In generals terms the article wouldn't requires a preliminary treatment. But to remove the grease or the remains of production we suggest to use a aqueous solution of NEWDET-100 (10%) at 40°-50°Rinse in flowing water.

Dyeing:

• to suspend colouring dye in lukewarm water 3-6 g/litter
  

• add the carrier POLIDISPERD/N 2 ml/litter (to obtain a major colouring dye solubility you can   add 0,5% of acetic acid)

• boil the bath and plunge the buttons

• after the dyeing, rinse in flowing water

About the colours in excess, that it's not fixing on the material, you can diluite 2g-/litre the DETERGENTE PON with neuter-bath or weakly-acid, increase the temperature a 30°-40°C, for about 5-10 minute, than rinse.