Wrinkle free finishing process

Introduction:

Cellulosic fiber-containing fabrics are made wrinkle resistant by a durable press wrinkle-free process which comprises treating a cellulosic fiber-containing fabric with formaldehyde, a catalyst capable of catalyzing the crosslinking reaction between the formaldehyde and cellulose and a silicone elastomer, heat-curing the treated cellulose fiber-containing fabric, preferably having a moisture content of more than 20% by weight, under conditions at which formaldehyde reacts with cellulose in the presence of the catalyst without a substantial loss of formaldehyde before the reaction of the formaldehyde with cellulose to improve the wrinkle resistance of the fabric in the presence of a silicone elastomeric softener to provide higher wrinkle resistance, and better tear strength after washing, with less treatment.

Types of Wrinkle Free Process of Cotton Shirts:

I guess the idea of a shirt which has not to be ironed anymore is as old as the cotton shirt itself. Apart from all attempts which has started decades ago to establish a shirt of Polyester or any other artificial fibre failed, as the consumer understood from the beginning the positive attributes of the cotton fibre. By its ability to hold moisture and to release it controlled, cotton is one of the most ideal fibres among all. It is breathable and remains a good feeling for the garment bearer. This may has changed by today´s new developments of artificial fibres, which have nothing to do with those from the sixties of the last century. But still the cotton fibre is number one in peoples mind when they think of comfort. In the last decade new technologies have been established to prepare the cotton fabric by chemicals, to make them almost wrinkle free or, as some manufacturer call it wrinkle resistant (WR). Basically four different technologies are known today to do so.

• Pre- Curing

• Post- Curing

• Dip- Spin

• Vapor – Phase 

But, what basically happens during or after this process ?

All four systems have one issue in common, the cotton fibre is swelled artificially and by this process it is loosing its memory. Instead of being curled as it naturally is, it becomes straight. And as it has increased its diameter, it is almost impossible to crease. The negative aspect is, that by this process it looses a part of its tensile strength and habit to absorb moisture.

 

Pre- Cured fabric:

Fabric can be a 100 % cotton fabric or cotton blend.Contrary to all the other WR processes, by this system the fabric does not need any further heat treatment as the curing process has been done already before the shirt is manufactured. The already finished fabric is resistant to wrinkles already. Unfortunately no crisp and sharp creases can be realist for collars, cuffs and front placket edges. As the fabric does not accept any final pressing.Only a shirt finisher with steam and air is required.

Post- Cured fabric:

In this case the fabric can be a 100 % cotton fabric or a cotton blend. The fabric will be delivered with the curing chemical inside. The roll of fabric is sealed in a polyester bag . Once the bag is opened the fabric has to be manufactured entirely, as it cannot be stored for a long time. After the shirt is manufactured, it has to be pressed entirely. After it has been put on a hanger it will be cured in a hanging position on a cloth rack inside an oven for 3- 5 min. by about 130°C to 150”C (depends on the chemical used).

Now the shirt is ready for folding and bagging.

Dip- Spin system:

This one belongs to the most popular process for wrinkle free shirts and can be used for 100 % cotton fabrics or cotton blends. After the shirt is manufactured as usually, it will be dipped into a mixture of chemicals, which will be absorbed by the cotton fibres. After the treatment in a tumbler the shirt is still moisturized and has to be pressed entirely. Important is, that during the pressing operation on the various Veit- Kannegiesser Collar-, Cuff- and Body- Presses, the curing process will start already. After pressing the shirt will be put on a hanger and can be cured in a curing oven by about 140°C for about 3 -5 min. One of the key factors for a perfect appearance is the pressing quality, as after the curing operation in an oven, all wrinkles will stay for life. A re-touching by an iron is impossible.
 

 Vapor – Phase:

This curing system can be used in some countries only as very aggressive chemicals are used. Similar to the DIP SPIN system the shirt is manufactured as usually. After the final pressing, a special curing oven is used as instead of liquid chemicals, gas is used to make the shirt resistant to wrinkles. The gas is circulating through the oven and penetrates into the cotton fibre. After a while the gas has to be evacuated from the oven. Before the shirt is folded and bagged, it needs to be washed in order to remove left chemicals inside.

Easy-care and Durable Press Finishes of Cellulosics

Introduction 
Easy-care and durable press finishes are generally applied to cellulose and cellulose blends fabrics, but other fibers can benefit from these finishes. There are many words and phrases available to describe this application;
–Easy-Care

–Durable press
–Minimum care

–Easy to iron
–No-iron

–Wash and wear
–Crease resistant

–Permanent press
–Shrink proof

–Wrinkle resistant
–Wrinkle free
The most technically correct description would be “Cellulosic anti-swelling” or “Cellulosic cross linking“ finishes.
In addition to the dimensional stability properties, the sheen of calendered fabrics (permanent chintz) and the stand and hand of pile fabrics are generally improved by resin finishes.
The primary effects of easy-care finishes on cellulose are:
–Reduction in swelling and shrinkage
–Improved wet and dry wrinkle recovery (*CRA)
–Smoothness of appearance after drying.
–Retention of intentional creases and pleats.
* CRA (crease recovery angle), is the sum of the crease recovery angles of warp and the fill directions of the fabric, increases from about 150° to about 300°
An unavoidable side effect of the cellulosic crosslinking finishes is reduction in elasticity and flexibility of the cellulose fibers. This produces a considerable decrease in abrasion resistance, tear and tensile strength on cellulose.

Mechanisms of easy-care finishes

The primary cause of shrinkage of cellulosic fibers is the fact that these fibers can readily absorb moisture. This absorbed moisture facilitates internal polymer chain movements in the amorphous fiber areas by lubrication. It disrupts the internal hydrogen bonding between these polymer chains. When a moisture laden cellulosic fiber is stressed, the internal polymer chains of amorphous areas are free to move to relieve that stress. Hydrogen bonds can reform between the polymer chains in their sifted position. With no restoring forces available, a newly formed wrinkle or crease will remain until additional processes (ironing for example) apply adequate moisture and mechanical forces to overcome the internal forces.
The swelling of cellulosic fibers by moisture can be reduced by application of self crosslinking urea or melamine products as well as products that mainly crosslink with cellulose molecules.
Without such a crosslinking finish, cellulose fibers can take up more than 10% of their weight in water. As the fibers swell, the fabric must crease and shrink to relieve the internal stress caused by swelling.
Two different chemical approaches have been used commercially to produce non-swelling or durable press cellulose fabrics.
-The incorporation of a polymerized finish in the pores of the fibers, so that water molecules cannot easily penetrate the fiber.
–The reaction of multifunctional crosslinking agents with hydroxyl groups of adjacent cellulose molecules that hinder the swelling of cellulose fibers. Chemistry of easy-care finishes: 

1. Formaldehyde containing resins:

a. Urea formaldehyde resins (DMU):

i. Highly reactive. It has to be used within a few hours in the finishing bath
ii. Low stability to hydrolysis, low durability to laundering
iii. High Chlorine retention
iv. High content and release of formaldehyde
v. Very high elastic resilience
vi. End product: DMU (Dimetoxymethyl urea) 

b. Melamine-formaldehyde resins:

i. These products are mostly three to six reactive N-methylol groups connected to one melamine ring. This leads to a higher crosslinking and easy-care finish with better wash fastness.

ii.These products provide tri-to hexamethylol melamine (TMM, HMM) and their methyl ethers.
iii.TMM is preferred for easy-care finish, often only as a component of product mixture to give a better performance of effects. It is also used for permanent chintz of cellulose. These products produce firmer hands than HMM and are extensively used as hand builders.
iv. Properties of melamine-formaldehyde resins:
1) Better stability to hydrolysis and better washing durability.
2) Relatively high formaldehyde content and release
3) Better chlorine retention than DMU.
4) More dimensional stability and stiffness (also nylon and polyester) 

c. Glyoxal Resins:N,N-Dimethylol-4,5-dihydoxyethylene urea (DMDHEU):

i. This chemical is the basis for about 90% of easy-care and durable press finish products on the market. DMDHEU is synthesized from urea, glyoxal and formaldehyde.
ii. It is less reactive than DMU and TMM and therefore requires more active catalyst.
iii. It is more stable than finish baths with DMU and TMM.

d. Formaldehyde in Fabrics:

i. Free formaldehyde: Free formaldehyde is defined as the uncombined monomeric formaldehyde that exists in finish solution.
ii. Formaldehyde release: Formaldehyde release is the amount of formaldehyde that escapes from a fabric into the atmosphere. 

e. Linkages responsible for formaldehyde release:

i. Cellulose readily picks-up formaldehyde from the atmosphere. This will give positive reading during testing.
ii. Sources of gaseous formaldehyde are uncured resin or pendant N-methylol groups. It is difficult to cure 100% of the resin that is applied and make sure there are no pendant N-methylol groups left.

iii. The third source of released formaldehyde is the crosslink itself. The finish will decompose under certain test conditions and liberate formaldehyde.

2. The main properties of DMDHEU based products: 

a. Low to very low reactivity (when ether modified)
b. Excellent durability and laundering.
c. Low chlorine retention
d. Medium to very low formaldehyde release.
e. The most commonly used durable press products.

3. Non-formaldehyde containing products(DMeDHEU): 

a. DMeDHEU doesn’t contain formaldehyde. It is synthesized from the relatively expensive N,N-dimethyl urea and glyoxal.
b. Like DMDHEU, it can be modified by reaction with alcohols such as methanol, diethylene glycol or 1,6-hexanediol to ether derivatives.
c. These products are less reactive than DMDHEU types because of their hydroxyl groups. Stronger catalysts or harsher reaction conditions are needed for successful crosslinking.
d. DMeDHEU costs about twice as much as DMDHEU products.
e. In order to achieve comparable easy-care and durable press effects to DMDHEU, nearly twice the amount of DMeDHEU is needed. However, a1:1 mixture of DMDHEU and DMeDHEU is popular because of its reduced formaldehyde levels with slightly inferior physical properties at an acceptable cost. 

4. The main properties of DMeDHEU products: 

a. Formaldehyde free
b. Very low reactivity
c. Very low chlorine retention.
d. Limited durability to laundering
e. Yellowing effect when not ether modified
f. Development of unpleasant odors, depending on the product formulation
5. Catalysts for easy-care and durable press finishes
a. The reaction of DMDHEU with cellulose requires an acid catalyst for acceptable yields under conditions suitable for textile processing.
b. The most common catalysts are Lewis acids such as magnesium chloride and zinc nitrate that generate acid conditions during curing process, thus providing neutral liquors and good finish bath stability.
c. Sulfuric and hydrochloric acids and their ammonium salts serve as excellent catalysts but also lead to undesirable fiber degradation.
d. Often citric acid is combined with Lewis acid to provide additional boost to reactions especially for short shock condensation.
e. Under acidic conditions, DMDHEU products react via oxygen protonation.

Fabric properties:

1. DP performance Vs Add-on 
a. There is a sharp increase in wrinkle recovery with increasing resin level. As bath concentration approaches 7% DMDHEU (pure), wrinkle recovery and DP rating begin to levels-off. Above this level, the rate of improvement is less rapid and only modest gains are obtained with massive amounts of resin.
2. Tensile strength and abrasion resistancea. Losses in tensile and abrasion resistance in 100% cotton are directly related to the number of cross-links.3. Crease recovery versus temperature
a. Avoid flash curing (Curing in a very short time)4. Points to considera. Losses in physical properties due to rigidification of fiber are unavoidable. Losses in strength due to cross-links can be recovered by mild acid strip. Boiling 1 hour in 1% phosphoric acid buffered with urea will remove almost all cross-links and restore about 70% of lost strength.
b. Catalyst damage also lead to losses in physical properties. That portion of the lost not recovered by acid strip. The best to avoid this problem is to use mild catalyst and avoid over curing.
5. Chlorine resistancea. The term chlorine resistance encompasses two problems
b. Yellowing of fabric by the bleach
c. Tendering (strength loss)
i. Residual–NH groups are responsible for this problem (because of the formation of chloramides)6. Fabric odora. Finished fabrics are beset by two types of odors, fish odor and formaldehyde odor. Some over cured fabrics develop an unpleasant burnt or fish odor. Fish odor is trimethyl amine which is produced by reaction of free formaldehyde with ammonia.

Application of easy-care finishes:

1. The traditional pad-dry-cure method is a dry curing process. All of the water has been removed from fabric prior to the actual crosslinking reaction.
2. It is also possible to crosslink cellulose in a wet process. Fabric padded at 80% wet pick-up with the finishing chemicals is wrapped in plastic film and batched at room temperature for about 24 hours before washing and drying. The water content of the cellulose fibers during the crosslinking step greatly affects the final fabric properties.
3. Normally a high dry crease recovery angle is preferred because the appearance of the dry textile is more important than the wet one. Between these two extremes is the ’’moist cure’’: a 5-20 hours room temperature reaction with 6% above normal moisture regain. The fabric properties of moist cure are a good compromise between the extremes of ‘’dry’’ and ‘’wet’’ process. The moist cure preferred when high tear strength of finished fabric is required.
4. A main difficulty of moist cure is humidity control (6-10%).

Textile Manufacturing Technology

 
Textile manufacture is a major industry. It is based in the conversion of three types of fibreyarn, then (fiber is an alternative spelling in the US but not in Britain and the Commonwealth) into fabric, then textiles. These are then fabricated into clothes or other artifacts. Cotton remains the most important natural fibre, so is treated in depth. There are many sources of fibre, and variable processes available at the spinning and fabric-forming stages coupled with the complexities of the finishing and colouration processes to the production of a wide ranges of products. There remains a large industry that uses hand techniques to achieve the same results.

Processing of Cotton:

Cotton is the world's most important natural fibre. In the year 2007, the global yield was 25 million tons from 35 million hectares cultivated in more than 50 countries.

There are five stages:1. Cultivating and Harvesting
2. Preparatory Processes
3. Spinning
4. Weaving
5. Finishing

Cultivating and harvesting:Cotton is grown anywhere with long, hot dry summers with plenty of sunshine and low humidity. Indian cotton, gossypium arboreum is finer but the staple is only suitable for hand processing. American cotton, gossypium hirsutum produces the longer staple needed for machine production. Planting is from September to mid November and the crop is harvested between March and May. The cotton bolls are harvested by stripper harvesters and spindle pickers, that remove the entire boll from the plant. The cotton boll is the seed pod of the cotton plant, attached to each of the thousands of seeds are fibres about 2.5 cm long.

Ginning:
The seed cotton goes in to a Cotton Gin. The cotton gin separates the seeds and removes the "trash" (dirt, stems and leaves) from the fibre. In a saw gin, circular saw grab the fibre and pull it through a grating that is too narrow for he seeds to pass. A roller gin is used with longer staple cotton,. Here a leather roller captures the cotton. A knife blade, set close to the roller detaches the seed. by drawing them through teeth in circular saws and revolving brushes which clean them away.
The ginned cotton fibre, known as lint, is then compressed into bales which are about 1.5m tall and weigh almost 220 kg. Only 33% of the crop is usable lint. Commercial cotton is priced by quality, and that broadly relates to the average length of the staple, and the variety of the plant. Longer staple cotton ( 2 1/2 in to 1 1/4 in) is called Egyptian, medium staple ( 1 1/4 in to 3/4 in) is called American upland and short staple ( less than 3/4 in) is called Indian.
The cotton seed is pressed into a cooking oil. The husks and meal are processed into animal feed, and the stems into paper.

Issues:

Cotton is farmed intensively and uses large amounts of fertiliser and 25% of the worlds insecticide. Native Indian variety were rainwater fed, but modern hybrids used for the mills need irrigation, which spreads pests. The 5% of cotton bearing land in India uses 55% of all pesticides.[3] Before mechanisation, cotton was havested manually and this unpleasant task was done by the lower castes, and in the United States by slaves of African origin.

Preparatory Processes- Preparation of yarn:
1. Ginning, bale-making and transportation is done in the country of origin.
 
2. Opening and cleaning:

Cotton mills get the cotton shipped to them in large, 500 pound bales. When the cotton comes out of a bale, it is all packed together and still contains vegetable matter. The bale is broken open using a machine with large spikes. It is called an Opener.In order to fluff up the cotton and remove the vegetable matter, the cotton is sent through a picker, or similar machines. A picker looks similar to the carding machine and the cotton gin, but is slightly different. The cotton is fed into the machine and gets beaten with a beater bar, to loosen it up. It is fed through various rollers, which serve to remove the vegetable matter. The cotton, aided by fans, then collects on a screen and gets fed through more rollers till it emerges as a continuous soft fleecy sheet, known as a lap. 

3. Blending:
Mixing & Scutching 4.Carding:

the fibres are separated and then assembled into a loose strand (sliver or tow) at the conclusion of this stage. The cotton comes off of the picking machine in laps, and is then taken to carding machines. The carders line up the fibres nicely to make them easier to spin. The carding machine consists mainly of one big roller with smaller ones surrounding it. All of the rollers are covered in small teeth, and as the cotton progresses further on the teeth get finer (i.e. closer together). The cotton leaves the carding machine in the form of a sliver; a large rope of fibres.
Note: In a wider sense Carding can refer to these four processes: Willowing- loosening the fibres; Lapping- removing the dust to create a flat sheet or lap of cotton; Carding- combing the tangled lap into a thick rope of 1/2 in in diameter, a sliver; and Drawing- where a drawing frame combines 4 slivers into one- repeated for increased quality.

5. Combing is optional,but is used to remove the shorter fibres, creating a stronger yarn.

6. Drawing the fibres are straightened:
Several slivers are combined. Each sliver will have thin and thick spots, and by combining several slivers together a more consistent size can be reached. Since combining several slivers produces a very thick rope of cotton fibres, directly after being combined the slivers are separated into rovings. These rovings are then what are used in the spinning process. Generally speaking, for machine processing a roving is about the width of a pencil.Next, several slivers are combined. Each sliver will have thin and thick spots, and by combining several slivers together a more consistent size can be reached. Since combining several slivers produces a very thick rope of cotton fibres, directly after being combined the slivers are separated into rovings. These rovings (or slubbings) are then what are used in the spinning process.
Generally speaking, for machine processing, a roving is about the width of a pencil.
Drawing frame: Draws the strand out
Slubbing Frame: adds twist, and winds on to bobbins
Intermediate Frames: are used to repeat the slubbing process to produce a finer yarn.
Roving frames: reduces to a finer thread, gives more twist, makes more regular and even in thickness, and winds on to a smaller tube.
Spinning- Yarn manufacture:
The spinning machines take the roving, thins it and twists it, creating yarn which it winds onto a bobbin.In mule spinning he roving is pulled off a bobbin and fed through some rollers, which are feeding at several different speeds.This thins the roving at a consistent rate. If the roving was not a consistent size, then this step could cause a break in the yarn, or could jam the machine. The yarn is twisted through the spinning of the bobbin as the carriage moves out, and is rolled onto a cop as the carriage returns. Mule spinning produces a finer thread than the less skilled ring spinning.The mule was an intermittent process, as the frame advanced and returned a distance of 5ft.It was the descendant of 1779 Crompton device. It produces a softer less twisted thread that was favoured for fines and for weft. It requires considerable skill, so was womens work. The ring was a descendant of the Arkwright water Frame 1769. It was a continuous process, the yard was coarser, had a greater twist and was stronger so was suited to be warp. Requiring less skill it was mens work. Ring spinning is slow due to the distance the thread must pass around the ring, other methods have been introduced. These are collectively known as Break or Open-end spinning.
Sewing thread, was made of several threads twisted together, or doubled.

Checking:This is the process where each of the bobbins is rewound to give a tighter bobbin.

Folding and twisting:Plying is done by pulling yarn from two or more bobbins and twisting it together, in the opposite direction that that in which it was spun. Depending on the weight desired, the cotton may or may not be plied, and the number of strands twisted together varies.

Gassing:

Gassing is the process of passing yarn, as distinct from fabric very rapidly through a series of Bunsen gas flames in a gassing frame, in order to burn off the projecting fibres and make the thread round and smooth and also brighter. Only the better qualities of yarn are gassed, such as that used for voiles, poplins, venetians, gabardines, many Egyptian qualities, etc. There is a loss of weight in gassing, which varies' about 5 to 8 per cent., so that if a 2/60's yarn is required 2/56's would be used. The gassed yarn is darker in shade afterwards, but should not be scorched.

Measurements:

1. Cotton Counts: The number of pieces of thread, 840 yards long needed to make up 1 lb weight. 10 count cotton means that 10x840 yds weighs 1lb. This is coarser than 20 count cotton where 20x840 yards are needed.
2. Hank: A length of 7 leas or 840 yards
3,Thread: A length of 54 in (the circumference of a warp beam)
4.Bundle: Usually 10 lbs
5.Lea: A length of 80 threads or 120 yards.
6.Denier: this is an alternative method. It is defined as a number that is equivalent to the weight in grams of 9000m of a single yarn. 15 denier is finer than 30 denier.
7.Tex: is the weight in grams of 1km of yarn.

Weaving-Fabric manufacture:
The weaving process uses a loom. The lengthway threads are known as the warp, and the cross way threads are known as the weft. The warp which must be strong needs to be presented to loom on a warp beam. The weft, passes across the loom in a shuttle, that carries the yarn on a pirn. These pirns are automatically changed by the loom. Thus, the yarn needs to be wrapped onto a beam, and onto pirns before weaving can commence. 

Winding:After being spun and plied, the cotton thread is taken to a warping room where the winding machine takes the required length of yarn and winds it onto warpers bobbins.

Warping or beaming:

Racks of bobbins are set up to hold the thread while it is rolled onto the warp bar of a loom. Because the thread is fine, often three of these would be combined to get the desired thread count.[citation needed].

Sizing:

Slasher sizing machine needed for strengthening the warp by adding starch.

Drawing in Looming:The process of drawing each end of the warp separately through the dents of the reed and the eyes of the healds, in the order indicated by the draft.

Pirnting (Processing the weft):Pirn winding frame was used to transfer the weft from cheeses of yarn onto the pirns that would fit into the shuttle.

Weaving:At this point, the thread is woven. Depending on the era, one person could manage anywhere from 3 to 100 machines. In the mid nineteenth century, four was the standard number. A skilled weaver in 1925 would run 6 Lancashire Looms. As time progressed new mechanisms were added that stopped the loom any time something went wrong. The mechanisms checked for such things as a broken warp thread, broken weft thread, the shuttle going straight across, and if the shuttle was empty. Forty of these Northrop Looms or automatic looms could be operated by one skilled worker.
 

The three primary movements of a loom are shedding, picking, and beating-up.
 
Shedding: The operation of dividing the warp into two lines, so that the shuttle can pass between these lines. There are two general kinds of sheds-"open" and "closed." Open Shed-The warp threads are moved when the pattern requires it-from one line to the other. Closed Shed-The warp threads are all placed level in one line after each pick. 

Picking:The operation of projecting the shuttle from side to side of the loom through the division in the warp threads. This is done by the overpick or underpick motions. The overpick is suitable for quick-running looms, whereas the underpick is best for heavy or slow looms.

Beating-up: The third primary movement of the loom when making cloth, and is the action of the reed as it drives each pick of weft to the fell of the cloth.
A Cartwright Loom was an early power loom, that stopped each time the pirn was empty are needed an operative to replace the shuttle. Jacquard Looms and Dobby Looms are looms that have sophisticated methods of shedding. They may be separate looms, or mechanisms added to a plain loom.

Measurements:

Ends and Picks: Picks refer to the weft, ends refer to the warp. The coarseness of the cloth can be expressed as the number of picks and ends per quarter inch square , or per inch square. Ends is always written first. For example: Heavy domestics are made from coarse yarns, such as 10's to 14's warp and weft, and about 48 ends and 52 picks.

Associated job titles:1. Piecer
2. Scavenger
3. Weaver
4. Tackler
5. Draw boy
6. Pirner

Issues:
When a hand loom was located in the home, children helped with the weaving process from an early age. Piecing needs dexterity, and a child can be a productive as an adult. When weaving moves from the home to the mill, children were often allowed to help their older sisters, and laws have to be made to prevent Child Labour becoming established.

Knitting- Fabric manufacture:

Knitting by machine is done in two different ways; warp and weft. Weft knitting (as seen in the pictures) is similar in method to hand knitting with stitches all connected to each other horizontally. Various weft machines can be configured to produce textiles from a single spool of yarn or multiple spools depending on the size of the machine cylinder (where the needles are bedded). In a warp knit there are many pieces of yarn and there are vertical chains, zigzagged together by crossing the yarn.
Warp knits do not stretch as much as a weft knit, and it is run-resistant. A weft knit is not run-resistant, but stretches more, this is especially true if spools of Lycra are processed from separate spool containers and interwoven through the cylinder with cotton yarn giving the finished product more flexibilty making it less prone to having a 'baggy' appearance. The average t-shirt is a weft knit. 


Finishing- Processing of Textiles:The grey cloth,woven cotton fabric in its loom-state, not only contains impurities, including warp size, but requires further treatment in order to develop its full textile potential. Furthermore, it may receive considerable added value by applying one or more finishing processes.

Desizing:
Depending on the size that has been used, the cloth may be steeped in a dilute acid and then rinsed, or enzymes may be used to break down the size.

Scouring:Scouring, is a chemical washing process carried out on cotton fabric to remove natural wax and non-fibrous impurities (eg the remains of seed fragments) from the fibres and any added soiling or dirt. Scouring is usually carried in iron vessels called kiers. The fabric is boiled in an alkali, which forms a soap with free fatty acids. (saponification). A kier is usually enclosed, so the solution of sodium hydroxide can be boiled under pressure, excluding oxygen which would degrade the cellulose in the fibre. If the appropriate reagents are used, scouring will also remove size from the fabric although desizing often precedes scouring and is considered to be a separate process known as fabric preparation. Preparation and scouring are prerequisites to most of the other finishing processes. At this stage even the most naturally white cotton fibres are yellowish, and bleaching, the next process, is required.

Bleaching:Bleaching improves whiteness by removing natural coloration and remaining trace impurities from the cotton; the degree of bleaching necessary is determined by the required whiteness and absorbency. Cotton being a vegetable fibre will be bleached using an oxidizing agent, such as dilute sodium hydrochlorite or dilute hydrogen peroxide. If the fabric is to be dyed a deep shade, then lower levels of bleaching are acceptable, for example. However, for white bed sheetings and medical applications, the highest levels of whiteness and absorbency are essential.

Mercerising:
A further possibility is mercerizing during which the fabric is treated with caustic soda solution to cause swelling of the fibres. This results in improved lustre, strength and dye affinity. Cotton is mercerized under tension, and all alkali must be washed out before the tension is released or shrinkage will take place. Mercerizing can take place directly on grey cloth, or after bleaching.
Many other chemical treatments may be applied to cotton fabrics to produce low flammability, crease resist and other special effects but four important non-chemical finishing treatments are:

Singeing:

Singeing is designed to burn off the surface fibres from the fabric to produce smoothness. The fabric passes over brushes to raise the fibres, then passes over a plate heated by gas flames.
 

Raising:

Another finishing process is raising. During raising, the fabric surface is treated with sharp teeth to lift the surface fibres, thereby imparting hairiness, softness and warmth, as in flannelette. 

Calendering:
Calendering is the third important mechanical process, in which the fabric is passed between heated rollers to generate smooth, polished or embossed effects depending on roller surface properties and relative speeds.

Shrinking (Sanforizing):
Finally, mechanical shrinking (sometimes referred to as sanforizing), whereby the fabric is forced to shrink width and/or lengthwise, creates a fabric in which any residual tendency to shrink after subsequent laundering is minimal.

Dyeing:Finally, cotton is an absorbent fibre which responds readily to colouration processes. Dyeing, for instance, is commonly carried out with an anionic direct dye by completely immersing the fabric (or yarn) in an aqueous dyebath according to a prescribed procedure. For improved fastness to washing, rubbing and light, other dyes such as vats and reactives are commonly used. These require more complex chemistry during processing and are thus more expensive to apply.

Printing:

Printing, on the other hand, is the application of colour in the form of a paste or ink to the surface of a fabric, in a predetermined pattern. It may be considered as localised dyeing. Printing designs on to already dyed fabric is also possible.

Economic, environmental and political consequences of cotton manufacture:

The growth of cotton is divided into two segments i.e. organic and genetically modified. Cotton crop provides livelihood to millions of people but its production is becoming expensive because of high water consumption, use of expensive pesticides, insecticides and fertiliser. GM products aim to increase disease resistance and reduce the water required. The organic sector was worth $583 million. GM cotton, in 2007, occupied 43% of cotton growing areas..
The consumption of energy in form of water and electricity is relatively high, especially in processes like washing, de-sizing, bleaching, rinsing, dyeing, printing, coating and finishing. Processing is time consuming. The major portion of water in textile industry is used for wet processing of textile (70 per cent). Approximately 25 per cent of energy in the total textile production like fibre production, spinning, twisting, weaving, knitting, clothing manufacturing etc. is used in dyeing. About 34 per cent of energy is consumed in spinning, 23 per cent in weaving, 38 per cent in chemical wet processing and five per cent in miscellaneous processes. Power dominates consumption pattern in spinning and weaving, while thermal energy is the major factor for chemical wet processing.

Processing of other vegetable fibres- other processes:

Flax
Hemp
Jute

Processing of Protein fibres:
Wool and Worsted, 
Silk
Angora.

Processing & Discussion of types of man made fibres:

Synthetic fibres are the result of extensive development by scientists to improve upon the naturally occurring animal and plant fibres. In general, synthetic fibres are created by forcing, or extruding, fibre forming materials through holes (called spinnerets) into the air, thus forming a thread. Before synthetic fibres were developed, artificially manufactured fibers were made from cellulose, which comes from plants.
The first artificial fibre, known as artificial silk from 1799 onwards, became known as viscose around 1894, and finally rayon in 1924. A similar product known as cellulose acetate was discovered in 1865. Rayon and acetate are both artificial fibres, but not truly synthetic, being made from wood. Although these artificial fibres were discovered in the mid-nineteenth century, successful modern manufacture began much later in the 1930's. Nylon, the first synthetic fibre, made its debut in the United States as a replacement for silk, and was used for parachutes and other military uses.[citation needed]
The techniques used to process these fibres in yarn are essentially the same as with natural fibres, modifications have to be made as these fibers are of great length, and have no texture such as the scales in cotton and wool that aid meshing.

History of Clothing and Textiles Material.

 
History:

The production of textiles is a craft whose speed and scale of production has been altered almost beyond recognition by industrialization and the introduction of modern manufacturing techniques. However, for the main types of textiles, plain weave, twill or satin weave, there is little difference between the ancient and modern methods.
 
Incans have been crafting quipus (or khipus) made of fibres either from a protein, such as spun and plied thread like wool or hair from camelids such as alpacas, llamas and camels or from a cellulose like cotton for thousands of years. Khipus are a series of knots along pieces of string. They have been believed to only have acted as a form of accounting, although new evidence conducted by Harvard professor, Gary Urton, indicates there may be more to the khipu than just numbers. Preservation of khipus found in museum and archive collections follow general textile preservation principles and practice.
 
Uses:

Textiles have an assortment of uses, the most common of which are for clothing and containers such as bags and baskets. In the household, they are used in carpeting, upholstered furnishings, window shades, towels, covering for tables, beds, and other flat surfaces, and in art. In the workplace, they are used in industrial and scientific processes such as filtering. Miscellaneous uses include flags, backpacks, tents, nets, cleaning devices, such as handkerchiefs; transportation devices such as balloons, kites, sails, and parachutes; and strengthening in composite materials such as fibre glass and industrial geotextiles. Textiles can be used for educational purposes. Textiles can be used as a material for children to use and explore in their classrooms as another element of learning. Children can manipulate and come up with creative uses for textiles such as collage materials, art materials and so on.
 
Textiles used for industrial purposes, and chosen for characteristics other than their appearance, are commonly referred to as technical textiles. Technical textiles include textile structures for automotive applications, medical textiles (e.g. implants), geotextiles (reinforcement of embankments), agrotextiles (textiles for crop protection), protective clothing (e.g. against heat and radiation for fire fighter clothing, against molten metals for welders, stab protection, and bullet proof vests. In all these applications stringent performance requirements must be met. Woven of threads coated with zinc oxide nanowires, laboratory fabric has been shown capable of "self-powering nanosystems" using vibrations created by everyday actions like wind or body movements.

Fashion and textile designs:

Fashion designers commonly rely on textile designs to set their fashion collections apart from others. Marisol Deluna, Nicole Miller, Lilly Pulitzer, the late Gianni Versace and Emilio Pucci can be easily recognized by their signature print driven designs.

Sources and types:

Textiles can be made from many materials. These materials come from four main sources: animal, plant, mineral, and synthetic. In the past, all textiles were made from natural fibres, including plant, animal, and mineral sources. In the 20th century, these were supplemented by artificial fibres made from petroleum.
Textiles are made in various strengths and degrees of durability, from the finest gossamer to the sturdiest canvas. The relative thickness of fibres in cloth is measured in deniers. Microfibre refers to fibres made of strands thinner than one denier.

Animal textiles:

Animal textiles are commonly made from hair or fur.Wool refers to the hair of the domestic goat or sheep, which is distinguished from other types of animal hair in that the individual strands are coated with scales and tightly crimped, and the wool as a whole is coated with an oil known as lanolin, which is waterproof and dirtproof. Woollen refers to a bulkier yarn produced from carded, non-parallel fibre, while worsted refers to a finer yarn which is spun from longer fibres which have been combed to be parallel. Wool is commonly used for warm clothing. Cashmere, the hair of the Indian cashmere goat, and mohair, the hair of the North African angora goat, are types of wool known for their softness.
Other animal textiles which are made from hair or fur are alpaca wool, vicuña wool, llama wool, and camel hair, generally used in the production of coats, jackets, ponchos, blankets, and other warm coverings. Angora refers to the long, thick, soft hair of the angora rabbit.
Wadmal is a coarse cloth made of wool, produced in Scandinavia, mostly 1000~1500CE.
Silk is an animal textile made from the fibres of the cocoon of the Chinese silkworm. This is spun into a smooth, shiny fabric prized for its sleek texture.

Plant textiles:

Grass, rush, hemp, and sisal are all used in making rope. In the first two, the entire plant is used for this purpose, while in the last two, only fibres from the plant are utilized. Coir (coconut fibre) is used in making twine, and also in floormats, doormats, brushes, mattresses, floor tiles, and sacking.Straw and bamboo are both used to make hats. Straw, a dried form of grass, is also used for stuffing, as is kapok.
Fibres from pulpwood trees, cotton, rice, hemp, and nettle are used in making paper.
Cotton, flax, jute, hemp and modal are all used in clothing. Piña (pineapple fibre) and ramie are also fibres used in clothing, generally with a blend of other fabrics such as cotton.
Acetate is used to increase the shininess of certain fabrics such as silks, velvets, and taffetas.
Seaweed is used in the production of textiles. A water-soluble fibre known as alginate is produced and is used as a holding fibre; when the cloth is finished, the alginate is dissolved, leaving an open area .Tencel is a man-made fabric derived from wood pulp. It is often described as a man-made silk equivalent and is a tough fabric which is often blended with other fabrics - cotton for example.

Mineral textiles:

Asbestos and basalt fibre are used for vinyl tiles, sheeting, and adhesives, "transite" panels and siding, acoustical ceilings, stage curtains, and fire blankets.Glass Fibre is used in the production of spacesuits, ironing board and mattress covers, ropes and cables, reinforcement fibre for composite materials, insect netting, flame-retardant and protective fabric, soundproof, fireproof, and insulating fibres.Metal fibre, metal foil, and metal wire have a variety of uses, including the production of cloth-of-gold and jewelry. Hardware cloth is a coarse weave of steel wire, used in construction.

Synthetic textiles:

All synthetic textiles are used primarily in the production of clothing.
Polyester fibre is used in all types of clothing, either alone or blended with fibres such as cotton. AramidTwaron) is used for flame-retardant clothing, cut-protection, and armor. fibre (e.g. Acrylic is a fibre used to imitate wools, including cashmere, and is often used in replacement of them. Nylon is a fibre used to imitate silk; it is used in the production of pantyhose. Thicker nylon fibres are used in rope and outdoor clothing.
Spandex (trade name Lycra) is a polyurethane fibre that stretches easily and can be made tight-fitting without impeding movement. It is used to make activewear, bras, and swimsuits.Olefin fibre is a fibre used in activewear, linings, and warm clothing. Olefins are hydrophobic, allowing them to dry quickly. A sintered felt of olefin fibres is sold under the trade name Tyvek.Ingeo is a polylactide fibre blended with other fibres such as cotton and used in clothing. It is more hydrophilic than most other synthetics, allowing it to wick away perspiration.
Lurex® is a metallic fibre used in clothing embellishment.

PREPARATIN FOR DYEING ACRYLIC FIBRES

Preparing the material:

Poor preparation of the goods is usually the major cause of poor quality dyeing and preparation should be of the highest quality consistent with the final price of the material. The preparation of acrylic fiber materials may involve desiring of woven materials, scouring and bleaching. Combined desiring and scouring are often possible since relatively soluble sizing materials such as modified starch.

Polyvinyl alcohol is normally used. Scouring with weakly alkaline solutions of ammonia or presidium pyrophosphate (Na3HP207) is common. A non-ionic detergent is essential. Cationic auxiliary products may have substantively for the anionic groups in the fibers and block dyeing sites whereas residues of anionic product will interact with and even precipitate the cationic dyes in the bath.
Acrylic materials sometimes have a slight yellow cast, usually a sign that drying was too severe. Bleaching is possible with sodium chlorite (NaCIO2) and formic acid or brightening with a fluorescent whitening agent. Some fluorescent whitening agents can be used in the presence of sodium chlorite, allowing combination of the two methods. Stabilizers that control chlorine dioxide emission (Scheme 18.3), such as borax or polyphosphates should be used. A corrosion inhibitor such as sodium nitrate is essential when using steel equipment. Some cationic dyes are very sensitive to traces of chlorine and will rapidly fade giving poor colour yields, particularly when dyeing pale shades. An anti-chlor treatment of fabric bleached with sodium chlorite may be necessary and small additions of sodium bisulphate or thiosulphate to the dyebath will avoid problems with cationic dyes sensitive to traces of chlorine in municipal water.

                                   5ClO2- + 2H+ = 4ClO2 + Cl- + 2HO-

Dyebath preparation:The dye powder is usually pasted with acetic acid and then mixed with boiling water. Cationic dyes with delocalized cationic charges are intensely coloured and it is essential to avoid dust escaping from the powders. Concentrated liquid dyes avoid this problem. Solid forms of these dyes are often not easy to dissolve because of their tendency to form gummy material. Preparation of a paste with methanol and addition of warm or hot water is sometimes a useful alternative. Some cationic dyes are not stable in boiling water. Many react with alkali to give colorless products such as the free amine from neutralization of an ammonium ion group (reverse of Scheme 18.1), or a carbine by reaction of the cationic group with hydroxide ion (Scheme 18.4). Dyeing with cationic dyes therefore invariably takes place in weakly acidic solution to avoid these problems.

                                      Dye+(aq) + HO- (aq) = Dye-OH(s)

Dyeing procedure:Acrylic fibers may contain a variety of different anionic groups. These include a limited number of terminal sulphate and sulphonate groups arising from the persulphate polymerization initiator (Figure 3.2). In other types there may be appreciable numbers of carboxyl ate groups from acrylic acid or similar commodores added to the acrylonitrile before polymerization (Section 4.4.1). These anionic groups are responsible for the substantively of cationic dyes for such fibers. Figure 18.2 compares equilibrium dye adsorption as a function of Ph for two types of acrylic fibres (A and B). Dyeing acrylic fibres with cationic dyes is carried
Equilibrium dye adsorption by acrylic fibres with only sulphate and sulphonate end groups (a) and with carboxyl ate group (b) Out in weekly acidic solution containing acetic acid and sodium acetate and a non ionic wetting agent and dispersant. A small amount of sequestrate ensures that heavy metals do not interfere with chemicals in the solution.The dye solution is often prepared by pasting with acetic acid, and a stable Ph OF 4.5 5.5 can be obtained by addition of sodium acetate to buffer the solution. Dyeing at around Ph 5 suppressed the dissociation of any carboxylic acid groups in the fibre and thus controls the dyeing rate. Note the increased dye uptake of the acrylic fibre with carboxylic acid groups (b) in figure 18.2) as the acid groups dissociate and become anionic above pH 6. The number of carboxylare groups in an acrylic fibre varies from one type to the next. Level dyeing requires strict control of the pof cationic retarding agents. The latter initially block the anionic sites in the fibre and are gradually replaced by the more. An addition of up to 2.5 g 1-1 of anhydrous sodium sulphate helps to offset the negative surface charge and sodium ions weakly block anionic sites in the fibre. Both effects decrease the initial rate of dye absorption. Sodium sulphate is not as effective as cationic retarding agents that have some substantively for the fiber. shows a typical dyeing procedure. If dye additions are needed to give the correct shade, the bath temperature is first slowly reduced to below 80 c Acrylic materials are quite thermoplastic. They easily form crack marks and creases and textures acrylic filaments also readily lose their characteristic Bulk.

After dyeing is complete, the bath is slowly cooled to 50-60 C to avoid these problems. Rapid cooling by addition of cold water to the dyebath cab can be disastrous as it causes immediate setting of creases in the goods. The material is finally rinsed and possibly given a mild scour with a non-ionic detergent and a little acetic acid plus a softening agent.

Problems in dyeing acrylic fibers with cationic dyes :

1. Cationic dyes rapidly adsorb on all available surface of the acrylic fibres because of the polymer’s negative surface potential in water, Once the fibre surfaces are saturated the rate of isothermal dyeing is inedependent of the bath concentration and of the lliquor ratio since the rate of diffusion of dye into the fibre is slow.
 
2. Addition of sodium supphate to the dyebath suppresses the rapid strike as sodium ions counteract the negative charge on the fiber surface. Above the dyeing transition temperature (TD) under the actual dyeing conditions, cationic dyes tend to exhaust very rapidly over a small range in temperature. Great care is needed at temperatures just above TD to avoid unlevel dyeing. The rate of diffusion of the cationic dyes into the acrylic fibre is very slow below TD because of the absence of the required polymer chain mobility. The rate of dyeing increases rapidly above TD and cab double for every 2.5-3.0 C increase in rapidly above TD and double for every 2.5-3.0 C increase in temperature. The corresponding increases in temperature needed to double the dyeing rates of nylon and polyester are typically 10 and 5 C respectively, but at higher temperatures for polyester. Once the acrylic fibre becomes accessible very careful temperature control is required. For this reason, once the bath tempetature reaches 70-75 C, the rate of heating Is usually significantly decreased .The careful temperature control required when dyeing acrylic fibres with cationic dyes is necessary to avoid unlevel dyeings. These dyes on acrylic materials have at best poor migration ability. Some newer types of more hydrophilic cationic dyes have low molecular weights and lower substantively. They migrate move readily but attempted leveling by extended heating or heating to a higher dyeing temperature is dangerous because of the thermo plasticity of the fibre.

If the acrylic fiber has a significant number of carboxylate groups present, the dyeing Ph will greatly influence the dyeing rate. The rate of exhaustion will increase with increase in the Ph as more carboxylic acid groups dissociate. Thus it is important to know the characteristics of the particular acrylic polymer in advance.

Enzyme Washing in Textile

Enzyme washing is a laundering processes which uses enzymes to clean clothing or to finish fabric, especially in the case of jeans and other garments with a worn-in look. Various enzymatic cleaners are available from stores which specialize in laundry supplies, and can also be special ordered. For regular cleaning, enzymes carry numerous economic and environmental benefits. On an industrial scale, enzyme washing has replaced laborious laundering techniques such as stonewashing, saving money and environmental impact for companies.
Enzymes are proteins produced by living organisms. All organisms produce a wide range of enzymes to accomplish necessary biological tasks. Some enzymes can also be replicated in the lab, or engineered to perform in a particular way. One of the reasons that enzyme washing is so ecologically friendly is the natural origins of enzymes, which biodegrade, rather than lingering in the water supply. Enzyme washing products are also much more potent than other laundry products, requiring people to use far less, in terms of volume.
Different types of enzymes are suitable for different stains. In all cases, the enzyme washing process breaks the stain down into smaller molecules which can be removed with water or conventional soap. Amylases will remove starch based laundry stains, while proteases break down protein chains, making them suitable for protein stains. Lipases work very well on grease and oil, and cellulases are excellent general cleaners. Enzyme washing also yields a softer, more supple garment.
For delicate garments, enzyme washing can be an excellent way to get clothing fresh and clean. Enzymes also work at very low temperatures, making them suitable for cold wash only things ranging from silk to wet suits. Many natural detergent products mix enzymes into their formulas, to ensure that they are effective at all temperatures and on all stains.
Commercial clothing manufacturers also use enzyme washing to make their clothing appear aged and worn, especially in the case of jeans. Cellulases are usually used, since they will loosen the indigo dye in the denim, making the jeans look broken in and used. The enzymes will not compromise the strength of the fabric, but they will make the jeans softer, more supple, and more neutral in odor. Unlike stonewashing, the process used to make jeans appear beaten up and worn before enzyme washing, enzyme washing will not leave residue in drains and on clothing. These enzyme washed garments may have labels indicating that they were subjected to the enzyme washing process before shipment and sale.

Jeans Fabric in Faison

History

Jeans fabric was made in Chieri, a town near Turin (Italy), in the 1600s. It was sold through the harbour of Genoa, which was the capital of an independent republic, and a naval power. The first were made for the Genoese Navy because it required all-purpose pants for its sailors that could be worn wet or dry, and whose legs could easily be rolled up to wear while swabbing the deck. These jeans would be laundered by dragging them in large mesh nets behind the ship, and the sea water would bleach them white. According to many people the jeans name comes from bleu de Gênes, i.e., blue of Genoa[citation needed]. The raw material originally came from the city of Nîmes (France) Serge de Nîmes i.e. denim.

Riveted jeans

A German-Jewish dry goods merchant Levi Strauss was selling blue jeans under the "Levi's" name to the mining communities of California in the 1850s. One of Strauss's customers was Jacob Davis, a tailor who frequently purchased bolts of cloth from the Levi Strauss & Co wholesale house. After one of Davis's customers kept purchasing cloth to reinforce torn pants, he had an idea to use copper rivets to reinforce the points of strain, such as on the pocket corners and at the top of the button fly. Davis did not have the required money to purchase a patent, so he wrote to Strauss suggesting that they both go into business together. After Strauss accepted Davis's offer, the two men received U.S. Patent 139,121 , for an "Improvement in Fastening Pocket-Openings," on May 20, 1873.
In 1885 jeans could be purchased for $1.50. Today, some jeans cost $200 to $500 with limited-edition and collectibles costing up to $2000.

Jeans in popular culture
Blue jeans

Copper rivets for reinforcing pockets are a characteristic feature of blue jeans.
Initially, blue jeans were simply sturdy trousers worn by workers, especially in the factories during World War II. During this period, men's jeans had the zipper down the front, whereas women's jeans had the zipper down the right side. By the 1960s, both men's and women's jeans had the zipper down the front. In the United States during the 1950s, wearing of blue jeans by teenagers and young adults became symbolic of mild protest against conformity. This was considered by some older adults as disruptive; for example, some movie theaters and restaurants refused to admit patrons who wore blue jeans. During the 1960s the wearing of blue jeans became more acceptable and by the 1970s had become general fashion in the United States, at least for informal wear. Notably, in the mid-1950s the denim and textiles industry was revolutionized by the introduction of the stone-washing technique by GWG (Great Western Garment Co.). Entrepreneur, importer, and noted eccentric Donald Freeland of Edmonton, Alberta pioneered the method, which helped to bring denim to a larger and more versatile market. Denim suddenly became an attractive product for all age groups and Freeland became one of the most important innovators in the history of denim and denim products. It should be noted, also, that Freeland contributed to a variety of other denim textile developments throughout his career with Great Western Garments (GWG)[1] Acceptance of jeans continued through the 1980s and 1990s to the point where jeans are now a wardrobe staple, with the average North American owning seven pairs.

As imported American products, jeans were somewhat expensive, especially in the case of the Soviet Union which restricted hard currency imports. In Spain they are known as vaqueros or "cowboys," in Danish cowboybukser meaning "cowboy pants" and in Chinese niuzaiku (SC), literally, "cowboy pants" (trousers), indicating their association with the American West, cowboy culture, and outdoors work. Similarly, the Hungarian name for jeans is "farmernadrág", meaning "farmer-trousers".

Jeans can be worn very loose in a manner that completely conceals the shape of the wearer's lower body, or they can be snugly fitting and accentuate the body. Historic photographs indicate that in the decades before they became a staple of fashion, jeans generally fit quite loosely, much like a pair of bib overalls without the bib. Indeed, until 1960, Levi Strauss denominated its flagship product "waist overalls" rather than "jeans".

Blue jean insulation

Recycled blue jean is becoming a popular insulation material (sometimes called Cotton Batt insulation) used in the construction of houses. Due to its low relative synthetic chemical composition and because it is made of recycled materials, it is gaining prominence in green building circles. Like conventional insulation, it moderates heat transfer and reduces sound transfer between floors or rooms. Blue Jean insulation has an R-Value of 13 to 19 (for 3.5 and 5.5 inch batts, respectively) making it a preferable insulator to typical fiberglass batts even without taking into account the environmental considerations.

Fits

Fits of jeans are determined by current styles, sex, and by the manufacturer. Here are some of the fits produced for jeans:
Ankle jeans
Baggy jeans
Bell-bottoms/Flares/Bootcut
Boy cut
Carpenter jeans
Hip-huggers/Low-rise jeans
Capris
Overalls
Phat pants
Relaxed Fit/Loose
Sagging
Skinny jeans
Straight jeans
Jorts (Jean shorts)
Boot cut

Jeans come in many styles and fits based on the manufacturer; some of the more popular brands include Lee's, Levis, Urban Pipeline, Unionbay, NoBoundaries, and Wranglers. The styles popular of teenagers include yellow and white fades to look as if they have been worn down and been worked in. Some brands even sell vintage looks where the legs are pre-scrathed and torn before use.

Rises in jeans (the distance from the crotch to the waistband) range from high-waisted to superlow-rise (Low rise can be called Low Riders). Jeans for men usually have a longer rise and zipper, whereas women have a shorter rise and zipper, although exceptions do exist and this is largely a function of current trends. In decades past, when high-waisted jeans were popular, it was often the women's that featured a longer rise.

Stone Washing of Jeans

Stone washing is a textiles manufacturing process typically utilized by the fashion industry, in order to give a newly-assembled cloth garments a worn-out appearance. Stone-washing also helps to increase the softness and flexibility of otherwise stiff and rigid fabrics such as canvas and denim.
The process does literally use large stones to roughen up the fabric being processed. The garments are placed in a large horizontal industrial clothes washer that is also filled with large rocks. As the wash cylinder rotates, the cloth fibers are repeatedly pounded and beaten as the tumbling stones ride up the paddles inside the drum and fall back down onto the fabric.
Stone washing is similar in operation to a ball mill, except that this is a wet process.

Stonewashed jeans
Stonewashed jeans are jeans that have been treated to produce a faded, worn appearance. This is usually accomplished either by washing the jeans with pumice in a rotating drum, or by using chemicals to create the appearance without the use of a rotating drum. Stonewashed jeans were a popular fashion trend in the 1990s.

Jeans

This article is about the type of clothing. For the 1997 Indian film, see Jeans (film).

Denim Jeans

Jeans are pants made from denim. Mainly designed for work, they became popular among teenagers starting in the 1950s. Historic brands include Levi's and Wrangler. Today, jeans are a very popular form of casual dress around the world and come in many styles and colors, with the "blue jeans" particularly identified with the American culture, especially the American Old West. Americans spent more than $14 billion on jeans in 2004.

Disperse Dye

Introduction: 
Dyeing of natural fibers such as cotton, wool, silk etc, which are hydrophilic in nature, are done by direct, acid, vat, sulphur etc. Dyes which are water soluble or made soluble by reduction. When hydrophobic fibers made their appearance, soon after first world war, faced a problem in dyeing as the ─OH group has been blocked by ─COOCH3 group. Therefore affinity for dyes has been checked. Scientists took attemps of creating new dyes and developed acetate dyes or disperse dye. The term disperse dyes means free from ionizing groups, low water solubility and are suitable for dyeing hydrophobic fibers from colloidal dispersion.

What is Disperse Dye: 

A dye that is almost totally insoluble in water. Disperse dye exist in the dye bath as a suspension or dispersion of microscopic particles, with only a tiny amount in true solution at any time. They are the only dyes that are effective for “Normal” polyester. Some types are used for Nylon and Acetate. Polyester is dyed with disperse dyes by boiling with carrier chemicals or by heating the liquor to about 130°C which requires elevated pressure (Like a pressure cooker), Therm sol dyeing,
Where the fabric is padded with dye liquor then dried and heated to about 200°C for about 90 seconds, is also used for polyester and for coloring the polyester component of polycotton blends. Disperse dyes are also used for sublimation printing of synthetic fibres and are the colorant used in crayons and inks sold for making “Iron-ON” transfers.
The first dyes for cellulose acetate fibres were water soluble. The dye molecules contained a methylamino sulphonate group (-NHCH2SO3Na) introduced by reaction of a primary amino group with formaldehyde and sodium bisulphate (Ionamine dyes, 1922). During dyeing, this group hydrolysed to the less soluble parent amine (on figure-01).

Dye-NH-CH2SO3Na (aq) + H2O → Dye-NH2(s) + CH2O(aq) + NaHSO3(aq)

Figure-01

It was soon recognized that it was this compound that the cellulose acetate absorbed. The first true disperse dyes were simple, relatively insoluble azo and anthraquinone compounds dispersed in water using the sodium salt of sulphated ricinoleic acid (on figure-02).

Dye(s) ↔ Dye (aq) ↔ Dye(fiber)
 

Figure-02

Many of these dyes are obsolete but their development provided the technology for preparing fine aqueous dispersions by grinding the dye with dispersing agents. A fine dispersion is essential for rapid dyeing and avoids deposition of larger dye particles on the material.

Classification of Disperse dye for Polyester:

Disperse dyes for a compound shade on polyester can have quite incompatible dyeing properties. The SDC classification of disperse dyes is based on migration ability during exhaust dyeing, colour build-up, sensitivity to changes in temperature and the rate of dyeing.

This type of dye is often classified on the basis of dyeing rate and sublimation fastness, particularly for polyester dyeing. These two properties are a function of molecular weight and the number of polar groups in the dye molecule. The most common classifying is given bellow :

01.Low energy.

02.Medium energy.

03.High energy.

1. Low Energy Disperse Dye: 
Most dyeing and fastness properties change gradually with increase in molecular size. Small dye molecules with low polarity are leveling, rapid dyeing dyes with poor heat resistance. These are called low energy disperse dye.

2. Medium Energy Disperse Dye: 
Most of the dyeing and fastness properties change gradually with increase in molecular size. Moderate dye molecules with moderate polarity are leveling, rapid dyeing dyes with moderate heat resistance. These are called medium energy disperse dye.

3. High Energy Disperse Dye: 
More polar, higher molecular weight dye has low dyeing rates, poor migration during dyeing but good heat and sublimation fastness. These constitute the high energy disperse dye.

Selection Properties: 

 Disperse dyes have some general properties which are given bellow –

· Solubility: Disperse dyes are insoluble in water or slightly soluble in water. It makes fine dispersion with water with water with dispersing agent. Dissolves in organic solvents like benzene, toluene etc.

· Fastness to washing: The fabric dyes with disperse dyes shows moderate to good washing fastness.
· Light Fastness: Most of the disperse are very fast to washing. The minimum light fastness rating is 4-5.
· Sublime ability: Due to stable electronic arrangement disperse dyes have good sublime ability.
· Gas Fading: Fabrics dyed with certn blue & violet disperse dyes conaining anthraquinone structure become fade in presence of nitrous oxide. This nitrous oxide may be made in nature from various sources such as open gas fire, electric heating arrangement.

Commercial (Trade name) Name of Disperse Dyes:  
· Terasil.
· Foron.
· Palanil.
· Resolin.
· Samaron.
· Dispersol .

Dispersing Agent:
The actual disperse dye is formed as relatively large particles and in this form it is unsuitable for application on hydrophobic fibers. If these big particles are used in dyeing as such, they produce uneven and specky dyeing and their full colour value is not realized. In order to ensure uniform dyeing, the dye should be present in the dye bath in a uniform and very fine form, which should be stable under dyeing condition. This requires a large amount of suitable dispersing agents followed by grinding. The dispersing agent should be effective under the dyeing conditions and should be stable to hard water, high temperature and other dyeing assistants.
Soap powder, Turkey Red Oil, Alkylsulphates, Alkylarylsulphonates, Fatty Alcholethylene Oxide condensates, Naphthalene-β-sulphonate and formaldehyte etc are the recommended dispersing agent performs many functions. It assists the process of particle size reduction of the dye. It also enables the dye to be formed in the powder form. When the powder is added to the dye bath, it facilitates the recon version of the powder in to a dispersion, it is required for carrying out the dyeing. Finally, it maintains the dispersion in a fine form in the dye bath throughout the dyeing process. Dispersing agents increase the solubility of the disperse dye in water. It is seen that solubility of the dye in water is considerably increased by the dispersing agent and that different dispersing agents affect the solubility to different extents. It can be noted that the dyeing rate increase with increasing solubility the dyeing rate actually decreases.
Where the solubility is very high as in the case of direct dyes, practically no dyeing takes place.

 Commercial (Trade name) Name of Dispersing agent: 
1. Setamol -BASF.
2. Edalon -Sandoz.
3. Calsolene Oil HS –A.C.I.
4. Hipogal –Hoechst.

Commercial (Trade name) Name of Carrier:

1. Tumescal –A.C.I.
2. Matexil –A.C.I.
3. Levagol –Bayer.
4. Dilatin –Sandoz.
5. Invalon –Ciba.
6. Hisogal –Hoechst.
  

Method of the Dyeing Synthetic fibres with Disperse Dyes:There are three common method of dyeing with disperse dyes which are as follows:-

1. Carrier method of dyeing.
2. High temperature dyeing.
3. The thermosol process of dyeing.

1. Carrier method of dyeing:Polyester shrinks about 7% in boiling water and even more at higher temperature. To avoid this it is heat set. As a general rule it can be stated that a material (Synthetic) will be dimensionally stable if set at a temperature 30°-40°C higher than that to which it will been subjected during use. Fabrics are usually heat-set on pin stenters over temperature ranges 180°C and 200°C but garments can be set in steam autoclave machines at steam pressures between 20-25 pcs (pound per square inch). Terylene is highly crystalline and highly hydrophobic.
Therefore, dyes with large molecules can not easily penetrate in to this fibre. It has no chemically active group and can not combine with dye anions and cat ions. In practice, polyester fibres are dyed with disperse dye.
A considerable advance in the dyeing of polyester fibres was made when the carrier method was introduced. It was discovered that quite a number of organic compounds such as phenols, amines or aromatic hydrocarbons, when either dissolved or suspended in the dye bath, accelerated the absorption of disperse dyes by the fibre. The way in which carriers produce the effect is not clearly understood but they do cause some swelling of the fibre. It seems that they can enter into the fine structure of the polyester and push adjacent long-chain molecules apart. This loosens up the molecular pattern and facilitates the entry of the large dyestuff molecules. The water insoluble carriers also appear to from a surface film on the fibre in which the disperse dye is highly soluble. The transfer of dye, in such circumstances, does not take place between the aqueous phase and the fibre but between dyestuff dissolved in the carrier and fibre.
But it is found that there is a maximum concentration of the carrier above which the take-up of the dye by the fibre decreases. This optimum carrier concentration corresponds approximately with the amount necessary to saturate both fibre and dye bath phase of the system. Excess will introduce a third phase, namely undissolved carrier, which will compete with the fibre for the dye.
Two carriers which have proved success are diphenyl (Matexil CA-DP) and O-Pheny Pheny (Matexil CA-OPE). Diphenyl is a cream-coloured powder, insoluble in water, but in a readily- dispersable stat. Mateil CA-DP is a disphenyl carrier supplied in self-emulsifiable flakes. The emulsion i9s prepared by stirring the flakes into water at 80°C or hooter than this if desired and added to the dye bath at 60°C. The recommended concentration of carrier in the dye bath is 4 to 6 parts per liter. Matexil CA-OPE shouldbe used in the dye bath as 7.5 parts per litter and is added directly to the dye bath at 50°C t o 60°C.
The addition of dispersing agent should precede that of Matexil CA-OPE. There are many other carriers which can be used in the carrier dyeing methods. A typical recipe of carrier dyeing is given bellow:

Recipe:

Dyestuff – 3% (20-30g/liter) on the weight of material
Carrier – 15g/liter
Dispersing Agent – 2 to 3g/liter
Acetic Acid – 5cc/liter
Material liquor Ratio – 1:20
Temp – Boil
Time – 1hour to 1.5 hour

The dye bath is made up with 1/2 - 2 kg (.5 – 1g/liter) of an anionic surface active agent and 3-4kg carrier per 1000 liters. The temperature should be 40°C and after dye has been added, the liquor is slowly brought up to 100°C. After 15 minutes at this temp 5cc acetic acid is added. Boiling is continued for a further 1 hr after the addition of acetic acid. After dyeing the goods are washed out with a detergent and some NaOH to ensure the complete removal of carrier.

2. High temperature dyeing:There are many advantages associated with dyeing polyester at temperature range between 120°C and 130°C. Heavy shade can be dyed pleated because of the permanency of the crease so formed. When dyeing at atmospheric pressure, only dyes of low molecular weight which tends to sublime during pleating can be used, the more satisfactory colours with higher molecular weights can be applied at 120°C -130°C. There is no perceptible loss of elasticity or tensile strength when polyester fibres are dyed under neutral or slightly acid conditions at 130°C. But if any alkali is used there is degradation in strength and elasticity. Any alkali used in scouring must be removed entirely before high temperature dyeing. The fibre should be heat-set before dyeing.

The following disperse dyes are recommended for high temperature dyeing:
C.I Disperse Yellow 1, 39
C.I Disperse Orange 13
C.I Disperse Red 11, 13
C.I Disperse Violet 26
C.I Disperse Blue 26 

The dye bath is made up with dyestuff, dispersing agent (Matexil DN-VI) or some similar product which is stable up to 130°C.
 

The dyeing should be started at 70°C, the temperature raised slowly to 120°C-130°C and maintained for a period of 30-60 minutes. When very heavy shades have been dyed it may be necessary to give a “Reduction Clearing” to avoid lack of fastness to rubbing. The goods are treated for 20 minutes at 45°C-50°C with 6kg NaOH(68), 2kg Na2S2O4 and 2kg Matexil Sc-A50 per 1000kg of water. Owing to the hydrophobic nature of polyester fibre only, surface dye will be reduced and the chemicals will not penetrate to react with the absorbed colour. After high temperature dyeing the goods should always have a final wash-off at 70°C for 15-20 minutes with suitable detergent.

 3. The thermosol process of dyeing:This dyeing process is not suitable for garments dyeing, Because of it is Unhygienic. 

The Problem of Dyeing Polyester: 
Polyester fibres are essentially undyeable bellow 70-80C, leaving only a 20-30C range for increasing the dyeing rate before recharging the boiling temperature. At any temperature, the rate of dyeing of polyester with a given disperse dye is very much lower than for cellulose acetate or nylon fibres.
 
The rate of diffusion of disperse dyes into the polyester bellow 100C is so low than that dyeing at the boil does not give reasonable exhaustion.
 
The rate of dyeing is higher for dyes of small molecular size that have higher diffusion coefficients. Dyeing is faster when using fibre swelling agent called carriers to improve the fibre accessibility, or when dyeing at higher temperatures above 100C increase the dye diffusion rate. Fibres of the most common polyester, polyethylene terephthalate (PET or PES), are quite crystalline and very hydrophobic. Hot water does not swell them and large dye molecules do not easily penetrate into the fibre interior. Polyesters have no ionic groups and are dyed almost exclusively with disperse dye. The better diffusion at the boil of low molecular weight dyes results in moderate migration during dyeing dyeing but then the washing fastness is only fair. Many of the more recent disperse dyes are specifically for dyeing polyester. These are of higher molecular weight to provide adequate fastness to sublimation during heat treatments. Some of these produce a reasonable depth of shade by dyeing at the boil. Most, however, require higher dyeing temperatures or carriers for satisfactory results. Dyeing of polyester with disperse dyes have good light fastness. This does not always correlate with the light fastness on other fibres such as cellulose diacetate.
 
The disperse dyes provide a full range of colours with adequate to good build-up on PET fibres.
Uneven filament texturising or heat setting can lead to barre but higher dyeing temperatures, or addition of some carrier, will promote migration to minimize this, Again, a full black requires aftertreatment of the dyeing by diazotization of an amino disperse dye and cupling with a suitable component, often BON acid. Concurrent dyeing with a mixture of the amino disperses dye and dispersed BON acid, followed by treatment with sodium nitrate and hydrochloric acid, is a common procedure. Some blacks are mixtures of dull yellow, red and blue dyes.