JPS6077998A - Manufacture of ornament - Google Patents

Abstract

PURPOSE:To obtain an ornament having a lustrous pattern of a crystal structure on the surface by annealing a worked article of gold or a gold alloy and electropolishing it in a bath consisting of a chloride, phosphoric acid and water. CONSTITUTION:A worked article of gold or a gold alloy is annealed by a proper method, and it is electropolished by immersion in a bath consisting of about 50- 300g/l chloride such as NaCl, about 50-500ml/l phosphoric acid and the balance water. The surface of the worked article is etched, and an ornament having a lustrous pattern of a crystal structure on the surface is obtd. Since the bath does not contain harmful substances such as cyanogen and chromic acid and other heavy metallic elements, when the bath is deteriorated, it is easily recovered, and waste water is discharged without causing environmental pollution.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an ornament, and more particularly to a method of manufacturing an ornament that creates a pattern of crystal structure on the surface of an ornament made of gold or a gold alloy.

Conventionally, ornaments made of gold or gold alloys, such as gold metal plates, rings, presslets, pendants, wristwatch sides and frames,
In order to create a crystal structure pattern in processed products such as eyeglass frames, necklaces, tie fasteners, and cufflinks, it has been common to anneal the processed products and then electrolyze them in a cyan bath or chromium oxide bath. H20KCN as a cyan bath
System bath 1 (20-KCN-2 CO311AuC14
[The chromium monide bath is H20CH3C0O]
HCr2O3-based baths were used in each case.

However, both baths are extremely dangerous because they contain harmful substances such as cyanide and chromium, and when the baths become obsolete, they have the disadvantage that they must be treated with special equipment.

On the other hand, there are H2O0CI baths as electrical PJ polishing baths that do not contain these harmful substances, but they are not desirable for decorative items because they cause a loss of surface luster and erase the crystal structure planes created by annealing. .

Therefore, there is a strong desire for an electrolytic polishing bath that brings out the crystallographic planes more clearly and does not lose surface gloss.
There has been a strong desire to quickly establish a method for manufacturing ornaments having a gold or gold alloy crystal structure pattern.

The present invention has been made to meet the above requirements.

The present invention provides a decoration characterized in that a processed product made of gold or a gold alloy is annealed and then electrolytically polished in a bath of chloride, phosphoric acid, and water to have a crystal structure pattern of gold or a gold alloy. Method for manufacturing products, especially chloride 50-30'Og/
It, phosphoric acid 50-500 m7! /e, a method for producing decorative items using an electrolytic polishing bath characterized by comprising residual water.

In the manufacturing method of the present invention, a processed product made of gold or a gold alloy is used because gold or a gold alloy has a golden color. Examples of gold alloys include Au-g-Cu alloy, this alloy to which Zn, Ni, etc. are added, and Au-N.
1-Cu-Zn alloy, Au-Ag-Pd alloy, Au-Fe alloy, Au-Ni alloy, Au-Cu-
Examples include Pd-based alloys.

Further, the reason why a workpiece made of gold or a gold alloy is annealed is to create a crystalline structure plane on the surface of the decorative item.

If the textured surface of the processed product remains unchanged, no matter how much electrolytic polishing is performed, the crystalline texture pattern will not be obtained, and only a matte surface or a mirror-like glossy surface will be changed. By annealing at an appropriate temperature and time, crystals can precipitate along the grain boundaries to create a crystal structure plane of a desired size.

The atmosphere at this time may be in a vacuum or in the air, and may be oxidizing, reducing, or neutral. In the present invention, the reason why the electrolytic 1iIT polishing is performed in a bath consisting of chloride, phosphoric acid, and water is to make the crystalline structure surface stand out in the crystalline structure pattern while maintaining the surface gloss. Gold and gold alloys are not electrolytically etched in a bath consisting only of phosphoric acid and water.

The luster of the gold surface will be lost. Therefore, chloride ions, which dissolve gold, and alkaline metal ions or alkaline earth metal ions, which suppress the action of gold, are required. For this reason, chlorides are used. Preferred chlorides include NaCl, KCI, etc. .

CaCl2. Examples include MgCIz. The electrolysis method in the present invention includes alternating current voltage, direct current voltage, combination of alternating current and direct current, pulsed voltage, and the like.

In the bath of the present invention, the chloride content ranges from 50 to 300 g/
The reason why gold or gold alloy is melted is 1 when it is less than 50g/β.
This is because the amount of chlorine ions that undergo +M is too small and shortens the life of the bath.If the amount exceeds 300g/ρ, the amount of chlorine ions increases/8 and the decomposition force becomes too strong, reducing the luster of the surface of gold or gold alloy. This is because you will lose it.

In addition, the range of phosphoric acid was limited to 50-500mβ/l, which is 50m7! Below /β, the ability to stabilize the bath is weak and the surface of gold or gold alloy loses its luster.
If it is more than /1, the movement of chlorine ions becomes slow and unevenness tends to occur, which is not practical. In particular, if it exceeds 800m274, it loses its luster and cannot be used as a decorative item.

Examples and conventional examples will be described below.

[Example 1] A rolled gold plate with a width of 10I x length of 5 (1+II x thickness of 0.5+u) was annealed at 600° C. for 30 minutes in the air.

This annealed product was halved with Na CI 150g/I (,
Phosphoric acid 200ml/12. Immerse in a bath of residual water and P
, C5008/dm' 20 seconds electrolytic 1IJI polishing revealed a 7.2μ (0g035) etched crystal structure with a glossy surface of about 1 fin.

[Example 2] A u-12,5% A g -1 with the same shape as Example 1
, 2.5% Cu alloy plate was annealed in air at 800°C for 10 minutes.

Only half of this annealed product is Mg 01280g/j! , phosphorus M 500mj2/II, '6 in muddy water bath
i? R and electrolytically polished for 60 seconds with 1008/dm2 current for 2 seconds and pause for 0.5 seconds, resulting in 8.1μ (0g039)
A crystal structure of approximately 1 m++ with a highly etched and glossy surface appeared.

[Conventional example]

Half of the same annealed product as in Example 1 was treated with hydrochloric acid 200 mρ/1.
2. It was immersed in a bath of 200 ml/12 of phosphoric acid and residual water and electrolytically polished for 20 seconds with P, C5008/dm'. Although it was etched by 4.7μ (0g045), it lacked luster and no crystalline structure was observed.

As described in detail below, according to the manufacturing method of the present invention, a shiny crystal structure pattern can be obtained on the surface of an ornament, so that it can provide value as a novel ornament.
There is fruit. Furthermore, since it does not contain harmful substances such as cyanide or chromic acid, and does not contain other heavy metal elements, it is easy to recover even when the bath becomes obsolete, and there are no pollution problems with drainage.

Applicant Tanaka Kikinzoku Kogyo Co., Ltd.

Claims (1)

[Claims] ■) A workpiece made of gold or a gold alloy is annealed and then electrolytically polished in a bath consisting of chloride, phosphoric acid, and water to have a crystal structure pattern of gold or a gold alloy. A manufacturing method for distinctive ornaments. 2. The bath according to claim 1 contains 50 to 30 chlorides.
h/j! , phosphoric acid 50-500mj! / It
, a method for producing an ornament characterized in that it is made of leftover water.