PROCESSING TECHNIQUE FOR HARD PURE GOLD ACCESSORIES

Abstract

A processing technique of electroforming for hard pure gold accessories, including carving waxwork, making silica molding, grafting wax, trimming wax, oiling, electroforming, wax removing and quality inspection, characterized in that LJJAS compounding agent was added to the electrolytic solution, the electroforming temperature is between 50 to 60 degrees, the electroforming speed is 0.05 g/h and pH value of electrolytic solution is between 7.0 to 7.5. Thus, even distribution, strong covering capacity, thin coating, short molding time, big size, lighy weight and high hardness can be achieved. This processing technique is particularly suitable to the gold processing industry.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119 to China Patent Application No. 200810158017.4, filed on Oct. 22, 2008, in the China Intellectual Property Office, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Technology Field

This invention regards a gold processing technique, more particularly, it regards a processing technique for hard pure gold accessories.

2. Technology Background

The range and types of gold jewelries, accessories and decorative articles are getting more and more wide and plentiful with the developing of modern industry and high technology. The demands of gold accessories in quality, appearance and size are also growing. Gold electroplating is a key stage in the processing technique of gold accessories. In current gold electroplating, some factors like gold content, pH value and working temperature of electrolytic solution will lead to maldistribution, long molding time and big thickness of gold plating, frequently arisen of shinning matte and small size, big weight and low hardness of products.

DETAILED DESCRIPTION OF THE INVENTION

The main purpose of this invention is to provide a processing technique of pure gold accessories, which can achieve even distribution, strong covering capacity, thin coating, short molding time, big size, lighy weight and high hardness.

The purpose is achieved by a processing technique for hard pure gold accessories, including carving waxwork, making silica molding, grafting wax, trimming wax, oiling, electroforming, wax removing and quality inspection, characterized in that LJJAS compounding agent was added to the electrolytic solution, the electroforming temperature is between 50 to 60 degrees, the electroforming speed is 0.05 g/h and pH value of electrolytic solution is between 7.0 to 7.5.

The ingredient contents of LJJAS compounding agent in the preferred embodiment of this invention are as follows, gold salt 62-75%, antimony 0.02-0.04%, oxalic acid 24-28% and silver, copper 3.8-4.0%.

This invention has the following advantages compared to prior art:

The gold content, pH value, working temperature, replenishment volume for maintenance and stirring rate of electrolytic solution are optimized by adding LJJAS compounding agent to the electrolytic solution, setting the electroforming temperature between 50 to 60 degrees, speed at 0.05 g/h and setting the pH value of electrolytic solution between 7.0 to 7.5. Thus, the disadvantages of unfavorable and unstable matte plating, frequently arisen of shinning matte and maldistribution, weak coating capacity will be conquered. The products have the advantages of high hardness and good rigidity. The hollow gold product will reduce the thickness of gold plating and gold consumption, moreover, it will make the gold plating more effective and even. Therefore, it can achieve even distribution, strong covering capacity, thin coating, short molding time, big size, light weight and high hardness.

This invention is comprised of following steps:

1. Carving Waxwork

Physical model is made by wax according to the drawing with clear and sharp outline, subtle detail and proper scale.

2. Making Silica Molding

Cover the surface of physical model with silica and leave to dry. Then take out the physical model from the silica molding. The silica molding should has smooth surface and seam.

3. Grafting Wax

Fully inject liquid wax into the silica molding and leave to coagulate. The wax piece is obtained after peeling off the silica molding.

4. Trimming Wax

Trim the surface of wax piece carefully using a trimming pen to ensure the conformity between the wax piece and the original version.

5. Oiling

Paint the wax piece with silver oil. The products should not have the faults like granulation and leaking. The wax removal sites of identical products should have same size and good appearance.

6. Electroforming

Mix LJJAS compounding agent with electrolytic solution in the electroforming vessel and adjust the pH value of the electrolytic solution to 7.0 to 7.5. Start the electroforming vessel, raise the internal temperature to 50-60 degrees. Then put the oiled wax piece into the vessel for electroforming at the speed of 0.05 g/h.

7. Wax Removing

Put the electroformed products into steam furnace, the melted wax will be discharged from the products. There should be no remained wax in the products.

8. Quality Inspection

Products should pass the inspections of damages, uneven surface or granules before they go out.

Claims

1. A processing technique for hard pure gold accessories, including carving waxwork, making silica molding, grafting wax, trimming wax, oiling, electroforming, wax removing and quality inspection, characterized in that LJJAS compounding agent was added to the electrolytic solution, the electroforming temperature is between 50 to 60 degrees, the electroforming speed is 0.05 g/h and pH value of electrolytic solution is between 7.0 to 7.5.

2. The processing technique for hard pure gold accessories according to claim 1, characterized in that the ingredient contents of LJJAS compounding agent are as follows, gold salt 62-75%, antimony 0.02-0.04%, oxalic acid 24-28% and silver, copper 3.8-4.0%.

3. According to claim 1 or 2 processed hard pure gold accessories.