TFT-LCD工艺中角落白Mura的成因机理研究与改善

在新产品导入过程中会突发各种Mura类不良。本文为解决TV机种导入中出现的一种原因未知的角落白Mura,首先进行了大量的排查和推理,初步判定异常来源于成盒工艺(Cell)段,利用气相色谱(GC)、高效液相色谱(HPLC)设备测试并对比了角落白Mura区域与正常区域的液晶纯度、液晶组份和框胶溶出的差异,最后探讨了其形成的机理。结果表明角落白Mura区域液晶组份发生较大变动,液晶组份挥发是角落白Mura产生的主因。通过优化贴合时的真空抽气时间、真空保持时间、液晶滴下点数、液晶与边框胶距离等一系列的改善措施,使产品的角落白Mura发生率从16.59%降到了0.001%以下管控范围。实验有效解决了角落白Mura异常并为今后类似Mura类不良的对策提供了思路,同时提升了公司的效益和竞争力。

Research and improvement of corner white Mura in TFT-LCD

At present, a variety of sudden Mura phenomena always appear in the process of introducing new products. In this paper, in order to solve the problem of a new unknown corner white Mura which happened in TV product process, a lot of investigation and reasoning work are carried out, firstly. Preliminary, we estimate the Mura is derived from the Cell segment. We measure the liquid crystal purity, the liquid crystal component and the sealant dissolubility difference of the Mura region by using gas chromatography (GC) and high performance liquid chromatography (HPLC). Comparing with the normal region, the formation mechanism is discussed. The results show that the liquid crystal components change a lot in the corner white Mura area and the main cause of corner white Mura is the volatilization of liquid crystal components. By taking a series of improvement measures such as optimizing vacuum extraction time, vacuum holding time, liquid crystal drop points, the distance between liquid crystal and sealant and so on, the rate of corner white Mura is decreased from 16.59% to below 0.001%. Our experiments effectively solve the problem of corner white Mura abnormity and provide some methods to solving similar Mura's countermeasures in the future. At the same time, our company's efficiency and competitiveness are promoted.