MAGNETIC TAPE AND METHOD FOR PRODUCING THE SAME

• US 20100035088A1
• Filed: 08/04/2009
• Published: 02/11/2010
• Est. Priority Date: 08/05/2008
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Hitachi Maxell Limited (Maxell, Ltd.)
• Inventors: INOUE, Tetsutaro
• Granted Patent: US 8,349,475 B2
• Time in Patent Office: Days
• US Class Current: 428/846
• CPC Class Codes: B26D 1/245 for thin material, e.g. for sheets, strips or the like
• CPC Class Codes: B26D 2001/0033 assembled from multiple blades
• CPC Class Codes: B26D 2007/2685 flexible mounting means
• CPC Class Codes: B26D 7/2621 for circular cutters
• CPC Class Codes: B26D 7/2635 for circular cutters
• CPC Class Codes: G11B 5/70 on a base layer
• CPC Class Codes: G11B 5/7026 Radiation curable polymers
• CPC Class Codes: G11B 5/78 Tape carriers
• CPC Class Codes: G11B 5/84 Processes or apparatus specially adapted for manufacturing record carriers
• CPC Class Codes: Y10T 83/0419 By distorting within elastic limit
• CPC Class Codes: Y10T 83/0605 Cut advances across work surface

Abstract

A magnetic tape produced by cutting a magnetic sheet with a wide breadth into a tape having a predetermined width using a cutting device, in which the magnetic sheet has a magnetic layer containing magnetic powder and a binder formed on one surface of a non-magnetic substrate having a thickness of 4 μm or less, and a center line average height (Ra) along a roughness curve of a cut edge of the magnetic tape is from 0.08 to 0.25 μm.

Claims

1. A magnetic tape produced by cutting a magnetic sheet with a wide breadth into a tape with a predetermined width using a cutting device, wherein the magnetic sheet comprises a magnetic layer containing magnetic powder and a binder formed on one surface of a non-magnetic substrate having a thickness of 4 μ

m or less, and wherein a center line average height (Ra) along a roughness curve of a cut edge of the magnetic tape is from 0.08 to 0.25 μ

m.

2. The magnetic tape according to claim 1, further comprising a primer layer containing inorganic powder and a binder between said non-magnetic substrate and said magnetic layer.

3. The magnetic tape according to claim 2, wherein said binder of said primer layer contains an electron radiation curing resin.

4. The magnetic tape according to claim 1, which is used with a linear serpentine type magnetic recording-reproducing system.

5. A process for producing a magnetic tape claimed in any one of claims 1 to 4, said process comprising the step of cutting a magnetic sheet with a wide breadth into a tape with a predetermined width, using a cutting device, wherein

a ratio (Ew/Et) of a Young'"'"'s modulus of the magnetic sheet in the widthwise direction (Ew) to a Young'"'"'s modulus thereof in a lengthwise direction (Et) is from 0.85 to 1.15;

said cutting device comprises a cutting means which has thin blades and thick blades located confronting the thin blades while intermeshing therewith, a feeding means which carries the magnetic sheet to a position between the thin blades and the thick blades, and a take-up means;

a intermeshing depth (L) of the thin blades and the thick blades is from 0.05 to 0.1 mm, and the maximum surface roughness (P−

V) of each of the side faces of the thin blades and the thick blades intermeshing with each other is 0.05 μ

m or less; and

the magnetic sheet is cut into a tape with a predetermined width while being so conveyed that fluctuation of the magnetic sheet in the widthwise direction in the proximity of the cutting means is 100 μ

m or less.