Abstract: A cerium salt wherein, when 20 g of the cerium salt is dissolved in a mixed liquid of 12.5 g of 6N nitric acid and 12.5 g of a 30% hydrogen peroxide aqueous solution, a concentration of an insoluble component present in the solution is 5 ppm or less by mass ratio to the cerium salt before dissolution and cerium oxide produced by processing the cerium salt at high temperatures. Scratch on a surface to be polished can be reduced when a cerium based polishing slurry containing the cerium oxide particles is used, since an amount of impurities in cerium oxide particles and cerium salt particles, raw material thereof, is reduced for high purification.

Abstract: A cerium salt wherein, when 20 g of the cerium salt is dissolved in a mixed liquid of 12.5 g of 6N nitric acid and 12.5 g of a 30% hydrogen peroxide aqueous solution, a concentration of an insoluble component present in the solution is 5 ppm or less by mass ratio to the cerium salt before dissolution and cerium oxide produced by processing the cerium salt at high temperatures. Scratch on a surface to be polished can be reduced when a cerium based polishing slurry containing the cerium oxide particles is used, since an amount of impurities in cerium oxide particles and cerium salt particles, raw material thereof, is reduced for high purification.

Abstract: A cerium salt wherein, when 20 g of the cerium salt is dissolved in a mixed liquid of 12.5 g of 6N nitric acid and 12.5 g of a 30% hydrogen peroxide aqueous solution, a concentration of an insoluble component present in the solution is 5 ppm or less by mass ratio to the cerium salt before dissolution and cerium oxide produced by processing the cerium salt at high temperatures. Scratch on a surface to be polished can be reduced when a cerium based polishing slurry containing the cerium oxide particles is used, since an amount of impurities in cerium oxide particles and cerium salt particles, raw material thereof, is reduced for high purification.

Abstract: A facsimile communication system, having a hierarchical system, comprises a central service center as the highest hierarchy, several local service centers as an intermediate hierarchy, plural facsimiles as the lowest hierarchy. The central service center manages the local service centers and fax via the local service centers through a telephone network by the pictorial communication and data communication. A user of a facsimile fills up a support service application by marking YES/NO or wiring desired data. The central service center receives the application and inputs the data to store and send the data to a local service center in charge of the facsimile.

Abstract: An electrophotographic member which can give printed images of high quality and is markedly high in photoresponsiveness can be provided without using halogen solvents by using a composition for charge transport layer which contains a polycarbonate resin having a recurring structural unit represented by the following formula (I) and, if necessary, a specific styryl compound, a specific hydrazone compound and the like: ##STR1## wherein R.sub.1 and R.sub.2 =alkyl, etc.R.sub.3 through R.sub.18 =H, alkyl, etc.k/m=1/1-10/1.

Abstract: A charge transport layer formed from a composition comprising a mixed solvent containing alkoxybenzene and a charge transport material, or a photoconductive layer formed from a composition comprising alkoxybenzene and an organic photoconductive material are effective for producing electrophotographic members excellent in image without damaging the circumstances as well as stable in maintaining good charging characteristics and dark decay characteristics after repeated use.