| 摘要 |
A polishing composition comprising an abrasive, water and an organic acid or a salt thereof, wherein the composition has a specified viscosity of from 1.0 to 2.0 mPa.s at a shearing rate of 1500 s<SUP>-1 </SUP>and 25° C.; a roll-off reducing agent comprising a Brönsted acid or a salt thereof, having an action of lowering viscosity so that the amount of viscosity lowered is 0.01 mPa.s or more, wherein the amount of viscosity lowered is expressed by the following equation: <?in-line-formulae description="In-line Formulae" end="lead"?>(Amount of Viscosity Lowered)=(Viscosity of Standard Polishing Composition)-(Viscosity of Roll-Off Reducing Agent-Containing Polishing Composition),<?in-line-formulae description="In-line Formulae" end="tail"?> wherein the standard polishing composition is prepared which comprises 20 parts by weight of an abrasive, said abrasive being high-purity alumina having Al<SUB>2</SUB>O<SUB>3 </SUB>purity of 98.0% by weight or more composed of alpha-type co-random crystal, 1 part by weight of citric acid, and 79 parts by weight of water; the roll-off reducing agent-containing polishing composition is prepared which comprises 20 parts by weight of an abrasive, said abrasive being high-purity alumina having Al<SUB>2</SUB>O<SUB>3 </SUB>purity of 98.0% by weight or more composed of alpha-type co-random crystal, 1 part by weight of citric acid, 78.9 parts by weight of water and 0.1 parts by weight of a roll-off reducing agent; and the viscosity is a viscosity at a shearing rate of 1500 s<SUP>-1 </SUP>and 25° C. The polishing composition can be favorably used in polishing the substrate for precision parts. |
