Abstract: The present invention relates to ceramics and a method for making ceramics having very little dimensional change after sintering and high dimensional accuracies, so that the characteristics of inorganic functional material are fully maintained and utilized. The ceramics of the present invention comprise grains of inorganic functional material and grains of complex oxide. The pores existing between said grains of inorganic functional material are filled with said grains of complex oxide produced by a sintering reaction between an oxidized metal and an inorganic compound.

Abstract: A coating film of a double-layer structure for a recording medium is formed by providing a non-magnetic buffer layer just beneath a magnetic recording layer composed of magnetic hexagonal platelet ferrite particles, wherein the thickness of the magnetic recording layer is 0.1-0.6 .mu.m and the ratio of thickness of the buffer layer to that of the magnetic recording layer is 1:1 to 4:1. This coating film makes it possible to realize the excellent medium surface characteristics that could not be obtained with the conventional techniques and to obtain a high recording density excelling those of the conventional in-plane longitudinal recording media.

Abstract: A magnetic coating composition prepared by a method comprising a wetting step for wetting powder materials including a magnetic powder with a small amount of a solvent in a kneading machine having an agitation means in a closed container, a first kneading step comprising adding an amount of a binder resin and an amount of a solvent to a mixture from the wetting step and mixing and kneading it, a second kneading step comprising continuously adding the solvent till a consumed power of a kneading apparatus reaches maximum, a third kneading step comprising stopping the addition of the solvent at the maximum consumed power and further kneading the mixture, and a dilution step comprising gradually adding the solvent to the mixture while applying shear force, in which composition, the magnetic powder is highly dispersed and which provides a coating type magnetic recording medium having good properties.