The mildewcides in paint are molecules that are highly soluble in water. They migrate through the paint film toward the source of moisture and kill any mildew spores that land on the paint's surface before they have a chance to grow.
It's not correct to say that the mildewcides are a liquid or a solid or a gas. They are a solid when dissolved in the latex paint, and thereafter consist of molecules distributed within the paint film.
Because the mildewcide is highly soluble in water, you can remove it from the paint by cleaning the walls unnecessarily often. That will render the paint non-mildew resistant so that mildew may start to grow on it.
Bathrooms are the primary places you want to use a mildew resistant paint in your house. They also put mildewcides in "Kitchen & Bath" paints as well, but just not as much as paints specifically made for bathrooms.
Last edited by Nestor_Kelebay; 10-07-2008 at 10:11 PM.