Although prices were stable, the company had a potential revenue generator in "Tencel", a man-made fibre Courtaulds had spent £100 million and 10 years bringing to market. Like viscose, Tencel is made from cellulose derived from dissolved wood pulp. While rayon production generates large amounts of sulfurous waste, Tencel is made with a "closed loop" chemical process in which the solvent can be filtered and reused. The final product is far stronger than rayon or cotton, which allows a huge variety of different forms and feels – from ultrasoft yet strong denim jeans, to shirts that feel like silk, to scarves that ape the texture of cashmere.