noun
ultrapure water; UPW
Technical term in chemistry and semiconductor manufacturing for water purified to extremely high standards, with very low levels of organic compounds, particles, and dissolved gases.
半導体工場では超純水が大量に使われている。
Ultrapure water is used in large quantities in semiconductor factories.
純水 is general purified water, while 超純水 is a higher grade with stricter impurity limits, used in specialized industrial processes.
Compound of 超 (ultra-) and 純水 (pure water). A modern technical term.