ANTIBACTERIAL TREATMENT OF GLASS VESSEL

PROBLEM TO BE SOLVED: To carry out uniform ion exchange to generate no unevenness in coating and to obtain a glass vessel capable of being easily washed with water even if contamination occurs, free from coloring and excellent in antibacterial activity by coating the inner surface of a glass vessel with an aq. soln. contg. silver nitrate and a surfactant and heat-treating the vessel at a temp. at which the ion exchange of alkali metal ions in the surface layer of the vessel for Ag ions is caused. SOLUTION: Silver nitrate has high solubility to water, gives a high concn. uniform soln. and prevents the reduction coloring of silver by its high oxidizing power. The concn. of the silver nitrate used is 5-25 wt.%. The surfactant sufficiently reduces the surface tension of the aq. soln. for ion exchange and enables uniform coating. The concn. of the surfactant used is 0.1-2 wt.%. An organosilver compd. such as silver lactate may be dissolved in place of silver nitrate. The heat treatment temp. is preferably 320-470 deg.C. The glass vessel may be any glass vessel. provided that it contains alkali metal ions. The coating method is not particularly limited and spraying or dipping may be adopted.