초록

A hollow container of molecularly oriented thermoplastic material having a generally cylindrical form and provided with a base constituted by a series of annular toroidal sections of semicircular cross section and having alternating directions of curvature.

대표청구항 ▼

In a hollow body made of an oriented thermoplastic material, which body is of generally cylindrical shape and includes a base and a side wall, the improvement wherein said base is oriented and is constituted by between three and 15 concentric annular toroidal sections of substantially semicircular c

In a hollow body made of an oriented thermoplastic material, which body is of generally cylindrical shape and includes a base and a side wall, the improvement wherein said base is oriented and is constituted by between three and 15 concentric annular toroidal sections of substantially semicircular cross section and having alternating directions of curvature from the periphery of said body inwards wherein the radially outermost one of said base sections is upwardly concave and joins directly onto said side wall of said hollow body and the diameter of the cross section of each of said annular sections is less than 20% of the maximum diameter of said side wall.