Silk is a natural filament fiber. This luxury fiber was initially
cultured and woven into fabric by the Chinese as early as the 27th century
BC. However, silk production didn't spread to Japan and Korea until
about 300 AD.
Silk fiber is the result of unwinding the cocoon of the silkworm.
Sericulture, or the cultivation of the silkworm, is carefully monitored
from the egg to the larva, the chrysalis, and lastly the adult moth.
Most of the cocoons are not allowed to progress to the moth stage, but are
soaked in hot water to release the filaments from the sticky "glue" that
holds them together. These filaments are reeled off the cocoons,
and strands of raw silk are made from a number of filaments wound
together. Silk yarn is produced by twisting two or more strands
together. Then silk fabrics are woven from these yarns.
Silk fabrics are comfortable to wear; they are warm in winter and cool in
summer. They resist wrinkling, and they dye and print well.
There are a number of different silk fabric types, from soft and fragile
to heavy and stiff. Silk gazar is crisp and of medium weight,
while silk organza is thin and uniquely sheer. Raw silk, or
noil, has a dull finish; sand-washed silk appears brushed; and shantung
silk is crisp with a sheen and slubs in the woven fabric. Tussah
silk, made from wild silkworms whose filaments are coarse and uneven,
has a rough, nubby appearance. Dupion is a crisp fabric, with
irregular slubs in the yarn. Thai silk is similar to dupion, but
finer and lighter in weight and bulk. Sometimes silk yarns are
even woven into tweed fabrics.
Silk fabrics can shrink, and most require dry cleaning. Some can
be slippery to sew with. Silk fibers can be combined with other
fibers such as cotton or wool. While the silk fiber is produced
mostly in China, India, and Japan, some of the best silk fabric is woven
in France and Italy. Luxury silk fabrics can be quite costly.