EP0002238A1 - Eléments électrophotographiques et procédé pour leur fabrication - Google Patents

Eléments électrophotographiques et procédé pour leur fabrication Download PDF

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Publication number
EP0002238A1
EP0002238A1 EP78101449A EP78101449A EP0002238A1 EP 0002238 A1 EP0002238 A1 EP 0002238A1 EP 78101449 A EP78101449 A EP 78101449A EP 78101449 A EP78101449 A EP 78101449A EP 0002238 A1 EP0002238 A1 EP 0002238A1
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EP
European Patent Office
Prior art keywords
dye
layer
ylidene
diphenyl
photoconductive
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.)
Granted
Application number
EP78101449A
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German (de)
English (en)
Other versions
EP0002238B1 (fr
Inventor
Jerome Howard Perlstein
George Arthur Reynolds
James Albert Vanallan
Suzanne Patricia Clark
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Eastman Kodak Co
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Eastman Kodak Co
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Publication date
Application filed by Eastman Kodak Co filed Critical Eastman Kodak Co
Publication of EP0002238A1 publication Critical patent/EP0002238A1/fr
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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, 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
    • G03G5/0622—Heterocyclic compounds
    • G03G5/0644—Heterocyclic compounds containing two or more hetero rings
    • G03G5/0661—Heterocyclic compounds containing two or more hetero rings in different ring systems, each system containing at least one hetero ring
    • 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
    • G03G5/0664—Dyes
    • G03G5/0666—Dyes containing a methine or polymethine group
    • G03G5/0668—Dyes containing a methine or polymethine group containing only one methine or polymethine group
    • G03G5/067—Dyes containing a methine or polymethine group containing only one methine or polymethine group containing hetero rings

Definitions

  • This invention relates to electrophotography and particularly to light sensitive materials for phctocondue- tive compositions.
  • One- type of photoconductive element particularly useful in electrophotography employs a layer containing a photoconductive material and an electrically insulating, film-forming, resinous binder.
  • a photoconductive element In many uses, it is desirable for a photoconductive element to exhibit high speed (as measured by an electrical speed or characteristic curve), a low residual potential after exposure, and resistance to electrical fatigue. Sometimes it is also desirable that the photoccn- ductive element be capable of accepting a high surface potential and have a low rate of dark decay.
  • High speed photoconductive elements which exhibit many of the desirable qualities mentioned above have been developed. Such high speed elements are referred to as “aggregate” or “heterogeneous” elements, and are described in U.S. Patent 3,615,414 issued October 26, 1971 to Light, and U.S. Patent 3,732,180 issued May 8, 1973 to Gramza et al.
  • the "aggregate” photoconductive elements of these patents comprise one or more photoconductive layers which contain a continuous polymer phase having dispersed therein co-crystalline particles of a pyrylium or thiopy- rlium salt and a polymer.
  • thiopyrylium dye salts in photoconductive layers is also disclosed in U.S. 3,973,962, issued August 10, 1976, to Contois et al, and U.S. 3,250,615 issued May 10, 1966 to Van Allen et al.
  • Certain monomethine thiopyrylium dye salts are also disclosed as sensitizers for photoconductors in U.S. 3,938,994 issued February 17, 1976 to Reynolds et al.
  • the present invention provides an electrophotographic element comprising a photoconductive layer on a conductive support.
  • the photoconductive layer contains an electrically insulating binder and a dye.
  • the dye in this layer is in the form of a "dye-dye interaction" which can be (a) formed by treatment of the layer with a solvent for the dye and is (b) polymer-independent, as explained hereinafter.
  • the dyes which are useful in this invention have structures according to Formula I: wherein Z and Z may be the same or different and represent 0, Se and S, and X ⁇ represents an anion such as perchlorate or fluoroborate.
  • the present invention also comprises a method of making the electrophotographic element of the present invention, which method includes treating the layer containing the binder, the dye and, optionally, an organic photoconductor with solvent vapor.
  • die-dye interaction is used herein to refer to the condition of the dye in the electrophotographic element of our invention. Although the nature of the combination of the dye molecules with each other is not certain, the observed facts indicate that the dye molecules are present in a close molecular relationship with each other which differs distinctly from the co-crystalline dye-polymer "aggregate" of the prior art. Hence the name “dye-dye interaction” is used herein to identify the condition of the dye in our novel element.
  • electrophotographic elements which contain one or more of the dyes described herein in the "dye-dye interaction" condition surprisingly exhibit enhanced speed, as compared to an element which is otherwise identical, but which has not been treated to produce the "dye-dye interaction” condition.
  • the electrophotographic elements of this invention also exhibit a better relationship of speed ana image resolution (referred to herein as "speed-resolution p,, d duct"), as compared with many electrophotographic elements of the prior art.
  • speed-resolution p,, d duct speed-resolution p,, d duct
  • the drawing shows the absorption spectrum of a photoconductive layer containing a binder and one of the dyes which we have discovered can be transformed to the "dye-dye interaction" condition.
  • transformed photoconductive layer is intended to mean a photoconductive layer of this invention which contains dye in the "dye-dye interaction" condition as described herein.
  • the electrophotographic elements of this invention are readily distinguishable from the so-called "aggregate” photoconductive elements of the prior art.
  • our photoconductive layers have dye in'the "dye-dye interaction” condition
  • aggregate photoconductive layers contain dye in a "dye-polymer interaction” condition.
  • Dyes useful in "aggregate” photoconductive layers react with a polymer in the layer, and are polymer-dependent (i.e. only certain polymers can be used to produce the "dye-polymer interaction" product).
  • Our layers contain dyes which are not dependent upon a particular type of polymer for their valuable electrophotographic properties, and are therefore "polymer-independent".
  • the absorption spectra of the pyrylium dye salts used to form the aforementioned "aggregate" photoconductive layers also change when a binderless coating of such dye salts is treated with solvent vapors.
  • the absorption spectra of vapor-treated layers comprising an electrically insulating binder polymer and the aforementioned pyrylium dyes are different from that of a vapor-treated binderless coating of the pyrylium dye.
  • a photoconductive layer is provided, as described, which also contains an organic photoconductor.
  • Useful dyes within the scope of general Formula I include the dyes shown in Table I.
  • the symmetrical pyrylium and thiopyrylium monomethine dyes of Formula I may be prepared according to the procedure described in U.S. Patent 3,938,994.
  • the preparation of the sulfur-oxygen unsymmetrical monomethine pyrylium dyes is taught by G. A. Reynolds and J. A. Van Allan, J. Heterocylic Chem., 9, 1105 (1972).
  • the preparation of symmetrical monomethine selenopyrylium, as well as thiopyrylium dyes, is taught by A. J. Tolmachev and M. A. Kudinova, Khimiya Geterotsiklicheskikh Soedinenii, 49 (1974).
  • the unsymmetrical selenopyrylium dyes which are new compositions of matter, can be prepared as follows.
  • Z represents 0 or S.
  • a mixture of 0.31 g of (II) and 0.35 g of (III) in 10 ml of acetic anhydride was heated under reflux for 30 minutes and cooled to room temperature during which time glistening needles of the desired material formed.
  • the photoconductive layers of the present invention are transformed photoconductive layers comprising a dye as previously described and an electrically insulating binder.
  • the transformation is the result of solvent action on the dye.
  • the transformation can be carried out in several ways. For example, a solution containing the selected dye, the electrically insulating polymer and, if desired, an organic photoconductor can be coated onto a suitable support. The solvent is then evaporated. Transformation of the dye is then achieved by contact of the resulting layer with the vapors of solvent until a color change in the layer occurs. Also transformation can be achieved by inhibiting solvent removal in an otherwise normal coating operation of a solvent dope containing the dye and polymer. Similarly, coating such a layer from a solvent mixture which also contains solvent which persists in the coating during drying is among the methods for achieving the desired transformation.
  • the photoconductive layers of the examples have been prepared by mixing together separate solutions of the selected dye and the electrically insulating polymer and then adding an organic photoconductor.
  • the resulting coating solution is then coated on a conductive support, such as a nickel-coated poly(ethylene terephthalate) film support, and dried in air or under vacuum at- about 60°C for about one hour.
  • the coated layer is then treated with a solvent vapor for a few minutes and then redried under vacuum for about one hour at about 60°C.
  • the organic solvents useful for preparing coating solution can be selected from a variety of solvents.
  • the requisite properties of the solvent are that it be capable of dissolving the selected dye and be capable of dissolving or at least highly swelling or solubilizing the polymer in the layer.
  • the solvent is volatile, preferably having a boiling point of less than 200°C.
  • Particularly useful solvents include halogenated lower alkanes having from 1 to 3 carbon atoms.
  • the solvents useful in achieving the desired transformation of dye include, among others, dichloromethane, toluene, tetrahydrofuran, p-dioxane, chloroform and l,l,l-trichloroethane. Such solvents may be used alone or in combination with other volatile organic liquids.
  • the desired transformation is indicated by a change in the absorption spectrum of the photoconductive layer.
  • the amount of the selected dye incorporated into photoconductive layers and elements of the present invention can be varied over a relatively wide range.
  • the dye may be present in an amount of 0.01 to 50.0 percent by weight of the coated layer on a dry basis.
  • the photoconductive layer includes an organic photoconductor, useful results are obtained by using the dye in amounts of 0.1 to 30 percent by weight of the photoconductive layer.
  • the upper limit of the amount of dye is a matter of choice and the amount of any dye used will vary widely depending on the particular dye selected, the electrophotographic response desired, the proposed structure of the photoconductive element and the mechanical properties desired in the element.
  • Conventional electrically insulating film-forming polymers are useful in the present invention.
  • Such polymers include polystyrene, polyvinylethers, polyolefins, poly- thiocarbonates, polycarbonates, and phenolic resins such as those disclosed in U.S. Patent 3,615,414. Mixtures of such polymers are also useful.
  • Particularly useful polymers have recurring units as shown in Table II.
  • Useful organic photoconductors are generally electron acceptors or electron donors for the dyes. They include the organic photoconductors described in the patent literature such as those disclosed in U.S. Patent 3,615,414; U.S. Patent 3,873,311; U.S. Patent 3,873,312 and Research Disclosure 10938, Volume 109, May, 1973. Aromatic amines such as tri-p-tolylamine and (di-p-toly- laminophenyl)cyclohexane are particularly useful.
  • organic photoconductors when used, are present in our photoconductive layers in an amount equal to at least 1 weight percent of the combined dry weight of dye, binder, and organic photoconductor in the layer(s).
  • the organic photoconductor can be present in the layer up to the limit of its solubility in the polymeric binder.
  • a polymeric organic photoconductor may also be employed either as the binder or with another polymeric binder.
  • a preferred weight range for the organic photoconductor in the photoconductive layer is from 10 to 40 weight percent.
  • a wide variety of electrically conducting supports can be used in the practice of this invention, for example, paper (at a relative humidity above 20 percent); aluminum-paper laminates; metal foils such as aluminum foil, zinc foil, etc.; metal plates such as aluminumcop- per, zinc, brass and galvanized plates; vapor-deposited metal layers such as silver, chromium, nickel, aluminum, cermet materials and the like coated on paper.
  • Conventional photographic film bases such as cellulose acetate, poly(ethyleneterephthalate) or polystyrene can also be used.
  • Conducting materials such as nickel can be vacuum deposited on transparent film supports in sufficiently thin layers to allow electrophotographic elements prepared therewith to be exposed from either side of such elements.
  • An especially useful conducting support can be prepared by coating a film of poly(ethylene terephthalate) with a conducting layer containing a semiconductor dispersed in resin.
  • the photoconductive layers can be coated, if desired, directly on a conducting substrate.
  • Such subbing layers typically have a dry thickness in the range of 0.1 to 5 microns.
  • Optional overcoat layers may be used in the present invention.
  • the surface layer of the element of the invention may be coated with one or more electrically insulating, organic polymer coatings or electrically insulating, inorganic coatings.
  • electrically insulating, organic polymer coatings or electrically insulating, inorganic coatings are well known in the art.
  • Typical useful overcoats are disclosed, for example, in Research Disclosure "Electrophotographic Elements, Materials, and Processes", Volume 109, page 63, Paragraph V, May, 1973.
  • Coating thickness of the photoconductive layer of the support can vary widely. Normally, a coating in the range of about 0.5 microns to about 300 microns before drying is useful for the practice of this invention. The preferred range of coating thickness is found to be in the range from about 1.0 microns to about 150 microns before drying) although useful results can be obtained outside cf this range. The resultant dry thickness of the coating is preferably between 2 microns and 50 microns, although useful results can be obtained with a dry coating thickness between 1 and 200 microns.
  • Transformation of the dye to the "dye-dye interaction" condition was observed as a change in color when the layer was fumed with tetrahydrofuran vapor.
  • the layer was fumed by suspending it in a Dewar flask which was saturated with the vapor.
  • the flask, fitted for optical access, was placed into a Cary 14 spectrophotometer and the film's optical spectrum was recorded.
  • the amount of time required to form the enhanced photoconductive state of the dye appeared to be dependent on the concentration of solvent fumes in contact with the surface of the layer.
  • the unfumed film appeared blue-given by transmitted light. Upon solvent treatment for one minute with the vapors of methylene chloride, the film turned blue.
  • the optical absorption spectrum for this film before and after vapor treatment is shown in the drawing.
  • the absorption spectrum was determined in a conventional manner using a Cary 14 spectrophotometer.
  • the absorption spectrum 1 for the untreated film had a peak at about 650 nm and a shoulder at 600 nm.
  • the spectrum 2 for the methylene chloride fumed film is shifted with narrow peaks at 635 nm and 560 nm.
  • the untreated film did not have a peak at 560 nm.
  • the photosensitivity of each sample was determined as follows: the surface of the layer away from the support was electrostatically'charged negatively under a corona source until the surface potential as measured by a capacitively-coupled probe attached to an electrometer attained an initial dark value, V o of -500 volts. The rear surface of the charged element was then exposed to monochromatic visible radiation at a wavelength of 640 nm. The exposure caused reduction of the surface potential of the element from -500 volts to -100 volts.
  • the photosensitivity of the element can be considered equivalent to the exposure in ergs/cm 2 necessary to discharge the element from -500 to -100 volts, after correction for light absorption and reflection by the film support.
  • a photoconductive layer containing dye 3 (Table I) was tested as in Example 2. Upon vapor treatment the layer changed from blue-green to blue and exhibited the same absorption and speed characteristics as dye 1 (Table 1).
  • the control was a layer of the same material which was not fumed with toluene.
  • the control had maximum absorption at 660 nm and a shoulder at 620 nm.
  • the transformed layer i.e., vapor treated to form the enhanced photoconductive state
  • the photosensitivity of the treated layer and untreated control layer was determined as in Example 2 for negative charging, front and rear exposure. Results are shown in Table IV.
  • Element A contained a homogenous photoconductive layer of the type described in U.S. Patent 3,542,547.
  • Element B contained an "aggregate" photoconductive layer of the type described in U.S. Patent 3,873,311.
  • Elements C and D are of this invention and contain dye 1 in their photoconductive layers (Table I). These layers contained the following materials.
  • Each coating solution was made 24 hours prior to the coating step by dissolving the components in the order listed and allowing sufficient time between additions for complet. solvation.
  • Each solution was coated on a transparent substrate
  • Layer A was made at a coverage of 7.5 gms/m.
  • Layer B was made at a coverage of 11.3 gms/m.
  • Layers C and D were made at a coverage of 7.5 gms/m 2 . (Coverages are in terms of dry basis.)
  • the coatings were then dried. In this instance, it was not necessary to carry out a separate solvent fuming step, since the coating solutions for layers C and D contained toluene in addition to methylene chloride. The presence of toluene was sufficient to result in the formation of the "dye-dye interaction" condition before all of the toluene had evaporated from the layer.
  • Photosensitivity and resolution data are presented in Table V. Photosensitivity was determined as in Example 2 for negative charging at a wavelength where the optical density of the film equals 1.0. Discharge was from -600V to -100V. The data in this table shows that electrophotographic elements of the present invention have a higher speed-resolution product than the photoconductive elements A and B which are representative of the prior art
  • the fumed element was dried in a vacuum oven at 60°C for one hour.
  • the absorption spectrum of this element after treatment with solvent vapor had a shoulder at 578 nm and a peak at 605 nm.
  • the spectrum of the unfumed element was different from that of the fumed element.
  • Photosensitivity measurements were made as in Example 2 for rear exposure discharge from -500V to -100V.
  • the photosensitivity of the fumed element was 13 erg/cm 2 .

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Photoreceptors In Electrophotography (AREA)
EP19780101449 1977-11-28 1978-11-24 Eléments électrophotographiques et procédé pour leur fabrication Expired EP0002238B1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US85514177A 1977-11-28 1977-11-28
US87497178A 1978-02-03 1978-02-03
US874971 1986-06-16
US855141 2004-05-27

Publications (2)

Publication Number Publication Date
EP0002238A1 true EP0002238A1 (fr) 1979-06-13
EP0002238B1 EP0002238B1 (fr) 1984-06-13

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EP (1) EP0002238B1 (fr)
JP (1) JPS5483837A (fr)
CA (1) CA1129426A (fr)
DE (1) DE2862416D1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0056727B1 (fr) * 1981-01-19 1985-01-16 EASTMAN KODAK COMPANY (a New Jersey corporation) Elément photoconductif sensible à la lumière infrarouge
US7604913B2 (en) * 2004-07-16 2009-10-20 Mitsubishi Chemical Corporation Electrophotographic photosensitive body

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JPS6377933A (ja) * 1986-09-22 1988-04-08 Daicel Chem Ind Ltd ポリカ−ボネ−ト樹脂光学成型品
JP4847245B2 (ja) * 2005-08-15 2011-12-28 キヤノン株式会社 電子写真感光体、プロセスカートリッジおよび電子写真装置
JP4847305B2 (ja) * 2005-12-20 2011-12-28 キヤノン株式会社 電子写真感光体、プロセスカートリッジおよび電子写真装置
CN102221793B (zh) 2006-01-06 2013-07-31 三菱化学株式会社 电子照相感光体以及使用该电子照相感光体的成像装置和电子照相感光体盒
JP5040319B2 (ja) * 2006-01-13 2012-10-03 三菱化学株式会社 正帯電型電子写真感光体、画像形成装置、画像形成方法及び電子写真感光体カートリッジ
JP4862662B2 (ja) * 2006-01-13 2012-01-25 三菱化学株式会社 電子写真感光体並びにそれを用いた画像形成装置及び電子写真カートリッジ
JP4862661B2 (ja) * 2006-01-13 2012-01-25 三菱化学株式会社 感光層形成用塗布液、電子写真感光体、電子写真感光体カートリッジ及び画像形成装置
JP5040318B2 (ja) * 2006-01-13 2012-10-03 三菱化学株式会社 感光層形成用塗布液、電子写真感光体、電子写真感光体カートリッジ及び画像形成装置
JP2007213050A (ja) * 2006-01-13 2007-08-23 Mitsubishi Chemicals Corp 画像形成装置
JP4862660B2 (ja) * 2006-01-16 2012-01-25 三菱化学株式会社 電子写真感光体
JP4847251B2 (ja) * 2006-03-10 2011-12-28 キヤノン株式会社 電子写真感光体、プロセスカートリッジおよび電子写真装置
JP2007298952A (ja) * 2006-04-06 2007-11-15 Canon Inc 電子写真感光体、電子写真感光体の製造方法、プロセスカートリッジ及び電子写真装置
JP4878237B2 (ja) * 2006-07-31 2012-02-15 キヤノン株式会社 電子写真感光体の製造方法
JP4847247B2 (ja) * 2006-07-31 2011-12-28 キヤノン株式会社 電子写真感光体の製造方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1299226B (de) * 1961-04-07 1969-07-10 Minnesota Mining & Mfg Elektrophotographisches Aufzeichnungsmaterial fuer mehrfarbige Bilder
FR2105830A5 (en) * 1970-08-03 1972-04-28 Eastman Kodak Co Electrophotographic sensitisers - bispyrylium salts for org photo conductors increased sensitivity
UST904032I4 (en) * 1972-11-21 Defensive publication
DE2221135A1 (de) * 1971-04-30 1972-11-23 Mitsubishi Paper Mills Ltd Elektrophotographisches Material mit grosser Empfindlichkeit und Verfahren zum Sensibilisieren dieses Materials
USRE28698E (en) * 1970-03-13 1976-01-27 Matsushita Electric Industrial Co., Ltd. Electrophotographic material containing sensitizers
US3938994A (en) * 1972-03-17 1976-02-17 Eastman Kodak Company Pyrylium dyes for electrophotographic composition and element

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
UST904032I4 (en) * 1972-11-21 Defensive publication
DE1299226B (de) * 1961-04-07 1969-07-10 Minnesota Mining & Mfg Elektrophotographisches Aufzeichnungsmaterial fuer mehrfarbige Bilder
USRE28698E (en) * 1970-03-13 1976-01-27 Matsushita Electric Industrial Co., Ltd. Electrophotographic material containing sensitizers
FR2105830A5 (en) * 1970-08-03 1972-04-28 Eastman Kodak Co Electrophotographic sensitisers - bispyrylium salts for org photo conductors increased sensitivity
DE2221135A1 (de) * 1971-04-30 1972-11-23 Mitsubishi Paper Mills Ltd Elektrophotographisches Material mit grosser Empfindlichkeit und Verfahren zum Sensibilisieren dieses Materials
US3938994A (en) * 1972-03-17 1976-02-17 Eastman Kodak Company Pyrylium dyes for electrophotographic composition and element

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DERWENT JAPANESE PATENTS REPORT vol. U, no. 52, Januray 1974, London U.K. Part G, page 5, column 2, paragraph 3; & JP-B-48 043 151 (MATSUSHITA ELECTRIC INDUSTRIAL CO.). *
RESEARCH DISCLOSURES, no. 99, July 1972, Abstract no. 9911, Hampshire U.K. "Method for improving image visibility of organic photoconductive elements", pages 43-44. *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0056727B1 (fr) * 1981-01-19 1985-01-16 EASTMAN KODAK COMPANY (a New Jersey corporation) Elément photoconductif sensible à la lumière infrarouge
US7604913B2 (en) * 2004-07-16 2009-10-20 Mitsubishi Chemical Corporation Electrophotographic photosensitive body
US7985522B2 (en) * 2004-07-16 2011-07-26 Mitsubishi Chemical Corporation Electrophotographic photoreceptor

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JPS6248214B2 (fr) 1987-10-13
CA1129426A (fr) 1982-08-10
EP0002238B1 (fr) 1984-06-13
DE2862416D1 (en) 1984-07-19
JPS5483837A (en) 1979-07-04

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