Printing of 100% cotton fabric with reactive dyes screen printing.

 Experiment No : 08.

Experiment Name:

Printing of 100% cotton fabric with reactive dyes  screen printing.

Introduction:

By the term textile printing we mean the localized application of dyes or pigment and chemical by any method, which can produce particular effect of color on the fabric according to the design. In this practical we print cotton fabric with cold brand reactive dyes in block and screen printing methods in combination method

Objective :

•  
• 1.Understand the properties of reactive dyes.
• 2.Learn the preparation of cotton fabric for screen printing.
• 3.Master the technique of screen printing with reactive dyes.
• 4.Analyze the post-printing treatment processes to enhance colorfastness.

Raw Materials: 100% cotton woven fabric.

Chemical Required:            

                Dyes 
                Urea 
                Thickener 
                Resist salt 
                Soda ash 

Apparatus Required :

•       Beakers.
•         Glass Rod.
•       Pipette.
•      Digital Balance.
•      Pot.
•     Air dryer.

Recipe:

              Dyes = 4gm
        Urea = 10gm
        Thickener = 50gm
        Resist salt =1gm
        Soda ash = 6gm
        Additional water = as required.   

Preparation of printing paste:

•  At first we take required amount of dyestuffs in a bath.
  

• Then little amount of water is added into the bath for mixing these dyes.

• Then required amount of urea is added into the dye bath.

• After then required amount of thickener is added

• Then continuous stirring is done for few minutes for mixing all the ingredients of print paste.

• After mixing finally required amount of alkali is added to the dye bath and mix them with the help of stirring.

Screen-printing method:

• The fabric is placed on the printing table of flat screen-printing machine. 
• Then the screen is placed on the sample fabric.
• The printing paste is taken on the screen perforation.
• Thus we can find the printed fabric with a smooth wooden strike the paste is spread over             the screen with slight pressure.
• So that the dye particles can penetrate through the screen perforation.
• Thus we get printed fabric.

Conclusion:

     

     Screen printing with reactive dyes is an effective method for achieving vibrant, durable prints on cotton fabric. This process requires precision in preparation, printing, and post-treatment to ensure optimal results. Understanding and adhering to the protocol enhances the quality and longevity of the printed material.

Precautions:

1. We use deal with chemicals use hand gloves. 

2. Carefully mix all the chemical with water. 

3.Follow safety guidelines for operating the dyeing machine.