Copper-free mirror having acrylic and polyurethane paint layers free of alkyd

Patent metadata

Field	Value
Publication number	US-9372284-B2
Application number	US-201113994765-A
Country	US
Kind code	B2
Filing date	Dec 15, 2011
Priority date	Dec 17, 2010
Publication date	Jun 21, 2016
Grant date	Jun 21, 2016

Abstract

Mirrors with no copper layer according to the present invention comprise a glass substrate, a silver coating layer provided at a surface of the glass substrate and at least two paint layers covering the silver coating layer, the outermost paint layer comprising a polyurethane resin based paint. They are characterized in that the paint layers are free of alkyd resin and in that the first paint layer closest to the silver coating layer has a thickness of at least 10 μm.

First claim

The invention claimed is:

1. A mirror, comprising:
a glass substrate,
a silver coating layer at a surface of the glass substrate, and
at least two paint layers covering the silver coating layer, wherein
the at least two paint layers are free of alkyd resin,
an outermost paint layer comprises a polyurethane resin based paint,
at least one paint layer between the silver coating layer and the outermost paint layer comprises an acrylic resin based paint,
a paint layer closest to the silver coating layer has a thickness of at least 10 μm, the mirror is free of any copper layer, and
the mirror can withstand 3 cycles of both a 2500 hour Q-panel test as defined in ASTM Standard G53-88 and a 5-day CASS test as defined in International Standard ISO 9227-1990 without complete paint delamination.

2. The mirror of claim 1 , wherein the mirror comprises three paint layers.

3. The mirror of claim 1 , wherein the mirror comprises, in an order of covering the silver coating layer:
a first paint layer comprising an acrylic resin based paint,
a second paint layer comprising an acrylic resin based paint, and
the outermost paint layer comprising a polyurethane resin based paint.

4. The mirror of claim 1 , wherein the mirror comprises, in an order of covering the silver coating layer:
a first paint layer comprising an acrylic resin based paint,
a second paint layer comprising an epoxy resin based paint, and
the outermost paint layer comprising a polyurethane resin based paint.

5. The mirror of claim 1 , wherein the silver coating layer has a thickness of at least 1000 Å.

6. The mirror of claim 1 , wherein
the mirror comprises two paint layers,
a first paint layer has a thickness of from 20 to 45 μm, and
the outermost paint layer has a thickness of from 25 to 50 μm.

7. The mirror of claim 2 , wherein
a first paint layer, closest to the silver coating layer, has a thickness of from 20 to 45 μm,
a second paint layer, between the first paint layer and the outermost paint layer, has a thickness of from 20 to 45 μm, and
the outermost paint layer has a thickness of from 25 to 50 μm.

8. The mirror of claim 1 , wherein the glass substrate is an extra-clear glass with a total iron content expressed as Fe 2 O 3 of less than 0.02% by weight.

9. A mirror, comprising:
a glass substrate,
a silver coating layer at a surface of the glass substrate, and
at least two paint layers covering the silver coating layer,
wherein
the at least two paint layers are free of alkyd resin,
an innermost paint layer is in direct contact with the silver layer,
an outermost paint layer comprises a polyurethane resin based paint,
at least one paint layer between the silver coating layer and the outermost paint layer comprises an acrylic resin based paint,
a paint layer closest to the silver coating layer has a thickness of at least 10 μm,
the mirror is free of any copper layer, and
the mirror can withstand 3 cycles of both a 2500 hour Q-panel test as defined in ASTM Standard G53-88 and a 5-day CASS test as defined in International Standard ISO 9227-1990 without complete paint delamination.

10. The mirror of claim 9 , wherein the mirror comprises three paint layers.

11. The mirror of claim 9 , wherein the mirror comprises, in an order of covering the silver coating layer:
the innermost paint layer comprising an acrylic resin based paint,
a second paint layer comprising an acrylic resin based paint, and
the outermost paint layer comprising a polyurethane resin based paint.

12. The mirror of claim 9 , wherein the mirror comprises, in an order of covering the silver coating layer:
the innermost paint layer comprising an acrylic resin based paint,
a second paint layer comprising an epoxy resin based paint, and
the outermost paint layer comprising a polyurethane resin based paint.

13. The mirror of claim 9 , wherein the silver coating layer has a thickness of at least 1000 Å.

14. The mirror of claim 9 , wherein the mirror has only two paint layers and
the innermost paint layer has a thickness of from 20 to 45 μm, and
the outermost paint layer has a thickness of from 25 to 50 μm.

15. The mirror of claim 10 , wherein
the innermost paint layer has a thickness of from 20 to 45 μm,
a second paint layer, between the first paint layer and the outermost paint layer, has a thickness of from 20 to 45 μm, and
the outermost paint layer has a thickness of from 25 to 50 μm.

16. The mirror of claim 9 , wherein the glass substrate is an extra-clear glass with a total iron content expressed as Fe 2 O 3 of less than 0.02% by weight.

17. The minor of claim 1 , wherein the mirror can withstand a thermal cycling plus humidity test of 4 cycles per day between −20° C. to 75° C. and back to 20° C. under greater than 98% relative humidity for 252 days and exhibit paint peeling of less than 1 mm.

Assignees

• Ventelon Lionel
• Cosijns Bruno
• Agc Glass Europe

Inventors

• Ventelon Lionel
• Cosijns Bruno

Classifications

• C03C17/38

  at least one coating being a coating of an organic material · CPC title

• G02B1/105 Primary

  Physics · mapped topic

• C03C17/3663 Primary

  specially adapted for use as mirrors · CPC title

• G02B5/0808

  having a single reflecting layer (G02B5/0883, G02B5/0891 take precedence) · CPC title

• G02B1/14 Primary

  Protective coatings, e.g. hard coatings · CPC title