| abstract |
ABSTRACT A porous coating of bonded metal particles, particularly for coating the metal boiling surfaces of heat exchangers, comprising an aqueous acid coating composition having aluminum particles, an inorganic binder comprising phosphate ions and chromate or molybdate ions, and synthetic acrylate or methacrylate resin, serving as fugitive material removed by solvent or heat curing to create in the coating a system of interconnecting pores open to the surface of the coating and to the substrate. |