Kuraray Noritake Dental Inc.

Noritake Co., Ltd.

Omron Automotive Electronics Co., Ltd.

Yoshihisa Yamada

Yoshihisa Ito

Atsushi Matsumoto

Naofumi Murata

Kiyoko Ban

Hiroshi Inada

Kei Kashiyama

Shinji Harada

Tomohiro Sakata

A zirconia sintered body may have less excess material to be removed when making a prosthesis by milling, and may provide a reduction of work time, more durability for a working tool, and a faster treatment for patients, and may undergo little deformation during firing, and provide enhanced aesthetics. A columnar zirconia sintered body may have a base and a side face, the base having a surface shape that is neither square nor rectangular but has at least one straight portion.

Zirconia sintered body

A zirconia sintered body is provided in which the strength between layers of powders is improved. A flexural strength of a test sample of the zirconia sintered body, measured pursuant to JISR1601, is not less than 1000 MPa. The test sample is formed by preparing a plurality of zirconia powders, each containing zirconia and preferably yttria as a stabilizer that suppresses phase transition of zirconia, the zirconia powders differing in a composition, layering the zirconia powders to form a zirconia composition, and sintering the zirconia composition to form a zirconia sintered body. The flexural strength is measured such that a load point is positioned at a boundary of the zirconia powders, the boundary traversing the test sample of the sintered body along a direction of load application.

Zirconia sintered body, zirconia composition, zirconia pre-sintered body and dental prosthesis

A zirconia pre-sintered body suitable for dental milling, grinding and/or cutting can provide a sintered body in which the strength between layers of powders is improved. A flexural strength of a test sample of the zirconia sintered body, measured pursuant to JISR1601, is preferably not less than 1000 or 1100 MPa.

An electronic control device controls an electronic power steering apparatus including a motor configured to assist steering of a steering wheel provided in a vehicle and a torque sensor configured to detect a steering torque applied to the steering wheel. The electronic control device includes: a torque current control unit that sets a first current command value to be supplied to the motor according to a value of the steering torque applied to the steering wheel; a differential control unit that calculates a torque differential value as a differential value of the steering torque and sets a second current command value according to the torque differential value and a rotation speed of the motor; and a command value calculation unit that calculates a motor current command value to be supplied to the motor based on the first current command value and the second current command value.

Electronic control device, control method, and non-transitory computer readable medium

A workpiece unit containing a workpiece body is provided. A method for producing the workpiece unit is also provided. The workpiece body contains a plurality of sections. The sections divide the processing surface of the workpiece body. The size of each section of the workpiece body can be adjusted or selected according to the demand so that it is possible to increase utilization efficiency of the workpiece body.

Workpiece unit and method for producing same

A zirconia sintered body is provided in which the strength between layers of powders is improved. A flexural strength of a test sample of the zirconia sintered body, measured pursuant to JISR1601, is not less than 1100 MPa. The test sample is formed by preparing a plurality of zirconia powders, each containing zirconia and a stabilizer that suppresses phase transition of zirconia, the zirconia powders differing in a composition, layering the zirconia powders to form a zirconia composition, and sintering the zirconia composition to form a zirconia sintered body. The flexural strength is measured such that a load point is positioned at a boundary of the zirconia powders, the boundary traversing the test sample of the sintered body along a direction of load application.

A zirconia sintered body having gradation is provided. A method for preparing a zirconia composition comprises preparing a plurality of powders for lamination; the lamination powders containing zirconia, a stabilizer(s) suppressing phase transition of zirconia and a pigment(s) at respective different pigment content ratios, and laminating the lamination powders in a mold. In the laminating step, the mold is vibrated after at least two lamination powders are charged into the mold.

Zirconia sintered body, zirconia composition, zirconia pre-sintered body and preparing method thereof, and dental prosthesis

A method for preparing a zirconia composition comprises preparing a plurality of powders for lamination; the lamination powders containing zirconia, a stabilizer(s) suppressing phase transition of zirconia and a pigment(s) at respective different pigment content ratios, and laminating the lamination powders in a mold. In the laminating step, the mold is vibrated after at least two lamination powders are charged into the mold.

A zirconia sintered body, where when cross-sectional area of each zirconia crystal-grain is calculated in image of cross section of zirconia sintered body, converted crystal-grain size of each zirconia crystal-grain is calculated based on cross-sectional area where each zirconia crystal-grain has circular cross-sectional shape, zirconia crystal-grains are classified into class of &#x3c;0.4 &#x3bc;m, class of &#x2267;0.4 and &#x3c;0.76 &#x3bc;m, and class of &#x2267;0.76 &#x3bc;m based on converted crystal-grain size, total cross-sectional area of zirconia crystal-grains is calculated in each of classes, and rate of cross-sectional area to total cross-sectional area of all zirconia crystal-grains whose cross-sectional area has been calculated is calculated in each class, rate of cross-sectional area of zirconia crystal-grains in class of &#x3c;0.4 &#x3bc;m is 4% to 35%, rate of cross-sectional area of zirconia crystal-grains in class of &#x2267;0.4 and &#x3c;0.76 &#x3bc;m is 24% to 57%, and rate of cross-sectional area of zirconia crystal-grains in class of &#x2267;0.76 &#x3bc;m-is 16% to 62%.

Zirconia sintered body, and zirconia composition and calcined body

Zirconia sintered body having similar appearance to natural tooth. On straight line extending in first direction from one end to the other end of zirconia sintered body, when chromaticity (L*, a*, b*) by a L*a*b* colorimetric system of first point positioned in section from the one end to 25% of the whole length is (L1, a1, b1) and chromaticity (L*, a*, b*) by L*a*b* colorimetric system of second point positioned in section from the other end to 25% of whole length is (L2, a2, b2), L1 ranges from 58.0 to 76.0, a1 ranges from &#x2212;1.6 to 7.6, b1 ranges from 5.5 to 26.3, L2 ranges from 71.8 to 84.2, a2 ranges from &#x2212;2.1 to 1.8, b2 ranges from 1.9 to 16.0, L1&#x3c;L2, a1&#x3e;a2, b1&#x3e;b2, and tendency to increase or decrease chromaticity by the L*a*b* colorimetric system from first point to second point does not change.

Zirconia sintered body, zirconia composition and zirconia calcined body, and dental prosthesis

Provided is a high-strength zirconia sintered body in which the progression of low-temperature degradation is inhibited. The zirconia sintered body contains partially-stabilized zirconia as a matrix phase and contains at least one element from among phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi). The content of the abovementioned element(s) in the zirconia sintered body ranges from 4&#xd7;10mol to 4&#xd7;10mol with respect to 1 mol of zirconium(IV) oxide. Preferably, the zirconia sintered body further contains 0.03% to 3% by mass of silicon dioxide.

Zirconia sintered body, and mixture, pre-sintered compact and pre-sintered calcined body for sintering zirconia sintered body

It is provided a fluorescent zirconia material including a fluorescent component and emitting fluorescence when excited with a light of a predetermined wavelength, the fluorescent component including a fluorescent material, the fluorescent material including at least one kind of YSiO:Ce, YSiO:Tb, (Y, Gd, Eu)BO, YO:Eu, YAG:Ce, ZnGaO:Zn and BaMgAlO:Eu and the fluorescent material being capable of emiting the fluorescence when subjected to firing treatment at temperatures ranging from 1300 to 1600(&#xb0; C.) under oxidizing environments.

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Miyoshi, Japan

Yoshihisa Yamada