Naturally occurring substances, widely used in dry cleaning and for tanning hides. They also have medicinal uses as astringents. Due to its content of tannic acid are used as a mordant in the fixing of the colors in fabrics and fabrics so permanent, something very useful in the textile industry and dyeing. They are very polluting substances from water currents.
* Only one "like" per meaning and day, the more "likes" the meaning will appear higher in the list