2A Silk

Question 1

Where is silk from?

Answer 1

From the cocoon of the bombyx mori/Mulberry silk moth, produced when the caterpillar begins to propate and secrete fibroin from a spinneret - as it hits the air it solids and is coated in sericin (used to wind the cocoon)

Question 2

Properties (silk)

Answer 2

• absorbent/anti-static: can absorb up to 1/3ths of its weight without feeling wet
• cool to wear(wicking)
• strong/resilient: stronger than steel of the same weight/stronger than cool and cotton
• comfortable: fine/soft
• naturally lustrous/smooth: drapes well and has a good handle
• non-conductor of hear: cool in summer/warm in winter
• biodegradable
• prone to damage by sunlight and mildew
• moderate elasticity: most don’t crease easily

Question 3

Structure (silk)

Answer 3

Unique, prism-like structure: reflects light at different angles, giving silk its lustrous appearance

The structure impacts the strength, lustre and ability to absorb moisture

Question 4

Fabrics (silk)

Answer 4

• damask
• chiffon
• taffeta
• organza
• satin
• crepe de chine
• wild silk: coupon, shantung

Question 5

Finishes (silk)

Answer 5

Type of finish used depends on the type of silk/end-use
- stone wash: ultra soft surface
- calendaring
- flame retardant

Question 6

Aftercare (silk)

Answer 6

• can be dry-cleaned
• cool wash but difficult to wash
• no bleach
• iron when damp

Question 7

End-uses (silk)

Answer 7

• accessories: scarves/gloves
• clothing (formal attire): (wedding) dresses/blouses/evening wear/lingerie
• soft furnishings

Question 8

Blends (silk)

Answer 8

Usually pure

Question 9

Testing (silk)

Answer 9

Burning: produces a small flame that slowly extinguishes

Smell: similar to burnt hair

Residue: black cinders

Question 10

Impact of silk production on the environment

Answer 10

The caterpillars are killed in the harvesting process, as the cocoons are harvested before the moth emerges.

By submerging unbroken cocoons in boiling water, this allows filaments to be unwound at continuous lengths

When finishing the silk, the silk must be de-gummed(to remove sericin) and then boiled in soap/detergent/enzymes - chemicals which can leak into waterways and negatively impact the environment

Question 11

Features of silk production

Answer 11

• one cocoon produces between 1000/1500 metres of silk filament
• one metre of silk uses around 3000 cocoons
• 5.5kilos of cocoons reduces only 0.5kilos of raw silk