Methods for forming a thermoplastic film with an attached closure strip are
disclosed. The film can be used to produce zippered reclosable plastic
bags. The methods include providing a thermoplastic film web having a
sealing surface and a closure strip having a binding surface, both being
in a non-melted condition. The film web and the closure strip are aligned
in non-overlapping relationship and a heated thermoplastic binder layer is
positioned on the film web sealing surface and on the closure strip
binding surface quickly after extrusion. The hot binder layer transfers
enough heat to the closure strip and to the film web to melt the closure
strip binding surface and the film web sealing surface. Pressure is
applied to seal the closure strip to the film web. An apparatus for
practicing the method and a reclosable bag formed from the thermoplastic
film with attached closure strips are also disclosed.
