Fluorescence imparting coloring solution for dental ceramics

1. A solution for coloring and imparting fluorescence to a zirconia dental article, the solution comprising:

a solvent;

a coloring agent comprising metal ions selected from Tb, Er, Pr, Mn and combinations thereof;

a fluorescing agent comprising ions of Bi; and

the solution not comprising Fe ions in an amount above about 0.05 wt.-% with respect to the weight of the solution.

2. The solution of claim 1 , wherein the molar ratio of the ions of the fluorescing agent to the ions of the coloring agent is in a range from about 1:10 to about 1:2000.

3. The solution of claim 1 , wherein the solvent is selected from water, alcohols, ketones, glycols and combinations thereof.

4. The solution of claim 1 further comprising:

complexing agent(s);

thickening agent(s);

marker substance(s);

additive(s);

or combinations thereof.

5. The solution of claim 1 , wherein the solution has a pH value of 0 to 9, if the solution contains water; has a viscosity of 1 to 2,000 mPa*s at 23° C.; is transparent, or a combination thereof.

6. The solution of claim 1 further comprising the components in the following amounts:

solvent: from about 15 to about 99 wt.-% calculated with respect to the amount of the solution,

coloring agent comprising metal ions in an amount from about 0.05 to about 10 wt.-%, of metal ions in the coloring agent calculated with respect to the amount of the solution, and

fluorescing agent: from about 0.005 to about 3 wt.-%, calculated with respect to the amount of the solution.

7. The solution of claim 1 , wherein the solution does not include ions selected from Dy, Nd, Sm, Eu and combinations thereof in an amount above about 0.1 wt.-% with respect to the weight of the solution, insoluble particles selected from SiO2, TiO2, ZrO2 and combinations thereof, or both.

8. The solution of claim 1 comprising:

water as solvent in an amount of 20 to 95 wt.-% calculated with respect to the weight of the solution,

coloring agent comprising ions of Tb, Er, Mn or combinations thereof in an amount of 0.2 to 8 wt.-% of the total Tb, Er and Mn ions, calculated with respect to the weight of the solution, and

fluorescence agent comprising ions of Bi in an amount of 0.02 to 2 wt.-%, calculated with respect to the weight of the solution, and wherein

the solution has a pH value in the range of 0 to 9;

the solution has a viscosity in the range of 1 to 2,000 mPa*s at 23° C.;

the solution does not include Fe ions in an amount above 0.05 wt.-%; and

the solution does not include ions selected from Dy, Nd, Sm, Eu or combinations thereof in an amount above about 0.1 wt.-% calculated with respect to the weight of the solution.

9. A device comprising a reservoir and an opening, wherein the reservoir containing the solution as described in claim 1 .

10. A process of coloring a zirconia dental article, the process comprising:

providing a zirconia dental article, the zirconia dental article being porous;

treating the zirconia dental article with the solution described in claim 1 ; and

optionally heating the treated porous zirconia dental article until at least 99.5% of the theoretical density is achieved.

11. The process of claim 10 , wherein the zirconia dental article has the shape of a crown, bridge, inlay, onlay, veneer, facing, coping, crown and bridged framework, implant, abutment, orthodontic appliances, or dental milling block and parts thereof.

12. The process of claim 11 , wherein the zirconia dental article is prepared by heat treating a zirconia aerogel.

13. The process of claim 12 , wherein the zirconia dental article is characterized by the following features:

a) showing a N2 adsorption and desorption of type IV with a hysteresis loop of type H1 according to IUPAC classification in a p/p0 range of 0.70 to 0.95;

b) average connected pore diameter: from about 10 to about 100 nm; and

c) BET surface: from about 10 to about 200 m 2 /g.

14. A kit of parts comprising:

the solution of claim 1 ;

a zirconia dental article, wherein the zirconia dental article is porous

optionally application equipment, and

optionally an instruction for use.

15. A kit of parts comprising; a receptacle containing a coloring liquid (A) and a receptacle containing a fluorescence liquid (B),

wherein the coloring liquid (A) comprises a solvent and coloring agent comprising ions selected from Tb, Er, Pr, Mn and combinations thereof,

wherein the fluorescing liquid (B) comprises a solvent and fluorescing agent comprising ions of Bi, and

wherein the coloring liquid (A) and the fluorescing liquid (B), if mixed to form a mixture, does not comprise Fe ions in an amount above about 0.05 wt.-% with respect to the weight of the mixture.