CF_(4)-GMET和G-PT处理对AR+AF涂层耐磨性能的影响

Effects of CF_(4)-GMET and G-PT Treatment on Wear Resistance of AR+AF Coating

目的在兼顾涂层抗反射性和疏水性的前提下,通过强化抗反射(AR)多层复合膜系与抗指纹(AF)涂层之间的黏附力,提升复合涂层的机械耐久性能。方法采用磁控溅射法在玻璃衬底上沉积AR多层复合膜系,首创性地采用CF_(4)气体微刻蚀(CF_(4)-Gas Micro-etching Treatment,CF_(4)-GMET)与石墨等离子体(Graphite Plasma Treatment,G-PT),依次对AR膜系表面进行处理后,将AF试剂蒸镀附于AR层表面并冷却,即可得到具有超强耐磨性的AF/CF_(4)-GMET&G-PT SiO_(2)/AR抗反射疏水涂层。结果CF_(4)-GMET对AR表层SiO_(2)处理后,其表面“柱状尖峰”消失,得到低粗糙度针状表面,并增大了SiO_(2)与AF涂层的接触比表面积。G-PT处理大幅提高了表层SiO_(2)亲水性,从而使得SiO_(2)表面黏附功增大。经2道工艺处理后,SiO_(2)表面粗糙度降低,黏附功先降后升为最大值,蒸镀AF疏水涂层后界面结合最为稳定,耐磨性能显著增强。在负载为1000 g的钢丝绒摩擦10000次后,抗反射疏水涂层的水接触角(WCA)从117.7°下降至113.6°,磨损率仅为3.4%,耐磨性能极佳。结论对AR膜系表层SiO_(2)进行CF_(4)-GMET和G-PT处理,能显著提高抗反射疏水涂层的耐磨性能,而对光学透过率基本无影响。

Glass cover plate is an indispensable component of consumer display electronic products,these products will inevitably be stained with fingerprints,grease and other pollutants during use.However,the anti-fouling performance of the existing glass cover plate will gradually fail with the increase of the number of wear during use.Therefore,it is an urgent demand for the market to develop a type of optical hydrophobic glass with excellent wear resistance.When taking account of anti-reflectivity and hydrophobicity at one and the same time,the interfacial bond between antireflective(AR)multi-layer composite film system and anti-fingerprint(AF)coating was strengthened to enhance the mechanical durability of the composite coating.CF_(4)gas micro-etching treatment(CF_(4)-GMET)and graphite plasma treatment(G-PT)were first combined to treat the surface of the AR multi-layer composite film deposited on the glass substrate by magnetron sputtering in proper sequence,before AF reagent evaporated on the surface of the AR coating is cooled to obtain an AF/CF_(4)-GMET&G-PT SiO_(2)/AR anti-reflective hydrophobic coating with super wear resistance.In order to study the wettability and surface morphology of SiO_(2)on the AR surface,a water contact angle tester was used to measure the water contact angle and adhesion of samples.The surface morphology and roughness of SiO_(2)films were characterized by atomic force microscopy.Wear resistance and optical transmittance of samples were measured by friction life testing machine and UV-visible near infrared spectrophotometer,and the wear resistance and optical properties of different samples were compared.The influences of interface adhesion and surface roughness on wear resistance were compared by analyzing the correlation among adhesion,surface morphology and wear resistance test results of samples.After imposed on the AR surface by CF_(4)-GMET,"cylindrical spike"was removed to obtain a low roughness needle surface,to increase the contact ratio surface area between SiO_(2)and AF coatings.In this process,the hydrophobicity of samples increased,while the adhesion decreased.The adhesion of the SiO_(2)surface was greatly improved by G-PT to increase the surface hydrophilicity.After two treatments above,the roughness of the SiO_(2)surface decreased meanwhile the adhesion decreased at first and then rose to the maximum value,which resulted in the significantly enhancement of wear resistance of AF coating evaporated.After 10000 frictions of steel velvet with the load of 1000 g,the water contact angle(WCA)value of the anti-reflective hydrophobic coating decreased from 117.7°to 113.6°,with a wear rate of only 3.4%and excellent wear resistance.The results showed that both of the wear resistance and hydrophilicity were enhanced through the treatments of CF_(4)-GMET and G-PT on the surface of the AR composite film system;however,the treatments hardly no impact on optical transmittance.After the micro-etching of SiO_(2)by CF_(4)-GMET treatment,the surface roughness was reduced and the single-scale roughness structure was also transformed into a multi-scale roughness structure.The appearance of multi-scale roughness structure increased the contact area between the SiO_(2)layer and the AF layer,which was beneficial to the adhesion and blending of liquid AF reagent during evaporation.G-PT treatment co increases the adhesion of the SiO_(2)surface and improve the interface strength between the SiO_(2)layer and the AF layer.This method is easy used to improve the wear resistance of the anti-reflective hydrophobic coating,and it has been widely applications in automotive central control platforms,electronic display covers,and smart wearable products,etc.