添加剂对高双折射液晶紫外稳定性影响

Effect of additive agents on ultraviolet stability of high birefringence liquid crystals

高双折射液晶在液晶显示中具有重要的应用价值,但是由于分子结构中含有不饱和共轭结构,在紫外下不稳定,本文对高双折射液晶紫外不稳定的问题进行了研究。首先在混晶母体A中分别加入几种不同结构的添加剂三苯氧膦、丙基双环己基甲醛、丙基苯(3,5-2F)溴苯、UV-P,搅拌使其溶解均匀,将液晶灌入TN-7.0-R测试盒,在紫外下曝光后测试混晶的各项参数。实验结果表明:UV-P明显提高了高双折射液晶的抗紫外性能,因为UV-P的紫外吸收光谱带与高双折射液晶母体A的紫外吸收光谱带最接近。

The high birefringence liquid crystals have important applications in LCD,but they are in-stable under UV exposure due to the conj ugated unsaturated structures.The ultraviolet stability of high birefringence liquid crystals was studied in this paper.First,several different additives were add-ed to the liquid crystal mixture A,such as triphenylphosphine oxide,4’-propylbi（cyclohexane）-4-formaldehyde,4-propyl-4’-cyclopentyl-3,5-difluorobiphenyl and UV-P.The liquid crystal mixtures were poured into TN-7.0-R test cells after stirred uniformly,then the test cells were exposed to ultra-violet,finally the liquid crystal parameters were tested.The results show that the UV stability of liq-uid crystal A can be significantly improved by UV-P,because the UV absorption of UV-P is most sim-ilar with liquid crystal A.