Multiple layer coating method

DETAILED DESCRIPTION The system of the present invention coats a plurality of simultaneously applied layered coating fluids onto a substrate.
The substrate moves along a path through a coating station, and a plurality of layers of coating fluids of different compositions are flowed in face-to-face contact with each other to form a composite layer.
The composite layer flows as a high velocity jet at a speed that is sufficiently high to form a continuous flowing fluid bridge to the substrate surface across the coating width regardless of the direction or the force of gravity.
The flowing composite layer jet impinges the substrate to deposit the coating fluids on the substrate.
The composite jet fluid bridge has a length greater than the wet caliper of coating fluid applied.
The system also can include depositing the composite layer onto a transfer surface, such as a roll or belt, before contacting the substrate.
Also, the system can include an interceptor which interrupts the coating process by blocking the flow before it contacts the web without stopping the substrate or ceasing the other steps.
The fluid bridge may be accelerated by at least one of gravitational, magnetic, or electrostatic forces.
However, this is not essential, and the coating can be performed in a low gravity environment.
In various embodiments, it is possible to have at least one coating fluid that does not wet the substrate, or is not miscible with an adjacent coating fluid, or has a surface tension differing from an adjacent coating fluid, or is in turbulent flow, or is miscible with an adjacent coating fluid.