Patent ID: 7390578

Claim:
Aryl-substituted poly-p-arylenevinylene consisting of a repeating unit of the formula (C1), in which —OC m and —OC n are alkoxy groups, m and n are integers from 2 to 6 with m+n=8, p is 1, 2 or 3 and in which R is CN, Cl, F, CF 3 , NO 2 or SO 3 Z wherein Z is a monovalent cation, or in which R is —XR 1 wherein the unit —X— represents a single bond, —O—, —S—, —CO—, —COO—, —OCO—, —SO—, —SO 2 —, —N(R 2 )— or —N(R 2 )CO—; wherein R 1 and R 2 are the same or different and constitute a straight-chain branched or cyclic C 1 -C 20 alkyl group or together a C 1 -C 20 alkylene group, in which C 1 -C 20 alkyl group or C 1 -C 20 alkylene group one or more hydrogens are optionally substituted by F or a C 4 -C 12 aryl group and/or one or more non-adjacent —CH 2 — units are optionally substituted by C 4 -C 12 arylene, —O—, —S—, —CO—, —COO—, —OCO—, —SO—, —SO 2 —, —N(R 3 )— or —N(R 3 )CO—, and where R 3 is C 1 -C 20 alkyl, or in which R is a C 4 -C 12 aryl group which may or may not be substituted, said aryl-substituted poly-p-arylenevinylene when incorporated in an active layer of an organic electroluminescent device having one or more active layers being effective to enhance the service life of said organic electroluminescent device to at least 45 h when said electroluminescent device is driven at a constant current, at an initial brightness of 200 Cd/m 2 , and at an ambient temperature of 80° C.