| abstract |
(57) The present invention relates to a compound of the formula (I): wherein M 1 and M 2 represent homo- and / or copolymeric monomer units; x and y are 0 <x ≦ 1 and 0 Represents the molar fraction of the comonomer, ≦ y <1 and x + y = 1; p represents 4 to 30,000; S 1 and S 2 represent spacer units; Q 1 has the formula: -A- ( Z 1 -B) represents a structural unit of z- Z 2 (IIa); Q 2 represents a structural unit of the formula: -A- (Z 1 -B) z -R 1 (IIb); Each independently represents pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl or optionally substituted 1,4- phenylene; Z 1 and Z 2, each independently, single covalent bond, -CH 2 -CH 2 -, - CH 2 O -, - OCH 2 -, - CO R -, - RNCO -, - COO- or an -OOC-; R represents hydrogen or lower alkyl; R 1 is hydrogen, in each case, having 1 to 12 carbon atoms, optionally Z represents 0 or 1; C represents a photochemically dimerizable coumarin or quinolinone derivative; and m and n are substituted with each other; Each of which independently represents 0 or 1), which is a coumarin derivative having a photoreactive ethene group. The invention also relates to their use as liquid crystal alignment layers. |