Dyeing Procedure of disperse dyes

Disperse Dyes for Polyester Dyeing Method

1. High temperature high pressure dyeing

Polyester and its cotton blends dyeing:

Pretreatment:

Pretreatment of PC or PV is a must before starting the dyeing operation. The pretreatment is essential to remove the lubricant oils and other auxilairies used during spinning and weaving or knitting operations. The following simple treatment is enough to remove those impurities.

    Lissopal D paste = 2 grams/liter
    Soda Ash         = 2 grams/liter
        Treat with the above recipe at 90~95°C for 20 minutes.
2.  Drain - Hot Wash @ 70°C for 10 minutes - Cold wash - Neutralize with 1 cc/liter Acetic Acid.
3.  Check the pH - 5.5 to 6.
                      

Dyeing Process:

Polyester textiles require a Heat Setting operation before dyeing. Heat setting eliminates the internal tensions within the fiber generated during manufacture and the new state can be fixed by rapid cooling. This heat setting fixes the fabrics in the relaxed state and thus avoids subsequent shrinkage or creasing of fabric. Read Heat Setting Process ...

Dyebath Setting & dyeing:

Set up the dyebath with the following auxilaries and chemicals:

  -  Set the dyebath with the above materials. Raise the temperature to 50°C and run for 10 minutes.
  -  Dissolve the dyestuff with soft water at 50°C and filter it.
  -  Add the dyestuff slowly in to the bath. Check the pH to 5.5. to 6.
  -  Raise the temperature to 115°C at 2°C per minute and run 10 minutes.
  -  Raise the temperature further from 115°C t0 135°C at 0.5°C per minute.
  -  Hold for 45 to 60 minutes according to the depth of the shade.
  -  Lower the temperature to 80°C and drain the bath.
  -  Do Hot Wash (70°C) for 10 minutes followed by cold wash.
 
                      

Reduction Clearing:

This is the process to improve the fastness of the dyed material by removing all the dyestuff that is superficially adhearing to the fabric and staining the cotton portion of the blend. The following method is found to be most suitable for any depth of dyeing.

Recipe:

Cyclonon ECO = 2 gpl

Acetic Acid = 2 gpl

Treat the fabric at 70°C for 20 minutes. Do hot wash and cold wash. Drain and unload the batch.

Dyeing process for nylon, triacetate, polyester and acrylic fibers.

At A set bath at 50°

A - Add Auxiliaries & Acetic Acid

At B add Disperse Dyes (pre-dispersed)

2. Carrier dyeing

Carrier dyeing is carried out under atmosphere pressure by an addition of carrier to the dyeing liquor. Methylnaphthalene or chlorobenzene type carrier is used generally, which is added in concentration of 2-7 g/L to the dyeing liquor.
Other conditions of the dyeing liquor are the same as those for high temperature dyeing. The temperature is raised gradually from 40-60°C and continued for 90-120 min at 100°C.
In carrier dyeing, in some case the troubles such as tarring of dye or carrier spot are taken from the no stability of emulsifier in the carrier under high temperature or some other conditions. Therefore, it is necessary to select the carrier so as to prevent the troubles.

Reduction cleaning as stated in high temperature high pressure dyeing.

3. Thermosol dyeing

Thermosol dyeing is a continuous dyeing method which is applied mainly for the polyester/cotton blended materials. General dyeing condition is as follows.

Dye and 0.5-2g/L of migration inhibiter (for example, sodium alginate) and also wetting agent if necessary are added to the padding liquor.

Squeezing is carried out 1dip 1 nip at room temperature, pick up 65-70%. Drying at 70-90_C.

After padding and intermediate drying, thermosol fixation is carried out by dry heating for 60-120 sec. at 180- 210°C depending on the form of the material and type of disperse dyes.

- E type: 180-190°C x 60-120 sec
- SE type: 180-200°C x 60-120 sec
- S type: 200-210°C x 60-120 sec
Reduction cleaning as stated in high temperature high pressure dyeing.