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:
Feb. 19, 2013
Filed:
Feb. 04, 2010
Kensuke Nagai, Tokyo, JP;
Tetsuya Nakashima, Tokyo, JP;
Kei Maeda, Tokyo, JP;
Asahi Glass Company, Limited, Tokyo, JP;
Abstract
A glass composition for substrates excellent in productivity is provided by lowering the high temperature viscosity while securing characteristics and quality required for FPD substrates, particularly for PDP substrates. A glass composition for substrates, which is characterized by comprising, as represented by mass% based on oxides, from 55 to 75% of SiO, from 5 to 15% of AlO, from 4 to 18% of MgO, from 3 to 12% of CaO, from 4 to 18% of SrO, from 0 to 20% of BaO, from 6 to 20% of NaO+KO, from 0.5 to 6% of ZrOand from 18 to 25% of MgO+CaO+SrO+BaO, as a glass matrix composition, and containing from 0.001 to 0.6% of SO, and which is further characterized in that when the viscosity is represented by η, the temperature satisfying logη=2 is at most 1,545° C. and the devitrification temperature is at most the temperature satisfying logη=4, the thermal expansion coefficient is from 75×10to 90×10/° C., the specific gravity is at most 2.8, and the glass transition point is at least 600° C.