|Publication number||US3206323 A|
|Publication date||Sep 14, 1965|
|Filing date||Jun 12, 1962|
|Priority date||Jun 12, 1962|
|Publication number||US 3206323 A, US 3206323A, US-A-3206323, US3206323 A, US3206323A|
|Inventors||Frank D Miller, John J Wheeler|
|Original Assignee||Eastman Kodak Co|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (6), Referenced by (61), Classifications (28)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Sept. 14, 1965 F. D. MILLER ETAL COATING HIGH VISCOSITY LIQUIDS Filed June 12, 1962 INVENTORS BY MK A/TRTMRNEYS Eomlnw E M3310 2250583 E52 op wuSwn m FRANK 0. MILLER JOHN J WHEELER E953 mm; $6035 23 United States Patent 3,206,323 COATING HIGH VlSCOSlTY LIQUIDS Frank D. Miller and John J. Wheeler, Rochester, N.Y., assignors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey Filed June 12, 1962, Ser. No. 201,869 3 Claims. (Cl. 117-34) This invention relates to a method for coating fluid compositions, and more particularly to a method for coating viscous fluids at high speeds.
Previous attempts to coat high viscosity fluids upon nonpermeable web support-s at high speeds such as at least 200 feet per minute have generally been unsatisfactory, primarily because air bubbles are entrapped under the coatings. The formation of these bubbles can be suppressed by the coating technique which involves supplying a ribbon of fluid coating from a stationary coating device, contacting the ribbon with a moving web support and subjecting the side of the ribbon adjacent the web support to a low-er pressure (pressure differential) than the opposite side of the ribbon, as described in U.S. Patent 2,681,294, issued on June 15, 1954 to Beguin. This coating technique allows good coatings at moderate speeds, but as the coating speeds are increased to 300 feet per minute and higher, correspondingly higher pressure differentials must be maintained to prevent bubble formation. However, the use of high pressure differentials introduces other problems in obtaining good coatings. For example, at high pressure differentials, it is difficult to hold the web support on the coating roll. In addition, it is diflicult to obtain coatings free of longitudinal streaks. Therefore, it appears desirable to provide a method for coating viscous fluids onto web supports at high speeds which overcomes the difficulties encountered by prior art methods.
One object of our invention is to provide a method of coating viscous fluids onto web supports at high speeds. Another object of our invention is to provide a method of coating viscous fluids onto web supports at high speeds without forming air bubbles in the coating. A further object of our invention is to provide a method of coating viscous fluids onto nonpermeable web supports at high speeds without the use of high differential pressures. Still another object of our invention is to provide a method of coating viscous fluids onto nonpermeable web supports at speeds above 200 feet per minute. A further object of our invention is to provide a method of coating viscous photographic emulsions onto nonpermeable support-s, such as baryta coated paper or cellulose ester film base, at speeds above 200 feet per minute.
Other objects of our invention will appear herein.
We have found that viscous fluids may be coated onto a web support at high speeds by the coating method which comprises forming a ribbon containing a distinct layer of the viscous fluid and a distinct layer of a low viscosity fluid coating composition, contacting the side of the ribbon composed of the layer of low viscosity fluid coating composition with a web support having an electrostatic potential different than that of said ribbon, simultaneously supplying the ribbon and the web support while moving the support across and in contact with the ribbon, and subjecting that side of the ribbon having the layer of low viscosity fluid coating composition to a lower pressure than the other side of the ribbon.
The drawing represents a diagrammatic view illustrating an apparatus which may be used to practice the coating method of the invention. The web support 1 is passed around a grounded metal roll 2 and under a device 3 for imparting a charge to web support 1. The web support 1 is then passed around guide roll 4 and thence around 3,205,323 Patented Sept. 14, 1965 grounded metal coating roll 5, .and past a stationary coating device 6 having inlet means 7 for a low viscosity liquid coating composition and an inlet means 8 to supply the viscous fluid coating composition. The low viscosity fluid coating 7 and the viscous fluid coating 8 pass through orifices L and L, respectively, and are simultaneously coated onto the web support 1 in distinct layer relationship as indicated at 10 and 11. A vacuum chamber 12 is provided to subject the ribbon of coating fluids to a lower pressure on the side of the ribbon composed of the layer of low viscosity fluid coating composition than the opposite side of the ribbon, and is provided with an evacuation pipe 13 attached to evacuating means not shown.
The utilization of a flow of ionized air to render a web or other sheet material electrically neutral or'to distribute an electrical charge on the surface thereof is well known in the art, and apparatus for generating such flows of ionizedair are disclosed in US. Patents 1,678,869, which was granted to M. Morrison on July 31, 1938, and 2,497,604, which was granted to P. Henry et al. on February 14, 1950.
The method of simultaneously applying multiple coatings is described in US. Patent 2,761,791, issued September'4, 1956, to T. A. Russell. Apparatus for applying simultaneously a plurality of coatings is described in US. Patents 2,761,417, issued September 4, 1956 to T. A. Russell et al., and 2,761,418, issued September 4, 1956 to T. A. Russell.
The method of coating fluids onto a support which involves employing a lower pressure on the side of the ribbon of coating composition adjacent to the web support than the pressure on the opposite side of the ribbon is described in U.S. Patent 2,681,294, issued June 15, 1954 to Beguin.
Our invention will be further illustrated by the following examples which demonstrate the necessity for incorporating all the aspects of applicants combination to achieve high speed coating of viscous fluids.
Example 1 A high viscosity 30% gelatin solution, having a viscosity of 3,000 cps., was coated at 110 F. onto cellulose ester film base at the rate of .5 to .18 lb. per square feet using a pressure differential of 4 inches of water pressure. The maximum speed of coating which could be achieved without the formation of undesirable bubbles was 213 feet per minute.
Example 2 A gelatin solution having a viscosity of 2,500 cps. was coated onto cellulose ester film base at the rate of .5 to .18 lb. per 100 square feet. A pressure differential of 26 inches of water pressure was required to achieve a good coating at a coating speed of 300 feet per minute. At a coating speed of 500 feet per minute, a pressure differential of 49 inches of water pressure failed to prevent the formation of bubbles in the coating.
Example 3 The procedure of Example 1 was followed except that a low viscosity (15 cps.) gelatin coating was simultaneously coated with the viscous fluid of Example 1 so that the low viscosity coating was adjacent the film base, in accordance with the method described by Russell US. Patent 2,761,791, at the rate of .04 lb. per 100 square feet. The maximum speed which could be achieved without the formation of bubbles was 280 feet per minute.
Example 4 A high viscosity 30% gelatin solution having a viscosity of 3,000 cps., was coated at F. on to cellulose ester film base to which had been imparted an electrostatic charge of 950 field volts. Bubbles were formed in the coating at a coating speed of 213 feet per minute.
Example A high viscosity gelatin solution, having a viscosity of 3,000 cps., was simultaneously coated (in accordance with the method described by Russell U.S. Patent 2,761,791) With a low viscosity (15 cps.) gelatin solution at 110 F. onto a cellulose ester film base to which had been imparted an electrostatic charge of 950 volts as measured against a grounded metal roll. The low viscosity gelatin solution was applied adjacent the film base at the rate of .04 lb. per 100 square feet with the high viscosity gelatin solution thereover at the rate of .5 to .18 lb. per 100 square feet. A pressure differential of 4 inches of water pressure was maintained in accordance with the method described by Beguin U.S. Patent 2,681,294. No bubbles were formed in coatings obtained at the coating rate of 500 feet per minute. The coatings were highly satisfactory in all respects.
The above examples demonstrate that a highly unexpected increased rate of coating high viscosity fluids on a web support is achieved when (1) a low viscosity fluid coating composition is simultaneously coated with the high viscosity coating composition, applying the layer of low viscosity fluid coating adjacent the support, by forming a ribbon containing a layer of the high viscosity fluid and the low viscosity fluid in bridging relationship between a stationary coating device and the Web support, (2) subjecting that side of the ribbon having the layer of low viscosity composition to a lower pressure than the opposite side of the ribbon, and (3) maintaining an electrostatic potential difference between the ribbon and the web support prior to the point of contact thereof. The examples further show that a drastic limitation in coating speed occurs when any one of the three requirements are omitted from the inventive method.
7 Our invention is generally applicable to coating viscous fluids at high speed onto web supports, particularly nonpermeable web supports such as a cellulose ester film base or baryta coated paper. The invention is especially well suitedto the coating of fluid gelatinous coating compositions, such as gelatino-silver-halide photographic emulsions and antih-alation pelloid backings, such as carbon black dispersed in gelatin. The low viscosity fluid may advantageously be a gelatinous fluid coating composition.
Other suitable low viscosity fluid coating compositions may be employed.
The viscosity of the fluids which may be coated in accordance with our invention range from 1,000 to 60,000 cps. Especially good results are achieved with fluid coating compositions having a viscosity in the range of 2,000 to 4,000 cps.
In some instances, it may be desirable to provide web supports having various coatings over the high viscosity fluid coating. Such coatings may be coated simultaneously With the high viscosity coating or subsequently applied either before or after drying the first high viscosity coating. These coatings may range from low to high viscosity.
The low viscosity coating compositions which are employed in the invention should have a viscosity of about 5 to cps., with particularly good results being achieved with coatings of 5 to 20 cps.
The differential pressure which may be employed in carrying out the invention may be from 1" to 10" of water pressure and preferably is about 4 inches of water pressure.
While we have found it convenient to obtain the required potential diflference between the web support and the coating fluid by the apparatus shown herein, there are many other means of achieving this potential difference which will be readily apparent to those skilled in the art.
The important consideration is that there be a different electrostatic potential between the web support and the coating composition prior to the point of contact. This total difference in potential should be between 800 and 10,000 volts, and preferably is about 950 volts.
The invention has been described in detail With particular reference to preferred embodiments thereof but it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinabove and as defined in the appended claims.
1. The method of coating a fluid having a viscosity of 1,000 to 60,000 cps. onto a nonpermeable web support at speeds in excess of about 300 ft./min. which comprises:
(1) forming a ribbon containing both a layer of the fluid coating and an outer layer of a fluid coating having a viscosity of 5 to 50 ops,
(2) subjecting that side of the ribbon composed of the layer of fluid having a viscosity of 5 to 50 cps. to a lower pressure than the other side of the ribbon, the diiference in pressure being from about 1 to about 10 inches of Water pressure,
(3) contacting the side of the ribbon composed of the fluid having a viscosity of 5 to 50 cps. with a nonpermeable web support having an electrostatic potential different than that of said ribbon, said electrostatic potential difierence being from 800 to 10,000 volts, and
(4) simultaneously supplying the ribbon and moving the web support across and in contact with the ribbon.
2; The method of claim 1 wherein the fluid coating having a viscosity of 1,000 to 60,000 cps. is a gelatino silver halide emulsion, the fluid coating having a viscosity of 5 to 50 cps. is a gelatinous fluid and the web support is selected from the group consisting of baryta coated paper and cellulose ester film base.
3. The method of coating a gelatino silver halide emulsion having a viscosity of 2,000 to 4,000 cps. at speeds in excess of about 300 ft./-min. onto a web support selected from the group consisting of baryta coated paper and cellulose ester film base which comprises:
(1) forming a ribbon containing both a layer of the gelatino silver halide emulsion and an outer layer of a gelatinous fluid having a viscosity of 5 to 25 cps,
(2) subjecting the side of the ribbon composed of the layer of gelatinous fluid to a lower pressure than the other side of the ribbon, the difference in pressure being about 4 inches of water pressure,
(3) contacting the side of the ribbon composed of the gelatinous fluid with said web support, said web support having an electrostatic potential different than that of said ribbon, said electrostatic potential difference being about 950 volts, and
(4) simultaneously supplying the ribbon and moving the web support across and in contact with the ribbon.
References Cited by the Examiner UNITED STATES PATENTS 1,678,869 7/28 Morrison 317-2 2,497,604 2/50 Henry. et a1 28-22 2,681,294 6/54 Beguin 117-34 2,761,791 9/56 Russell 117-34 2,952,559 9/60 Nadeau 117-34 3,082,144 3/63 Haley 117-34 X WILLIAM D. MARTIN, Primary Examiner. MURRAY KATZ, Examiner.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1678869 *||Dec 1, 1922||Jul 31, 1928||Montford Morrison||Static dissipator|
|US2497604 *||Jul 15, 1947||Feb 14, 1950||British Cotton Ind Res Assoc||Method of and means for eliminating electrostatic charges in industrial processes|
|US2681294 *||Aug 23, 1951||Jun 15, 1954||Eastman Kodak Co||Method of coating strip material|
|US2761791 *||Feb 23, 1955||Sep 4, 1956||Eastman Kodak Co||Method of multiple coating|
|US2952559 *||Nov 1, 1956||Sep 13, 1960||Eastman Kodak Co||Method of coating a liquid photographic emulsion on the surface of a support|
|US3082144 *||Nov 8, 1957||Mar 19, 1963||Du Pont||Extrusion coating under reduced pressure|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3335026 *||Jul 16, 1963||Aug 8, 1967||Gevaert Photo Prod Nv||Method for coating liquid compositions employing electrostatic field|
|US3501330 *||Oct 22, 1965||Mar 17, 1970||Agfa Gevaert Nv||Manufacture of electrophotographic materials|
|US3502494 *||Nov 4, 1966||Mar 24, 1970||Fuji Photo Film Co Ltd||Process and apparatus for continuous fluid coating of a traveling web|
|US3503370 *||May 2, 1967||Mar 31, 1970||Fuji Photo Film Co Ltd||Coating apparatus|
|US3508947 *||Jun 3, 1968||Apr 28, 1970||Eastman Kodak Co||Method for simultaneously applying a plurality of coated layers by forming a stable multilayer free-falling vertical curtain|
|US3522080 *||Jul 18, 1968||Jul 28, 1970||Bayer Ag||Process for hardening the surfaces of synthetic materials|
|US3526528 *||Oct 27, 1966||Sep 1, 1970||Fuji Photo Film Co Ltd||Multiple doctor coating process and apparatus|
|US3539426 *||Jan 13, 1967||Nov 10, 1970||Fuji Photo Film Co Ltd||Multiple layer coating method|
|US3547682 *||Mar 15, 1968||Dec 15, 1970||Hercules Inc||Composite polyolefin extrusion coating of substrates|
|US3584600 *||Feb 13, 1970||Jun 15, 1971||Fuji Photo Film Co Ltd||Multiple doctor blade coating apparatus|
|US3638604 *||Feb 10, 1969||Feb 1, 1972||Agfa Gevaert Ag||Apparatus for coating strip-form substrates|
|US3640752 *||Jun 24, 1969||Feb 8, 1972||Fuji Photo Film Co Ltd||Coating method|
|US3641978 *||Jan 7, 1969||Feb 15, 1972||Porvair Ltd||Coating apparatus|
|US3645773 *||Feb 10, 1969||Feb 29, 1972||Agfa Gevaert Ag||Process for coating substrates in strip-form with photographic emulsion|
|US3663292 *||Feb 10, 1969||May 16, 1972||Agfa Gevaert Ag||Process for coating strip-form substrates|
|US3756195 *||Aug 5, 1971||Sep 4, 1973||Eastman Kodak Co||Apparatus for coating a continuous web|
|US3869304 *||Nov 20, 1972||Mar 4, 1975||Uniroyal Inc||Fabric coating by extrusion die-calendering apparatus and method|
|US3916043 *||Nov 15, 1971||Oct 28, 1975||Eastman Kodak Co||Method of coating a spliced web|
|US3918977 *||Aug 13, 1973||Nov 11, 1975||Gte Sylvania Inc||Method for coating metallic strips|
|US4001024 *||Mar 22, 1976||Jan 4, 1977||Eastman Kodak Company||Method of multi-layer coating|
|US4466378 *||Jun 28, 1982||Aug 21, 1984||Dynamelt Limited||Coating applicator head|
|US4476165 *||Jun 7, 1982||Oct 9, 1984||Acumeter Laboratories, Inc.||Method of and apparatus for multi-layer viscous fluid deposition such as for the application of adhesives and the like|
|US4537801 *||May 23, 1983||Aug 27, 1985||Fuji Photo Film Co., Ltd.||Coating method and apparatus|
|US4798163 *||May 5, 1988||Jan 17, 1989||Meltex Verbindungs-Technik Gmbh||Slit nozzle|
|US4835021 *||May 6, 1988||May 30, 1989||Eastman Kodak Company||Coating process|
|US4863765 *||Feb 24, 1988||Sep 5, 1989||Fuji Photo Film Co., Ltd.||Method of multi-layer coating|
|US4948654 *||Feb 27, 1989||Aug 14, 1990||Eastman Kodak Company||Sheet material useful in forming protective and decorative coatings|
|US5186754 *||Apr 6, 1990||Feb 16, 1993||Konica Corporation||Coater|
|US5456944 *||Jul 29, 1993||Oct 10, 1995||Eastman Kodak Company||Magnetic dispersion coating method having high shear regions|
|US5582645 *||Jun 7, 1995||Dec 10, 1996||Eastman Kodak Company||Magnetic dispersion coating apparatus having high shear regions|
|US5607726 *||Oct 17, 1994||Mar 4, 1997||E. I. Du Pont De Nemours And Company||Process for the preparation of composite coatings with variable thickness|
|US5728430 *||Jun 7, 1995||Mar 17, 1998||Avery Dennison Corporation||Method for multilayer coating using pressure gradient regulation|
|US5962075 *||Mar 15, 1996||Oct 5, 1999||Avery Dennison||Method of multilayer die coating using viscosity adjustment techniques|
|US6368675||Apr 6, 2000||Apr 9, 2002||3M Innovative Properties Company||Electrostatically assisted coating method and apparatus with focused electrode field|
|US6475572||Apr 6, 2000||Nov 5, 2002||3M Innovative Properties Company||Electrostatically assisted coating method with focused web-borne charges|
|US6666918||Jul 26, 2002||Dec 23, 2003||3M Innovative Properties Company||Electrostatically assisted coating apparatus with focused web charge field|
|US6716286||Jan 22, 2002||Apr 6, 2004||3M Innovative Properties Company||Electrostatically assisted coating method and apparatus with focused electrode field|
|US6776948||Jul 26, 2001||Aug 17, 2004||Ultrafab, Inc.||Method and apparatus for applying coatings of molten thermoplastic material over closed pore elastomer foam substrates|
|US6824828||Aug 8, 2002||Nov 30, 2004||Avery Dennison Corporation||Method for forming multilayer release liners|
|US7247206 *||Mar 17, 2004||Jul 24, 2007||Voith Paper Patent, Gmbh||Medium application device|
|US7255769 *||Dec 19, 2002||Aug 14, 2007||Fujifilm Manufacturing Europe B.V.||Method for splicing and coating webs as well as a web obtained with such methods|
|US7523524 *||Aug 27, 2003||Apr 28, 2009||Alps Electric Co., Ltd.||Ultrasonic cleaner and wet treatment nozzle comprising the same|
|US7718251||Mar 9, 2007||May 18, 2010||Amesbury Group, Inc.||Systems and methods for manufacturing reinforced weatherstrip|
|US7942495||Jan 5, 2009||May 17, 2011||3M Innovative Properties Company||Method of and apparatus for ink jet printing using an electrostatic field|
|US8893644 *||Sep 21, 2007||Nov 25, 2014||Aisin Kako Kabushiki Kaisha||Wide slit nozzle for discharging a damping material in an overlapping manner with fixed dimensions|
|US9358716||Jan 20, 2010||Jun 7, 2016||Amesbury Group, Inc.||Systems and methods for manufacturing reinforced weatherstrip|
|US20030152740 *||Dec 19, 2002||Aug 14, 2003||Fuji Photo Film B.V.||Method for splicing and coating webs as well as a web obtained with such methods|
|US20040035451 *||Aug 27, 2003||Feb 26, 2004||Kenichi Mitsumori||Ultrasonic cleaner and wet treatment nozzle comprising the same|
|US20040208997 *||May 11, 2004||Oct 21, 2004||Arvidson Richard T||Method and apparatus for applying coatings of molten thermoplastic material over closed pore elastomer foam substrates|
|US20040216663 *||Mar 17, 2004||Nov 4, 2004||Voith Paper Patent Gmbh||Medium application device|
|US20050074549 *||Nov 18, 2004||Apr 7, 2005||Avery Dennison Corporation||Method for forming multilayer release liners and liners formed thereby|
|US20050100677 *||Nov 18, 2004||May 12, 2005||Avery Dennison Corporation||Method for forming multilayer release liners and liners formed thereby|
|US20080083843 *||Sep 21, 2007||Apr 10, 2008||Aisin Kako Kabushiki Kaisha||Wide split nozzle and coating method by wide slit nozzle|
|US20090174755 *||Jan 5, 2009||Jul 9, 2009||3M Innovative Properties Company||Method of and apparatus for ink jet printing using an electrostatic field|
|DE2712055A1 *||Mar 18, 1977||Oct 6, 1977||Eastman Kodak Co||Verfahren zum herstellen photographischen materials|
|EP0096453A2 *||Mar 4, 1983||Dec 21, 1983||Acumeter Laboratories Inc.||Method of and apparatus for multi-layer viscous fluid deposition such as for the application of adhesives and the like|
|EP0096453A3 *||Mar 4, 1983||Jun 26, 1985||Acumeter Laboratories Inc.||Method of and apparatus for multi-layer viscous fluid deposition such as for the application of adhesives and the like|
|EP0110074A2 *||Oct 12, 1983||Jun 13, 1984||Agfa-Gevaert AG||Multiple coating process for moving webs|
|EP0110074A3 *||Oct 12, 1983||Nov 13, 1985||Agfa-Gevaert Aktiengesellschaft||Multiple coating process for moving webs|
|EP0999249A2 *||Nov 2, 1999||May 10, 2000||Singulus Technologies AG||Process for avoiding the inclusion of bubbles during the joining by adhesives of optical data carrier substrates|
|EP2903065A4 *||Aug 27, 2013||Dec 23, 2015||Nissan Motor||Coating device|
|U.S. Classification||430/531, 427/482, 118/621, 118/411, 118/50, 118/50.1|
|International Classification||B05C5/02, B29C47/06, G03C1/74, B29C47/88, B05D1/26, B05C9/06|
|Cooperative Classification||B05C5/0254, B05C9/06, G03C1/74, B29C47/8845, B29C47/145, B29C47/0021, B29C47/065, B29C47/0019, B05D1/26|
|European Classification||B05D1/26, B29C47/14B, B29C47/06P, B05C5/02F, B29C47/88C4B, B05C9/06, G03C1/74|