Patent ID: 6770334
Filing Date: 2004-08-03
Classification: C09K,G02B

Abstract:
A process for orienting discotic liquid crystal molecules, comprising the steps of: coating a solution of a copolymer comprising repeating units represented by the formula (I) and repeating units represented by the formula (II) on a support to form a coated layer, rubbing a surface of the coated layer to form an orientation layer; coating a solution containing discotic liquid crystal molecules on the orientation layer to orient the discotic liquid crystal molecules so that an average inclined angle of discotic planes of the discotic liquid crystal molecules is in the range of 50Â° to 90Â° and that an average direction of optical axes of the discotic liquid crystal molecules is essentially parallel to a rubbing direction of the orientation layer: in which each of R1 and R2 independently is hydrogen, a halogen atom or an alkyl group having 1 to 6 carbon atoms; M is an alkali metal ion; L1 is a divalent linking group selected from the group consisting of â€”Oâ€”, â€”COâ€”, â€”NHâ€”, an alkylene group and a combination thereof; each of L2, L3 and L4 independently is a single bond or a divalent linking group selected from the group consisting of â€”Oâ€”, â€”COâ€”, â€”NHâ€”, â€”SO2â€”, an alkylene group, an alkenylene group, an alkynylene group and a combination thereof; each of Ar1, Ar2, Ar3 and Ar4 independently is an aromatic ring, which can have a substituent group; each of m and n independently is 0 or 1; x is 10 to 95 mole %; and y is 5 to 90 mole %.