POLISHING PAD AND MANUFACTURING METHOD OF THE SAME

To provide a polishing pad which has high stability of a temporal polishing rate, and excellent rise performance of the polishing rate, and a manufacturing method of the same.SOLUTION: A polishing pad includes a polyurethane resin sheet formed by a wet type film-forming method, wherein when storage elastic modulus of the polyurethane resin sheet which is exposed in an environment having a temperature of 40°C and a relative humidity of 100% for 48 hours is represented by E' (100%), and storage elastic modulus of the polyurethane resin sheet which is exposed in an environment having a temperature of 40°C and a relative humidity of 50% for 48 hours is represented by E' (50%), a change in the storage elastic modulus represented by the following expression (I) is 5% or more. Expression (I): (E'(50%)-E'(100%))/E'(50%)×100 (provided that storage elastic modulus is a value at 40°C, in strain range of 0.3%, at measurement frequency of 1 Hz, in tensile mode).SELECTED DRAWING: None 【課題】経時的な研磨レートの安定性が高く、また研磨レートの立ち上がり性能に優れた研磨パッド及びその製造方法を提供すること。【解決手段】湿式成膜法により形成されるポリウレタン樹脂シートを含む研磨パッドであって、温度４０℃、相対湿度１００％の環境下に４８時間曝した前記ポリウレタン樹脂シートの貯蔵弾性率をＥ'（１００％）とし、温度４０℃、相対湿度５０％の環境下に４８時間曝した前記ポリウレタン樹脂シートの貯蔵弾性率をＥ'（５０％）とするとき、下記式（Ｉ）で表される貯蔵弾性率の変化が５％以上である、上記研磨パッド：式（Ｉ） (Ｅ'（５０％）－Ｅ'（１００％）)／Ｅ'（５０％）×１００（ただし、貯蔵弾性率は、４０℃、歪範囲０．３％、測定周波数１Ｈｚ、引っ張りモードにおける値である）。【選択図】なし