In order to match the reflectance profile of the greenish leaf at NIR region, four commercially available vat dyes were used to dye cotton fabrics. The reflectance of dyed fabric and the transmittance of dye liquor in alcohol solution were measured by using U-4100 spectrometer with an integrating sphere. The effects of the combination dyeing, dyeing concentration (% owf) and fabric weaves on the reflectance were also studied. The results show that the reflectance of the combination dyeing is determined by one of the dyes whose reflectance curve emerges at longer wavelengths. Vat Blue 13 plays an important role in green camouflaging. When the dyeing concentration of vat blue 13 is 1-2% owf, the reflectance of the dyed fabric almost overlaps that of greenish leaf in red shift region (region A). Fabric weave has a little effect on the reflectance for the same dyeing program.
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