摘要 |
This invention relates to a sack made of fabric consisting of monoaxially drawn, desirably single-layer, tapes of polymer, particularly polyolefine, preferab ly polypropylene, which fabric may be coated on one or both sides with a thermoplastic material, particularly polyolefine, wherein the fabric is a seamless tubular fabric or a flat fabric combined to form a tube and at least one end of the sack having in particular the shape of a box or a right parallelepiped is formed by folding the fabric end s to a particularly rectangular bottom surface. The present sack is characterized i n that at least one end of the sack, particularly a bottom surface, is bonded, via an intermediate layer particularly made of thermoplastic, particularly polyolefine, preferably polypropylene material, and by means of heat, to a cover sheet made of fabric consisting o f monoaxially drawn tapes of polymer, in particular polyolefine and preferably polypropylene, and in that only the external surface area, in particular les s than 30% of the material thickness of the fabric tapes, includes disoriented polymer, in particular polyolefine and preferably polypropylene, molecules due to the heat, wherein in the rest of the material area the molecules are oriented. The invention also relates to a process for welding a cover sheetonto a bottom surface of the sack. |