Briefly describe the diffusion film of PET film:
The diffusion film mainly spreads the astigmatism particles on both sides of the transparent PET film substrate (mainly the polyester base film) to diffuse the light, and can diffuse the line source into a surface light source. The important indicators of the diffusion film are total light transmittance and haze. The diffusion sheet is further divided into an upper diffusion sheet and a lower diffusion sheet. The haze of the upper diffusion sheet is generally ≤70%, and the haze of the lower diffusion sheet is generally ≥80%.
At present, the global manufacturer of diffusion membrane master rolls is mainly in Japan, mainly concentrated in Japan, Huihe, Zhiji, etc. Korean manufacturers mainly rely on SKC, SBK and MNtech, mainly supplying Korean customers; Taiwanese manufacturers have previously processed and processed Mainly, Changxing Chemical and Xuan Mao Technology have entered the field of diffusion film manufacturing in recent years.
The core barrier of the diffusion film is precision coating. When the diffusion film is applied, there is a slight uneven thickness locally, and the defects of the film on the film can be seen immediately. The thickness error of the diffusion film is generally ±5%, and after subtracting 1% of the substrate thickness error, 4% remains. The thickness of the diffusion film coating is usually 10~20um, which shows that the precision of the coating machine is extremely high.
Since the diffusion film is among the three kinds of optical films, the technical barrier is relatively low, and it is also the most promising field in China.
