Ultra-pure water was originally produced by distillation, deionization, reverse osmosis technology or other appropriate supercritical fine technology in order to develop ultra-pure materials (semiconductor original materials, nano fine ceramic materials, etc.) in the United States science and technology, and now ultra-pure water has been widely used in biology, medicine, automobiles and other fields. This water in addition to water molecules (H20), almost no impurities, no bacteria, viruses, chlorine-containing dioxins and other organic matter, of course, there is no mineral trace elements required by the human body, ultra-pure water without hardness, taste more sweet, also known as soft water, can be directly drinkable, can also be boiled to drink. Ultra-pure water is a degree that is difficult to achieve by the general process, such as water resistivity greater than 18MΩ*cm, close to 18.3MΩ*cm is called ultra-pure water.