Metal oxide particles and their manufacturing methods, fillers, components, hardened products and parts

Abstract

This invention provides metal oxide particles that are not prone to interfacial delamination and can produce hardened products with low thermal expansion coefficient, low water absorption rate, and low dielectric loss tangent. A metal oxide particle is formed by coating at least a portion of the surface of an inorganic particle represented by the following formula (1) with at least one compound selected from the group consisting of organosilanes, phosphonic acid compounds, amine compounds, hydroxyl-containing compounds, and hydrosilane compounds. Zn2-xTxP2-yAyO7 …(1) (In formula (1), T contains at least one element selected from Mg, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Co, Cu, Ga, Ge, Zr, Mo, Ag, In, Sn, W, and Bi; A contains at least one element selected from Al, Si, V, and Ge; satisfying 0≦x<2 and 0≦y≦2; except for (x,y)=(0,2))