Development and characterisation of near-infrared camouflage fabrics for military combat uniform

Modern camouflage must extend beyond the visible spectrum to address the threats posed by night vision devices, particularly in the near-infrared (NIR) range. This study investigates the use of nano additives, silicon dioxide (SiO₂) and titanium dioxide (TiO₂), embedded in fabric through surface dyeing and pigmentation technologies to improve both visible and NIR camouflage performance. The study’s objectives also include assessing the flammability risks of these additives and comparing the spectral reflectance and colour stability of reactive versus pigment dye-printed fabrics. The NIR fabric exhibited spectral reflectance values ranging from 5 to 20% for blue-black, 25–40% for brown, 15–50% for green, and 45–74% for beige. Field trials showed a noticeable improvement in camouflage performance, with NIR-treated fabrics blending more effectively into natural foliage when viewed through night vision devices. Repeated washing led to increased NIR reflectance in some colours and colour different, particularly for the pigment-dyed fabrics, with a maximum ΔE of 4.3 in brown after 20 washes, surpassing the acceptable military specification of 2.0. The flammability tests on NIR fabrics revealed some concerns regarding the health and safety of such fabrics in military applications. The NIR fabrics showed higher flammability compared to Non-treated Fabric, indicating that further improvements are necessary to reduce flammability risk while maintaining the desired camouflage properties. This research offers a practical approach to advancing NIR camouflage technology for military applications, showing promising improvements in both performance and durability.