Metal cleaners are used to remove dirt, oil, grease, stains, corrosion oxides, rust particulates, scale and stencil marks. Phosphates and phosphoric acids are used in preparation of acid and alkaline cleaners. Alkaline cleaners are effective for removing solid soils, fatty soils, oils and grease among others. Alkaline cleaners consist of surfactants, water and builders. Acid cleaners are used for removing lime, scale, smut and milkstone among others. Acid cleaners are combination of acids and salts along with detergents and wetting agent.