Polishing pad and method of use

Abstract

A polishing pad has one or more polishing elements made from a hydrogel material having an intrinsic ability to absorb water. The hydrogel material may or may not have micropores, but has a water absorption capability of 4%-60% by weight, a wet tensile strength greater than 1000 psi, a flexural modulus greater than 2000 psi, and a wet Shore D hardness between 25-80, inclusive. The hydrogel material may be made from one or a combination of the following moieties: urethane, alkylene oxides, esters, ethers, acrylic acids, acrylamides, amides, imides, vinylalcohols, vinylacetates, acrylates, methacrylates, sulfones, urethanes, vinylchlorides, etheretherketones, and/or carbonates.

1 . A polishing pad comprising a plurality of polishing elements, said polishing elements backed by a compressible under-foam disposed beneath a guide plate for the polishing elements, said polishing elements made from a hydrogel polymer having an intrinsic ability to absorb water and having no micro-porosity, the hydrogel material having a water absorption capability of 4%-60% by weight, a wet tensile strength greater than 1000 psi, a flexural modulus greater than 2000 psi, and a wet Shore D hardness between 25-80, inclusive. 
     
     
         2 . The polishing pad of  claim 1 , wherein the hydrogel material is made from one or a combination of the following moieties: urethane, alkylene oxides, esters, ethers, acrylic acids, acrylamides, amides, imides, vinylalcohols, vinylacetates, acrylates, methacrylates, sulfones, urethanes, vinyl chlorides, etheretherketones, and/or carbonates. 
     
     
         3 . A polishing pad comprising a plurality of polishing elements, said polishing elements backed by a compressible under-foam disposed beneath a guide plate for the polishing elements, said polishing elements made from a hydrogel material having a water absorption capability of 4%-60% by weight, a microporosity of 1% to 20% by volume, micropores of 20-100 microns, a wet tensile strength greater than 1000 psi, a flexural modulus greater than 2000 psi, and a wet Shore D hardness between 25-80, inclusive. 
     
     
         4 . The polishing pad of  claim 3 , wherein the hydrogel material is made from one or a combination of the following moieties: urethane, alkylene oxides, esters, ethers, acrylic acids, acrylamides, amides, imides, vinylalcohols, vinylacetates, acrylates, methacrylates, sulfones, urethanes, vinylchlorides, etheretherketones, and/or carbonates.