Resin coated metal substrates

摘要

An article comprising a metal substrate in the form of a pipe or a container, said substrate being coated with a hardened epoxy resin composition formed from (A) a solid epoxy resin based on epichlorohydrin and a component selected from the group consisting of (a) 4,4'-diphenylolpropane, (b) 4,4'-diphenylolmethane and (c) a combination of (a) and (b), (B) from 1 to 12% by weight based on the epoxy resin of at least one hardener for said epoxy resin selected from the group consisting of (d) compounds of formula <IMAGE> (I) wherein R is hydrogen or an alkyl group of 1 to 6 carbon atoms or an aromatic hydrocarbon residue with 6 to 10 carbon atoms, (e) compounds of formula <IMAGE> (II) wherein R is hydrogen or an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon residue with 6 to 10 carbon atoms and (f) an adduct of any one of compounds (d) and (e) to an epoxy resin with an epoxy equivalent weight of from 50 to 2000, (C) a flow agent, (D) a thixotropic agent and a process of coating such metal substrate by means of heating said substrate to a temperature above the melting temperature of the epoxy resin component of an epoxy resin coating composition and sufficient to cure the said epoxy resin and powder-coating the said epoxy resin composition onto the hot surface of the substrate to provide a substantially uniform coating thereon by immediate hardening without any further processing step by means of the heat capacity of the hot substrate.