Patent ID: 7344665

Claim:
A method of translating liquid material through a coating die comprising: providing a coating die having at least one applicator slot in fluid communication with a die cavity, wherein the die cavity exhibits a volume; disposing an expansible chamber device within the die cavity, wherein the expansible chamber device exhibits an initial volume less than the volume of the die cavity; controlling the pressure of an incompressible fluid within the expansible chamber device to vary the volume of the expansible chamber device by increasing the pressure of the incompressible fluid within the expansible chamber device, thereby increasing the volume of the expansible chamber device from the initial volume to an expanded volume less than the volume of the die cavity, and thereafter decreasing the pressure of the incompressible fluid within the expansible chamber device, thereby decreasing the volume of the expansible chamber device from the expanded volume; and delivering liquid material from the applicator slot at a variable rate influenced by the volume of the expansible chamber device.