Zirconia layered body

Patent metadata

Field	Value
Publication number	US-2020283341-A1
Application number	US-202016801756-A
Country	US
Kind code	A1
Filing date	Feb 26, 2020
Priority date	Mar 7, 2019
Publication date	Sep 10, 2020
Grant date	—

Abstract

There is provided at least any of a layered body which has a change in color tone and in which it is unnecessary to select a colorant and the content of the colorant in consideration of a difference in the sintering behavior between layers, a precursor thereof, or a method for producing these. Provided is a layered body which has a structure, in which two or more layers containing stabilizer-containing zirconia and a colorant are layered, and in which types and contents of the colorants contained in the layers are equal to each other, the layered body including at least: a first layer containing a colorant and zirconia which has a stabilizer content of higher than or equal to 3.3 mol %; and a second layer containing a colorant and zirconia which has a stabilizer content different from that of the zirconia contained in the first layer.

First claim

What is claimed is:

1 . A layered body which has a structure, in which two or more layers containing stabilizer-containing zirconia and a colorant are layered, and in which types and contents of the colorants contained in the layers are equal to each other, the layered body comprising at least:
a first layer containing a colorant and zirconia which has a stabilizer content of higher than or equal to 3.3 mol %; and a second layer containing a colorant and zirconia which has a stabilizer content different from that of the zirconia contained in the first layer.

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 4.5 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 3.3 mol % to 5.5 mol %.

5 . The layered body according to claim 1 ,
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 0.2 mol %.

6 . 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), ceria (CeO 2 ), praseodymium oxide (Pr 6 O 11 ), neodymium oxide (Nd 2 O 3 ), terbium oxide (Tb 4 O 7 ), erbium oxide (Er 2 O 3 ), and ytterbium oxide (Yb 2 O 3 ).

7 . The layered body according to claim 1 ,
wherein the colorant is at least any of a transition metal element or a lanthanoid-based rare earth element.

8 . The layered body according to claim 1 ,
wherein the content of the colorant is 0.01 wt % to 1.0 wt %.

9 . The layered body according to claim 1 ,
wherein at least one of the layers contains alumina.

10 . 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.

11 . 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.

12 . The layered body according to claim 1 ,
wherein the layered body is a sintered body.

13 . The layered body according to claim 1 , further comprising:
a zirconia layer of which a total light transmittance with respect to a CIE standard light source D65 at a sample thickness of 1.0 mm is 30% to 50%.

14 . The layered body according to claim 1 ,
wherein the layered body is a calcined body.

15 . A method for producing the layered body according to claim 1 , comprising:
a step of sintering a green body at 1,200° C. to 1,600° C., wherein the green body has a structure, in which two or more powder composition layers consisting of a powder composition containing a stabilizer-containing zirconia, a colorant, and a binding agent are layered, and in which types and contents of the colorants contained in the powder composition layers are equal to each other, includes at least a first powder composition layer containing a binding agent, a color pigment, and zirconia which has a stabilizer content of higher than or equal to 3.3 mol % and a second powder composition layer containing a binding agent, a colorant, 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 exceeds 0.01 wt %.

16 . A method for producing the layered body according to claim 1 , comprising:
a step of 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 a step of sintering the calcined body at 1,200° C. to 1,600° C., wherein the green body has a structure, in which two or more powder composition layers consisting of a powder composition containing a stabilizer-containing zirconia, a colorant, and a binding agent are layered, and in which types and contents of the colorants contained in the powder composition layers are equal to each other, includes at least a first powder composition layer containing a binding agent, a colorant, and zirconia which has a stabilizer content of higher than or equal to 3.3 mol % and a second powder composition layer containing a binding agent, a colorant, 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 exceeds 0.01 wt %.

17 . A method for producing the layered body according to claim 1 , comprising:
a step of calcining a green body at a temperature of higher than or equal to 800° C. and lower than 1,200° C., wherein the green body has a structure, in which two or more powder composition layers consisting of a powder composition containing a stabilizer-containing zirconia, a colorant, and a binding agent are layered, and in which types and contents of the colorants contained in the powder composition layers are equal to each other, includes at least a first powder composition layer containing a binding agent, a colorant, and zirconia which has a stabilizer content of higher than or equal to 3.3 mol % and a second powder composition layer containing a binding agent, a colorant, 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 exceeds 0.01 wt %.

18 . The production method according to claim 15 ,
wherein the binding agent is one or more selected from the group consisting of polyvinyl alcohol, polyvinyl butyrate, wax, and acrylic resin.

19 . The production method according to claim 15 ,
wherein the powder composition contained in the powder composition layers is granulated powder.

20 . A dental material containing the layered body according to claim 1 .

Assignees

• Tosoh Corp

Inventors

• Ushio Yuki
• Ito Yuuki
• Azechi Sho
• Fujisaki Hiroyuki

Classifications

• C04B2235/6567

  Treatment time · CPC title

• C04B2235/661

  Multi-step sintering · CPC title

• A61C13/0022 Primary

  Blanks or green, unfinished dental restoration parts · CPC title

• C04B35/634

  Polymers (C04B35/636 takes precedence) · CPC title

• C04B2235/72

  Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics · CPC title