| abstract |
Substances (I) capable of being converted into higher-molecular weight materials under the influence of a cationic catalyst, such as 1,2-epoxides, aminoplasts, vinyl monomers or prepolymers, or phenoplasts, are so converted by exposure to actinic irradiation or by heating in the presence of an aryloxysulfoxonium salt of formula <IMAGE> II where either R6 and R7 separately denote lower alkyl (optionally substituted by halogen and interrupted in the chain by -O- or -SO2-), or an aryl or aryloxy group, or R6 and R7 together denote a divalent group forming with the S atom a heterocyclic radical; R8 denotes an aryl group; M denotes an atom of a metal or metalloid; X denotes a halogen atom; and n is 4, 5, or 6, for instance, p-chlorophenoxy-p-tolyl-p-phenoxysulfoxonium hexafluorophosphate and 1-phenoxy-1-oxidotetrahydrothiophenium tetrafluorborate. When I is an epoxide resin or a resol resin, it may be photopolymerized by means of II and subsequently crosslinked with a latent heat-curing agent. |