Cheap, strong sack of tubular textile of woven oriented polymer strips - has box-like end made from folded flaps fixed to inside end of sack by making hole in one flap before bonding with polymer esp. polyolefin melt

摘要

Woven textile sack of monoaxially-oriented polymer esp. polyolefin strips, as in AT400831, consists of tubular fabric or flat fabric bonded to form a tube. One or both sides may be coated with thermoplastic resin, esp. polyolefin, and at least one end of the esp. box-like sack is folded to a rectangular end surface. At least one end is hot bonded to a covering sheet of similar fabric by an intermediate layer of thermoplastic resin, esp. polyolefin, so that only the outer pt. of the surface, esp. less than 30% of the thickness of the strips forming the outer fabric and the flap at the end has polymer mols. disoriented by heating, whilst the rest of the mols. are oriented. The improvement is that at least one of the end flaps formed by folding is fixed to an end surface of the sack on the inside. Also claimed is a method of welding a covering sheet to one end of a sack of this type.