Sulfonic acid denatured colloidal silicon dioxide

Abstract

The present invention provides a sulfonic acid-modified colloidal silicon dioxide, which has excellent long-term stability of metal adsorption and can suppress the amount of residual abrasive particles on the metal grinding surface after grinding and cleaning. The present invention relates to a sulfonic acid-modified colloidal silica containing silica particles, characterized in that: (1) the silica particles are surface-modified with sulfonic acid groups; (2) the Cu ion adsorption capacity of the silica particles is 5.00 μmol / g to 110.00 μmol / g; (3) the ratio of Cu ion adsorption capacity to S content of the silica particles (Cu ion adsorption capacity (μmol / g) / S content (μmol / g)) is 0.50 or more; and (4) the time-dependent change rate of Cu ion adsorption capacity of the silica particles, as determined by the following method, is 1.30 or less; [Method for determining the time-dependent change rate of Cu ion adsorption capacity of silica particles] The sulfonic acid-modified colloidal silica is left to stand at 25°C for 3 months. The Cu ion adsorption capacity (μmol / g) of silicon dioxide particles before and after settling was measured. The rate of change of Cu ion adsorption capacity over time was calculated using the following formula: (Rate of change of Cu ion adsorption capacity over time) = Cu ion adsorption capacity after settling (μmol / g) / Cu ion adsorption capacity before settling (μmol / g)