Polishing pad
AssigneeToyo Tire & Rubber Co., Ltd.
InventorsAtsushi KAZUNO, Kazuyuki Ogawa, Masahiko Nakamori, Takatoshi Yamada, Tetsuo Shimomura
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Abstract
A polishing pad generates very few scratches on a surface of a polishing object, and is excellent in planarization property. The polishing pad has a high polishing rate and is excellent in planarization property. The polishing pad grooves become very little clogged with abrasive grains or polishing swarf during polishing and, even when continuously used for a long period of time, the polishing rate is scarcely reduced.
Claims2
A process for manufacturing a polishing pad comprising a step (1) of mixing a first component comprising an isocyanate-terminal prepolymer and a second component comprising a chain extender, and curing the mixture to prepare a polyurethane resin foam, wherein the step (1) is a step of adding a silicone-based nonionic surfactant having no hydroxy group to a first component comprising an isocyanate-terminal prepolymer so that an amount of the surfactant becomes 10 to 20% by weight in a polyurethane resin foam, stirring the first component with a non-reactive gas to prepare a bubble dispersion liquid in which the non-reactive gas is dispersed as a fine bubble, mixing a second component comprising a chain extender in the bubble dispersion liquid, and curing the mixture to prepare a polyurethane resin foam, and a high-molecular-weight polyol component which is a raw material component of the isocyanate-terminal prepolymer is a hydrophobic high-molecular-weight polyol having a number average molecular weight of 500 to 850.
Dependencies are inferred from the claim text.