Yarn dyeing is slightly difference from woven or knit dyeing. Yarns are dyed in package form or hank form by yarn dyeing process. Flow Chart of Isothermal Yarn Dyeing Process
Following the dyeing process are followed in the yarn dyeing section:
- Isothermal Process
- Migration PrTurquoiserquise Process
- Span & Non-spun Polyester Process
- PC, CVC Process
- Viscose Process
In this article, I will give a flowchart of yarn dyeing in the isothermal process.
Flow Chart of Isothermal Process in Yarn Dyeing: From pretreatment to finishing,
Yarn is wetted fairly with 90% water
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Chemicals are injected for 2 cycles 10-12 min at 40-500 ºC
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Chemical (Chintex NF -150, Jinsofter BSK/CBF , Ablutex-AP-750 (42% Soln, Reduzin AC-BL-100 ) Dozing at 50 0C With Hold time 2 min & then Run for 4 min
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NaOH is injected for 5-6 min at 500 ºC& the Run for 6 min.
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Temperature is raised to 600 ºC & then H2O2 (50% Soln) is injected at 600 ºC for 6 minute
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Run time 1000º C ×48 min.
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Cooling at 750 ºC
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Hot Drain
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Water filling for 6 min & then Overflow is done for 2 cycle (12min) for cooling
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Hot wash is done at 800 ºC for 2 cycle (12min)
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Drain
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90% water filling again overflow is done for 12 min
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Peroxide Killer (Reduzol – PK) is Injected at 600 ºC & run for 14 min
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Drain
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Overflow is done for 6 min to cool the temperature
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Drain
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Water filling & overflow is done for 10 minute
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Acetic Acid is added at normal temperature (36-400 ºC)
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Run for 11 min
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Water filling & overflow is done for 10 minute
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Drain
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Bleaching Test (Immersion test)
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90% water filling
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Chemicals {Jinlev-RLA-225 + Hostapol –EH Liq + Antisil –Conz + MA Scour Ain (Prep-IN) }are mixed in the mixing tank & ½ of the chemicals are injected & run for 6 min at 400C
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Color is mixed at 400 ºC with the rest of the chemicals & then dosing for 30 minute
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Run for 12 min
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Salt is mixed with return water in the tank
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Salt dosing is done at 600 ºC & run for 22 min
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Soda dosing is done at 600 ºC & run for 30 min
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Run for 600 ºC × 60 min
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Sample check
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If Ok than Drain
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Water filling
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Overflow for 12 min
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Acetic Acid is added at 400 ºC for 1 cycle
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Overflow is done for 6-7 minute.
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Cottoblanc-NSR +Cottoblanc-SEL is given at 980ºC & run for 30 min to remove unfix colour
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Sample Check
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If OK than drain
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Overflow for 10 min
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Hot wash is done at 600C & Run for 11 min
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Drain for 5 min
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Overflow for 10 min
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Drain for 5 min
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Water filling at 36-400 ºC
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Run for 500C×20 min
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Overflow for 10 min
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Drain
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Water Leveling
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Ablusoft –AC + Oiling –CT -200 + Acetic Acid is added &run for 18 min at 600 ºC
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Unload
Author of This Article: Rana Sohel Executive Engineer Sunman Textile Mills Ltd. Chittagong Cell: +8801912-420118 Email: rsohel07tex@gmail.com