Magnetic recording medium having a low molecular weight azo dye including an aryl group

A dual layer magnetic recording medium comprising a non-magnetic substrate having a front side and a back side, a back coat formed on the back side, a lower support layer formed over the front side, and a magnetic recording upper layer formed over said lower layer, said magnetic recording upper layer comprising a magnetic metal particle powder dispersed in a binder;

• wherein said lower layer comprises a granular alpha iron oxide compound dispersed in a binder, and as a surface treatment agent, at least one low molecular weight azo dye having the following general formula:
• —Ar—N═N—Ar—
• wherein Ar represents an aryl group, each of which independently comprises at least one pendant group selected from an electron donor, and an electron acceptor, wherein at least one of said pendant groups is an electron acceptor selected from the group consisting of —COOH, —NO2 wherein said electron donor is selected from the group consisting of —OH and —NH2 and wherein said surface treatment agent is acidic chrome orange.