PALE YELLOW COLOURED AQUEOUS DISPERSION OF SILVER NANOPARTICLES, A PROCESS FOR PREPARATION AND COMPOSITONS THEREOF

摘要

The present invention provides pale yellow coloured aqueous dispersion of silver nanoparticles and process for preparation thereof. The present invention also provides compositions comprising pale yellow coloured aqueous dispersion of silver nanoparticles for use as antimicrobial finish compositions to be applied on textiles and other substrates. The pale yellow coloured aqueous dispersion comprising silver nanoparticles wherein the dispersion is characterized in - having a single plasmonic peak in the range of 390 to 410 nm in UV-Vis spectrum, - the dispersion having silver nanoparticles of spherical shape with majority of particles (>65%) having equivalent diameter in range of 0.2 to 4 nm, - molar extinction coefficient greater than 12 mM-1 cm-1 preferably in the range of 12 to 21 mM-1 cm-1 at wavelength of maximum absorption in the range of 390-410 nm, - Dispersion stability of at least 15 months, - Minimum Bactericidal Concentration (MBC) lower than 0.3 ppm preferably in the range of 0.03-0.25 ppm.