What is Raw Silk?
Raw Thai silk is a filament silk from which the gum (one of the components of silk) has not yet been removed. Pure Thai silk has had the gum removed.
Characteristics of Raw Thai Silk
Raw Thai silk is produced by a coarse spinning process; it is less even and slightly knobbed. Raw Thai silk is quite a gummy, sticky substance, so before separating the filaments the cocoons must be softened by immersion in hot water to loosen the gum. Raw silk is typically a short fiber silk recycled from spinning silk.
In the production of mulberry silk only a certain middle section of the cocoon can be unreeled for spinning Thai silk. The waste silk is the raw Thai silk and it has a smooth feel with some bumps and a low luster.
Weaving Raw Thai Silk
Raw Thai silk taken directly from the filature is too fine to be woven. Before it is woven into fabric, it goes through a series of operations which conditions for the loom. They do this by hand-reeling the threads onto a wooden spindle to produce a uniform strand of raw silk.
Raw Thai silk is typically a short fiber silk recycled from spinning silk and has a strong odor due to impurities in the yarn.
The raw yarn’s natural coloring is light beige to bright yellow. The more refined the silk and the smaller the yarn, the more it resembles the look and feel that we know as silky.
Slight imperfections of the weave in the fabric are characteristic of raw Thai silk. The imperfections make raw Thai silk stand out from machine made fabrics.
Appearance of Raw Thai Silk
A raw Thai silk fabric may fool you into thinking that it is cotton or synthetic. The fabric has irregular surface with rough and nubbly appearance. The nubbly texture of the silk comes from the use of very short fibers (called “silk noil”) to weave the fabric.
The luster quality or dullness of the fabric depends upon the filler yarn. Noil is made from the short fibers left after combing and carding, so it does not shine like other Thai silk fabrics. The fabric is stiff and dull and the sericin can attract dirt and odors.
Village laborers use a whisk broom or brush and push the cocoons up and down in the water until some loose end of fiber becomes attached to the broom. A single fiber is very small, and for reeling purposes usually three or four are combined. These are passed through a smooth ring as one fiber and then onto a reel frame which is usually run by foot power, but sometimes by mechanical power in modern reeling plants, or by filatures as they are called.
Silk fiber in its raw state is for its size the strongest textile fiber in existence.
Thai Silk Worm Production
In Thailand, rearing silk worms for production of raw Thai silk is a supplement to the normal rice farming operations and is usually performed by village women.
Matching Dye Colors- Almost Impossible
It takes a great deal of skill to be able to match the color samples when dyeing the yarn, because the weather and time of year can greatly influence how the yarn dyes. In fact, perfect color matching may even be impossible – but this is what helps make Thai silk fabric unique. The raw Thai silk skeins are sorted according to their color, size, length or quantity and washed in warm water with soap or oil for softening the sericin.
The length of the fibers is also a gauge of quality and raw Thai silk has short fiber lengths. Raw Thai silk is one of the least expensive silks and is commonly dyed in pastel colors for use in scarves, soft blouses and linings.
Preparing Raw Thai Silk
Raw Thai silk is washed in soapy water to bring up its gloss and then the warp and weft threads are dyed. Thai weavers separate the completed cocoons from the mulberry bush and soak them in a vat of boiling water to separate the silk thread from the caterpillar inside the cocoon. The average cocoon produces about three hundred yards in a single thread.
A single thread filament is too thin to use on its own so Thai women combine many threads to produce a thicker, usable fiber. 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 raw Thai silk is dyed with natural and artificial dyes.
The raw yarn’s natural colouring ranges from light beige to bright yellow. The raw yarn is not bleached to maintain its strength. The more refined the silk and the smaller the yarn, the more it resembles the look and feel that we know as silky. The raw Thai silk is often expertly naturally dyed by hand, and spun into a fine yarn for weaving.
The production of raw Thai silk is a lengthy process, from the birth of the silk worm to the retrieval of the silk from the cocoon. It is an exceptional and labor-intensive process to obtain the exquisite golden-beige fiber these silkworms produce.