Exterior parts for watches

Abstract

Abstract PURPOSE:To provide parts having superior corrosion and wear resistances, adhesion and high ornamental value by carrying out two-color finishing with a golden gold alloy film and a hard titanium oxide film having a blue color tone. CONSTITUTION:A stainless steel (SUS 304) watchcase 1 is coated with >=23-k. Au-Ni-In alloy film 2 by electroplating. The coated case 1 is set in a vacuum chamber and subjected to ionic bombardments by impressing a prescribed voltage in gaseous Ar to clean the surface of the case 1. The vacuum chamber is then returned to a prescribed pressure by exhausting the gaseous Ar, oxygen is introduced to a prescribed pressure and plasma is generated by impressing a prescribed voltage to coat the case 1 with a blue titanium oxide film 3 by ion plating. The part of the case 1 on which the blue film 3 is left is masked with an org. resist 4, the resist 4 is baked and the film 3 is removed except the masked part with a removing soln. contg. a strong acid. The resist 4 is finally removed with an org. solvent and a two-color finished case is obtd.

Inventors

• 👤 Kiyohiro Imai
• 👤 今井　清博

Bibliographic Details