Abstract A packaging case formed of a boxboard and having annular perforations provided on a wall to enable an opening to be formed when a portion surrounded by the perforations is removed by cutting the perforations. On the wall of the case on which the perforations are provided there is embossed a ruled line extending along the perforations in overlapping relation therewith, by which the strength of the portion of the boxboard in which the perforations are present is lowered so that as the perforations are cut in order to form the opening in the case, the force of tearing is guided by the ruled line along the perforations. By this arrangement the portion surrounded by the perforations can be accurately removed by a relatively small force of tearing and an opening defined by the perforations can be thus accurately formed without the path of the tearing action being allowed to deviate from the perforations.
A case having an annular line of perforations provided on a wall of the case so that an opening can be formed by removing a portion surrounded by the perforations by tearing it off along the line of perforations, comprising a ruled line provided along the line of perforations in overlapping relation therewith, the ruled line being formed by embossing in such manner that it is impressed on one side of the wall so that it projects on the other side of the wall.
Claim 2
Dependent Claim
84 words
A case having an annular line of perforations provided on a wall of the case so that an opening can be formed by removing a portion surrounded by the perforations by tearing it off along the line of perforations, comprising a ruled line provided along the line of perforations in overlapping relation therewith, the ruled line being formed by embossing in such manner that it is impressed on one side of the wall so that it projects on the other side of the wall.
Claim 3
Dependent Claim
80 words
A case having an annular line of perforations provided on a wall of the case so that an opening can be formed by removing a portion surrounded by the perforations by tearing it off along the line of perforations, comprising a ruled line provided along the line of perforations in overlapping relation therewith, the ruled line being formed by embossing on both sides of the wall in such manner that it is impressed into the wall on both sides thereof.
Claim 4
Dependent Claim
80 words
A case having an annular line of perforations provided on a wall of the case so that an opening can be formed by removing a portion surrounded by the perforations by tearing it off along the line of perforations, comprising a ruled line provided along the line of perforations in overlapping relation therewith, the ruled line being formed by embossing on both sides of the wall in such manner that it is impressed into the wall on both sides thereof.