Patent ID: 7473448

Claim:
A display comprises a support bearing at least one conductive layer, an electrically modulated imaging layer comprising a diacrylate or diepoxide with positive birefringence, and an orientation layer, wherein said orientation layer comprises a photoalignable material comprising a photoactive stilbazolium-containing polymer of formula I that demonstrates a quantum efficiency of Φ˜1 at wavelengths greater than 365 nm: wherein, M a , M b , M c are monomer units making up said polymer; x and y and z are mole fractions of said monomer units M a , M b , M c , respectively, wherein in each case 0<x≦1; 0≦y<1; 0≦z<1; S a and S b are spacer units; Z a is a stilbazolium unit which can undergo photochemical isomerization/dimerization reactions; Z b is a stilbazole unit, n is from 4 to 10,000, wherein Z a has the general formula III-A or III-B: wherein A 1 and A 2 each individually signify 1,4-phenylene, which is unsubstituted or substituted with halogen, cyano and/or nitro and in which 1 or 2 CH groups are replaced by nitrogen, 2,5-thiophenediyl, 2,5-furanylene, trans-1,4-cyclohexylene, trans-1,3-dioxane-2,5-diyl or 1,4-piperidyl, 1,4- or 2,6-naphthylene, or 4,4′-biphenylene; rings A 3 and A 4 each individually signify 1,4-phenylene in which 1 or 2 CH groups of either one is replaced by nitrogen; wherein each ring is unsubstituted or substituted with halogen, cyano and/or nitro and in which 1 or 2 CH groups can be replaced by 2,5-thiophenediyl, 2,5-furanylene, 1,4- or 2,6-naphthylene; Z 1 , Z 2 and Z 3 each independently signify a single covalent bond, —CH 2 CH 2 —, —O—, —COO—, —OOC—, —NHCO—, —CONH— —OCH 2 —, —CH 2 O—, —C≡C—, —(CH 2 ) 4 —, —O(CH 2 ) 3 —, —(CH 2 ) 3 O— or the trans form of —OCH 2 —CH═CH—, —CH═CHCH 2 O—, —(CH 2 ) 2 —CH═CH— or —CH═CH(CH 2 ) 2 —; p and q each independently signify 0 or 1; R 1 signifies an electron pair, H or an alkyl group of from 1 to 12 carbon atoms, R 2 and R 3 each independently signify hydrogen, halogen, cyano, alkyl with 1 to 12 carbon atoms which is optionally substituted with fluorine and in which: optionally 1 or 2 non-adjacent —CH 2 — groups can be replaced by oxygen, —COO—, —OOC—, —CO— and/or —CH═CH—; X-signifies a charge balancing monovalent anion which may be a separate moiety, such as Cl ═ , Br ═ , I ═ , PF 6 ═ , BF 4 ═ , and CH3SO 4 ═ or part of R 1 .