US2959492A - Backing paper for roll photographic film - Google Patents

Backing paper for roll photographic film Download PDF

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Publication number
US2959492A
US2959492A US793177A US79317759A US2959492A US 2959492 A US2959492 A US 2959492A US 793177 A US793177 A US 793177A US 79317759 A US79317759 A US 79317759A US 2959492 A US2959492 A US 2959492A
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US
United States
Prior art keywords
paper
coating
backing paper
carbon black
film
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US793177A
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English (en)
Inventor
Ernest L Baxter
Salo Martin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Eastman Kodak Co
Original Assignee
Eastman Kodak Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to BE587456D priority Critical patent/BE587456A/xx
Application filed by Eastman Kodak Co filed Critical Eastman Kodak Co
Priority to US793177A priority patent/US2959492A/en
Priority to DEP1267A priority patent/DE1267545B/de
Priority to FR818193A priority patent/FR1247789A/fr
Priority to GB5235/60A priority patent/GB950484A/en
Application granted granted Critical
Publication of US2959492A publication Critical patent/US2959492A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • 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
    • G03C3/00—Packages of films for inserting into cameras, e.g. roll-films, film-packs; Wrapping materials for light-sensitive plates, films or papers, e.g. materials characterised by the use of special dyes, printing inks, adhesives
    • G03C3/02—Photographic roll-films with paper strips
    • 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
    • D21H19/00—Coated paper; Coating material
    • D21H19/36—Coatings with pigments
    • D21H19/44—Coatings with pigments characterised by the other ingredients, e.g. the binder or dispersing agent
    • D21H19/54—Starch
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/24—Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24802—Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
    • Y10T428/24851—Intermediate layer is discontinuous or differential
    • Y10T428/24868—Translucent outer layer
    • Y10T428/24876—Intermediate layer contains particulate material [e.g., pigment, etc.]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/26—Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
    • Y10T428/263—Coating layer not in excess of 5 mils thick or equivalent

Definitions

  • This invention relates to backing paper for roll photographic film, and more particularly relates to an improvement in the backing paper, described in Patent 2,751,309 of June 19, 1956, which has protective light-colored and opaquing coatings thereon and is characterized by having an overall thickness appreciably less than conventional backing papers, and is superior in opaqueness to duplex backing paper.
  • a photographic roll film cartridge generally comprises a flanged spool upon which is wound a long strip of backing paper to which, before winding, has been attached on one side thereof a strip of light sensitive photographic film.
  • the ends of the backing paper are positioned to extend beyond the ends of the film and constitute light protective leader and trailer strips for film which is interwound with the backing paper so that it separates adjacent convolutions of the film.
  • backing paper conventionally employed for roll film consists of a duplex paper with one side being black and the other side being colored with v a characteristic identifying color.
  • the duplex paper may be made by means of a Fourdriner paper machine and a cylinder paper machine. The two sheets are brought togethers wet under the first press and thus form a composite sheet of duplex backing paper.
  • the film is attached to the black side of the duplex backing paper, the side of the backing paper opposite that contacting the film being differently colored and carrying various printed symbols such as the number of exposed areas, warning marks, and advertising matter over which is coated a protective layer intended to protect the sensitive emulsion from the paper and ink employed in printing when the film and paper are interwound in close contact. It has been the practice to depend entirely on the duplex paper to prevent transmission of light which would act on the film in the roll in loading and unloading the camera or through the camera window.
  • the black side of the backing paper comprises a layer either of carbon black in a vinylidene chloride-acrylonitrile copolymer or of carbon black in a styrene-butadiene copolymer.
  • Backing paper with a black layer made of carbon black in a styrene-butadiene copolymer is preferred, however, an unforeseen disadvantage was experienced with its use. Blocking of the styrene-butadiene to the zein coating on the opposite side occurs in the coating operation. Blocking also occurs between the styrene-butadiene coating and 2,959,492 Patented Nov. 8,1960
  • An object, therefore, of the present invention is to provide an improved backing paper structure in which the advantages of the single sheet backing paper of Patent 2,751,309 are retained and the above-described static and I sticking tendencies are eliminated.
  • the opposite side .of the paper is coated with a plurality of lighter colored coatings. Printing may be placed on the lighter colored side of the backing paper and, if so printed, the printed side maybe given a transparent protective overcoating to protect the film emulsion from the printing inks.
  • the various coatings may be applied in proper sequence by a rotogravurc process or by other suitable coating processes such as described hereinafter. The coatings may be suitably dried between applications.
  • the paper preferably employed as the base of the backing paper structure is a 14 pound per 1000 sq. ft. paper made of a purified fiber or of unpurified fiber such as unbleached natural color kraft paper which is conditioned to 4-12% moisture content and su'percalendered to a thickness of 0.0025 to 0.0030 inch.
  • the compositions of each of the black coatings and each of the light-colored coatings are further described hereinafter.
  • Example I Percent I Styrene-butadiene copolymer (50-70% styrene) (48% solids in aqueous colloidal dispersion) Carbon black Sodiun salt of partially desulfonated lignin sulfonic aci NaOH Water (48% solids in aqueous colloidal dispersion) 19.8
  • Carbon black 16.0 Water 63.3 Sodium salt of partially desulfonated lignin sulfonic acid 0.80 NaOH 0.08
  • the selected resin copolymers are added with stirring to a 30-40% aqueous carbon dispersion.
  • the carbon dispersion is made by adding the carbon to water containing as a dispersing agent the sodium salt of the partially desulfonated lignin sulfonic acid and caustic soda is added to control the pH within the range of :1.
  • Example II The black coating of Example II is preferred.
  • ethyl cellulose is Dow Ethocel Type 10. It has a relatively low viscosity and a high solubility in ethanol. The resulting ethyl cellulose-carbon coating gives complete freedom from static and sticking.
  • YELLOW COATINGS The following three compositions may be employed for coating the light-colored side of the backing paper.
  • Example IV Pounds Zein 20 Medium chrome yellow 10 Light orange (chrome) 5 Titanium dioxide Isopropyl alcohol 64 Water 16 Staybelite (hydrogenated rosin)* 1.2
  • a pale, medium hard, thermoplastic resin made from hydrogenated wood rosin; acid number 162; softening point 76 C. density 1.045 at 20 C.
  • Example V Percent Styrene-butadiene copolymer (50 to 70% styrene)
  • the titanium dioxide pigment is finely divided; medium chrome yellow is a finely divided metal chromate pigment; light orange is a finely divided metal chromate pigment.
  • Zein is employed as the binder in the yellow coating of Example IV and the protective overcoating, since it will not fog or desensitize the photographic emulsion of the film.
  • a suitable rotogravure process for applying these coatings to the paper base of the backing paper is described in U.S. Patent 2,218,249 of October 15, 1940.
  • the various applications are made continuously and each coating is dried before the next is applied.
  • the coating is applied to the paper by the intaglio roll which is rotatably mounted in a pan containing the coating solution.
  • the surface of the intaglio roll is embossed, providing a plurality of very minute cups which carry the solution, the excess solution being removed from the intaglio roll by a doctor blade.
  • the solution in these various cups is then transferred or applied uniformly to the strip by pressing the strip firmly against the cups by means of a rubber pressure roll over which the strip is fed.
  • Each of these deposits after being placed on the paper, is merged into a continuous layer by means of a smoothing bar to provide a uniform coating over the entire paper surface.
  • Each coating is preferably dried in heated air having a relative humidity of 6% at F. before applying a second coating.
  • the various coatings described herein may also be applied to our backing paper base by the roll and air knife method generally described in Patent 1,980,923 of November 13, 1934.
  • the selected black coating is applied first to one side of the single sheet backing paper and spread by the air knife. This black coating is dried at -200" F. by being passed through a heated drying chamber. In some instances a plurality of black coatings may be spread onto the black side of the backing paper by alternate coating and drying steps.
  • Suitable ink compositions for printing indicia by rotogravure processes on the backing paper are disclosed in Patent Re. 21,268 of November 21, 1939. These inks comprise suitable coloring materials in a prolamine binder such as zein. Other suitable printing inks for such backing papers are disclosed in Patent 2,262,987 of November 18, 1941.
  • Figs. 1 to 3 represent a greatly enlarged cross-section of backing paper made in accordance with various forms of the present invention
  • Fig. 4 shows the novel backing paper of Fig. 1 and photographic film wound on the roll with the film and backing paper separated at one end for purpose of illustrating their relative positions in the roll.
  • a cross-section of a strip of bleached kraft paper is shown at 10 having on the lower surface thereof a coating 11 of a layer of carbon black in styrene-butadiene copolymer coated from the composition of Example 1.
  • Layer 11 is overcoated with a layer 12 of carbon black in ethyl cellulose which is coated thereon from the composition of Example III.
  • the printed indicia is shown at 14 overcoated with a transparent protective zein coating 15.
  • a transparent zein protective coating is described in Patent 2,262,987 of November 18, 1941 and is also employed in layers 25 and 35 of Figs. 2 and 3.
  • a cross-section of a strip of bleached kraft paper is shown at 20 having on its lower surface a coating 21 of a layer of carbon black in the styrene-butadiene copolymer coated from the composition of Example II.
  • Layer 21 is overcoated with a layer 22 of carbon black in ethyl cellulose which is coated thereon from the composition of Example III.
  • a yellow coating 23 comprising chrome yellow and titanium dioxide in a styrene-butadiene binder. This was coated from the composition described in Example V.
  • the printed indicia is shown at 24 overcoated with a transparent zein coating 25.
  • a cross-section of a strip of bleached kraft paper is shown at 30 having on its lower surface a coating 31 of a layer of carbon black in the styrene-butadiene copolymer coated from the composition of Example II.
  • Layer 31 is overcoated with a layer 32 of carbon black in ethyl cellulose which is coated thereon from the composition of Example HI.
  • the upper surface of the paper 30 there is a yellow coating 33 comprising medium chrome yellow and titanium dioxide in a vinylidene chloride-acrylonitrile copolymer. This was coated from the composition described in Example VI.
  • the printed indicia is shown at 34 overcoated with a transparent zein coating 35.
  • the backing paper structure described in connection with Fig. 1 is the preferred form of the present invention.
  • the backing paper structure shown in any of the Figs. 1 to 3 gives a product that fulfills all the advantages herein, at an economical cost and results in a non-blocking, non-dust producing backing paper when stored under conditions of high humidities and temperatures or when wound through a camera.
  • a film cartridge 40 is shown partly open in which the backing paper of the present invention is employed.
  • This drawing shows the relation of the backing paper surfaces 15 and 12 of Fig. 1 in respect to film 43 when assembled on the spool 40.
  • the emulsion side of the film is shown at 41 and the base side at 42.
  • Preferred range of total composition Compositions percent Vinylidene chloride-acrylonitrile copolymer of styrene-butadiene copolymer to 25 Black pigment 1 to 20 White pigment 15 to 45 Yellow pigment -1. 15 to 45 Water 50 to 70
  • Other useful pigments are, for example, Hausa Yellow, Fast Pigment Yellow and any carbon black of suitable dispersion.
  • pigments which are inert to photographic emulsions may be employed.
  • any choice of pigments of suitable size for this invention is limited only by the requirement that they be without detrimental effect on the photographic film.
  • THICKNESS OF COATING Black coating composition is applied in two coatings to give a total of 12 lbs. of solution per 1000 sq. foot for satisfactory opacity.
  • Light pigment composition is applied in the amount of 5 lbs. per 1000 sq. foot to give satisfactory uniformity of color.
  • the ethyl cellulose-carbon black coating is applied in .18 lb. per 1000 sq. foot.
  • Any other type of paper may be employed if it has good strength at least comparable to the present duplex paper.
  • a rag paper for example, is suitable but, of course, more expensive than kraft paper.
  • the average tear strength of a suitable paper should be at least 50 gms. as determined by the Elmendorf tear test. This tear test is described in Paper Trade Journal for June 18, 1942 as Tappi Standard T414M40.
  • kraft paper is particularly suited for employment in my invention
  • certain other types of paper could be employed instead, such as unbleached sulfatepaper colored with a suitable dye such as Stilbene yellow in which a small amount of filler such as TiO is added to give body and density or opacity to the paper.
  • These papers comprising the base of the backing paper are of a weight that can be supercalendered to a thinness that the paper itself plus the coatings thereon does not exceed an average maximum thickness of 0.0040 inch. a 15-pound per M sq. ft. paper has been found satisfactory.
  • the opacity of roll film backing paper is tested in the following manner.
  • a sheet of the backing paper under test is placed over a sheet of highly sensitive film, such as Super XX Panchromatic film with the black side of the backing paper in contact with the back of the film, duplicating its position on roll film.
  • An orange-red filter of the type employed in camera back windows is placed over the opposite side of the backing paper and the assembly is placed in a printing frame.
  • the test material is exposed to a light intensity of 5000 foot candles for ten minutes.
  • the film is then processed in the usual way and examined for the presence of specks of developed silver.
  • a satisfactory backing paper should show no visible silver image.
  • our improved backing paper has many advantageous features not possessed by duplex, papers which it may replace.
  • the strength and other physical properties of the paper employed as the base of the backing paper is at least equal to the strength of the thinner duplex papers now available to the trade.
  • the overall thickness can be made as low as 0.0032, up to 0.0045 inch thus permitting extra exposures to be added to present rolls of film without increasing the diameter beyond that of films now in use.
  • the backing paper made in accordance with our invention requires the least amount of coating materials, both black and colored, of any of the methods described or known in the trade. The uniformly lightcolored side gives maximum contrast with the legends printed thereon.
  • photographic backing paper having an overall thickness less than 0.0045 inch consisting of a single sheet of thin kraft paper which is of a thinness which will permit passage of substantial amounts of actinic light, having on one side a light colored pigmented coating consisting essentially of a yellow pigment in a binder selected from the class consisting of vinylidenechlorideacrylonitrile copolymer, styrene-butadiene copolymer and zein, printed indicia on said lighter colored coating, a clear zein protective coating thereover, and on the opposite side an opaque coating consisting of carbon black in a binder of styrene-butadiene copolymer, the improvement which consists in a protective coating over said opaque coating of carbon black in ethyl cellulose.
  • photographic backing paper having an overall thickness less than 0.0045 inch consisting of a single sheet of thin kraft paper which is of a thinness which will permit passage of substantial amounts of actinic light, having on one side a light colored pigmented coating consisting essentially of a yellow pigment in a binder of vinylidene chloride-acrylonitrile copolymer, printed indicia on said lighter colored coating, a clear zein pro-- tective coating thereover, and on the opposite side an opaque coating consisting of carbon black in a binder of styrene-butadiene copolymer, the improvement which consists in a protective coating over said opaque coating of carbon black in ethyl cellulose.
  • photographic backing paper having an overall thickness less than 0.0045 inch consisting of a single sheet of thin kraft paper which is of a thinness which will permit passage of substantial amounts of actinic light, having on one side a light colored pigmented coating consisting essentially of a yellow pigment in a binder of styrene-butadiene copolymer, printed indicia on said lighter colored coating, a clear zein protective coating thereover, and on the opposite side an opaque coating consisting of carbon black in a binder of styrene-butadiene copolymer, the improvement which consists in a protective coating over said opaque coating of carbon black in ethyl cellulose.
  • photographic backing paper having an overall thickness less than 0.0045 inch consisting of a single sheet of thin kraft paper which is of a thinness which will permit passage of substantial amounts of actinic light, having on one side a light colored pigmented coating consisting essentially of a yellow pigment in a binder of zein, printed indicia on said lighter colored coating, a clear zein protective coating thereover, and on the opposite side an opaque coating consisting of carbon black in a binder of styrene-butadiene copolymer, the improvement which consists in a protective coating over said opaque coating of carbon black in ethyl cellulose.

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  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Paper (AREA)
  • Laminated Bodies (AREA)
US793177A 1959-02-13 1959-02-13 Backing paper for roll photographic film Expired - Lifetime US2959492A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
BE587456D BE587456A (en)) 1959-02-13
US793177A US2959492A (en) 1959-02-13 1959-02-13 Backing paper for roll photographic film
DEP1267A DE1267545B (de) 1959-02-13 1959-12-22 Photographisches Schutzpapier
FR818193A FR1247789A (fr) 1959-02-13 1960-02-11 Nouveau papier dorsal pour pellicule photographique
GB5235/60A GB950484A (en) 1959-02-13 1960-02-15 Photographic backing paper

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US793177A US2959492A (en) 1959-02-13 1959-02-13 Backing paper for roll photographic film

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US2959492A true US2959492A (en) 1960-11-08

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US793177A Expired - Lifetime US2959492A (en) 1959-02-13 1959-02-13 Backing paper for roll photographic film

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US (1) US2959492A (en))
BE (1) BE587456A (en))
DE (1) DE1267545B (en))
FR (1) FR1247789A (en))
GB (1) GB950484A (en))

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10228307B2 (en) 2015-09-29 2019-03-12 Biofunctions, Inc. Dissolvable sample collection matrices and methods of using the same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE622442A (en)) * 1961-09-18

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1300056A (en) * 1915-11-06 1919-04-08 Burke & James Inc Paper backing for film-cartridges.
US1915391A (en) * 1932-12-06 1933-06-27 Merle J Stoops Coating mixture
US2227843A (en) * 1939-07-25 1941-01-07 Du Pont Opaque window shade material
US2331715A (en) * 1940-07-20 1943-10-12 Eastman Kodak Co Noncohering thin sheeting
US2340971A (en) * 1939-04-25 1944-02-08 Johnson & Johnson Waterproof tape
US2751309A (en) * 1953-04-10 1956-06-19 Eastman Kodak Co Paper for roll photographic film

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2126350A (en) * 1937-04-03 1938-08-09 Eastman Kodak Co Backing paper for roll coating film
BE544748A (en)) * 1956-01-27

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1300056A (en) * 1915-11-06 1919-04-08 Burke & James Inc Paper backing for film-cartridges.
US1915391A (en) * 1932-12-06 1933-06-27 Merle J Stoops Coating mixture
US2340971A (en) * 1939-04-25 1944-02-08 Johnson & Johnson Waterproof tape
US2227843A (en) * 1939-07-25 1941-01-07 Du Pont Opaque window shade material
US2331715A (en) * 1940-07-20 1943-10-12 Eastman Kodak Co Noncohering thin sheeting
US2751309A (en) * 1953-04-10 1956-06-19 Eastman Kodak Co Paper for roll photographic film

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10228307B2 (en) 2015-09-29 2019-03-12 Biofunctions, Inc. Dissolvable sample collection matrices and methods of using the same

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Publication number Publication date
BE587456A (en))
GB950484A (en) 1964-02-26
DE1267545B (de) 1968-05-02
FR1247789A (fr) 1960-12-02

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