Surface treatment agent, method for producing surface treatment film, and aluminum material or aluminum alloy material having surface treatment film

The invention provides a non-chromate surface treatment agent which is capable of forming a surface treatment film between an aluminum material or the like and an upper layer film without using one ormore iron group compounds selected from among oxides of iron, nickel or cobalt, hydroxides of these metals and oxyhydroxides of these metals, the surface treatment film exhibiting excellent adhesionto the aluminum material or the like and to the upper layer film, while providing the aluminum material or the like with excellent corrosion resistance; a method for producing a surface treatment film, which uses the surface treatment agent; and an aluminum material or aluminum alloy material having the surface treatment film. The above-described problem is able to be solved by a surface treatmentagent which contains (A) a water-soluble or water-dispersible organic polymer that has a carbonyl group and/or a hydroxyl group in each unit structure and (B) an organic compound having a phosphonicgroup. 本发明提供种非铬酸盐表面处理剂、使用该表面