This invention relates to an improvement in a photochemical process for the preparation of printing plates wherein a printing plate comprising a photosensitive composition coated on a support is exposed to a pattern of laser light, the intensity of which is modulated in accordance with an input source of information and said printing plate is subsequently developed by removal from said support of that portion of the photosensitive coating composition which is not exposed to said pattern of laser light, the improvement comprising utilizing a pattern of laser light generated by a laser at a wavelength greater than about 450 nm, and utilizing as a photosensitive composition a negative-working condensate of a para-aminobenzene diazonium compound, said compound being present in a quality of at least 25% of the total coating weight.
本发明涉及一种用于制备印刷版的光
化学过程的改进方法,其中包括在支撑物上涂覆一种光敏组合物的印刷版,将该印刷版暴露于激光光图案中,其强度根据信息源进行调制,随后通过从所述支撑物中去除未暴露于所述激光光图案的光敏涂层组成部分来开发该印刷版,所述改进方法包括利用由波长大于约450nm的激光产生的激光光图案,并利用作为光敏组合物的负作用的对
氨基苯二
酚重氮化合物的凝聚物,其中该化合物的质量至少占总涂层重量的25%。