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:
Dec. 03, 1991
Filed:
Mar. 15, 1989
Figaro Engineering, Inc., Osaka, JP;
Abstract
An exhaust gas sensor containing BaSnO.sub.3 or the like and a process for producing the sensor. The BaSnO.sub.3 is made free of segregation and adapted to have acid-base strength of at least 6.8 as determined with Hammett's indicator. Causes to reduce the acid-base strength of the BaSnO.sub.3 includes presence of Si and B, and causes to increase the acid-base strength include addition of Mg or Ca. The desired BaSnO.sub.3 can be prepared by precipitating BaSnO.sub.3 hydrous crystals while preventing introduction of Si and B thereinto especially with use of a container lined with a synthetic resin to prevent introduction of Si and B from the container, adding Mg or Ca to the precipitate, and thermally decomposing the precipitate.