Process of manufacturing an injection mould component

A process of manufacturing an injection mould component for moulding the external surface of a preform neck made of plastic material, the injection mould component comprising

• a pair of half-inserts defining, when assembled in the injection mould, a moulding surface of said external surface of the neck;
• said moulding surface defining a longitudinal axis and comprising a first annular groove for making a first annular flange of the preform neck;
• a cylindrical end portion, arranged at a first side of said first annular groove, for making a corresponding cylindrical end portion of the preform neck;
• and a portion proximal to said first annular groove and arranged at a second side of said first annular groove, for making a corresponding portion proximal to the first annular flange,
• wherein each half-insert is provided with an internal circuit for the passage of a cooling liquid;
• said internal circuit being provided with
• a first curved stretch and a second curved stretch provided in proximity of said first annular groove of the moulding surface;
• a third curved stretch provided in proximity of said cylindrical end portion of the moulding surface;
• a fourth curved stretch provided in proximity of a portion of the moulding surface;
• wherein the third curved stretch and the fourth curved stretch are branches of said first curved stretch and converge in said second curved stretch,
• wherein the first curved stretch and the second curved stretch have a respective curvilinear axis, arranged on a first plane which is substantially perpendicular to a plane containing the longitudinal axis of the moulding surface, and are symmetrically arranged with respect to a centre-line plane Z of the half-insert,
• wherein the third curved stretch has a curvilinear axis arranged on a second plane and the fourth curved stretch has a curvilinear axis arranged on a third plane, said second plane and third plane being substantially parallel to said first plane,
• and wherein said first, second and third planes are three distinct planes,
• wherein each half insert consists of two parts integrally connected to each other,
• wherein a first part of said at least two parts comprises the first curved stretch, the second curved stretch, the third curved stretch and the fourth curved stretch,
• the process comprising the production, starting from metal powder, of at least said first part by means of Sintering Laser Melting or Laser Cusing.