摘要 |
A liquid crystal compound represented by the formula CH2-CR1-COO-(L)k-E1-E2-E3-E4-R2 wherein R1: a hydrogen atom or a methyl group; R2: a C1-8 alkyl group; k: 0 or 1; L: -(CH2)pO- or -(CH2)q- (wherein each of p and q which are independent of each other, is an integer of from 2 to 8); E1: a 1,4-phenylene group; E2, E3, E4: each independently a 1,4-phenylene group or a trans-1,4-cyclohexylene group and at least one of E2 and E3 is a trans-1,4-cyclohexylene group, provided that the 1,4-phenylene group and trans-1,4-cyclohexylene group in E1 to E4, may be such that a hydrogen atom bonded to a carbon atom in each group may be substituted by a fluorine atom, a chlorine atom or a methyl group. To provide a novel liquid crystal compound for preparing an optical element which can exhibit a proper Rd value depending upon usable wavelength and application and which is excellent in durability against a blue laser beam.
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