US3128204A - Process of preparing photoconductive layers for electrophotography - Google Patents

Process of preparing photoconductive layers for electrophotography Download PDF

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Publication number
US3128204A
US3128204A US696024A US69602457A US3128204A US 3128204 A US3128204 A US 3128204A US 696024 A US696024 A US 696024A US 69602457 A US69602457 A US 69602457A US 3128204 A US3128204 A US 3128204A
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United States
Prior art keywords
zinc oxide
amount
binding agent
percent
weight
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
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US696024A
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English (en)
Inventor
Schaum Gustav
Haydn Hildegard
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Agfa Gevaert NV
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Agfa AG
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Classifications

    • 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, 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
    • G03G5/0503—Inert supplements
    • G03G5/0507—Inorganic compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
    • 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
    • G03G13/30—Hectographic masters
    • 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, 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
    • G03G5/0503—Inert supplements
    • G03G5/051—Organic non-macromolecular compounds
    • G03G5/0514—Organic non-macromolecular compounds not comprising cyclic groups
    • 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, 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
    • G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
    • G03G5/0662—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic containing metal elements
    • 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, 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
    • G03G5/08—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being inorganic
    • G03G5/087—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being inorganic and being incorporated in an organic bonding material
    • 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
    • G03G9/00—Developers
    • G03G9/08—Developers with toner particles
    • G03G9/09—Colouring agents for toner particles
    • G03G9/0906—Organic dyes
    • G03G9/0912—Indigoid; Diaryl and Triaryl methane; Oxyketone dyes
    • 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
    • G03G9/0926—Colouring agents for toner particles characterised by physical or chemical properties

Definitions

  • photoconductive layers for electrophotography it is known to use certain inorganic or organic photoconductive compounds.
  • examples of such compounds are sulfur and selenium; oxides, sulfides and selenides of zinc, cadmium, mercury, antimony, bismuth, and lead, and also anthracene and anthraquinone.
  • These substances are applied to an electrophotographic plate, especially a plate consisting of metal or another material, for example paper, or to a sheet or foil produced from a film-forming plastic. If necessary, the photoconductive substance can be held dispersed in an elec trically isolating layer-forming binder.
  • Such layers are produced by means of coating solutions in which the binders are either dissolved or dispersed and in which the electroconductive substances are dispersed.
  • Such photoconductive layers are disclosed, for instance, in United States Patents Nos. 2,297,691; 2,357,809; 2,727,807; 2,727,808; 2,735,784; and 2,735,785, and in French Patents Nos. 1,113,933; 1,122,275; 1,125,235; and 1,136,146.
  • the photoconductive layers which are produced from aqueous coating solutions in which the binders are dispersed suffer from the disadvantage that they readily take up moisture from the air owing to the presence of wetting agents and salts, so that the conductivity of the layer in the dark is often raised to such a degree that its image reproduction characteristics are impaired.
  • waterproofing agents can be of various types.
  • Suitable waterproofing agents are the following:
  • paraffin Wax or similar high-molecular hydrocarbons which are preferably applied in the form of their aqueous emulsions; such emulsions are, for instance, disclosed in British Patents Nos. 477,830; 492,742; 469,642, and 627,356.
  • Fatty acids salts of polyvalent metals more especially, fatty acids salts of aluminum, titanium, zirconium, and chromium.
  • the water-repellent or waterproofing agents are preferably applied in the following quantities:
  • the parafiin emulsions when used as emulsions in 3,128,204 Patented Apr. 7, 1964 amounts of 20120%, the compounds quoted under ((7) and (c) in amounts of 15-30%, and the compounds disclosed under (d) in amounts of 0.014% as calculated on the binding agent.
  • film-forming agents for the photoconductive layers in which the photoconductive substances are dispersed there may be used natural or synthetic resins or resinoids preferably such as are soluble in organic solvents, these film-forming agents being used in form of aqueous dispersions as disclosed, for instance, in French Patent No. 1,136,146.
  • the layers produced from said dispersions may be subjected to a final condensation or final polymerization by heat treatment at temperatures of about -150" C. for about 2 to 30 minutes after being dried.
  • Aqueous dispersions of polymeric substances which are soluble in organic solvents such as melamineformaldehyde or urea-formaldehyde resins, xylene-formaldehyde resins, polymers based on vinyl chloride, vinyl idene chloride, vinyl ethers, acrylic esters, methacrylic esters, acrylic amides, such, for example, as methacrylic amide, aromatic vinyl compounds, such, for example, as styrene, isoolefins, such, for example, as isobutylene, copolymers based on the aforementioned compounds, such, for example, as copolymers of vinyl chloride and butyl acrylate, vinylidene chloride and butyl acrylate, synthetic elastomers, such, for example, as copolymers of butadiene and styrene, butadiene and acrylonitrile, and also copolymers of dienes with a preponderant proportion of
  • photoconductive inorganic or organic substances for example sulfur and selenium; oxides, sulfides, selenides and iodides of cadmium, mercury, antimony, bismuth, thallium, moylbdenun, aluminum, lead or zinc; arsenic trisulphide; cadmium arsenide; lead chlorate; anthracene; benzidine; anthraquinone; acenaphthene; fluoranthene; naphthalene; chrysene; quinone; gallic acid; and microcrystalline paraffin wax.
  • sulfur and selenium for example sulfur and selenium; oxides, sulfides, selenides and iodides of cadmium, mercury, antimony, bismuth, thallium, moylbdenun, aluminum, lead or zinc; arsenic trisulphide; cadmium arsenide; lead chlorate; anthracene; benzidine; anthra
  • Terphenyl or p-diphenyl benzene, benzanthrone, 1,5-dicyanonaphthalene, 1,4-dicyanonaphthalene, aminophthalonitrile and nitrophthalonitrile are also particularly suitable.
  • the coating solution which is used for the production of the photoconductive layers comprises at least one of the aforementioned substances and a film-forming binding agent, the electric specific resistance of which must be higher than that of the photoconductive substance and preferably also higher than that of the layer support.
  • binding agents the electric specific resistance of which amounts to at least 10 ohms per centimeter.
  • the quantitative ratios between the photoconductive substances and the binding agents may vary within wide limits. It is preferred to apply the photoconductive substance in amounts of 1 part per 0.3-2 parts by weight of binding agent, and in amounts of 5-60 grams per square meter of photoconductive layer.
  • the photoconductive layer there may be used paper or metal plates, such as zinc, aluminum, or brass plates. Furthermore, thin foils of cellulose hydrate, cellulose esters or of polyamide come into question.
  • the processing of the disclosed materials is carried out in the usual manner.
  • the materials are first made sensitive to light by giving them an electrostatic charge on the coating side in the dark, for instance, by means of a corona discharge.
  • the material is then exposed by any of the conventional photographic procedures.
  • the latent image obtained is developed by applying a pigmented resin powder carrying an electrostatic charge which is opposite to that of the photoconductive layer.
  • Example 1 120 cc. of a 30% aqueous dispersion of a heat-hardenable melamine-formaldehyde resin
  • Example 2 120 cc. of a 30% aqueous dispersion of a melamineformaldehyde resin as described in Example 1,
  • Example 3 100 cc. of a 30% aqueous dispersion of a melamineformaldehyde resin as descibed in Example 1,
  • Example 4 40 g. of zinc oxide are added to 50 cc. of a 35% aqueous emulsion of a copolymer of butadlene-acrylonitrile and styrene (40:40:20) after addition of 80 cc. of water. To this dispersion there are added 1.5 g. of chromium stearoyl chloride. After treating the dispersion for 2 hours in a ball mill, it is coated on a paper support and dried at 70 C.
  • Example 5 40 g. of zinc oxide are added to 100 cc. of a 35% aqueous dispersion of a copolymer of vinyl chloride, and acrylic acid and ethyl acrylate. To this dispersion there are added 25 cc. of an aqueous paraflin wax emul sion. After treating in a ball mill for 2 hours, 100 cc. of water and 10 cc. of ammonia are added. Thereafter the dispersion is cast onto a paper support and dried at 80 C.
  • a process of producing an electrophotographic plate which comprises mixing together in a ball mill zinc oxide, an aqueous dispersion of a heat-hardenable melamineformaldehyde film-forming resinous binding agent in an amount between 0.3 and 2 parts by weight of the resin per part by weight of the zinc oxide, and an aqueous emulsion of paraffin wax in an amount between 2 and 12 percent by weight of the resinous binding agent based on sented by the following quantities:
  • a process of producing an electrophotographic plate which comprises mixing together in a ball mill zinc oxide, an aqueous dispersion of a heat-hardenable melaminedormaildehyde film-forming resinous binding agent in an amount between 0.3 and 2 parts of the resin per part of the zinc oxide, together with a waterproofing substance of the group consisting of (i) an aqueous emulsion of paraffin wax in an amount between 2 and 12 percent by weight of the resinous binding agent based on the paraffin wax content of the emulsion, and

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Medicinal Chemistry (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Photoreceptors In Electrophotography (AREA)
  • Developing Agents For Electrophotography (AREA)
  • Laminated Bodies (AREA)
US696024A 1956-11-14 1957-11-13 Process of preparing photoconductive layers for electrophotography Expired - Lifetime US3128204A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEA26009A DE1082281B (de) 1956-11-14 1956-11-14 Verfahren zur Herstellung von Druckabzuegen nach dem Spiritus-Umdruckverfahren mit Hilfe des elektrophotographischen Verfahrens unter Verwendung von photoleitfaehigen Schichten

Publications (1)

Publication Number Publication Date
US3128204A true US3128204A (en) 1964-04-07

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US (1) US3128204A (en))
BE (2) BE562338A (en))
CH (1) CH369020A (en))
DE (1) DE1082281B (en))
FR (1) FR1190060A (en))
GB (2) GB883783A (en))

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3454415A (en) * 1964-05-25 1969-07-08 Lumiere Soc Process for the manufacture of an electrophotographic material
US3460963A (en) * 1964-05-25 1969-08-12 Lumiere Soc Process for the manufacture of an electrophotographic material
US3481738A (en) * 1966-09-21 1969-12-02 Ball Brothers Co Inc Presensitized photoengraving plate and method of making same
US3540886A (en) * 1968-06-25 1970-11-17 Desoto Inc Acidic photoconductive resin binders
US3691105A (en) * 1970-05-12 1972-09-12 Kiyoshi Juna Compositions for electrosensitive recording material
US3922448A (en) * 1973-05-21 1975-11-25 Ici America Inc Water-soluble polyester resin electrographic coatings
US3923509A (en) * 1973-05-21 1975-12-02 Ici America Inc Water-soluble polyester resins as binders for photoconductors
US4123271A (en) * 1974-01-22 1978-10-31 Mita Industrial Company, Limited Alkali metal dichromate as memory resistance improver for zinc oxide photoconductors in electrostatic photography

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE587794A (en)) * 1960-02-19
US3607527A (en) * 1967-06-05 1971-09-21 Dymo Industries Inc Addressing methods

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE543624A (en)) * 1954-12-15
US2273040A (en) * 1940-09-26 1942-02-17 Du Pont Chemical process and product
US2287348A (en) * 1939-05-11 1942-06-23 West Virginia Pulp & Paper Co Coating paper
US2391621A (en) * 1943-09-17 1945-12-25 Carbide & Carbon Chem Corp Method of coating paper
US2394009A (en) * 1943-04-30 1946-02-05 American Cyanamid Co Treatment of cellulosic materials
US2399489A (en) * 1943-10-06 1946-04-30 American Cyanamid Co Coating compositions for paper and the like
US2663636A (en) * 1949-05-25 1953-12-22 Haloid Co Electrophotographic plate and method of producing same
US2748095A (en) * 1952-03-13 1956-05-29 Basf Ag Foils and coatings from mixtures of pastes of vinyl chloride polymers and plasticizers and aqueous paraffin wax emulsions
US2875054A (en) * 1956-05-24 1959-02-24 Eastman Kodak Co Preparation of coatings of improved internal strength
US2901348A (en) * 1953-03-17 1959-08-25 Haloid Xerox Inc Radiation sensitive photoconductive member
US2959481A (en) * 1958-12-18 1960-11-08 Bruning Charles Co Inc Electrophotographic recording member and process of producing same
US2990279A (en) * 1956-09-25 1961-06-27 Rca Corp Electrostatic printing
US2993787A (en) * 1955-08-30 1961-07-25 Rca Corp Electrostatic printing
US2997387A (en) * 1957-12-17 1961-08-22 Ozalid Co Ltd Photographic reproduction

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2287348A (en) * 1939-05-11 1942-06-23 West Virginia Pulp & Paper Co Coating paper
US2273040A (en) * 1940-09-26 1942-02-17 Du Pont Chemical process and product
US2394009A (en) * 1943-04-30 1946-02-05 American Cyanamid Co Treatment of cellulosic materials
US2391621A (en) * 1943-09-17 1945-12-25 Carbide & Carbon Chem Corp Method of coating paper
US2399489A (en) * 1943-10-06 1946-04-30 American Cyanamid Co Coating compositions for paper and the like
US2663636A (en) * 1949-05-25 1953-12-22 Haloid Co Electrophotographic plate and method of producing same
US2748095A (en) * 1952-03-13 1956-05-29 Basf Ag Foils and coatings from mixtures of pastes of vinyl chloride polymers and plasticizers and aqueous paraffin wax emulsions
US2901348A (en) * 1953-03-17 1959-08-25 Haloid Xerox Inc Radiation sensitive photoconductive member
BE543624A (en)) * 1954-12-15
FR1136146A (fr) * 1954-12-15 1957-05-09 Rca Corp Compositions et procédés permettant la production d'éléments enregistreurs électrophotographiques
US2993787A (en) * 1955-08-30 1961-07-25 Rca Corp Electrostatic printing
US2875054A (en) * 1956-05-24 1959-02-24 Eastman Kodak Co Preparation of coatings of improved internal strength
US2990279A (en) * 1956-09-25 1961-06-27 Rca Corp Electrostatic printing
US2997387A (en) * 1957-12-17 1961-08-22 Ozalid Co Ltd Photographic reproduction
US2959481A (en) * 1958-12-18 1960-11-08 Bruning Charles Co Inc Electrophotographic recording member and process of producing same

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3454415A (en) * 1964-05-25 1969-07-08 Lumiere Soc Process for the manufacture of an electrophotographic material
US3460963A (en) * 1964-05-25 1969-08-12 Lumiere Soc Process for the manufacture of an electrophotographic material
US3481738A (en) * 1966-09-21 1969-12-02 Ball Brothers Co Inc Presensitized photoengraving plate and method of making same
US3540886A (en) * 1968-06-25 1970-11-17 Desoto Inc Acidic photoconductive resin binders
US3691105A (en) * 1970-05-12 1972-09-12 Kiyoshi Juna Compositions for electrosensitive recording material
US3922448A (en) * 1973-05-21 1975-11-25 Ici America Inc Water-soluble polyester resin electrographic coatings
US3923509A (en) * 1973-05-21 1975-12-02 Ici America Inc Water-soluble polyester resins as binders for photoconductors
US4123271A (en) * 1974-01-22 1978-10-31 Mita Industrial Company, Limited Alkali metal dichromate as memory resistance improver for zinc oxide photoconductors in electrostatic photography

Also Published As

Publication number Publication date
CH369020A (de) 1963-04-30
GB883784A (en) 1961-12-06
BE562338A (en))
BE562337A (en))
GB883783A (en) 1961-12-06
FR1190060A (fr) 1959-10-09
DE1082281B (de) 1960-05-25

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