Understanding About Blend Dyeing Process
Shareful Islam Palash
Lecturer, Institute of Textile Engineering & Information Technology
Blends are any textile material from fiber through yarn to fabric which are deliberate combination of chemically or physically different fibrous polymer. The term ‘blending’ is used by the yarn manufacturer to describe specifically the sequence of processes required to convert two or more kinds of staple fibers into a single yarn composed of an intimate mixture of the component fibers. Cotton and Polyester blend is an example of chemically different blend and Cotton and Viscose is physically different blend because both are cellulosic. Polyester cotton blend dyeing is popular in dyeing industry. Polyester/cotton blends are dyed mainly by two dyeing bath methods using appropriate dyes and chemical auxiliaries. This dyeing method is relatively long and complex. Polyester and cotton are dyed under completely different parameters. Cotton is dyed by employing alkaline conditions at 60ºC or 80°C and using reactive, direct or vat dyes whereas polyester is dyed using disperse dyes in an acidic medium at 120°C or 130ºC.
Object of Blending/Blend Dyeing:
- Dilution of an expensive, lusterious fiber by blending with cheaper substitute.
- To incorporate of more durable component to extend the useful life .e.g. core spun yarn.
- A compromise to take advantage of desirable performance characteristics, contribute by both fiber component .e.g. P/C blend to get comfort of cotton, strength and crease recovery of polyester.
- The development of novel fabric design for garments incorporating multicolored effect. e.g. polyester part is dyed and cotton part undyed.
- The presence of attractive appearance using by combination of yarn of different luster, crimp is possible by blending.
- Colourant modification is possible by blending.
- Finishing process modification.
- Improved moisture absorption.
- Reduce anstistatic characteristics pilling.
Process Sequence of Polyester/Cotton (P/C) Blend Dyeing:
Dyeing P/C Blend with Disperse and Vat Dye:
- Disperse dye ————————-X%
- Vat dye——————————–Y%
- Dispersing agent——————–o.5-1%
- Wetting agent————————0.5-1%
- pH————————————4-5 with acetic acid (30%)
Prepare the bath with dispersing agent, wetting agent and acetic acid. Treatment for 10-15 minute at 50-60oC. Then add disperse and vat dye in the bath. Dyeing for 10-15 minute. Raise temp. Up to 130oC in 60-90 minute. After PET part dyeing cool to 80oC for proper levelling then add caustic and hydrose and dyeing 15 minute. Cooling to 60oC and dyeing for 30 minute for better exhaustion. Rinse with cold water and oxidation with hydrogen per oxide for 15 minute at 50oC. Then rinsing with cold water and soaping 95oC for 25 minute using 2g/l lissapol. Hot and cold rinse and then final wash off.
Dyeing P/C blend with Disperse and Reactive Dye (Thermosol Process):
- Disperse dye —————————-X%
- Reactive dye —————————-Y%
- Soda ash———————————5-20g/l
- Migration inhibitor ———————10-20g/l
- Wetting agent—————————1-2g/l
Blend Dyeing Procedure:
Padding with disperse and reactive dye at 20-30oC. Liquor pick up 60-80%.
Partial drying is done to avoid migration of dyes. Here keep m.c 25%.
Complete and even dyeing at 110-150oC.
It’s done at 180-220oC about 30-45 sec. to fixation dye.Polyester dyeing complete here
Padding at 20-30oC. Pick up 50-60%. Caustic and salt used for Procion mx and Procion H.
Steaming is done 103-105oC about 30 sec. for procion mx and 45-75 sec. for procion H.
A typical 8 box wash off is given by Cold, hot water and detergent.
- Box-1:———————-water 60oC.
- Box-2&3:——————-Detergent 5 gm/l at boil
- Box-4&5:——————-water at the boil
- Box-7:———————–water 60oC.
- Box-8:———————–Cold water.
By this process blended dyeing is complete.
You may also like:
- Dyeing of Polyester Cotton Blended Fabric in Single Bath
- Polyester/Cotton (P/C) Blends Fabric Dyeing: Recipe, Parameters, Flowchart and Dyeing Curve
- Blending of Cotton-Polyester Fibre to Produce PC / CVC Yarn
- Dyeing of Cotton / Polyester Blended Knit Fabric with Reactive / Disperse Dyes Using Jet Dyeing
Founder & Editor of Textile Learner. He is a Textile Consultant, Blogger & Entrepreneur. He is working as a textile consultant in several local and international companies. He is also a contributor of Wikipedia.