A method that enables fabrication of a machinable zirconia composite sintered body that is machinable in a sintered state while maintaining properties suited for dental use, in a shorter time than it is possible with conventional methods. A method for producing a machinable zirconia composite sintered body by fabricating a molded body with a raw material composition that includes 78 to 95 mol % of ZrO.sub.2 and 2.5 to 10 mol % of Y.sub.2O.sub.3, and also includes 2 to 8 mol % of Nb.sub.2O.sub.5 and/or 3 to 10 mol % of Ta.sub.2O.sub.5, and in which ZrO.sub.2 predominantly includes a monoclinic crystal system and sintering the molded body.

A method that enables fabrication of a machinable zirconia composite sintered body that is machinable in a sintered state while maintaining properties suited for dental use, in a shorter time than it is possible with conventional methods. A method for producing a machinable zirconia composite sintered body by fabricating a molded body with a raw material composition that includes 78 to 95 mol % of ZrO.sub.2 and 2.5 to 10 mol % of Y.sub.2O.sub.3, and also includes 2 to 8 mol % of Nb.sub.2O.sub.5 and/or 3 to 10 mol % of Ta.sub.2O.sub.5, and in which ZrO.sub.2 predominantly includes a monoclinic crystal system and sintering the molded body.

The invention relates to a process for the preparation of a dental restoration, in which an oxide ceramic material is (a) subjected to at least one heat treatment, and (b) cooled, wherein the cooling comprises (b1) a first cooling step with the cooling rate T1 and (b2) a second cooling step with the cooling rate T2 and wherein the absolute value of the cooling rate T2 is less than the absolute value of the cooling rate T1.

A manufacturing system includes a tape advancing through the manufacturing system and a station of the manufacturing system. The tape includes a first portion having grains of an inorganic material bound by an organic binder. The station of the manufacturing system receives the first portion of the tape and prepares the tape for sintering by chemically changing the organic binder and/or removing the organic binder from the first portion of the tape, leaving the grains of the inorganic material, to form a second portion of the tape and, at least in part, prepare the tape for sintering.

A manufacturing system includes a tape advancing through the manufacturing system and a station of the manufacturing system. The tape includes a first portion having grains of an inorganic material bound by an organic binder. The station of the manufacturing system receives the first portion of the tape and prepares the tape for sintering by chemically changing the organic binder and/or removing the organic binder from the first portion of the tape, leaving the grains of the inorganic material, to form a second portion of the tape and, at least in part, prepare the tape for sintering.

Coated zirconia fine particle containing a zirconia fine particle and a coating layer coating the surface of the fine particle. The coating layer includes one or more metal elements selected from Mg, Ca, Al and rare-earth elements, and the coated zirconia fine particle has an average particle size of 3 to 100 nm and a specific surface area of 20 to 500 m.sup.2/g.

Coated zirconia fine particle containing a zirconia fine particle and a coating layer coating the surface of the fine particle. The coating layer includes one or more metal elements selected from Mg, Ca, Al and rare-earth elements, and the coated zirconia fine particle has an average particle size of 3 to 100 nm and a specific surface area of 20 to 500 m.sup.2/g.

Setter plates are fabricated from Li-stuffed garnet materials having the same, or substantially similar, compositions as a garnet Li-stuffed solid electrolyte. The Li-stuffed garnet setter plates, set forth herein, reduce the evaporation of Li during a sintering treatment step and/or reduce the loss of Li caused by diffusion out of the sintering electrolyte. Li-stuffed garnet setter plates, set forth herein, maintain compositional control over the solid electrolyte during sintering when, upon heating, lithium is prone to diffuse out of the solid electrolyte.

Setter plates are fabricated from Li-stuffed garnet materials having the same, or substantially similar, compositions as a garnet Li-stuffed solid electrolyte. The Li-stuffed garnet setter plates, set forth herein, reduce the evaporation of Li during a sintering treatment step and/or reduce the loss of Li caused by diffusion out of the sintering electrolyte. Li-stuffed garnet setter plates, set forth herein, maintain compositional control over the solid electrolyte during sintering when, upon heating, lithium is prone to diffuse out of the solid electrolyte.

There are provided zirconia composition, zirconia semi-sintered body and zirconia sintered body, and dental product in which defect-generation is suppressed and transparency varies. The zirconia sintered body contains 4 mol % to 7 mol % of yttria as stabilizer. The zirconia sintered body contains shielding material. The zirconia sintered body comprises first region and second region having a higher content ratio of the shielding material than the first region. Difference between content ratio of yttria in the first region and that of yttria in the second region is 1 mol % or less.