Patent GB-1219977-A (GB)
Title: Improved container
Inventor: WHITE ARTHUR JOHN
IPC: B65D3/26
Filed: 1968-06-06
Abstract: 1,219,977. Opening containers. AMERICAN CAN CO. 6 June, 1968, No. 26920/68. Heading B8D. A container 10 includes a side wall 12 openable along a line of separation, and a liner ply 36 underlying the side wall and having marginal side portions joined to one another in a lap joint J which is contiguous to the line of separation. In one embodiment, an inner body ply 22 is adhered by an adhesive layer 24 to an outer body ply 26 and the latter is joined by an adhesive bond 28 to a label ply 30. A liner ply 36 is adherent to the inner body ply by an adhesive coat 34. The liner ply has a marginal hemmed portion 38 which is folded outwardly to have an inner, 39, and an outer, 40, hem layer, the former of which is joined to the opposing marginal portion 45 of the liner ply by an adhesive bond 44, preferably of low peel resistance, to form the lap joint. A portion of a pull string 16 overlies the lap joint and is interposed between the side edges 46, 48 of the inner body ply. The remaining end of the pull string lies just beneath the label ply at one end of the container and is partially exposed for operation. The container wall may be spirally wound and the side edges of the inner body ply define a spiral line of separation along which the container opens when the string is pulled. Top 14 and bottom 15 end members may be secured to the side wall in clinched seams. The marginal portion 38 of the liner ply may not be folded (Fig. 6, not shown), being joined instead to the opposing marginal portion of the liner ply by an adhesive bond 44 of preferably low shear resistance. There may be only one body ply by the omission of either the inner or the outer body ply of the first embodiment. In the former case, the pull string is positioned inside the single body ply in contact with the outer hem layer and in the latter case it is positioned between the side edges of the body ply 22, a label ply of sufficient strength being provided to retain the side edges adjacent to each other. The container may have no pull string, being then opened by ripping or peeling off the outer body ply to expose the line of separation. The container is described as enclosing a biscuit dough and baking powder mixture P, the pressure of which is contained by a partial peeling or stretching of the lap joint. After pulling the string or peeling or ripping off the outer body ply, the pressure of the mixture causes the container to open along the line of separation by completely peeling or shearing the lap joint and forming a spiral opening 50 (Fig. 4, not shown). The mixture pushes the outer hem layer through the opening (Fig. 5, not shown) and is subsequently made completely accessible by twisting the end members in opposite directions. The liner ply may be made of a homogeneous layer of a moisture impervious material, for example a polythene or other plastics film, aluminium foil, or other metallic foil or "greaseproof" paper. Alternatively, it may be made of two or more laminated layers so that the innermost layer is of water impervious material and the outer layer is of a cheaper material such as kraft paper.