Natural organic materials (wood, horn, skin, etc.) have been used since the dawn of humanity. Textile fabrication from vegetal fibers (linen, cotton, etc.) or from animals (silk, wool, etc.) reached an “industrial” stage from the Middle Ages onwards. The idea of changing raw matter by specific physical or chemical treatment (dyeing fibers, leather tanning, etc.) is practically as ancient as the applications themselves. In the 19th century, however, a new idea emerged: chemically modifying natural substances (fibers, skins, etc.) so as to make them into completely different from the natural forms
