Fuji Photo Film Company, Limited

Fujifilm Corporation

Kazuaki Taga

Hiroo Inaba

Masatoshi Takahashi

Hiroshi Ogawa

Yoshihisa Usami

Hideaki Shiga

Makoto Sato

Yutaka Senda

Satoshi Aramaki

Takayoshi Ose

Kazuo Mukouhara

Shinji Saito

Yasuo Nishikawa

Naoyoshi Chino

Yosuke Sumiya

Toshio Ishida

Kimiko Tachikawa

Toshihiko Miura

Takeshi Tsuda

Akira Ushimaru

Keiji Mori

Sunhee Lee

Shoichi Aoki

Masanori Kurihara

Insertion and removal of an index, which is interposed between a disk tray and a case half in which the disk tray is fitted, is facilitated in a disk housing case. The disk housing case is constituted by a disk tray and a first and a second case half for housing the disk tray. The index is interposed between the disk tray and the second case half. An index opening is provided at an end at which the case halves are linked, or at an end opposite the linked end. Contact openings, for enabling a finger or an index sliding member to contact the index to insert and remove the index, are provided in at least one of the disk tray and the second case half.

Disk housing case with index and contact opening therefor

A magnetic recording medium comprising a card-type disk drive and a magnetic disk cartridge. The disk drive has a length of 38 to 55 mm, a width of 35 to 51 mm, and a thickness of 3 to 5 mm, and comprises a drive mechanism for rotating the magnetic disk of the magnetic disk cartridge loaded in the disk drive, a magnetic head for magnetically recording or reproducing information on or from the magnetic disk, and an electric connection portion for electrically connecting the drive mechanism and the magnetic head with an electronic circuit provided in electronic equipment. The magnetic disk cartridge has a length of 25 to 36 mm, a width of 25 to 36 mm, and a thickness of 1 to 3 mm. The magnetic disk comprises a magnetic recording medium of high-recording density employing barium ferrite powder and has a recording capacity of 200 megabytes or larger.

Magnetic recording medium having a disk drive and cartridge

An optical data storage medium comprises a substrate having thereon concavities and convexities so that diffraction of reflected light is caused; a reflective layer having a high regular reflectance; and a colored region which is provided by applying transparent coloring ink to the reflective layer so that the regular reflectance of the reflective layer on the side opposite to the substrate side falls within a range of from 3 to 80%. The external appearance of the optical data storage medium provides a visual effect utilizing metallic gloss and light-diffraction-based iridescent reflection characteristics which result from the reflective layer provided on the substrate having concavities and convexities.

Optical recording medium having transparent color ink formed on the reflective layer

An optical information recording medium. A light reflecting layer is provided on a transparent substrate which is provided with a recording portion on which information which can be played-back by laser light is recorded. A stabilization layer is formed from a material of a density of 1.4 to 4.2 g/cm , and is provided such that a center of gravity of the optical information recording medium is included within a range of 15% of a radius r of the optical information recording medium from a center C of the optical information recording medium.

Optical information recording medium

An MD cartridge storage case is constituted by a storage case body and a cover openably/closably provided on the storage case body . An index sheet inserted into the storage case body with the cover opened is brought into contact with a stepped portion provided at the front edge of a bottom wall portion of the storage case body so that index sheet is disposed in a predetermined position. The index sheet is fixedly held when the cover of the storage case body is closed. Therefore, it is possible to provide a superior disk cartridge storage case in which not only an index sheet can be easily disposed in the storage case, but also the index sheet can be prevented from easily coming off therefrom.

Disk cartridge storage case and index card

The outer surface of an article is covered with a wrapping film, and both edges of the film are lap-welded with each other to constitute a body seal section. Both of the upper and lower edges of the film overlap extending out of an article to be wrapped are folded to the inside of the article, whereby upper and lower folded parts are formed. These folded parts overlap with each other, and are bonded and lap-welded together, thereby constituting a side seal section. An unbonded part is formed along the periphery of the upper folded part, wherein the upper folded part and the lower folded part are not bonded together. Two slits are formed in that unbonded part substantially at right angles or an inclined angle to the edge of the upper folded part, and spaced apart from each other by a certain interval. When an interval between the slits is peeled off with a finger, the unbonded part splits along the slits, and hence the side seal section splits. The split made by the slits is extended along the body seal section by pulling the split further toward the inside of the article, whereby the body seal section is removed.

Wrapped article

An MD cartridge storage case 1 is constituted by a storage case body 3 and a cover 15 openably/closably provided on the storage case body 3. An index sheet 40 inserted into the storage case body 3 with the cover 15 opened is brought into contact with a stepped portion 4b provided at the front edge of a bottom wall portion 4 of the storage case body 3 so that index sheet 40 is disposed in a predetermined position. The index sheet 40 is fixedly held when the cover 15 of the storage case body 3 is closed. Therefore, it is possible to provide a superior disk cartridge storage case in which not only an index sheet can be easily disposed in the storage case, but also the index sheet can be prevented from easily coming off therefrom.

A wrapping film having a barrel seal portion made up of both end portions of the wrapping film which are overlapped with each other and sealingly welded together, and a slit for unwrapping the film along the barrel seal portion. The slit is formed across the barrel seal portion, whereby, in unwrapping it, the wrapping film is widely torn to expose the wrapped article with ease.

Wrapping film for a wrapped article

A magnetic recording medium excellent in electromagnetic properties is disclosed, which comprises a non-magnetic support and at least two magnetic layers formed thereon, each of which is mainly composed of a magnetic substance and a binder, in which a first magnetic layer (a lower layer) has a coercive force of 450 to 660 Oe, a residual magnetic flux density (Br) of 1,950 gausses or more and a thickness of 1.5 to 5 .mu.m, a second magnetic layer (an upper layer) has a coercive force of 700 to 900 Oe, a residual magnetic flux density of 1,500 gausses or more and a thickness of 1.5 to 3 .mu.m, the difference in coercive force between the first magnetic layer and the second magnetic layer is 150 to less than 300 Oe, the difference in residual magnetic flux density between the first magnetic layer and the second magnetic layer is within 600 gausses, and the total thickness of magnetic layers on the non-magnetic support is 3 to 7 .mu.m.

Magnetic recording medium

A magnetic recording medium comprising a nonmagnetic support and at least two magnetic layers on the support, each magnetic layer containing a ferromagnetic powder and a binder, wherein the lower magnetic layer comprises at least one layer containing a branched fatty acid-modified silicone, but not carbon black, and the upper magnetic layer comprises at least one layer containing a branched fatty acid-modified silicone and carbon black having a DBP absorption oil amount of 100 to 250 ml/100 g. The magnetic recording medium has improved lubricating characteristics.

Magnetic recording medium comprising two magnetic layers each layer

A magnetic recording medium is provided comprising a non-magnetic support having thereon at least one magnetic layer comprising a ferromagnetic powder, a binder, and at least one of organic silicone compounds represented by formulae (I-1) or (I-2); ##STR1## wherein R represents a branched saturated hydrocarbon group having from 7 to 24 carbon atoms; m represents an integer of from 1 to 100; n represents an integer of from 0 to 250; and m.gtoreq.n/5.

Magnetic recording medium having a magnetic layer comprising

A magnetic recording comprising a non-magnetic support having thereon first and second magnetic layers containing a binder and a ferromagnetic powder. In a first embodiment, the content of the binder in each magnetic layer containing a vinyl chloride resin or a cellulose resin is characterized in relation to the quantity of the ferromagnetic powder contained therein. In a second embodiment, each of the magnetic layers is characterized in terms of a difference in glass transition point of a polyurethane resin contained therein. In a third embodiment, each of the magnetic layers is characterized in terms of thickness and polyisocyanate content, wherein the content of the polyisocyanate in the first magnetic layer is at least one part by weight larger than the amount of the polyisocyanate in the second magnetic layer.

A magnetic recording medium comprising a non-magnetic support having at least two magnetic layers formed thereon, the at least two magnetic layers being formed by providing, in sequence, a first magnetic layer containing first ferromagnetic powder and a first binder on a surface of the non-magnetic support and then providing a second magnetic layer containing a second binder and second ferromagnetic powder while the first layer is in a wet state, the first magnetic layer containing the first binder in an amount of 10 to 27 parts by weight based on 100 parts by weight of the first ferromagnetic powder, the second magnetic layer containing the second binder in an amount of 14 to 30 parts by weight based on 100 parts by weight of the second ferromagnetic powder, the amount of the first binder contained in the first magnetic layer being smaller than that of the second binder contained in the second magnetic layer with a difference therebetween being from 0.5 to 10 parts by weight, and a ratio (A/B) of a dry thickness (A) of the first magnetic layer to a dry thickness (B) of the second magnetic layer being from 0.5 to 3.2. The magnetic recording medium is excellent in electromagnetic conversion characteristics and running stability.

A magnetic recording medium comprising a non-magnetic support having thereon a plurality of magnetic layers each comprising a ferromagnetic powder dispersed in a binder, wherein the layer located within a thickness of 0.5 .mu.m from an uppermost surface of said plurality of magnetic layers and a layer located within a thickness of 0.5 .mu.m above the adjacent non-magnetic support have a higher packing density of ferromagnetic powder than an interlayer interposed therebetween. In a preferred embodiment, the interlayer consists of two layers and there are provided on the non-magnetic support a 1st magnetic layer, a 2nd magnetic layer, a 3rd magnetic layer and a 4th magnetic layer in this order from the non-magnetic support; the sum of the thickness of said 3rd magnetic layer and said 4th magnetic layer being not more than 3.5 .mu.m.

A magnetic recording medium which comprises plurality of magnetic layers comprising at least first and second magnetic layers which are successively formed on a surface of a polyethylene terephthalate support, wherein said support contains inert inorganic particles having an average particle size of from 0.5 to 0.7 microns, a standard deviation of 0.1 microns or less and the surface of said support has a center line average roughness (Ra) of 16 nm or less and a density of protrusions (Ds) of 6000/mm.sup.2 or more in the case of protrusions of 0.7 microns of more.

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Tokyo, Japan

Kazuaki Taga