Fuji Photo Film Company, Limited

Fujifilm Corporation

Satoru Hayakawa

Hiroo Inaba

Shinji Saito

Kiyomi Ejiri

Toshio Kawamata

Kazuhiro Niitsuma

Yasushi Endo

Takao Ohya

Yasuo Nishikawa

Yutaka Kakuishi

Tadashi Ishiguro

Masaya Kojima

Hiroshi Hashimoto

Yasushi Hattori

Tsutomu Okita

Osamu Iwasaki

Toru Nakao

Yuichiro Murayama

Katsuhiko Meguro

Jun Nakagawa

Akira Kasuga

Masami Sato

Tatsuo Ishikawa

Minoru Sueki

Takeshi Nagata

Masataka Ota

A magnetic recording medium comprising: a magnetic layer; a first radiation curable resin layer; a non-magnetic support having an intrinsic viscosity of from 0.47 to 0.51 dL/g; and a second radiation curable resin layer, in this order, wherein the first radiation curable resin layer contains a filler, and the second radiation curable resin layer contains a filler.

Magnetic recording medium

A leader tape comprising a support and a coating layer containing powder and a binder, wherein at least one surface of the leader tape has a center line average surface roughness (Ra) of from 10 to 60 nm, and depression hardness (DH) defined by the following equation (1) of from 60 to 140 kg/mm(0.588 to 1.372 GPa):=3.7926&#xd7;10/()](kg/mm) &#x2003;&#x2003;(1)wherein Pmax is a maximum load and Hmax is a maximum displacement amount of an indenter.

Leader tape and magnetic tape cartridge using the same

A leader tape having: a support; an upper layer containing a powder, a binder, and a lubricant; and a lower layer containing a powder, a binder, and a lubricant which is at least 1.12 times as much as the lubricant of the upper layer; wherein the support, the lower layer, and the upper layer is in this order.

Leader tape and magnetic tape cartridge

A magnetic recording medium comprising: a support; a subbing layer comprising a radiation-curable resin; a nonmagnetic layer comprising a nonmagnetic powder and a binder; and at least one magnetic layer comprising a ferromagnetic powder and a binder, in this order, wherein the subbing layer has a thickness of from 0.05 to 1.0 &#x3bc;m, and the nonmagnetic powder has an average acicular ratio of 8 or more and has a form of a raft.

A cleaning medium for a magnetic recording apparatus is disclosed, comprising a nonmagnetic support having provided thereon a lower coating layer mainly containing a nonmagnetic inorganic powder and a binder, and a cleaning layer containing at least a ferromagnetic inorganic powder and a binder provided on the lower coating layer, wherein the thickness of the cleaning layer is from 0.05 to 1.0 &#x3bc;m, the thickness of the lower coating layer is from 0.2 to 5.0 &#x3bc;m, the thickness of the support is from 2.0 to 10 &#x3bc;m, and the thickness in total of the cleaning medium (cleaning tape) is from 4.0 to 15 &#x3bc;m.

Cleaning medium for magnetic recording apparatus

The magnetic tape processing method and apparatus allow at least one of a laser beam or laser beams in a visible region and a laser beam or laser beams in an ultraviolet region to be incident on a backing layer of a magnetic tape while transporting the magnetic tape in a lengthwise direction of the magnetic tape and process the backing layer by means of the laser beam or laser beams to form recesses on the backing layer. The processed magnetic tape is composed of a base layer, a magnetic layer formed on one surface of the base layer and the backing layer formed on another surface of the base layer and having recesses which are formed by processing the backing layer by means of the laser beam or laser beams. The method and apparatus can efficiently manufacture the magnetic tape having excellent characteristics such that the occurrence of the slip of the magnetic tape is not caused on a capstan roller and the like, even if the transportation speed of the tape is increased in a magnetic tape manufacturing apparatus, and furthermore a size of cupping of the magnetic tape is small.

Magnetic tape processing method and magnetic tape processing apparatus having an optical system

A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 &mgr;m and an average thickness variation (,d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising a binder having dispersed therein a ferromagnetic powder which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet, wherein the upper magnetic layer has an average dry thickness (d) of not more than 1.0 .mu.m and an average thickness variation (.sup..DELTA. d) at the interface between the upper magnetic layer and lower non-magnetic layer is not more than d/2. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

A magnetic recording medium is disclosed, comprising a non-magnetic support having provided thereon at least a lower non-magnetic layer comprising a binder having dispersed therein a non-magnetic powder and an upper magnetic layer comprising which has been coated on said lower non-magnetic layer while the lower non-magnetic layer is wet or in a dry state, wherein the coating solution for the lower non-magnetic layer having a thixotropic property and the lower non-magnetic layer containing either (a) an acicular inorganic powder having a Mohs hardness of 3 or more and a major axis length of 0.3 .mu.m or less or (b) a spherical inorganic powder other than carbon black having an average primary particle size of 0.08 .mu.m or less. The magnetic recording medium exhibits excellent electromagnetic characteristics, running properties, and durability.

A magnetic recording tape favorably employable for computer data storage has a flexible polymer web, a magnetic recording layer arranged on one surface side of the web, and a backing layer arranged on another surface side of the web, characterized in that the recording tape has a thickness of 2 to 8 .mu.m and shows a Young's modulus of not less than 1,200 kg/mm.sup.2 in its longitudinal direction; and the backing layer has a thickness of 0.2 to 1 .mu.m and is composed of a binder, a carbon black, a non-magnetic powder I having Mohs' scale of hardness of 3 to 4.5 and another non-magnetic powder II having Mohs' scale of hardness of 5 to 9. Between the magnetic layer and the flexible polymer web, a non-magnetic undercoating layer composed of a binder and a non-magnetic powder can be provided.

Magnetic recording tape favorably employable for computer data storage

A magnetic recording tape favorably employable for computer data storage has a flexible polymer web, a magnetic recording layer arranged on one surface side of the web via a non-magnetic undercoating layer, and a back-coating layer arranged on another surface side of the web, wherein the magnetic recording tape has a thickness of not more than 8 .mu.m; the non-magnetic undercoating layer has a thickness of 0.5 to 2.0 .mu.m; the magnetic recording layer has a thickness of 0.5 to 1.0 .mu.m; the polymer web has a Young's modules of not lower than 700 kg/mm.sup.2 in its width direction; and the back-coating layer is made of a binder polymer, a carbon black and an inorganic material powder.

Growing community of inventors

Kanagawa, Japan

Satoru Hayakawa