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:
Aug. 11, 1992
Filed:
Dec. 19, 1990
Seizi Yamazaki, Matsusaka, JP;
Kensuke Makita, Mie, JP;
Yasuo Moriguchi, Matsusaka, JP;
Katsuto Tanaka, Matsusaka, JP;
Central Glass Company, Limited, Ube, JP;
Abstract
The invention relates to a sol-gel method for forming a metal oxide film, e.g. TiO.sub.2 film or TiO.sub.2 -SiO.sub.2 film, on a substrate by applying a solution of at least one metal alkoxide to the substrate to form a sol film on the substrate, drying the sol film to cause it to turn into a gel film by hydrolysis and baking the gel film. According to the invention the viscosity of the metal alkoxide solution is adequately increased, preferably to 3-30 cP at 20.degree. C., by the addition of a combination of a hydroxypropyl cellulose of which 2 wt % aqueous solution has a viscosity of 150-400 cP at 20.degree. C. and another hydroxypropyl cellulose of which 2 wt % aqueous solution has a viscosity of 6-10 cP at 20.degree. C. Metal oxide films formed by this method are free from minute cracks and excellent in optical characteristics and durability. By this method it is possible to form a metal oxide film as thick as about 300 nm without repeating the application of the alkoxide solution to the substrate.