“THE STUDY OF SHRINKAGE BEHAVIOR OF RIGID AND STRETCHABLE DENIM FABRICS

APPLYING DIFFERENT WASHING TECHNIQUES”

Nadeem Afraz

Lecturer (Textile Engineering)

Bahauddin Zakariya University College of Textile Engineering, Multan.

Dr. Nabeel Amin

Director/Asst. Professor (Textiles)

Institute of Textile and Industrial Sciences, UMT, Lahore.

3rd International Conference on Textiles and Clothing organized by Institute of Textile & Industrial Sciences,

UMT Lahore

with collaboration of

“Society of dyers & Colorists” and “The Textile Institute, UK”.

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Abstract

The shrinkage margins of garment before washing are set in blanket form, and after washing these shrinkage margins do not meet pre-calculated shrinkage values and ultimately garment “fit to body” out sizes marginally.

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Objectives of Studies

To control the dimension variations of garments

To control the size chart variations

To improve MARKER efficiency.

To reduce rejection rate .

To identify shrinkage changes with respect to the type of fabric.

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The term shrinkage can simply be defined as a

change in the dimensions of a fabric or garment,

there are number of factors that influence fabrics

One major factor is that fabric Shrink because it

under stresses during manufacturing and in

relaxed form while garment washed.

Shrinkage Behavior

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Experiment Design

Fabric Selection:

Denim fabric is manufactured in a number of types but with the view of preciseness we select its major kinds which are in 3/1 Right hand twill (RHT) Rigid and Stretchable with weight range 9 Ozs./yd .

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Shrinkage Test

Shrinkage percentage was calculated in both warp and weft directions by using AATCC test method 135-2004.

Conditioning of Samples:

Temperature: 21oC ± 1oC

Relative humidity: 65% ± 2%

Time: 4 hours before and 4 hours after wash

Two form of denim were used to compare shrinkage:1. Blankets

2. Panels/Leg tubes.

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Stages of Garment Washing Process

Washing Process

Stone wash Enzyme wash Bleach wash

Stage 1 Load of Garment and stones

Load of Garment Load of Garment

Stage 2 Enzymatic Desizing

Enzymatic Desizing

Enzymatic Desizing

Stage 3 Rinse Rinse Rinse

Stage 4 Stone wash Enzyme wash Bleach wash

Stage 5 Rinse Rinse Rinse

Stage 6 Extract Extract Extract

Stage 7 Tumble Dryer Tumble Dryer Tumble Dryer

Stage 8 Unload Unload Unload

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Recipe for Enzyme De-sizing

Name Quantity

Enzyme 50ml (1% on the wt of garment)

Antistain 50ml (1% on the wt of garment)

Wetting Agent 25ml (0.5% on the wt of garment)

De-sizing Procedure

• Liquor Ratio 1:10• Temperature @ 140 °F• Process time 15 minutes• Loading Capacity 120 Kgs• Extraction at 450 RPM.• Rinse time 3 minutes

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Recipe for Stone Wash

Name Quantity

Weight of stone 5kg (Standard weight)

Antistain 25ml (0.5% on the wt of garment)

Chemwet 25ml (0.5% on the wt of garment)

Stone Wash Procedure

• Temperature @ 140 °F• Process time 40 minutes• Rinse time 3 minutes• Loading Capacity 120 Kgs• Extraction at 450 RPM• Rinse time 3 minutes

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Recipe for Enzyme wash

Name Quantity

Valuemax(A326) 50ml

Antistain 25ml (0.5% on the wt of garment)

Chemwet 25ml (0.5% on the wt of garment)

Enzyme Washing Procedure

• Temperature @ 140 °F• Process time 40 minutes• Rinse time 3 minutes• Loading Capacity 120 Kgs• Extraction at 450 RPM

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Recipe for Bleach Wash

Name Quantity

NaOCl 1 liter

Antichlor 500 gm

Bleach Washing Procedure

• Temperature @ 140 °F• Process time 40 minutes• Rinse time 3 minutes• Loading Capacity 120 Kgs• Extraction at 450 RPM• Rinse time 3 minutes

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Warp Shrinkage (Rigid Fabric)

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Weft Shrinkage (Rigid Fabric)

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Warp Shrinkage (Stretchable Fabric)

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Weft Shrinkage (Stretchable Fabric)

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Results and Discussion

In general Shrinkage is greater in Blanket Form than in Panels in all washing techniques.

Enzymatic De-sizing causes minimum Shrinkage in Stretchable fabric either in Blanket or Panel form.

Stretchable fabric shrinks more in weft because Lycra is used in it.

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Recommendations

It is recommended that in denim garment manufacturing the shrinkage should be measured in panel form rather than in blanket form and size chart be made accordingly based on the shrinkage rate occur in panel followed by specific washing technique demanded by customer.

The shrinkage margins may be set in size chart of garment as per required wash and garment will ultimately “fit to size” that will ultimately reduce rejection and alteration rate of the garment unit

Shrinkage margin may be considered in MARKER Making-- that will improve marker efficiency and reduce wastage while calculating fabric for an order.

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Future works

1. Study of construction shrinkage of the denim fabric.

2. Study of processing shrinkage to make formula to calculate shrinkage on each washing technique.

3. Study of performance properties of denim fabric/ garment applying different washing techniques.

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