Film coater method and apparatus
AssigneeStora Enso North America Corp.
InventorsWayne A. Damrau, John F. Bergin
Life of this patent
Estimating the term…
Abstract
An improved film coater which utilizes one or more coater or applicators to transfer coating to the outer surfaces of at least one more rolls, which in turn transfers the coating from the roll surface to one or more sides of the web for coating paper is disclosed. The coater or applicator includes a smoothing doctor on the web and downstream of the one or more rolls, and may also utilize humidity from one of steam showers or a humidity enclosure to assist smoothing. The web may run in any direction, but preferably runs upwardly from the roll toward the doctor to reduce “film split” droplets effect. The present invention also reduces the fiber rise and arrange peel pattern on the coated web, resulting in a smooth uniform coated paper.
Claims50
A process of coating a paper web with a film coater having one or more applicators, a pair of rolls for coating the paper web, the one or more applicators applying coating to at least the surface of one roll of the pair of rolls, the process comprising the steps of forming a nip with the pair of rolls, applying coating to the rolls with the one or more applicators, running a web through the nip in an upward direction, transferring coating from the roll surface to a side of the web at the nip, separating the web from the roll and creating film split droplets or misting, causing said film split droplets or mist to fall back onto the roll surface, locating one or more doctors above the nip for leveling coating on the web, and leveling and smoothing the coating on the web with the one or more doctors for minimizing any residual film split pattern and fiber rise, whereby the web can be coated and the film split droplets falling back onto the rolls.
An apparatus for coating a web, with a film coater having one or more coating applicators, and one or more rolls for coating a paper web, the one or more applicators applying coating to the roll surface of said one or more rolls, a nip formed with said one or more rolls, a web adapted to run through said nip with said one or more rolls transferring coating from said roll surface to the adjacent side of the web at the nip, and one or more leveling and smoothing devices located after said nip for leveling the coating on the web and smoothing the coating, whereby the web can be coated with the film split droplets and misting falling back onto the rolls.
A process of coating a paper web with a film coater having one or more applicators, a pair of rolls for coating the paper web, the one or more applicators applying coating to at least the surface of one roll of the pair of rolls, the process comprising the steps of:
- forming a nip with the pair of rolls, applying coating to the rolls with the one or more applicators, running a web through the nip, transferring coating from the roll surface to an adjacent side of the web at the nip, separating the web from the roll, and creating film split droplets or misting, causing said film split droplets or mist to fall back locating one or more doctors after the nip for leveling coating on the web, and leveling and smoothing the coating on the web with the one or more doctors for minimizing any residual film split pattern and fiber rise, whereby the web can be coated.
A process of coating a paper web with a film coater having one or more applicators, a pair of rolls for coating the paper web, the one or more applicators applying coating to at least the surface of one roll of the pair of rolls, the process comprising the steps of forming a nip with the pair of rolls, applying coating to at least one of the rolls with the one or more applicators, running a web through the nip, transferring coating from the roll surface to an adjacent side of the web at the nip, separating the web from the roll and creating film split droplets or misting, causing said film split droplets or mist to fall back, locating one or more doctors after the nip for leveling coating on the web, and leveling and smoothing the coating on the web with the one or more doctors for minimizing any residual film split pattern and fiber rise enclosing said doctors in a humid enclosure whereby the web can be coated.
An apparatus for coating a web, with a film coater having one or more coating applicators, and one or more rolls for coating a paper web, the one or more applicators applying coating to the roll surface of said one or more rolls, a nip formed with said one or more rolls, a web adapted to run through said nip with said one or more rolls transferring coating from said roll surface to the adjacent side of the web at the nip, one or more leveling and smoothing devices located after said nip for leveling the coating on the web and smoothing the coating, and an enclosure for enclosing said web adjacent said one or more leveling and smoothing devices in a humid atmosphere, whereby the web can be coated.
Dependencies are inferred from the claim text.