Preparation And Performance Of Metal Mesh Conductive Films On Polycarbonate Transparent Parts

The application of polycarbonate(PC)transparent parts in aerospace,military defense and other fields is increasingly expanding.Conductive film prepared on the surface of PC transparent parts can not only provide special functions such as electric heating,and electrostatic dust removal for that applied in complex environment,but also shield the increasingly complex electromagnetic interference(EMI)in the space,ensuring personal safety and information security.Metal mesh transparent conductive film is able to achieve high optical transmittance and high conductivity at the same time,while having the mechanical flexibility as metal film.Thus,metal mesh has a huge development potential.However,the reliable and low-cost manufacturing procedure of metal mesh with high performance is still the main challenge.In this paper,PC has been used as the base to explore the efficient fabrication process of metal mesh conductive film with high performance,and the practical application effect in electric heating and EMI shielding has been deeply studied.The main contents are described as follows:1.A PC-base metal mesh film with low cost,high fabricating efficiency is prepared by combining screen-printing,electroplating and packaging process.Copper and nickel can be selectively deposited in the conductive part of the screen-printed mesh pattern,which has reduced the sheet resistance of the polymer-base metal mesh film to below0.5 Ω/sq,maintaining the optical transmittance above 70% and the average EMI shielding efficiency(EMI SE)reached 24 d B during 8.2～12.4 GHz.Meanwhile,excellent mechanical stability and environmental durability have been obtained by the protection of silicone packaging coating.The electric heater made of PC-base metal mesh film with a sheet resistance of 0.36 Ω/sq can rise to a high temperature of about130 ℃ at the input voltage of 1.2 V,showing the characteristics of outstanding heating power,good heating uniformity,rapid response and high stability.2.A preparation method for PC-base embedded metal mesh film with high resolution,excellent optical transmittance and conductive performance has been developed,by combining soft lithography,scraping and electroplating procedure.The PC-base embedded metal mesh film exhibits a low sheet resistance 0.55 Ω/sq and high optical transmittance of 80%.Moreover,the transmittance can be improved to 88%through the antireflection coating.This method has avoided the restriction between transmittance and conductivity,while the manufacturing cost and time can be greatly economized by employing reusable soft printing mold and patterned silicon substrate prepared by UV lithography.In addition,optimization of the pattern and size leads to the EMI SE(8.2～12.4 GHz)of the PC-base metal mesh film has been improved to 46 d B,maintaining 77% optical transmittance and a low sheet resistance of 0.29 Ω/sq,which exhibits excellent comprehensive property.