Method and apparatus for coating a substrate

Claim 1

A method of coating a liquid coating composition onto a web substrate from a coating hopper having a downwardly inclined slide, which method comprises the steps of: feeding the liquid coating composition in the form of a layer upon an upper portion of the inclined slide surface such that the liquid flows as a layer by gravity downwardly on the inclined slide surface toward the substrate; altering the direction of flow of the layer at a lower lip portion of the slide surface to a direction closer to horizontal than the direction of the upper portion of the slide surface so that the liquid composition flows more horizontally as it approaches the substrate; flowing the liquid composition from the lower Lip of the slide surface across a generally horizontal gap to the substrate; and moving the substrate in a generally upward direction across and in contact with the coating composition so that the surface of the substrate is coated with the coating composition.

Claim 2

A method of coating a liquid coating composition onto a web substrate from a coating hopper having a downwardly inclined slide, which method comprises the steps of: feeding the liquid coating composition in the form of a layer upon an upper portion of the inclined slide surface such that the liquid flows as a layer by gravity downwardly on the inclined slide surface toward the substrate; altering the direction of flow of the layer at a lower lip portion of the slide surface to a direction closer to horizontal than the direction of the upper portion of the slide surface so that the liquid composition flows more horizontally as it approaches the substrate; flowing the liquid composition from the lower Lip of the slide surface across a generally horizontal gap to the substrate; and moving the substrate in a generally upward direction across and in contact with the coating composition so that the surface of the substrate is coated with the coating composition.

Claim 9

A METHOD OF SIMULTANEOUSLY COATING A PLURALITY OF DISTINCT SUPERPOSED LAYERS OF LIQUID COATING COMPOSITIONS ONTO A WEB SUBSTRATE FROM A COATING HOPPER OF THE TYPE HAVING A DOWNWARDLY INCLINED SLIDE SURFACE, WHICH METHOD COMPRISES THE STEPS OF: SIMULTANEOUSLY FEEDING EACH LIQUID COATING COMPOSITION IN THE FORM OF A LAYER AND IN SUPERPOSED RELATION TO THE OTHER COMPOSITION LAYERS ONTO THE UPPER PORTION OF THE SLIDE SURFACE INCLINED DOWNWARDLY AT A FIRST PREDETERMINED ANGLE WITH RESPECT TO HORIZONTAL SUCH THAT THE LIQUID COATING COMPOSITION LAYERS FLOW DOWN THE SURFACE BY GRAVITY; ALTERING THE DIRECTION OF FLOW OF THE LAYERS AT A LOWER PORTION OF THE SLIDE SURFACE TO A SECOND PREDETERMINED ANGLE OF INCLINATION LESS THAN SAID FIRST ANGLE OF INCLINATION SO THAT THE LIQUID COMPOSITION LAYERS FLOW MORE HORIZONTALLY; FLOWING THE LIQUID LAYERS FROM THE LOWER PORTION OF THE SLIDE SURFACE ACROSS A GENERALLY HORIZONTAL GAP TO A SUBSTRATE TO BE COATED; AND MOVING THE SUBSTRATE IN A GENERALLY UPWARD DIRECTION ACROSS AND IN CONTACT WITH THE LIQUID COMPOSITION LAYERS SO THAT THE SURFACE OF THE SUBSTRATE ENGAGES THE LOWERMOST LAYER AND SIMULTANEOUSKY PICKS UP ALL OF SAID COMPOSITIONS IN DISTRICT SUPERPOSED LAYERS.

Claim 10

A METHOD OF SIMULTANEOUSLY COATING A PLURALITY OF DISTINCT SUPERPOSED LAYERS OF LIQUID COATING COMPOSITIONS ONTO A WEB SUBSTRATE FROM A COATING HOPPER OF THE TYPE HAVING A DOWNWARDLY INCLINED SLIDE SURFACE, WHICH METHOD COMPRISES THE STEPS OF: SIMULTANEOUSLY FEEDING EACH LIQUID COATING COMPOSITION IN THE FORM OF A LAYER AND IN SUPERPOSED RELATION TO THE OTHER COMPOSITION LAYERS ONTO THE UPPER PORTION OF THE SLIDE SURFACE INCLINED DOWNWARDLY AT A FIRST PREDETERMINED ANGLE WITH RESPECT TO HORIZONTAL SUCH THAT THE LIQUID COATING COMPOSITION LAYERS FLOW DOWN THE SURFACE BY GRAVITY; ALTERING THE DIRECTION OF FLOW OF THE LAYERS AT A LOWER PORTION OF THE SLIDE SURFACE TO A SECOND PREDETERMINED ANGLE OF INCLINATION LESS THAN SAID FIRST ANGLE OF INCLINATION SO THAT THE LIQUID COMPOSITION LAYERS FLOW MORE HORIZONTALLY; FLOWING THE LIQUID LAYERS FROM THE LOWER PORTION OF THE SLIDE SURFACE ACROSS A GENERALLY HORIZONTAL GAP TO A SUBSTRATE TO BE COATED; AND MOVING THE SUBSTRATE IN A GENERALLY UPWARD DIRECTION ACROSS AND IN CONTACT WITH THE LIQUID COMPOSITION LAYERS SO THAT THE SURFACE OF THE SUBSTRATE ENGAGES THE LOWERMOST LAYER AND SIMULTANEOUSKY PICKS UP ALL OF SAID COMPOSITIONS IN DISTRICT SUPERPOSED LAYERS.