UV Curable compositions and substrates treated therewith

Curable or polymerizable compositions comprising by weight

• (A) 15 to 100% of a C.sub.(8-12) .alpha.-olefin oxide,
• (B) 0 to 85% of a polyfunctional epoxy resin,
• (C) 0.1 to 10% based on the sum of the weight (A), (B) and (C) of an aryl onium salt of the formula,
• [Y].sup.+ [MQ.sub.n ].sup.-,
• where Y is a member selected from
• [(R).sub.a (R.sup.1).sub.b I] and
• [(R).sub.c (R.sup.2).sub.d (R.sup.3).sub.e S],
• where R is a monovalent aromatic organic radical, R.sup.1 is a divalent aromatic organic radical, R.sup.2 is a monovalent organic aliphatic radical selected from alkyl, cyano alkyl and substituted alkyl, R.sup.3 is a polyvalent organic radical forming a heterocyclic or fused ring structure, M is a metal or metalloid, Q is a halogen radical, a is a whole number equal to 0 or 2, b is a whole number equal to 0 or 1, and the sum of a+b is equal to 1 or 2, c is a whole number equal to 0 to 3 inclusive, d is a whole number equal to 0 to 2 inclusive, e is a whole number equal to 0 or 1, and the sum of c, d and e is equal to 1 to 3 inclusive, and n is an integer equal to 4-6 inclusive.