UMITAN TA / AR CONC. dust is a synthetic tannin weakly acid indicated for use as pre-tanning agent for vegetable leathers. It can 'be used as a weak retanning of chrome leather. UMITAN TA / AR CONC. It is easily miscible with water. It penetrates rapidly and uniformly improving the penetration of the subsequently added plant materials, thus allowing the obtaining of a clean and uniform color of a flower end and smooth.