Fibre to fabric P Choudhury Fibre to Fabric
Fibre to fabric P Choudhury
Fibre to Fabric • Fibre-----yarn (thread)------Fabric • Based on their sources, fibres can be classified into two types • Natural Fibre- We get natural fibres from plants and animals. Cotton, jute, silk and wool are natural fibre. Natural fibre can be classified into plant fibre and animal fibre • Artificial fibres- Human made artificial fibre using chemicals in factories. Nylon and polyester are examples of artificial fibres.
Wool • Wool is an animal fibre that is generally obtained from the hair of fleece of sheep. Wool fibre is natural fibre • Wool from sheep= A sheep has two types of hair on its body- Coarse beard hair and soft under hair that is close to its skin. The under hair is used to make wool.
Selective breeding • The process in which parents are specially selected to produce offspring ( Young ones) that have certain qualities is called selective breeding • Sheep rearing- In india, sheep are reared for wool in dry, hilly areas
• Names of breed • Marwari • Karnah • Lohi • Bakharwal • Patanwadi types of wool Coarse wool used to make carpets Used to make cloths Good quality wool used to make carpet Used to make shawls Used to make socks.
Other wool producing animals • Angora rabbit- The angora rabbit is a domestic rabbit originally from a place called Ankara in Turkey. It is bred for its soft, light weight wool called angora wool. • Angora goat- Hair from the angora goat is used to make a shiny, silk like fibre called mohair. Mohair is used to make Sweaters, Coats and blankets
• Kasmir goat- The soft under wool of the kasmir goat is used to make fine Shawls • Alpaca and llama- The alpaca and llama are south American animals related to camels. We get soft and durable wool from them • Camel- Camel hair is very warm and used to make coat, sweaters, mufflers
• Musk OX- The musk ox is related to sheep and goat. It is found in Canada, Greenland • Yak- The yak is a large animals related to cows found in central Asia, Tibet, Mongolia and Russia. Yak wool is soft and warm and is used in cold places like Tibet and Kasmir
Wool Processing • Fleece has to undergo many processes before it can be made into yarn and fabric • Shearing- The process by which fleece is removed from the body of an animals is called Shearing. It is like giving the animal a haircut is done manually using rezors or shearing machine
Scouring and Drying • The Sheared wool has to trapped dust and other impurities Such as dead skin. It is thoroughly washed or scoured in hot water with detergents. The cleaned and washed wool is then dried • Grading- The cleaned fibre are sorted according to diameter, length, strength, colour. This is called grading
Carding • Scoured fleece is tangled and may contain small tufts of hair, seeds and straw. This fleece is therefore passed through rollers, which removed impurities and straighten and comb the fibre into thin sheet. This process is called carding. The sheet is passed through machines to get thin, long ropes called slivers
Spinning • The ropes are further stretched and twisted to get yarn, which is used to make cloths. This process is known as spinning • Dying and Blending- Wool can be dyed in different colour after it is scoured or after it is spun into yarn. Different kinds of fibres can be blended mechanically
Health Hazards in the wool Industry • Sheep can get a fatal bacterial disease called anthrax, which can spread to humans Through infected meat or wool and cause death. Earlier, this disease commonly infacted people who worked as sorters in wool industry. This disease is therefore called sorter’s disease. These days sheeps are reared in hygienic conditions and vaccinated on time. This has helped to almost completely stop the spread of sorter’s disease.
The History Of Silk • Silk is an animal fibre obtained from the cocoons of silkworms. It has a history of more than 4000 years. Silk Industry began in china • Silk is Soft, Smooth and lustrous. Silk fibres are very strong and obtained as long, continuous filaments. Silk has always been a costly luxury fabric.
The life cycle of Silk moth • The silk moth has many stages in its life cycle. A female silk moth lays 300 -400 tiny eggs. These eggs hatch into caterpillars called larva. The larvae which are 2 cm long, feed on leaves and grow in size • When a larva is ready to enter the next stage, it secrets a liquid from two salivary gland present on its head. This liquid solidifies into a fine fibre when it comes in contact with air.
The life cycle of the silk moth • Over the next few days, the larva spins fibre around itself, forming a silky case called a cocoon. At this stage of its life cycle, the silk moth is called a pupa. The pupa goes through dramatic changes inside the cocoon and comes out as an adult moth. This complete transformation in body shape from the larva form to the adult form is known as metamorphosis.
Silkworm rearing and Silk Processing • Raising silkworms for the commercial production of silk is called sericulture. The silkworm that is most commonly raised for this purpose is the mulberry silkworm, which feeds on mulberry leaves • Silkworm Rearing- Healthy female moth are chosen to lay eggs. The eggs are given enough warmth and humidity to ensure that they hatch into larvae. The larvae are transferred to trays and are fed mulberry leaves.
• After around six weeks, they stop eating and start spinning silk fibre around themselves. • Cocoon softening- After the larvae finish spinning the cocoon, the cocoons are immersed in boiling water. This kills the silkworms inside. This is done for two reason • 1. The silk moth does not leave the cocoon, thus breaking the fibre. • 2. The cocoon is softened and the fibre can be separated
Reeling and spinning • Reeling and spinning- The fibre is then unwound from the cocoon. This process of unwinding or taking out silk fibre from cocoon is called reeling. Reeling is done with the help of special machines. Reeled fibres are twisted and spun into silk thread or yarn. Weavers use this yarn to make silk fabric
Types of Silk • India also produces Eri silk, Muga silk, Tassar Silk and so on. Eri and Muga silk are produced in the north-east and tassar silk is produced in west Bengal.
Health Hazards in silk industry • Respiratory Diseases- Workers who remove silk fibre from cocoons inhale vapours, dust. This can cause respiratory diseases like asthma and bronchitis and also leads to allergies • Skin infections- The workers have to check cocoons to see whether the silk fibre has loosened enough for reeling by putting their hands in very hot water. This can cause to skin problems and peel off and can lead to wounds and skin infections
• Q-Which of the following fibres are plant fibres and which of them are animal fibre • Jute, Flex. Wool, silk, cotton • Q- What is the diet of sheep ? • Q-Give one word of the following • 1. The process of removing fleece from sheep • 2. Washing raw wool to remove dirt • 3. Categorising wool according to diameter, length and colour. • 4. Straightening and combing fibres into thin sheet • Q- What is anthrax?
Answer the questions on the life cycle of a silk moth • At which stage does the silkworm feed on leaves? • At which stage is the cocoon formed? • How is the cocoon formed? • What happened to the larva inside the cocoon? • What is Pupa? • What do you mean by metamorphisis?
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