US4092256A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic coating compositions
Assignee: Individual
•
Filing: 1976-12-22
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Granted: 1978-05-30
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Expires: 1996-12-22
Abstract
Abstract A coating composition for use in the preparation of magnetic recording media is described. The composition contains finely divided magnetic particles dispersed in an organic solvent, containing in solution a hydroxyl group containing polymer having an OH number between about 100-500, a polyether urethane elastomer, an aliphatic polyisocyanate and a copper containing chelate catalyst, the organic portion of said chelate being of the general chemical structure ##STR1## wherein R and R' can be the same or different and represent alkyl groups containing 1-18 carbon atoms and aromatic groups, both substituted and unsubstituted.
Inventors
- 👤 Keith S. Goodson
- 👤 Duncan W. Frew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:09
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7028
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
111 words
A coating composition for use in the preparation of magnetic tapes comprising finely divided magnetic particles dispersed in an organic solvent containing in solution 2 to 10% by weight of a polyether urethane elastomer resin; 0.5 to 5% by weight of a hydroxy group containing polymer having an OH number between about 100-500; 0.01% to 0.06% by weight of a copper containing chelate catalyst, the organic portion of said chelate being of the general formula ##STR6## wherein R and R' can be the same or different and represents alkyl groups containing 1-18 carbon atoms and aromatic groups, both substituted and unsubstituted; and 0.2 to 0.8% by weight of an aliphatic polyisocyanate.
Claim 2
Dependent Claim
111 words
A coating composition for use in the preparation of magnetic tapes comprising finely divided magnetic particles dispersed in an organic solvent containing in solution 2 to 10% by weight of a polyether urethane elastomer resin; 0.5 to 5% by weight of a hydroxy group containing polymer having an OH number between about 100-500; 0.01% to 0.06% by weight of a copper containing chelate catalyst, the organic portion of said chelate being of the general formula ##STR6## wherein R and R' can be the same or different and represents alkyl groups containing 1-18 carbon atoms and aromatic groups, both substituted and unsubstituted; and 0.2 to 0.8% by weight of an aliphatic polyisocyanate.
Claim 3
Dependent Claim
47 words
The coating composition of claim 1 wherein said composition further comprises from about 3 to 20 mols of a diketone having the formula R--CO--CH 2 --CO--R', wherein R and R' are the same or different and are saturated aliphatic groups, per mol of the copper chelate catalyst.
Claim 4
Dependent Claim
13 words
The coating composition as defined in claim 2 wherein said diketone is 2,4-pentanedione.
Claim 5
Dependent Claim
33 words
The coating composition as defined in claim 1 wherein said hydroxyl group containing polymer is a phenoxy resin having the formula ##STR7## wherein n is in the range of about 80 to 120.
Claim 6
Dependent Claim
19 words
The coating composition as defined in claim 1 wherein said hydroxyl group containing polymer is a vinylacetatevinyl butyral copolymer.
Claim 7
Dependent Claim
15 words
The coating composition of claim 1 wherein the aliphatic polyisocyanate has the following formula ##STR8##
Claim 8
Dependent Claim
14 words
The coating composition of claim 1 wherein said copper chelate catalyst is copper acetylacetonate.
Claim 9
Dependent Claim
14 words
The coating composition of claim 1 wherein said copper chelate catalyst is copper benzoylacetonate.
Claim 10
Dependent Claim
36 words
The coating composition of claim 1 wherein the ratio of OH groups contained in the hydroxy group containing polymer to the NCO groups contained in the aliphatic polyisocyanate is in the range of 3.5 to 5.
Claim 11
Dependent Claim
31 words
The coating composition of claim 9 wherein the hydroxy group containing polymer is a phenoxy resin having the formula ##STR9## wherein n is in the range of about 80 to 120.
Claim 12
Dependent Claim
29 words
The coating composition of claim 2 wherein the diketone is present in an amount between about 0.05 and 0.25% by weight based upon the weight of the total composition.
Claim 13
Dependent Claim
31 words
The composition defined in claim 2 wherein the finely divided magnetic particles are present in an amount between 10 and 25% by weight based upon the weight of the total composition.
References Cited (Backward Citations)
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Cited
US3929658A
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JPS504123A
Cited
US3926826A
Cited
US4025694A
Cited
US4020236A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-05-29 | 1981-11-28 | 1982-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-29 | 1985-11-28 | 1986-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-29 | 1989-11-28 | 1990-05-30 | $7700.00 | Window Closed / Lapsed |