Magnetic recording medium and magnetic recording and reproducing device
US-2019304498-A1 · Oct 3, 2019 · US
Magnetic recording medium and magnetic recording and reproducing device
US10741208B2 · US · B2
| Field | Value |
|---|---|
| Publication number | US-10741208-B2 |
| Application number | US-201916367918-A |
| Country | US |
| Kind code | B2 |
| Filing date | Mar 28, 2019 |
| Priority date | Mar 29, 2018 |
| Publication date | Aug 11, 2020 |
| Grant date | Aug 11, 2020 |
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- Title
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Abstract
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The magnetic recording medium includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, in which a center line average surface roughness Ra measured regarding a surface of the magnetic layer is 1.0 nm to 1.6 nm, and a difference (S after −S before ) between a spacing S after measured by optical interferometry regarding the surface of the magnetic layer after ethanol cleaning and a spacing S before measured by optical interferometry regarding the surface of the magnetic layer before ethanol cleaning is greater than 0 nm and equal to or smaller than 6.0 nm.
First claim
Opening claim text (preview).
What is claimed is: 1. A magnetic recording medium comprising: a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, wherein a center line average surface roughness Ra measured regarding a surface of the magnetic layer is 1.0 nm to 1.6 nm, and a difference S after −S before between a spacing S after measured by optical interferometry regarding the surface of the magnetic layer after ethanol cleaning and a spacing S before measured by optical interferometry regarding the surface of the magnetic layer before ethanol cleaning is greater than 0 nm and equal to or smaller than 6.0 nm. 2. The magnetic recording medium according to claim 1 , wherein the difference S after −S before is 1.0 nm to 6.0 nm. 3. The magnetic recording medium according to claim 1 , wherein the difference S after −S before is 2.0 nm to 5.0 nm. 4. The magnetic recording medium according to claim 1 , further comprising: a non-magnetic layer including a non-magnetic powder and a binding agent between the non-magnetic support and the magnetic layer. 5. The magnetic recording medium according to claim 1 , further comprising: a back coating layer including a non-magnetic powder and a binding agent on a surface of the non-magnetic support opposite to a surface provided with the magnetic layer. 6. The magnetic recording medium according to claim 1 , which is a magnetic tape. 7. A magnetic recording and reproducing device comprising: a magnetic recording medium; and a magnetic head, wherein the magnetic recording medium is a magnetic recording medium comprising: a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, wherein a center line average surface roughness Ra measured regarding a surface of the magnetic layer is 1.0 nm to 1.6 nm, and a difference S after −S before between a spacing S after measured by optical interferometry regarding the surface of the magnetic layer after ethanol cleaning and a spacing S before measured by optical interferometry regarding the surface of the magnetic layer before ethanol cleaning is greater than 0 nm and equal to or smaller than 6.0 nm. 8. The magnetic recording and reproducing device according to claim 7 , wherein the difference S after −S before is 1.0 nm to 6.0 nm. 9. The magnetic recording and reproducing device according to claim 7 , wherein the difference S after −S before is 2.0 nm to 5.0 nm. 10. The magnetic recording and reproducing device according to claim 7 , wherein the magnetic recording medium further comprises a non-magnetic layer including a non-magnetic powder and a binding agent between the non-magnetic support and the magnetic layer. 11. The magnetic recording and reproducing device according to claim 7 , wherein the magnetic recording medium further comprises a back coating layer including a non-magnetic powder and a binding agent on a surface of the non-magnetic support opposite to a surface provided with the magnetic layer. 12. The magnetic recording and reproducing device according to claim 7 , wherein the magnetic recording medium is a magnetic tape.
Assignees
Inventors
Classifications
- G11B5/70Primary
on a base layer · CPC title
Structure or manufacture of heads, e.g. inductive · CPC title
- G11B5/70684Primary
Ferro-ferrioxydes · CPC title
Tape carriers · CPC title
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Frequently asked questions
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- What does patent US10741208B2 cover?
- The magnetic recording medium includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, in which a center line average surface roughness Ra measured regarding a surface of the magnetic layer is 1.0 nm to 1.6 nm, and a difference (S after −S before ) between a spacing S after measured by optical interferometry regardi…
- Who is the assignee on this patent?
- Fujifilm Corp
- What technology area does this patent fall under?
- Primary CPC classification G11B5/70. Mapped technology areas include Physics.
- When was this patent published?
- Publication date Tue Aug 11 2020 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
- What related patents are in patentsdb?
- We list 8 related publications on this page (citations in our corpus or others sharing the same primary CPC).