It is very important that the cellulosic goods to be dyed are free of any processing chemical additives such as sizes, waxes, oils, peroxide, chlorine, or natural contaminates. Do not exceed a pH of 9.0 when bleaching rayon as this will initiate saponification. Bleaching processes may not be necessary for dull, earthtone, dark, navy, or black shades.
Pre-Scour
- Enter goods in bath containing:
- 2.0% Soda Ash on weight of goods(owg)
- 2.0% owg Orcoterge ALK-N Conc™
- 0.5% owg Orco Penetrant 120™
- Raise temperature to 185°-195°F(90°-93°C) and hold for 30 minutes.
- Drop bath and rinse well.
Half-Bleach Bottom Procedure
Half-Bleach bottoms may be desired for pastel and bright shades where a full-bleach is not necessary.
- Enter goods into a bleaching bath containing:
- 3-4 % owg Hydrogen Peroxide 35%
- 1.0-1.5 % owg Sodium silicate
- 0.5 % owg Sodium Hexametaphosphate
- 0.5-1.0 % owg Sodium Hydroxide
- 1.0 % owg Orcoterge ALK-N Conc™
- Raise temperature to 185°-195°F(85°-91°C) and run for 1 hour.
- Drop bath, rinse well, adjust pH to 6.5-7.5 and dry.
Full-Bleach Bottom Procedure
For a cleaner white on cellulosics a full-bottom bleach procedure may be required. This requires a higher amount of Hydrogen Peroxide and an optical whitener may be included in the bleaching bath to enhance the white.
- Enter goods into a bleaching bath at 80°-100°F(26°-38°C) containing:
- 4-8 % owg Hydrogen Peroxide 35%
- 2-4 % owg Sodium silicate
- 0.25-0.5% owg Caustic Soda 50%
- 0.25% owg Peroxide Stabilizer
- 0.5 % owg Sodium Hexametaphosphate
- 0.5-1.0 % owg Sodium Hydroxide
- 0.5-1.0 % owb Orcoterge ALK-N Conc™
- 0.75-1.0 % owg Orco Synthrowite C-ALKS™
- Raise temperature to 185°-195°F(85°-91°C) and run for 1 hour.
- Drop bath, rinse well, and adjust pH to 6.5-7.5 .