Method and apparatus for making extruded separable fastener with reactivatable adhesive

A method of making synthetic resin resiliently flexible complementary separable fastener profile strips adapted for attachment to film substrate, comprising:

• simultaneously extruding said strips from respective orifices in a common extrusion die;
• applying reactivatable adhesive in fluent state to base surfaces of said strips during extrusion of the strips and before said strips are cured;
• thereafter running the adhesive-carrying freshly extruded strips through a curing zone and therein curing said strips and assuring curing of said adhesive into a nonsticky dormant inactive state so that the strips can be handled without requiring protective cover over the adhesive;
• joining said strips downstream from the curing zone into a separable fastener assembly;
• and then winding the separable fastener assembly into a storage roll for subsequent handling and processing.

A method of making a closure strip adapted to be bonded to a substrate such as film in the manufacture of reclosable bags, comprising;

• extruding in one piece from a polymeric material a closure strip with a longitudinally extending base portion having a longitudinally extending base surface, and a profile portion extending longitudinally parallel with the base portion and having profile means projecting in the opposite direction from that in which the base surface faces;
• shaping said strip cross-sectionally such that a plane projected normal to and bisecting said base surface longitudinally into two parts also bisects the profile portion into corresponding parts;
• in said shaping locating said base surface directly back of said profile portion and providing said base surface of a width essentially no wider than said profile portion;
• and
• adhering a dormant but reactivatable nonsticky adhesive layer to and along said base surface on at least one side of said plane, so that the closure strip is adapted to be bonded to the substrate upon reactivation of the dormant adhesive.

A method of prefabricating a synthetic resin elastically deformable resiliently flexible, separable fastener profile strip adapted for subsequent attachment to a substrate, comprising:

• thermoplastically extruding the strip and providing the extruded strip with a base surface;
• applying reactivatable adhesive in a fluent state to said base surface during extrusion of the strip and before said strip is cured;
• thereafter chill curing the extruded strip;
• concurrently with said chill curing of the strip curing said adhesive on said base surface into a nonsticky dormant inactive state;
• and
• winding the strip into a storage roll in which the nonsticky dormant adhesive on the base surface is in direct contact with nonsticky dormant adhesive on opposing base surface area.

A method of prefabricating a synthetic resin elastically deformable resiliently flexible, separable fastener profile strip adapted for subsequent attachment to a substrate, comprising:

• thermoplastically extruding the strip and providing the extruded strip with a base surface;
• forming a shallow channel in said base surface;
• applying reactivatable adhesive in a fluent state to said base surface in said channel in a layer which is no thicker than spacer and retention ribs extending along the opposite sides of said channel, during extrusion of the strip and before said strip is cured;
• thereafter chill curing the extruded strip;
• and
• concurrently with said chill curing of the strip curing said adhesive on said base surface into a nonsticky dormant inactive state, so that the strip can be stored without protective cover over the adhesive, until used at a later time by reactivating said adhesive to permit adhesively bonding of the strip to a substrate.

Apparatus for prefabricating a synthetic resin elastically deformable resiliently flexible separable fastener profile strip adapted for subsequent attachment to a substrate, and comprising:

• die means for thermoplastically extruding the strip and for providing the extruded strip with a base surface;
• means for applying adhesive in a fluent state to the base surface during extrusion of the strip and before curing of the strip;
• means, downstream from said die means and said adhesive applying means, for curing the extruded strip and concurrently curing said adhesive on said base surface into a nonsticky dormant state so that no cover is needed for the adhesive to permit handling of the strip before its intended use;
• and means for placing said strip and adhesive into condition to be stored until used at a later time by reactivating the dormant adhesive to permit adhesively bonding the strip to a substrate, and this means including handling means directly contacting the nonsticky dormant adhesive.

Apparatus for prefabricating a synthetic resin elastically deformable resiliently flexible separable fastener profile strip adapted for subsequent attachment to a substrate, and comprising:

• die means for thermoplastically extruding the strip and for providing the extruded strip with a base surface;
• means for applying adhesive in a fluent state to the base surface during extrusion of the strip and before curing of the strip;
• means, downstream from said die means and said adhesive applying means, for curing the extruded strip and concurrently curing said adhesive on said base surface into a nonsticky dormant state so that no cover is needed for the adhesive to permit handling of the strip before its intended use;
• and means for placing said strip and adhesive into condition to be stored until used at a later time by reactivating the dormant adhesive to permit adhesively bonding the strip to a substrate;
• said die means comprising multiple closely spaced sets of complementary profile fastener strip extrusion orifices so located that the complementary profile strips can be readily joined into separable fastener assemblies downstream from said curing means.