Vegetable tannage

Vegetable Tannages. Aqueous extracts of barks, leaves, wood, roots and twigs of a large number of vegetable species have been employed to produce... 

Certainly by the classical Greco-Roman period, vegetable tannage had developed into an important craft-based industry and little fundamental change appears to have occurred until the beginning of the nineteenth century. 

Russell, A.E., Shuttleworth, S.G., and Williams-Wynn, D.A., 1968. Mechanism of vegetable tannage. IV. Residual affinity phenomena on solvent extraction of collagen tanned with vegetable extracts and syntans, J. Soc. Leather Trades Chem., 52 220. 

Kedlaya K J, Ramanathan H, Nayudamma V 1971 Mechanism of vegetable tannage. J Am Leather Chem Assoc 66 256-262... 

Russell A E, Shuttleworth S G, Williams-Wynn D A 1967 Further studies on the mechanism of vegetable tannage. Part II. Effect of urea extraction on hydro-thermal stability of leather tanned with a range of organic tanning agents. J Soc Leather Trades Chem 51(6) 222-230... 

White T 1956 The chemical principles of vegetable tannage. J Soc Leather Trades Chem 40 78 - 88... 

The chrome tanning is one step in a compHcated series of leather operations leading from the raw hide to the finished products. Chrome tanning is the most important tannage for all hides except heavy catde hides, which are usually vegetable tanned. In heavy shoe uppers and soles, a chrome tanned leather is frequently given a vegetable retan to produce chrome retan leather. 

The predominant tanning technique in the world is chrome tannage (about 85%). As a multi-purpose material chrome tanned leather can be transferred to leather with different properties (to different leather types) by further processing. However, a significant quantity of vegetable tanned leather is manufactured, too. Part-tanned chrome-free - often termed wet white - leather is also produced, in small but growing quantity. 

Research on the use of condensed tannins in leather manufacture has come to a near standstill in western industrialized countries. Sparrow s fundamental work on condensed tannin-collagen interactions (228) and studies on the combination vegetable-aluminum (110, 226, 234, 241, 242) tannage are important thrusts of current efforts on the use of condensed tannins in leather manufacture. 

The most recent major advance in vegetable tanning processes is the development of a combination vegetable-aluminum tannage (85, 225, 233). Leathers produced with this type of tannage have heat stability even greater than commercial... 

Exner R, Kupka L 1982 Rapid tannage technology for vegetable tanned leather. In Radnotti L (ed) Proc 7th Cong Leather Ind OMIKK-Technoinform, Budapest I(a) 119-130... 

He X-q, Jiang W-q, Li J-z, Lan Z-c 1983 The properties of several commercial vegetable tannin extracts in vegetable-aluminum combination tannage. Chem Ind For Prod 13(2) 1-13... 

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