Liquid crystal mixture
US4299720A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 1979 |
| Grant date | Nov 10, 1981 |
| Priority date | — |
| Expiry date | Nov 9, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B5/24
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A liquid crystal mixture intended for electrooptical displays having no polarizers, consisting of: PA0 a nematic liquid crystal as the host phase; PA0 an optically active additive to give the host phase a cholesteric structure; and PA0 at least one pleochroic anthraquinone dye as the guest phase dissolved in the host phase, said anthraquinone dye having the formula: ##STR1## wherein R.sup.2, R.sup.3 and R.sup.4 are the same or different substituents and are selected from the group consisting of hydrogen, hydroxyl, amino, and short-chain N-monoalkylamino substituents; Y represents halogen, alkyl or alkoxy groups each with 1-16 carbon atoms, amino, alkylamino groups with 1-16 carbon atoms in the alkyl portion, nitro, or hydroxyl group; X represents halogen, amino or the group R.sup.5, wherein R.sup.5 is an alkyl group with 1-18 carbon atoms, an alkyl chain with 1-18 carbon atoms that is interrupted with one or two oxy groups or a group having the formula: EQU --(CH.sub.2).sub.p --(O--C.sub.2 H.sub.4).sub.r --O--R.sup.6 wherein p is an integer from 1 to 6, r is either zero or an integer from 1 to 6, and R.sup.6 is an alkyl group with 1-6 carbon atoms; the symbol A represents a 5- or 6…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.