اورانوس گودرزی

Three vat dyes، namely C. I. Vat Blue 6، C. I. Vat Yellow 2 and C. I. Vat Red 13، were employed on cotton fabrics in order to provide camouflage in NIR region and imitate reflectance profile of greenish leaves. Results showed that the reflectance curve of dyed fabric with the mixture of dyes when concentration of Vat Blue 6 is 0. 85% (owf) and 1. 2% (owf)، has more similarity with reflectance profile of greenish leaf، which states that vat blue 6 plays an important role in NIR camouflage. Green shades related to deciduous tree leaf and coniferous needle، NATO and forest green were received on cotton fabrics with color difference less than 2، in CIE1976 color space. The results of statistical analyses confirmed the matching of reflectance curves of the samples and the standard (0

Keywords: Camouflage, NIR, Cotton fabric, NATO green, Forest green, Vat dye.

Camouflage، in visual and near infrared region (NIR)، is one of the important topics developed for military purposes. In order to impart camouflage in NIR region، the reflectance profile of the object and its surrounding should be matched. So، the reflectance profile of a selected dye in NIR region is of great importance. If the fabrics are dyed with various pigments and then examined for their power of imparting camouflage in NIR region there would be much waste of human effort and cost to use a reflectance spectrophotometer. To challenge these problems، a new method is developed and reported in this study. For this purpose، a UV-Vis absorbance spectrophotometer is employed and the transmittance profiles of the selected dyes are compared with a known NIR camouflage imparting dye. The novel dye has been studied and evaluated for its potentials as camouflage substance. Since C. I. Vat Blue 13 is one of the camouflage dyes and because structural properties of the dye such as the transmittance curve or the reflectance curve are influenced by its structure، it was concluded that C. I. Vat Blue 6 dye can be used as a camouflage dye in NIR region by similarity of its transmittance curve with that of C. I. Vat Blue 13.