Gas-filled glass beads and method of making
US4547233A · kind A · utility
46Cited by
4References
15Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 9, 1984 |
| Grant date | Oct 15, 1985 |
| Priority date | — |
| Expiry date | May 9, 2004 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC06B23/003
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method of producing gas filled hollow glass beads comprises the steps of: PA0 i. manufacturing hollow glass beads having an alkali content of at least 20% calculated as weight per cent of oxide in the bead, PA0 ii. exposing the beads to an acidic treatment medium, for example HCl, HNO.sub.3, H.sub.2 SO.sub.4, SO.sub.2, SO.sub.3, to reduce the alkali content of the beads to not more than 15%, and PA0 iii. causing gas to diffuse into the beads.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.