Non-lead sealing glasses
US5246890A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 3, 1992 |
| Grant date | Sep 21, 1993 |
| Priority date | — |
| Expiry date | Aug 3, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C8/24
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Lead-free, SnO-ZnO-P.sub.2 O.sub.5 glasses contain 25-50 mole percent P.sub.2 O.sub.5 and SnO and ZnO in amounts such that the mole ratio of SnO:ZnO is in the range of 1:1 to 5:1. Optionally, the glasses may contain up to 20 mole percent of modifying oxides including up to 5 mole percent SiO.sub.2, up to 20 mole percent B.sub.2 O.sub.3 and up to 5 mole percent Al.sub.2 O.sub.3, as well as one or more crystallization promoters selected from 1-5 mole percent zircon and/or zirconia and 1-15 mole percent R.sub.2 O. The glasses are particularly useful as sealing glass frits in sealing material to join component parts in articles such as cathode ray tubes. The sealing glass material may contain mill additions to reduce the effective coefficient of thermal expansion in a seal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.