TÀI LIỆU TIẾNG ANH VỀ WASH VẢI DENIM NGÀNH MAY - DENIM WASHING

CRUSHED DENIM Textured effect achieved through a special fabric construction coupled with wet processing, Fabric is woven with an over twist weft yarn, The effect can also be improved b

DENIM WASHING

Abinash Mohanty Anurag Singh

Avinash Kumar DFT-4

INTRODUCTION OF DENIM…

• Denim is a rugged

cotton twill textile, in

which the weft passes

under two or more

warp fibres, producing

the familiar diagonal

ribbing identifiable on

the reverse of the

fabric

Types of Denim

1 BUBBLE GUM DENIM (Lycra containing denim that has between 35 to

50% stretch)

2 COLOURED DENIM (fabric is woven with dyed yarn either warp or weft, It

can also be obtained by Piece dyeing process.)

3 CRUSHED DENIM (Textured effect achieved through a special fabric

construction coupled with wet processing, Fabric is woven with an over twist weft yarn, The effect can also be improved by bleach and stone )

4 DENIM FROM FOX FIBRE (Denim fabric manufactured by coloured

cotton fibre that grows naturally developed and patented by California cotton

breeder Sally Fox NITRA, India has also done work on this line.)

5 MARBEL DENIM (It is an another name for acid wash, Some crushed denims, if strongly bleached, are also called marble.)

6 ECRU DENIM (The denim, which is not having dyed yarn i.e only grey yarn in warp & weft.)

7 REVERSE DENIM (Where the face side and reverse side look alike.)

8 VINTAGE DENIM (A denim treatment that applies heavy stone washing or a cellulose enzyme wash with or without bleach for an old and worn outlook.)

BUBBLE GUM DENIM REVERSE DENIM

COLOUR DENIM

DENIM WASHING

• In denims, garment washing is done to produce

effects like color fading with or without patchiness, crinkles, seam puckering, hairiness, de-pilling,

softened-hand feel, stabilized dimensions etc.

• Denim washing is the aesthetic finish given to the denim fabric to enhance the appeal and to provide strength

• Denim washing is known

as one of the finishing

treatment that has vast

usage because of creating special appearance and

updating clothes.

• There is different methods

of denim washing.

Types of Denim Washing…

Denim washing are of two types.

Other mechanical washes-

LASER TECHNOLOGY

SUPER STONEWASH

Scrubbing

Laser technology

Scrubbing

Tagging on pockets

RINSE WASH

Ozone fading

Over dye- tinting

Sun washing

Quick wash denim

Water jet fading

Vintage etc.

OTHER CHEMICAL WASHES

Stone Washing

• This method is most common and is used to give

denim an 'old-look'

• Pumice stone is one of the most important

components used to abrade the surface of the

fabric to obtain a surface pattern effect with color

contrast and soft - handle

• In this process, the fibres

on the surface of the

fabric are broken and

removed and the inner

white fibres of the warp yarn are gradually

exposed.

• Natural patterns can be

formed as the degree of abrasions varies in various parts of the garment.

Selection of Stone

• According to the end product & effect required.

• Large, hard stones last longer and may be suited

for heavy weight fabrics only.

• Smaller, softer stones would be used for light

weight fabrics and more delicate items.

• Stone wt /fabric wt = 0.5 to 3 /1

Recommended Specification for

when exceed 10% they

increase apparent density

1 gm/cm3, the stone will

not float in water during

process

Stone Wash Cycle

• Loading of denim garment and stones

• Desizing for about 15 minutes- Detergent plus enzymes

Limitations

• Outcome of a load of jeans is never uniform.

• Damage to wash machineries and garment due to stone to machine abrasion.

• Increase in labor to remove stone particles from finished garments.

• Water pollution during disposal of used liquor.

- Flat surfaces (tables, ironing boards)

- On the dummy (inflatable dummies,

sometimes standing, sometimes flat, sometimes 'seated')

- Various templates can be used to create a

3D effect

Used in Various Ways

SAND BLASTING

• This technique is based on blasting an

abrasive material (mostly sand) in

granular, powdered or other form

through a nozzle.

• It is purely mechanical process.

• It is a water free process.

• Variety of distressed or abraded looks

possible.

chemically coated with an abrasive

HAND SANDING or HAND BRUSHING

• Use of sandpaper to

abrade surface.

• Variety of looks and

designs can be created

Denim bleaching

• In this process, a strong oxidative

bleaching agent such as sodium

hypochlorite or KMnO4 is added

during the washing with or

without stone addition

• Discoloration is usually more

apparent depending on the

strength of the bleach liquor

quantity, temperature and

treatment time

• Proper after wash or

anti-chloring (incase of sodium

hypochlorite bleaching agent)

of bleached denim to

minimize subsequent

yellowing and tendering of denim

Process Cycle of Denim Bleaching

Enzyme Washing

• This is a bio-catalytic

method where in an

ultra-soft handle effect can be

produced on denim

• The hydrolytic effect of

enzymes causes the loss of surface fibre, which

improves surface

smoothness and softness of the fabric.

• Cellulase enzymes are natural

proteins, which are used in

denim garment processing to

get stone wash look on to the

denim garments without

using stones or by reducing

the use of pumice stone

• Cellulase attacks primarily on the surface of

the cellulose fibre, leaving the interior of the fibre as it is, by removing the indigo present in the surface layer of fibre.

ENZYME WASH CYCLE

• Loading of denim Garments (addition of Stones is optional)

• Desizing with- alpha-amylase Enzyme, or- Oxidative desize

• Rinsing

• Adjusting pH to 4.5 to 5.0 with- acetic acid, or- buffer system

• Heating to 50 to 60 C

• Addition of cellulose enzyme

• Tumbling for 30 to 60 minutes

• Hot rinsing at > 65 C

• Cold washing

• Softening

• Dry tumbling

Advantages

• Prevents tendency of pilling after relatively short

period of wear

• Can be applied on cellulose and its blend

• Fancy colour-flenced surface can be obtained without

or a partial use of stone.

• Less wear & tear of machinery

• Most economical due to more water

• Garment load size of the machine is limited.

• Post treatment required.

Acid Wash

• Acid wash can be

carried on Indigo &

Sulphur base fabric

garments

• Acid wash is a chemical

wash on denim which

stripped the top layer of

color and make a white

surface while the color

remained in the lower

layers of the material,

giving it a faded look

• This wash is being carried out by pre soaking stones in bleach and then followed by neutralization.

• Acid wash of denim garment

normally carried out by

tumbling the garments with

pumice stones presoaked in a

solution which contains sodium

hypochlorite (5 to 10%) or

potassium permanganate (3 to

6%)

• The process is achieved by soaking

pumice stones in chlorine and letting

these stones create contrast

In this wash addition of water is not required The color contrast can be increased by optical brightening treatment.

Acid Wash Garments

ACID WASH CYCLE

• Loading of garment With pumice tones

• Desizing for about 10 to 15 minutes

• Drying

• Dry tumbling for 10 to 30 minutes

• Cooling without Addition of water

• Per-oxide wash

• Optical Brightening

• Softening Treatment

• Acid washed, indigo dyed denim has a tendency to yellow

after wet processing

• The major cause is residual manganese due to incomplete

neutralization, washing or rinsing

Remedy:

• Manganese is effectively removed during laundering with addition of ethelene-diamine-tetra-acetic acid as chelating agent

• Acid washing jeans avoided some of problems of stone wash, but came with added dangers, expenses, and pollution

Acid Wash – Limitations & Remedies

1 www.fibre2fashion.com

2 Denim garment washing process-ATIRA

3 Denim garment processing –Express Textile(march 2003)

4 Garment washing & finishing- Pearl Academy of

Fashion

5 www.textileworld.com

6 www.textileschool.com

THANK YOU