Abstract: The invention involves a method for making one component or single component toner compositions for developing electrophotographic images. A binding component is mixed with magnetic particles, pulverized, then carbon black is mixed with the powder and fixed to the surface of the particles. Compositions having a measured resistivity of 4.3.times.10.sup.3 to 4.3.times.10.sup.6 ohm-cm at a D.C. field of below 20 volts/cm under substantially no-load conditions are selected for use.
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, R.sup.3 and R.sup.4 are each hydrogen or a non-ionic substituent, X and Y are each the radical of a methylene-active compound, or of an aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic amine or hydrazine, and Z is hydrogen, methyl or phenyl, and the production of this recording medium.
Type:
Grant
Filed:
November 22, 1983
Date of Patent:
November 6, 1984
Assignee:
BASF Aktiengesellschaft
Inventors:
Albrecht Eckell, Heinz Eilingsfeld, Albert Elzer, Franz Feichtmayr, Gerhard Hoffmann, Reinhold J. Leyrer, Peter Neumann
Abstract: A layered electrophotographic photoconductor whose charge generation layer comprises a bisazo pigment selected from the group consisting of the bisazo pigments represented by the following general formula (I) and whose charge transport layer contains a charge transport material selected from the group consisting of the hydrazone compounds represented by the following general formula (2): ##STR1## wherein A represents --C.sub.6 H.sub.4 --Cl(o), --C.sub.6 H.sub.4 --Cl(m), --C.sub.6 H.sub.4 --Br(o), --C.sub.6 H.sub.4 --Br(m), --C.sub.6 H.sub.4 --F(o), --C.sub.6 H.sub.4 --F(m), --C.sub.6 H.sub.4 --F(p), or --C.sub.6 H.sub.4 --I(m), ##STR2## wherein R.sup.
Abstract: The surface properties of solid substrates are improved by the formation of discrete sites of inorganic materials on one surface of the substrate.
Type:
Grant
Filed:
February 3, 1982
Date of Patent:
November 6, 1984
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Vasant V. Kolpe, Dudley M. Sherman, William A. Hendrickson, Hsin-hsin Chou
Abstract: A method for developing an electrostatic latent image on a nonporous surface using a self-fixing liquid developer is described. The developer contains a volatile, electrically insulating carrier, and toner particles, dispersed in the carrier, containing a polymer binder which has a Tg within the range from about -10.degree. C. to 30.degree. C. Upon application of the developer to a latent image and evaporating the liquid carrier from the image, the toner particles fix to the surface without externally applied heat other than from ambient conditions.
Type:
Grant
Filed:
September 27, 1982
Date of Patent:
October 30, 1984
Assignee:
Eastman Kodak Company
Inventors:
Peter S. Alexandrovich, Stewart H. Merrill
Abstract: This invention is generally directed to an improved process for fixing developed electrostatic images which comprises (1) forming an electostatic latent image on an imaging member, (2) developing the image with a toner composition comprised of polyamide toner resin particles, and pigment particles, (3) transferring the developed image to a substrate, and (4) sequentially subjecting the transferred image to a cold pressure fixing source, and a radiant energy fixing source.
Abstract: A highly sensitive photoreceptor for electrophotography that forms a sharp image during repeated use is disclosed. It comprises an electrically conductive support having successively formed thereon a photoconductive photosensitive layer and a protective layer for that photosensitive layer, said photosensitive layer comprising an organic photoconductive material and said protective layer comprising an amorphous silicon carbide or amorphous silicon nitride containing a hydrogen atom and/or a fluorine atom. A method of forming a latent electrostatic image and an electrophotographic process using such photoreceptor are also disclosed.
Abstract: A method and an apparatus for transferring a toner image in a transfer zone from a photoconductor to an image carrier 15. The photoconductor is mounted on an upper part 65 of a travelling table 3. The image carrier 15 lies on an inclined feed table, and after the image carrier has been released, it is held on a transport cylinder 17 by means of gripper mechanisms and is urged against the transport cylinder by a first pressure mechanism. A second pivoting pressure mechanism and the transport cylinder convey the image carrier to a third gripper mechanism, which is displaced parallel to an inclined deposit to guide the image carrier in an upward direction via a fixing station and is then opened so that the image carrier drops into the deposit.
Type:
Grant
Filed:
November 12, 1982
Date of Patent:
October 9, 1984
Assignee:
Hoechst Aktiengesellschaft
Inventors:
Hermann Idstein, Dieter Silbereisen, Hermann Reininger
Abstract: An improved apparatus for the preparation of photopolymerized relief image plates is disclosed in which a series of indicators are used to indicate that the liquid photopolymerizable material is prepared for exposure to actinic radiation. Such detection may be accomplished by the closure of electrically energized indicator circuits used to detect when a top cover is in position over a layer of liquid photopolymerizable material. In addition, the actinic radiation may be activated directly by the closure of such circuits. Also disclosed is a method by which the time required for the top cover to come to rest in position over the photopolymerizable layer can be measured, and this measurement may then be used as a control to determine if a sufficient amount of photopolymerizable material to make an acceptable relief image plate was deposited on the platemaking surface.
Abstract: Improved electrographic development is obtained in the presence of a development electrode field by predeterminedly rotating both the core and shell of a magnetic brush applicator to supply developer, of the kind comprising small particle, hard-magnetic carrier and electrically insulative toner, to an electrostatic imaging member which moves past a development station with predetermined linear velocity. In one preferred embodiment the core and shell are predeterminedly rotated so that the shell moves through the development zone at a rate preventing toner that is plated-out on the shell from affecting image development and so that the developer moves co-currently with the imaging member at a generally equal linear velocity.
Type:
Grant
Filed:
July 1, 1983
Date of Patent:
September 25, 1984
Assignee:
Eastman Kodak Company
Inventors:
Garold F. Fritz, George P. Kasper, Arthur S. Kroll, Michael Mosehauer
Abstract: An electrophotographic recording material comprised of an electrically conductive support, an optional insulating interlayer, a photoconductive system comprised of at least one layer of organic material containing a charge carrier-producing compound and a charge-transporting compound, and a radiation-cured, transparent protective layer, wherein the protective layer has been applied onto the surface of the photoconductive system with the aid of a removable auxiliary support and is comprised of an acrylated binder which is cured by irradiation with ultraviolet light. Also disclosed is a process for the production of the recording material.
Abstract: Disclosed is a photosensitive material for the electrophotography, which comprises a dispersion of a charge-generating pigment in a charge-transporting medium composed mainly of a polyvinyl carbazole resin, wherein a perylene pigment represented by the following general formula: ##STR1## wherein R.sub.1 and R.sub.2 stand for a hydrogen atom or a substituted or unsubstituted alkyl or aryl group, is dispersed and incorporated as the charge-generating pigment in an amount of 1 to 40 parts by weight per 100 parts by weight of the polyvinyl carbazole resin and a halogeno-p-benzoquinone is further incorporated in an amount of 1 to 60 parts by weight per 100 parts by weight of the polyvinyl carbazole resin.
Abstract: Photoconductive compositions and elements comprising arylalkane photoconductors and pyrylium sensitizers are stabilized against adverse leuco base color shifts into the ultraviolet to blue spectral region by the incorporation of certain 1,4,5,8-naphthalene bis-dicarboximide compounds. The compositions and elements are particularly suited for electrophotographic image formation and thereafter for contact printing of the image onto sensitive material by ultraviolet or blue transmission through the composition or element.
Abstract: An article in web or sheet form, especially useful in the packaging or container art, having control indicia. The indicia are detectable under special conditions for controlling operations in the manufacture and/or use of the article. In the preferred embodiment the indicia are invisible and of a polar or ionic organic material that will not significantly migrate through a plastic web. The indicia emit electromagnetic wavelength-shifted radiation in response to incident electromagnetic radiation of a selected wavelength.
Abstract: An improved layered photoresponsive imaging device consisting of(1) a supporting substrate,(2) a photogenerating layer comprised of a charge carrier photogenerating pigment dispersed in a resinous binder,(3) a hole carrier transport layer, comprised of molecules of the formula ##STR1## dispersed in a highly insulating and transparent organic resinous material, wherein an X is selected from the group consisting of (ortho) CH.sub.3, (meta) CH.sub.3, (para) CH.sub.3, (ortho) Cl, (meta) Cl, (para) Cl, and a hole injecting electrode strip comprised of carbon black particles and graphite particles dispersed in a resinous binder, which strip is attached to and extends the length of the non-image areas of the hole carrier transport layer.
Abstract: An electrostatographic toner material suitably employable for the pressure fixing process, which comprises encapsulated toner particles having an average particle size in the range from about 0.5 to 1,000 microns, in which the toner particle comprises a pressure fixable adhesive core material containing a colorant and a curable substance and a pressure rupturable shell enclosing the core material, the outer surface of the shell being provided with a curing agent capable of curing said curable substance.The curable substance and the curing agent can be separately incorporated into the core materials of the different encapsulated toner particles.
Abstract: A water fixable toner powder is provided for making powder images that can be transferred and fixed with good image quality onto receiving material such as paper by being covered with water, squeegeed and subsequently pressed against the receiving material. The individual particles of the toner powder consist essentially of hydrolyzed polyvinyl ester that is swellable but insoluble in water at a temperature up to 30.degree. C., such preferably as polyvinyl alcohol having a degree of hydroylsis above 98% and an average molecular weight of at least 4,000, together with finely divided filler material that is insoluble and non-swellable in water and is present in an amount of between 10 and 60% by volume. Other additives such as coloring material and/or a polarity control agent may also be present in the binder of hydrolyzed polyvinyl ester. Preferred forms of the toner particles are porous and have a specific surface of between 0.6 and 2m.sup.2 /g.
Type:
Grant
Filed:
October 22, 1982
Date of Patent:
August 14, 1984
Inventors:
Nicolaas P. J. Kuin, Jozef J. A. Pleyers
Abstract: A method for amplifying an electrostatic, charge-differential pattern is disclosed. The method comprises (a) imagewise forming a first toner deposit by developing a first electrostatic pattern having a first charge differential per unit area whose maximum value is no greater than a preselected level, (b) in an image-amplification element comprising a charge-holding surface layer overlying a field-supporting electrode, forming a current-carrying path between the toner deposit and the field-supporting electrode, (c) under conditions in which nontoned regions are not photoexcited, overall charging the image-amplification element with sufficient charge to form an enhanced electrostatic charge pattern having a second charge differential per unit area whose maximum value is greater than the preselected value in step (a), and (d) developing the enhanced charge pattern into a second toner deposit.
Abstract: An electrophotographic light-sensitive material is disclosed. The material is comprised of a conductive layer containing cuprous iodide and a photoconductive layer. The photoconductive and electrophotographic characteristics are improved by forming a gelatin interlayer between the conductive layer and the photoconductive layer. The electrophotographic light-sensitive material can be used with either positive polarity or negative polarity.
Abstract: A photoconductive film comprising a photo-conductive layer which is mainly made of selenium and a region added with tellurium in a direction of the thickness of the layer, wherein at least either one of a portion in a direction of hole flow of said region added with tellurium and a portion in the hole flow of another region which is located adjacent to said region added with tellurium is doped with at least one member selected from the group consisting of an oxide, a fluoride and elements which belong to the group II, III and VII, which are capable of forming a negative space charge in selenium, at a concentration in a range of 10 ppm to 1% by weight on an average. Typical examples of such oxide, fluoride and element include CuO, In.sub.2 O.sub.3, SeO.sub.2, V.sub.2 O.sub.5, MoO.sub.3, WO.sub.3, GaF.sub.2 InF.sub.3, Zn, Ga, In, Cl, I, Br and the like. The after image characteristic ascribable to incident light of high intensity can be significantly improved.