有机纳米颜料对彩膜滤光片的对比度影响

彩膜滤光片主要采用有机纳米颜料体系为主,是因为颜料具有良好的热稳定性、耐光性和耐化学性,可以满足LCD的工艺制程。而颜料的颗粒属性,是影响彩膜滤光片穿透率和对比度的主要因素。在三原色中,绿色的亮度最高,对对比度的影响也最大。因此,本文主要研究一种具有广色域的绿色滤光片,其由3种有机纳米颜料组成颜料绿58(G58)、颜料黄138(Y138)、颜料黄185(Y185)。其中Y185的加入是基于其高的着色率,可以有效降低滤光片的膜厚;然而,即使少量Y185的加入(5%颜料比例)也会使得整体的对比度呈现明显下降(20%)。为解析Y185造成对比度偏低的原因,本文主要采用同步对比来分析两种颜料的粒径、n值(折射率)、晶型及形貌和荧光特性之间的差异。研究结果表明,Y185造成对比度偏低的主要原因是在成膜或者干燥过程中有机纳米颜料粒子的团聚。本文通过系统地研究有机纳米颜料造成对比度偏低的原因,为提升有机纳米颜料的对比度和制备高对比度的彩膜滤光片提供了理论依据和设计方向。

Effect of organic nano-pigments on contrast ratio of color filters

The pigments have advantages on thermal stability,light resistance and chemical resistance,so they are wildly applied to manufacturing color filters.However,the color filters manufactured with pigments have introduced spectral drawbacks such as decreased transmittance of light and decreased contrast ratio(CR)both caused by organic nano-pigments.Among the three primary colors,green one has the highest brightness and the greatest effect on CR.In this study,our focus is on a green color filter with wide color gamut,which mainly contains three pigments,such as pigment green 58(G58),pigment yellow 138(Y138),and pigment yellow 185(Y185).The Y185 with high tinctorial strength has been introduced to effectively reduce the color filter thickness,but the CR is decreased.In this paper,the effect of scattering and fluorescence on CR of Y138 and Y185 are analyzed.The size,n(refractive index),crystal structure,morphology and fluorescence properties of these two kinds of pigments have been compared.The results show that the aggregation of Y185 organic nano-pigments in CF manufacturing process is the main reason,which leads to the lowered CR.By systematically investigating the effects of the organic nano-pigments on CR,this paper provides a theoretical basis and guidance for realizing the CFs with high CRs by designing organic nano-pigments.