Patent ID: 8153257

Claim:
A capped particle comprising: (i) one or more core particles wherein the core particle is an inorganic particle having a dimension of about 5 μm or less, wherein the one or more core particles includes at least one inorganic particle that is free of phosphorus, sulfur, chlorine, zinc, and nitrogen, or has a total concentration of phosphorus, sulfur, chlorine, zinc, and nitrogen of about 10 mole % or less, based on the total number of moles of atoms in the inorganic particle; and (ii) one or more multi-block copolymers attached to the inorganic particles, wherein the multi-block copolymer comprises a) at least one nonpolar polymer block; b) at least one first polar polymer block; and c) at least one second polar polymer block; wherein the nonpolar polymer block is interposed between the first polar polymer block and the second polar polymer block, the first polar polymer block is attached to the core particle, and at least a portion of the second polar polymer block is not directly attached to the core particle; so that when used in a lubricant to lubricate a metallic surface of a workpiece, the capped particle adheres to the metallic surface of the workpiece.