Solar screening film for a vehicle windshield

• US 5,189,551 A
• Filed: 07/27/1989
• Issued: 02/23/1993
• Est. Priority Date: 07/27/1989
• Status: Expired due to Fees

• Current Assignee: Monsanto Company St Louis Missouri
• Original Assignee: Monsanto Company (Bayer AG)
• Inventors: Woodard, Floyd E.
• Primary Examiner(s): Arnold, Bruce Y.
• Assistant Examiner(s): Shafer, R. D.
• Application Number:
  US07/385,527
• Time in Patent Office: 1,307 Days
• Field of Search: 350/1.7, 350/164, 350/166, 350/276 R, 350/276 SL, 350/319, 296/84.1, 296/96.19, 219/203, 359/350, 359/359, 359/360, 359/580, 359/585, 359/588, 359/589, 359/601, 359/885, 359/894, 428/423.1, 428/430, 428/457, 428/458
• US Class Current: 359/360
• CPC Class Codes: B32B 27/36 comprising polyesters
• CPC Class Codes: B60J 1/002 with means for clear vision, e.g. anti-frost or defog panes, rain shields window heating in H05B3/84, H05B3/86
• CPC Class Codes: G02B 1/10 Optical coatings produced by application to, or surface treatment of, optical elements G02B1/08 takes precedence
• CPC Class Codes: G02B 1/116 including electrically conducting layers
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• CPC Class Codes: G02B 2027/012 comprising devices for attenuating parasitic image effects
• CPC Class Codes: G02B 2027/0194 with combiner of laminated type, for optical or mechanical aspects
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 5/28 Interference filters
• CPC Class Codes: H05B 3/84 Heating arrangements specially adapted for transparent or reflecting areas, e.g. for demisting or de-icing windows, mirrors or vehicle windshields
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/31678 Of metal

Abstract

A solar screening film for a motor vehicle windshield comprises an interference filter having one or more heat reflecting metal layers and one or more coacting reflection-suppressing layers to minimize reflection and enhance visible transmission and a gradient band continuation of the interference filter above the direct line of forward vision through a windshield when the film is disposed therein in a motor vehicle, for reflective rejection of infra-red solar energy, such band including a light-reflecting metal layer gradually increasing in thickness toward an edge of the film.

Claims

1. A solar screening film for a motor vehicle windshield comprising:

(a) an interference filter segment comprising two or more light-reflecting metal layers, each surface of which is contiguous with a dielectric layer; and

(b) an integral gradient band continuation of said interference filter above the direct line of vision through a windshield when said solar screening film is disposed in a motor vehicle, for reflective rejection of infra-red solar energy, said band including an extension of one of the light-reflecting metal layers gradually increasing in thickness toward a marginal edge of the film.

2. The film of claim 1 wherein the two or more light-reflecting metal layers of the interference filter segment are of substantially uniform thickness.

3. The film of claim 2 wherein the gradient band continuation includes extensions of each of the dielectric layers of the interference filter segment.

4. The film of claim 3 wherein the thicknesses of the extensions of the dielectric layers of the gradient band continuation are substantially the same as the thicknesses of the dielectric layers of the interference filter segment.

5. The film of any of claims 1, 2, 3 or 4 wherein the varying thickness of the metal layer of the gradient band continuation increases from about 60 to 200 Angstroms at the confluence with the interference filter segment to about 200 to 1000 Angstroms.

6. The film of claim 5 wherein each metal layer of the interference filter segment and of the gradient band continuation comprises silver.