TEXTILE FINISHING

INTRODUCTION

Dyeing and printing is not the ultimate steps

Something is required to make the fabric more suitable for end-use

Quality of the fabric in terms of appearance, handle, functionally enhanced by some physical means or by chemicals

Therefore, ultimate value addition is done to the fabric by finishing

WHAT IS FINISHING ??????

Finishing is a final process given to a textile material toGive a good appearanceDesirable feel Impart certain durable properties

StiffnessSoftnessWash and wear finishWater repelling finishFire proof finish etc.

To impart some desired functional properties

CLASSIFICATION OF FINISHING

Classification according to the nature of finish

According to the nature of Finish

Physical or Mechanical Finish1) Calendering2) Sanforizing etc.

Chemical Finish1) Mercerization2) Easy care finish etc.

Physical or Mechanical Finish Mechanical / Physical finishes involve specific

physical treatment to a fabric surface to cause a change in the fabric appearance

Also known as dry finish Compacting (Shrinkproofing) Calendaring Raising (Napping, Sueding) Shearing Polishing Corduroy Cutting Decating

Chemical Finish Chemicals are used followed by curing or drying Also known as wet finish

CLASSIFICATION OF FINISHING

Classification according to degree of permanence

According to degree of permanence

Permanent Finish

Temporary Finish

Durable Finish

Semi - Durable Finish

DEFINITIONS

Permanent Finish: Usually involve a chemical change in fibre structure and do not change or alter through out the life of the fabric

Durable finish: Usually last through the life of the article, but effectiveness becomes diminished after each cleaning; and near the end of the normal use life of the article, the finish is nearly removed

Semi-durable finish: Last through several laundering or drycleanings and many are renewable in home laundering or drycleaning

Temporary finish: Are removed or substantially diminished the first time the article is laundered or drycleaned

CLASSIFICATION OF FINISHING

Classification according to performance

According to Performance

Aesthetic Finish– Improved / Altered Appearance 1. Calendering2. Fulling3. Mercerization4. Napping and sueding5. Plisse6. Shearing

Functional Finish– Improved / Altered Performance1. Antiseptic2. Antistatic3. Crease resistant4. Durable press5. Flame resistant6. Mothproofed7. Shrinkage control8. Soil release9. Water and stain repellent10.Waterproof

Aesthetic Finish These finishes modify the appearance and / or

hand or drape of fabrics

Functional Finish These finishes improve the performance

properties of fabrics

AESTHETIC FINISHES Aesthetic Finishes modify the appearance

and /or hand or drape of the fabrics.

Fulling Mercerization Napping And Sueding Plisse Shearing Softening Stiffening

FUNCTIONAL FINISHES Functional Finishes improve the performance

properties of the fabric ; like durability, strength etc.

Antimicrobial/Antiseptic Antistatic Crease resistant Durable Press Flame Resistant Mothproof Shrinkage Control Soil Release Water Proof/Repellant

WOOL FINISHING ROOT

COTTON FINISHING ROUTE

SILK FINISHING ROOT

SYNTHETIC FIBRE FINISHING ROOT

COMPACTING - SHRINKPROOFING

COMPACTING - SHRINKPROOFING

Controlled residual shrinkage is an important quality parameter for manyfabrics. For example, excessive shrinkage is undesirable for fabrics to be made intogarments.

Here, the residual shrinkage should be less than 2% otherwise the garment will not fit after it is laundered.

WHY FABRICS SHRINK ???

Crimp Thickness of yarn Stretching Tension.

SANFORIZER Mechanical compacting is one method of reducing residual

shrinkage. The process forces yarns closer together and the fabric becomes thicker and heavier. As a result of this, the net yardage yield is reduced.

A Sanforizer is a fabric compactor developed by Cluett Peabody. The term Sanforized, is their registered trademark and is used to market fabrics that meet certain shrinkage specifications. The term Sanforized is now generally accepted to mean a fabric that has low residual shrinkage and the term Sanforizing is used to describe shrinkproofing processes.

The process, consists of arange where the fabric is first moistened with steam, to make it more pliable, run through a short tenter frame (pup tenter) to straighten and smooth out wrinkles,through the compressive shrinkage head and then through a Palmer drying unit to set the fabric.

FABRIC SAMPLE

SANFORIZING RANGE

COMPACTOR HEAD

The key to any compactor is the head where force is applied to move parallel yarns closer together. More fabric must be fed in than is taken off.

A Sanforizer uses a thick rubber blanket running against a steam heated cylinder as the compacting force. The thick rubber blanket first goes over a smaller diameter roll which stretches the convex surface of the blanket.

Fabric is metered onto the stretched blanket and the fabric and blanket together come in contact with the steam heated cylinder. At this point, the stretched rubber surface contracts to its original length and then is forced to contract an additional amount as it forms the concave configuration of the heated drum.

Since the fabric is not elastic, an extra length of fabric is thrust between the rubber blanket and the heated cylinder. Friction between the rubber blanket and steel drum force adjacent yarns to move closer together until the unit length of fabric become equal to the unit length of rubber blanket it rests on.

Heat is created by constantly stretching and relaxing the rubber blanket. The blanket is cooled by spraying water on it after the fabric exits from the unit..

COMPACTER HEAD

The degree of shrinkage can be controlled by the thickness of the blanket. The thicker the blanket, the greater is the stretched length at the bend. A longer length of fabric will be fed into the compactor causing the degree of compacting to be greater.

To be effective, the degree of compacting needed should be predetermined ahead of time. This is done by characterizing the shrinking behavior of the fabric by laundering. The degree of compacting should not exceed the degree of shrinking otherwise over-compacting will cause the fabric to "grow" when relaxed. This is as much a disadvantage as is shrinkage.

DECATING

This process is mainly carried out on wool by exploiting its elastic properties in hot and wet conditions by the direct action of the steam on the fabric.

1) dimensional stability; 2) setting of pile after raising; 3) reduction of possible glazing effect after

calendering, thank to the swelling caused by steam blown on fibres;

4) modification of the hand, which is much more consistent after the treatment;

5) pre-stabilisation to autoclave dyeing

SEMI-DECATING Semi-decating is a bach process requiring three steps:

1. winding the fabric onto a perforated cylinder between a cotton decating apron,

2. steaming and followed by cooling the fabric 3. unwinding and batching the finished fabric.

The fabric be wound onto a perforated drum between the interleaving cotton decating apron to form a reasonably thick roll.

Steam is forced through the roll (inside - out) for several minutes to provide moisture and heat.

Compressed air is then blown through the roll in much the same manner as the steam to remove some of the moisture and cool down the fabric. To insure that the effect is uniform from the inside to the outside of the roll, the fabric and blanket are rewound onto another perforated drum so that the outside layers become the inside layers and the cycle is repeated.

At the end of the cycle, the fabric and blanket are separated and wound into individual rolls.

CONTINUOUS DECATING

WATER REPELLENT FINISHWATER PROOF FINISH

WATER REPELLENT FINISH

Water repellent are chemical finish Resist the penetration of water into or

through the fabric Permits the passage of moisture or air

through the fabric Methods

The yarns are coated with water repellent material like wax

The water repellent do not permit the water drop to spread and penetrate

Could be of durable and non-durable types

Non-durable repellents are easily removed in laundering or drycleaning

Non-durable repellents do not provide satisfactory resistance to oily liquids

Durable repellent finish can be either repellent to water or oil or both

Flurocarbon compounds have excellent durability to both drycleaning and laundering

WATER PROOF FINISH

A water-proof fabric, unlike a water repellent fabric, is completely moisture proofed

The fabric is coated or laminated with a film of natural or synthetic rubber or plastic, such as vinyl or polyurethane

Water proof fabrics are not necessarily more desirable than water-repellent fabrics

Water proof fabrics are uncomfortable

Water proof fabric possesses a rather firm, non-rapable hand

PARAFFIN WAXES The oldest and most economical way to make a fabric water

repellent is to coat it with paraffin wax. Solvent solutions, molten coatings and wax emulsions are ways of applying wax to fabrics. Of these, wax emulsions are the most convenient products for finishing fabrics. An important consideration in making water repellent wax emulsion is that the emulsifying system not detract from the hydrophobic character of paraffin. Either non-rewetting emulsifiers or some means of deactivating the hydrophilic group after the fabric is impregnated with the finish must be used.

Paraffin wax melts and wicks into the fabric when the fabric is heated. This will cause most of the fibers to be covered with a thin layer of wax, especially those that are exposed to water, and the fabric will have excellent water repellent properties. The major disadvantage of wax water repellents is poor durability. Wax is easily abraded by mechanical action and wax dissolves in dry cleaning fluids. It is also removed by laundry processes.

WAX EMULSION COMPOSITION

A typical wax emulsion consists of paraffin wax as the hydrophobe, an emulsifying agent, an emulsion stabilizer (protective colloid) and an aluminum or zirconium salt to deactivate the emulsifying agent when the fabric is heated.

SILICONE WATER REPELLENT

Resinous polysiloxanes, Are more resistant to abrasion and less

soluble in dry-cleaning fluids or laundry products.

Aqueous pH is maintained between pH 3-4, stable emulsions can be prepared. When these emulsions are applied to a fabric with a tin catalyst (e.g. dibutyltin-dilaurate), the Si-H group hydrolyzes and condenses to a three-dimensional resinous polymer, making the fabric highly water repellent.

APPLICATION TO FABRICS

Silicone finishes are applied to fabrics either from an organic solvent or from water as an emulsion. When cationic emulsifiers are used to make an emulsion, the finish may be applied by exhaustion since the negative fiber surface charges attract positively charged particles. Generally however, silicone water repellents are co applied with a durable press finish. Durable press resins enhance the durability of the water-repellent finish.

Silicone repellents are also used to make upholstered furniture stain repellent. Chlorinated solvent solutions are sprayed onto upholstery by the retailer as a customer option. The fabric is resistant to water borne stains such as coffee and soft drinks.

FLUOROCHEMICAL REPELLENTS

Fluorochemical repellents are unique in that they confer both oil and water repellency to fabrics.

The ability of fluorochemicals to repel oils is related to their low surface energy which depends on the structure of the fluorocarbon segment, the nonfluorinated segment of the molecule, the orientation of the fluorocarbon tail and the distribution and amount of fluorocarbon on fibers.

Commercial fluorochemical repellents are fluorine-containing vinyl or acrylic polymers. This is a convenient method of affixing perfluoro side chains to fiber surfaces that can orient air-ward and give a reasonably close packed surface of -CF2- and -CF3 groups.

RECIPE

A typical formulation for polyester-cotton rainwear and outerwear is given.

The finish is applied by padding the formulation onto fabric, drying at 120°C and curing 1-3 minutes at 150-182o C.

The fabric will give a 100 spray rating initially and an 80 rating after 5 home laundering-tumble drying cycles. An 80 spray rating is expected after one dry cleaning cycle.

In addition, oil repellency rating of 5 initially and 4 after laundering or dry cleaning is expected.

SPRAY TEST

100 - No sticking on wetting of upper surface 90 - Slight random sticking or wetting of upper surface 80 - Wetting of upper surface at spray points 70 - Partial wetting of whole of upper surface 50 - Complete wetting of whole of upper surface 0 - Complete wetting of whole upper and lower surface

FLAME RETARDANT FINISH

FLAME RETARDANT FINISH

When solid materials are heated, physical and chemical changes occur at specific temperatures depending on the chemical make-up of the solid. Thermoplastic polymers soften at the glass transition

temperature (Tg), Melt at Tm. Both thermoplastic and non-thermoplastic solids will

chemically decompose (pyrolyze) into lower molecular weight fragments. Chemical changes begin at Tp and continue through the temperature at which combustion occurs (Tc).

Limiting Oxygen Index (LOI). This is the amount of oxygen in the fuel mix needed to support combustion. The higher the number, the more difficult it is for combustion to occur.

NONDURABLES FLAME RETARDENT

1. Boric Acid/Borax. 2. Diammonium Phosphate and

Phosphoric Acid 3. Sulfamic Acid and Ammonium

Sulfamate

DURABLE FLAME RETARDANT

1. Tetrakis(hydroxymethyl)Phosphonium Derivatives Tetrakis(hydroxymethyl) phosphonium

Chloride (THPC) b. THPC-Urea Precondensate Tetrakis(hydroxymethyl)phosphonium

Hydroxide (THPOH)

2. N-Methyloldimethyl Phosphonopropioamide (PYROVATEX CP)

3. Phosphonic and Phosphoric Acid Derivatives

Limiting oxygen index (loi) Is the minimum concentration of oxygen,

expressed as a percentage, that will support combustion of a polymer. It is measured by passing a mixture of oxygen and nitrogen over a burning specimen, and reducing the oxygen level until a critical level is reached

CALENDARING

CALENDRING

Calendaring is a process where fabric is compressed by passing it between twoor more rolls under controlled conditions of time, temperature and pressure.

It is a type of mechanical finish

Produces different types of surface appearance1. Simple calendering2. Glazed calendering3. Ciŕe calendering4. Embossed calendering5. Moiré calendering6. Schreiner calendering

OBJECTS OF CALENDERING

To improve the fabric handle and to impart a smooth silky touch to the fabric

To compress the fabric and reduce its thickness

To reduce the air permeability by closing the threads

To increase the luster To reduce the yarn slippage To increase the opacity of the fabric Surface patterning by embossing

1. SIMPLE CALENDERING

It is a high speed, high pressure pressing of fabric (100 yds / min)

The high pressure flattens the yarn Smoothen the fabric Increases fabric lustre (fabric cover increases and more

light is reflected) Used for woven plain or twill weaves

Over-calendering however is to be avoided Yarns weakened out due to very high pressure

It is a temporary finish Yarns return to its natural cross section after first

laundering

2. GLAZED CALENDERING

It is a calendering finish to produce highly glazed / shined polished cotton

The calender machine used is a friction calender One cylinder of highly polished steel cylinder rotating at

speed much higher than the fabric passing through it

Fabrics are first treated with starches or resins before calendering The spaces between the yarns are thus filled up and

glazed appearance is obtained

Glazed calendering using starch are semi-durable

Glazed calendering using resins are durable

3. CIŔE CALENDERING It is a type of glazed calendering Here, the friction roller

rotates at speed much greater than ordinary friction calendering

The resulatant fabric become highly lustrous and takes on a wet lookCotton, rayon, polyester, nylon and blends can be given cire finish

Fabrics are however, treated with waxes and resins before friction calendering Highly polished effect is produced

When thermoplastic fabrics are ciŕe finished, they becomes moderately water-repellent Due to flattening Due to partially fusing of fibres

4. EMBOSSED CALENDERING

It is a calendering in which a three-dimensional design is created on a fabric

This is done on a special embossing calender in which the roller cylinder is engraved with the embossing design

The pattern is then pushed or shaped into the cloth when the fabric passes between the rollers

Some embossed fabrics are made to imitate more costly woven jacquard or dobby designs

Embossed patterns of fabrics treated with resins and cured after embossing are durable

Embossing of fabrics of thermoplastic fibres are permanent because the heated metal roll heat-sets the design

5. MOIRÉ CALENDERING

The moiré finish produces a wood-grain design on the face size of the fabric

Moiré finish can be temporary, durable or permanent Cotton or rayon moiré finish is temporary without

pretreatment with resin Durable moiré finish requires initial resin treatment

followed by calendering Moiré finish on thermoplastic fiber fabrics are permanent

if a heated roller is used for calendering

Methods of producing moiŕe Using engraved cylinder Using smooth calender roller

Using engraved cylinder In this case engraved roller is used on the calender roller Calender roller flattens one part of the fabric more than

other, causing different light reflectance The different light reflectance cause moire effect Definite repeat pattern moiŕe is produced

Using smooth calender rollers Two fabrics, each face to face, are fed through the

calender Ribbed fabrics are mainly required for this The high pressure on the calender rolls causes the rib to

squeeze into each other in certain areas Creates light reflectance pattern which produces moiŕe

effect The effect is completely random and has no specific

pattern

6. SCHREINER CALENDERING

Schreiner calendering produces a low, soft-key lustre on the fabric surface

Distinct from the high glaze of the glazing calender or the lustre shine of the simple calender

To produce this effect, one of the steel cylinders of the calender is embossed with fine diagonal lines. These embossing are barely visible in naked eye

Widely used on cotton & cotton/polyester sateen Schreiner calendering may be permanent, durable or

temporary finish Is permanent if the fibre is thermoplastic Is durable if the fabric is resin treated but not cured Is temporary if the fibre is non-thermoplastic and not

treated with resin

FULLING

During the traditional milling operation, fabrics of combed, carded or blended wool (nonscoured, scoured or carbonised and neutralised), at about 40°C, are soaked and in presence of special surfactants, are subjected to continuous pressure both in weft and warp direction. Under these conditions, wool fibres tend to felt, thus causing fabric shrinkage and a subsequent dynamic compacting. After this operation, the material must be washed to remove dirty water and the chemicals used.

Fulling is a permanent finish Used in wool fabrics Gradual or progressive felting of wool Done by carefully and controlled scouring or laundering The resultant fulled fabric is more compact and more

smoother Woollens are frequently heavily fulled Fabrics of worsted are usually very lightly fulled

MILLING MACHINES

NAPPING

It is a mechanical finish

Fibres being raised from woven/knitted fabrics by rotating, bristled, wire covered brushes

Overall effect is a raised fibres from fabric surface

Example: cotton flannel, rayon flannel, woollen and worsted napped fabric like kersey, melton

Napped fabrics have softer handle

Better insulation properties due to more air entrapment Mainly used as blankets, winter clothing

RAISING (NAPPING) MACHINE:1: ROLLER; 2: ROLLERS EQUIPPED WITH HOOKS;

3: FABRIC;4: NIB CLEANING BRUSHES;5: FABRIC TENSION ADJUSTMENT

RAISING THE FACE AND BACK OF THE FABRIC: A) SCHEME; B) VIEW

Problems are

Low resiliency and hence premature flattening occurs

Nap can be partially restored by frequent brushing

Subject to pilling

Rapid wear at abrasive points (like sleeve ends, elbows, button holes etc.)

Not recommended for hard wear

SUEDING

It is a mechanical finish

Similar to napping

Produces a soft, suede-like surface

Sand paper like material is used instead of rotating wire covered cylinder

PLISSÉ

Plissé is the name of the finish as well as the fabric produced with this finish

Permanent and chemical finish

Sodium hydroxide is printed on cotton fabric as a paste

Fabric shrinks only where the sodium hydroxide is applied, producing a puckered effect

Plissé fabric do not require ironing

When the sodium hydroxide is applied as lengthwise stripes, the fabric puckers and takes on the appearance of seersucker

Seersucker Lengthwise stripped puckered effect Produced by alternative stripes of loose and tight

warp yarns Plisse is a cheaper imitation of seersucker Plisse does not have that depth degree of pucker

that is common to seersucker Plisse puckers stretched out flat but seersucker do

not

SHEARING

A process to used to cut off surface fibers on fabrics

Uniforms the surface of napped fabrics to provide uniform pile height

High-speed cutting machine cuts the piles similar to that of a lawn mower

The blades in the machine are stationary and the fabric moves through the cutting blade

STIFFENING Some fabrics need to be made stiffer and more crisp as per

as the end use

Stiffening agents are applied to the cloth to build up the following properties To increase the weight of the fabric To improve the thickness To improve lustre

But, their effect is temporary and once the fabric is washed, most of the finishes are removed

STIFFENING Stiffening agents

Starches – finishing of cotton cloth. Ex: potato , wheat, corn

Dextrines – used for dyed and printed fabrics. No undue effect on the dye or print.

Natural gum – mainly used in printing as well as finishing process

Modified cellulose – CMC Resins

Acid stiffeningFine yarn cotton fabrics can be finished to be both stiff and

transparent by a process known as acid stiffening. It involves rapid immersion in sulphuric acid, followed by immediate neutralization in sodium hydroxide. The finish is permanent. This finish is also known as Organdi finish or Parchmentisation.

SOFTENING

Required for more pleasant hand and better drapability

Fabrics are harsher and stiffer because of their construction or due to some prior finishing process

Softening can be done by either mechanical or chemical process

Simple calendering softens hand, but it is temporary

Silicone compounds are used mostly as softner

Silicone finish is a durable finish and require curing

Different types of emulsified oils and waxes can be used but they are semi-durable finish

Different types of softners Anionic softners Cationic softners Non-ionic softners Reactive softners Emulsion softners Silicon softners

Anionic softners This is not fast to wash Compatible with resin Used in temporary finish with starch and cationic

product Ex; Sulphonated oils, fatty alcohol sulphates etc.

Non-ionic softners Have excellent stability against yellowing Not fast to dyeing No effect on in the shade of dyestuff

Cationic softners Substantive to cellulosic material Therefore, remain on cloth for few washes Produce yellowing on white fabrics Compatible with resins

Reactive softners Durable softners React chemically with the –OH groups of cellulose High cost Yellowing of treated fabric Toxic

Emulsion softners Popular because it reduces the loss of tear strength

on resin finish Fast to washing Give fuller appearance

Silicon softners Recently most used softners These are the manmade polymers based on the

frame work of alternate silicon and oxygen bonds with organic substituents attached to silicone

MECHANICAL SOFTENING MACHINE

SOIL RELEASE FINISH

SOIL RELEASE FINISH How??

Making the fibres more absorbent (hydrophilic) Permitting better wettability for improved soil removal Done by using hydrophilic finishes

Facilitates soil release during washing Prevent soil redeposition Also, reduce static charge by maintaining moisture on

the fabric surface Thus soil attraction during wear can be reduced

Mainly observed in polyester fabrics

SOIL RELEASE FINISH

What is soiling of textiles?

Textile material getting attracted to dirt or soil Development of static charge electricity to

hydrophilic textiles, making them prone to soiling Re-deposition of soil during washing

The soils cannot be readily removed Hydrophobic materials are not wetted properly

during laundering

SOIL RELEASE FINISH

What is soiling of textiles?

Soil release finish is a chemical finish

This permit easy removal of soil with ordinary laundering

Hydrophilic fibres and fabrics with resin finish are not easily wet able

Hence, stains of oily nature are not removed easily

Soil release finish increases the hydrophilicity of the material and increases wetability

Soil release finish also improves the antistatic properties, fabric drapability and comfort

WRINKLE RESISTANT FINISH

WRINKLE RESISTANCE FINISH The ability of the fabric to resist the formation of crease or wrinkle

when slightly squeezed is known as ‘crease resistance’ fabrics

The ability of a fabric to recover from a definite degree from creasing is called crease recovery

Finish to reduce the undue wrinkles on fabric or garments

Cotton, rayon and flax are more susceptible to wrinkle

Wrinkle occurs due to the hydrogen bonds of the cellulosic molecules in the amorphous region

Due to application of heat or moisture, the hydrogen bond breaks and new hydrogen bond occurs at new dimension

Therefore wrinkling can be reduced if the hydrogen bond formation can be reduced

Formaldehyde DMU ( Di-methylol urea) DMEU (Di-methylol ethylene urea) DMDHEU (Di-methylol di-hydroxyl ethylene

urea) Modified DMDHEU (Di-methylol di-hydroxyl

ethylene urea)

APPLICATION TECHNIQUE

Dry Process The classic process: the fabric is impregnated by

means of a padding unit (the quantity of finishis tuned by modifying the liquor concentration and the squeezing ratio) and dried at 100-120 °C in a stenter.

The cross-linking process occurs in the stenter, at temperatures varying according to the type of cross-linking agent used (generally 4-5 minutes at 150-160 °C).

Double treatment: the fabric is impregnated with a softener and dried at 100- 130 °C.

HUMID PROCESS The fabric is wetted by means of a padding unit

with a cross-linking agent and a catalyst solution; Then 6-8% of residual moisture is removed from

cotton (or 10-15% from other staple goods.) The fabric is then wound up on a roll, covered with a polyethylene sheet and left 16-24 hours to rest at ambient temperature.

Strong catalysts must be used for this process. The final effect depends on the residual

moisture: in case of low residual moisture content, the results will be similar to those obtained with the dry process whereas if the residual moisture content is high, the result is very similar to the cross-linking effect on wet substrates.

FRAGRANCE FINISH

FRAGRANCE FINISH Microencapsulation is a useful method for protecting various

functional finishes on textiles. As the capsules do not have affinity to fabrics, a binder should be used to fix the capsules for the purpose of finish durability.

Conventional fixation is a thermal process, in which a fabric is cured at 130-170°C for 1-10 minutes to make the components of the binder cross-link together, and tightly fix capsules on the fabric.

During curing, however, the aroma inside capsules can be lost through quick evaporation and swelling to escape or break the capsule. The loss from capsules can seriously reduce the amount of aroma on the fabric and decrease the durability.

An aroma capsule finished cotton fabric treated by a thermal curing process can only bear 25 wash cycles. To avoid the thermal process, an UV resin can be used to fix capsules because the resin can be cured under UV light at low temperatures in seconds. If a cotton fabric is finished with the selected aroma capsule and UV resin, and cured under the optimal conditions, the aroma function can withstand 50 wash cycles. Whiteness and stiffness of the finished fabrics were also examined.

ANTISTATIC FINISH

ANTISTATIC FINISH Synthetic fibres of hydrophobic nature are prone to

generation of static charges

This problem is very troublesome while processing the fabric at high speed in dry state

Antistatic agents are used

Antistatic agents absorb small amount of moisture from the atmosphere, thus reducing the dryness of the fabric

Antistatic finishes are semi-durable Washes out at several launderings or drycleanings

Permanent antistatic effects are obtainable manufactured fibres which are specially modified for this purpose (Ex: Antron III nylon fibre by Dupont & Cadon nylon fibres by Monsanto)

Pilling

Anti-pilling finishes: Pilling is an unpleasant phenomenon associated with

spun yarn fabrics especially when they contain synthetics.

Synthetic fibers are more readily brought to the surface of fabric due to their smooth surface and circular cross section and due to their higher tensile strength  and abrasion resistance, the pills formed take a long time to be abraded by wear.

With knit fabric, two more problems occur, viz., "picking" where the abrasion individual fibers work themselves out of yarn loops onto the surface when garment catches a pointed or rough object.

• Permanent Anti-static effects:

• Antistatic finish for synthetic textiles to avoid static charge build up & give a natural feel.

• Anti-static effective chemicals are largely chemically inert and require Thermosol or heat treatment for fixing on  polyester goods.

• In general Thermsolable anti-static agents also have a good soil release action which is as permanent as the anti-static effect.

• Anti-static finishes may also be of polyamide type being curable at moderate temperatures

• Non-Slip finishes:• Synthetic warp and weft threads in loosely woven fabrics are

particularly prone to slip because of their surface smoothness when the structure of fabric is disturbed and appearance is no loner attractive.

• To avoid this attempts are made to give the filaments a rougher surface.

• Silica-gel dispersions or silicic acid colloidal solutions are quite useful and they are used with advantage in combination with latex polymer or acrylates dispersions to get more permanent effect along with simultaneous improvement in resistance to pilling or snagging.

• These polymer finishes are also capable of imparting a soft and smooth handle to synthetic fabric without imparting water repellency

WASHES

Alters the look by different washing procedures

Mainly used for denim and similar items to have a faded and worn appearance

Have different methods Stone washing Acid washing Enzyme washing

Stone wash Stone washing transforms a new unworn garments

into used-looking faded garments

Done in garment form

Pumice stone are used

No chemicals are used for fading

Pumice stone are added to the laundry with the garments which abrade the garment Worn look Faded colour

The garment also become softer and obtain a casual look

Acid wash No acid is used

Pumice stones are soaked with oxidising bleaching agent (sodium hypochlorite)

Also known as ‘frosting’ or ‘ice washing’

The other procedure is same as that of the stone wash

Enzyme wash

Cellulase is used

Added to pumice stone or can be used separately While using pumice stone soaked with enzyme the

garment is laundered with the pumice stone

The cellulase attacks and weakens the cellulosic fibre

The surface colour of the denim comes out and colour fades off

ROT PROOFING OF CELLULOSE

Cellulosic fibres are made up of carbohydrate which is a food for fungi and microorganisms

The attack of these organism on the cellulosic materials cause rottening of them

To protect the cellulosic materials from such hazards rot-proof finishes are applied on cotton

Organo-lead componds Advantages

It does not affect the handle of the fabric It retains 100% of the fabric strength It does not discolour the fabric

Hg containing antibacterial agents Can be used in cotton as well as other cellulosic

materials