The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 21, 1993
Filed:
Dec. 12, 1989
Tokinori Agou, Yamaguchi, JP;
Hiroaki Nakagawa, Yamaguchi, JP;
Mitsui Petrochemical Industries, Ltd., Tokyo, JP;
Abstract
A high light-transmissive dust-proof body equipped with a holding frame to be mounted on a mask substrate and a transparent light-transmissive film mounted on the holding frame, wherein the light-transmissive film comprises an inorganic film having a thickness of 0.2 .mu.m to less than 10 .mu.m and transmitting light having wavelengths of 240 to 500 nm at an average light transmittance of at least 85%, wherein the light-transmissive film forms (i) a three-layer structure of a low refractive index layer/high refractive index layer/base layer, or (ii) a five-layer structure comprising a low refractive index layer/high refractive index layer/base layer/high refractive index layer/low refractive index layer, the high refractive index layer being an inorganic layer and the low refractive index layer being an organic polymer.