Glazing panel carrying a coating stack

• US 20060139783A1
• Filed: 02/03/2004
• Published: 06/29/2006
• Est. Priority Date: 02/14/2003
• Status: Active Grant

• Current Assignee: AGC Flat Glass (AGC, Inc.)
• Original Assignee: AGC Flat Glass (AGC, Inc.)
• Inventors: Decroupet, Daniel
• Granted Patent: US 7,494,717 B2
• Time in Patent Office: Days
• US Class Current: 359/883
• CPC Class Codes: C03C 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/3618 Coatings of type glass/inorganic compound/other inorganic layers, at least one layer being metallic
• CPC Class Codes: C03C 17/3626 one layer at least containing a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/3634 one layer at least containing carbon, a carbide or oxycarbide
• CPC Class Codes: C03C 17/3639 Multilayers containing at least two functional metal layers
• CPC Class Codes: C03C 17/3644 the metal being silver
• CPC Class Codes: C03C 17/3652 the coating stack containing at least one sacrificial layer to protect the metal from oxidation
• CPC Class Codes: C03C 17/366 Low-emissivity or solar control coatings
• CPC Class Codes: C03C 17/3681 the multilayer coating being used in glazing, e.g. windows or windscreens
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: C23C 14/0015 characterized by the colour of the layer
• CPC Class Codes: C23C 14/185 by cathodic sputtering
• CPC Class Codes: C23C 14/5806 Thermal treatment

Abstract

A glazing panel has a coating stack comprising in sequence at least a base antireflective layer, an infra-red reflecting layer, a top antireflective layer and a top coat layer comprising at least one material selected from the group consisting of nitrides, oxynitrides, carbides, oxycarbides and carbonitrides of the elements of groups lVb, Vb and VIb of the periodic table.

Claims

1. A glazing panel carrying a coating stack comprising in sequence at least:

a glass substrate

a base antireflective layer

an infra-red reflecting layer,

a top antireflective layer

a top coat layer

in which the glazing panel is adapted to be heat treated

and in which the top coat layer comprises at least one material selected from the group consisting of nitrides, oxynitrides, carbides, oxycarbides and carbonitrides of the elements of groups IVb, Vb and VIb of the periodic table.

15. A glazing panel in accordance with claim 1 which is adapted for assembly in a double glazing unit.

16. A glazing panel in accordance with claim 15, in which the glazing panel is adapted for assembly in a double glazing unit with the coating stack in position 3.

17. A glazing panel in accordance with claim 15, in which the glazing panel is adapted to be heat treated prior to assembly in a double glazing unit.

18. A double glazing unit comprising at least one heat-treated glazing panel in accordance with claim 1.

19. A double glazing unit in accordance with claim 18, in which the double glazing unit gives a colour in reflection seen from the outside such that a* is between 0 and −

4 and b* is between 0 and −

7.

20. A double glazing unit in accordance with claim 18, in which the double glazing unit has a luminous transmittance of greater than 70%.

25. A method in accordance with claim 21, in which the intermediate heat treated glazing panel comprises a glazing panel in accordance with claim 1.

27. A method of manufacturing a glazing panel having a haze of less than about 0.5 comprising the step of subjecting a glazing panel in accordance with claim 1 to a tempering and/or bending operation at [[at]] least 570°

C.

28. A glazing panel in accordance with claim 1 , including at least one of the following characteristics (a) through (c):

(a) the coated glazing panel has a luminous transmittance of greater than 70%;

(b) the coated glazing panel provides a substantially neutral colour in reflection;

(c) a heat treatment provokes an increase in the luminous transmittance of the glazing panel.

29. A glazing panel in accordance with claim 1, includes at least one of the following (a) and (b):

(a) at least one of the antireflective layers comprises an oxide; and

(b) at least one of the antireflective layers comprises a mixed oxide of zinc and one or more of tin, aluminium and titanium.

30. A glazing panel in accordance with claim 1, the base antireflective layer comprising at least one layer comprising a mixed oxide of zinc and tin.

31. A glazing panel in accordance with claim 1, the base antireflective layer consisting essentially of mixed oxides of zinc and tin.

32. A glazing panel in accordance with claim 1, wherein the top antireflective layer comprises at least one layer comprising a mixed oxide of zinc and tin.

33. A glazing panel in accordance with claim 1, wherein the top coat includes at least one of the following (a) through (d):

(a) the top coat layer consists essentially of a material selected from the group consisting of nitrides and oxynitrides of the elements of groups IVb , Vb and VIb of the periodic table;

(b) the top coat layer consists essentially of a material selected from the group consisting of titanium nitride, chromium nitride, zirconium nitride, titanium oxynitride, chromium oxynitride, zirconium oxynitride and mixtures thereof;

(c) the top coat layer comprises titanium nitride;

(d) the top coat layer has a geometrical thickness in the range 15 to 50Å

.

34. A glazing panel in accordance with claim 1, further including a barrier layer between the infra-red reflecting layer and the top antireflective layer.

35. A glazing panel in accordance with claim 34, in which the barrier layer includes at least one of the following (a) through (c):

(a) the barrier layer comprises a first barrier layer in substantially metallic form and an overlying second barrier layer of a different composition from the first barrier layer which is in a form selected from the group consisting of oxides, sub-stoichiometric oxides, nitrides, sub-stoichiometric nitrides, oxynitrides and sub-stoichiometric oxynitrides;

(b) the barrier layer comprises a first barrier layer comprising nickel and chromium and an overlying second barrier layer comprising titanium;

(c) a barrier layer selected from the group consisting of a barrier layer comprising nickel and chromium, a barrier layer comprising titanium, and a barrier layer comprising a first barrier layer comprising nickel and chromium and an overlying second barrier layer comprising titanium.

36. A glazing panel in accordance with claim 1, including:

the base antireflective layer comprising at least one layer comprising a mixed oxide of zinc and tin;

a barrier layer between the infra-red reflecting layer and the top antireflective layer;

the top antireflective layer consisting essentially of mixed oxides of zinc and tin; and

the top coat layer comprises at least one material selected from the group consisting of nitrides, oxynitrides, carbides, oxycarbides and carbonitrides of the elements of groups IVb , Vb and VIb of the periodic table.

37. A glazing panel in accordance with claim 1, in which the glazing panel consists essentially of, in sequence,

a glass substrate

a base antireflective layer consisting essentially of mixed oxides of zinc and tin;

an infra-red reflecting layer,

a barrier layer selected from the group consisting of a barrier layer comprising nickel

and chromium, a barrier layer comprising titanium, and a barrier layer comprising a

first barrier layer comprising nickel and chromium and an overlying second barrier

layer comprising titanium;

a top antireflective layer consisting essentially of mixed oxides of zinc and tin; and

a top coat layer consisting essentially of titanium nitride.

2-14. -14. (canceled)

21. A method of manufacturing a heat treated glazing panel comprising the steps of, in order:

a) depositing a coating stack on a glass substrate to provide an intermediate glazing panel comprising, in sequence, at least;

a glass substrate

a base antireflective layer

an infra-red reflecting layer, [[and]]

a top antireflective layer, and

a top coat layer which comprises at least one material selected from the group consisting of nitrides, oxynitrides, carbides, oxycarbides and carbonitrides of the elements of groups IVb, Vb and VIb of the periodic table.

b) subjecting the coated, intermediate glazing panel to a heat treatment process in air at a temperature of greater than 550°

C.

22. A method in accordance with claim 21 comprising the steps of:

a) depositing a coating stack on a glass substrate to provide an intermediate glazing panel with a luminous transmittance of greater than 75%;

b) subjecting the coated, intermediate glazing panel to a heat treatment process in air at a temperature of greater than 550°

C.;

c) providing a heat treated glazing panel with a luminous transmittance of greater than 85%.

23. A method in accordance with claim 21, in which heat treatment of the intermediate glazing panel causes substantial oxidation of the top coat layer.

24. A method in accordance with claim 21, in which the luminous transmittance of the heat treated glazing panel following the step of heat treatment is greater than the luminous transmittance of intermediate glazing panel by at least 8%.

26. Use of a top coat layer which comprises at least one material selected from the group consisting of nitrides, oxynitrides, carbides, oxycarbides and carbonitrides of the elements of groups IVb, Vb and VIb of the periodic table to enhance chemical durability before heat treatment of a heat treatable coated glazing panel having at least one metallic infra red reflecting coating layer sandwiched between dielectric layers.