Industrial purposes of deionized water can never be refuted.
It claims extensive application in the semiconductor industry as it is used during processing and cleaning of materials like silicon wafers.
The optics industry also relies on this type of highly pure water, since optical surfaces are supposed to be extremely clean as a requirement for coating.
Laboratory glassware’s are rinsed in DI water as tap water is never recommended for this purpose.
Water that is devoid of ions is also used in car wash shops. Many super car companies use this type of water during final preparation for when the motor vehicles are presented to their clients.
It is very suitable and is in fact used in window cleaning.
The efficacy of this pure water as a cleaning agent is due to its aggressiveness as a solvent, since water that contains no dissolved ions will tend to draw ions or solutes from the surroundings and surfaces.
This means no spots or stains is left on surfaces.