| 摘要 |
. During start-up or run-on of a printing machine, a printed image is transferred from a printing cylinder (2, 24, 34) on a control or test cylinder (5, 26,35) which has a surface representative of the surface of a substrate (6, 25, 33) on which printing, later on, is to be effected, for example a white ceramic surface of roughness comparable to that of paper. The image transferred on the control or test cylinder is optically tested while the cylinder rotates over a first partial circumferential range (7, 27, 36), and data derived, either by human observation or by electrooptical sensors (8, 28, 37) to permit readjustment of operating systems of the printing machine in accordance with desired operating parameters, such as register, inking density, ink/damping fluid relationship in offset processes or the like. The printed image is then erased, extinguished or removed, for example by cleaning, by a cleaning apparatus (13, 30, 39) located in a second subsequent range (12, 29, 38) of the circumference of the control or test cylinder. Ink stripped off the control or test cylinder is recycled, and washing fluid ant ink are separated, for separate recycling. When appropriate printing is obtained on the control or test cylinder (5, 26, 35), substrates can then be passed through the printing machine and printing carried out without prior scrap test prints. The method and system are suitable for all printing methods, but are preferably and primarily used in offset printing systems and methods.
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