Polishing method, polishing device, glass substrate for magnetic recording medium, and magnetic recording medium
AssigneeHoya Corporation
InventorTakemi Miyamoto
Life of this patent
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Abstract
There are disclosed a polishing method and a polishing device in which cleaning of a glass substrate surface can be achieved to a high level. A glass substrate (MD substrate 1) in the shape of a circular disc having a circular hole in a center portion is polished with an abrasive liquid 50 containing free abrasive grains being supplied, and an inner peripheral end surface of the glass substrate is polished using the abrasive liquid containing the free abrasive grains by rotating a rotary brush 4 or a polishing pad in contact with the inner peripheral end surface.
Claims8
A method of manufacturing a glass substrate for a magnetic recording medium, the glass substrate being in the form of a circular disc having a circular hole in a center portion of the disc, wherein an inner peripheral end surface of the glass substrate is polished by following steps:
- supplying an abrasive liquid containing free abrasive grains to the inner peripheral end surface of the glass substrate;
- and
- rotating a polishing brush in contact with the inner peripheral end surface of said glass substrate to perform polishing, wherein said polishing brush is connected to a rotation shaft,
- wherein a plurality of glass substrates are stacked and polished so that the inner peripheral end surfaces of the plurality of glass substrates are simultaneously polished,
- wherein the polishing brush has bristles which are planted in a helical shape on a surface of the rotation shaft, and the rotation shaft is rotated in a direction in which the abrasive liquid is drawn into the circular hole portion of a plurality of stacked glass substrates, and
- wherein the abrasive liquid is supplied from above the stacked glass substrates and toward the inner peripheral end surface of the glass substrates.
A method of manufacturing a magnetic recording medium, Comprising the steps of:
- a)preparing a glass substrate for the magnetic recording medium, the glass substrate being in the form of a circular disc having a circular hole in a center portion of the disc, wherein an inner peripheral end surface of the glass substrate is polished by following steps:
- supplying an abrasive liquid containing free abrasive grains to the inner peripheral end surface of the glass substrate;
- and
- rotating a polishing brush in contact with the inner peripheral end surface of said glass substrate to perform polishing wherein said polishing brush is connected to a rotation shaft,
- wherein a plurality of glass substrates are stacked and polished so that the inner peripheral end surfaces of the plurality of glass substrates are simultaneously polished,
- wherein the polishing brush has bristles which are planted in a helical shape on a surface of the rotation shaft and the rotation shaft is rotated in a direction in which the abrasive liquid is drawn into the circular hole portion of a plurality of stacked lass substrate, and
- wherein the abrasive liquid is supplied from above the stacked glass substrates and toward the inner end surface of the glass substrates;
- and
- b) forming a magnetic recording layer on the glass substrate.
Dependencies are inferred from the claim text.