Knitted Fabric Manufacturing -...

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Knitted Fabric

Manufacturing

Side Interlock Rib knit Jersey

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Lecture 01

Course Introduction

� Course Outline

� To give an understanding to participants about

knitting technology and its management.

� This course will cover history of knitting and most

modern development in knitting technology.

� Participants will be made familiar with the knitting

manufacturing systems and its managements.

Expected Outcome

� Participants will be able to understand one of

the most important fabric formation process

and this would also help understanding

forthcoming courses of textile e.g. wet

processing and garment manufacturing etc.

Course Material

� Books: Knitting Technology David J Spencer

� Notes prepared by Mushtaq Mangat

� Class notes

� Hand-outs

� Survey of the industry

� Interviews of industry leaders

� Net Surfing

Attendance Policy

� Five classes missing means “Grade F”

� Five minutes late means no entrance in class

� Have to justify five minutes late

� We will start class at exact time INSHALLAH

Missing of one class means losing one mark

Grade Policy

� Assignments: 12.5%

� Quizzes: 12.5%

� Midterms: 20%

� Project 15%

� Attendance: 10%

� Final: 35%

Lecture 02

� Knitting History

Fabric Formation Process

Conversion of fibers into a sheet, which should have following properties:

� Strength to bear stretch and stress

� A determined surface area

� Dimensional stability

� Elasticity

� Holding capacity to liquid or solid

� Able to be used for any particular purpose

Fabric Formation Techniques

� Weaving Woven fabric

� Knotting Nets

� Knitting Hosiery fabric

� Bonding Namda (a sheet used by

nomads)

� Tufting Carpet manufacturing

Lecture 02

Knitting History

From Hand Knitting to Computerized

Knitting Machines

Knitting Start

� The art of hand knitting has been practiced since thousands of years.

� How this art was learnt by ancient human is still a mystery and so is the country and time of its origin.

� However, some believe that this art originated in Persia. Others claim Israel, Jordan and Syria belt as its origin, and still others claim mountains of North Africa.

� Knitted socks discovered in Egyptian tombs have been dated between the 3rd and 6th centuries BC.

Ancient Times and Knitting

� Job of ladies

� Pastime hobby

� For safety and decoration

� Popular where temperature was generally low

� For specific parts of body, like, hands, feet,

head, face not for main body

Starting of New Knitting Era

� In the medieval Europe hand knitting was an

important industry and had developed into an

advanced craft by 16th century

Hand Knitting in England

� Hand knitting in England expanded as an industry in Tudor times (1485-1603). Knitted caps and stockings were highly fashionable. From the time of Henry VIII, fine knitted silk stockings imported from Spain were part of court fashion.

� Previously, a piece of cloth was cut to the shape of a leg and the edges sewn together to create a stocking. By the time of Elizabeth I, knowledge of how to hand knit stockings had spread around England and documents refer to the industry in places as far apart as London, Kingston (Surrey), and Richmond (Yorkshire

William Lee and Knitting

� In 1589, William Lee, a clergyman invented the first knitting machine in England.

� After this invention, in the 17th and 18th centuries the art of knitting was gradually taken over by guild organized cottage industry.

� Interestingly, the basic technology of the modern day knitting machines is similar to Lee's machine.

� Even the full-fashioned machine invented in 1864 by William Cotton of Leicestershire, England used the same bearded-spring needle, which was part of the original model of Lee.

The foundation of the knitting

industry

� Investing in frames

� During the early seventeenth century, knitting frames remained an expensive investment and few were built. Even in the 1660s, frames could cost as much as £20 to £30 each, more than a worker's yearly wage. The hand knitters did not have to pay such high costs and could knit as long as they had a pair of knitting needles. Demand for the output of hand knitters and framework knitters allowed both branches to expand during the two centuries after Lee's invention.

Changing products

� New technology

� In the second half of the eighteenth century there were a number of advances in the development and use of knitting-frame technology. These followed on from Jedediah Strutt's patent for his Derby Rib machine in 1758, which created a more elastic fabric. Hose made using this type of fabric soon became more popular than hand-knitted stockings. With money to be made from successful inventions, many individuals invested time and money in experimenting with new adaptations and patterns

� Transition to factory production

� Working at home

� Framework knitting was traditionally carried out in

workers' homes. Hosiers supplied yarn to the

workers, children commonly wound the yarn onto

bobbins, men knitted it into stockings and women

seamed and embroidered the stockings. The industry could keep the whole family occupied

Knitting and 19th Century

� In the 19th century power was applied to the knitting

machines and simultaneously circular-knitting

machines appeared on the scene.

� Women's stocking when knitted on original machines were a straight knitted tube, because stitches could

not be added or dropped on circular knitting machine.

So these products were known as hosiery.

� The word hosiery is derived from the old English

hose, which means a covering for the leg. Now

seamless stockings are knitted even on circular

machines, developed in the mid-19th century.

� To start with cotton, wool, silk and later rayon yarns

were used for making hosiery, but with the emergence of nylon in the 1940s women preferred

nylon hose, because they could be permanently

formed into the desired shape by heating. The use of

nylon also improved the fit of hosiery due to stretch

ability of nylon fabrics

� Subsequently, in Great Britain, hosiery came to be

associated with all types of machine-knit garments,

now called knitwear. In United States they still call

stockings, socks, panty hose, and tights as hosiery

products.

� Between 1880 to 1910 knitwear was mainly a female

fashion, later knitted pullovers, cardigans, skirts,

men's underwear, sportswear and swimwear became

popular.

� Developments in the 20th century increased the

production speeds of the machines and offered wider

choice to pattern the knitted fabrics.

� Now computer controlled knitting machines have

come on the scene, which are highly versatile.

Knitted garments have now become every day dress.

Knitting in 20th century

Workshop of the world

� A resourceful Britain

� Between 1840 and 1860 Britain experienced a period of rapid growth that saw many changes in the workplace and in society. The rail network in Britain expanded to around 10,000 miles of track, cutting travel times between many cities and towns. For the first time in history, goods could be transported across the country within a matter of hours. Opportunities for business opened up and the economy boomed. The construction of the railways alone employed 200,000 people and at its peak used 40% of the country's expanding output of iron

Seamless improvements

� The circular knitted stocking was technologically improved by the use of nylon. The thermoplastic properties of nylon meant that when placed on a shaped board and heated the yarn softens, and permanently takes on the shape of the board when the heat is removed. Unlike steamed natural fibres, heated nylon stockings did not lose their shape when washed. Technology had reached the point where the quality of seamless stockings could rival fully-fashioned stockings

In Current Era

� We have:

� Circular knitting machines of high speed (plus

50 RPM) gauge more than 40, dia plus 50

inches. Feeders more than 200, fully garment

knitting machines, stripers, terry and many

thing more

Latest Developments in Knitting

� The art of knitting has come of age. From hand knitting to hand operated machines was a long way. Gradually it upgraded to power operated V-Bed and circular knitting, and then it leapfrogged to microprocessor controlled machines. Now lately CAD/CAM has revolutionised the knitting industry. However, in the developing countries including China, they still use manually operated flat and V-bed knitting machines for thier bulk production since cheap labour is available.

� Whole garment knitting

Lecture # 3

Significance of Knitting

Significance of Knitted Fabric

� Knitting Clothes---a modern way of living

Knitted Fabric Characteristics

� Flexibility

� Elasticity

� Adaptability

� Air permeability

� Crease resistance

� Hand feel

� Bulky

� Easy to wear

� Less size problems

� Price at the last

Change in life style

� More traveling

� More casual life style

� Shortage of time

� Busy life

� More work

� Fashion

� More colors and embellishments

Knitted Garments in new era

� Most popular dress

� Comfort and convenient

� Cheap and highly fashioned

� Fit for body

� Easy to produce

� Easy to make changes in designs

Lecture # 4

Knitted and woven fabric

evaluation

Woven and Knitted Fabric

Comparison

Each one is better than other

Areas where Woven and Knitted

Fabric differ

� Method of production

� Fabric properties

� Machine requirements

� Usages of fabric

� Price

� Style and fashion

Lecture # 5

woven and knitted fabric

Woven and Knitted

Fabric

Production Method

Woven

� Insertion of weft through warp

� Warping

� Sizing

� Beaming

� Bobbin winding

� Loom machine working

Knitted

� Direct supply of yarn to knitting needles � No warp in weft knitting and no weft in warp knitting

� No application of size

� No beaming in case of weft knitting

� Beaming process in case of warp knitting

� Very quick start of production

Properties

Woven Knitted

Stable Unstable

Rigid Flexible

Harsh feel Soft feel

Less shrinkage Highly shrinkage

Less adaptability Highly adaptability

Long procedure of

production

Very quick

production

Need machine Can be done with

needles manually

Need sizing No need of sizing

Costly process Cheap production

process

Difficult to make

designs

Easy to make

designs