Molten resin material is continuously extruded from an extruding hole including a plurality of engaging-element-molding portions disposed with a constant pitch in a width direction of an extruding nozzle and a substrate-molding portion with which lower ends of the engaging-element-molding portions communicate....http://www.google.com/patents/US6209177?utm_source=gb-gplus-sharePatent US6209177 - Molded surface fastener, and molding method and molding apparatus of the same
