Potassium permanganate, also known as gray manganese oxygen and PP powder, is a common strong oxidant. It is purple-black sheet crystals at room temperature. People often use it as surgical instruments and fruit disinfectants. When the clothes are stained with potassium permanganate, dip the vitamin C tablets in water and apply them to the stain and wipe them gently. While dipping them in water, you can remove the stain in a while. If you are stained with potassium permanganate on your hands, you should also use this method to remove it. It can also be soaked in citric acid or 2% aqueous oxalic acid solution, and the stain can be removed through chemical reactions. This method is suitable for stain removal of clothes of various materials and colors.