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:
May. 02, 1995
Filed:
Sep. 22, 1993
Patricia A Morris, Wilmington, DE (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A process is disclosed for treating a crystal of MTiOXO.sub.4 which has crystal structure deficiencies of M and O, wherein M is selected from the group consisting of K, Rb, Tl and NH.sub.4 and mixtures thereof and X is selected from the group consisting of P, As and mixtures thereof, which includes the step of heating said crystal in the presence of a mixture of MTiOXO.sub.4 and at least one inorganic compound of one or more monovalent cations selected from the group consisting of Rb+, K+, Cs+ and Ti+ (said inorganic compound(s) being selected to provide a source of vapor phase monovalent cation and being present in an amount sufficient to provide at least a 0.1 mole % excess of the monovalent cation in relation to the M in the MTiOXO.sub.4 in said mixture) at a temperature of from about 400.degree. C. to 950.degree. C. and a pressure of at least 14 psi, and in the presence of a gaseous source of oxygen for a time sufficient to decrease the optical damage susceptibility of said crystal.