微流控法制备可用于电泳显示微胶囊的微液珠研究

Microfluidic Fabrication of Monodisperse Microdroplets for Electrophoretic Display Applications

基于微流控技术,提出一种制备电泳显示液微胶囊的新方法,解决了传统电泳微胶囊制备方法中颗粒粒径不均匀、影响显示器件的显示性能及其驱动波形设计等问题.使用2种玻璃汇聚流通道(小型和大型),外相溶液为1.5%明胶阿拉伯胶混合溶液,内相为四氯乙烯溶液.当小型通道和大型通道外相溶液流速与内相溶液体积流速比分别为2∶1和10∶6时,可得到液滴平均直径分别为47μm和315μm的均匀的微液珠.同时,通过调节内外相流速可以精确控制微胶囊粒径大小.与传统机械搅拌法制备的微液珠(52±18.81μm)相比,微流控法制备的微液珠(45±0.28μm)粒径分布得到了很大改善.该方法为电泳显示器显示效果的改善提供了可行方法.

A novel method of creating monodisperse microdroplets for electrophoretic display microcapsules application is introduced. The microeapsules fabricated by common agitation are lack of uniformity, which result in difficulty in driving waveform design. In this report, the narrow distributed microdroplets of EPD materials using two types of microchannel with the outer phase of 1.5 % gelatin and Arabic gum solution and the inner phase of tetraehloroethylene are fabricated. Controlling the flow rate ratio of the inner to outer phase at 2：1 （small channel） and 10：6 （big channel）, monodisperse microdroplets with diameter of 47 μm and 315 μm are obtained, respectively. At the same time, the size of the microdroplet could be precisely controlled by the fluidic flow rates. The size distribution of the microdroplets fabricated by microfluidic channels was （45 ± 0.28 ） μm which was highly improved comparing to the droplets created by agitation with the size of （52 ± 18.81 ） μm. This implies that the microfluidics is a reliable technology which would be a feasible way to improve the quality and performance of the electrophoretic displays.