Патент USA US2406057код для вставки
Aug. 0, 3945. w. H. ARRETT ET AL. COATING APPARATUS Eiled NOV. 30, 1944 3 SheeiIZS-Sheei‘ 1 (‘1.,I lrweniowg. William H. Boar-refit vIBewm‘ar-al KAsoieH. 'télrneg. a _uga 2%, i ZAQ? ' \N. H. BARRETT ET AL COATING APPARATUS Filed Nov. '50, 1944 5 Sheets-Sheet 2 . 5. .FL IJ‘ . Eermm'd K AsdelL " TQR N ‘I Aug. 2@, 1946; _ W, H, BARRETT ET AL I _ ' 7 2,406,057 COATING APPARATUS ' Filed Nov. so, 1944 s Sheets-‘Sheet s INVENTORS: Wmlliqm HjBarr-ejl‘f. BY Bernard K‘Asdell ATTORNEY ‘ ' 2,405,057 Patented Aug. 20, 1946 UNHTEDV STATES PATENT OFFICE 2,406,057 COATING APPARATUS William newer: and Bernard K. Asdell, Inter-‘ national Falls, Minn, assignors to Minnesota and Ontario Paper Company, Minneapolis, Minn. Application November 30, 1944, Serial No. 565,926 12 Claims. (Cl. 91-49) 1 2 This invention relates to the art of coating sheet material and more particularly to coating tinuous manner while moving at high rates of Figure 4 is a sectional view‘with parts broken away of the‘ fountain which shows the lower‘ nip formed by the applicator roll and the metering roll having an excess of coating material therein; speed. and webs of paper which can be processed in a con There are numerous methods of coating a web material such as paper having the desired ob Figure 5 is a view of the back of the fountain ject of applying coating that will be smooth, uni shown in Figures 2 and 3. Referring to the drawings in detail: [0 indi form in appearance, and of a desired Weight or cates a web of paper coming from a source not thickness. 10 shown; the web of paper passes roll II and then roll l2- and then into contact with the backing It is an object of this invention to provide an means or drier roll 13. The coating material to apparatus which will apply such a ?lm of coat be applied to the web of paper on the backing ing material to a web of paper traveling upwards means 13 is supplied to a fountain l4 and the of two thousand feet per minute. By the term paper as used herein, it is intended to include 15 surplus coating material from the fountain flows over the back side ‘of the fountain and into a any and all materials in sheet form wherein a container 23. A resilient surfaced applicator roll, coating may be applied and treated in accord I6 is so mounted that it contacts the paper upon the backing means and dips into the fountain Another object of this invention is the pro vision of a coating unit so arranged that the 20 l4. Mounted in the fountain at a selected dise tance from the applicator r011 I6 is metering coating materials having wide variations in solid roll I5 and it is generally preferred that the me content may be applied to a fast moving web of tering roll be a hard surfaced unit. This meter paper in a predetermined weight per unit of ance with this invention. paper. The coating apparatus disclosed in co-pending application, Serial No. 511,753, ?led November 24, 1943, provides an excellent coating on the pa per, but it has the disadvantage that at speeds upward of two thousand feet when coating pa ing roll controls the amount of coating material which is carried by the applicator roll l6. Im mediately above the applicator roll at a selected distance therefrom is mounted a hard surfaced doctor roll IT. This doctor roll removes a por tion of the coating material on the applicator per of over one hundred inches in width that the 30 roll I6 and smooths upon the' applicator roll’s doctor roll tends to de?ect. The deflection of the doctor roll at high speed tends to result in an uneven coating across the width of the sheet of paper. It has been discovered that if the doctor periphery the coating material remaining there apparatus; that herein described. on. The doctor roll I‘! is generally a hard sur faced roll and has its periphery wiped substan tially clean by‘ a resilient surfaced roll 18 which roll is supported between the rolls, the problem 35 is mounted immediately above the doctor roll. To remove the coating from the resilient surfaced of de?ection at high speed is substantially if not roll, a doctor blade I9 is provided. The coating completely overcome. material removed by the doctor blade is returned Additional features of the invention reside in through troughelike member“ and pipe 2| to the coating fountain, the applicator roll, and pro visions whereby pressure applied to the appli 40 coating container 23. The coating material in the container 23 is withdrawn by pump 25 and cator roll and the doctor roll can be determined forced through pipe 26 and into fountain [4 ad and controlled. The invention has numerous jacent the top of the fountain. ‘ other features which will be hereinafter described When applying coating of ten pounds or more in detail and particularly pointed out in the 45 per side to a web of paper, it is preferred that appended claims. such coating be applied in two applications rather In the drawings forming a part of this inven than in a single application. As disclosed in Fig tion, similar reference numerals indicate corre ure 1, coating units generally indicated at 40,. sponding parts in all the drawings in which: 4], 42, and 43 are of identical construction as Figure 1 is a side elevational view of a coating Figure 2 is a view of a modi?ed form of the ‘ The paper [0 after having the coating applied invention; by applicator roll I6 of coating unitlo' passes Figure 3 is a second modi?cation of the coat ing apparatus in which a nest of the driers are around a substantial portion of the surface of the drier l3. After the coating has'at least pre used in place of one large drier; 65 liminarily set, a felt is brought in contact with 2,406,057 3 4 the paper for a portion of its travel over the of coating material is maintained with a head drier surface. higher than the nip formed by the applicator Some of the reasons for the use of the felt is to prevent drier wrinkles, and to hold the paper in close contact with the drier surface. The felt passes over rolls 33, 34, and v 35 and 36 and then comes in contact with the coated paper. The felt leaves the surface of the roll and the metering roll. The excess coating from the fountain shown in Figure 1 is returned to the container by pipe 22. A resilient surfaced applicator roll l5 rotates into the fountain and picks up coating in excess to that to be applied to paper atrroll 28 and the paper and the felt travel the paper. A metering roll or doctor roll I5 which together over rolls 30, 3| and 32. is positioned at a selected distance from the ap The paper then receives its second ?lm on the 10 plicator roll surface l6 controls the amount of same side by coating unit 4| and then passes coating on the applicator roll. The coating on around drier roll 37. The paper leaves the drier the applicator roll after passing metering roll I5 roll at roll 46. The felt 154 contacts the paper on is smoothed and a portion removed by rotating a portion of its travel around the’ surface of the hard surfaced doctor roll H’. The hard surfaced drier 31 and this felt leaves the surfaceof the 15 doctor roll may be composed of various materials paper at roll 45 and then the paper and the felt travel together over rolls 41 and 48‘. The felt which is endless then passes over rolls 49, 59, ' and 5|. The paper continues over roll 52 and , then is carried by felt 53 over rolls 54, 55 and 56. 20 The felt 53 then travels over rolls 5T, 58, and 59. The coated paper after leaving felt 53 passes in contact vwith roll 60 and thenreceives its ?rst but it is‘ believed essential that the hardness of the doctor roll I1 be considerably harder than that of the resilient applicator roll IS. The coating material removed by doctor roll IT is wiped from the surface of this roll by resilient surfaced roll I8 and any coating material removed by the roll I8 is doctored therefrom and returned to the ' coating container. coating on the opposite side by coating unit 43. The rolls I6 and H are supported by upright The‘ coated paper travels around a substantial 25 member 85 which is pivoted at 84. The doctor - portion of the surface of the drier 39 and leaves roll I 5 is supported by a member which is pivoted the drier surface at roll 64. . The'felt 5! which at 91. ' The purpose of the pivot of doctor roll and the applicator roll is to permit separation of the applicator roll from the doctor roll and the doctor of the paper on the drier. The paper travels 30 roll from the drier surface. To control the with felt BI over rolls' 65, 65, and 6?. The end amount of pressure applied by metering roll or lessfelt?l then passes over rolls 59, ‘I0 and 62, doctor roll I5 to the resilient applicator surface then back in contact with the coated surface of I5 is a pressure adjusting rod 88 vsecured to the the paper. The paper after leaving the roll 6? metering roll support. This rod is connected passes around the surface of the drier 39 and 35 to an eccentric 89 and extending from this eccen contacts the paper on thes'urface 'of the ‘drier 39 passes 'over roll ‘63 after leaving the surface receives its second coating on the opposite side of the sheet by coating unit: 42. The coated tric 89 is'handle 99. By turning the handle 90 the pressure between the rolls I5 and I5 can be paper is contacted on a portion of the “drier sur controlled and varied. A member 9| is hingedly face 38. by felt ‘II. The felt parts. contact with connected to the member 85 at 92, and this mem the surface'of the coated paper at roll ‘I3. for a 40 ber'is pivotally connected to upright member 94 space ‘while the coated paper travels 'to and at 93. The upright member 94 is pivoted at one end of 95 and connected at the other end to around the roll ‘I4 and thereafter the felt and member 96. The member 96 is connected with paper pass over rolls 15, ‘I6, and ‘IT. The paper a hydraulic or other power cylinder 9'! for vary then passes over roll 8i to suitable means not shown, for winding in rolls; ‘ ' 4 ing the pressure of the coating unit against the drier surface. For supporting the roll I8 is mem ber 98 secured to the'roll‘ and pivotally secured to the upright member 94 at 99. For varying the In Figure 2 of the drawings, there‘is shown a modi?cation of the apparatus disclosed in Figure 1, and in this modi?cation, the paper I9 passes over rolls II and I2, and then into contact with pressure between the rolls I6, I7, and I8 there the surface of a heated drying roll. is provided a member I99 which connects mem The paper ber 9| and 98 through the medium of eccentric IIH. For turning the eccentric there is provided the drier roll leaves that surface and passes over a handle I92 whereby the pressure between these a jump roll ‘I03 and then back into contact with rolls may be varied and controlled. the drier surface. The paper leaves the surface Although the contact of the coated paper with of the drier at roll 29.' The coated surface of the the‘ drier surface in the modi?cation vshown in paper is contacted on aportion ‘of its travel over Figure 2 is less than that shown in Figure 1-, the the'd'rier surface with a positively driven felt. rate of speed of drying is expedited by the fact The purpose of this felt is to eliminate to a great that the steam generated in the drying coated extent, if not completely, the formation of drier wrinkles and also to hold the coated paper in 60 paper is permitted to be dissipated while the paper is out of contact with the drier surface. close contact with the drier surface. The endless In Figure 3 is shown another modi?cation felt leaves the surface of the coated paper and wherein the single drying roll is replaced by a passes over roll'28' where the coated paper and nest of drying rolls. The paper ID in this modi the felt travel together for a given distance. ?cation as it passes over roll Ila, which in some In the coating of paper on the felt side, it some cases is heated so as to bring the temperature of times occurs that, this surface of the paper is the paper to be coated to approximately the tem resistant'to the absorptionof moisture, and the perature of the coating material. In this modi moisture from the coating material does not uni ?cation, the backing roll I95 contacts the paper formly wet the‘ paper; This di?iculty may be as the coating is being applied by resilient roll IS. overcome by lightly brushing the surface of the The paper after being coated passes around the paper. This is accomplished‘, in Figure 2 by'_hav-' surface of drying rolls I06, I61, I98, and I09. 'At ing the surface of the paper lightly contacted with the surface of the roll I8. the drying roll I09, the coating surface of the pa The coating material is pumped from a suitable per is in contact with the heated surface. It is to coating container to a fountain wherein a pond, 75 be understood that the nest of rolls may vary‘ after traveling over 'a'portion of the surface of 5 6 in size from each other and in number depending uponthe amount of drying surface necessary to set the coating material.- Also, a nest of drying ceiving'coat-ing from the fountain, 'aimetering rolls has the advantage over a single drying roll in that it permits a controlled temperature to be used in the drying of the coatingmaterial. For example, the temperature on roll I06 may be from selected distance‘ therefrom, and a roll above the doctor roll and contacting the surface of the 225-275" F., while the temperature of roll I01 roll at a selected distance from the applicator roll, a doctor rollabove the applicator'roll at'a doctor roll. - ' 4. A coating apparatus comprising,- a backing roll, an applicator roll having a surface with re silient properties, a fountain having an open side may be varied from 275-325“ F., and the tem-' perature of the roll I08 may be varied from 325 10 directedtoward the applicator roll- so that the fountain and the‘ applicator roll form a coating 375° F. While the temperature‘ of the roll I09 container, a hard surfacev metering roll mounted may be considerably above the temperature of in the fountain at ‘a selected distance from the the other rolls without resulting in damage to applicator roll, a doctor roll above the applicator the coated surface. The coating material is sup roll at a selected distance therefrom, and a roll plied to the container 23 and this coating is re for cleaning thesurface of the-doctor roll. moved by pump 25 and passes through line 26 into .5. A coating unit including a, backing cylin the fountain M. A- sufficient head of coating drical» member, a fountain, an applicator roll re material is maintained in the fountain l4 so that ceiving coating from the fountain, a metering roll the lower nip of the metering roll and the ap plicator roll is ?ooded. Thisassures that foam 20 at a selected distance from the applicator roll, ing of the coating material will be substantially a doctor roll above the applicator roll, and at a if not entirely eliminated. The coating material on the resilient surfaced applicator roll 16 after selected distance therefrom, and means for sep arating the metering roll from the applicator roll, and means of separating the applicator roll and it passes the metering roll is smoothed and a , portion of it removed by hard surfaced doctor roll 25 the backing roll. 6. A coating apparatus comprising, a backing H. A portion of the coating material on the roll, an applicator roll with a surface having re surface of the doctor roll I1 is removed by re silient properties, a fountain having an open side silient surfaced roll M which has its surface directed toward the applicator roll so that the cleaned by a suitable doctor blade and the coat ing material so removed is returned to the coat 30 fountain and the applicator roll form a coating container, a metering roll mounted in the foun ing container 23. The direction of rotation of tain at a selected distance from the applicator the rolls is disclosed in Figure 3, and the direction roll, a doctor roll above the applicator roll and of rotation is the same in each of the apparatus shown. It may be pointed out that the surplus at a selected distance therefrom, a roll above the coating material is pumped to the fountain and 35 doctor roll for cleaning the surface of the doc tor roll, and means for cleaning the surface of the back of the fountain is lower than the side the roll cleaning the surface of the doctor roll. walls for permitting the coating material to flow '7. A coating apparatus comprising, a backing over the back of the fountain l4 and return to roll, an applicator roll for transferring coating the coating container 23. When using mineral-adhesive coating material 40 material to a moving web of paper, a fountain having an open side directed toward the appli it is preferred that the solids content of the coat cator roll so that the fountain and the appli ing material be above 60% solids, and generally cator roll form a coating container, a doctor roll within the range of about 61% to 75% solids. above the applicator roll and at a selected distance The apparatus and process herein disclosed per mits the coating of paper from about four hun 45 therefrom, a roll mounted above the doctor roll and adapted to contact the surface of the doctor dred feet per minute to about two thousand feet per minute without changing the viscosity or roll, and a doctor blade for cleaning the surface other characteristics of the coating material. of the roll that contacts the surface of the doc It is to be understood that changes, modi? tor roll. 8. In a coating apparatus comprising, a back cations, etc., may be made by those skilled in the ing means for supporting a moving web of paper; art without departing from the spirit of the inven resilient surfaced applicator roll for transferring tion as described herein. What is claimed: coating material to paper supported between the 1. In a coating unit including a backing means, backing means and said roll, a fountain having an applicator roll for transferring coating mate 55 an open side directed toward the applicator roll rial to a material to be coated supported by the so that the fountain and the applicator roll form backing means, a fountain having an open side a coating container, a metering roll mounted in directed toward the applicator roll so that the the fountain maintained at a selected distance fountain and the applicator roll form a coating from the applicator roll, a doctor roll above the container, a metering roll mounted in the foun 60 applicator roll and at a selected distance there tain at a selected distance from the applicator from, a roll mounted above the doctor roll for roll, and a doctor roll above the applicator roll contacting the surface of the doctor roll, means at a selected distance therefrom. for cleaning the surface of the roll that contacts 2. A coating apparatus including a backing roll, the doctor roll surface, and means for returning an applicator roll for transferring coating mate 65 the coating material to the fountain removed rial to a moving web supported by the backing from the roll contacting the surface of the doctor roll, a fountain having on open side directed to roll. 9. A coating apparatus comprising, a backing ward the applicator roll so that the fountain and applicator roll form a coating container, a doc roll, an applicator roll for applying coating ma tor roll above the applicator roll at a selected 70 terial to a traveling web of paper, a fountain hav distance therefrom, and a roll mounted above the ing an open side directed toward the applicator doctor roll and contacting the surface of the roll so that the fountain and the applicator roll form a coating container, a metering roll mounted doctor roll. 3. A coating unit including a backing cylin in the fountain at a selected distance from the drical member, a fountain, an applicator roll re 75 applicator roll, a doctor roll mounted above the 2,406,057 applicator roll and at a selected distance there from; a roll for, cleaning the surface, of they doc tor rolLand means for controlling the pressure between the applicator roll, the doctor roll and the roll for cleaning the doctor roll surface. 10. In combination with a nest of coated paper driers, a backing means, a fountain having an 8 tance from the applicator roll, a hard surfaced doctor roll mounted above the’ applicator roll and’ at a selected distance therefrom, and a re silient surfaced roll mounted above the doctor roll for cleaning the surface of the doctor roll. 12. A coating unit including a backing roll, an applicator roll for transferring coating material to a web of paper and the like supported by the open.’ side, an applicator roll for rotating into and out of the fountain at the open side, a metering backing roll, a fountain having an open side di roll mounted in the, fountain at a selected dis 10 rected toward the applicator roll so that the tance fromrthe applicator roll, a doctor roll fountain and the applicator roll form a coating mounted above the applicator roll and at a se container, a metering roll at a selected distance lected ‘distance therefrom, and means [for clean from the applicator roll for controlling the ing the surface of the doctonroll. , _ A _ amount of coating material carried by the appli 11. In a coating apparatus comprising, a back 15 cator roll from the coating container, and a ing means, an applicator roll having a surface with resilientrpropertiesa fountain having, an openside directedtoward the applicator roll ‘so that the applicator roll and the fountain form a coating container, a hard ‘surfaced ‘metering 20 roll mounted in the fountain at a selected dis doctor roll at a selected distance from the appli cator roll for smoothing the coating on the said applicator roll. WILLIAM H. BARRETT.’ BERNARD K. ASDELL.