Methods of obtaining photoactive coatings and/or anatase crystalline phase of titanium oxides and articles made thereby

• US 6,677,063 B2
• Filed: 08/30/2001
• Issued: 01/13/2004
• Est. Priority Date: 08/31/2000
• Status: Expired due to Term

• Current Assignee: Vitro Flat Glass LLC (Compagnie De Saint-Gobain)
• Original Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Inventors: Finley, James J.
• Primary Examiner(s): Jones, Deborah
• Assistant Examiner(s): SPERTY, ARDEN B
• Application Number:
  US09/943,163
• Publication Number:
  US 20020045073A1
• Time in Patent Office: 866 Days
• Field of Search: 521/72, 527/861.3, 428/411.1, 428/446, 428/688, 428/689, 428/432, 428/701, 428/702, 428/699, 428/332, 204/192.15, 204/192.22, 204/192.26, 427/585, 427/164-166, 427/350, 427/383.1, 427/383.3, 427/419.1, 427/419.2, 427/376.2
• US Class Current: 428/701
• CPC Class Codes: C03C 17/3417 all coatings being oxide coatings
• CPC Class Codes: C03C 2217/71 Photocatalytic coatings
• CPC Class Codes: C23C 14/024 Deposition of sublayers, e.g. to promote adhesion of the coating C23C14/027 takes precedence
• CPC Class Codes: C23C 14/083 of refractory metals or yttrium
• CPC Class Codes: C23C 14/185 by cathodic sputtering
• CPC Class Codes: C23C 14/5806 Thermal treatment
• CPC Class Codes: C23C 14/5853 Oxidation
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

Hydrophilic and/or rutile and anatase titanium oxide are obtained by sputter depositing titanium metal oxide on a film of zirconium oxide in the cubic phase. Another technique is to deposit a titanium metal on a film of zinc oxide in the cubic phase and heating the coating in an oxidizing atmosphere to provide an anatase and/or rutile phase(s) of titanium oxide.

Claims

1. A method of forming a material having a predetermined crystalline phase, comprising the steps of:

forming a film having cubic or orthorhombic crystalline phase of zirconium oxide over at least a portion of a substrate surface that will enhance the growth of the predetermined crystal phase defined as a first forming step;

forming the material selected from at least one metal oxide or semiconductor metal oxide on the film defined as a second forming step; and

heating at least one of the substrate, the film or the material to have the material have at least one predetermined crystalline phase.

2. The method of claim 1, wherein the first forming step includes forming a zirconium oxide film in the cubic phase.

3. The method of claim 2, wherein the second forming step includes forming a film of material having titanium oxide over the zirconium oxide film, the titanium oxide film having at least one phase selected from anatase or rutile after heating.

4. The method of claim 3, wherein the first and second forming steps are accomplished by sputter deposition.

5. The method of claim 4, wherein the substrate is glass.

6. An article made by the method of claim 3.

7. A transparency made by the method of claim 5.

8. The transparency of claim 7, wherein the transparency is a window.

9. A method of making a photoactive coating, comprising the steps of:

forming a first coating layer comprising zirconium oxide in cubic or orthorhombic crystalline phase over at least a portion of a substrate defined as a first forming step; and

forming a second coating layer comprising titanium oxide over at least a portion of the first coating layer defined as a second forming step to provide a coated substrate.

10. The method of claim 9, including heating at least one of the substrate, the first coating layer, or the second coating layer to make the photoactive coating.

11. The method of claim 9, including heating the substrate prior to or during the first forming step such that the substrate has a temperature greater than or equal to 150°

F. (65°

C.) at the beginning of the first forming step.

12. The method of claim 9, including heating the substrate such that the substrate has a temperature in the range of 100°

F. (38°

C.) to 1000°

F. (537°

C.) during the first forming step.

13. The method of claim 12, including heating the substrate to a temperature in the range of 300°

F. (148°

C.) to 500°

F. (259°

C.).

14. The method of claim 9, including heating the substrate to a temperature in one or more of the following temperature ranges prior to forming the first coating layer:

70°

F. to 500°

F. (21°

C. to 259°

C.);

greater than or equal to 200°

F. (93°

C.);

200°

F. to 1000°

F. (93°

C. to 537°

C.);

or 300°

F. to 500°

F. (148°

C. to 259°

C.).

15. The method of claim 9, wherein the first coating layer has a thickness greater than or equal to 15 Å

.

16. The method of claim 9, wherein the first coating layer has a thickness less than or equal to 150 Å

.

17. The method of claim 9, wherein the first coating layer has a thickness greater than 100 Å

.

18. The method of claim 9, wherein the first coating layer has a thickness less than 500 Å

.

19. The method of claim 9, wherein the first coating layer has a thickness in one or more of the following thickness ranges:

greater than or equal to 15 Å

;

greater than or equal to 25 Å

;

greater than 0 Å and

less than or equal to 150 Å

;

40 Å

to 80 Å

;

60 Å

to 70 Å

;

greater than or equal to 100 Å

;

greater than 0 Å and

less than 500 Å

;

or greater than or equal to 400 Å

.

20. The method of claim 9, including heating the coated substrate to a temperature greater than or equal to about 400°

F. (204°

C.).

21. The method of claim 9, including heating the coated substrate to a temperature greater than or equal to 500°

F. (259°

C.).

22. The method of claim 9, including heating the coated substrate to a temperature greater than or equal to 600°

F. (315°

C.).

23. The method of claim 9, wherein the second coating layer has a thickness greater than or equal to 100 Å

.

24. The method of claim 9, wherein the second coating layer has a thickness greater than or equal to 200 Å

.

25. The method of claim 9, wherein the second coating layer has a thickness in the range of 100 Å

to 500 Å

.

26. The method of claim 9, wherein the second coating layer has a thickness in one of the following thickness ranges:

greater than or equal to 100 Å

;

greater than or equal to 200 Å

;

100 Å

to 500 Å

;

300 Å

to 400 Å

.

27. The method of claim 9, wherein the substrate is glass.

28. The method of claim 9, wherein the photoactive coating is photohydrophilic.

29. The method of claim 9, wherein the photoactive coating is photocatalytic.

30. The method of claim 9, wherein the coated substrate has a contact angle with water of less than or equal to 20°

after 60 to 90 minutes exposure to electromagnetic radiation having a wavelength of 340 nm at an intensity of 24 W/m² at the coating surface.

31. The method of claim 21, wherein the contact angle is less than 10°

.

32. A coated substrate made by the method of claim 9.

33. An article, comprising:

a substrate;

a zirconium oxide layer having cubic or orthorhombic crystalline phases and having a thickness of 10 Å

to 200 Å

formed over at least a portion of the substrate; and

a titanium oxide layer formed over the zirconium oxide layer.

34. The article of claim 33, wherein the zirconium oxide layer has a thickness of 25 Å

to 150 Å

.

35. The article of claim 33, wherein the titanium oxide layer is on the zirconium oxide layer.

36. The article of claim 33, wherein the oxide layer comprises titanium dioxide and has a thickness of 100 Å

to 400 Å

.

37. The article of claim 36, wherein the layer comprising the titanium dioxide has a thickness of 150 Å

to 300 Å

.

38. The article of claim 33, wherein the titanium oxide layer has at least one phase of anatase, rutile, or amorphous phase.

39. An article, comprising:

a substrate;

a first layer deposited over at least a portion of the substrate and comprising zirconium oxide in a cubic or orthorhombic crystalline phase; and

a second layer deposited over the first layer and comprising at least one photoactive material.

40. The article of claim 39, wherein the first layer has a thickness of 10 Å

to 200 Å

.

41. The article of claim 39, wherein the photoactive material includes titanium dioxide.

42. The article of claim 41, wherein the second layer has a thickness of 100 Å

to 400 Å

.

43. The article of claim 41, wherein the titanium dioxide has at least one phase of anatase, rutile, or amorphous phase(s).

44. A method of coating a substrate having a first surface and a second surface, comprising the steps of:

depositing a zirconium oxide layer having a cubic or orthorhombic crystalline phase over at least a portion of the first surface;

forming a photoactive coating comprising a titanium oxide layer on the zirconium oxide layer over at least a portion of the first surface defined as a first forming step; and

forming a functional coating over at least a portion of the second surface defined as a second forming step.

45. The method of claim 44, wherein the first and second forming steps are conducted in the same coater.