公开(公告)号：US06346310B1

公开(公告)日：2002-02-12

申请号：US09600833

申请日：2000-12-19

申请人： Koji Naoe ,  Tatsuo Ishikawa ,  Hiroaki Takano

发明人： Koji Naoe ,  Tatsuo Ishikawa ,  Hiroaki Takano

IPC分类号： G11B5735

CPC分类号： G11B5/735 ,  Y10S428/90 ,  Y10T428/24355 ,  Y10T428/25 ,  Y10T428/256 ,  Y10T428/257 ,  Y10T428/265 ,  Y10T428/31609 ,  Y10T428/31721

摘要： Disclosed is a magnetic recording medium comprising a magnetic layer on a surface of a flexible support and a backcoat layer on the opposite surface, characterized in that the backcoat layer comprises a granulated oxide consisting of titanium oxide, &agr;-iron oxide or a mixture thereof and carbon black in the weight ratio ranging from 60/40 to 90/10, and further comprises a binder in an amount ranging from 10 to 40 parts by weight with respect to 100 parts by weight of the total amount of the granulated oxide and carbon black. The magnetic recording medium of the present invention is characterized in that both the running durability and electromagnetic characteristics are excellent.

摘要翻译： 公开了一种磁性记录介质，其包括在柔性载体的表面上的磁性层和相对表面上的背涂层，其特征在于，背涂层包含由氧化钛，α-氧化铁或其混合物组成的颗粒状氧化物，以及 炭黑，重量比为60/40至90/10，并且还包含相对于100重量份的颗粒状氧化物和炭黑的总量为10至40重量份的粘合剂 。 本发明的磁记录介质的特征在于运行耐久性和电磁特性均优异。

公开(公告)号：US5718964A

公开(公告)日：1998-02-17

申请号：US738727

申请日：1996-10-28

申请人： Koji Naoe ,  Kiyomi Ejiri ,  Hiroaki Takano

发明人： Koji Naoe ,  Kiyomi Ejiri ,  Hiroaki Takano

IPC分类号： G11B5/70 ,  G11B5/708

CPC分类号： G11B5/70 ,  G11B5/708 ,  Y10T428/24355 ,  Y10T428/25 ,  Y10T428/256

摘要： A magnetic recording medium is disclosed, comprising a flexible non-magnetic medium having on at least one surface thereof a magnetic layer comprising a ferromagnetic powder dispersed in a binder, wherein the heights and the existing densities of the abrasive projections and the non-abrasive projections on the surface of the magnetic layer are defined in the specific ranges. The magnetic recording medium are excellent in the electromagnetic characteristics, the magnetic head abrasion resistance, and the running durability.

摘要翻译： 公开了一种磁记录介质，包括柔性非磁性介质，其至少在其一个表面上具有分散在粘合剂中的铁磁粉末的磁性层，其中研磨突起和非研磨突起的高度和现有密度 在磁性层的表面上限定在特定范围内。 磁记录介质具有优异的电磁特性，磁头耐磨性和运行耐久性。

公开(公告)号：US6074724A

公开(公告)日：2000-06-13

申请号：US918864

申请日：1997-08-26

申请人： Hiroo Inaba ,  Kiyomi Ejiri ,  Masaki Suzuki ,  Koji Naoe ,  Yuichiro Murayama ,  Hiroaki Takano

发明人： Hiroo Inaba ,  Kiyomi Ejiri ,  Masaki Suzuki ,  Koji Naoe ,  Yuichiro Murayama ,  Hiroaki Takano

IPC分类号： G11B5/702 ,  G11B5/706

CPC分类号： B82Y15/00 ,  G11B5/7021 ,  G11B5/7022 ,  G11B5/70621 ,  Y10S428/90 ,  Y10T428/24355 ,  Y10T428/25 ,  Y10T428/257 ,  Y10T428/265

摘要： A magnetic recording medium is disclosed, which comprises a support having thereon a magnetic layer comprising a binder and a ferromagnetic powder dispersed therein, wherein said binder comprises a polyurethane resin having at least one cyclic hydrocarbon group and at least one ether linkage, and said ferromagnetic powder is a ferromagnetic metallic powder which comprises Fe and has a mean major-axis length of from 0.05 to 0.19 .mu.m and a crystallite size of from 100 to 230 .ANG.; and further a magnetic recording medium is disclosed, comprising a support having thereon in succession an undercoat layer comprising a binder U and an inorganic powder dispersed therein and a magnetic layer comprising a binder M and a ferromagnetic powder dispersed therein, wherein at least either of the binder U or M comprises a polyurethane resin having at least one cyclic hydrocarbon group and at least one ether linkage and said ferromagnetic powder is a ferromagnetic metallic powder which comprises Fe and has a mean major-axis length of from 0.05 to 0.19 .mu.m and a crystallite size of from 100 to 230 .ANG..

摘要翻译： 公开了一种磁记录介质，其包括其上具有包含粘合剂和分散在其中的铁磁粉末的磁性层的载体，其中所述粘合剂包含具有至少一个环状烃基和至少一个醚键的聚氨酯树脂，并且所述铁磁性 粉末是含铁的铁磁性金属粉末，其平均长轴长度为0.05至0.19μm，微晶尺寸为100至230安培; 并且还公开了一种磁记录介质，包括其上连续地具有包含粘合剂U和分散在其中的无机粉末的底涂层的支撑体和包含粘合剂M和分散在其中的铁磁性粉末的磁性层，其中， 粘合剂U或M包含具有至少一个环状烃基和至少一个醚键的聚氨酯树脂，并且所述铁磁性粉末是包含Fe并且具有0.05至0.19μm的平均长轴长度的铁磁性金属粉末，以及 微晶尺寸为100至230安培。

公开(公告)号：US5447782A

公开(公告)日：1995-09-05

申请号：US143063

申请日：1993-10-29

申请人： Hiroo Inaba ,  Kiyomi Ejiri ,  Koji Naoe

发明人： Hiroo Inaba ,  Kiyomi Ejiri ,  Koji Naoe

IPC分类号： C09D5/23 ,  G11B5/70 ,  G11B5/716 ,  G11B5/73 ,  G11B5/738 ,  G11B5/00

CPC分类号： G11B5/70 ,  G11B5/716 ,  G11B5/738 ,  Y10S428/90 ,  Y10T428/24942 ,  Y10T428/2495 ,  Y10T428/24967 ,  Y10T428/256 ,  Y10T428/257

摘要： Disclosed is a magnetic recording medium, comprising (a) a nonmagnetic flexible support, (b) a lower nonmagnetic layer provided on the support and comprising a nonmagnetic particle and a binder, and (c) a magnetic layer provided on the nonmagnetic layer and comprising a ferromagnetic particle and a binder, wherein (i) the magnetic layer comprises at least two layers comprising a lower magnetic layer provided on the lower nonmagnetic layer and an upper magnetic layer provided on the lower magnetic layer, (ii) a ratio of the lower nonmagnetic layer thickness to the total magnetic layer thickness of the lower magnetic layer and the upper magnetic layer is from 1 to 50, (iii) the upper magnetic layer and the lower magnetic layer have a difference in coercive force of at least 80 Oe, and (iv) the lower nonmagnetic layer and at least the lower magnetic layer are formed by a wet-on-wet coating method.

摘要翻译： 公开了一种磁记录介质，包括（a）非磁性柔性支撑体，（b）设置在载体上的下部非磁性层，并且包括非磁性颗粒和粘合剂，和（c）设置在非磁性层上的磁性层， 铁磁颗粒和粘合剂，其中（i）磁性层包括至少两层，包括设置在下部非磁性层上的下部磁性层和设置在下部磁性层上的上部磁性层，（ii）下部磁性层的比例 非磁性层厚度与下部磁性层和上部磁性层的总磁性层厚度的比值为1〜50，（iii）上部磁性层和下部磁性层的矫顽力差异至少为80 Oe， （iv）下部非磁性层和至少下部磁性层通过湿式湿式涂覆法形成。

公开(公告)号：US06680088B2

公开(公告)日：2004-01-20

申请号：US10151998

申请日：2002-05-22

申请人： Koji Naoe ,  Hiroyuki Kobayashi

发明人： Koji Naoe ,  Hiroyuki Kobayashi

IPC分类号： B05D300

CPC分类号： G11B5/842

摘要： A process for producing a magnetic recording medium is provided in which a magnetic layer including a ferromagnetic powder and a binder is provided on a non-magnetic flexible support. In the process, a magnetic liquid containing mainly a ferromagnetic powder and a binder, and an abrasive liquid paste including an abrasive and a binder are prepared separately, and the abrasive liquid paste is subsequently subjected to an ultrasonic dispersion treatment and then mixed with the magnetic liquid to prepare a magnetic coating solution for the magnetic layer.

摘要翻译： 提供了一种用于制造磁记录介质的方法，其中在非磁性柔性支撑件上设置包括铁磁性粉末和粘合剂的磁性层。 在此过程中，分别制备主要含有铁磁性粉末和粘合剂的磁性液体，以及包含研磨剂和粘合剂的研磨液体糊剂，然后对研磨液糊进行超声波分散处理，然后与磁性混合 液体以制备用于磁性层的磁性涂层溶液。

公开(公告)号：US06203934B1

公开(公告)日：2001-03-20

申请号：US09169189

申请日：1998-10-08

申请人： Koji Naoe ,  Kiyomi Ejiri ,  Naoto Abe

发明人： Koji Naoe ,  Kiyomi Ejiri ,  Naoto Abe

IPC分类号： G11B566

CPC分类号： G11B5/738 ,  G11B5/70 ,  G11B5/70621

摘要： A magnetic recording medium is described, which comprises a support having thereon a magnetic layer comprising a ferromagnetic metal powder and a binder resin, wherein the coercive force (Hc) of the magnetic layer is from 2,100 to 3,000 Oe, SFD (switching field distribution) of the magnetic layer is 0.30 or less, and an average thickness: d of the magnetic layer is in the range of: d≦ recording wavelength &lgr;/4.

摘要翻译： 描述了一种磁记录介质，其包括其上具有包含铁磁性金属粉末和粘合剂树脂的磁性层的支撑体，其中磁性层的矫顽力（Hc）为2100〜3000Oe，SFD（切换场分布） 的磁性层的平均厚度d在以下的范围内：d <=记录波长lambd / 4。

公开(公告)号：US06602576B2

公开(公告)日：2003-08-05

申请号：US09798807

申请日：2001-03-02

申请人： Koji Naoe ,  Kiyomi Ejiri

发明人： Koji Naoe ,  Kiyomi Ejiri

IPC分类号： G11B566

CPC分类号： G11B5/738 ,  G11B5/70 ,  G11B5/7021 ,  G11B5/70621 ,  G11B5/714 ,  Y10S428/90 ,  Y10T428/24355 ,  Y10T428/24942 ,  Y10T428/24975 ,  Y10T428/265 ,  Y10T428/31609

摘要： The present invention aims to provide a magnetic recording medium for digital recording/reproducing systems having a small bit area, i.e. a short recording wavelength and a narrow track width, which is a particulate magnetic recording medium showing good electromagnetic characteristics. A magnetic recording medium comprising a nonmagnetic layer containing a nonmagnetic powder and a binder and a magnetic layer containing a ferromagnetic powder and a binder provided in this order on a nonmagnetic substrate wherein said magnetic layer has an average thickness of 0.01-0.1 &mgr;m and the ratio of the area of magnetic recording defects generated upon magnetic development after recording at the shortest recording wavelength to the total magnetic recording area is 0.2-20%.

摘要翻译： 本发明的目的是提供一种用于数字记录/再现系统的磁记录介质，其具有小的位面积，即短记录波长和窄轨迹宽度，其是表现出良好电磁特性的微粒磁记录介质。 包含非磁性粉末和粘合剂的非磁性层和含有铁磁性粉末和粘合剂的磁性层按顺序设置在非磁性基材上，其中所述磁性层的平均厚度为0.01-0.1μm，磁性区域的比例 在以最短记录波长记录到总磁记录面积之后，在磁性显影时产生的记录缺陷为0.2-20％。

公开(公告)号：US06582815B2

公开(公告)日：2003-06-24

申请号：US10081093

申请日：2002-02-21

申请人： Koji Naoe ,  Kiyomi Ejiri

发明人： Koji Naoe ,  Kiyomi Ejiri

IPC分类号： G11B5708

CPC分类号： G11B5/708 ,  G11B5/714 ,  G11B5/842 ,  Y10T428/1164 ,  Y10T428/256 ,  Y10T428/265

摘要： Provided is a magnetic recording medium suitable for high density digital recording, in detail, a magnetic recording medium suitable for reproduction with an MR head. A magnetic recording medium comprising a nonmagnetic layer comprising a nonmagnetic powder and a binder and a magnetic layer comprising a ferromagnetic metal powder, a binder and a nonmagnetic powder provided in this order on a flexible nonmagnetic support. Said magnetic layer has an average thickness ranging from 0.01 to 0.2 &mgr;m, said ferromagnetic metal powder has a mean major axis length of less than 100 nm and a mean minor axis length of less than 20 nm, said nonmagnetic powder comprised in the magnetic layer is a granular or acicular nonmagnetic powder, the ratio of the mean particle size or minor axis length of said nonmagnetic powder to said mean minor axis length is higher than 0.2 and equal to or less than 2.5, and the maximum surface area of magnetic pinholes is equal to or less than 50% of a bit surface area.

公开(公告)号：US06534168B2

公开(公告)日：2003-03-18

申请号：US09938400

申请日：2001-08-23

申请人： Koji Naoe ,  Kiyomi Ejiri

发明人： Koji Naoe ,  Kiyomi Ejiri

IPC分类号： B32B516

CPC分类号： G11B5/738 ,  Y10S428/90 ,  Y10T428/257

摘要： Provided is a magnetic recording medium exhibiting a high C/N (low noise) ratio in high-density magnetic recording. A magnetic recording medium which comprises a nonmagnetic lower layer comprising a nonmagnetic powder and a binder and a magnetic layer comprising a ferromagnetic powder and a binder provided in this order on a flexible nonmagnetic support. The nonmagnetic lower layer comprises flat acicular &agr;-iron oxide powder with a major axis length ranging from 0.05 to 0.5 &mgr;m and a ratio of the major width to the minor width (major width/minor width) of the minor axis cross-section when sectioned at an angle perpendicular to the major axis is equal to or higher than 1. The granular nonmagnetic particles have a mean particle diameter equal to or less than 0.04 &mgr;m.

摘要翻译： 提供了一种在高密度磁记录中表现出高C / N（低噪声）比的磁记录介质。 一种磁记录介质，其包括非磁性粉末和粘合剂的非磁性下层和包含铁磁性粉末和粘合剂的磁性层，该磁性层按顺序设置在柔性非磁性载体上。 非磁性下层包括长轴长度为0.05-0.5μm的扁平针状α-氧化铁粉末，当切断时短轴截面的主宽度与较小宽度（主宽度/次宽度）的比率 垂直于长轴的角度等于或大于1.颗粒状非磁性颗粒的平均粒径等于或小于0.04μm。

公开(公告)号：US06428884B1

公开(公告)日：2002-08-06

申请号：US09602353

申请日：2000-06-23

申请人： Koji Naoe ,  Kiyomi Ejiri

发明人： Koji Naoe ,  Kiyomi Ejiri

IPC分类号： G11B5714

CPC分类号： G11B5/714 ,  G11B5/70 ,  G11B5/70621 ,  Y10T428/25 ,  Y10T428/265 ,  Y10T428/2982 ,  Y10T428/31609

摘要： Described is a magnetic recording medium comprising, on a flexible nonmagnetic support, a nonmagnetic layer containing a nonmagnetic powder and a binder, and a magnetic layer containing a ferromagnetic powder and a binder in this order. The average thickness, d, of the magnetic layer is from 0.01 to 0.3 &mgr;m, and the average particle number, m, of the ferromagnetic powder existing in the magnetic layer thickness direction is in the range of 1 to 20.

摘要翻译： 描述了一种磁性记录介质，其在柔性非磁性载体上包含依次包含非磁性粉末和粘合剂的非磁性层和含有铁磁粉末和粘合剂的磁性层。 磁性层的平均厚度d为0.01〜0.3μm，磁性层厚度方向上存在的铁磁性粉末的平均粒子数m为1〜20。