FROM MULBERRY LEAF TO SILK FABRIC…
Since millions of years, a tiny bug produces the most robust yarn known on earth. The eggs of this bug sleep for a year and the newborns miraculously develop in a short period, up to 10,000 times their initial weight. They literally “imprison” themselves in a cocoon in order to produce the thread which is used to create the most exquisite fabrics that are considered as “the most beautiful and the most exquisite”.
In the meantime the silkworm itself, becomes a dazzling butterfly by gaining a completely different appearance.
Silk which has been the most preferred fabric for centuries with its softness and brilliance, is made from the cocoons produced by the silkworms. These miraculous creatures, interestingly, feed on mulberry leaves only.
Once the silkworms complete their development, they begin to knit cocoon to become a butterfly. And finally they lock themselves in their own cocoons and fall into sleep. This process starts with a tiny silkworm which evolves into a silk-woven cocoon and finally a butterfly. How does this happen? Now let's examine this miraculous process from the beginning.
The Cocoon Knitting Circuit Begins
Once the silkworm gets out of its egg, it chooses a branch with great meticulousness to use as a hanger and ties itself up with the same yarn. Then the silkworm starts to excrete silk and wraps itself with the silk and starts to build up its cocoon. The cocoon knitting process ends in Multivoltin races within 2-3 days, in uni and bivoltin races in 3-4 days. While pulling out the yarn, the silkworm continuously moves its head as if drawing an “8” and continues the knitting process from one part of the cone to the other part. Without getting dizzy or losing its balance, the silkworm keeps repeating this movement approximately 130000 times within a period of 3-4 days. During this period, the silkworm excretes a yarn of 900-1500 m in length. Although you would expect the silkworm to have stiff muscles or lose its functionality, it keeps its production with great effort. When the silk production ends, instead of dying, the silkworm transforms into a pupa.
How does the silkworm transform from pupa to a butterfly?
On the 4th or 5th day of knitting the cocoon, the silkworm transform into a pupa. After 8-14 days of pupa period, the butterfly comes out. Here again we witness another miracle. A silkworm hides itself behind a cocoon produced by its own secretion and disappears from sight. Although it used to be a creeping creature before hiding itself, it starts flying as a butterfly within two weeks.
Due to the alkaline structure of its saliva, the butterfly penetrates the cocoon and frees itself. To sum up, the butterfly which used to be a silkworm is aware that it is held in a cocoon, it is time to get out and it needs a special liquid to penetrate the cocoon so therefore produces this liquid in its own body.
How is the silk produced?
The knitting procedure of the cocoon is a never ending process for 3-4 days. This tiny creature shows an extraordinary effort by working non-stop for a couple of days. We can understand this better by comparing with human beings. Although a human being shows signs of weakness physically and mentally in lack of sleep, the silkworm in as energetic as ever. The silkworm produces the most robust yarn on earth, in a cycle from egg to silkworm and from silkworm to butterfly.
According to the research; the secret of silk production lies in the secretory glands of silkworms and how the water-solubility of silk proteins is controlled. The entire process is kept under control by the amount of water. The organism sends protein to the silk gland, but controls how much water is left there when doing so. This precise balance play an important role in the durableness of silk.
Silk is the most Durable Known Natural Thread
The robust natural thread that silk bugs produce is also a source of inspiration for scientists. However, scientists have not yet succeeded in producing a durable thread as such. Scientists who have expanded their research in recent years are still trying to reach the secret of such strong yarns produced by the silkworms. Experts; in the field of medicine, claim that it can be used to repair damaged knee ligaments and create artificial bone tissue, and that if the findings are proven correct, artificial silk can be produced in the laboratory for bone tissue as well as producing very strong protective clothing and sporting goods.