Process of smoothing and compressing a material (notably paper ) during production by passing a continuous sheet through a number of pairs of heated rolls.
The rolls in combination are called calenders; they are made of hardened steel or steel covered with fiber. In paper production, they typically exert a pressure of 500 lbs per linear in. (89 kg per cm). Coated papers are calendered to obtain a smooth, glossy finish. Calendering is also widely used in the manufacture of textiles , coated fabrics, and plastic sheeting.