17/2005 - 2005
A rapid and reproducible dyeing of polyamide with neutral to slightly acid-striking acid or metal complex dyestuffs (levelling dyestuffs) requires an optimum combination of dyestuffs, auxiliaries, time, pH value and temperature.
Even at optimum temperatures, the application of levelling agents, etc. special attention has to be paid to pH regulation. If polyamide is already strongly protonised at the beginning of the dyeing process when dyeing with levelling dyestuffs, accelerated bath exhaustion and unlevel dyeings are inevitable.
Since this can already be possible at a neutral pH range (pH value 7), the pH value in a range of 8 - 9 often has to be arduously adjusted with ammonia or by adding soda ash to avoid positive charges on the fibre at the beginning of the dyeing process.
With the ®RUCO-ACID GBN Bi-Power-System the arduous pH adjustment becomes a thing of the past.Back to list Request brochure