1.1 This practice covers the determination of the combined tannin and nonextractable organic resins and the degree of tannage of all types of vegetable-tanned leather and leather with organic retannages. This practice does not apply to wet blue.
====== Significance And Use ======
This practice may be used to determine non-protein or non-nitrogen containing organic matter in leather which is not extractable with water or hexane. Examples would be vegetable tannins and acrylic lubricants.