US Patent 7128561 Surface treatment for blanket of thermoplastic fibers

An apparatus and method are provided for forming a densified surface layer on a thermoplastic blanket. The apparatus includes first and second continuous belts, a treatment zone defined between those belts, first and second heating and densifying units and a cooler downstream from the heating and densifying units. The method includes the steps of continuously forming a densified surface layer on a face of a thermoplastic blanket and making the thermoplastic blanket with the densified surface layer to a desired thickness within strict dimensional tolerances. A densified thermoplastic blanket product is also disclosed.