tannic acid; tannin; an organic compound used in tanning leather, making ink, and as an astringent in medicine

tannic acid or related chemical compounds used in tanning hides

to process raw hides or skins into leather using tanning agents

to process and soften animal hides into leather using substances like fish oil or tannins

Material used in the tanning process to make leather soft, such as chromium salts, tannin extracts, or fish oil

to tan skins or hides to produce leather