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Cotton: from Grower to User 1Prepared by Effective ChangePty Ltd

Contents

Module Overview ....................................................................................................................... 2

Module Objective ....................................................................................................................... 2

Module Contents......................................................................................................................... 2

Learning Outcomes ..................................................................................................................... 3

Module Symbols.......................................................................................................................... 4

Unit 1: Introduction ............................................................................................................... 5

Unit 2: Cotton: Fundamentals and History ............................................................................. 7

Unit 3: Growing and Harvesting Cotton .............................................................................. 11

Unit 4: Cotton Processing .................................................................................................... 16

Unit 5: Cotton Properties and Varieties ............................................................................... 31

Unit 6: Cotton Counts and Yarns ......................................................................................... 35

Resource Material Introduction ................................................................................................ 39

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This Module provides participants with an introduction to the growing and harvesting of cotton;an overview of the processes necessary to convert the raw cotton into yarn suitable for weaving;

and, a working knowledge of cotton properties, qualities and grades in preparation for the next

Module on weaving.

The objectives of this Module are to provide participants with:

an understanding of cotton growing and harvesting an overview of the processes involved in converting seeded cotton to yarn in preparation for weaving a working knowledge of cotton properties, qualities and grades specifically in relation to the

cotton yarns used to manufacture towelling products

This Module comprises these sections:

Introduction Introductions and Course Outline Introduction to Module 1

Cotton: Fundamentals and History What is Cotton? Fundamentals of Cotton Cotton Fibre History of Cotton Growth in Cotton Production

Growing and Harvesting Cotton Growing Cotton Harvesting Cotton

Cotton Processing Overview of Cotton Processing Ginning Classing and Baling Cleaning Carding Drawing Combing Roving Spinning

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Cotton Properties and Varieties Cotton Properties Cotton Varieties

Cotton Counts and Yarns Cotton Counts Cotton Yarns

At the completion of this module, participants should be able to:

Learning Outcome 1

Identify a key milestone for the Australian cotton industry

Learning Outcome 2

Identify the main cotton growing areas in Australia

Learning Outcome 3

List the key steps in the cotton growing cycle

Learning Outcome 4

Identify the differences between machine picking and hand picking

Learning Outcome 5State the purpose of ginning cotton

Learning Outcome 6

Identify the key reasons for cleaning cotton

Learning Outcome 7

Outline the steps in carding

Learning Outcome 8Explain the primary purpose of combing

Learning Outcome 9

Describe the differences between ring spun yarn and open end yarn

Learning Outcome 10

Describe the characteristics and properties of cotton that are most relevant to towelling products

Learning Outcome 11

Identify the main types of cotton used in towelling manufacture and describe the properties ofeach

Learning Outcome 12

Outline the two types of cotton count systems

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The following symbols in the text are designed to assist you to prepare and deliver your training:

Estimated time for activity, including PowerPoint slides and samples

PowerPoint Presentation Slide (PPS)

Note: PPSs are numbered by Module and Slide numbereg. PPS 1.6 is Module 1 Slide 6

Discuss

Sample

Handout

Note: Handouts are numbered by Module and Unit number

eg. Handout 2.3 is the Handout for Module 2 Unit 3

DVD

SHOW

SAMPLES

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Resource Material

The relevant resource material for this section is:

PPS 1.1: Cotton from Grower to User PPS 1.2: Overview of Module 1 Handout 1.1 Samples: Raw Cotton, Yarn CheeseAim

The aims of this section of the module are to provide participants with an:

introduction to Cotton from Grower to User opportunity to formally introduce themselves to each other overview of the contents of Module 1Timing

15 minutes

The estimated time for the Introduction is 15 minutes with 10 minutes for

Introductions and Course Outline and 5 minutes for Introduction to Module 1.

The information is primarily presented using PPSs.

Trainers Notes

Introductions and Course Outline

Welcome the participants and introduce yourself.

Ask the participants to introduce themselves and outline what their expectationsof the course are.

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PPS 1.1

Introduce the Cotton from Grower to User using the PPS:

Cotton from Grower to User

Module 1:COTTON

Introduction

Cotton: Fundamentals & History

Growing & Harvesting Cotton

Cotton Properties & Varieties

Cotton Counts & Yarns

Cotton Processing

Module 2:MANUFACTURING

Introduction

Yarn Preparation

Weaving

Drying

Finishing

Dyeing

Finished Product

Module 3:COLOUR &

DECORATING

Introduction

Colour Forecasting

Psychology of Colour

Colour Harmonies

Colour: FAQs

Discuss the assessment process.

Give participants Handout 1.1.

Introduction to Module 1

Show the participants the raw cotton and the yarn cheese samples.

Explain that the aim of Module 1 is to outline the process of converting raw cotton

to yarn that is suitable for weaving into towelling products.

PPS 1.2

Give an overview of the content of Module 1 using the PPS:

Overview of Module 1

Ginning Classing and Baling Cleaning

Carding Drawing

Combing Roving Spinning

History

of Cotton


Growing &

Harvesting CottonCotton Processing

Cotton Properties

& Varieties

Cotton Counts

& Yarns

SHOW

SAMPLES

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Resource Material

The relevant resources for this section are:

PPS 1.3: What is Cotton? PPS 1.4: Fundamentals of Cotton PPS 1.5: Cotton Fibre PPS 1.6: History of Cotton PPS 1.7: History of Cotton in Australia PPS 1.8: Growth in Cotton Production Handout 1.2Aim

The aims of this section of the module are to provide participants with an overview of the:

The fundamentals of cotton and cotton fibre history of cotton over the last 5,000 years key milestones in the cotton industry in Australia since 1788 growth of the cotton industry in Australia based on production of the raw materialTiming

8 minutes

The estimated time for Cotton: Fundamentals and History 8 minutes.

The information is primarily presented using PPSs.

Trainers Notes


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PPS 1.3

Explain cotton to participants using the PPS:

What is Cotton?

Cotton fibres are the seed hairs of the plantGossypium

Each fibre is formed by the elongation of a single cellfrom the surface of the seed

The word cotton is derived from its Arabic namepronounced kutan, qutn or qutan

Under a microscope, acotton fibre appears asa very fine, regular fibre,looking like a twistedribbon. These twists arecalled convolutions

PPS 1.4

Outline the fundamentals of cotton using the PPS:

Fundamentals of Cotton

Cotton is composed of long cellulosic molecules

It is typically around 88 96% cellulose. The rest is

protein, pectic substances, ash and wax

After scouring and bleaching, cotton is then about 99%

cellulose

The cellulosic wall of the cotton fibre give cotton its

unique characteristics: its crimp, wall thickness,

maturity, pliability, moisture absorbance andretainability

These characteristics contribute to making cotton the

most sought after natural fibre in the world

PPS 1.5

Outline the characteristics of cotton fibre using the PPS:

Cotton Fibre

The cotton fibre length varies with the

type and quality

It is stronger when wet

Cotton absorbs moisture readily, which

makes cotton clothes comfortable to

wear in warm weather (water retention of

50%, moisture regain of 7%)

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PPS 1.6

Outline the key milestone in the world history of cotton using the PPS:

History of Cotton

USA producing > 50% of worlds cotton1920s

Cotton gin invented1793

Cotton seeds arrive in Australia on First Fleet1788

Spinning Jenny invented in England1769

India produced fine quality cotton fabric.

Grown in the USA, China, Japan, Middle East

& Pakistan

3,000

years ago

Remnants found woven with feathers & fur5000

years ago

Background Information:

Cotton is one of the oldest known fibres It has been grown and used for more than 5,000 years Cotton was first cultivated in Pakistan Invention of the Spinning Jenny in England enabled cheap mass-production Invention of the Cotton Gin in the USA to remove the seeds from cotton fibrelead to further improvements in production

PPS 1.7

Outline the key milestones in the history of cotton in Australia using the PPS:

History of Cotton in Australia

Environmental audit and introduction of Best

Management Practices

1992

Cotton production increases as availability of

irrigation increases

1970s

First exportable surplus produced

Emerged as major crop

Cotton consistently profitable

1960s

Cotton industry all but non-existent1954

Australia fills gap caused by the US Civil War1861 >

Cotton seeds arrive on First Fleet1788

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PPS 1.8

Show the PPS on cotton production to demonstrate the growth of the cotton

industry in Australia:

Growth in Cotton Production

0

0.5

1

1.5

2

2.5

3

3.5

1980 1985 1992 1995 1997 1999

Millions of Bales

Background Information and Notes on PPS:

1830 3 bags of cotton were exported to England

1934 Production was 17,000 bales



1992 Production was about 2% of the worlds ginned cotton

1995 Production dropped due to drought

The Australian cotton industry:

is internationally competitive is increasingly efficient at processing cotton has a substantial share of its total production exported as cotton yarn, fabric or

finished product

Note to Trainer:

The following information is provided as background information only, should

any of the participants ask specific questions about genetically modified cotton.

Information on genetically modified cotton can be misunderstood andmisinterpreted so it is best not to raise the topic and only provide information if a

specific question is asked.

Genetically modified cotton actually reduces the need for fertilisers andpesticides because it is more pest resistance. Therefore it is better for the

environment and that is the focus of Australian research on genetically

modified cotton.

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Resource Material


PPS 1.9: Ideal Growing Conditions PPS 1.10: Cotton Growing in Australia PPS 1.11: The Cotton Cycle PPS 1:12: Harvesting: Machine Picking PPS 1.13: Harvesting: Hand Picking Handout 1.3 Sample: Seeded CottonAim

The aims of this section of the module are to provide participants with an overview of:

the growing cycle of cotton the types of machines used to harvest cotton machine harvesting versus hand pickingTiming

15 minutes

The estimated time for Growing and Harvesting Cotton is 15 minutes.

The information is presented using PPSs.

Trainers Notes


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Growing Cotton

PPS 1.9

Outline the environmental conditions needed to grow cotton using the PPS:

Ideal Growing Conditions

Cotton needs:

Warm, humid climate or a warm climate

with adequate irrigation

Long, frost-free period of 6-7 months

Mild temperatures

About 12 hours of sunlight per day

During the growing cycle 7.5cm12.5cm

of rain monthly or adequate irrigation


China is the leading producer of cotton world-wide Other major producers are the USA, the states of the former Soviet Union,

India, Pakistan, China, Brazil and Australia

PPS 1.10

Show the key cotton growing areas in Australia using the PPS:

Cotton Growing in Australia

Qld

NSW

Notes on PPS:

Cotton is primarily grown in central and north-western NSW and central andsouthern Queensland

Approximately 70% of Australias cotton is produced in NSW, with most of itbeing grown in the Murray-Darling Basin

The majority of cotton grown in Australia is irrigated cotton

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There are few areas in Australia suitable for non-irrigated or dryland cottongrowing

Hence most cotton is grown on land near major irrigation schemes and rivervalleys

PPS 1.11

Explain the cotton growing cycle using the PPS:

The Cotton Cycle

Cotton Seed

Planted

Open BollCotton Blossoms

Boll

Harvest 100 days

By end of 2nd day50 to 80

days

GROWING

SEASON

DAY 0

DAY

180

Notes on PPS:

From planting time to harvesting time is approximately 180 days or about 6

months

Day 1: Cotton seed is planted

Day 3-5: Seedlings appear

Day 100: Cotton blossoms

The cotton plants blossom over a period of time

and their yellowish/pink flowers bloom for 1 day

By the end of the 2ndday the flowers wither and

drop to reveal the formation of the boll or youngseed pod

Between Blossoming andMaturity:

Bolls grow and mature

It is during this time in the growing cycle that the

bolls need adequate rainfall or irrigation

Day 150 -180: Bolls open to reveal the white fluffy cotton

Each boll contains about 30 seeds and up to

500,000 fibres of cotton

Again the bolls do not all open together so the

picking season occurs over a period of time.

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In Australia most on-farm activities related to cotton growing occur in Australia

between August and May

August September: Soil PreparationSeptember October: Planting

November February: Growing Season

March May: Picking and Ginning


Cotton comes come from the Arabic word kutun which describes a finetextile

Cotton is a bushy plant that is a member of the Hibiscus familyShow the participants a sample of seeded cotton

Harvesting Cotton

PPS 1.12Harvesting: Machine Picking

Cotton is harvested by either a:

Cotton Picker: removes the cotton fromthe bolls without damaging the plant

Cotton Stripper: strips entire boll off the

plant

Australian cotton is harvested by pickers because the cotton

is cleaner

Notes on PPS:

Cotton pickers give much greater cleaning efficiency as the picker does notcollect as much trash, or unwanted twigs and leaves, as a cotton stripper.

Cotton that is cleaner when it is picked lessens the requirement for cleaning

during the ginning process

Machine picking of cotton allows mass harvestingBackground Information:

Australia, the USA and Israel are the only countries in the world to harvesttheir cotton exclusively with machines

SHOW

SAMPLES

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PPS 1.13

Outline the key points about hand picked cotton using the PPS:

Harvesting: Hand Picking

Hand picking cotton:

is slower than machine picking

better preserves fibre characteristics

leaves behind unwanted trash like

leaves and boll

selects fully grown cotton and leaves

young cotton for later picking

Show DVD

Note to Trainer:

Introduce DVD Reinforce key points

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Resource Material


PPS 1.14: Cotton Processing PPS 1.15: Ginning PPS 1.16: Classing & Baling PPS 1.17 & PPS 1.18: Cleaning PPS 1.19: Carding PPS 1.20: Drawing PPS 1.21: Combing: Lap Former PPS 1.22: Combing: Comber PPS 1.23: Combing: Grouping of the Combed Sliver PPS 1.24: Combing PPS 1.25 & PPS 1.26: Roving PPS 1.27: Spinning: Speed Frame PPS 1.28: Spinning PPS 1.29: Ring Spinning PPS 1.30: Winding PPS 1.31: Twisting PPS 1.32: Assembly Winding PPS 1.33: Open End Spinning PPS 1.34 & 1.35: Vortex Spinning PPS 1.36: Blending of Cotton with other Fibres PPS 1.37: Cotton Fibre Testing Handout 1.4 Samples: Ginned Cotton, Sliver Fibres, Seeded Cotton, Yarn CheeseAim

The aims of this section of the module are to provide participants with an overview of:

the stages involved in preparing cotton for spinning spinning cotton into yarn ready for weavingTiming

25 minutes

The estimated time for Cotton Processing is 25 minutes.

The information is presented using PPSs and samples of cotton at various stages of

processing and spinning.

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In a saw gin, circular saws grip fibres and pull them through narrow slotsleaving the seed behind. Saw gins are used with shorter fibres

Saw gins are primarily used in Australia because we grow more short staplelength cotton In a roller gin a rough roller grabs fibres and pulls them under a rotating bar

with gaps too small for seed. Roller gins are used with longer fibres

The by-products of ginning are:Lint:

Lint is the technical name for cotton fibre produced in the ginningprocess

Lint is used to produce cotton yarnMotes:

Mixture of trash like dirt, stalks, leaves and fibre The fibre can be used for lower grade cotton and paper but requires

further processing

Seed:

Seed contains linters or short, very fine fibres The cleaned seed is crushed to produce cotton seed oil and the

residue can be used for cattle feed. It may also be used as seeds to

plant again for the next cotton crop


The word gin in cotton gin is related to the word engine and means device. Itis unrelated to the alcoholic drink called gin!

55% of ginned cotton is made up of cottonseed, 35% is lint and 10% is trash. Cotton fibre waste has been used to clean up oil spills in the sea, as it soaks

up the oil well but the natural waxes that it contains help to keep the fibre

afloat.

Cotton trash such as left over sticks and leaves can be used as compost, and

put back into the soil.

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PPS 1.16

Outline classing and baling using the PPS:

Fibre is measured

against a set of

standards or

grades to

assesses quality

of ginning,

fineness and fibre

length.

Classing & Baling

Ginning Classing

Lint is pressed

into bales of a

standard size

Bailing

Notes on PPS:

Classing is the process of measuring the fibres against a set of standards or gradesThe lint is graded on a scale of 1 to 6, which assesses the quality of ginning,fineness and fibre length.

Raw fibre or lint is passed from the gin through pipes to a press The press compresses the lint into bales Each bale weighs 227 kg or 500 lbs, which is the standard Australian size. The

standard bale size for the rest of the world is 400 lbs.

A sample for classing is taken from every bale The bales are then sold to local spinning mills or overseas buyers or they are storedBackground Information:

A standard Australian bale of cotton makes approximately 500 light bath towelsShow the participants the sample of ginned cotton

SHOW

SAMPLES

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Cleaning

PPS 1.17

Explain the key reasons for cleaning the cotton lint using the PPS:

Cleaning

Ginning

Removes

Seeds

Lint & Trash

Ginning

Cleaned

Blended

Leaf

Stalk

Sand

Soil

Dust

Removes

40-70%

Trash

Notes on PPS:

Ginning removes seeds but not trash Trash is leaf, stalk, sand, soil and dust that is mixed in with the lint Lint needs to be opened, cleaned and blended to remove the trash

PPS 1.18

Explain the various stages of cleaning that occur in the blow room using the PPS:

CleaningBales

of Lint

Opening Blending Cleaning

CardingSeparator opencotton

Break it into small

tufts or flocks

Blow Room

Blend or mix fibresfrom different bales

together

Create uniformity of

staple and colour

Beatersprogressively open

cotton

Release trash

Lap

3-7 major cleaningpoints

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Carding

PPS 1.19

Outline the carding process using the PPS:

CardingCleaning

Blow Room

Opening &

Cleaning

Removes short fibres

Disentangles neps (knots)

Partially aligns fibres length wise

Blends fibres into web

Removes 80-90%

Dust & Impurities

Carding Machine

Lap

(long rollof cotton

SingleFibres

Drawing

Sliver (long,

loose strand

of cotton)Fibres

Notes on PPS:

Brushes, cleans, disentangles and straightens the cotton fibre All yarn is carded The sliver is output into cans for storageCompare the sliver sample to the seeded cotton sample to demonstrate that it isnow clean and looks more like a strand of cotton, ie. it is longer and finer.

Drawing

PPS 1.20

Outline the drawing process of converting a sliver to a finer yarn using the PPS:

Drawing

Sliver

Straightens and parallelises the fibres

Blend slivers to improve regularity of

weight, length

and fibre mix

Draw out slivers

to produce

slivers of

required weight

and length

Drawing

Carding Combing

Spinning

SHOW

SAMPLES

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Background Information and Notes on PPS:

The carded slivers are coiled in cylindrical cans with spring-loaded bases sothat there is no tension applied to the slivers when drawn out. In the sliver thecotton fibres are not parallel

The carded slivers then are passed through a drawing process:slivers are laid parallel in groups of 6 or 8 and passed through high-speedpressure rollersthe speeds of these rollers are varied so that the group of is "drawn" toform a single sliver

The slivers vary in thickness. Feeding slivers together is known as doublingand leads to an improvement in regularity in the sliver. When fed together thethick part of one sliver is offset by the thin part of another

This process improves the uniformity of the sliver because of the multipledoubling

Doubling feeds multiple slivers together and so it blends the fibres too Each succeeding pair of rollers runs faster than the preceding pair. The fibres

are gripped by a faster pair and drawn out from the preceding slower pair

The action of reducing the thickness of the feed sliver (input) by drawing isknown as drafting

The operation of doubling and drafting may be carried out two or three timesusing identical machines. One operation does not usually give sufficientregularity, fibre parallelism and blending

Fibre parallelism means that the fibres are running parallel to each otherlengthwise along the strand

Parallel fibres are the key to fine yarns and higher yarn strength

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PPS 1.24Combing

Removes short fibres, leaving longest fibres

Fibres are prepared in the form of a lap which

is even in thickness with fibres parallel to the

length of the lap

Only best quality yarns are combed due to

cost

Combing produces a cleaner, finer, more even

yarn

Roving

PPS 1.25

Outline the roving process using the PPSs:

Roving

Roving reduces the thickness of the sliver to

10 to 15% of its original thickness

This process involves drawing the slivers

through pressure rollers running at varying

speeds

This size reduction (from approx. 5,000 grams

per km to approx. 600 grams per km) gets the

feeder material right for the next process, ie.

ring spinning

PPS 1.26Roving

After the thickness is reduced the material is called

Roving and the machine used here is either called aRoving frame or Simplex frame

The roving is wound on to spools weighing up to 2 to

3kg in the roving frames

These rovings are held together without breaking by

having it twisted slightly

The twist given to the roving is a false twist, since this

is removed whilst unwound in the ring frame

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Spinning

PPS 1.27

Outline the speed frame using the PPS:

Spinning: Speed Frame

Roving

on

Bobbin

Draws sliver to reduce it to a

fineness suitable for spinning

Inserts a small amount of twist

to strengthen the roving

Winds the roving onto a

bobbin ready for spinning

Speed Frame

Carding

Combing

Spinning


Both the carded and combed slivers go through the speed frame Adding twist to the yarn adds strength Drafting is another term for drawing

PPS 1.28

Outline the spinning process using the PPS:

Spinning

Roving

on

Bobbin

Yarn

on

Bobbin

Draws roving to reduce the

thickness

Adds twist to strengthen yarn

Winds yarn evenly onto

bobbin in preparation for

weaving

Spinning

WeavingSpeed

Frame

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PPS 1.29

Explain the key differences between ring spinning and open end spinning using

the PPSs:

Ring Spinning

Used for finer yarns

and all combed yarns

Involves 6 processes

for carded ring spun

yarn and 8 processes

for combed ring spun

yarn

PPS 1.30

Outline winding using the PPS:

Winding

The ring spun yarn is wound on small ring tubes calledRing Cops mounted on spindles on the ring frames

Since the format of this package is so small, this yarn hasto be rewound on to larger cones

This process is called winding

During the winding process, any weak spots in the yarnsare removed and clear of any contamination, thick places orother faults

Yarn from ring tubes which is approx around 50 grams pertube is wound on to larger cones up to 4 kg

This yarn is packed and transported to the end user suchas a knitter or weaver

PPS 1.31

Outline twisting using the PPS:

Twisting

Twisting is used to make ply yarns for specificend uses

The end product out of spinning is always a

single ply yarn

This can be doubled along with an identical

yarn to form a doubled ply yarn

This is achieved through twisting frames

The process is achieved in two stages

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PPS 1.32

Outline assembly winding using the PPS:

Assembly Winding

In this process the two single yarns are assembled

next to each other and wound on to a parallel package

This package is then fed on to the twisting frame

The twisting frame draws the assembled single

threads and twists it together to the pre set twist

The direction of twisting whilst doubling is always

opposite to that of the single yarn

This is done to retain a balanced yarn for subsequent

processing

PPS 1.33

Outline open end spinning using the PPS:

Open End Spinning

Also known as rotor

spinning

Generally used on

coarser counts of

yarn

Not used for combed

yarn Involves 4 stages or

processes

Notes on PPSs:

The two most popular methods of spinning are ring spinning and open endspinning

The open end spinning is a relatively new technology compared to ringspinning

In Ring Spinning, the cotton fibres are twisted to form the yarn by threadingthe fibres through a small ear shape metal piece called a traveller onto thehigh-speed ring tube

The fibre is held in cohesion through out the transition stage from fibre to yarn The yarn produced by ring spinning is known as ring spun yarn In Open end spinning, the fibres are inserted loose into a spin box

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The spin box consists of a funnel spinning at speeds of over 50,000 rpm The cotton fibres direct from the sliver form are fed into the funnel from the

outer rim of the spinning funnel

The fibres coming into contact with the inner walls of the spinning funnel getthrown along the surface by centrifugal force

The fibres are then guided through a fine groove in the inner surface of thefunnel and drawn out from the centre of the funnel

The drawn yarn is wound directly onto packages ready for delivery to the enduser

The yarn produced by rotor spinning is known as open ended yarn In open end spinning, both the roving process for pre Ring spinning and the

winding process for post Ring spinning is eliminated

The cost of Open end spinning is therefore reduced dramatically compared toring spinning

PPS 1.34

Outline vortex spinning using the PPSs:

Vortex Spinning

This is a recent invention (1997) on spinning

methods as a further advancement to the open

end (OE) spinning

The production output rates are double of that

of OE spinning and the quality of the yarn is

closer to that of the ring spun yarn

The cotton fibre used must have a long staple

length (28mm and above) and be stronger

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PPS 1.35Vortex Spinning

In vortex spinning, the drafted f ibres are sucked into a

nozzle where a high speed 'vortex' air current wraps

the fibres around the outside of a hollow stationary

spindle

A vacuum around the base of the spindle acts to

'comb' out shorter fibres and neps

Fibres are pulled down a shaft that runs through the

middle of the spindle

Yarn twist is inserted as the fibres swirl around the

apex of the spindle before being pulled down the

spindle shaft

Notes on PPS:

This system has the same advantages of the OE spinning as the yarn isproduced directly from the sliver without any roving process and thelimitation of the ring spinning processes

PPS 1.36

Blending of Cotton with other

Fibres

Though not used in terry towel production, cotton

fibre is blended with many other man made fibres

to achieve excellent end products

One of the most popular cotton blended yarn is

Poly cotton

The Poly cotton yarn is popularly used in apparels,

as the cotton component takes care of the

moisture absorbency, the polyester gives the

required durability and design/colour feature to the

product

Notes on PPS:

Cotton is also blended with regenerated cellulosic fibres like staple viscose In this blend both fibres have very similar characteristics due to the cellulosic

fibres

The blending is usually done in the draw frame or the blow room of thespinning mill

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Resource Material


PPS 1.38: Cotton Properties PPS 1.39: Cotton Varieties PPS 1.40: Egyptian Cotton PPS 1.41: Pima Cotton PPS 1.42: Upland Cotton Handout 1.5Aim

The aims of this section of the module are to familiarise participants with the:

properties of each variety in relation to towelling products different varieties of cottonTiming

10 minutes

The estimated time for Cotton Types and Properties is 10 minutes.

The information is presented using the PPSs and samples

Trainers Notes


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Cotton Properties

PPS 1.38

Outline the characteristics and properties of cotton that make it such a valuable

and sought after fibre. Highlight those that are particularly valuable and desirablein the production of towelling

Cotton Properties

Handle

Absorbency

Felting

Laundering

Durability

Hypoallergenic

Colour Clarity

Colour Retention

Shrinkage

Versatility

The characteristics and properties that are valuable/desirable in the production of

towelling products are shown below:

Handle Soft and comfortable feel

Drapes well

No static electricity

Absorbency Naturally absorbent

Can absorb up to 1/5 of its weight before it feels damp

Can absorb 24 - 27 times its own weight

Is stronger wet than dry

Felting Does not felt or mat like wool

Does not form pill(s) like wool,

acrylic or polyester fibre

Laundering Machine washable

Can be sterilised/sanitisedCan be tumble dried

Dry cleanable

Durability Long-lasting if well looked after

Hypoallergenic Does not irritate sensitive skin or cause allergies

Colour

Retention &

Clarity

Easily dyed

Prints well

Reflects colour well

Retains colour

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Shrinkage Occurs only to remove stretching in manufacture

Occurs usually only at first wash

Occurs the least in leading brand quality products

Versatility Easy to handle and sew

Can be easily blended with other fibres

Can be treated, eg. for heat resistance, wrinkle resistance,stain resistance or permanent press

Cotton Varieties

PPS 1.39

Name the three main varieties of cotton using the PPS:

Cotton Varieties

Egyptian

Pima

Upland

There are many varieties of cotton used in

towel production, some are:

PPS 1.40

Outline the properties of Egyptian Cotton using the PPS:

Egyptian Cotton

Extra Long Staple (ELS) cotton grown in Egypt

is classified as Egyptian cotton

Generally regarded as best cotton fibre

Natural colour enhances colour of final product

Roller ginned because of its long fibre length

Generally combed and ring spun

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PPS 1.41

Outline the properties of Pima Cotton using the PPS:

Pima Cotton

Pima cotton is ELS length cotton

Originated in Peru

Hybrid of Upland and Sea Island cotton

Grown primarily in the USA, Australia and Peru

Longer and stronger fibre


Spun into higher count yarns for better qualityproduct

Can be made into fine quality fabric

Relatively costly to produce and to process


What is Supima?Licensed brand name for Pima cotton

PPS 1.42

Outline the properties of Upland Cotton using the PPS:

Upland Cotton

Originally named American Upland but

commonly called Upland Grown in many countries, including Australia

Average staple length is 2 to 3 centimetres

Most commonly available cotton

Light cream to off-white in colour

Either combed or carded

Can be ring or open end

Used for large range of very good to averagequality cotton goods

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Resource Material


PPS 1.43: Cotton Count Systems PPS 1.44: English Cotton Count PPS 1.45: Tex Direct System PPS 1.46: Yarn Count Conversion PPS 1.47: Ring Spun Cotton PPS 1.48: Open End Yarn Handout 1.6 DVDAim

The aims of this section of the module are to provide participants with a working knowledge of:

cotton counts and their application in the manufacture and retailing of towelling products the types of yarn used in the manufacture of towelling productsTiming

15 minutes

The estimated time for Cotton Counts and Yarns is 15 minutes.

The information is presented using PPSs and samples.

Trainers Notes


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Cotton Counts

PPS 1.43

Give an overview of cotton count systems using the PPS:

Cotton Count Systems

All yarn count systems measure lineardensity to denote the thickness andheaviness of the yarn

Indirect Systems are based on:

Length per Unit Weight

Direct Systems are based on:

Weight per Unit Length

PPS 1.44

Explain the English Cotton Count System using the PPS:

English Cotton Count

English Cotton Count or ECC is an indirect

system

The basic unit is an Nec

A Nec is the number of hanks, each 840 yardsin length required to weigh 1 pound, ie.

Nec = 840 yards / 1lb

The higher the Ne number the finer the yarn,

the lower the Ne number the thicker the yarn

PPS 1.45

Explain the Tex System using the PPS:

Tex Direct System

Basic unit is the Tex

A Tex is the weight, in grams, per 1,000

Metres or 1 kilometre of the yarn

Tex = grams / 1,000 metres

The higher the Tex number the thicker

the yarn, the lower the Tex number the

finer the yarn

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PPS 1.48

Outline the characteristics and properties of open end cotton using the PPS:

Open End Yarn

Can have a harsher feel if not treated

correctly

Hard wearing and durable

Great absorbency due to the hollow

structure of the yarn

Used for the ground or base of the towel

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This section contains the following resource material for Module 1. Cotton:

Glossary Assessment Tasks Learning Checklist Handouts

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Glossary

Bale A basic tradeable unit of lint or ginned cotton. In Australia a standard

bale weighs 227kgs.

Blending Fibres from different bales of cotton are mixed together to make sure

that the spun yarn is uniform in physical characteristics such as stapleand colour.

Blowing Room The room in a cotton spinning mill where the preparatory processes of

opening, cleaning and blending occur.

Bobbin A cone shaped object that holds yarn.

Boll The fruit or seed pod of the cotton plant. The boll contains the cottonfibre, which are long, white hair like fibres attached to the cotton

seeds.

Each boll contains about 30 seeds and up to 500,000 fibres of cotton.

Carded yarn Carding of the cotton fibre is the basic method of preparing cotton for

spinning. It basically draws and lays the fibres parallel to each other in

preparation for the spinning process.

Carding The cotton fibres are combed using a carding machine to make them

run in straight lines.

Each line of fibre is called a sliver.

Combed yarn Combed yarn has been processed to remove the shorter fibres before

the spinning process leaving the longer fibres. The longer the fibres the

better the quality, yarn fineness, strength, fibre shedding and colour

intensity.

Creel A structure for holding bobbins or cheeses of yarn.

Delinting Removal of the fibres that remain on the cotton seed after ginning.

Once the fibres have been removed the cotton seed can be furtherprocessed into oil or used to planting.

Gin A machine designed to remove the cotton fibres (lint) from the cotton

seed.

Lap A long roll of cotton.

Lint Cotton fibre produced by the ginning process once the cotton seed,

leaves and casing have been removed. Lint is used to produce cotton

yarn.

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Linters Very fine, short fibres which are still attached to the cotton seed after

ginning.

Linters are chemically removed and used in the manufacture of rayonand other products.

Motes A mixture of trash and fibre as a by-product of ginning.

The fibre can be used for lower grade cotton yarns and paper but

requires special opening and cleaning.

Nep A small knot of entangled fibres, usually dead or immature cotton

hairs.

Opening The separating of closely packed fibres of cotton. Opening occurs in

the early stages of processing raw cotton into yarn.

Picker A machine used to harvest cotton that removes the seeded cotton fromthe boll.

Roving Relatively fine fibrous strands used in the later or final processes of

preparation for spinning.

Ring Spinning A yarn spinning method in which roving (a thin strand of fibre with

very little twist) is fed to a "traveler" which rotates around the edge of a

ring. Inside the ring is a faster rotating bobbin. The process

simultaneously draws and twists the roving into yarn and winds itaround the bobbin.

Rotor Spinning A method of open-end spinning which uses a rotor (a high speed

centrifuge) to collect individual fibres into a yarn. The fibres on

entering a rapidly rotating rotor are distributed around its

circumference and temporarily held there by centrifugal force. The

yarn is withdrawn from the rotor wall and because of the rotation, twist

is generated.

Sliver An assembly of fibres in continuous form without twist.

Spinning The final stage of cotton processing using machines that stretch out thecotton sliver and make it into long, thin threads of yarn.

Staple Length of the cotton fibres, eg. short staple length or long staple length.

Stripper A machine used to harvest cotton that strips the entire boll off the

plant.

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Assessment Tasks

1. When did cotton first come into Australia?

2. When did cotton become a major crop and the surplus exported?

3. Mark on the map of Australia the main cotton growing areas.

4. Complete on the diagram the stages of the cotton growing cycle.The Cotton Cycle

100 days


days

GROWING

SEASON

DAY 0

DAY

180

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5. What advantages does machine harvesting have over hand picking?

6. What advantages does hand picking have?

7. What is the purpose of ginning cotton?

8. Which by-products of ginning are used to produce cotton?

9. Why is cotton cleaned?

10. How is the cotton carded?

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11. What is the main reason that cotton is combed?

12. What are the key differences between ring spun yarn and open end yarn?

13. Why are these cotton properties important features of towelling products?a. Handleb. Absorbencyc. Launderingd. Durabilitye.

Colour Retention & Clarity

14. Name two major cotton varieties used in the production of towelling products. Describethe properties of each

a.

b.

15. What are the two types of cotton count systems? Give an example of each systema.

b.

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Learning Checklist

LearningOutcomes

Assessment Tasks ResultsDemonstratesCompetence

Yes No

Learning Outcome 1

Identify a key milestone for theAustralian cotton industry

When did cotton first come into Australia?

When did cotton become a major crop and the surplusexported?

Learning Outcome 2

Identify the main cotton growing areasin Australia

Mark on the map of Australia the main cotton growingareas

Learning Outcome 3

List the key steps in the cotton growingcycle

Complete on the diagram the stages of the cotton growingcycle

Learning Outcome 4

Identify the differences between

machine picking and hand picking

What advantages does machine harvesting have over handpicking?

What advantages does hand picking have?

Learning Outcome 5

State the purpose of ginning cotton

What is the purpose of ginning cotton?

Which by-products of ginning are used to produce cotton?

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LearningOutcomes


Yes No

Learning Outcome 6

Identify the key reasons for cleaningcotton

Why is cotton cleaned?

Learning Outcome 7

Outline the steps in carding

How is the cotton carded?

Learning Outcome 8

Explain the primary purpose of combing

What is the main reason that cotton is combed?

Learning Outcome 9

Describe the differences between ringspun and open end yarn

What are the key differences between ring spun yarn andopen end yarn?

Learning Outcome 10

Describe the characteristics andproperties of cotton that are mostrelevant to towelling products

Why are these cotton properties important features oftowelling products?

a. Handleb. Absorbencyc. Launderingd. Durability

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LearningOutcomes


Yes No

e. Colour Retention & Clarity

Learning Outcome 11

Identify the main types of cotton usedin towelling manufacture and describethe properties of each

Name two major cotton varieties used in the production oftowelling products. Describe the properties of each

Learning Outcome 12

Outline the two types of cotton countsystems

What are the two types of cotton count systems? Give anexample of each system

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Cotton: from Grower to User 1 of 1Prepared byEffective ChangePty Ltd

Unit 1: Introduction

Cotton from Grower to User

Module 1:COTTON

Introduction

Cotton: Fundamentals & History

Growing & Harvesting Cotton

Cotton Properties & Varieties

Cotton Counts & Yarns

Cotton Processing


Introduction

Yarn Preparation

Weaving

Drying

Finishing

Dyeing

Finished Product

Module 3:COLOUR &

DECORATING

Introduction

Colour Forecasting

Psychology of Colour

Colour Harmonies

Colour: FAQs

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Unit 2: Cotton: Fundamentals and History

What is Cotton?

Cotton fibres are the seed hairs of the plantGossypium

Each fibre is formed by the elongation of a single cellfrom the surface of the seed

The word cotton is derived from its Arabic namepronounced kutan, qutn or qutan

Under a microscope, acotton fibre appears asa very fine, regular fibre,looking like a twistedribbon. These twists arecalled convolutions

Fundamentals of Cotton

Cotton is composed of long cellulosic molecules

It is typically around 88 96% cellulose. The rest is

protein, pectic substances, ash and wax

After scouring and bleaching, cotton is then about 99%

cellulose

The cellulosic wall of the cotton fibre give cotton itsunique characteristics: its crimp, wall thickness,

maturity, pliability, moisture absorbance and

retainability

These characteristics contribute to making cotton the

most sought after natural fibre in the world

Cotton Fibre

The cotton fibre length varies with the

type and quality

It is stronger when wet

Cotton absorbs moisture readily, which

makes cotton clothes comfortable to

wear in warm weather (water retention of

50%, moisture regain of 7%)

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History of Cotton

USA producing > 50% of worlds cotton1920s

Cotton gin invented1793

Cotton seeds arrive in Australia on First Fleet1788

Spinning Jenny invented in England1769

India produced fine quality cotton fabric.

Grown in the USA, China, Japan, Middle East

& Pakistan

3,000years ago

Remnants found woven with feathers & fur5000

years ago

Cotton is one of the oldest known fibres It has been grown and used for more than 5,000 years Cotton was first cultivated in Pakistan Invention of the Spinning Jenny in England enabled cheap mass-production Invention of the Cotton Gin in the USA to remove the seeds from cotton fibre lead to further

improvements in production

History of Cotton in Australia

Environmental audit and introduction of Best

Management Practices

1992

Cotton production increases as availability of

irrigation increases

1970s

First exportable surplus produced

Emerged as major crop

Cotton consistently profitable

1960s

Cotton industry all but non-existent1954

Australia fills gap caused by the US Civil War1861 >

Cotton seeds arrive on First Fleet1788

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Growth in Cotton Production

0

0.5

1

1.5

2

2.5

3

3.5

1980 1985 1992 1995 1997 1999

Millions of Bales

1830 3 bags of cotton were exported to England




1992 Production was about 2% of the worlds ginned cotton

1995 Production dropped due to drought

The Australian cotton industry:

is internationally competitive is increasingly efficient at processing cotton has a substantial share of its total production exported as cotton yarn, fabric or finishedproduct

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Unit 3: Growing and Harvesting Cotton

Growing Cotton

Ideal Growing Conditions

Cotton needs:

Warm, humid climate or a warm climate

with adequate irrigation

Long, frost-free period of 6-7 months

Mild temperatures

About 12 hours of sunlight per day

During the growing cycle 7.5cm12.5cmof rain monthly or adequate irrigation

China is the leading producer of cotton world-wide Other major producers are the USA, the states of the former Soviet Union, India, Pakistan,

China, Brazil and Australia

Cotton Growing in Australia

Qld

NSW

Cotton is primarily grown in central and north-western NSW and central and southernQueensland

Approximately 70% of Australias cotton is produced in NSW, with most of it being grownin the Murray-Darling Basin

The majority of cotton grown in Australia is irrigated cotton There are few areas in Australia suitable for non-irrigated or dryland cotton growing Hence most cotton is grown on land near major irrigation schemes and river valleys

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The Cotton Cycle

Cotton Seed

Planted

Open BollCotton Blossoms

Boll

Harvest 100 days


days

GROWING

SEASON

DAY 0

DAY180

From planting time to harvesting time is approximately 180 days or about 6 months

Day 1: Cotton seed is planted

Day 3-5: Seedlings appear

Day 100: Cotton blossoms

The cotton plants blossom over a period of time and their

yellowish/pink flowers bloom for 1 day

By the end of the 2nd day the flowers wither and drop to reveal

the formation of the boll or young seed podBetween Blossoming and

Maturity

Bolls grow and mature

It is during this time in the growing cycle that the bolls need

adequate rainfall or irrigation

Day 150 -180: Bolls open to reveal the white fluffy cotton

Each boll contains about 30 seeds and up to 500,000 fibres of

cotton

Again the bolls do not all open together so the picking season

occurs over a period of time.

In Australia most on-farm activities related to cotton growing occur in Australia between August

and May

August September: Soil Preparation

September October: Planting

November February: Growing Season

March May: Picking and Ginning

Cotton comes come from the Arabic word kutun which describes a fine textile Cotton is a bushy plant that is a member of the Hibiscus family

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Harvesting Cotton

Harvesting: Machine Picking

Cotton is harvested by either a:

Cotton Picker: removes the cotton from

the bolls without damaging the plant

Cotton Stripper: strips entire boll off the

plant

Australian cotton is harvested by pickers because the cotton

is cleaner

Cotton pickers give much greater cleaning efficiency as the picker does not collect as muchtrash, or unwanted twigs and leaves, as a cotton stripper. Cotton that is cleaner when it is

picked lessens the requirement for cleaning during the ginning process Machine picking of cotton allows mass harvesting Australia, the USA and Israel are the only countries in the world to harvest their cotton

exclusively with machines

Harvesting: Hand Picking

Hand picking cotton:

is slower than machine picking

better preserves fibre characteristics

leaves behind unwanted trash like

leaves and boll

selects fully grown cotton and leaves

young cotton for later picking

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Unit 4: Cotton Processing

Overview of Cotton Processing

Cotton Processing

Cotton

FieldsGinning Classing

Spinning

Mills

Bailing

Ginning

Ginning

Ginning separates the cotton fibres from thecotton seed

Lint - fibre

Picked Cotton

Drying and

Removing Trash

Classing

Mote trash & fibres

Seed linters & seed

Bailing

The primary purpose of ginning is to separate the cotton fibre from the cotton seeds. Thisprocess is carried out by a machine called a gin

There are two types of gin: saw gins and roller gins In a saw gin, circular saws grip fibres and pull them through narrow slots leaving the seed

behind. Saw gins are used with shorter fibres

Saw gins are primarily used in Australia because we grow more short staple length cotton In a roller gin a rough roller grabs fibres and pulls them under a rotating bar with gaps too

small for seed. Roller gins are used with longer fibres

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The by-products of ginning are:Lint:

Lint is the technical name for cotton fibre produced in the ginning process Lint is used to produce cotton yarnMotes:

Mixture of trash like dirt, stalks, leaves and fibre The fibre can be used for lower grade cotton and paper but requires furtherprocessing

Seed:

Seed contains linters or short, very fine fibres The cleaned seed is crushed to produce cotton seed oil and the residue can be used

for cattle feed. It may also be used as seeds to plant again for the next cotton crop

The word gin in cotton gin is related to the word engine and means device. It is unrelated tothe alcoholic drink called gin!

55% of ginned cotton is made up of cottonseed, 35% is lint and 10% is trash. Cotton fibre waste has been used to clean up oil spills in the sea, as it soaks up the oil well

but the natural waxes that it contains help to keep the fibre afloat. Cotton trash such as left

over sticks and leaves can be used as compost, and put back into the soil.

Fibre is measured

against a set of

standards orgrades toassesses quality

of ginning,

fineness and fibre

length.

Classing & Baling

Ginning Classing

Lint is pressed

into bales of a

standard size

Bailing

Classing is the process of measuring the fibres against a set of standards or grades. The lint isgraded on a scale of 1 to 6, which assesses the quality of ginning, fineness and fibre length.

Raw fibre or lint is passed from the gin through pipes to a press The press compresses the lint into bales Each bale weighs 227 kg or 500 lbs, which is the standard Australian size. The standard bale

size for the rest of the world is 400 lbs. A sample for classing is taken from every bale The bales are then sold to local spinning mills or overseas buyers or they are storedA standard Australian bale of cotton makes approximately 500 light bath towels

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Cleaning

Cleaning

Ginning

Removes

Seeds

Lint & Trash

Ginning

Cleaned

Blended

Leaf

Stalk

Sand

Soil

Dust

Removes40-70%

Trash

Ginning removes seeds but not trash Trash is leaf, stalk, sand, soil and dust that is mixed in with the lint Lint needs to be opened, cleaned and blended to remove the trash

CleaningBales

of Lint

Opening Blending Cleaning

CardingSeparator opencotton

Break it into small

tufts or flocks

Blow Room

Blend or mix fibres

from different balestogether

Create uniformity of

staple and colour

Beaters

progressively opencotton

Release trash

Lap

3-7 major cleaningpoints

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Carding

CardingCleaningBlow Room

Opening &

Cleaning

Removes short fibres

Disentangles neps (knots)

Partially aligns fibres length wise

Blends fibres into web

Removes 80-90%Dust & Impurities

Carding Machine

Lap

(long roll

of cotton

Single

Fibres

Drawing

Sliver (long,

loose strand

of cotton)

Fibres

Brushes, cleans, disentangles and straightens the cotton fibre All yarn is carded The sliver is output into cans for storageDrawing

Drawing

Sliver

Straightens and parallelises the fibres

Blend slivers to improve regularity of

weight, length

and fibre mix

Draw out slivers

to produce

slivers of

required weightand length

Drawing

Carding Combing

Spinning

The carded slivers are coiled in cylindrical cans with spring-loaded bases so that there is notension applied to the slivers when drawn out. In the sliver the cotton fibres are not parallel

The carded slivers then are passed through a drawing process:slivers are laid parallel in groups of 6 or 8 and passed through high-speed pressure rollersthe speeds of these rollers are varied so that the group of is "drawn" to form a singlesliver

The slivers vary in thickness. Feeding slivers together is known as doubling and leads to animprovement in regularity in the sliver. When fed together the thick part of one sliver isoffset by the thin part of another

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This process improves the uniformity of the sliver because of the multiple doubling Doubling feeds multiple slivers together and so it blends the fibres too Each succeeding pair of rollers runs faster than the preceding pair. The fibres are gripped by

a faster pair and drawn out from the preceding slower pair The action of reducing the thickness of the feed sliver (input) by drawing is known as

drafting The operation of doubling and drafting may be carried out two or three times using identicalmachines. One operation does not usually give sufficient regularity, fibre parallelism andblending. Fibre parallelism means that the fibres are running parallel to each otherlengthwise along the strand

Parallel fibres are the key to fine yarns and higher yarn strengthCombing

Combing: Lap Former This process is used to prepare the feeder material for

the combing operation

Similar to the drawing process, slivers are laid parallel

and passed through high speed rollers to form a sheet

of compressed cotton lap, which is wound on to spools

The spools of cotton laps are then transported to the

comber for the crucial combing process

Instead of single slivers, these laps are the feeder

material for the combing process

Combing: Comber

Metal combs tease the cotton lap fed between pressure

rollers, so that the combing process individually separates

every cotton fibre

The amount of short fibre reduction can be controlled by

adjusting the combs in the combing machine

Whilst the fibres are combed, all short fibres and trash are

removed form the cotton

The trash, called Noil can be re used in spinning of coarsercounts of yarn or for waste spinning processes for making

mop yarns etc

Around 18-20 % of re-usable cotton waste (Noil) is

extracted during this process

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Combing: Grouping of the Combed

Sliver One comber machine will have commonly up to eight

comber heads

The combed slivers from all the different combing headsare grouped together along a stainless steel table andpassed through a Drawing process

This drawing process serves the purpose of doubling toimprove the uniformity in the combed sliver

This drawn / combed sliver is coiled individually incylindrical cans with coil springs similar to the gathering ofthe sliver after carding

The combed slivers are further re-processed throughdrawing frames to improve the uniformity and blendingbefore proceeding to the next process

Combing

Removes short fibres, leaving longest fibres

Fibres are prepared in the form of a lap which

is even in thickness with fibres parallel to the

length of the lap

Only best quality yarns are combed due to

cost Combing produces a cleaner, finer, more even

yarn

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Roving

Roving

Roving reduces the thickness of the sliver to

10 to 15% of its original thickness

This process involves drawing the slivers

through pressure rollers running at varying

speeds

This size reduction (from approx. 5,000 grams

per km to approx. 600 grams per km) gets the

feeder material right for the next process, ie.

ring spinning

Roving

After the thickness is reduced the material is called

Roving and the machine used here is either called a

Roving frame or Simplex frame

The roving is wound on to spools weighing up to 2 to

3kg in the roving frames

These rovings are held together without breaking by

having it twisted slightly

The twist given to the roving is a false twist, since this

is removed whilst unwound in the ring frame

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Spinning

Spinning: Speed Frame

Roving

on

Bobbin

Draws sliver to reduce it to a

fineness suitable for spinning

Inserts a small amount of twist

to strengthen the roving

Winds the roving onto a

bobbin ready for spinning

Speed Frame

Carding

Combing

Spinning

Both the carded and combed slivers go through the speed frame Adding twist to the yarn adds strength Drafting is another term for drawing

Spinning

Rovingon

Bobbin

Yarnon

Bobbin

Draws roving to reduce thethickness

Adds twist to strengthen yarn

Winds yarn evenly onto

bobbin in preparation for

weaving

Spinning

WeavingSpeed

Frame

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Ring Spinning

Used for finer yarns

and all combed yarns Involves 6 processes

for carded ring spun

yarn and 8 processes

for combed ring spun

yarn

Winding

The ring spun yarn is wound on small ring tubes calledRing Cops mounted on spindles on the ring frames

Since the format of this package is so small, this yarn hasto be rewound on to larger cones

This process is called winding

During the winding process, any weak spots in the yarnsare removed and clear of any contamination, thick places orother faults

Yarn from ring tubes which is approx around 50 grams pertube is wound on to larger cones up to 4 kg

This yarn is packed and transported to the end user suchas a knitter or weaver

Twisting

Twisting is used to make ply yarns for specificend uses

The end product out of spinning is always a

single ply yarn

This can be doubled along with an identical

yarn to form a doubled ply yarn

This is achieved through twisting frames

The process is achieved in two stages

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Assembly Winding

In this process the two single yarns are assembled

next to each other and wound on to a parallel package

This package is then fed on to the twisting frame

The twisting frame draws the assembled single

threads and twists it together to the pre set twist

The direction of twisting whilst doubling is always

opposite to that of the single yarn

This is done to retain a balanced yarn for subsequent

processing

Open End Spinning

Also known as rotor

spinning

Generally used on

coarser counts of

yarn

Not used for combed

yarn

Involves 4 stages or

processes

The two most popular methods of spinning are ring spinning and open end spinning The open end spinning is a relatively new technology compared to ring spinning In Ring Spinning, the cotton fibres are twisted to form the yarn by threading the fibres

through a small ear shape metal piece called a traveller onto the high-speed ring tube

The fibre is held in cohesion through out the transition stage from fibre to yarn The yarn produced by ring spinning is known as ring spun yarn In Open end spinning, the fibres are inserted loose into a spin box The spin box consists of a funnel spinning at speeds of over 50,000 rpm The cotton fibres direct from the sliver form are fed into the funnel from the outer rim of the

spinning funnel The fibres coming into contact with the inner walls of the spinning funnel get thrown along

the surface by centrifugal force The fibres are then guided through a fine groove in the inner surface of the funnel and drawn

out from the centre of the funnel The drawn yarn is wound directly onto packages ready for delivery to the end user

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The yarn produced by rotor spinning is known as open ended yarn In open end spinning, both the roving process for pre Ring spinning and the winding process

for post Ring spinning is eliminated The cost of Open end spinning is therefore reduced dramatically compared to ring spinning

Vortex Spinning

This is a recent invention (1997) on spinning

methods as a further advancement to the open

end (OE) spinning

The production output rates are double of that

of OE spinning and the quality of the yarn is

closer to that of the ring spun yarn

The cotton fibre used must have a long staplelength (28mm and above) and be stronger

Vortex Spinning

In vortex spinning, the drafted fibres are sucked into a

nozzle where a high speed 'vortex' air current wrapsthe fibres around the outside of a hollow stationary

spindle

A vacuum around the base of the spindle acts to

'comb' out shorter fibres and neps

Fibres are pulled down a shaft that runs through the

middle of the spindle

Yarn twist is inserted as the fibres swirl around the

apex of the spindle before being pulled down the

spindle shaft

This system has the same advantages of the OE spinning as the yarn is produced directlyfrom the sliver without any roving process and the limitation of the ring spinning processes

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Blending of Cotton with other

Fibres

Though not used in terry towel production, cotton

fibre is blended with many other man made fibres

to achieve excellent end products

One of the most popular cotton blended yarn is

Poly cotton

The Poly cotton yarn is popularly used in apparels,

as the cotton component takes care of the

moisture absorbency, the polyester gives the

required durability and design/colour feature to the

product

Cotton is also blended with regenerated cellulosic fibres like staple viscose In this blend both fibres have very similar characteristics due to the cellulosic fibres The blending is usually done in the draw frame or the blow room of the spinning mill

Cotton Fibre Testing

The key quality parameters defining the characteristics of the

cotton fibre are:

The staple length of the cotton stated in millimetre ranges

The fibre fineness or maturity stated as Micronaire value

The fibre strength

The cotton colour

The trash content

Presence of honey dew produced by aphids which causesa sticky sugary substance to foul the cotton, or any other

pest damage

Technology has been developed to assess these parameters accurately As cotton is a naturally grown product, these characteristics will vary from crop to cropdepending on the soil and weather conditions

It is therefore crucial that these parameters are well tested before blending of different lots ofcotton in the spinning mill

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Unit 5: Cotton Properties and Varieties

Cotton Properties

Cotton Properties

Handle

Absorbency

Felting

Laundering

Durability

Hypoallergenic

Colour Clarity

Colour Retention

Shrinkage

Versatility

The characteristics and properties that are valuable/desirable in the production of towelling

products are shown below:

Handle Soft and comfortable feel

Drapes well

No static electricity

Absorbency Naturally absorbent

Can absorb up to 1/5 of its weight before it feels dampCan absorb 24 - 27 times its own weight

Is stronger wet than dry

Felting Does not felt or mat like wool

Does not form pill(s) like wool, acrylic or polyester fibre

Laundering Machine washable

Can be sterilised/sanitised

Can be tumble driedDry cleanable

Durability Long-lasting if well looked after

Hypoallergenic Does not irritate sensitive skin or cause allergies

Colour

Retention &

Clarity

Easily dyed

Prints well

Reflects colour well

Retains colour

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Shrinkage Occurs only to remove stretching in manufacture

Occurs usually only at first wash

Occurs the least in leading brand quality products

Versatility Easy to handle and sew

Can be easily blended with other fibresCan be treated, eg. for heat resistance, wrinkle resistance, stain resistance

or permanent press

Cotton Varieties

Cotton Varieties

Egyptian

Pima

Upland

There are many varieties of cotton used intowel production, some are:

Egyptian Cotton

Extra Long Staple (ELS) cotton grown in Egypt

is classified as Egyptian cotton

Generally regarded as best cotton fibre

Natural colour enhances colour of final product


Generally combed and ring spun

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Pima Cotton

Pima cotton is ELS length cotton

Originated in Peru

Hybrid of Upland and Sea Island cotton

Grown primarily in the USA, Australia and Peru

Longer and stronger fibre


Spun into higher count yarns for better qualityproduct

Can be made into fine quality fabric

Relatively costly to produce and to process

Upland Cotton

Originally named American Upland butcommonly called Upland

Grown in many countries, including Australia

Average staple length is 2 to 3 centimetres

Most commonly available cotton

Light cream to off-white in colour

Either combed or carded Can be ring or open end

Used for large range of very good to averagequality cotton goods

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Unit 6: Cotton Counts and Yarns

Cotton Counts

Cotton Count Systems

All yarn count systems measure lineardensity to denote the thickness andheaviness of the yarn

Indirect Systems are based on:

Length per Unit Weight

Direct Systems are based on: Weight per Unit Length

English Cotton Count

English Cotton Count or ECC is an indirect

system The basic unit is an Nec

A Nec is the number of hanks, each 840 yards

in length required to weigh 1 pound, ie.

Nec = 840 yards / 1lb

The higher the Ne number the finer the yarn,

the lower the Ne number the thicker the yarn

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Tex Direct System

Basic unit is the Tex

A Tex is the weight, in grams, per 1,000

Metres or 1 kilometre of the yarn

Tex = grams / 1,000 metres

The higher the Tex number the thicker

the yarn, the lower the Tex number the

finer the yarn

The Tex System is regarded as an international system It is now used in most countries, with the exception of the US

Yarn Count Conversion

From Tex

To:

From ECC (Ne)

To:

Ne = 590

tex

Tex = 590

Ne

Den = 9 x texDen = 5,314

Ne

You cannot directly compare a count from one system to another. You must do theconversion

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Cotton Yarns

Ring Spun Cotton

Ring spun cotton in a finished towel product issofter to the touch

Generally needs less finishing treatments togive a soft handle

Stronger yarn and handles abrasion and wearbetter

More robust/flexible for handling andproduction

Has good colour reflection and betterbrightness

Open End Yarn

Can have a harsher feel if not treated

correctly

Hard wearing and durable

Great absorbency due to the hollowstructure of the yarn

Used for the ground or base of the towel

Documents

1.10 Module_1_V2.pdf