Patent ID: 7217179
Filing Date: 2007-05-15
Classification: B24B,B24D

Abstract:
1. A polishing pad having a polishing layer made of a polyurethane or polyurethane-urea, wherein the polyurethane or polyurethane-urea comprises a cured reaction product of a mixture of an isocyanate-terminated urethane prepolymer A and a chain extender B which has two or more active hydrogen-containing groups capable of reacting with an isocyanate group in the molecule and satisfies the following conditions “a” and “b”: the ratio of the storage elastic modulus at 30° C. to the storage elastic modulus at 60° C. of said polishing layer is 2 to 15, and the ratio of the storage elastic modulus at 30° C. to the storage elastic modulus at 90° C. of said polishing layer is 4 to 20.