The present invention aims at providing a retardation element which has excellent heat resistance, is small in the changes in the retardation value in an atmosphere of high temperatures, and is capable of maintaining stable optical performance.
The present invention pertains to a retardation element containing a liquid crystalline compound, and at least one compound selected from the group consisting of a compound represented by the following formula (1), a compound represented by the following formula (2) and a compound represented by the following formula (3). In the formula (1), n represents an integer of 3 to 10 and R2 represents a -CH2-CH2- group, a -CH2-CH(CH3) - group or a - CH2-CH2-CH2- group. In the formula (2), R3 represents a - (CH2)p- group or a phenylene group and p represents an integer of 4 to 8. In the formula (3), R4 represents a substituted phenylene group. In the formulas (1) to (3), R1-1, R1-2 and R1-3 each represent an alkyl group having a branched structure having 5 or more carbon atoms and R1-1, R1-2 and R1-3 may be the same or different.
本发明旨在提供一种延缓元件,它具有优异的耐热性,在高温环境中延缓值变化小,并能保持稳定的光学性能。
本发明涉及一种含有
液晶化合物和至少一种从下式(1)、下式(2)和下式(3)所代表的化合物中选出的化合物的缓凝元件。在式(1)中,n 代表 3 至 10 的整数,R2 代表-
CH2- -基团、- -CH(
CH3)-基团或- - - -基团。在式 (2) 中,R3 代表-( )p-基团或亚
苯基,p 代表 4 至 8 的整数。在式 (3) 中,R4 代表取代的亚
苯基。在式(1)至式(3)中,R1-1、R1-2 和 R1-3 分别代表具有 5 个或更多
碳原子的支链结构的烷基,R1-1、R1-2 和 R1-3 可以相同或不同。