Tannic acid

Main Application Areas

Leather Industry

Most traditional application: Utilizing the precipitation reaction between tannic acid and skin collagen (protein) to denature and cross-link the collagen in raw hides, forming a stable structure, thereby tanning raw hides into leather (i.e., the "tanning" process), giving leather water-resistant, corrosion-resistant, and flexible properties.

Food Industry

As an antioxidant: Utilizing its reducing properties to delay oxidative deterioration of food (such as oils and fats, fruit juices) and extend shelf life.

As a clarifying agent: Used for the clarification of beer, fruit wine, etc., by binding with proteins in the wine to precipitate and remove turbidity.

Flavor regulator: Imparts an astringent taste in certain beverages (such as tea), while inhibiting microbial growth (natural preservative).

Pharmaceutical Field

Astringent effect: Topical application can treat skin ulcers, burns, eczema, etc., by precipitating proteins to coagulate wound tissue, reduce exudation, stop bleeding, and protect the wound.

Hemostatic effect: Oral administration can be used to treat gastrointestinal bleeding (such as gastric bleeding), functioning by constricting blood vessels and coagulating blood.

Antibacterial and antiviral: Has inhibitory effects on various bacteria (such as E. coli, Staphylococcus aureus) and viruses; its mechanism is related to destroying microbial cell membranes and inhibiting enzyme activity.

Other Industrial Uses

Water treatment: As a chelating agent for heavy metal ions (such as lead, mercury), used in wastewater treatment to remove toxic metals from water.

Dyeing industry: As a mordant, helping dyes fix onto fibers and enhancing color fastness; also used in the preparation of black dyes (reacting with iron salts to generate black complexes).

Adhesives: Reacts with formaldehyde to produce tannin-formaldehyde resin, used for wood adhesives, featuring water and corrosion resistance.

Cosmetics: Added to skincare products, utilizing its astringency to tighten pores and control oil, or as an antioxidant ingredient to delay skin aging.