METHOD AND APPARATUS FOR MAKING CONTAINERS FROM THERMOPLASTIC MATERIALS

摘要

A container (5) such as a bottle made of thermoplastic material and provided with a bottom wall having an inwardly convex curved central portion (3) is disclosed. The container is produced by blow moulding a blank (4) with at least one incipient bottom recess (3) in a finishing mould (15a, 15b, 11) of which the bottom wall (11) has an arched central portion (10) substantially matching the recess in the bottom of the container to be produced. Said container is produced by causing relative rotation of the central portion (10) and the blank (4) when said central portion is positioned in the recess in the bottom of the blank.