Hideaki Niimi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
Abstract: A semiconductive ceramic having a negative temperature coefficient of resistance, includes an oxide of a rare earth transition element excluding Ce and including Y, with the addition of at least one of the following elements: Si, Zr, Hf, Ta, Sn, Sb, W, Mo, Te or Ce.
Abstract: A semiconductor ceramic device includes a semiconductor ceramic sintered body and external electrodes. The semiconductor ceramic sintered body contains a lanthanum cobalt type oxide major component, about 0.1 to 10 mol % on an element conversion basis of an oxide of Cr as a sub-component, and about 0.001 to 0.5 mol % on an element conversion basis of at least one of the oxides of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ni, Cu and Zn.
Abstract: The present invention provides barium titanate powder having a withstanding voltage of 800 V/mm or more and a specific resistance at room temperature of 100 .OMEGA..multidot.cm or less, the specific resistance at room temperature undergoing substantially no time-course change. Barium titanate of the powder of the present invention assumes a cubic crystal system. The powder has a particle size of about 0.1 .mu.m or less; the ratio represented by BaCO.sub.3 /BaO as obtained through XPS is about 0.42 or less; the lattice constant is about 0.4020 nm or more; and the ratio represented by Ba/Ti is about 0.988-0.995.
Abstract: The present invention provides a barium titanate-based semiconducting ceramic which exhibits excellent PTC characteristic and which can be fired at a temperature lower than 1000.degree. C. The present invention also provides an electronic element fabricated from the ceramic. The semiconducting ceramic contains, in a semiconducting sintered barium titanate; boron oxide; an oxide of at least one of barium, strontium, calcium, lead, yttrium and a rare earth element; and an optional oxide of at least one of titanium, tin, zirconium, niobium, tungsten and antimony in which the atomic boron is0.005.ltoreq.B/.beta..ltoreq.0.50 and1.0.ltoreq.B/(.alpha.-.beta.).ltoreq.4.0wherein .alpha. represents the total number of atoms of barium, strontium, calcium, lead, yttrium and rare earth element contained in the semiconducting ceramic, and .beta. represents the total number of atoms of titanium, tin, zirconium, niobium, tungsten and antimony contained in the semiconducting ceramic.
Abstract: A semiconductive ceramic in which the B constant is maintained at about 4000 K or more at elevated temperature to thereby decrease power consumption, and the B constant is lowered less than 4000 K at low temperature so as to avoid unnecessary increase of resistance; as well as a semiconductive ceramic element using the same. The semiconductive ceramic is formed of a lanthanum cobalt oxide, which serves as the primary component, and, as a secondary component, at least one oxide of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ni, Cu and Zn. The semiconductive ceramic element is fabricated through use of the semiconductive ceramic and an electrode formed thereon.
Abstract: A laminated composite ceramic is formed with a positive temperature coefficient (PTC) ceramic element and either a negative temperature coefficient (NTC) ceramic element or a fixed resistance ceramic element, laminated and integrated with each other as a laminated ceramic body. An inner electrode is at least on the boundary between these ceramic elements. These elements have barium titanate as main constituents. A laminated composite ceramic element has similar ceramic elements with inner electrodes buried in parts and connected to outer electrodes formed on different side surfaces of the ceramic body. The molar % of barium and titanate Ba/Ti is preferably 0.99-1.05 for the PTC ceramic element and 0.95-1.01 for the NTC and fixed resistance ceramic elements.
Abstract: A high-frequency detecting element that can detect a temperature increase in an instant due to high-frequency wave absorption using semiconducting ceramic with positive resistance-temperature characteristics. The ceramic is composed mainly of barium titanate. A high-frequency heater incorporating the high-frequency detecting element is also disclosed. In the high-frequency detecting element, electrodes are provided on one main surface of semiconducting ceramic 1 with positive resistance-temperature characteristics and leads 3a and 3b are soldered to the electrodes 2a and 2b.
Abstract: A rush current suppression circuit suppresses a peak value of a rush current flowing into a heater. The rush current suppression circuit includes a parallel circuit formed by a positive-characteristic thermistor and a negative-characteristic thermistor. The negative-characteristic thermistor has a resistance at a normal temperature higher than that of the positive-characteristics thermistor. The parallel circuit is connected in series to the heater.
Abstract: A plurality of semiconductor substrates having positive resistance-temperature coefficients are bonded to each other through a glass layer to be stacked. First and second terminal electrodes are formed on end surfaces of such a stacked structure respectively. First and second ohmic electrodes are formed on respective major surfaces of each semiconductor substrate, and the first and second ohmic electrodes are connected to the first and second terminal electrodes respectively. The ohmic electrodes contain a metal, other than silver, exhibiting an ohmic property, such as zinc, aluminum, nickel or chromium, for example. The terminal electrodes also contain a metal, other than silver, exhibiting an ohmic property. The terminal electrodes may be provided on surfaces thereof with layers which are made of a metal having excellent solderability.
Abstract: A NTC thermistor composition based on barium titanate has a Ba site and Ti site in a mole ratio (Ba site/Ti site) of 0.99 to 1.05, while 5 to 40 mole percent of the Ba site is substituted by Ca and not more than 40 mole percent is substituted by Sr.
Abstract: A semiconducting ceramic composition for secondary electron multipliers consists essentially of 55 to 80 mol % of zinc oxide, 12 to 30 mol % of titanium oxide, and 0.2 to 20 mol % of nickel oxide.
Abstract: A magnetic recording medium comprising a substrate and a ferromagnetic metal layer, wherein the ferromagnetic metal layer includes hydrated amorphous cobalt oxide, a X-ray photoelectron spectra which is characterized in that, in the Co.sub.2p spectrum, a ratio of a peak height at 785.9.+-.0.3 eV to that at 780.0.+-.0.3 eV is 40/100 or less when a background (BG) line is drawn between lower energy side leading edge points of peaks at 780.0.+-.0.3 eV (2p.sub.3/2) and 795.6.+-.0.3 eV (2p.sub.1/2) and, in the O.sub.1s spectrum, a ratio of a peak height at 529.3.+-.0.4 eV to that at 530.8.+-.0.4 eV is from 100:110 to 100:50 when a background line is drawn between the lower energy side leading edge point and the higher energy side leading edge point of a complex peak at 530.5.+-.2.5 eV from which the peaks at 529.3.+-.0.4 eV and 530.8.+-.0.4 are derived by peak synthesis, which has good corrosion and wear resistance.
Abstract: A magnetic recording medium comprising a substrate and, as a recording layer, a ferromagnetic metal thin layer formed on the substrate by deposition, in which the ferromagnetic metal thin layer contains oxygen atom in such a manner that concentrations of oxygen atom in a surface layer and an interfacial layer adjacent to the substrate are higher than that in an intermediate layer between the surface and interfacial layers, which has an improved coercive force and smaller magnetic domain.
Abstract: In a recording tape cartridge having a cartridge case, magnetic recording tape and a front lid and a rear lid for protecting the magnetic tape, there are provided entrance preventing members at a bottom the cartridge case facing to clearances between side edges of the front lid and case body for preventing entrance of harmful floating particles into the area near the recording tape so as to prevent corrosion of the recording tape.
Abstract: A magnetic recording medium comprising a substrate and, as a recording layer, a ferromagnetic metal thin layer formed on the substrate by deposition, in which the ferromagnetic metal thin layer contains oxygen atom in such a manner that concentrations of oxygen atom in a surface layer and an interfacial layer adjacent to the substrate are higher than that in an intermediate layer between the surface and interfacial layers, which has improved coercive force and smaller magnetic domain.