Influence Of TFT-LCD Liquid Crystal Mixture On The Image Sticking

In recent years, various display technologies have been developed rapidly, where Liquid Crystal Display (LCD) became the most important one because of wide application in IT and electronic industry. Accompanied with the market ratio of LCD becoming larger and larger, higher quality and performance is expected, such as response time, contrast ratio, wide view angle and low power consumption, and so on. Thus, some defects which can be ignored previously become non-acceptable in market now, and"Image Remain", that is"Image Sticking"is one of them. Recently, the"Image Sticking", as the important problem that many factories want to resolving, is discussed in many literatures.In this paper, the manufacturing process of TFT-LCD, the evaluation and the sorting method of"Image Sticking"are introduced in brief. The mechanism of"Image Sticking"is also discussed. The composition of 5 kinds of TFT-LCD used Liquid Crystal mixture from Germany and Japan makers is analyzed. We measured the single molecules and the compound ratio of five compositions respectively. Through evaluating the area image sticking and line image sticking level of TFT-LCD using the 5 kinds of LC mixture, the relationship between LC mixture composition and line image sticking is analyzed. We put the relationship between the composition of liquid crystal and"line image sticking"as the key point. We found if the ?εis larger, the polarity of LC mixture is stronger, the stability will be worse and the line image sticking will be worse; the stability and line image sticking level of the LC mixture containing butanylbenzene series singles is worse.PI layer is one of the key factors that have much effect on the"Image Sticking". At the same time, by checking pretilt angle, surface tension, ion chromatograph, and Tof-SIMS of panels with bad image sticking performance, it's found that higher concentration of organic acids and Cl- ion detected in LC and higher Na+ ion concentration remained in PI will result in more serious line image sticking, which will help to improve the image sticking performance of LCD by selecting appropriate PI materials.