Polyurethane porous product and manufacturing method thereof and polishing pad having polyurethane porous product

A method for manufacturing a polyurethane porous product, the method comprising the steps of:

• (a) mixing the liquid curing agent that includes an active hydrogen group-containing compound, a silicon-based surfactant that includes a hydroxyl group, water that is a foaming promoter, and an abrasive;
• (b) injecting a non-reactive gas while the above liquid mixture, an isocyanate group end urethane prepolymer and a solid curing agent that includes active hydrogen group-containing compound are agitated and mixed, and mixing them to form the mixture including a non-reactive gas;
• (c) molding a sheet by discharging and injecting the mixture including a non-reactive gas into a mold;
• (d) curing the molded sheet;
• and
• (e) forming a microhole on the cured sheet.