Glass substrate for magnetic recording medium and method of manufacturing the same
AssigneeHoya Corporation
InventorsXuelu Zou, Hisayoshi Toratani
Life of this patent
Estimating the term…
Abstract
In a glass substrate for use in an information recording medium which is specified by Young's modulus E, the Young's modulus E is determined by the following equation (1) so that the Young's modulus exceeds 90, E=ΣxiρiΣxisi (1) where Si=2NA(Gi/M) (4π/3) (mRA3+nRO3), ρi is the density of component i, NA is the Avogadro's number, Gi is dissociation energy of the component i, Mi is molecular weight of the component i, RA and RO is ionic radius of cation A and anion O of the component i defined by AmOn.
Claims11
A glass substrate for use in an information recording medium which is specified by Young's modulus E, wherein:
- the Young's modulus E is determined by the following equation (1) so that the Young's modulus exceeds 90,
- E=ΣxiρiΣxiSi (1)
- where
- Si=2NA(Gi/M) (4π/3)mRA3+nRO3), and where:
- ρi is the density of component i of glass in g/cm3,
- NA is the Avogadro's number 6.023×1023 ions/mol,
- Gi is the dissociation energy per unit volume of the component i of the glass in kcal/cm3,
- Mi is molecular weight of the component i of the glass in g/mol,
- RA and RO are the ionic radius of cation A and anion O of the component i defined by AmOn in units of 10−8 cm.
A method of manufacturing a glass substrate for use in an information recording medium which is specified by Young's modulus E, comprising the step of:
- selecting composition of said glass substrate so that the Young's modulus E is determined by the following equation (1) and the Young's modulus exceed 90,
- E=ΣxiρiΣxiSi (1)
- where Si=2NA(Gi/M) (4π/3) (mRA3+nRO3), ρi is density of component i, NA is the Avogadro's number, Gi is dissociation energy of the component i, Mi is molecular weight of the component i, RA and RO is ionic radius of cation A and anion O of the component i defined by AmOn.
A device for calculating Young's modulus of a glass substrate for use in an information recording medium, comprising:
- input means for inputting ρi (density of component i), NA (the Avogadro's number), Gi (dissociation energy of the component i), Mi (molecular weight of the component i), RA and RO (ionic radius of cation A and anion O of the component i defined by AmOn) as parameters;
- calculating means for calculating the Young's modulus of said glass substrate by the use of the following equation (1), based upon the inputted parameters;
- and
- E=ΣxiρiΣxiSi (1)
- where Si=2NA(Gi/M)(4π/3) (mRA3+nRO3)
- outputting means for outputting the calculated Young's modulus.
A method for calculating Young's modulus of a glass substrate for use in an information recording medium, comprising the steps of:
- inputting ρi (density of component i), NA (the Avogadro's number), Gi (dissociation energy of the component i), Mi (molecular weight of the component i), RA and RO (ionic radius of cation A and anion O of the component i defined by AmOn) as parameters;
- calculating the Young's modulus of said glass substrate by the use of the following equation (1), based upon the inputted parameters;
- E=ΣxiρiΣxiSi (1)
- where Si=2NA(Gi/M) (4π/3) (mRA3+nRO3);
- and
- outputting the calculated Young's modulus.
A recording medium for calculating Young's modulus of a glass substrate for use in an information recording medium, said recording medium recording a program to execute the steps of:
- inputting ρi (density of component i), NA (the Avogadro's number), Gi (dissociation energy of the component i), Mi (molecular weight of the component i), RA and RO (ionic radius of cation A and anion O of the component i defined by AmOn) as parameters;
- calculating the Young's modulus of said glass substrate by the use of the following equation (1), based upon the inputted parameters;
- E=ΣxiρiΣxiSi (1)
- where Si=2NA(Gi/M) (4π/3) (mRA3+nRO3);
- and
- outputting the calculated Young's modulus.
A method of estimating Young's modulus of a glass substrate for use in an information recording medium, wherein:
- the Young's modulus E is determined by the following equation (1) so that the Young's modulus exceeds 90 without practically manufacturing said glass substrate,
- E=ΣxiρiΣxiSi (1)
- where Si=2NA(Gi/M) (4π/3) (mRA3+nRO3), ρi is density of component i, NA is the Avogadro's number, Gi is dissociation energy of the component i, Mi is molecular weight of the component i, RA and RO is ionic radius of cation A and anion O of the component i defined by AmOn.
A method of estimating Young's modulus of a glass substrate for use in an information recording medium, wherein:
- the Young's modulus E is determined by the following equation (1) so that the Young's modulus exceeds 90 without practically measuring specific gravity of said glass substrate,
- E=ΣxiρiΣxiSi (1)
- where Si=2NA(Gi/M) (4π/3) (mRA3+nRO3), ρi is density of component i, NA is the Avogadro's number, Gi is dissociation energy of the component i, Mi is molecular weight of the component i, RA and RO is ionic radius of cation A and anion O of the component i defined by AmOn.
Dependencies are inferred from the claim text.