US4680225A
Expired / Lapsed
US
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Magnetic tape having a leader tape
Assignee: Fujifilm Holdings Corp
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Filing: 1985-07-01
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Granted: 1987-07-14
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Expires: 2005-07-01
Abstract
Abstract A magnetic tape having a leader tape excellent in cleaning effect as well as antistatic effect and free from head clogging is provided comprising a coating layer provided on one or both sides of a support, at at least one end of the magnetic tape, in which the coating layer contains, as predominant components, an electrically conductive powder and a binder and the leader tape has a percent photo-transmission of at least 20%.
Inventors
- 👤 Hiroshi Ogawa
- 👤 Chiaki Mizuno
- 👤 Yasuo Tamai
- 👤 Koozi Kamiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:00
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/627; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265; Y10T428/31504; Y10T428/31786; Y10T428/31855
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
113 words
A magnetic tape having a leader tape comprising a coating layer provided on one or both sides of a support at least one end of said magnetic tape, characterized in that the coating layer contains, as predominant components, an electrically conductive powder having a mean grain size of 0.001 to 1 um and a volume resistance of 10 0 to 10 8 Ω-cm and being at least one member selected from the group consisting of SnO 2 , In 2 O 3 , ZnO, BaTiO 3 , and SrTiO 3 which have been modified to provide electrical conductivity and a binder and the leader tape has a percent photo-transmission of at least 20%.
Claim 2
Dependent Claim
113 words
A magnetic tape having a leader tape comprising a coating layer provided on one or both sides of a support at least one end of said magnetic tape, characterized in that the coating layer contains, as predominant components, an electrically conductive powder having a mean grain size of 0.001 to 1 um and a volume resistance of 10 0 to 10 8 Ω-cm and being at least one member selected from the group consisting of SnO 2 , In 2 O 3 , ZnO, BaTiO 3 , and SrTiO 3 which have been modified to provide electrical conductivity and a binder and the leader tape has a percent photo-transmission of at least 20%.
Claim 3
Dependent Claim
59 words
The magnetic tape having a leader tape as claimed in claim 1, wherein the electrically conductive powder is at least one member selected from the group consisting of SnO 2 , In 2 O 3 , BaTiO 3 , SrTiO 3 and (Ba, Sr) TiO 3 which are doped with an element of different valence to increase the conductivity.
Claim 4
Dependent Claim
41 words
The magnetic tape having a leader tape as claimed in claim 1, wherein the electrically conductive powder powder is at least one member selected from the group consisting of ZnO, BaTiO 3 and SrTiO 3 into which oxygen defects are introduced.
Claim 5
Dependent Claim
39 words
The magnetic tape having a leader tape as claimed in claim 1, wherein the electrically conductive powder is at least one member of white pigments and extenders which are coated with at least one member of electrically conductive materials.
Claim 6
Dependent Claim
75 words
The magnetic tape having a leader tape as claimed in claim 4, wherein the electrically conductive materials are SnO 2 , In 2 O 3 , ZnO, BaTiO 3 and SrTiO 3 which have electrical conductivity, SnO 2 , In 2 O 3 , BaTiO 3 , SrTiO 3 and (Ba, Sr)TiO 3 which are doped with an element of different valence, and ZnO, BaTiO 3 and SrTiO 3 into which oxygen defects are introduced.
Claim 7
Dependent Claim
35 words
The magnetic tape having a leader tape as claimed in claim 1, wherein the binder is in a proportion of 15 l to 600 parts by weight to 100 parts by weight of the powders.
Claim 8
Dependent Claim
27 words
The magnetic tape having a leader tape as claimed in claim 1, wherein the support is a non-magnetic flexible support having a haze of at most 80%.
Claim 9
Dependent Claim
40 words
The magnetic tape having a leader tape as claimed in claim 1, wherein the binder is at least one member selected from the group consisting of vinyl chloride-vinyl acetate copolymers, vinylidene chloride copolymers, nitrocellulose, polyester resins, polyurethane resins and polyisocyanates.
Claim 10
Dependent Claim
24 words
The magnetic tape having a leader tape as claimed in claim 1, wherein the coating layer has a thickness of 0.05 to 20 um.
Claim 11
Dependent Claim
123 words
A magnetic tape having a leader tape comprising a coating layer provided on one or both sides of a support, at at least one end of the tape, characterized in that the coating layer contains, as predominant components, an electrically conductive powder having a mean grain size of 0.001 to 1 um and a volume resistance of 10 0 to 10 8 Ω-cm and being at least one member selected from the group consisting of SnO 2 , In 2 O 3 , ZnO, BaTiO 3 , and SrTiO 3 which have electrically conductivity, a white inorganic powder having a particle size range of 0.01 to 5 um and a binder and the leader tape has a percent photo-transmission of at least 20%.
Claim 12
Dependent Claim
123 words
A magnetic tape having a leader tape comprising a coating layer provided on one or both sides of a support, at at least one end of the tape, characterized in that the coating layer contains, as predominant components, an electrically conductive powder having a mean grain size of 0.001 to 1 um and a volume resistance of 10 0 to 10 8 Ω-cm and being at least one member selected from the group consisting of SnO 2 , In 2 O 3 , ZnO, BaTiO 3 , and SrTiO 3 which have electrically conductivity, a white inorganic powder having a particle size range of 0.01 to 5 um and a binder and the leader tape has a percent photo-transmission of at least 20%.
Claim 13
Dependent Claim
26 words
The magnetic tape having a leader tape as claimed in claim 10, wherein the white inorganic powder has a grain size of 0.01 to 3 μm.
Claim 14
Dependent Claim
43 words
The magnetic tape having a leader tape as claimed in claim 10, wherein the white inorganic powder is at least one member selected from the group consisting of alumina, titanium oxide, zinc sulfide, lithopone, barium sulfate, zinc oxide, aluminum silicate and silicon oxide.
Claim 15
Dependent Claim
39 words
The magnetic tape having a leader tape as claimed in claim 10, wherein the white inorganic powder is used in a proportion of up to 950 parts by weight to 100 parts by weight of the electrically conductive powder.
Claim 16
Dependent Claim
124 words
A magnetic tape having a leader tape comprising a coating layer provided on one or both sides of a support, at least one end of the tape, characterized in that the coating layer contains, as predominant components, an electrically conductive powder having a mean grain size of 0.001 to 1 um and a volume resistance of 10 0 to 10 8 Ω-cm and being at least one member selected from the group consisting of SnO 2 , In 2 O 3 , ZnO, BaTiO 3 , and SrTiO 3 which have electrically conductivity, a white resin powder having a particle size in the range of 0.1 to 10 um and a binder and the leader tape has a percent photo-transmission of at least 20%.
Claim 17
Dependent Claim
124 words
A magnetic tape having a leader tape comprising a coating layer provided on one or both sides of a support, at least one end of the tape, characterized in that the coating layer contains, as predominant components, an electrically conductive powder having a mean grain size of 0.001 to 1 um and a volume resistance of 10 0 to 10 8 Ω-cm and being at least one member selected from the group consisting of SnO 2 , In 2 O 3 , ZnO, BaTiO 3 , and SrTiO 3 which have electrically conductivity, a white resin powder having a particle size in the range of 0.1 to 10 um and a binder and the leader tape has a percent photo-transmission of at least 20%.
Claim 18
Dependent Claim
26 words
The magnetic tape having a leader tape as claimed in claim 14, wherein the white resin powder has a grain size of 0.1 to 3 μm.
Claim 19
Dependent Claim
51 words
The magnetic tape having a leader tape as claimed in claim 14, wherein the white resin powder is at least one member selected from the group consisting of acetylcellulose, polyethylene, polypropylene, polyester resin, polyamide resin, polyacrylonitrile resin, polyacetyl resin, phenol resin, urea resin, triazine resin, malamine resin and epoxy resin powders.
Claim 20
Dependent Claim
39 words
The magnetic tape having a leader tape as claimed in claim 14, wherein the white resin powder is used in a proportion of up to 450 parts by weight to 100 parts by weight of the electrically conductive powder.
Claim 21
Dependent Claim
88 words
A magnetic tape having a leader tape comprising a coating layer provided on one or both sides of a support at at least one end of said magnetic tape, characterized in that the coating layer contains, as predominant components, at least one electrically modified conductive powder selected from the group consisting of SnO 2 , InO 3 , ZnO, BatiO 3 and SrTiO 3 , a white inorganic powder, a white resin powder and a binder and the leader tape has a percent photo-transmission of at least 20%.
Claim 22
Dependent Claim
88 words
A magnetic tape having a leader tape comprising a coating layer provided on one or both sides of a support at at least one end of said magnetic tape, characterized in that the coating layer contains, as predominant components, at least one electrically modified conductive powder selected from the group consisting of SnO 2 , InO 3 , ZnO, BatiO 3 and SrTiO 3 , a white inorganic powder, a white resin powder and a binder and the leader tape has a percent photo-transmission of at least 20%.
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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) | 1990-07-13 | 1991-01-12 | 1991-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-13 | 1995-01-12 | 1995-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-13 | 1999-01-12 | 1999-07-14 | $7700.00 | Window Closed / Lapsed |