Oil tanning

Glycidaldehyde has been used as a cross-linking agent for the finishing of wool, for the oil tanning and fat liquoring of leather and surgical sutures (lARC, 1976). 

Blending only changed TBN and TAN by the ratio of new/used oil, while the base reserve of the new oil had no neutralizing effect on the used oil TAN value. Corrosion tests in a CLR-L-38 engine for the new/used blends of 0/100 and 25/75 showed these to be very corrosive, whereas the 50/50 blend was much more effective at reducing corrosion. The rates of corrosion do not show a linear correlation with either TAN or TBN. 

These should not be confused with oil-tanned skins such as chamois wash-leathers or the buff leathers employed widely by seventeenth century armies to make protective jerkins. These are not impregnated with stable, water-repellent fats but treated with reactive, oxidisible oils, which undergo chemical reactions with the skin during processing to give a proteolytic enzyme-resistant product. 

Oil-tanned chamois leather Alum-tawed skins Formaldehyde-tanned leather Aluminium-tanned skins Vegetable-tanned leather (hydrolysable) Vegetable-tanned leather (condensed) Chrome-tanned leather... 

C16-18 alpha olefin Tetradecene-1 tanning, chamois-leather Cod liver oil tanning, leather... 

Stuffing is one application method and fat liquoring the other. In stuffing, warm mixtures of fats are applied, such as fish oil, tallow and degras, acting as an emulsifier, which derives as a a.m. by-product of oil tanning. 

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