Bi-Band Low-Observable Coatings

Table 1 : Technical characteristics of LPRL band II/III coating. 

e (band II)

0.56 < e < 0.62

e (band III)

0.72 < e < 0.77

Maximum Temperature

180 C / 356 F

Min. Thickness

50 mm / 2 mil


1.3 gm/cm3

Weight Penalty [1]

0.013 lbs/ft2

At right is shown a thermograph taken with a bolometric infrared camera (a band III infrared camera) of an LPRL bi-band coating compared to a NATO black coating. The sample consisted of an aluminum plate which was heated on a hot plate to 60 degrees Celsius. The aluminum plate was coated with a NATO black coating,, which contains some aluminum powder to lower its emissivity. In the right hand region of the figure is an LPRL coating which was deposited over the black coating.

The apparent temperature is indicated for each region, and shows that the LPRL coating results in a reading 4 degrees Celsius (or 7 degrees Fahrenheit) below that of the black coating. From this image we estimate the emissivity in band III of the LPRL coating to be 0.72.

LPRL provides additives that simultaneously give polyurethane paints infrared low observable characteristics in bands II and III. LPRL also offers prepared polyurethane band II/III coatings that do not compromise radar cross-section reduction schemes, are compatible with a variety of primers, and may be applied using standard technology (e.g., spray gun). For information on how we can help you obtain infrared discretion, please contact us at

LPRL’s lightweight coatings provide stealth characteristics in bands II and III without significantly altering the thermal exchange properties of the substrate or compromising radar stealth.  The emissivity e of LPRL band II/III coatings may be tuned to meet the demands of the application, from a minimum of 0.59 in band II (3 to 5 mm) or 0.75 in band III (8 to 12 mm).
Some key characteristics LPRL’s band II/III coating are shown in the table at left.

LPRL, 18-20 rue des Presles, 75015 Paris, FRANCE