Silk waste includes all kinds of raw silk

Silk

Silk is a natural protein fiber, some forms of which can be woven into textiles. The best-known type of silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity...

 which may be unwindable, and therefore unsuited to the throwing process

Silk throwing

Silk throwing is the industrial process where silk that has been reeled into skeins, is cleaned, receives a twist and is wound onto bobbins. The yarn is now twisted together with threads, in a process known as doubling. Colloquially silk throwing can be used to refer to the whole process: reeling,...

. Before the introduction of machinery applicable to the spinning of silk waste, the refuse from cocoon reeling, and also from silk winding, which is now used in producing spun silk fabrics, was nearly all destroyed as being useless, with the exception of that which could be hand-combed and spun by means of the distaff

Distaff

As a noun, a distaff is a tool used in spinning. It is designed to hold the unspun fibers, keeping them untangled and thus easing the spinning process. It is most commonly used to hold flax, and sometimes wool, but can be used for any type of fiber. Fiber is wrapped around the distaff, and tied in...

 and spinning wheel

Spinning wheel

A spinning wheel is a device for spinning thread or yarn from natural or synthetic fibers. Spinning wheels appeared in Asia, probably in the 11th century, and very gradually replaced hand spinning with spindle and distaff...

, a method which is still practised by some of the peasantry in India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 and other countries in Asia

Asia

Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

.

Sources

The supply of waste silk is drawn from the following sources:

• The silkworm, when commencing to spin, emits a dull, lustreless and uneven thread with which it suspends itself to the twigs and leaves of the tree upon which it has been feeding, or to the straws provided for it by attendants in the worm-rearing establishments: this first thread is unreelable, and, moreover, is often mixed with straw, leaves and twigs.
• The outside layers of the true cocoon are too coarse and uneven for reeling; and as the worm completes its task of spinning, the thread becomes finer and weaker, so both the extreme outside and inside layers are put aside as waste.
• Pierced cocoons, that is, those from which the moth of the silkworm has emerged-and damaged cocoons.
• During the process of reeling from the cocoon the silk often breaks; and both in finding a true and reelable thread, and in joining the ends, there is unavoidable waste.
• Raw silk skein
  Skein
  Skein may refer to:* A flock of geese or ducks in V formation flight* A wound ball of yarn with a center pull strand, see hank* TV Series, used part of Variety's slanguage.* Skein dubh, a Scottish knife* Skein module, a mathematical concept...
  
  s are often re-reeled; and in this process part has to be discarded: this being known to the trade as gum-waste. The same term — gum-waste — is applied to " waste " made in the various processes of silk throwing; but manufacturers using threads known technically as organzines and trams call the surplus "manufacturer's waste."

Processing

A silk "throwster" receives the silk in skein form, the thread of which consists of a number of silk fibres wound together to make a certain diameter or size, the separate fibre having actually been spun by the worm. The silk-waste spinner receives the silk in quite a different form: merely the raw material, packed in bales of various sizes and weights, the contents being a much-tangled mass of all lengths of fibre mixed with much foreign matter, such as ends of straws, twigs, leaves, worms and chrysalis. It is the spinner's business to straighten out these fibres, with the aid of machinery, and then to so join them that they become a thread, which is known as spun silk.

There are two distinct kinds of spun silk: one called schappe and the other spun silk or discharged spun silk. All silk produced by the worm is composed of two substances: fibroin

Fibroin

Fibroin is a type of protein created by Bombyx mori in the production of silk. Silk emitted by the silkworm consists of two main proteins, sericin and fibroin, fibroin being the structural center of the silk, and sericin being the sticky material surrounding it.The fibroin protein consists of...

, the true thread, and sericin

Sericin

Sericin is a type of protein created by Bombyx mori in the production of silk. Silk emitted by the silkworm consists of two main proteins, sericin and fibroin; fibroin being the structural center of the silk, and sericin being the sticky material surrounding it....

, which is a hard, gummy coating of the fibroin. Before the silk can be manipulated by machinery to any advantage, the gum coating must be removed, really dissolved and washed away - and according to the method used in achieving this operation the result is either a schappe or a discharged yarn. The former, schapping, is the French, Italian and Swiss method, from which the silk when finished is neither so bright nor so good in colour as the discharged silk; but it is very clean and level, and for some purposes essential, as, for instance, in velvet

Velvet

Velvet is a type of woven tufted fabric in which the cut threads are evenly distributed,with a short dense pile, giving it a distinctive feel.The word 'velvety' is used as an adjective to mean -"smooth like velvet".-Composition:...

manufacture.

External links

• Essay on silk waste