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:
Jul. 10, 1990
Filed:
Apr. 01, 1988
Sophia R Su, Weston, MA (US);
Leo F Fitzpatrick, Sandwich, MA (US);
Sheryl A Robillard, Leominster, MA (US);
GTE Laboratories Incorporated, Waltham, MA (US);
Abstract
A method of making large particle size, high purity, dense silica is described. Tetraethylorthosilicate ethanol solution is added to a 2N ammonium hydroxide solution containing silicic acid having an average particle size of about 15 micrometers to form a precipitate followed by a digestion of the precipitate in the solution. The precipitate is filtered through a screen having 45 micrometer openings and dried to form a dried powder. The dried powder is then calcined in an oxygen atmosphere followed by densifying it by heating at a temperature of about 1200.degree. C. in air to form a large particle size, high purity, dense silica.