Patent ID: 11964360
Assignee: SK ENPULSE CO., LTD.
Field: Machine tools (Mechanical engineering)
Classification: CPC B  H | IPC B

Claim 0:
1. A polishing pad, which comprises:
a polishing layer having a penetrating hole; and
a window inserted in the penetrating hole,
wherein the difference in wet hardness between the window and the polishing layer is 0.1 Shore D to 12 Shore D, and the wet hardness is a surface hardness measured upon immersion in water for 30 minutes,
wherein the polishing layer is formed from a polishing layer composition that comprises a first urethane-based prepolymer, a curing agent, and a foaming agent; and the window is formed from a window composition that comprises a second urethane-based prepolymer and a curing agent, wherein the difference in the content of the unreacted isocyanate groups (NCO) between the first urethane-based prepolymer and the second urethane-based prepolymer is 0.4% by weight to 1.0% by weight, and
wherein the content of the unreacted isocyanate group (NCO) in the first urethane-based prepolymer is 7.5% by weight to 9.5% by weight; and the content of the unreacted isocyanate group (NCO) in the second urethane-based prepolymer is 8.1% by weight to 9.0% by weight.