The Story Of Silk

Silk is an expensive, smooth and strong fabric. A silk rope is actually stronger than an equally thick metal wire! This precious and smooth silk is obtained from the life of a silkworm. And today, we will be discussing the history of silk and how it became the greatest textile today.

The cultivation of silkworm to produce silk is called sericulture. Let us understand the process of sericulture first. The tiny eggs of the silk moth are incubated till they hatch into larva. At this point, the larva gets about a quarter of an inch long. Then, the larva are placed in a net layer and fed huge amount of chopped mulberry leaves. During this time, they shed their skin four-five times. The larva which feed on the mulberry leaves produce the finest silks in the world. A fun fact to know is a silk-moth larva eats up to 50,000 times its weight, in mulberry leaves. The larva continuously eats up to 6 weeks and grows to a maximum size of 3 inches.

Then it changes its color to brown. After 6 weeks, silkworm gets about 10,000 times heaver than its initial weight! Also, did you know that a single silk worm pupa can produce up to 15 meters of fiber per minute! The pupa then attaches itself to a tree to spin a silk cocoon over a 3-8 days period. This period is called pupating. In the next 4 days, it rotates its body in a figure 8 movement for around 300,000 times! Another fun fact up your sleeve, a pupa can produce 1 kilometer of silk.

The cocoon is then treated with hot air, steam or boiling water. The silk is then unbound from the cocoon and the silk thus gets obtained. But the sad part is, the amount of usable silk from cocoon is very small because it takes 10kg of cocoon to produce 1kg of silk. Such difference must be taken into account considering the fact that the lives of silkworms are also getting sacrificed during this process. This is the process how silk is generally obtained. But you may have a question here that how did we know silkworm produced silk at the first place? Let us see the history behind this in detail now.

The Chinese had invented or rather discovered the silk. They had kept the idea of silk secret for about 1000 years. The first evidence of silk was found at the sites of Yang Shao Culture in Xia County, Shanxi. The silk cocoon was cut up in half which was found around 4000-3000 B.C.E. This specie which came out of cocoons was known as the "Bombyx Mori". Long ago in the 27th century B.C.E, a silkworm's cocoon fell into the tea cup of the empress Leizu. And the silk discovery was thus done. Empress Leizu was since then known as the Goddess of Silk in Chinese Mythology.

So that was the history of silk. Now coming back to the traditional method of sericulture, we can see that these silk industries had a great downfall. The reasons weren't shocking either. It was responsible for the exploitation of natural resources, overuse of silk worms and cocoons, high prices. The process involved was also exposed to get infections which eventually led to a disease in silkworms in the 1860's. Scientists had to do something new.

Count Hilaire de Chardonnet and Louis Pasteur were trying to find the solution of this disease in silkworms in the 1860's. Then in 1885, Chardonnet patented the first successful process of making Rayon which is also known as artificial silk, which is prepared from cellulose and chemical treatment of rags and wood pulp. DuPont, a synthetic company, marketed this Rayon material and it got famous throughout the world. DuPont also produced:

• Nylon
• Kapton
• Teflon
• Lycra
• Corfam etc.

Count Hilaire de Chardonnet is since then also known as the father of Rayon.

Fashion, home fabric and carpet industries have benefited a lot from Rayon. But Rayon was soon replaced by Nylon and Teflon because of its elasticity and lack of wrinkling and many other advantages over Rayon. Tyre cords were also replaced with nylon and polyester tyre cords.

Still, silk and rayon continue to flourish through the textile industry and are known for their valuable texture and appearance. Silk clothing is popular in many countries and has even became a cultural symbol for many communities and societies. All through the history, several silk routes have been discovered which were considered as the most valuable trade routes for trading. Thus we see, silk has played a major role in both social and scientific world of living.

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