Study On The Preparation Equipment And Forming Mechanism Of Diffusion Film Based On Photocuring Micro-imprint

The diffusion film is an optical film that realizes uniform distribution of emitted light,which utilizes the combined effects of reflection,refraction and scattering when light passes through different materials.It is widely used in lighting,display and other fields.This topic is different from traditional extrusion,hot pressing and other processing methods.In this paper,a new type of photocuring micro-imprinting method is used to prepare the diffusion film.Different types of diffusion membranes were prepared by self-designed and manufactured photo-curable micro-imprinting equipment and mold,and the effects of material formulation and molding process on the performance of the diffusion membrane were explored.The main work is as follows:1.Designed and processed a set of photo-curing micro-imprinting experimental equipment,which mainly includes three parts:imprinting unit,ultraviolet irradiation system and workbench.At the same time,optical simulation of the micro-structured diffusion film,selected microstructure specifications.The lithography reprint method was used to make the PDMS mold and the related process was explored.2.A micro-structured diffusion film was prepared.The effects of imprint pressure and irradiation time on the micro-structural replication of the diffusion film surface,the influence of monomer type and content on the quality of the diffusion film were studied.The causes of warpage deformation of the diffusion film were analyzed from three aspects of irradiation intensity,holding time and oligomer content.Explore the best formulation for this experiment and test the properties of the diffusion film:the surface micro-structure height and width are all more than 90%,the coating adhesion is 4B,the visible light transmittance is 89%,and the maximum haze is 60.32%.3.The particle-type diffusion film was prepared and the effect of irradiation time on the apparent quality of the diffusion film was studied.The effects of particle size,mass percentage and ratio of different functional group oligomers on the optical properties of the diffusion film were investigated.The effect of the percentage of light diffusing agent on the tensile strength of the diffusion film was analyzed.The experimental results show that the apparent morphology of the diffusion film is good when the irradiation time is 6s;When the particle size of the light diffusing agent is 5 ?m and the mass percentage is 40%,the integrated optical performance of the diffusing film is optimal;An increase in the proportion of the hexafunctional oligomer causes a decrease in the light transmittance of the diffusion film;an increase in the content of the light diffusing agent causes a decrease in the tensile strength of the diffusion film.4.Based on the above work,a composite diffusion film was prepared.The optimum light diffusing agent content of the film was found to be 20%,and the optimum imprinting pressure was 6N.At this time,the diffusion film has good optical properties:a light transmittance of 74.45%and a haze of 92.21%.At the same time,the product was tested:In the epigenetic diagram,the microstructure is well formed,the light diffusing agent is evenly distributed in the cross-sectional view,and the uniformity of the diffused film illumination is 90.6%,and the direct diffusion effect is good.