US4048375A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording media of improved mechanical resistance
Assignee: BASF SE
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Filing: 1976-07-26
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Granted: 1977-09-13
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Expires: 1996-07-26
Abstract
Abstract Magnetic recording media consisting of a non-magnetic base and, applied thereto, a firmly adhering magnetic coating based on finely divided magnetic pigment dispersed in organic binders, which coating contains, according to the invention, salts of long-chain basic polyaminoamides with high molecular weight organic acid esters. Such magnetic recording media exhibit improved mechanical resistance and improved adhesion of the coating to the base, coupled with advantageous electromagnetic properties.
Inventors
- 👤 Gustav Loewenberg
- 👤 Hans-Joerg Hartmann
- 👤 Dieter Schaefer
- 👤 Herbert Motz
- 👤 Helmut Jakusch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:46
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7028; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31725; Y10T428/31736; Y10T428/31765
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
139 words
In a magnetic recording medium comprising a non-magnetizable base and, applied thereto, a firm adhering coating suitable for magnetic recording and consisting essentially of a finely divided magnetic powder dispersed in an organic polymeric binder, the improvement which comprises: including in said coating from 0.2 to 5% by weight, based on the total weight of the coating, of a neutral salt of (a) a basic polyaminoamide, obtained by condensing dimerized and trimerized unsaturated fatty acids with aliphatic polyamines possessing two primary amino groups and having an amine value of from 100 to 500 and (b) an organic acid ester, obtained by reacting equimolar amounts of a polyalkylene glycol of molecular weight from 100 to 500, a monocarboxylic acid of 10 to 22 carbon atoms and a dicarboxylic acid anhydride or a dicarboxylic acid of 2 to 8 carbon atoms.
Claim 2
Dependent Claim
139 words
In a magnetic recording medium comprising a non-magnetizable base and, applied thereto, a firm adhering coating suitable for magnetic recording and consisting essentially of a finely divided magnetic powder dispersed in an organic polymeric binder, the improvement which comprises: including in said coating from 0.2 to 5% by weight, based on the total weight of the coating, of a neutral salt of (a) a basic polyaminoamide, obtained by condensing dimerized and trimerized unsaturated fatty acids with aliphatic polyamines possessing two primary amino groups and having an amine value of from 100 to 500 and (b) an organic acid ester, obtained by reacting equimolar amounts of a polyalkylene glycol of molecular weight from 100 to 500, a monocarboxylic acid of 10 to 22 carbon atoms and a dicarboxylic acid anhydride or a dicarboxylic acid of 2 to 8 carbon atoms.
Claim 3
Dependent Claim
32 words
A magnetic recording medium as set forth in claim 1 wherein the amount of said neutral salt is from 0.5 to 3% by weight based on the total weight of the coating.
Claim 4
Dependent Claim
65 words
A magnetic recording medium as set forth in claim 1, wherein the organic acid ester (b) is obtained by reacting equimolar amounts of a polyalkylene glycol selected from the group consisting of polyethylene glycol and polypropylene glycol having a molecular weight of from 150 to 500, a fatty acid of 10 to 18 carbon atoms and a dicarboxylic acid of 2 to 8 carbon atoms.
Claim 5
Dependent Claim
31 words
A magnetic recording medium as set forth in claim 1 wherein said aliphatic polyamine is selected from the group consisting of diethylenetriamine, triethylenetetramine, tetramethylenepentamine, 1,4-diaminobutane, 1,3-diaminobutane, hexanemethylenediamine, diacetoneamine, 3-(N-isopropylamino)-propylamine and 3,3'-imino-bis-propylamine.
References Cited (Backward Citations)
US3387993A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-12 | 1981-03-14 | 1981-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-12 | 1985-03-14 | 1985-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-12 | 1989-03-14 | 1989-09-13 | $7700.00 | Window Closed / Lapsed |