76-398: Silk is a natural protein fiber , some forms of which can be woven into textiles . The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons . The best-known silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity ( sericulture ). The shimmering appearance of silk is due to
152-399: A bave . Bave diameters for tussah silk can reach 65 μm. See cited reference for cross-sectional SEM photographs. Silk has a smooth, soft texture that is not slippery, unlike many synthetic fibers . Silk is one of the strongest natural fibers, but it loses up to 20% of its strength when wet. It has a good moisture regain of 11%. Its elasticity is moderate to poor: if elongated even
228-412: A degree of cost and challenge to creating a load bearing cellulose or other filler based nanocomposite. Natural fibers often show promise as biomaterials in medical applications. Chitin is notable in particular and has been incorporated into a variety of uses. Chitin based materials have also been used to remove industrial pollutants from water, processed into fibers and films, and used as biosensors in
304-414: A family of protein that support and strengthen many tissues in the body. Keratin is a structural protein located at the hard surfaces in many vertebrates. Keratin has two forms, α-keratin and β-keratin , that are found in different classes of chordates. The naming convention for these keratins follows that for protein structures: alpha keratin is helical and beta keratin is sheet-like. Alpha keratin
380-643: A keratin based implant, has the potential to be recognized as natural tissue by the body. This can lead either to integration in rare cases where the structure of the implant promotes regrowth of tissue with the implant forming a superstructure or degradation of the implant in which the backbones of the proteins are recognized for cleavage by the body. 23. Kuivaniemi, Helena, and Gerard Tromp. "Type III collagen (COL3A1): Gene and protein structure, tissue distribution, and associated diseases." Gene vol. 707 (2019): 151-171. doi:10.1016/j.gene.2019.05.003 Demineralizing (silk worm cocoon) Demineralizing has
456-422: A large satin waistcoat with flaps, were got up, of which the silk was perfect, but the lining entirely gone ... from the thread giving way ... No articles of dress of woollen cloth have yet been found.' Silk is a poor conductor of electricity and thus susceptible to static cling . Silk has a high emissivity for infrared light, making it feel cool to the touch. Unwashed silk chiffon may shrink up to 8% due to
532-737: A long history of a formative textile industry in ancient China, this find of silk textiles employing "complicated techniques" of weaving and dyeing provides direct evidence for silks dating before the Mawangdui -discovery and other silks dating to the Han dynasty (202 BC – 220 AD). Silk is described in a chapter of the Fan Shengzhi shu from the Western Han (202 BC – 9 AD). There is a surviving calendar for silk production in an Eastern Han (25–220 AD) document. The two other known works on silk from
608-413: A new silk industry in areas which have not the conditions or infrastructure for raising the domesticated silk worm Bombyx mori , possibly generating a revolutionary new income stream. An aqueous 1 M solution of ethylenediaminetetraacetic acid (EDTA) is used adjusted to pH 10 with saturated sodium hydroxide solution. The cocoons are immersed in this solution for 72 h at 40 °C and gently stirred. During
684-469: A number of issues, including, for instance, the permissibility of wearing silk neckties , which are masculine articles of clothing. In the Odyssey , 19.233, when Odysseus, while pretending to be someone else, is questioned by Penelope about her husband's clothing, he says that he wore a shirt "gleaming like the skin of a dried onion" (varies with translations, literal translation here) which could refer to
760-439: A number of small firms and cooperatives emerged. Among the most prominent of these was the cooperative utopian Northampton Association for Education and Industry, of which Sojourner Truth was a member. Following the destructive Mill River Flood of 1874 , one manufacturer, William Skinner , relocated his mill from Williamsburg to the then-new city of Holyoke . Over the next 50 years he and his sons would maintain relations between
836-505: A relaxation of the fiber macrostructure, so silk should either be washed prior to garment construction, or dry cleaned . Dry cleaning may still shrink the chiffon up to 4%. Occasionally, this shrinkage can be reversed by a gentle steaming with a press cloth. There is almost no gradual shrinkage nor shrinkage due to molecular-level deformation. Natural fiber Natural fibers or natural fibres (see spelling differences ) are fibers that are produced by geological processes , or from
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#1732766100578912-417: A small amount, it remains stretched. It can be weakened if exposed to too much sunlight. It may also be attacked by insects, especially if left dirty. One example of the durable nature of silk over other fabrics is demonstrated by the recovery in 1840 of silk garments from a wreck of 1782 : 'The most durable article found has been silk; for besides pieces of cloaks and lace, a pair of black satin breeches, and
988-401: A strong interface between the matrix and filler is required to achieve favorable mechanical properties. If this is not the case, the phases tend to separate along the weak interface and makes for very poor mechanical properties. In a MCC composite however this is not the case, if the interaction between the filler and matrix is stronger than the filler-filler interaction the mechanical strength of
1064-554: A tensile strength of approximately 200MPa. This tensile strength is an order of magnitude higher than human nails (20MPa), because human hair's keratin filaments are more aligned. Natural fibers tend to have decreased stiffness and strength compared to synthetic fibers. Properties also decrease with the age of the fiber. Younger fibers tend to be stronger and more elastic than older ones. Many natural fibers exhibit strain rate sensitivity due to their viscoelastic nature. Bone contains collagen and exhibits strain rate sensitivity in that
1140-416: A white-colored silk thread with no mineral on the surface. The pupae are killed by either dipping them in boiling water before the adult moths emerge or by piercing them with a needle. These factors all contribute to the ability of the whole cocoon to be unravelled as one continuous thread, permitting a much stronger cloth to be woven from the silk. Wild silks also tend to be more difficult to dye than silk from
1216-508: Is composed mostly of beta-sheets , due to a 59-mer amino acid repeat sequence with some variations. The flat surfaces of the fibrils reflect light at many angles, giving silk a natural sheen. The cross-section from other silkworms can vary in shape and diameter: crescent-like for Anaphe and elongated wedge for tussah . Silkworm fibers are naturally extruded from two silkworm glands as a pair of primary filaments (brin), which are stuck together, with sericin proteins that act like glue , to form
1292-546: Is concentrated in the Coimbatore , Erode , Bhagalpuri , Tiruppur , Salem , and Dharmapuri districts. Hyderabad , Andhra Pradesh , and Gobichettipalayam , Tamil Nadu , were the first locations to have automated silk reeling units in India. In the northeastern state of Assam , three different types of indigenous variety of silk are produced, collectively called Assam silk : Muga silk , Eri silk and Pat silk . Muga,
1368-855: Is cotton for textiles. Natural fibers are also used in composite materials, much like synthetic or glass fibers. These composites, called biocomposites, are a natural fiber in a matrix of synthetic polymers. One of the first biofiber-reinforced plastics in use was a cellulose fiber in phenolics in 1908. Usage includes applications where energy absorption is important, such as insulation, noise absorbing panels, or collapsable areas in automobiles. Natural fibers can have different advantages over synthetic reinforcing fibers. Most notably they are biodegradable and renewable. Additionally, they often have low densities and lower processing costs than synthetic materials. Design issues with natural fiber-reinforced composites include poor strength (natural fibers are not as strong as glass fibers) and difficulty with actually bonding
1444-448: Is found in mammalian hair, skin, nails, horn and quills, while beta keratin can be found in avian and reptilian species in scales, feathers , and beaks. The two different structures of keratin have dissimilar mechanical properties, as seen in their dissimilar applications. The relative alignment of the keratin fibrils significantly impacts the mechanical properties. In human hair the filaments of alpha keratin are highly aligned, giving
1520-780: Is markedly different from that of its bulk constituent. In regards to natural fibers, some of the best example of nanocomposites appear in biology. Bone , abalone shell , nacre , and tooth enamel are all nanocomposites. As of 2010, most synthetic polymer nanocomposites exhibit inferior toughness and mechanical properties compared to biological nanocomposites. Completely synthetic nanocomposites do exist, however nanosized biopolymers are also being tested in synthetic matrices. Several types of protein based, nanosized fibers are being used in nanocomposites. These include collagen, cellulose, chitin and tunican. These structural proteins must be processed before use in composites. To use cellulose as an example, semicrystalline microfibrils are sheared in
1596-581: Is now part of Malaysia , a second generation of silkworm was being imported as early as 1764 for the country's silk textile industry, especially songket . However, since the 1980s, Malaysia is no longer engaged in sericulture but does plant mulberry trees. In Vietnamese legend, silk appeared in the first millennium AD and is still being woven today. The process of silk production is known as sericulture . The entire production process of silk can be divided into several steps which are typically handled by different entities. Extracting raw silk starts by cultivating
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#17327661005781672-530: Is potentially large when compared with other natural fibers. A life-cycle assessment of Indian silk production shows that the production process has a large carbon and water footprint, mainly due to the fact that it is an animal-derived fiber and more inputs such as fertilizer and water are needed per unit of fiber produced. Silk fibers from the Bombyx mori silkworm have a triangular cross section with rounded corners, 5–10 μm wide. The fibroin-heavy chain
1748-414: Is soaked in extremely cold water and bleached before dyeing to remove the natural yellow coloring of Thai silk yarn. To do this, skeins of silk thread are immersed in large tubs of hydrogen peroxide . Once washed and dried, the silk is woven on a traditional hand-operated loom. The Rajshahi Division of northern Bangladesh is the hub of the country's silk industry. There are three types of silk produced in
1824-590: Is the presence of the silk protein fibroin in soil samples from two tombs at the neolithic site Jiahu in Henan , which date back about 8,500 years. The earliest surviving example of silk fabric dates from about 3630 BC, and was used as the wrapping for the body of a child at a Yangshao culture site in Qingtaicun near Xingyang , Henan. Legend gives credit for developing silk to a Chinese empress, Leizu (Hsi-Ling-Shih, Lei-Tzu). Silks were originally reserved for
1900-477: Is the second largest producer of silk in the world after China. About 97% of the raw mulberry silk comes from six Indian states, namely, Andhra Pradesh , Karnataka , Jammu and Kashmir , Tamil Nadu , Bihar , and West Bengal . North Bangalore, the upcoming site of a $ 20 million "Silk City" Ramanagara and Mysore , contribute to a majority of silk production in Karnataka. In Tamil Nadu , mulberry cultivation
1976-591: Is the world's second most abundant natural polymer , with collagen being the first. It is a "linear polysaccharide of β-(1-4)-2-acetamido-2-deoxy-D-glucose". Chitin is highly crystalline and is usually composed of chains organized in a β sheet. Due to its high crystallinity and chemical structure, it is insoluble in many solvents. It also has low toxicity in the body and is inert in the intestines. Chitin also has antibacterial properties. Chitin forms crystals that make fibrils that become surrounded by proteins. These fibrils can bundle to make larger fibers that contribute to
2052-483: Is used in biomedical applications. Collagen is a structural protein, often referred to as "the steel of biological materials". There are multiple types of collagen: Type I (comprising skin, tendons and ligaments, vasculature and organs, as well as teeth and bone and artery walls); Type II (a component in cartilage); Type III (often found in reticular fibers ); and others. Collagen has a hierarchical structure, forming triple helices, fibrils , and fibers. Collagen are
2128-634: The Great 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 very high prices. Italy was the most important producer of silk during the Medieval age. The first center to introduce silk production to Italy was the city of Catanzaro during the 11th century in the region of Calabria . The silk of Catanzaro supplied almost all of Europe and
2204-730: The Torah , a scarlet cloth item called in Hebrew "sheni tola'at" שני תולעת – literally "crimson of the worm" – is described as being used in purification ceremonies, such as those following a leprosy outbreak (Leviticus 14), alongside cedar wood and hyssop ( za'atar ). Eminent scholar and leading medieval translator of Jewish sources and books of the Bible into Arabic , Rabbi Saadia Gaon , translates this phrase explicitly as "crimson silk" – חריר קרמז حرير قرمز. In Islamic teachings, Muslim men are forbidden to wear silk. Many religious jurists believe
2280-519: The Yayoi period . The silk industry was dominant from the 1930s to 1950s, but is less common now. Silk from East Asia had declined in importance after silkworms were smuggled from China to the Byzantine Empire. However, in 1845, an epidemic of flacherie among European silkworms devastated the silk industry there. This led to a demand for silk from China and Japan , where as late as
2356-481: The cotton plant, for example, produce fabrics that are light in weight, soft in texture, and which can be made in various sizes and colors. Clothes made of natural fibers such as cotton are often preferred over clothing made of synthetic fibers by people living in hot and humid climates. Animal fibers generally comprise proteins such as collagen , keratin and fibroin ; examples include silk , sinew , wool , catgut , angora , mohair and alpaca . Chitin
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2432-475: The 12th century. Other Italian cities involved in silk production were Genoa , Venice , and Florence . The Piedmont area of Northern Italy became a major silk producing area when water-powered silk throwing machines were developed. The Silk Exchange in Valencia from the 15th century—where previously in 1348 also perxal ( percale ) was traded as some kind of silk—illustrates the power and wealth of one of
2508-595: The 17th century. 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. In 1732 John Guardivaglio set up a silk throwing enterprise at Logwood mill in Stockport ; in 1744, Burton Mill was erected in Macclesfield ; and in 1753 Old Mill
2584-643: The American silk industry and its counterparts in Japan, and expanded their business to the point that by 1911, the Skinner Mill complex contained the largest silk mill under one roof in the world, and the brand Skinner Fabrics had become the largest manufacturer of silk satins internationally. Other efforts later in the 19th century would also bring the new silk industry to Paterson, New Jersey , with several firms hiring European-born textile workers and granting it
2660-586: The Chinese monopoly . Nonetheless, sericulture reached Korea with technological aid from China around 200 BC, the ancient Kingdom of Khotan by AD 50, and India by AD 140. In the ancient era, silk from China was the most lucrative and sought-after luxury item traded across the Eurasian continent, and many civilizations, such as the ancient Persians, benefited economically from trade. Archaeological evidence indicates that sericulture has been practiced since
2736-566: The Chinese word "sī" and other Asian sources—compare Mandarin sī "silk", Manchurian sirghe , Mongolian sirkek . The production of silk originated in China in the Neolithic period, although it would eventually reach other places of the world ( Yangshao culture, 4th millennium BC). Silk production remained confined to China until the Silk Road opened at some point during
2812-647: The Han period are lost. The first evidence of the long distance silk trade is the finding of silk in the hair of an Egyptian mummy of the 21st dynasty, c.1070 BC. 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 came to be known as the Silk Road . The emperors of China strove to keep knowledge of sericulture secret to maintain
2888-633: The Japanese silk industry and its position as the lead silk exporter of the world. Today, China exports the largest volume of raw silk in the world. Silk has a long history in India. It is known as Resham in eastern and north India, and Pattu in southern parts of India . Recent archaeological discoveries in Harappa and Chanhu-daro suggest that sericulture , employing wild silk threads from native silkworm species, existed in South Asia during
2964-527: The Middle East by Peter Gaddum . Wild silk taken from the nests of native caterpillars was used by the Aztecs to make containers and as paper. Silkworms were introduced to Oaxaca from Spain in the 1530s and the region profited from silk production until the early 17th century, when the king of Spain banned export to protect Spain's silk industry. Silk production for local consumption has continued until
3040-413: The acetylated composition of the copolymer is below 50% it is chitosan. Chitosan is a semicrystalline "polymer of β-(1-4)-2-amino-2-deoxy-D-glucose". One difference between chitin and chitosan is that chitosan is soluble in acidic aqueous solutions. Chitosan is easier to process that chitin, but it is less stable because it is more hydrophilic and has pH sensitivity. Due to its ease of processing, chitosan
3116-551: The amorphous region, resulting in microcrystalline cellulose (MCC). These small, crystalline cellulose fibrils are at this points reclassified as a whisker and can be 2 to 20 nm in diameter with shapes ranging from spherical to cylindrical. Whiskers of collagen, chitin, and cellulose have all be used to make biological nanocomposites. The matrix of these composites are commonly hydrophobic synthetic polymers such as polyethylene, and polyvinyl chloride and copolymers of polystyrene and polyacrylate. Traditionally in composite science
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3192-984: The bodies of plants or animals . They can be used as a component of composite materials, where the orientation of fibers impacts the properties. Natural fibers can also be matted into sheets to make paper or felt . The earliest evidence of humans using fibers is the discovery of wool and dyed flax fibers found in a prehistoric cave in the Republic of Georgia that date back to 36,000 BP . Natural fibers can be used for high-tech applications, such as composite parts for automobiles and medical supplies. Compared to composites reinforced with glass fibers , composites with natural fibers have advantages such as lower density, better thermal insulation , and reduced skin irritation. Further, unlike glass fibers, natural fibers can be broken down by bacteria once they are no longer used. Natural fibers are good water absorbents and can be found in various textures. Cotton fibers made from
3268-422: The chitin fibers contribute to their hierarchical structure. In nature, pure chitin (100% acetylation ) does not exist. It instead exists as a copolymer with chitin's deacetylated derivative, chitosan. When the acetylized composition of the copolymer is over 50% acetylated it is chitin. This copolymer of chitin and chitosan is a random or block copolymer. Chitosan is a deacetylated derivative of chitin. When
3344-406: The composite is noticeably decreased. Difficulties in natural fiber nanocomposites arise from dispersity and the tendency small fibers to aggregate in the matrix. Because of the high surface area to volume ratio the fibers have a tendency to aggregate, more so than in micro-scale composites. Additionally secondary processing of collagen sources to obtain sufficient purity collagen micro fibrils adds
3420-481: The cultivated silkworm. A technique known as demineralizing allows the mineral layer around the cocoon of wild silk moths to be removed, leaving only variability in color as a barrier to creating a commercial silk industry based on wild silks in the parts of the world where wild silk moths thrive, such as in Africa and South America. Silk use in fabric was first developed in ancient China. The earliest evidence for silk
3496-510: The domesticated varieties in colour and texture and are therefore less uniform; second, cocoons gathered in the wild have usually had the pupa emerge from them before being discovered so the silk thread that makes up the cocoon has been torn into shorter lengths; and third, many wild cocoons are covered in a mineral layer that prevents attempts to reel from them long strands of silk. Thus, the only way to obtain silk suitable for spinning into textiles in areas where commercial silks are not cultivated
3572-739: The early center of the silk industry in America, when the Cheney Brothers became the first in the United States to properly raise silkworms on an industrial scale; today the Cheney Brothers Historic District showcases their former mills. With the mulberry tree craze of that decade, other smaller producers began raising silkworms. This economy particularly gained traction in the vicinity of Northampton, Massachusetts and its neighboring Williamsburg , where
3648-411: The emperors of China for their own use and gifts to others, but spread gradually through Chinese culture and trade both geographically and socially, and then to many regions of Asia . Because of its texture and lustre, silk rapidly became a popular luxury fabric in the many areas accessible to Chinese merchants. Silk was in great demand, and became a staple of pre- industrial international trade . Silk
3724-435: The fibers and the matrix. Hydrophobic polymer matrices offer insufficient adhesion for hydrophilic fibers. Nanocomposites are desirable for their mechanical properties. When fillers in a composite are at the nanometer length scale, the surface to volume ratio of the filler material is high, which influences the bulk properties of the composite more compared to traditional composites. The properties of these nanosized elements
3800-474: The food industry. Chitin has also been used several of medical applications. It has been incorporated as a bone filling material for tissue regeneration, a drug carrier and excipient , and as an antitumor agent. Insertion of foreign materials into the body often triggers an immune response, which can have a variety of positive or negative outcomes depending on the bodies response to the material. Implanting something made from naturally synthesized proteins, such as
3876-499: The golden silk, and Eri are produced by silkworms that are native only to Assam. They have been reared since ancient times similar to other East and South-East Asian countries. Silk is produced year-round in Thailand by two types of silkworms, the cultured Bombycidae and wild Saturniidae. Most production is after the rice harvest in the southern and northeastern parts of the country. Women traditionally weave silk on hand looms and pass
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#17327661005783952-567: The great Mediterranean mercantile cities. Silk was produced in and exported from the province of Granada , Spain, especially the Alpujarras region, until the Moriscos , whose industry it was, were expelled from Granada in 1571. Since the 15th century, silk production in France has been centered around the city of Lyon where many mechanic tools for mass production were first introduced in
4028-426: The hierarchical structure of many biological materials. These fibrils can form randomly oriented networks that provide the mechanical strength of the organic layer in different biological materials. Chitin provides protection and structural support to many living organisms. It makes up the cell walls of fungi and yeast, the shells of mollusks, the exoskeletons of insects and arthropods . In shells and exoskeletons,
4104-439: The humidity was too high, then it would cause the plants to create mold and bacteria. Humidity would also increase the amount of pests around the plants. Hydrated, biopolymers generally have enhanced ductility and toughness. Water plays the role of a plasticizer , a small molecule easing passage of polymer chains and in doing so increasing ductility and toughness. When using natural fibers in applications outside of their native use,
4180-555: The largest silk exporter in the world. This increase in exports was mostly due to the economic reforms during the Meiji period and the decline of the Qing dynasty in China, which led to rapid industrialization of Japan whilst the Chinese industries stagnated. During World War II , embargoes against Japan had led to adoption of synthetic materials such as nylon , which led to the decline of
4256-624: The larvae of insects undergoing complete metamorphosis , but some insects, such as webspinners and raspy crickets , produce silk throughout their lives. Silk production also occurs in hymenoptera ( bees , wasps , and ants ), silverfish , caddisflies , mayflies , thrips , leafhoppers , beetles , lacewings , fleas , flies , and midges . Other types of arthropods produce silk, most notably various arachnids , such as spiders . The word silk comes from Old English : sioloc , from Latin : sericum and Ancient Greek : σηρικός , romanized : sērikós , "silken", ultimately from
4332-460: The latter part of the 1st millennium BC, though China maintained its virtual monopoly over silk production for another thousand years. Several kinds of wild silk, produced by caterpillars other than the mulberry silkworm, have been known and spun in China , South Asia , and Europe since ancient times. However, the scale of production was always far smaller than for cultivated silks. There are several reasons for this: first, they differ from
4408-465: The lustrous quality of silk fabric. Aristotle wrote of Coa vestis , a wild silk textile from Kos . Sea silk from certain large sea shells was also valued. The Roman Empire knew of and traded in silk, and Chinese silk was the most highly priced luxury good imported by them. During the reign of emperor Tiberius , sumptuary laws were passed that forbade men from wearing silk garments, but these proved ineffectual. The Historia Augusta mentions that
4484-487: The nickname "Silk City" as another major center of production in the United States. World War II interrupted the silk trade from Asia, and silk prices increased dramatically. U.S. industry began to look for substitutes, which led to the use of synthetics such as nylon . Synthetic silks have also been made from lyocell , a type of cellulose fiber, and are often difficult to distinguish from real silk (see spider silk for more on synthetic silks). In Terengganu , which
4560-421: The nineteenth and early twentieth centuries, Japanese exports competed directly with Chinese in the international market in such low value-added, labor-intensive products as raw silk. Between 1850 and 1930, raw silk ranked as the leading export for both countries, accounting for 20%–40% of Japan's total exports and 20%–30% of China's. Between the 1890s and the 1930s, Japanese silk exports quadrupled, making Japan
4636-508: The original level of hydration must be taken into account. For example when hydrated, the Young's Modulus of collagen decreases from 3.26 to 0.6 GPa and becomes both more ductile and tougher. Additionally the density of collagen decreases from 1.34 to 1.18 g/cm . Of industrial value are four animal fibers: wool, silk, camel hair, and angora as well as four plant fibers: cotton, flax, hemp, and jute. Dominant in terms of scale of production and use
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#17327661005784712-402: The potential to be used in the silk sector enabling wet reeling of Wild Silk moth cocoons by removing the mineral layer present in these cocoons . This technique is not like degumming where the gum of the fibroin fibres is removed what would lead to a tangled cocoon. With "demineralizing" the gum and structure of the cocoon is kept intact enabling the cocoons to be wet reeled. This could allow
4788-585: The present day, sometimes spinning wild silk. King James I introduced silk-growing to the British colonies in America around 1619, ostensibly to discourage tobacco planting. The Shakers in Kentucky adopted the practice. The history of industrial silk in the United States is largely tied to several smaller urban centers in the Northeast region. Beginning in the 1830s, Manchester, Connecticut emerged as
4864-437: The reasoning behind the prohibition lies in avoiding clothing for men that can be considered feminine or extravagant. There are disputes regarding the amount of silk a fabric can consist of (e.g., whether a small decorative silk piece on a cotton caftan is permissible or not) for it to be lawful for men to wear, but the dominant opinion of most Muslim scholars is that the wearing of silk by men is forbidden. Modern attire has raised
4940-464: The region: mulberry, endi, and tassar. Bengali silk was a major item of international trade for centuries. It was known as Ganges silk in medieval Europe. Bengal was the leading exporter of silk between the 16th and 19th centuries. The 7th century CE murals of Afrasiyab in Samarkand , Sogdiana , show a Chinese Embassy carrying silk and a string of silkworm cocoons to the local Sogdian ruler. In
5016-743: The silkworms on mulberry leaves. Once the worms start pupating in their cocoons, these are dissolved in boiling water in order for individual long fibres to be extracted and fed into the spinning reel. To produce 1 kg of silk, 104 kg of mulberry leaves must be eaten by 3000 silkworms. It takes about 5000 silkworms to make a pure silk kimono . The major silk producers are China (54%) and India (14%). Other statistics: Production in Int $ 1000 have been calculated based on 1999–2001 international prices Source: Food And Agricultural Organization of United Nations: Economic And Social Department: The Statistical Division The environmental impact of silk production
5092-400: The skill on to their daughters, as weaving is considered to be a sign of maturity and eligibility for marriage. Thai silk textiles often use complicated patterns in various colours and styles. Most regions of Thailand have their own typical silks. A single thread filament is too thin to use on its own so women combine many threads to produce a thicker, usable fiber. They do this by hand-reeling
5168-455: The stiffness increases with strain rate, also known as strain hardening . Spider silk has hard and elastic regions that together contribute to its strain rate sensitivity, these cause the silk to exhibit strain hardening as well. Properties of natural fibers are also dependent on the moisture content in the fiber. The presence of water plays a crucial role in the mechanical behavior of natural fibers. Plants depend on water to help them grow. If
5244-567: The third-century emperor Elagabalus was the first Roman to wear garments of pure silk, whereas it had been customary to wear fabrics of silk/cotton or silk/linen blends. Despite the popularity of silk, the secret of silk-making only reached Europe around AD 550, via the Byzantine Empire . Contemporary accounts state that monks working for the emperor Justinian I smuggled silkworm eggs to Constantinople from China inside hollow canes. All top-quality looms and weavers were located inside
5320-435: The threads onto a wooden spindle to produce a uniform strand of raw silk. The process takes around 40 hours to produce a half kilogram of silk. Many local operations use a reeling machine for this task, but some silk threads are still hand-reeled. The difference is that hand-reeled threads produce three grades of silk: two fine grades that are ideal for lightweight fabrics, and a thick grade for heavier material. The silk fabric
5396-724: The time of the Indus Valley civilisation (now in Pakistan and India) dating between 2450 BC and 2000 BC. Shelagh Vainker, a silk expert at the Ashmolean Museum in Oxford, who sees evidence for silk production in China "significantly earlier" than 2500–2000 BC, suggests, "people of the Indus civilization either harvested silkworm cocoons or traded with people who did, and that they knew a considerable amount about silk." India
5472-412: The triangular prism -like structure of the silk fibre, which allows silk cloth to refract incoming light at different angles , thus producing different colors. Silk is produced by several insects; but, generally, only the silk of moth caterpillars has been used for textile manufacturing. There has been some research into other types of silk, which differ at the molecular level. Silk is mainly produced by
5548-683: Was also used as a surface for writing, especially during the Warring States period (475–221 BCE). The fabric was light, it survived the damp climate of the Yangtze region, absorbed ink well, and provided a white background for the text. In July 2007, archaeologists discovered intricately woven and dyed silk textiles in a tomb in Jiangxi province, dated to the Eastern Zhou dynasty roughly 2,500 years ago. Although historians have suspected
5624-828: Was built in Congleton . These three towns remained the centre of the English silk throwing industry until silk throwing was replaced by silk waste spinning . British enterprise also established silk filature in Cyprus in 1928. In England in the mid-20th century, raw silk was produced at Lullingstone Castle in Kent. Silkworms were raised and reeled under the direction of Zoe Lady Hart Dyke , later moving to Ayot St Lawrence in Hertfordshire in 1956. During World War II , supplies of silk for UK parachute manufacture were secured from
5700-467: Was by tedious and labor-intensive carding . Some natural silk structures have been used without being unwound or spun. Spider webs were used as a wound dressing in ancient Greece and Rome, and as a base for painting from the 16th century. Caterpillar nests were pasted together to make a fabric in the Aztec Empire . Commercial silks originate from reared silkworm pupae, which are bred to produce
5776-618: Was sold in a large market fair in the port of Reggio Calabria , to Spanish, Venetian, Genovese, and Dutch merchants. Catanzaro became the lace capital of the world with a large silkworm breeding facility that produced all the laces and linens used in the Vatican. The city was world-famous for its fine fabrication of silks, velvets, damasks, and brocades. Another notable center was the Italian city-state of Lucca which largely financed itself through silk-production and silk-trading, beginning in
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