Positive-working radiation-sensitive copying composition and method of using to form relief images

A process for the production of relief images which comprises imagewise exposing a positive-working recording layer, of a radiation-sensitive recording material comprising a support and a recording layer, to actinic radiation to an extent such that the solubility of the layer in an aqueous developer solution is increased, and removing the irradiated portions of the layer by means of an aqueous developer solution,

• said recording layer comprising
• (a) from about 0.1 to 10 percent by weight, based on the weight of the solids of the composition of a compound which forms an acid under the influence of actinic radiation, and
• (b) an organic polymeric compound which contains recurrent units corresponding to the general formula I:
• ##STR12## wherein n--is an integer between 1 and 40,
• R.sub.1 and R.sub.4 are H, alkyl or aryl groups,
• R.sub.3 and R.sub.6 are alkylene oxy groups with at least two carbon atoms, and
• R.sub.2 and R.sub.5 are alkyl or aryl groups, two of the groups R.sub.1, R.sub.2 and R.sub.3 and two of the groups R.sub.4, R.sub.5, and R.sub.6 may be combined to form a substituted or unsubstituted ring,
• R.sub.3 and R.sub.6 --are alkylene groups with at least two carbon atoms, and
• R.sub.2 and R.sub.5 --are alkoxy groups which form a substituted or unsubstituted ring with R.sub.3 or R.sub.6, and wherein
• R.sub.3 --may be combined with R.sub.4 and R.sub.1 may be combined with R.sub.6 of the neighboring unit to form substituted or unsubstituted rings.