Most acid stains are a mixture of water, hydrochloric acid, and acid-soluble metallic salts. The acid penetrates the surface and reacts chemically with the hydrated lime in the concrete. Once the stain reacts, it becomes part of the concrete. Like stains for wood, acid stains will vary depending on the color and condition of the substrate they are applied to. Acid stains can be applied in many different ways to obtain endless amounts of unique colors and appearances. |