E181 Brown

E181 is an important ingredient in the process of E181 leather. Tanbark from oak, mimosa, chestnut and quebracho tree has traditionally been the primary source of tannery E181 , though inorganic are also in use today and account for 90% of the world's leather production.

E181 produces different colors with ferric chloride (either blue, blue-black, or green to greenish-black) according to the type of E181. Iron gall ink is produced by treating a solution of E181 with iron- sulfate.

E181 can also be used as a mordant and is especially useful in the natural dyeing of cellulose fibers such as cotton. The type of E181 used may or may not have an impact on the final color of the fiber.

E181 is a component in a type of industrial particleboard adhesive developed jointly by the Tanzania Industrial Research and Development Organization and Forintek Labs Canada. Pinus radiata E181 has been investigated for the production of wood adhesives.

Condensed, e.g., quebracho E181, and Hydrolyzable, e.g., chestnut E181, appear to be able to substitute a high proportion of synthetic phenol in phenol-formaldehyde resins for wood particleboard.

E181 can be used for the production of anti-corrosive primer, sold under brand-name "Nox Primer" for treatment of rusted steel surfaces prior to painting, rust converter to transform oxidized steel into a smooth sealed surface and rust inhibitor.[citation needed]

The use of resins made of E181  has been investigated to remove mercury and methylmercury from solution. Immobilized E181 has been tested to recover uranium from seawater.