An antimicrobial coating composition consisting essentially of 70 to 80 wt. percent water; 5 to 10 wt. percent methyl alcohol; 3 to 8 wt. percent octadecyl dimethyl trimethoxy silylpropyl-ammonium chloride; 1 to 5 wt. percent chloropropyl trimethoxysilane; 0.5 to 1.5 wt. percent aminopropyltrialkoxysilane; 0.5 to 1.5 wt. percent of a surfactant; 1 to 1.5 wt. percent of an anti-microbial agent; and 0.5 to 2.5 wt. percent sulfuric acid.