Disclosed are curable epoxy compositions comprising imidazolium monocarboxylate salts as curing catalysts and method for curing same. The imidazolium monocarboxylate salt is suitable for use as latent catalysts that effect curing upon heating to a curing temperature threshold. The curable compositions prepared therefrom are used to prepare coated substrates, and to produce conformally sealed printed wiring boards. Of particular utility are curable compositions comprising 2-ethyl-4-methyl imidazolium monocarboxylate salts.