Research On Anti-adhesion Process Of Quartz Substrate For Constrain-surface Curing Chamber In Mask Projection Stereo-Lithography

The mask projection stereo-lithography systems are applying a photo-mask based on the specific layer contour to select the light exposure onto the predefined position,in which,the parts building efficiency is improved significantly since a whole thin layer of a 2D shape is formed consuming a single exposure time.The critical problem in the mask projection stereo-lithography process is that during parts forming process,the resin is cured and separated from quartz substrate repeatedly and the peeling failure occurs during the stripping process,which leads to the failure of the parts building.Curing resin layer separation process from the resin tank substrate surface is essentially to overcome the adhesion force between the interface between the cured layer and the substrate through an external force.Considering the influence of mechanical properties of resin material and deformation on the forming precision,the external force should not be too large.Therefore,the basic idea to solve the above problems is to reduce the adhesion force between the solidified resin layer and the substrate.At present,the resin tank needs to be replaced frequently due to the adhesion of cured resin,which has become the main problem restricting the further promotion of such 3D printing equipment.To reduce the interfacial adhesion between the cured layer and the substrate and improve service life of the anti-adhesion functional film,in this paper,the functional film with low surface energy formation method through nanostructures fabrication on the surface of substrate bulk is proposed.The functional film fabrication process,anti-adhesion and optical transmission of the functional film have been studied.The main work and conclusions are as follows:The anti-adhesion functional film has been fabricated through study on the synthesis of nano-spheres,the single-layer nano-sphere closed-packing and pattern transfer etching.The influence of various factors on properties of nano silicon dioxide pellets has been studied systematically and the process parameters for synthesis of nano particles with required diameter size and diameter uniformity have been identified.The nano silicon dioxide pellets function as subsequent etching mask and hence the single-layer nanosphere spreading on the substrate surface is required.Then the process for monolayer silica nanospheres close-packing has been studied and the highly uniform close-packed monolayer films have been demonstrated.The influence of etching process parameters on the geometric size,shape and uniformity of etched nanostructures and the uniform nano spheres arrays have been demonstrated.The test and characterization of surface nanostructures with various diameters and various morphologies have been conducted.The results show that nanostructures influence the interfacial contact mode and proper nanostructure morphology facilitates interface adhesion force reduction.In addition,the structure with sub-wavelength feature size facilitates optical transmission rate.The interface adhesion force of the cured resin on fabricated surface has been measured preliminarily.The parts building test on the fabricated function film surface is conducted and the anti-adhesion effect of the functional film is evaluated preliminarily.