Design And Fabrication Of Colorful Decorative Coatings On Plastic Substrates

Decorative coatings have found wide application in practice. Usually these coatings are designed with filter method which is very complicated, and the structures of designed stacks are complex and prove hard for production. This paper mainly focuses on a new design method for decorative coatings deposited on plastic substrate, and solves some key technical problems encountered in the fabrication of the coatings. Based on the theory of thin film interference, the relationship between the reflective color and film thickness is deduced and corresponding multilayer is designed. The newly designed stack is much simple and can be easily made in mass-production scale. Metallic decorative film (Al, Ni and Cr) and colorful decorative film are prepared by magnetron sputtering technique. Based on the analysis of the factors that affect thickness uniformity, some technical parameters related to the film production are adjusted and uniform film is acquired, thus significantly raises the productivity of the deposition of metallic film with high transmissivity on plastic substrates. By analysis of the characteristics of the plastic substrate and utilization of film adhesion theory, the adhesion between Al and substrate is greatly improved in the production of magnetron sputtering metallic Al film. Since metallic film is the outmost layer of the colorful decorative multilayer, compact dielectric film is over coated on its surface to protect the metallic film from the erosion of moister. The addition of the dielectric film can also reduce the stress of the stack, therefore improve the adhesion of the film.