A coating apparatus (1) for the continuous manufacturing of steel strips S coated with a varnish for electrical applications comprising a tank (2), a coating roll (3) and an applicator roll (4) wherein: - said tank (2) is able to contain a varnish solution and is configured such that said coating roll (3) is in contact with said varnish solution, - said coating roll (3) is configured to be in contact with said applicator roll (4) and to homogenously transfer, in the steel strip width direction, said varnish onto said applicator roll (4), - said applicator roll (4) is configured to be in contact with said steel strip S, and to homogeneously coat said steel strip in the width of said steel strip and the surface of said applicator roll has a hardness from 40 to 60 shores A.