Bleach Washing Process:
Bleach wash is one of the precise garment washing techniques that is used to fade a higher degree of color. We can define bleach wash in the following way, the wash which is done to cut more color and bring light shade on denim garments is called bleach wash. Bleach washing is normally carried out with a strong oxidative bleaching agent such as sodium hypochlorite (NaOCl) or potassium permanganate (KMnO4). Bleach washing may be carried out with or without the addition of stone. The bleach washing effect and discoloration usually depend on strength of the bleach liquor, liquor quantity, temperature and treatment time. The bleached fabric materials should be properly antichlored or after washed with peroxide to reduce the subsequent yellowing or tendering of the bleached denim fabric. By applying bleach washing special type of fading effect can be produced in the garments. Bleach wash can be applied on all types of garments such as woven, knit, etc.
Objects of Bleach Washing:
- To remove the size material from the garments.
- To remove the starch present on the garments.
- For soft feeling to wear the garments.
- To increase the color fastness and rubbing fastness.
- Especially develop the “Bio-polishing’’ affect cotton/Denim.
- Enzyme improves the anti-pilling properties.
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Process Flowchart of Bleach Washing:
The basic steps of denim bleach washing are as follows:
Garment loading with or without stone
Desizing (10–15 min, at 55–60°C)
Addition of enzyme, acetic acid, anti-back staining agent (15 min)
Rinsing (2-3 min)
Bleaching (15–30 min)
Working Procedure of Bleach Washing:
First, the fabrics were cut in appropriate shape before and put that on the bath. The machine had to clean so that the chemicals that remained on the machine from the previous bath can be washed out. The chemicals ratio that required for the number of fabrics was calculated that are going to put on the bath. Then the fabrics put on the bath and start desizing it for 10min with the required chemicals. After desizing, bought out the fabrics from the machine and rinse washed the fabrics. Again the fabrics put on the bath with the addition of enzyme, acetic acid, anti-back staining agent and ran the machine for 15min. After that again rinse washed the fabrics for 2-3min. The fabrics put on the bath again with the addition of KCI bleach and ran the bath at 3 different times for getting 3 shades. Then bought out the fabrics from the bath and put that on the hydro-extractor machine for absorbing the excess water from the machine. After that, the fabrics put on the drying machine at 80˚C to dry the fabrics.
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Advantages of Bleach Washing:
- Can produce special effect on garments.
- Enhance the beauty of garments.
- Can attract the buyers easily.
- Huge demand to the young generation
Limitations of Bleach Washing:
- The same level of bleaching is very difficult to achieve in repeated runs.
- Bleaching treatment sometimes damages cellulose, resulting in strength loss and or pinholes at the seam, pocket, etc.
- Bleaching liquor is harmful to human health.
- This may also cause corrosion to machine parts.
- Bleaching treatment needs antichlor treatment to eliminate the subsequent yellowness in the fabric.
- Chlorinated substances occur as abundant products in bleaching, and pass into the effluent where they cause severe environmental pollution.
You may also like:
- Performance Analysis of Denim Garments by Bleach Wash
- Stone Washing Process of Denim Fabric
- Effect of Enzyme Wash on Denim Garments
- Enzyme Stone Wash Process of Garments
- Denim Enzyme Wash Process
- Ozone Fading Techniques for Denim Finishing
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.