POLISHING COMPOSITION AND SUBSTRATE MANUFACTURING METHOD AND POLISHING METHOD

• Main Authors: OSHIMA TAKAHIRO, TAMADA SHUICHI
• Format: Patent
• Language: English; Japanese
• Published: 13.10.2022
• Subjects: ADHESIVES; CHEMISTRY; 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; MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FORELSEWHERE; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; PAINTS; PERFORMING OPERATIONS; PHYSICS; POLISHES; POLISHING; TRANSPORTING

To provide a composition for magnetic disc substrate polishing with favorable initial polishing performance and suppressed secular change in the polishing performance.SOLUTION: A composition for magnetic disc substrate polishing is provided. This polishing composition contains silica particles as abrasive particles and water. The silica particles has an average aspect ratio based on SEM image analysis of 1.1 or more, and the ratio (D99/D90) between a cumulative 99% particle diameter D99 and a cumulative 90% particle diameter D90 in weight-based particle size distribution based on transmissive centrifugal sedimentation is 1.4 or more and the cumulative 90% particle diameter D90 is 250 mm or less.SELECTED DRAWING: None 【課題】初期の研磨性能がよく、かつ該研磨性能の経時変化が抑制された磁気ディスク基板研磨用組成物を提供すること。【解決手段】磁気ディスク基板研磨用組成物が提供される。この研磨用組成物は、砥粒としてのシリカ粒子と、水とを含む。上記シリカ粒子は、ＳＥＭ画像解析に基づく平均アスペクト比が１．１以上であり、光透過式遠心沈降法に基づく重量基準の粒度分布において累積９０％粒子径Ｄ９０に対する累積９９％粒子径Ｄ９９の比（Ｄ９９／Ｄ９０）が１．４以上であり、かつ前記累積９０％粒子径Ｄ９０が２５０ｎｍ以下である。【選択図】なし