Claims
- 1. A liquid crystal display element comprising an optical alignment layer comprising a polyimide denoted by the formula wherein A is a trivalent organic moiety, Lf is a divalent organic radical comprising at least four fluorinated carbon atoms; P is a polar group comprising a II electron system containing at least one heteroatom selected from the group N, O and S; and M is a tetravalent organic radical containing at least two carbon atoms, with no more than two carbonyl groups being attached to any one carbon atom of the tetravalent radical.
- 2. A liquid crystal display element of claim 1 wherein M comprises at least one tetravalent organic moiety of the general formula wherein X2 is independently selected from the group H, CL, F, Br, R1 and R1O—, wherein R1 is independently selected from C1-C3 perflourinated alkyl chain, C1-C3 partially flourinated alkyl chain and C1-C8 hydrocarbon chain; m is 1 or 0; and Z is selected from the group —S—, —O—, —SO2—, —CH2—, —C(CF3)2—, —C(O)—, —CH2CH2—, —NR—and a covalent bond wherein R is a C1-C4 hydrocarbon chain.
- 3. A liquid crystal display element of claim 1 wherein A is selected from the group consisting of P is selected from the group consisting of: wherein —X3 is selected from the group —N(R2)2, —CN, and —NO2, t is equal to 0-4; Lf consists essentially of:—X—(CH2)n—(CF2)p—(CH2)n—X—wherein —(CF2)p— is a straight chain or branched chain perfluoroalkyl radical, p is 4-20, X is selected from the group consisting of a covalent bond, —O—, —S— and —NR—, wherein R is selected from H and C1-C4 hydrocarbon, and n is up to 4.
- 4. A liquid crystal display element of claim 2 wherein the polyimide comprises the formula
CROSS-REFERENCE TO RELATED APPLICATION
This application is a division of application Ser. No. 08/859,404 filed May 20, 1997, now U.S. Pat. No. 6,084,057.
Government Interests
This invention was madewith United States Government support under cooperative agreement No. 70NANB4H1525 awarded by the United States Department of Commerce. The United States Government has certain rights in the invention.
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