In intaglio printing, such as the etching and the steel engraving, the design to be printed is lower than the surface of the plate, which is wiped clean before each impression, leaving the incised design filled with ink, which the paper receives. In gravure intaglio printing, tone is produced by varying the thickness of the ink of the printing surface through depressions of varying depth; minute points constitute the clean surface that keeps the paper from being pressed into the depressions. In photogravure the gravure plate is made by a photographic process. Rotogravure is photogravure adapted for printing by a rotary or cylinder press.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.