Method of Polishing the Inner Peripheral End Surfaces of Substrates for a Recording Medium Using a Brush

Abstract

The object of the invention is to provide a method of polishing the inner peripheral end surfaces of substrates while maintaining a sufficiently high working precision at the time of polishing the inner peripheral end surfaces of a plurality of disk-like substrates for a recording medium. According to the invention, there is provided a method of polishing the inner peripheral end surfaces of disk-like substrates for a recording medium using a brush comprising: providing a plurality of disk-like substrates for a recording medium having a circular hole at the central portion thereof thereby forming an inner peripheral end surface, and stacking them while aligning the circular holes to form an object to be polished having the circular hole at the central portion thereof; bringing a polishing material slurry containing a polishing material into contact with the object to be polished; and inserting a polishing brush having brush hairs studded on the periphery of a rod-like shaft into the circular hole of the object to be polished in a state where the slurry is brought into contact with the object to be polished, and rotating the polishing brush with the shaft as a center axis to polish the inner peripheral end surfaces of the substrates; wherein the polishing material slurry is controlled to remain at a constant temperature.

1 . A method of polishing the inner peripheral end surfaces of disk-like substrates for a recording medium using a brush comprising: 
 providing a plurality of pieces of disk-like substrates for a recording medium having a circular hole at the central portion thereof thereby forming an inner peripheral end surface, and stacking them while aligning the circular holes to form an object to be polished having the circular hole at the central portion thereof;    bringing a polishing material slurry containing a polishing material into contact with said object to be polished;    inserting a polishing brush having brush hairs stud on the periphery of a rod-like shaft into the circular hole of said object to be polished in a state where said slurry is brought into contact with said object to be polished, and rotating the polishing brush with the shaft as a center axis to polish the inner peripheral end surfaces of the substrates;    wherein said polishing material slurry is controlled to remain at a constant temperature.    
   
   
       2 . The method of polishing using a brush according to  claim 1 , wherein the polishing brush is rotated and is reciprocally moved in a direction of inserting the brush relative to the object to be polished to effect the polishing.  
   
   
       3 . A method of producing disk-like substrates for a recording medium including a step of effecting the method of polishing using a brush according to claim.  
   
   
       4 . A substrate produced by the method of producing disk-like substrates for a recording medium of  claim 3 .  
   
   
       5 . A method of producing a magnetic recording medium including a step of effecting the method of polishing using a brush of  claim 1.