Abstract: An electrophotographic photosensitive member, a process cartridge having the electrophotographic photosensitive member and an electrophotographic apparatus are provided. The electrophotographic photosensitive member has a conductive substrate and a photosensitive layer thereon, wherein the photosensitive layer contains a disazo pigment represented by the following formula (1): ##STR1## wherein R.sub.1 to R.sub.8 are the same or different and are each a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, n is a positive integer, A.sub.1 and A.sub.2 are the same or different and are each a coupler residual group having a phenolic hydroxyl group, and at least one of A.sub.1 and A.sub.2 is a coupler residual group represented by the following formula (2): ##STR2## wherein X.sub.1 is a residual group forming a polycyclic aromatic ring or a heterocyclic ring by condensing with a benzene ring, R.sub.9 and R.sub.

Abstract: According to the present invention, there is provided a novel tryptoanthorine derivative represented by the formula: ##STR1## wherein R.sup.1a, R.sup.1b, R.sup.1c, R.sup.1d, R.sup.2a, R.sup.2b, R.sup.2c, and R.sup.2d are the same or different and indicate a hydrogen atom, an alkyl group or a halogenated alkyl group; provided that R.sup.1a, R.sup.1b, R.sub.1c and R.sup.1d do not indicate a hydrogen atom, simultaneously. Tryptoanthorine and a derivative thereof are suitably used for an electrophotosensitive material because of their excellent electron transferring capability.

Abstract: Cocrystallized titanyl phthalocyanine-titanyl fluorophthalocyanine compositions, preparation methods, and electrophotographic elements utilizing the compositions. The method has the steps of: admixing crude titanyl phthalocyanine and crude titanyl fluorophthalocyanine to provide a pigment mixture; increasing the amorphousness of the pigment mixture as determined by X-ray crystallography using X-radiation characteristic of Cu K.alpha. at a wavelength of 1.541 .ANG. of the Bragg angle 2.theta. to provide an amorphous pigment mixture; contacting the amorphous pigment mixture with organic solvent having a gamma.sub.c hydrogen bonding parameter of less than 8.0; and prior to the contacting, substantially excluding the amorphous pigment mixture from contact with organic solvent having a gamma.sub.c hydrogen bonding parameter greater than 9.0.

Abstract: An electrophotographic photoconductor includes an electroconductive substrate, and a photoconductive layer formed thereon containing at least one tertiary amine compound of formula (I) as an effective component: ##STR1## wherein Ar.sup.1 and Ar.sup.3 each is an aryl group which may have a substituent; Ar.sup.2 is a bivalent group of a carbocyclic aromatic compound or a bivalent group of a heterocyclic compound; R.sup.1 is a hydrogen atom, an alkyl group which may have a substituent or an alkoxyl group which may have a substituent; and R.sup.2 is a hydrogen atom, an alkyl group which may have a substituent or an aryl group which may have a substituent. A novel triphenylamine compound for use in the electrophotographic photoconductor is provided.

Abstract: The electrophotgraphic photoreceptor is composed of an electrically conductive substrate having formed thereon a photosensitive layer containing a phthalocyanine mixed crystal comprising titanyl phthalocyanine and hydrogen phthalocyanine, wherein the phthalocyanine mixed crystal has peaks at 6.8.degree., 7.4.degree., 15.0.degree., 24.7.degree., 26.2.degree., and 27.2.degree. of the Bragg angle (2 .theta..+-.0.2.degree.) in the X-ray diffraction spectrum and having a ratio of the peak intensity at 27.2.degree. to the peak intensity at 6.8.degree. of 1 or more. The electrophotographic photoreceptor can output the output signals as digital signals even when the input light is a digital light or an analog light and thus the electrophotographic photoreceptor can be used for an electrophotograph of a digital recording system and even when the photorecetor is used as a conventional photoreceptor for PPC (analog light input), high-quality images having sharp edges can be obtained.

Abstract: A new crystalline form of oxytitanium phthalocyanine is characterized by main peaks specified by Bragg angles (2.theta..+-.0.2 degrees) of 7.4 degrees, 10.2 degrees, 12.5 degrees, 15.0 degrees. 16.3 degrees, 18.3 degrees, 22.4 degrees, 24.2 degrees, 25.2 degrees and 28.5 degrees in X-ray diffraction pattern based on CuK.alpha. characteristic X-rays. The oxytitanium phthalocyanine is formed by treating amorphous oxytitanium phthalocyanine with a solvent selected from the group consisting of monohydric alcohols having at least two carbon atoms, cellosolves, diethylene glycol monoethers and diacetone alcohol. The oxytitanium phthalocyanine is useful as a charge generating material for providing an electrophotographic photosensitive member, which shows a stably high sensitivity to long wavelength light.

Abstract: An electrophotographic photoconductor, includes metal-free phthalocyanine as a charge-generating substance, wherein the X-ray diffraction spectrum of said metal-free phthalocyanine as measured using CuK.alpha. as a radiation source includes intense diffraction peaks at Bragg angles (2.theta..+-.0.2.degree.) of 7.5.degree., 9.0.degree., 16.6.degree., 17.2.degree., 21.5.degree., 22.2.degree., 23.8.degree., and 28.5.degree., and wherein the infrared absorption spectrum of said metal-free phthalocyanine includes four absorption bands with the maximum absorption intensity at a wavenumber of 716 cm.sup.-1 between a wavenumber of 700 cm.sup.-1 and a wavenumber of 760 cm.sup.-1 and a characteristic absorption band at a wavenumber of 3,291.+-.2 cm.sup.-1.

Abstract: Disclosed is an electrophotographic photoreceptor comprising a conductive support and provided thereon an intermediate layer, a carrier generation layer containing a carrier generation material and a carrier transportation layer containing a carrier transportation material, wherein said carrier generation layer contains a first perylene compound represented by Formula A and a second perylene compound represented by Formula B as said carrier generation material: ##STR1## wherein Z represents a substituted or unsubstituted divalent aromatic hydrocarbon group or a substituted or unsubstituted divalent heterocyclic group; and R represents an alkyl group, an aralkyl group, a hydroxyalkyl group, an alkoxyalkyl group, an aromatic hydrocarbon group or a heterocyclic group; ##STR2##

Abstract: A photoconductive imaging member comprised of a supporting substrate, a hydroxygallium phthalocyanine photogenerator layer, a charge transport layer, a photogenerator layer comprised of a mixture of 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 as a top layer a charge transport layer.

Abstract: An electrophotographic photoconductor includes an electroconductive support and a single-layered photoconductive layer formed thereon, containing a charge transporting material, a binder resin, and a simultaneously pulverized mixture including at least one disazo pigment of formula (1) and at least one trisazo pigment of formula (2), which is obtained by simultaneously pulverizing those azo pigments: ##STR1## wherein R.sup.1 and R.sup.2 each is hydrogen, a halogen atom, trifluoromethyl group, nitro group or cyano group; R.sup.3 is hydrogen, chlorine, fluorine, iodine, bromine, nitro group or cyano group; and Ar.sup.1, Ar.sup.2 and Ar.sup.3 each is a coupler radical, which may be the same or different.

Abstract: An electrophotographic photosensitive member is constituted by disposing a photosensitive layer on a support. The photosensitive layer contains oxytitanium phthalocyanine and a specific disazo pigment of the formula (I) or (II) each characterized by having particular coupler residues. The photosensitive layer may preferably include a charge generation layer and a charge transport layer. The charge generation layer may preferably include a first charge generation layer containing the above disazo pigment of the formula (I) or (II) and a second charge generation layer containing the above oxytitanium phthalocyanine. The electrophotographic photosensitive member including the photosensitive layer described above is usable for providing an apparatus unit and an electrophotographic apparatus showing excellent electrophotographic characteristics such as high photosensitivity, good potential stability in repetitive use and good image-forming properties substantially providing no black spots.

Abstract: An organic photoconductive material is represented by the following general formula [1]:A.sub.1 --N.dbd.N--B--N.dbd.N--A.sub.2 [1],wherein B is a divalent organic group bonded to nitrogen atoms forming azo groups, A.sub.1 and A.sub.2 are groups different from each other, A.sub.1 is represented by the following general formula [A1]: ##STR1## wherein X is an atomic group which is necessary for forming an aromatic hydrocarbon ring or an aromatic hetero-ring by condensation with the benzene ring, Y is a hydrogen atom, an alkyl group, an alkoxy group or a halogen atom, m is an integer of 1 to 4, R is an aromatic hydrocarbon ring group or an aromatic hetero-ring group and n is 1 or 2, and A.sub.2 is a group represented by one of the following general formulae [A2] and [A3]: ##STR2## wherein a.sub.1 is a group selected from R, --N.dbd.CH--R and ##STR3## R, X, Y, m and n are the same as those in the general formula [A1] and p is 0 or 1.

Abstract: An ammonia-modified titanyl phthalocyanine for use in preparing charge generating layer of a photoreceptor is disclosed. The ammonia-modified titanyl phthalocyanine is obtained by a process comprising the following steps: (a) reacting titanium tetrachloride with halogen-containing naphthalene to obtain an unmodified titanyl phthalocyanine; (b) dispersing the unmodified titanyl phthalocyanine in an organic solvent; and (c) subjecting the unmodified titanyl phthalocyanine to an ammonia-induced complexation-mediated crystal transformation so as to obtain the ammonia-modified titanyl phthalocyanine. The ammonia-induced complexation-mediated crystal transformation step can be achieved by either bubbling ammonia gas through the titanyl phthalocyanine-containing organic solution or by adding an ammonia-saturated aqueous solution to the titanyl phthalocyanine-containing organic solution. The ammonia-modified titanyl phthalocyanine is characterized by having Bragg diffraction angles of 7.5, 9.3, 13.6, 14.3, 17.9, 24.

Abstract: A process for the preparation of hydroxygallium phthalocyanines Type A, Type B, Type C, or Type D, which comprises contacting Type V hydroxygallium phthalocyanine with an alcohol.

Abstract: A phthalocyanine pigment dispersion using a dispersing polymer having pendant quaternary ammonium salt groups to form a highly dispersed and stable millbase is described. The pigment dispersion is compatible with poly(vinylbutyral) resins and stable in ketone solvents. The pigment dispersion is particularly useful as a charge-generating or charge-transport material in an organic photoconductor construction.

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 tetrafluoro hydroxygallium phthalocyanine.

Abstract: An electrophotographic imaging member is characterized by a halogenindium phthalocyanine produced by dry milling and treating with an organic amine solvent.

Abstract: An electrophotographic photoreceptor comprising a conductive substrate having provided thereon a photosensitive layer, wherein said photosensitive layer contains, as charge transporting material (i) at least one triarylamine compound represented by formula (I) ##STR1## wherein the definition of Ar.sub.1, Ar.sub.2 are described in the present specification; and (ii) at least one benzidine compound represented by formula (II) ##STR2## wherein the definition of R.sub.1, R.sub.1 ', R.sub.2, R.sub.2 ', R.sub.3, R.sub.3 ', m and n is described in the specification. The photoreceptor maintains its electrical characteristics stably on repeated use.

Abstract: An organic positive-charging photoconductor (+) OPC is disclosed. The (+) OPC has a conductive substrate; a hydroxy-containing binder component forming a layer greater than or equal to about 1 micron thick on said substrate; an X-type, metal-free phthalocyanine pigment component uniformly distributed throughout said binder component; and a reactive additive component selected from the list of cross-linkable resins, carboxlyic acid anhydrides, aldehydes, poly-ols, alkoxy silane coupling agents, reactive allyl polymers and dismaleimides, the reactive additive component also being uniformly distributed throughout, and being in cross-linked relation with, the hydroxy-containing binder component with an electron withdrawing functional group and an electron donating functional group in the same molecule. The (+) OPC, which may also contain a co-additive component, exhibits increased stability in a laser printing process.

Abstract: An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer thereon. The photosensitive layer contains a disazo pigment having a 1,2-benzofluorenone as a central structure. A process cartridge and an electrophotographic apparatus containing the electrophotographic photosensitive member is also provided.

Abstract: An electrophotographic element and a preparation method. The element has a charge generation layer including binder and, dispersed in the binder, a physical mixture of: a high speed titanyl fluorophthalocyanine and a low speed titanyl fluorophthalocyanine. The high speed titanyl fluorophthalocyanine has a first intensity peak with respect to X-rays characteristic of Cu K.alpha. at a wavelength of 1.541 .ANG. of the Bragg angle 2.theta. at 27.degree..+-.0.2.degree. and a second intensity peak at 7.3.degree..+-.0.2.degree.. The second peak has an intensity relative to the first peak of less than 60 percent. The low speed titanyl fluorophthalocyanine has a first intensity peak with respect to X-rays characteristic of Cu K.alpha. at a wavelength of 1.541 .ANG. of the Bragg angle 2.theta. at 6.7.degree..+-.0.2.degree. and a second intensity peak at 23.7.degree..+-.0.2. The second peak has an intensity relative to the first peak of less than 50 percent.

Abstract: A novel electrophotographic photoreceptor is provided, comprising on an electrically conductive support a light-sensitive layer containing at least one acetylene disazo compound represented by the general formula (I):Cp--N.dbd.N--Ar.sup.1 --C.tbd.C--Ar.sup.2 N.dbd.N--Cp (I)wherein Ar.sup.1 and Ar.sup.2 each represents an unsubstituted or substituted arylene group, divalent condensed polycyclic aromatic group or divalent aromatic heterocyclic group, with the proviso that Ar.sup.1 and Ar.sup.2 are not phenylene groups at the same time; and Cp represents a coupler residue.

Abstract: A methoxy gallium phthalocyanine compound represented by formula (I): ##STR1## wherein X represents a chlorine atom, a bromine atom, or an iodine atom; and n represents an integer of from 0 to 4; and an electrophotographic photoreceptor using the methoxy gallium phthalocyanine compound.

Abstract: A process for preparing a titanyl phthalocyanine crystal showing at least one diffraction peak at a Bragg angle (2.theta..+-.0.2) of 27.3.degree. is disclosed, which comprises dissolving or suspending titanyl phthalocyanine in concentrated sulfuric acid to form a solution or a slurry and diluting the solution or slurry with an alcohol solvent, an aromatic solvent, a mixed solvent of an alcohol solvent and water, a mixed solvent of an aromatic solvent and water, or a mixed solvent of an alcohol solvent and an aromatic solvent with or without water thereby to precipitate a crystal, and, if desired, treating the precipitated crystal with an alcohol solvent, an aromatic solvent, a mixed solvent of an alcohol solvent and an aromatic solvent or a mixed solvent of an alcohol solvent and/or an aromatic solvent and water. The resulting titanyl phthalocyanine crystal exhibits high photosensitivity and excellent durability as a photoconductive material of an electrophotographic photoreceptor.

Abstract: There are provided a hydrazone compound represented by formula (I), an electrophotographic photoreceptor which has a photosensitive layer containing the compound on an electrically conductive support, and an organic electroluminescent element containing the compound as a charge transporting material: ##STR1## wherein Ar.sub.1 represents a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted biphenylene group, or a substituted or unsubstituted anthrylene group, Ar.sub.2 represents a substituted or unsubstituted aryl group, R.sub.1 and R.sub.2 each independently represents a hydrogen atom, a halogen atom, an unsubstituted alkyl group, or an unsubstituted alkoxy group, R.sub.3 represents an unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted aryl group, Z represents an ethylene group or a vinylene group, and n is 0 or 1.

Abstract: Gallium phthalocyanine halide crystals wherein a part of the crystals are changed into hydroxygallium phthalocyanine is disclosed. A method for preparing gallium phthalocyanine halide crystals wherein gallium phthalocyanine halide crystals are brought into contact with water and a part of the crystals are changed into hydroxygallium phthalocyanine is also disclosed. An electrophotographic photoreceptor formed by laminating at least a charge generating layer and a charge transporting layer successively on a conductive support wherein the charge generating layer contains gallium phthalocyanine halide crystals An which a part of the crystals are changed into hydroxygallium phthalocyanine is also disclosed.

Abstract: Certain perylene-3,4:9,10-tetracarboxylic monoanhydride monoimides are condensed with primary diamines or with imidazoles. The products obtained are amidine imides of the formula I ##STR1## where, for example, R.sub.1 is 1-hexylheptyl, R.sub.2 to R.sub.5 are each H and A is 1,2-phenylene. Compounds of the formula I are very light-fast dyes which show strong fluorescence in solution and whose fluorescence occurs at a longer wavelength than that of the bisimides (perylene dyes). The perylene amidine imides of the invention are suitable for example for use as colorants for the mass coloration of macromolecular organic material, as fluorescent dyes or as photoconductors.

Abstract: An electrophotographic photoreceptor is herein disclosed which comprises a conductive support and a photosensitive layer formed on the conductive support, and the photosensitive layer contains an enamine derivative as a carrier transport material represented by the formula ##STR1## wherein Ar is an aryl group which may have a substituent, a heterocyclic group which may have a substituent, an aralkyl group which may have a substituent, or a heterocyclic substituted alkyl group; and n is 2, 3 or 4.The electrophotographic photoreceptor is excellent in sensitivity and durability.

Abstract: An electrophotographic photoreceptor including a light-sensitive layer containing a bisazo or trisazo compound represented by formula (I-1), (II-1), (III,1), (IV-1), (V-1) or (VI-1): ##STR1##

Abstract: The present invention provides an electrographic printing photosensitive resin composition, which exhibits a good photosensitivity in a negative corona charging system and is useful for a laser platemaking system using semi-conductor laser light within a near infrared range as a light source.Disclosed is a negative charging type printing photosensitive resin composition comprising a phthalocyanine compound (a), a mercaptoarylimidazole (thiazole) compound (b) and, if necessary, a compound selected from the group consisting of a condensed polycyclic quinone compound, a bisazo compound, a cyanine compound, a quinacridone compound and a mixture thereof (d), said compounds being dispersed in a binder resin (c). A printing photosensitive resin plate using the photosensitive resin composition is also disclosed.

Abstract: Disclosed are a coating solution for forming a charge generation layer, which comprises:(A) a phthalocyanine composition,(B) a binder resin represented by the formula: ##STR1## wherein R represents an alkylene group, R.sup.1 represents an alkyl group; and m, n and k each represent a ratio of recurring unit numbers and are numerals satisfying the relations of k+m+n=1, n>m>0 and 0.3.gtoreq.k.gtoreq.0,(C) at least one of a melamine resin and a benzoguanamine resin in a 1- to 5-fold amount in terms of the weight ratio of the amount of the binder resin, and(D) a solvent having both a hydroxyl group and an ether group in one molecule,and an electrophotographic photoreceptor using the same.

Abstract: Disclosed are a phthalocyanine composition which comprises having main diffraction peaks at 7.5.degree., 22.5.degree., 24.3.degree., 25.3.degree. and 28.6.degree. of Bragg angles (2.theta..+-.0.2.degree.) in an X-ray diffraction spectrum with Cu K.alpha., a process for preparing the same, an electrophotographic photoreceptor using the same and a coating solution for a charge generation layer containing the same.

Abstract: An alternating copolymer comprising a repeating unit of the formula:-Z-(X-Y).sub.n - (I)wherein n is at least 2, X is O, S, Se or Te, and Y and Z are independently an aromatic or substituted aromatic group, and at least one other repeating unit, which is useful as a photosensitive material used in a spatial light modulator.

Abstract: An electrophotographic photosensitive member of the present invention has a photosensitive lazer containing a compound represented by the formula (1): ##STR1## The electrophotographic photosensitive member has a high sensitivity and can maintain stable and excellent electrophotographic characteristics even when repeatedly used.

Abstract: A process which comprises contacting the cis and trans isomers of benzimidazole perylene with cyclohexane.

Abstract: A halogen-containing hydroxygallium phthalocyanine crystal showing intense diffraction peaks at Bragg angles (2.theta..degree..+-.0.2.degree.) of (1) 7.7.degree., 16.5.degree., 25.1.degree. and 26.6.degree.; (2) 7.9.degree., 16.5.degree., 24.4.degree., and 27.6.degree.; (3) 7.0.degree., 7.5.degree., 10.5.degree., 11.7.degree., 12.7.degree., 17.3.degree., 18.1.degree., 24.5.degree., 26.2.degree., and 27.1.degree.; 4) 7.5.degree., 9.9.degree., 12.5.degree., 16.3.degree., 18.6.degree., 25.1.degree., and 28.3.degree.; or (5) 6.8.degree., 12.8.degree., 15.8.degree., and 26.0.degree. and an electrophotographic photoreceptor containing the halogen-containing hydroxygallium phthalocyanine crystal as a charge generating material are disclosed.

Abstract: A pyrazine compound of formula (I) and a pyrazine compound of formula (II): ##STR1## wherein R is an unsubstituted or substituted phenyl group, an unsubstituted or substituted naphthyl group; and an electrophotographic photoconductor which includes an electroconductive support and a photoconductive layer formed thereon containing a charge generating material and a charge transporting material which is any of the above-mentioned pyrazine compounds of formula (I) and formula (II).

Abstract: A process for preparing hydroxygallium phthalocyanine crystals showing intense diffraction peaks at Bragg angles (2.theta..+-.0.2) of 7.5.degree., 25.1.degree., and 28.3.degree. with respect to CuK.sub..alpha. characteristic X-rays which comprises mechanically grinding hydroxygallium phthalocyanine and then treating the grains with a solvent is disclosed. The hydroxygallium phthalocyanine crystals obtained by the process of the present invention has a novel crystal form and exhibits high sensitivity and excellent durability on repeated use as well as crystal form stability. The electrophotographic photoreceptor prepared by using the resulting hydroxygallium phthalocyanine exhibits excellent electrophotographic characteristics.

Abstract: Photoconductive imaging members comprised of an alkoxy-bridged metallophthalocyanine dimer as a charge generator material, wherein said dimer is of the formula C.sub.32 H.sub.16 N.sub.8 MOROMN.sub.8 H.sub.16 C.sub.

Abstract: Disclosed are a phthalocyanine composition which comprises having main diffraction peaks at 7.5.degree., 24.2.degree. and 27.3.degree. of Bragg angles (2.theta..+-.0.2.degree.) in an X-ray diffraction spectrum with Cu K.alpha., a process for preparing the same, an electrophotographic photoreceptor using the same and a coating solution for forming a charge generation layer containing the same.

Abstract: An electrophotographic photoreceptor high in sensitivity and contrast potential after light irradiation is disclosed. The photoreceptor comprises an electroconductive substrate having thereon a photoconductive layer comprising a charge generating layer comprising a charge generating material, and a charge transporting layer comprising a charge transporting material, wherein the ionization potential IPg of the charge generating material is lower than the ionization potential IPt of the charge transporting material, the difference therebetween is 0.35 eV or less, and the difference between the ionization potential IPg1 of the charge generating layer and the ionization potential IPt1 of the charge transporting layer is within the range of -0.1 to +0.1 eV.

Abstract: An electrophotographic photoreceptor comprising a conductive substrate having thereon a photosensitive layer comprising a binder resin having dispersed therein a phthalocyanine composition is disclosed, in which said binder resin is a curing fluorine resin, and said phthalocyanine composition comprises (A) an unsubstituted phthalocyanine compound and (B) a phthalocyanine derivative having a halogen atom(s) and/or electron attractive group(s) at the benzene nuclei, such that the ratio of the number of the halogen atom(s) and/or electron attractive group(s) to the total number of the phthalocyanine units in (A) and (B) is from 0.001 to 0.5. The photoreceptor has a low threshold value of photosensitive characteristics and exhibits high sensitivity in a digital behavior. Besides applicable to a digital recording system, the photoreceptor, when applied to a conventional PPC system, provides a sharp-edged high quality image.

Abstract: An imaging member comprised of an optional supporting substrate, a photogenerator layer, and a charge transport layer, and wherein the photogenerator layer is comprised of acetoxymetal phthalocyanine pigments as essentially represented by the formula ##STR1## where R is acetyl, haloacetyl, or mixtures thereof; R' is alkyl, alkoxy, cyano, halogen, or mixtures thereof; M is a metal selected from the group consisting of aluminum, gallium, silicon, germanium and indium; x is 1 or 2; and y is 0, 1 or 2.

Abstract: The present invention is directed to a photoreceptor having an electroconductive support, a barrier layer, a charge generation layer and a charge transport layer, all formed on the support in this order, wherein the barrier layer consists of an alcohol-soluble copolymerized polyamide resin, the charge generation layer contains a compound represented by formula I or II, and the charge transport layer contains a polycarbonate resin having a molecular weight of not less than 100,000, ##STR1## wherein Z represents a groups of atoms necessary to form a substituted or unsubstituted divalent aromatic ring.

Abstract: Low-molecular-weight and polymeric liquid-crystalline 2-substituted benzotriazoles of the formula ##STR1## are used as photoconductors or electrophotographic recording materials or as fluorescent dyes for fluorescent displays.

Abstract: Disclosed are naphthalocyanine compounds having siloxy groups bonded to a central metal silicon. The compounds can be used as a charge generating substance of an electrophotographic plate having high sensitivity to the longer wavelength light of about 800 nm without conducting a special treatment. The naphthalocyanine compounds are represented by the formula: ##STR1## wherein L is a group of the formula R.sub.1 R.sub.2 R.sub.3 SiO--, and R.sub.1, R.sub.2 and R.sub.3 are each a same alkyl group having 1-3 carbon atoms.

Abstract: A photosensitive material for electrophotography, comprises a support and, provided thereon, an organic photoconductive layer of single-layer structure comprising a binder polymer, an electron acceptor substance particulately dispersed in the binder polymer, and a metal-free phthalocyanine molecularly dispersed in the binder polymer.

Abstract: A process for the preparation of aryl amine polycondensation polymers useful in electrophotographic imaging members, which process comprises the interfacial polymerization of an aryl amine diol dissolved in an alkaline aqueous phase with a bifunctional acid halide dissolved in an organic solvent, resulting in polymers with high molecular weight and narrow molecular weight distribution (M.sub.w /M.sub.n) of from between about 50,000 to about 350,000, and a M.sub.w /M.sub.n of from about 1 to about 4.

Abstract: A composition of matter, useful in the production of organic photoconductor devices, comprising a dispersion of X-form metal-free phthalocyanine in an organic liquid containing an effective amount of a dispersant.

Abstract: A process for increasing the imaging cyclic stability of titanyl phthalocyanines by adding to said titanyl phthalocyanines a perylene.