July 13, 2011

Vegetable Tanning
Sumac:
Today we met with Dr. Frett of UD's school of Agriculture and Natural Resources to discuss natural dyes he is growing. We got to see Japanese Indigo (Polygonum tintorium) and Goldenrod (Solidago). He also gave us two types of sumac, Fragrant Sumac (Rhus aromatica) and Staghorn Sumac (Rhus typhina), that can be used for vegetable tanning. I removed the leaves from some of the sumac and soaked each sumac species' leaves separately in distilled water.

Rhus aromatica:

Rhus typhina:

Oak
The various concentrations of oak bark tannin were left to continue the tanning process.

Alum Tanning
The piece of hide in the alum tanning solution was left to continue tanning.

June 13, 2011

Pickling 

The first test strip was removed from the bating solution and placed in a solution of CH₃COOH (acetic acid) and H₂O with a pH of 4.5 to lower the pH of the hide in preparation for tanning. To create his solution 350 mL of H₂O was mixed with 15 mL of CH₃COOH. The hide remained in this solution for 2 hours. 

Alum Tanning

90 mL of H₂O, 30 g of unbleached flour, 30 g of NaCl, 30 g of KAl(SO₄)₂^.12 H₂O (Alum),  and 15 mL of egg yolk (one egg yolk) were combined to form a paste. 

This solution was applied to the test strip.


Dehairing
The second test strip was removed from liming solution and hair was removed in the same manner as was used for the first test strip.


Soaking 

The second test strip was soaked in water to stop the liming process.


Vegetable Tannins

The oak bark pieces were removed from the solution in which they were soaking.