Ethanol is more effective at a concentration of 50-70 percent; below 20 per cent, its bactericidal action is negligible.
乙醇的浓度为50%至70%时比较有效，浓度低于20%时，杀菌能力基本上就不存在了。
英语百科
Bactericide
（重定向自Bactericidal）
A bactericide or bacteriocide, sometimes abbreviated Bcidal, is a substance that kills bacteria. Bactericides are disinfectants, antiseptics, or antibiotics.