Care should be exercised when selecting Orcocil™ dyes for certain applications due to the limitations of gas-fade properties of some dyes.
For union dyeing(both fabrics with the same shade), Orcocil™ disperse dyes is the recommended dye class. If it is desired to dye the nylon and leave the acetate white, selected acid dyes are recommended. It is very difficult, however, to dye the acetate and leave the nylon white using disperse dyes or acid dyes. A general exhaust procedure for dyeing nylon/acetate blends using Orcocil™ dyes is very similar to that of nylon except for the fact that it is important not to exceed a temperature of 190°F(88°C).
- Properly prepare goods as necessary.
- Circulate for 10-15 minutes in the following chemicals at 110°F(43°C) prior to adding dyes:
- 0.50-1.0 % owg Glacial Acetic Acid
- 1.5 % owg Anionic Wetting Agent
- Add pre-dispersed dyes which have not been exposed to temperatures higher than 160°F(71°C) as many low-energy disperse dyes are sensitive to excessive heat and may precipitate.
- Slowly raise the temperature to 190°F(88°C) at the rate of 2-3°F per minute.
- Continue to run at this elevated temperature for 50-60 minutes.
- Cool back to 150°F(66°C), drop bath and rinse until clear.
- After-fixing low energy disperse dyes does not generally improve the wetfastness to any appreciable degree so it is generally not recommended.
- In many cases a light scour at 120°F with 1.0% owg Orcopon PCA™ will remove loose surface color and improve crocking.
- The use of excessive acid below the pH of 4.5 is not recommended as this may cause precipitation of many disperse dyes.