SEALING METALLIC FOIL, TUBULAR BULB AND LUMINAIRE

摘要

PROBLEM TO BE SOLVED: To improve workability, a yield and econimical efficiency in the case of manufacturing an electric lamp and a high pressure discharge lamp to airtightly seal metallic foil in an end part of an outer peripheral vessel made of quartz glass by forming an oxidation resistant coating film composed of silicon oxide on a surface of the metallic foil. SOLUTION: An oxidation resistant coating film 2 composed of densely formed silicon oxide is formed on a surface of ribbon-like metallic foil 1. The metallic foil 1 where this oxidation resistant coating film 2 is formed on a surface is sealed in a sealing part of a tungsten halogen lamp. It is thought that oxidation of the metallic foil 1 is caused since oxygen reaches a metallic part by propagating in a fine crack caused in a surface layer part without dissolving a costly surface at sealing time, and the oxidation resistant coating film 2 is more desirably arranged on a surface of the metallic foil 1 without embedding an oxidation preventive substance in the surface of the metallic foil 1. The metallic foil 1 may be formed of metallic foil 1 such as W without being limited to Mo. A thickness of the oxidation resistant coating film is better to be about 3 to 20μm.