| 摘要 |
1,164,839. Planographic printing plate. A. B. SCHAFLER and A. K. LOMBARDO. 22 Nov., 1966 [22 Nov., 1965 (2)], No. 52177/66. Heading B6C. [Also in Division C7] A planographic printing plate comprises a base sheet 10, a sublayer 11 of copper or nickel, a copper composite layer formed of a bright copper layer 12 bonded to a matte copper layer 13, and a smooth, hard chromium layer 14. In between the sublayer 11 and the bright copper layer 12, a layer of chromium can be provided which is bonded to the copper layer 12 by a thin nickel layer, thus providing the plate with amendable characteristics. The chromium layer 14 should be substantially non-porous, but the two copper layers 12, 13 and the sublayer 11 may have a low porosity, any capillary effect being broken by the provision of the number of individual layers Fig. 2. The base material 10 is ferrous steel or aluminium sheet. The plate is prepared by electroplating, the bright copper layer 12 being deposited from a bath containing acid and a brightener, the matte copper layer 13 being deposited from an acid bath containing a double metal salt. |
