Low-maintenance coatings

• US 7,713,632 B2
• Filed: 07/12/2005
• Issued: 05/11/2010
• Est. Priority Date: 07/12/2004
• Status: Expired

• Current Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Original Assignee: Cardinal CG Company (Cardinal Glass Industries Incorporated)
• Inventors: Krisko, Annette J., Pfaff, Gary L., Brownlee, James, Myli, Kari
• Primary Examiner(s): Speer; Timothy M
• Application Number:
  US11/179,178
• Publication Number:
  US 20060057298A1
• Time in Patent Office: 1,764 Days
• Field of Search: 428/428, 428/432, 428/446, 428/448, 428/698, 428/699, 428/701, 428/702
• US Class Current: 428/432
• CPC Class Codes: C03C 17/3417 all coatings being oxide coatings
• CPC Class Codes: C03C 17/3423 at least one of the coatings comprising a suboxide
• CPC Class Codes: C03C 2217/212 TiO2
• CPC Class Codes: C03C 2217/213 SiO2
• CPC Class Codes: C03C 2217/71 Photocatalytic coatings
• CPC Class Codes: C03C 2218/155 by reactive sputtering
• CPC Class Codes: C03C 2218/156 by magnetron sputtering
• CPC Class Codes: C23C 14/083 of refractory metals or yttrium
• CPC Class Codes: C23C 14/10 Glass or silica
• CPC Class Codes: C23C 14/568 Transferring the substrates through a series of coating stations C23C14/562 takes precedence

Abstract

The invention provides a substrate bearing a low-maintenance coating. The coating includes two films: a first film comprising silica (e.g., silicon dioxide) and a second film comprising titania (e.g., titanium dioxide). Preferably, both films are provided within particular thickness ranges. The invention also provides methods of depositing such coatings.

Claims

1. A low-maintenance coating on a glass sheet, the coating comprising a first film positioned directly over a first major surface of the glass sheet and a second film positioned directly over the first film, wherein the first film includes a base film and has a thickness of less than about 100 angstroms, and wherein the second film includes a photocatalytic film and has a thickness of less than about 100 angstroms.

2. The low-maintenance coating of claim 1 wherein the base film is silica.

3. The low-maintenance coating of claim 2 wherein the coated first major surface is in periodic contact with rain.

4. The low-maintenance coating of claim 1 wherein the photocatalytic film is titania.

5. The low-maintenance coating of claim 1 wherein the thickness of the first film is between about 70 angstroms and about 100 angstroms.

6. The low-maintenance coating of claim 1 wherein the thickness of the second film is between about 30 angstroms and about 120 angstroms.

7. The low-maintenance coating of claim 1 wherein the glass sheet is a window pane mounted in a window frame, and wherein the coated first major surface is exposed to an outdoor environment.

8. The low-maintenance coating of claim 1 wherein the first film consists essentially of silica and the second film consists essentially of titania.

9. The low-maintenance coating of claim 8 wherein the silica is silicon dioxide, and the titania is titanium dioxide or substoichiometric titanium oxide.

10. The low-maintenance coating of claim 1 wherein the first and second films are both sputtered films.

11. A low-maintenance coating on a glass sheet, the coating comprising a first film positioned directly over a first major surface of the glass sheet and a second film positioned directly over the first film, wherein the first film consists essentially of silica and has a thickness of between about 30 angstroms and about 100 angstroms, and wherein the second film consists essentially of titania and has a thickness of less than 100 angstroms but greater than about 30 angstroms.

12. The low-maintenance coating of claim 11 wherein the second film has a thickness of less than about 80 angstroms.