Isotropic adhesive film and a flexible metal-clad laminate

Dimensional change of the flexible metal-clad laminate, only the film flow direction (MD direction) and the cross-film direction (TD direction) has been important, as the miniaturization of wiring advances, not only MD · TD direction MD dimensional change of the flexible metal-clad laminate is small is desired also the direction facing to the left and right 45 degrees. An adhesive film provided with an adhesive layer containing a thermoplastic polyimide on at least one surface of the polyimide film, wherein the orientation degree of the adhesive film is 1.3 or less, the adhesive film, solving the above problems It can be.