| abstract |
In structural formula (1), X1 and X2 are each independently a photopolymerizable functional group, a structural site having a photopolymerizable functional group, or a hydrogen atom, at least one of X1 and X2 is a photopolymerizable functional group or a structural site having a photopolymerizable functional group, R1 and R2 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a bromine atom, or a chlorine atom, and at least one of R1 and R2 is a hydrogen atom. |