SHRINK TUBE WITH CUTTING LINE SHOWING SUPERIOR ANTI-BAG BREAKAGE

摘要

PROBLEM TO BE SOLVED: To improve a bag unbreakable characteristic of a shrink tube having a cutting line while keeping a superior cutting characteristic of the cutting line. SOLUTION: This cutting line (1) is comprised of a row of small perforations (2) having a thick walled hole edge (21 ). The perforations in a surface area A facing a constriction (23) of a container have a smaller hole diameter (d2 ) or a larger hole pitch (p2 ) as compared with that of perforations in a surface area (a surface area other than A) except an outer surface area. At a stage for heat shrinkage processing for installing this tube to the container, although the surface area A produces a large heat shrinkage deformation, it may produce a reinforcement and strength because the hole edge (21 ) of each of the small perforations (2) has a thick wall; a high unbreakableness as an effect of adjustment of the hole pitch (p2 ); and a neat installed finish state without producing any breakage of the tube. The cutting line (1) can be formed efficiently through a laser beam radiation work.