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US 11,670,333 B2Granted
Magnetic tape having characterized coefficient of variation of e-iron oxide powder particle size, magnetic tape cartridge, and magnetic recording and reproducing apparatus
AssigneeFUJIFILM Corporation
InventorsTakashi Fujimoto, Norihito Kasada, Eiki Ozawa
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Abstract
The magnetic tape includes a non-magnetic support and a magnetic layer including ferromagnetic powder, in which the ferromagnetic powder is ε-iron oxide powder, and a coefficient of variation of particle size of the ε-iron oxide powder in a longitudinal direction of the magnetic layer is 0.50% or more and 5.00% or less.
Claims19
A magnetic tape comprising:
- a non-magnetic support;
- and
- a magnetic layer including ferromagnetic powder,
- wherein the ferromagnetic powder is ε-iron oxide powder,
- a coefficient of variation of particle size of the ε-iron oxide powder in a longitudinal direction of the magnetic layer is 0.55% or more and 5.00% or less, and
- the coefficient of variation of particle size is determined according to the following expression by obtaining an average particle size d of ε-iron oxide powder at each of 50 locations at an interval of 10 cm in the longitudinal direction of the magnetic layer and then obtaining an arithmetic average dA and a standard deviation dD of values of the obtained 50 average particle sizes d's,
- coefficient of variation of particle size=(dD/dA)×100.
4 more elements
Dependencies are inferred from the claim text.