Patent ID: 11883925
Assignee: FUJIBO HOLDINGS, INC.
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC B  C  H | IPC B

Claim 0:
1. A polishing pad comprising a polishing layer including a polyurethane sheet, wherein a rate of change in a tan δ peak value calculated in accordance with the following equation between a loss tangent tan δ peak value (a tan δ peakwet) within a temperature range of 20° C. to 100° C. of the polyurethane sheet in a wet state after immersion in a water bath for 3 days in a tensile mode with an initial load of 148 g, a strain range of 0.1%, and a measurement frequency of 1.6 Hz, and a loss tangent tan δ peak value (a tan δ peakdry) within a temperature range of 20° C. to 100° C. of the polyurethane sheet in a dry state without immersion in the water bath in a tensile mode with an initial load of 148 g, a strain range of 0.1%, and a measurement frequency of 1.6 Hz is 15% or less:

Rate of change in tan δ peak value=|tan δ peakwet−tan δ peakdry|/tan δ peakdry×100.