System and process of molding of plastic materials

A system for moulding plastics material, comprising:

• at least one injection nozzle with a cylindrical tubular body;
• at least one hot chamber on which said at least one injection nozzle is mounted;
• at least one penetrating ram rod which extends coaxially with said injection nozzle;
• at least two passages for supplying the moulding material to said injection nozzle;
• said injection nozzle comprising:
• at least one containing collar;
• at least one injection valve mounted coaxially with said containing collar and having a first end and an opposite supply end;
• said injection valve comprising:
• at least a first injection channel for a first moulding material;
• at least a second injection channel for a second moulding material;
• said first and second injection channels remaining separate as far as said supply end of said at least one injection valve,
• wherein said injection valve comprises i) a cylindrical valve body having a central through hole for said ram rod, ii) at least one flow diffuser keyed on said ram rod and positioned at the first end of said injection valve, and iii) a sealing element, wherein said second injection channel comprises at least three second injection channels which are spaced apart circumferentially and which extend axially along at least a portion of said valve body from said supply end;
• and
• a first circumferential passage to connect said second injection channels.