Bleach Wash of Woven Denims: Analysis of before and after Wash Properties (Part-6)

Bleach Wash of Woven Denims: Analysis of before and after Wash Properties (Part-6)
S.M. Bappy Rana
Dept. of Textile Engineering
Bangladesh University of Business & Technology
Cell: +8801781630519

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3.13 Shrinkage test:
Shrinkage is the process in which a fabric becomes smaller than its original size, usually through the process of laundry. Cotton fabric suffers from two main disadvantages of shrinking and creasing during subsequent washing.

There are two types of shrinkage occurs during washing.
  1. Length wise
  2. Width wise
3.13.1 Working procedure:
  1. For Shrinkage test Fabric sample is marked 8"*8" with square.
  2. Then Sample is washed with bleaching powder 10, 15 and 30 minute. And dried in dryer machine.
  3. Then the shrinkage is measured of the sample.
3.13.2 Apparatus:
  • Denim Apparels
3.14 Count Measurement:

3.14.1 Apparatus:
  1. Bessley balance
  2. Template
  3. Dead weight
3.14.2 Working procedure:
  1. For count measurement warp and weft way yarn is collected from before washed and after washed (10, 15, 30 minute) sample.
  2. Then the yarn count is measured by Beasley’s balance.
3.14.3 Count measurement test is done by Beasley’s balance of Bangladesh University of business and technology (BUBT).
Beasley’s Balance
Figure: Beasley’s Balance
3.15 EPI & PPI measurement:

3. 15.1 Apparatus:
  1. Counting glass,
  2. Needle.
3.15.2 Working procedure of EPI & PPI measurement:
  1. For measuring EPI & PPI measurement the fabric sample - Before washed & after washed (10, 15, 30 minute) is taken.
  2. Then the EPI & PPI is measured by counting glass.
3. 15.3 EPI & PPI measurement test is done by Counting glass from Bangladesh University of business and technology (BUBT).
Counting glass
Figure: Counting glass
3.16 Comparison of color depth variation:

  1. Color Controller machine
  2. Grey Scale
  3. Denim fabric ( Before Wash & After Wash Sample)
3.16.2 Working Procedure:
  1. To compare of shade variation we take the before and after wash sample.
  2. Shade variation is notified by the color controller machine.
  3. We note down the result which is notified by grey scale.
3.16.3 Color depth comparison is done by color controller machine from Bangladesh University of business and technology (BUBT).
Color controller machine
Figure: Color controller machine
3.16.4 Snap shot of bleach washed denim:
bleach washing treatment
Figure: Color depth comparison after bleach washing treatment
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Mazharul Islam Kiron is a textile consultant and researcher on online business promotion. He is working with one European textile machinery company as a country agent. He is also a contributor of Wikipedia.

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