Production of stamped plastic sheet

摘要

A stamped plastic sheet manufacturing method includes immersing a molten extruded thermoplastic sheet into a liquid refrigerant just prior to passing through a pair of stamping rolls having tooth-like or vane-like projections. In this manner, a skin layer is formed on the surface of the molten plastic sheet prior to stamping. Upon stamping, the sheet is tensioned by the confronting crests of the above tooth-like or vane-like projections and then removed from the liquid refrigerant after the interior of the sheet has been hardened to form a stamped sheet having a substantially uniform thickness.