Container having an improved petaloid bottom, and mould bottom for producing such a container

A mold bottom for a mold for producing, by blow molding or stretch blow molding, containers, made of thermoplastic material PET:

• said containers comprising a body of a substantially cylindrical wall, a shoulder in the extension of said body at an upper end thereof, a neck in the extension of the shoulder, and a bottom of the petaloid type at a lower end of said body, said bottom comprising a wall of generally outwardly convex shape, from which extends at least three feet formed by protrusions which are angularly distributed equidistantly, which feet extend approximately parallel to the axis of the container and which are separated from one another by radiating valleys having a bottom of convex curvilinear radial extent;
• said mold bottom comprising, for the molding of said bottom of the containers, at least three cavities which are angularly distributed equidistantly, which cavities extend substantially parallel to an axis of the mold bottom and which are separated from one another by radiating ridges having a crest of concave radial extent, wherein bottoms of said cavities are distributed over a substantially circular contour corresponding to a base diameter pa of the container, and each cavity having a bottom face which extends in a gentle slope from a central region of the bottom towards the bottom of the cavity;
• wherein a bottom face of each cavity comprises at least two sections, a first central section extending from the central region of the mold bottom in the direction of the bottom of the cavity and having an inwardly facing convexity of the mold bottom, and a second peripheral section extending from the central section to the bottom of the cavity and having an inwardly facing concavity of the mold bottom.

A molding device for producing containers, by blow molding or stretch blow molding, from preforms made of thermoplastic material, said containers comprising:

• a body consisting of a substantially cylindrical wall, a shoulder in the extension of said body at an upper end thereof, a neck in an extension of the shoulder, and a petaloid bottom at the lower end of said body, said bottom comprising a wall of generally outwardly convex shape, from which extend at least three feet formed by protrusions which are angularly distributed equidistantly, which extend approximately parallel to the axis of the container and which are separated from one another by radiating valleys having a bottom of convex curvilinear radial extent;
• and said molding device comprising:
• at least one mold bottom configured to be movably mounted in a lateral wall which defines a cavity with an impression of a part of the container, said lateral wall comprising two half-molds each defining a half-impression of the body of the container and rotatably mounted relative to one another between an open position in which the half-molds are angularly separated from one another and the mold bottom is lowered relative to the half-molds in order to permit the introduction of the preform and the removal of the molded container, and a closed position in which the half-molds are applied against one another and capture between one another the mold bottom, thus to form the cavity and to define the total footprint of the container to be molded, said mold bottom comprising at least three cavities which are angularly distributed equidistantly, which cavities extend substantially parallel to an axis of the mold bottom and which are separated from one another by radiating ridges having a crest of concave radial extent, wherein bottoms of said cavities are distributed over a substantially circular contour.