@Dr. Acula , it depends on what their chemical engineer says when building a continuous manufacturing process. From a cost-per-gallon standpoint I'm almost 100% sure they'd use DI water.
That doesn't mean we should use DI or distilled water when concocting coolant from pure stuff-in-a-jug and water unless the antifreeze manufacturer says so. This is addressed at the end of this post.
DI water is water treated to remove ions, usually dissolved mineral salts. DI water can still have organic contaminants.
Water heated, steam collected, condensed ... that's distilled water. That process addresses most impurities.
My guess is that any plant first receives water from a municipal water supply, performs mechanical filtration, then runs it through a DI system with ion exchange resins (both types). Now, they can add whatever is needed: glycol as antifreeze, and everything else needed for corrosion protection, pH range stability, and appropriate metallic salts to address the ionic balance that the Rislone people mention in layman's terms.
If they did that very last part to pure antifreeze, they would tell you to use distilled water on the jug (just like Ford does).
Again, given how few times I ever service any cooling system, I'm just going to buy 50/50 Honda Type 2 and account for the extra cost by not drinking beer that week.
OF