Solution casting method

A solution casting method is provided. The solution casting method is capable of obtaining a film roll having no black streak extending on the circumference direction in a circumstance of using a welding portion extending in a length direction disposed at the band of the side as a casting support. A ring band of which the central part and the side part are welded in an integrated manner is used as the casting support. The band is transferred along the length direction in a circular manner. The doped is casted in a way of forming a casting film on the central part and the side part. The film 27 stripped from the band and dried is winded to the scroll core 66 to fabricate a film roll. By shifting the forming region 27w on the welding part of the film 27 along a B direction in certain amplitude, the film 27 is winded to the scroll core 66 while the rotation axis 55 is reciprocated in the B direction by using the moving mechanism 61.