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:
Jun. 02, 2026
Filed:
Sep. 27, 2021
Sumitomo Electric Industries, Ltd., Osaka, JP;
Shinji Ishikawa, Osaka, JP;
Tetsuya Haruna, Osaka, JP;
Keisei Morita, Osaka, JP;
Tatsuro Hasegawa, Osaka, JP;
Seiji Arakawa, Osaka, JP;
SUMITOMO ELECTRIC INDUSTRIES, LTD., Osaka, JP;
Abstract
A method for producing fluorine-containing silica glass is disclosed. The method includes decompression degassing which includes degassing an inside of a furnace core tube under reduced pressure while heating the inside of the furnace core tube, after inserting a porous silica glass body into the furnace core tube provided in an airtight container; fluorine adding which includes supplying a fluorine compound gas into the furnace core tube, exhausting the fluorine compound gas remaining in the furnace core tube to an outside of the furnace core tube, and first heat-treating the porous silica glass body, under reduced pressure; and second heat-treating the porous silica glass body under reduced pressure at a temperature higher than temperatures in the decompression degassing process and the fluorine adding process.