TH24237B - Glass substrate for recording media - Google Patents

Abstract

DC60 in magnetic recording medium, surface roughness of glass substrate. And the transformation of The surface roughness that was inhibited, ie, the surface roughness (Rmax, Ra, Rq) and the relationship (Rmax / Ra) between Rmax and Ra limited by Ra, showed the mean median roughness Rmax. That has been set according to the maximum height That shows the difference between the highest And the lowest point and Rq show the mean square root roughness, hence the small grains of the crystals of the shelf below And magnetic layer That were created equal on it The surface roughness is specifically defined with Rmax less than or equal to 15 nm, Ra less than or equal to 1 nm and Rq less than or equal to 1.5 nm, and the ratio between Rmax face roughness and Ra face roughness ranges from 10 -. 30 In the magnetic log medium, the surface roughness of the glass substrate. And the transformation of The surface roughness was inhibited, ie, the surface roughness (Rmax Ra, Rq) and the correlation (Rmax / Ra) between Rmax and Ra limited by Ra, showing the mean median roughness Rmax at Is defined according to the maximum height That shows the difference between the highest And the lowest point and Rq show the mean square root roughness, hence the small grains of the crystals of the shelf below And magnetic layer That were created equal on it The surface roughness is specifically defined with Rmax less than or equal to 15 nm, Ra less than or equal to 1 nm and Rq less than or equal to 1.5 nm, and the ratio between Rmax face roughness and Ra face roughness ranges from 10-. 30

Claims (3)

1.Glass substrates where for use in the recording medium and where there is a surface roughness Ra, Rmax and Rq, where Ra is shown as the mean linear average roughness, Rmax is defined. Rq is the maximum height that shows the difference between the highest and lowest point, and Rq is shown as the mean square root roughness, where the surface roughness is less determined by Rmax. Or equal to 15 nm, Ra is less than or equal to 1 mm and Rq is less than or equal to 1.5 n m. Rmax / Ra falls within the range between 10 and 30 and surface roughness is measured. By interatomic force microscopes 2. Glass substrates, as herein, in claim 1 where the surface roughness is defined with Rmax less than or equal to 10nm, Ra less than or equal to 0.5 n m. And Rq less than or This is 0.7 nm. 3.Glass substrates, as herein, in claim 1 where the surface roughness is defined with Rmax less than or equal to 5nm, Ra less than or equal to 0.3 n m. And Rq less than or This is equal to 0.4 nm.