Light emitting composition and device

Abstract

A light-emitting composition comprises a polymer and a phosphorescent light-emitting material. The polymer comprises conjugating repeat units of formula (I) and up to 20 mol % of conjugation-blocking repeat units of repeat units of formula (II): Ar1 represents an aryl or heteroaryl group; R1, which may be the same or different in each occurrence, is a substituent; p is 0 or an integer; Ar2 in each occurrence independently represents a substituted or unsubstituted aryl or heteroaryl group; and Sp1 represents an acyclic spacer group that does not provide any conjugation path between the two groups Ar2. Optionally, p is 0, 1, 2, 3 or 4 and each R1 is a non-polar substituent. Each R1 is advantageously selected from C1-30 hydrocarbyl substituents. A light-emitting device comprises an anode, a cathode and a light-emitting layer between the anode and the cathode, the light-emitting layer comprising a light-emitting composition as described.

Dependencies are inferred from the claim text.