WO2015098765A1 - 透光性ジルコニア焼結体及びジルコニア粉末、並びにその用途 - Google Patents
透光性ジルコニア焼結体及びジルコニア粉末、並びにその用途 Download PDFInfo
- Publication number
- WO2015098765A1 WO2015098765A1 PCT/JP2014/083763 JP2014083763W WO2015098765A1 WO 2015098765 A1 WO2015098765 A1 WO 2015098765A1 JP 2014083763 W JP2014083763 W JP 2014083763W WO 2015098765 A1 WO2015098765 A1 WO 2015098765A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- zirconia
- sintered body
- powder
- mol
- zirconia sintered
- Prior art date
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C13/00—Dental prostheses; Making same
- A61C13/08—Artificial teeth; Making same
- A61C13/082—Cosmetic aspects, e.g. inlays; Determination of the colour
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C13/00—Dental prostheses; Making same
- A61C13/0003—Making bridge-work, inlays, implants or the like
- A61C13/0022—Blanks or green, unfinished dental restoration parts
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C13/00—Dental prostheses; Making same
- A61C13/08—Artificial teeth; Making same
- A61C13/083—Porcelain or ceramic teeth
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C7/00—Orthodontics, i.e. obtaining or maintaining the desired position of teeth, e.g. by straightening, evening, regulating, separating, or by correcting malocclusions
- A61C7/12—Brackets; Arch wires; Combinations thereof; Accessories therefor
- A61C7/14—Brackets; Fixing brackets to teeth
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K6/00—Preparations for dentistry
- A61K6/80—Preparations for artificial teeth, for filling teeth or for capping teeth
- A61K6/802—Preparations for artificial teeth, for filling teeth or for capping teeth comprising ceramics
- A61K6/818—Preparations for artificial teeth, for filling teeth or for capping teeth comprising ceramics comprising zirconium oxide
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G25/00—Compounds of zirconium
- C01G25/02—Oxides
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/48—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates
- C04B35/486—Fine ceramics
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/62605—Treating the starting powders individually or as mixtures
- C04B35/62695—Granulation or pelletising
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/64—Burning or sintering processes
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C2201/00—Material properties
- A61C2201/002—Material properties using colour effect, e.g. for identification purposes
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/50—Solid solutions
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/50—Solid solutions
- C01P2002/52—Solid solutions containing elements as dopants
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/76—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by a space-group or by other symmetry indications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/10—Solid density
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3224—Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
- C04B2235/3225—Yttrium oxide or oxide-forming salts thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
- C04B2235/54—Particle size related information
- C04B2235/5409—Particle size related information expressed by specific surface values
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
- C04B2235/54—Particle size related information
- C04B2235/549—Particle size related information the particle size being expressed by crystallite size or primary particle size
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/60—Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
- C04B2235/602—Making the green bodies or pre-forms by moulding
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/60—Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
- C04B2235/608—Green bodies or pre-forms with well-defined density
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
- C04B2235/6562—Heating rate
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/72—Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/74—Physical characteristics
- C04B2235/77—Density
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
- C04B2235/9646—Optical properties
- C04B2235/9653—Translucent or transparent ceramics other than alumina
Definitions
- the present invention relates to a zirconia sintered body having a high density and strength of a sintered body and a translucency very close to natural teeth.
- This highly light-transmitting zirconia sintered body is used for dental use, particularly for anterior teeth, and further suitable for use as a mill blank such as a denture material or an orthodontic bracket.
- a zirconia sintered body (hereinafter referred to as “partially stabilized zirconia sintered body”) in which a small amount of Y 2 O 3 is dissolved as a stabilizer has high strength and high toughness. Therefore, the partially stabilized zirconia sintered body is used as a material for mechanical structures such as a cutting tool, a die, a nozzle, or a bearing. In addition to mechanical structural materials, they are used as biomaterials such as dental materials. When using a partially stabilized zirconia sintered body as a dental material, not only from the viewpoint of mechanical properties such as high strength and high toughness, but also from optical aspects such as translucency and color tone are required.
- a zirconia single crystal (cubic zirconia) containing about 10 mol% of yttria has been conventionally used for jewelry as translucent zirconia.
- the zirconia single crystal has a problem that its strength is extremely low.
- a zirconia sintered body which is a polycrystal of zirconia does not have translucency. As this cause, it is known that pores existing between crystal grains and in crystal grains cause light scattering. Therefore, studies have been made so far to impart translucency to a polycrystalline zirconia sintered body by reducing pores, that is, increasing the density of the sintered body.
- Patent Document 1 discloses a zirconia sintered body containing 2 to 4 mol% of yttria, an alumina content of 0.2 wt% or less, and a 1 mm-thick total light transmittance of 35% or more.
- the sintered body disclosed in the example had a total light transmittance of 41%, which was 36% as a total light transmittance for light having a wavelength of 600 nm at a thickness of 1.0 mm.
- the sintered body was a sintered body having sufficient translucency and strength when used as a denture for a back tooth.
- the sintered body has a problem that the translucency is insufficient to be used as a denture for anterior teeth.
- Patent Document 2 discloses a zirconia sintered body containing 1.5 to 5 mol% of yttria and having a porosity of 0.6% or less.
- the sintered body is a zirconia sintered body obtained by pressure sintering using a hot isostatic press (hereinafter referred to as “HIP”), and the zirconia sintered body obtained by atmospheric pressure sintering. In the knot, sufficient translucency was not obtained.
- HIP hot isostatic press
- Patent Document 3 discloses a zirconia sintered body containing yttria exceeding 4 mol% and not more than 7 mol% and having a total light transmittance of 40% or more at a wavelength of 600 nm at a thickness of 1 mm. ing.
- the sintered body is also a zirconia sintered body obtained by pressure sintering using HIP, and sufficient translucency was not obtained in the zirconia sintered body obtained by atmospheric pressure sintering.
- Non-Patent Document 1 discloses transparent zirconia firing obtained by subjecting zirconia powder containing 3 mol% yttria and 8 mol% yttria to Spark Plasma Sintering (hereinafter referred to as “SPS”). A ligation is disclosed. However, when the zirconia sintered body disclosed in Patent Document 3 and Non-Patent Document 1 is used as a denture for anterior teeth, the transparency is too high, which is unnatural.
- a method in which a pre-sintered molded body is cut into a denture shape and then sintered.
- a compact is produced by subjecting zirconia powder to ordinary press molding, and then the compact is pre-sintered at a temperature of 700 to 1000 ° C. to produce a mill blank.
- the produced mill blank is cut into a denture shape by CAD / CAM, and then sintered.
- a mill blank having the shape of a carved denture is sintered using a process program in which the heating rate is 600 ° C./hr, the temperature is raised to the sintering temperature, and the holding time at the sintering temperature is 2 hours.
- zirconia is sintered in a short time of about 7 hours.
- the sintered compact after eliminating the above-mentioned drawbacks of the conventional method, the sintered compact has a high density and excellent translucency, and particularly has translucency and strength suitable as a denture for an anterior tooth.
- An object of the present invention is to provide a zirconia sintered body that is also used, and to provide a zirconia powder that can be produced with a simple process by atmospheric pressure sintering of the zirconia sintered body.
- the present inventors examined a zirconia sintered body suitable as an anterior denture. As a result, it has been found that a zirconia sintered body having a controlled composition and physical properties has aesthetics comparable to natural anterior teeth. Furthermore, the present inventors examined in detail the relationship between the yttria concentration and the alumina concentration in the zirconia powder, the sintered body density, and the total light transmittance of the sintered body.
- the gist of the present invention is as follows.
- [1] Light having a wavelength of 600 nm at a thickness of 1.0 mm, containing 4.0 mol% to 6.5 mol% yttria and less than 0.1 wt% alumina, having a relative density of 99.82% or more.
- a translucent zirconia sintered body characterized by having a total light transmittance of 37% to less than 40% and a bending strength of 500 MPa or more.
- [4] A method for producing a light-transmitting zirconia sintered body according to any one of [1] to [3] above, wherein 4.0 mol% to 6.5 mol% yttria and less than 0.1 wt% [1] to [1] to [3], which have a molding step of molding a zirconia powder containing alumina to obtain a molded body, and a sintering step of sintering the molded body at a sintering temperature of 1350 ° C. to 1500 ° C. under normal pressure.
- [3] The production method according to any one of [3].
- [5] The production method according to the above [4], wherein the density of the molded body is more than 3.2 g / cm 3 .
- the zirconia powder according to [6] wherein the crystallite diameter is 320 to 380 mm.
- the zirconia powder according to the above [6] or [7] which has an average particle size of 0.40 to 0.50 ⁇ m.
- a dental material comprising the translucent zirconia sintered body according to any one of [1] to [3].
- the dental material according to [13] which is a denture, a denture mill blank, an anterior denture, an anterior denture mill blank, or an orthodontic bracket.
- the zirconia sintered compact which has the translucency and intensity
- the translucent zirconia sintered body of the present invention is excellent in translucency, and can be used as a zirconia sintered body used in dental applications, in particular, in an anterior denture. Moreover, it can also be used as a zirconia sintered body used as a mill blank such as a denture material or an orthodontic bracket. Further, according to the zirconia powder of the present invention, a zirconia sintered body having translucency can be produced by atmospheric pressure sintering without using a large pressure sintering apparatus such as HIP.
- the “stabilizer concentration” of the zirconia powder in the present invention refers to a value expressed as mol% of the ratio of stabilizer / (ZrO 2 + stabilizer).
- “Additive content” refers to a value expressed as a weight% ratio of additive / (ZrO 2 + stabilizer + additive).
- the “relative density” is a ratio (%) of the actually measured density ( ⁇ ; g / cm 3 ) to the theoretical density ( ⁇ 0 ; g / cm 3 ), and is a value obtained by the following formula.
- Relative density (%) ( ⁇ / ⁇ 0 ) ⁇ 100
- the actual density ( ⁇ ) is a value measured by the Archimedes method.
- the theoretical density ( ⁇ 0 ) is a value obtained by the following equation (1).
- ⁇ 0 100 / [(A / 3.987) + (100 ⁇ A) / ⁇ X ] (1)
- ⁇ 0 is the theoretical density (g / cm 3 )
- 3.987 is the theoretical density (g / cm 3 ) of alumina
- ⁇ X is a zirconia sintered body containing Xmol% yttria.
- A is the alumina content (% by weight), which is the weight ratio of alumina to the zirconia sintered body containing Xmol% yttria.
- ⁇ X in the formula (1) shows different values due to the different yttria content or alumina content in the zirconia sintered body.
- the theoretical density ( ⁇ X ) of a zirconia sintered body having a yttria content of the following mol% was set to the following value.
- ⁇ X in yttria-containing zirconia sintered bodies other than the above is “Lattice Parameters and Density for Y 2 O 3 -Stabilized ZrO 2 ” Am. Ceram. Soc. 69 [4] 325-32 (1986), a value obtained by calculation can be used.
- ⁇ is the half width of the main XRD peak
- ⁇ is the Bragg angle of the main XRD peak.
- the peak is an XRD peak in which a tetragonal (111) plane and a cubic (111) plane overlap.
- the main XRD peak is subjected to waveform processing without performing tetragonal and cubic peak separation, and the Bragg angle ( ⁇ ) and the mechanical spread width of the main XRD peak after waveform processing are calculated.
- the half width ( ⁇ ) of the corrected main XRD peak may be obtained.
- the “average particle size” of the zirconia powder is a sphere having the same volume as a particle having a median value (median diameter; particle size corresponding to 50% of the cumulative curve) of the cumulative curve of the particle size distribution expressed on a volume basis. Diameter.
- the said average particle diameter is the value measured with the particle size distribution measuring apparatus by a laser diffraction method.
- the zirconia sintered body of the present invention contains yttria and alumina, the yttria content is more than 4.0 mol% and not more than 6.5 mol%, the alumina content is less than 0.1 wt%, The relative density of the aggregate is 99.82% or more, the bending strength is 500 MPa or more, and the total light transmittance for light having a wavelength of 600 nm is 37% or more and less than 40% when the sample thickness is 1.0 mm. is there.
- the translucent zirconia sintered body of the present invention functions as a stabilizer and exceeds 4.0 mol% to 6.5 mol% or less, preferably 4.1 mol% to 6.0 mol%, more preferably 4.5 mol% % Or more and 6.0 mol% or less of yttria.
- the yttria content is 4.0 mol% or less, the translucency of the zirconia sintered body decreases.
- 6.5 mol% is exceeded, translucency will become high too much. Therefore, when used as a denture for anterior teeth, a transparent feeling appears in the sintered body, resulting in an anterior denture having unnatural aesthetics.
- the yttria content in the present invention can be determined as the stabilizer concentration.
- the translucent zirconia sintered body of the present invention has an alumina content of less than 0.1 wt%, further 0.08 wt% or less, and further 0.06 wt% or less.
- Alumina is contained as an additive in the translucent zirconia sintered body of the present invention.
- the translucent zirconia sintered body of the present invention has high strength by containing alumina.
- the alumina content is 0.1 wt% or more, the translucency is lowered, and therefore, it becomes unnatural aesthetics as an anterior denture.
- the alumina content is preferably 0.05 wt% or less.
- content of the alumina in this invention can be calculated
- the content of alumina may be 0 wt% or more and less than 0.1 wt%, and further 0 wt% or more and 0.05 wt% or less.
- the translucent zirconia sintered body of the present invention has a relative density of 99.82% or more, and further 99.85% or more. When the relative density is less than 99.82%, the translucency of the zirconia sintered body is lowered.
- the translucent zirconia sintered body of the present invention preferably has a relative density of 99.90% or more, and more preferably 99.95% or more.
- the theoretical density used when determining the relative density has different values depending on the difference in the yttria content or the alumina content. The following values can be exemplified as the theoretical density of the translucent zirconia sintered body of the present invention.
- the translucent zirconia sintered body of the present invention is obtained by atmospheric pressure sintering without using pressure sintering such as HIP. Furthermore, by satisfying the above composition and having a relative density of 99.82% or more, the total light transmittance for light having a wavelength of 600 nm at a sample thickness of 1.0 mm (hereinafter simply referred to as “total light transmittance”). Also satisfies 37% or more and less than 40%.
- the translucent zirconia sintered body of the present invention has a total light transmittance of 37% or more and less than 40%, further 37% or more and 39.9% or less, and further 37.1% or more and 39.5% or less. . When the total light transmittance is 40% or more, it becomes a sintered body having transparency in addition to translucency. Since such a sintered body transmits light too much, it cannot be used as a front tooth denture.
- the translucent zirconia sintered body of the present invention can be used alone as a front denture without requiring a coating such as a glass coating. More preferable total light transmittance as an anterior denture that does not require coating is 37.3% or more and 39.2% or less, further 37.3% or more and 39.0% or less, and further 37.5% or more. It is 38.6% or less.
- the translucent zirconia sintered body of the present invention has a ratio of total light transmittance (hereinafter referred to as “D65 transmittance”) to D65 light with a sample thickness of 1.0 mm (hereinafter referred to as “D65 transmittance”) to the total light transmittance.
- D65 transmittance total light transmittance
- Transmissivity ratio is preferably 1.16 or more, more preferably 1.18 or more.
- the transmissivity ratio of the translucent zirconia sintered body of the present invention is 1.4 or less, and further 1.35 or less.
- the transmittance ratio is 1.16 or more and 1.4 or less, further 1.16 or more and 1.35 or less, and further 1.18 or more. It is preferably 1.35 or less, more preferably 1.2 or more and 1.35 or less, and even more preferably 1.25 or more and 1.35 or less.
- the translucent zirconia sintered body of the present invention has aesthetics closer to natural front teeth.
- permeability of the translucent zirconia sintered compact of this invention should just be a value which has said transmittance
- the D65 transmittance of the translucent zirconia sintered body of the present invention is, for example, preferably 42% to 56%, more preferably 42% to 54%, and even more preferably 44% to 52%.
- the translucent zirconia sintered body of the present invention has a bending strength of 500 MPa or more, and more preferably 550 MPa or more. Although the translucent zirconia sintered body of the present invention has moderate translucency and high relative density, the bending strength is not too high. If bending strength is 500 Mpa or more, it will become intensity
- the bending strength is preferably 600 MPa or more, more preferably 650 MPa or more, further 670 MPa or more, and even more preferably 700 MPa or more in order to obtain a strength suitable for an artificial tooth for anterior teeth.
- the bending strength of the translucent zirconia sintered body of the present invention is usually preferably 1070 MPa or less, more preferably 1020 MPa or less, further less than 1000 MPa, further 950 MPa or less, and further 900 MPa or less.
- the bending strength is preferably 500 MPa or more and 1070 MPa or less, more preferably 500 MPa or more and less than 1000 MPa, further 550 MPa or more and less than 1000 MPa, and even more preferably 550 MPa or more and 950 MPa or less.
- the said bending strength means three-point bending strength.
- the crystal grain size of the translucent zirconia sintered body of the present invention is excellent in relative density and bending strength, it is 0.3 to 1.0 ⁇ m, further 0.3 to 0.9 ⁇ m, and further 0.4 ⁇ m. It is preferably from 0.8 to 0.86 m, more preferably from 0.4 to 0.81 ⁇ m, and even more preferably from 0.4 to 0.8 ⁇ m.
- the translucent zirconia sintered body of the present invention has the yttria content, alumina content, relative density, total light transmittance, D65 transmittance, transmittance ratio, bending strength, and crystal grain size values and ranges described above. Any combination of the values shown in FIG.
- a method for producing a light-transmitting zirconia sintered body of the present invention a molded body is obtained by molding zirconia powder containing more than 4.0 mol% and 6.5 mol% yttria and less than 0.1 wt% alumina.
- the method which has a shaping
- a zirconia powder containing more than 4.0 mol% and 6.5 mol% yttria and less than 0.1 wt% alumina is formed to obtain a formed body. If a molded body having a desired shape is obtained, the molding method is arbitrary. Examples of the molding method include at least one of press molding by uniaxial pressing and CIP. Density of the molded body, it is 3.2 g / cm 3 greater, and further preferably not larger than 3.2 g / cm 3 Ultra 3.3 g / cm 3.
- the zirconia powder used for the forming step is a zirconia powder containing more than 4.0 mol% and 6.5 mol% yttria and less than 0.1 wt% alumina.
- Examples of preferable zirconia powder to be subjected to the forming step include the following zirconia powder. .
- the zirconia sintered body of the present invention can be obtained even if the sintering in the sintering step is only atmospheric pressure sintering.
- translucent zirconia sintering that has both translucency and strength suitable as an artificial tooth for front teeth without using special sintering methods such as pressure sintering such as HIP and SPS.
- pressure sintering such as HIP and SPS.
- the zirconia powder of the present invention is a zirconia powder containing 4.0 to 6.5 mol% yttria as a stabilizer and having an alumina content of less than 0.1 wt%.
- the zirconia powder of the present invention contains yttria exceeding 4.0 mol% and not more than 6.5 mol%, preferably not less than 4.1 mol% and not more than 6.0 mol%, more preferably not less than 4.5 mol% and not more than 6.0 mol%.
- Yttria functions as a stabilizer.
- the stabilizer is 4.0 mol% or less, the translucency of the obtained zirconia sintered body becomes too low.
- the stabilizer exceeds 6.5 mol%, a highly translucent zirconia sintered body having a translucent property higher than that required for anterior denture is obtained. Therefore, when it is used as a denture for anterior teeth, a sense of transparency appears, resulting in an unnatural denture. In addition, since the strength is too low, it cannot be used as a front denture.
- the zirconia powder of the present invention preferably has an alumina content of less than 0.1 wt%, more preferably 0.08 wt% or less, and even more preferably 0.06 wt% or less.
- alumina content is obtained when the zirconia powder of the present invention contains alumina.
- the alumina content is 0.1 wt% or more, the translucency of the obtained zirconia sintered body is lowered, so that the zirconia sintered body has unnatural aesthetics as a front denture.
- the content of alumina is preferably 0.05 wt% or less.
- the alumina content of the zirconia powder of the present invention is 0 wt% or more and less than 0.01 wt%, and more preferably 0 wt% or more and 0.05 wt% or less.
- the crystallite diameter of the zirconia powder of the present invention is 320 to 380 mm, more preferably 330 to 370 mm, or even 340 to 360 mm, or even 350 to 360 mm, because the density of the obtained zirconia sintered body becomes high. It is preferable.
- the zirconia powder of the present invention preferably has a BET specific surface area of 8 to 15 m 2 / g, more preferably 10 to 15 m 2 / g. When the BET specific surface area is 8 m 2 / g or more, the zirconia powder becomes a powder that can be easily sintered at a lower temperature.
- the BET specific surface area is 15 m 2 / g or less, and further 14 m 2 / g or less, the density of the obtained sintered body is unlikely to be low, and a translucent zirconia sintered body is easily obtained.
- the BET specific surface area is 9 m 2 / g to 15 m 2 / g, further 10 m 2 / g to 14 m. 2 / g or less is preferable.
- the zirconia powder of the present invention can provide a zirconia sintered body more suitable as a denture for anterior teeth by combining only the above-mentioned crystallite diameter and BET specific surface area by sintering under normal pressure sintering. .
- the zirconia powder having both the crystallite diameter and the BET specific surface area as described above is subjected to a coating treatment or the like only by normal pressure sintering without using a sintering method such as HIP or SPS. Therefore, it becomes easy to obtain a light-transmitting zirconia sintered body suitable as a denture for anterior teeth by itself.
- the total ratio of tetragonal crystal and cubic crystal (hereinafter also referred to as “(T + C) phase ratio”) contained in the crystal is 80% or more, and further 85%.
- the above is preferable.
- the (T + C) phase ratio has such a value, a sintered body having both translucency and bending strength suitable as a denture for anterior teeth can be obtained even when sintering is performed only at normal pressure sintering.
- a preferable (T + C) phase ratio is 90% or more, more than 90%, and further 95% or more.
- the (T + C) phase ratio is the total ratio of tetragonal crystals and cubic crystals to the total of monoclinic crystals, tetragonal crystals, and cubic crystals of zirconia, and can be determined from the following equation.
- (T + C) phase ratio (%) 100 ⁇ fm
- fm is a monoclinic crystal ratio (%)
- fm is an XRD peak intensity corresponding to the monoclinic phase (111) plane (hereinafter referred to as “Im (111)”), and an XRD peak intensity corresponding to the monoclinic phase (11-1) plane (hereinafter referred to as “Im (111)”).
- the average particle size of the zirconia powder of the present invention is 0.40 to 0.50 ⁇ m, more preferably 0.40 to 0.45 ⁇ m, and even more preferably 0.00. It is preferably 40 to 0.43 ⁇ m.
- the zirconia powder of the present invention is preferably spray-molded powder granules (hereinafter also simply referred to as “granules”).
- the zirconia powder of the present invention is preferably spray granulated granules containing an organic binder in addition to yttria as a stabilizer and alumina as an additive.
- the granules have high fluidity when forming a molded body, and can form a molded body having excellent shape retention after press molding.
- the average particle size of the granule is preferably 30 to 80 ⁇ m, and the light bulk density is preferably 1.10 to 1.40 g / cm 3 .
- the light bulk density is a density (Bulk Density) measured by a method according to JIS R1628.
- the organic binder examples include one or more selected from the group consisting of polyvinyl alcohol, polyvinyl butyrate, wax, and acrylic resin.
- an acrylic resin having a carboxyl group or a derivative thereof (for example, a salt, particularly an ammonium salt) in the molecule is preferable.
- the acrylic resin examples include one or more selected from the group consisting of polyacrylic acid, polymethacrylic acid, acrylic acid copolymer, methacrylic acid copolymer, and derivatives thereof.
- the amount of the organic binder added is preferably 0.5 to 10% by weight, particularly 1 to 5% by weight, based on the zirconia powder in the zirconia powder slurry.
- a zirconia sintered body having translucency suitable as an artificial tooth for anterior teeth can be obtained by sintering only under normal pressure sintering. That is, the zirconia powder of the present invention can provide a zirconia sintered body having high translucency suitable as a denture for anterior teeth without using pressure sintering such as HIP treatment.
- Density of the molded article obtained by molding the zirconia powder of the present invention may be a 3.2 g / cm 3 greater, 3.2 g / ccm 3 Super 3.3 g / cm 3 or less, more 3.2 g / cm 3 is preferably less ultra 3.27 g / cm 3.
- the density of the molded body is over 3.2 g / cm 3 , the translucent property of the obtained sintered body tends to be more suitable for anterior denture.
- the density of a molded object is 3.3 g / cm ⁇ 3 > or less, a sintered compact will not easily have the defect etc. which cause the strength fall.
- the molded body preferably has a (T + C) phase ratio of 90% or more and a molded body density of more than 3.2 g / cm 3 and not more than 3.25 g / cm 3 .
- the zirconia powder of the present invention includes, for example, a raw material step for obtaining a hydrated zirconia sol by hydrolysis of an aqueous zirconium salt solution, a calcining step for drying and calcining the hydrated zirconia sol to obtain a calcined powder, It is preferable to manufacture by the manufacturing method which has the grinding
- a hydrated zirconia sol is obtained by hydrolyzing the zirconium salt aqueous solution.
- the zirconium salt aqueous solution used for producing the hydrated zirconia sol include an aqueous solution containing at least one selected from the group consisting of a mixture of zirconium hydroxide and an acid, zirconium oxychloride, zirconyl nitrate, zirconium chloride and zirconium sulfate. .
- the addition amount of the yttria source may be the same as the yttria content in the zirconia powder.
- the yttria source may be any one that dissolves in an aqueous hydrated zirconium salt solution, and is at least one selected from the group consisting of yttrium chloride, yttrium oxide, yttrium nitrate and yttrium hydroxide, or at least yttrium chloride or yttrium oxide. One of them.
- the obtained hydrated zirconia sol is dried to obtain a dry powder, and then the calcined powder is obtained by calcining the dry powder. Drying in the calcination step can be performed by any method as long as moisture in the hydrated zirconia sol and residual moisture attached to the hydrated zirconia sol can be removed. An example of the drying temperature is 160 to 200 ° C.
- the calcined powder is obtained by calcining the dried powder of the hydrated zirconia sol obtained above.
- the calcination temperature is preferably 1050 to 1250 ° C, more preferably 1100 to 1200 ° C. When the calcination temperature is within this range, not only the zirconia aggregation is suppressed, but also the particle size of the obtained calcination powder tends to be uniform.
- the obtained calcined powder is pulverized.
- the zirconia powder of this invention is obtained.
- the calcination powder obtained above is pulverized until the average particle size becomes 0.40 to 0.50 ⁇ m.
- the pulverization method is arbitrary as long as the calcined powder has the above average particle size. Examples of the pulverization method include wet pulverization and / or dry pulverization, and wet pulverization.
- a particularly preferable grinding method includes wet grinding using zirconia balls, and the zirconia balls preferably have a diameter of 3 mm or less.
- the pulverization is preferably performed after the alumina source is added to the calcined powder. Thereby, zirconia and alumina are mixed more uniformly.
- the alumina source used as the additive may be an aluminum compound, for example, at least one selected from the group consisting of alumina, hydrated alumina, alumina sol, aluminum hydroxide, aluminum chloride, aluminum nitrate, and aluminum sulfate, preferably Can include at least one selected from the group consisting of alumina, hydrated alumina and alumina sol.
- alumina source can be added, pulverized, and dispersed and mixed.
- the method for producing zirconia powder of the present invention preferably further includes a granulation step.
- the zirconia powder of the present invention can be made into granules.
- zirconia powder may be made into a slurry and spray dried. Examples of spray drying include dropping the slurry into hot air at 160 to 200 ° C.
- the sintering step the compact obtained in the molding step is sintered at a sintering temperature of 1350 to 1500 ° C. under normal pressure. Thereby, the translucent zirconia sintered compact of this invention is obtained.
- the sintering temperature in the sintering step is preferably 1400 ° C. or higher and 1490 ° C. or lower, more preferably 1400 ° C. or higher and 1450 ° C. or lower.
- the heating rate in the sintering process is 800 ° C./hour or less, and further 600 ° C./hour or less.
- the holding time at the sintering temperature (hereinafter also simply referred to as “holding time”) varies depending on the sintering temperature. Examples of the holding time in the sintering step include 5 hours or less, 3 hours or less, and 2 hours or less.
- the translucent zirconia sintered body of the present invention is obtained by pressureless sintering.
- normal pressure sintering is a method of sintering by simply heating without applying an external force to the compact.
- a specific example of normal pressure sintering is sintering under atmospheric pressure.
- the sintering atmosphere may be a reducing atmosphere, that is, an atmosphere other than the reducing atmosphere may be used.
- the sintering atmosphere may be an oxygen atmosphere, and sintering in the air is preferable.
- sintering is performed under atmospheric pressure at a heating rate of 600 ° C./hour or less and a sintering temperature of 1400 ° C. or more and 1490 ° C. or less.
- the sintering process is performed only by atmospheric pressure sintering.
- a special sintering method such as HIP or other pressure sintering or SPS after atmospheric pressure sintering.
- pressure sintering and special sintering methods not only complicate the manufacturing process but also increase the manufacturing cost.
- a translucent zirconia sintered body having sufficient translucency and strength as an artificial tooth for anterior teeth even if only atmospheric pressure sintering is used. Can be obtained.
- the average particle size of the zirconia powder was measured using a Microtrac particle size distribution meter (manufactured by Honeywell, model: 9320-HRA). As pretreatment conditions for the sample, the pulverized slurry was suspended in distilled water and dispersed for 3 minutes using an ultrasonic homogenizer (manufactured by Nippon Seiki Seisakusho, model: US-150T). (Average particle size of granules) The average particle diameter of the zirconia granules was determined by a screening test method according to JIS Z8801.
- Crystallite diameter The powder sample was subjected to XRD measurement in the same manner as the identification of the crystal phase to obtain an XRD pattern. From the obtained XRD pattern, the half width of the peak (main XRD peak) corresponding to the tetragonal (111) plane and the cubic (111) plane was calculated. The crystallite diameter was calculated from the following formula using the half width. Using an X-ray diffractometer, the half width was obtained from the results of performing peak fitting after removing the measurement results from the background.
- Crystal grain size The crystal grain size of the zirconia sintered body is calculated by a planimetric method from an SEM observation figure obtained using a field emission scanning electron microscope (FESEM) (manufactured by JEOL Ltd., model: JSM-T220). Average particle diameter. As the measurement sample, a mirror-polished zirconia sintered body obtained by thermal etching was used.
- FESEM field emission scanning electron microscope
- the sintered body density was measured by Archimedes method.
- Total light transmittance The total light transmittance of the zirconia sintered body was measured using a spectrophotometer (manufactured by JASCO Corporation, model: V-650). The sample used was a 1 mm-thick disk-shaped product obtained by polishing both sides of a zirconia sintered body, transmitted light having a wavelength of 220 to 850 nm, and measured light collected by an integrating sphere.
- Example 1 (Preparation of zirconia powder) A hydrous zirconia sol was obtained by hydrolyzing the zirconium oxychloride aqueous solution. After adding yttrium chloride to the hydrated zirconia sol so that the yttria concentration was 4.1 mol%, it was dried at 180 ° C. The dried zirconia sol was calcined at 1120 ° C. for 2 hours. As a result, a zirconia calcined powder containing 4.1 mol% yttria was obtained. The obtained calcined powder was washed with distilled water and dried at 110 ° C. to obtain a zirconia washed powder. ⁇ -alumina was added to the zirconia water-washed powder so that the alumina content was 0.05% by weight to obtain a mixed powder.
- Distilled water was added so that the solid content concentration of the mixed powder was 45% by weight to obtain a slurry.
- the slurry was pulverized by a ball mill for 14 hours with a ball mill having a diameter of 2 mm so that the average particle size was 0.40 to 0.50 ⁇ m to obtain a pulverized slurry.
- the average particle size of the obtained pulverized slurry was measured and used as the average particle size of the zirconia powder.
- zirconia powder obtained by drying a part of the pulverized slurry at 110 ° C. was evaluated. The evaluation results are shown in Table 2.
- the obtained zirconia granules had an average particle size of 50 ⁇ m and a light bulk density of 1.25 g / cm 3 .
- Example 2 (Preparation of zirconia powder) A hydrous zirconia sol was obtained by hydrolyzing the zirconium oxychloride aqueous solution. After adding yttrium chloride to the hydrated zirconia gel so that the yttria concentration was 5.0 mol%, it was dried at 180 ° C. The dried zirconia gel was baked at 1120 ° C. for 2 hours. Thereby, a zirconia calcined powder containing 5.0 mol% yttria was obtained. The obtained calcined powder was washed with distilled water and dried at 110 ° C. to obtain a zirconia washed powder. ⁇ -alumina was added to the zirconia water-washed powder so that the alumina content was 0.05% by weight to obtain a mixed powder.
- Distilled water was added to obtain a slurry so that the solid content concentration of these mixed powders was 45% by weight.
- the slurry was pulverized by a ball mill for 17 hours with a ball mill having a diameter of 2 mm so that the average particle size was 0.40 to 0.50 ⁇ m to obtain a pulverized slurry.
- the average particle size of the obtained pulverized slurry was measured and used as the average particle size of the zirconia powder.
- zirconia powder obtained by drying a part of the pulverized slurry at 110 ° C. was evaluated. The evaluation results are shown in Table 2.
- the obtained zirconia granules had an average particle size of 48 ⁇ m and a light bulk density of 1.27 g / cm 3 .
- Example 3 (Preparation of zirconia powder) A hydrous zirconia sol was obtained by hydrolyzing the zirconium oxychloride aqueous solution. After adding yttrium chloride to the hydrated zirconia sol so that the yttria concentration was 6.0 mol%, it was dried at 180 ° C. The dried zirconia sol was calcined at 1120 ° C. for 2 hours. As a result, a zirconia calcined powder containing 6.0 mol% yttria was obtained. The obtained calcined powder was washed with distilled water and dried at 110 ° C. to obtain a zirconia washed powder. ⁇ -alumina was added to the zirconia water-washed powder so that the alumina content was 0.05% by weight to obtain a mixed powder.
- Distilled water was added to obtain a slurry so that the solid content concentration of these mixed powders was 45% by weight.
- the slurry was pulverized by a ball mill for 17 hours with a ball mill having a diameter of 2 mm so that the average particle size was 0.40 to 0.50 ⁇ m to obtain a pulverized slurry.
- the average particle size of the obtained pulverized slurry was measured and used as the average particle size of the zirconia powder.
- zirconia powder obtained by drying a part of the pulverized slurry at 110 ° C. was evaluated. The evaluation results are shown in Table 2.
- the obtained zirconia granules had an average particle diameter of 48 ⁇ m and a light bulk density of 1.26 g / cm 3 .
- Example 4 (Preparation of zirconia powder) A hydrous zirconia sol was obtained by hydrolyzing the zirconium oxychloride aqueous solution. After adding yttrium chloride to the hydrated zirconia gel so that the yttria concentration was 5.0 mol%, it was dried at 180 ° C. The dried zirconia gel was baked at 1160 ° C. for 2 hours. Thereby, a zirconia calcined powder containing 5.0 mol% yttria was obtained. The obtained calcined powder was washed with distilled water and dried at 110 ° C. to obtain a zirconia washed powder.
- Distilled water was added to obtain a slurry so that the solid content concentration of the washing powder was 45% by weight.
- the slurry was pulverized for 25 hours with a ball mill having a diameter of 2 mm so that the average particle size was 0.40 to 0.50 ⁇ m to obtain a pulverized slurry.
- the average particle size of the obtained pulverized slurry was measured and used as the average particle size of the zirconia powder.
- zirconia powder obtained by drying a part of the pulverized slurry at 110 ° C. was evaluated. The evaluation results are shown in Table 2.
- 3% by weight of a polyacrylic acid organic binder was added to the pulverized slurry, and this was dropped into hot air at 180 ° C. to carry out spray drying to obtain zirconia granules of this example.
- the obtained zirconia granules had an average particle size of 50 ⁇ m and a light bulk density of 1.28 g / cm 3
- Example 5 (Preparation of zirconia powder) A hydrous zirconia sol was obtained by hydrolyzing the zirconium oxychloride aqueous solution. After adding yttrium chloride to the hydrated zirconia gel so that the yttria concentration was 5.5 mol%, it was dried at 180 ° C. The dried zirconia gel was baked at 1160 ° C. for 2 hours. As a result, a zirconia calcined powder containing 5.5 mol% of yttria was obtained. The obtained calcined powder was washed with distilled water and dried at 110 ° C. to obtain a zirconia washed powder.
- Distilled water was added to obtain a slurry so that the solid content concentration of the washing powder was 45% by weight.
- the slurry was pulverized with a ball mill having a diameter of 2 mm so that the average particle size was 0.40 to 0.50 ⁇ m for 22 hours to obtain a pulverized slurry.
- the average particle diameter of the obtained pulverized slurry was measured and used as the average particle diameter of the zirconia powder.
- the zirconia powder obtained by drying a part of ground slurry at 110 degreeC was evaluated. The evaluation results are shown in Table 2.
- 3% by weight of a polyacrylic acid organic binder was added to the pulverized slurry, and this was dropped into hot air at 180 ° C. to carry out spray drying to obtain zirconia granules of this example.
- the obtained zirconia granules had an average particle size of 48 ⁇ m and a light bulk density of 1.24 g / cm 3 .
- Example 6 Preparation of zirconia powder
- a hydrous zirconia sol was obtained by hydrolyzing the zirconium oxychloride aqueous solution. After adding yttrium chloride to the hydrated zirconia gel so that the yttria concentration was 5.5 mol%, it was dried at 180 ° C. The dried zirconia gel was baked at 1160 ° C. for 2 hours. As a result, a zirconia calcined powder containing 5.5 mol% of yttria was obtained. ⁇ -alumina was added to the zirconia water-washed powder so that the alumina content was 0.05% by weight to obtain a mixed powder.
- Distilled water was added to obtain a slurry so that the solid content concentration of the washing powder was 45% by weight.
- the slurry was pulverized with a ball mill having a diameter of 2 mm so that the average particle size was 0.40 to 0.50 ⁇ m for 22 hours to obtain a pulverized slurry.
- the average particle diameter of the obtained pulverized slurry was measured and used as the average particle diameter of the zirconia powder.
- the zirconia powder obtained by drying a part of ground slurry at 110 degreeC was evaluated. The evaluation results are shown in Table 2.
- 3% by weight of a polyacrylic acid organic binder was added to the pulverized slurry, and this was dropped into hot air at 180 ° C. to carry out spray drying to obtain zirconia granules of this example.
- the obtained zirconia granules had an average particle size of 43 ⁇ m and a light bulk density of 1.26 g / cm 3 .
- Example 7 (Preparation of zirconia powder) A hydrous zirconia sol was obtained by hydrolyzing the zirconium oxychloride aqueous solution. After adding yttrium chloride to the hydrated zirconia gel so that the yttria concentration was 5.5 mol%, it was dried at 180 ° C. The dried zirconia gel was baked at 1120 ° C. for 2 hours. As a result, a zirconia calcined powder containing 5.5 mol% of yttria was obtained. ⁇ -alumina was added to the zirconia water-washed powder so that the alumina content was 0.05% by weight to obtain a mixed powder.
- Distilled water was added to obtain a slurry so that the solid content concentration of the washing powder was 45% by weight.
- the slurry was pulverized with a ball mill having a diameter of 2 mm so that the average particle size was 0.40 to 0.50 ⁇ m for 12 hours to obtain a pulverized slurry.
- the average particle diameter of the obtained pulverized slurry was measured and used as the average particle diameter of the zirconia powder.
- the zirconia powder obtained by drying a part of ground slurry at 110 degreeC was evaluated. The evaluation results are shown in Table 2.
- 3% by weight of a polyacrylic acid organic binder was added to the pulverized slurry, and this was dropped into hot air at 180 ° C. to carry out spray drying to obtain zirconia granules of this example.
- the obtained zirconia granules had an average particle size of 48 ⁇ m and a light bulk density of 1.24 g / cm 3 .
- Comparative Example 1 (Zirconia powder) A zirconia sintered body was prepared using zirconia powder (trade name: Zpex (registered trademark), manufactured by Tosoh Corporation) stabilized with 3.0 mol% of yttria and containing 0.05 wt% of Al 2 O 3 . The evaluation results of the zirconia powder are shown in Table 2.
- the zirconia powder was put in a metal mold having a diameter of 25 mm, and press molded at a molding pressure of 19.6 MPa to obtain a primary molded body.
- the obtained primary molded body was CIP molded at a pressure of 196 MPa to obtain a molded body.
- the compact was sintered under the conditions of 1450 ° C., a heating rate of 600 ° C./hr, and a holding time of 2 hours to obtain a zirconia sintered body of this comparative example.
- the evaluation results of the obtained zirconia sintered body are shown in Table 3.
- the zirconia sintered body of this comparative example had a total light transmittance of 35.8% and a strength of 1200 MPa.
- the zirconia sintered compact of this comparative example has the intensity
- Comparative Example 2 (Preparation of zirconia powder) A hydrous zirconia sol was obtained by hydrolyzing the zirconium oxychloride aqueous solution. After adding yttrium chloride to the hydrated zirconia sol so that the yttria concentration was 7.4 mol%, it was dried at 180 ° C. The dried hydrated zirconia sol was calcined at 1120 ° C. for 2 hours. As a result, a zirconia calcined powder containing 7.4 mol% yttria was obtained. The obtained calcined powder was washed with distilled water and dried at 110 ° C. to obtain a zirconia water-washed powder.
- Distilled water was added to obtain a slurry so that the solid content concentration of the washing powder was 45% by weight.
- the slurry was pulverized by a ball mill with a ball mill having a diameter of 2 mm so that the average particle size was 0.40 to 0.50 ⁇ m for 18 hours to obtain a pulverized slurry.
- the average particle size of the obtained pulverized slurry was measured and used as the average particle size of the zirconia powder.
- zirconia powder obtained by drying a part of the pulverized slurry at 110 ° C. was evaluated. The evaluation results are shown in Table 2.
- the obtained zirconia granules had an average particle diameter of 45 ⁇ m and a light bulk density of 1.24 g / cm 3 .
- the zirconia sintered body of this comparative example had a total light transmittance of 36.7%.
- the zirconia sintered body of this comparative example had a low total light transmittance, and was inferior in translucency as an anterior denture.
- Comparative Example 3 (Zirconia powder) A zirconia sintered body was prepared using zirconia powder (trade name: TZ-4YS, manufactured by Tosoh Corporation) stabilized with 4.0 mol% yttria. The evaluation results of the zirconia powder are shown in Table 2. (Production of sintered body) The zirconia powder was put into a mold having a diameter of 25 mm and press-molded at a molding pressure of 19.6 MPa to obtain a primary molded body. The obtained primary molded body was CIPed at a pressure of 196 MPa to obtain a molded body. The resulting molded body density is shown in Table 2.
- the obtained molded body was sintered under the conditions of 1550 ° C., a heating rate of 600 ° C./hr, and a holding time of 2 hours to obtain a sintered body of this comparative example.
- the evaluation results of the obtained zirconia sintered body are shown in Table 3.
- the zirconia sintered body of this comparative example had a total light transmittance of 36.0%.
- the zirconia sintered body of this comparative example had a low total light transmittance, and was inferior in translucency as an anterior denture.
- Comparative Example 4 (Zirconia powder) A zirconia sintered body was produced using zirconia powder (trade name: TZ-5YS, manufactured by Tosoh Corporation) stabilized with 5.0 mol% yttria. The evaluation results of the zirconia powder are shown in Table 2.
- the zirconia powder was put into a mold having a diameter of 25 mm and press-molded at a molding pressure of 19.6 MPa to obtain a primary molded body.
- the obtained primary molded body was CIPed at a pressure of 196 MPa to obtain a molded body.
- the resulting molded body density is shown in Table 2.
- the obtained molded body was sintered under the conditions of 1550 ° C., a heating rate of 600 ° C./hr, and a holding time of 2 hours to obtain a sintered body of this comparative example.
- the evaluation results of the obtained zirconia sintered body are shown in Table 3.
- the zirconia sintered body of this comparative example had a total light transmittance of 36.0%.
- the zirconia sintered body of this comparative example had a low total light transmittance, and was inferior in translucency as an anterior denture.
- Comparative Example 5 (Zirconia powder) A zirconia sintered body was produced using zirconia powder (trade name: TZ-6YS, manufactured by Tosoh Corporation) stabilized with 6.0 mol% yttria. The evaluation results of the zirconia powder are shown in Table 2. (Production of sintered body) The zirconia powder was put into a mold having a diameter of 25 mm and press-molded at a molding pressure of 19.6 MPa to obtain a primary molded body. The obtained primary molded body was CIPed at a pressure of 196 MPa to obtain a molded body. The resulting molded body density is shown in Table 2.
- the obtained molded body was sintered under the conditions of 1500 ° C., a temperature rising rate of 600 ° C./hr, and a holding time of 2 hours to obtain a sintered body of this comparative example.
- the evaluation results of the obtained zirconia sintered body are shown in Table 3.
- the zirconia sintered body of this comparative example had a total light transmittance of 25.3%.
- the zirconia sintered body of this comparative example has a low total light transmittance, is inferior in translucency as an anterior denture, and is not suitable for an anterior denture.
- the zirconia powder used in this comparative example could not obtain a highly translucent zirconia sintered body only by atmospheric pressure sintering.
- Comparative Example 6 A compact was obtained by molding the same zirconia powder as in Comparative Example 5 in the same manner as in Comparative Example 5.
- the obtained molded body was sintered under the conditions of 1550 ° C., a heating rate of 600 ° C./hr, and a holding time of 2 hours to obtain a sintered body of this comparative example.
- the evaluation results of the obtained zirconia sintered body are shown in Table 3.
- the zirconia sintered body of this comparative example had a total light transmittance of 24.5%.
- the zirconia sintered body of this comparative example had a low total light transmittance, and was inferior in translucency as an anterior denture.
- the zirconia powder used in this comparative example could not obtain a highly translucent zirconia sintered body only by atmospheric pressure sintering.
- the translucent zirconia sintered body of the present invention can be used as a denture including an anterior denture. Furthermore, it can be used as a dental material such as a denture mill blank or an orthodontic bracket. It should be noted that the entire content of the specification, claims, drawings and abstract of Japanese Patent Application No. 2013-265322 filed on December 24, 2013 is cited here as the disclosure of the specification of the present invention. Incorporated.
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Epidemiology (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Life Sciences & Earth Sciences (AREA)
- Dentistry (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Inorganic Chemistry (AREA)
- Composite Materials (AREA)
- Plastic & Reconstructive Surgery (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Dental Prosthetics (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)
Abstract
Description
一方、ジルコニアの多結晶体であるジルコニア焼結体は透光性がない。この原因として、結晶粒間及び結晶粒内に存在する気孔が光散乱を起こすことが知られている。そのため、気孔を減少させること、つまり焼結体密度を増加させることによって、多結晶のジルコニア焼結体に透光性を付与しようとする検討がこれまでなされている。
しかし、特許文献3や非特許文献1に開示されたジルコニア焼結体を前歯用義歯として使用するには、透明感が高すぎるため不自然であった。
さらに、本発明者らは、ジルコニア粉末中のイットリア濃度及びアルミナ濃度と、焼結体密度及び焼結体の全光線透過率との関係について詳細に検討した。その結果、常圧焼結で前歯用義歯として適した高透光性ジルコニア焼結体を得るためには、全光線透過率だけを改善することだけではなく、ジルコニア粉末の組成や物性、さらにはこれらの関係性を制御することが必要であることを見出し、本発明を完成するに到った。
[1] 4.0mol%を超え6.5mol%以下のイットリアと、0.1wt%未満のアルミナを含有し、相対密度が99.82%以上であり、厚さ1.0mmにおける600nm波長の光に対する全光線透過率が37%以上40%未満であり、曲げ強度が500MPa以上であることを特徴とする透光性ジルコニア焼結体。
[2] 結晶粒径が0.3~1.0μmである、上記[1]に記載の透光性ジルコニア焼結体。
[3] 試料厚さ1.0mmにおける600nm波長の光に対する全光線透過率に対する、試料厚さ1.0mmにおけるD65光線に対する全光線透過率の割合が、1.16以上である、上記[1]又は[2]に記載の透光性ジルコニア焼結体。
[5] 前記成形体の密度が3.2g/cm3超である、上記[4]に記載の製造方法。
[7] 結晶子径が320~380Åである、上記[6]に記載のジルコニア粉末。
[8] 平均粒径が0.40~0.50μmである、上記[6]又は[7]に記載のジルコニア粉末。
[9] 結晶中に含まれる正方晶及び立方晶の合計割合が80%以上である、上記[6]乃至[8]のいずれかに記載のジルコニア粉末。
[10] さらに、有機バインダーを含む、上記[6]乃至[9]のいずれかに記載のジルコニア粉末。
[11] 噴霧成形粉末顆粒である、上記[6]乃至[10]のいずれかに記載のジルコニア粉末。
[12] 上記[6]乃至[11]のいずれかに記載のジルコニア粉末を使用することを特徴とするジルコニア焼結体の製造方法。
[13] 上記[1]乃至[3]のいずれかに記載の透光性ジルコニア焼結体を含むことを特徴とする歯科材料。
[14] 義歯、義歯ミルブランク、前歯用義歯、前歯用義歯ミルブランク、又は歯列矯正ブラケットである、上記[13]に記載の歯科材料。
また、本発明のジルコニア粉末によれば、HIP等の大掛かりな加圧焼結装置を用いないで、常圧焼結で透光性を有するジルコニア焼結体を製造できる。
「添加物含有量」とは、添加物/(ZrO2+安定化剤+添加物)の比率を重量%として表した値をいう。
相対密度(%)=(ρ/ρ0)×100
ここで、実測密度(ρ)はアルキメデス法により測定される値である。また、理論密度(ρ0)は以下の(1)式によって求まる値である。
ρ0=100/[(A/3.987)+(100-A)/ρX] (1)
さらに、ジルコニア焼結体中のイットリア含有量、あるいはアルミナ含有量が異なることにより、(1)式におけるρXは異なる値を示す。本発明において、イットリアの含有量が下記のmol%であるジルコニア焼結体の理論密度(ρX)は以下の値とした。
イットリア含有量 3.5mol% :ρX=6.086g/cm3
イットリア含有量 4.0mol% :ρX=6.080g/cm3
イットリア含有量 4.1mol% :ρX=6.080g/cm3
イットリア含有量 4.5mol% :ρX=6.072g/cm3
イットリア含有量 5.0mol% :ρX=6.062g/cm3
イットリア含有量 5.5mol% :ρX=6.052g/cm3
イットリア含有量 6.0mol% :ρX=6.043g/cm3
イットリア含有量 6.5mol% :ρX=6.033g/cm3
イットリア含有量 7.4mol% :ρX=6.019g/cm3
結晶子径=κλ/βcosθ (2)
(2)式において、κはシェーラー定数(κ=1)、λは測定X線の波長(CuKα線を線源とした場合のλ=1.541862Å)、βはメインXRDピークの半値幅、及びθはメインXRDピークのブラッグ角である。
なお、上記の様に、本発明において、相対密度を求める場合に使用する理論密度は、イットリア含有量、あるいはアルミナ含有量の違いにより異なる値を有する。本発明の透光性ジルコニア焼結体の理論密度として、以下の値が例示できる。
本発明の透光性ジルコニア焼結体は、全光線透過率が37%以上40%未満、更には37%以上39.9%以下、また更には37.1%以上39.5%以下である。全光線透過率が40%以上の場合、透光性(Translucency)に加え、透明性(Transparency)を有する焼結体となる。このような焼結体は、光を透過し過ぎるため、前歯用義歯として使用することができなくなる。
本発明の透光性ジルコニア焼結体のD65透過率は、上記の透過率比を有する値であればよい。本発明の透光性ジルコニア焼結体のD65透過率としては、例えば、42%以上56%以下、更には42以上54%以下、また更には44%以上52%以下が好ましい。
前歯用義歯としては、例えば、曲げ強度が500MPa以上1070MPa以下、更には500MPa以上1000MPa未満、また更には550MPa以上1000MPa未満、また更には550MPa以上950MPa以下であることが好ましい。なお、上記曲げ強度は、三点曲げ強度を意味するものである。
本発明の透光性ジルコニア焼結体の製造方法としては、4.0mol%を超え6.5mol%のイットリア、及び0.1wt%未満のアルミナを含有するジルコニア粉末を成形して成形体を得る成形工程、及び該成形体を、常圧下、焼結温度1350℃以上1500℃以下で焼結する焼結工程、を有する方法が挙げられる。
成形体の密度は、3.2g/cm3超であること、更には3.2g/cm3超3.3g/cm3以下であることが好ましい。
本発明のジルコニア粉末は、安定化剤として4.0mol%を超え6.5mol%以下のイットリアを含み、アルミナの含有量が0.1wt%未満であるジルコニア粉末である。
一方、安定化剤が6.5mol%を超えると、前歯用義歯として必要とされる透光性以上の高透光性のジルコニア焼結体が得られる。そのため、前歯用義歯として使用する場合、透明感が現れ、不自然な義歯となる。これに加え、強度が低下しすぎるため、前歯用義歯として使用できない。
一方で、アルミナ含有量が0.1wt%以上では、得られるジルコニア焼結体の透光性が低下するため、前歯用義歯として不自然な審美性を有するジルコニア焼結体となる。前歯用義歯として適した審美性を有する透光性ジルコニア焼結体を得るためには、アルミナの含有量は0.05wt%以下であることが好ましい。本発明のジルコニア粉末のアルミナ含有量としては、0wt%以上0.01wt%未満であり、更には0wt%以上0.05wt%以下が好ましい。
本発明のジルコニア粉末は、BET比表面積が8~15m2/gであること、さらには10~15m2/gであることが好ましい。BET比表面積が8m2/g以上であることで、ジルコニア粉末がより低温で焼結しやすい粉末となる。一方、BET比表面積が15m2/g以下、更には14m2/g以下であれば、得られる焼結体の密度が低くなりにくく、透光性を有するジルコニア焼結体が得られやすくなる。前歯用義歯として適した透光性及び密度を有する透光性ジルコニア焼結体が得られやすくするため、BET比表面積は9m2/g以上15m2/g以下、更には10m2/g以上14m2/g以下であることが好ましい。
(T+C)相率(%) = 100 - fm
上記式において、fmは単斜晶率(%)である。fmは、単斜晶相(111)面に相当するXRDピーク強度(以下、「Im(111)」とする。)、単斜晶相(11-1)面に相当するXRDピーク強度(以下、「Im(11-1)」とする。)、並びに、正方晶(111)面に相当するXRDピークと立方晶の(111)面に相当するXRDピークの強度(以下、「It+c(111)」とする。)から、以下の式により求めることができる。
fm(%)=[Im(111)+Im(11-1)]
÷[Im(111)+Im(11-1)It+c(111)]×100
なお、正方晶(111)面に相当するXRDピークと立方晶の(111)面に相当するXRDピークとは重複したピークである。It+c(111)は、これらを分離せずにひとつのピークとみなして求めた強度である。
本発明のジルコニア粉末は、特に安定化剤としてイットリア、及び添加剤としてアルミナの他に、有機バインダーを含む噴霧造粒顆粒であることが好ましい。該顆粒は、成形体を形成する際の流動性が高くなり、プレス成形後の保形性に優れた成形体の形成が可能である。顆粒の平均粒径は30~80μm、軽装嵩密度は1.10~1.40g/cm3であることが好ましい。なお、軽装嵩密度とは、JIS R1628に準じた方法により測定される密度(Bulk Density)である。
有機バインダーの添加量は、ジルコニア粉末スラリー中のジルコニア粉末に対し、0.5~10重量%が好ましく、特に1~5重量%が好ましい。
水和ジルコニアゾルを得るにあたり、加水分解前又は加水分解中にイットリア源をジルコニウム塩水溶液に添加することが好ましい。イットリア源の添加量は、ジルコニア粉末におけるイットリア含有量と同程度の量であればよい。イットリア源としては、水和ジルコニウム塩水溶液中で溶解するものであればよく、塩化イットリウム、酸化イットリウム、硝酸イットリウム及び水酸化イットリウムからなる群から選ばれる少なくとも1種か、塩化イットリウム又は酸化イットリウムの少なくともいずれかであることが挙げられる。
仮焼工程における乾燥は、水和ジルコニアゾル中の水分、及び、水和ジルコニアゾル中に付着した残留水分を除去できれば任意の方法で乾燥することができる。乾燥温度は、160~200℃であることが例示できる。
仮焼工程では、上記で得られた水和ジルコニアゾルの乾燥粉末を仮焼することで、仮焼粉末を得る。仮焼温度は1050~1250℃が好ましく、1100~1200℃であることがより好ましい。仮焼温度がこの範囲であることで、ジルコニアの凝集が抑制されるだけでなく、得られる仮焼粉の粒径が均一になりやすい。
また、粉砕はアルミナ源を仮焼粉末に添加した後に行うことが好ましい。これにより、ジルコニア及びアルミナがより均一に混合される。
本発明の透光性ジルコニア焼結体は常圧焼結で得られる。ここで、常圧焼結とは成形体に対して外的な力を加えずに単に加熱することにより焼結する方法である。具体的な常圧焼結として、大気圧下での焼結を挙げることができる。
ジルコニア粉末の平均粒径は、マイクロトラック粒度分布計(Honeywell社製,型式:9320-HRA)を用いて測定した。試料の前処理条件としては、粉砕スラリーを蒸留水に懸濁させ、超音波ホモジナイザー(日本精機製作所社製,型式:US-150T)を用いて3分間分散させた。
(顆粒の平均粒径)
ジルコニア顆粒の平均粒径は、JIS Z 8801に準じた、ふるい分け試験方法によって求めた。
粉末試料のBET比表面積は、BET1点法の窒素吸着により測定した。測定装置には一般的なガス吸着式比表面積測定装置(装置名:トライスター3000、マイクロメリティックス社製)を用いた。測定に先立ち、250℃で60分間加熱の脱気処理を行うことにより、粉末試料を前処理した。
結晶子径(Å)=κλ/(βcosθ)
上記式において、κはシェーラー定数(=1)、λはCuKα線を線源とした場合のλであり、1.541862Åである。また、θはメインXRDピークのθ値であり、30.1~30.2°である。
一般的なX線回折装置(商品名:MXP-3、マックサイエンス社製)を使用し、試料の粉末X線回折測定による結晶相を測定した。測定条件は以下のとおりとした。
線源 : CuKα線(λ=1.541862Å)
測定モード : ステップスキャン
スキャン条件: 毎秒0.04°
発散スリット: 1.00deg
散乱スリット: 1.00deg
受光スリット: 0.30mm
計測時間 : 3.0秒
測定範囲 : 2θ=26°~33°
上記XRD測定により得られたXRDパターンから、以下の式より(T+C)相率を求めた。
(T+C)相率(%) = 100 - fm
上記式において、fmは単斜晶率(%)であり、以下の式により求めた。
fm(%)=[Im(111)+Im(11-1)]
÷[Im(111)+Im(11-1)It+c(111)]×100
粉末試料について、結晶相の同定と同様な方法でXRD測定し、XRDパターンを得た。得られたXRDパターンから正方晶の(111)面及び立方晶の(111)面に相当するピーク(メインXRDピーク)の半値幅を算出した。当該半値幅を用い以下の式より結晶子径を算出した。X線回折装置を用い、半価幅は測定結果をバックグランド除去した後、ピークフィッティング処理を行った結果から求めた。
ジルコニア焼結体の結晶粒径は、電解放出形走査型電子顕微鏡(FESEM)(日本電子社製、型式:JSM-T220)を用いて得られた、SEM観察図から、プラニメトリック法により算出した平均粒径である。測定試料には、鏡面研磨したジルコニア焼結体を熱エッチング処理したものを使用した。
焼結体密度は、アルキメデス法で測定した。
(全光線透過率)
ジルコニア焼結体の全光線透過率は、分光光度計(日本分光(株)製、型式:V-650)を用いて測定した。試料はジルコニア焼結体を両面研磨した厚み1mmの円盤形状のものを用いて、波長220~850nmの光を透過させて、積分球で集光した光を測定した。
濁度計(日本電色(株)製、型式:NDH2000)を用いて、JIS K 7361に準拠してD65光源での全光線透過率を測定した。測定には全光線透過率の測定で使用した試料同一の試料を使用した。
(三点曲げ強度)
ジルコニア焼結体の強度は、JIS R 1601に記載されている方法に基づいて、3点曲げ測定法で評価した。
(ジルコニア粉末の調製)
オキシ塩化ジルコニウム水溶液を加水分解反応して水和ジルコニアゾルを得た。イットリア濃度が4.1mol%になるように、塩化イットリウムを当該水和ジルコニアゾルに添加した後に、これを180℃で乾燥した。乾燥後のジルコニアゾルを1120℃で2時間焼成した。これにより、4.1mol%のイットリアを含むジルコニア仮焼粉末を得た。
得られた仮焼粉末を蒸留水で水洗し、110℃で乾燥してジルコニア水洗粉末とした。アルミナ含有量が0.05重量%となるように、当該ジルコニア水洗粉末にα-アルミナを添加して混合粉末を得た。
上記粉砕スラリーにポリアクリル酸系有機バインダーを3重量%添加して、これを180℃の熱風に滴下することで噴霧乾燥を実施し、本実施例のジルコニア顆粒を得た。得られたジルコニア顆粒は平均粒径が50μm、軽装嵩密度が1.25g/cm3であった。
得られたジルコニア顆粒5gを直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を、196MPaの成形圧力でCIPして成形体を得た。得られた成形体密度を表2に示した。
得られた成形体を1450℃、昇温速度600℃/hr、及び保持時間2時間の条件で焼結し、本実施例のジルコニア焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。得られたジルコニア焼結体は、全光線透過率は37.3%であった。全光線透過率が37%以上40%未満であることから、前歯用義歯に好適である。
(ジルコニア粉末の調製)
オキシ塩化ジルコニウム水溶液を加水分解反応して水和ジルコニアゾルを得た。イットリア濃度が5.0mol%になるように、塩化イットリウムを当該水和ジルコニアゲルに添加した後に、これを180℃で乾燥した。乾燥後のジルコニアゲルを1120℃で2時間焼成した。これにより、5.0mol%のイットリアを含むジルコニア仮焼粉末を得た。
得られた仮焼粉末を蒸留水で水洗し、110℃で乾燥してジルコニア水洗粉末とした。アルミナ含有量が0.05重量%となるように、当該ジルコニア水洗粉末にα-アルミナを添加して混合粉末を得た。
上記粉砕スラリーにポリアクリル酸系有機バインダーを3重量%添加して、これを180℃の熱風に滴下することで噴霧乾燥を実施し、本実施例のジルコニア顆粒を得た。得られたジルコニア顆粒は平均粒径が48μm、軽装嵩密度が1.27g/cm3であった。
得られたジルコニア顆粒5gを直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を、196MPaの成形圧力でCIPして成形体を得た。得られた成形体密度を表2に示した。
得られた成形体を1450℃、昇温速度600℃/hr、及び保持時間2時間の条件で焼結し、本実施例のジルコニア焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。得られたジルコニア焼結体は、全光線透過率は37.6%であった。全光線透過率が37%以上40%未満であることから、前歯用義歯に好適である。
(ジルコニア粉末の調製)
オキシ塩化ジルコニウム水溶液を加水分解反応して水和ジルコニアゾルを得た。イットリア濃度が6.0mol%になるように、塩化イットリウムを当該水和ジルコニアゾルに添加した後に、これを180℃で乾燥した。乾燥後のジルコニアゾルを1120℃で2時間焼成した。これにより、6.0mol%のイットリアを含むジルコニア仮焼粉末を得た。
得られた仮焼粉末を蒸留水で水洗し、110℃で乾燥してジルコニア水洗粉末とした。アルミナ含有量が0.05重量%となるように、当該ジルコニア水洗粉末にα-アルミナを添加して混合粉末を得た。
上記粉砕スラリーにポリアクリル酸系有機バインダーを3重量%添加して、これを180℃の熱風に滴下することで噴霧乾燥を実施し、本実施例のジルコニア顆粒を得た。得られたジルコニア顆粒は平均粒径が48μm、軽装嵩密度が1.26g/cm3であった。
得られたジルコニア顆粒5gを直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を、196MPaの成形圧力でCIPして成形体を得た。得られた成形体密度を表2に示した。
得られた成形体を1450℃、昇温速度600℃/hr、及び保持時間2時間の条件で焼結し、本実施例のジルコニア焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。得られたジルコニア焼結体は、全光線透過率は38.5%であった。全光線透過率が37%以上40%未満であることから、前歯用義歯に好適である。
(ジルコニア粉末の調製)
オキシ塩化ジルコニウム水溶液を加水分解反応して水和ジルコニアゾルを得た。イットリア濃度が5.0mol%になるように、塩化イットリウムを当該水和ジルコニアゲルに添加した後に、これを180℃で乾燥した。乾燥後のジルコニアゲルを1160℃で2時間焼成した。これにより、5.0mol%のイットリアを含むジルコニア仮焼粉末を得た。得られた仮焼粉末を蒸留水で水洗し、110℃で乾燥してジルコニア水洗粉末とした。
上記粉砕スラリーにポリアクリル酸系有機バインダーを3重量%添加して、これを180℃の熱風に滴下することで噴霧乾燥を実施し、本実施例のジルコニア顆粒を得た。得られたジルコニア顆粒は平均粒径が50μm、軽装嵩密度が1.28g/cm3であった。
得られたジルコニア顆粒5gを直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を、196MPaの成形圧力でCIPして成形体を得た。得られた成形体密度を表2に示した。
得られた成形体を1450℃、昇温速度600℃/hr、及び保持時間2時間の条件で焼結し、本実施例のジルコニア焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。得られたジルコニア焼結体は、全光線透過率は37.5%であった。全光線透過率が37%以上40%未満であることから、前歯用義歯に好適である。
(ジルコニア粉末の調製)
オキシ塩化ジルコニウム水溶液を加水分解反応して水和ジルコニアゾルを得た。イットリア濃度が5.5mol%になるように、塩化イットリウムを当該水和ジルコニアゲルに添加した後に、これを180℃で乾燥した。乾燥後のジルコニアゲルを1160℃で2時間焼成した。これにより、5.5mol%のイットリアを含むジルコニア仮焼粉末を得た。得られた仮焼粉末を蒸留水で水洗し、110℃で乾燥してジルコニア水洗粉末とした。
上記粉砕スラリーにポリアクリル酸系有機バインダーを3重量%添加して、これを180℃の熱風に滴下することで噴霧乾燥を実施し、本実施例のジルコニア顆粒を得た。得られたジルコニア顆粒は平均粒径が48μm、軽装嵩密度が1.24g/cm3であった。
得られたジルコニア顆粒5gを直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を、196MPaの成形圧力でCIPして成形体を得た。得られた成形体密度を表2に示した。
得られた成形体を1450℃、昇温速度600℃/hr、及び保持時間2時間の条件で焼結し、本実施例のジルコニア焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。得られたジルコニア焼結体は、全光線透過率は39.2%であった。全光線透過率が37%以上40%未満であることから、前歯用義歯に好適である。
(ジルコニア粉末の調製)
オキシ塩化ジルコニウム水溶液を加水分解反応して水和ジルコニアゾルを得た。イットリア濃度が5.5mol%になるように、塩化イットリウムを当該水和ジルコニアゲルに添加した後に、これを180℃で乾燥した。乾燥後のジルコニアゲルを1160℃で2時間焼成した。これにより、5.5mol%のイットリアを含むジルコニア仮焼粉末を得た。アルミナ含有量が0.05重量%となるように、当該ジルコニア水洗粉末にα-アルミナを添加して混合粉末を得た。
上記粉砕スラリーにポリアクリル酸系有機バインダーを3重量%添加して、これを180℃の熱風に滴下することで噴霧乾燥を実施し、本実施例のジルコニア顆粒を得た。得られたジルコニア顆粒は平均粒径が43μm、軽装嵩密度が1.26g/cm3であった。
得られたジルコニア顆粒5gを直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を、196MPaの成形圧力でCIPして成形体を得た。得られた成形体密度を表2に示した。得られた成形体を1450℃、昇温速度600℃/hr、及び保持時間2時間の条件で焼結し、本実施例のジルコニア焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。得られたジルコニア焼結体は、全光線透過率は37.5%であった。全光線透過率が37%以上40%未満であることから、前歯用義歯に好適である。
(ジルコニア粉末の調製)
オキシ塩化ジルコニウム水溶液を加水分解反応して水和ジルコニアゾルを得た。イットリア濃度が5.5mol%になるように、塩化イットリウムを当該水和ジルコニアゲルに添加した後に、これを180℃で乾燥した。乾燥後のジルコニアゲルを1120℃で2時間焼成した。これにより、5.5mol%のイットリアを含むジルコニア仮焼粉末を得た。アルミナ含有量が0.05重量%となるように、当該ジルコニア水洗粉末にα-アルミナを添加して混合粉末を得た。
上記粉砕スラリーにポリアクリル酸系有機バインダーを3重量%添加して、これを180℃の熱風に滴下することで噴霧乾燥を実施し、本実施例のジルコニア顆粒を得た。得られたジルコニア顆粒は平均粒径が48μm、軽装嵩密度が1.24g/cm3であった。
得られたジルコニア顆粒5gを直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を、196MPaの成形圧力でCIPして成形体を得た。得られた成形体密度を表2に示した。得られた成形体を1450℃、昇温速度600℃/hr、及び、保持時間2時間の条件で焼結し、本実施例のジルコニア焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。得られたジルコニア焼結体は、全光線透過率は37.5%であった。全光線透過率が37%以上40%未満であることから、前歯用義歯に好適である。
(ジルコニア粉末)
3.0mol%のイットリアで安定化され、Al2O3を0.05wt%含むジルコニア粉末(商品名:Zpex(登録商標)、東ソー社製)を使用して、ジルコニア焼結体を作製した。当該ジルコニア粉末の評価結果を表2に示した。
当該ジルコニア粉末を、直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体は、圧力196MPaでCIP成形し、成形体を得た。
次にその成形体を1450℃、昇温速度600℃/hr、及び保持時間2時間の条件で焼結して、本比較例のジルコニア焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。
本比較例のジルコニア焼結体は、全光線透過率は35.8%及び強度が1200MPaであった。このように、本比較例のジルコニア焼結体は奥歯用義歯として適した強度を有している一方、前歯用義歯としての透光性に劣るものであった。
(ジルコニア粉末の調製)
オキシ塩化ジルコニウム水溶液を加水分解反応して水和ジルコニアゾルを得た。イットリア濃度が7.4mol%になるように塩化イットリウムを当該水和ジルコニアゾルに添加した後に、これを180℃で乾燥した。乾燥後の水和ジルコニアゾルを1120℃で2時間焼成した。これにより、7.4mol%のイットリアを含むジルコニア仮焼粉末を得た。得られた仮焼粉末を蒸留水で水洗し、110℃で乾燥したてジルコニア水洗粉末を得た。
上記粉砕スラリーにポリアクリル酸系有機バインダーを3重量%添加して、これを180℃の熱風に滴下することで噴霧乾燥を実施し、本実施例のジルコニア顆粒を得た。得られたジルコニア顆粒は平均粒径が45μm、軽装嵩密度が1.24g/cm3であった。
得られたジルコニア顆粒5gを直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を圧力196MPaでCIPして成形体を得た。得られた成形体密度を表2に示した。
得られた成形体を1450℃、昇温速度600℃/hr、及び、保持時間2時間の条件で焼結して、本比較例のジルコニア焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。本比較例のジルコニア焼結体は、全光線透過率は36.7%であった。このように、本比較例のジルコニア焼結体は全光線透過率が低く、前歯用義歯としての透光性に劣るものであった。
(ジルコニア粉末)
4.0mol%のイットリアで安定化されたジルコニア粉末(商品名:TZ-4YS、東ソー社製)を使用してジルコニア焼結体を作製した。
当該ジルコニア粉末の評価結果を表2に示した。
(焼結体の作製)
当該ジルコニア粉末を直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を圧力196MPaでCIPして成形体を得た。得られた成形体密度を表2に示した。
本比較例のジルコニア焼結体は、全光線透過率は36.0%であった。このように、本比較例のジルコニア焼結体は全光線透過率が低く、前歯用義歯としての透光性に劣るものであった。
(ジルコニア粉末)
5.0mol%のイットリアで安定化されたジルコニア粉末(商品名:TZ-5YS、東ソー社製)を使用してジルコニア焼結体を作製した。
当該ジルコニア粉末の評価結果を表2に示した。
当該ジルコニア粉末を直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を圧力196MPaでCIPして成形体を得た。得られた成形体密度を表2に示した。
得られた成形体を1550℃、昇温速度600℃/hr、及び保持時間2時間の条件で焼結して本比較例の焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。
本比較例のジルコニア焼結体は、全光線透過率は36.0%であった。このように、本比較例のジルコニア焼結体は全光線透過率が低く、前歯用義歯としての透光性に劣るものであった。
(ジルコニア粉末)
6.0mol%のイットリアで安定化されたジルコニア粉末(商品名:TZ-6YS、東ソー社製)を使用してジルコニア焼結体を作製した。
当該ジルコニア粉末の評価結果を表2に示した。
(焼結体の作製)
当該ジルコニア粉末を直径25mmの金型に入れ、19.6MPaの成形圧力でプレス成形して一次成形体を得た。得られた一次成形体を圧力196MPaでCIPして成形体を得た。得られた成形体密度を表2に示した。得られた成形体を1500℃、昇温速度600℃/hr、及び、保持時間2時間の条件で焼結して本比較例の焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。
本比較例で使用したジルコニア粉末は、常圧焼結のみでは透光性の高いジルコニア焼結体が得られなかった。
比較例5と同じジルコニア粉末を比較例5と同じ方法で成形を行うことにより、成形体を得た。得られた成形体を、1550℃、昇温速度600℃/hr、及び保持時間2時間の条件で焼結して本比較例の焼結体を得た。得られたジルコニア焼結体の評価結果を表3に示した。
本比較例のジルコニア焼結体は、全光線透過率は24.5%であった。このように、本比較例のジルコニア焼結体は全光線透過率が低く、前歯用義歯としての透光性に劣るものであった。
本比較例で使用したジルコニア粉末は、常圧焼結のみでは透光性の高いジルコニア焼結体が得られなかった。
なお、2013年12月24日に出願された日本特許出願2013-265322号の明細書、特許請求の範囲、図面及び要約書の全内容をここに引用し、本発明の明細書の開示として、取り入れるものである。
Claims (14)
- 4.0mol%を超え6.5mol%以下のイットリアと、0.1wt%未満のアルミナを含有し、相対密度が99.82%以上であり、厚さ1.0mmにおける600nm波長の光に対する全光線透過率が37%以上40%未満であり、かつ曲げ強度が500MPa以上であることを特徴とする透光性ジルコニア焼結体。
- 結晶粒径が0.3~1.0μmであることを特徴とする請求項1に記載の透光性ジルコニア焼結体。
- 試料厚さ1.0mmにおける600nm波長の光に対する全光線透過率に対する、試料厚さ1.0mmにおけるD65光線に対する全光線透過率の割合が、1.16以上であることを特徴とする請求項1又は2に記載の透光性ジルコニア焼結体。
- 請求項1乃至3のいずれか一項に記載の透光性ジルコニア焼結体の製造方法であり、
4.0mol%を超え6.5mol%のイットリアと、0.1wt%未満のアルミナを含有するジルコニア粉末を成形して成形体を得る成形工程、及び該成形体を、常圧下、焼結温度1350℃以上1500℃以下で焼結する焼結工程、を有することを特徴とする製造方法。 - 前記成形体の密度が3.2g/cm3超であることを特徴とする請求項4に記載の製造方法。
- 4.0mol%を超え6.5mol%以下のイットリアと、0.1wt%未満のアルミナを含有し、BET比表面積が8~15m2/gであることを特徴とするジルコニア粉末。
- 結晶子径が320~380Åであることを特徴とする請求項6に記載のジルコニア粉末。
- 平均粒径が0.40~0.50μmであることを特徴とする請求項6又は7に記載のジルコニア粉末。
- 結晶中に含まれる正方晶及び立方晶の合計割合が80%以上であることを特徴とする請求項6乃至8のいずれか一項に記載のジルコニア粉末。
- さらに、有機バインダーを含むことを特徴とする請求項6乃至9のいずれか一項に記載のジルコニア粉末。
- 噴霧成形粉末顆粒であることを特徴とする請求項6乃至10のいずれか一項に記載のジルコニア粉末。
- 請求項6乃至11のいずれか一項に記載のジルコニア粉末を使用することを特徴とするジルコニア焼結体の製造方法。
- 請求項1乃至3のいずれか一項に記載の透光性ジルコニア焼結体を含むことを特徴とする歯科材料。
- 義歯、義歯ミルブランク、前歯用義歯、前歯用義歯ミルブランク、又は歯列矯正ブラケットである請求項13に記載の歯科材料。
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201480069715.0A CN105829264B (zh) | 2013-12-24 | 2014-12-19 | 透光性氧化锆烧结体和氧化锆粉末、及其用途 |
KR1020167010902A KR102595006B1 (ko) | 2013-12-24 | 2014-12-19 | 투광성 지르코니아 소결체 및 지르코니아 분말, 그리고 그의 용도 |
CN202110376123.5A CN113185284B (zh) | 2013-12-24 | 2014-12-19 | 透光性氧化锆烧结体和氧化锆粉末、及其用途 |
KR1020237029372A KR20230129196A (ko) | 2013-12-24 | 2014-12-19 | 투광성 지르코니아 소결체 및 지르코니아 분말, 그리고 그의 용도 |
EP14874020.2A EP3088373B1 (en) | 2013-12-24 | 2014-12-19 | Translucent zirconia sintered body and zirconia powder, and use therefor |
US15/104,036 US9737383B2 (en) | 2013-12-24 | 2014-12-19 | Translucent zirconia sintered body and zirconia powder, and use therefor |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2013265322 | 2013-12-24 | ||
JP2013-265322 | 2013-12-24 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2015098765A1 true WO2015098765A1 (ja) | 2015-07-02 |
Family
ID=53478622
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2014/083763 WO2015098765A1 (ja) | 2013-12-24 | 2014-12-19 | 透光性ジルコニア焼結体及びジルコニア粉末、並びにその用途 |
Country Status (6)
Country | Link |
---|---|
US (1) | US9737383B2 (ja) |
EP (1) | EP3088373B1 (ja) |
JP (2) | JP6543926B2 (ja) |
KR (2) | KR102595006B1 (ja) |
CN (2) | CN113185284B (ja) |
WO (1) | WO2015098765A1 (ja) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105997275A (zh) * | 2016-06-26 | 2016-10-12 | 江苏思麦尔生命科技有限公司 | 一种便于拆卸的透明氧化锆牙齿托槽及其制备方法 |
EP3088373A1 (en) | 2013-12-24 | 2016-11-02 | Tosoh Corporation | Translucent zirconia sintered body and zirconia powder, and use therefor |
JP2018052806A (ja) * | 2016-09-21 | 2018-04-05 | 東ソー株式会社 | ジルコニア焼結体及びその製造方法 |
WO2019026809A1 (ja) | 2017-07-31 | 2019-02-07 | クラレノリタケデンタル株式会社 | 蛍光剤を含むジルコニア焼結体 |
KR20190047701A (ko) | 2016-09-20 | 2019-05-08 | 쿠라레 노리타케 덴탈 가부시키가이샤 | 지르코니아 조성물, 가소체 및 소결체, 그리고 그들의 제조 방법 |
WO2019180766A1 (ja) * | 2018-03-19 | 2019-09-26 | 東ソー株式会社 | ジルコニア焼結体及びその製造方法 |
JP2020001973A (ja) * | 2018-06-28 | 2020-01-09 | クラレノリタケデンタル株式会社 | ジルコニア成形体の製造方法 |
KR20200022348A (ko) | 2018-08-22 | 2020-03-03 | 소후 인코포레이티드 | 치과 절삭 가공용 지르코니아 피절삭체 및 그 제조 방법 |
KR20200090640A (ko) | 2019-01-21 | 2020-07-29 | 소후 인코포레이티드 | 고속 소결 대응 고투과 지르코니아 블랭크 |
WO2022168734A1 (ja) * | 2021-02-03 | 2022-08-11 | 国立大学法人 東京大学 | カバー部材 |
Families Citing this family (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2045222B1 (en) | 2006-07-25 | 2015-09-23 | Tosoh Corporation | Sintered zirconia having high light transmission and high strength, use of the same and process for production thereof |
JP6416247B2 (ja) | 2013-06-27 | 2018-10-31 | イフォクレール ビバデント, インコーポレイテッド | ナノ結晶ジルコニアおよびその加工方法 |
US9962247B2 (en) | 2014-06-23 | 2018-05-08 | Tosoh Corporation | Colored translucent zirconia sintered body and powder, and application thereof |
EP3108849B1 (en) | 2016-04-25 | 2019-04-24 | 3M Innovative Properties Company | Multi-layered zirconia dental mill blank and process of production |
JP6962657B2 (ja) * | 2016-11-07 | 2021-11-05 | 株式会社松風 | 高い相対密度を有する多層の歯科用ジルコニアブランク |
KR20240025068A (ko) * | 2017-02-21 | 2024-02-26 | 소후 인코포레이티드 | 치과 절삭 가공용 지르코니아 피절삭체와 그 제조 방법 및 치과 절삭 가공용 지르코니아 피절삭체용 투명성 향상액과 그 사용 방법 |
DE102018103906A1 (de) | 2017-02-22 | 2018-08-23 | James R. Glidewell Dental Ceramics, Inc. | Hochfeste und transluzente Dentalkeramikmaterialien, -einrichtungen und -verfahren |
WO2018168666A1 (ja) * | 2017-03-13 | 2018-09-20 | Agc株式会社 | 透光性セラミックス焼結体とその製造方法 |
US11802237B2 (en) | 2017-07-31 | 2023-10-31 | Kuraray Noritake Dental Inc. | Method for producing powder containing zirconia particles and fluorescent agent |
EP3663264A4 (en) * | 2017-07-31 | 2021-04-21 | Kuraray Noritake Dental Inc. | PROCESS FOR MANUFACTURING POWDER CONTAINING ZIRCONIA PARTICLES |
WO2019166938A1 (en) * | 2018-02-28 | 2019-09-06 | 3M Innovative Properties Company | Process for producing a dental zirconia article with a fast sintering process |
JP2019163246A (ja) | 2018-03-20 | 2019-09-26 | 株式会社松風 | イットリア含有量の異なる多層構造ジルコニア |
US11161789B2 (en) * | 2018-08-22 | 2021-11-02 | James R. Glidewell Dental Ceramics, Inc. | Highly translucent zirconia material, device, methods of making the same, and use thereof |
JP7336507B2 (ja) * | 2019-03-06 | 2023-08-31 | クラレノリタケデンタル株式会社 | 短時間で焼成可能なジルコニア成形体および仮焼体 |
US20220259063A1 (en) * | 2019-05-22 | 2022-08-18 | Nippon Shokubai Co., Ltd. | Zirconium oxide nanoparticles, dispersion liquid and resin composition |
CN110240491B (zh) * | 2019-07-09 | 2021-11-23 | 成都贝施美生物科技有限公司 | 一种高韧性的氧化锆瓷块 |
CN112624761B (zh) | 2019-10-08 | 2024-04-30 | 东曹株式会社 | 氧化锆烧结体及其制造方法 |
JPWO2021075564A1 (ja) * | 2019-10-17 | 2021-04-22 | ||
FR3103190B1 (fr) | 2019-11-14 | 2021-12-03 | Saint Gobain Ct Recherches | Article dentaire, poudre pour article dentaire et procede de fabrication d’un tel article |
WO2021100876A1 (ja) * | 2019-11-22 | 2021-05-27 | クラレノリタケデンタル株式会社 | ジルコニア組成物、ジルコニア仮焼体及びジルコニア焼結体、並びにそれらの製造方法 |
JPWO2022138760A1 (ja) | 2020-12-22 | 2022-06-30 | ||
EP4269354A1 (en) * | 2020-12-24 | 2023-11-01 | Kuraray Noritake Dental Inc. | Zirconia pre-sintered body |
WO2023042893A1 (ja) | 2021-09-16 | 2023-03-23 | 東ソー株式会社 | 粉末組成物、仮焼体、焼結体及びその製造方法 |
WO2023127793A1 (ja) * | 2021-12-27 | 2023-07-06 | クラレノリタケデンタル株式会社 | ジルコニア焼結体及びその製造方法 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62153163A (ja) | 1985-09-06 | 1987-07-08 | 東レ株式会社 | ジルコニア焼結体 |
WO2008013099A1 (fr) * | 2006-07-25 | 2008-01-31 | Tosoh Corporation | Zircone frittée ayant une transmission de lumière élevée et une résistance élevée, son utilisation et son procédé de fabrication |
JP2008081325A (ja) * | 2006-09-25 | 2008-04-10 | Tosoh Corp | ジルコニア微粉末及びその製造方法 |
JP2008222450A (ja) | 2007-03-08 | 2008-09-25 | Tosoh Corp | 透光性イットリア含有ジルコニア焼結体及びその製造方法並びにその用途 |
WO2009125793A1 (ja) | 2008-04-09 | 2009-10-15 | 東ソー株式会社 | 透光性ジルコニア焼結体及びその製造方法並びにその用途 |
Family Cites Families (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3432314A (en) * | 1966-08-02 | 1969-03-11 | Us Air Force | Transparent zirconia composition and process for making same |
EP0218853B1 (en) * | 1985-09-06 | 1994-11-09 | Toray Industries, Inc. | Method for manufacturing a sintered zirconia material |
JPH01113038A (ja) * | 1987-07-02 | 1989-05-01 | Tosoh Corp | 歯列矯正ブラケット |
JP2571646B2 (ja) | 1991-03-06 | 1997-01-16 | ホーヤ株式会社 | 象牙色ジルコニア焼結体及びその用途 |
US5326518A (en) * | 1991-10-08 | 1994-07-05 | Nissan Chemical Industries, Ltd. | Preparation of sintered zirconia body |
US6087285A (en) * | 1997-10-13 | 2000-07-11 | Tosoh Corporation | Zirconia sintered body, process for production thereof, and application thereof |
US7655586B1 (en) * | 2003-05-29 | 2010-02-02 | Pentron Ceramics, Inc. | Dental restorations using nanocrystalline materials and methods of manufacture |
JP5277541B2 (ja) * | 2006-07-25 | 2013-08-28 | 東ソー株式会社 | 高強度ジルコニア焼結体および製造方法 |
JP5018142B2 (ja) | 2007-03-07 | 2012-09-05 | 東ソー株式会社 | 透光性ジルコニア焼結体及びその製造方法 |
JP5608976B2 (ja) * | 2008-12-24 | 2014-10-22 | 東ソー株式会社 | 透光性ジルコニア焼結体及びその製造方法並びに用途 |
EP2463257B1 (en) * | 2009-08-07 | 2018-06-06 | Tosoh Corporation | Transparent zirconia sintered body and method for producing same |
JP2011073907A (ja) * | 2009-09-29 | 2011-04-14 | World Lab:Kk | ジルコニア焼結体及びその製造方法 |
JP5861397B2 (ja) * | 2010-11-11 | 2016-02-16 | 東ソー株式会社 | 着色透光性ジルコニア焼結体及びその製造方法並びにその用途 |
EP2500009A1 (en) | 2011-03-17 | 2012-09-19 | 3M Innovative Properties Company | Dental ceramic article, process of production and use thereof |
WO2013018728A1 (ja) * | 2011-07-29 | 2013-02-07 | 東ソー株式会社 | 着色透光性ジルコニア焼結体及びその用途 |
CN102875147B (zh) * | 2012-10-17 | 2013-11-20 | 安泰科技股份有限公司 | 氧化锆陶瓷材料及其制备方法 |
KR102595006B1 (ko) | 2013-12-24 | 2023-10-27 | 토소가부시키가이샤 | 투광성 지르코니아 소결체 및 지르코니아 분말, 그리고 그의 용도 |
US9962247B2 (en) | 2014-06-23 | 2018-05-08 | Tosoh Corporation | Colored translucent zirconia sintered body and powder, and application thereof |
-
2014
- 2014-12-19 KR KR1020167010902A patent/KR102595006B1/ko active IP Right Grant
- 2014-12-19 US US15/104,036 patent/US9737383B2/en active Active
- 2014-12-19 KR KR1020237029372A patent/KR20230129196A/ko not_active Application Discontinuation
- 2014-12-19 CN CN202110376123.5A patent/CN113185284B/zh active Active
- 2014-12-19 WO PCT/JP2014/083763 patent/WO2015098765A1/ja active Application Filing
- 2014-12-19 EP EP14874020.2A patent/EP3088373B1/en active Active
- 2014-12-19 CN CN201480069715.0A patent/CN105829264B/zh active Active
- 2014-12-22 JP JP2014258804A patent/JP6543926B2/ja active Active
-
2019
- 2019-06-18 JP JP2019113116A patent/JP6760443B2/ja active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62153163A (ja) | 1985-09-06 | 1987-07-08 | 東レ株式会社 | ジルコニア焼結体 |
WO2008013099A1 (fr) * | 2006-07-25 | 2008-01-31 | Tosoh Corporation | Zircone frittée ayant une transmission de lumière élevée et une résistance élevée, son utilisation et son procédé de fabrication |
JP2008081325A (ja) * | 2006-09-25 | 2008-04-10 | Tosoh Corp | ジルコニア微粉末及びその製造方法 |
JP2008222450A (ja) | 2007-03-08 | 2008-09-25 | Tosoh Corp | 透光性イットリア含有ジルコニア焼結体及びその製造方法並びにその用途 |
WO2009125793A1 (ja) | 2008-04-09 | 2009-10-15 | 東ソー株式会社 | 透光性ジルコニア焼結体及びその製造方法並びにその用途 |
Non-Patent Citations (3)
Title |
---|
"Lattice Parameters and Density for Y 0 -Stabilized Zr0", J. AM. CERAM. SOC., vol. 69, no. 4, 1986, pages 325 - 32 |
"Trabsparent Nanometric Cubic and Tetragonal Zirconia Obtained by High-Pressure Electric Current Sintering", ADV. FUNCT. MATER., vol. 17, 2007, pages 3267 - 3273 |
CHOJIRO MASUDA: "Understanding Zirconia and Comprehensively Applying It to a Wide Dental Practice -Zairyo o Ikani Ikashite Hotetsu Sochi o Tsukuriageruka", ANNALS OF JAPAN PROSTHODONTIC SOCIETY, vol. 4, no. 2, April 2012 (2012-04-01), pages 148 - 154, XP055355419 * |
Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3088373A1 (en) | 2013-12-24 | 2016-11-02 | Tosoh Corporation | Translucent zirconia sintered body and zirconia powder, and use therefor |
CN105997275B (zh) * | 2016-06-26 | 2019-05-14 | 江苏思麦尔生命科技有限公司 | 一种透明氧化锆托槽的制备方法 |
CN105997275A (zh) * | 2016-06-26 | 2016-10-12 | 江苏思麦尔生命科技有限公司 | 一种便于拆卸的透明氧化锆牙齿托槽及其制备方法 |
US11535564B2 (en) | 2016-09-20 | 2022-12-27 | Kuraray Noritake Dental Inc. | Zirconia composition, pre-sintered body and sintered body, and method of producing the same |
KR20190047701A (ko) | 2016-09-20 | 2019-05-08 | 쿠라레 노리타케 덴탈 가부시키가이샤 | 지르코니아 조성물, 가소체 및 소결체, 그리고 그들의 제조 방법 |
US11884595B2 (en) | 2016-09-20 | 2024-01-30 | Kuraray Noritake Dental Inc. | Zirconia composition, pre-sintered body and sintered body, and method of producing the same |
US11873254B2 (en) | 2016-09-20 | 2024-01-16 | Kuraray Noritake Dental Inc. | Zirconia composition, pre-sintered body and sintered body, and method of producing the same |
KR20220150438A (ko) | 2016-09-20 | 2022-11-10 | 쿠라레 노리타케 덴탈 가부시키가이샤 | 지르코니아 조성물, 가소체 및 소결체, 그리고 그들의 제조 방법 |
JP2018052806A (ja) * | 2016-09-21 | 2018-04-05 | 東ソー株式会社 | ジルコニア焼結体及びその製造方法 |
JP7077552B2 (ja) | 2016-09-21 | 2022-05-31 | 東ソー株式会社 | ジルコニア焼結体及びその製造方法 |
WO2019026809A1 (ja) | 2017-07-31 | 2019-02-07 | クラレノリタケデンタル株式会社 | 蛍光剤を含むジルコニア焼結体 |
KR20200035277A (ko) | 2017-07-31 | 2020-04-02 | 쿠라레 노리타케 덴탈 가부시키가이샤 | 형광제를 포함하는 지르코니아 소결체 |
US11401461B2 (en) | 2017-07-31 | 2022-08-02 | Kuraray Noritake Dental Inc. | Zirconia sintered body containing fluorescent agent |
WO2019180766A1 (ja) * | 2018-03-19 | 2019-09-26 | 東ソー株式会社 | ジルコニア焼結体及びその製造方法 |
US11021401B2 (en) | 2018-03-19 | 2021-06-01 | Tosoh Corporation | Zirconia sintered body and method for manufacturing the same |
US11746054B2 (en) | 2018-03-19 | 2023-09-05 | Tosoh Corporation | Zirconia sintered body and method for manufacturing the same |
JP7061827B2 (ja) | 2018-06-28 | 2022-05-02 | クラレノリタケデンタル株式会社 | ジルコニア成形体の製造方法 |
JP2020001973A (ja) * | 2018-06-28 | 2020-01-09 | クラレノリタケデンタル株式会社 | ジルコニア成形体の製造方法 |
EP3636621A2 (en) | 2018-08-22 | 2020-04-15 | Shofu Inc. | Zirconia mill blank for dental cutting and machining and preparing method thereof |
KR20200022348A (ko) | 2018-08-22 | 2020-03-03 | 소후 인코포레이티드 | 치과 절삭 가공용 지르코니아 피절삭체 및 그 제조 방법 |
US11986362B2 (en) | 2018-08-22 | 2024-05-21 | Shofu Inc. | Zirconia mill blank for dental cutting and machining and preparing method thereof |
EP3712121A1 (en) | 2019-01-21 | 2020-09-23 | Shofu Inc. | High permeable zirconia blank capable of sintering at high speed |
KR20200090640A (ko) | 2019-01-21 | 2020-07-29 | 소후 인코포레이티드 | 고속 소결 대응 고투과 지르코니아 블랭크 |
WO2022168734A1 (ja) * | 2021-02-03 | 2022-08-11 | 国立大学法人 東京大学 | カバー部材 |
Also Published As
Publication number | Publication date |
---|---|
CN113185284A (zh) | 2021-07-30 |
JP6543926B2 (ja) | 2019-07-17 |
KR20230129196A (ko) | 2023-09-06 |
JP6760443B2 (ja) | 2020-09-23 |
EP3088373A1 (en) | 2016-11-02 |
CN113185284B (zh) | 2022-09-23 |
JP2015143178A (ja) | 2015-08-06 |
EP3088373B1 (en) | 2019-11-27 |
CN105829264B (zh) | 2021-04-23 |
KR20160100914A (ko) | 2016-08-24 |
EP3088373A4 (en) | 2017-08-02 |
KR102595006B1 (ko) | 2023-10-27 |
US20160310245A1 (en) | 2016-10-27 |
CN105829264A (zh) | 2016-08-03 |
US9737383B2 (en) | 2017-08-22 |
JP2019189524A (ja) | 2019-10-31 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6760443B2 (ja) | 透光性ジルコニア焼結体及びジルコニア粉末、並びにその用途 | |
US10555795B2 (en) | Colored translucent zirconia sintered body and powder, and use thereof | |
KR101906628B1 (ko) | 착색 투광성 지르코니아 소결체 및 그의 용도 | |
CA2719340C (en) | Translucent zirconia sintered body, process for producing the same, and use of the same | |
JP5608976B2 (ja) | 透光性ジルコニア焼結体及びその製造方法並びに用途 | |
JP2023138969A (ja) | ジルコニア焼結体及びその製造方法 | |
JP2009269812A (ja) | 透光性ジルコニア焼結体及びその製造方法並びに用途 | |
JP5707667B2 (ja) | 透光性ジルコニア焼結体及びその製造方法及びその用途 | |
JP5748012B2 (ja) | 透光性ジルコニア焼結体及びその製造方法及びその用途 | |
JP5804144B2 (ja) | 透光性ジルコニア焼結体及びその用途 | |
JP2016500362A (ja) | セラミック材料 | |
JP5741735B2 (ja) | 透光性ジルコニア焼結体用粉末 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 14874020 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 20167010902 Country of ref document: KR Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 15104036 Country of ref document: US |
|
REEP | Request for entry into the european phase |
Ref document number: 2014874020 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2014874020 Country of ref document: EP |
|
NENP | Non-entry into the national phase |
Ref country code: DE |