Abstract: An improved method and apparatus is provided for continuously embossing a precision pattern of micro-prismatic elements on a surface of a resinous sheeting material with the aid of an endless metal embossing belt. The method includes the steps of moving the belt along a closed path through a heating station and a cooling station, conveying superimposed resinous film and sheeting material into proximity with the belt, passing the film and sheeting between the belt and a series of sonic welding heads to thereby begin to impress a pattern of micro-prismatic formations of the belt into one surface of the sheeting, pressing the film and sheeting against the heated belt until the one surface of the sheeting fully conforms to the embossing pattern, and stripping the film and embossed sheeting from the belt.