Abstract: A connecting portion is provided between a first thick portion and a second thick portion in a cutting portion. Further, a thinnest portion on which a stress can be concentrated is provided to the connecting portion. Accordingly, when tearing a base material film of a bag body, the connecting portion can guide a cutting line toward the thinnest portion to position the cutting line in the thinnest portion, so that the bag body can be easily opened.

Abstract: A shape-retaining tape and a zipper tape that can be produced only by extrusion molding without using a stretching process, and can retain a prescribed shape by being attached to a package bag formed of a resin film or the like, and a package bag in which these tapes are attached to an opening part. In a zipper tape having an engagement part in which a protruded male part and a recessed female part are engaged with each other, shape-retaining parts formed of a resin composition obtained by adding 0.1 to 40 parts by weight of an inorganic filler relative to 100 parts by weight of a high-density polyethylene resin are provided along the tape-length direction of a male-side belt-like base part and a female-side belt-like base part.

Abstract: A bag body provided with a zipper tape in which both openability by hands and openability by an automatic machine are improved while ensuring the opening strength on the contents side in order to prevent the leakage of the contents is provided. A zipper tape is configured such that the distance A between a front end part of a female part on the non-opening side and a top part on a protruded part on the opening side, the distance B between a front end part of a female part on the non-opening side and a front part opposing to a stripe-shaped base in a protruded part on the non-opening side, and the angle C formed by a protruded part on the non-opening side and a side surface of a shaft part connecting therewith satisfies the relationship represented by the following formula: A?B?0.20 mm and 50°?C?85°.

Abstract: A thick portion is formed thick at an end of a female belt-like base near a containing space. To the thick portion near the containing space, a cut portion thinner than the female belt-like base is provided. To the cut portion near the containing space, a seal base that is thicker than the female belt-like base and is sealed to an inner surface of a bag body to which a male belt-like base is attached, is provided. Seal strength of the thick portion to the inner surface is lower than that of the seal base. The cut portion is provided to have a lower seal strength than that of the seal base. An area surrounded by the thick portion, the cut portion, the seal base and the inner surface becomes hermetically sealed. Even when external pressure is applied on the bag body, damages to the cut portion can be prevented.

Abstract: A connecting portion is provided between a first thick portion and a second thick portion in a cutting portion. Further, a thinnest portion on which a stress can be concentrated is provided to the connecting portion. Accordingly, when tearing a base material film of a bag body, the connecting portion can guide a cutting line toward the thinnest portion to position the cutting line in the thinnest portion, so that the bag body can be easily opened.