Abstract: A polishing pad including a polyurethane sheet as a polishing layer, wherein the polyurethane sheet has a ratio (E?B40/E?T40) of a storage elastic modulus E?B40 at 40° C. in dynamic viscoelasticity measurement performed under a bending mode condition with a frequency of 1.6 Hz to a storage elastic modulus E?T40 at 40° C. in dynamic viscoelasticity measurement performed under a tension mode condition with a frequency of 1.6 Hz of 0.60 to 1.60.

Abstract: Provided is a polishing pad comprising a polishing layer made of a polyurethane resin foam containing an isocyanate-terminated prepolymer, and a curing agent, wherein the ratio (NC80/NC40) of a weight proportion (NC80) of an amorphous phase content in the polishing layer measured at 80° C. by a pulsed NMR method to a weight proportion (NC40) of the amorphous phase content in the polishing layer measured at 40° C. by the pulsed NMR method is between 1.5 and 2.5.

Abstract: A polishing pad comprising a polishing layer that has a polishing surface for performing a polishing process on an item to be polished, wherein the polishing layer includes hollow microspheres that form hollow bodies within the polishing layer, a cross-section of the polishing layer has an average pore diameter of 10-14 ?m, and in a histogram of pore diameters in a cross-section of the polishing layer where the bin width is 1 ?m, the sum of pores that are 25 ?m or greater is 5% or less with respect to the total number of pores in the cross-section, and the sum of the areas of the pores in each bin that is 25 ?m or greater is 20% or less with respect to the total area of the pores in the cross-section.

Abstract: This polishing pad has a polishing layer that comprises a polyurethane resin foam derived from an isocyanate-terminated prepolymer and a curing agent, wherein: the distance between hard segments in the polishing layer as measured by small-angle X-ray scattering is 9.5 nm or less; or the ratio (NC80/CC80) of the content proportion by weight (NC80) of an amorphous phase in the polishing layer as measured by pulse NMR at 80° C. to the content proportion by weight (CC80) of a crystalline phase in the polishing layer as measured by pulse NMR at 80° C. is 2.6-3.1, and the ratio (NC40/CC40) of the content proportion by weight (NC40) of an amorphous phase in the polishing layer as measured by pulse NMR at 40° C. to the content proportion by weight (CC40) of a crystalline phase in the polishing layer as measured by pulse NMR at 40° C. is 0.5-0.9.

Abstract: A polishing pad is equipped with a polishing layer having a polyurethane sheet, wherein a tan ? peak value change rate determined by formula: tan ? peak value change rate=|tan ? peakwet?tan ? peakdry|/tan ? peakdry×100, is not more than 15%, where tan ? peakwet represents the peak value of the loss tangent tan ?, of the polyurethane sheet in a wet state after being immersed in water for three days, within a temperature range of 20-100° C. in a tensile mode under an initial load of 148 g with a strain range of 0.1% at a measurement frequency of 1.6 Hz, and tan ? peakdry represents the peak value of the loss tangent tan ?, of the polyurethane sheet in a dry state without being immersed in water, within a temperature range of 20-100° C. in a tensile mode under an initial load of 148 g with a strain range of 0.1% at a measurement frequency of 1.6 Hz.

Abstract: The present invention relates to a polishing pad including a polishing layer and a cushion layer, wherein a ratio E?B40/E?C40 of a storage elastic modulus at 40° C. in dynamic viscoelasticity measurement performed under a bending mode condition with a dry state, a frequency of 10 rad/s, and 20 to 100° C., E?B40, to a storage elastic modulus at 40° C. in dynamic viscoelasticity measurement performed under a compression mode condition with a dry state, a frequency of 10 rad/s, and 20 to 100° C., E?C40, is 3.0 or more and 15.0 or less, and a loss factor tan ? in the dynamic viscoelasticity measurement performed under the bending mode condition is 0.10 or more and 0.30 or less in a range of 40° C. or more and 70° C. or less.

Abstract: A polishing pad contains: a polishing layer having a polishing surface for polishing a workpiece; and a cushion layer disposed on the side of the polishing layer opposite from the polishing surface. With regard to the ratio (tan?) of the storage elastic modulus E? to the loss elastic modulus E? of the whole polishing pad, as obtained through dynamic viscoelasticity measurement using frequency dispersion (25° C.) in a bending mode, the ratio of the maximum value of tan? measured at 100-1000 rad/s (tan?max100-100) to the maximum value of tan? measured at 1 to 10 rad/s (tan?max1-10) is 0.75 to 1.30.

Abstract: Provided is a polishing unit that can reduce penetration of a polishing slurry into a base material layer and that can prevent impairment in polishing performance. A polishing unit (10a) in accordance with a first aspect of the present invention includes: a polishing pad (100a) that includes a polishing layer (101) and a base material layer (103); and a surface plate (150), the base material layer (103) having a diameter smaller than a diameter of the polishing layer (101) and greater than a diameter of the surface plate (150).

Abstract: A polishing layer having an endpoint detection window is manufactured in the following manner. First, a curing agent and a polymer which form the endpoint detection window are mixed, and then the mixture is poured into a mold to form a columnar material. Next, the roughness of the outer peripheral surface of the columnar material is adjusted, and a plurality of projections and recesses are formed on the outer peripheral surface. Next, in a state where the columnar material is housed in a mold frame, the mixture obtained by mixing the polymer and the curing agent is poured into the mold frame and solidified to create a polyurethane polyurea resin molded article. Next, the polyurethane polyurea resin molded article is horizontally cut with a necessary thickness so as to form a sheet-like member, and the sheet-like member forms a polishing layer having the endpoint detection window.

Abstract: An object is to provide a polishing pad that can reduce generation of scratches, and a method for producing a polished product. A polishing pad including a polyurethane sheet as a polishing layer, wherein the polyurethane sheet exhibits a peak of loss tangent tan ? in the range from 40 to 60° C. in dynamic viscoelasticity measurement performed under conditions of a frequency of 1.6 Hz and a temperature of 20 to 100° C. in a water immersion condition.

Abstract: A polishing pad is equipped with a polishing layer having a polyurethane sheet, wherein a tan ? peak value change rate determined by formula: tan ? peak value change rate=|tan ? peakwet?tan ? peakdry|/tan ? peakdry×100, is not more than 15%, where tan ? peakwet represents the peak value of the loss tangent tan ?, of the polyurethane sheet in a wet state after being immersed in water for three days, within a temperature range of 20-100° C. in a tensile mode under an initial load of 148 g with a strain range of 0.1% at a measurement frequency of 1.6 Hz, and tan ? peakdry represents the peak value of the loss tangent tan ?, of the polyurethane sheet in a dry state without being immersed in water, within a temperature range of 20-100° C. in a tensile mode under an initial load of 148 g with a strain range of 0.1% at a measurement frequency of 1.6 Hz.