Nippon Sheet Glass Company, Limited

Kawasaki Steel Corporation, Technical Research Division

Tetsuro Kawahara

Etsuo Ogino

Kenji Mori

Kazuhiro Doushita

Hiroyuki Inomata

Yoshifumi Kijima

Toshifumi Tsujino

Yasuhiko Sakaguchi

Hiroaki Tada

Fukuo Aratani

Hideki Okamoto

Kazuhiro Uchino

Mitsugi Yoshiyagawa

Kunio Miyata

Masato Ishizaki

A low reflection film comprising silica fine particles and a binder in a weight ratio proportion of 60:40 to 95:5 is obtained by mixing starting fine particles comprising at least non-aggregated silica fine particles with a mean particle size of 40-1000 nm and/or linear (chain-like) aggregated silica fine particles with a mean primary particle size of 10-100 nm, a hydrolyzable metal compound, water, and a solvent, hydrolyzing the hydrolyzable metal compound in the presence of the starting fine particles, and then coating the prepared coating solution onto a glass base substrate and subjecting it to heat treatment. The obtained low reflection film is a single-layer low reflection film with low reflectivity, excellent abrasion resistance, high film strength and excellent contamination removal property, and coating of the low reflection film onto glass base substrates can give low reflection glass articles.

Low-reflection glass article

A surface of a glass plate is coated with a first n-type semiconductor film which is a 50 nm-thick niobium oxide film as a primer layer. The primer layer is coated with a 250 nm-thick photocatalyst film comprising titanium oxide. Thus, an article having a photocatalytically active surface is obtained. The two coating films can be formed by sputtering. The first n-type semiconductor film as the primer layer is selected so as to have a larger energy band gap than the titanium oxide. Due to this constitution, more holes are generated near the film surface. This article can be free from the problem of conventional titanium oxide films having photocatalytic activity that it is difficult to generate many surface holes contributing to photocatalytic activity, because electrons and holes generated by charge separation recombine within the film, making it impossible to effectively heighten catalytic activity.

Article having photocatalytic activity

A conductive sinter obtained from a mixture of titanium oxide particles and 2.5% by weight niobium oxide particles is used as a target in direct current sputtering to form a photocatalytically active film mainly comprising titanium oxide on a glass substrate. The target has a surface resistance of 500 &OHgr;/&square; or lower and the sputtering is conducted while heating the substrate at 230&deg; C. The photocatalytically active film is based on an amorphous matrix. This process is free from problems of a conventional process in which a photocatalytically active titanium oxide film is deposited by reactive sputtering using titanium metal as a target. The problems are that the substrate needs to be heated to 350&deg; C. or higher and that the deposited film does not have high photocatalytic activity.

Multilayer structure and process for producing the same

Method for producing high-purity metallic silicon and apparatus therefor

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Osaka, Japan

Tetsuro Kawahara