公开(公告)号：JPH05189746A

公开(公告)日：1993-07-30

申请号：JP521292

申请日：1992-01-14

Applicant: KAO CORP

Inventor： YANAI HIDETOSHI ,  UEDA YUKIHIRO

IPC: G11B5/73 ,  G11B5/735

Abstract: PURPOSE:To improve running characteristics and recording/reproducing characteristics by forming a magnetic layer on one side of a nonmagnetic substrate and a layer contg. an electric conductive polymer having pi-conjugated structure and a metallic salt of fatty acid on the other side. CONSTITUTION:A magnetic layer contg. required magnetic powder is formed on one side of a nonmagnetic substrate and a back coat layer contg. an electric conductive polymer having pi-conjugated structure and a metallic salt of fatty acid is formed on the other side to obtain a magnetic recording medium. The fatty acid is preferably 12-18C higher fatty acid. By the back coat layer, electrification is prevented, the surface roughness is controlled to a proper value and running characteristics and recording/reproducing characteristics are improved.

公开(公告)号：JPH03288325A

公开(公告)日：1991-12-18

申请号：JP9120690

申请日：1990-04-04

Applicant: KAO CORP

Inventor： YANAI HIDETOSHI

IPC: C09D175/04 ,  G11B5/73 ,  G11B5/735

Abstract: PURPOSE:To obviate the generation of the irregular winding of a tape in spite of repetitive traveling and to prevent the transfer of a back coat layer to a magnetic layer by allowing oleic acid and two kinds of carbon blacks having specific grain sizes in the back coat layer. CONSTITUTION:The back coat layer of the magnetic recording medium contains (a) the carbon black of 15 to 30nm average grain size, (b) the carbon black of 60 to 100nm average grain size and (c) the oleic acid. The back coat layer is so formed that the total content of the carbon black (a) and carbon black (b) in the back coat layer is 30 to 70wt.%, the weight ratio of (a)/(b) is 60/40 to 99/1 and the content of the oleic acid (c) is 1 to 10wt.% with respect to the total content of the carbon black (a) and the carbon black (b).

公开(公告)号：JPH04265515A

公开(公告)日：1992-09-21

申请号：JP2720491

申请日：1991-02-21

Applicant: KAO CORP

Inventor： ABE CHIAKI ,  KUDO MASUO ,  YANAI HIDETOSHI

IPC: G11B5/71 ,  C09D5/23 ,  C10M105/54 ,  C10N40/18 ,  G11B5/73

Abstract: PURPOSE:To prevent increase in the surface energy of a coating film when a lubricant bleeds out to the surface of a magnetic coating film, and to stabilize traveling property. CONSTITUTION:Fatty acid ester (A) expressed by general formula R-COO-Rf (wherein R is an alkyl group of 9-19 carbon number, Rf is a fluorinated alkyl group of 3-22 carbon number) and fatty acid (B) of 12-24 carbon number are used as the lubricant component of the magnetic layer.

公开(公告)号：JPH04192115A

公开(公告)日：1992-07-10

申请号：JP32669790

申请日：1990-11-27

Applicant: KAO CORP

Inventor： NAKANISHI KUNIYUKI ,  YANAI HIDETOSHI ,  HOSOYA MANABU ,  SHIRASAKI KEIJI

IPC: G11B5/702 ,  C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/00 ,  C09D175/04 ,  G11B5/708 ,  G11B5/71 ,  G11B5/712

Abstract: PURPOSE:To maintain high durability of the medium even when the environment changes by incorporating specified phosphate, silane coupling agent and mixture of higher fatty acid and higher fatty acid ester. CONSTITUTION:The magnetic layer contains the following components. Namely, a phosphate expressed by formula I, wherein R1 is an aliphatic hydrocarbon group of 1 - 24 carbon number, A is an alkylene group of 2 - 4 carbon number, n is 0 or an integer from 1 to 30, and m is 1, 1.5 or 2. A silane coupling agent expressed by formula II, wherein R2 is an alkyl group of 1 - 4 carbon number and R3 is an aliphatic hydrocarbon group of 1 - 24 carbon number. And a mixture of higher fatty acid (A) having 12 - 22 carbon number and higher fatty acid ester (B) of 12 - 22 carbon number compounded by the weight ratio range of A:B from 50:50 to 90:10.

公开(公告)号：JPH02199624A

公开(公告)日：1990-08-08

申请号：JP1814189

申请日：1989-01-27

Applicant: KAO CORP

Inventor： KANNEN NAOKI ,  YAMASHITA KAZUTAKA ,  YANAI HIDETOSHI

IPC: G11B5/708 ,  C09D5/23 ,  C09D101/18 ,  C09D127/00 ,  C09D127/04 ,  C09D127/06 ,  C09D175/04 ,  G11B5/702 ,  G11B5/71

Abstract: PURPOSE:To obtain such a medium with excellent durability and little abrasion of the magnetic layer by incorporating a specific ester compd. and a copolymer of vinyl chloride and a compd. having -COOH as a polar group into the magnetic layer. CONSTITUTION:The ester compd. expressed by formula I and the copolymer of vinyl chloride and the compd. having a polar group of -COOH or nitrocellulose having the same polar group are incorporated into the magnetic layer essentially comprising magnetic powder and a binder. In formula I, R represents an aliphatic hydrocarbon group with a branched chain with 3 - 10 carbon and R' represents a satd. or unsatd. aliphatic hydrocarbon group with 7 - 21 carbons. This gives more preferable lubricating property and the obtd. medium has significantly improved durability in a wide range of environments.

公开(公告)号：JPH02199623A

公开(公告)日：1990-08-08

申请号：JP1814089

申请日：1989-01-27

Applicant: KAO CORP

Inventor： KANNEN NAOKI ,  YAMASHITA KAZUTAKA ,  YANAI HIDETOSHI

IPC: G11B5/708 ,  C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/00 ,  C09D175/06

Abstract: PURPOSE:To obtain such a medium with excellent durability and little abrasion of the magnetic layer by incorporating a specific phosphate copd., magnetic powder subjected to a surface treatment with org. silane compd. having hydolytic alkoxysilane group, and a specific ester compd. into the magnetic layer. CONSTITUTION:The magnetic layer contains the phosphate compd. expressed by formula I, the magnetic powder subjected to the surface treatment with org. silane compd. having hydrolytic alkoxysilane group in one molecule, and the ester compd. expressed by formula II. In formula I, R1 represents a hydrocarbon group with 2 - 28 carbons, A is an alkylene group with 2 - 4 carbons, (n) is 0 or an integer from 1 to 30. In formula II, R represents an aliphatic hydrocarbon group with a branched chain with 3 - 10 carbons and R' represents a satd. aliphatic hydrocarbon group with 7 - 21 carbons. This gives more preferable lubricating property and the obtd. medium has significantly improved durability in a wide range of environments.

公开(公告)号：JPH05159273A

公开(公告)日：1993-06-25

申请号：JP32564191

申请日：1991-12-10

Applicant: KAO CORP

Inventor： YANAI HIDETOSHI ,  UEDA YUKIHIRO

IPC: G11B5/70 ,  G11B5/71 ,  G11B5/735

Abstract: PURPOSE:To provide the magnetic recording medium having excellent traveling stability. CONSTITUTION:The magnetic recording medium is constituted by providing a magnetic layer on one surface side of a nonmagnetic base and providing a resin coating film layer contg. carbon black on the other surface side. The carbon black of the resin coating film layer has characteristic of about 300 to 500ml/100g oil absorption. Further, higher fatty acid and/or fatty acid ester having about

公开(公告)号：JPH0393032A

公开(公告)日：1991-04-18

申请号：JP22907789

申请日：1989-09-04

Applicant: KAO CORP

Inventor： YANAI HIDETOSHI ,  ISHIKAWA AKIRA

IPC: C09D5/23 ,  C09C1/48 ,  C09D7/12 ,  C09D101/18 ,  C09D175/00 ,  C09D175/04 ,  G11B5/73 ,  G11B5/735

Abstract: PURPOSE:To improve traveling durability of a magnetic recording medium to be used in a belt-driven cartridge by incorporating carbon black having a specified average particle size, titanium oxide, and a binder comprising nitrocellulose and polyurethane resin with a specified weight ratio into the back coating layer of the medium. CONSTITUTION:Carbon black (a) having the average particle size of 20 - 100nm, titanium oxide (b) having the average particle size of 100 - 600nm, and a binder (c) comprising at least two compds. of nitrocellulose and polyurethane resin are incorporated into the back coating layer of the recording medium which is used in a belt-driven cartridge. The weight ratio of (a) to (b) is specified to 99:1 - 60:40, the weight ratio of (c) to (a+b) is to 70:30 - 20:80, and the weight ratio of gun cotton to polyurethane in (c) is 10:90 - 90:10. By this method, traveling durability of the medium can be improved.

公开(公告)号：JPH02199622A

公开(公告)日：1990-08-08

申请号：JP1813989

申请日：1989-01-27

Applicant: KAO CORP

Inventor： KANNEN NAOKI ,  YAMASHITA KAZUTAKA ,  YANAI HIDETOSHI

IPC: G11B5/708 ,  C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/00 ,  C09D175/04 ,  C10M105/36 ,  C10N40/18

Abstract: PURPOSE:To obtain such a medium with excellent durability and little abrasion of the magnetic layer by incorporating a specific ester compd. into the magnetic layer. CONSTITUTION:The ester compd. expressed by formula I is incorporated into the magnetic layer essentially comprising magnetic powder and a binder. In formula I, R represents an aliphatic hydrocarbon group with a branched chain with 3 - 10 carbons and R' represents a satd. or unsatd. aliphatic hydrocarbon group with 7 - 21 carbons. This ester compd. is produced from a branched alcohol with 3 - 10 carbons and a monobasic fatty acid with 8 - 22 carbons, and more preferably a onobasic fatty acid with 12 - 18 carbons. This gives more preferable lubricating property and the obtd. medium has significantly improved durability in a wide range of environments.