Abstract:
Method and apparatus for coating a paper or paper board web including preventing deposition and drying of the coating paste on the edge zones of the coating chamber by continously causing a flow of coating paste from the coating chamber past the edge seal (2). Each edge seal is disposed in the space between the front and the rear walls (3, 4) of the coating apparatus, and the upper part (11) of each edge seal corresponds to the form of a wedge between the wiping member (9) of the coating apparatus and the web (12) to be coated. Coating paste flows through gaps (13, 14) between the edge seals and the wiping member and between the edge seals and the web, which gaps are 1-10 mm wide.
Abstract:
Improved installation (10), whereby in a first section (22) coating (24) is applied on substrate (14), moving through a passage (16) under double floating condition, in a following section (26) a layer fluid (28) is applied on said layer coating (24) and in the following sections (30) and (32) the removal takes place of said fluid layer with thereafter a drying of the remaining coating layer.
Abstract:
In the manufacture of photographic materials, for example photographic films, the production process in interrupted when the coating apparatus is cleaned. The new configuration utilizes several coating apparatus units. By means of a transfer device, such coating apparatus units can be moved from a standby zone, in which at least one casting unit is kept in readiness, into a coating zone in which a casting unit coats the substrate with one or more liquid coatings, and back. By means of the new configuration, production shutdowns arising from, for example, cleaning, repair or replacement of the coating apparatus, can be significantly shortened.
Abstract:
A method and apparatus of manufacturing a web which is striped with add-on material, comprising: a first arrangement which establishes a sheet of base web from a first slurry and moves the established sheet along a first path; a second arrangement for preparing a second slurry; a moving orifice applicator operative so as to repetitively discharge the second slurry upon the moving sheet of base web, the moving orifice applicator comprising: a chamber box arranged to establish a reservoir of the second slurry across the first path; an endless belt having an orifice, the endless belt received through the chamber box; a drive arrangement operative upon the endless belt to continuously move the orifice along an endless path and repetitively through the chamber box, the orifice when communicated with the reservoir being operative to discharge the second slurry from the reservoir through the orifice; a flow distribution system for introducing the second slurry into the chamber box at spaced-apart feed locations along the chamber box; a flow monitoring system for reading fluid pressure at spaced-apart locations along the chamber box; and a controller arranged to identify which of the feed ports is operatively adjacent a monitored location of highest pressure variation, the controller selectively adjusting output of the flow distribution system at the identified feed location counteractively to the highest pressure variation, the controller adjusting output of a remainder of the feed locations counteractively to the output adjustment at the identified feed location.
Abstract:
An apparatus (10) that comprises a body (12) including a reservoir (16) adapted for receiving a quantity of fluid and a plurality of fluid distribution channels (18) each having a length and a cross-sectional area and being in fluid communication with and extending from the reservoir (16) from a first end and terminating at a second, distal end in an orifice. The apparatus (10) further comprises a distribution chamber (22) in the body for commonly receiving the fluid exiting each of the orifices, for merging the fluid exiting each of the orifices into at least one continuous coating stream, and for equalizing the pressure of the fluid, the distribution chamber (22) having a first side in fluid communication with the plurality of fluid distribution channels (18) and a second side that is open to allow the fluid to exit the body for uniform distribution onto the web. In addition, the apparatus comprises a smoothing surface on the body adjacent the second side of the distribution chamber (22) to smooth the fluid on the moving web as the fluid exits the second side of the distribution chamber and is deposited on the moving web and a fluid supply means for supplying fluid to the reservoir (16) and for maintaining the fluid under pressure in the reservoir, whereby the fluid moves under pressure from the reservoir through the fluid distribution channels to the first side of the distribution chamber, through the distribution chamber to exit the second side of the distribution chamber, and onto the moving web.
Abstract:
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.
Abstract:
A die coating method and apparatus includes a die (100, 150, 220) having an upstream bar (104, 154, 226) with an upstream lip, a central bar, a downstream bar (108, 158, 232) with a downstream lip, and a vacuum bar (110, 160, 224). The upstream lip is formed as a land and the first manifold bar is formed as a sharp edge. The shape of the land conforms to the shape of the surface being coated. Changing at least one of the slot heights H, the overbites O, and the convergence C can improve coating performance. The die can have a slide surface (236, 244) and the coating fluid can exit the die from a passageway and slides along the slide surface to form a continuous coating bead between the manifold bar sharp edge, the upstream die lip, and the surface being coated. The die can include several passageways for coating multiple layers.
Abstract:
A cross flow knife coater (10, 10') includes a coating station (16) through which a surface passes and a trough (18) which extends transversely across the desired width of the coating. The trough (18) has an opening (26) through which coating fluid (30) exits onto the surface without using a slot, and first and second transverse ends. The coating fluid (30) is fed directly into the trough (18) at a first transverse end, and is moved from the first transverse end of the trough, across the trough, and toward the second transverse end to cause the coating fluid to flow across the width of the trough while coating fluid exits the opening. The coater (10, 10') creates a spiral flow of coating fluid (30) across the width of the trough (18) which carries debris, bubbles, and other undesirables across the trough to a second traverse end where they can be vented. The perpendicular distance between the trough opening (26) and the surface, and likewise between the knife (28) and the surface, can be adjusted.
Abstract:
An applicator unit (100) is disclosed for applying glue or another fluid medium on a substrate (36). The housing (10) is subdivided into a glue guiding part (2) and into a driving part (1) that receives a piezoelectric element (20). A valve member (30) arranged in the glue guiding part (2) may be moved in the direction of an axis (11) and forms a glue discharge valve (40). The glue discharge valve (40) is normally closed by a stack of disk springs (25) that stresses the valve member (30). When a voltage, resulting in an expansion, is applied to the piezoelectric element (20), said element moves the valve member (30) against the force of the stack of disk springs (25) and opens the glue discharge valve (40). In order to avoid heat transmission from the hot glue guiding part (2) to the driving part that contains the piezoelectric element (20), the parts (1, 2) are mutually separated by a heat insulating zone (3).
Abstract:
The invention concerns a method for the metered application of liquids to material webs, in particular to films. The problem addressed by the invention, which is to avoid the disadvantages of the prior art and to develop a method for the metered application of liquids to material webs wherein a homogeneous coating is produced with minimal pollution, is solved by the fact that the material web (4) to be coated is conveyed over the surface of an ultrasonic vibration system (1) which, in step with the set operating frequency, generates between the material web (4) and the surface of the vibration system (1) a periodically opening gap (5) via which the liquid is applied to the material web (4).