| 摘要 |
The invention relates to a recording material having a substrate and a negative-working, radiation-sensitive layer which contains a diazonium salt, at least a first polymeric binder, which is film-forming, and organic coloured pigments, on the surface of which an organic polymeric dispersant has been adsorbed and which are additionally dispersed in a second polymeric binder which does not permanently combine with the pigments chemically or physically. The first and the second polymeric binder may be the same or different. The dispersant generally has groups, in particular primary, secondary or tertiary amino groups or derivatives thereof, which act as anchor groups on the coloured pigment particles. The pigments themselves are preferably phthalocyanine pigments. As a result of the predispersing, aggregation of the pigment particles is effectively prevented so that uniform coloration of the radiation-sensitive layer is achieved. During development of the imagewise exposed recording materials, the coloured pigment particles form virtually no insoluble precipitates. In the prepared printing plates, the printing parts are distinguished from the substrate material through being clearly visible and having high contrast.
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