APPARATUS FOR FORMING A GUIDE RIB ON A SECTION OF PLASTIC FILM

摘要

A method and apparatus for forming a rib on a section of plastic film utiliz es a roll having a groove, extrudes molten polymer into the groove, and places the section of plastic film in contact with the molten polymer in the groove. The molten polymer in the groove is allowed to cool below the melting point thereof while the section of plastic film is in contact with the polymer to cause bonding therebetween and thereby for m the rib.