Refractory materials

Patent metadata

Field	Value
Publication number	US-RE46072-E
Application number	US-201514628688-A
Country	US
Kind code	E1
Filing date	Feb 23, 2015
Priority date	Dec 30, 2004
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

Refractory materials are provided which contain P 2 O 5 /R 2 O 3 constituents, where R is Y, Sc, Er, Lu, Yb, Tm, Ho, Dy, Tb, Gd, or a combination thereof, and/or V 2 O 5 /R′ 2 O 3 constituents where R′ is Y, Sc, one or more rare earth elements, or a combination thereof. In certain embodiments, the refractory materials are xenotime-type materials and/or xenotime-stabilized zircon-type materials. The refractory materials can be used in the manufacture of glass and glass-ceramics. For example, the refractory materials, especially those that contain P 2 O 5 /R 2 O 3 constituents, can be used as forming structures (“isopipes”) in the fusion process for making flat sheets of glass such as the glass sheets used as substrates in the manufacture of flat panel displays.

First claim

What is claimed is:

1. Apparatus for producing a glass or a glass-ceramic, said apparatus comprising a refractory body having a surface adapted to contact the glass or the glass-ceramic when the glass or the glass-ceramic is in a molten state, the refractory body comprising a phase which, on an oxide basis, consists of:
(i) 2.5-13.0 mole percent P 2 O 5 (the first constituent);
(ii) 2.5-13.0 mole percent Y 2 O 3 , Sc 2 O 3 , Er 2 O 3 , Lu 2 O 3 , Yb 2 O 3 , Tm 2 O 3 , Ho 2 O 3 , Dy 2 O 3 , Tb 2 O 3 , Gd 2 O 3 , or a combination thereof (the second constituent); and
(iii) the remainder of the phase being ZrSiO 4 HfSiO 4 ThSiO 4 , or a combination thereof;
wherein:
(a) (i) and (ii) are in a dissolved state in (iii),
(b) the refractory body has a volume of at least 200 cubic centimeters, and
(c) the phase comprises at least 90 volume percent of the refractory body.

2. The apparatus of claim 1 wherein the refractory body is at least 50 volume percent of the apparatus.

3. The apparatus of claim 1 wherein the refractory body is the entire apparatus.

4. The apparatus of claim 1 wherein:
(i) the apparatus comprises a core and a coating on the core, said core and coating having different compositions;
(ii) the surface adapted to contact the molten glass or the molten glass-ceramic is a surface, or a portion of a surface, of the coating; and
(iii) the refractory body comprises at least a portion of the coating.

5. The apparatus of claim 1 wherein the surface adapted to contact the molten glass or the molten glass-ceramic directs a flow of the molten glass or the molten glass-ceramic.

6. The apparatus of claim 5 wherein the apparatus is a forming trough of a fusion process.

7. The apparatus of claim 6 wherein the refractory body is the entire trough.

8. The apparatus of claim 6 wherein the forming trough has a length sufficient to produce sheets of the glass or the glass-ceramic having a width of at least 2.5 meters.

9. The apparatus of claim 1 wherein the second constituent is Y 2 O 3 .

10. The apparatus of claim 9 wherein the first and second constituents substantially satisfy the compositional formula YPO 4 .

11. The apparatus of claim 1 wherein the remainder of the phase substantially satisfies the compositional formula ZrSiO 4 .

12. The apparatus of claim 1 wherein on an oxide basis, the phase has at least 5 mole percent of the first constituent and at least 5 mole percent of the second constituent.

13. The apparatus of claim 1 wherein on an oxide basis, the phase has 13 mole percent of the first constituent and 13 mole percent of the second constituent.

14. The apparatus of claim 1 wherein the first and second constituents substantially satisfy the compositional formula YPO 4 and the remainder of the phase substantially satisfies the compositional formula ZrSiO 4 .

15. A method for producing a glass or a glass-ceramic comprising:
(I) providing apparatus for producing the glass or the glass-ceramic, wherein:
(A) the apparatus comprises a refractory body having a surface adapted to contact the glass or the glass-ceramic when the glass or the glass-ceramic is in a molten state; and
(B) the refractory body comprises a phase which, on an oxide basis, consists of:
(i) 2.5-13.0 mole percent P 2 O 5 (the first constituent);
(ii) 2.5-13.0 mole percent Y 2 O 3 , Sc 2 O 3 , Er 2 O 3 , Lu 2 O 3 , Yb 2 O 3 , Tm 2 O 3 , Ho 2 O 3 , Dy 2 O 3 , Tb 2 O 3 , Gd 2 O 3 , or a combination thereof (the second constituent); and
(iii) the remainder of the phase being ZrSiO 4 HfSiO 4 ThSiO 4 , or a combination thereof;
wherein:
(a) (i) and (ii) are in a dissolved state in (iii),
(b) the refractory body has a volume of at least 200 cubic centimeters, and
(c) the phase comprises at least 90 volume percent of the refractory body; and

(II) contacting at least a portion of the surface with the glass or the glass-ceramic in a molten state.

16. The method of claim 15 wherein in step (II), the glass or glass-ceramic in a molten state has a temperature above 1280° C.

17. The method of claim 15 wherein the refractory body is the entire apparatus.

18. The method of claim 15 wherein the surface adapted to contact the molten glass or the molten glass-ceramic directs a flow of the molten glass or the molten glass-ceramic.

19. The method of claim 18 wherein the apparatus is a forming trough of a fusion process.

20. The method of claim 19 wherein the refractory body is the entire trough.

21. The method of claim 19 wherein the forming trough has a length sufficient to produce sheets of the glass or the glass-ceramic having a width of at least 2.5 meters.

22. The method of claim 15 wherein the second constituent is Y 2 O 3 .

23. The method of claim 22 wherein the first and second constituents substantially satisfy the compositional formula YPO 4 .

24. The method of claim 15 wherein the remainder of the phase substantially satisfies the compositional formula ZrSiO 4 .

25. The method of claim 15 wherein on an oxide basis, the phase has at least 5 mole percent of the first constituent and at least 5 mole percent of the second constituent.

26. The method of claim 15 wherein the first and second constituents substantially satisfy the compositional formula YPO 4 and the remainder of the phase substantially satisfies the compositional formula ZrSiO 4 .

27. The method of claim 15 wherein the apparatus is formed by a process which comprises firing a green body and said firing is performed on platinum or zirconia.

28. Apparatus for producing a glass or a glass-ceramic, said apparatus comprising a refractory body having a surface adapted to contact the glass or the glass-ceramic when the glass or the glass-ceramic is in a molten state, the refractory body being characterized by at least one of the following:
(1) the refractory body comprises a phase which, on an oxide basis, consists of:
(i) 2.5-13.0 mole percent P 2 O 5 ;
(ii) 2.5-13.0 mole percent Y 2 O 3 , Sc 2 O 3 , Er 2 O 3 , Lu 2 O 3 , Yb 2 O 3 , Tm 2 O 3 , Ho 2 O 3 , Dy 2 O 3 , Tb 2 O 3 , Gd 2 O 3 , or a combination thereof; and
(iii) the remainder of the phase being ZrSiO 4 , HfSiO 4 , ThSiO 4 , or a combination thereof;
wherein:
(a) (i) and (ii) are in a dissolved state in (iii),
(b) the refractory body has a volume of at least 200 cubic centimeters, and
(c) the phase comprises at least 90 volume percent of the refractory body;

(2) the refractory body comprises a phase which, on an oxide basis, comprises:
(i) at least 30 mole percent P 2 O 5 ; and
(ii) at least 30 mole percent Y 2 O 3 , Sc 2 O 3 , Er 2 O 3 , Lu 2 O 3 , Yb 2 O 3 , Tm 2 O 3 , Ho 2 O 3 , Dy 2 O 3 , Tb 2 O 3 , Gd 2 O 3 , or a combination thereof;
wherein:
(a) the refractory body has a volume of at least 200 cubic centimeters, and
(b) the phase comprises at least 90 volume percent of the refractory body; and/or

(3) the refractory body comprises a Phase I and a Phase II wherein:
(a) Phase I, on an oxide basis, consists of:
(i) 2.5-13.0 mole percent P 2 O 5 ;
(ii) 2.5-13.0 mole percent Y 2 O 3 , Sc 2 O 3 , Er 2 O 3 , Lu 2 O 3 , Yb 2 O 3 , Tm 2 O 3 , Ho 2 O 3 , Dy 2 O 3 , Tb 2 O 3 , Gd 2 O 3 , or a combination thereof; and
(iii) the remainder of the phase being ZrSiO 4 , HfSiO 4 , ThSiO 4 , or a combination thereof;
wherein (i) and (ii) are in a dissolved state in (iii);

(b) Phase II, on an oxide basis

Assignees

• Corning Inc

Inventors

• Godard Hilary T
• Tanner Cameron W
• Wallen Michelle M
• Wheeler Elizabeth M

Classifications

• C04B35/447 Primary

  based on phosphates {, e.g. hydroxyapatite} · CPC title

• C04B2235/80

  Phases present in the sintered or melt-cast ceramic products other than the main phase · CPC title

• C04B35/481

  containing silicon, e.g. zircon · CPC title

• C04B2235/3225

  Yttrium oxide or oxide-forming salts thereof · CPC title

• C04B2235/656

  characterised by specific heating conditions during heat treatment · CPC title