公开(公告)号：JPH0490123A

公开(公告)日：1992-03-24

申请号：JP20639590

申请日：1990-08-02

Applicant: KAO CORP

Inventor： SANO YUTAKA ,  KUDO MASUO ,  KONDO KIICHIRO ,  HASHIMOTO SHINGO

IPC: G11B5/702 ,  C09D5/23 ,  C09D175/00 ,  C09D175/04 ,  G11B5/712

Abstract: PURPOSE:To improve the durability of a magnetic layer by incorporating magnetic powders covered with a specified reaction product and a specified binder into the magnetic layer. CONSTITUTION:The magnetic layer consists of magnetic powders and a binder. The magnetic powder is covered with the reaction product of amino group-contg. silane coupling agent and one or two more kinds of compds. selected from acid anhydride having 6 - 22C and alkylketene dimers. As for the binder, polyurethane resin incorporating a metallic sulfonate group is used. The concn. of the metal sulfonate group is specified to 0.1 - 100eq./10 g. Further, polyurethane resin of 7,000 - 70,000mol.wt. and nitrocellulose are also used. Thereby, wear of the magnetic layer is decreased, which improves the durability.

公开(公告)号：JPH05174364A

公开(公告)日：1993-07-13

申请号：JP33897391

申请日：1991-12-20

Applicant: KAO CORP

Inventor： KUDO MASUO ,  UEDA YUKIHIRO

IPC: G11B5/708 ,  C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/00 ,  C09D175/04 ,  G11B5/73

Abstract: PURPOSE:To provide a magnetic recording medium in which a magnetic layer is hard to be worn and is superior in the durability by incorporating a specific quantity of carbon black which is treated with a metallic salt of fatty acid in the magnetic layer. CONSTITUTION:For this purpose, the carbon black with 300-500ml oil absorption/100g is used. 2-12 pts.wt. of Na salts of lauric acid are used for 100 pts.wt. of fine gamma-Fe2O3 powder and the carbon black is stirred under-heating in toluene. The carbon black in which the Na salt of lauric acid is impregnated, is mixed and dispersed with a binder resin, an organic solvent, and other required component, and a magnetic coating material is prepared and it is applied and dried and the magnetic recording medium is formed.

公开(公告)号：JPH04368619A

公开(公告)日：1992-12-21

申请号：JP14441091

申请日：1991-06-17

Applicant: KAO CORP

Inventor： KUDO MASUO ,  TAKADA HIROSHI

IPC: G11B5/708 ,  C09D5/23 ,  C09D101/18 ,  C09D175/00 ,  C09D175/04 ,  C10M105/74 ,  C10N40/18 ,  G11B5/71 ,  G11B5/73

Abstract: PURPOSE:To drastically improve durability by increasing lubricity by using phosphoric ester specified in formulae as a lubricant. CONSTITUTION:A phosphoric polyester shown in formula I or II is used as a lubricant for a magnetic recording medium whose lubricity is improved and durability is drastically improved is obtained. In formulae, (m) or (n) is 0 or integer of >=1, and m+n=15.

公开(公告)号：JPH04222919A

公开(公告)日：1992-08-12

申请号：JP40660890

申请日：1990-12-26

Applicant: KAO CORP

Inventor： KUDO MASUO ,  SANO YUTAKA ,  KONDO KIICHIRO ,  HASHIMOTO SHINGO ,  WAKANA SHIGEAKI

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

Abstract: PURPOSE:To form a magnetic recording medium excellent in durability by forming a magnetic later containing an amino group-contg. silane coupling agent, a compd. comprising anhydride of specified carbon number and alkylketene dimers, and a binder comprising polyurethane resin. CONSTITUTION:This magnetic recording medium consists of a magnetic layer formed on a nonmagnetic supporting body. This magnetic layer consists of an amino group-contg. silane coupling agent and a magnetic powder coated with a reaction product of acid anhydride having 6-22 carbon number and one or more kinds of alkylketene dimers. The magnetic layer also contains a binder comprising polyvinyl chloride containing hydroxyl group, epoxy group and metal sulfonate group in one molecule and polyurethane resin containing 0.1-100 equiv./10 g metal sulfonate group. Thereby, the obtd. magnetic recording medium has excellent durability.

公开(公告)号：JPH0490122A

公开(公告)日：1992-03-24

申请号：JP20639490

申请日：1990-08-02

Applicant: KAO CORP

Inventor： SANO YUTAKA ,  KUDO MASUO ,  KONDO KIICHIRO ,  HASHIMOTO SHINGO

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

Abstract: PURPOSE:To improve the durability of a magnetic layer by incorporating magnetic powders covered with a specified reaction product, polyvinyl chloride and polyurethane resin into the magnetic layer. CONSTITUTION:The magnetic layer consists of magnetic powders and a binder. The magnetic powder is covered with the reaction product of amino group-contg. silane coupling agent and one or two more kinds of compds. selected from the group consisting of acid anhydride of 6 - 22C and alkylketene dimers. As for the binder, polyvinyl chloride containing hydroxyl group, epoxy group and metal sulfonate group in one molecule and polyurethane resin of 7,000 - 70,000 mol.wt. is used. Thereby, wear of the magnetic layer is decreased, which improves the durability of the layer.

公开(公告)号：JPH052736A

公开(公告)日：1993-01-08

申请号：JP15324691

申请日：1991-06-25

Applicant: KAO CORP

Inventor： KUDO MASUO ,  TANAKA TOSHINORI ,  SUZUE SHIGETOSHI

IPC: G11B5/71 ,  C09D5/23 ,  C10M105/34 ,  C10N40/18 ,  G11B5/73

Abstract: PURPOSE:To impart good libricity to the above-mentioned medium and to greatly improve its durability by using an ester compd. having a specific structure as a lubricant. CONSTITUTION:The ester compd. expressed by formula I is incorporated into the magnetic layer of a nonmagnetic base. The ester compd. can be synthesized by dehydration esterification reaction from branched stearic acid and various kinds of 10 to 22C alcohols, such as n-decanol, n-hexadecanol and n-octadecanol. The ester compd. is used at 1 to 15 pts. wt., more preferably 3 to 10 pts. wt. in total per 100 pts. wt. magnetic powder. The ester compd. is previously incorporated into a magnetic coating material or a sol. of a general-purpose solvent, such as isopropaneol or hexane, is applied on a magnetic coated film after the formation of this film and is dried to impregnate the ester compd. into the film. The application of the ester compd. is allowed by the similar method even on the medium formed with the magnetic layer on the nonmagnetic base by a sputtering or vapor deposition method.

公开(公告)号：JPH052735A

公开(公告)日：1993-01-08

申请号：JP15324591

申请日：1991-06-25

Applicant: KAO CORP

Inventor： KUDO MASUO ,  TANAKA TOSHINORI ,  SUZUE SHIGETOSHI

IPC: G11B5/71 ,  C09D5/23 ,  C10M105/24 ,  C10N40/18 ,  G11B5/73

Abstract: PURPOSE:To impart good libricity to the above-mentioned medium and to great ly improve its durability by using a fatty acid having the branched chain expressed by specific formula as a lubricant. CONSTITUTION:The branched fatty acid expressed by the formula is incorporated into the magnetic layer on a nonmagnetic base. The branched fatty acid is produced by the addition reaction of olefin and fatty acid. As the olefin, 6 to 32C, more preferably 6 to 28C alpha-olefins are used. As the fatty acid, 6 to 26C caproic acid, caprilic acid, lauric acid, mysistic acid, malmitic acid, stearic acid, etc., are used as the fatty acid. The charging quantity of the olefin in the above-mentioned reaction is specified to 50 to 60mol% of the fatty acid. An org. peroxide as a radical generating agent, such as dialkyl peroxide or tertiary butyl perioxide, is used at the time of the addition reaction. The branched fatty acid is used at 1 to 15 pts. wt., more preferably 3 to 10 pts.wt. in total per 100 pts.wt. magnetic powder.

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：JPH05174363A

公开(公告)日：1993-07-13

申请号：JP33897291

申请日：1991-12-20

Applicant: KAO CORP

Inventor： KUDO MASUO ,  UEDA YUKIHIRO

IPC: G11B5/708 ,  C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/00 ,  C09D175/04 ,  C10M103/02 ,  C10N20/06 ,  C10N40/18 ,  G11B5/71 ,  G11B5/73

Abstract: PURPOSE:To provide a magnetic recording medium in which a magnetic layer is hard to be worn and is superior in the durability for environmental change. CONSTITUTION:In the magnetic recording medium in which the magnetic layer containing magnetic powder and a binder is provided on a substrate, the magnetic layer is characterized by incorporating the components described hereunder; (1), (2) and (3). (1) Carbon black with 25-130nm of the average single particle diameter and 300-550ml oil absorption/100g carbon black. (2) Carbon black with 300-1000nm of the average single particle diameter. (3) At least one kind selected from higher fatty acids and fatty acid esters having

公开(公告)号：JPH05174362A

公开(公告)日：1993-07-13

申请号：JP33897191

申请日：1991-12-20

Applicant: KAO CORP

Inventor： KUDO MASUO ,  UEDA YUKIHIRO

IPC: G11B5/708 ,  C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/00 ,  C09D175/04 ,  C10M103/02 ,  C10N40/18 ,  G11B5/73

Abstract: PURPOSE:To provide a magnetic recording medium having an excellent lubricity and durability by incorporating a metallic salt of fatty acid and carbon black having a specific average single particle diameter in a magnetic layer. CONSTITUTION:The metallic salts of 12-18C higher fatty acids such as Zn stearate, Ba stearate, Ca stearate, and Al, oleic acid are used 3-15 pts.wt. for 100 pts.wt. of magnetic powder. Also the average single particle diameter of the carbon black is 0.2-1.0mum, and is preferably in a range of 3-1.0mum and the carbon black is used 3-15 pts.wt. for 100 pts.wt. of the magnetic powder. The magnetic powder is an acicular fine gamma-Fe2O3, or a Co doped gamma-Fe2O3, etc., and as the binder polyurethane and polyvinyl chloride, etc., are used and 15-60 pts.wt. of it are used for 100 pts.wt. of the magnetic powder. The mixture is applied on e.g. a substrate of polyethylene terephthalate.