1. For general light reduction of colorants, pretreatment with the following method will usually remove a significant quantity of color. In the cases of acid and neutral pre-metallized dyes, a reduction strip is usually required.
   • 3.0-4.0 % owg             Soda ash
   • 1.5-3.0 % owg              Orco Nylosol Leveler ACN™

2. Raise temperature to 190-200°F(88-93°C) and run for 30-40 minutes or until desired color reduction is achieved. Cool back to 140°F(60°C) with overflow, drop bath , rinse and re-acidify to a pH of 5.0-6.0. In cases where additional color reduction is required, especially with the fast colors like the metallized groups, the use of a strong reducing agent is necessary :
   • 3.0 % owg      Glacial Acetic Acid 56%
   • 3.0 % owg      Oroxalyde Powder™

3. Prepare the bath with the acetic acid and circulate goods for 5-10 minutes at 125°F(52°).
4. Add the Oroxalyde Powder™ slowly to the bath and raise to the boil over a period of 20-25 minutes. Hold at the boil for 30 minutes, over flow cool to 150°F(66°C) and drop bath.
5. Rinse well first hot then cold to help remove residual reduction chemical.
6. Some dyes undergo a considerable change in color and may still be too dark, thus requiring an oxidative bleach step:
   • 3.0 % owg Sodium Chlorite
   • 3.0 % owg Glacial Acetic 56%

7. Raise temperature back to the boil and hold for 30 minutes.
8. Cool back to 150°F(66°C) and rinse well until all traces of chlorine are removed. The addition of 0.5-1.0 % owg of a suitable antichlor is highly recommended in the last rinse.

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