Wet Processing
High exhaustion with poor fixation looks like success in the machine and fails in the wash test.
— %
Dye that left the bath and entered the fibre
—% fixed —% lost
Reactive dyes on cotton typically fix 60-80% of what is applied. The unfixed balance is hydrolysed dye that loads the effluent and must be soaped off.
Dye Exhaustion & Fixation Percentage Calculator — free, with the formula and a worked example, at Textile School.