Glass-ceramic article, process for its production and thermally crystallizable glass
US4786617A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 3, 1988 |
| Grant date | Nov 22, 1988 |
| Priority date | — |
| Expiry date | Mar 3, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C10/16
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
This invention relates to the preparation of glass-ceramic articles in which potassium fluorrichterite and/or a related fluormica constitutes the predominant crystal phase(s). The precursor glasses can be crystallized in situ very rapidly and exhibit very little thermal deformation during the crystallization heat treatment. The base glasses are essentially free of Li.sub.2 O and consist essentially, expressed in terms of weight percent on the oxide basis, of: ______________________________________ SiO.sub.2 61-70 Na.sub.2 O 0.5-3 BaO 0-3.5 Al.sub.2 O.sub.3 2.75-7 K.sub.2 O 2.5-5.5 P.sub.2 O.sub.5 0-2.5 MgO 11-16 Na.sub.2 O + K.sub.2 O <6.8 CaO 4.75-9 F 2-3.25 ______________________________________
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.