And Radioactive Or Ultraviolet Light Ionizer Patents (Class 96/16)
  • Patent number: 4088482
    Abstract: Photoconductive compositions containing aromatic sulfonyl fluorides are novel compositions which are useful in electrophotographic processes, such as xerography. E.g., an electrostatic copying paper is obtained by coating an electroconductive base paper with a composition comprising poly(N-vinylcarbazole) and 4,4'-biphenyldisulfonyl fluoride.
    Type: Grant
    Filed: July 13, 1971
    Date of Patent: May 9, 1978
    Assignee: The Dow Chemical Company
    Inventors: Ralph G. Czerepinski, Jeffrey K. Hecht, Thomas T. Chiu
  • Patent number: 4082750
    Abstract: Trinitro-11H-indeno[1,2-b]quinoxaline-11-one obtained by further nitrating 11H-indeno[1,2-b]quinoxaline-11-one, or mononitro- or dinitro-derivatives thereof, demonstrates a conspicuous sensitization effect with respect to organic photoconductors.
    Type: Grant
    Filed: October 20, 1976
    Date of Patent: April 4, 1978
    Assignee: Ricoh Co., Ltd.
    Inventor: Masafumi Ohta
  • Patent number: 4082550
    Abstract: Photoconductive insulating compositions in the form of organic photoconductive dispersions are described. Particles of organic photoconductor such as p-terphenyl are dispersed in cellulose nitrate and chemically sensitized with monomeric hexachlorocyclopentenes to provide useful heterogeneous photoconductive insulating dispersions. Such dispersions can be applied to an electrically conducting support to prepare electrophotographic elements.
    Type: Grant
    Filed: May 25, 1977
    Date of Patent: April 4, 1978
    Assignee: Eastman Kodak Company
    Inventor: William E. Yoerger
  • Patent number: 4072520
    Abstract: This invention relates to an electrophotographic recording material consisting of an electroconductive support material and a photoconductive double layer of organic materials which consists of a homogeneous, opaque, charge carrier producing dyestuff layer and of a transparent top layer of insulating materials with at least one charge transporting compound.
    Type: Grant
    Filed: April 25, 1973
    Date of Patent: February 7, 1978
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Jurgen Rochlitz, Gunter Schon
  • Patent number: 4066454
    Abstract: Electrophotographic light-sensitive materials having a photoconductive layer formed on an electroconductive support, the photoconductive layer comprising an organic photoconductive compound (monomer or polymer) and indenothiophenone or its derivative as a sensitizer, and a process of preparing indenothiophenone and its derivatives from a benzoic acid derivative and a thiophene derivative.
    Type: Grant
    Filed: October 3, 1975
    Date of Patent: January 3, 1978
    Assignee: Kabushiki Kaisha Ricoh
    Inventor: Mitsuru Hashimoto
  • Patent number: 4066455
    Abstract: A multi-active photoconductive element is disclosed having at least three layers in electrical contact with one another, said layers comprising a photoconductive selenium-containing layer, a charge-generation layer and an organic photoconductor-containing charge-transport layer. The charge-generation layer contains a continous polymeric phase having dispersed therein a co-crystalline complex composed of (i) at least one polymer having an alkylidene diarylene group in a recurring unit and (ii) at least one pyrylium-type dye salt. The multi-active element of the invention exhibits improved sensitivity to blue light.
    Type: Grant
    Filed: November 5, 1975
    Date of Patent: January 3, 1978
    Assignee: Eastman Kodak Company
    Inventors: William Mey, David S. Bailey
  • Patent number: 4063947
    Abstract: Composite photoconductive insulating films comprising a thin layer of photoconductive materials having substantial spectral response in the visible region of the electromagnetic spectrum and a substantially colorless insulating layer contiguous therewith comprising a minor portion of electronically inert binder in a major portion of an electronically active oligomer of the formula: ##STR1## R' is hydrogen or methyl; R" is alkyl of 1-10 carbon atoms;X and Y are independently selected from the group consisting of NO.sub.2, halogen, cyano and --CF.sub.3 ;Z is oxygen or dicyanomethylene;a and a' can range from 0-3;m is 1-10; andn is in the range of from about 3 to about 25.
    Type: Grant
    Filed: October 29, 1975
    Date of Patent: December 20, 1977
    Assignee: Xerox Corporation
    Inventors: John M. Pochan, Sam R. Turner
  • Patent number: 4063946
    Abstract: A xerographic color reproduction imaging system is disclosed. This color system provides at least a two color image with one exposure and avoids the necessity of employing a registration step. A sensitized photoconductive layer is employed which is charged, selectively exposed and developed with a color toner. The photoconductive layer is then recharged and developed with toner of another color.
    Type: Grant
    Filed: January 22, 1973
    Date of Patent: December 20, 1977
    Assignee: Rank Xerox Ltd.
    Inventors: Yasuo Tamai, Sadao Osawa
  • Patent number: 4063948
    Abstract: This invention relates to a material for electrophotographic reproduction, which comprises a conductive support having a sensitized photoconductive insulating layer thereon containing at least one photoconductor and containing, as a sensitizer, a polymethine dyestuff capable of absorbing radiation of a wavelength within the spectral range of 400 to 550 nm.
    Type: Grant
    Filed: June 10, 1976
    Date of Patent: December 20, 1977
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Erwin Lind
  • Patent number: 4055421
    Abstract: The present invention provides 1,3,7-trinitrophenazine-5-oxide which has an excellent sensitization effect on organic photoconductors, as well as a photoconductive sensitive material comprising said compound and an organic photoconductor.
    Type: Grant
    Filed: December 10, 1975
    Date of Patent: October 25, 1977
    Assignee: Ricoh Co., Ltd.
    Inventor: Masafumi Ohta
  • Patent number: 4054450
    Abstract: Fading of the light-sensitivity of a dye-sensitized photoconductive layer used repeatedly for image formation in indirect electrophotographic copying is avoided by employing a photoconductive layer sensitized by a nitro-substituted dye such as a nitro-fluorescein or a nitro-phenolsulfonephthalein.
    Type: Grant
    Filed: June 27, 1974
    Date of Patent: October 18, 1977
    Assignee: Oce-van der Grinten N.V.
    Inventors: Bauke Schoustra, Hubertus W. H. M. Roncken
  • Patent number: 4054712
    Abstract: An electrophotographic method comprises developing an electric latent image formed on a photosensitive member comprising a photoconductive material and containing a first color forming agent in a surface for forming a visible image with a charged toner particle containing a second color forming agent, and heating to cause a thermal color forming reaction therebetween resulting in formation of a colored fixed image on the photosensitive member.
    Type: Grant
    Filed: March 20, 1975
    Date of Patent: October 18, 1977
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shinichiro Nagashima, Kaichi Tsuchiya, Yoshihiro Sakamoto, Hiroshi Yamakami, Seiji Tomari
  • Patent number: 4053311
    Abstract: A photosensitive member having at least two electrically operative layers is disclosed. The first layer comprises a photoconductive layer which is capable of photogenerating holes and injecting the photo-generated holes into a contiguous charge transport layer. The charge transport layer comprises poly(N-vinylcarbazole) which contains an electrically active plasticizer comprising from about 1 to about 25 percent by weight of bis(4-diethylamino-2-methylphenyl)phenylmethane. The charge transport layer while substantially non-absorbing in the spectral region of intended use, is "active" in that it allows injection of photo-generated holes from the photoconductive layer, and allows these holes to be transported through the charge transport layer. This structure may be imaged in the conventional xerographic mode which usually includes charging, exposure to light and development.
    Type: Grant
    Filed: April 2, 1976
    Date of Patent: October 11, 1977
    Inventors: William W. Limburg, John F. Yanus, Damodar M. Pai
  • Patent number: 4052209
    Abstract: Semiconductive compositions are produced by the inclusion of a particular class of dyes into a polymeric binder. When the binder is an organic photoconductive binder, the dyes act as exceptionally good sensitizers for the photoconductive material.
    Type: Grant
    Filed: March 7, 1975
    Date of Patent: October 4, 1977
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: William A. Huffman, Stephen P. Birkeland, Kevin P. O'Leary
  • Patent number: 4052210
    Abstract: In electrophotographic copying processes use is made of a reproduction element comprising on a conductive support a photoconductive layer containing dispersed in a binder a bisazo naphthol compound having a certain structure of substituents whereby the reproduction element exhibits relatively high light-sensitivity and is repeatedly exposable and developable imagewise so as to be useful for indirect electrophotographic copying. Special binder compositions enhance the light-sensitivity of the element and special layer constructions are provided to suit it for certain uses.
    Type: Grant
    Filed: June 30, 1976
    Date of Patent: October 4, 1977
    Assignee: Oce-van der Grinten N.V.
    Inventor: Adrianus M. P. Hectors
  • Patent number: 4050935
    Abstract: A photosensitive member having at least two electrically operative layers is disclosed. The first layer comprises trigonal selenium which is capable of photogenerating holes and injecting the photo-generated holes into a contiguous charge transport layer. The charge transport layer comprises a transparent electrically inactive organic resinous material containing from about 15 to about 75 percent by weight (throughout) of bis(4-diethylamino-2-methylphenyl)phenylmethane. The charge transport layer while substantially non-absorbing in the spectral region of intended use, is "active" in that it allows injection of photo-generated holes from the trigonal selenium carrier generating layer, and allows these photo-generated holes to be transported through the charge transport layer. This structure may be imaged in the conventional xerographic mode which usually includes charging, exposure to light and development.
    Type: Grant
    Filed: April 2, 1976
    Date of Patent: September 27, 1977
    Assignee: Xerox Corporation
    Inventors: William W. Limburg, John F. Yanus, Damodar M. Pai
  • Patent number: 4051123
    Abstract: In a first main aspect azo dyestuffs of the formula ##STR1## wherein A, B, X and Y are certain substituents, in a second main aspect azo dyestuffs of the formula ##STR2## wherein B' represents certain substituents and in a third main aspect azo dyestuffs of the formulaA.sub.1 --N.dbd.N--B.sub.1 --NH--CO--X.sub.1 --Y--Z.sub.1 --OC--HN--B.sub.1 --N.dbd.N--A.sub.1wherein A.sub.1, B.sub.1, X.sub.1, Z.sub.1 and Y are certain substituents as well as the use of said azo dyestuffs in photographic material are disclosed.
    Type: Grant
    Filed: August 21, 1975
    Date of Patent: September 27, 1977
    Assignee: Ciba-Geigy AG
    Inventors: Bernhard Piller, John Lenoir, Alfred Froehlich, Thomas Stauner, Paul Tschopp
  • Patent number: 4046563
    Abstract: Photoconductive composition comprising an insulating polymeric matrix and a compound of the formula ##STR1## wherein R is --H or --CN;R', r", r'" and R.sup.iv are independently selected from an aliphatic hydrocarbon radical having from about 1-10 carbon atoms; phenyl; or substituted phenyl wherein said substituents are capable of releasing electrons to relatively electron deficient centers within the compound; amino; diarylamino; dialkylamino or alkoxy; n can range from 0 up to the potential number of positions of substitution on the aromatic ring system.These compositions have good spectral response in the visible region of the electromagnetic spectrum and are suitable for use in electrostatographic imaging members and methods.
    Type: Grant
    Filed: February 10, 1975
    Date of Patent: September 6, 1977
    Assignee: Xerox Corporation
    Inventors: James M. Pearson, David J. Williams, William W. Limburg
  • Patent number: 4045220
    Abstract: Coloration resistant photoconductive insulating compositions useful in making elements, such as photoconductive electrophotographic papers, are provided. Such compositions comprise (1) an electrically insulating organic binder, (2) a nitrogen-free polyaryl hydrocarbon photoconductor such as those having the formula ##STR1## wherein: N REPRESENTS AN INTEGER HAVING A VALUE OF 0, 1 OR 2,Ar represents an aryl group including substituted aryl such as phenyl, alkylphenyl having 1 to about 10 carbon atoms in the alkyl moiety, alkoxyphenyl having 1 to about 10 carbon atoms in the alkoxy moiety, and the like,Each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 represents a hydrogen atom, an aryl group, an alkyl group or an alkoxy group and, when n is O, R.sup.1 and R.sup.4 are both aryl and when R.sup.1 and R.sup.4 are both hydrogen, each of R.sup.2 and R.sup.3 represents an aryl group; and (3) a sensitizer that is substantially non-color forming in the composition.
    Type: Grant
    Filed: July 14, 1975
    Date of Patent: August 30, 1977
    Assignee: Eastman Kodak Company
    Inventors: Lawrence E. Contois, Charles J. Fox, Richard W. Stahr
  • Patent number: 4042388
    Abstract: The photosensitivity of organic photoconductive materials can be improved by reactively mixing a free radical former having a free radical produced by irradiation of a dye base compound and an organic photoconductive materials with radiation energy.
    Type: Grant
    Filed: April 2, 1973
    Date of Patent: August 16, 1977
    Assignee: Canon Kabushiki Kaisha
    Inventors: Eiichi Inoue, Ichiro Endo, Teruo Yamanouchi
  • Patent number: 4040825
    Abstract: The present invention relates to light-sensitive photographic material with a light-sensitive heavy metal compound, e.g. a silver halide, and a spectral sensitizer. The spectral sensitizer is a compound in which the radicals of a sensitizing dyestuff are covalently bonded to amino, imino, hydroxyl, mercapto, carboxylic acid or carboxylic acid amide groups of a natural hydrophilic colloid, preferably gelatin.The invention also relates to new sensitizing dyes which are dinuclear cyanine dyes or merocyanine dyes which have attached either to a heterocyclic nucleus of the dye or to its methine chain a group which is reactive with a hydrophilic colloid.
    Type: Grant
    Filed: March 11, 1976
    Date of Patent: August 9, 1977
    Assignee: Ciba-Geigy AG
    Inventors: Rolf Steiger, Jean-Francois Reber, Aaron David Ezekiel, Geoffrey Ernest Ficken
  • Patent number: 4037017
    Abstract: Disclosed is electroconductive paper adapted particularly for use in the manufacture of paper used in the electrophotographic reproduction of images.
    Type: Grant
    Filed: December 8, 1975
    Date of Patent: July 19, 1977
    Assignee: Hercules Incorporated
    Inventor: William Walter Maslanka
  • Patent number: 4033769
    Abstract: Photoconductive compositions comprising an organic photoconductive material, an activator capable of forming a charge transfer complex with the photoconductive material, and a protonic acid. Imaging members provided with an imaging layer prepared from the above composition are highly light sensitive, requiring only brief exposure times, and exhibit a photoinduced state of elevated conductivity which persists long after exposure to light is terminated. These compositions can be returned to their relatively insulative state by merely subjecting the imaging layer to heat in the dark, thereby erasing this photoinduced image pattern of elevated conductivity.
    Type: Grant
    Filed: October 30, 1974
    Date of Patent: July 5, 1977
    Assignee: Xerox Corporation
    Inventors: David J. Williams, Marcel A. Lardon, Martin A. Abkowitz, Gustav Pfister
  • Patent number: 4030923
    Abstract: This invention relates to an improvement in photoconductive compositions of layered electrophotographic plates and related electrophotographic processes and particularly in the charge transport layer thereof which includes a tri-aryl pyrazoline compound in conjunction with a binder material wherein the improvement comprises the use of a tri-aryl pyrazoline compound and a mixture of binder materials comprising about 3 to 25% by weight acrylic resin and about 75 to 97% by weight polycarbonate.
    Type: Grant
    Filed: December 11, 1975
    Date of Patent: June 21, 1977
    Assignee: International Business Machines Corporation
    Inventors: Donald Lester Krause, Kenneth Dale Presley
  • Patent number: 4028102
    Abstract: This invention relates to a compound of the formula ##STR1## wherein R is a phenylene or naphtylene group. The invention also relates to a process for making the novel compounds of the invention and also to an electrophotographic recording material employing the novel compounds of the invention.
    Type: Grant
    Filed: December 5, 1975
    Date of Patent: June 7, 1977
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Jurgen Rochlitz, Reinhard Zunker
  • Patent number: 4026704
    Abstract: This invention relates to an electrophotographic recording material comprising an electrically conducting carrier and a photoconducting laminate thereon, the latter comprising a base layer and a top layer each containing an organic photoconductor, binder and sensitizer, at least one organic photoconductor being common to both of said top and base layers and the base layer containing a bisazo dyestuff.
    Type: Grant
    Filed: August 12, 1975
    Date of Patent: May 31, 1977
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Jurgen Rochlitz, Richard Lehner
  • Patent number: 4025341
    Abstract: A photoconductive polymer, and photoconductive insulating compositions and elements containing the same, are disclosed. The aforementioned polymer is a condensation product, preferably of relatively low molecular weight, of certain tertiary aromatic amines and certain carbonyl-containing compounds.
    Type: Grant
    Filed: December 20, 1974
    Date of Patent: May 24, 1977
    Assignee: Eastman Kodak Company
    Inventor: Norman G. Rule
  • Patent number: 4025340
    Abstract: Toning an electrophotographic layer by adding materials which bleach at different rates, and thereafter selectively bleaching the materials after development.
    Type: Grant
    Filed: November 10, 1971
    Date of Patent: May 24, 1977
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masaaki Takimoto, Satoru Honjo
  • Patent number: 4018602
    Abstract: Method for in situ preparation of photoconductive composite having an electronically active hole transport layer, an electronically active electron transport layer and a layer of charge transfer complex sandwiched therebetween. According to this method, a film containing either an electron donor or an electron acceptor is initially formed directly on a supportive (preferably conductive) substrate. After this film has been allowed to set, a second film is solvent coated on the previously formed film. The solvent used in preparation of the second film causes softening of the previously formed layer which permits interaction of an electron acceptor or an electronic donor in the casting solvent with an electron acceptor or an electron donor of the previously formed layer, thereby forming a charge transfer complex at the interface of these two films. Only a portion of the donor and acceptor interact along this common boundary during the formation of the photoconductive composite.
    Type: Grant
    Filed: April 17, 1975
    Date of Patent: April 19, 1977
    Assignee: Xerox Corporation
    Inventor: Joseph Y. C. Chu
  • Patent number: 4018607
    Abstract: A specific class of crystalline organic pigments having the formula ##STR1## WHEREIN N IS 1 OR 2; X consists of the atoms necessary to complete a naphthalene, anthracene, or ##STR2## R.sup.1, R.sup.2, and R.sup.3 are independently selected from the group consisting of hydrogen, halogen, alkoxy, NO.sub.2, alkyl, SO.sub.3 H or alkali metal salts thereof, and COOH or alkali metal salts thereof; and wherein R.sup.2 and R.sup.3 can comprise the atoms necessary to complete a phenyl, naphthyl or anthryl ring; and R is selected from the group consisting of ##STR3## or COOM wherein M is alkyl or an alkali or alkaline earth metal is useful as sensitizers for photoconductive compositions in electrophotographic processes.
    Type: Grant
    Filed: May 3, 1974
    Date of Patent: April 19, 1977
    Assignee: Eastman Kodak Company
    Inventor: Lawrence E. Contois
  • Patent number: 4018606
    Abstract: A class of organic pigments having the formula ##STR1## wherein X consists of the atoms necessary to complete a naphthalene, anthracene, or ##STR2## ring; R.sup.1, R.sup.2, and R.sup.3 are hydrogen, halogen, alkoxy, NO.sub.2, alkyl, SO.sub.3 H or alkali metal salts thereof, ##STR3## and COOH or alkali metal salts thereof, and R.sup.2 and R.sup.3 can comprise the atoms necessary to complete a phenyl, naphthyl or anthryl ring; and R is selected from the group consisting of ##STR4## where M is alkyl, alkali or alkaline earth metal are useful as sensitizers for photoconductive compositions in electrophotographic processes.
    Type: Grant
    Filed: May 3, 1974
    Date of Patent: April 19, 1977
    Assignee: Eastman Kodak Company
    Inventors: Lawrence E. Contois, Joseph Y. Kaukeinen, Stephen Michel, Thomas M. Plutchak
  • Patent number: 3999989
    Abstract: A photosensitizer for electrophotographic photosensitive materials comprising inorganic or organic acid salts of indoline spirobenzopyranes of the formula ##STR1## R.sub.1, R hd 2, R.sub.3, X and Y are defined in the specification.
    Type: Grant
    Filed: January 25, 1974
    Date of Patent: December 28, 1976
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hisatake Ono, Syu Watarai, Chiaki Osada
  • Patent number: 3998636
    Abstract: A recording material suited for the photographic production of a conductivity pattern, wherein said material contains a recording layer applied to the surface of a support the surface resistance of which is at least 100 times as small as that of the recording layer and wherein said recording layer contains in intimate admixture:I. at least one ultraviolet radiation-sensitive organic polyhalogen compound from which photolytically halogen-containing free radicals can be separated,Ii. a photoconductive polymer containing N-vinylcarbazole units andIii. as sensitizing agent increasing the conductivity of the recording layer during its photo-exposure an acylamino compound corresponding to the following general formula:R.sub.1 -- CO -- NH -- R.sub.2wherein:R.sub.1 represents an alkyl group or a cycloalkyl group, andR.sub.2 represents an aromatic group.
    Type: Grant
    Filed: February 21, 1975
    Date of Patent: December 21, 1976
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Jozef Willy Van den Houte, Yvan Karel Gilliams, Pierre Richard De Roo
  • Patent number: 3997342
    Abstract: A photoconductive element having at least two layers, namely a charge-generation layer and a charge transport layer, is disclosed. The charge-generation layer contains a finely divided co-crystalline complex of (i) at least one polymer having an alkylidene diarylene group in a recurring unit and (ii) at least one pyrylium-type dye salt. The charge transport layer contains an organic photoconductive charge transport material exhibiting both kinetic and thermodynamic stability. Either one or both of the charge-generation and charge-transport layers of the element also contains a protonic acid material. The resultant photoconductive element exhibits persistent conductivity.
    Type: Grant
    Filed: October 8, 1975
    Date of Patent: December 14, 1976
    Assignee: Eastman Kodak Company
    Inventor: David S. Bailey
  • Patent number: 3996049
    Abstract: This invention relates to: an electrophotographic recording material consisting of an electroconductive support material and a photoconductive double layer of organic materials which consists of a homogeneous, opaque, charge carrier producing dyestuff layer of a compound corresponding to the general formula ##STR1## WHEREIN M IS 0 OR 1,n is 1 or 2,X is oxygen or imino nitrogen (=N-),R.sub.1 and R.sub.3 which may be the same or different, are hydrogen, an alkyl group with 1 to 4 carbon atoms, an anthra-quinone or benzanthrone group, or --CO--NH--R.sub.5, with R.sub.5 being an anthraquinone group,R.sub.2 and R.sub.4, which may be the same or different, are hydrogen or a single bond directed to the position of a radical in R.sub.1 or R.sub.3, or a single bond which, together with the imino nitrogen, forms part of a pyrazole or pyrimidine ring, andR.sub.1 and R.sub.
    Type: Grant
    Filed: May 15, 1975
    Date of Patent: December 7, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Jurgen Rochlitz
  • Patent number: 3994724
    Abstract: An electrophotographic element comprised of a slightly conductive support and an insulating coating thereon comprised of an insulating resin and a substituted aniline photoconductor. An electron acceptor sensitizing agent can also be added to the insulating coating.
    Type: Grant
    Filed: July 23, 1969
    Date of Patent: November 30, 1976
    Assignee: Scott Paper Company
    Inventor: John Alan Mattor
  • Patent number: 3992205
    Abstract: This invention relates to electrophotographic recording material comprising an electrically conductive carrier material having thereon a photoconductive multi-layer system of a charge carrier producing dyestuff layer or organic material and an insulating, organic, covering layer thereon with at least one charge carrier transporting compound, said dyestuff layer comprising at least two pigment dyes absorbing in different spectral regions, i.e. in the region of relatively long waves and in the region of relatively short waves.
    Type: Grant
    Filed: October 22, 1974
    Date of Patent: November 16, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Wolfgang Wiedemann
  • Patent number: 3992203
    Abstract: Electrophotographic recording material is disclosed comprising at least one polyphenylenevinylene having a molecular weight greater than 2,000 g/mol and at least one 1,4-bis (styryl) benzene derivative.
    Type: Grant
    Filed: April 18, 1975
    Date of Patent: November 16, 1976
    Assignee: VEB Pentacon Dresden
    Inventors: Hans-Heinrich Horhold, Joachim Gottschaldt, Regina Bergmann, Johannes Opfermann, Walter Seliger, Siegfried Augst, Hartmut Arnstadt
  • Patent number: 3990898
    Abstract: The color speeds of a multicolor photosensitive element are balanced during the manufacture thereof by continuously introducing into said element optical filter means adapted to modulate the photographic color speed of at least one of the selectively sensitized silver halide emulsions relative to the other(s), and then adjusting the density of said optical filter means during coating to an amount sufficient to obtain the desired color balance.
    Type: Grant
    Filed: June 26, 1974
    Date of Patent: November 9, 1976
    Assignee: Polaroid Corporation
    Inventor: Edwin H. Land
  • Patent number: 3989520
    Abstract: This invention relates to an electrophotographic recording material consisting of an electroconductive support material and a photoconductive double layer of organic materials which consists of a homogeneous, opaque, charge carrier producing dyestuff layer and of a transparent top layer of insulating materials with at least one charge transporting compound.
    Type: Grant
    Filed: May 20, 1975
    Date of Patent: November 2, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Jurgen Rochlitz
  • Patent number: 3984378
    Abstract: Photoconductive, film forming nitropyrene-formaldehyde resins characterized by a repeating structural unit of the formula: ##SPC1##And process for preparation, the photoconductive films themselves, and such films on an electrically conductive support.
    Type: Grant
    Filed: March 12, 1974
    Date of Patent: October 5, 1976
    Assignee: Kabushiki Kaisha Ricoh
    Inventors: Tomio Kubota, Shoji Maruyama, Takao Igawa
  • Patent number: 3982937
    Abstract: This invention relates to an article which comprises an electrically conductive carrier layer, a layer comprising a material selected from the group consisting of selenium or selenium-tellurium, and, on the side of the selenium or selenium-tellurium layer remote from the carrier layer, a layer comprising an oligomeric condensation product of 3-bromopyrene and formaldehyde having a degree of polycondensation of 6 to 10.
    Type: Grant
    Filed: July 12, 1974
    Date of Patent: September 28, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Wolfgang Wiedemann
  • Patent number: 3982935
    Abstract: This disclosure relates to an electrophotographic copying process suitable for use in a multiple copying system. The process is characterized by use of an electrophotographic medium comprising photosensitive organic compounds which are either (1) insulating prior to irradiation and substantially permanently conductive subsequent to irradiation or (2) conductive prior to irradiation and substantially permanently insulating subsequent to irradiation. The process comprises the steps of exposing the electrophotographic medium to a pattern of activating radiation to produce a latent image with a conductivity pattern that is irreversible and permanently altered and externally applying an electrical charge at any suitable time thereby forming an electrostatic pattern which can be developed by any of the known electrophotographic developing techniques.
    Type: Grant
    Filed: August 1, 1974
    Date of Patent: September 28, 1976
    Assignee: Itek Corporation
    Inventors: Richard F. Bartlett, Laura K. Case
  • Patent number: 3982938
    Abstract: Improved toner particles each comprising an intimate mixture of a photoconductive pigment and an insulating binder capable of transporting charge carriers when the charge carriers are injected therein from the pigment, the proportion of the total volume of the pigment in the toner particle being 2 to 30 volume percent of the toner particle and the insulating binder being substantially transparent to the light in the region of the spectrum to which the pigment is sensitive. The toner particle may have therein a core or cores of a material which is substantially transparent to the light in the spectral-sensitive region of the pigment. The toner particles have improved surface durability and can be used repeatedly.
    Type: Grant
    Filed: February 12, 1974
    Date of Patent: September 28, 1976
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Satoru Honjo, Hajime Miyatuka, Seiji Matsumoto
  • Patent number: 3979394
    Abstract: New "duplo" quinoline compounds useful as photoconductors and having the formula: ##SPC1##Wherein:Z represents the atoms necessary to close an adjacent aromatic ring,R' represents a lower alkyl radical, andX represents an alkylene group or an alkylene group interrupted by a bivalent aromatic group.
    Type: Grant
    Filed: March 5, 1974
    Date of Patent: September 7, 1976
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Wilhelmus Janssens, Johannes Josephus Vanheertum, Albert Lucien Poot, Robert Joseph Pollet
  • Patent number: 3977870
    Abstract: The present invention relates to an electrophotographic recording material consisting of an electroconductive support material with a photoconductive double layer of organic materials which consists of a homogeneous, opaque, charge carrier producing dyestuff layer and of a transparent top layer of insulating materials containing at least one charge transporting compound, which is characterized in that the organic dyestuff layer consists of a compound of the general formula ##EQU1## wherein --A-- is a diphenyl or azobenzene group which may be substituted by alkyl with 1 to 4 carbon atoms, alkoxy with 1 to 4 carbon atoms, and/or halogen,R and R.sub.1, which may be the same or different, are alkyl with 1 to 4 carbon atoms or carbalkoxyl, in which the alkyl groups have from 1 to 4 carbon atoms, andR.sub.2 and R.sub.3 are phenyl groups which may be substituted by alkyl with 1 to 4 carbon atoms.
    Type: Grant
    Filed: May 29, 1975
    Date of Patent: August 31, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Jurgen Rochlitz
  • Patent number: 3974147
    Abstract: Dihydroheterocyclic amines having a N-hydrocarbyl substitution and a 2-(or 4-) (omega-(nuclearly substituted cyclic)) vinylenyl substitution are described. There compounds are oxidized in an acidic environment to produce styryl dyes.
    Type: Grant
    Filed: June 25, 1975
    Date of Patent: August 10, 1976
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: George V. D. Tiers, Joseph A. Wiese, Jr.
  • Patent number: 3973959
    Abstract: This invention relates to an electrophotographic recording material consisting of an electroconductive support material and a photoconductive double layer of organic materials which consists of a homogeneous, opaque, charge carrier producing dyestuff layer and of a transparent top layer of insulating materials with at least one charge transporting compound as well as to the process for its manufacture.
    Type: Grant
    Filed: April 25, 1973
    Date of Patent: August 10, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Jurgen Rochlitz, Wolfgang Wiedemann
  • Patent number: 3973962
    Abstract: An aggregate or heterogeneous multiphase photoconductive composition containing a continuous polymer phase and at least one discontinuous phase dispersed in said continuous phase, said discontinuous phase comprising a co-crystalline complex of (i) at least one polymer having an alkylidene diarylene group in a recurring unit (ii) at least one pyrylium type dye salt having a non-light absorbing anion, and (iii) at least one pyrylium type dye salt having a colored organic or organo-metallic anion of a strong acid.
    Type: Grant
    Filed: May 2, 1974
    Date of Patent: August 10, 1976
    Assignee: Eastman Kodak Company
    Inventors: Lawrence E. Contois, Norman G. Rule, William J. Staudenmayer
  • Patent number: RE29554
    Abstract: Organic photoconductive systems which employ organic polymers containing aromatic or heterocyclic nuclei are combined with amounts of .pi. acid type additives for the purpose of extending the spectral response to the visible portion of the spectrum. The sensitizing compounds are dicyanomethylene substituted fluorenes which are added in an amount expressed in moles of sensitizer per 100 moles of the organic photoconductor calculated as the monomer. The amount of sensitizer to be added may range from 0.1 to about 100 moles per 100 moles of organic photoconductor based on the molecular weight of the monomer.
    Type: Grant
    Filed: April 1, 1976
    Date of Patent: February 28, 1978
    Assignee: Addressograph-Multigraph Corporation
    Inventor: Evan S. Baltazzi