The Secretary of State for Defence in Her Britannic Majesty's Government

Qinetiq Limited

Merck Patent Gesellschaft MIT Beschrankter Haftung

Other

The Secretary of State for Defence

The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland

The Secretary of State for Defence in Her Brittanic Majesty's Government

The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland Defence Evaluation Research Agency

The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britian and Northern Ireland of Defence Evaluation and Research Agency

The Secretary of State for in Defence in Her Brittanic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland

The Secretary of State for for Defence in Her Britannic Majesty's

The Secretary of State for Defence in Her Britannic Majesty'3 S

The Secretary of State for Defence in Her Britannic Majesty's a

Michael Hird

Kenneth J Toyne

John William Goodby

George W Gray

Damien Gerard McDonnell

David Lacey

Sally Elizabeth Day

Amarjit Kaur Samra

Alexander J Seed

Chu Chuan Dong

David Coates

Edward P Raynes

Kenneth J Harrison

Maurice Stanley

Andrew John Slaney

Victoria Minter

Simon John Cross

Damien Gerad McDonnel

Ian Charles Sage

Volker Reiffenrath

Joachim Krause

Andreas Wachtler

Simon Greenfield

John Clifford Jones

Ulrich Finkenzeller

John A Jenner

Robert Andrew Lewis

Robert Andrews Lewis

Georg Weber

Thomas Geelhaar

Timothy Jonathan Phillips

Lawrence Kam Chan

Rachel P Tuffin

David Richard Beattie

Stephen J Cowling

Neil Gough

Stephen John Lock

Paul Hindmarsh

Guirec Y Cosquer

Benjamin Ross Carrick

Stephane Trombotto

Robert D C Richards

Liquid crystal compounds of Formula (I) for use in liquid crystal devices contains a dioxatetralin unit within the mesogenic liquid crystal core. The dioxatetralin unit may be located at any position within the mesogenic core of the liquid crystal compound, either at the terminus of the liquid crystal core or alternatively substantially in the middle of the liquid crystal core. The compounds of the invention exhibit fast switching and may be used in liquid crystal mixtures for particular use in imaging or display media, such as monitors or televisions.

Compounds for use in liquid crystal devices

The use of a mesogenic compound having a terminal end chain comprising carbon, oxygen, or sulphur, which has at least one pendent Calkyl, Calkoxy or a cycloalkyl ring, arranged no more than 6 atoms from the end of the chain either decreasing the melting point, increasing the clearing point, increasing the speed of switching and/or increasing the tilt angle of a liquid crystal mixture. Examples of such compounds are of formula (I)  

Liquid crystal compounds with branched or cyclic end groups

Liquid crystalline compounds containing a biphenyl core

High transverse dipole moment aryl compounds

An electroclinic device having two spaced cell walls each bearing electrode structures and treated on at least one facing surface with an alignment layer, a layer of a smectic liquid crystal material enclosed between the cell walls, where the liquid crystal material contains one or more of the compounds described by formula I as defined in the specification.

Liquid crystal compounds, mixtures and devices

Liquid crystal compounds of formula (I) are described, where formula (I) is given as R,&mdash;A&mdash;(X),&mdash;(B),&mdash;R,where A is selected from naphthyl, fluorinated naphthyl, brominated naphthyl, B is selected from phenyl, methylated phenyl, brominated phenyl, fluorinated phenyl, thiophene, pyrimidine and pyridine. R,and R,are independently selected from alkyl, alkoxy, akynyl, thioalkyl, Br, CN, SCN, NCS, perfluoroalkyl, perfluoroalkoxy and hydrogen, X is selected from C&equiv;C, COO and C&equiv;C, m is 0 or 1, n is 0 or 1 where m is 1 and n is 0 where m is 0; provided that where A is naphthyl, n is 1 and m is 0 then B is selected from methylated phenyl, brominated phenyl, thiophene, pyrimidine and pyridine; and further provided that where A is naphthyl, X is C&equiv;C, m is 1 and n is 1, then B is selected from thiophene, pyrimidine and pyridine. Also described are liquid crystal compounds suitable for inclusion in devices utilizing pretransitional characteristics of liquid crystalline materials in the isotropic phase and described by formula (II): R,&mdash;J&mdash;(Y),&mdash;(Z),&mdash;R,, where J is selected from nathhyl, fluorinated naphthyl, brominated naphthyl, Z is selected from phenyl, methylated phenyl, brominated phenyl, fluorinated phenyl, thiophene, pyrimidine and pyridine, R,and R,are independently selected from alkyl, alkoxy, alkynyl, thioalkyl, Br, CN, SCN, NCS, perfluoroalkyl, perfluoroalkoxy and hydrogen, Y is selected from C&boxH;C, COO and C&boxH;C, p is 0 or 1, q is 0 or 1 where p is 1 and q is 0 where p is 0.

Naphthyl organic compounds

An electoclinic device having two spaced cell walls each bearing electrode structures and treated on at least one facing surface with an alignment layer, a layer of a smectic liquid crystal material enclosed between the cell walls, where the liquid crystal material contains one or more of the compounds described by formula I as defined in the specification.

The synthesis of novel compound (I) is described: 5-bromo-2-iodopyrimidine may be used for the synthesis of a range of chemical compounds both known and novel. The synthesis of a number of novel liquid crystalline compounds is described.

Pyrimidine compounds

Chiral compounds

Liquid crystal mixtures and devices

##STR1## The invention describes liquid crystalline compounds or formula (I), where A, D and G are independently selected from phenyl, thiophene, hydrogenated phenyl, chlorinated phenyl and fluorinated phenyl, B and E are independently selected from a single bond C.dbd..notident.C. C.tbd.C.C00, azoxy and diazo, k and m are independently selected from 1 and 0, such that m+n is 1 or 2, and R.sub.1 and R.sub.2 are independently selected from R, R0, alkynyl, thioalkyl, hydrogen, CN, NCS and SCN; provided that at least one of R.sub.1 and R.sub.2 is selected from CN, NCS and SCN and that at least one of A, D and G is phenyl; and excluding where at least one of R.sub.1 and R.sub.2 is independently selected as CN and one of A, D or G is not thiophene, and where m is 0, A, and D are phenyl, B is a single bond and only one of R.sub.1 or R.sub.2 is NCS. Also described are compounds suitable for inclusion in a device utilizing pretransitional characteristics of liquid crystalline materials in the isotropic phase, of general formula (II) where J and Y are independently selected from phenyl, thiophene, hydrogenated phenyl, chlorinated phenyl and fluorinated phenyl, X is selected from C.dbd..notident.C. C.tbd.C.COO azoxy and diazo, k is 1 or 0 and R.sub.3 and R.sub.4 are independently selected from R, RO, alkynyl, thioalkyl, hydrogen, CN, NCS and SCN; provided that at least one of R.sub.3 and R.sub.4 is selected from CN, NCS and SCN and that at least one of J and Y is phenyl.

Anisotropic organic compounds

Chiral cyclohexyl compounds

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Hull, United Kingdom

Michael Hird