1. I have a magnetic disc.

2. Magnetic, disc-shaped, analog and digital carriers for images, sound and data

3. Silica, method for producing silica abrasive, and method for producing glass substrate for magnetic disc

4. LG's DVD for example, because it is through the main bearing and the compression of the gravitational force between the magnetic disc to grip, so this problem does not exist.

5. LG's DVD for example, because it is through the main bearing and the compression of the gravitational force between the magnetic disc attached to and so this problem does not exist.

6. An abrasive used for precisely grinding a substrate used in the optics and electronics industries such as a glass substrate of an optical lens, optical disc, magnetic disc, plasma display, liquid crystal, or LSI photomask.