Machinable glasses
US4111708A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 6, 1978 |
| Grant date | Sep 5, 1978 |
| Priority date | — |
| Expiry date | Jan 6, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C10/0027
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention relates to glass articles which have compositions within the Li.sub.2 O-ZnO-PbO-B.sub.2 O.sub.3 -SiO.sub.2 -TiO.sub.2 -Al.sub.2 O.sub.3 system, which exhibit a dense white opal appearance, and which have good machinability characteristics. The latter property enables the articles to be sawed and drilled with hand tools without spalling or breakage and, in addition, to be polished to a relatively high gloss. The glasses are rendered opaque by their spearation into a lead oxide rich phase and a B.sub.2 O.sub.3 -SiO.sub.2 rich phase. The glasses may be converted to glass-ceramic materials, either before or after machining, if desired.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.