The invention relates to novel radiation-sensitive compounds which are esters or amides of a 1,2-naphthoquinone-(2)-diazide-4-sulfonic acid of the general formula ##STR1## in which R.sub.1 and R.sub.2 are identical or different and denote hydrogen, an alkyl group, an alkyl ether group or an alkyl thioether group whose carbon chains may be interrupted by ether oxygen atoms, an acylamino group, carboxylic acid ester group, sulfonic acid ester group or sulfonamide group,R.sub.1 and R.sub.2 not being hydrogen at the same time.The compounds are used as radiation-sensitive components in radiation-sensitive mixtures with which corresponding copying materials can be produced. The compounds have an absorption which is directed towards longer wavelengths matching the emission range of commercially available radiation sources. They also make it possible, in a reliable and practical manner, to carry out negativeworking image reversal processes.