Mercerised cotton
Cotton yarn or cloth treated with a strong alkali under tension, to make it stronger, shinier and better at taking dye.
Also: mercerized cotton, mercerisation
In mercerisation, cotton is soaked in a strong solution of caustic soda while it is held under tension, then rinsed. The fibre swells and becomes rounder, so it reflects more light and looks silkier, and it takes dye more deeply and evenly. It also gains some strength. The process is named for John Mercer, an English chemist who worked on it in the 1840s. Many handloom cotton sarees are made of mercerised yarn, which gives them a slight sheen compared with plain cotton.