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US4675250A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic recording medium

Assignee: Fujifilm Holdings Corp
•
Filing: 1986-03-11
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Granted: 1987-06-23
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Expires: 2006-03-11
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Abstract

Abstract A magnetic recording medium having improved lubricity and durability properties which comprises a magnetic powder, a resin binder and an ester compound of the formula (1): <IMAGE> (1) in which R1 and R2 are each a straight or branched, saturated alkyl having 1 to 25 carbon atoms and R3 is an unsaturated hydrocarbon group or a straight or branched, saturated alkyl and has 7 to 27 carbon atoms, provided that the total carbon atom number of R1 and R2 ranges from 18 to 32 when R3 is the unsaturated hydrocarbon group and that ranges from 22 to 32 when R3 is the saturated alkyl. It is improved in lubricity and durability.

Inventors

  • 👤 Hiroyuki Kanai
  • 👤 Tetsuya Imamura
  • 👤 Takeshi Takeuchi
  • 👤 Shigetoshi Suzue

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 09:35
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/71; 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: 13
Claim 1
Independent Claim 97 words
A magnetic recording medium which comprises a magnetic powder, a resin binder and an ester lubricant of the formula (1): ##STR3## in which R1 and R2 are each a straight or branched, saturated alkyl having 1 to 25 carbon atoms and R3 is an unsaturated hydrocarbon group or a straight or branched, saturated alkyl and has 7 to 27 carbon atoms, provided that the total carbon atom number of R1 and R2 ranges from 18 to 32 when R3 is the unsaturated hydrocarbon group and that ranges from 22 to 32 when R3 is the saturated alkyl.
Claim 2
Dependent Claim 97 words
A magnetic recording medium which comprises a magnetic powder, a resin binder and an ester lubricant of the formula (1): ##STR3## in which R1 and R2 are each a straight or branched, saturated alkyl having 1 to 25 carbon atoms and R3 is an unsaturated hydrocarbon group or a straight or branched, saturated alkyl and has 7 to 27 carbon atoms, provided that the total carbon atom number of R1 and R2 ranges from 18 to 32 when R3 is the unsaturated hydrocarbon group and that ranges from 22 to 32 when R3 is the saturated alkyl.
Claim 3
Dependent Claim 36 words
A magnetic recording medium according to claim 1, in which the total carbon atoms of R1 and R2 ranges from 18 to 26 and R3 is an unsaturated hydrocarbon group having 15 to 27 carbon atoms.
Claim 4
Dependent Claim 32 words
A magnetic recording medium according to claim 1, in which the total carbon atoms of R1 and R2 ranges from 22 to 26 and R3 is a straight or branched, saturated alkyl.
Claim 5
Dependent Claim 68 words
A magnetic recording medium according to claim 1, wherein said magnetic powder is present in an amount of 100 parts by weight, said resin binder is present in an amount of 15 to 60 parts by weight based on 100 parts by weight of the magnetic powder and said ester lubricant is present in an amount of 1 to 15 percent by weight based on the magnetic powder.
Claim 6
Dependent Claim 30 words
A magnetic recording medium according to claim 1, which comprises a substrate, which has been coated with a composition comprising said magnetic powder, said resin binder and said ester lubricant.
Claim 7
Dependent Claim 53 words
A magnetic recording medium according to claim 1, wherein the ester lubricant is derived from an unsaturated fatty acid and an alcohol, said unsaturated fatty acid selected from the group consisting of decylenic acid, undecylenic acid, physeteric acid, palmitoleic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, erucic acid and nervonic acid.
Claim 8
Dependent Claim 55 words
A magnetic recording medium according to claim 1, wherein the resin binder is selected from the group consisting of polyurethane, polyester, polyvinyl chloride, vinyl chloride/vinyl acetate copolymer, polyacrylonitrile, nitrile rubber, epoxy resin, alkyd resin, polyamide, polyacrylate, polymethacrylate, polyvinyl acetate, polyvinyl butyral, polyvinylidene chloride, vinylidene chloride copolymer, nitrocellulose, maleic acid-modified vinyl chloride/vinyl acetate copolymer and ethylcellulose.
Claim 9
Dependent Claim 17 words
A magnetic recording medium according to claim 1, which further comprises a plasticizer or a hardening agent.
Claim 10
Dependent Claim 22 words
A magnetic recording medium according to claim 1, wherein the magnetic powder comprises an acicular metal oxide or a metallic iron powder.
Claim 11
Dependent Claim 41 words
A magnetic recording medium according to claim 9, wherein the metallic iron powder is surface treated or further mixed with a small amount of nickel, cobalt, titanium, silicon or aluminum in the form of an element, a salt or an oxide.
Claim 12
Dependent Claim 18 words
A magnetic recording medium according to claim 1, which comprises an additional lubricant other than said ester lubricant.
Claim 13
Dependent Claim 42 words
A magnetic recording medium according to claim 1, wherein the ester lubricant is selected from the group consisting of 2,6-decyltridecyl oleate, 2-octyldodecyl oleate, 2-octyldodecyl erucate, 2-decyltridecyl linoleate, 2-decyltetradecyl oleate, 2-tetradecyloctadecyl oleate, 2-dodecyltetradecyl erucate, 2-decyltetradecyl linoleate, 2-tetradecyloctadecyl undecylenate, 2-decylhexadecyl undecylenate and 2-octyldodecyl nervonate.

References Cited (Backward Citations)

US4172176A Cited
US4247407A Cited
US4383001A Cited
US4383000A Cited
US4420540A Cited
US4522885A Cited
US4595640A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-06-22 1990-12-22 1991-06-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-06-22 1994-12-22 1995-06-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-06-22 1998-12-22 1999-06-23 $7700.00 Window Closed / Lapsed

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