System for producing non-compatible zipper film

Claim 1

A reclosable container, comprising in combination: a bag having confronting flat side walls of a thin film and having an opening between said walls at the top of the bag with said walls attached by a side seam at each side of the bag; reclosable rib and groove fastener strips at the top of the bag between said side walls formed of a thermoplastic material, each strip having an interlocking profile thereon in facing engageable relationship with the opposing profile and having a base secured to the bag wall; a bonding layer between each of the strips and the bag wall coextensive with the strips and located between said base and said bag wall and having a predetermined lateral width, said width being substantially wider than the profile of the strips; and a flattened compressed spot seal at each end of the strips formed of a molten juncture of the plastic of the profiles thereby preventing leakage between the profiles at the seal and locking the profiles in interlocked alignment, said spot seal having a width dictated by the width of the amount of spread which occurs in the plastic of the profiles when compressed to form said spot seal, the width of the bonding layer being greater in both directions laterally of the profiles than said spot seal, the edges of the spot seal being joined to the bag wall by said bonding layer.

Claim 7

The method of constructing a reclosable bag of flexible film comprising the steps: providing a film of bag material to form confronting bag walls; forming a first wall member of the film by feeding a profile strip onto a first section of the film in a position adjacent the location of an opening for a bag to be formed of the film, said strip having a base and a locking profile extending therealong; feeding a bonding layer between the film and the base of the strip with the bonding layer having a predetermined width and adhering the bonding layer to both the film and strip so that the strip is secured to the film; forming a second wall member of the film by feeding a profile strip onto a second section of the film in a position adjacent the location of an opening of a bag formed of the film, said strip having a base and a locking profile extending therealong complementary shaped to the profile of the strip on the first wall member; feeding a bonding layer between the film and the base of the second strip with the bonding layer having a predetermined width and adhering the bonding layer to both the film and strip so that the strip is secured to the film; joining the profiles in interlocking relationship; and applying a localized heat and pressure to the joined profiles at their ends to form a spot seal and spreading the plastic of the profiles against the bonding layer to adhere thereto, the lateral width of said bonding layer being greater than the spot seal so that no leakage can occur between the spot seal and bag walls.

Claim 8

The method of constructing a reclosable bag of flexible film comprising the steps: providing a film of bag material to form confronting bag walls; forming a first wall member of the film by feeding a profile strip onto a first section of the film in a position adjacent the location of an opening for a bag to be formed of the film, said strip having a base and a locking profile extending therealong; feeding a bonding layer between the film and the base of the strip with the bonding layer having a predetermined width and adhering the bonding layer to both the film and strip so that the strip is secured to the film; forming a second wall member of the film by feeding a profile strip onto a second section of the film in a position adjacent the location of an opening of a bag formed of the film, said strip having a base and a locking profile extending therealong complementary shaped to the profile of the strip on the first wall member; feeding a bonding layer between the film and the base of the second strip with the bonding layer having a predetermined width and adhering the bonding layer to both the film and strip so that the strip is secured to the film; joining the profiles in interlocking relationship; and applying a localized heat and pressure to the joined profiles at their ends to form a spot seal and spreading the plastic of the profiles against the bonding layer to adhere thereto, the lateral width of said bonding layer being greater than the spot seal so that no leakage can occur between the spot seal and bag walls.