Vacuum Aluminum Plating Process

- Jun 11, 2018-

Vacuum aluminum plating refers to the process that the aluminum metal is heated and melted to evaporation, and aluminum atoms condense on the surface of the polymer material to form a very thin aluminum layer under vacuum conditions. Vacuum aluminum plating requires that the substrate surface is smooth, flat and uniform in thickness, the stiffness and friction coefficient are appropriate, the surface tension is more than 38 Dyn/Cm2, the thermal performance is good enough to withstand the heat radiation and condensation heat of the evaporation sources, and the substrate moisture content is less than 0.1%. Commonly used aluminum-plating substrates are polyester (PET), polypropylene (PP), polyamide (PA), polyethylene (PE), polyvinyl chloride (PVC) and others. And process requirements that the degree of vacuum must not be lower than 103 PA in order to avoid brown stripes or uneven thickness of the aluminum layer. Also please control system tension and open the cooling system to avoid tensile deformation of the film due to the heat. Besides, the coiling speed (280 ~ 320m/min), aluminum delivery speed (0.4 ~ 0. 7m/min, 2mm aluminum wire) and evaporation boat heating current need to be precisely controlled to obtain the aluminum layer thickness (100~300A°) required for the product. Coating a certain amount of prime on the film and fully dried in advance before aluminum plating can improve the adhesion of the aluminum layer and the film. Then coating a certain amount of protective resin to prevent oxidation. The aluminum-plated film formed by this process is resistant to friction and is not easily degraded.