Abstract: The invention provides colored fine resin particles useful as coloring materials for inks which can provide images having good water fastness, weather fastness and rub-off resistance and are excellent in dispersion stability, and a production process thereof. The colored fine resin particles have a structure in which a pigment coated with a water-insoluble resin is encapsulated with a copolymer composed of at least a polymerizable unsaturated monomer and a reactive emulsifier.

Abstract: Disclosed herein is a recording medium comprising a base material, and at least one resin selected from a primary amine resin and a secondary amine resin and a hindered amine compound contained in the base material and/or on the surface of the base material.

Abstract: Aqueous pigment ink and organic pigment powder are used for ink-jet recording to form high quality images. Organic pigment powder is prepared by finely granulating an organic pigment containing anthraquinone as principal ingredient by means of a vapor phase method to such an extent that the produced powder shows a number average particle diameter of primary particles of 10 to 50 nm. An aqueous ink contains such organic pigment powder.

Abstract: The invention provides colored fine resin particles useful as coloring materials for inks which can provide images having good water fastness, weather fastness and rub-off resistance and are excellent in dispersion stability, and a production process thereof. The colored fine resin particles have a structure in which a pigment coated with a water-insoluble resin is encapsulated with a copolymer composed of at least a polymerizable unsaturated monomer and a reactive emulsifier.

Abstract: Aqueous pigment ink and organic pigment powder is used for ink-jet recording to form high quality images. Organic pigment powder is prepared by finely granulating an organic pigment containing anthraquinone as principal ingredient by mean of a vapor phase method to such an extent that the produced powder shows a number average particle diameter of primary particles of 10 to 50 nm. Aqueous ink contains such organic pigment powder.

Abstract: Disclosed herein is a recording medium comprising a base material, and at least one resin selected from a primary amine resin and a secondary amine resin and a hindered amine compound contained in the base material and/or on the surface of the base material.

Abstract: A packaging medium for an electrophotographic photosensitive member contains a conductive material and has a volume resistivity of not more than 10.sup.12 .OMEGA..cm.

Abstract: A photosensitive member for electrophotography comprising: an electroconductive substrate and a photosensitive layer disposed thereon comprising an organic photoconductor is provided. the photosensitive layer contains at least, a compound represented by the following formula (I): ##STR1## wherein X.sub.1 denotes a t-butyl or t-amyl group, and X.sub.2 denotes a hydrogen atom, an alkyl group having 1-10 carbon atoms or an alkenyl group having 2-10 carbon atoms; and a compound represented by the following formula (II): ##STR2## wherein X.sub.3 and X.sub.4 respectively denote an alkyl group having 1-10 carbon atoms or an alkenyl group having 2-10 carbon atoms.

Abstract: An electrophotographic photosensitive member having an electroconductive substrate and a photosensitive layer or layers contains pigment particles of 0.5 .mu. or below in size in an amount of 80% or more in weight or number of the total pigment. The particles of the above-mentioned size distribution are dispersed in a binder.

Abstract: An apparatus for preparing electrophotographic photosensitive members comprises a means for forming a charge generation layer by coating a charge generation layer coating solution containing two or more kinds of charge-generating materials having different maximum absorption wavelengths, wherein the apparatus further comprises a means for measuring absorbance or transmittance at the respective maximum absorption wavelengths of said coating solution to measure the mixing ratio of the respective charge-generating materials, and a means for controlling the mixing ratio by controlling the feed amount of the respective charge-generating materials.

Abstract: An electrophotographic photosensitive member comprises a photosensitive layer containing an organic photoconductor provided on an electroconductive substrate, wherein said photosensitive layer contains a compound represented by the formula (1) shown below in an amount ranging from 0.1 to 10% by weight based on the total weight of the photosensitive layer added;Formula: ##STR1## wherein R represents ##STR2## X.sub.1, X.sub.2 and X.sub.3 each represent hydrogen atom or methyl group, X.sub.4 represents ##STR3## X.sub.5 represents hydrogen atom, an alkyl group or an alkenyl group.

Abstract: A photosensitive member for electrophotography which is excellent in successive copying characteristics as well as mechanical durability is provided. The photosensitive member comprises a photosensitive layer, at least the surface portion of which comprises a lubricant, and a charge-transporting substance having an oxidation potential of 0.6 volt or above.

Abstract: An electrophotographic photosensitive member has a photosensitive layer on an electroconductive support, characterized in that the surface layer contains a fluorine type resin powder and a fluorine type block copolymer.

Abstract: A packaging arrangement and method for the user thereof to protect an electrophotographic photosensitive member which includes a packaging material for covering and protecting the electrophotographic photosensitive member from physical damage and is capable of generating a frictional electrostatic charge of the same polarity as the electrophotographic photosensitive material, whereby the packaging material has a stronger electron acceptor characteristic than the electrophotographic photosensitive material where the electrophotographic photosensitive material possesses a positive charge, and the packaging material has a stronger electron donor characteristic than the electrophotographic photosensitive material where the electrophotographic photosensitive material possesses a negative charge.

Abstract: An electrophotographic photosensitive member is provided which has an electroconductive substrate and a photosensitive layer, said photosensitive layer containing at least one of (I) polymethyl methacrylates having a molecular weight of 28.times.10.sup.4 or lower, preferably 1.0.times.10.sup.4 to 28.times.10.sup.4 and at least one of (II) polymethyl methacrylates having a molecular weight of 50.times.10.sup.4 to 250.times.10.sup.4, preferably 100.times.10.sup.4 to 250.times.10.sup.4, said polymethyl methacrylate (II) being contained at a proportion of 0.1 part by weight to 30 parts by weight in the composition consisting of the polymethyl methacrylates (I) and (II).

Abstract: An electrophotographic photosensitive member comprises a photosensitive layer on an electroconductive substrate, said photosensitive layer containing a polymer formed from a polymerizable monomer having, in the side chain, an aromatic ring substituted with fluorine atom as the constituent.

Abstract: An electrophotographic photosensitive member having a photosensitive layer on an electroconductive substrate comprises a surface layer containing a fluorine type resin powder and a fluorine type graft polymer.

Abstract: The invention provides an electrophotographic photosensitive member having an improved sensitivity and an improved potential stability when repeatedly copied by using a photosensitive layer containing a disazo pigment having a specific molecular structure.

Abstract: An image holding member has a surface layer containing a silicone type comb shaped graft polymer having a silicone portion at the side chain.

Abstract: An electrophotographic photosensitive member has a photosensitive layer in which the surface hardness of the photosensitive layer is 10 g. or more which is a vertical load necessary for forming a scratch of 50 .mu.m wide when the vertical load is applied to a diamond or supphire cone pressing member, the conical angle being 90.degree. and the tip being a semispheric shape having a diameter of 0.01 mm and the cone pressing member is moved on the surface of the photosensitive layer at the speed of 50 mm/min.