Patent ID: 8123394

Claim:
A mixer for liquid colorants, comprising: a) a mixing pipe having an outlet opening at an end of the mixing pipe; b) a mixing unit, positioned in the mixing pipe so it is rotatable around the longitudinal axis of the mixing pipe, and having at least two mixing elements, wherein said mixing elements are in the form of helical coils having alternating opposite rotational directions and, when in operation, a portion of said mixing elements move a content of the mixer in a direction towards the outlet opening and a portion of the mixing elements move a content of the mixer in an opposite direction with identical rotational direction of the mixing unit; and c) at least two inlet openings for liquid colorants, which are positioned in a wall of the mixing pipe between ends of the mixing pipe in an area of the mixing unit and wherein the inlet openings for liquid colorants in the mixing unit are positioned so that during a movement of the mixing unit, at least one mixing element of the mixing unit is moved past each of the inlet openings at less than 1 mm distance.