Patent ID: 9186771
Filing Date: 2015-11-17
Classification: B08B,B24B,C09G,C09K,G11B

Abstract:
1. A method of manufacturing a glass substrate for a magnetic disk, comprising: polishing a main surface of the glass substrate using a polishing liquid containing colloidal silica abrasive particles as polishing abrasive particles and a surface plate with a polishing pad, bringing the glass substrate into contact with a liquid containing a coagulant to coagulate the colloidal silica abrasive particles adhered to the glass substrate and to thereby form an aggregate of the colloidal silica abrasive particles, and then removing the aggregate of the colloidal silica abrasive particles from the glass substrate by ultrasonic cleaning, wherein; the polishing liquid with the colloidal silica abrasive particles is adjusted to an acidic pH value, the liquid with the coagulant has a neutral to acidic pH range, the coagulant is a carboxylic acid coagulant which serves as a binder for the colloidal silica abrasive particles, and the coagulant contains at least one selected from the group consisting of lactic acid, salicylic acid, and malic acid.