污色 meaning in English

contact stain

Testing method for colour fastness to alkali spotting
耐碱斑污色牢度的试验方法
Testing method for colour fastness to water spotting
耐水斑污色牢度的试验方法
Testing method for colour fastness to acid spotting
耐酸斑污色牢度的试验方法
Dual - action toothpaste with xylitol and baking soda to remove stains and surface discolouration from teeth . leaves teeth sparkling white and mouth minty fresh . suitable even for sensitive teeth
这种双重作用的牙膏，含有木糖醇和小苏打，能清除牙齿表层的污垢和污色。用后，牙齿显得更洁白亮丽，而且满口清香。敏感性的牙齿亦适用。