Zirconia layered body
Provided is at least any of a layered body, which has a change in texture derived from zirconia, particularly a change in translucency and is suitable as a dental prosthetic member, a precursor thereof, or a method for producing these. There is provided a layered body having a structure in which two or more layers containing zirconia containing a stabilizer are layered, the layered body including at least: a first layer containing zirconia having a stabilizer content of higher than or equal to 4 mol %; and a second layer containing zirconia having a stabilizer content different from that of the zirconia contained in the first layer.
1. A layered body having a structure in which two or more layers containing zirconia containing a stabilizer are layered, the layered body comprising at least:
a first layer containing zirconia having a stabilizer content of higher than or equal to 4 mol %; and
a second layer containing zirconia having a stabilizer content different from that of the zirconia contained in the first layer, wherein a difference between the stabilizer content in the first layer and the stabilizer content in the second layer is greater than or equal to 0.5 mol %, and the layered body is a calcined body.
2. The layered body according to claim 1 ,
wherein the content of the stabilizer of the stabilizer-containing zirconia contained in the second layer is 1.5 mol % to 7.0 mol %.
3. The layered body according to claim 1 ,
wherein the content of the stabilizer of the stabilizer-containing zirconia contained in the second layer is 5.0 mol % to 7.0 mol %.
4. The layered body according to claim 1 ,
wherein the content of the stabilizer of the stabilizer-containing zirconia contained in the first layer is 4.0 mol % to 6.0 mol %.
5. The layered body according to claim 1 ,
wherein the stabilizer is one or more selected from the group consisting of yttria (Y 2 O 3 ), calcia (CaO), magnesia (MgO), and ceria (CeO 2 ).
6. The layered body according to claim 1 ,
wherein at least one of the layers contains alumina.
7. The layered body according to claim 1 ,
wherein a warp measured using a thickness gauge according to JIS B 7524:2008 is less than or equal to 1.0 mm.
8. The layered body according to claim 1 ,
wherein a warp measured using a thickness gauge according to JIS B 7524:2008 is less than or equal to 0.2 mm.
9. The layered body according to claim 1 ,
wherein a density is 2.4 g/cm 3 to 3.7 g/cm 3 .
10. A method for producing the layered body according to claim 1 , comprising:
calcining a green body at 800° C. to 1,200° C.,
wherein the green body has a structure, in which two or more powder composition layers consisting of a powder composition containing stabilizer-containing zirconia and a binding agent are layered, includes at least
a first powder composition layer containing a binding agent and zirconia which has a stabilizer content of higher than or equal to 4 mol % and
a second powder composition layer containing a binding agent and zirconia which has a stabilizer content different from that of the zirconia contained in the first powder composition layer, and
has a difference in a binder content between the first powder composition layer and the second powder composition layer which exceeds 0.01 wt %.
11. A method for producing the layered body according to claim 1 , the method comprising:
calcining a green body at a temperature of higher than or equal to 800° C. and lower than 1,200° C. to obtain a calcined body; and
wherein the green body has a structure, in which two or more powder composition layers consisting of a powder composition containing stabilizer-containing zirconia and a binding agent are layered, includes at least
a first powder composition layer containing a binding agent and zirconia which has a stabilizer content of higher than or equal to 4 mol % and
a second powder composition layer containing a binding agent and zirconia which has a stabilizer content different from that of the zirconia contained in the first powder composition layer, and
has a difference in a binding agent content between the first powder composition layer and the second powder composition layer which exceeds 0.01 wt %.
12. A method for producing the layered body according to claim 1 comprising:
calcining a green body at a temperature of higher than or equal to 900° C. and lower than 1,150° C.,
wherein the green body has a structure, in which two or more powder composition layers consisting of a powder composition containing stabilizer-containing zirconia and a binding agent are layered, includes at least
a first powder composition layer containing a binding agent and zirconia which has a stabilizer content of higher than or equal to 4 mol % and
a second powder composition layer containing a binding agent and zirconia which has a stabilizer content different from that of the zirconia contained in the first powder composition layer, and
has a difference in a binding agent content between the first powder composition layer and the second powder composition layer which exceeds 0.01 wt %.
13. The production method according to claim 12 ,
wherein a warp of the green body measured using a thickness gauge according to JIS B 7524:2008 is less than or equal to 1.0 mm.
14. The production method according to claim 12 ,
wherein the binding agent is one or more selected from the group consisting of polyvinyl alcohol, polyvinyl butyrate, wax, and acrylic resin.
15. The production method according to claim 12 ,
wherein the powder composition contained in the powder composition layers is granulated powder.
16. The production method according to claim 12 ,
wherein a density of the green body is 2.4 g/cm 3 to 3.7 g/cm 3 .
17. A dental material containing the layered body according to claim 1 .
18. A method for producing a sintered body, the method including sintering the calcined body according to claim 1 at 1,200° C. to 1,600° C.