Manufacture of multi-wall bag having heat-sealed liner

Claim 1

A METHOD FOR CONTINUOUSLY FORMING MULI-WALL BAGS HAVING AN INNER LINER COMPOSED OF HEAT SEALABLE MATERIAL, SUCH AS POLYTHYLENE, WHICH COMPRISES ADVANCING A PLURALITY OF PAPER WEBS AND A PREFORMED TUBE OF LINER FORMING MATERIAL, SUPERPOSING SAID PAPER WEBS AND SAID LINER TUBE WITH SAID LINER TUBE OVERLYING SAID PAPER WEBS AND SPACED INWARDLY FROM THE OPPOSITE SIDE EDGES THEREOF, CONCURRENTLY INFOLDING THE OPPOSITE SIDE EDGES OF SAID PAPER WEBS ABOUT SAID LINER TUBE AND JOINING TOGETHER THEIR CORRESPONDING EDGES TO PROVIDE A PLURALITY OF TUBES LYING ONE WITHIN THE OTHER, WITH SAID LINER TUBE INNERMOST, SEVERING SAID COMBINED TUBES CROSSWISE INTO BAG LENGTHS, AND THEREAFTER ADVANCING SAID BAG LENGTHS SO FORMED IN A DIRECTION AT RIGHT ANGLES TO THEIR LENGTH, CLOSING THE ENDS OF SAID BAG LENGTHS BY HEAT SEALING AT LEAST ONE END OF EACH INNER LINER THROUGH THE SURROUNDING PAPER TUBES TO FORM AN END SEAL FOR SAID LINER TUBE AND CLOSING THE CORESPONDING ENDS OF SAID SURROUNDING PAPER TUBES BY A LINE OF STITCHING EXTENDING ALONG MARGINAL END PORTIONS OF SAID SURROUNDING TUBES AND PASSING COMPLETELY THROUGH ALL OF THE PLIES OF SAID BAG LENGTH INCLUDING SAID INNER LINER, SAID LINE OF STITCHING PASSING THROUGH THE SEALED END OF SAID LINER TUBE ALONG A LINE SPACED OUTWARDLY FROM THE INNERMOST EDGE OF SAID END SEAL, WHEREBY SAID LINE OF STITCHING SECURES SAID INNER LINER TO THE SURROUNDING PLIES OF THE BAG SO FORMED AND YET DOES NOT INTERFERE WITH THE SEALED CONDITION OF SAID INNER LINER.

Claim 2

A METHOD FOR CONTINUOUSLY FORMING MULI-WALL BAGS HAVING AN INNER LINER COMPOSED OF HEAT SEALABLE MATERIAL, SUCH AS POLYTHYLENE, WHICH COMPRISES ADVANCING A PLURALITY OF PAPER WEBS AND A PREFORMED TUBE OF LINER FORMING MATERIAL, SUPERPOSING SAID PAPER WEBS AND SAID LINER TUBE WITH SAID LINER TUBE OVERLYING SAID PAPER WEBS AND SPACED INWARDLY FROM THE OPPOSITE SIDE EDGES THEREOF, CONCURRENTLY INFOLDING THE OPPOSITE SIDE EDGES OF SAID PAPER WEBS ABOUT SAID LINER TUBE AND JOINING TOGETHER THEIR CORRESPONDING EDGES TO PROVIDE A PLURALITY OF TUBES LYING ONE WITHIN THE OTHER, WITH SAID LINER TUBE INNERMOST, SEVERING SAID COMBINED TUBES CROSSWISE INTO BAG LENGTHS, AND THEREAFTER ADVANCING SAID BAG LENGTHS SO FORMED IN A DIRECTION AT RIGHT ANGLES TO THEIR LENGTH, CLOSING THE ENDS OF SAID BAG LENGTHS BY HEAT SEALING AT LEAST ONE END OF EACH INNER LINER THROUGH THE SURROUNDING PAPER TUBES TO FORM AN END SEAL FOR SAID LINER TUBE AND CLOSING THE CORESPONDING ENDS OF SAID SURROUNDING PAPER TUBES BY A LINE OF STITCHING EXTENDING ALONG MARGINAL END PORTIONS OF SAID SURROUNDING TUBES AND PASSING COMPLETELY THROUGH ALL OF THE PLIES OF SAID BAG LENGTH INCLUDING SAID INNER LINER, SAID LINE OF STITCHING PASSING THROUGH THE SEALED END OF SAID LINER TUBE ALONG A LINE SPACED OUTWARDLY FROM THE INNERMOST EDGE OF SAID END SEAL, WHEREBY SAID LINE OF STITCHING SECURES SAID INNER LINER TO THE SURROUNDING PLIES OF THE BAG SO FORMED AND YET DOES NOT INTERFERE WITH THE SEALED CONDITION OF SAID INNER LINER.