on a ring with an outer diameter of 18 Tsuru and a wall thickness of 3 Dragon. When a coating of 0.2111 of gold-nyaluminum-75:25 by weight was deposited by sputtering in an Ar+02 atmosphere of Torr, the surface of the ring exhibited a bright reddish-purple color, and the surface had a Pinkers hardness.
It rose from 115 to 360 and was cured. Furthermore, even when this ring was heat treated in a vacuum for 10 minutes with soo'c, the bright reddish-purple color did not change.

In the example, the weight ratio of gold and aluminum was 78:22.
and 15':25, but the present invention is not limited to this, and in order to obtain a bright reddish-purple color, the weight ratio of gold and aluminum is 85:15 to 65:35.
A range of is preferred.

As is clear from the above explanation, the manufacturing method of the present invention involves applying a diffusion-preventing base plating to the surface of silver, platinum, gold, or their alloys, and then drying the gold and aluminum in an oxidizing atmosphere on the entire or partial surface. By attaching it by plating, it is possible to manufacture decorative materials in various shapes of reddish-purple or a mixture of reddish-purple and 402 colors, and the color tone does not change even when heated by brazing etc., so it can replace conventional manufacturing methods. It can be said that it is a groundbreaking thing that can be done.

Applicant: Tanaka Kikinzoku Kogyo Co., Ltd.

Claims (1)

[Claims] 1) Decorative silver 1 Platinum, gold or an alloy thereof is plated with a base plating for preventing diffusion, and then gold and aluminum are attached by dry plating in an oxidizing atmosphere so as to exhibit a reddish-purple color. A method for producing a decorative material, the method comprising: 2) As the base plating for preventing diffusion, Cu is used because the rate of diffusion of gold and aluminum in the base plating is slow. A method for producing a decorative material according to claim 1, characterized in that N i + M c or the like.