Fijne, ononderbroken proteïnevezel die voornamelijk bestaat uit fibroïnedraden en wordt afgescheiden door zijderupsen.Fibra proteica continua y fina formada fundamentalmente de filamentos de fibroína, secretada por orugas de seda.A fine, lustrous, natural fiber obtained from the catepillar cocoons of silk moths, such as the domesticated Bombyx mori. Silkworm silk is composed of a heavy and light chain of core proteins called fibroins, which are coated by sericin, a collection of sticky, glue-like proteins. Microscopically, raw silk appears as two strands that are held together with sericin protein. According to legend, silk was discovered by Chinese Empress Si-Ling-Shi when a cocoon fell in her tea. China maintained a monopoly on the production of silk fabric for almost 3,000 years.The worms were first cultivated in Japan about 195 CE and in Europe about 555 CE.