US Patent 7172008 Hook fasteners and methods of making the same

A method of making a touch fastener includes coextruding, side-by-side, a plurality of lanes of polymeric material to form a sheet-form base. The sheet-sheet form base includes a lane of a first polymeric material disposed between two lanes of a second polymeric material, the second polymeric material is different from the first polymeric material. The method further includes molding a plurality of discrete fastener element stems extending outwardly from and integral with the sheet-form base in each of the two lanes of the second polymeric mateial and forming engageable heads on the stems.