公开(公告)号：US5494749A

公开(公告)日：1996-02-27

申请号：US307284

申请日：1994-09-16

申请人： Osamu Kubo ,  Tatsumi Maeda ,  Tutomu Nomura ,  Shunji Kurisu ,  Etsuji Ogawa

发明人： Osamu Kubo ,  Tatsumi Maeda ,  Tutomu Nomura ,  Shunji Kurisu ,  Etsuji Ogawa

IPC分类号： G11B5/706 ,  B32B5/16

CPC分类号： G11B5/70678 ,  Y10S428/90 ,  Y10T428/2982

摘要： A magnetic powder for magnetic recording is disclosed which comprises composite magnetic particles (A), each of which contains hexagonal ferrite and spinel structure ferrite, and single phase magnetic particles of hexagonal ferrite (B). When the mixing ratio [(A):(B)] of (A) and (B) in the range from 5:95 to 95:5, remarkable effect can be obtained. Especially, when the mixing ratio of (A) and (B) is in the range from 5:95 to 30:70, the dispersion property is improved due to disturbance of magnetic stacking. Thus, the magnetic powder in this mixing ratio is particularly suitable for magnetic recording in a short wavelength range. When the mixing ratio of (A) and (B) is in the range from 70:30 to 95:5, the reproduction output is improved due to activation of (A). Thus, the magnetic powder in this mixing ratio is specifically suitable for magnetic recording in a long wavelength range. By containing the magnetic powder described above, a perpendicular magnetic recording medium with high electromagnetic characteristics, particularly a high S/N ratio and a low noise can be obtained.

摘要翻译： 公开了一种用于磁记录的磁粉，其包含复合磁性颗粒（A），每个复合磁性颗粒包含六方晶系铁氧体和尖晶石结构铁氧体，以及六方晶系铁氧体的单相磁性颗粒（B）。 当（A）和（B）的混合比[（A）：（B）]在5:95至95:5的范围内时，可以获得显着的效果。 特别是，当（A）和（B）的混合比在5:95至30:70的范围内时，由于磁性堆叠的干扰，分散性能得到改善。 因此，这种混合比的磁粉特别适用于短波长范围内的磁记录。 当（A）和（B）的混合比在70:30至95:5的范围内时，由于（A）的激活，再现输出被改善。 因此，该混合比例的磁粉特别适用于长波长范围的磁记录。 通过含有上述磁粉，可以获得具有高电磁特性，特别是高S / N比和低噪声的垂直磁记录介质。

公开(公告)号：US5378547A

公开(公告)日：1995-01-03

申请号：US869298

申请日：1992-04-16

申请人： Osamu Kubo ,  Tatsumi Maeda ,  Tutomu Nomura ,  Shunji Kurisu ,  Etsuji Ogawa

发明人： Osamu Kubo ,  Tatsumi Maeda ,  Tutomu Nomura ,  Shunji Kurisu ,  Etsuji Ogawa

IPC分类号： C01G49/00 ,  C09D5/23 ,  C09D7/12 ,  G11B5/706 ,  H01F1/047 ,  G11B5/66

CPC分类号： G11B5/70678 ,  Y10S428/90 ,  Y10T428/2982

摘要： A magnetic powder for magnetic recording is disclosed which comprises composite type magnetic particles (A), each of which contains hexagonal ferrite and spinel structure ferrite, and single phase type magnetic particles of hexagonal ferrite (B). When the mixing ratio of (A) and (B) in the range from 5:95 to 95:5, remarkable effect can be obtained. Especially, when the mixing ratio of (A) and (B) is in the range from 5:95 to 30:70, the dispersion property is improved due to disturbance of magnetic stacking. Thus, the magnetic powder in this mixing ratio is particularly suitable for magnetic recording in a short wavelength range. When the mixing ratio of (A) and (B) is in the range 70: 30 to 95:5, the reproduction output is improved due to activation of (A) . Thus, the magnetic powder in this mixing ratio is specifically suitable for magnetic recording in a long wavelength range. By containing the magnetic powder described above, a perpendicular magnetic recording medium with high electromagnetic characteristics, particularly a high S/N ratio and a low noise can be obtained.

摘要翻译： 公开了一种用于磁记录的磁粉，其包括复合型磁性颗粒（A），每个复合型磁性颗粒包含六方晶系铁氧体和尖晶石结构铁氧体，以及六方晶系铁氧体（B）的单相型磁性颗粒。 当（A）和（B）的混合比在5:95至95:5的范围内时，可以获得显着的效果。 特别是，当（A）和（B）的混合比在5:95至30:70的范围内时，由于磁性堆叠的干扰，分散性能得到改善。 因此，这种混合比的磁粉特别适用于短波长范围内的磁记录。 当（A）和（B）的混合比在70:30至95:5的范围内时，由于（A）的激活，再现输出被改善。 因此，该混合比例的磁粉特别适用于长波长范围的磁记录。 通过含有上述磁粉，可以获得具有高电磁特性，特别是高S / N比和低噪声的垂直磁记录介质。

公开(公告)号：US4493874A

公开(公告)日：1985-01-15

申请号：US473200

申请日：1983-03-08

申请人： Osamu Kubo ,  Tadashi Ido ,  Tutomu Nomura ,  Tatsumi Maeda

发明人： Osamu Kubo ,  Tadashi Ido ,  Tutomu Nomura ,  Tatsumi Maeda

IPC分类号： C01G49/00 ,  C01G51/00 ,  C03C10/00 ,  G11B5/706 ,  G11B5/712 ,  H01F1/11 ,  C04B35/26

CPC分类号： B82Y30/00 ,  C01G49/0036 ,  C01G49/009 ,  C01G51/006 ,  C03C10/0081 ,  G11B5/70678 ,  G11B5/712 ,  H01F1/11 ,  C01P2002/54 ,  C01P2004/54 ,  C01P2004/62 ,  C01P2004/64 ,  C01P2006/12 ,  C01P2006/42 ,  C01P2006/80 ,  Y10S428/90 ,  Y10T428/2991 ,  Y10T428/2996

摘要： A hexagonal ferrite magnetic powder for high density magnetic recording, having an improved dispersibility in a binder or paint is obtained by melting a mixture of hexagonal ferrite-forming components and a glass-forming component, and rapidly cooling the resultant molten mixture to obtain an amorphous material. The amorphous material is thermally treated to precipitate fine particles of the hexagonal ferrite therein. The amorphous material containing the precipitated fine particles is dissolved such that the glass-forming component remains on each of said fine particles in an amount of 0.01 to 0.3% by weight based on the weight of the particles.

摘要翻译： 通过熔融六方晶系铁氧体形成组分和玻璃形成组分的混合物，可以获得在粘合剂或涂料中具有改进的分散性的用于高密度磁记录的六角铁氧体磁粉，并快速冷却所得到的熔融混合物以获得无定形 材料。 将无定形材料进行热处理以使其中的六方晶系铁氧体的细颗粒析出。 含有沉淀的细颗粒的无定形材料被溶解，使得玻璃形成组分基于颗粒的重量以0.01至0.3重量％的量残留在每个所述细颗粒上。

公开(公告)号：US4606971A

公开(公告)日：1986-08-19

申请号：US639317

申请日：1984-08-10

申请人： Tadashi Ido ,  Osamu Kubo ,  Masahiro Fukasawa ,  Tatsumi Maeda ,  Tutomu Nomura

发明人： Tadashi Ido ,  Osamu Kubo ,  Masahiro Fukasawa ,  Tatsumi Maeda ,  Tutomu Nomura

IPC分类号： G11B5/706 ,  C09D5/23 ,  C09D7/12 ,  G11B5/70 ,  G11B5/714

CPC分类号： G11B5/714 ,  Y10S428/90 ,  Y10T428/256 ,  Y10T428/257

摘要： Disclosed is a magnetic recording medium comprised of a substrate and a layer of magnetic powder coated on a surface of the substrate, characterized in that the magnetic powder is hexagonal crystals having single domain crystalline magnetic anisotropy, particle sizes of 0.01 to 0.3 .mu.m, particle size/thickness ratios of 2.3 to 15 and the tapping packing rate of said magnetic powder is 15% or more.

摘要翻译： 公开了一种磁性记录介质，由基材和涂覆在基材表面上的一层磁粉组成，其特征在于，磁粉是具有单结晶磁各向异性的六方晶体，粒径为0.01〜0.3μm，粒径为 尺寸/厚度比为2.3至15，所述磁粉的攻丝包装率为15％以上。

公开(公告)号：US5077146A

公开(公告)日：1991-12-31

申请号：US250576

申请日：1988-09-29

申请人： Osamu Kubo ,  Tutomu Nomura ,  Tadashi Ido ,  Hirotaka Yokoyama

发明人： Osamu Kubo ,  Tutomu Nomura ,  Tadashi Ido ,  Hirotaka Yokoyama

IPC分类号： G11B5/706

CPC分类号： G11B5/70678 ,  Y10S428/90

摘要： Disclosed is a magnetic powder for high-density magnetic recording, formed of a substituted hexagonal ferrite possessing an average particle diameter in the range of 0.01 to 0.2 .mu.m and a coercivity in the range of 200 to 2,000 Oe and characterized by the fact that the substituted hexagonal ferrite has at least 0.05 to 0.5 atom of at least one element selected from the group consisting of Zr and Hf per chemical formula and at least one element selected from among the elements other than Zr and Hf substituted for part of the Fe atom of the ferrite, and a magnetic recording medium of the present invention comprises a substrate and the magnetic powder mentioned above deposited on the substrate. Since the magnetic powder comprises very minute particles, the magnetic powder and the magnetic recording medium are capable of high-density recording. The magnetic powder has an improved desirably controlled aspect ratio for orientation and the temperature characteristic of coercivity (Hc) as compared with the countertype formed of a hexagonal ferrite which has neither Zr nor Hf substituted for the Fe atom.

公开(公告)号：US4636433A

公开(公告)日：1987-01-13

申请号：US795130

申请日：1985-11-05

申请人： Osamu Kubo ,  Tutomu Nomura ,  Tadashi Ido ,  Hirotaka Yokoyama

发明人： Osamu Kubo ,  Tutomu Nomura ,  Tadashi Ido ,  Hirotaka Yokoyama

IPC分类号： C01G49/00 ,  C04B35/26 ,  C09D5/23 ,  C09D7/12 ,  G11B5/706 ,  H01F1/11 ,  G11B5/70

CPC分类号： C04B35/2633 ,  G11B5/70678 ,  Y10T428/256 ,  Y10T428/257 ,  Y10T428/2978

摘要： A magnetic powder for magnetic recording media comprises a hexagonal crystalline system ferrite containing, as essential components for said hexagonal crystalline system ferrite, iron and oxygen, and at least one of the elements selected from the group of Ba, Sr, Ca and Pb, said iron being substituted by at least one of the elements selected from the group of Ti, Co, Ni, Mn, Cu, Zn, In, Ge, Nb, Zr and Sb; and at least one of Ba, Sr, Ca, Pb being substituted by at least one of the rare earth elements selected from the group of Ce, Pr, Nd, Pm, Sm and Eu. The magnetic powder has a mean particle size of 0.01 to 0.3 .mu.m and a coercive force of 200 and 2000 Oe. The magnetic powder is improved in its saturation magnetization while retaining a suitable coercive force. Accordingly, high reproduction output can be obtained in a magnetic recording medium employing the magnetic powder.

摘要翻译： 用于磁记录介质的磁性粉末包括六方晶系铁氧体，其包含作为所述六方晶系铁素体，铁和氧以及选自Ba，Sr，Ca和Pb中的至少一种元素的必要组分，所述六方晶系铁氧体包含所述六方晶系铁氧体， 铁被选自Ti，Co，Ni，Mn，Cu，Zn，In，Ge，Nb，Zr和Sb中的至少一种元素取代; 并且Ba，Sr，Ca，Pb中的至少一种被选自Ce，Pr，Nd，Pm，Sm和Eu中的至少一种稀土元素取代。 磁粉的平均粒径为0.01〜0.3μm，矫顽力为200〜2000Oe。 磁性粉末在保持适当的矫顽力的同时提高其饱和磁化强度。 因此，在使用磁性粉末的磁记录介质中可以获得高再现输出。

公开(公告)号：US4341648A

公开(公告)日：1982-07-27

申请号：US203153

申请日：1980-11-03

申请人： Osamu Kubo ,  Tadashi Ido ,  Tutomu Nomura ,  Koichiro Inomata

发明人： Osamu Kubo ,  Tadashi Ido ,  Tutomu Nomura ,  Koichiro Inomata

IPC分类号： G11B5/706 ,  C01G49/00 ,  C01G51/00 ,  C04B35/26 ,  C09D5/23 ,  C09D7/12 ,  H01F1/11

CPC分类号： B82Y30/00 ,  C01G49/0036 ,  C01G49/009 ,  C01G51/006 ,  C04B35/2683 ,  C01P2002/54 ,  C01P2004/03 ,  C01P2004/54 ,  C01P2004/62 ,  C01P2004/64 ,  C01P2006/42

摘要： A method for preparing a magnetic powder for high density magnetic recording includes melting a mixture containing the fundamental component of a hexagonal ferrite, a substituting component for reducing the coercive force, and a glass forming material. The resultant molten material is rapidly cooled to obtain an amorphous body which is then heat-treated to produce desired substituted type hexagonal ferrite particles in the glass matrix.

摘要翻译： 制备用于高密度磁记录的磁粉的方法包括熔化包含六方晶系铁氧体的基本成分的混合物，用于降低矫顽力的取代成分和玻璃形成材料。 将所得熔融材料快速冷却以获得非晶体，然后将其进行热处理以在玻璃基体中产生所需的取代型六方晶系铁氧体颗粒。

公开(公告)号：US4569775A

公开(公告)日：1986-02-11

申请号：US417441

申请日：1982-09-08

申请人： Osamu Kubo ,  Tadashi Ido ,  Tutomu Nomura ,  Koichiro Inomata

发明人： Osamu Kubo ,  Tadashi Ido ,  Tutomu Nomura ,  Koichiro Inomata

IPC分类号： C01G49/00 ,  C01G51/00 ,  G11B5/706 ,  H01F1/11 ,  C04B35/26

CPC分类号： B82Y30/00 ,  C01G49/0018 ,  C01G49/0036 ,  C01G51/006 ,  G11B5/70678 ,  C01P2004/54 ,  C01P2004/62 ,  C01P2004/64 ,  C01P2006/42

摘要： A method for preparing a magnetic powder for high density magnetic recording includes melting a mixture containing the fundamental component of a hexagonal ferrite, a substituting component for reducing the coercive force, and boron trioxide as a glass forming substance in predetermined amounts. The resultant molten material is rapidly cooled to obtain an amorphous body which is then heat-treated to produce desired substituted type hexagonal ferrite particles in the glass matrix.

摘要翻译： 制备用于高密度磁记录的磁粉的方法包括将含有六方晶系铁氧体的基本组分的混合物，用于降低矫顽力的取代组分和作为玻璃形成物质的三氧化硼的预定量的混合物熔化。 将所得熔融材料快速冷却以获得非晶体，然后将其进行热处理以在玻璃基体中产生所需的取代型六方晶系铁氧体颗粒。

公开(公告)号：US5104750A

公开(公告)日：1992-04-14

申请号：US501719

申请日：1990-03-30

申请人： Osamu Kubo ,  Tutomu Nomura ,  Tadashi Ido

发明人： Osamu Kubo ,  Tutomu Nomura ,  Tadashi Ido

IPC分类号： C09D5/23 ,  C09D7/12 ,  G11B5/70 ,  G11B5/706

CPC分类号： G11B5/70678 ,  Y10S428/90

摘要： In the magnetic recording medium according to the present invention comprising a magnetic recording medium layer where a magnetic paint containing Ba ferrite magnetic powder is coated on the substrate, Hc in the oriented direction ranging from 900 to 1500 Oe, the squareness in the oriented direction being 0.80 or more, and the ratio Hr(90.degree.)/Hr(0.degree.) of the remanence coercive force Hr(0.degree.) in the oriented direction (0.degree.) and the remanence coercive force Hr (90.degree.) in the direction (90.degree.) perpendicular to the oriented direction ranging from 1

公开(公告)号：US4582623A

公开(公告)日：1986-04-15

申请号：US646165

申请日：1984-08-31

申请人： Osamu Kubo ,  Tutomu Nomura ,  Tadashi Ido

发明人： Osamu Kubo ,  Tutomu Nomura ,  Tadashi Ido

IPC分类号： C01G49/00 ,  C01G49/02 ,  G11B5/706 ,  H01F1/10 ,  H01F1/11 ,  C04B35/36

CPC分类号： G11B5/70678

摘要： Disclosed is a barium ferrite magnetic powder comprising particles characterized by (A) a mean particle size of 0.3 .mu.m or smaller and (B) the presence of Sr, Ca and Si in respective amounts of 0.2 wt. % or less as SrO, 0.15 wt. % or less as CaO, and 0.3 wt. % or less as SiO.sub.2. Also disclosed is a recording medium comprising the barium ferrite magnetic powder.

摘要翻译： 公开了一种钡铁氧体磁粉，其特征在于，（A）平均粒径为0.3μm以下，（B）Sr，Ca，Si的存在量分别为0.2重量％ ％以下，SrO 0.15％ ％以下，CaO为0.3重量％以下。 ％以下。 还公开了包含钡铁氧体磁性粉末的记录介质。