Forming method of gold layer

Abstract

Abstract PURPOSE:To make the gold layer formed superior in corrosion resistance by forming a primary gold layer on the object article, firmly bonding the same through heating by way of a sinter layer then applying a secondary gold layer. CONSTITUTION:A primary gold plating layer 10 of thicknesses 0.5-1.5mu is formed to the surface of the object article composed of a metal outer ring 1 and lead wires 6, 7, 8. Thence, it is heated for 3-10min. at 300-450 deg.C in a neutral atmosphere and this causes part of the primary gold plating layer to enter the crystal grains of the metal outer ring 1 and lead wires 6, 7, 8, thereby forming a sinter layer 11 and resulting in increased adhesion force and disappearance of pinholes, etc. Thence, a secondary gold plating layer 12 of thicknesses 1-5mu is formed on the primary gold layer 10 to make the total tickness of the plating layer specified 1.27-5.08mu. By this method, the gold layer of superior corrosion resistance is formed.

Inventors

• 👤 Masao Nishiyama
• 👤 Junichi Okada
• 👤 Kiyoetsu Fukui
• 👤 Shigeo Ando
• 👤 Yukio Hayakawa

Bibliographic Details