Disperse Tinting for Polyester Woven Fabric in Stenter Machine for Overprinting Order (A practical approach)


Apart from theoretical understanding of dyeing, a practical approach is necessary to get desired outcome in dyeing operation. The detail technique based on the experiments is mentioned below, which would increase productivity side by side with lower costs and with lesser consumption of water. .


In order to get the maximum shades, in case of Polyester woven fabric dyeing (Exhaust method); it is advisable to maintain the temperature between 130-135 degree Celsius. For Example: - Jet dyeing machine is common for polyester woven and knitted fabric dyeing. However, it is advisable to maintain Temp between 100-105 degree Celsius (carrier method) to get selected light and medium shades only.


Stenter method for polyester dyeing;-


1) Thermosol method:


In this method, it is advisable to maintain temperature between 190-205 degree Celsius, as selection of dyes is very important. High sublimation fastness of dyes is required, however commercially exhaust method is highly accepted.


2) Carrier method:


In this method, it is advisable to maintain the temperature between 150-160 degree Celsius, and hence selection of dyes is also very important.


Printing order on dyed ground (some pastel shade) directly in bulk method


In Stenter following points should be considered before going for padding method:-


  1. Center side variation:

    In stenter padding, maximum two sides only air pressure arrangement is maintained (Left hand side and right hand side).

  2. M/c should be cleaned properly otherwise there will be some chances of stain or patchiness.

    With consideration of all points, light pastel shade should be selected for printing in 90 % design to prevent any problems. Hence, the pastel shade can be converted to medium or dark shade.


Normal process:


Exhaust dyeing drying and batching printing in rotary machine loop ager soaper m/c washing drying and finishing.


New Process (Experiment):


Stenter padding drying and batching printing in rotary machine loop ager soaper m/c washing drying and finishing.

                       

 

                                  

In Stenter machine padding method following chemicals are used:-


  • Dye: - X gpl (Refer Fig 1. Dye was dissolved in hot water)
  • DFT: - 0.5 gpl. (Leveling agent and dispersing agent both are included)
  • Carrier: - 2.0 gpl
  • Sodium aliginite: - 2.0 gpl (Ph is adjusted to 4.5 with acetic acid and buffer solution)
  • Drying and Dyeing temp: - 150-160 degree Celsius at speed (Time of contact)


Process used: - pad-drying and baking. (No washing was done because fabric is going for 90% coverage design printing purpose. After printing process is completed that include complete (from printing-drying-loop ager m/c for ageing) then it goes continuous soaper machine for final washing. Here we are concentrating only on dyeing process.


  • %pick up (Light and right hand side mangle): - 61.87%
  • Speed (meter/minute):- 10-15 meter/minute.
  • Fabric: - Polyester micro woven fabric.
  • Recipe of all bulk trails ( Refer figure 1- Light orange, yellow, violet and blue shade recipe has been written in scanned photo)
  • Light violet: - Disperse violet S3RL=0.3 gpl
    • Disperse Red BEL=0.2 gpl
  • Light Yellow: - Disperse Yellow 4G=0.06 gpl
  • Light Green: - Disperse Blue FBLN=0.36 gpl
    • Disperse Yellow 4G=0.05 gpl
  • Light Blue: - Disperse Blue FBLN=1.4 gpl


Conclusion:


A practical approach in case of Pastel shades would definitely increase productivity gradually, side by side cheaper cost with less consumption of water.


Benefits of suggested Process:


  • Water saving
  • Less time for dyeing
  • Thermal energy saving