Types of Silk Fibres

In the world of commerce, there exist four distinct types of natural silk. Among them, mulberry silk reigns supreme, accounting for as much as 90 percent of global production. As a result, when people refer to "silk" in a general sense, they are typically referring to the silk produced by the mulberry silkworm. The remaining three commercially important varieties are classified as non-mulberry silks: Eri silk, Tasar silk, and Muga silk. Additionally, there exist various other types of non-mulberry silk, predominantly found in the wilds of Africa and Asia. These include Anaphe silk, Fagara silk, Coan silk, Mussel silk, and Spider silk.

Mulberry Silk

Mulberry silk is the most commonly used silk fibre in the textile industry. It is produced by the Bombyx mori silkworm, which feeds on the leaves of mulberry trees. This silk is known for its lustrous appearance, durability, and softness. It has a fine and uniform texture, making it ideal for high-end fashion garments, such as dresses, blouses, and scarves.

Mulberry silk has excellent tensile strength, elasticity, and moisture absorption properties. It is also highly resistant to wrinkles and creases, making it an ideal fabric for travel wear. Mulberry silk is available in various colours, including white, cream, and ivory. It is mainly produced in China, Japan, and India.

Tussar Silk

The genus Antheraea comprises the Tussar silkworms, which are all classified as wild silkworms. A variety of Tussar silkworms exist, such as the Chinese Tussar silkworm, Antheraea pernyi Guerin, which is the largest non-mulberry silk producer globally. The Indian Tussar silkworm, Antheraea mylittle Dury, follows closely in significance. Additionally, the Japanese tussar silkworm, Antheraea yamamai Querin, is indigenous to Japan and yields green silk thread. The Chinese and Japanese Tussar worms feed on oak leaves and related species, while the Indian Tussar worms subsist on Terminalia leaves and other minor host plants. These worms are either uni- or bivoltine, and, like the mulberry silkworm cocoons, their cocoons can be unraveled into raw silk.

It is mainly produced in India, China, and Japan.

Eri Silk

Eri silk is also known as Endi or Errandi silk. It is produced by the Samia ricini silkworm, which feeds on castor leaves. This silk fibre is known for its rich texture and warmth, making it ideal for winter wear. It has a slightly rough texture, similar to cotton, and is commonly used to make shawls, jackets, and other warm clothing.

Eri silk has excellent insulation properties, making it ideal for cold climates. It is also highly breathable, making it comfortable to wear in warmer weather. This silk is available in a range of colours, including white, beige, and brown. Eri silk is mainly produced in India, China, and Thailand.

Muga Silk

Muga silk is a rare and expensive silk fibre that is produced by the Antheraea assamensis silkworm. This silk is known for its natural golden colour, lustrous appearance, and high durability. Muga silk has a unique texture and is commonly used to make traditional Assamese garments, such as mekhela chador and sarees.

Muga silk has excellent tensile strength and is highly resistant to wrinkles and creases. It also has a natural sheen that gives it a luxurious look and feel. Muga silk is mainly produced in Assam, India.

Anaphe silk

Silk fibres originating from silkworms belonging to the Anaphe genus are produced in central and southern Africa. These silkworm species include A. moloneyi Druce, A. panda Boisduval, A. reticulate Walker, A. ambrizia Butler, A. carteri Walsingham, A. venata Butler, and A. infracta Walsingham. These worms spin their cocoons communally, each cocoon being enclosed by a delicate silk layer. These cocoons are collected from the forest by tribal people, who extract the fluff and spin it into a raw silk that is soft and has a moderate sheen. The silk obtained from A. infracta is referred to locally as "book", and that from A. moleneyi as "Trisnian-tsamia" and "koko" (Tt). Anaphe silk is more elastic and stronger than mulberry silk and is often used in velvet and plush textiles.

Fagara silk

The production of Fagara silk involves obtaining cocoons from the giant silk moth Attacus atlas L. and several related species or races present in the Indo-Australian biogeographic region, China, and Sudan. The cocoons spun by these moths are light-brown and measure approximately 6 cm in length, with peduncles of varying lengths ranging from 2 to 10 cm.

Coan silk

Pachypasa atus D., a type of larvae found in the Mediterranean biogeographic region (southern Italy, Greece, Romania, Turkey, etc.), primarily feed on trees like pine, ash cypress, juniper, and oak. These larvae spin white cocoons that measure around 8.9 cm x 7.6 cm. In the past, this silk was popularly used for producing crimson-dyed clothing worn by Roman dignitaries. However, commercial production of this silk ceased long ago due to its limited output and the emergence of superior silk varieties.

Mussel silk

While the non-mulberry silks discussed earlier are derived from insects, mussel silk is obtained from a bivalve mollusk called Pinna squamosa. These mussels are found in shallow waters along the Italian and Dalmatian shores of the Adriatic Sea. The mussel secretes a robust brown filament, also known as byssus, to anchor itself to a rock or other surface. The byssus is combed and spun into a silk popularly known as "fish wool." The production of this silk is mostly limited to Taranto, Italy.

Spider silk

Spider silk, which is another non-insect variety, is known for its softness and fineness, as well as its remarkable strength and elasticity. Commercial production of this silk is derived from certain species found in Madagascar, such as Nephila madagascarensis, Miranda aurentia, and Epeira. The spinning tubes or spinnerets are located in the fourth and fifth abdominal segments of these spiders. About a dozen individuals are confined to a frame by their abdominal part, from which the accumulated fiber is reeled out four or five times a month. Due to the high cost of production, spider silk is not commonly used in the textile industry. However, its durability and resistance to extreme temperatures and humidity make it essential for crosshairs in optical instruments.

In conclusion, silk is a versatile and luxurious fibre that has been used in textiles for centuries. Each type of silk fibre has its own unique properties and characteristics, making it suitable for different types of garments and home furnishings. By understanding the physical and chemical properties of each type of silk fibre, designers and manufacturers can create high-quality products that meet the needs and preferences of their customers.

Image Source: https://inserco.org/en/types_of_silk

Key Words

1. Mulberry silk

2. Tussar silk

3. Eri silk

4. Natural protein fibre

5. Luxurious feel

6. Shimmering appearance

7. Fine texture

8. Softness

9. Luster

10. Strong and durable

11. Natural golden colour

12. Textured appearance

13. Coarse fibre

14. Sericin

15. Fibroin

16. Sustainable

17. Eco-friendly

18. Samia ricini silkworm

19. Bombyx mori silkworm

20. Wild silk.