Abstract: The present invention provides an azo pigment comprising a group represented by the general formula (1) below, an electrophotographic photosensitive member comprising an intermediate layer comprising the azo pigment, and a process cartridge and an electrophotographic apparatus that comprise the electrophotographic photosensitive member.

Abstract: A polyazo compound or salt thereof of the following formula (I): wherein, A represents a naphthyl having 1 to 3 sulfos or a phenyl having 1 to 2 hydrophilic groups selected from sulfo and carboxyl and optionally having a lower alkyl or lower alkoxy, B represents —NHCO— or —N═N—, n represents 0 or 1, R1 to R6 represent hydrogen, lower alkyl or lower alkoxy, R7 represents hydrogen or sulfo, D represents —N═N— when B is —N═N— and represents —NHCO—, —N═N— or —NH— when E is —NHCO—, and E represents a phenyl optionally having 1 to 3 groups selected from hydroxyl, amino, nitro, sulfo, carboxyl, lower alkyl and lower alkoxy; and a dye-based polarization film which manifests high polarization ability, is excellent in durability and light resistant to exposure for a long period of time and is obtainable by adding the above polyazo compound or salt thereof; are provided.

Abstract: A trisazo compound represented by the following formula (I) in the free acid form: ##STR1## wherein Q is an phenyl or naphthyl group both of which may be unsubstituted or substituted; one of the A and B is hydroxy group and the other is amino group; K is 1 or 2; and one of m and n is 1 and the other is 0; a method for dyeing fiber materials, paper or leather by using the trisazo compounds and an ink containing the trisazo compounds, and the trisazo compound is excellent in solubility, and good in storage stability and free from clogging of nozzle caused by deposition. The ink using the trisazo compound gives a deep black-colored image excellent in clarity, water-durability and durability to light.

Abstract: Use of metal complex dyes comprised of metalizable azo compounds to dye metal-tanned leather which makes possible good permeability and excellent color fastness to rubbing and color fastness to light.