Insoluble sulpher dye used on cotton

  Insoluble Sulpher dye used on cotton : 

Dye solution making is an important work in dyeing. First of all, we need to take some normal water and mix some dyes and make a dye paste. After that with this paste need to add some necessary quantity Na2S and add some water in it. After that also need to add some boiled water also in it make a solution for 10 minutes. In another pot, we need to add some water and then pour the dye solution into it. Next, add some necessary quantity of Soda Ash. After these processes need to add cotton fabric in the dye bath and raise the temperature. Need to add salt to increase dye exhaustion. In this way, it is necessary to add 1.5 hours of continuous dyeing. In this dyeing process, we can use the below dyes. 

Thionol yellow Yn 

Thionone orange S New,

Eclipse violet brown K,

Pyrogen pure blue 3CL,

Thionol sky blue 6B,

Eclipse brilliant green 3G,

Sulphanol olive TR,

Bolfo brown GR,

Sulpher black,

Thionol black GR. 

Recipe of  insoluble sulpher dye: 

Dyestuff: 8-10% based on the weight of the fabric.

Sodium Sulphide: 10-15% based on the weight of the fabric. 

Soda Ash: 5-10% based on the weight of the fabric. 

General salt: 10-20% based on the weight of the fabric. 

TR oil: 1% 

Water: 30 times based on the weight of the fabric. 

Temperature: 90-95°C 

Time: 60-90 minutes. 

Solution making: Sulpher dye is insoluble in water so we need to make it soluble. For this purpose, we need to use TR oil in some water and make a paste. After that there need to add some hot water and Na2S and make the solution. After that need to prepare dye bath. Then need to take water as per recipe and add Soda Ash and mix well. Previously made dye solution need to add in dye bath and mix up well and then the dye solution is ready to dye the cotton fabric. 

                              2H 

Dye-S-S-Dye         →   Dye-SH+ HS-Dye 

Dyeing process: Previously made dye solution needs to add cotton fabric and raise temperature. When the dye bath temperature is 50-60°C then need to add 50% salt of the recipe. Then mix and again need to raise the temperature up to 90°C -95°C and add the rest of the salt and dye for one hour. After dyeing is complete we need to wash the fabric by water. 

After treatment: After treatment is a very necessary process in fabric dyeing technology. Because based on this process dye is ripened.  Here by this process we fix up dyes on cotton and wash and remove unfixed dyes. Sulpher-dyed fabric can be after treatment in 2% soaping solution and after sinking needs to wash in normal water and dry in sunlight and air.