Anthracene polymer compound and light emitting device using the same

A polymer compound comprising a constitutional unit of the following formula (1): (wherein, P represents an integer of 1 to 4, Q represents an integer of 0 to 4. R X and R Y represent each independently an alkyl group, alkoxy group, alkylthio group, aryloxy group, arylthio group, arylalkyl group, arylalkoxy group or arylalkylthio group, when there exist a plurality of R X 's, these may be the same or different, and when there exist a plurality of R Y 's, these may be the same or different. Ar 1 represents an unsubstituted or substituted arylene group or an unsubstituted or substituted di-valent heterocyclic group, and Ar 2 represents an unsubstituted or substituted aryl group or an unsubstituted or substituted mono-valent heterocyclic group. A plurality of Ar 1 's and Ar 2 's may each be the same or different.).