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. 11, 2003
Filed:
Sep. 14, 2000
Applicant:
Inventors:
John Michael Bradshaw, Chorley, GB;
Ian Heaton Smith, St. Helens, GB;
Ashley Carl Torr, Ormskirk, GB;
Stanley Lythgoe, Wigan, GB;
Assignee:
Pilkington, PLC, Lancashire, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C03C 3/085 ;
U.S. Cl.
CPC ...
C03C 3/085 ;
Abstract
A glass composition capable of being chemically strengthened by ion-exchange within 100 hours to provide a glass with a surface compressive stress of greater then 400 MPa and an ion-exchange depth greater then 200 microns comprising: SiO 58% to 70% (by weight), Al O 5% to 15%, Na O 12% to 18%, K O 0.1% to 5%, MgO 4% to 10%, CaO 0% to 1% with the provisos that the total of the Al O and MgO is in excess of 13%, the total of the amounts of Al O plus MgO divided by the amount of K O is at least 3 and that the sum of the amounts of Na O, K O and MgO is at least 22%.