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. 13, 1996
Filed:
Sep. 18, 1995
Masami Kaneyoshi, Fukui-ken, JP;
Shigeru Sakai, Fukui-ken, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
Proposed is a method for the preparation of a rare earth oxide powder consisting of particles having a globular particle configuration to be suitable as a base material of phosphors. The method comprises the steps of mixing an aqueous solution of a rare earth salt and an aqueous alkaline solution, e.g., ammonia water, to precipitate a rare earth hydroxide which is collected, washed with water and calcined to be converted into the oxide powder. Characteristically, the precipitation reaction of the rare earth hydroxide is carried out in the presence of a nitrogen-containing chelating agent such as triethanolamine in the aqueous medium in a controlled amount.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile