Magnetic recording medium

• US 20070009769A1
• Filed: 07/10/2006
• Published: 01/11/2007
• Est. Priority Date: 07/08/2005
• Status: Abandoned Application

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Kanazawa, Minoru
• Application Number:
  US11/482,997
• Publication Number:
  US 20070009769A1
• Time in Patent Office: Days
• US Class Current: 428/845.500
• CPC Class Codes: B26D 1/0006 Cutting members therefor
• CPC Class Codes: B26D 1/245 for thin material, e.g. for sheets, strips or the like
• CPC Class Codes: B26D 2001/0046 rotating continuously about an axis perpendicular to the edge
• CPC Class Codes: B26D 2001/0053 having a special cutting edge section or blade section
• CPC Class Codes: B26D 2001/0093 circular cutting discs with a radiussed blunt cutting edge
• CPC Class Codes: B26D 7/2635 for circular cutters
• CPC Class Codes: G11B 5/70 on a base layer
• CPC Class Codes: G11B 5/735 characterised by the back layer magnetic recording media substrates G11B5/739
• CPC Class Codes: G11B 5/7358 specially adapted for achieving a specific property, e.g. average roughness [Ra]
• CPC Class Codes: G11B 5/78 Tape carriers
• CPC Class Codes: G11B 5/84 Processes or apparatus specially adapted for manufacturing record carriers

Abstract

A magnetic recording medium including a magnetic layer 93 containing ferromagnetic powder and a binder, a support 91, and a backcoat layer 94, provided in this order, and being obtained by slitting to width a magnetic material of broad width and continuous length. The magnetic recording medium has no ridge protruding above the surface plane of the magnetic layer along the slit edge thereof. The magnetic recording medium achieves large recording capacity, is free from the tape pack problems such as appearance of a radial pattern and the output reduction problem, produces no fine scrapings in high speed running, which would cause head clogging and dropouts, thereby exhibiting good running durability and electromagnetic characteristics, and is particularly useful for computer data storage applications.

Claims

1. A magnetic recording medium comprising:

a magnetic layer containing ferromagnetic powder and a binder;

a support; and

a backcoat layer, in this order,

wherein the magnetic recording medium is obtained by slitting to width a magnetic material of broad width and continuous length, and the magnetic recording medium has no ridge formed of the magnetic layer along an edge thereof, the ridge being defined to be a protrusion beyond a surface plane of the magnetic layer.

2. The magnetic recording medium as claimed in claim 1, which has no ridge formed of the backcoat layer along an edge thereof, the ridge being defined to be a protrusion beyond a surface plane of the backcoat layer.

3. The magnetic recording medium as claimed in claim 1, wherein the magnetic layer has a Young'"'"'s modulus of 1000 to 2500 kg/mm² in its thickness direction.

4. The magnetic recording medium as claimed in claim 1, wherein the magnetic layer has a Young'"'"'s modulus of 1250 to 2300 kg/mm² in its thickness direction.

5. The magnetic recording medium as claimed in claim 1, wherein the backcoat layer has a Young'"'"'s modulus of 600 to 2000 kg/mm² in its thickness direction.

6. The magnetic recording medium as claimed in claim 1, wherein the backcoat layer has a Young'"'"'s modulus of 700 to 1800 kg/mm² in its thickness direction.

7. The magnetic recording medium as claimed in claim 1, wherein the support has a Young'"'"'s modulus of 700 to 2000 kg/mm² in its longitudinal direction.

8. The magnetic recording medium as claimed in claim 1, wherein the support has a Young'"'"'s modulus of 933 to 1749 kg/mm² in its longitudinal direction.

9. The magnetic recording medium as claimed in claim 1, further comprising a nonmagnetic layer containing nonmagnetic powder and a binder between the support and the magnetic layer.

10. The magnetic recording medium as claimed in claim 1, wherein the backcoat layer contains a binder, carbon black and inorganic powder having a Mohs hardness of 5 to 9.