A NEW MORE ECOLOGICAL CLEARING PRODUCT FOR DISPERSE DYES ON POLYESTER/COTTON AND OTHER POLYESTER BLENDS
Our clearing process removes insoluble disperse dyes from the surface of the cotton and polyester fibres, without affecting the soluble reactive dyes that have reacted with cotton (cellulosic) fibres so it can be applied in the dyeing of polyester/cotton and other polyester blends, at the end of the whole process, saving up to:
The process of clearing the excess disperse dye left on the surface of polyester/cotton fibre blends cannot be avoided for most colours, since this dye will later stain adjacent fabric. The process which is usually applied is the reduction clearing process using alkaline sodium hydrosulphite. This is however a very polluting process, due to the high values of CQO and conductivity obtained as a result of its application.
A – sodium carbonate to neutral pH ;
B – reactive dye (dosing) ;
C – Salt ; D –alkali ;
E – ECO-CLEAR
The reduction clearing on blends of CO/PE with sodium hydrosulphite is also a very long process and water intensive, due to the intermediate rinses necessary before dyeing the cotton component with reactive dyes.
Results showed that clearing with ECO-CLEAR is a less polluting, more sustainable, shorter process, and also has better fastness than the alternative reduction clear sequence.