Bleaching of Polyester/Cellulosic blends is typically for the cotton portion of the blend. The goods should be scoured prior to bleaching.
Any processing bath involving rayon should not exceed a pH of 9.0 as it may lead to saponification of the rayon.
- Scour goods in a bath containing 2% owg Orconol CHSA Conc™ and 2% owg tetrasodium pyrophosphate(TSPP) and run at 205°F(96°C) for one hour.
- For heavily soiled cotton, 5% owg of Caustic Soda may be used in place of TSPP, and Orconol CHSA Conc™ should be substituted with Orcoterge ALK-N Conc™ due to the high alkalinity of the bath.
- Drop bath and rinse well.
- In a fresh bath, bleach goods by adding:
- 2.20 % owb Hydrogen Peroxide 35%
- 0.7 % owb Sodium Silicate
- 0.06 % owb Sodium Hydroxide
- 0.5-1.0% owg Orcoterge ALK-N Conc™
- Run goods at 180°F(82°C) for 1 ½ hours.
- Drop bath and rinse until clear.