Cotton is a soft, fluffy staple fiber. It is a natural and most popular fiber. Cotton is dyed with a range of dye types, including vat dyes, and modern synthetic reactive and direct dyes. The flow chart of cotton dyeing process of cotton is given below.
Flow Chart of Cotton Dyeing Process
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The fabric was loaded and run for 5-10 minutes at normal temperature
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BOS, FE,CF,H-53 (Scouring Chemicals) were added at a time for 5 minutes
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Caustic was added at normal temperature for 5 minutes
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The temperature increased to 60 ºC
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Hydrogen per Oxide(H2O2)was added for 5 minutes
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The temperature increased at 95 ºC and continue for 1 hrs
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Sample check
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Cold wash at 40 ºC for 5-10 minutes
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Hot wash at 95 ºC for 5-10 minutes
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The required amount of water was loaded
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Acetic acid was added
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The temperature increased at 80 ºC for 15-20 minutes
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Cold wash at 40 ºC and drain
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Water filled and Acetic acid was added
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PH check at 4.5
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Leveling agent at 60 ºC for 5-10 minutes
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Salt at 60 ºC for 5-10 minutes
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Run time 10 minutes
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Dyes at 60 ºC for 30 minutes
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Run time 10 minutes
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Check the sample
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Soda ash at 60 ºC for 40 minutes
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Run time 10 minute
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check the sample
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Colour steam
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B D (Bathe Drain)
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Wash
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Hot wash
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Acetic Acid
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Run for 20 min
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Then unload the garments
Dyes are used for coloring yarns and fabrics. Dyes are molecules is absorb and reflect light at specific wavelengths to give human eyes a sense of color. Basically, there are two major types of dyes. one is natural and another is synthetic dyes. The natural dyes are extracted from natural substances such as plants, animals, or minerals. Synthetic dyes are made in a laboratory. Chemicals are synthesized for making synthetic dyes. Some of the synthetic dyes contain metals too. In the garments industry, the artificial dye used most.
Author of this Article: Rana Sohel Executive Engineer Sunman Textile Mills Ltd. Chittagong Cell: +8801912-420118 Email: [email protected]