Laminated glazing unit

• US 5,208,095 A
• Filed: 08/28/1991
• Issued: 05/04/1993
• Est. Priority Date: 12/17/1990
• Status: Expired due to Term

• Current Assignee: Automotive Components Holdings LLC (Ford Motor Company)
• Original Assignee: Ford Motor Company
• Inventors: Nietering, Kenneth E.
• Primary Examiner(s): Robinson, Ellis P.
• Assistant Examiner(s): Speer, Timothy M.
• Application Number:
  US07/751,379
• Time in Patent Office: 615 Days
• Field of Search: 428/334, 428/336, 428/426, 428/432, 428/433, 428/434, 428/436, 428/437, 428/701, 428/699, 428/215, 428/216, 350/1.6, 350/1.7, 350/164, 350/166, 296/84.1, 296/96.19, 219/203
• US Class Current: 428/215
• 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 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/3613 Coatings of type glass/inorganic compound/metal/inorganic compound/metal/other
• CPC Class Codes: C03C 17/3615 Coatings of the type glass/metal/other inorganic layers, at least one layer being non-metallic
• 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: H05B 2203/013 Heaters using resistive films or coatings
• CPC Class Codes: H05B 3/86 the heating conductors being embedded in the transparent or reflecting material H05B3/845 takes precedence
• CPC Class Codes: Y10T 428/24967 Absolute thicknesses specified
• CPC Class Codes: Y10T 428/24975 No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/263 Coating layer not in excess of 5 mils thick or equivalent
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/31627 Next to aldehyde or ketone condensation product
• CPC Class Codes: Y10T 428/3163 Next to acetal of polymerized unsaturated alcohol [e.g., formal butyral, etc.]

Abstract

A glazing unit comprises a substrate ply and a laminating ply laminated to a surface of the substrate ply. A coating on a laminated surface of the substrate ply is a film stack comprising a film of electrically conductive material covered by a film of dielectric material. The film of dielectric material immediately adjacent the laminating ply comprises a layer of silicon dioxide immediately adjacent the laminating ply and a layer of dielectric material of refractive index greater than 1.5 between the silicon dioxide and the conductive material. Applications include, for example, glazing units for solar load reduction and electrically heated glazing units.

Claims

1. An electrically heatable windshield for a motor vehicle comprising a glass substrate ply, a polyvinyl butyral laminating ply laminated to a surface of the substrate ply, a substantially transparent, electrically conductive coating on the laminated surface of the substrate ply, and means for passing an electrical current through the coating for heating the windshield, the coating consisting essentially of, in order:

a first film of dielectric material immediately adjacent the laminating ply;

a first film of silver metal; and

a film of zinc oxide immediately adjacent the substrate ply;

wherein the first film of dielectric material consists essentially of;

a layer of silicon dioxide about 2 to 10 nanometers thick immediately adjacent the laminating ply; and

a layer of zinc oxide immediately adjacent the silicon dioxide on one side and the film of silver metal on the other, being substantially as thick as the film of zinc oxide.

2. A motor vehicle window comprising a glass substrate ply having a surface laminated to a polyvinyl butyral laminating ply and a substantially transparent, electrically conductive solar load reduction coating on the surface of the substrate ply, sandwiched between the substrate ply and the laminating ply, the solar load reduction coating consisting essentially of, in order, a first film of dielectric material immediately adjacent the laminating ply, a first film of silver metal, a film of zinc oxide, a second film of silver metal, and another film of zinc oxide immediately adjacent the substrate ply, wherein the first film of dielectric material consists essentially of:

a layer of silicon dioxide about 2 to 10 nanometers thick immediately adjacent the polyvinyl butyral laminating ply; and

a layer of zinc oxide immediately adjacent the silicon dioxide on one side and the first film of silver metal on the other, being substantially as thick as the film of zinc oxide immediately adjacent the substrate ply.

3. The motor vehicle windshield of claim 2 wherein the first and second films of silver metal each is about 7 to 9 nm thick, the layer of zinc oxide in the first film of dielectric material and the film of zinc oxide immediately adjacent the substrate ply each is about 28 to 42 nm thick, and the film of zinc oxide sandwiched between the first and second films of silver metal is about 60 to 100 nm to thick.

4. The motor vehicle windshield of claim 2 further comprising means for passing an electrical current through the solar load reduction coating to heat the window.

5. The motor vehicle windshield of claim 2 wherein said solar load reduction coating is a Fabry-Perot interference filter having substantially lower transmittance of IR wavelength radiation than of visible light.