US3916039A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing magnetic recording tape
Assignee: Fujifilm Holdings Corp
•
Filing: 1971-12-15
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Granted: 1975-10-28
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Expires: 1991-12-15
Abstract
Abstract A method of producing a magnetic recording tape comprising the steps of providing a back layer on the back surface of the magnetic tape having a magnetic layer on the surface of a base thereof, said back layer being able to absorb the surface roughness of a roller, and calendering said tape through a space between a metal roller and a nonmetal roller, said nonmetal roller being in contact with said back layer side of said tape.
Inventors
- 👤 Goro Akashi
- 👤 Masaaki Fujiyama
- 👤 Yasuyuki Yamada
- 👤 Koshu Kurokawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:35
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; G11B5/62; G11B5/68; G11B5/70; G11B5/74
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
88 words
A METHOD OF PRODUCING A MAGNETIC RECORDING TAPE HAVING A SMOOTH SURFACE COMPRISING THE STEPS OF PROVIDING A BACK LAYER ON THE BACK SURFACE OF THE MAGMETIC TAPE HAVING A MAGNETIC LAYER ON THE SURFACE OF A BASE THEREOF, SAID BACK LAYER BEING ABLE TO ABSORB THE SURFACE ROUGHNESS OF A ROLLER, AND CALENDERING SAID TAPE THROUGH A SPACE BETWEEN A METAL ROLLER AND A NONMETAL ROLLER, SAID NOMETAL ROLLER BEING IN CONTACT WITH SAID BACK LAYER SIDE OF SAID TAPE WHEREBY SAID TAPE POSSESSES IMPROVED MAGNETIC PROPERTIES.
Claim 2
Independent Claim
88 words
A METHOD OF PRODUCING A MAGNETIC RECORDING TAPE HAVING A SMOOTH SURFACE COMPRISING THE STEPS OF PROVIDING A BACK LAYER ON THE BACK SURFACE OF THE MAGMETIC TAPE HAVING A MAGNETIC LAYER ON THE SURFACE OF A BASE THEREOF, SAID BACK LAYER BEING ABLE TO ABSORB THE SURFACE ROUGHNESS OF A ROLLER, AND CALENDERING SAID TAPE THROUGH A SPACE BETWEEN A METAL ROLLER AND A NONMETAL ROLLER, SAID NOMETAL ROLLER BEING IN CONTACT WITH SAID BACK LAYER SIDE OF SAID TAPE WHEREBY SAID TAPE POSSESSES IMPROVED MAGNETIC PROPERTIES.
Claim 3
Dependent Claim
20 words
Method of producing a magnetic recording tape as defined in claim 1 wherein said back layer is a resilient layer.
Claim 4
Dependent Claim
20 words
Method of producing a magnetic recording tape as defined in claim 1 wherein said back layer is a plastic layer.
Claim 5
Dependent Claim
20 words
Method of producing a magnetic recording tape as defined in claim 1 wherein said back layer is a porous layer.
Claim 6
Dependent Claim
26 words
Method of producing a magnetic recording tape as defined in claim 2 wherein said resilient layer is composed of mixture of carbon black and urethane rubber.
Claim 7
Dependent Claim
24 words
Method of producing a magnetic recording tape as defined in claim 2 wherein said resilient layer is composed of titanium oxide and synthetic rubber.
Claim 8
Dependent Claim
19 words
Method of producing a magnetic recording tape as defined in claim 6 wherein said synthetic rubber is chlorosulfonated polyethylene.
Claim 9
Dependent Claim
25 words
Method of producing a magnetic recording tape as defined in claim 3 wherein said plastic layer is composed of carbon black and ethylenevinyl acetate copolymer.
Claim 10
Dependent Claim
25 words
Method of producing a magnetic recording tape as defined in claim 3 wherein said plastic layer is composed of a graphite particles and thermoplastic polyurethane.
Claim 11
Dependent Claim
30 words
Method of producing a magnetic recording tape as defined in claim 4 wherein said porous layer is composed of carbon black bound by a binder mainly composed of cellulose nitrate.
Claim 12
Dependent Claim
29 words
Method of producing a magnetic recording tape as defined in claim 4 wherein said porous layer is composed of carbon black and a binder mainly composed of linear polyester.
Claim 13
Dependent Claim
26 words
Method of producing a magnetic recording tape as defined in claim 4 wherein said porous layer is composed of titanium oxide and vinyl chloride acetate resin.
Claim 14
Dependent Claim
24 words
Method of producing a magnetic recording tape as defined in claim 4 wherein said porous layer is composed of graphite particles and urea resin.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-27 | 1979-04-28 | 1979-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-27 | 1983-04-28 | 1983-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-27 | 1987-04-28 | 1987-10-28 | $7700.00 | Window Closed / Lapsed |