JP6301176B2 - Glass ceramic composition and glass ceramic sintered body - Google Patents

Description

  The present invention relates to a glass ceramic composition and a glass ceramic sintered body. In particular, the present invention relates to a glass ceramic composition containing a cristobalite crystal and a glass ceramic sintered body.

  Different glass ceramic materials are used for different applications.

For example, Patent Document 1 discloses that aluminosilicate glass is used as a composition for adjusting the color tone of a ceramic dental crown material. The aluminosilicate glass described in Patent Document 1 has the following components: SiO ₂ 55.0 to 75.0 wt%, B ₂ O ₃ 5.0 to 20.0 wt%, Al ₂ O ₃ 5.0 to 15 .0 _wt%, Li 2 _{O0.5~1.5 wt%,} Na 2 _{O3.0~8.0 wt%,} K 2 _O3.0~8.0 wt%, CaO1.0～5.0 wt% , MgO 0.1 to 1.0 wt%, Sb ₂ O ₃ 0.1 to 1.0 wt%, firing temperature is 760 to 860 ° C., and linear thermal expansion coefficient in the range of 25 to 500 ° C. Is 6.0 × 10 ⁻⁶ K ^{−1 to} 9.0 × 10 ⁻⁶ K ⁻¹ .

  Patent Document 2 discloses a cristobalite crystal phase-containing silica glass having a high thermal expansion coefficient. The cristobalite crystal phase-containing silica glass described in Patent Document 2 is a cristobalite crystal phase-containing silica glass in which a spherical or island-like α-cristobalite crystal phase is present in the silica glass matrix phase, and the α-cristobalite crystal phase has a diameter of 0.1 to 1000 μm, and its content is at least 10% by weight.

JP 2009-207743 A JP-A-8-295534

  The following analysis is given from the perspective of the present invention.

  In the production process or use process of the glass ceramic material, mechanical three-dimensional machining of the ceramic is performed by computer control. For example, in the dental field, based on the three-dimensional data of a patient's teeth, a glass ceramic material is machined by computer control to produce a prosthesis for use in dental treatment.

  According to machining by computer control, a precise ceramic workpiece can be easily obtained. However, a ceramic workpiece obtained by computer-controlled mechanical three-dimensional machining does not provide a ceramic workpiece that fully satisfies the needs, that is, a ceramic workpiece that does not require further treatment. For example, the outer shape and size of the ceramic workpiece may be different from the desired outer shape and size, or the desired color tone may not be reproduced with the ceramic workpiece alone. In this case, the external shape / dimension correction and the color tone correction may be performed by adding the same or different ceramic material to the ceramic workpiece as the base material. For example, in the dental field, when a ceramic workpiece obtained by machining is applied to a patient as it is, problems such as poor occlusion and insufficient interference with adjacent teeth may occur. In this case, another ceramic material (sometimes referred to as add-on porcelain) is placed on the ceramic workpiece to correct the outer shape and size. Moreover, it is difficult to reproduce a color tone like natural teeth with a glass ceramic alone. In this case, a ceramic material containing a colorant (sometimes referred to as a stain porcelain) is applied to a ceramic workpiece to reproduce a color tone similar to that of natural teeth.

  The adjustment as described above is performed by, for example, applying a liquid material in which a powder of a ceramic material as an adjustment material is dispersed in a solvent onto a base material and firing (sintering) the ceramic material on the base material. Is called. Therefore, the property of the adjusting material may be restricted with respect to the property of the base material. For example, if the thermal expansion coefficient of the adjusting material is too higher than the thermal expansion coefficient of the base material, a defect occurs in the adjusting material. Moreover, application | coating and baking of an adjustment material may be performed in multiple times. In this case, it is desirable that the thermal expansion coefficient of the adjusting material does not vary greatly even after firing multiple times.

  As the adjusting material as described above, a ceramic material containing a leucite crystal is often used. However, since leucite crystals have a large coefficient of thermal expansion, the base materials to which porcelain containing leucite crystals can be applied are limited. Therefore, as a ceramic material that can replace the leucite crystal, it is conceivable to apply a cristobalite crystal that is a crystal of the main component silica of silicate glass. However, the cristobalite crystal known so far expands greatly during the transformation from α-type to β-type at around 200 ° C. Therefore, when such a cristobalite crystal-containing ceramic material is used as the adjustment material, defects will occur in the adjustment material during firing in the same manner as the leucite crystal.

  The aluminosilicate glass described in Patent Document 1 is considered to be amorphous. Therefore, it is considered that the color tone adjusting composition for dental crown porcelain does not have sufficient toughness. In general, when glass is crystallized, the thermal expansion coefficient tends to increase. Therefore, even if the aluminosilicate glass described in Patent Document 1 can be crystallized, it is estimated that the thermal expansion coefficient is considerably increased.

  In the cristobalite crystal phase-containing silica glass described in Patent Document 2, since closed cells are dispersed, sufficient strength cannot be obtained. Further, for example, due to closed cells, high transparency suitable for dental porcelain cannot be ensured.

  Therefore, for example, a ceramic material that does not have the above problem is desired.

According to the 1st viewpoint of this invention, the glass-ceramic composition containing the glass phase containing a cristobalite crystal | crystallization is provided. The glass phase is 75 mol% to 83 mol% SiO ₂ component, 3 mol% to 5 mol% Al ₂ O ₃ component, 2 mol% to 10 mol% B ₂ O ₃ component, 2 mol% to ₃ mol% Li ₂ O component, 3 mol % 5 mol% of Na ₂ O component, 2mol% ~4mol% of _{K 2} O ingredient, CaO ingredient 0.01 mol% to 1 mol%, and ZnO components of 0.01 mol% 2 mol%, the.

According to the 2nd viewpoint of this invention, the glass-ceramic sintered compact containing the glass phase containing a cristobalite crystal is provided. The glass phase is 75 mol% to 83 mol% SiO ₂ component, 3 mol% to 5 mol% Al ₂ O ₃ component, 2 mol% to 10 mol% B ₂ O ₃ component, 2 mol% to ₃ mol% Li ₂ O component, 3 mol % 5 mol% of Na ₂ O component, 2mol% ~4mol% of _{K 2} O ingredient, CaO ingredient 0.01 mol% to 1 mol%, and ZnO components of 0.01 mol% 2 mol%, the.

  Even with a glass ceramic material containing cristobalite crystals, the coefficient of thermal expansion during transformation can be lowered, and fluctuations in the coefficient of thermal expansion during multiple firings can be reduced.

Graph plotting the ratio of the SiO ₂ component and _Al 2 _{O 3} component to the basic component in the Examples and Comparative Examples _{(R 2} O and RO). 4 is an electron micrograph of the glass ceramic sintered body of Example 4. FIG. FIG. 3 is a distribution diagram of oxygen (O) on the photographic surface of FIG. 2. FIG. 3 is a distribution diagram of silicon (Si) on the photograph surface of FIG. 2. The X-ray-diffraction pattern of the glass ceramic sintered compact of Example 2, Example 4, the comparative example 3, and the comparative example 9. FIG.

  Below, the preferable form of each said viewpoint is described.

According to a preferred form of the first aspect, the glass phase is 75 mol% to 78 mol% SiO ₂ component, 4 mol% to 5 mol% Al ₂ O ₃ component, 7 mol% to 9 mol% B ₂ O ₃ component, 2 mol. % 3 mol% of Li ₂ O component, 3 mol% 5 mol% of Na ₂ O component, 2 mol% 3 mol% of _{K 2} O component, CaO component of 0.4mol% ~0.5mol%, and 0.8 mol% -1 mol% ZnO component is contained.

According to a preferred embodiment of the first aspect, the ratio of the molar fraction of the Al ₂ O ₃ component to the molar fraction of the SiO ₂ component in the glass phase is 0.062 or less.

According to the preferred form of the first aspect, the value obtained by dividing the molar fraction of the SiO ₂ component by the sum of the molar fractions of the basic component in the glass phase is 8.44 or less.

According to the preferable form of the first aspect, the value obtained by dividing the molar fraction of the Al ₂ O ₃ component by the sum of the molar fractions of the basic component in the glass phase is 0.40 or more.

  According to the 3rd viewpoint of this invention, the glass-ceramic sintered compact which sintered the particle | grains of the glass-ceramic composition which concerns on a 1st viewpoint is provided.

  According to the preferable form of the third viewpoint, the sintering is performed by heating at 860 ° C. or lower.

According to a preferred embodiment of the second aspect, the glass phase contains a cristobalite crystal, and the glass phase is 75 mol% to 78 mol% SiO ₂ component, 4 mol% to 5 mol% Al ₂ O ₃ component, 7 mol% to 9 mol% of _B 2 _{O 3} component, 2 mol% 3 mol% of Li ₂ O component, 3 mol% 5 mol% of Na ₂ O component, 2 mol% 3 mol% of _{K 2} O component, 0.4mol% ~0.5mol % CaO component, and 0.8 mol% to 1 mol% ZnO component.

According to the preferred embodiments of the second and third viewpoints, the ratio of the molar fraction of the Al ₂ O ₃ component to the molar fraction of the SiO ₂ component in the glass phase is 0.062 or less.

According to the preferred embodiments of the second and third viewpoints, the value obtained by dividing the molar fraction of the SiO ₂ component by the sum of the molar fractions of the basic component in the glass phase is 8.44 or less.

According to the preferable form of the second and third viewpoints, the value obtained by dividing the molar fraction of the Al ₂ O ₃ component by the sum of the molar fractions of the basic component in the glass phase is 0.40 or more.

According to the preferable form of the second viewpoint and the third viewpoint, the thermal expansion coefficient measured according to JIST6526 is 11 × 10 ⁻⁶ K ⁻¹ or less.

According to the preferred forms of the second and third viewpoints described above, the first thermal expansion coefficient measured in accordance with JIST6526 for the first sample fired once under the sintering conditions and the firing four times under the sintering conditions. The difference (absolute value) from the second thermal expansion coefficient measured for the second sample according to JIST6526 is less than 0.6 × 10 ⁻⁶ K ⁻¹ .

  The glass ceramic composition and the glass ceramic sintered body of the present invention are glass ceramic materials (crystallized glass) containing crystallized glass of cristobalite crystals. The glass ceramic composition and the glass ceramic sintered body preferably have an α-cristobalite crystal as a main crystal phase at room temperature. The presence of cristobalite crystals can be confirmed by an X-ray diffraction (XRD) pattern. The glass ceramic composition and the glass ceramic sintered body may not be able to detect a crystal phase other than the cristobalite crystal by the XRD pattern.

Glass ceramic composition and the glass ceramic sintered compact, as a component constituting the glass phase, containing SiO ₂ component. In the glass ceramic composition and the glass ceramic sintered body, the SiO ₂ component is preferably 75 mol% or more with respect to the total number of moles of the components constituting the glass phase. In the glass ceramic composition and the sintered glass ceramic body, the SiO ₂ component is preferably 80 mol% or less, more preferably 78 mol% or less with respect to the total number of moles of components constituting the glass phase. Thereby, the glass ceramic composition and glass ceramic sintered compact of the property which are mentioned later can be obtained.

The glass ceramic composition and the glass ceramic sintered body contain an Al ₂ O ₃ component as a component constituting the glass phase. In the glass ceramic composition and the sintered glass ceramic body, the Al ₂ O ₃ component is preferably 3 mol% or more and more preferably 4 mol% or more with respect to the total number of moles of components constituting the glass phase. In the glass ceramic composition and the glass ceramic sintered body, the Al ₂ O ₃ component is preferably 5 mol% or less with respect to the total number of moles of the components constituting the glass phase. Thereby, the glass ceramic composition and glass ceramic sintered compact of the property which are mentioned later can be obtained.

In the glass-ceramic composition and the sintered glass-ceramic, the silica component and alumina component molar ratio (number of moles of Al ₂ O ₃ component / number of moles of SiO ₂ component) as components constituting the glass phase is 0.062 or less. Is preferable. When this ratio is larger than 0.062, it becomes difficult to generate and grow cristobalite crystals. That is, it becomes an amorphous material.

About the ratio of SiO ₂ component, when the composition of the glass ceramic composition and the glass ceramic sintered body is expressed by molar ratio, the number of moles of basic components (RO component + R ₂ O component) among the components constituting the glass phase. The ratio of the SiO ₂ component to the total amount of (the number of moles of the SiO ₂ component / (the total number of moles of the RO component + R ₂ O component)) is preferably 8.44 or less. The ratio of Al ₂ O ₃ component, when showing the composition of the glass ceramic composition and a glass ceramic sintered body in a molar ratio, Al ₂ O ₃ to the total amount of moles of the basic component (RO component + R 2 _O component) The component ratio (number of moles of Al ₂ O ₃ component / (number of moles of RO component + R ₂ O component)) is preferably 0.40 or more. In the above molar ratio, for the B ₂ O ₃ component, as shown in the examples below, it is excluded from the calculation because it is considered that the influence of the physical properties is small.

The content ratio of the SiO ₂ component and the Al ₂ O ₃ component in the glass ceramic composition and the glass ceramic sintered body is preferably included in a triangular region as shown in the examples described later. This triangular region has x as (number of moles of SiO ₂ component / (total number of moles of RO component + R ₂ O component)) and y as (number of moles of Al ₂ O ₃ component / (RO component + R ₂ O component). The number of moles)) can be expressed by the following formula. At this time, the vertices of the triangle are (x, y) = (6.45, 0.40), (8.44, 0.53), and (8.44, 0.40).

y ≦ 0.062x
y ≧ 0.40
x ≦ 8.44

By setting the content ratio of the SiO ₂ component and the Al ₂ O ₃ component in the glass ceramic composition and the glass ceramic sintered body in the above ranges, the thermal expansion coefficient when the cristobalite crystal is transformed can be reduced. For example, when the glass ceramic composition is applied to a dental preparation, the glass ceramic composition applied on the base material is fired (that is, a glass ceramic sintered body is produced on the base material). The occurrence of defects due to thermal expansion can be suppressed.

It is preferable that the glass ceramic composition and the glass ceramic sintered body further contain a B ₂ O ₃ component as a component constituting the glass phase. The B ₂ O ₃ component is preferably 2 mol% or more, preferably 6 mol% or more, and 7 mol based on the total number of moles of the components constituting the glass phase in the glass ceramic composition and the glass ceramic sintered body. % Or more is more preferable. In the glass ceramic composition and the sintered glass ceramic body, the B ₂ O ₃ component is preferably 10 mol% or less, and more preferably 9 mol% or less with respect to the total number of moles of components constituting the glass phase. Thereby, the glass ceramic composition and glass ceramic sintered compact of the property which are mentioned later can be obtained.

It is preferable that the glass ceramic composition and the glass ceramic sintered body further contain a Li ₂ O component as a component constituting the glass phase. In the glass ceramic composition and the glass ceramic sintered body, the Li ₂ O component is preferably 2 mol% or more with respect to the total number of moles of the components constituting the glass phase. The Li ₂ O component is preferably 3 mol% or less with respect to the total number of moles of the components constituting the glass phase in the glass ceramic composition and the glass ceramic sintered body. Thereby, the glass ceramic composition and glass ceramic sintered compact of the property which are mentioned later can be obtained.

It is preferable that the glass ceramic composition and the glass ceramic sintered body further contain a Na ₂ O component as a component constituting the glass phase. In the glass ceramic composition and the glass ceramic sintered body, the Na ₂ O component is preferably 3 mol% or more with respect to the total number of moles of the components constituting the glass phase. In the glass ceramic composition and the glass ceramic sintered body, the Na ₂ O component is preferably 5 mol% or less with respect to the total number of moles of the components constituting the glass phase. Thereby, the glass ceramic composition and glass ceramic sintered compact of the property which are mentioned later can be obtained.

It is preferable that the glass ceramic composition and the glass ceramic sintered body further contain a K ₂ O component as a component constituting the glass phase. In the glass ceramic composition and the glass ceramic sintered body, the K ₂ O component is preferably 2 mol% or more with respect to the total number of moles of the components constituting the glass phase. In the glass ceramic composition and the glass ceramic sintered body, the K ₂ O component is preferably 4 mol% or less and more preferably 3 mol% or less with respect to the total number of moles of components constituting the glass phase. Thereby, the glass ceramic composition and glass ceramic sintered compact of the property which are mentioned later can be obtained.

  It is preferable that the glass ceramic composition and the glass ceramic sintered body further contain a CaO component as a component constituting the glass phase. The CaO component is preferably 0.01 mol% or more and more preferably 0.4 mol% or more with respect to the total number of moles of components constituting the glass phase in the glass ceramic composition and the glass ceramic sintered body. . The CaO component is preferably 1 mol% or less and more preferably 0.5 mol% or less with respect to the total number of moles of the components constituting the glass phase in the glass ceramic composition and the glass ceramic sintered body. Thereby, the glass ceramic composition and glass ceramic sintered compact of the property which are mentioned later can be obtained.

  It is preferable that the glass ceramic composition and the glass ceramic sintered body further contain a ZnO component as a component constituting the glass phase. In the glass ceramic composition and the glass ceramic sintered body, the ZnO component is preferably 0.01 mol% or more and more preferably 0.8 mol% or more with respect to the total number of moles of the components constituting the glass phase. . In the glass ceramic composition and the sintered glass ceramic body, the ZnO component is preferably 2 mol% or less, and more preferably 1 mol% or less with respect to the total number of moles of components constituting the glass phase. Thereby, the glass ceramic composition and glass ceramic sintered compact of the property which are mentioned later can be obtained.

The glass-ceramic composition and the glass-ceramic sintered body have SiO ₂ component, Al ₂ O ₃ component, B ₂ O ₃ component, Li ₂ O component, Na ₂ O component, K ₂ O component as components constituting the glass phase. It is preferable that a CaO component and a ZnO component are contained. The glass-ceramic composition and the glass-ceramic sintered body can be substantially composed of these eight components. That is, in the composition of the glass ceramic composition and the glass ceramic sintered body, the total number of moles of the eight components is substantially 100 mol% (that is, the mole fraction). be able to. At this time, the content of each component is preferably in the range shown above. Incidentally, if the glass ceramic composition and a glass ceramic sintered body is composed of components of eight above, the basic component (RO component + _{R 2} O component), Li ₂ O component, Na ₂ O component, _{K 2} O ingredient , CaO component, and ZnO component.

The glass ceramic composition and the glass ceramic sintered body can also contain at least one of a pigment, a fluorescent pigment, and an opacifying agent (opacifier). The pigment can be added to such an extent that it does not affect the composition. At least one of the pigment, the fluorescent pigment, and the opacifying agent (opacifier) may not constitute the glass phase. Examples of the pigment or fluorescent pigment include P, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Y, Zr, Sn, Sb, Bi, Ce, Pr, Sm, Eu, Gd, Tb, and Er. An oxide of at least one element selected from the group can be used. As the opacifying agent, for example, at least one compound selected from the group of TiO ₂ , ZrO ₂ , ZrSiO ₄ , SnO ₂ and CeO ₂ can be used. The pigment, fluorescent pigment, and opacifying agent added to the glass ceramic composition and the glass ceramic sintered body may be one compound or a plurality of compounds.

In the composition of the glass ceramic composition and the glass ceramic sintered body, the contents of SiO ₂ component, Al ₂ O ₃ component, Na ₂ O component, K ₂ O component, and CaO component are measured by, for example, fluorescent X-ray analysis can do. Content of li 2 _O component, for example, can be measured by atomic absorption spectroscopy. The content rates of the B ₂ O ₃ component and the ZnO component can be measured, for example, by inductively coupled plasma (ICP) emission spectroscopy. Or the composition computed from the compounding ratio in the raw material of each component which comprises a glass ceramic composition and a glass ceramic sintered compact can be considered as a composition of a glass ceramic composition and a glass ceramic sintered compact. This is because, as described in Examples 2 and 5 described later, the composition of the glass ceramic composition and the sintered glass ceramic body and the composition of the substrate can be regarded as substantially the same.

  The particle size (d50) of the glass ceramic composition is preferably 30 μm or less, preferably 20 μm or less, and preferably 10 μm or less.

  The sinterable temperature of the powder of the glass ceramic composition is preferably less than 900 ° C, more preferably less than 890 ° C, more preferably 880 ° C or less, and further preferably 860 ° C or less. Thereby, for example, when the glass ceramic composition is used as a dental adjustment material and sintered on the base material, the base material can be prevented from being damaged. Further, deformation due to overheating can be suppressed. For example, the powder of the glass ceramic composition can be sintered at a firing temperature of 780 ° C. or higher, and further, can be sintered at a firing temperature of 840 ° C. or higher.

  The glass-ceramic sintered body of the present invention can be obtained by sintering particles of the glass-ceramic composition of the present invention. The numerical values relating to the thermal expansion coefficient, transmittance, bending strength, fracture toughness, and dissolution amount described below are numerical values relating to the glass ceramic sintered body. That is, it is a value relating to a sample piece of a glass ceramic sintered body produced by heating and sintering a glass ceramic composition (powder) to a predetermined size based on each measurement method.

When the glass-ceramic composition and the glass-ceramic sintered body of the present invention are used as materials for adjustment to other materials (base materials), it is preferable that they have a thermal expansion coefficient in a range close to that of the base material. In particular, when the glass ceramic composition and the glass ceramic sintered body of the present invention are used as dental porcelain, the thermal expansion coefficient of the glass ceramic sintered body during the α-β transformation of the cristobalite crystal is zirconia as a base material. It is preferable that the thermal expansion coefficient is the same as that of the base material such as ceramics, alumina ceramics, and mica ceramics. For example, the first thermal expansion coefficient of the glass ceramic sintered body of the present invention is preferably 11 × 10 ⁻⁶ K ⁻¹ or less, more preferably 9 × 10 ⁻⁶ K ⁻¹ or less, and 7 × 10. It is more preferably ⁻⁶ K ⁻¹ or less, more preferably 5.9 × 10 ⁻⁶ K ⁻¹ or less, and even more preferably 5.6 × 10 ⁻⁶ K ⁻¹ or less, 5.4 ×. More preferably, it is 10 ⁻⁶ K ⁻¹ or less. The first thermal expansion coefficient of the glass ceramic sintered body is preferably 5 × 10 ⁻⁶ K ⁻¹ or more. Thereby, even if it applies and heats a glass-ceramic composition to a base material, generation | occurrence | production of a defect can be suppressed.

  The thermal expansion coefficient is preferably measured according to JIST6526 (2012). Since the sample piece of the glass ceramic sintered body is produced by sintering, it is fired once before measuring the thermal expansion coefficient. In the present specification, this is referred to as “first thermal expansion coefficient”. In addition, a sample piece (ie, a glass ceramic sintered body) produced by sintering the glass ceramic composition is further fired under the same firing conditions as those used during sintering, and then cooled to room temperature, followed by a refiring (blank firing) step. The thermal expansion coefficient measured in accordance with JIST6526 (2012) for the sample pieces obtained by performing the above three times (that is, the sample pieces fired four times in total) is referred to as “second thermal expansion coefficient”.

The second thermal expansion coefficient of the glass ceramic sintered body of the present invention is preferably 11 × 10 ⁻⁶ K ⁻¹ or less, more preferably 9 × 10 ⁻⁶ K ⁻¹ or less, and 7 × 10 ^−6. It is more preferably K ⁻¹ or less, more preferably 6.5 × 10 ⁻⁶ K ⁻¹ or less, and even more preferably 6.2 × 10 ⁻⁶ K ⁻¹ or less, 5.9 × 10 ^−. More preferably, it is ⁶ K ⁻¹ or less, preferably 5.6 × 10 ⁻⁶ K ⁻¹ or less, and further preferably 5.5 × 10 ⁻⁶ K ⁻¹ or less. For example, when the glass ceramic composition and the glass ceramic sintered body of the present invention are used for a dental adjustment material, the occurrence of defects can be suppressed even if firing is repeated a plurality of times.

Moreover, in order to suppress generation | occurrence | production of the defect by multiple times of baking, it is preferable if the fluctuation | variation of the thermal expansion coefficient of a glass ceramic sintered compact is small also by multiple times of baking. Therefore, it is preferable that the difference between the second thermal expansion coefficient and the first thermal expansion coefficient is smaller. The absolute value of the difference between the second thermal expansion coefficient and the first thermal expansion coefficient is preferably less than 0.6 × 10 ⁻⁶ K ⁻¹ , more preferably 0.5 × 10 ⁻⁶ K ⁻¹ or less. 0.4 × 10 ⁻⁶ K ⁻¹ or less, more preferably 0.2 × 10 ⁻⁶ K ⁻¹ or less. In general, the second thermal expansion coefficient is higher than the first thermal expansion coefficient.

  The transmittance of the glass ceramic sintered body can be appropriately set according to the application. For example, when a glass ceramic composition and a glass ceramic sintered body are used as dental porcelain, the transmittance can be 0% when the base material is not visible. On the other hand, when it is desired to reproduce the enamel, the transmittance is preferably 15% or more, preferably 30% or more, more preferably 50% or more, more preferably 55% or more, 60% More preferably, the above is true. The transmittance is preferably measured according to ISO Visual (ISO5-2). When a pigment, a fluorescent pigment, and an opacifying agent (opacifier) are added to the sample piece, the transmittance need not be satisfied.

  The bending strength of the glass ceramic sintered body is preferably 50 MPa or more, more preferably 70 MPa or more, more preferably 80 MPa or more, more preferably 100 MPa or more, more preferably 110 MPa or more, and 120 MPa. More preferably, it is more preferably 130 MPa or more. For example, when a glass ceramic composition and a glass ceramic sintered body are used as dental porcelain, sufficient durability can be ensured. The bending strength is preferably measured according to JIST6526 (2012).

Fracture toughness of the glass ceramic sintered body is preferable to be 0.8MPam ^1/2 or more, more preferably ^{1MPam 1/2} or more, more preferably 1.2MPam ^1/2 or more, 1.4MPam ^{1 / 2} or more, more preferably 1.5 MPam ^1/2 or more, more preferably 1.6 MPam ^1/2 or more, and more preferably 1.7 MPam ^1/2 or more. More preferably, it is 8 MPam ^1/2 or more. For example, when a glass ceramic composition and a glass ceramic sintered body are used as dental porcelain, sufficient durability can be ensured. Fracture toughness is preferably measured according to JIS R1607 (2010).

Dissolving amount acids glass ceramic sintered body is preferable to be 100 [mu] g / cm ² or less, preferable to be 50 [mu] g / cm ² or less, more preferable to be 20 [mu] g / cm ² or less, is 10 [mu] g / cm ² or less And more preferably 5 μg / cm ² or less. For example, when using a glass ceramic composition and a glass ceramic sintered body as dental porcelain, it is for suppressing loss of the glass ceramic sintered body in the oral cavity. The amount of dissolution is preferably measured according to JIST6526 (2012).

  In the X-ray diffraction pattern by CuKα rays of the glass ceramic composition and the glass ceramic sintered body, it is preferable that a sharp peak of cristobalite crystals can be confirmed in the range of 2θ of 20 ° to 25 °.

  Next, an example of a method for producing a glass ceramic composition and a glass ceramic sintered body will be described.

  First, for example, oxides corresponding to the above-described components, which constitute the glass phase of the target glass ceramic composition and glass ceramic sintered body, are prepared. Next, after drying an oxide, it weighs according to a composition. Next, each oxide is mixed. Next, for example, the mixture is melted and then cooled to produce a cullet. Next, after pulverizing the cullet, the cullet is sieved to become particles having a predetermined particle size range. Next, the melt is heated at 800 ° C. to 1000 ° C. for 30 minutes to 60 minutes to precipitate cristobalite crystals. Thereby, the glass-ceramic composition which is crystallized glass can be obtained. Next, the powder of the glass ceramic composition may be sieved so as to be in a predetermined particle size range.

  When adjusting the color, fluorescence, transmittance, etc. of the glass-ceramic composition and the sintered glass-ceramic, add at least one of a pigment, a fluorescent pigment and an opaque agent to the glass-ceramic composition and mix them. Can do.

  Next, an example of a method for producing a glass ceramic sintered body will be described. The glass ceramic composition is mixed and slurried in a solvent such as alcohol or purified water, and if necessary, formed into a predetermined shape and size. Next, after drying a molded object, a molded object can be heated and a glass ceramic composition can be sintered. When the glass ceramic composition and the glass ceramic sintered body are used as a dental adjustment material, the sintering temperature is preferably less than 900 ° C. and less than 890 ° C. in order not to cause a problem in the base material. More preferably, it is 880 degrees C or less, More preferably, it is 860 degrees C or less.

  A glass ceramic composition and a glass ceramic sintered body were produced, and various physical properties were measured. First, each compound for producing | generating each oxide which comprises a glass phase was heated at 120 degreeC, and was dried. Next, each compound was weighed so that the composition of the oxide in the glass phase was as shown in Table 1, and the mixture was mixed using a ball mill. The unit of Table 1 is mol /%. Table 2 shows the component ratios determined from the compositions in Table 1.

  Next, the mixture was filled in a melting crucible and melted at 1500 ° C. in the atmosphere. After cooling the melt, it was culleted, and the cullet was further pulverized using a ball mill. Next, the pulverized product was passed through a # 200 mesh sieve and sieved. Next, the obtained powder was put in a container made of refractory ceramics and heat-treated at 860 ° C. for 60 minutes. Thereby, the glass ceramic composition was able to be obtained.

  Next, the obtained glass ceramic composition was pulverized with a ball mill and then sieved with # 200 mesh to produce a glass ceramic composition powder.

  The powder of the glass ceramic composition was mixed with purified water and slurried, and then molded into sample pieces for measuring various physical properties. After the molded body was dried, it was heated at the sintering temperature shown in Table 3 for 1 minute to produce a glass ceramic sintered body. The sintering temperature shown in Table 3 is an appropriate sintering temperature at which the glass ceramic composition powder reaches sintering. The proper sintering temperature is a state in which the surface of the fired body is slightly glossy (that is, a state that has resulted in sintering), and a state in which the shape before firing is maintained (that is, deformation occurs due to excessive firing). This is the temperature at which (not) is obtained. Table 3 shows the crystal system confirmed by the X-ray diffraction method of the glass ceramic sintered body.

  About the obtained glass ceramic sintered compact, according to the above-mentioned measuring method, the 1st thermal expansion coefficient, the 2nd thermal expansion coefficient, translucency, fracture toughness, bending strength, and melt | dissolution amount were measured. The measurement results are shown in Tables 4 and 5.

The ranges of each component of Examples 1 to 10 in Table 1 are as follows: SiO ₂ component 75.6 mol% to 82.5 mol%, Al ₂ O ₃ component 3.9 mol% to 4.8 mol%, B ₂ O ₃ component 3. 0mol% ~9.4mol%, Li ₂ O component 2.2% ~2.8%, Na ₂ O ingredient 3.6% ~4.4mol%, _{K 2} O component 2.4mol% ~3.0mol%, The CaO component was 0.4 mol% to 0.5 mol%, and the ZnO component was 0.8 mol% to 1.0 mol%. Table 2, the proportion of and the SiO ₂ component to the total of the ratio of the Examples 1 to 10, and _Al 2 _{O 3} component and SiO ₂ component, basic component _{(R 2} O and RO), basic component _{(R 2} The ratio of Al ₂ O ₃ component to the total of O and RO) and the ratio of B ₂ O ₃ component to the total of basic components (R ₂ O and RO) are shown. The basic components (R ₂ O and RO) in Examples 1 to 10 are a Li ₂ O component, a Na ₂ O component, a K ₂ O component, a CaO component, and a ZnO component.

FIG. 1 shows a graph plotted as the horizontal axis Al ₂ O ₃ / (R ₂ O + RO) and the vertical axis SiO ₂ / (R ₂ O + RO) shown in Table 2. In Examples 1 to 10, the presence of cristobalite crystals was confirmed, whereas the glass ceramic compositions obtained in Comparative Examples 1 to 4 and 10 were amorphous. This is presumably because the Al ₂ O ₃ component was large relative to the whole or the SiO ₂ component.

For Comparative Examples 5 to 9, cristobalite crystals were observed. However, the first thermal expansion coefficients of Examples 1 to 10 were 5.9 × 10 ⁻⁶ K ⁻¹ or less, whereas in Comparative Examples 5, 6, 8 and 9, 6.7 × 10 ^−6. It was higher than K- ¹ and Examples 1-10.

Moreover, as for the difference between the second thermal expansion coefficient and the first thermal expansion coefficient, the difference between Examples 1 to 10 was 0.5 × 10 ⁻⁶ K ⁻¹ or less, whereas in Comparative Examples 6 to 9. The variation was 0.6 × 10 ⁻⁶ K ⁻¹ or more, which was large compared to Examples 1-10.

  Therefore, according to the glass ceramic composition and the glass ceramic sintered body according to Examples 1 to 10, the first thermal expansion coefficient, the second thermal expansion coefficient, and the second coefficient are higher than those of the ceramic materials according to Comparative Examples 5 to 9. At least one of the differences between the thermal expansion coefficient and the first thermal expansion coefficient can be lowered. That is, according to Examples 1-10, the fluctuation | variation of the thermal expansion at the time of baking of a glass ceramic composition and a glass ceramic sintered compact, and the thermal expansion in multiple times baking can be suppressed. Thereby, it turns out that the glass-ceramic composition and glass-ceramic sintered compact of this invention are suitably applicable to a dental adjustment material, for example.

In FIG. 2, the electron micrograph of the glass-ceramic sintered compact of Example 4 is shown. The electron micrograph was measured at an acceleration voltage of 10 kV and a magnification of 10,000. FIG. 3 shows a distribution diagram of oxygen (O) on the photographic surface of FIG. FIG. 4 shows a distribution diagram of silicon (Si) on the photographic surface of FIG. From this, it was confirmed that the crystal grains observed in the photograph of FIG. 2 are not heterogeneous crystals containing Al or the like, that is, SiO ₂ crystals.

  In FIG. 5, the X-ray-diffraction pattern of the glass ceramic sintered compact of Example 2, Example 4, the comparative example 3, and the comparative example 9 is shown. The X-ray diffraction pattern was measured with CuKα rays (50 kV, 50 mA). From FIG. 5, it was identified that the crystal grains shown in FIGS. 2 to 4 are cristobalite crystals. As described above, the glass ceramic of Comparative Example 3 was amorphous. Moreover, it is estimated that the comparative example 9 with a high thermal expansion coefficient contains the cristobalite crystal | crystallization with higher crystallinity than the glass-ceramic sintered compact which concerns on Example 2 and 4. From this, it is presumed that the coefficient of thermal expansion and the variation of the coefficient of thermal expansion can be kept low by keeping the crystallinity of the cristobalite crystal within a certain range.

  Moreover, in Examples 1-10, although the appropriate sintering temperature was 860 degreeC or less, in Comparative Examples 5-7, the appropriate sintering temperature became 890 degreeC or more. That is, the proper sintering temperature in Comparative Examples 5-7 was higher than the proper sintering temperature in Examples 1-10. For example, when a glass ceramic composition and a glass ceramic sintered body are applied to a dental preparation, the glass ceramic composition is sintered on a substrate such as a mica ceramic material. Therefore, it is preferable that the firing temperature of the glass ceramic composition is low in order not to cause a problem in the base material and in order to prevent deformation of the adjusting material. Therefore, according to the glass-ceramic composition and glass-ceramic sintered body of this invention, it turns out that it can apply suitably, for example to a dental adjustment material.

Here, referring to FIG. 1, the compositions of Examples 1 to 10 have apexes (x, y) = (6.45, 0.40), (8.44, 0.52), and (8 .44, 0.40) are included in the triangular area. At this time, the SiO ₂ component and Al ₂ O ₃ component in the glass phase are (SiO ₂ , Al ₂ O ₃ ) = (75.4 mol%, 4.7 mol%), (79.2 mol%, 4.9 mol%). And (80.1 mol%, 3.8 mol%). The functions of the sides of the triangle are y ≦ 0.062x, y ≧ 0.40, and x ≦ 8.44, respectively. Thus, in order to obtain a glass ceramic composition and a glass ceramic sintered body having the crystallinity of cristobalite as described above, a low coefficient of thermal expansion, a small variation in the coefficient of thermal expansion, and a low sinterable temperature, the composition is It is presumed that the setting should be made so that it falls within the range of the triangle. Note that the composition range is not intended to be limited to a triangular region, and the region surrounded by the line may be changed or expanded by further addition of the examples.

  As for the glass-ceramic sintered body, favorable results were obtained with respect to translucency, fracture toughness, bending strength, and dissolution amount. From this, it was confirmed that the glass ceramic composition and glass ceramic sintered body of the present invention can be suitably applied to, for example, a dental adjustment material.

Elemental analysis was performed on the glass ceramic compositions obtained in Examples 2 and 5. For the SiO ₂ component, Al ₂ O ₃ component, Na ₂ O component, K ₂ O component, and CaO component, the measurement sample is made into a glass bead, and the calibration curve method is performed using a fluorescent X-ray analyzer (ZSX100e) manufactured by Rigaku Corporation. Measured. The li 2 _O component, a measurement sample was prepared and a solution of hydrofluoric acid was measured with Hitachi, Ltd. atomic absorption spectrophotometer (Z-5310). The B ₂ O ₃ component, a measurement sample was prepared a solution prepared by alkaline lysis was measured by SII Nano Technology Inc. ICP emission spectrophotometer (SPS3500). About the ZnO component, the solution which melt | dissolved the measurement sample in the hydrofluoric acid was produced, and it measured with the SII nanotechnology company make ICP emission-spectral-analysis apparatus (SPS3500). Table 6 shows the analysis results. The raw material composition in Table 6 is the same as the composition shown in Table 1. As a result of analysis, it was confirmed that the composition of the resultant product was consistent with the composition of the raw material. From this, it was confirmed that the composition of the glass ceramic composition and the glass ceramic sintered body can be represented by the composition of the raw materials and can be controlled by the blending of the raw materials.

  Each disclosure of the above patent document is incorporated herein by reference. The glass-ceramic composition, the glass-ceramic sintered body, and the manufacturing method thereof according to the present invention have been described based on the above-described embodiment, but are not limited to the above-described embodiment, Various modifications to various disclosed elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) based on the basic technical concept of the present invention, It goes without saying that changes and improvements can be included. Various combinations and replacements of various disclosed elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) within the scope of the entire disclosure of the present invention. Selection is possible.

  Further problems, objects, and developments of the present invention will become apparent from the entire disclosure of the present invention including the claims.

  Regarding numerical ranges described in this document, any numerical value or small range included in the range should be construed as being specifically described even if there is no specific description.

Claims (14)

Including a glass phase containing cristobalite crystals,
The glass phase is
75 mol% to 83 mol% of SiO ₂ component,
3 mol% to 5 mol% of Al ₂ O ₃ component,
2 mol% 10 mol% of _B 2 _{O 3} component,
Li ₂ O component of 2 mol% 3 mol%,
Na ₂ O component of 3 mol% 5 mol%,
_{K 2} O ingredient 2mol% ~4mol%,
0.01 mol% to 1 mol% CaO component, and 0.01 mol% to 2 mol% ZnO component,
A glass ceramic composition comprising: The glass phase is
75 mol% to 78 mol% of SiO ₂ component,
4 mol% to 5 mol% of Al ₂ O ₃ component,
7mol% ~9mol% of _B 2 _{O 3} component,
Li ₂ O component of 2 mol% 3 mol%,
Na ₂ O component of 3 mol% 5 mol%,
_{K 2} O component of 2 mol% 3 mol%,
0.4 mol% to 0.5 mol% CaO component, and 0.8 mol% to 1 mol% ZnO component,
The glass ceramic composition according to claim 1, comprising: Wherein the ratio of the _Al 2 _{O 3} component molar fraction of the SiO ₂ component molar fraction of the glass phase is 0.062 or less, the glass ceramic composition according to claim 1 or 2. The value obtained by dividing the molar fraction of the SiO ₂ component in the total sum of the mole fraction of the basic components in the glass phase is 8.44 or less, the glass ceramic composition according to any one of claims 1 to 3 . The glass ceramic according to any one of claims 1 to 4, wherein a value obtained by dividing the molar fraction of the Al ₂ O ₃ component by the sum of the molar fractions of the basic components in the glass phase is 0.40 or more. Composition.   The glass-ceramic sintered compact which sintered the particle | grains of the glass-ceramic composition as described in any one of Claims 1-5.   The glass-ceramic sintered body according to claim 6, which is sintered by heating at 860 ° C or lower. Including a glass phase containing cristobalite crystals,
The glass phase is
75 mol% to 83 mol% of SiO ₂ component,
3 mol% to 5 mol% of Al ₂ O ₃ component,
2 mol% 10 mol% of _B 2 _{O 3} component,
Li ₂ O component of 2 mol% 3 mol%,
Na ₂ O component of 3 mol% 5 mol%,
_{K 2} O ingredient 2mol% ~4mol%,
0.01 mol% to 1 mol% CaO component, and 0.01 mol% to 2 mol% ZnO component,
A glass-ceramic sintered body containing The glass phase is
75 mol% to 78 mol% of SiO ₂ component,
4 mol% to 5 mol% of Al ₂ O ₃ component,
7mol% ~9mol% of _B 2 _{O 3} component,
Li ₂ O component of 2 mol% 3 mol%,
Na ₂ O component of 3 mol% 5 mol%,
_{K 2} O component of 2 mol% 3 mol%,
0.4 mol% to 0.5 mol% CaO component, and 0.8 mol% to 1 mol% ZnO component,
The glass ceramic sintered body according to claim 8, comprising: The glass ceramic sintered body according to any one of claims 6 to 9, wherein a ratio of a mole fraction of the Al ₂ O ₃ component and a mole fraction of the SiO ₂ component in the glass phase is 0.062 or less. . The value obtained by dividing the molar fraction of the SiO ₂ component in the total sum of the mole fraction of the basic components in the glass phase is 8.44 or less, a glass ceramic sintered according to any of claims 6-10 body. Wherein is the sum of the mole fraction of the basic components in the glass phase Al ₂ O ₃ value obtained by dividing the molar fraction of component 0.40 or more, the glass ceramic according to any one of claims 6 to 11 Sintered body. Thermal expansion coefficient was measured according to JIST6526 is 11 × ¹⁰ -6 ^{K -1} or less, a glass ceramic sintered body according to any one of claims 6-12. First thermal expansion coefficient measured according to JIST6526 for the first sample fired once under the sintering conditions, and second measured according to JIST6526 for the second sample fired four times under the sintering conditions The glass ceramic sintered body according to any one of claims ^{6 to} 13, wherein a difference (absolute value) from a coefficient of thermal expansion is less than 0.6 x ^10-6 K- ¹ .