Patent ID: 8737827

Claim:
A sauna heating element including a high-emissivity coating, the sauna heating element comprising: a heating component that increases in temperature when voltage is applied across the heating component; a substrate in operable contact with the heating component, such that when the heating component increases in temperature, it warms the substrate to a first temperature; and a film coating in contact with the substrate, the film coating comprising: a liquid layer that is in contact with the substrate and has a dry film thickness of about 1.0 mil to about 5.0 mils, the liquid layer comprising: a polyamide-imide type coating resin, a solvent, and a first black ceramic pigment having an average primary particle size of 0.1 micrometer to 10 micrometers, wherein the ratio of the polyamide-imide type coating resin to the first black ceramic pigment is about 1.0:0.5 to about 1.0:3.0, and a powder layer that is in contact with the liquid layer, the powder layer comprising a second black ceramic pigment having a uniform surface area density of about 5 grams of the second black ceramic pigment per square foot of the film coating to about 15 grams of the second black ceramic pigment per square foot of the film coating.