Embossed monolithic polymer film and process of forming the same

摘要

A thermoplastic film formed of a monolithic polymer and which is embossed. The film has an embossed height of h, a material thickness of t1 at the apex of the embossed height h, and a material thickness of t2 at the base of the film. The film also has a concave cavity below the apex of the embossed height h. The monolithic polymer film is formed using a screen with a perforated pattern. A monolithic polymer is extruded onto the screen in semi-molten film. The screen is rotated such that the film passes over a vacuum slot behind the screen. A vacuum in the vacuum slot pulls the monolithic polymer into the perforated pattern of the screen without perforating the film. The perforated pattern of the screen is transferred to the monolithic polymer film as the film passes over the vacuum slot.