Antonelli, Terry, Stout & Kraus, LLP
Glass substrate for a magnetic disk, a magnetic disk which can be formed with a stable texture and a magnetic disk device
A glass substrate for a magnetic disk contains a transition metal. The substrate, which is subjected to formation of zone texturing by irradiating the substrate with a laser beam, has a high mechanical strength even if it is not chemically strengthened. The glass substrate contains a transition metal element and has a transmittance of 10% or less for light in a wavelength range of 300 to 2000 nm. The surface roughness of an information recording surface portion thereof is 2.0 nm or less. In addition to a transition metal element, the glass substrate may include a rare earth metal element.
Hitachi, Ltd.
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G11B G11B G11B
inventional additional inventional
Youichi Akira Hiroki Ken Takashi Noriyuki Kiyoshi Masatomo Takashi Yasutaka
Inomata Kato Yamamoto Takahashi Namekawa Takeo Akamatsu Terakado Naito Suzuki