초록

Unitary double cavity cartons, for example, of the type commonly referred to as clam shell cartons, are provided in which lines of weakness, adjacent the center hinge and positioned to form a hinge ridge or channel upon closing, permit the carton to open freely without buckling or tearing.

대표청구항 ▼

In a double cavity paperboard carton formed of a single cut and scored blank having a bottom cavity portion and a top cavity portion wherein each of the bottom and top cavities comprise hingedly connected front, side and rear walls adhered through suitable glue tabs, and the top and bottom cavities

In a double cavity paperboard carton formed of a single cut and scored blank having a bottom cavity portion and a top cavity portion wherein each of the bottom and top cavities comprise hingedly connected front, side and rear walls adhered through suitable glue tabs, and the top and bottom cavities are hingedly connected through a center hinge line connecting their respective rear walls, the improvement which comprises provision of a fold area on said carton rear wall adjacent said center hinge line within which folding is controlled without buckling or outward bowing, said area being selected from the group consisting of (1) a hinge ridge defined by a member selected from (a) at least one line of weakness adjacent and parallel to said center hinge on either side thereof; and (b) an offset cut score or knife cut at the center of said center hinge; and (2) a hinge channel defined by at least one line of weakness on each side of said center hinge.