Enzyme Deinking of Black and mite Letterpress &e

,Current deinking processes use large amounts of expensive, potentially environmentally damaging chemicals. A process based on enzymes, which are themselves not hazardous and which preclude the need for alkaline deinking chemicals, was investigated. It was found that cellulases and hemicellulases could effectively deink letterpress-printed old newsprint. Optical and strength properties of the enzymedeinked pulps were superior to control deinked pulps.