Wet Processing
Dose in activity units, not percent. A bath slightly off optimum runs at half the dose the recipe thinks it does.
— %
From the activity actually delivered, not the dose written
Both derating curves are symmetric halving rules, which is a reasonable description near the optimum and a poor one far from it: real enzymes fall away far more steeply on the hot side than the cold, because above the optimum they are not merely slowed but denatured, and that damage is irreversible in a way that a cold bath is not. Treat the cold side of this model as usable and the hot side as optimistic. Weight loss is modelled as saturating on the assumption that the accessible surface is finite, which fits defuzzing well; the deeper hydrolysis that follows once the surface is clean does not saturate and is exactly where strength is lost for no gain in hand, which is why the strength factor is applied linearly to a saturating loss and will understate the damage on a long treatment. Deactivation at the end of the cycle is not modelled and is not optional: cellulase left active on wet goods carries on working through storage, and a batch that measured correctly at the machine can be materially weaker by the time it is inspected. Raise the temperature or the pH decisively to stop it. The removal constant must be fitted on the actual construction - a fine open single jersey and a heavy twill do not respond alike at the same activity.
Cellulase Biopolishing: Activity, Weight Loss & Strength — free, with the formula and a worked example, at Textile School.