Understanding Extractive Bleeding
Extractives include tannins and other polyphenolics, coloring oils, resins, and gums. They contribute to such properties as color, odor, decay and flammability. Water-soluble extractives will cause stain discoloration. Nonwater-soluble extractives such as pitch and resin may bleed through the surface and harden there when the solvent evaporates.
Wood can be finished with Penofin to achieve just about any look desired. Naturally occurring chemicals in the wood itself can migrate to the surface and discolor the finish. The chance of getting discoloration depends on many factors, including wood species, moisture content, and construction practices.
Penofin Pro-Tech Brightener easily removes discoloration caused by extractive bleeding. The active ingredient in Pro-Tech Brightener is oxalic acid, and it's safe and biodegradable formula removes tannins that have risen to the surface. Pro-Tech Brightener removes these tannins and restores wood to its original appearance.
Certain metals commonly found in nails and even sandpaper cause extractive bleeding by mixing with wood tannins causing a dark stain. Pro-Tech Brightener will remove these types of stains quickly and easily by following the directions on the label!