液晶与显示, 2016, 31 (1): 40, 网络出版: 2016-03-22
苯并菲类盘状液晶的合成及应用
Synthesis and application of triphenylene discotic liquid crystals
苯并菲 盘状液晶 光学补偿膜 负光学各向异性。 triphenylene discotic liquid crystals optical compensation film negative optical anisotropy
摘要
为了改善扭曲向列相(TN)型液晶显示的视角差的现象, 合成了一种具有苯并菲结构的盘状液晶单体, 并以该盘状液晶单体为材料制备了简易的光学补偿膜片。以4-氯丁醇乙酸酯、对羟基苯甲酸甲酯和邻苯二甲醚为原料, 通过七步反应以较高收率合成了一种具有苯并菲结构的盘状液晶单体。通过核磁共振(NMR)和元素分析(EA)确认了分子结构的正确性; 利用偏光显微镜(POM)、预倾角测试仪和示差扫描量热仪(DSC)等对其液晶参数进行测定, 并以该苯并菲单体为材料通过基板处理、摩擦配向、涂布等过程制备了光学补偿膜片。实验表明, 该苯并菲盘状液晶单体具有负的光学各向异性值(Δn=-0.060 8)、较宽的向列相温宽(54.6~166.4 ℃), 所制得的简易光学补偿膜片具有一定的补偿效果(Rth=137 nm)。该苯并菲类盘状液晶化合物可以作为光学补偿膜材料使用, 且制备方法简单, 原料易得, 收率较高, 易于实现大规模生产。
Abstract
In order to improve the view angle of twisted nematic liquid crystal display (TN LCD), we synthesized a triphenylene discotic liquid crystals and prepared simple optical compensation film by using this material. This triphenylene discotic compound was synthesized from 4-chlorobutyl acetate, methyl 4-hydroxybenzoate and 1,2-dimethoxybenzene by seven steps in high yield. The construction was confirmed by nuclear magnetic resonance (NMR) and elemental analysis (EA). We also measured the parameters and the performances of this compound by polarizing optical microscope (POM), pretilt angle tester and differential scanning calorimetry (DSC). Simple optical compensation film was prepared by several steps including substrate surface treatment, rubbing-alignment, coating and so on. This triphenylene discotic compound has negative optical anisotropy (Δn=-0.060 8), wide nematic phase range (54.6~166.4 ℃), the optical compensation film has a certain compensative effect (Rth=137 nm). This triphenylene discotic compound can be used in optical compensation film of the TN LCD. The preparation method is of simple operation and low cost, which can also realize industrialization easily.
隋岩, 郭剑, 李正强, 华瑞茂. 苯并菲类盘状液晶的合成及应用[J]. 液晶与显示, 2016, 31(1): 40. SUI Yan, GUO Jian, LI Zheng-qiang, HUA Rui-mao. Synthesis and application of triphenylene discotic liquid crystals[J]. Chinese Journal of Liquid Crystals and Displays, 2016, 31(1): 40.