are separated by them form an alternating system of thin fluid lamellae wherein in other words fluid lamellae of the medicament solution 11 and fluid lamellae of the precipitation agent 12 are alternately layered fig5 shows a schematic elevation of the structure of a segmenter 2 with the entrance openings 23 and 24 and the outlet opening 26 the precipitation solution 21 which is supplied to the segmenter 2 via the inlet opening 23 is segmented with the help of the transport medium 22 which is supplied through the inlet opening 24 and leaves the segmenter 2 as a two phase flow 25 fig6 shows a second embodiment example of a micro mixer 1 with an integrated segmenter 2 the fluid streams which enter the micro mixer 1 the medicament solution 11 on the one hand and the precipitation agent 12 on the other hand pass through the micro structure 13 of the micro mixer 1 into the mixing chamber 14 and are supplied to segmenter 2 after mixing in the mixing chamber 14 as an extensively homogenous precipitation solution 21 the precipitation solution 21 is segmented in the segmenter 2 with a second fluid which is immiscible with the.