Abstract: The cap assembly comprises: a cap which when unscrewed causes a detachment or distancing of a safety strip from the cap; and a convex seal which, when the cap assembly is inserted on a bottle, is deformed by internal pressure in the bottle and guarantees a seal on an internal wall of a bottle neck, even when there are small axial movements of the cap assembly with respect to the bottle neck.

Abstract: The invention relates to a plastic bottle cap in two parts. The first part (1) of said cap is annular-shaped and exhibits on its external lateral surface a plurality of projections (5), while the second part comprises a screw-up (2) inferiorly to which is connected a breakable seal (4) by means of easy-breaking webs (6); the cap exhibits a plurality of teeth (7), arranged parallel to the webs (6), which, on first screwing-on of the cap on to the bottle, are inserted between the projections (5) of the first part (1) and bear the forces which are generated during the screwing-on; since the teeth (7) are not connected to the breakable seal, the teeth (7) do not obstruct the detachment between the bottle-top and the breakable seal (4) when the cap is first unscrewed.

Abstract: The one-piece twist-off bottle top, used mainly for fizzy or still soft drinks, has a deformable break-open seal (2) that features a succession of recesses (4) exhibiting oblique pyramidal shape. When the top is fitted initially to the bottle, certain of the surfaces of these pyramids are urged gently outward so that the internal diameter of the seal can be enlarged; when the cap is first twisted off, other surfaces are designed to resist on coming up against an annular bead (9) offered by the neck of the bottle, in such a way that the cap and seal are forced to separate.