Patent ID: 8304037

Claim:
A compound represented by formula (1): wherein R 1 and R 2 are each independently alkyl having 1 to 10 carbons, and in the alkyl, arbitrary —CH 2 — may be replaced by —O—, —S—, —CO—, —CH═CH— or —C≡C—, and in these groups, arbitrary hydrogen may be replaced by halogen or —C≡N; A 1 and A 2 are each independently 1,4-cyclohexylene, 1,4-cyclohexenylene or 1,4-phenylene, and in these rings, arbitrary —CH 2 — may be replaced by —O—, arbitrary —CH═ may be replaced by —N═, and arbitrary hydrogen may be replaced by fluorine, chlorine or bromine; Z 1 and Z 2 are each independently a single bond, —(CH 2 ) 2 —, —(CF 2 ) 2 —, —COO—, —OCO—, —OCH 2 —, —CH 2 O—, —CH═CH—, —C≡C—, —(CH 2 ) 4 —, —O(CH 2 ) 3 — or —(CH 2 ) 3 O—; X is fluorine or chlorine; and p and q are each independently 0 or 1.