Glass powders for dental glass ionomer cements
US4900697A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 1988 |
| Grant date | Feb 13, 1990 |
| Priority date | — |
| Expiry date | Jan 29, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2111/00836
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
A fluoroaluminosilicate glass powder for dental glass ionomer cements has a specific gravity of 2.4 to 3.5 and a mean particle size of 0.02 to 10 .mu.m, contains in its components 20 to 50% by weight of SiO.sub.2, 20 to 40% by weight of Al.sub.2 O.sub.3, 15 to 40% by weight of SrO, 1 to 20% by weight of F.sub.2 and 0 to 15% by weight of P.sub.2 O.sub.5 on the converted oxide basis, and is substantially free from alkali metal ions such as Li, Na, K, Rb and Cs ions, and Be, Mg (and Ca) and Ba ions of alkali earth metal ions. For further improvements in physical properties, 100 parts by weight of the glass powder are surface-treated with 0.01 to 5 parts by weight of an acid and/or a fluoride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.