Consolidated Papers, Inc.

Sherwood G Holt

George H Rasmussen

An improved method and apparatus for applying a film of coating material on a moving web of paper carried through an application zone, utilize a reservoir of liquid coating material established under pressure between liquid seals at forward and rearward ends of the zone, and a doctor blade loaded against the web rearwardly of the rearward liquid seal. The reservoir is formed by forward and rearward relatively movable, sealed members, the upper edges of which define gaps with the paper web and doctor blade, respectively, in which gaps the liquid seals are formed. Coating material is flowed under pressure and in excess into the application zone to enable a pressurized area of coating material to be developed therein against the web and immediately upstream of the doctor blade, with the excess of coating material overflowing from the zone through the gaps to form the liquid seals. The provision of two overflow routes for excess coating material aids in skipless application of coating on the web.

Paper coating method

Applicators for applying a film of coating material on a moving web of paper carried through an application zone include a chamber which receives coating material under pressure and directs the material through a narrow outlet orifice into the application zone, and a doctor blade which extends from a trailing side of the zone in contact with the web. The upper edge of a front wall of the chamber is closely spaced from the web to form, in conjunction with the pressurized coating material flowing from the orifice, a liquid seal at a forward end of the application zone, and seals are established at opposite side ends of the zone to allow development of a positive liquid pressure in the zone. In the various embodiments, rotating rolls located in the chamber, in the orifice, in the space between the upper edge of the front wall and the web and in both the space and the orifice serve to meter, homogenize and control the pressure of coating material in the application zone.

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Biron, WI, United States of America

Sherwood G Holt