An Overview of Silk Fibres: India Perspectives
M.Sc. in Fabric and Apparel Science
Delhi University, India
Natural Silk – Queen of Textiles
Natural silk is the nature’s bounty to the humankind unfolded in its finest and sensuous form. Silk is the most gorgeous fibre and also known worldwide as the queen of fibres. The enchanting sheen, amazing drape, enamoring feel and the affinity to radiating resplendence are its most distinct characteristics. The trance of natural silk has made our ancestors make it as a part of all religious rituals.
The effort to invent manufacturing of natural silk artificially has led to invention of host of fibres like nylon and rayon. The effort for an exact duplication of natural silk is still on, but the natural silk remains as the queen of textiles in all its glory.
Man is always inquisitive for silk products. SILK – The Queen of Textiles, spells luxury, elegance, class and comfort. Mankind has always loved this shimmering fibre of unparalleled grandeur from the moment Chinese Empress Shiling Ti discovered it in her teacup. It withstood many a daunting challenge from other natural and artificial fibres and yet, remained the undisputed Queen of Textiles since centuries. Exquisite qualities.
Like the natural sheen, inherent affinity for dyes and vibrant colours, high absorbance, light weight, resilience and excellent drape etc. have made silk, the irresistible and inevitable companion of the eve, all over the world.
Chemically speaking, silk is made of proteins secreted in the fluid state by a caterpillar, popularly known as ‘silkworm’. These silkworms feed on the selected food plants and spin cocoons as a ‘protective shell’ to perpetuate the life. Silkworm has four stages in its life cycle viz., egg, caterpillar, pupa and moth. Man interferes this life cycle at the cocoon stage to obtain the silk, a continuous filament of commercial importance, used in weaving of the dream fabric.
Origin of Silk – Legend of Lady Hsi-Ling-Shih
Chinese legend gives the title Goddess of Silk to Lady Hsi-Ling-Shih, wife of the mythical Yellow Emperor, who was said to have ruled China in about 3000 BC. She is credited with the introduction of silkworm rearing and the invention of the loom. Half a silkworm cocoon unearthed in 1927 from the loess soil astride the Yellow River in Shanxi Province, in northern China, has been dated between 2600 and 2300 BC. Another example is a group of ribbons, threads and woven fragments, dated about 3000 BC, and found at Qianshanyang in Zhejiang province. More recent archeological finds – a small ivory cup carved with a silkworm design and thought to be between 6000 and 7000 years old, and spinning tools, silk thread and fabric fragments from sites along the lower Yangzi River – reveal the origins of sericulture to be even earlier.
Silk Fibres Production
The making of silk is different from that of other natural fibres. There are many steps involved in silk fibres manufacturing.
- Cultivation of Cocoons (Sericulture)
- Filature Operations
- Manufacturing of Silk Yarns
- Finishing of Silk Fabrics
Sericulture has a long and colorful history unknown to most people. For centuries the West knew very little about silk and the people who made it. Pliny, the Roman historian, wrote in his Natural History in 70 BC “Silk was obtained by removing the down from the leaves with the help of water…”. For more than two thousand years the Chinese kept the secret of silk altogether to themselves. It was the most zealously guarded secret in history.
Manufacturing Process for Silk Yarns:
Silk is a fine translucent fibres produced from the silk worm. The manufacturing process of silk fibres starts with the rearing of cocoons. There are many varieties of the silk worm from which the silk fibres can be obtained. However, it is found that the fibre obtained from the larva of Bombyx mori is of commercial value. The process of obtaining silk fibres from Bombyx mori requires careful nourishment of the cocoons which is put through his pinning process.
The process of cultivating the silkworm for the production of raw silk is called as sericulture. Silk fibres is a continuous filament fibre consisting of the fibroin, which is connected together with the silk gum, sericin. This natural protein or fibroin is secreted from two salivary glands.
There are four stages in the life cycle of the moth which are as follows:
- The egg, which develops into a larva, or caterpillar–the silkworm
- The silkworm, which spins its cocoon for protection, to permit development into the pupa
- The pupa emerges from the cocoon as the moth.
- Female moth lays eggs, so continuing the lifecycle.
They may be hatched three times a year. The female moth lays around 350 to 400 eggs and the moths die soon after. As they are subject to hereditary infection, the eggs from infected moths are destroyed which results in to production of fine silk fibres. Larvae of about 3 mm are hatched from the eggs. For about 20 to 30 days, they are carefully nurtured and are fed five times a day on chopped mulberry leaves. Ideal temperature 23oC-27oC, humidity is 65%-80%. The silk moth lays eggs,
The flowing pathway is used to the production of silk fibres:
- Silk of moth caterpillars has been used for textile manufacture.
- When sexing pupae are used by identification of male and female pupae by looking at the back.
- Have to do sexing on 8th day after pupation. Then cut the cocoon do not separate cut top, and then place the cocoons in a box like drawer.
- Cover the box with tissue paper and two boxes separate male and female.
The silk-moths cannot fly because their bodies are too heavy in relation to their wings. Male’s silk-moths die soon after mating while one single female silk-moth lies from 300 to 500 tiny eggs before she dies. The eggs hatch into the silkworms in spring time and the complete cycle takes approximately about two months.
- In 11th day, just after emergence mating with male and female by both are coupling.
- Mating for about one day every 30 minutes ejaculate sperms.
- After 1 ½ hours. Because need three ejaculations.
- Silk moths lay eggs on specially prepared paper by using paper card method.
Chemical treatment of eggs
- Forma l dehyde treatment (2%)-When immersing eggs are disinfected.
- Acid treatment (1.1 5g HCl)-eggs are immersed for 5 minuets
- Washing in running water
- Air drying-keeping under the fan
- 1st day to 7thkeep the eggs rapped in a tissue paper.
- 8th day-black boxing, eggs are rapped with black paper or put in to black box to prevent irregular hatching.
- 11th day morning all the eggs are gray in color with dark spot.
- Expose eggs to light and then eggs are hatched around an hour.
- Silkworm are white but this stage black in ant stage
- Which hatch into an ant called as larva about 1/8 inches (3mm) in length.
- This can be done at breeding station or rearing station.
- Keep the eggs cards are rearing trays and removal of warms from egg shells/cards.
- Then giving 1stfeed (1cm strips of lender mulberry leaves). warms are very attractive to mulberry leaves because it contains citral.
Warm rearing station
- Increasing space
Feeding the larva
- The larva at this stage has voracious appetite and requires careful nourishment. They are fed 5 times a day on chopped mulberry leaves.
- After four changes of skin or molting the worm reaches full growth of about 3 ½ inches (9cm) long.
- At this stage the interest in the food ceases and is ready to spin its cocoon.
- The silkworm begins to secrete a protein like substance through a small opening under the caterpillar’s jaws which is called as the spinneret.
- The silk solidifies when it comes in contact with the air.
- On 3rd day, 20000 warms need 0.8 square meters.
- Stop feeding for about day 20 hours need molting.
- 4th day do not feed even feed even feed they do not eat. End of the 3rdmoulting management and maintain low RH.
- 5th day-2nd instars-spacing gradually increase.
- 7th day -molting management
- 8th day-3rdinstar, increase space, feeding mature leaves and cleaning
- 11th day -molting
- 12th day-4th instars
- 16th day-molting
- 17th day-27th day-5thinstar, branch feeding. This called flour rearing or table rearing.
- Pupation-On 27th day they leave the leaves and look for a corner to build a cocoon. Within twenty – four hours and in three days the cocoon is complete to a size and shape of a peanut shell.
- The filament is in the form of a double strand of fibroin, which is held together by a gummy substance called sericin, or silk gum.
- As this cutting through damages the cocoon, the filament cannot be unwound in one long thread. The life cycle is terminated at this point by a process known as stoving, or stifling.
- If left undisturbed, the pupae inside the cocoon develop into a moth within two weeks. To emerge, the moth breaks open the cocoon by secreting an alkaline liquid that dissolves the filament.
Processing & grading
- The silk yarn production begins with selecting for their quality.
- The cocoons will be sorted into normal and abnormal cocoons.
- The fresh cocoons normal are reelable to produce raw silk fibres but the abnormal cocoons are unreelable.
- The abnormal cocoons are double cocoons, perforated cocoons, internally and externally soiled cocoons, thin-end cocoons, thin-middle cocoons, malformed cocoons, etc.
After the first selection of cocoons:
- They have to be dried.
- The first goal of cocoon drying is the protection of cocoon quality, to preserve conditions for reeling cocoons and prevent damage that might be caused by long periods of storage.
- Drying kills the pupa and evaporates moisture that would otherwise ruin cocoons.
- Dried cocoon storage conditions are designed to keep the raw material for long periods without any damage from moulds and pests.
- Cocoon storage should preferably be built with double walls. Cloth or polyethylene bags are recommended as containers for dried cocoon storage.
- In most modern factories which aim at producing high-grade raw silk fibres, the cocoons are graded on visual inspection or by mechanical tests are actually mixed as in the required proportions. This is called cocoon mixing or blending and is done to ensure speed and uniformity of reeling as well as to obtain the desired effect in raw silk fibres.
- The reelable cocoons have then to undergo the reeling processing, after which they are either processed further to raw silk fibres or to throw silk. The unreelable silk is processed further to spun silk.
The technological process of silk reeling.
Silkworm and The Family
There are many indigenous varieties of wild silk moths found in a number of different countries. The key to understanding the great mystery and magic of silk, and China’s domination of its production and promotion, lies with one species: the blind, flightless moth, Bombyx mori. It lays 500 or more eggs in four to six days and dies soon after. The eggs are like pinpoints – one hundred of them weigh only one gram. From one ounce of eggs come about 30,000 worms which eat a ton of mulberry leaves and produce twelve pounds of raw silk fibres. The original wild ancestor of this cultivated species is believed to be Bombyx mandarina Moore, a silk moth living on the white mulberry tree and unique to China. The silkworm of this particular moth produces a thread whose filament is smoother, finer and rounder than that of other silk moths. Over thousands of years, during which the Chinese practiced sericulture utilizing all the different types of silk moths known to them, Bombyx mori evolved into the specialized silk producer it is today; a moth which has lost its power to fly, only capable of mating and producing eggs for the next generation of silk producers.
The Secret of Sericulture
Producing silk fibres is a lengthy process and demands constant close attention. To produce high quality silk fibres, there are two conditions which need to be fulfilled – preventing the moth from hatching out and perfecting the diet on which the silkworms should feed. Chinese developed secret ways for both.
The eggs must be kept at 65 degrees F, increasing gradually to 77 degrees at which point they hatch. After the eggs hatch, the baby worms feed day and night every half hour on fresh, hand-picked and chopped mulberry leaves until they are very fat. Also, a fixed temperature has to be maintained throughout. Thousands of feeding worms are kept on trays that are stacked one on top of another. A roomful of munching worms sounds like heavy rain falling on the roof. The newly hatched silkworm multiplies its weight 10,000 times within a month, changing color and shedding its whitish-gray skin several times.
The silkworms feed until they have stored up enough energy to enter the cocoon stage. While they are growing, they have to be protected from loud noises, drafts, strong smells such as those of fish and meat and even the odor of sweat. When it is time to build their cocoons, the worms produce a jelly-like substance in their silk glands, which hardens when it comes into contact with air. Silkworms spend three or four days spinning a cocoon around themselves until they look like puffy, white balls.
After eight or nine days in a warm, dry place the cocoons are ready to be unwound. First, they are steamed or baked to kill the worms, or pupas. The cocoons are then dipped into hot water to loosen the tightly woven filaments. These filaments are unwound onto a spool. Each cocoon is made up of a filament between 600 and 900 meters long! Between five and eight of these super-fine filaments are twisted together to make one thread.
Finally, the silk threads are woven into cloth or used for embroidery work. Clothes made from silk are not only beautiful and lightweight, they are also warm in cool weather and cool in hot weather.
Literary sources such as The Book of History, and The Book of Rites give further information about sericulture. Reeling silk and spinning were always considered household duties for women, while weaving and embroidery were carried out in workshops as well as the home. In every silk-producing province the daughters, mothers and grandmothers of every family devoted a large part of the day for six months in a year to the feeding, tending and supervision of silkworms and to the unraveling, spinning, weaving, dyeing and embroidering of silk. By the fifth century BC, at least six Chinese provinces were producing silk. Each spring, the empress herself inaugurated the silk-raising season, for silk fibres production was the work of women all over China. The technique and process of sericulture were guarded secrets and closely controlled by Chinese authorities. Anyone who revealed the secrets or smuggled the silkworm eggs or cocoons outside of China would be punished by death.
Silk Development in China
When silk was first discovered, it was reserved exclusively for the use of the ruler. It was permitted only to the emperor, his close relations and the very highest of his dignitaries. Within the palace, the emperor is believed to have worn a robe of white silk; outside, he, his principal wife, and the heir to the throne wore yellow, the color of the earth.
Gradually the various classes of society began wearing tunics of silk, and silk came into more general use. As well as being used for clothing and decoration, silk was quite quickly put to industrial use by the Chinese. This was something which happened in the West only in modern times. Silk, indeed, rapidly became one of the principal elements of the Chinese economy. Silk was used for musical instruments, fishing-lines, bowstrings, bonds of all kinds, and even rag paper, the world’s first luxury paper. Eventually even the common people were able to wear garments of silk.
During the Han Dynasty, silk ceased to be a mere industrial material and became an absolute value in itself. Farmers paid their taxes in grain and silk. Silk began to be used for paying civil servants and rewarding subjects for outstanding services. Values were calculated in lengths of silk as they had been calculated in pounds of gold. Before long, it was to become a currency used in trade with foreign countries. This use of silk continued during the Tang as well. It is possible that this added importance was the result of a major increase in production. It found its way so thoroughly into the Chinese language that 230 of the 5,000 most common characters of the mandarin “alphabet” have silk as their “key”.
A Secret Out to The World
In spite of their secrecy, however, the Chinese were destined to lose their monopoly on silk production. Sericulture reached Korea around 200 BC, when waves of Chinese immigrants arrived there. Silk reached the West through a number of different channels. Shortly after AD 300, sericulture traveled westward and the cultivation of the silkworm was established in India.
It is also said that in AD 440, a prince of Khotan (today’s Hetian) –a kingdom on the rim of Taklamakan desert — courted and won a Chinese princess. The princess smuggled out silkworm eggs by hiding them in her voluminous hairpiece. This was scant solace to the silk-hungry people of the West, for Khotan kept the secret too. Why share it with the westerners and kill a good market?
Then around AD 550, two Nestorian monks appeared at the Byzantine Emperor Justinian’s court with silkworm eggs hid in their hollow bamboo staves. Under their supervision the eggs hatched into worms, and the worms spun cocoons. Byzantium was in the silk business at last. The Byzantine church and state created imperial workshops, monopolizing production and keeping the secret to themselves. This allowed a silk industry to be established in the Middle East, undercutting the market for ordinary-grade Chinese silk. However high-quality silk textiles, woven in China especially for the Middle Eastern market, continued to bring high prices in the West, and trade along the Silk Road therefore continued as before. By the sixth century the Persians, too, had mastered the art of silk weaving, developing their own rich patterns and techniques. It was only in the 13th century—the time of the Second Crusades—that Italy began silk fibres production with the introduction of 2000 skilled silk weavers from Constantinople. Eventually silk production became widespread in Europe.
Silk and Its Trade
Silk became a precious commodity highly sought by other countries at a very early time, and it is believed that the silk trade was actually started before the Silk Road was officially opened in the second century BC. An Egyptian female mummy with silk has been discovered in the village of Deir el Medina near Thebes and the Valley of the Kings, dated 1070 BC, which is probably the earliest evidence of the silk trade. During the second century BC, the Chinese emperor, Han Wu Di’s ambassadors traveled as far west as Persia and Mesopotamia, bearing gifts including silks. A Han embassy reached Baghdad in AD 97, and important finds of Han silks have been made along the Silk Road. One of the most dramatic finds of Tang silks along the Silk Road was made in 1907 by Aurel Stein. Sometime around 1015, Buddhist monks, possibly alarmed by the threat of invasion by a Tibetan people, the Tanguts, sealed more than ten thousand manuscripts and silk paintings, silk banners, and textiles into a room at the Caves of the Thousand Buddhas near Dunhuang, a station on the Silk Road in north-west Gansu.
From about the fourth century BC, the Greeks and Romans began talking of Seres, the Kingdom of Silk. Some historians believe the first Romans to set eyes upon the fabulous fabric were the legions of Marcus Licinius Crassus, Governor of Syria. At the fateful battle of Carrhae near the Euphrates River in 53 BC, the soldiers were so startled by the bright silken banners of the Parthian troops that they fled in panic. Within decades Chinese silks became widely worn by the rich and noble families of Rome. The Roman Emperor Heliogabalus (AD 218 – 222) wore nothing but silk. By 380 AD, Marcellinus Ammianus reported, “The use of silk which was once confined to the nobility has now spread to all classes without distinction, even to the lowest.” The craving of silk continued to increase over the centuries. The price of silk was very hight in Rome. The best Chinese bark (a particular kind of silk) cost as much as 300 denarii (a Roman soldier’s salary for an entire year!). Many sources quote that Roman citizens’ demand for imported silks was so great as to be damaging to the Roman economy.
Silk was even beginning to have a civilizing effect on the barbarians. In 408 AD when Alaric, a Goth, besieged Rome, his price for sparing the city included 5000 pounds of gold, 3000 pounds of pepper, 30,000 pounds of silver and 4000 tunics of silk.
World silk production has approximately doubled during the last 30 years in spite of man-made fibres replacing silk for some uses. China and Japan during this period have been the two main producers, together manufacturing more than 50% of the world production each year. During the late 1970’s China, the country that first developed sericulture thousands of years ago dramatically increased its silk fibres production and has again become the world’s leading producer of silk.
Silks of India
Silk has been intermingled with the life and culture of the Indians. Though India is producing all the varieties of silk i.e., dress materials, scarves/stoles, readymade garments, etc., the silk sarees are unique. The saree is almost synonymous with the word silk. It is the traditional costume of Indian woman since time immemorial. There are innumerable references in Indian literature about this draped garment and the style of wearing differs from time to time, region to region and people to people. The silk sarees of India are among the living examples of the excellent craftsmanship of the weavers of the country.
The artistic and aesthetic sense of Indian weavers is not content with striking colours they choose for the fabrics, but lies in their mastery over the creation of floral designs, beautiful textures, fine geometry and the durability of such work. The weaver not only weaves with yarn but with intense feeling and emotion. In India, there are a number of silk weaving centers spread all over the country, known for their distinct and typical style and products. For Indians, particularly ladies, silk is lifeline – the elixir. Silk is always woven interwoven with way of life and culture of a region. Craftsmen all over the Indian sub-continent tried to master the weaving of sarees as exclusive as one can think of, putting motif designs, colours, pattern and versatility in them. No two sarees can be of same design left to the choice of weaver, thus there is innumerable pattern or diversity.
Over the years, specific centres sprung and developed to promote a particular pattern of design / weaving and they became distinct. Some of the famous silk centers in India are as under: –
|Sl no||State||Silk Centre|
|1||Andhra||Dharmavaram, Pochampalli, Venkatagiri, Narainpet|
|5||Jammu & Kashmir||Srinagar|
|6||Karnataka||Bangalore, Anekal, Ilkal, Molakalmuru, Melkote, Kollegal|
|7||Chattisgarh||Champa, Chanderi, Raigarh|
|9||Tamil Nadu||Kanchipuram, Arni, Salem, Kumbhakonam, Tanjavur|
|11||West Bengal||Bishnupur, Murshidabad, Birbhum|
The Brocades of Banaras
Situated on the banks of the holy river Ganges, Varanasi is famous for its finest silk sarees and brocades. These sarees are known for rich and intricately woven motifs of leaf, flowers, fruits, birds, etc. on a soft colour background. They are enriched with intricate borders and heavily decorated pallus. The centre is also known for its gauzi silver and gold tissues, which are ultra-light in weight and delicate. The kinkab of Banaras is legendary. It is a glittering weave of gold and silver threads. The pure silk with a touch of gold is called bafta and the finely woven brocade of variegated silk is known as Amru.
The tricks of tie and dye
The resist dyeing techniques has been practiced in India since centuries. There are two distinct traditions in this technique. The patola or ikat technique involves the dyeing of the tie-resist yarn. The bandhej or bandhini involves the dyeing of the fabric.
The ikats of Orissa
The tie and dye weaves of Orissa known as ikats employ the yarn resist method for both warp and weft with diffused effect. But the overall pattern is boldly articulated as in confident strikes of a brush. Both mulberry and tasar silks are used in the weaving of these ikats.
The Patolas of Gujarat
The patolas are known for their precision subtlety and beauty. Here, both warp and weft are dyed by dye resist method in a range of five or six traditional colours like red, indigo, blue, emerald green, black or yellow. The exact and highly skilled process ensures that when the fabric is woven, the design will appear precisely and create a magnificently coloured and figured ground of great richness and beauty with birds, flowers, animals, dancers, etc. in a geometrically stylized perfection.
The ballet of bandhej
In bandhej or bandhini, the finely woven fabric is knotted tightly and dyed to achieve a distinct design. The sarees, odhnis (veils) and turbans of these regions are a medley of brilliant colours. The bandhini of Kutch is unmatched for their fineness of the minutely tied knots, the magnificence of the colours and the perfect designs.
The Tanchois of Gujarat
The tanchoi brocade was named after the three Parsi brothers called choi who learnt this art in China and introduced it to Surat. The choi brocade is usually a dark satin weave, purple or dark red in ground colour, embellished with motifs of flowers, creepers, birds all over design.
The temple silks of the South
South India is the leading silk fibres producing area of the country also known for its famous silk weaving enclaves like Kancheepuram, Dharmavaram, Arni, etc. While the temple towns like Kancheepuram are renowned for their magnificent heavy silk sarees of bright colours with silver or gold zari works, the centers like Bangalore and Mysore are known for their excellent printed silks.
The traditional handloom silks always score over the power loom silks in the richness of their textures and designs, in their individuality, character and classic beauty. Handloom weaving remains a symbol of versatility and creativity of living craft. Today, Indian silks, especially the handloom products, remain the most beautiful and cherished the world over.
The states traditionally interested in sericulture development are Karnataka, Andhra Pradesh, West Bengal, Tamil Nadu, Assam, Manipur and Meghalaya. Karnataka accounts for 55.65 per cent of the silk yarn production of the country followed by Madhya Pradesh (40.48%), Tamil Nadu (2.42%) and Punjab (1.45%)
Karnataka is the largest producer of silk in the country. It produces only mulberry silk contributing about 41.4 per cent of the country’s output. Here mulberry cultivation occupies about 8,500 hectares of the agricultural land yielding about 68 lakh kg of raw silk annually. Bulk of the production comes from Bangalore, Mysore, Kolar, Mandya, Tumkur and Belgaum districts.
Channapatna and Mysore are the main centres of silk textiles. The state-owned Channapatna mill has a capacity of 6,000 spindles. The state hardly uses 40 per cent of the total yarn produced and the rest is sent to places like Varanasi Dharmavaram, Kancheepuram, Arani, Kumbakonam and Surat.
2. West Bengal
West Bengal contributes 9.08 per cent of the total silk fibres production of the country; most of it being of mulberry variety. The cultivation is spread over an area of 6,500 hectares mostly in Malda, Murshidabad, Birbhum, 24 Parganas, Haora and Bankura districts. There are more than 4,500 handlooms with important weaving centers at Bishnerpur, Baswa, Raghunathpurand Chak Islampur.
The reeling work is done on the traditional charkhas. The state has a silk conditioning house at Kolkata and a 100-basin filature at Madhu Ghat (Maldah district).
3. Andhra Pradesh
The state contributes 34.6 per cent the total silk production of the country. Sericulture is carried on in Chittoor, Warangal, Karimnagar, Vishakhapatnam and Anantapur districts. There is flourishing handloom silk industry in Mahbubnagar, Karimnagar, Warangal, Adilabad and Kurnool districts.
Bihar (including Jharkhand) is the largest tasar silk producing state of the country. It contributes about 0.8 per cent of the total silk output of the country. Bulk of the production comes from Palamau, Hazaribag, Bhagalpur and Ranchi districts. About 1.5 lakh persons are engaged in the sericulture. Bhagalpur is an important centre of the industry.
Assam specializes in the production of muga silk. Besides tasar and eri silk varieties is also produced providing employment to about 15 lakh persons. Sericulture is an important cottage industry. Bulk of the production comes from Goalpara, Kamrup, Barpeta, Nalbari and Nowgong districts of the Brahmaputra valley. The state has a flourishing handloom silk industry. A 3,000-spindle spun silk mill has been set up at Jagi Road to utilise the silk waste.
6. Tamil Nadu
Tamil Nadu is the fifth largest producer of raw silk (3%) in the country. The production mainly comes from Coimbatore, Dharmapuri, Nilgiris, Salem and Tirunelveli districts. The state has about 2,000 handlooms and produces about 2.4 per cent of the silk-yarn in the country.
7. Madhya Pradesh-Chhattisgarh
Although Madhya Pradesh (including Chhattisgarh) contributes less than 1 per cent of the total silk production of the country, it is the second largest tasar silk producer (25 per cent of India’s production) after Jharkhand. Bulk of this supply comes from Balaghat, Bastar, Bilaspur, Raigarh and Surguja districts. The state is also the second largest producer of silk yarn (3, 34,000 kgs in 2002-03 or 40 per cent of the country’s output) in India.
8. Jammu and Kashmir
The state produces about 100,000 kg of raw silk annually. Here climate is very favourable for the rearing of silk worms. Main producers are Anantnag, Baramula, Doda, Jammu, Riasi and Udhampur districts. The state has 1,030 handlooms and 148 powers looms. It mainly produces white plain silk called ‘tabby’.
Among other important producers of raw silk and silk goods mentions may be made of Uttar Pradesh (Mirzapur and Varanasi districts), Manipur, Meghalaya, Orissa (hill districts), Maharashtra (Bhandara, Nagpur, Pune, Sangli, Solapur districts), Punjab (Gurdaspur, Ludhiana, Amritsar, Hoshiarpur and Jalandhar districts), Nagaland, Himachal Pradesh and Arunachal Pradesh.
Types of Silks
Geographically, Asia is the main producer of silk fibres in the world and produces over 90 % of the total global output. Though there are over 40 countries on the world map of silk, bulk of it is produced in China and India, followed by Japan, Brazil and Korea. China is the leading supplier of silk to the world with an annual production of 81880 MT (2000). Out of Which the Mulberry raw silk product is 78080 MT.
India is the second largest producer of silk with 17550 MT (2001-02) and also the largest consumer of silk in the world. It has a strong tradition and culture bound domestic market of silk. In India, mulberry silk is produced mainly in the states of Karnataka, Andhra Pradesh, Tamil Nadu, Jammu & Kashmir and West Bengal, while the non-mulberry silks are produced in Jharkhand, Chattisgarh, Orissa and north-eastern states.
There are four major types of silk of commercial importance, obtained from different species of silkworms which in turn feed on a number of food plants. These are:
Except mulberry, other varieties of silks are generally termed as non-mulberry silks. India has the unique distinction of producing all these commercial varieties of silk.
The bulk of the commercial silk produced in the world comes from this variety and often silk generally refers to mulberry silk. Mulberry silk comes from the silkworm, Bombyx mori L. which solely feeds on the leaves of mulberry plant. These silkworms are completely domesticated and reared indoors. In India, the major mulberry silk producing states are Karnataka, Andhra Pradesh, West Bengal, Tamil Nadu and Jammu & Kashmir which together accounts for 92 % of country’s total mulberry raw silk production.
Tasar (Tussah) is copperish colour, coarse silk mainly used for furnishings and interiors. It is less lustrous than mulberry silk, but has its own feel and appeal. Tasar silk is generated by the silkworm, Antheraea mylitta which mainly thrive on the food plants Asan and Arjun. The rearings are conducted in nature on the trees in the open. In India, tasar silk is mainly produced in the states of Jharkhand, Chattisgarh and Orissa, besides Maharashtra, West Bengal and Andhra Pradesh. Tasar culture is the main stay for many a tribal community in India.
Oak Tasar: (also known as temperate tasar)
It is a finer variety of tasar generated by the silkworm, Antheraea proyeli J. in India which feed on natural food plants of oak, found in abundance in the sub-Himalayan belt of India covering the states of Manipur, Himachal Pradesh, Uttar Pradesh, Assam, Meghalaya and Jammu & Kashmir. China is the major producer of oak tasar in the world and this comes from another silkworm which is known as Antheraea pernyi. Oak is mainly used for furnishing, dress materials and sarees. Bomkai, Paithani, Ikkat (tie & dye) and Katki are some popular fabrics produced using tasar silks. Bafta is a popular blend of tasar and cotton. Shawls and mufflers are also produced using a blend of oak tasar and other natural fibers like wool, cotton, etc. Tasar silk is ideal for making jackets for men and women or traditional costumes like the ‘salwar-kurta’. This silk can be styled into beautiful dresses, stoles and scarves. Tasar fabric can also be printed, hand-painted, or, even embroidered into traditional sarees and beautiful dress-materials. In fact, in India, it is said that a bride’s trousseau is never complete without a saree made of Tasar Silk!
Also known as Endi or Errandi, Eri is a multivoltine silk spun from open-ended cocoons, unlike other varieties of silk. Eri silk is the product of the domesticated silkworm, Philosamia ricini that feeds mainly on castor leaves. Ericulture is a household activity practiced mainly for protein rich pupae, a delicacy for the tribal. Resultantly, the eri cocoons are open-mouthed and are spun. The silk is used indigenously for preparation of chaddars (wraps) for own use by these tribals. In India, this culture is practiced mainly in the north-eastern states and Assam. It is also found in Bihar, West Bengal and Orissa. Also known as endi or errandi, this silk is produced by the eri silkworm (Philosamia ricini). These worms feed mainly on Castor and Kesseru. As eri cocoons are open ended, the yarn is spun. Interestingly, in many parts of the North-East, eri cocoons are produced for their edible pupae and silk is the by-product. Elegantly designed eri shawls and chaddars are quite popular because of their thermal properties. They can be blended with cotton, wool, jute or even mulberry silk to create exotic fabrics for use in jackets, or suiting material, or for producing a variety of furnishings, making it an interior decorators delight.
This golden yellow colour silk is prerogative of India and the pride of Assam state. It is obtained from semi-domesticated multivoltine silkworm, Antheraea assamensis. These silkworms feed on the aromatic leaves of Som and Soalu plants and are reared on trees similar to that of tasar. Muga culture is specific to the state of Assam and an integral part of the tradition and culture of that state. The most expensive of silks, muga is intrinsically woven into the cultural traditions of the people of Assam. The vibrant Sualkuchi sarees and mekhla-chaddars are the traditional items made from muga silk. In recent times, fashion designers have found exciting prospects in using muga silk for developing new products and designs. Use of muga yarn as a substitute for ‘zari’ in sarees is finding favour with reputed weavers.
In khadi silk, the ratio of khadi and silk fabric is 50:50. This fabric requires dry cleaning. It shrinks about 3% after the first wash. It is quite an expensive fabric. Khadi silk provides a royal and rich look. The various types of apparels made from khadi silk are salwar kameez, kurta pajama, saris, dupattas, shirts, vest and jackets. Apparels like kurta, jacket, sari blouses require lining to be given to ensure its longetivity. Previously khadi was dyed in earthy color tones and was used to make traditional garments but now designers are experimenting by dyeing khadi with striking colors like limegreen, violet, baby pink, turquoise blue, etc. Stylish garments like miniskirts, halter neck tops, racer tops, tunics, etc. are made from khadi.
Khadi is hand woven and hand spun fabric which takes time to be made. It is mainly manufactured in rural areas of India. In previous times it was considered as the fabric for the poor rural workers & farmers. But wearing khadi is no more for the poor, many high-profile personalities and economically sound people prefer to wear it. It is considered as one of the most beautiful Indian fabric. The khadi wearer gets a royal and distinguishable look due to its fall and style. It symbolizes luxury and uniqueness.
Raw silk is produced by a coarse spinning process; it is less even and slightly knobbed. Raw silk is quite a gummy, sticky substance, so before separating the filaments the cocoons must be softened by immersion in hot water to loosen the gum. Raw silk is typically a short fiber silk recycled from spinning silk.
In the production of mulberry silk only a certain middle section of the cocoon can be unreeled for spinning silk. The waste silk is the raw silk and it has a smooth feel with some bumps and a low luster. A raw silk fabric may fool you into thinking that it is cotton or synthetic. The fabric has irregular surface with rough and nubbly appearance. The nubbly texture of the silk comes from the use of very short fibres (called “silk noil”) to weave the fabric.
The luster quality or dullness of the fabric depends upon the filler yarn. Noil is made from the short fibres left after combing and carding, so it does not shine like other silk fabrics. The fabric is stiff and dull and the sericin can attract dirt and odors.
Matka Silk is obtained from waste Mulberry silk by hand spinning without removing the gum (sericin). Cocoons required to produce Matka are mainly obtained from Karnataka and Kashmir but spinning is mostly done in the villages of Malda and Murshidabad districts in West Bengal by women by hand spinning.
Filaments of the cocoons of this silk from Bihar were originally unwound and plied together on a mud pot, or Matka ( Today, they are alikely to be reeled on a woman’s thigh). In India, Matka means “rough handloom silk fabric.” Matka comes from thick yarn spun from the silk worm and results in some irregularities in the fabric. Resembling tweed in texture, the irregularities are expected and considered unique. Matka sews very easily and is a thicker type of fabric, used for suits, jackets and furnishings. By adjusting the amount of yarn, Matka can be used for varying thicknesses and textures.
From the four basic categories of silks the other silk fabrics are made, which are:
- China Silk
- Organza silk
- Cotton silk
- Crepe silk
- Bracade silk
- Taffeta silk
- Thai silk
- Satin silk
- Blended silk
A mixture of silk cocoons, both long, smooth and short and rough yellow. It is reeled from double cocoons nested together. The finest dupioni silk is Italian, 2nd is Chinese, 3rd is Indian.
Jacquard weave, embossing effect and contrasting surface; brocade figures are raised above the surface of the cloth. Many times, of multiple colors. Designs may be geometric or pictorial.
Satin weave silk, crepe back, sometimes called “crepe backed satin”.
Transparent, soft, light
Crepe backed satin is also called satin-backed crepe because the fabric is reversible; one face has the matte, pebbly texture of crepe, and the other face has the smooth, shiny texture of satin.
Soft, warp rib silk with small, flat crosswise ribs.
Sheer crepe, heavier than chiffon; crinkly, pebbly surface; drapey; tightly twisted yarns; woven. Silk is more drapey than poly. Good quality – hand-wash with 1 tbs shampoo, dry flat, press light steam. Layout without nap, double thickness, using a tissue paperbase to which the fabric and pattern are pinned through. Needle sizes should be 60/8 to 65/9. Dry iron silk setting with mist.
Short fibers, sportier appearance, made from the innermost part of the cocoon.
Thin, stiff, plain weave; fairly transparent; comes in silk, poly, or rayon. Silk organza is of much higher quality. It doesn’t shrink, so you don’t need to preshrink. Machine washing and drying makes it softer; expect to dry clean finished garment.
Plain woven and thin, with a rough weave. A wild silk fabric which was originally hand-woven from hand-reeled Chinese tussah silk. It is woven raw, and then piece degummed. Current pongee silk is a relatively stiff, tightly woven fabric, in medium to heavy weights. Yarns are usually reeled wild silk, but sometimes white silk is used. Natural colors range from off-white to dark honey beige.
Dupioni type silk from the Shantung Province of China.
Plain weave of various weights, silk broadcloth is a crisp fabric.
Made of nubby yarn both length and cross wise, it has a plain weave. Silk linen comes in various weights, and has the look of linen with linen characteristics.
Satin is a weave that produces a shiny surface texture from floating yarns. Protect the fabric with a press cloth, and use a dry iron while pressing. Use superfine pins to avoid snagging surface yarns.
Plain weave with irregular thick/thin yarn, tussah has an uneven surface and color; it is sometimes called “raw silk”.
Textured silk made of short waste fibres. The waste fibres fall out when spun silk is made into yarn.
|Commercially exploited sericigenous insects of the world and their food plants|
|Common Name||Scientific Name||Origin||Primary Food Plant(s)|
|Mulberry Silkworm||Bombyx mori||China||Morus indica|
|Tropical Tasar Silkworm||Antheraea mylitta||India||Shorea robusta|
|Oak Tasar Silkworm||Antheraea proylei||India||Quercus incana|
Q. leuco tricophora
|Oak Tasar Silkworm||Antheraea frithi||India||Q. dealdata|
|Oak Tasar Silkworm||Antheraea compta||India||Q. dealdata|
|Oak Tasar Silkworm||Antheraea pernyi||China||Q. dendata|
|Oak Tasar Silkworm||Antheraea yamamai||Japan||Q. acutissima|
|Muga Silkworm||Antheraea assama||India||Litsea polyantha|
|Eri Silkworm||Philosamia ricini||India||Ricinus communis|
India occupies second place in the silk producing countries of the world. Mulberry acreage tripled between 1971-72 and 1992-93 from 1.04 lakh hectares to 3.4 lakh hectares, while the production of silk increased almost five-fold, from 3,000 tons in 1970-71 to 14,168 tons in 1992-93.
The area under mulberry was 3 lakh ha in 1996-97 against 2.89 lakh ha in 1995-96, with the output of raw silk being 14,126 tons against 13,909 tones previously. It was further higher at 16,319 tons in 2002-03. Mulberry accounts for 90% of the total production, followed by eri 8.06%, tasar 1.74% and muga silk 0.63%.
Efforts are being made by the Central Silk Board (CSB) to increase the area under mulberry cultivation by paying special attention to the development of sericulture in the north-eastern states. An integrated muga and eri sericulture development project has been launched at a cost of Rs.95 crores during the Ninth Plan. Completion of the project will result in the expansion of mulberry plantation to 7,500 acres to produce 77.64 tons of raw silk.
The World Bank is going to provide assistance for a project covering 17 states costing Rs. 165.6 crores. The objective of the project is to improve the quality of the Indian raw silk and introduce sericulture to areas in non-traditional states.
Silk statistics of India
|Production of silk (Total)||MT||16319||15742||16500||17305||18475|
|Production of silk fabrics||Rs./Crore||8280||8201||8870||9812||9240|
Source: DGCIS, Ministry of Commerce, Govt. of India.
Silk products are essential items of export to European countries, African countries and the Middle East. Although there has been shortfall in the quantity of export in recent years but the value has shown rising trends.
In 1990-91 the value of all exports was Rs.440.53 crores which reached the record high of Rs.937.54 crores in 1994.95. In the next year it fell down to Rs.846.08 crores in 1995-96 but recovered in subsequent years so as to reach Rs. 2294 crores in 2002-03. Silk textile exports constitute about three percent of total textile exports of the country.
Though the quantum-wise exports were lower by 16.3 percent, the unit value increased significantly between 1996-97 and 2002-03. Exports to Europe grew by 9.45 per cent to Rs. 364.19 crores from Rs. 298.49 crores, while those to Africa rose by 31.7 per cent to Rs. 18.46 crores from Rs. 14.02 crores. Germany, Singapore, USA, Hongkong. U.K., Saudi Arabia, Kuwait, Malaysia, Sri Lanka, Russia and eastern African countries are the main buyers of the Indian silk goods.
Raw silk is not an important item of India’s export; Instead India imports raw silk of superfine variety from China for making Kanjeevaram and Dharmavaram varieties of saries and quality silk products.
Competition from artificial silk is the main problem faced by the Indian silk industry. The artificial silk is cheaper and better in quality. Import of better quality and cheaper raw silk from China is also detrimental for indigenous sericulture. The fluctuation of prices of raw silk badly affects the growers and the silk industry. There is no systematic testing and grading of silk as in advanced countries like Japan. The industry needs supportive measures for modernization of silk power looms together with a curb on the import of silk fabrics.
The Central Silk Board (CSB) is formulating plans for extending the area under mulberry cultivation, improving quality and intensifying research- work. A project has been initiated with the assistance from the Japanese International Cooperation Agency (JICA) for evolving suitable mulberry varieties and bivoltine silk worm races, as also technology for rearing. The CSB is focusing special attention to the growth of the industry in the north-eastern region.
- Silk: production and export management – T.D.Koshy, Pg:240-266, 394-448
- Handbook of Silk Technology by Tamanna N. Sonwalker, pg:56-66,99-109
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Founder & Editor of Textile Learner. He is a Textile Consultant, Blogger & Entrepreneur. He is working as a textile consultant in several local and international companies. He is also a contributor of Wikipedia.