Patent US1980886A successfully refreshed from Google Patents.
US4263188A
Expired / Lapsed
US
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Aqueous coating composition and method
Assignee: Verbatim Corp
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Filing: 1979-05-23
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Granted: 1981-04-21
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Expires: 1999-05-23
Abstract
Abstract An aqueous coating composition for forming a magnetic tape which has good adhesion for polyethylene terephthalate substrate. The composition is a stable dispersion in water of urethane with carboxylic acid groups in the backbone chain and includes a polyfunctional cross-linking agent.
Inventors
- 👤 George J. Hampton
- 👤 William F. Maida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:52
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7021; C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/0804; C08G18/0819; C08G18/0823
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
31 words
An aqueous coating composition for forming a magnetic recording layer, said coating composition comprising a stable aqueous dispersion of magnetic pigment and polyurethane with carboxylic acid groups in the backbone chain.
Claim 2
Dependent Claim
31 words
An aqueous coating composition for forming a magnetic recording layer, said coating composition comprising a stable aqueous dispersion of magnetic pigment and polyurethane with carboxylic acid groups in the backbone chain.
Claim 3
Dependent Claim
19 words
The coating composition of claim 1 in which said dispersion is at a pH level in excess of 7.5.
Claim 4
Dependent Claim
18 words
The coating composition of claim 1 in which said dispersion includes a pH adjusting agent comprising ammonium hydroxide.
Claim 5
Dependent Claim
18 words
The coating composition of claim 1 in which said dispersion includes a polyfunctional cross-linking agent for said polyurethane.
Claim 6
Dependent Claim
15 words
The coating composition of claim 4 in which said cross-linking agent comprises a polyfunctional aziridine.
Claim 7
Dependent Claim
12 words
The coating composition of claim 1 in which said polyurethane is aromatic.
Claim 8
Dependent Claim
12 words
The coating composition of claim 1 in which said polyurethane is aliphatic.
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) | 1984-04-20 | 1984-10-20 | 1985-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-20 | 1988-10-20 | 1989-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-20 | 1992-10-20 | 1993-04-21 | $7700.00 | Window Closed / Lapsed |