Tdk Corporation

Tdk Electronics Company, Limited

Yasumichi Tokuoka

Kenji Yokoyama

Keiji Koga

Shinji Umeki

Jiro Yoshinari

Yuichi Kubota

Kazumasa Fukuda

Jun-ichi Satoh

Akinori Nisizawa

Akio Watanabe

Shigeki Satou

Yoshisuke Yamakawa

Kazuhide Aue

Minoru Yoda

Shigeki Sato

Takeshi Nomura

Akira Yamaguchi

Masatoshi Nakayama

Haruyuki Morita

Hitoshi Arai

Sunao Masuda

Akihiko Hosaka

Katsuhiko Igarashi

Toshiaki Izumi

Takayoshi Kobuke

Tsuneo Kagotani

Tomoko Uchida

Tatsunori Satou

Hideki Hotsuki

Norio Higuchi

A production method of an electronic device comprising the steps of forming a stacked body by stacking green sheets and electrode layers having a predetermined pattern and firing the stacked body. Before forming the stacked body, a blank pattern layer is formed on a space portion of the electrode layer having a predetermined pattern. The electrode level difference absorbing print paste for forming the blank pattern layer includes at least ceramic powder and a binder resin, and a polymerization degree of the binder resin is made equal to or more than that of a binder resin included in slurry for forming the green sheet. The binder resin of the electrode level difference absorbing print paste includes polyvinyl butyral resin with a polymerization degree of 1400 or more, a butyralation degree of 64 to 74 mol % and an acetalization degree of 66 to 74 mol %.

Electrode level difference absorbing print paste and method of producing electronic device

A production method of a multilayer ceramic device is provided, by which, for example, a multilayer ceramic capacitor having a large capacity, wherein the interlayer thickness is made as thin as about 2.5 &#x3bc;m or thinner, can be produced at a high production yield without causing unsticking between layers and internal defects. In the present invention, when assuming that a first weight ratio (wt %) of the first organic binder component with respect to a first inorganic dielectric colorant powder in said green sheet slurry for forming a green sheetis (A), and a second weight ratio (wt %) of the second organic binder component with respect to said second inorganic dielectric colorant powder in said electrode level difference absorbing dielectric paste for forming a dielectric blank pattern layeris (B), the second weight ratio (B) is larger than the first weight ratio (A).

Multilayer ceramic device and the production method thereof

Internal electrode layers of a multilayer ceramic electronic element are structured such that spaces, which are formed between adjacent internal electrodes, are eliminated so as to substantially flatten the internal electrode layers. Moreover, the thickness of each green dielectric layer is reduced. To achieve this, a laminating process is performed by a thermal transfer printing method such that a thermal transfer conductor material and a thermal transfer dielectric material are used so as to form internal electrode portions and green dielectric portions. Thus, the internal electrode layers are formed.

Multilayer ceramic electronic element and manufacturing method therefor

The invention provides an electronic device comprising a first metal layer containing a first metal converted into an oxide upon firing in an oxidizing atmosphere and a second metal layer formed by firing of a second metal particle containing a metal that is not oxidized upon firing in an oxidizing atmosphere, with an intermediate oxide layer interleaved between these two metal layers. The intermediate oxide layer contains an oxide of the first metal contained in the first metal layer. Preferably, the second metal particle contained in the second metal layer is dispersed in the intermediate oxide layer. A uniform oxide layer is obtained at a simple step, and the resistance value provided by the oxide layer is easily controllable with high precision. It is thus possible to achieve an electronic device in which the bonding strength of the oxide layer with respect to the other metal-containing layer is improved with an improvement in the bonding strength with respect to lead wires.

Electronic device, and its fabrication method

A magnetic recording medium includes a coated type of magnetic layer containing magnetic powders substantially made up of hexagonal ferrite particles and a binder, and has the values of

Magnetic recording medium comprising two magnetic layers of hexagonal

Ultrafine particles of Fe-Co-P material with a Fe/Co atomic ratio of from 95/5 to 70/30 and a (Fe+Co)/P atomic ratio of from 85/15 to 60/40 show improved ferromagnetic properties. The average particle size is from 0.005 to 0.1 .mu.m. Such ultrafine particles are prepared through gas phase reaction by evaporating a source material. They are useful in both magnetic and thermomagnetic recording media ensuring high density recording.

Ferromagnetic stabilized ultrafine spherical hexagonal crystalline Fe.sub.2

Ultrafine particles of Fe--Co--P material with a Fe/Co atomic ratio of from 95/5 to 70/30 and a (Fe+Co)/P atomic ratio of from 85/15 to 60/40 show improved ferromagnetic properties. The average particle size is from 0.005 to 0.1 .mu.m. Such ultrafine particles are prepared through gas phase reaction by evaporating a source material. They are useful in both magnetic and thermomagnetic recording media ensuring high density recording.

Ferromagnetic ultrafine particles, method of making, and recording

Method of making ferromagnetic ultrafine particles

A magnetic disk suitable for high density recording and reproduction of information wherein said disk is a coating type disk comprising a rigid substrate having a magnetic layer coated thereon from a magnetic coating composition of ferromagnetic submicron particles in a binder, wherein the substrate has a surface roughness Ra of up to 0.007 .mu.m, the magnetic layer has a thickness of up to 0.5 .mu.m, a surface roughness Ra of up to 0.005 .mu.m, and a porosity of 4 to 45%.

Magnetic disk

Information is magnetically recorded in and reproduced from a magnetic disk using a flying magnetic head. The disk is a coating type disk comprising a rigid substrate having a magnetic layer coated thereont from a magnetic coating composition of ferromagnetic submicron particles in a binder. High density recording is possible when the substrate has a surface roughness Ra of up to 0.007 .mu.m, the magnetic layer has a thickness of up to 0.5 .mu.m, a surface roughness Ra of up to 0.005 .mu.m, and a porosity of 4 to 45%.

Method for making a magnetic disk

Information is magnetically recorded in and reproduced from a magnetic disk using a flying magnetic head. The disk is a coating type disk comprising a rigid substrate having a magnetic layer coated thereon from a magnetic coating composition of ferromagnetic submicron particles in a binder. High density recording is possible when the magnetic layer having a coercive force of at least 1100 Oe and a thickness of up to 0.5 .mu.m is combined with the flying magnetic head whose gap adjoining portion is made of a soft magnetic material having a saturation magnetic flux density of at least 0.7 T.

Magnetic recording and reproduction

A magnetic recording medium having a magnetic coating containing therein ferromagnetic metal powder provided on a base film, wherein the magnetic recording medium being characterized in that the surface roughness of the magnetic coating, i.e., the surface roughness R.sub.rms (a unit of measurement of .mu.m) with respect to a waveform having a wavelength P in a range of from 3 to 50 .mu.m out of groups of waveforms constituting the cross-sectional waveform of the surface of the magnetic coating, satisfies the following equation.

Method of making a magnetic recording medium

In a magnetic recording medium comprising a base and a magnetic coating layer formed thereon which consists of ferromagnetic particles dispersed in a binder, the magnetic layer contains from 3 to 15 percent by weight, on the basis of the magnetic powder weight, of abrasive particles having a Mohs hardness of 6 or upward, in such a manner that the average number of the abrasive particles per unit area of the magnetic layer surface is at least 0.25 per square micron. The magnetic powder is a magnetic metal powder based on iron, and the abrasive particles are angular rather than granular in shape.

Magnetic recording medium

A magnetic recording medium having a magnetic coating containing therein ferromagnetic metal powder provided on a base film, wherein the magnetic recording medium being characterized in that the surface roughness of the magnetic coating, i.e., the surface roughness R.sub.rms (a unit of measurement of .mu.m) with respect to a waveform having a wavelength P in a range of from 3 to 50 .mu.m out of groups of waveforms constituting the cross-sectional waveform of the surface of the magentic coating, satisfies the following equation:

A magnetic recording medium is coated, over its magnetic layer, with a thin film of a siloxane-linkage-containing polymer. The magnetic layer consists of a thin film formed by vacuum evaporation or sputtering or by dispersion of a ferromagnetic metal powder in a binder. The polymer having the siloxane linkage is prepared by polymerizing an organo-silicon compound which either inherently possesses the linkage or is capable of producing it. The polymerization is preferably effected by the plasma polymerization technique.

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Saku, Japan

Yasumichi Tokuoka