Transparent substrate with an antireflection, low-emissivity or solar-protection coating

• US 7,005,188 B2
• Filed: 01/18/2001
• Issued: 02/28/2006
• Est. Priority Date: 05/20/1999
• Status: Expired due to Fees

• Current Assignee: Saint-Gobain Glass
• Original Assignee: Saint-Gobain PLC (Compagnie De Saint-Gobain)
• Inventors: Nadaud, Nicolas, Anderson, Charles
• Primary Examiner(s): Morris, Terrel
• Assistant Examiner(s): Piziali, Andrew T.
• Application Number:
  US09/761,765
• Publication Number:
  US 20010031365A1
• Time in Patent Office: 1,867 Days
• Field of Search: 428/412, 428/426, 428/428, 428/432, 428/446, 428/448, 428/689, 428/698, 428/699, 428/702, 442/426, 442/428, 442/432, 442/446, 442/448, 442/689, 442/699, 442/701, 442/702
• US Class Current: 428/432
• CPC Class Codes: B32B 17/10036 comprising two outer glass sheets
• CPC Class Codes: B32B 17/10174 Coatings of a metallic or dielectric material on a constituent layer of glass or polymer
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• CPC Class Codes: C03C 17/3417 all coatings being oxide coatings
• CPC Class Codes: C03C 17/3435 comprising a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/366 Low-emissivity or solar control coatings
• CPC Class Codes: C03C 2217/734 comprising an alternation of high and low refractive indexes
• CPC Class Codes: C03C 27/10 with the aid of adhesive specially adapted for that purpose
• CPC Class Codes: G02B 1/115 Multilayers
• CPC Class Codes: G02B 1/116 including electrically conducting layers
• CPC Class Codes: G02B 1/16 having an anti-static effect, e.g. electrically conducting coatings
• CPC Class Codes: G02B 1/18 Coatings for keeping optical surfaces clean, e.g. hydrophobic or photo-catalytic films G02B1/16 takes precedence

Abstract

A transparent substrate and methods of making a transparent substrate having, on at least one of its faces, an antireflection coating made of a multilayer stack of alternating thin layers of high and low refractive indices. Preferably, the thin layers are based on a dielectric material. At least one of the thin high-index layers comprises titanium oxide which is modified so as to reduce its refractive index to a value of at most 2.40, preferably to a value of at most 2.35.

Claims

1. A transparent substrate having at least one surface comprising, an antireflection coating comprising a multilayer stack having alternating layers of high and low refractive indices, comprising:

(a) at least one high-index multilayer having a refractive index value higher than 1.9 and lower than 2.45, comprising a trilayer with alternatively one titanium oxide layer, one tin oxide layer and one titanium oxide layer; and

(b) at least one low-index layer having a refractive index of from 1.30 to 1.65,

wherein the high-index multilaver is positioned further from the transparent substrate relative to a layer having a refractive index lower than the titanium oxide layer.

2. The transparent substrate of claim 1, wherein said high-index multilayer has a refractive index ranging from 2.25 to 2.38.

3. The transparent substrate of claim 1, wherein said multilayer stack comprises a dielectric material, a low emissivity material, or a solar-protection coating.

4. The transparent substrate of claim 1, wherein said at least one low-index layers comprises one or more of silicon oxide, aluminum oxide, aluminum oxyfluoride, aluminum fluoride, magnesium fluoride, or mixtures thereof.

5. The transparent substrate of claim 4, wherein said at least one low-index layers comprise at least one of halogenated silicon oxide or halogenated aluminum oxide.

6. The transparent substrate of claim 4, wherein the layer of said antireflection coating most removed from said substrate is a low-index layer comprising a SiO2-Al₂O3, wherein the atomic percent of aluminum with respect to silicon is from 5 to 20 percent.

7. The transparent substrate of claim 1, which further comprises a high index layer distinct from the high-index multilayer, having a refractive index of between 1.9 and 2.2 and which comprises tantalum oxide, zirconium oxide, tin oxide, indium oxide, zinc oxide, niobium oxide, silicon nitride, or aluminum nitride.

8. A glazing comprising the transparent substrate of claim 1.

9. The glazing of claim 8, further comprising a layer or multilayer stack that is a solar protection layer, a heat absorbing layer, a UV protecting layer, an antistatic layer, a low emissivity layer, a heated layer, an anti-fouling layer, a hydrophobic organic layer having an anti-rain function, a hydrophilic organic layer having an anti-fogging function, or a silvering layer.

10. The glazing of claim 8, wherein the glazing comprises extra-clear glass or solid-tinted glass.

11. The glazing of claim 8, wherein the glazing comprises a transparent polymer material.

12. The glazing of claim 11, wherein the transparent polymer material comprises a polycarbonate or a polyacrylate.

13. The glazing of claim 8, comprised in internal or external glazing for buildings, a motor-vehicle window, a mirror, a display screen, a decorative glass, a shop window, a shop-counter, or a refrigerated display-cabinet.

14. A motor vehicle window comprising the glazing of claim 8.

15. A mirror comprising the glazing of claim 8.

16. A display screen comprising the glazing of claim 8.

17. A shop window comprising the glazing of claim 8.

18. A glass comprising the glazing of claim 8.

19. The glazing of claim 10, wherein the glazing is toughened, reinforced, curved, or bent.