Ultra-high-index glass microspheres and products made therefrom
US4192576A · kind A · utility
51Cited by
13References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 20, 1978 |
| Grant date | Mar 11, 1980 |
| Priority date | — |
| Expiry date | Nov 20, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S501/901
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Glass microspheres having an index of refraction of 2.7 or higher are prepared by (1) forming the microspheres from compositions based principally on 65-85 weight-percent Bi.sub.2 O.sub.3 and 5-35 weight-percent TiO.sub.2, and (2) rapidly heating the microspheres after they have been initially formed to cause an internal structural rearrangement that raises their index. Such microspheres are useful to form retroreflective products having superior properties and a more simplified construction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.