公开(公告)号：US5176955A

公开(公告)日：1993-01-05

申请号：US687133

申请日：1991-04-18

申请人： Kiyomi Ejiri ,  Hiroaki Araki ,  Hiroshi Hashimoto

发明人： Kiyomi Ejiri ,  Hiroaki Araki ,  Hiroshi Hashimoto

IPC分类号： C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/00 ,  C09D175/04 ,  G11B5/70 ,  G11B5/702 ,  G11B5/706 ,  G11B5/708 ,  G11B5/84 ,  G11B5/842

CPC分类号： G11B5/7013 ,  G11B5/7023 ,  G11B5/706 ,  Y10S428/90 ,  Y10T428/265 ,  Y10T428/3158 ,  Y10T428/31605 ,  Y10T428/31609

摘要： A magnetic recording medium improved in electromagnetic characteristics, running durability and running properties is disclosed, comprising a non-magnetic support and at least one magnetic layer formed thereon, said magnetic layer having a ferromagnetic powder dispersed in a binder, wherein said magnetic layer contains at least one member selected from the group consisting of an aromatic phosphoric acid or a derivative thereof, an aromatic phosphonic acid or a derivative thereof, and an aromatic sulfonic acid or a derivative thereof, and wherein said ferromagnetic powder has a pH of at least 7, and said binder is a vinyl chloride copolymer having an epoxy group and a hydroxyl group attached to an alkyl chain group. Also, a method for producing a magnetic recording medium is disclosed which comprises the steps of kneading and dispersing a ferromagnetic powder having a pH of at least 7, at least one member selected from the group consisting of an aromatic phosphoric acid or a derivative thereof, an aromatic phosphonic acid or a derivative thereof, and an aromatic sulfonic acid or a derivative thereof, and a vinyl chloride copolymer having an epoxy group and a hydroxyl group attached to an alkyl chain group, together with a solvent; and then optionally adding at least one additive thereto, and mixing to prepare a magnetic coating; and then applying the resulting magnetic coating to a non-magnetic support; drying, calendering and then heat treating.

摘要翻译： 公开了一种提高电磁特性，运行耐久性和运行性能的磁记录介质，其包括非磁性支撑体和形成在其上的至少一个磁性层，所述磁性层具有分散在粘合剂中的铁磁粉末，其中所述磁性层包含在 选自芳香族磷酸或其衍生物，芳香族膦酸或其衍生物，芳香族磺酸或其衍生物的至少一种，其中所述铁磁粉末的pH至少为7， 并且所述粘合剂是具有连接到烷基链基团上的环氧基和羟基的氯乙烯共聚物。 另外，公开了一种制造磁记录介质的方法，该方法包括以下步骤：将pH至少为7的铁磁性粉末，至少一种选自芳族磷酸或其衍生物， 芳香族膦酸或其衍生物，芳香族磺酸或其衍生物，以及具有与烷基链基连接的环氧基和羟基的氯乙烯共聚物与溶剂; 然后任选地向其中加入至少一种添加剂，并混合以制备磁性涂层; 然后将所得的磁性涂层施加到非磁性载体上; 干燥，压延，然后热处理。

公开(公告)号：US4968557A

公开(公告)日：1990-11-06

申请号：US285976

申请日：1988-12-19

申请人： Kiyomi Ejiri ,  Yutaka Kakuishi ,  Hiroaki Araki

发明人： Kiyomi Ejiri ,  Yutaka Kakuishi ,  Hiroaki Araki

IPC分类号： C09D5/23 ,  C09D175/00 ,  C09D175/06 ,  G11B5/70 ,  G11B5/702 ,  G11B5/706 ,  G11B5/708

CPC分类号： G11B5/7085 ,  G11B5/70 ,  G11B5/702 ,  Y10S428/90 ,  Y10T428/25 ,  Y10T428/257 ,  Y10T428/30 ,  Y10T428/31609

摘要： A magnetic recording medium comprising a non-magnetic support having provided thereon a magnetic layer containing ferromagnetic alloy particles, fine particles of metal oxides and carbon black dispersed in a binder. The ferromagnetic alloy particles have a pH of from 4.5 to 7.5. The carbon black has a pH in a range of from 6.5 to 10.5. At least one kind of fine particles of metal oxides have Mohs' hardness of 5 or higher and pH of at least 3.5 but less than 7.5 and at least one kind of fine particles of metal oxides have Mohs' hardness of 5 or higher and a pH of from 7.5 to 10.5. The binder contains a polymer having at least one kind of an acidic polar group selected from the group consisting of a phosphate group, a phosphoric acid group, a sulfonic acid group, a carboxylic acid group, a metal salt of phosphoric acid group, a metal salt of sulfonic acid group, and a metal salt of carboxylic acid group.

摘要翻译： 一种磁记录介质，其包括非磁性载体，其上设有包含铁磁合金颗粒的磁性层，分散在粘合剂中的金属氧化物的细颗粒和炭黑。 铁磁合金颗粒的pH为4.5至7.5。 炭黑的pH在6.5至10.5的范围内。 金属氧化物的至少一种细颗粒的莫氏硬度为5以上，pH为至少3.5但小于7.5，并且至少一种金属氧化物微粒的莫氏硬度为5以上，pH为 从7.5到10.5。 粘合剂含有具有选自磷酸基，磷酸基，磺酸基，羧酸基，磷酸基金属盐，金属的金属中的至少一种酸性极性基团的聚合物 磺酸基盐和羧酸基金属盐。

公开(公告)号：US4959263A

公开(公告)日：1990-09-25

申请号：US195224

申请日：1988-05-18

申请人： Masashi Aonuma ,  Tsutomu Okita ,  Hiroshi Hashimoto ,  Hiroaki Araki ,  Kiyotaka Fukino ,  Kiyomi Ejiri

发明人： Masashi Aonuma ,  Tsutomu Okita ,  Hiroshi Hashimoto ,  Hiroaki Araki ,  Kiyotaka Fukino ,  Kiyomi Ejiri

IPC分类号： G11B5/702 ,  G11B5/712 ,  G11B5/714

CPC分类号： G11B5/7026 ,  G11B5/712 ,  G11B5/714 ,  Y10S428/90 ,  Y10T428/257

摘要： A magnetic recording medium is described, comprising a nonmagnetic support having thereon a magnetic layer containing a binder which is cross-linkable or polymerizable by radiation irradiation and ferromagnetic particles, the ferromagnetic particles being metal or metal alloy particles mainly comprising iron having a crystal size of 300 .ANG. or less, having an atomic ratio of oxygen atoms to iron atoms of from 1.6 to 3.0 on the surface of the particles, and the magnetic layer having been irradiated with radiation, and comprising a nonmagnetic support having thereon a magnetic layer containing a binder comprising thermoplastic resins, thermosetting resins, reactive type resins and mixtures thereof and ferromagnetic particles, said ferromagnetic particles being metal or metal alloy particles mainly comprising iron having a crystal size of 250 .ANG. or less, and having an atomic ratio of oxygen atoms to iron atoms of from 1.6 to 3.0 on the surface of said particles.

摘要翻译： 描述了一种磁记录介质，其包括其上具有含有可通过辐射照射和铁磁性颗粒可交联或可聚合的粘合剂的磁性层的非磁性载体，所述铁磁颗粒是主要包含具有晶体尺寸的铁的金属或金属合金颗粒 300或更小，在颗粒表面上的氧原子与铁原子的原子比为1.6至3.0，并且已经辐照辐照的磁性层，并且包含其上具有含有粘合剂的磁性层的非磁性载体 包括热塑性树脂，热固性树脂，反应型树脂及其混合物和铁磁颗粒，所述铁磁性颗粒是主要包含结晶尺寸为250或更小的铁并且具有氧原子与铁原子的原子比的金属或金属合金颗粒 在所述颗粒的表面上为1.6至3.0。

公开(公告)号：US4885208A

公开(公告)日：1989-12-05

申请号：US81513

申请日：1987-08-05

申请人： Hiroaki Araki ,  Kiyomi Ejiri ,  Takao Ohya

发明人： Hiroaki Araki ,  Kiyomi Ejiri ,  Takao Ohya

IPC分类号： G11B5/708 ,  C09D5/23 ,  C09D127/04 ,  C09D127/06 ,  C09D175/00 ,  C09D175/04 ,  G11B5/70 ,  G11B5/702

CPC分类号： G11B5/7028 ,  G11B5/7013 ,  Y10S428/90 ,  Y10T428/2991

摘要： A magnetic recording medium comprising a nonmagnetic support and a magnetic recording layer provided on the support, wherein the magnetic recording layer contains a compound having a polar group (i.e., a carboxylic acid group, a carboxylic acid salt group, a sulfonic acid group or a sulfonic acid salt group) which is bonded to an aromatic ring directly or indirectly through a polymethylene group having not more than 4 carbon atoms or an unsaturated straight-chain hydrocarbon group having not more than 4 carbon atoms.

摘要翻译： 一种磁记录介质，包括设置在载体上的非磁性载体和磁记录层，其中磁记录层含有具有极性基团的化合物（即，羧酸基，羧酸盐基，磺酸基或 磺酸盐基），其直接或间接通过具有不超过4个碳原子的多亚甲基或不超过4个碳原子的不饱和直链烃基键合到芳族环上。

公开(公告)号：US4801505A

公开(公告)日：1989-01-31

申请号：US110294

申请日：1987-10-20

申请人： Kiyomi Ejiri ,  Hiroaki Araki ,  Akihiro Matsufuji ,  Akira Kasuga

发明人： Kiyomi Ejiri ,  Hiroaki Araki ,  Akihiro Matsufuji ,  Akira Kasuga

IPC分类号： G11B5/702 ,  G11B5/708 ,  G11B5/712

CPC分类号： G11B5/7085 ,  G11B5/702 ,  Y10S428/90 ,  Y10T428/25 ,  Y10T428/256 ,  Y10T428/257 ,  Y10T428/2991 ,  Y10T428/2993 ,  Y10T428/31609 ,  Y10T428/31935

摘要： A magnetic recording medium contains in its magnetic recording layer a ferromagnetic metal powder containing an aluminum component in an amount of 1 to 6% by weight as alumnum metal, and an extremely hard abrasive such as .alpha.-alumina, chrome oxide, silicon carbide and silicon nitride. A magnetic recording medium preferably contains in its magnetic recording layer a binder comprising a resin component having a polar group.

摘要翻译： 磁记录介质在其磁记录层中含有含有1至6重量％的铝组分的铁磁金属粉末作为金属金属，以及极硬的研磨剂如α-氧化铝，氧化铬，碳化硅和硅 氮化物。 磁记录介质优选在其磁记录层中含有包含具有极性基团的树脂组分的粘合剂。

公开(公告)号：US4759979A

公开(公告)日：1988-07-26

申请号：US927464

申请日：1986-11-06

申请人： Hideaki Kosha ,  Kiyomi Ejiri

发明人： Hideaki Kosha ,  Kiyomi Ejiri

IPC分类号： C09D5/23 ,  C09D7/12 ,  G11B5/708

CPC分类号： G11B5/708 ,  Y10S428/90 ,  Y10T428/25 ,  Y10T428/256 ,  Y10T428/257

摘要： A magnetic recording medium is disclosed which comprises a non-magnetic support having coated thereon a magnetic layer containing a specific amount of a specific acicular Cr.sub.2 O.sub.3 along with alpha-Al.sub.2 O.sub.3, SiC, and/or TiC, which medium shows excellent surface properties and electromagnetic properties, as well as improved running durability.

摘要翻译： 公开了一种磁记录介质，其包括其上涂覆有含有特定量的特定针状Cr 2 O 3以及α-Al 2 O 3，SiC和/或TiC的磁性层的非磁性载体，该介质显示出优异的表面性质和电磁特性 ，以及改善运行耐久性。

公开(公告)号：US4729922A

公开(公告)日：1988-03-08

申请号：US929316

申请日：1986-11-12

申请人： Kiyomi Ejiri ,  Hideaki Kosha ,  Akihiro Matsufuji

发明人： Kiyomi Ejiri ,  Hideaki Kosha ,  Akihiro Matsufuji

IPC分类号： G11B5/702 ,  G11B5/708 ,  G11B5/70

CPC分类号： G11B5/708 ,  G11B5/7021 ,  Y10S428/90 ,  Y10T428/25 ,  Y10T428/256

摘要： A magnetic recording medium comprises a non-magnetic support having provided thereon a magnetic layer containing magnetic particles dispersed in a binder. The magnetic layer contains acicular Cr.sub.2 O.sub.3 having an average length in the long axis of 1.0 .mu.m or less, an average length in the short axis of 0.1 .mu.m or less and an acicular ratio (long axis/short axis) of from 5/1 to 20/1 in an amount of from 1 to 20 wt % based on the total weight of the magnetic particles. The binder comprises at least one material selected from the group consisting of polyurethane having a glass transition temperature (Tg) of from 0.degree. to 95.degree. C. or containing a metal sulfonate group, or a vinyl chloride resin containing a metal sulfonate group.

摘要翻译： 磁记录介质包括非磁性载体，其上设有包含分散在粘合剂中的磁性颗粒的磁性层。 磁性层含有长轴的平均长度为1.0μm以下，短轴的平均长度为0.1μm以下，针状比（长轴/短轴）为5/1的针状Cr 2 O 3 至20/1，其量为1至20重量％，基于磁性颗粒的总重量。 粘合剂包含选自玻璃化转变温度（Tg）为0〜95℃或含有金属磺酸盐基团的聚氨酯或含有金属磺酸盐基的氯乙烯树脂的至少一种材料。