Imperial Chemical Industries Limited

Hewlett-packard Development Company, L.P.

Michael B Cinderey

John B Rose

Stephen Christopher Kitson

Brian N Hendy

Graham W Scott

Neil Carter

Paul Gough

A liquid crystal device comprises a layer of a liquid crystal material contained between two spaced-apart cell walls with electrodes for applying an electric field across at least some of the liquid crystal material. At least one of the cell walls includes an alignment structure for inducing a desired local orientation of molecules of the liquid crystal material adjacent thereto. The liquid crystal material includes non-polymerisable low molecular weight surfactant molecules. The invention also provides a liquid crystal composition for use in the device and a method of manufacturing the device.

Liquid crystal device, compositions and method of manufacture

A mixture of two or more gases is contacted with a surface of a gas separation membrane and a gas having a different composition is removed from the vicinity of an opposite surface of the membrane, where the membrane is formed from a sulphonated polyarylsulphone or polyarylketone. The membrane may be a dense film or may be an asymmetric membrane. The process is particularly suitable for the separation of hydrogen from a hydrogen/nitrogen mixture when separation factors considerably in excess of 100 may be achieved together with an acceptable permeability. The membrane is preferably formed from a sulphonated polyarylethersulphone, for example one having repeat units of the formula ##STR1## where Ph.sup.1 is a phenylene residue and at least some of the groups Ph.sup.1 are sulphonated and n is 1 or 2 and the value can differ along the polymer chain. Divalent metal salts give membranes of high permeability which have a good separation factor.

Gas separation

Amorphous aromatic etherketone/sulphone copolymers, normally of reduced viscosity.gtoreq.0.8, containing 15 to 70 mole % (preferably 20 to 60 mole %) of repeat units of formula ##STR1## and correspondingly 85 to 30 mole % (preferably 80 to 40 mole %) of repeat units of formula ##STR2##

Aromatic etherketone/sulphone copolymers

Production of a dihydroxy arylophenone by reacting a diaryl carbonate in the presence of a fluoroalkane sulphonic acid. The diaryl carbonate is preferably diphenyl carbonate, the product so formed being 4,4'-dihydroxy-benzophenone. The sulphonic acid is preferably trifluoromethane sulphonic acid.

Production of dihydroxy arylophenones

Aromatic polyethers containing --SO.sub.2 -- and/or --CO-- groups are made by reacting (i) an equimolar mixture of a bisphenol and an aromatic dihalo compound or (ii) a halophenol, in which dihalo compound or halophenol the halogen atoms are activated by ortho or para --SO.sub.2 -- or --CO-- groups, with sodium carbonate or bicarbonate in admixture with a second alkali metal carbonate or bicarbonate the alkali metal of the second carbonate or bicarbonate being of higher atomic number than that of sodium. The amount of the second alkali metal carbonate or bicarbonate is such that there is 0.001 to 0.2 gram atom of the second alkali metal per gram atom of sodium.

Growing community of inventors

Stevenage, United Kingdom

Michael B Cinderey