Patent · US Expired

Glass substrate for magnetic disk

US5900296A · kind A · utility

48Cited by
8References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 18, 1996
Grant dateMay 4, 1999
Priority date
Expiry dateApr 18, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/315
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A glass substrate for magnetic disks, obtained by chemical strengthening treatment of a glass consisting essentially of from 50 to 65 wt % of SiO.sub.2, from 5 to 15 wt % of Al.sub.2 O.sub.3, from 2 to 7 wt % of Na.sub.2 O, from 4 to 9 wt % of K.sub.2 O, from 7 to 14 wt % of Na.sub.2 O+K.sub.2 O, from 12 to 25 wt % of MgO+CaO+SrO+BaO, and from 1 to 6 wt % of ZrO.sub.2.

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