Hitachi Maxell, Limited

Fujifilm Corporation

Maxell Holdings, Ltd.

Sadamu Kuse

Kenji Tanaka

Masao Fujita

Seigi Kawarai

Tsugihiro Doi

Tetsutaro Inoue

Shinji Kawakami

Hiroyuki Mitsuhashi

Mikio Kishimoto

Masao Okafuji

Toshio Kawakita

Kenichiro Yoshida

Yuji Sasaki

Hideaki Watanabe

Kazuhiko Nakiri

Shihoko Takashima

Yukihiro Hata

Hideyuki Tanaka

Hiroyuki Ota

Katsuyuki Kito

Yasuo Inugai

Shinji Tsujimoto

Noriaki Otani

Kimihiko Kaneno

Hisanobu Mikamo

Junichi Hirata

Shigeo Fujitani

Yoshiaki Kudo

Junichi Sato

Yoshiro Nishimura

Shigeru Yasuda

Manabu Nose

Yasushi Orita

Hisashi Takai

Junichiro Saikai

Hidekazu Kawatoko

Tomoki Inakura

Makoto Shiokawa

Masanori Yamasaki

Hitoshi Tsukamoto

Motoya Miura

The magnetic recording medium includes a non-magnetic substrate, a non-magnetic layer, and a magnetic layer, wherein the magnetic layer contains a hexagonal strontium ferrite magnetic powder, Mr and t satisfy 0.0020 &#x3bc;T&#xb7;m&#x2264;Mr&#xb7;t&#x2264;0.0150 &#x3bc;T&#xb7;m, where Mr is the residual magnetic flux density of the magnetic layer, and t is the average thickness of the magnetic layer, Lsatisfies 2 nm&#x2264;L&#x2264;6 nm, where Lis the average thickness of a first mixed layer that is formed on the surface of the magnetic layer opposite to the non-magnetic layer, Lsatisfies 0.1&#x2264;L/t&#x2264;0.45, where Lis the average thickness of a second mixed layer that is formed on the surface of the magnetic layer facing the non-magnetic layer.

Magnetic recording medium

A magnetic recording medium of the present invention is a magnetic recording medium including a non-magnetic substrate; a non-magnetic layer that is formed on one of principal surfaces of the non-magnetic substrate and contains a non-magnetic powder, a binder, and a lubricant; and a magnetic layer that is formed on a principal surface of the non-magnetic layer opposite to the non-magnetic substrate and contains a magnetic powder and a binder. The magnetic powder has an average particle size between 10 nm and 35 nm inclusive. The lubricant is migratable to the magnetic layer and forms a lubricant layer on a surface of the magnetic layer when a pressure is applied to the magnetic layer. When spacing of the surface of the magnetic layer before and after washing the lubricant with n-hexane is measured with a TSA (Tape Spacing Analyzer), the value of the spacing after washing is 3 to 10 nm, and the value of the spacing before washing is 1 to 5 nm smaller than the value of the spacing after washing.

Disclosed is an ink composition for clear layer formation having excellent adhesion properties on substrates, recording layers, and clear layers, as well as excellent overcoat characteristics and refinishing properties. Further disclosed are a coating method for the ink composition, and a printed article formed using the ink composition. The ink composition for clear layer formation is used for forming at least one clear layer on a substrate, or on a printed article on which a printed coating film is formed on a substrate as a recording layer. The ink composition for clear layer formation is characterised in that: the surface free energy of the substrate is 30-45 (mJ/m); the surface free energy of the recording layer is 40-50 (mJ/m); the contact angle of the ink composition to the substrate is 30-65 degrees, the contact angle of the ink composition to the recording layer is 40-55 degrees, and the contact angle of the ink composition to the clear layer is 45-60 degrees.

Ink composition for forming clear layer, method of applying the same, and printed article using the same

The magnetic recording medium of the present invention comprises: a non-magnetic substrate; a non-magnetic layer formed on one of principal surfaces of the non-magnetic substrate; and a magnetic layer formed on a principal surface of the non-magnetic layer opposite to the non-magnetic substrate. Mr and t satisfy 0.0020 &#x3bc;T&#xb7;m&#x2266;Mr&#xb7;t&#x2266;0.0150 &#x3bc;T&#xb7;m, where Mr is the residual magnetic flux density of the magnetic layer, and t is the average thickness of the magnetic layer, Lsatisfies 2 nm&#x2266;L&#x2266;6 nm, where Lis the average thickness of a first mixed layer that is formed on the surface of the magnetic layer opposite to the non-magnetic layer, and Lsatisfies 0.1&#x2266;L/t&#x2266;0.45, where Lis the average thickness of a second mixed layer that is formed on the surface of the magnetic layer facing the non-magnetic layer.

A method for manufacturing a magnetic recording medium of the present invention includes a magnetic layer forming step in which a drying process is performed. The drying process includes: a pre-heating stage in which a magnetic coating film is heated until the surface temperature of the magnetic coating film stops rising and reaches a substantially constant temperature; a constant rate drying stage that is performed after the pre-heating stage in which the surface temperature of the magnetic coating film is held substantially constant; and a falling rate drying stage that is performed after the constant rate drying stage in which the surface temperature of the magnetic coating film is increased to be higher than the surface temperature during the constant rate drying stage to harden the magnetic coating film. The constant rate drying period in which the constant rate drying stage is performed is 0.2 seconds or more. The first solvent is made of one solvent or two or more solvents having different boiling points, and the difference (T&#x2212;T) between the boiling point Tof the solvent having the lowest boiling point among the solvents contained in the first solvent and the surface temperature Tof the magnetic coating film during the constant rate drying period is 1 to 50&#xb0; C.

Magnetic recording medium and method for manufacturing the same

A magnetic tape driving apparatus, which does not cause damage to either a magnetic head or a magnetic tape when making transition of the magnetic tape from a stopped state to a running state, when making transition of the magnetic tape from a running state to a stopped state, or when reversing the transportation direction of the magnetic tape, is provided. In a state where any one of a magnetic head and a magnetic tape moves and the other rests (i.e., a state where static friction may occur), such as at the time of starting transportation of the magnetic tape, at the time of stopping the tape in a running state, and at the time of reversing the transportation direction of the magnetic tape, a head displacing portion vibrates the magnetic head under the control by a displacement control portion, and thus no static friction occurs between the magnetic head and the magnetic tape. Therefore, the risk of causing damage to the magnetic head (such as an MR head unit equipped with an MR element) or the magnetic tape can be reduced.

Magnetic tape driving apparatus having a head displacing portion

The present invention provides a magnetic head that can sustain favorable head contact even when magnetic tapes having different thicknesses are used. A magnetic head has a sliding surface coming in contact with a moving magnetic tape. An electromagnetic transducing element is disposed in the sliding surface. First edges are formed at each end of the sliding surface in the direction of movement of the magnetic tape. Second edges are formed in positions extended in the direction of movement of the magnetic tape from each end of the sliding surface and come in contact with the magnetic tape.

Magnetic tape head with limited ranges of tape wrap angle and distance between first and second edges

A cleaning structure for removing dust is constituted of a guiding member having a sliding surface for guiding run of a tape, and a vacuum pressure supply source for making a vacuum pressure effect on a suction space provided inside the guiding member and so on. At the sliding surface of the guiding member, a suction port for making the suction space communicate with an external space is formed, and the opening edge of the suction port on the downstream side in the tape running direction is served as a first dust removal portion for removing dust on the tape surface. The guiding member has a guiding wall having a contact surface which guides at least one tape edge of a tape, and the contact surface is served as a second dust removal portion for removing dust adhering to the tape edge.

Tape device having a tape cleaning structure

A magnetic tape apparatus includes a feeding unit for feeding a magnetic tape; a take-up unit for taking up the magnetic tape, a magnetic head disposed the downstream of the feeding unit and the upstream of the winding unit, in a traveling path of the magnetic tape from the feeding unit to the take-up unit, and having the moving magnetic tape abut to the magnetic head; a fixed guide unit disposed adjacent to the magnetic head at least in the upstream on downstream of the traveling direction of the magnetic tape traveling on the traveling path toward the magnetic head and guiding the magnetic tape to the traveling path by abutting to the magnetic tape; and a controlling unit disposed on the fixed guide unit for controlling the movement of the magnetic tape in the tape width direction. On a contact surface which abuts on the magnetic tape in the fixed guide unit, there is provided a space for excluding the air lying between the moving magnetic tape and the contact surface.

Magnetic tape apparatus

A magnetic tape driving apparatus of the present invention includes a support member for separating a magnetic tape from a magnetic head on at least one of a tape input side and a tape output side of the magnetic head. The support member separates the magnetic tape from the magnetic head at least when a tape driving portion causes the magnetic tape to start running and/or to stop running. With this configuration, the magnetic tape driving apparatus does not suffer from damage to the magnetic head and the magnetic tape when the magnetic tape makes a transition from the stopped state to the running state and vice versa or changes in the running direction.

Magnetic tape driving apparatus comprising a tape separation portion that separates a magnetic tape from a magnetoresistive head unit

A data recording apparatus of the present invention includes a head that records data signals by magnetizing a magnetic tapeand a recording control portion that controls the recording operation by causing recording current to flow to the head. The recording control portion controls the operation of the head, so that in the magnetic tape, which is direct current demagnetized continuously in the longitudinal direction, a magnetic field is formed intermittently in an opposite direction to the magnetization direction of the direct current demagnetization. Thus, when recording data signals on the magnetic recording medium, it is possible to make the current flowing to the head small and to realize apparatus power consumption reductions, load reductions for the head and circuitry, and reduction in crosstalk noise from the head chip used for writing to the head chip used for reading.

Data recording apparatus and data recording method

A magnetic recording medium with excellent high density recording performances and good durability comprising a non-magnetic substrate, a non-magnetic layer containing a non-magnetic powder and a binder formed on the non-magnetic substrate, and a magnetic layer having a thickness of less than 100 nm and containing a substantially particulate non-magnetic powder, a substantially particulate magnetic powder having an average particle size of less than 25 nm, and a binder, wherein an average particle size R of the non-magnetic powder contained in the magnetic layer and a thickness D of the magnetic powder satisfy the following relationship: 0.88&#x2266;R/D&#x2266;2.5.

The present invention provides a recording and reproducing apparatus that can perform high-precision tracking servo control by removing noise from detected servo signals. The recording and reproducing apparatus performs tracking servo control while reading servo signalsthat are formed on a surfaceof a recording mediumso as to produce optical contrast, the apparatus including a modulated irradiatorfor irradiating the servo signalswith a light beam, the intensity of the light beam being modulated by a modulating wave that is frequency-modulated; a photoelectric converterfor converting reflected light from the servo signalsinto electric signals; and a synchronous demodulatorfor subjecting the electrical signal to synchronous demodulation using the modulating wave as a reference wave.

Recording and reproducing apparatus and recording medium

In the apparatus and method of the invention, a servo signal reproduction unit generates a PES from a servo signal reproduced from a magnetic tape, and a frequency conversion unit performs FFT processing of the PES to generate frequency component information. Then, a filter value generation unit generates filter values based on the frequency component information and writes these to a memory. When recording various data signals to the magnetic tape, the filter values are read from the memory and a control filter serving as a notch filter is incorporated into a feedback control for a tracking servo. This enables periodic and narrow-band noise to be removed from a PES, consequently reducing PESs. Accordingly, learning-type optimum notch filter control that allows a magnetic head to follow recording tracks at high speed and with high precision is possible even when the recording track width is reduced and the tape speed is increased.

Growing community of inventors

Osaka, Japan

Sadamu Kuse