Theory
Color fastness to washing is the resistance of a material to change in any of its coloring characteristics as a result of washing with detergent. It is very important for fabric and ready-made garments.
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Objectives
- To know about the color fastness to wash.
- To know about the procedure of determining color fastness to wash.
- Learn about the importance of color fastness to washing.
Apparatus
- Scissors
- Sewing machine or stapler
- Weight balancer
- Steel balls
- Greyscale, etc.
Recipe
Calculation
M: L = 1:20
Sample weight = 1.30 gm
So, liquor = (1.30 ✕ 20) = 26 ml
ECE detergent = (4 ✕ 26) / 1000 = 0.026 ml
Sodium perborate = (1 ✕ 26) / 1000 = 0.104 ml
Fresh water needed = {26 - (0.026 + 0.104)} = 25.87 ml
Working Procedure
- Collect dyed sample fabric and multi-fiber fabric as required size and weight, pin-up them, or stitch them together.
- Take chemicals and freshwater as per calculation in dyeing tube.
- Immerse the sample with multifiber fabric in a dye tube and set the temperature at 60℃ for 30 minutes.
- After 30 minutes, compare the sample change and stain with greyscale and determine the color fastness to wash with grading.
Processing Curve
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| Color Fastness Due to Wash Curve ©Textile Pad |
Assessment
Greyscale No 1: Change in shade
Greyscale No 2: Staining
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| Grey Scales ©Textile Pad |
Precautions
- Recipe calculations should be done carefully.
- Weighting of chemicals should be done carefully.
- The amount of water and sample taking should be done accurately.
Conclusion
Colorfastness to wash is very influential for dyed fabric. Using detergent may degrade the coloring quality of fabric if the color fastness is very poor. So, colorfastness to washing quality must be minimum good for a dyed fabric, this will increase the quality of dyed fabric.