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US4567109A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic recording media

Assignee: Emtec Magnetics GmbH
•
Filing: 1983-07-20
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Granted: 1986-01-28
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Expires: 2003-07-20
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Abstract

Abstract Magnetic recording media comprising a non-magnetic base which is provided with a magnetic layer which consists essentially of a dispersion of an anisotropic magnetic material in a mixture of an OH-containing polyurea-urethane binder, which is crosslinked with a polyisocyanate, with a physically drying binder.

Inventors

  • 👤 August Lehner
  • 👤 Milan Velic
  • 👤 Helmut Kopke
  • 👤 Werner Balz
  • 👤 Werner Lenz
  • 👤 Reinhold Baur
  • 👤 Milena Melzer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 00:59
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7021; C; C08; C08L; C08L75/00; C08L75/04; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551; Y10T428/31609; Y10T428/31855; Y10T428/31935; Y10T428/31942; Y10T428/31971

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 89 words
A magnetic recording medium which comprises a magnetic layer which is applied to a non-magnetic base and consists essentially of a dispersion of an anisotropic magnetic material in a mixture of an OH-containing polyurethane compound, which has been finally crosslinked with a polyisocyanate, and a physical drying binder, wherein the binder mixture consists essentially of Component 1, which is a low molecular weight OH-containing polyurea-urethane which has an OH number of from 30 to 160 and an average number molecular weight of 1,500 to 40,000 and is obtained from
Claim 2
Dependent Claim 89 words
A magnetic recording medium which comprises a magnetic layer which is applied to a non-magnetic base and consists essentially of a dispersion of an anisotropic magnetic material in a mixture of an OH-containing polyurethane compound, which has been finally crosslinked with a polyisocyanate, and a physical drying binder, wherein the binder mixture consists essentially of Component 1, which is a low molecular weight OH-containing polyurea-urethane which has an OH number of from 30 to 160 and an average number molecular weight of 1,500 to 40,000 and is obtained from
Claim 3
Dependent Claim 145 words
IA 1 mole of a polydiol having a molecular weight of from 400 to 4,000, 1.IB from 0.2 to 10 moles of a diol of 2 to 18 carbon atoms, 1.IC from 0.1 to 4 moles of a primary or secondary aminoalcohol of 2 to 20 carbon atoms, and 1.II from 1.20 to 13 moles of a diisocyanate of 6 to 30 carbon atoms, the proportion of NCO groups in the diisocyanate being from 65 to 95%, based on Components 1.IA to 1.IC, of the equivalent amount of OH and NH groups, with the proviso that the non-pigmented crosslinked film has a tensile strength greater than 15 N/mm 2 , an elongation at break greater than 50%, a modulus of elasticity greater than 150 N/mm 2 and a pendulum hardness of from 30 to 140 sec, and Component 2, which is a physically drying binder.
Claim 4
Dependent Claim 145 words
IA 1 mole of a polydiol having a molecular weight of from 400 to 4,000, 1.IB from 0.2 to 10 moles of a diol of 2 to 18 carbon atoms, 1.IC from 0.1 to 4 moles of a primary or secondary aminoalcohol of 2 to 20 carbon atoms, and 1.II from 1.20 to 13 moles of a diisocyanate of 6 to 30 carbon atoms, the proportion of NCO groups in the diisocyanate being from 65 to 95%, based on Components 1.IA to 1.IC, of the equivalent amount of OH and NH groups, with the proviso that the non-pigmented crosslinked film has a tensile strength greater than 15 N/mm 2 , an elongation at break greater than 50%, a modulus of elasticity greater than 150 N/mm 2 and a pendulum hardness of from 30 to 140 sec, and Component 2, which is a physically drying binder.
Claim 5
Dependent Claim 88 words
A magnetic recording medium which comprises a magnetic layer which is applied to a non-magnetic base and consists of a dispersion of an anisotropic magnetic material in a mixture of an OH-containing polyurethane compound, which has been finally crosslinked with a polyisocyanate, and a physical drying binder, wherein the binder mixture consists essentially of Component 1, which is a low molecular weight OH-containing polyurea-urethane which has an OH number of from 30 to 160 and an average number molecular weight of 1,500 to 40,000 and is obtained from
Claim 6
Dependent Claim 88 words
A magnetic recording medium which comprises a magnetic layer which is applied to a non-magnetic base and consists of a dispersion of an anisotropic magnetic material in a mixture of an OH-containing polyurethane compound, which has been finally crosslinked with a polyisocyanate, and a physical drying binder, wherein the binder mixture consists essentially of Component 1, which is a low molecular weight OH-containing polyurea-urethane which has an OH number of from 30 to 160 and an average number molecular weight of 1,500 to 40,000 and is obtained from
Claim 7
Dependent Claim 160 words
IA 1 mole of a polydiol having a molecular weight of from 400 to 4,000, 1.IB from 0.2 to 9 moles of a diol of 2 to 18 carbon atoms, 1.IC from 0.1 to 4 moles of a primary or secondary aminoalcohol of 2 to 20 carbon atoms, 1.ID from 0.01 to 1 mole of a triol of 3 to 18 carbon atoms, and 1.II from 1.25 to 13 moles of a diisocyanate of 6 to 30 carbon atoms, the proportion of NCO groups in the diisocyanate being from 65 to 95%, based on Components 1.IA to 1.ID, of the equivalent amount of OH and NH groups, with the proviso that the non-pigmented crosslinked film has a tensile strength greater than 15 N/mm 2 , an elongation at break greater than 50%, a modulus of elasticity greater than 150 N/mm 2 and a pendulum hardness of from 30 to 140 sec, and Component 2, which is a physically drying binder.
Claim 8
Dependent Claim 160 words
IA 1 mole of a polydiol having a molecular weight of from 400 to 4,000, 1.IB from 0.2 to 9 moles of a diol of 2 to 18 carbon atoms, 1.IC from 0.1 to 4 moles of a primary or secondary aminoalcohol of 2 to 20 carbon atoms, 1.ID from 0.01 to 1 mole of a triol of 3 to 18 carbon atoms, and 1.II from 1.25 to 13 moles of a diisocyanate of 6 to 30 carbon atoms, the proportion of NCO groups in the diisocyanate being from 65 to 95%, based on Components 1.IA to 1.ID, of the equivalent amount of OH and NH groups, with the proviso that the non-pigmented crosslinked film has a tensile strength greater than 15 N/mm 2 , an elongation at break greater than 50%, a modulus of elasticity greater than 150 N/mm 2 and a pendulum hardness of from 30 to 140 sec, and Component 2, which is a physically drying binder.
Claim 9
Dependent Claim 158 words
A magnetic recording medium as defined in claim 1, wherein Component 2 consists essentially of a high molecular weight thermoplastic linear polyurethane which is soluble in tetrahydrofuran and is obtained from 2.A 1 mole of a polyesterol having a molecular weight of from 400 to 4,000, 2.B from 0.3 to 15 moles of a straight-chain aliphatic diol of 2 to 10 carbon atoms, 2.C from 0 to 1.5 moles of a triol of 3 to 10 carbon atoms, and from 1.25 to 17 moles of a diisocyanate of 6 to 30 carbon atoms, the amount of NCO groups being about equivalent to the amount of OH groups in Components 2.A, 2.B and 2.C together, with the proviso that the non-pigmented film has a tensile strength of from 40 to 95 N/mm 2 and an elongation at break of from 100 to 1,400%, and in which the ratio of Component 1 to Component 2 is from 9:1 to 1:9.
Claim 10
Dependent Claim 109 words
A magnetic recording medium as defined in claim 1, wherein Component 2 consists essentially of a polyvinylformal binder containing not less than 65% of vinylformal groups, or of a copolymer of 50-95% by weight of vinyl chloride and 5-50% by weight of a monoester or diester of an aliphatic diol of 2 to 4 carbon atoms with acrylic acid or methacrylic acid, or of a phenoxy resin of the formula ##STR4## where n is about 100, or of a diester and/or triester of cellulose with one or more carboxylic acids of 1 to 4 carbon atoms, the ratio of Component 1 to Component 2 being from 1:0.8 to 1:0.1.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-01-27 1989-07-29 1990-01-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-01-27 1993-07-29 1994-01-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-01-27 1997-07-29 1998-01-28 $7700.00 Window Closed / Lapsed

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