Silk

Silk is a protein filament fibre produced by certain moths, spiders and other insects.

How is Silk made?

Silk fabric is created mainly by ‘Silkworm Moths’ called Bombyx Mori. These larvae are fed on Mulberry leaves to produce the only natural fibre that is a filament fibre. This means that it can be one long continuous fibre if the conditions are products needed for manufacture are endless. The worm secretes a protein like substance when it enters its pupa stage of life. This protein is called Sericin and it is wrapped around the worm in a cocoon for protection. The most common method of harvesting Silk is to immerse the pupa in worm water and then cold water to soften the gum-like protein. The silk filament can then be refined and processed ready to be wound into skeins and then woven into various silk fabrics.

The practice of rearing silk worms for silk production is known as ‘sericulture’ and has been practised in China for thousands of years, and was a national secret. Nowadays however, silk is still widely cultivated in China, as well as Japan and Italy and many other countries.

Different types of Silk Worm

The most commercial and common type of Silkworm used in textile manufacture is still the Bombyx Mori, however in Thailand they use cultured Bombycidae and wild Saturniidae breeds for their Thai Silk fabric.

Tasar, Muga and Eri silk are other variations of silkworm. These are mainly found in the wild, in remote forests and they produce ‘Wild’ Silk. This is also known as Tussah, eco, or Shantung Silk. This type of silk generally has a less lustrous look and handle as it is created in the conventional way, by the Silkworms chewing their own way out of their cocoon and therefore breaking the otherwise continuous filament.

Main Physical Properties of Silk Fabric

• Fine, Smooth, Lustrous Handle
• Elegant Drape
• Elastic, Fairly crease resistant
• Can be quite clingy and static due to it being a poor conductor of electricity
• One of the strongest natural fibres around
• Durable and Lightweight
• Cool, but also a good insulator so provides warmth when needed
• Not slippery like synthetic fibres
• Absorbs moisture well
• Reflects light giving it a shiny appearance
• Poor resistance to sunlight
• Retains its shape well and is relatively flat
• Is easily dyed
• Recommended as being dry clean only as it will shrink
• Can be used in the medical profession to created surgical sutures and to help people with serve skin allergies due to its non absorbable properties and flat, non itchy thread.
• Can be made waterproof using a polyurethane coating.

Different Types of Silk Fabric

• Silk Chiffon- Silk Chiffon is a fabric made from cultivated Silk; it is extremely thin fabric, semi-transparent fabric woven in a plain weave with a tightly twisted fine yarn. It is often used for scarves and blouses.

• Organza Silk – A very fine fabric made with tightly twisted yarn. It is lightweight, stiff and sheer. It is most commonly used for bridal and eveningwear or even in interior furnishings.

• Habutai, Habotai, China Silk, Pongee– A soft, lightweight durable silk fabric, made in a plain or twill weave. It is one of the cheapest Silk fabrics available and is mainly used in lining. It tears very easily under pressure so it is important not to use it for tight fitting garments.

• Thai Silk – Thai Silk is purely the name given to any Silk manufactured in Thailand by native Thai Silkworms.

• Crepe, Crepe de Chine – Crepe de Chine is made using a plain weave with a twisted two-ply yarn. One of the fibres is twisted clockwise and the other anti-clockwise. This is then woven and a unique ‘pebbly’ appearance is created.

• Taffeta Silk – Taffeta is another plain woven silk fabric made using silk threads. It is characterised by its smooth crisp handle, which can hold its shape better than cotton. It is often used in the manufacture of ladies wear, lingerie and corsetry.

• Satin Silk – Satin Silk is the most common type of silk, and the one we generally think of when we think of silk. The name refers to the fact it is manufactured using the ‘Satin’ weave, giving it a smooth, shiny, lustrous surface. It is used mainly for luxurious garments, underwear and even interior furnishings and bedding. Please note, this shouldn’t be confused with Sateen.

• Charmeuse Silk – This is another fabric that we think of as ‘conventional’ silk. It again is made using a Satin weave giving it the shiny lustrous ‘right’ side of the fabric, but the wrong side of the fabric has a flat crepe look. It is often confused with ‘Satin’ Silk but Charmeuse Silk is more expensive, has a better handle and is more lightweight.

• Jacquard Silks – These fabrics are very handle and are made using a Jacquard weave. This can be created using matte and reflective threads to create a contrasting pattern. This end result is very similar to Brocade fabrics.

• Silk Noil – This is a lower grade Silk fabric made using the shorter fibres that are leftover from the manufacture of other silk fabrics. It is generally weaker and cheaper than other Silk fabrics, without their shine, but it is however stronger and has a better handle than cotton.

• Dupion, Douppioni, Dupioni, Shantung silk – A course uneven fabric made from fibres spun jointly by two silkworms from two joined cocoons, resulting in a yarn of irregular thickness. The fabric is course and has a rough appearance. It is used mainly in upholstery fabrics, but thinner variations can be used in bridal and eveningwear.

As a note to consider, other types of silk exist but under different names. Most commonly a silk made in a certain region is called by that regions name. An example of this is Murshidabad Silk which is produced in the Murshidabad district of West Bengal.

Although filament silk is mainly produced as a pure fibre, it can be blended with other fabrics to create fabrics with two purposes and therefore more end uses. Mixed with Elastane creates a shiny fabric that stretches well.