Latent acid curable compositions

A composition consisting essentially of:

• A. an acid hardenable phenolic resin;
• and
• B. from about 3% to 20% by weight of the resin of an aryl phosphite having the formula ##STR7## wherein each of R and X is phenyl, m-cresyl, or p-cresyl and Y is hydrogen.

A method for preparing a hardened phenolic resin composition at ambient temperature which comprises:

• contacting a phenolic resin which is acid hardenable with an aryl phosphite in an amount sufficient to harden the resin, said phosphite being solvolyzed prior to contact with the resin with from about 1% to 10%, based on the weight of phosphite, with a member selected from the group consisting of water, an alkanol having from 1 to 4 carbon atoms, and an alkylene glycol of 2 to 4 carbon atoms, said phosphite having the formula ##STR9## wherein each of R and X is aryl of 6 to 12 carbon atoms, and Y is a member selected from the group consisting of aryl of 6 to 12 carbon atoms, alkyl of about 1 to 12 carbon atoms, and hydrogen;
• and wherein the phosphite is in contact with a sufficient total water content to hydrolyze the phosphite.

A method for the ambient temperature hardening of a phenolic resin composition which comprises contacting an acid hardenable phenolic resin with an aryl phosphite in an amount sufficient to harden the resin in the presence of a total water content sufficient to hydrolyze the phosphite while increasing the acidity of the composition due to hydrolysis of the phosphite and hardening the composition at a pH of less than 4, said phosphite having the formula

• wherein each of R and X is aryl of 6 to 12 carbon atoms, and Y is hydrogen.

A composition consisting essentially of:

• A. an acid hardenable phenolic resin;
• and
• B. from about 3% to 20% by weight of the resin of an aryl phosphite having the formula ##STR11## wherein each of R and X is phenyl, m-cresyl, or p-cresyl and Y is hydrogen.