EP1313451B1 — Milled particles

USPTO Abstract

A process for milling a solid substrate in the milling chamber of a dispersion or media mill in the presence of a two or more compositions of milling media bodies is disclosed wherein all milling media bodies contribute to the grinding of the solid substrate and wherein at least one composition of media bodies provides fragments of milling media bodies that are retained with the milled solid substrate particles in the form of a synergetic commixture produced in the milling process. More specifically, a process is disclosed for preparing a synergetic commixture comprising small particles of a solid substrate and small particulates of a first material of a desired size comprising the steps of (a) providing to the milling chamber of a media mill a contents comprising a pre-mix of a solid substrate, a fluid carrier, a plurality of milling bodies of a first material having a fracture toughness Kc1, and a plurality of milling bodies of a second material having a fracture toughness Kc2; (b) operating the media mill to grind the solid substrate and degrade at least a portion of the milling bodies of first material to produce a dispersion in the fluid carrier comprising a synergetic commixture of small particulates of the first material and small particles of the solid substrate having a desired size equal to or less than a size Sp; (c) separating the dispersion from any milling bodies and solid substrate particles having a size larger than Sp; and (d) optionally removing the fluid carrier from the dispersion to form a synergetic commixture free of fluid and comprising the particles and the small particulates, wherein KC2 is greater than KC1.