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. 27, 2011
Filed:
Apr. 22, 2004
Tetsu Umeda, Tsukuba, JP;
Yoshio Uchida, Tsukuba, JP;
Takumi Shibuta, Ichihara, JP;
Sumitomo Chemical Company, Limited, Tokyo, JP;
Abstract
A barium titanate powder and a method for producing the same are provided. The barium titanate powder comprises a perovskite structure having a ratio c/a of 1.008 or more and ratio d/D of from 1 to 1.5, wherein 'c' is a length of the c axis, 'a' is a length of the a axis in the perovskite structure, “d” is an average particle diameter and “D” is a equivalent specific surface area diameter. The method of producing a barium titanate powder, comprises the steps of: (1) heating a mixture containing a titanium compound and a barium compound under a gas atmosphere containing a halogen at a temperature of not less than about 200° C. and less than the temperature for generation of barium titanate, (2) calcining the obtained mixture under an atmosphere containing substantially no halogen at a temperature of not lower than the temperature for generation of barium titanate.