Abstract: A magnetic-disk glass substrate of the present invention has an average value of squares of inclinations of 0.0025 or less and a frequency at which squares of inclinations are 0.004 or more of 15% or less, in a case where samples of inclinations on a main surface are obtained at intervals of 10 nm.

Abstract: A polishing liquid for CMP, comprising: an abrasive grain including a cerium-based compound; a 4-pyrone-based compound; a polymer compound having an aromatic ring and a polyoxyalkylene chain; a cationic polymer; and water.

Abstract: A magnetic disk substrate having a flat main surface, an end face, and a chamfered face formed between the main surface and the end face. The substrate has an offset portion, present on the main surface within a range of 92.0 to 97.0% in a radial direction from a center of the substrate. A distance from the center of the substrate to the end face of the substrate in a radial direction is 100%, the offset portion being raised or lowered with respect to a virtual straight line connecting two points on the main surface, set at positions of 92.0% and 97.0%. A maximum distance from the virtual straight line to the offset portion in a direction perpendicular to the virtual straight line is a “maximum offset value.

Abstract: A magnetic disk substrate having a flat main surface, an end face, and a chamfered face formed between the main surface and the end face. The substrate has an offset portion, present on the main surface within a range of 92.0 to 97.0% in a radial direction from a center of the substrate. A distance from the center of the substrate to the end face of the substrate in a radial direction is 100%, the offset portion being raised or lowered with respect to a virtual straight line connecting two points on the main surface, set at positions of 92.0% and 97.0%. A maximum distance from the virtual straight line to the offset portion in a direction perpendicular to the virtual straight line is a “maximum offset value.

Abstract: A magnetic-disk glass substrate of the present invention has an average value of squares of inclinations of 0.0025 or less and a frequency at which squares of inclinations are 0.004 or more of 15% or less, in a case where samples of inclinations on a main surface are obtained at intervals of 10 nm.

Abstract: Provided is a polishing liquid including cerium oxide particles, an organic acid A, a polymer compound B having a carboxyl acid group or a carboxylate group, and water, wherein the organic acid A has at least one group selected from the group consisting of —COOM group, -Ph-OM group, —SO3M group and —PO3M2 group, pKa of the organic acid A is less than 9, a content of the organic acid A is 0.001 to 1 mass % with respect to the total mass of the polishing liquid, and a content of the polymer compound B is 0.01 to 0.50 mass % with respect to the total mass of the polishing liquid, and pH is in the range of 4.0 to 7.0.

Abstract: A magnetic-disk glass substrate of the present invention has an average value of squares of inclinations of 0.0025 or less and a frequency at which squares of inclinations are 0.004 or more of 15% or less, in a case where samples of inclinations on a main surface are obtained at intervals of 10 nm.

Abstract: Provided is a polishing liquid including cerium oxide particles, an organic acid A, a polymer compound B having a carboxyl acid group or a carboxylate group, and water, wherein the organic acid A has at least one group selected from the group consisting of —COOM group, -Ph-OM group, —SO3M group and —PO3M2 group, pKa of the organic acid A is less than 9, a content of the organic acid A is 0.001 to 1 mass % with respect to the total mass of the polishing liquid, and a content of the polymer compound B is 0.01 to 0.50 mass % with respect to the total mass of the polishing liquid, and pH is in the range of 4.0 to 7.0.

Abstract: A polishing liquid for CMP, comprising: an abrasive grain including a cerium-based compound; a 4-pyrone-based compound; a polymer compound having an aromatic ring and a polyoxyalkylene chain; a cationic polymer; and water.

Abstract: A magnetic disk substrate having a flat main surface, an end face, and a chamfered face formed between the main surface and the end face. The substrate has an offset portion, present on the main surface within a range of 92.0 to 97.0% in a radial direction from a center of the substrate. A distance from the center of the substrate to the end face of the substrate in a radial direction is 100%, the offset portion being raised or lowered with respect to a virtual straight line connecting two points on the main surface, set at positions of 92.0% and 97.0%. A maximum distance from the virtual straight line to the offset portion in a direction perpendicular to the virtual straight line is a “maximum offset value.

Abstract: A magnetic disk substrate having a flat main surface, an end face, and a chamfered face formed between the main surface and the end face. The substrate has an offset portion, present on the main surface within a range of 92.0 to 97.0% in a radial direction from a center of the substrate. A distance from the center of the substrate to the end face of the substrate in a radial direction is 100%, the offset portion being raised or lowered with respect to a virtual straight line connecting two points on the main surface, set at positions of 92.0% and 97.0%. A maximum distance from the virtual straight line to the offset portion in a direction perpendicular to the virtual straight line is a “maximum offset value.

Abstract: A magnetic-disk glass substrate of the present invention has an average value of squares of inclinations of 0.0025 or less and a frequency at which squares of inclinations are 0.004 or more of 15% or less, in a case where samples of inclinations on a main surface are obtained at intervals of 10 nm.

Abstract: When mirror polishing is performed on a glass substrate by bringing a polishing pad into contact with the surface of the glass substrate while supplying a polishing liquid containing polishing grains to the substrate surface, the pH of the polishing liquid is maintained within a certain range or the agglomeration degree or dispersion degree of the polishing liquid is controlled. Consequently, an adequate mirror polishing rate can be maintained and there can be obtained a glass substrate having a good end shape.

Abstract: A magnetic disk substrate highly reliable to prevent the occurrence of crash failure even if a magnetic disk is rotated at high speed, and suitable for a hard disk that starts and stops by the load/unload method, and a magnetic disk using such a substrate. The representative structure of the magnetic disk substrate is a disk-shaped glass substrate 10 having a generally flat main surface 11, an end face 12, a chamfered face 13 formed between the main surface 11 and the end face 12, and an offset portion, at the periphery of the main surface 11, raised or lowered with respect to a flat surface, other than the periphery, of the main surface 11, and characterized in that the magnitude of the offset portion is approximately uniform over the entire circumference of the glass substrate 10.

Abstract: It is an object to provide a magnetic disk substrate highly reliable to prevent the occurrence of crash failure even if a magnetic disk is rotated at high speed, and suitable for a hard disk that starts and stops by the load/unload method, and a magnetic disk using such a substrate. The representative structure of a magnetic disk substrate is a disk-shaped glass substrate 10 having a generally flat main surface 11, an end face 12, a chamfered face 13 formed between the main surface 11 and the end face 12, and an offset portion, at the periphery of the main surface 11, raised or lowered with respect to a flat surface, other than the periphery, of the main surface 11, and characterized in that the magnitude of the offset portion is approximately uniform over the entire circumference of the glass substrate 10.

Abstract: When mirror polishing is performed on a glass substrate by bringing a polishing pad into contact with the surface of the glass substrate while supplying a polishing liquid containing polishing grains to the substrate surface, the pH of the polishing liquid is maintained within a certain range or the agglomeration degree or dispersion degree of the polishing liquid is controlled. Consequently, an adequate mirror polishing rate can be maintained and there can be obtained a glass substrate having a good end shape.

Abstract: When mirror polishing is performed on a glass substrate by bringing a polishing pad into contact with the surface of the glass substrate while supplying a polishing liquid containing polishing grains to the substrate surface, the pH of the polishing liquid is maintained within a certain range or the agglomeration degree or dispersion degree of the polishing liquid is controlled. Consequently, an adequate mirror polishing rate can be maintained and there can be obtained a glass substrate having a good end shape.

Abstract: Provided is a polishing liquid including cerium oxide particles, an organic acid A, a polymer compound B having a carboxyl acid group or a carboxylate group, and water, wherein the organic acid A has at least one group selected from the group consisting of —COOM group, -Ph-OM group, —SO3M group and —PO3M2 group, pKa of the organic acid A is less than 9, a content of the organic acid A is 0.001 to 1 mass % with respect to the total mass of the polishing liquid, and a content of the polymer compound B is 0.01 to 0.50 mass % with respect to the total mass of the polishing liquid, and pH is in the range of 4.0 to 7.0.

Abstract: It is an object to provide a magnetic disk substrate highly reliable to prevent the occurrence of crash failure even if a magnetic disk is rotated at high speed, and suitable for a hard disk that starts and stops by the load/unload method, and a magnetic disk using such a substrate. The representative structure of a magnetic disk substrate according to this invention is a disk-shaped glass substrate 10 having a generally flat main surface 11, an end face 12, a chamfered face 13 formed between the main surface 11 and the end face 12, and an offset portion, at the periphery of the main surface 11, raised or lowered with respect to a flat surface, other than the periphery, of the main surface 11, and characterized in that the magnitude of the offset portion is approximately uniform over the entire circumference of the glass substrate 10.

Abstract: It is an object to provide a magnetic disk substrate highly reliable to prevent the occurrence of crash failure even if a magnetic disk is rotated at high speed, and suitable for a hard disk that starts and stops by the load/unload method, and a magnetic disk using such a substrate. The representative structure of a magnetic disk substrate according to this invention is a disk-shaped glass substrate 10 having a generally flat main surface 11, an end face 12, a chamfered face 13 formed between the main surface 11 and the end face 12, and an offset portion, at the periphery of the main surface 11, raised or lowered with respect to a flat surface, other than the periphery, of the main surface 11, and characterized in that the magnitude of the offset portion is approximately uniform over the entire circumference of the glass substrate 10.