Improvements in or relating to resin compositions curable with ultraviolet light.

摘要

Resin compositions comprising 20 to 50% by weight, based on total composition weight, of a first resin which comprises an acrylate-epoxy oligomer having a molecular weight of from 2000 to 5000; from 2 to 10% of a second resin which comprises an acrylate-urethane oligomer; up to 50% of a third resin which comprises a second acrylate-epoxy oligomer, where from 1 to 5% of the epoxy is an epoxy novolac; from 10 to 40% of a liquid acrylate; from 2 to 20% of a liquid diacrylate having an ether linkage; from 5 to 25% of a liquid alkylene diacrylate; and from 1 to 5% of a UV photoinitiator. The compositions also preferably includes from 0.05 to 1% of a flow control agent. The compositions are applied to substrates such as printed wiring boards and cured with ultraviolet light to form a conformal coating on the substrate.