Cassette for holding and dispensing a roll of web material

Claim 1

A cassette for holding and dispensing a roll of web material wound onto a tubelike core, said cassette comprising a container formed of a tubular shell and two fixed end walls having central hub portions, a tubelike core having a roll of web material wound thereon for rotation therewith, said core having rotatably supported within said container by said hub portions, the shell having a peripheral exit slot through which the web material can be unrolled from said roll, and a rigid locking member for preventing rotation of the core prior to the first use of the cassette, such member comprising two end portions connected by a weakened zone which is ruptured by the rotation of the core incidental to the initial withdrawal of the web material from the cassette, one of said end portions of said locking member being located within and engaged by the core of the roll, and the other end portion being engaged with the hub portion of one end wall of said container so as thereby to prevent rotation of the core, said weakened zone having across its width at least one inner sub-zone of substantially lower rupture resistance than the rupture resistance in each of the outer sub-zones on each side of said inner sub-zone, whereby the rupture resistance of said weakened zone varies across its width and said weakened zone ruptures with significantly lesser relative rotation between said core and hub than in the absence of said inner sub-zone.