AZ-400-LSW White Thermal Control Paint / Coating

AZ-400-LSW is an extremely low off-gassing organic white thermal control paint developed for use on spacecraft and satellites to coat hard anodized aluminum. A specialized pigment in a silicone binder, AZ-400-LSW can be spray deposited with an air brush or high-volume low-pressure system with the ease of other silicone paints to form a flexible organic nonspecular white marker paint. AZ-400-LSW meets flammability and toxicity requirements of NHB 8060.1C.

The main advantage of AZ-400-LSW relative to AZ-93 and AZW/LA-II is that it has similar very low outgassing but does not require controlled temperature and humidity when applying.

The table below lists the optical and application parameters of cured AZ-400-LSW.


Nominal Surface Resistivity N/A
Thermal Emittance (ε_t) 0.89 ± 0.02
Solar Absorptance (α_s) 0.169 ± 0.02 at ≥ 3.0 mils thickness
Use Temperature Range -180 C to 700 C
Appearance/Color Nonspecular optical white
Nominal Dry Thickness 3.0 ± 1.0mils (over 85% of coated area)
ASTM D3359A Adhesion Grade Not less than 3A
Full Cure 48 to 72 hours

View a typical spectral reflectance curve for AZ-400-LSW (pdf 27KB). Measurements were taken with AZ Technology’s Laboratory Portable SpectroReflectometer LPSR-300.

Note: terms reflectance, emittance and absorptance and terms reflectivity, emissivity and absorptivity are often used interchangeably.