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Coating/dye that absorbs infrared light but reflects visible light

Coating/dye that absorbs infrared light but reflects visible light

Coating/dye that absorbs infrared light but reflects visible light

(OP)
Hey guys,

I tried asking google multiple times but I could never find a white or transparent dye or coating that is designed to radiate infrared light yet reflect visible light. I would also prefer to be able to integrate the coating in the anodizing in aluminum for better durability. (not sure exactly what makes a dye compatible with anodizing though)

The closest thing I could find is this:
http://www.epolin.com/product/1125#tabs_2

The only problem is that it looks green and I'm not sure how much it will cost.

Background:
Of course, normally, emmissivity is directly proportional to the absortivity - so a blackbody - a fully "black" object in the infrared spectrum would emit as much infrared radiation as possible at a given temperature. Therefore, hot objects that have a coating that absorbs infrared light will cool down faster - that's why black anodized LED flashlights stay about 10 degrees cooler than bare aluminum ones when on a table - it's not just about convection cooling. However, sometimes white objects are more aesthetically pleasing to certain consumers, so it can be useful to have access to a coating that reflects most visible light so it looks "white" or "clear" but absorb (and therefore emit) a high proportion of infrared radiation.

RE: Coating/dye that absorbs infrared light but reflects visible light

"Cold mirrors" will reflect visible light and transmit IR. If the mirror substrate is absorptive it will absorb the transmitted light.

http://en.wikipedia.org/wiki/Cold_mirror

RE: Coating/dye that absorbs infrared light but reflects visible light

(OP)
That isn't exactly a material or something I can just paint over an object though, and dichroic mirrors are pretty expensive if I remember correctly.

RE: Coating/dye that absorbs infrared light but reflects visible light

(OP)
looks interesting, but no mention of infrared absorption anywhere in the pdf

RE: Coating/dye that absorbs infrared light but reflects visible light

I would call a specialist company who focuses on IR absorption, like these folks: http://www.epolin.com/

RE: Coating/dye that absorbs infrared light but reflects visible light

white mesh covering a black substrate. this will still reflect certain IR depending on the mesh size.

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