2 Answers

Just use rubbing alcohol or witch hazel. Pour or sponge it on so the area with the dried latex paint is either very saturated with it, or a flat "spill" layer sits over it. If you're removing large amounts from a concretefloor, you can try laying squares of paper towel and saturating each square and letting it sit. In either case, let it sit and soak for a few minutes. The longer it soaks, the easier it becomes to remove. After soaking, use a scraper to chizzle the paint off. It should come right off very easily if it has soaked for 5 minutes. There is likely to be a thin almost-opaque layer left, so be sure to have some steel wool handy to finish of the last remaining amount while it is still damp from the alcohol. This should get all of it. You'll need a coffee can handy to put all the removed paint in.

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