Abstract: An electrophotographic recording medium which consists essentially of an electrically conductive base and a photosemiconductive double layer which comprises a first layer containing charge carrier-producing dyes, and a second layer containing one or more compounds which are charge carrier-transporting when exposed to light, wherein the charge carrier-producing dyes are those of the general formula I ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are each hydrogen, halogen, alkyl, nitro or cyano, R.sup.4 is phenyl, halophenyl, alkylphenyl, nitrophenyl or dialkylaminophenyl, and X is oxygen, sulfur, NH or N-phenyl, and the production of this recording medium.
Type:
Grant
Filed:
March 16, 1982
Date of Patent:
August 2, 1983
Assignee:
BASF Aktiengesellschaft
Inventors:
Manfred Dimmler, Gerhard Hoffmann, Dieter Buhl
Abstract: This specification discloses a method of toner transfer development in which a low frequency alternating electrical bias is applied to the space between a latent image bearing member and a developer carrying member to develop the latent image on the latent image bearing member, and an apparatus for carrying out the same method. This bias has a first process in which reciprocal movement of developer particles is effected also between the non-image area of the latent image bearing member and the developer carrying member, and a second process in which the intensity of the bias is adjusted so that one-sided movement of developer particles from the developer carrying member to the image area and one-sided movement of developer particles from the non-image area to the developer carrying member may take place.
Abstract: In an electrophotographic photosensitive member having a photoconductive layer composed of a photoconductive material and a binder, improvement wherein said binder is a curable rubber.
Abstract: A photoconductive member comprise a support, a photoconductive layer constituted of an amorphous material containing silicon atoms as matrix and containing hydrogen atoms or halogen atoms, and an intermediate layer provided between them, said intermediate layer having a function to bar penetration of carriers from the side of the support into the photoconductive layer and to permit passage from the photoconductive layer to the support of photocarriers generated in the photoconductive layer by projection of electromagnetic waves and movement of the photocarriers toward the side of the support, and said intermediate layer being constituted of an amorphous material containing silicon atoms and carbon atoms as constituents.
Abstract: An electrophotographic sensitizing screen having a great number of apertures, wherein at least an insulating layer and a conductive layer are successively formed on a conductive mesh, is disclosed. These apertures are regularly arranged at such an angle as not to produce moire fringes with respect to a light image projected on the screen.
Abstract: This invention is directed to a process and apparatus for causing the development of electrostatic latent images, the process comprising providing a development zone encompassed by a tensioned deflected flexible imaging member and a transporting member, causing the deflected flexible imaging member to move at a speed of from about 5 cm/sec to about 50 cm/sec, causing the transporting member to move at a speed of from about 6 cm/sec to about 100 cm/sec, said deflected flexible imaging member and said transporting member moving at different speeds, maintaining a distance between the flexible imaging member and the transporting member of from about 0.05 millimeters to about 1.
Abstract: A photoconductive member comprises a support, a photoconductive layer constituted of an amorphous material containing silicon atoms as matrix and containing hydrogen atoms or halogen atoms, and an intermediate layer provided between them, said intermediate layer having a function to bar penetration of carriers from the side of the support into the photoconductive layer and to permit passage from the photoconductive layer to the support of photocarriers generated in the photoconductive layer by projection of electromagnetic waves and movement of the photocarriers toward the side of the support, and said intermediate layer being constituted of an amorphous material containing silicon atoms and carbon atoms a constituents.
Abstract: In an electrostatic photographic process comprising subjecting an electrostatic photographic photosensitive plate to the combination of negative charging, positive charging and imagewise exposure to form an electrostatic latent image of a positive polarity, said electrostatic photographic photosensitive plate having such charging characteristics that a photosensitive layer can be positively charged by sequential negative corona charging and positive corona charging and positive charging is rendered substantially impossible by irradiation with light, and then subjecting the so treated photosensitive plate to positive charging a predetermined number of times, whereby an electrostatic latent image is formed the predetermined number of times by imagewise exposure conducted once, if a zinc oxide-resin dispersion is used for the photosensitive layer of the photosensitive plate and predetermined amounts of a triphenylmethane basic dye and a silicone oil are incorporated in the photosensitive layer, the time required
Abstract: This invention is directed to developer compositions comprised of toner particles and carrier particles, the toner particles being comprised of resin particles, pigment particles, and from about 0.1 to about 10 percent based on the weight of the toner particles of an alkyl pyridinium toluene sulfonate charge enhancing additive of the formula: ##STR1## wherein R is an alkyl radical containing from about 12 carbon atoms to about 25 carbon atoms, which compositions are useful for causing the development of images in electrostatographic imaging systems.
Abstract: An electrophotographic photosensitive member having a photosensitive layer is characterized in that said photosensitive layer contains azo pigments having at least one of azo groups linked to a coupler residue represented by the following formula [1] or [2]: ##STR1## wherein R.sub.1 and R.sub.3 independently represent hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted aralkyl, or substituted or unsubstituted aryl, and R.sub.2 and R.sub.4 independently represent substituted or unsubstituted aryl.
Abstract: An electrophotographic recording material comprising an electrically conductive support, an optional insulating intermediate layer, at least one photoconductive layer comprising a charge carrier generating compound and a charge transporting compound, and a protective transparent cover layer made from a surface abrasion resistant binder composed of a polyurethane resin, polycarbonate resin, phenoxy resin, polyacrylate or polymethacrylate resin, polyurethane formed from a two-component system comprising a polyisocyanate and a hydroxyl group containing polyester or polyether, a polyisocyanate and a hydroxyl group containing acrylic or epoxy resin, polyurethane formed from a one-component system comprising a polyisocyanate prepolymer, or a polyisocyanate having temporarily masked isocyanate groups.
Abstract: A photoconductive composition comprising a photoconductive substance and a thiobarbituric acid derivative, and an electrophotographic light-sensitive medium comprising a support having a layer of the photoconductive composition thereon.
Type:
Grant
Filed:
April 21, 1981
Date of Patent:
June 21, 1983
Assignee:
Fuji Photo Film Co., Ltd.
Inventors:
Syunichi Kondo, Hirotsugu Nomaguchi, Hideo Sato
Abstract: A liquid developer for use in electrophotography is disclosed which is prepared by dispersing a toner consisting essentially of a pigment or dye and a resin in a carrier liquid having a high insulating property and a low dielectric constant, wherein said resin is a nonaqueous dispersed resin obtained by effecting, in a nonaqueous solvent comprising an aliphatic hydrocarbon, the steps of:(a) copolymerizing (1) a monomer A having the general formula I: ##STR1## [wherein R is H or --CH.sub.3, and A is --COOC.sub.n H.sub.2n+1 or --OC.sub.n H.sub.
Abstract: Disclosed is a process for manufacturing a lithographic printing form by electrophotographic means, comprising the steps of uniformly charging an oleophilic photoconductive layer which is present on an electrically conductive hydrophilic layer support and which contains a photoconductor and a binder; image-wise exposing the charged photoconductive layer to produce a charge image; developing the charge image with toner to produce a toner image comprised of imaged areas and non-image areas; fixing the toner image; decoating the non-image areas of the photoconductive layer to bare the electrically conductive layer support; coating the bared areas of the layer support with a solution comprising a water-soluble, but hydrocarbon-insoluble film-forming polymer and a vinyl phosphonic acid compound; drying the coating solution to form a uniform coating; and removing the toner image by rinsing with a hydrocarbon composition containing aromatic portions in an amount of at least about 20% by weight.
Abstract: A novel hydrazone compound having the following general formula I is disclosed, along with, a manufacturing process for same and a layered electrophotographic element comprising, in successive layers, an electrically conductive substrate, a charge carrier generating layer and a charge transfer layer containing said hydrazone compound: ##STR1## (wherein R is hydrogen, an alkyl group, an alkoxy group or a dialkylamino group, and n is an integer of 1 to 3.
Abstract: A developing device for electrophotography includes a developer supporter faced to an image bearing member with a constant space maintained therebetween, a magnetic field generator for limiting the thickness of developer on the developer supporter. An element is provided within the magnetic field generated by the generator and in the vicinity of the developer supporter to limit the thickness of developer which is rendered erect by the magnetic field. The element is effective to limit the thickness of developer supported on the supporter to a value not causing contact of the developer with the non-imaged area on the image bearing member.
Abstract: In an electrophotographic photosensitive material comprising an electroconductive substrate having positioned thereon a photosensitive layer comprising as main components titanium dioxide and a binding material, the photosensitivity and whiteness can be improved by allowing a specific cyanine dye compound to exist in said photosensitive layer.
Abstract: The present invention provides a novel hydrazone compound expressed by the general formula I ##STR1## (wherein Ar represents substituted or non-substituted naphthyl group, anthryl group, styryl group, pyridyl group, thienyl group, furyl group or carbazolyl group.);the process for manufacturing thereof; and a multilayer type electrophotographic element comprising an electrically conductive substrate and a charge carrier generating layer and a charge transfer layer as successively superposed on said substrate, said charge transfer layer containing a hydrazone compound, as effective ingredient, expressed by the general formula II ##STR2## (wherien Ar' represents condensed polycyclic rings such as substituted or non-substituted naphthalene ring, anthracene ring and the like; heterocyclic rings such as substituted or non-substituted furan ring, thiophene ring, pyridine ring, carbazole ring and the like; or substituted or non-substituted styryl group.
Abstract: A photoconductive layer sensitized by a compound of the general formula: ##STR1## in which: R.sup.1 and R.sup.2 independently represent a hydrogen atom, an alkyl or substituted alkyl group, an aryl or substituted aryl group, an aralkyl or substituted aralkyl group, a cycloaliphatic or substituted cycloaliphatic group or a heterocyclic or substituted heterocyclic group providing R.sup.1 and R.sup.2 do not both represent cyclic groups of aromatic nature, or R.sup.1 and R.sup.2 together may represent the necessary atoms to complete a non-aromatic heterocyclic ring,R.sup.3, R.sup.4, R.sup.5 and R.sup.6 independently represent a hydrogen atom or any substituent providing the sum of their .sigma..sub.p constants has a value of less than +0.5, or R.sup.3 and R.sup.4 and/or R.sup.5 and R.sup.6 may represent the necessary atoms to complete an alicyclic or aromatic ring, R.sup.3 and R.sup.2 and/or R.sup.1 and R.sup.6 may represent the necessary atoms to complete a non-aromatic heterocyclic ring,R.sup.7 and R.sup.
Type:
Grant
Filed:
February 27, 1981
Date of Patent:
May 17, 1983
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A photographic member includes an electrically conductive substrate which carries a pair of photoconductive layers thereon, which are charged to opposite polarities from each other, as will be further defined herein. The photosensitive member has a surface potential which is of either positive or negative polarity. Subsequently, the photosensitive member is imagewise exposed to light image formed by light of a wavelength which principally renders only one of the photoconductive layers conductive. Areas of the photosensitive member which are irradiated by the light radiation during the imagewise exposure is subjected to a line scanning by a light spot having an extremely small diameter and of a wavelength which principally renders the other conductive layer conductive either simultaneously with or after the imagewise exposure. The spot has a reference light intensity, which is modulated by a pair of write signals.