【作者】 乔淑楠；

【导师】 李路海；

【作者基本信息】 北京印刷学院 ， 材料物理与化学， 2008， 硕士

【摘要】 电子纸,是具有普通纸质印刷物显示效果的超薄、柔软的电子显示器件,具有高反射率、宽视角、柔软便携、双稳态显示、耗电量低等特点。近年来,电子纸受到了广泛关注。电泳显示电子纸技术,是多种电子纸技术中发展最成熟,最接近产业化的技术之一。传统的电泳显示电子纸器件是基于分散体系中的带电颜料颗粒在电场下发生电泳移动完成显示的。文献记载的电泳显示电子纸原理器件所采用的电泳显示颗粒集中在无机颜料颗粒如二氧化钛、二氧化硅、有机颜料,如PY14,PY12这两大类上。但是颜料电泳的最大缺点就是体系稳定性差。电泳显示过程中,由于比重大,颜料颗粒很容易絮凝,沉降破坏显示。能否找到一种新的电泳显色材料代替颜料是设计本课题的出发点,在此基础上研究染料电泳体系的电泳原理是本文的最终目的。本文通过实验测试了几类染料电泳电子墨水的组成与性能关系,通过金相显微镜拍摄的照片详细地描述了染料电泳过程,密度计记录了染料电泳前后的密度变化,集中测试了金属络合染料类和酸性染料类电子墨水的电化学性能,系统研究了染料在溶剂中的存在状态。此外,对染料电泳响应时间的影响因素,以及染料体系吸光度随时间的变化进行了系统的研究。本文的研究证实了染料电泳显示,找到了几种电泳性能较好的染料电泳体系,通过测试证明了染料在溶剂中并不是以单个分子存在,而是以分子的聚集态形式存在。进而推测电泳显示电泳液中染料带电的原理。此外,确定了金属络合红Red04和酸性黑1染料在电泳过程中伴随着电化学反应的发生,生成了氧化偶氮苯。并且测试得到了四种染料电泳的响应时间,分析染料电泳速度较慢的原因。认为目前染料在电子纸中的应用具有一定的局限性。更多还原

【Abstract】 Electronic paper technology has received a great deal of attention in recent years. Electronic paper is a paper—like display monitor which has many properties such as high reflection, wide visual angle, portability, flexibility and bistable. Electrophoresis image displays (EPID) is the most likely candidate in search for a display which has these properties.Traditional EPIDs are thin, flexible reflective displays based on the movement of electrical charged pigment particles which are dispersed in a colored dielectric medium. Most of the reported prototype electronic papers are based on the electrophoresis of charged particles in colloidal suspension, which take the inorganic pigment titanium dioxide (TiO2) or silicon dioxide (SiO2) as particles. The dielectric medium such as tetrachloroethylene, isopar, xylene, are of high specific gravity to compatible with pigment particles. However, the pigment electrophoresis ink has a problem with suspension stability such as agglomeration, lateral migration and sedimentation because of the high density of pigment. Other materials which can substitute pigments as colored particles and the solvents which can disperse the colored particles well will be introduced later in this paper. Indeed, there are many papers referring to organic and inorganic pigment particle electrophoresis colloid, while less report is concerned about the electrophoresis of dye. In order to prepare a novel electronic ink, this study has been focused on the principle of electrophoresis of dye in different solvent or surfactant, and the relationship between the composition and electrophoresis properties of the electronic ink of dye.Dozens of dye have been tested in this paper including dispersed dyes, acid dyes, solvent dyes, metal complex dye and etc. To compatible with dye, several kinds of solvents and charge control agents also have been tested including pyridine, ethanol, xylene, Tetrachlorethylene, diethylamine, aniline, PIBI. Dyes were dissolved or dispersed in the solvents with certain surfactant and the electrophoresis performance of the solvent was observed in electrophoresis display prototype which was composed by 2 pieces of parallel ITO glass.The process of dye electrophoresis was described by photos of Metallurgical Microscopy; the density change of dye system before and after electrophoresis was recorded by X-Rite, in these ways we generally know the phenomenon of dye electrophoresis.The electrochemistry reaction of the dye, solvent and electrode was determined by electrochemistry station. It can be found that the system consisting of conductive medium is instable in electrophoresis. Electrode, electrophoresis media and dyes would be suffered electrochemical damage under the supplied voltage. Most of the dye in polarity medium would decompose during electrophoresis if the applied voltage is higher than certain value.And we also study the state of dye in the solvent. It was confirmed that the dye was not existed individually in the solvent, but was gathered together. Because dye particles of electronic ink was smaller than pigment of Electronic ink, so it was solved that pigment in the solvent were easily gathered. And luckily it was showed that it was clear and easily distinguishable before and after the dye system electrophoresis.Additionally, we tested the dye electrophoresis response time through UV-Vis spectrophotometer, and studied the factors of influencing dye electrophoresis response time, including the voltage, the concentration of dye system and structure of dye. And the UV-visible absorption change of a fixed point with time was also systematically studied.It was insufficient that the best electrophoresis performance is the dye solution of weak polar system in the present, when the voltage greater than a certain value, the system will happen electrochemical reaction, leading to dye decomposition.更多还原