Abstract: An electrophotographic photoconductor an electroconductive substrate, an intermediate layer comprising a charge generating azo pigment and a thermosetting resin, a charge generating layer and a charge transporting layer, which layers are successively overlaid on the electroconductive substrate, the charge generating azo pigment being any of the azo pigments (1) through (4): ##STR1##

Abstract: A disazo compound, having the general formula, ##STR1## wherein Y represents a substituted or non-substituted cyclic hydrocarbon or substituted or non-substituted heterocycle; R represents hydrogen, substituted or non-substituted alkyl group, or substituted or non-substituted phenyl group; andZ represents a substituted or non-substituted cyclic hydrocarbon or heterocycle fused with phenyl nucleus.

Abstract: An electrophotographic printing original plate is disclosed, which comprises an electroconductive support material and an electrophotographic photosensitive layer formed thereon, which electrophotographic photosensitive layer comprises (i) a charge generation layer consisting essentially of a particular azo pigment serving as a charge generating material and (ii) a charge transport layer consisting essentially of a charge transporting material and an alkali-soluble resin; and an electrophotographic printing plate making process using the above printing original plate is also disclosed, which comprises the steps of electrically charging uniformly the above printing original plate, exposing the charged printing original plate to optical images to form latent electrostatic images thereon, developing the latent electrostatic images with toner, fixing the toner images to the printing original plate, and removing the electrophotographic photosensitive layer portions corresponding to the non-image areas of the print

Abstract: This invention relates to a disazo compound, a method for producing said disazo compound and an electrophotographic element containing said disazo compound, said disazo compound has the general formula (I), ##STR1## wherein Y represents a substituted or non-substituted cyclic hydrocarbon or substituted or non-substituted heterocycle; R represents hydrogen, substituted or non-substituted alkyl group, or substituted or non-substituted phenyl group; and Z represents a substituted or non-substituted cyclic hydrocarbon or heterocycle fused with phenyl nucleus.

Abstract: The present invention provides an multilayer type electrophotographic element comprising laminating a charge generating layer containing a trisazo pigment represented by the general formula (1) on an electrically conductive substrate: ##STR1## (wherein, R denotes ##STR2## and laminating a charge transfer layer containing an .alpha.-substituted stilbene compound represented by the general formula (2): ##STR3## (wherein, R.sup.1 denotes a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, R.sup.2, R.sup.3, and R.sup.4 each denotes a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, and Ar.sup.2 denotes a substituted or unsubstituted arylene group. Ar.sup.1 and R.sup.1 may be combined to form a ring. n is an integer of 0 or 1) and a resinous binder, on the charge generating layer.

Abstract: An electrophotographic photoconductor is disclosed, which comprises an electroconductive support material and a photosensitive layer comprising at least one 1,3-dithiol derivative of the formula ##STR1## wherein R.sup.1 and R.sup.2 independently represent hydrogen, a substituted or unsubstituted phenyl group, or R.sup.1 and R.sup.2 in combination can form a ring; R.sup.3 represents hydrogen or an alkyl group; and R.sup.4 and R.sup.5 independently represent an alkyl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted aryl group.

Abstract: Trisazo compounds having the following general formula I: ##STR1## are useful as charge carrier generating materials for electrophotographic elements. Multilayer electrophotographic elements having a charge carrier generating layer containing these compounds as charge carrier generators and having a separate charge transport layer containing a charge transport material are particularly excellent in sensitivity in the 780-800 nm wavelength region.

Abstract: An electrophotographic photoconductor is prepared by forming a photoconductive layer containing a hydrazone compound therein on an electroconductive support member. The hydrazone compounds represented by the following general formula, are useful as photoconductive materials and as charge transport materials for use in electrophotography: ##STR1## wherein R.sub.1 represents a methyl group, an ethyl group, a 2-hydroxyethyl group, or a 2-chloroethyl group, and R.sub.2 represents a methyl group, an ethyl group, a benzyl group or a phenyl group.

Abstract: An electrophotographic element comprising an electrically conductive substrate, a charge carrier generating layer and a charge transfer layer superimposed on said substrate, wherein said charge carrier generating layer contains a trisazo compound having the general formula (I): ##STR1## (wherein, Ar represents ##STR2## and said charge transfer layer contains a charge transfer substance having the general formula (II) or (III): ##STR3## (wherein, R.sup.1 represents a hydrogen or halogen atom, R.sup.2 represents hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, a dialkylamino group, or a substituted or non-substituted diaralkylamino group, and R.sup.3 represents hydrogen, an alkyl group or a halogen atom.) ##STR4## (wherein, R.sup.

Abstract: An electrophotographic element comprising an electrically conductive substrate, a charge carrier generating layer and a charge transfer layer superimposed on said substrate, wherein said charge carrier generating layer contains a trisazo compound having the general formula (I): ##STR1## (wherein, Ar.sup.1 represents a substituted or unsubstituted phenyl radicalandsaid charge transfer layer contains a hydrazone compound having the general formula (II), (III), (IV), or (V): ##STR2## (wherein, R.sup.1 represents a methyl group, an ethyl group, a 2-hydroxyethyl group or a 2-chloroethyl group, R.sup.2 represents a methyl group, an ethyl group, a benzyl group or a phenyl group, and R.sup.3 represents hydrogen, chlorine, an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, a dialkylamino group or a nitro group.), ##STR3## (wherein, Ar.sup.

Abstract: The present invention provides disazo compounds expressed by the general formula ##STR1## [wherein A represents ##STR2## (wherein R represents alkyl radical, alkoxy radical, nitro radical, dialkylamino radical or halogen, n is 0 or an integer ranging from 1 to 3, and R may be identical or different when n is an integer of 2 or 3)]; a process for the preparation of said compounds; and photosensitive materials having a high sensitivity as well as a high flexibility which comprises a conductive support and a photosensitive layer formed thereon, said photosensitive layer containing a disazo pigment, as an effective ingredient, which is expressed by the general formula ##STR3## [wherein R' represents a member selected from the group consisting of hydrogen, ethyl radical, chloroethyl radical and hydroxyethyl radical, A' represents a member selected from the group consisting of ##STR4## (wherein X represents a member selected from the group consisting of aromatic rings such as benzene ring, naphthalene ring, etc.

Abstract: An electrophotographic photoconductor is prepared by forming a photoconductive layer containing a hydrazone compound therein on an electroconductive support member. The hydrazone compounds represented by the following general formula, are useful as photoconductive materials and as charge transport materials for use in electrophotography: ##STR1## wherein R.sub.1 represents a methyl group, an ethyl group, a 2-hydroxyethyl group, or a 2-chloroethyl group, and R.sub.2 represents a methyl group, an ethyl group, a benzyl group or a phenyl group.

Abstract: Bis-azo compounds represented by the general formula ##STR1## where A represents ##STR2## wherein R represents alkyl, alkoxy, nitro, dialkylamino or halogen, and n represents an integer 0, 1, 2 or 3 and when n is 2 or 3, R represents identical or different substituents selected from the group of alkyl, alkoxy, nitro, dialkylamino and halogen.

Abstract: The present invention provides electrophotographic sensitive materials having a high sensitivity as well as a high flexibility which comprise a conductive support and a photosensitive layer formed thereon, said photosensitive layer containing one disazo pigment, as an effective ingredient, which is selected from the group consisting of disazo pigments expressed by the following general formulas I, II, III, and IV, ##STR1## [(wherein A is selected from the group consisting of ##STR2## is selected from the group consisting of aromatic rings such as benzene ring, naphthalene ring, etc., hetero rings such as indole ring, carbazole ring, benzofuran ring, etc. and their substituents, Ar.sub.1 is selected from the group consisting of aromatic rings such as benzene ring, naphthalene ring, etc., hetero rings such as dibenzofuran, etc. and their substituents, Ar.sub.2 and Ar.sub.3 are selected from the group consisting of aromatic rings such as benzene ring, naphthalene ring, etc. and their substituents, R.sub.1 and R.

Abstract: An electrophotographic element utilizing as a charge generation material a disazo pigment having the following general formula: ##STR1## where R.sup.1 is hydrogen, chlorine, bromine, methyl, ethyl, methoxy, ethoxy, nitro, dimethylamino, diethylamino or phenyl; m and n are each an integer such as 1 or 2; and R.sup.2 is hydrogen or chlorine.

Abstract: The present invention provides electrophotographic sensitive materials having a high sensitivity as well as a high flexibility which comprise a conductive support and a photosensitive layer formed thereon, said photosensitive layer containing one disazo pigment, as an effective ingredient, which is selected from the group consisting of disazo pigments expressed by the following general formulas I, II, III, and IV, ##STR1##

Abstract: The present invention provides disazo compounds expressed by the general formula: ##STR1## [wherein A represents a member selected from the group consisting of ##STR2## (wherein X represents a member selected from the group consisting of aromatic rings such as benzene ring, naphthalene ring, etc., hetero rings such as indole ring, carbazole ring, benzofuran ring, etc. and their substituents, Ar.sub.1 represents a member selected from the group consisting of aromatic rings such as benzene ring, naphthalene ring, etc., hetero rings such as dibenzofuran ring, etc. and their substituents, Ar.sub.2 and Ar.sub.3 represent a member selected from the group consisting of aromatic rings such as benzene ring, naphthalene ring, etc. and their substituents, R.sub.1 and R.sub.3 represent a member selected from the group consisting of hydrogen, lower alkyl radical or phenyl radical and their substituents and R.sub.

Abstract: The present invention provides disazo compounds expressed by the general formula ##STR1## [wherein A represents ##STR2## (wherein R represents alkyl radical, alkoxy radical, nitro radical, dialkylamino radical or halogen, n is 0 or an integer ranging from 1 to 3, and R may be identical or different when n is an integer of 2 or 3)]; a process for the preparation of said compounds; and photosensitive materials having a high sensitivity as well as a high flexibility which comprises a conductive support and a photosensitive layer formed thereon, said photosensitive layer containing a disazo pigment, as an effective ingredient, which is expressed by the general formula ##STR3## [wherein R' represents a member selected from the group consisting of hydrogen, ethyl radical, chloroethyl radical and hydroxyethyl radical, A' represents a member selected from the group consisting of ##STR4## (wherein X represents a member selected from the group consisting of aromatic rings such as benzene ring, naphthalene ring, etc.

Abstract: The present invention provides trisazo compounds expressed by the general formula I ##STR1## [wherein A represents ##STR2## (wherein R represents hydrogen, alkyl radical, alkoxy radical, nitro radical, dialkylamino radical or halogen, and n is an integer of 1, 2 or 3, R may be either identical or different when n is an integer of 2 or 3)]; a process for the preparation of said trisazo compounds; and electrophotographic sensitive materials having a high sensitivity as well as a high flexibility which comprise a conductive support and a photosensitive layer containing a trisazo compound, as an effective ingredient thereof, which is expressed by the general formula II ##STR3## [wherein A' represents ##STR4## (wherein Z represents aromatic rings such as benzene ring, naphthalene ring, etc., hetero rings such as indole ring, carbazole ring, benzofuran ring, etc. or their substituents, Ar.sub.1 represents aromatic rings such as benzene ring, naphthalene ring, etc., hetero rings such as dibenzofuran ring, etc.

Abstract: The present invention provides disazo compounds expressed by the general formula I ##STR1## [wherein A represents ##STR2## (wherein R represents alkyl radical, alkoxy radical, nitro radical, dialkylamino radical or halogen, n is 0 or an integer of 1, 2 or 3, and R may be either identical or different when n is an integer of 2 or 3)]; a process for the preparation of said compounds; and electrophotographic sensitive materials having a high sensitivity as well as a high flexibility which comprise a conductive support and a photosensitive layer formed thereon, said photosensitive layer containing a disazo compound, as an effective ingredient, which is expressed by the general formula II ##STR3## [wherein A' represents ##STR4## (wherein X represents aromatic rings such as benzene ring, naphthalene ring, etc., hetero rings such as indole ring, carbazole ring, benzofuran ring, etc. or their substituents, Ar.sub.1 represents aromatic rings such as benzene ring, naphthalene ring, etc.