Abstract: Controlled sensitivity of a photoconductor is obtained employing both type I and type IV titanyl phthalocyanine in a charge generation layer. The type I titanyl phthalocyanine is preferably premilled before milling the mixture.

Abstract: An electrophotographic imaging member with a charge generation section having separate layers of benzimidazole perylene photoconductive pigment and hydroxygallium ptalocyanine photoconductive pigment.

Abstract: The present invention relates to an electrophotosensitive material comprising a conductive substrate and a photosensitive layer formed on the substrate, the photosensitive layer containing a maleimide derivative represented by the general formula (1): wherein R represents hydrogen atom, alkyl, aryl or aralkyl. The electrophotosensitive material has high sensitivity, since maleimide derivative (1) has excellent electron acceptability, comparability with binder resin and matching with electric charge generating material.

Abstract: An electrophotographic photoconductor includes a conductive substrate and a photosensitive layer formed on a substrate. The photosensitive layer includes a phthalocyanine compound as a charge generation substance. An embodiment of the photosensitive layer contains a first phthalocyanine compound as a main component and a second phthalocyanine compound as a secondary component and as a result, has greater ability to generate negative charges than the ability of the first phthalocyanine compound.

Abstract: An electrophotography photosensitive body has a single layer photosensitive layer on top of a conductive substrate, directly or via an undercoat layer. The single layer photosensitive layer contains at least a resin binder, a charge generating substance, and a charge transport substance, wherein at least one of the charge generating substances is a titanyl phthalocyanine, which, in a x-ray powder diffraction spectrum having a radiation source of CuK &agr; and within a range of a Bragg angle 2 &thgr;=5˜35°, a ratio, R, of a value, P, of a diffraction intensity of a highest peak and a value, B, of a diffraction intensity of the background satisfies the equation R=(P−B)/B≦7.0. The resulting electrophotographic photosensitive layer shows excellent electrical properties with positive charging as well as excellent stability when repeatedly used.

Abstract: An image-forming apparatus comprising at least a photoreceptor, a toner and an exposure device, wherein the photoreceptor has a photosensitive layer containing oxytitanium phthalocyanine having a distinct diffraction peak at a Bragg angle (2&thgr;±0.2) of 27.3° in the X-ray diffraction by CuK&agr;-ray, and the toner has a volume average particle diameter (Dv) of from 3 to 8 &mgr;m and satisfies a relation of 1.0≦Dv/Dn≦1.3 where Dv is the volume average particle diameter and Dn is the number average particle diameter.

Abstract: An electrophotographic photosensitive member exhibiting a high sensitivity and a potential stability on repetitive use and capable of suppressing image defects, such as black spots in a reversal development scheme, is provided. The photosensitive member includes a support, and a phthalocyanine layer formed on the support and a novel phthalocyanine crystal, which comprises a phthalocyanine compound and a substituted or unsubstituted condensed polycyclic hydrocarbon compound.

Abstract: A photoconductive imaging member containing a photogenerating layer comprised of a mixture of perylenes, wherein the mixture comprises, for example, (1) 1,3-bis(n-pentylimidoperyleneimido) propane (Formula A), 1,3-bis(2-methylbutylimido peryleneimido)propane (Formula B) and 1-(n-pentylimidoperyleneimido)-3-(2-methylbutyl imidoperyleneimido)-propane (Formula C), and (2) an electron acceptor component polymer

Abstract: A mixture is made of a plurality of different titanyltetraazaporphyrin compounds, each of which is represented by formula (1): wherein A, B, C and D are each independently an unsubstituted or substituted benzene ring or pyridine ring, a substituent thereof being selected from the group consisting of nitro group, cyano group, a halogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxyl group having 1 to 8 carbon atoms, and an aryl group. The above-mentioned mixture is contained in a photoconductive layer of an electrophotographic photoconductor as a photoconductive material.

Abstract: An electrophotographic photosensitive body has a photosensitive layer formed on a conductive substrate. The photosensitive layer contains a phthalocyanine compound as a photoconductive material, wherein the content of a phthalocyanine dimer compound in the layer that contains the phthalocyanine compound is present from about 100 mmol to about 300 mmol per 1 mol of the phthalocyanine compound. The resulting electrophotographic photosensitive body has excellent potential retention properties.

Abstract: A photoconductive imaging member comprised of a mixture of at least two symmetrical perylene bisimide dimers of Formula 1 Formula 1 wherein R is hydrogen, alkyl, cycloalkyl, substituted alkyl, aryl, substituted aryl, aralkyl or substituted aralkyl, and at least one terminally unsymmetrical dimer of Formula 2 Formula 2 wherein R1 and R2 are hydrogen, alkyl, cycloalkyl, substituted alkyl, aryl, substituted aryl, aralkyl, or substituted aralkyl, and wherein R1 and R2 are dissimilar.

Abstract: Iodogallium phthalocyanine and bromogallium phthalocyanine having novel crystalline forms characterized by X-ray diffraction patterns according to CuK&agr; characteristic X-ray diffraction method and exhibiting excellent zirconium phthalocyanine can be obtained through appropriate selection of a reaction solvent, followed by milling or stirring in an appropriate solvent. For example, &agr;-chloronaphthalene is a suitable solvent for reaction between phthalonitrile and gallium triiodide or tribromide to provide iodogallium phthalocyanine or bromogallium phthalocyanine. Reaction of chlorogallium phthalocyanine or hydroxygallium phthalocyanine with hydroiodic (or hydrobromic) acid is also effective for providing a novel crystal form of iodo-(or bromo-)gallium phthalocyanine. Zirconium phthalocyanine exhibiting good electrophotographic performances can be obtained through a similar process.

Abstract: A photoreceptor including an electroconductive substrate and a photosensitive layer which is formed on the electroconductive substrate and which includes a charge generation material, wherein the charge generation material comprises an organic pigment and wherein the photosensitive layer further includes at least one ion selected from the group consisting of K+, Na+, NO3−, HCOO−, NO2−, Cl−, Br−, and NH4+ or one or more water-soluble inorganic salts.

Abstract: Compounds of the formula (I) in which the substituents are as defined in claim 1 are valuable colorants for the mass coloring of polymers, with fluorescence property, in electrophotographics toners and developers, in powders coating materials and ink-jet inks.

Abstract: An electrophotographic photosensitive member comprising a support and a photosensitive layer. The photosensitive layer contains an oxytitanium phthalocyanine having the strongest peak at 27.2°±0.2° of the diffraction angle (2&thgr;) in CuK&agr; characteristic X-ray diffraction and a hydroxygallium phthalocyanine having strong peaks at 7.4°±0.2° and 28.2°±0.2° of the diffraction angle (2&thgr;) in CuK&agr; characteristic X-ray diffraction. A process cartridge and an electrophotographic apparatus, employing the electrophotographic photosensitive member, are also disclosed.

Abstract: An electrophotographic photoreceptor is disclosed. The photoreceptor comprises pigment particles obtained by incorporating one or more metal atom into polycyclic anhydride-aromatic diamine condensation compound particles.

Abstract: A novel titanyl phthalocyanine crystal, a photoconductive material comprising the same, and an electrophotographic photoreceptor using the same are disclosed. The titanyl phthalocyanine crystal has a primary particle diameter ranging from 0.03 to 0.15 &mgr;m, shows a maximum X-ray diffraction peak at a Bragg angle (2&thgr;±0.2°) of 27.3°, has a ellipsoidal tabular form, and has a BET specific surface area of not less than 35 m2/g. The crystal has improved crystal form stability against solvents and holds its crystal form for an extended period of time in a dispersed and coated state. An electrophotographic photoreceptor using the crystal as a photoconductive material is excellent in sensitivity, stability, and durability.

Abstract: An electrophotographic photosensitive member is comprised of an aluminum substrate and a photosensitive layer provided thereon. The surface substrate on the side of the photosensitive member contains the elements aluminum, oxygen and titanium, or the elements aluminum, oxygen and zirconium. The photosensitive layer contains chlorogallium phthalocyanine, hydroxygallium phthalocyanine or oxytitanium phthalocyanine. The oxytitanium phthalocyanine has an intense peak at each of the Bragg's angles (2&thgr;G+0.2°) shown in any one of the specific five groups in CuK&agr;-characteristic X-ray diffraction.

Abstract: Iodogallium phthalocyanine and bromogallium phthalocyanine having novel crystalline forms characterized by X-ray diffraction patterns according to CuK&agr; characteristic X-ray diffraction method and exhibiting excellent zirconium phthalocyanine can be obtained through appropriate selection of a reaction solvent, followed by milling or stirring in an appropriate solvent. For example, &agr;-chloronaphthalene is a suitable solvent for reaction between phthalonitrile and gallium triiodide or tribromide to provide iodogallium phthalocyanine or bromogallium phthalocyanine. Reaction of chlorogallium phthalocyanine or hydroxygallium phthalocyanine with hydroiodic (or hydrobromic) acid is also effective for providing a novel crystal form of iodo- (or bromo-)gallium phthalocyanine. Zirconium phthalocyanine exhibiting good electrophotographic performances can be obtained through a similar process.

Abstract: A photoconductor for electrophotography includes a photosensitive film containing a bisazo charge generation agent described by structural formula (I) and from 100 nmol to 40 mmol, preferably from 500 nmol to 20 mmol, of a compound described by a structural formula (II) with respect to 1 mol of the bisazo charge generation agent. Such a photoconductor for electrophotography minimizes visual defects and image nonuniformity.

Abstract: Oxytitanium phthalocyanine having a novel crystal form having excellent electrophotographic properties, such as a high charge potential, a high sensitivity and stable performances free from causing changes in various properties in repeated use, can be produced in the absence of a halogen substance, by carrying out the crystal transformation of amorphous oxytitanium phthalocyanine in a solvent comprising water and naphthalene.

Abstract: A photoconductive imaging member containing a photogenerator layer comprised of a mixture of bis(methylbenzimidazo)perinone, optionally an (alkylimido)perylene, such as (n-pentylimido)perylene or mixtures of (n-pentylimido)perylene, bisbenzimidazo(2,1-a-1′,2′-b)anthra(2,1,9-def:6,5,10-d′e′f′)diisoquinoline-6,11-dione and bisbenzimidazo(2,1-a:2′,1′-a)anthra(2,1,9-def:6,5,10-d′e′f′)diisoquinoline-10,21-dione, and a charge transport layer.

Abstract: An electrophotographic photosensitive member is disclosed which has a support and a photosensitive layer and is exposed to semiconductor laser light having a wavelength of from 380 nm to 500 nm. The photosensitive layer contains a gallium phthalocyanine compound, or an oxytitanium phthalocyanine compound having a strong peak at 27.2° plus-minus 0.2° of the diffraction angle in CuK&agr; characteristic X-ray diffraction. Also, disclosed are a process cartridge and an electrophotographic apparatus making use of the photosensitive member.

Abstract: The present invention provides an electrophotosensitive material comprising a conductive substrate and a photosensitive layer provided on the conductive substrate, the photosensitive layer comprising a specific hole transferring material and/or electron transferring material and a binding resin of a polyester resin which is a substantially linear polymer obtained by using a specific dihydroxy compound represented by the general formula (1): wherein R1 is an alkylene group having 2 to 4 carbon atoms; and R2, R3, R4 and R5 are the same or different and indicate a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group or an aralkyl group or the like. This photosensitive material is improved in sensitivity, and is also superior in adhesion to conductive substrate as well as mechanical strength such as wear resistance, etc.

Abstract: An electrophotographic photosensitive member is disclosed which is comprised of a support and a photosensitive layer provided thereon and is exposed to semiconductor laser light having a wavelength of from 380 nm to 500 nm. The photosensitive layer contains an azo pigment represented by the general formula: Ar—(—N═N—Cp)n.

Abstract: A photoconductive imaging member comprised of a supporting substrate, a photogenerating layer, and a charge transport layer, and wherein said photogenerating layer is comprised of a mixture of a hydroxygallium phthalocyanine and a tetrafluoro hydroxygallium phthalocyanine.

Abstract: Naphthalenetetracarboxylic acid diimide derivatives represented by the general formula (1), wherein m and n are integers inclusive of 0 but not larger than 6, and are different from each other, R1 is a hydrogen atom, an alkyl group, an alkoxyl group or a halogen atom, either one of R2 or R3 is a substituted or unsubstituted aryl group, and the other one is an alkyl group, an alkoxyl group or an amino group, and wherein when R2 or R3 is an alkoxyl group or an amino group, the number n or m of methylene chains to which this group is bonded is not zero. The derivatives exhibit excellent solubility in an organic solvent, excellent compatibility with a resin binder and excellent photosensitivity, and are very useful as an electron-transporting agent for the photosensitive material for electrophotography.

Abstract: An electrophotographic recording material comprising a conductive support and a photosensitive layer containing a photoconductive crystalline substituted metal-free phthalocyanine compound and/or mixed crystals of said substituted metal-free phthalocyanine compounds with unsubstituted metal-free phthalocyanine, wherein said substituted metal-free phthalocyanine compound represented by general formula (I) defined herein contains a halogen, nitro or cyano substituent, and the major part by weight of said substituted metal-free phthalocyanine compound and the mixed crystals of said substituted metal-free phthalocyanine compound with unsubstituted metal-free phthalocyanine is (are) present in the X-morphological form.

Abstract: A mixture comprised of at least two perylenes and wherein the mixture includes symmetrical perylenes, unsymmetrical perylenes, and unsymmetrical perylenes with dissimilar R.sub.1 and R.sub.2 terminal substituents. The perylene mixtures can be selected for photoconductive imaging members.

Abstract: A photoconductive imaging member comprised of an unsymmetrical perylene of the formula ##STR1## wherein each R.sub.1 and R.sub.2 are dissimilar and wherein the R.sub.1 and R.sub.2 are hydrogen, alkyl, cycloalkyl, substituted alkyl, aryl, substituted aryl, aralkyl, and substituted aralkyl, and X represents a symmetrical bridging component, and y represents the number of X components.

Abstract: A process for preparing .chi.-form metal free phthalocyanine comprising: dry milling amorphous-like .alpha.-form metal free phthalocyanine to form .chi.-form metal free phthalocyanine partially; and wet milling or dispersing with stirring the resulting polymorph mixture in the presence of a cyclic organic solvent comprising an amide moiety. A simple process for preparing high-pure .chi.-form H2-Pc suitable as a charge generating meterial of an organic photoreceptor is provided, by improving the conventional technique for preparing .chi.-form H2-Pc.

Abstract: A photoconductor for electrophotography includes a photoconductive layer that contains titanyloxyphthalocyanine as a charge generation agent. The concentration of SO.sub.4.sup.2- with respect to the concentration of titanyloxyphthalocyanine is adjusted to be less than or equal to 500 ppm. The photoconductor may be of either a monolayer or a laminate construction. In the case of a laminate type photoconductor, the titanyloxyphthalocyanine is incorporated into the charge generation layer.

Abstract: A method of manufacturing an organic pigment including the steps of providing an organic pigment wet cake which includes at least an organic pigment and a solvent and drying the organic pigment wet cake while the wet cake is heated at a temperature higher than room temperature to prepare a powder of the organic pigment, wherein the organic pigment is present in the organic pigment wet cake in an amount of not greater than about 70% by weight.

Abstract: A di-substituted alkylene glycolate titanium phthalocyanine compound comprising a reaction mixture of a threo-alkanediol having one hydroxy group per each of the two adjacent carbon atoms, said carbon atoms each being a secondary carbon atom, and an oxytitanium phthalocyanine compound, and an organic photoconductor comprising the di-substituted alkylene glycolate titanium phthalocyanine compound are disclosed.

Abstract: The present invention provides novel .mu.-Oxo-aluminum/gallium phthalocyanine dimer having a structure of the formula (A): ##STR1## The .mu.-oxo-aluminum/gallium phthalocyanine dimer, and the mixed crystals comprising the .mu.-oxo-aluminum/gallium phthalocyanine dimer are suitable as a charge generating material for an organic photoconductive material, such as an electrophotographic photoreceptor.

Abstract: An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer on the conductive substrate. The photosensitive layer contains an arylamine compound of a formula (I): ##STR1## where A.sub.1, A.sub.2, A.sub.3 and A.sub.4 each independently represents a substituted or unsubstituted group selected from an alkyl group, an aralkyl group, an aryl group, a heterocyclic group and a condensed polycyclic group; Y represents a substituted or unsubstituted group selected from an alkylene group, an aralkylene group, an alkenylene group, an arylene group, and a bivalent heterocyclic group; and R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.

Abstract: A pigment includes a compound with a tetraazaporphyrin skeleton represented by formula (I): ##STR1## wherein M is a hydrogen atom, or an atom or compound capable of bonding to tetraazaporphyrin through a covalent bond or a coordinate bond; and R.sup.1 to R.sup.8 are each independently a hydrogen atom, a lower alkyl group which may have a substituent, or an aryl group which may have a substituent. In addition, the above-mentioned pigment is used as a charge generation material in an electrophotographic photoconductor comprising an electroconductive support and a photoconductive layer formed thereon.

Abstract: An electrophotographic photoconductor has an electroconductive support, and a photoconductive layer formed thereon which contains as a charge generation material a pigment including a compound with a tetraazaporphyrin skeleton represented by formula (I): ##STR1## wherein M is a hydrogen atom, or an atom or compound capable of bonding to tetraazaporphyrin through a covalent bond or a coordinate bond; and R.sup.1 to R.sup.4 are each independently a hydrogen atom, a lower alkyl group which may have a substituent, or an aryl group which may have a substituent.

Abstract: A family of photoreceptors for use in electrophotography are disclosed which contain a binary charge generation composition of oxytitanium phthalocyanine and copper phthalocyanine. The charge generation composition exhibits adjustable photosensitivity by adjusting a ratio between said oxytitanium phthalocyanine and said copper phthalocyanine. To optimize its performance, the charge generation composition is subject to an ammonia-modified complexation-mediated crystal transformation, and the resultant composition is characterized by Bragg diffraction angles (2.theta..+-.2.degree.) of 7.7, 9.4, 10.7, 13.3, 15.2, 15.7, 26.3, 27.4, and 28.4 degrees with respect to the CuK.alpha. characteristic X-ray wavelength at 1.54 .ANG. and absorption maxima centered around 615, 690, and 770 nm in the optical absorption spectrum.

Abstract: An electrophotographic photoreceptor which is excellent in sensitivity, durability and environmental capability comprises a photosensitive layer containing dihydroxysilicon phthalocyanine which is monoclinic and has lattice constants a=12.8.+-.1.ANG., b=14.5.+-.1.ANG., c=6.8.+-.1.ANG. and .beta.=94.4.+-.1.degree..

Abstract: An object of the invention is to provide a highly characteristic image using an electrophotographic photoreceptor of which a charge-generating layer can be produced with a better coating property and which is highly sensitive and electrostatically highly stable in repeated use. The charge-generating layer of a function-separated type photoreceptor contains a n-type non-metallic phthalocyanine and a copolymer of vinyl chloride-vinyl acetate type. Particularly, the ratio of the .tau.-type non-metallic phthalocyanine to the copolymer of vinyl chloride-vinyl acetate type is fixed at 1/3-3/1 by weight. The thickness of the charge-generating layer is fixed at 0.1-0.6 .mu.m. As the copolymer of vinyl chloride-vinyl acetate type, copolymers of vinyl chloride-vinyl acetate, vinyl chloride-vinyl acetate-maleic acid, or vinyl chloride-vinyl acetate-vinyl alcohol are selected. Particularly, it is favorable to select those containing at least 10% by weight of the vinyl alcohol component.

Abstract: Photoconductive imaging members comprised of a mixture of dimeric perylenes as a charge generator, wherein said mixture comprises at least perylenes encompassed by the following formulas, or mixtures thereof ##STR1## wherein R is hydrogen, alkyl, cycloalkyl, oxaalkyl, substituted alkyl, aryl, substituted aryl, aralkyl or substituted aralkyl; and X is a symmetrical bridging moiety, and X--Y represents an unsymmetrical bridging moiety.

Abstract: A photoconductive drum of an aluminum substrate and a blend of polyvinylbutyral and one or a blend of phenoxy resin, epoxy novolac resin, and epoxy capped polymers which are derivatives of bisphenol and epichlorohydrin. The blend enhances the electrical properties.

Abstract: An electrophotographic photoreceptor is disclosed. It comprises a photosensitive layer on an electrically conductive support and the photosensitive layer contains at least one compound of 0.001 to 10 weight percent selected from dioxolan and dioxolan derivatives, and titanylphthalocyanine or titanylphthalocyanine/vanadylphthalocyanine mixed crystal.

Abstract: The present invention provides .mu.-oxo-gallium phthalocyanine dimer having a novel polymorph. The .mu.-oxo-gallium phthalocyanine dimer may be applied as a charge generator for an organic photoconductive material, such as a photoreceptor of practical use and a high-gamma photoreceptor. The resulting organic photoconductive material has good stability and good electronic properties. The .mu.-oxo-gallium phthalocyanine dimer having a novel polymorph which shows diffraction peaks at a Bragg angle (2.theta..+-.0.2.degree.) of 6.8.degree., 12.9.degree., 19.0.degree., 19.6.degree., 20.3.degree., 25.5.degree., 25.9.degree. and 26.9.degree. in an X-ray diffraction spectrum by CuK .alpha.-ray.

Abstract: A crystalline titanyl phthalocyanine having diffraction peaks at least at 7.4.degree., 9.4.degree., 9.7.degree. and 27.3.degree. of Bragg angle (20.+-.0.2.degree.) in X-ray diffraction pattern with a doublet peak at 9.4.degree. or 9.7.degree., one of the diffraction peaks at 9.4.degree. and 9.7.degree. being the maximum.

Abstract: A single-layer binder comprising a synthetic resin binder and a phthalocyanine pigment dispersed therein is modified so as to reduce the content of the phthalocyanine pigment while maintaining or further improving the sensitivity of the binder. A coating material comprising a synthetic resin binder comprising as a constituent component a polyester resin containing halogen atoms, e.g., chlorine or bromine, and a phthalocyanine pigment dispersed in the binder is applied to a conductive base to produce an electrophotographic binder.

Abstract: An electrophotographic photoconductor having an electrically conductive substrate and a photosensitive layer formed on the conductive substrate is provided wherein the photosensitive layer comprises a layer that contains titanyl oxyphthalocyanine as a photoconductive material, and alkyl polyol that is diol or higher polyol and has hydroxyl groups for every three carbon atoms in a main chain of the alkyl polyol. The content of the alkyl polyol is controlled such that the amount of the hydroxyl groups of the alkyl polyol is in a range of 0.1 mol to 100 mol per 1 mol of titanyl oxyphthalocyanine. A method of manufacturing this electrophotographic photoconductor is also disclosed.

Abstract: An electrophotographic photosensitive member having a high sensitivity to long-wavelength light as emitted by a semiconductor laser and causing little change in potential change during repetitive use is formed by using as a charge-generating material a hydroxygallium phthalocyanine having a crystal form characterized by a strongest peak at a Bragg angle (2.theta..+-.0.2 deg.) of 28.1 deg. in a CuK.sub..alpha. characteristic X-ray diffraction pattern. The hydroxygallium phthalocyanine may preferably be produced through a process including treating a halogenated gallium phthalocyanine for conversion into a hydrous hydroxygallium phthalocyanine, freeze-drying the hydrous hydroxygallium phthalocyanine into a low-crystallinity hydroxygallium phthalocyanine, and milling the low-crystallinity hydroxygallium phthalocyanine.

Abstract: The present invention provides an electrophotographic photoreceptor which can be prepared so easily as to exhibit a photosensitivity well-adjusted for the respective type of machine in the dip coating method, which is an ordinary method for the preparation of an electrophotographic photoreceptor. A novel electrophotographic photoreceptor is provided comprising a charge-transporting layer and a charge-generating layer provided on an electrically-conductive support, wherein the charge-generating layer is a layer comprising a charge-generating material containing a phthalocyanine compound represented by the following general formula (1) dispersed in a resin: ##STR1## wherein Ar.sup.1 and Ar.sup.2 each independently represent an orthophenylene group which may have a substituent; and Pc represents an unsubstituted or substituted phthalocyanine residue.