US3172826A - Photoconductography employing organic onium cation - Google Patents

Photoconductography employing organic onium cation Download PDF

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Publication number
US3172826A
US3172826A US2293160A US3172826A US 3172826 A US3172826 A US 3172826A US 2293160 A US2293160 A US 2293160A US 3172826 A US3172826 A US 3172826A
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United States
Prior art keywords
photoconductor
water
areas
solution
sheet
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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
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English (en)
Inventor
Vsevolod Tulagin
Robert Fleming Coles
Richard Allan Miller
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.)
3M Co
Original Assignee
Minnesota Mining and Manufacturing 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
Application filed by Minnesota Mining and Manufacturing Co filed Critical Minnesota Mining and Manufacturing Co
Priority to US2293160 priority Critical patent/US3172826A/en
Priority to ES0266308A priority patent/ES266308A1/es
Priority to DK156661AA priority patent/DK105632C/da
Priority to CH452061A priority patent/CH415301A/de
Priority to NL263728A priority patent/NL263728A/nl
Priority to GB14060/61A priority patent/GB990971A/en
Priority to BE602732A priority patent/BE602732A/fr
Priority to FR859408A priority patent/FR1290455A/fr
Application granted granted Critical
Publication of US3172826A publication Critical patent/US3172826A/en
Priority to NL696916060A priority patent/NL139210B/nl
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
    • 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
    • G03G5/05—Organic bonding materials; Methods for coating a substrate with a photoconductive layer; Inert supplements for use in photoconductive layers
    • G03G5/0525—Coating methods
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G13/00—Electrographic processes using a charge pattern
    • G03G13/01—Electrographic processes using a charge pattern for multicoloured copies
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G13/00—Electrographic processes using a charge pattern
    • G03G13/26—Electrographic processes using a charge pattern for the production of printing plates for non-xerographic printing processes
    • G03G13/28—Planographic printing plates
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G17/00—Electrographic processes using patterns other than charge patterns, e.g. an electric conductivity pattern; Processes involving a migration, e.g. photoelectrophoresis, photoelectrosolography; Processes involving a selective transfer, e.g. electrophoto-adhesive processes; Apparatus essentially involving a single such process
    • G03G17/02—Electrographic processes using patterns other than charge patterns, e.g. an electric conductivity pattern; Processes involving a migration, e.g. photoelectrophoresis, photoelectrosolography; Processes involving a selective transfer, e.g. electrophoto-adhesive processes; Apparatus essentially involving a single such process with electrolytic development
    • 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

Definitions

  • This invention relates to new and useful permanent reproductions and their method of preparation by selectively depositing and irreversibly bonding a water insoluble organic compound on the surface of a photoconductor.
  • An object of this invention is to disclose a method for selectively depositing water insoluble organic compounds on the surface of a photoconductor, thereby producing reproductions in a fast and efficient manner.
  • Another object of this invention is to disclose a process for preparing colored reproductions by electrophotography. These colored reproductions are prepared by successively applying subtractive primary colors to the surface of the photoconductor. The methods of making colored reproductions from subtractive primaries is described in J. S. Friedmans A History of Color Photography, American Photographic Publishing Company, Boston, Mass. (1944).
  • the positively charged onium ion is attracted to the conductive areas of the cathode-photoconductor and is electrolytically de composed to deposit a water insoluble substance on the exposed surface of the photoconductor.
  • dye-sensitized indicates that the photoconductor has been treated with an organic dyestutf so that radiant energy is absorbed by the dye on the surface of the photoconductor and the energy is transferredto the photoconductor thereby making the photoconductor conductive.
  • This process may be employed in various ways to prepare permanent reproductions.
  • the preferred method is to deposit a colored water insoluble compound and in this manner the photoconductor is colored directly. If the water insoluble substance is colorless it may be colored in a subsequent step to produce a negative image or it may serve as a protective coating-for the portions of photoconductor covered and the unprotected areas are then colored or modified chemically in some other manner, such as by dyeing or etching away the photoconductor with an acid or solvent; Likewise, the surface wetting characteristics of selected areas of the photo- 3,172,825, Patented Mar. 9, 1965 conductive sheet can be modified to attract or repel water or oil.
  • the water insoluble compound may also be derived from an emulsifying agent which upon decomposition releases dispersed water insoluble pigments which are then deposited on the selected areas of the photoconductor.
  • the chemical decomposition effected electrolytically in the practice of this invention relates to onium compounds because they impart water solubility to many water insoluble compounds and because they are positively charged compounds.
  • onium compounds encompasses quaternary nitrogen compounds, sulfonium, phosphonium, arsonium, oxonium and similar compounds that have a positively charged electronegative atom.
  • the decomposition products of these compounds which are deposited on the photoconductor surface are water insoluble compounds, even in the presence of an acid or base.
  • FIGURE 1 is a perspective view of developing apparatus useful in the practice of this invention and FIGURE 2 is a cross-sectional view of FIGURE 1 along section line 22.
  • Developer tray 19 is composed of a base plate 12, which also serves as an eloctrode, top clamping frame member 14, and an intermedate open frame member 16 forming upstanding walls around the base plate periphery.
  • Frame member 14 and base plate 12 have cooperating, releasable clamping means 18, which draw these members toward one another when engaged to render the tray 10 water tight.
  • the open frame member 1 is composed of a non-conductor such as polyethylene, polytetrafluoroethylene or polytrifiuorochloroethylene and is provided with a ledge 20 for supporting electrode 22 such that an electrical current passing to electrode 22 from the base plateelectrode 12 passes through a photoconductor sheet 24 which is interposed between the open frame member 16 and the base plate 12.
  • This photoconductor sheet 24 is composed of an electrically conductive carrier 26 which is placed in intimate contact with the base plate 12 and photoconductor particles 28.
  • a solution 32 is placed in the developer tray 10, electrode 22 is connected to the positive terminal of the direct current power source 34' and'the base plate 12 is attached to the negative terminal of the power supply 34.
  • the electrical current passes through solution 32 and the photoconductivc areas of the photoconductive sheet 24 resulting in image deposits 36* on the cathode-photoconductive surface.
  • FIGURE 2 In order to graphically show the photo conductor particles 23 and the image deposit 30, they have been represented in FIGURE 2 in exaggerated size.
  • the negative electrode from a direct current power supply 34 is attachedto the metal base plate thereby making electrical contact with the conductive backing of the photoconductor sheet 24.
  • the photoconductor sheet 24 in the developing tray 10 is exposed to light in selected areas such as by focusing and projecting a photographic negative on the photoconductor sheet 24 through a projector.
  • the electrode 22 is placed on the ledge 26 and connected to the positive terminal of the direct current power supply/34.
  • the solution 32 is added to the tray.
  • the electrical current is turned on so as to effect the electrolytic development.
  • the solution is poured oil and the photoconductor sheet is thoroughly washed with water. After suitable dark adaptation additional images may be put on the photoconductor sheet by repeating the above procedure.
  • An especially useful method for dark adaptation of the photoconductor sheet is to placeit in contact with water heated to at least 100 F. whichmay be accomplished simultaneously with the washing by employing the hot water as the Wash water.
  • Color reproductions may be obtained by carrying out the above procedure three times with monochromatic light.
  • a color negative is placed in a projector equipped with a photofiood lamp and a red filter is interposed between the photofiood lamp and the photoconductor sheet, preferably between the color negative and the photoflood lamp thereby exposing the photoconductor sheet selectively to red light.
  • a cyan image is then developed on the photoconductor using a cyan dye.
  • the photoconductive paper is then washed with warm water (heated to at least 100 F.) and dried with a stream of air.
  • the developing tray is then returned to the enlarger and a green filter is interposed between the light source and the photoconductor sheet.
  • the light intensity of the projected image, time of exposure which may be from 0.1 second to sixty seconds, and period of electrolytic development which may be from 1 to 36 seconds at a voltage of from 5 to 150 volts are varied in accordance with the quality of the image required or desired and the relative effectiveness of the photoconductor surface.
  • photoconductor sheet backings prepared by vapor deposition of a metal, such as aluminum, on a paper or plastic backing are especially useful.
  • a metal such as aluminum
  • Polyethylene terephthalate films (5 mil) are preferred.
  • Example 1 This example shows the preparation of chromogenic onium ions and the electrotlytic decomposition of the onium ions to directly form a colored image on a zinc oxide photoconductor sheet prepared as described above.
  • a 5% aqueous solution of the solid was employed to prepare a negative yellow print on the zinc oxide photoconductor sheet in accordance with the procedure outlined above.
  • This filter cake was'dissolved in 75% aqueous pyridine ml.). Several drops of hydrochloric acid were added and powdered iron (15 g'.) was added slowly td the hot solution. After heating for one hour and filtering hot, the filtrate was diluted to one liter with water. The resulting solid was collected by filtration and then redissolved in glacial acetic acid (75 nil). This solution was filtered to remove residual insolubles and the filtrate was poured into water (200 mi The solid product was collected, washed with water and methanol, and dried. This solid product (3 g.) was added to ml. chloro' acetyl chloride. The resulting warm solution was treated with anhydrous potassium acetate (2 g.). Excess chloroacetyl chloride was removed at reduced pressure and the residue treated with ice and water. The resulting gum was triturated with dilute bicarbonate solution to yield a red-brown solid which was collected by filtration and washed with water.
  • the red-brown solid was added to molten N,N,N,N'- tetramethylthiourea g.) and the melt heated for onehalf hour on a steam bath.
  • the resulting deep red solution was poured into acetone (400 ml.) to yield a reddish gum which was solidified by repeated trituration with fresh acetone.
  • a 1% aqueous solution of the solidifled product deposited a positive magenta image on zinc oxide photoconductor sheet as described above.
  • the addition of a small amount of acetic acid to the solution resulted in production of a negative magenta image on the photoconductor using the same process.
  • the purple powder was added to molten N,N,N,N'- tetramethylthiourea (20 g.). After heating the melt on a steam bath for 20 minutes it was poured into acetone (500 ml.) and the resulting solid collected and dried. This material was dissolved in water to make a 1% solution, and filtered. The solution was then selectively deposited as a reddish purple negative image on the zinc oxide photoconductor as described above.
  • p-Aminoacetanilide was reacted with Z-hydroxy-S- naphthoic acid in hot toluene with the aid of phosphorus trichloride.
  • the acetyl group was then hydrolyzed by warming with dilute aqueous alcoholic potassium hydroxide for several hours.
  • the product was coupled in pyridine and dimethylformamide solution with the diazo from 2-methyl-4-chloroani1ine.
  • the resulting azo dye was chloroacetylated with excess chloroacetyl chloride in hot toluene.
  • the resulting reaction product was reacted with N,N,N',N'-tetrarnethylthiourea by adding the dye to a melt of the tetramethylthiourea at 150 C. and stirring for four minutes.
  • the melt was cooled, digested with water and the solution recooled.
  • the precipitated tetramethylthiourea was removed by filtration and the magenta colored solution of the thiuronium salt, the structure of which is shown above, was used to obtain a negative image on zinc oxide by the above-described method.
  • Example 2 This example demonstrates various applications of this invention made possible by the decomposition of water soluble, colorless onium ions and the deposition of a colorless image of a water insoluble decomposition product.
  • N-tetradecyl p chloromethylbenzenesulfonamide (1.0 g.) and N,N,N,N-tetramethylthiourea (0.4 g.) were mixed and heated at 110 C. for several minutes. Heptane was added, the mixture was heated, stirred and centrifuged. The gelatinous solid (1.2 g.) was then washed with petroleum ether and dried.
  • a solution of this thiuronium salt in water was employed to deposit a colorless negative image on a zinc oxide photoconductor sheet in areas rendered conductive in accordance with the above outlined procedure.
  • the areas of the sheet so coated were water repellent and were preferentially dyed to produce a colored negative image with an aqueous solution of Basolan Chrome Brilliant Red BBM, a product of Badische Anilinund Sodafabrik AG., Ludwigshafen, Germany.
  • the unexposed areas which were not coated by the colorless image were treated as follows: (1) A dilute solution of hydrochloric acid and acetic acid was employed to remove the zinc oxide from these unprotected areas. The zinc oxide areas covered by the deposited compound were not aifected.
  • Example 3 This example shows the deposition of pigments and dyes dispersed in a solution containing onium ions.
  • a black image was obtained when the suspension contained carbon black.
  • Example 4 A sheet of zinc oxide electrophotographic paper was exposed in all areas to white light, and then colored with Alcian Blue 8 GN by electrolytic deposition on the surface of a zinc oxide photoconductor sheet to produce a blue-green sheet. This sheet was dark state adapted by contacting it' with hot water followed by drying. The sheet was then exposed "to a photographic image, contacted with a suspension of titanium dioxide in a dilute aqueous solution of the th'iuroniur'n salt from N-tetradecyl-p-chloromethylbenzenesulfonamide and N,N,N,N'- tetramethylthiourea. Concurrently with the decomposition of the thiouronium salt, the titanium dioxide was selectively deposited in the light-struck areas of the sheet. The remaining blue-green areas then gave the appearance of a positive image.
  • a method for selectively depositing and irreversibly bonding a water insoluble substance on the surface of a dye-sensitized photoconductor bonded to an electrically conductive carrier which comprises exposing said photoconductor to a light source in the selected areas thereby rendering the exposed areas electrically conductive, contacting the conductive areas with a water solution containing a water soluble organic onium cation which de- 1 1 composes electrolytically to form a water insoluble compound, passing an electrical current through the water solution and the conductive areas of the pbotoconductorcathode thereby attracting said cation to the conductive areas of the photoconductor, electrolytically decomposing said cation to produce a water insoluble organic compound which is deposited and irreversibly bonded on the exposed areas of the photoconduc'tor, and coloring the water insoluble compound deposit with a colored substance.
  • a method for selectively depositing and irreversibly bonding a water insoluble substance on the surface of a dye-sensitized photoconductor bonded to an electrically conductive carrier which comprises exposing said photoconductor to a light source in the selected areas thereby rendering the exposed areas electrically conductive, contacting the conductive areas with a water solution containing a water soluble organic onium cation which decomposes electrolytically to form a water insoluble compound, passing an electrical current through the water solution and the conductive areas of the photoconductorcathode thereby attracting said cation to the conductive areas of the photoconductor, electrolytically decomposing said cation to produce a water insoluble organic compound which is deposited and irreversibly bonded on the exposed areas of the photoconductor, and coloring the areas of the photoconductor not covered by said water insoluble compound with a colored substance.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Molecular Biology (AREA)
  • Coloring (AREA)
  • Photoreceptors In Electrophotography (AREA)
US2293160 1960-04-18 1960-04-18 Photoconductography employing organic onium cation Expired - Lifetime US3172826A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US2293160 US3172826A (en) 1960-04-18 1960-04-18 Photoconductography employing organic onium cation
ES0266308A ES266308A1 (es) 1960-04-18 1961-04-05 Un metodo de depositar selectivamente y unir irreversiblemente una sustancia sobre un fotoconductor
CH452061A CH415301A (de) 1960-04-18 1961-04-17 Verfahren zur Herstellung von Reproduktionen
DK156661AA DK105632C (da) 1960-04-18 1961-04-17 Fremgangsmåde til elektrolytisk fremstilling af permanente reproduktioner.
NL263728A NL263728A (nl) 1960-04-18 1961-04-18 Werkwijze en inrichting voor het vervaardigen van permanente afdrukken
GB14060/61A GB990971A (en) 1960-04-18 1961-04-18 Permanent reproductions and their preparation
BE602732A BE602732A (fr) 1960-04-18 1961-04-18 Reproductions permanentes et leur préparation
FR859408A FR1290455A (fr) 1960-04-18 1961-04-18 Procédé de fabrication de reproductions photographiques permanentes et en couleurs
NL696916060A NL139210B (nl) 1960-04-18 1969-10-24 Elektrofotografische plaat.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US2293160 US3172826A (en) 1960-04-18 1960-04-18 Photoconductography employing organic onium cation

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US3172826A true US3172826A (en) 1965-03-09

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US2293160 Expired - Lifetime US3172826A (en) 1960-04-18 1960-04-18 Photoconductography employing organic onium cation

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US (1) US3172826A (fr)
BE (1) BE602732A (fr)
CH (1) CH415301A (fr)
DK (1) DK105632C (fr)
ES (1) ES266308A1 (fr)
FR (1) FR1290455A (fr)
GB (1) GB990971A (fr)
NL (1) NL263728A (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436321A (en) * 1966-09-13 1969-04-01 Minnesota Mining & Mfg Developer compositions and their use in electrolytic electrophotography
US4002475A (en) * 1975-05-05 1977-01-11 Eastman Kodak Company Photoconductive process for making electrographic masters
US6194108B1 (en) * 1996-10-17 2001-02-27 Fuji Xerox Co., Ltd. Image forming method and image forming device using same

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2297691A (en) * 1939-04-04 1942-10-06 Chester F Carlson Electrophotography
US2854386A (en) * 1955-02-07 1958-09-30 Aladdin Ind Inc Method of photographically printing conductive metallic patterns
US2857271A (en) * 1954-09-28 1958-10-21 Rca Corp Electrostatic printing process for producing photographic transparencies
US2862816A (en) * 1954-03-26 1958-12-02 Rca Corp Method of and means for reducing triboelectric forces in electrophotography
US2874101A (en) * 1952-09-17 1959-02-17 Farnsworth Res Corp Method of making double-sided mosaic
US2955035A (en) * 1956-01-03 1960-10-04 Haloid Xerox Inc Raised xerographic images
US3010883A (en) * 1956-03-30 1961-11-28 Minnesota Mining & Mfg Electrolytic electrophotography

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2297691A (en) * 1939-04-04 1942-10-06 Chester F Carlson Electrophotography
US2874101A (en) * 1952-09-17 1959-02-17 Farnsworth Res Corp Method of making double-sided mosaic
US2862816A (en) * 1954-03-26 1958-12-02 Rca Corp Method of and means for reducing triboelectric forces in electrophotography
US2857271A (en) * 1954-09-28 1958-10-21 Rca Corp Electrostatic printing process for producing photographic transparencies
US2854386A (en) * 1955-02-07 1958-09-30 Aladdin Ind Inc Method of photographically printing conductive metallic patterns
US2955035A (en) * 1956-01-03 1960-10-04 Haloid Xerox Inc Raised xerographic images
US3010883A (en) * 1956-03-30 1961-11-28 Minnesota Mining & Mfg Electrolytic electrophotography

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436321A (en) * 1966-09-13 1969-04-01 Minnesota Mining & Mfg Developer compositions and their use in electrolytic electrophotography
US4002475A (en) * 1975-05-05 1977-01-11 Eastman Kodak Company Photoconductive process for making electrographic masters
US6194108B1 (en) * 1996-10-17 2001-02-27 Fuji Xerox Co., Ltd. Image forming method and image forming device using same

Also Published As

Publication number Publication date
ES266308A1 (es) 1961-12-01
CH415301A (de) 1966-06-15
FR1290455A (fr) 1962-04-13
BE602732A (fr) 1961-10-18
NL263728A (nl) 1964-06-10
GB990971A (en) 1965-05-05
DK105632C (da) 1966-10-17

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