Patent ID: 7101595

Claim:
A compound represented by Formula (1): wherein R 1 and R 2 are independently hydrogen or alkyl having a carbon number of 1 to 5; R 3 and R 4 are independently hydrogen, fluorine, chlorine or alkyl having a carbon number of 1 to 20; optional —CH 2 — in the above alkyl may be substituted with —O—, —S—, —COO—, —OCO—, —CO—, —CH═CH— or —C≡C—, and optional hydrogen in the above alkyl may be substituted with halogen; Y 1 and Y 2 are independently alkylene having a carbon number of 1 to 15, and optional —CH 2 — in the above alkylene may be substituted with —O—; A 1 and A 2 are independently 1,4-cyclohexylene, 1,4-cyclohexylene in which at least one hydrogen is substituted with fluorine, 1,4-cyclohexenylene, 1,4-phenylene, 1,4-phenylene in which at least one hydrogen is substituted with halogen, methyl or trifluoromethyl, pyridine-2,5-diyl, pyridazine-3,6-diyl, pyrimidine-2,5-diyl, naphthalene-2,6-diyl, tetrahydronaphthalene-2,6-diyl or 1,3-dioxane-2,5-diyl; X 1 and X 2 are independently a single bond, —O—, —S—, —COO— or —OCO—; X 3 and X 4 are independently —COO—, —OCO—, —CH 2 CH 2 — or —C ≡C—; and m and n are independently 1 or 0.