A technique in which layers of flat colour are printed using a RISO duplicator, a machine based on mimeograph technology developed by Japanese company RISO. A paper stencil is made from a black-and-white design and wrapped tightly around a cylindrical drum of coloured ink. This is rotated and has paper fed past it, leaving an impression of the stencil on the paper. One colour is printed per stencil: a print can be made up of several stencilled layers of different transparent inks.