Abstract: The invention relates to a mold base (1) for a mold that is used for the blow molding or stretch-blow molding of thermoplastic containers (2) having a petaloid-shaped base. The mold base (1) includes several cavities (11) separated by radiating ridges (13) with concave crests (14), the bases (15) of the cavities (11) being distributed along a circular contour. As seen radially on either side of the deepest point thereof, each cavity (11) is defined towards the exterior by a curved surface portion (18) having a circular arc radial cross-section and towards the interior by a broken-plane surface portion (19) with at least two slopes that intersect the curved surface portion (18) at a straight edge (20). The plane (T) which contains the aforementioned edge (2) and which is tangent to the curved surface portion (18) is perpendicular to the axis (12) of the mold base.

Abstract: A thermoplastic container, in particular a bottle, made by blow-molding or stretch blow-molding of a heated preform and including a bell-shaped convex base with its concavity facing outward and provided with reinforcing impressions projecting inward and radiating around a central recess, the impressions having a trapezoid shape with its smaller dimension located toward the center of the base; the impressions include respective arches which form convex trapezoid segments with concavity facing inward and extending from the seat to the central recess by being connected thereto immediately proximate the upper end of the central recess.

Abstract: The invention concerns a mold base (1) for a mold for blow- or stretch-blow molding thermoplastic containers with petal-shaped base; the mold base (1) comprises several cavities (11) separated by radiating ridges(13) with concave crest surface (14), the bases of the cavities (11) being distributed in a circular outline; the crests (14) of the ridges extending in an arc from the center of the molding cavity (C); each zone (18) intermediate between two consecutive ridges (13) and a corresponding cavity (11) is flat in a plane (P) perpendicular to the axis (12) of the mold base (1); advantageously the cavities (11) are arc-shaped in the diametrical cross-section of the mold base.

Abstract: The invention relates to a mould base (1) for a mould that is used for the blow moulding or stretch-blow moulding of thermoplastic containers (2) having a petaloid-shaped base. The mould base (1) includes several cavities (11) separated by radiating ridges (13) with concave crests (14), the bases (15) of the cavities (11) being distributed along a circular contour. As seen radially on either side of the deepest point thereof, each cavity (11) is defined towards the exterior by a curved surface portion (18) having a circular arc radial cross-section and towards the interior by a broken-plane surface portion (19) with at least two slopes that intersect the curved surface portion (18) at a straight edge (20). The plane (T) which contains the aforementioned edge (2) and which is tangent to the curved surface portion (18) is perpendicular to the axis (12) of the mould base.

Abstract: The invention relates to the production of containers (2) comprising a narrow opening and a long body, such as bottles or similar, from polypropylene by means of blow moulding or stretch blow moulding. According to the invention, during the blow moulding or stretch blow moulding step, the polypropylene preform (1) undergoes longitudinal stretching at a ratio (L/1) of between approximately 2 and 3.5 and radial stretching (D/d) at a ratio of between approximately 2 and 3.