Research On The Construction Of Bacteriostatic, Absorbing UV And Self-healing Coating On The Surface Of Touch Screen

With the rapid development of electronic technology,touch screens are widely used in various electronic devices.However,its convenience in production and life has also brought hidden dangers to people's health:Firstly,the touch screen surface is difficult to clean and disinfect,greatly increasing the probability of pathogen transmission;Secondly,the surface of the touch screen reflects ultraviolet light,which will bring various health hazards to the user,and even cause skin cancer;Thirdly,the touch screen on the public equipment is susceptible to mechanical damage,which not only reduces the clarity of the surface of the panel,but also increases the adhesion and proliferation of bacteria in the scratched portion to form a biofilm.In view of this,this paper designs coatings with antibacterial,selective absorption of ultraviolet light and self-healing function on the surface of the touch screen to protect the user's health while preventing the loss of protective function caused by the scratch of the coatings.The research content is as follows:1.Preparation of polymer composite microgels based on polyquaternium-10?PQ?and sodium alginate?SA?,and then constructing PQ/SA microgel coatings on the surface of touch screen by pouring self-assembly method.Further cross-linking and hydrolyzing peroxotitanic acid?PTA?in the coatings,a large amount of uniformly dispersed ultraviolet light absorbers,nanometer titanium dioxide?TiO₂?,can be formed in situ in the coatings to obtain PQ-TiO₂-SA coatings.Coordination bonds and ionic bonds can be formed between TiO₂ and the internal polymer of the coatings.This strategy can solve the problem of poor uniformity of inorganic nanoparticle coatings by traditional self-assembly methods,and can also deal with the problem of poor water solubility of self-assembled polymer coatings.At the same time,the polymer chain inside the coatings retain certain fluidity.The effects of PQ and SA feeding ratio on the water resistance,ultraviolet light absorbing ability,self-healing ability,anti-aging ability and antibacterial property of the coatings were studied in detail to optimize the coatings preparation conditions.The results show that when the mass ratio of PQ to SA is 2:1,the PQ₂-TiO₂-SA₁ coating can effectively absorb UV-B and transmit visible light.It is stable in aqueous solution and can repair scratches with 25?m wide.2.In order to further enhance the antibacterial activity of the coatings and prevent the resistance of the bacteria,the two active ingredients of resveratrol and quercetin are selected as antibacterial agents to prepare composite coatings.Firstly,resveratrol borate?ReB?and quercetin borate?QuB?hydrosol were prepared by exchanging solvent and borated acid esterification reaction to solve the problem of poor water solubility.The size,charge properties,and microscopic morphology were analyzed for their formation mechanism.Then,the drug nanoparticles are loaded into the PQ-TiO₂-SA coating by the infiltration method to obtain a composite functional coatings for inhibiting bacteria and absorbing ultraviolet rays.The system characterization and performance studies of the composite coatings show that the adsorption amount of the nanoparticle is greater than that of the direct adsorption bacteriostatic molecules,and the bacteriostatic agent is more likely to be slowly released in the physiological environment.The drug-loaded coatings have more excellent antibacterial activity than PQ-TiO₂-SA,and the inhibition rate of Gram-positive bacteria?S.aureus?and Gram-negative bacteria?E.coli?exceed 99%and 95%.The results of the damage repair experiment showed that the introduction of the nanoparticle did not affect the self-healing function of the coatings.The physical scratch with a surface width of about 25?m could be repaired automatically within 30 s.The pencil hardness test showed that the coatings were resistant to 5H pencil,and the adhesion level between the coatings and the substrate is 5A.The results of spectroscopy experiments show that the coatings not only have a transmittance of UVB close to zero,but also have a good absorption effect on UVA and blue light which induce skin melanin production and damage visual acuity.More importantly,they do not affect the transmission of visible light.