Moisture application system for a paper web
AssigneeWestvaco Corporation
InventorDonald G. Bauer
Life of this patent
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Abstract
The moisture application system of the present invention comprises in combination a first means for applying liquid to a paper web and a second means in contact with the web for scraping off excess liquid and spreading the liquid uniformly across the paper web. The moisture application system of the present invention is particularly useful when combined with a machine calender for finishing a paper web.
Claims14
An apparatus for finishing a web of paper to provide enhanced smoothness with minimal loss of caliper comprising:
- a calender device including at least two calender rolls arranged in nipped relation through which a paper web is passed, and at least one moisture application system associated with said calender adjacent to the nip between said calender rolls, said moisture application system consisting essentially of a moisture application means which is an array of tubes, spray nozzles, jets or slots, said moisture application means being structured and arranged to apply a film of liquid directly onto the surface of the paper web prior to the web entering the nip when the calender rolls are rotated, and a first metering device arranged to cooperate with the paper web to scrape off excess liquid and control the thickness and uniformity of the liquid film applied to the paper web before the web enters the calender nip;
- wherein said metering device comprises a metering element that is selected from the group consisting of a blade and a rod.
A method of finishing a web of paper in a calender device to provide enhanced smoothness with minimal loss of caliper comprising:
- (a) applying a film of liquid directly to the surface of a paper web using a moisture application system consisting essentially of a moisture application means which is an array of tubes, spray nozzles, jets or slots, said moisture application means applying the film of liquid to the paper web before it is passed through one or more nips formed by calender rolls in a calender device, wherein said nips are formed by at least two calender rolls arranged in nipped relation;
- and
- (b) metering excess liquid from the surface of the web before it enters the calender nip by contacting the film of liquid on the surface of the web with a metering device to form a thin film of liquid sufficient to cover the entire surface of the web;
- wherein the metering device comprises a metering element that is selected from the group consisting of a blade and a rod.
Dependencies are inferred from the claim text.