A method for applying a multi-layer coating includes passing a substrate through a nip defined by two rolls to apply a first thickness of a first liquid coating material, applying a second liquid coating material on the first liquid coating material having the first thickness as applied by passing through the nip, and controlling a thickness of the applied second liquid coating material.

A device (4) for applying a viscous liquid, in particular an MFC dispersion, onto a moving substrate (52) comprises an inlet (72, 73a-73f) for the viscous liquid, a casting chamber (61a, 61b), a lower portion of which being open to the substrate (52), and a metering portion (69, 661), for limiting a thickness of a wet film that is formed on the substrate downstream of the device. The device further comprises a shear section (42) arranged inside the casting chamber (61a, 61b). The shear section (42) comprises a fluidization rod (68), arranged in the casting chamber (61a, 61b), for providing shearing of the viscous liquid inside the casting chamber (61a, 61b).

A device (4) for applying a viscous liquid, in particular an MFC dispersion, onto a moving substrate (52) comprises an inlet (72, 73a-73f) for the viscous liquid, a casting chamber (61a, 61b), a lower portion of which being open to the substrate (52), and a metering portion (69, 661), for limiting a thickness of a wet film that is formed on the substrate downstream of the device. The device further comprises a shear section (42) arranged inside the casting chamber (61a, 61b). The shear section (42) comprises a fluidization rod (68), arranged in the casting chamber (61a, 61b), for providing shearing of the viscous liquid inside the casting chamber (61a, 61b).