US3630729A - Electrophotographic multicolor copy process employing solubilizable dyes - Google Patents

Electrophotographic multicolor copy process employing solubilizable dyes Download PDF

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Publication number
US3630729A
US3630729A US836415A US3630729DA US3630729A US 3630729 A US3630729 A US 3630729A US 836415 A US836415 A US 836415A US 3630729D A US3630729D A US 3630729DA US 3630729 A US3630729 A US 3630729A
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United States
Prior art keywords
photoconductive
component
coating
receptor
dye
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Expired - Lifetime
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US836415A
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English (en)
Inventor
Frederick O Bach
Leo N Chapin
Robert Freed
Thomas J Cernoch
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AB Dick Co
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AB Dick Co
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G9/00—Developers
    • G03G9/08—Developers with toner particles
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording-members for original recording by exposure, e.g. to light, to heat or to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/09—Sensitisors or activators, e.g. dyestuffs
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording-members for original recording by exposure, e.g. to light, to heat or to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/12—Recording members for multicolour processes
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G9/00—Developers
    • G03G9/08—Developers with toner particles
    • G03G9/09—Colouring agents for toner particles
    • G03G9/0906—Organic dyes

Definitions

  • This invention relates to an electrophoto'graphic process, materials and elements for the production of true color copies from multicolor originals with but a single exposure to light.
  • FIG. 1 is a top plan view of a portion of a receptor embodying the coatings applied in accordance with a preferred practice of this invention
  • FIG. 2 is an enlarged sectional view through a portion of the receptor sheet shown in FIG. 1;
  • FIG. 3 is a schematic sectional view similar to that of FIG. 2, illustrating the conditions existing in response to exposure to a multicolor original;
  • FIG. 4 is a schematic sectional view of the exposed receptor of FIG. 3 after treatment with a developer composition
  • FIG. 5 is a schematic diagram showing the transfer of the multicolor image from the receptor to a copy sheet
  • FIG. 6 is a top plan view of the multicolor copy produced from the exposed receptor of FIG. 5.
  • the concepts of this invention are practiced with a receptor provided with a number of photoconductive coatings each of which is formulated to contain I) an organic insulating binder, such as an organosilicon resin, a butadiene-styrene copolymer resin, a modified alkyd resin and the like; (2) a photoconductor such as photoconductive zinc oxide or other photoconductive material such as described in the Middleton et al. US. Pat. No.
  • an organic insulating binder such as an organosilicon resin, a butadiene-styrene copolymer resin, a modified alkyd resin and the like
  • a photoconductor such as photoconductive zinc oxide or other photoconductive material such as described in the Middleton et al. US. Pat. No.
  • a sensitizing component such as a sensitizing wavelength within the photo conductor to light of a selected wavelength within the visible light spectrum while reflecting wavelengths outside said range, with each coating containing a sensitizing ingredient which sensitizes the photoconductive coating to a different portion of the visible light range, whereby the total of the coating provides sensitivity which covers the entire visible light range
  • a soluble dye component in each coating having a color transfer value corresponding to the subtractive color for which the particular coating is sensitized, as represented by a color produced by the combination of ranges of light reflected by the sensitized photoconductor of the particular coating composition and in which the concepts of this invention include the use of a developer which is formulated with a component, normally identified as a toner, which comprises a solid material in finely divided form which, in response to activation as by heat, solvent, vapors or the like, functions as a solvent for the soluble dye component (4) of the photoconductive coating to effect transfer of the dye color from the portions
  • the visible spectrum may be subdivided into contiguous segments, preferably three or more segments, such as subdivision of the visible light spectrum, assumed to be included within the range of 400-700 nm. into segments of about 400-500, 500-600 and 600-700 nm.
  • the sensitizng component for one coating would then be selected to sensitize the photoconductor to light of within the range of 400-500 nm. (blue sensitivity) and to reflect light within the range of 500-700 nm.
  • This particular effect can be achieved by the use of a dyestuff corresponding to the yellow layer in the well known photographic color processes based upon the subtractive tripack, such as Auramine 0 (Cl. 4!,000
  • the soluble dye component formulated into the described coating composition is selected of a dyestuff having a yellow color or a color which represents the combination of the reflected light range of 500-700 nm.
  • Another or second coating is formulated with a sensitizing component effective to sensitize the photoconductor in the light range of 500-600 nm. (green sensitivity), while reflecting light within the range of 400-500 nm. and 600-700 nm.
  • a sensitizing component effective to sensitize the photoconductor in the light range of 500-600 nm. (green sensitivity), while reflecting light within the range of 400-500 nm. and 600-700 nm.
  • This can be achieved by the use of a magenta coating, when reference is made to the subtractive tripack system, such as by formulating the coating composition to contain acridine red (C.I. 45,000
  • the soluble dye component formulated into the described coating would be selected of a dyestuff having preferably a blue-red color corresponding to the combination of the reflected light within the range of 400-500 and 600-700 nm.
  • the third coating would be formulated to contain a sensitizing component which sensitizes the photoconductor to absorbed light within the range of 600-700 nm. (red sensitivity), while reflecting light within the range of 400-600 nm. This can be achieved by a cyan coat, such as with Patent Blue (CI. 42045).
  • the soluble dye component in the third coating would be selected of a dyestuff giving a blue-green color corresponding to the range of reflected light or the combination of colors within the range of 400-600 nm.
  • the described coating compositions can be formulated to contain the resinous binder in an amount within the range of 10-40 parts by weight of resinous binder per parts by weight of zinc oxide, and preferably in an amount within the range of 15-30 parts by weight of resinous binder per I00 parts by weight of zinc oxide.
  • the sensitizing component or dyestuff is formulated in the coating composition in an amount within the range of 0.001 to 5.0 part by weight per 100 parts by weight zinc oxide and preferably within the range of 0.01 to 2.5 part by weight per 100 parts by weight of zinc oxide, the amount depending somewhat upon the sensitizing dye, such as 0.13 percent by weight of magenta color, as in the form of acridine red having a spectral response in the range of 495-620 A., 0.06 percent of the cyan color, as represented by Patent Blue having a spectral response in the range of 600-700 A., and 1.2 percent by weight of the yellow color as represented by Auramine 0 having a spectral response within the range of 405-500 A.
  • sensitizer per 100 parts by weight zinc oxide
  • the soluble dye component can be formulated into each coating in an amount within the range of 05-200 parts by weight per 100 parts by weight of zinc oxide and preferably in an amount within the range of l-5 parts by weight per I00 parts by weight of zinc oxide.
  • sensitizer and soluble dye components to the percent by weight of the photoconductive coatings formulated of photoconductive zinc oxide or a photoconductor other than zinc oxide, but in which the percentage is adjusted by the weight ratio of zinc oxide to said other photo conductive material in the coating.
  • the soluble dye component is preferably formulated in the respective coating compositions as a dispersed dye but it will be understood that the soluble dye component can be incorporated in other states.
  • the coatings are produced from compositions containing the described components in combination with a diluent which is a solvent for the resinous binder and application may be made to the substrate in coating weights, when formulated of a zinc oxide photoconductor, within the range of 8-40 pounds per 3,000 square feet of surface area, and preferably within the range of 15-30 pounds per 3,000 square feet of surface area.
  • the separate coating compositions are applied or other wise imprinted on the surface of the substrate in various patterns.
  • the essential requirement is that the face of the coated substrate define a final pattern of separate, small light responsive areas of each coating interspersed one with another substantially uniformly over the surface of the substrate in closely spaced relation.
  • the separate coating compositions can be applied in a pattern of dots, circles, beads, spheres, squares, lines or the like configurations. Since it is not essential that the separate light responsive areas be arranged coplanar, it is preferred to apply the coating compositions either in the form of lines which crisscross one another over the surface of the substrate or more preferably to apply one coating composition as a continuous coating over the surface of the substrate and to apply the remaining coatings as lines which crisscross over the underlying base coat as islands or dots of various configuration which overlie the base coat.
  • the receptor sheet will be formed of a substrate having portions coated with only one layer of the first coating, other portions with two layers formed of the first and second coats and first and third coats; and still other portions formed of three layers of the first, second and third coating, etc.
  • the first coating 20, which may be the magenta coat of example is applied either by a roller coater, by a metering rod,
  • the yellow coating composition of example 2 is applied, as by silk screen in a coating weight of about 15 pounds per 3,000 square feet of surface area in a pattern of closely spaced parallel lines 22 which extend crosswise over the surface of the first coating 20.
  • the described coatings can be applied in various other sequences such as a first coating of the yellow coat of example 2 followed by second and third coatings of example I and 3, or a first coat of example 3 and second and third coatings of examples 3 and 2 or 2 and 3, etc.
  • the cyan coating composition of example 3 is also applied, as by silk screen in a coating weight of about 15 pounds per 3,000 square feet of surface area in a pattern of closely parallel lines 24 which extend lengthwise over the first and second coatings to provide crossover points 26 having three thicknesses of coating with the third coating 24 uppermost on the face of the substrate or paper base sheet.
  • the final coated sheet constitutes a receptor suitable for use in the practice of this invention with separate sections 28 having a single-coating thickness of the magenta coating, separate sections 30 having a double-coating thickness formed of a lowermost magenta coating 20 and an uppermost yellow coating 22 and a lowermost magenta coating 20 and an uppermost cyan coating 24 and still other sections 32 having a triple coating thickness formed of a lowermost magenta coating 20, an intermediate yellow coating 22 and an uppermost cyan coating 24.
  • the exposed face of the receptor presents separate sections of each of the coatings in substantially uniformly dispersed relation over the face of the receptor sheet.
  • the receptor sheet is charged in the usual manner, now well known to the electrostatic copy art, as by subjecting the face of the receptor to a corona spray as it is exposed to corona discharge from wires operating at a potential of about 6,000 to 8,000 volts.
  • the charged wires which extend across the face of the receptor, are either transported over the face of the receptor or the receptor is displaced beneath the wires.
  • the electrostatic charge is deposited over the entire receptor covered by one or more of the photoconductive coatings.
  • the charged receptor is next exposed to the multicolor original.
  • Such portions of the original which are blue in color, for example, will cause discharge of the corresponding areas on the face of the receptor formed of the yellow coating which is sensitized to blue, leaving the charges in the corresponding areas on the exposed face sections of the magenta and cyan coatings for subsequent development.
  • the portions of the original which are green in color cause discharge of the corresponding areas 28 on the face of the receptor of the magenta coating, which are sensitized to green, leaving the charge 34 on the corresponding areas on the face sections 32 of cyan and sections 30 of the yellow coating for subsequent development, as depicted in H6. 3.
  • the portions of the original which have the color red will cause discharge in the corresponding areas of the receptor of the cyan sections'32 on the exposed face of the receptor sheet which are sensitized to red, leaving the charges on the corresponding areas in the exposed faces sections of magenta and yellow for subsequent development.
  • the exposed receptor sheet is developed in the conventional manner either with a dry powder developer or with a liquid developer, but in which the conventional particles of toner in the dry powder developer suspended in the liquid developer are substituted by finely divided particles of a compound which, when activated as by heat or solvent, vapor and the like, becomes a solvent for the dispersed dye in the coating.
  • EXAMPLE 4 5.0 grams toner (Antipyrine) 400 ml. liquid carrier (lsopar G-Humble Oil Co.) 5 grams charge director (Fuel Oil Additive No. 2--DuPont EXAMPLE 5 5.0 grams toner (l-allyl-Z-thiourea) 400 ml. liquid carrier 5 grams charge director
  • the Isopar G used as the liquid carrier in the above example is parafi'mic hydrocarbon liquid having 1l.8 percent C hydrocarbons, 56.2 percent C hydrocarbons, 31.7 percent C hydrocarbons, less than 0.3 aromatics and less than 0.1 olefins, a boiling point within the range of 3l8-350 F., a flash point of 104 F.
  • the Fuel Oil Additive No. 2 is a solution of a methacrylate copolymer having an average molecular weight of 50,000. Again, other conventional charge directors can be employed.
  • the antipyrine of example 4 and the l-allyl-Z-thiourea of example 5 are merely representative of suitable toner particles which may be used for development of the latent electrostatic image of the charged sections that remain after exposure.
  • suitable toner particles may be used which meet the requirements:
  • toner particles can be employed in various concentrations in the developer composition, such as within the range of 2-20 percent by weight, and preferably 3-10 percent by weight, in a dry powder developer and within the range of 02-20 percent by weight and preferably 2-10 percent by weight in a liquid developer.
  • the toner concentration can range up to 100 percent by weight toner in the developer.
  • toner particles 36 will be retained the portions of the face of the receptor which remain charged to define the latent electrostatic image after exposure while the discharge sections on the face of the receptor will remain substantially free of the toner particles, as depicted in FIG. 41.
  • the developer receptor sheet is pressed into surface contact with a copy sheet 40, as by passage of the composite assembly between compression rollers heated to a temperature above the melting point temperature for the toner, such as at a temperature above lll-l 13 C. which is the melting point for antipyrine, or above a temperature of 77-78 C. which is the melting point for l-allyl-2-thiourea, and preferably by heating the toner particles to a temperature which exceeds their melting point by a slight amount preferably about 5-l0 lF.
  • the toner particles are reduced to a fluidized state to enable solution of the dispersed dye in the underlying portions of the photoconductive coating in the face of the receptor for transfer of the corresponding dye color, as by diffusion, from the receptor to the copy sheet 40.
  • the copy produced by the combination of colors transferred from the developed receptor sheet will correspond to the colored original and that the developed receptor can function in a manner of a spirit master to produce multiple copies of the multicolor original, as by the successive passage of copy sheets into pressure contact with the developed receptor until the soluble dyestuff in the toned face segments are exhausted.
  • An electrophotographic process for the production of multicolor copies of a multicolor original comprising the steps of applying an electrostatic charge onto the face of a receptor formed of a substrate having on its face interspersed sections of two or more photoconductive coatings each of which contains a photoconductive component, a sensitizer for the photoconductive component and a solubilizable dye, in which the sensitizer in one coating sensitizes the photoconductor to a particular segment of the visible light range for absorption of light within said range and reflection of light outside said range, and in which the solubilizable dye corresponds with the color of the reflected light, and in which separate coatings are provided with sensitizing components designed to cover substantially the entire visible light range, whereby and electrostatic charge is retained by each of said photoconductive coatings, exposing the charge receptor to the original whereby the sections on the face of the receptor are discharged in response to exposure to color in corresponding areas of the original to which the particular sections have been sensitized, leaving the charge on the sections from which the light has been reflected, developing the exposed receptor with
  • interspersed sections of photoconductive coatings comprise interspersed sections of three separate coating systems sensitized to the additive primary colors of red, green, blue, respectively.
  • the toner is an organic compound selected from the group consisting of antipyrene and 1-allyl-2-thiourea 10.
  • activation of the toner comprises the step of heating the coated receptor to a temperature above the melting point temperature of the toner while the copy sheet is in pressure contact with the face of the receptor.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Photoreceptors In Electrophotography (AREA)
  • Developing Agents For Electrophotography (AREA)
  • Liquid Developers In Electrophotography (AREA)
  • Color Electrophotography (AREA)
US836415A 1969-06-25 1969-06-25 Electrophotographic multicolor copy process employing solubilizable dyes Expired - Lifetime US3630729A (en)

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US83641569A 1969-06-25 1969-06-25

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US (1) US3630729A (de)
JP (1) JPS4926587B1 (de)
BE (1) BE752540A (de)
CA (1) CA920859A (de)
CH (1) CH532804A (de)
DE (1) DE2031534C3 (de)
FR (1) FR2051193A5 (de)
GB (1) GB1311114A (de)
NL (1) NL7009333A (de)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3772053A (en) * 1972-09-22 1973-11-13 Eastman Kodak Co Electrographic formation of dye images
US3915703A (en) * 1972-08-07 1975-10-28 Hitachi Ltd Photoconductive composition and element employing a sensitizer and a light filtering substance
US4063946A (en) * 1973-01-22 1977-12-20 Rank Xerox Ltd. Electrophotographic color reproduction process employing photoconductive material with dual light fatigue properties
US4077802A (en) * 1970-12-01 1978-03-07 A. B. Dick Company Single color electrophotographic copy process
US4121932A (en) * 1974-09-28 1978-10-24 Matsushita Electric Industrial Co., Ltd. Electrophotographic process involving dye transfer imagewise
US4390614A (en) * 1981-03-16 1983-06-28 Richard M. Peck Color facsimile printing device comprising photosensitive ink in pores
US4420552A (en) * 1981-03-16 1983-12-13 Richard M. Peck Method of producing printed images with a color facsimile printing device
US4481528A (en) * 1980-10-08 1984-11-06 Peck Richard M Multicolor image printing device and method
US4911999A (en) * 1988-12-13 1990-03-27 E. I. Du Pont De Nemours And Company Electrostatic master containing thiourea or thioamide electrostatic decay additive for high speed xeroprinting

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56151937U (de) * 1980-04-15 1981-11-13
JPS588983A (ja) * 1981-07-07 1983-01-19 株式会社チノ− 球形黒体炉

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2962374A (en) * 1956-05-01 1960-11-29 Haloid Xerox Inc Color xerography
US3212887A (en) * 1961-04-07 1965-10-19 Minnesota Mining & Mfg Laterally disposed coterminously adjacent multicolor area containing graphic reproduction receptor and electrophotographic process of using same
US3329590A (en) * 1961-04-07 1967-07-04 Minnesota Mining & Mfg Electrolytic development of a subtractive color-forming photoconductive member
US3458310A (en) * 1964-01-11 1969-07-29 Kalle Ag Electrophotographic color printing
US3549359A (en) * 1966-04-26 1970-12-22 Fuji Photo Film Co Ltd Color electrophotography employing dye transfer from a dye-containing photosensitive layer to an image receiving sheet

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2962374A (en) * 1956-05-01 1960-11-29 Haloid Xerox Inc Color xerography
US3212887A (en) * 1961-04-07 1965-10-19 Minnesota Mining & Mfg Laterally disposed coterminously adjacent multicolor area containing graphic reproduction receptor and electrophotographic process of using same
US3329590A (en) * 1961-04-07 1967-07-04 Minnesota Mining & Mfg Electrolytic development of a subtractive color-forming photoconductive member
US3458310A (en) * 1964-01-11 1969-07-29 Kalle Ag Electrophotographic color printing
US3549359A (en) * 1966-04-26 1970-12-22 Fuji Photo Film Co Ltd Color electrophotography employing dye transfer from a dye-containing photosensitive layer to an image receiving sheet

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4077802A (en) * 1970-12-01 1978-03-07 A. B. Dick Company Single color electrophotographic copy process
US3915703A (en) * 1972-08-07 1975-10-28 Hitachi Ltd Photoconductive composition and element employing a sensitizer and a light filtering substance
US3772053A (en) * 1972-09-22 1973-11-13 Eastman Kodak Co Electrographic formation of dye images
US4063946A (en) * 1973-01-22 1977-12-20 Rank Xerox Ltd. Electrophotographic color reproduction process employing photoconductive material with dual light fatigue properties
US4121932A (en) * 1974-09-28 1978-10-24 Matsushita Electric Industrial Co., Ltd. Electrophotographic process involving dye transfer imagewise
US4481528A (en) * 1980-10-08 1984-11-06 Peck Richard M Multicolor image printing device and method
US4390614A (en) * 1981-03-16 1983-06-28 Richard M. Peck Color facsimile printing device comprising photosensitive ink in pores
US4420552A (en) * 1981-03-16 1983-12-13 Richard M. Peck Method of producing printed images with a color facsimile printing device
US4911999A (en) * 1988-12-13 1990-03-27 E. I. Du Pont De Nemours And Company Electrostatic master containing thiourea or thioamide electrostatic decay additive for high speed xeroprinting

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Publication number Publication date
DE2031534A1 (de) 1971-01-28
CA920859A (en) 1973-02-13
DE2031534B2 (de) 1974-10-24
CH532804A (de) 1973-01-15
GB1311114A (en) 1973-03-21
NL7009333A (de) 1970-12-29
FR2051193A5 (de) 1971-04-02
BE752540A (fr) 1970-12-01
DE2031534C3 (de) 1975-06-05
JPS4926587B1 (de) 1974-07-10

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