The windscreen is a very important part of any vehicle, through which the driver evaluates the road situation to make decisions. In summer, the glass can be kept clean using regular water, but in winter time this obviously will not work. The windscreen wash system can be ruined by the freezing water.
Special non-freezing liquids are used in the cold season. A good quality of the washing liquid can handle glass cleaning even in cold weather, and efficiently remove dirt, film and ice.
So what are the ingredients of window wash liquids? First of all, they include surfactants, with washing effect. To keep the glass clean, a 1-2% surfactant solution is sufficient. Aromatizers and dyes are also needed. The former remove odors, the latter make the product look better. Water is also important: distilled water is the best choice. Regular tap water does not work, because it will cause sediment of mineral salts and chalk, scratching the windshield glass.
The most important part, which prevents the non-freezing fluid from freezing – alcohol. Ethanol and isopropyl are mostly harmless for humans. Methanol is cheaper, but cannot be used to make washing fluid, being highly toxic. Vapor coming in through ventilation system can poison the driver and passengers. Vertigo, dizziness, visual impairment, neurological and vascular system damage are some of the effects.
One of the most important things is that the declared minimal temperature compoes with the actual one. The fluid must not leave traces after use. It must also not be aggressive to the paint of the vehicle, plastic and rubber parts of the automobile etc.