Alcan International Limited

Robert Arthur Innes

Melville D Ball

Gary J Smith

Neil Louis Brockman

Carl A Wollam

David G Hallam

A process and apparatus, including a separate coating head, for coating a strip article with a coating material. The process involves coating a strip article with a film of coating material by passing the strip article through a coating apparatus having at least one floating coating head provided with a coating face facing and extending laterally across a surface of the strip article to be coated. The coating head exudes a coating material and floats on the coating material as it meters the coating to a film of the desired thickness. The coating face of the coating head has a preferred coating profile between its opposite ends, and wherein distortions of the preferred coating profile during coating of said strip article are substantially prevented by modifying heat flux to or from selected parts of the coating head to compensate for distortions caused by differences of temperature within the coating head. The apparatus provides means of modifying heat flux to prevent such distortions of the coating profile. A removable coating head also includes such means of modifying the heat flux.

Process and apparatus for profile control of direct coaters

A coating head, and coating apparatus and methods using the coating head, for applying a solvent free coating material to a strip article advancing longitudinally in a coating line. The head includes a die having a transverse slit through which the coating material is deposited on the strip surface and having a land portion with an extended land surface on the exit side of the slit, the die being supported for movement normal to the strip surface, and one or more air or hydraulic cylinders exerting a load on at least the land portion of the die to urge the land surface toward the strip, wherein the die is constituted of a main body and the land portion, and the land portion is so connected to the main die body as to be capable of flexing relative to the main die body in a direction normal to the strip surface but to resist flexing in the direction of strip advance in the coating line.

Apparatus and method for coating sheet or strip articles

A process of producing an elongated coated strip article having a layer of coating material on each opposite surface of the strip article, in which the ratio of layer thicknesses on opposite sides of the strip article may be set or varied. The process comprises simultaneously applying layers of solidifiable liquid coating materials on the opposite sides of the strip article by advancing the strip article in a direction along a path between opposed coating heads, at least one of which is a floating coating head, having material delivery slots and metering lands for delivery and metering of the liquid coating materials to the opposite surface to form the layers. The ratio of the layer thicknesses may be adjusted when required by varying the path of strip article advance between the floating coating heads to cause changes in angles formed between the strip surfaces and adjacent metering lands on opposite sides of the strip article. The invention also provides apparatus for carrying out the process.

Control of coating thickness in sheet article coaters

A method of applying a multi-layer coating to a surface of an elongated strip article (10) of variable thickness or surface height. The method involves applying at least two layers (12a, 12b,) of different coating materials in the form of solidifiable fluids directly onto the surface (10a, 47, 48) of the elongated metal strip article and reducing the layers to a desired thickness by causing the applied coating materials to encounter at least one coating surface (27) that is movable substantially perpendicularly relative to the strip article and is urged towards the strip article in opposition to hydrodynamic force generated by the coating materials on the at least one coating surface. Differences of thickness or surface height of the strip article are therefore accommodated unduly varying the coating thickness. In the method, one layer (12b) is coated on top of another (12a) in such a way that an outer coating layer is applied on an immediately underlying layer before the immediately underlying layer solidifies. The invention also relates to apparatus for carrying out the method.

Multi-layer coating of elongated strip articles

Coating of wax-like materials onto moving strip articles

A process and apparatus for coating a surface of an elongated strip article, e.g. aluminum sheet, with a layer of solid polymer material. The process involves heating the polymer to produce a melt having a viscosity of at least 1000 centipoise when measured according to ASTM D4440 at 1 radian per second, extruding the melt onto a moving surface of the strip article through an elongated slot in a coating head having an extended surface adjacent to the slot arranged at an angle to the moving surface to form a coating gap converging in the direction of movement, thereby forming a coating on the strip article, and pushing the coating head towards the surface of the strip article as the melt is extruded as the coating onto the surface from the slot to reduce the coating thickness to a desired range by pressing the extended surface of the coating head onto the coating as the coating is formed. The apparatus includes coating heat, provided with a heater to maintain the viscosity of the melt, and load application device for the coating head, as well as means for melting the polymer and supplying the melt under pressure and at the desired temperature to the coating head. The process and apparatus allows strip articles to be coated with thin (1-100 microns) coatings of polymer materials without employing liquids as solvents or the like that cause atmospheric pollution problems.

Coating strip material with protective/decorative layers while avoiding

Apparatus for coating both opposed major surfaces of an elongated strip article with paint, lacquer, lubricant or the like, using two facing coating heads respectively having lands, between which the strip is advanced. Liquid coating material, delivered to the strip surfaces through elongated slits formed in the coating heads immediately upstream of the lands, is dragged out on the moving surfaces as layers metered between the lands and the strip. A load is continuously exerted (by devices such as air cylinders) on at least one of the lands during the coating operation for urging the lands against the applied coating layers.

Apparatus for two-sided coating of elongated strip articles

A process and apparatus for coating a surface of an elongated strip article, e.g. aluminum sheet, with a layer of solid polymer material. The process involves heating the polymer to produce a melt having a viscosity of at least 1000 centipoise when measured according to ASTM D4449 at 1 radian per second, extruding the melt onto a moving surface of the strip article through an elongated slot in a coating head having an extended surface adjacent to the slot arranged at an angle to the moving surface to form a coating gap converging in the direction of movement, thereby forming a coating on the strip article, and pushing the coating head towards the surface of the strip article as the melt is extruded as the coating onto the surface from the slot to reduce the coating thickness to a desired range by pressing the extended surface of the coating head onto the coating as the coating is formed. The apparatus includes coating heat, provided with a heater to maintain the viscosity of the melt, and load application device for the coating head, as well as equipment for melting the polymer and supplying the melt under pressure and at the desired temperature to the coating head. The process and apparatus allows strip articles to be coated with thin (1-100 microns) coatings of polymer materials without employing liquids as solvents or the like that cause atmospheric pollution problems.

Coating strip material with protective decorative layers while avoiding

Apparatus for coating a strip article comprises a coating head having a coating surface and elongated open-sided slot formed in the coating surface communicating with an interior channel for delivery of coating material to said slot for transfer to a strip article to be coated. The slot has a slot extension extending into the coating surface at at least one longitudinal end of the slot for applying coating material to an edge region of the strip article. The slot extension communicates with the interior channel only through a constricted opening that prevents substantial leakage of coating material from the slot extension when the slot extension becomes uncovered by the edge region of the strip article. In this way, the strip article can be coated completely up to its transverse edges, without risk of substantial spillage of coating material if the ends of the coating slot become uncovered by the strip article due to inaccurate tracking or variable strip width.

Method and apparatus for coating strip article up to strip edge

Color change devices which are capable of undergoing a color change on bending. The devices comprise a flexible substrate having a color generating metal (e.g. a valve metal such as Ta or Nb) at at least one surface and an intimately contacting optically thin anodic film covering the color generating metal and generating a visible color by light interference and absorption effects. The thin anodic film is produced by anodizing the color generating metal in the presence of an adhesion-reducing agent (e.g. a fluoride) for weakening the normally tenacious bond between the anodic film and the metal. Devices of this kind capable of being activated by bending, as well as by separation of the constituent layers, are produced by carrying out the anodization step in the presence of a particular concentration of the adhesion reducing agent from a narrow range (e.g. 40-350 ppm of fluoride). The devices can be used as tamper evident labels and the like which show evidence of removal of the labels from articles to which they were originally attached as an indication of tampering.

Color change devices activatable by bending

Color change devices which are capable of undergoing a color change on bending. The devices comprise a flexible substrate having a color generating metal (e.g. a valve metal such as Ta or Nb) at at least one surface and an intimately contacting optically thin anodic film covering the color generating metal and generating a visible color by light interference and absorption effects. The thin anodic film is produced by anodizing the color generating metal in the presence of an adhesion-reducing agent (e.g. a fluoride) for weakening the normally tenacious bond between the anodic film and the metal. Devices of this kind capable of being activated by bending, as well as by separation of the constituent layers, are produced by carrying out the anodization step in the presence of a particular concentration of the adhesion reducing agent from a narrow range (e.g. 40-350 ppm of fluoride). The devices can be used as tamper evident labels and the like which show evidence of removal of the labels from articles to which they are originally attached as an indication of tampering.

Method of making color change devices activatable by bending and product

Apparatus and procedure for applying a paint or like coating to an elongated strip article using a coating head having an open-sided slot to which coating material is supplied under pressure, and a support such as a roll around which the strip is advanced past the head for receiving from the slot a layer of paint metered between the head and the strip, wherein a load is continuously exerted on the head during operation for urging the head against the applied paint layer on the strip so as to maintain a uniform metering gap between the head and the coated strip surface. The load may be exerted by devices such as air cylinders acting on the head and capable of adjustment to vary the magnitude of the load for different coating operations.

Growing community of inventors

Kingston, Canada

Robert Arthur Innes