Abstract: The invention provides an oxo-titanylphthalocyanine crystal which is stable, is superior in dispersibility in a photoreceptive layer and efficiently contributes to improvements in sensitivity and charge retention rate of an electrophotographic photoreceptor when it is used as a charge generating agent, a method for producing the oxo-titanylphthalocyanine crystal, and an electrophotographic photoreceptor.

Abstract: The present invention is to provide a multilayer type electrophotographic photoconductor capable of stably obtaining a high image quality image over a long term by restraining the exposure memory and the photo memory, and an image forming apparatus comprising such a multilayer type electrophotographic photoconductor. A multilayer type electrophotographic photoconductor comprising a charge generating layer containing at least a charge generating agent on a base member directly or via an intermediate layer, and a charge transporting layer containing at least a charge transporting agent and a binder resin formed successively, wherein the light absorption degree at a 680 nm wavelength light beam in the photoconductive layer of the multilayer type electrophotographic photoconductor is of a value of 0.8 or less, and the light absorption degree at a 450 nm wavelength light beam is of a value of 1.

Abstract: Disclosed is an image forming apparatus composed of a combination of multi-layered electrophotographic photoreceptor wherein an undercoat layer is made of at least fine titanium oxide particles and a binder resin and has a thickness of 3 ?m or less and the fine titanium oxide particles are surface treated with alumina and silica and have a number average primary particle size of 20 nm or less, and exposing means by LED exposure. Thus, an electrophotographic photoreceptor having good balance between dispersibility of titanium oxide and electrical insulation properties is obtained and image fog does not occur under high temperature and high humidity environment and also excellent image quality can be maintained during continuous printing under low temperature and low humidity environment.

Abstract: According to the present invention, a titanyl phthalocyanin crystal excellent in storage stability in organic solvents, a method for preparing the same and an electrophotographic photoconductor using the same are provided. In the titanyl phthalocyanin crystal, the method for preparing such a titanyl phthalocyanin crystal and the electrophotographic photoconductor using the same, the titanyl phthalocyanin crystal is characterized by having the maximum peak at a Bragg angle 2?±0.2°=27.2° in a CuK? characteristic X-ray diffraction spectrum and one peak within the range of 270 to 400° C. other than a peak accompanied by the vaporization of adsorbed water in a differential scanning calorimetric analysis.

Abstract: The present invention provides an electrophotographic photoconductor which can reduce the generation of fogging under a high-temperature and high-moisture condition and can be easily manufactured, and a method of manufacturing such an electrophotographic photoconductor. In an electrophotographic photoconductor which includes a support base body, an intermediate layer and a photoconductor layer and a manufacturing method of such an electrophotographic photoconductor, the intermediate layer contains titanium oxide and a binding resin and a ?L value of the intermediate layer satisfies a following relationship formula (1) or a ?A value of the intermediate layer satisfies a following relationship formula (2), that is, ?5.0??L?0 (1) and ?A?0.

Abstract: An electrophotographic photoconductor where generation of cracks, crystallization of a photosensitive layer, and the like occur infrequently by sticking of finger oil. An electrophotographic photoconductor includes a conductive substrate on which a photosensitive layer containing at least a chargegenerating agent, a hole transfer agent and a binding resin is provided, wherein the binding resin is comprised of a plurality of polycarbonate resins; and the photosensitive layer contains a biphenyl derivative as a plasticizer component represented by the following general formula (1). (wherein R1 to R10 each independently represent a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, and R represents a substituted or unsubstituted aryl group having 1 to 12 carbon atoms or a substituted or unsubstituted alkylene group having 1 to 12 carbon atoms).

Abstract: Process for preparing dihydropyridine derivatives and salts and esters thereof represented by the general formula ##STR1## from a phenyl derivative and an enamine derivative in which the phenyl derivative is prepared by reacting a compound of the formula ##STR2## with a compound of the formula ##STR3## in the presence of an aromatic amine selected from o-, m-, p- anisidine; m-, p-toluidine; p-chloroaniline; aniline and o-phenetidine.