Aluminum-coating metal composite material and process for producing same

摘要

An aluminum-containing metal composite material useful for heat exchangers having a satisfactory hydrophilic property, water-resistance and resistance to swelling with water and an enhanced durability is produced by coating an aluminum-containing metal substrate with an undercoat chemical conversion layer and then with an uppercoat resinous layer formed from a cross-linking reaction product of a polymeric compound (a) having a reactive amide, hydroxyl or carboxyl group with a cross-linking agent (b), in the presence of a water-soluble polymeric compound (c) having a sulfonic or sulfonate group, and in the cross-linking reaction product, the cross-linked molecules of the polymeric compound (a) form water-insoluble, three-dimensional network structures, and the molecules of the polymeric compound (c) are held in the network structures and thereby exhibit substantially no eluting property in water.