VAR-0.25 is a broad band antireflection coating that is commonly used in demanding sunlight readability applications.
Reflection:
The reflection of the coating shall meet the reflection reducing requirements of MIL-C-14806.
Adhesion:
The coating shall show no evidence of damage when an approved tape is pressed firmly against the coated surface and quickly removed normal from the surface. (Reference MIL-PRF-13830B, Appendix C, para. C.4.5.12)
Abrasion:
The coating shall show no evidence of deterioration after being subjected to a 40-rub eraser test using a rub force of 2-2-1/2 lbs. (Reference MIL-PRF-13830B, Appendix C, para. C.4.5.10)
Humidity:
The coating shall show no evidence of deterioration after being subjected to a continuous exposure of 120°F ± 4°F and 95-100% relative humidity. Following exposure, the coating shall pass the Abrasion (eraser) test with no evidence of deterioration. (Reference MIL-PRF-13830B, Appendix C, para. C.4.5.8)
Salt Solubility:
The coating shall show no evidence of deterioration after being subjected to immersion for a period of 24 hours in a solution of water and 170 grams of salt per 3.8 liters of water. Following exposure, the coating shall pass the Abrasion (eraser) test with no evidence of deterioration. (Reference MIL-PRF-13830B, Appendix C, para. C.4.5.7)
Temperature Shock:
The coating shall show no evidence of deterioration after being exposed to a temperature of 160°F, then -65°F and then 160°F again for 4 hours each. Transfer time between temperatures to be minimal. Following exposure, the coating shall pass the Abrasion (eraser) test with no evidence of deterioration. (Reference MIL-STD-810, Method 503.5, Procedure 1a)
Salt fog:
The coating shall show no evidence of deterioration after exposure to a salt spray fog for a continuous period of 24 hours in accordance with ASTM B117. Following exposure, the coating shall pass the Abrasion (eraser) test with no evidence of deterioration. (Reference MIL-STD-810, Appendix C, para. 4.5.9)
Additional specifications can be integrated into design considerations including fluid exposure to solvents, fuel, cleaning fluids, and other chemicals.
