US4661377A
Expired / Lapsed
US
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Process for producing a magnetic recording medium having an improved dimensional stability
Assignee: Fujifilm Holdings Corp
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Filing: 1984-01-11
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Granted: 1987-04-28
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Expires: 2004-01-11
Abstract
Abstract A heat-treating process is disclosed. The process involves cutting a polymer support for a recording medium from a web roll of a long support base into a sheet form. The sheet or sheets in a superposed state are then heat-treated while applying pressure in the range of 1 g/cm 2 to 1 kg/cm 2 at a temperature of 50° C. to 150° C. for a period of time of 15 seconds to 24 hours. The heat treating process avoids conventional problems with respect to thermal shrinkage.
Inventors
- 👤 Kazuhiko Morita
- 👤 Shigeo Komine
- 👤 Akira Kasuga
- 👤 Noburo Hibino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:32
CPC Classifications
B; B29; B29C; B29C71/00; B29C71/02; B29D; B29D17/00; B29D17/005; G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/739; G11B5/73923; G11B5/73927; G11B5/84
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
84 words
A heat-treating process, comprising the steps of: cutting a polymer support base for a recording medium from a web roll of a long support base into a sheet form; and heat-treating the sheet form under pressure, whereby said sheet form exhibits improved dimensional stability, the heat-treating being carried out at a temperature in the range of 50° C. to 150° C. under a pressure in the range of 1 g/cm 2 to 1 kg/cm 2 , wherein the polymer support base is polyethylene terephthalate.
Claim 2
Dependent Claim
84 words
A heat-treating process, comprising the steps of: cutting a polymer support base for a recording medium from a web roll of a long support base into a sheet form; and heat-treating the sheet form under pressure, whereby said sheet form exhibits improved dimensional stability, the heat-treating being carried out at a temperature in the range of 50° C. to 150° C. under a pressure in the range of 1 g/cm 2 to 1 kg/cm 2 , wherein the polymer support base is polyethylene terephthalate.
Claim 3
Dependent Claim
25 words
A heat-treating process as claimed in claim 1, further comprising the step of: coating a magnetic recording layer on the sheet form after the heat-treating.
Claim 4
Dependent Claim
20 words
A heat-treating process as claimed in claim 2, wherein said magnetic recording layer comprises a polymeric binder and magnetic particles.
Claim 5
Dependent Claim
18 words
A heat-treating process as claimed in claim 2, wherein the magnetic recording layer remains on the sheet form.
Claim 6
Dependent Claim
30 words
A heat-treating process as claimed in claim 1, further comprising the step of: coating a magnetic recording layer on the sheet form after the cutting and prior to the heat-treating.
Claim 7
Dependent Claim
20 words
A heat-treating process as claimed in claim 3, wherein said magnetic recording layer comprises a polymeric binder and magnetic particles.
Claim 8
Dependent Claim
19 words
A heat-treating process as claimed in claim 5, wherein the magnetic recording layer is dried prior to the heat-treating.
Claim 9
Dependent Claim
27 words
A heat-treating process as claimed in claim 1, further comprising the step of: coating a magnetic recording layer on the polymer support base prior to the cutting.
Claim 10
Dependent Claim
20 words
A heat-treating process as claimed in claim 8, wherein said magnetic recording layer comprises a polymeric binder and magnetic particles.
Claim 11
Dependent Claim
19 words
A heat-treating process as claimed in claim 8, wherein the magnetic recording layer remains on the polymer support base.
Claim 12
Dependent Claim
24 words
A heat-treating process as claimed in claim 8, wherein the magnetic recording layer is dried prior to the cutting and prior to the heat-treating.
Claim 13
Dependent Claim
23 words
A heat-treating process as claimed in claim 1, wherein the pressure is applied by two plates between which the sheet form is placed.
Claim 14
Dependent Claim
15 words
A heat-treating process as claimed in claim 1, wherein the sheet form is in disc-form.
Claim 15
Dependent Claim
17 words
A heat-treating process as claimed In claim 1, wherein the heat-treating is between two heated metal plates.
Claim 16
Dependent Claim
20 words
A heat-treating process as claimed in claim 1, wherein the sheet form is a square form or a circular form.
Claim 17
Dependent Claim
24 words
A heat-treating process as claimed in claim 1, wherein the sheet form has a size slightly larger than that of the final product desired.
Claim 18
Dependent Claim
20 words
A heat-treating process as claimed in claim 1, wherein the sheet form is square and 9 inches×9 inches in dimension.
Claim 19
Dependent Claim
87 words
A heat-treating process, comprising the steps of: cutting a polymer support base for recording medium from a web roll of a long support base into a sheet form; and heat-treating the sheet form, the heat-treating being carried out at a temperature in the range of 50° C. to 150° C. under a pressure in the range of 1 g/cm 2 to 1 kg/cm 2 for a period of time in the range of 15 seconds to 24 hours, and wherein said polymer support base is polyethylene terephthalate.
Claim 20
Dependent Claim
87 words
A heat-treating process, comprising the steps of: cutting a polymer support base for recording medium from a web roll of a long support base into a sheet form; and heat-treating the sheet form, the heat-treating being carried out at a temperature in the range of 50° C. to 150° C. under a pressure in the range of 1 g/cm 2 to 1 kg/cm 2 for a period of time in the range of 15 seconds to 24 hours, and wherein said polymer support base is polyethylene terephthalate.
Claim 21
Dependent Claim
25 words
A heat-treating process as claimed in claim 18, further comprising the step of: coating a magnetic recording layer on the sheet form after the heat-treating.
Claim 22
Dependent Claim
20 words
A heat-treating process as claimed in claim 19, wherein said magnetic recording layer comprises a polymeric binder and magnetic particles.
Claim 23
Dependent Claim
30 words
A heat-treating process as claimed in claim 18, further comprising the step of: coating a magnetic recording layer on the sheet form after the cutting and prior to the heat-treating.
Claim 24
Dependent Claim
20 words
A heat-treating process as claimed in claim 21, wherein said magnetic recording layer comprises a polymeric binder and magnetic particles.
Claim 25
Dependent Claim
19 words
A heat-treating process as claimed in claim 21, wherein the magnetic recording layer is dried prior to the heat-treating.
Claim 26
Dependent Claim
27 words
A heat-treating process as claimed in claim 18, further comprising the step of: coating a magnetic recording layer on the polymer support base prior to the cutting.
Claim 27
Dependent Claim
20 words
A heat-treating process as claimed in claim 24, wherein said magnetic recording layer comprises a polymeric binder and magnetic particles.
Claim 28
Dependent Claim
24 words
A heat-treating process as claimed in claim 24, wherein the magnetic recording layer is dried prior to the cutting and prior to the heat-treating.
Claim 29
Dependent Claim
17 words
A heat-treating process as claimed in claim 18, wherein the heat-treating is between two heated metal plates.
Claim 30
Dependent Claim
20 words
A heat-treating process as claimed in claim 18, wherein the sheet form is a square form or a circular form.
Claim 31
Dependent Claim
24 words
A heat-treating process as claimed in claim 18, wherein the sheet form has a size slightly larger than that of the final product desired.
Claim 32
Dependent Claim
20 words
A heat-treating process as claimed in claim 18, wherein the sheet form is square and 9 inches×9 inches in dimension.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-27 | 1990-10-27 | 1991-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-27 | 1994-10-27 | 1995-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-27 | 1998-10-27 | 1999-04-28 | $7700.00 | Window Closed / Lapsed |