Patent US4637897A successfully refreshed from Google Patents.
US4637897A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nematic compounds
Assignee: Merck Patent GmbH
•
Filing: 1984-08-06
•
Granted: 1987-01-20
•
Expires: 2004-08-06
Abstract
Abstract Nematic compounds with a negative DC antisotropy, characterized by the formula I ##STR1## in which m=1 or 2, r is zero or 1 and m+r=1 or 2, and R 1 and R 2 are identical or different and are selected from alkyl and alkoxy groups each having 1-12 carbon atoms in a straight or branched chain, which may be chiral, Z is a bridge member selected from a single bond and the groups of the formulae --CH 2 CH 2 --, --OCH 2 --, --O--CO-- or --CO--O--, one of the groups X and Y is selected from fluorine, chlorine, bromine and cyano and the other of the groups X and Y is selected from hydrogen, fluorine, chlorine, bromine and cyano, with the proviso that m=r=1 if X and Y are both cyano, are suitable as components for liquid crystal mixtures having an overall negative DC anisotropy, such as are required in particular for electro-optical displays of the type of guest/host displays or homotropic-nematic displays.
Inventors
- 👤 Stephen M. Kelly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:38
CPC Classifications
C; C07; C07C; C07C255/00; C07C25/00; C07C25/18; C07C43/00; C07C43/02; C07C43/20; C07C43/225; C07C45/00; C07C45/45; C07C45/46; C07C49/00; C07C49/76; C07C49/84; C07C53/00; C07C53/38; C07C53/44; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/08; C09K19/30; C09K19/3001; C09K19/3028; C09K19/3066; C09K19/3068
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
86 words
In a liquid crystalline dielectric comprising at least two liquid crystalline compounds, the improvement wherein at least one of these compounds is a nematic compound with a negative dielectric anisotropy of the formula ##STR12## R 1 and R 2 are identical or different and each is alkyl of 1-12 carbon atoms, Z is a bridging group which is --CH 2 CH 2 --, --OCH 2 --, --O--CO-- or --CO--O-- and, one of X and Y is flourine, chlorine, bromine or cyano and the other is hydrogen.
Claim 2
Dependent Claim
86 words
In a liquid crystalline dielectric comprising at least two liquid crystalline compounds, the improvement wherein at least one of these compounds is a nematic compound with a negative dielectric anisotropy of the formula ##STR12## R 1 and R 2 are identical or different and each is alkyl of 1-12 carbon atoms, Z is a bridging group which is --CH 2 CH 2 --, --OCH 2 --, --O--CO-- or --CO--O-- and, one of X and Y is flourine, chlorine, bromine or cyano and the other is hydrogen.
Claim 3
Dependent Claim
59 words
A compound of the formula ##STR13## wherein R 1 and R 2 are identical or different and each is alkyl of 1-12 carbon atoms, Z is a bridging group which is --CH 2 CH 2 --, --OCH 2 --, --O--CO-- or --CO--O-- and, one of X and Y is fluorine, chlorine, bromine or cyano and the other is hydrogen.
Claim 4
Dependent Claim
59 words
A compound of the formula ##STR13## wherein R 1 and R 2 are identical or different and each is alkyl of 1-12 carbon atoms, Z is a bridging group which is --CH 2 CH 2 --, --OCH 2 --, --O--CO-- or --CO--O-- and, one of X and Y is fluorine, chlorine, bromine or cyano and the other is hydrogen.
Claim 5
Dependent Claim
14 words
A dielectric of claim 1, wherein R 1 or R 2 is straight chained.
Claim 6
Dependent Claim
16 words
A dielectric of claim 1, wherein R 1 or R 2 is a chiral branched group.
Claim 7
Dependent Claim
14 words
A dielectric of claim 1, wherein said nematic compound is of the formula ##STR14##
Claim 8
Dependent Claim
14 words
A dielectric of claim 1, wherein said nematic compound is of the formula ##STR15##
Claim 9
Dependent Claim
14 words
A dielectric of claim 1, wherein said nematic compound is of the formula ##STR16##
Claim 10
Dependent Claim
14 words
A dielectric of claim 1, wherein said nematic compound is of the formula ##STR17##
Claim 11
Dependent Claim
13 words
A dielectric of claim 1, wherein X is fluoro and Y is H.
Claim 12
Dependent Claim
18 words
A dielectric of claim 1, wherein Z is --CH 2 CH 2 --, --OCH 2 -- or --O--CO--.
Claim 13
Dependent Claim
14 words
A dielectric of claim 1, wherein R 1 is straight chain C 2-8 -alkyl.
Claim 14
Dependent Claim
9 words
A compound of claim 2 of the formula ##STR18##
Claim 15
Dependent Claim
9 words
A compound of claim 2 of the formula ##STR19##
Claim 16
Dependent Claim
9 words
A compound of claim 2 of the formula ##STR20##
Claim 17
Dependent Claim
20 words
In an electro-optical display element comprising a liquid crystalline dielectric, the improvement wherein the dielectric is one of claim 1.
Claim 18
Dependent Claim
18 words
A electrooptical display element of claim 15 which is a guest/host display element or a homotropicnematic display element.
Claim 19
Dependent Claim
15 words
A liquid crystalline dielectric of claim 7 wherein one of X and Y is F.
Claim 20
Dependent Claim
15 words
A liquid crystalline dielectric of claim 1 wherein one of X and Y is F.
Claim 21
Dependent Claim
9 words
A compound of claim 2 of the formula ##STR21##
References Cited (Backward Citations)
US4368135A
Cited
US4357078A
Cited
US4400061A
Cited
US4400293A
Cited
US4439015A
Cited
EP0058512A1
Cited
DE3237367A1
Cited
EP0084194A1
Cited
US4514317A
Cited
US4479885A
Cited
US4480117A
Cited
US4393258A
Cited
US4512636A
Cited
EP0103681A1
Cited
DE3335550A1
Cited
EP0107116A1
Cited
GB2134110A
Cited
DE3317597A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-01-19 | 1990-07-21 | 1991-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-19 | 1994-07-21 | 1995-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-19 | 1998-07-21 | 1999-01-20 | $7700.00 | Window Closed / Lapsed |