Silk is a natural protein fibre, which is woven to construct a silk fabric. Silk fabric is one of such fabric which is mainly used as a royal fabric, its embody luxury and elegance. Silk is a protein fiber, similar to wool or to human hair. It is only natural for silks to have some irregularities – sometimes called “slubs”. This is the nature of the 100% silk fabric. The protein fibre of silk is composed mainly of fibroin and produced by certain insect larvae to form cocoons. Silks are produced by several other insects, but generally only the silk of moth caterpillars has been used for textile manufacturing.
A fine lustrous fiber composed mainly of fibroin and produced by certain insect larvae to form cocoons, especially the strong, elastic, fibrous secretion of silkworms used to make thread and fabric. Silk fibers from the Bombyx mori silkworm have a triangular cross section with rounded corners, 5-10 μm wide. Therefore, silk fabric is one of the strong natural fibre.
Silk has a smooth, soft texture that is not slippery, unlike many synthetic fibers.
Silk is one of the strongest natural fibers but its strength changes according to the wetness and dryness of the fibre. Silk fabric 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 a small amount, it remains stretched.But its strength can be weakened if it is exposed to too much sunlight. It may also be attacked by insects, especially if left dirty. Silk is a poor conductor of electricity.
Silk fibre emitted by the silkworm consists of two main proteins, sericin and fibroin. The silk worms are treated to a luxurious life to produce their cocoons. Their environment is kept at controlled temperatures through their life cycles to insure they will live to produce a cocoon.
The high proportion (50%) of glycine, which is a small amino acid, allows tight packing and the fibers are strong and resistant to breaking. The tensile strength is due to the many interceded hydrogen bonds, and when stretched the force is applied to these numerous bonds and they do not break.
Silk is resistant to most mineral acids, except for sulfuric acid, which dissolves it. It is yellowed by perspiration. Chlorine bleach will also destroy silk fabrics. Each silkworm cocoon is made up of a single fiber that is 600 to 900 meters long. Five to eight strands of the filament that are unwound from a silk worm cocoon are used to create silk thread.
Silk’s absorbency makes it comfortable to wear in warm weather and while active. Its low conductivity keeps warm air close to the skin during cold weather. It is often used for clothing such as shirts, tiES, blouses, formal dresses, high fashion clothes, lining, lingerie, pajamas, robes, dress suits etc.
Silk’s attractive lustre and drape makes it suitable for many furnishing applications. It is used for upholstery, wall coverings, window treatments (if blended with another fiber), rugs, bedding and wall hanging.