Laboratory padding machine and method for determining the result of dyeing a fabric in a dye bath

摘要

A fabric test sample (B) is fed from an unwinding station (9) through a dye bath (33) and squeeze rollers (26, 27) to a wind-up (10). Injectors (34, 35) top up the bath with dye liquor during the dyeing process according to the volume of dye liquor in the bath (33) as determined by sensors, e.g. by a liquid column. The injectors are actuated by pneumatic pistons and the fabric tension and squeeze roller pressure is adjustable. An Independent claim is also included for the process of dye uptake testing in which the sample is fed continuously through the bath while keeping the liquor volume in the bath constant. The sample is then wound up and the shade compared with the desired color. The processing conditions are set to simulate those encountered on the production machine. The sample is sufficiently long to take up at least one and a half times the bath volume and it has non-absorbent end strips, e.g. of polymer film. After winding up, the sample is sealed from atmospheric influences while any reactions take place.