Pressure feed coating application system

A method for use with a coating apparatus for coating a web with a liquid, the web having a width and moving in a first direction, the apparatus comprising an applicator roll having a first axis perpendicular to the first direction and positioned in rolling contact in the first direction with the web, a stiffener having first and second ends and rotatable about a second axis, the second axis parallel with the first axis, the stiffener elongated in the axial direction, the stiffener comprising a first nozzle and a second nozzle, each of the first nozzle and the second nozzle elongated in the axial direction;

• the stiffener movable between first and second positions, the stiffener in said first position juxtaposing the first nozzle with the applicator roll, the stiffener in said second position juxtaposing the second nozzle with the applicator roll;
• each of the first nozzle and the second nozzle comprising a metering surface, a flexible back seat resting against the applicator roll when juxtaposed therewith, and end seals at respective first and second ends of the stiffener, the metering surface and back seal each elongated in the axial direction and parallel with each other and with the end seals defining a reservoir cavity;
• the stiffener further comprising first and second feed pipes corresponding with the first and second nozzles, each feed pipe feeding to the reservoir cavity of the respective nozzle;
• the nozzles less wide in the axial direction than the width of the applicator roll, the arrangement of the back seal and the metering surface such that the applicator roll when rolling encounters first the back seal and afterwards the metering surface;
• the method comprising the steps of:
• placing the stiffener in the first position and resting its back seal against the applicator roll;
• providing the liquid to the reservoir cavity of the first nozzle by either gravity or a low pressure pump;
• moving the web in the first direction;
• rolling the applicator roll in contact with the web;
• applying liquid to the applicator roll via the first nozzle;
• transferring liquid to the web from the applicator roll;
• ceasing provision of the liquid to the reservoir cavity of the first nozzle;
• rotating the stiffener to the second position and resting its back seal against the applicator roll;
• providing the liquid to the reservoir cavity of the second nozzle by either gravity or a low pressure pump;
• applying liquid to the applicator roll via the second nozzle;
• transferring liquid to the web from the applicator roll;
• ceasing provision of the liquid to the reservoir cavity of the second nozzle;
• and
• rotating the stiffener to the first position.

Coating apparatus for coating a moving web with a liquid, the web having a width and moving in a first direction, the apparatus comprising:

• a stiffener having first and second ends and rotatable about a second axis, the second axis parallel with the first axis, the stiffener elongated in the axial direction, the stiffener comprising a first nozzle and a second nozzle, each of the first nozzle and the second nozzle elongated in the axial direction;
• the stiffener movable between first and second stiffener positions, the stiffener in said first stiffener position juxtaposing the first nozzle with the web, the stiffener in said second stiffener position juxtaposing the second nozzle with the web;
• each of the first nozzle and the second nozzle comprising a metering surface, a flexible back seal resting against the web when juxtaposed therewith, and end seals at respective first and second ends of the stiffener, the metering surface and back seal each elongated in the axial direction and parallel with each other and with the end seals defining a reservoir cavity;
• the stiffener further comprising first and second feed pipes corresponding with the first and second nozzles, each feed pipe feeding to the reservoir cavity of the respective nozzle;
• the nozzles less wide in the axial direction than the width of the web, the arrangement of the back seal and the metering surface such that the web when moving encounters first the back seal and afterwards the metering surface;
• the liquid provided to the reservoir cavity, when juxtaposed with the web, from either gravity or a low pressure pump.

A method for use with a coating apparatus for coating a web with a liquid, the web having a width and moving in a first direction, the apparatus comprising a stiffener having first and second ends and rotatable about a second axis, the second axis parallel with the first axis, the stiffener elongated in the axial direction, the stiffener comprising a first nozzle and a second nozzle, each of the first nozzle and the second nozzle elongated in the axial direction;

• the stiffener movable between first and second positions, the stiffener in said first position juxtaposing the first nozzle with the web, the stiffener in said second position juxtaposing the second nozzle with the web;
• each of the first nozzle and the second nozzle comprising a metering surface, a flexible back seal resting against the web when juxtaposed therewith, and end seals at respective first and second ends of the stiffener, the metering surface and back seal each elongated in the axial direction and parallel with each other and with the end seals defining a reservoir cavity;
• the stiffener further comprising first and second feed pipes corresponding with the first and second nozzles, each feed pipe feeding to the reservoir cavity of the respective nozzle;
• the nozzles less wide in the axial direction than the width of the web, the arrangement of the back seal and the metering surface such that the web when moving encounters first the back seal and afterwards the metering surface;
• the method comprising the steps of:
• placing the stiffener in the first position and resting its back seal against the web;
• providing the liquid to the reservoir cavity of the first nozzle by either gravity or a low pressure pump;
• moving the web in the first direction;
• applying liquid to the web via the first nozzle;
• ceasing provision of the liquid to the reservoir cavity of the first nozzle;
• rotating the stiffener to the second position and resting its back seal against the web;
• providing the liquid to the reservoir cavity of the second nozzle by either gravity or a low pressure pump;
• applying liquid to the web via the second nozzle;
• ceasing provision of the liquid to the reservoir cavity of the second nozzle;
• and
• rotating the stiffener to the first position.