| 摘要 |
<p>709,359. Photographic diazotype copies. CHEMISCHE FABRIEK L. VAN DER GRINTEN N.V. Sept. 12, 1952 [Sept. 19, 1951; Sept. 19, 1951], No. 23022/52. Class 98(2) The process of Specification 708,151 in which diapositives and kinematograph films with continuous tone gradation as well as ordinary diazo copies are made by selectively exposing a "diazo film layer" containing a p-aminobenzene diazo compound which yields an active photochemical decomposition product, as described in that Specification, rendering the copy alkaline and then developing with an aqueous solution of a coupling compound; is modified by (1) employing, additionally, in the " diazo film layer " a diazo compound which yields a less active or inactive photochemical decomposition product, and (2) adding part of the coupler during the intermediate step of rendering the copy alkaline. For (1) Example 1 specifies the zinc chloride double salt of p-diazo-o-chloro-diethylaniline or the corresponding m-chloro compound as additional diazo compound, and for (2) Example 2 specifies phloroglueinol as coupler, part of which is added during the intermediate step. Softer gradation results from both of these modifications.</p> |
