Garments Washing: Normal & Silicon wash

Comparative Study on Normal & Silicon Wash

Maruf Mahfuz 

Email: maruf.txt@gmail.com 

Department of textile Engineering

World university of Bangladesh

 Cell no: 01738676060

Introduction

The technology which is used to modify the appearance, outlook comfort ability and fashion of the garments is called garment washing.[1] Depending on garments construction different types of washing process can be done. Twill/Canvas/Knitted/Corduroy - Normal wash, Pigment wash, Caustic, Silicon wash Denim/Jeans/Gabardine - Enzyme wash, Stone wash, Bleach wash, Acid wash Grey fabric- Super white wash.[1]

Objective

Normal wash is required for the following reasons:

• The main aim is to remove starch dust and dirt from the garments.
• Sometimes softening and bringing a used look is also a reason of normal wash.
• For color garments removal of unfixed dyes can also be achieved to improve color fastness.
• In special cases intentional shrinkage in garments can be achieved.
• To remove dust, dirt, oil spot, impurities from the garments.
• To remove size materials from the garments.
• To remove starch presents on the garment fabrics.
• For soft feeling to wear the garments after purchasing.
• To achieve buyer washing standard.

Chemicals required for normal wash

• Detergent
• Desizing agent 
• Wetting auxiliaries
• Acetic acid
• Softener – Polyethelyne3
• Softeners – Silicone

Machineries used for Normal Wash

1. Washing machine

2. Chemical mixture machine

3. Hydro extractor machine

4. Dryer machine

Process flow chart of washing in industry:

Desizing

↓

Required washing

↓

Softening

↓

Hydro extraction

↓

Dryer

↓

Quality control

Process of Normal wash

The Normal/Garment washing process of batch of 70 kg Twill/Canvas Garments are described below:-

First Step:-

• Lot size: -....................... 70 kg Twill/Canvas Garment.
• Add water @ L: R = 1: 8-10 ............560 --700 Liter.
• Machine Running.
• Add detergent @ 0.5 gm. / liter ............ 280-350 gm.
• Temperature..... Sometime cold & sometime 40°c to 60°c.
• Time .............................. 5 to 10 mts.
• Drop the liquor.
• Cold wash.

Second Step:-

• Add water @ L: R = 1: 6 ......... 420 liter.
• Washing machine running
• Add Flax softener @ 0.6 gm. / liter .......... 252 gm.
• Add Acetic Acid @ 0.5 gm. / liter........... 210 gm.
• Time................................... 5 to 10 mts.
• Drop the liquor.
• Unload the Garments on trolley.

Third Step:-

• Hydro extractor machine.
• Hydrocxtraction the garment to remove excess water from the Garment.

Fourth Step:-Steam Dryer / Gas Dryer.

• Load on steam dryer -50 kg
• Temperature -60°c -70°c
• Time -40 -50 mts for dry.
• Time -10 -15 mts for cold dry.

or

• Load on gas dryer -50 kg,
• Running the machine
• Temperature: -70°c -85°c.
• Time: -30 -35 mts for dry.
• Time: -10 -15 mts for cold dry.

Fifth Step:-

After drying it will be quality checking and good quality Garments will be delivery to Garments factory and for further process.

Description

Garments can be inverted to minimize unwanted abrasion streaks (especially useful when preset creases are present). Load machine with garments. Desize with alpha amylase enzyme and detergent. Drain out the liquor. Rinse the substrate. Fill machine with water and heat to 60◦C.The liquor ratio can range from 10:1 to 20:1. A number of synthetic detergents can be used. Also, alkaline products such as soda ash or caustic soda can be added in amounts ranging from 0.5 to 2.0 grams/liter. Some chemical suppliers offer special products that accelerate the wash down process, dependent upon the particular dyestuff used. Wash/tumble action for 20-60 minutes, depending upon desired effect. Drain out the liquor and rinse. Apply softener. Tumble dry. Invert garments, if previously turned. Press, if required & then send it to the quality control section for checking.

Precaution

• Precautions are required to be taken for unwanted shrinkage issue and back staining
• Flax softener (cationic or nonionic) diluted with hot water then use in the machine[3].

After treatment:  

Softeners: [5]

The application of softeners at the end of the dye cycle improves the appearance, hand, and ease of pressing of the dyed garments after tumble drying. Durable press appearance ratings for 100% cotton woven garments after garment dyeing and tumble drying are usually around 1.0-1.5. The addition of a polyethylene softener in the final bath after dyeing generally increases this rating to 1.5-2.0. Use of a softener formulation with 2% polyethylene and 2% amino-functional silicone in the final rinse bath typically results in appearance ratings of 2.0-2.5, and ratings as high as 3.0 have been achieved for knit garments. As with all cationic softener systems, yellowing during drying may be a problem, and care must be taken to avoid unacceptable shade changes on white and pastel shades.

Figure: Atomic Structure of silicon

Treated with silicon softener

Silicone softeners have a firm place in final finishing for a very important reason. A piece of fabric which has been subjected to pretreatment ,dyeing and fixing processes is almost impossible to be appealing to any one without taking a corrective measures of handle[3]. 

Figure: General Structure of a silicone softener.

The Application of silicone softeners turns hard and a brittle fabric into a soft pleasant textile with which the buyer can expect a high degree of wearing comfort.
Silicone have wide spread applications in the textile industry from fiber, yarn and fabric production to final product finishing.Thier distinctive chemistry imparts a range of characteristics. A variety of silicon etechnologies  have application in the textile industry.

They include: 

•  Polydimethylsiloxanes.
•  Amido, Amino Functional Silicones.
•  Methyl Hydrogen Silicones.
•  Epoxy Functional Silicones.
•  Hydroxy functional Silicones.
•  Silicone Polyethers
•  Epoxy Polyether Silicones.

Figure: Working properties of silicon [4] 

Process:

The product, prediluted in a small quantity of water, is added to the rinse bath following the enzyme fading process at approximately 1.5-2.5 gms per liter (2.5-4% over weight of garments). Softener can also be used in the same bath as the enzyme fading process, depending on the level of back-staining desired. The product is to be added 30 minutes after the start of the enzyme fading process. The pre-diluted product is added in the same bath and treatment is continued for another 15-20 minutes. This does not inhibit the fading process and the processed denim garment has the same appearance and feel as that resultingbfrom the traditional pr cess In addition to its use in denim garment processing Softener can be used to process twill garments where a faded or washed look is typically achieved using cellulose enzymes. In this case Softener can be used in the rinse bath following the biopolish process or in the same bath as the enzyme bath. The twill garment will have a washed look and a soft hand.

Conclusion:

The purpose of washing laundry is to loosen dirt from the textile fibres and to rinse it off by using water as solvent. Depending on the laundry type and the degree of soiling, professional washing machines often provide a large number of different either adjustable or pre-defined washing programs. They vary e.g. in terms of using pre-washing, the number of rinsing cycles, the temperature or the program duration. All of the parameters should follow carefully to get fruitful result after washing shown by the garments, otherwise it will be difficult to the succeeding process like as softening finishing & ironing.

References

1. http://garmentec.blogspot.com

1. http://textilecollection.blogspot.com/2012/02/normal-washpigment-washcaustic-wash.html

3. http://seydel.com

4..http://www.google.com.bd/search?q=SILICONE+CHEMISTRY+FOR+FABRIC+CARE

5.www.dowcorning.com/ecosoftener