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How to cotton fiber is color or printed


We know that, for cotton printing many processes is used. Here I am describing the one Rotary-screen printing. Rotary-screen printing machines make use of the same principle described earlier, but as a substitute of flat screens, the color is transfer to the fabric through frivolous metal foil screens, which are made in the form of cylinder rollers. The fabric move along in continuous mode under a set of cylinder screens while at each position the print paste is automatically feed to the inside of the screen from a tank and is then pressed through onto the fabric. A separate cylinder roller is required for each color in the design.
A conventional paste feeding system for rotary-screen printing machines is represented in Figure suction pipe leads from the paste vat to a pump, from where a printing hose leads to the squeegee (dye pipe with squeegee). From here the paste is directed inside the cylinder roller. Rotary-screen printing machines are equipped with both gluing and washing devices analogous to those described earlier for flat-screen printing. The belt is washed in order to remove the residues of paste and adhesive. Not only the belt, but also the screens and the paste input systems (hoses, pipes, pumps, squeegees, etc.) have to be cleaned up at each color change.

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