Patent ID: 6099954
Filing Date: 2000-08-08
Classification: B24B,B24D,C08K,C08L,Y10T

Abstract:
A polishing pad comprising:a backing layer and affixed to the backing layera polishing layer consisting essentially of an elastomeric polymer having a polishing surface and an open elongated cellular structure including cells which are separated by walls at the polishing surface, the elastomeric polymer being substantially free of non-porous fibrous material adjacent the polishing surface, the walls containing finely divided particulate material having a modulus of rigidity greater than that of the elastomeric polymer and having a hardness of at least 3 on a Mohs scale,wherein the polishing layer contains 1-30% by weight, based on the combined weight of the particulate material and the elastomeric polymer, of finely divided particulate material having an average dimension in the range of 0.01 to 1.0 micron, and the particulate material is selected from the group consisting of silica, alumina, zirconia, ceria, titania, silicon carbide, calcium carbonate, mica, magnesium silicate, glass beads, and combinations thereof; andwherein said elastomeric polymer has a Shore D Hardness in the range of about 20-90, and said cellular structure is substantially free of non-porous fibrous material for a depth of at least 125 microns.