SILICA ABRASIVE GRAIN, METHOD FOR PRODUCING SILICA ABRASIVE GRAIN AND METHOD FOR PRODUCING GLASS SUBSTRATE FOR MAGNETIC DISK

• Main Author: TOKUMITSU HIDEZO
• Format: Patent
• Language: English; Japanese
• Published: 21.01.2016
• Subjects: ADHESIVES; CHEMISTRY; COMPOUNDS THEREOF; DRESSING OR CONDITIONING OF ABRADING SURFACES; DYES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS; GRINDING; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; INORGANIC CHEMISTRY; MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FORELSEWHERE; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; NON-METALLIC ELEMENTS; PAINTS; PERFORMING OPERATIONS; PHYSICS; POLISHES; POLISHING; TRANSPORTING

PROBLEM TO BE SOLVED: To improve a polishing speed of a glass substrate.SOLUTION: A method for producing a silica abrasive grain comprises a first treatment of reducing a pH of an aqueous solution of silicic acid and heating to a first temperature to subject the silicic acid to condensation polymerization to thereby form a primary particle of silica and a second treatment of newly adding an aqueous solution of silicic acid to the liquid having been subjected to the first treatment, and then heating an aqueous solution including the primary particle and the silicic acid at a second temperature lower than the first temperature to subject the silicic acid to condensation polymerization on the surface of the primary particle to thereby form a silica abrasive grain. 【課題】ガラス基板の研磨速度を向上させる。【解決手段】ケイ酸の水溶液のｐＨを下げるとともに第１の温度に加熱することでケイ酸を縮重合させてシリカの一次粒子を生成する第一の処理と、第一の処理を終えた液に新たにケイ酸の水溶液を加えた後、前記第１の温度よりも低い第２の温度で前記一次粒子およびケイ酸を含む水溶液を加熱して前記一次粒子の表面にケイ酸を縮重合させることで、シリカ砥粒を生成する第二の処理と、を含む、シリカ砥粒の製造方法である。【選択図】 なし