Radiation sensitive compositions of quaternary ammonium salt and carboxylic acid sensitizer

Claim 1

A radiation sensitive composition comprising (i) a quaternary ammonium salt of the type which will accept at least one electron on exposure to radiation to form a substance capable of causing metal to be deposited onto said substance from an electroless plating solution in contact with said substance and comprising a salt of said metal and a reducing agent, said quaternary ammonium salt having the general formula ##STR5## wherein R 1 to R 10 are hydrogen or halogen atoms or organic substituents; R 11 and R 12 , if present, are each halogen atoms or organic substituents or together represent a divalent organic substituent; Z is zero or an integer; X - is an anion; m=1 or 2; and at least one of the nitrogen atoms is quaternary; provided that R 11 and R 12 are not each --CH 3 groups or are not together a --CH 2 CH 2 -- group when each of R 1 to R 10 is a hydrogen atom and Z is zero, and (ii) a chemical sensitiser for improving the speed of photoreduction of the quaternary ammonium salt, said sensitiser having the general formula ##STR6## wherein R 21 is substituted or unsubstituted aryl group, an arylalkenyl group, or an arylalkyl group; R 22 is a substituted or unsubstituted aryl group, an alkyl group, an arylalkyl group, an arylalkenyl group, a carboxylic acid group, a carboxylic acid salt group, or a hydrogen atom; or R 21 and R 22 together represent a bivalent species; and X represents a carboxylic acid group or a carboxylic acid salt group.