Near-infrared green camouflage of cotton fabrics using vat dyes
Level 5 - mechanism / opinion, no new human data
Level 5 by design analogy (in vitro materials/textile laboratory experiment with no human subjects)
OpenAlex W2074368431 · doi:10.1080/00405000701556392
What was done
Four commercially available vat dyes were applied to cotton fabrics to match the near-infrared (NIR) reflectance profile of green leaves. Spectral reflectance of dyed fabric and transmittance of dye liquor in alcohol were measured using a U-4100 spectrometer with an integrating sphere. The authors evaluated the effects of dye combinations, dye concentration (% owf), and fabric weave on reflectance.
What was found
Combination dyeing reflectance was determined by the dye exhibiting reflectance at longer wavelengths. Vat Blue 13 was identified as the critical component for green camouflage: at 1–2% owf concentration, the dyed fabric reflectance closely overlapped that of a green leaf in the red-shift region (region A). Fabric weave showed little effect on reflectance for the same dyeing program. Specific numerical reflectance percentages were not reported in the abstract.
Why it matters
It demonstrates a method to mimic natural foliage NIR spectral signatures on cotton textiles using standard commercial vat dyes.
Limits
This was an in vitro materials experiment with no testing of real-world outdoor performance, field detection, washfastness, or environmental degradation. Sample sizes and detailed quantitative spectral data are absent from the abstract.
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