In the material composition of the LCD backlight, the diffusion film is almost one of the essential materials. Diffusion films are categorized according to the method of manufacture. There are two kinds of coating methods: non-coating and coating. Among them, the coated diffusion film has a high light transmittance, a large haze adjustment range, and a good appearance quality, and is a preferred type of diffusion film for high-end backlight products. Diffusion film according to the form points, there are two kinds of roll and sheet material. This article only describes the production technology of the coating type diffusion membrane (abbreviated as diffusion membrane).
According to the survey, the industry's understanding of the diffusion film is divided into three levels: the user is the first level, the cutter is the second level, and the spreader is the third level. Since most people in the industry know more about the first two levels, this article will not introduce them. Diffusion film coating has the characteristics of high technical content, large capital investment, high production efficiency, and considerable economic benefits. Therefore, some people in the country always want to get involved and dare not easily get involved. This article will introduce this third level in particular, hoping to have some reference value for this person who wants to get involved. The third level can also be called mastering. Currently, the world's main manufacturers of diffusion membranes are: KEIWA, TSUJIDEN, and KIMOTO in Japan; SKC, shinwha, and Seahan in Korea; and Changxing Chemical in Taiwan, China. Xuan Mao Technology, Hua Hong New Technology and Sinrow, etc.; China is still in its infancy, and there is no large batch supplier.
In the past two years, as the forerunner of the domestic industry, the author experienced the entire process from the exploration of diffusion membranes to mass production. Today, all technical indicators have reached the level of similar diffusion membrane products in Japan. Achieve the initial goal of high quality and low price. Diffusion film production technology involves diaphragm design, equipment selection, materials and formulations, coating process, quality control and other work. Knowledge areas include: Applied Optics, Organic Chemistry, Precision Machinery, Decontamination Engineering and Backlighting Technologies, Coating Technology, etc.