Sack of plastics material with internal fastener and base covering sheet and method of making same

摘要

A sack made from a tube of plastics material has its bottom constructed by folding an end portion of the tube so as to form two coplanar substantially isosceles triangular flattened portions with spaced confronting bases defined by plain edges and sides defined by fold lines. The space between the bases is bridged by a strip of material that overlaps the bases of the triangles and also projects beyond the base angles of the triangles. The projecting ends of the strip are folded over and the strip is welded to the sack bottom by seams which intersect at the fold lines.