Application direct dye on rayon fabrics

  Application of direct dye on rayon fabrics

Direct dye is a sodium salt of sulphonic acid of different compounds. This dye contains azo structures. This dye has more affinity to cotton fiber so it is called a direct cotton color. The direct dye can be directly absorbed by viscose rayon from a simple dye solution.  This is a substantive dye. Due to more affinity to cotton or cellulosic fiber, this dye is named substantive dye. 

Now I am going to describe the process that how to apply direct dye on viscose rayon fiber or fabric. 

Viscose rayon is one kind of regenerated cellulose fiber. This fiber has a strong affinity to direct dye. This dye has good fastness on viscose rayon fiber. 

The recipe is given below: 

Direct dye: 1-4% based on the weight of the fabric.

Soda Ash: 1-3% based on the weight of the fabric.

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

Water: 20 times the weight of fabrics.

Time: 45-60 minutes.

Temperature: 50-60°.

Dyeing process: 

First of all, we need to take dyes in normal water and mix it well then we need to add some boiled water to make a dye solution. Then need to take the fabrics where we want to dye the fabrics. then take water and then need to give the dye solution in the dye bath and mix it well at 40°C.  After that, we need to add Sodium carbonate and mix it well and rise the temperature to 40°C. Slowly rise the temperature up to 50°C and use half a quantity of salt in the dye bath add fabrics in wet condition to the dye bath and run the machine for up to 30 minutes. After that, we need to load the fabrics and again give the rest quantity of the salt and mix up well. After that, we need to rise the temperature to 60°C and again process for 30 minutes. After that, we need to unload the fabrics and dry the fabrics.