US4647473A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for forming protective layer on a flexible magnetic disc sheet
Assignee: Fujifilm Holdings Corp
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Filing: 1984-10-09
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Granted: 1987-03-03
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Expires: 2004-10-09
Abstract
Abstract A method for forming protective layer on a surface portion surrounding the edge of a central aperture of a flexible magnetic disc sheet is described, comprising providing a radiation polymerizable composition on a surface portion surrounding the edge of the central aperture of the flexible magnetic disc sheet by screen printing, and hardening the composition by exposure to radiation; a flexible magnetic disc is also described, wherein a protective layer by the foregoing method is provided, with said protective layer having an inner diameter larger than the diameter of the aperture of the disc sheet and an outer diameter smaller than the diameter of the aperture of a jacket enclosing the disc sheet.
Inventors
- 👤 Mikihiko Kato
- 👤 Shigeo Komine
- 👤 Kazuhiko Morita
- 👤 Yasutoshi Okuzawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:50
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/72; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/24; Y10T428/24273; Y10T428/24322; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/24975
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
114 words
A method for forming a protective layer only on the surface portion surrounding the edge of a central aperture of a flexible magnetic disc sheet, comprising providing a radiation polymerizable composition only on the surface portion surrounding the edge of the central aperture of the flexible magnetic disc sheet by screen printing, and hardening the composition by exposure to radiation wherein the screen printing is conducted using a squeegee at an angle of from 40° to 60° to apply the radiation polymerizable composition, at a printing speed of from 0.5 to 100 m/min, with a clearance between the printing screen and the flexible magnetic disc sheet of from about 0.5 mm to 3 mm.
Claim 2
Independent Claim
114 words
A method for forming a protective layer only on the surface portion surrounding the edge of a central aperture of a flexible magnetic disc sheet, comprising providing a radiation polymerizable composition only on the surface portion surrounding the edge of the central aperture of the flexible magnetic disc sheet by screen printing, and hardening the composition by exposure to radiation wherein the screen printing is conducted using a squeegee at an angle of from 40° to 60° to apply the radiation polymerizable composition, at a printing speed of from 0.5 to 100 m/min, with a clearance between the printing screen and the flexible magnetic disc sheet of from about 0.5 mm to 3 mm.
Claim 3
Dependent Claim
21 words
A method as in claim 1, wherein the screen printing is conducted using a screen of from 200 to 500 mesh.
Claim 4
Dependent Claim
21 words
A method as in claim 1, wherein the screen printing is conducted using a screen of from 270 to 380 mesh.
Claim 5
Dependent Claim
58 words
A method as in claim 1, wherein the screen printing is conducted using a squeegee at an angle of from 45° to 60° to apply the radiation polymerizable composition, at a printing speed of from 1 to 30 m/min, with a clearance between the printing screen and the flexible magnetic disc sheet of from 1 to 2 mm.
Claim 6
Dependent Claim
58 words
A method as in claim 2, wherein the screen printing is conducted using a squeegee at an angle of from 45° to 60° to apply the radiation polymerizable composition, at a printing speed of from 1 to 30 m/min, with a clearance between the printing screen and the flexible magnetic disc sheet of from 1 to 2 mm.
Claim 7
Dependent Claim
58 words
A method as in claim 3, wherein the screen printing is conducted using a squeegee at an angle of from 45° to 60° to apply the radiation polymerizable composition, at a printing speed of from 1 to 30 m/min, with a clearance between the printing screen and the flexible magnetic disc sheet of from 1 to 2 mm.
Claim 8
Dependent Claim
97 words
A method as in claim 1, wherein said flexible magnetic disk sheet is in a jacket which also has a central aperature layer than the central aperature in the flexible magnetic disk sheet, both aperatures being circular and wherein said radiation polymerization composition is provided in layer form around the aperature in the flexible magnetic disk sheet, the inner diameter of the layer being greater than the diameter of the central aperature in the flexible magnetic disk sheet and the outer diameter of the layer being less than the diameter of the central aperature in the jacket.
Claim 9
Dependent Claim
33 words
A method as in claim 7, wherein the inner diameter of the layer minus the central aperature of the flexible magnetic disk sheet is less than 2 mm and more than 0.5 mm.
Claim 10
Dependent Claim
26 words
A method as in claim 1, wherein the radiation polymerizable composition is provided around the central aperature in a thickness of from 1 to 50 μm.
Claim 11
Dependent Claim
26 words
A method as in claim 1, wherein the radiation polymerizable composition is provided around the central aperature in a thickness of from 2 to 15 μm.
Claim 12
Dependent Claim
26 words
A method as in claim 1, wherein the radiation polymerizable composition is provided around the central aperature in a thickness of from 3 to 7 μm.
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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) | 1990-03-02 | 1990-09-01 | 1991-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-02 | 1994-09-01 | 1995-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-02 | 1998-09-01 | 1999-03-03 | $7700.00 | Window Closed / Lapsed |