Process for the production of a zirconia-based, coloured, in particular grey, article and a zirconia-based coloured decorative article obtained using this process

Patent metadata

Field	Value
Publication number	US-10059629-B2
Application number	US-201514883984-A
Country	US
Kind code	B2
Filing date	Oct 15, 2015
Priority date	Oct 22, 2014
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

A process for the production of a grey zirconia-based article wherein a first mixture includes a zirconia powder forming the base constituent, 4% to 15% by weight of at least one stabilizer selected from among the group of oxides including yttrium oxide, magnesium oxide and calcium oxide alone or in combination, 0.1% to 1% by weight of a vanadium oxide powder (V 2 O 5 ), 0.1% to 1% by weight of a chromium oxide powder (Cr 2 O 3 ) and 0.1% to 1% by weight of a silicon oxide powder (SiO 2 ); making a second mixture including the first mixture and a binder; making a granulated mixture by conducting a granulation of the second mixture; forming a blank by giving this second granulated mixture the shape of the desired article; sintering the blank in air for at least thirty minutes at a temperature in the range of between 1250° and 1550° C.

First claim

What is claimed is:

1. A process for producing a zirconia-based article, the method comprising:
a) making a first mixture comprising:
a zirconia powder as a base constituent,
4% to 15% by weight of at least one stabiliser selected from the group consisting of yttrium oxide, magnesium oxide, and calcium oxide,
0.1% to 1% by weight of a vanadium oxide powder (V 2 O 5 ),
0.1% to 1% by weight of a chromium oxide powder (Cr 2 O 3 ), and
0.1% to 1% by weight of a silicon oxide powder (SiO 2 );

b) making a second mixture comprising said first mixture and a binder;
c) making a granulated mixture by conducting a granulation of said second mixture;
d) forming a blank by giving the granulated mixture a desired shape of the article; and
e) sintering said blank in air for at least thirty minutes at a temperature ranging from 1250° to 1550° C. to obtain a grey zirconia-based article.

2. The process according to claim 1 , wherein the first mixture comprises:
0.4% to 0.7% by weight of the vanadium oxide powder (V 2 O 5 ),
0.2% to 0.3% by weight of the chromium oxide powder (Cr 2 O 3 ), and
0.2% to 0.3% by weight of the silicon oxide powder (SiO 2 ).

3. The process according to claim 1 , wherein the first mixture further comprises: 0.1% to 1% by weight of a manganese oxide powder (MnO 2 ).

4. The process according to claim 1 , wherein the first mixture further comprises: 0.1% to 5% by weight of an aluminium oxide powder (Al 2 O 3 ).

5. The process according to claim 1 , wherein the first mixture further comprises: 0.1% to 1% by weight of an iron oxide powder (Fe 2 O 3 ).

6. The process according to claim 1 , wherein the stabiliser is yttrium oxide.

7. The process according to claim 1 , further comprising:
polishing the article after said sintering e) to obtain a polished grey zirconia-based article.

8. The process according to claim 1 , wherein the binder is a polyvinyl alcohol.

9. The process according to claim 1 , wherein said making c) is performed by subjecting the second mixture to a screening to obtain particles that have a grain size of less than 200 μm.

10. The process according to claim 1 , wherein the obtained zirconia-based article is in a solid grey color.

11. The process according to claim 1 , wherein the first mixture further comprises: 0.2% to 0.3% by weight of a manganese oxide powder (MnO 2 ).

Assignees

• Comadur Sa

Inventors

• Actis-Datta Arnaud
• Cartier Damien

Classifications

• G04B37/225

  Non-metallic cases · CPC title

• C04B35/486

  Fine ceramics · CPC title

• C04B2235/3225

  Yttrium oxide or oxide-forming salts thereof · CPC title

• C04B2235/3239

  Vanadium oxides, vanadates or oxide forming salts thereof, e.g. magnesium vanadate · CPC title

• C04B2235/5436

  micrometer sized, i.e. from 1 to 100 micron · CPC title