Liquid crystal display devices
US4032219A · kind A · utility
37Cited by
2References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 17, 1975 |
| Grant date | Jun 28, 1977 |
| Priority date | — |
| Expiry date | Oct 17, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2202/043
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A liquid crystal guest-host display device includes a dye dissolved in the liquid crystal material. The invention is characterized in that the dye comprises three colored dye compounds mixed together to provide gray in the absence of an applied electric field. The compounds may be Sudan Black, Sudan Red and .beta.-carotene. The liquid crystal material preferably includes at least one 4'-alkyl- or -alkoxy-4'-cyanobiphenyl compound.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.