Patent · US Expired

Chemically toughened pane

US5773148A · kind A · utility

77Cited by
4References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 29, 1995
Grant dateJun 30, 1998
Priority date
Expiry dateSep 29, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/315
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

This invention has as its subject a panel, preferably produced by the float process, reinforced by surface ion exchange for a long period at a temperature such that the exchanged depth is greater than 250 microns for surface compressive stresses exceeding 400 MPa, and greater than 75 microns for surface compresive stresses exceeding 700 Mpa, and the matrix of which complies with one of the following compositions, expressed in percentages by weight: PA1 SiO.sub.2 :65 to 76% PA1 Al.sub.2 0.sub.3 :1.5 to 5% PA1 MgO:4 to 8% PA1 CaO:0 to 4.5% PA1 Na.sub.2 :10 to 18% PA1 K.sub.2 O:1 to 7.5% PA1 B.sub.2 O.sub.3 :0 to 4% these elements representing at least 96% of the weight of the glass and complying, in addition, with the percentages by weight 0<CaO/CaO+MgO<0.45 and 0.05<K.sub.2 O/Na.sub.2 O+K.sub.2 O<0.35.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.