By Carol Namono
Silks are produced by several other insects, but only the silk of moth caterpillars has been used for textile manufacture. Silk moths lays eggs on specially prepared paper. The eggs hatch and the caterpillar (silkworms) are fed fresh mulberry leaves.
Hatched eggs turning into silkworms feeding on small chopped mulberry leaves
After about 35 days and 4 molting, the caterpillars are 10,000 times heavier than when hatched and are ready to begin spinning a cocoon.
Silkworms feeding on mulberry leaves ready to spin
A spinning frame is placed on the tray of caterpillars, and each caterpillar begins spinning a cocoon by moving its head. Two glands produce liquid silk and force through openings in the head called spinnerets.
silkworms spinning cocoon
Liquid silk is coated in sericin, a water –soluble protective gum, and solidifies on contact with the air. Within 2-3 days, the caterpillar spins about 1mile of filament and is completely encased in a cocoon. The silk farmers then kill most caterpillars by heat (100 0c), leaving some to metamorphose into moths to breed the next generation of caterpillars.
Samples of the moth emerging breeding eggs
Compiled by Carol Namono P.R.O TRIDI
