Green camouflage coating for fabric screen printing

This work proposes a preparation method for a green camouflage coating suitable for fabric screen printing to simulate green vegetation for military camouflage applications. Four water-based pigment dispersions were selected. This study established Scheffe's second-degree mathematical models and developed 20 possible experiments to investigate the influence of four pigment dispersion ratios on the camouflage performance of coatings. Binders, drying retardants, and thickeners were mixed with pigment dispersions and then scraped onto the fabric's surface through screen printing. The spectral reflectance of the coatings in the range of 380-1100 nm was measured. The response index values of these coatings were then calculated. Generalized regression obtained the relationship model between the index and the four pigment dispersion ratios. Results showed that the green camouflage coating had the best camouflage effect when the mass ratio of the pigment dispersion was 40% cobalt blue, 9.2% chrome green, and 50.8% cadmium yellow. The reflectance ratio of the coating in the near-infrared and red bands was not less than 5, the color difference with vegetation green was less than 3, and the near-infrared brightness contrast with vegetation green did not exceed 0.2. The coating's reflectance was located in the hyperspectral channel of vegetation green, meeting the camouflage requirements. This study provides theoretical guidance for preparing and practically producing other camouflage colors.