Glass for magnetic recording medium substrate or for glass spacer to be used in magnetic recording/reproducing device, magnetic recording medium substrate, magnetic recording medium, glass spacer to be used in magnetic recording/reproducing device, and magnetic recording/reproducing device
AssigneeHoya Corporation
InventorsShuzo TOKUMITSU, Kazuaki HASHIMOTO
Life of this patent
Estimating the term…
Abstract
Provided is a glass for a magnetic recording medium substrate or for a glass spacer for a magnetic recording/reproducing device, the glass being an amorphous glass that contains at least Li2O, in which a total content of Na2O and K2O is 0 mol % or more and 6.0 mol % or less, a B2O3 content is 0 mol % or more and 10.0 mol % or less, and a CaO content is 0 mol % or more and 1.0 mol % or less.
Claims29
A glass for a magnetic recording medium substrate or for a glass spacer for a magnetic recording/reproducing device, the glass being an amorphous glass
- wherein a Li2O content is 3.0 mol % or more,
- a total content of Na2O and K2O is 0 mol % or more and 0.5 mol % or less,
- the glass comprises B2O3 and a B2O3 content is 0.5 mol % or less, and
- a CaO content is 0 mol % or more and 0.1 mol % or less,
- a MgO content is 21.7 mol % or more, and
- a TiO2 content is 0 mol % or more and 0.5 mol % or less.
(canceled)
(canceled)
(canceled)
(canceled)
(canceled)
(canceled)
(canceled)
(canceled)
(canceled)
(canceled)
(canceled)
(canceled)
(canceled)
Dependencies are inferred from the claim text.