US3627564A - Method for coating a continuous web - Google Patents

Method for coating a continuous web Download PDF

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US3627564A
US3627564A US55323A US3627564DA US3627564A US 3627564 A US3627564 A US 3627564A US 55323 A US55323 A US 55323A US 3627564D A US3627564D A US 3627564DA US 3627564 A US3627564 A US 3627564A
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Prior art keywords
web
blade
coating
coating composition
layer
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US55323A
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Joseph A Mercier
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Eastman Kodak Co
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Eastman Kodak Co
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C9/00—Apparatus or plant for applying liquid or other fluent material to surfaces by means not covered by any preceding group, or in which the means of applying the liquid or other fluent material is not important
    • B05C9/06—Apparatus or plant for applying liquid or other fluent material to surfaces by means not covered by any preceding group, or in which the means of applying the liquid or other fluent material is not important for applying two different liquids or other fluent materials, or the same liquid or other fluent material twice, to the same side of the work
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C3/00—Apparatus in which the work is brought into contact with a bulk quantity of liquid or other fluent material
    • B05C3/18—Apparatus in which the work is brought into contact with a bulk quantity of liquid or other fluent material only one side of the work coming into contact with the liquid or other fluent material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C5/00—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work
    • B05C5/007—Slide-hopper coaters, i.e. apparatus in which the liquid or other fluent material flows freely on an inclined surface before contacting the work
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C5/00—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work
    • B05C5/02—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work the liquid or other fluent material being discharged through an outlet orifice by pressure, e.g. from an outlet device in contact or almost in contact, with the work
    • B05C5/0254—Coating heads with slot-shaped outlet
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/07—Flat, e.g. panels
    • B29C48/08—Flat, e.g. panels flexible, e.g. films
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/16—Articles comprising two or more components, e.g. co-extruded layers
    • B29C48/18—Articles comprising two or more components, e.g. co-extruded layers the components being layers
    • B29C48/21—Articles comprising two or more components, e.g. co-extruded layers the components being layers the layers being joined at their surfaces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/30—Extrusion nozzles or dies
    • B29C48/305—Extrusion nozzles or dies having a wide opening, e.g. for forming sheets
    • B29C48/307—Extrusion nozzles or dies having a wide opening, e.g. for forming sheets specially adapted for bringing together components, e.g. melts within the die
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
    • D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
    • D21H23/22—Addition to the formed paper
    • D21H23/46—Pouring or allowing the fluid to flow in a continuous stream on to the surface, the entire stream being carried away by the paper
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
    • D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
    • D21H23/22—Addition to the formed paper
    • D21H23/70—Multistep processes; Apparatus for adding one or several substances in portions or in various ways to the paper, not covered by another single group of this main group
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H5/00—Special paper or cardboard not otherwise provided for
    • D21H5/0005—Processes or apparatus specially adapted for applying liquids or other fluent materials to finished paper or board, e.g. impregnating, coating
    • D21H5/0042—Processes or apparatus specially adapted for applying liquids or other fluent materials to finished paper or board, e.g. impregnating, coating by pouring or allowing to flow in a continuous stream onto the surface, the entire stream being carried away by the paper
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H5/00—Special paper or cardboard not otherwise provided for
    • D21H5/0005—Processes or apparatus specially adapted for applying liquids or other fluent materials to finished paper or board, e.g. impregnating, coating
    • D21H5/005—Processes or apparatus specially adapted for applying liquids or other fluent materials to finished paper or board, e.g. impregnating, coating involving several different techniques of application
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/74—Applying photosensitive compositions to the base; Drying processes therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C11/00—Component parts, details or accessories not specifically provided for in groups B05C1/00 - B05C9/00
    • B05C11/02—Apparatus for spreading or distributing liquids or other fluent materials already applied to a surface ; Controlling means therefor; Control of the thickness of a coating by spreading or distributing liquids or other fluent materials already applied to the coated surface
    • B05C11/04—Apparatus for spreading or distributing liquids or other fluent materials already applied to a surface ; Controlling means therefor; Control of the thickness of a coating by spreading or distributing liquids or other fluent materials already applied to the coated surface with blades

Definitions

  • Naramore ABSTRACT Two or more low-coverage coatings are applied substantially simultaneously to a web travelling at high speed by first trowelling a very thin subcoat onto the web with a trailing blade coater to prepare the web surface for an overcoating of the same or compatible coating material, and then flowing the overcoat down the top side of the trailing blade and off the trowelling end thereof directly onto the subcoat. Two or more layers of fluid coating composition can be flowed down the top of the trailing blade and onto the trowelled subcoat in distinct layer relationship with each other and the subcoat.
  • the present invention relates to coating a continuous web, and particularly to a method and apparatus for applying very low coverage with reasonable uniformity in thickness to a web travelling at high speed.
  • Slide coaters have been used in the art of coating photographic films or plates and wherein the emulsion flows down an inclined surface which extends from a hopper to the surface to be coated, see U.S. Pat. No. 401,771.
  • U.S. Pat. No. 2,761,417 shows a multiple slide hopper by means of which two or more layers of fluid coating composition can be simultaneously applied to a continuous web in distinct layer relationship. While these slide coating techniques are capable of applying reasonably uniform coatings to a continuously moving web, they are somewhat limited in coating speed because at high speed air tends to become entrained beneath the coating as it comes off the slide or is coated from a bead, as the case may be.
  • the primary object of the present invention is to provide a method of coating which combines the trailing blade and slide methods of coating in such a way as to overcome the shortcomings of both and provide a method by which one or more coating compositions of very low coverages and of reasonable thickness uniformity can be applied to a continuous web at high speeds.
  • Another object is to provide a method of applying very low coverage coatings to a web travelling at high speed which consists in first troweling a very thin subcoat onto the web surface with a trailing blade coater to prepare the surface for an overcoating of the same or compatible coating material, and then flowing the overcoat down the top side of the trailing blade and off the troweling end thereof directly onto the subcoat.
  • a further object is to provide a method of coating as described above by the use of which two or more layers of fluid coating composition(s) can be flowed down the top surface of the trailing blade and be flowed directly onto the trowelled subcoat in distinct layer relationship with each other and the subcoat.
  • Yet another object is to provide a novel coating apparatus for carrying out the above-described methods of coating, and which l have chosen to designate as a trailing blade slide coater.
  • FlG. 1 is a schematic view of a conventional trailing blade coater, and showing the system parameters thereof;
  • FIG. 2 is a side view, partly in section, showing a two-layer trailing blade slide coater constructed in accordance with one embodiment ofthe present invention
  • FlGS. 3 and 4 are views similar to FIG. 2, but showing other ways in which the undercoat or subcoat may be applied to the web;
  • FIG. 5 is a view similar to FlGS. 2-4, but showing another embodiment of the apparatus adapted to apply three layers of coating to a web in distinct layer relationship;
  • FIGS. 6, 7 and 8 are schematic views showing different blade edge geometries on an enlarged scale.
  • the present method of applying a reasonably uniformly thin layer of a given coating solution to the surface of a web moving continuously at high speed comprises the steps of applying a fluid composition to the surface of the web, troweling said composition as a subcoating on the web surface by moving the web past the end of a flexible stationary blade pressing against the web surface to fill any low areas in the web surface and providing a smooth wet surface on the web; then continuously metering a given quantity of said fluid composition, or another coating composition compatible with said subcoat, in the form of a layer onto the uppermost surface of said trailing blade at a point spaced above the flexible end thereof, said layer of coating composition, under the influence of gravity, flowing down said trailing blade to form a uniformly thin layer which ultimately flows off the end of the blade and onto the surface of the subcoat; and then simultaneously curing the subcoat and the thin layer of fluid coating composition.
  • Two or more layers of fluid composition may be simultaneously applied to the subcoat in distinct layer relationship with each other and the subcoat if desired.
  • the blade applied subcoat acts as a seal to prevent air entrainment under the subcoat(s) which is a major problem in slide or bead coaters when operating at high speeds.
  • the moving liquid layer(s) flowing off the trailing edge of the blade also acts to improve the blade operation by preventing drying of coating material on the blade edge.
  • a conventional blade coater is sche matically shown to clarify the system parameters of such a coater as they apply to the present invention as will be described below.
  • the web, W, to be coated is supported in a smooth condition on the surface of a coating roll 10 moving in a counterclockwise direction as shown by arrow 11.
  • the web to be coated may be raw paper, precoated paper, plastic film base, etc. Riding on the exposed surface of the web W as it moves around said coating roll is the flexible end 12 of a trailing blade 13 whose other end 13" is clamped, or otherwise fastened, to a rigid support 14.
  • the trailing blade may be made of any suitable springy material, e.g., stainless steel, blue steel, etc., but it should be made of a material which will not be readily corroded by the fluid composition to be used and should be of such hardness that the trailing edge will not be unduly worn away by the rubbing contact it has with the web.
  • the surface of the coating roll 10 may be metal or it may have a resilient surface which is engaged by the web.
  • the amount of coating composition which will flow past the blade will also depend upon the physical characteristics of the coating composition. It will be appreciated that unless a perfectly flat web is moving past the trailing blade the thickness of the coating trowelled onto the web will not be uniformly thick. in other words, a trailing blade coater is primarily useful only in filling the lower areas of a web surface and conditioning the web surface so that it is smooth.
  • a trailing blade slide coater for applying two layers of coating solution to the surface of a web, and constructed in accordance with one embodiment of the present invention, is shown and will be described.
  • the object here is to obtain a layer of a fluid coating composition on the web which is thin and uniformly thick.
  • a subcoat is first applied to the web surface by a trailing blade coater to provide a smooth wet surface on the web onto which the final coating of desired uniform thickness is applied and/or to condition the surface of the web to receive and hold the final overcoat.
  • This subcoat can be the same composition as the overcoat, or it can be a different composition, If it is a different coating composition, then the only requirement is that it be compatible with the overcoat composition so that the overcoat layer(s) will readily spread and adhere to the subcoat and not be adversely affected by the subcoat subsequent to their application.
  • the web W is held in wrapped relation with a coating roller ill to keep it smooth as it approaches and passes the coating point,
  • a trailing blade 13' is clamped between two sections l6 and i7 ofa coating hopper held together by suitable means, e.g. bolts (not shown).
  • the hopper section 17 is provided with a cavity 18, one wall of which is defined by the clamped-end E3" of the trailing blade.
  • the fluid subcoat composition, Sc is fed into the cavity 18 through an inlet 19 by a pump P.
  • the subcoat composition exits in a layer L through a discharge slot 20, the upper side of which is defined by the lower side of the trailing blade.
  • the layer L of the subcoat composition flows down the under side of the trailing blade to form a puddle or bead 21 extending completely across the deflected end 12 of the blade and between it and the web.
  • a puddle or bead 21 extending completely across the deflected end 12 of the blade and between it and the web.
  • This trowelling action of the blade provides a smooth wet surface on the web since the blade causes the subcoat to flll in the low areas of the web and scrapes clean the high points.
  • overcoat composition c As the overcoat composition c, is fed into the cavity at a constant rate it will exit from the discharge slot 24 in the form of a ribbon or layer onto the uppermost surface of the downwardly inclined trailing blade down which it flows by gravity to form a layer L
  • the deflected end 12' of the trailing blade intersects the web surface at an obtuse angle so that the layer l1. of overcoat flowing off the end thereof will flow onto the layer of subcoat in such a way as to maintain a distinct layer relationship between the two.
  • This distinct layer relationship between the two coatings is not important if the two coating compositions are of the same material. but it is important in certain cases where the coating compositions are different and a distinct layer relationship between them is desired, eg in certain photographic color materials where the several color sensitive and filter layers must be applied in distinct layer relationship.
  • the method used in applying the subcoat solution was found to have a major influence on the coating procedure.
  • the method of application best suited for a particular situa tion depends mainly upon the properties of the subcoat composition to be applied, as will be more fully set forth below.
  • FIG. 3 shows a two-layer coating system similar to that shown in FIG. 2 but having a different type of subcoat applicator,
  • the subcoat composition is applied to the web surface ahead of the trailing blade 13' from a manifold applicator 30 extending transversely of the web and having one, or more, inlets 3ll into which the fluid coating composition is fed by a pump, not shown.
  • the manifold applicator is provided with a plurality of discharge openings 32 spaced along its length through which the coating material issues in the form of individual streams spaced across the width of the web surface. These streams of coating material deposited on the web build up into a puddle 21 behind the trailing blade, said puddle serving to distribute the coating material uniformly across the web immediately ahead of the blade.
  • MG. 4 shows another embodiment of a two-layer system similar to that shown in FIGS. 2 and 3 but having a different type of subcoat applicator.
  • the subcoat is supplied from a reservoir-type applicator 35 wherein a relatively large quantity of coating material is maintained on the web surface immediately behind the deflected end 12' of the trailing blade 13'.
  • the coating material is fed into this reservoir through an inlet 36 by means of a pump not shown.
  • the present method of coating a web can be used to simultaneously apply a plurality of different fluid coating compositions in distinct layer relationship at high speeds.
  • FIG. 5 an embodiment is shown which is suitable for applying three different layers of coating composition onto a web surface at the same time.
  • the web W to be coated is passed around a coating roll 10 in a counterclockwise direction and its surface is engaged by the deflected end 12 of trailing blade 13' clamped between two sections 16 and 17 of a hopper.
  • the fluid coating composition, Sc which is to form the subcoat is fed onto the web surface ahead of the trailing blade 13' from a plurality of tubes 60, only one of which is shown, spaced across the web.
  • the subcoat material is fed into these tubes by a pump, not shown, and the streams of coating reaching the backside of the deflected end of the trailing blade merge into a puddle 21' from which the material flows under the blade and is trowelled into a layer L on the web surface thereby.
  • the fluid coating composition, Sm which is to form the middle coat is pumped into a cavity 22 in the hopper section 16 by a constant discharge pump and issues therefrom through a discharge slot 24' in the form of a layer L, which is directed onto the uppermost surface of the trailing blade.
  • the fluid coating composition, St which is to form the top coat is fed into a cavity 42 in another hopper section 43 by a pump of the constant discharge type.
  • This coating composition issues in the form of a layer L from a discharge slot 45 defined by a surface 46 on the hopper section 43 spaced from the top of hopper section 23'. This layer flows down the inclined surface 47 of hopper section 23 and onto the top of the layer L, of the middle coat issuing from cavity 22'.
  • the two layers L and L then flow down the uppermost surface of the trailing blade in distinct layer relation and flow of? the end of the blade onto the layer L of subcoat while still maintaining a distinct layer relationship with each other and the subcoat.
  • the final thickness of the individual layers L, and ls are determined, not by the width of the discharge slots through which they issue from and supply cavities 22' and 42, respectively, but by the rate at which they are pumped into their respective cavities.
  • the coverage thickness of the subcoat will depend upon the smoothness of the web surface. the physical properties of the coating composition used and the pressure exerted by the trailing blade in trowelling the coating.
  • FIGS. 6, 7 and 8 show these types of edge geometries used in trials of this method and apparatus of coating.
  • the blade edge shown in FIG. 8 was found to be best suited for use with the trailing blade slide coater process.
  • the edge shown in FIG. 6 is well suited for applying overcoat layers since the sharp edge makes it easy for the overcoat composition(s) to slide onto the web surface.
  • a disadvantage of this type of blade edge is its high sensitivity to any paper fibers (if the web is a raw paper stock) or foreign particles that may be present on the web surface. The fibers and foreign particles are retained at the blade edge and cause streaks in the coating. The sharp edge blade tends to wear quickly causing additional problems.
  • the blade edge as shown in FIG. 7 is well suited to applying a blade coat to a continuous web.
  • the rounded edge will apply a coating that has a good finish, and it is not largely influenced by dirt and paper fibers.
  • a disadvantage with this blade is that it becomes extremely difficult to slide and overcoat ofi the blade and onto a continuous web.
  • the blade as shown in FIG. 8 is a compromise between those shown in FIGS. 6 and 7. It is designed to utilize the advantages of both the knife edge blade and the rounded edge blade.
  • the coating and trailing blade angles (see FIG. I) had no major influence on the coating technique. Both angles were varied through large ranges.
  • the trailing blade slide coating technique has been evaluated on a commercial coating machine using aqueous solutions of gelatin, methanol solutions of polyvinyl acetate (hereinafter referred to as PVA), aqueous solutions of carboxymethyl cellulose (hereinafter referred to as CMC) and aqueous dispersions of baryta and aqueous dispersions of claycasein as the blade coated materials.
  • Aqueous solution of gelatin, PVA and CC were also used for the slide coat. Satisfactory coverages ranged from 0.06 to 1.40 lb./l ft. for the slide coat and 0.08 to 0.50 lb./l00 ft. for the blade coat.
  • Coating speeds ranged from 200 to 1,030 ft./min., this high speed being the upper limit which the machine used was capable of.
  • dyes were mixed into the coating fluids so that various layers of a coating sample could be differentiated.
  • a raw paper stock was used as the continuous web. Paper coated with polyethylene or baryta were also tried in order to determine 5 the effect of precoated paper webs on this coating technique.
  • Table 1 lists trials in which only the blade coat, or subcoat, was applied to the continuous web.
  • Table 2 lists trials in which the blade coat and the overcoat (slide coat) were applied simultaneously.
  • Triple coats applied in a like manner are listed in table 3.
  • Table 4 gives the viscosities for the fluid compositions used.
  • Viscosity testing temperature l00 F.
  • Aqueous Gelatin Solutions in contrast to elastic solids, most liquids are considered to possess no elasticity or rigidity when sheared and should respond immediately to any attempt made to deform them. There are, however, liquids that generate measurable normal stresses when sheared and show both viscous and elastic effects. These liquids are called viscoelastic solutions or dispersions.
  • the CMC (3 percent to 8 percent solids) worked well as a subcoat solution. This material exhibits the same shear thinning qualities as the high-solids clay and baryta materials.
  • Overcoat (blade coat) Fluid Compositions A. Gelatin The solids content of the gelatin solutions used for the overcoat ranged from 5 percent to 18 percent. All mixtures that were used worked very well. In some instances, a wetting agent was added to these mixtures to improve their wetting qualities. Although other wetting agents probably could have been used satisfactorily, the one used was that sold under the trademark Triton X-200 and having the chemical name P- l, l 33-tetramethylbutyl) phenoxyethoxyethyl sodium sulfonate.
  • the PVA mixtures l2 percent and 20 percent) solids were found to be good overcoat fluids. There was some slight difficulty in coating this fluid composition because of its quickdrying characteristics.
  • the 3 percent solids CMC was a very poor overcoat solution.
  • the material would not distribute evenly as it was transferred from the blade to the continuous web and acted much like an elastic material. This problem was found to be characteristic of the CMC solution and not a limitation of the trailing blade slide coater process.
  • the 8 percent solids CMC was not tried as an overcoat fluid due to the problems associated with the lower solids mixture.
  • Microsections of the three-layer coatings were examined to determine if the coating techniqge was capable of applying two overcoat layers that would remain separated after drying.
  • the apparatus used in applying the three layer coatings is shown in FIG. 5 and the data of the test is detailed in table 3.
  • the sections examined showed separation of the three layers from one another.
  • the trailing blade slide coating process was tested at speeds ranging from 200 to 1,030 feet per minute.
  • the upper limit is not the coating process limit but the maximum speed at which the machine on which the tests were made could be safely run. Based on experimental tests, it can be stated that the trailing blade slide coating process is capable of speeds in excess of 1,000 feet per minute.
  • the hoppers shown in FIGS. 2-5 could be made from a single block of material, in order to facilitate the fabrication of the same and to make it possible to clean it out when it is desired to change from one coating composition to another, it is more practical to make the hopper up from a number of separate sections, as shown, which can be readily assembled and disassembled. lt should also be mentioned that if the coating compositions are of such a nature that they to be heated or cooled while in the hopper in order to keep them in a suitable condition for flow, then the hopper sections may be provided with bores through which a heating or cooling liquid may be circulated, as is well known in the art.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Coating Apparatus (AREA)
US55323A 1970-07-16 1970-07-16 Method for coating a continuous web Expired - Lifetime US3627564A (en)

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Cited By (25)

* Cited by examiner, † Cited by third party
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DE2309158A1 (de) * 1972-02-24 1973-09-13 Eastman Kodak Co Verfahren zur simultanbeschichtung von schichttraegeroberflaechen
US3928678A (en) * 1973-01-26 1975-12-23 Eastman Kodak Co Method and apparatus for coating a substrate
US3928679A (en) * 1973-01-26 1975-12-23 Eastman Kodak Co Method and apparatus for coating a multiple number of layers onto a substrate
US3993019A (en) * 1973-01-26 1976-11-23 Eastman Kodak Company Apparatus for coating a substrate
US3996885A (en) * 1973-01-26 1976-12-14 Eastman Kodak Company Apparatus for coating a multiple number of layers onto a substrate
US4106437A (en) * 1977-08-22 1978-08-15 Eastman Kodak Company Apparatus for multiple stripe coating
US4143190A (en) * 1977-01-27 1979-03-06 Polaroid Corporation Method and apparatus for coating webs
US4345970A (en) * 1979-02-28 1982-08-24 The Wiggins Teape Group Limited Process and apparatus for controlling the deposition of a liquid on to a moving surface
US4442144A (en) * 1980-11-17 1984-04-10 International Business Machines Corporation Method for forming a coating on a substrate
US4668329A (en) * 1984-03-08 1987-05-26 Tokai Shoji Co., Ltd. Method and an apparatus for applying an emulsion onto a screen-printing plate
EP0378914A3 (en) * 1989-01-19 1990-10-24 Oji Paper Co. Ltd. Process for the preparation of support sheet for photographic printing paper
US5044305A (en) * 1988-06-07 1991-09-03 Fuji Photo Film Co., Ltd. Curtain-type coating device
EP0575879A3 (enrdf_load_html_response) * 1992-06-24 1994-03-16 Du Pont
US5728430A (en) * 1995-06-07 1998-03-17 Avery Dennison Corporation Method for multilayer coating using pressure gradient regulation
US5741549A (en) * 1994-04-29 1998-04-21 Maier; Gary W. Slide die coating method and apparatus with improved die lip
EP0849396A1 (de) * 1996-12-18 1998-06-24 Voith Sulzer Papiermaschinen GmbH Auftragwerk zum direkten oder indirekten Auftragen eines flüssigen oder pastösen Auftragmediums auf eine laufende Materialbahn, insbesondere aus Papier oder Karton
US5851289A (en) * 1995-11-21 1998-12-22 Sony Corporation Applicator
US5962075A (en) * 1995-06-07 1999-10-05 Avery Dennison Method of multilayer die coating using viscosity adjustment techniques
US6217940B1 (en) * 1996-11-04 2001-04-17 Valmet Corporation Method and apparatus for coating a moving paperboard web
US20030124254A1 (en) * 2001-12-27 2003-07-03 Rexam Image Products, Inc. Wet on wet process for producing films
US6699326B2 (en) 2000-09-22 2004-03-02 Regents Of The University Of Minnesota Applicator
US6824828B2 (en) 1995-06-07 2004-11-30 Avery Dennison Corporation Method for forming multilayer release liners
WO2005092514A1 (de) * 2004-02-18 2005-10-06 Basf Aktiengesellschaft Verfahren und vorrichtung zum aufbringen mindestens zweier chemisch unterschiedlicher fliessfähiger medien
US20060096529A1 (en) * 2004-11-05 2006-05-11 Hon Hai Precision Industry Co., Ltd. Slide hopper and multilayer coating apparatus having the same
US20080075837A1 (en) * 2004-10-29 2008-03-27 Bower Christopher L Method of pattern coating

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US4113903A (en) * 1977-05-27 1978-09-12 Polaroid Corporation Method of multilayer coating
GB2006977B (en) * 1977-10-14 1982-02-24 Eastman Kodak Co Manufacture of coated paper
DE10012344A1 (de) * 2000-03-14 2001-09-20 Voith Paper Patent Gmbh Vorhang-Auftragsverfahren

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US2932855A (en) * 1956-09-11 1960-04-19 Eastman Kodak Co Method for forming film or sheeting
US3442684A (en) * 1963-11-27 1969-05-06 Int Paper Co Bent blade clay coating

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US2932855A (en) * 1956-09-11 1960-04-19 Eastman Kodak Co Method for forming film or sheeting
US3442684A (en) * 1963-11-27 1969-05-06 Int Paper Co Bent blade clay coating

Cited By (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2309158A1 (de) * 1972-02-24 1973-09-13 Eastman Kodak Co Verfahren zur simultanbeschichtung von schichttraegeroberflaechen
US3928678A (en) * 1973-01-26 1975-12-23 Eastman Kodak Co Method and apparatus for coating a substrate
US3928679A (en) * 1973-01-26 1975-12-23 Eastman Kodak Co Method and apparatus for coating a multiple number of layers onto a substrate
US3993019A (en) * 1973-01-26 1976-11-23 Eastman Kodak Company Apparatus for coating a substrate
US3996885A (en) * 1973-01-26 1976-12-14 Eastman Kodak Company Apparatus for coating a multiple number of layers onto a substrate
US4143190A (en) * 1977-01-27 1979-03-06 Polaroid Corporation Method and apparatus for coating webs
US4106437A (en) * 1977-08-22 1978-08-15 Eastman Kodak Company Apparatus for multiple stripe coating
US4345970A (en) * 1979-02-28 1982-08-24 The Wiggins Teape Group Limited Process and apparatus for controlling the deposition of a liquid on to a moving surface
US4427491A (en) 1979-02-28 1984-01-24 The Wiggins Teape Group Limited Apparatus for controlling the deposition of a liquid on to a moving surface
US4442144A (en) * 1980-11-17 1984-04-10 International Business Machines Corporation Method for forming a coating on a substrate
US4668329A (en) * 1984-03-08 1987-05-26 Tokai Shoji Co., Ltd. Method and an apparatus for applying an emulsion onto a screen-printing plate
US5044305A (en) * 1988-06-07 1991-09-03 Fuji Photo Film Co., Ltd. Curtain-type coating device
EP0378914A3 (en) * 1989-01-19 1990-10-24 Oji Paper Co. Ltd. Process for the preparation of support sheet for photographic printing paper
EP0575879A3 (enrdf_load_html_response) * 1992-06-24 1994-03-16 Du Pont
US5741549A (en) * 1994-04-29 1998-04-21 Maier; Gary W. Slide die coating method and apparatus with improved die lip
US5728430A (en) * 1995-06-07 1998-03-17 Avery Dennison Corporation Method for multilayer coating using pressure gradient regulation
US6824828B2 (en) 1995-06-07 2004-11-30 Avery Dennison Corporation Method for forming multilayer release liners
US5962075A (en) * 1995-06-07 1999-10-05 Avery Dennison Method of multilayer die coating using viscosity adjustment techniques
US20050100677A1 (en) * 1995-06-07 2005-05-12 Avery Dennison Corporation Method for forming multilayer release liners and liners formed thereby
US20050074549A1 (en) * 1995-06-07 2005-04-07 Avery Dennison Corporation Method for forming multilayer release liners and liners formed thereby
US5851289A (en) * 1995-11-21 1998-12-22 Sony Corporation Applicator
US6217940B1 (en) * 1996-11-04 2001-04-17 Valmet Corporation Method and apparatus for coating a moving paperboard web
US5997646A (en) * 1996-12-18 1999-12-07 Voith Sulzer Papiermaschinen Gmbh Apparatus for direct or indirect application of a liquid or pasty coating medium onto a traveling material web, notably of paper or cardboard
EP0849396A1 (de) * 1996-12-18 1998-06-24 Voith Sulzer Papiermaschinen GmbH Auftragwerk zum direkten oder indirekten Auftragen eines flüssigen oder pastösen Auftragmediums auf eine laufende Materialbahn, insbesondere aus Papier oder Karton
US6699326B2 (en) 2000-09-22 2004-03-02 Regents Of The University Of Minnesota Applicator
US6824818B2 (en) 2001-12-27 2004-11-30 Soliant Llc Wet on wet process for producing films
US20030124254A1 (en) * 2001-12-27 2003-07-03 Rexam Image Products, Inc. Wet on wet process for producing films
WO2005092514A1 (de) * 2004-02-18 2005-10-06 Basf Aktiengesellschaft Verfahren und vorrichtung zum aufbringen mindestens zweier chemisch unterschiedlicher fliessfähiger medien
US20080075837A1 (en) * 2004-10-29 2008-03-27 Bower Christopher L Method of pattern coating
US20060096529A1 (en) * 2004-11-05 2006-05-11 Hon Hai Precision Industry Co., Ltd. Slide hopper and multilayer coating apparatus having the same
US7347898B2 (en) * 2004-11-05 2008-03-25 Hon Hai Precision Industry Co., Ltd. Slide hopper and multilayer coating apparatus having the same

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CH545690A (enrdf_load_html_response) 1974-02-15
JPS544982B1 (enrdf_load_html_response) 1979-03-12
CA943825A (en) 1974-03-19
DE2135438A1 (de) 1972-01-20
FR2101791A5 (enrdf_load_html_response) 1972-03-31
AU3127371A (en) 1973-01-18
BE770081A (fr) 1971-11-16
GB1358298A (en) 1974-07-03

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