Glass with high specific rigidity for recording medium
US6329309A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 14, 1999 |
| Grant date | Dec 11, 2001 |
| Priority date | — |
| Expiry date | Sep 14, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/8404
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Oxynitride glass whose composition is represented by Al--Si--O--N or M--Al--Si--O--N (where M denotes Ca, Mg, or rare earth element), wherein the content of O and N as non-metallic components is in the range of 0 eq %<N.ltoreq.30 eq %, with O+N=100 eq %, the content of M, Al, and Si as metallic components is in the range of 20 eq %.ltoreq.Al.ltoreq.30 eq % and 70 eq %.ltoreq.Si.ltoreq.80 eq %, respectively, with Al+Si=100 eq % (if M does not exist) and the content of M, Al, and Si as metallic components is within the hatched area in the composition diagrams shown in FIGS. 1 to 3, if M is Ca, Mg, or rare earth metal, or within the hatched area in the composition diagrams shown in FIGS. 4 to 8, if the content of N is in the range of 5 eq %.ltoreq.N.ltoreq.25 eq %. This glass is superior in specific rigidity and fabricability. It contains nitrogen in a controlled amount so that it has improved specific rigidity without its specific gravity increasing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.