Silk

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Silk is a "natural" protein fiber, some forms of which can be woven into textiles. The best-known type of silk is obtained from cocoons made by the larvae of the silkworm Bombyx mori reared in captivity (sericulture). The shimmering appearance for which silk is prized comes from the fibres' triangular prism-like structure which allows silk cloth to refract incoming light at different angles.

Contents 1 Wild silks and other types of silk 2 History of silk use 2.1 China 2.2 Thailand 2.3 India 2.4 Mediterranean world 2.5 Islamic world 2.6 Medieval and modern Europe 2.7 North America 3 Animal rights 4 Other uses 5 See also 6 References 7 External links 7.1 The End

[edit] Wild silks and other types of silk

"Wild silks" are produced by caterpillars other than the mulberry silkworm (Bombyx mori). The term "wild" implies that they are not capable of being domesticated and artificially cultivated like Bombyx mori. A variety of wild silks have been known and used in China, India, Vietnam, and Europe from early times, although the scale of production has always been far smaller than that of cultivated silks. Aside from differences in colours and textures, they all differ in one major aspect from the domesticated varieties: the cocoons that are gathered in the wild have usually already been damaged by the emerging moth before the cocoons are gathered, and thus the single thread that makes up the cocoon has been torn into shorter lengths. Commercially reared silkworm pupae are killed before the adult moths emerge by dipping them in boiling water or piercing them with a needle, thus allowing the whole cocoon to be unravelled as one continuous thread. This allows a much stronger cloth to be woven from the silk. Wild silks also tend to be more difficult to dye than silk from the cultivated silkworm.

There is some evidence that small quantities of wild silk were already being produced in the Mediterranean area and the Middle East by the time the superior, and stronger, cultivated silk from China began to be imported (Hill 2003, Appendix C).

Many different types of silk are produced by a huge variety of different types of insect (other than moth caterpillars), yet none of these have been exploited for commercial purposes, though there is basic research into the structures of such silks, as there is some variation at the molecular level. It is most commonly produced by larvae, and thus largely limited to insects with complete metamorphosis, but in some cases it is produced by adult insects such as webspinners. Silk production is especially common in the Hymenoptera (bees, wasps, and ants), and is sometimes used in nest construction. Other types of arthropod produce silk, most notably various arachnids such as spiders (see spider silk).

[edit] History of silk use

[edit] China

Silk fabric was first developed in ancient China, possibly as early as 6000 BC^{[citation needed]} and definitely by 3000 BC^{[citation needed]}. Legend gives credit to a Chinese empress, Xi Ling-Shi (Hsi-Ling-Shih, Lei-Tus). Though first reserved for the Emperors of China, its use spread gradually through Chinese culture both geographically and socially. From there, silken garments began to reach regions throughout Asia. Silk rapidly became a popular luxury fabric in the many areas accessible to Chinese merchants, because of its texture and lustre. But if someone told the secret of how to make the silk into yarn they were sentenced to death. Because of the high demand for the fabric, silk was one of the staples of international trade prior to industrialization. Also, the demand for silk in Europe was so high that silk was worth it's weight in gold.

Perhaps the first evidence of the silk trade is that of an Chinese empress of 1070 BCE. Ultimately the silk trade reached as far as the Indian subcontinent, the Middle East, Europe, and North Africa. This trade was so extensive that the major set of trade routes between Europe and Asia has become known as the Silk Road.

The Emperors of China strove to keep the knowledge of sericulture secret from other nations, in order to maintain the Chinese monopoly on its production. This effort had mixed success. Sericulture reached Korea around 200 BC, about the first half of the 1st century CE in ancient Khotan (Hill 2003, Appendix A), and by CE 300 the practice had been established in India.

[edit] Thailand

Silk from Thailand is produced by two types of silkworms: the Bombycidae (cultured silkworms) and Saturniidae (wild silkworms). Due to Thailand’s favorable climate, it is a year-round activity. Silk is mostly made by villagers from the central and northeast parts of the country who devote their time after the rice harvest to produce silk. Women traditionally weave silk on hand looms and pass the skill on to their daughters, as weaving is also a sign of maturity and eligibility for marriage. Thai silk generally uses complicated patterns in various colours and styles. Most regions of Thailand have their own typical silks, of which Mud-Mee, Tin Chok and Phrae Wa are considered some of the best.

[edit] India

Silk, known as pattu, has a long history in India and is widely produced today. Historically silk was used by the upper classes, while cotton was used by the poorer classes. Today silk is mainly produced in Kanchipuram, Dharmavaram, Mysore, etc. in South India and Banaras in the North. "Murshidabad silk", famous from historical times, is mainly produced in Malda and Murshidabad district of West Bengal and woven with hand looms in Birbhum and Murshidabad district. The silk from Kanchi is particularly well-known for its classic designs and enduring quality. The silk is traditionally hand-woven and hand-dyed and usually also has silver threads woven into the cloth. Most of this silk is used to make saris. The saris usually are very expensive and vibrant in color. Garments made from silk form an integral part of Indian weddings and other celebrations. In the northeastern state of Assam, three different types of silk are produced, collectively called Assam silk: Muga, Eri and Pat silk. Muga, the golden silk, and Eri are produced by silkworms that are native only to Assam. The heritage of silk rearing and weaving is very old and continues today especially with the production of Muga and Pat riha and mekhela sador, the three-piece silk saris woven with traditional motifs.

[edit] Mediterranean world

The Roman Empire knew of and traded in silk. During the reign of emperor Tiberius, sumptuary laws were passed that tried to forbid men from wearing silk garments but these proved ineffectual.^[1] Despite the popularity of silk, the secret of silk-making was only to reach Europe around CE 550, via the Byzantine Empire. Legend has it that monks working for the emperor Justinian smuggled silkworm eggs to Constantinople in hollow canes. The Byzantines were as secretive as the Chinese, and for many centuries the weaving and trading of silk fabric was a strict imperial monopoly^{[citation needed]}; all top-quality looms and weavers were located inside the Palace complex in Constantinople and the cloth produced was used in imperial robes or in diplomacy, as gifts to foreign dignitaries. The remainder was sold at exorbitant prices.

[edit] Islamic world

In Islamic teachings, Muslim men are forbidden to wear silk. Many religious jurists believe the reasoning behind the prohibition lies in avoiding clothing for men that can be feminine or extravagant and luxurious.^[2] Furthermore, Islam also prohibits the slaughter of animals for "sport" or "luxuries", hence the Islamic prohibition against the use of silk.^[3] Despite injunctions against silk, it retained its popularity. The Muslim Moors brought silk with them to Spain during their conquest of the Iberian Peninsula.

[edit] Medieval and modern Europe

Venetian merchants traded extensively in silk and encouraged silk growers to settle in Italy. By the 13th century, Italian silk was a significant source of trade. Since that period, the silk worked in the province of Como has been the most valuable silk in the world. The wealth of Florence was largely built on textiles, both wool and silk, and other cities like Lucca also grew rich on the trade. Italian silk was so popular in Europe that Francis I of France invited Italian silkmakers to France to create a French silk industry, especially in Lyon. Mass emigration (especially of Huguenots) during periods of religious dispute had seriously damaged French industry and introduced these various textile industries, including silk, to other countries. James I attempted to establish silk production in England, purchasing and planting 100,000 mulberry trees, some on land adjacent to Hampton Court Palace, but they were of a species unsuited to the silk worms and the attempt failed. Production started elsewhere later. In Italy, the Stazione Bacologica Sperimentale was founded in Padua in 1871 to research sericulture. In the late 19th century, China, Japan and Italy were the major producers of silk.^{[citation needed]} The most important cities for silk production in Italy were Como and Meldola (Forlì).

Silk was expensive in Medieval Europe and used only by the rich. Italian merchants like Giovanni Arnolfini became hugely wealthy trading it to the Courts of Northern Europe.

[edit] North America

James I of England introduced silk-growing to the American colonies around 1619, ostensibly to discourage tobacco planting. Only the Shakers in Kentucky adopted the practice. In the 1800s a new attempt at a silk industry began with European-born workers in Paterson, New Jersey, and the city became a US silk centre, although Japanese imports were still more important.

World War II interrupted the silk trade from Japan. Silk prices increased dramatically, and US industry began to look for substitutes, which led to the use of synthetics like nylon. Synthetic silks have also been made from lyocell, a type of cellulose fibre, and are often difficult to distinguish from real silk (see spider silk for more on synthetic silks).

[edit] Animal rights

Since the process of harvesting the silk from the cocoon kills the larvae, silk-culture has recently come under criticism from some animal rights activists. They cite the fact that the process kills many silkworms and also that artificial silks are available.^[4]

[edit] Other uses

In addition to clothing manufacture and other handicrafts, silk is also used for items like parachutes, bicycle tires, comforter filling and artillery gunpowder bags. Early bulletproof vests were also made from silk in the era of blackpowder weapons until roughly World War I. Silk undergoes a special manufacturing process to make it suitable for use as non-absorbable surgical sutures. Chinese doctors have also used it to make prosthetic arteries. Silk cloth is also used as a material to write on.

Mongols used silk as part of the under-armor garments. Silk is so tough that it was actually used as very light armor, although its special use (the big secret) was to stop arrow penetration into the body. The silk would stop an arrow from penetrating far enough into the body to be lethal; and the arrow could then be pulled out of the wound by tugging on the unbroken silk. The added advantage to this is that there would be no contact between the arrowhead and the interior of the body; thus it reduces the incidence of infected wounds.^{[citation needed]}

[edit] See also

• Mommes, the traditional density unit for silk.
• Rayon
• Silk Road
• Spider silk (with a discussion of synthetic silk)
• Jim Thompson, pioneer of Thailand's silk industry.
• Rajshahi Silk, famous silk clothing (especially saree) of Bangladesh
• Silk in the Indian subcontinent

[edit] References

1. ^ Tacitus. Annals. 
2. ^ Silk: Why It Is Haram for Men (2003-09-23). Retrieved on 2007-01-06.
3. ^ Animals in Islam. Retrieved on 2007-01-06.
4. ^ Down and Silk: Birds and Insects Exploited for Fabric. PETA. Retrieved on 2007-01-06.

• Good, Irene. 1995. “On the question of silk in pre-Han Eurasia” Antiquity Vol. 69, Number 266, December 1995, pp. 959-968
• Hill, John E. (2003), The Western Regions according to the Hou Hanshu (a translation of the Hou Hanshu)
• Hill, John E. 2004. The Peoples of the West from the Weilue 魏略 by Yu Huan 魚豢: A Third Century Chinese Account Composed between 239 and 265 CE. Draft annotated English translation. Appendix E. [1]
• Kuhn, Dieter. 1995. “Silk Weaving in Ancient China: From Geometric Figures to Patterns of Pictorial Likeness.” Chinese Science 12 (1995): pp. 77-114.
• Liu, Xinru. 1996. Silk and Religion: An Exploration of Material Life and the Thought of People, AD 600-1200. Oxford University Press.
• Sung, Ying-Hsing. 1637. Chinese Technology in the Seventeenth Century - T'ien-kung K'ai-wu. Translated and annotated by E-tu Zen Sun and Shiou-chuan Sun. Pennsylvania State University Press, 1966. Reprint: Dover, 1997. Chap. 2. Clothing materials.

[edit] External links

• Silkworm rearing (with photos)
• Silk embroidery
• References to silk by Roman and Byzantine writers
• Silk production and handloom weaving
• Comparison of Silks for Embroidery - article with photos comparing different silks used in hand embroidery
• Silk Sarees

[edit] The End