Displaytech, Inc.

Citizen Finedevice Co., Ltd.

Citizen Finetech Miyota Co., Ltd

William N Thurmes

Michael D Wand

Kundalika M More

David M Walba

Xin-Hua Chen

Rohini T Vohra

Xin Hua Chen

Neil Gough

Uwe Muller

Daniel J Dyer

Peter Cobben

Sean D Monahan

Michael J O'Callaghan

Cory Pecinovsky

Christopher Gabriel

Brion C Koprowski

Kundalika Mor E

New classes of thiadiazole and oxadiazole compounds for use in LC mixtures are disclosed. In an embodiment, the new classes of thiadiazoles and oxadiazoles comprise at least one phenyl ring attached to the heterocyclic ring, where no alkyl, alkenyl or alkynyl tails are attached to the phenyl ring, but one alkyl, alkenyl or alkynyl tail is attached to the other end of the molecule, and a fluoro or cyano group appears in the para position of the phenyl ring. These compounds are disclosed as being effective at inducing smectic A phases in liquid crystal mixtures, particularly in liquid crystal mixtures also possessing a smectic C phase, more particularly in materials possessing a chiral smectic C (ferroelectric) phase.

Thiadiazoles or oxadiazoles possessing one alkyl, alkenyl or alkynyl tail and a 4-fluorophenyl or 4-cyanophenyl group

Ferroelectric liquid crystal compositions including organic ion pair compounds wherein image sticking is reduced or eliminated. Use of the ferroelectric liquid crystal compositions in a ferroelectric liquid crystal display device allows for rapid image refresh rates without required a DC-balancing algorithm. The organic ion pair compounds provide electrical resistivity values for the compositions that result in reduced image sticking when the compositions are used in FLC display devices.

Ferroelectric liquid crystal mixture with organic ion pair compound

The present invention provides organogermanium compounds and liquid crystal compositions comprising such a compound.

Liquid crystal compositions comprising an organogermanium compound and methods for using the same

The invention relates to chiral nonracemic liquid crystal compounds having achiral tails comprising a perfluoroalkyl terminal portion which are useful as components in liquid crystal to impart high polarization to the mixture. The materials of this invention can be combined with known liquid crystal host materials to impart improved properties. Chiral nonracemic compounds of this invention can function as additives or dopants in host materials to impart chirality into an LC material.

High polarization ferroelectric liquid crystal compositions

Compounds useful as components of LC and FLC compositions which in turn are useful in the manufacture of optical devices. Compounds of this invention have a silane tail, which can contain more than one Si. Compounds of this invention can include those with disilane tails. The invention provides LC compositions containing one or more of the silanes of this invention. Addition of one or more of the compounds of this invention to LC compositions can result in significant improvement in optical or LC properties. In particular, the compounds of this invention can significantly lower the melting point, freezing point or both of an LC composition resulting in significant improvement in device stability.

Alkyl silane liquid crystal compounds

Compounds that are useful as components in liquid crystal compositions, particularly in ferroelectric liquid crystal compositions. Compounds of the invention are rod-like molecules with a mesogenic (generally linear) core to which an alkene tail and an alkyl or alkoxy tail with a perfluoroalkyl terminal portion are bonded. Compounds of the invention can contain a variety of one, two or three ring cores, wherein the rings maybe aromatic or alicyclic. Alkenes of the invention are useful as components to improve LC properties of mixtures, for example, to lower melting point of lower freezing point, of LC compositions.

Liquid crystalline materials containing perfluoroalkyl and alkenyl tail groups

Liquid crystal compounds having a silane tail with a perfluoroalkyl terminal portion

Liquid crystal materials that exhibit bookshelf structures are provided. When these bookshelf materials are incorporated into a bistable host material, the mixture exhibits a higher switching angle and increased A to C phase transition than bistable hosts without the bookshelf material. These bookshelf materials and bistable compositions are useful in liquid crystal displays, for example.

Bookshelf liquid crystal materials and devices

A liquid crystal infrared light chopper includes a polarizer that receives and polarizes incoming infrared light, a layer of ferroelectric liquid crystal material switchable between at least two states, a pair of IR transparent, conductive substrates positioned on either side of the liquid crystal layer and an analyzer that blocks IR light of one polarization state and passes IR light of an opposite polarization state. The liquid crystal layer acts on polarized IR light by changing its polarization if the liquid crystal is in a first state and by not changing its polarization if the liquid crystal is in a second state. Voltages applied to the conductive substrates drive the liquid crystal layer to one of the two states. The analyzer blocks IR light when the liquid crystal layer is in one of the states and passes IR light when the liquid crystal layer is in the second state.

Ferroelectric liquid crystal infrared chopper

This invention provides LC compositions useful as birefringent materials in electrooptic devices which exhibit zero or low negatively sloped birefringence dispersioon (e.g., exhibiting positive birefringence dispersion significantly lower than that of currently available LC compositions) or more preferably positively sloped birefringence dispersion in which birefringence of the material increases with wavelength. The invention provides compounds useful as components of LC compositions which exhibit negative birefringence where n is higher than n . The compounds of this invention are dimers of LC-like compounds in which the monomers are linked to each other through a high birefringence moiety (dimerization linker). The LC monomers consist of an LC core and one or two tail groups. Preferred monomers for this invention have low birefringence in comparison to the birefringence of the monomer linking moiety. The dimers have normal positive birefringence dispersion to have birefringence that is lower in absolute value at longer wavelengths. But since they have negative birefringence, their birefringence actually increases (i.e., goes less negative) as wavelength increases.

Mesogenic materials with anomalous birefringence dispersion and high second order susceptibility (X(2))

Cyclohexyl- and cyclohexenyl-substituted liquid crystals with low birefringence

This invention provides LC compositions useful as birefringent materials in electrooptic devices which exhibit zero or low negatively sloped birefringence dispersion (e.g., exhibiting positive birefringence dispersion significantly lower than that of currently available LC compositions) or more preferably positively sloped birefringence dispersion in which birefringence of the material increases with wavelength. The invention provides compounds useful as components of LC compositions which exhibit negative birefringence where n.sub.o is higher than n.sub.e. The compounds of this invention are dimers of LC-like compounds in which the monomers are linked to each other through a high birefringence moiety (dimerization linker). The LC monomers consist of an LC core and one or two tail groups. Preferred monomers for this invention have low birefringence in comparison to the birefrigence of the monomer linking moiety. The dimers have normal positive birefringence dispersion to have birefringence that is lower in absolute value at longer wavelengths. But since they have negative birefringence, their birefringence actually increases (i.e., goes less negative) as wavelength increases.

Mesogenic materials with anomalous birefringence dispersion and high

High birefringence liquid crystal dopants having the formula:

High birefringence liquid crystal compounds

This invention provides chiral nonracemic compounds of general formula I which are useful as components of FLC compositions in SSFLC and DHFLC devices: ##STR1## wherein Z is a C.dbd.O group or a CH.sub.2 group, R.sub.F is a partially or fully fluorinated alkyl or alkenyl group, R.sub.2 is selected from an alkyl, alkenyl or alkynyl group in which one or more CH.sub.2 groups can optionally be substituted with one or two halogen atoms or in which one or more non-neighboring CH.sub.2 can be replaced with an O, S or an alkyl silyl group, S.sub.1 (R.sub.A)(R.sub.B), in which R.sub.A and R.sub.B, independently of one another, are small alkyl or alkenyl groups having from one to six carbon atoms, * indicates the chiral carbon and where Ar can be a one, two, or three aromatic ring LC core moieties. In particular, the core can have one to three, aromatic rings which are optionally linked by linking groups including O, S, CH.sub.2 S, SCH.sub.2, CH.sub.2 CH.sub.2, CH.sub.2 O, OCH.sub.2, CH.sub.2 CO.sub.2, CH.sub.2 OCO, COO, OOC, COS, a double or a triple bond and can contain cyclohexyl cyclohexenyl rings which are optionally substituted or which contain O atoms in the ring.

Liquid crystal compounds containing chiral 2-halo-2-methyl ether and

The present invention provides liquid crystals that are diphenyldiacetylenes of the general formulas: ##STR1## where W, X, Y and Z are, independently of one another, a halogen atom, a hydrogen atom or a trihalomethyl group, T.sub.1 and T.sub.2, independently of one another can be an alkyl, alkene, alkoxy, alkenoxy, ether, thioalkyl, thioalkenyl, haloalkyl, haloalkoxy or haloalkylether groups having from three to twenty carbon atoms or a silylalkyl, silylalkenyl, silylalkoxy or silylthioalkyl group having from three to twenty-eight carbon atoms and wherein M.sub.1 and M.sub.2 can both be single bonds or one of M.sub.1 or M.sub.2 can be a trans-1,4-cyclohexylene or a --CH.sub.2 CH.sub.2 -trans-1,4-cyclohexylene.

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Longmont, CO, United States of America

William N Thurmes