|1.||Also called: photogelatine process a method of lithographic printing from a flat surface of hardened gelatine: used mainly for fine-detail reproduction in monochrome or colour|
|2.||a print made using this process|
|[C19: from Greek kolla glue + |
photomechanical printing process that gives accurate reproduction because no halftone screen is employed to break the images into dots. In the process, a plate (aluminum, glass, cellophane, etc.) is coated with a light-sensitive gelatin solution and exposed to light through a photographic negative. The gelatin is hardened in exposed areas and is then soaked in glycerin, which is absorbed most in the non-hardened areas. When exposed to high humidity, these areas absorb moisture and repel the greasy ink. The hardened areas accept the ink, and the plate can be used to print a few thousand copies of the positive image
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