Abstract: A gauge for measuring the size of a nip between a pair of rolls is characterized by a cylindrical carrier within which a platform is mounted for pivotal movement about the carrier axis. A transducer is carried on the platform, and a quasi U-shaped rod or probe is pivotally connected at one end with the platform, extends along a medial portion thereof outwardly of the carrier and presses against the transducer at an opposite end. The probe is pivotally urged in a direction outwardly of the carrier, and in use of the gauge the medial portion of the probe is moved into the nip between the rolls and against the rolls and the carrier into contact with the rolls, whereby the transducer provides a readout in accordance with the radii of the rolls at the point of contact by the probe.

Abstract: 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.

Abstract: To measure the opacity of sheet material, such as paper, a beam of light is directed against the material and the intensity of any light passing through the material is sensed and converted to a visual readout. A plurality of opacity measurements are made at different areas on the sheet material and, when a selected number of measurements have been made, a readout of the average value of the measurements is generated. The particular technique enables a large number of opacity measurements to be quickly and conveniently made and averaged, and is considerably less complicated and time consuming than opacity measurements which are conventionally made as a function of contrast ratios.

Abstract: An applicator for applying a film of coating material on a web of moving paper carried through an application zone and having a coater blade for doctoring the material on the web as it exits the zone, includes an internal leveling blade within the application zone. The leveling blade divides the application zone into leading and lagging coating material application chambers, and levels the material applied on the web in the leading chamber as the web moves into the lagging chamber. The leveling blade produces a pressure and shear point of coating material to paper so as to cause coating penetration and filling of voids and valleys in the paper, and the coater blade then levels and meters the film of fresh coating applied on the web in the lagging chamber to complete the process.

Abstract: An edge dam or edge seal assembly for an applicator for applying a coating liquid to a moving web of paper carried on a backing roll, the applicator being of the type having a chamber for receiving coating liquid and an opening therein for directing the liquid onto the web, the opening being formed between a front wall of the chamber and a doctor blade exending from the rear of the opening to against the web, is characterized by an expandable seal element sealed with the front wall and doctor blade in an end space therebetween and extending toward and closely adjacent to but spaced from the web. The seal element is of a flexible material and accommodates the introduction of pneumatic or hydraulic fluid under pressure therein for expanding the same to a size which fills the end space and seals the same, and which extends a sealing surface of the element very closely adjacent to the web or backing roll.

Abstract: An improved edge or end dam assembly for an applicator for applying a coating liquid to a web of moving paper carried on a backing roll, the applicator being of the type having a chamber for receiving the coating liquid and an opening therein for directing the liquid onto the web, the opening being formed between a front wall of the chamber and a doctor blade extending from the rear of the opening to against the web, is characterized by a seal element sealed with the front wall and doctor blade in an end space therebetween and extending toward and closely adjacent but spaced from the web. The face of the seal element adjacent the paper web has a plurality of grooves extending generally parallel to the direction of movement of the web, so that coating material which seeps past the seal element and beyond the edge dam assembly enters the grooves and is moved by the web toward the doctor blade for deposit on the web.

Abstract: A method and apparatus are disclosed for use with a paper coater located on a backing roll of, for example, a papermaking machine. In the method, apparatus in the form of a hinged bridge is used to collect excess coating liquid from a remote doctor blade or a first coater having such blade and supply the same to a second coater. The bridge may be mounted to the doctor blade or the first coater so that it can be placed in a bridging position accommodating various angles of the doctor blade, or in a second stored position wherein it will not interfere with the operation of either coater or the doctor blade.

Abstract: A coated paper having high bulk, excellent gloss and low surface mottle is prepared by first coating the paper with an aqueous composition containing pigment and a thermoplastic binder. The paper is then initially dried at a temperature of up to about 20.degree. F. above the minimum film-forming temperature of the binder until the moisture content of the sheet reaches from about 8 to about 18% by weight. The drying temperature is then increased to further dry the paper, and the dry coated paper is then calendered.

Abstract: A contrasting color is imparted to the decorative surface of a decorative laminate by inserting a pigment coated release sheet between the molding caul and the decorative surface during the molding operation, with the pigment facing the decorative surface. Upon application of heat and pressure during the formation of the laminate, color is transferred from the release sheet to the decorative surface. A suitable technique is also used to emboss or impart surface texture to the decorative surface during molding. Thereafter, the textured surface is subjected to rubbing or brushing to remove more color from the embossed or raised areas than the debossed areas, thereby highlighting or imparting a shaded effect to the textured surface.

Abstract: A method and apparatus for applying a film of liquid pigmented coating material to a moving web of paper at, and between, a low limit of two pounds per ream per side and a high limit of fifteen pounds per ream per side. The method and apparatus utilize a reservoir of liquid coating material established between a forward liquid coating material seal and a rearward pneumatically loaded and clamped doctor blade spaced a small distance of a few inches or less from the liquid seal. The reservoir is pressurized in the range of 7 to 150 inches of water so that the coating material is applied under pressure to the moving web and then almost instantaneously wiped by the doctor blade. The reservoir is formed by two relatively movable, sealed members which may be opened for easy cleaning, and may have one or more internal coating material distribution headers at its end opposite the web to uniformly distribute the coating material.

Abstract: A method for making an application or dip roll for applying a coating, such as an aqueous clay and starch solution, from a trough, onto a moving web on a papermaking or coating machine. The roll comprises a roll cylinder having a hard, outer surface which is not subject to attack by the coating to be used. A plurality of minute indentations are formed in the outer surface of the roll to enhance the transfer of coating from the trough to the roll. Preferably, the roll is first provided with a smooth surface finish. Then the plurality of indentations are formed by shot blasting the outer surface of the roll with hard shot. If a shot of a material subject to attack by the coating is used, the roll may be subsequently blasted with another material, not subject to such attack, so as to remove any fragments of the first shot that might have become embedded in the roll.