TEXTILE WET PROCESSING

DYEING OF COTTON FABRIC WITH DIRECT DYE

         Recipe :

         Percent shade                                    2.0%

         Concentration of glaubers salt          20%

         Concentration of soda ash                 1.5%

         pH of dyeing                                      8.5 to 9.0

         Temperature of dyeing                       98*c

         Time of dyeing                                   60 minutes

         M:L.R                                                 1:30

     Procedure :

     Preparation of Direct Dye solution :

        First weigh accurately 1.0 gm of direct dye powder on a watch glass on a glazed paper and transfer it to porcelain dye pot. Then add 5.0 ml of cold water and 2.0 ml of soda ash solution and stir it well to make the homogeneous paste. Then add remaining 92 ml of boiling water with constant stirring to make total volume 100 ml.

     Dyeing Process :

        First take required ml of water in a dye pot according to M:L.R at room temperature then add 10% glaubers salt, 1.5% soda ash and 2.0% direct dye solution stir it well.

        Enter well weigh scoured cotton fabric in the above dye pot at room temperature and work at this level for 5.0 minutes. Then gradually raise the temperature of dye bath to 98*c and dyeing is continue another 15 minutes. Then add again 10% glaubers salt and continue dyeing process for another 45 minutes. After completion of dyeing take out the dyed material and rinse with cold water and give after treatment.

      After Treatment :

       First take required ml of water in a dye pot according to M:L.R add 2.0% cat-ionic dye fixing agent solution. Then enter the dyed material and raise the temperature of the bath up to 60*c and continue process at this level for 15 minutes. Then squeeze and dry the dyed sample.

      Conclusion :

       from the above process it can be concluded that even shade produced on cotton fabric using direct dye. Washing fastness of direct dye on cotton fabric is poor.