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:
Oct. 04, 2011
Filed:
Feb. 24, 2009
Joseph James Mcintosh, Painted Post, NY (US);
Joseph James McIntosh, Painted Post, NY (US);
Corning Incorporated, Corning, NY (US);
Abstract
Isopipes () for making a glass or a glass-ceramic using a fusion process are provided. The isopipes are made from a silicon nitride refractory material that is: (a) produced in block form in an atmosphere having a pOof less than 0.1 using less than 10 weight percent of one or more sintering aids, (b) machined into an isopipe configuration, and (c) exposed to a partial pressure of oxygen equal to or greater than 0.1 for a period of time and at a temperature sufficient to form a SiOlayer () which exhibits substantially only a passive oxidation mechanism. The SiOlayer () serves as a protective barrier for further oxidation of the silicon nitride during use of the isopipe (). The isopipes () exhibit less sag during use than isopipes composed of zircon.