رنگ و رنگرزی

Easy Dyeing, Living Colors

This article appeared in ORR Vol. 13, No. 3A very satisfied and excited Nest Rubio greeted me when I dropped in on her for coffee the other morning.


For a long time now she has been niggled by the generally accepted stories about steaming dye vats. Unimpressed by rug lore, it seemed to her most unlikely that primitive tribes people would have resorted to such processes. Fuel gathering was hard enough, without burning it for anything other than the two essentials of keeping warm and of cooking food.
If her feelings were reasonable, then it had to follow that it must be possible to achieve satisfactory results with water at "domestic" temperature. The countries in which rugs are traditionally made have a very warm climate, so a vat left out in the sun would certainly become pretty hot. Admittedly the process would be slower, but time was never a critical matter for primitive peoples who, in any case, were generally limited to measuring this in days and in lunar months.

 

With this in mind, she experimented with various mordant strengths, various concentrations of dye stuff, various periods of immersion, and various temperatures. Using madder in this way she achieved an incredible range of colors from the softest "decorator" pinks to the deep masculine reds so often found in Turkoman rugs. But her delight arose from the fact that her results could be consistently replicated. Thanks to modern photography and an excellent PC with a DTP program, she has crystallized these into picture and print as you can see. She has provided me with a recipe for cool dyeing with madder root, a card showing the deepening color in 15 individual swatches of natural white wool immersed for increasing periods from half an hour to eight days, and a color photograph showing the consequences of heat to swatches immersed for four different periods of time and at three different temperatures.
The day after she gave me this material, with instructions to tell all and sundry in order that this technique would be incontestably "in the public domain" (and, therefore, not patentable!), I happened on Arthur Upham Pope's obituary of Friedrich Sarre, in which he related a revealing conversation between the great man and one of his students. Briefly, it went like this:
Sarre: Take these notes, you publish them.
Student: But they are yours, not mine.
Sarre: There is no "yours" or "mine." It is for unsere wissenschaft (S.O.P.A., 1981 edition, Vol. XIV).
With this sentiment still echoing in my mind, I hope that you will be able to find room to publish these results at an early date.
Cool Dyeing with Madder Root
Published treatises on dyeing with madder root have all warned the reader of the complexity and critical nature of the process, requiring the wool to be heated to temperatures likely to cause it to felt.
The purpose of this experiment is to discover if it is possible to dye wool to deep brown-red shades without heating the dye pot to temperatures detrimental to the fibre.
Experiment 1
Wool was placed in a cold hard water bath containing Alum mordant in the proportion of 25% Alum to wool by weight and left to soak for 30 days. After removal from the vessel, the wool was rinsed in cold water.
The wool was then placed in a vessel with an equal weight of chopped madder root and water to cover. The vessel was brought up to a temperature of 40 degrees centigrade in this case by simply placing the vessel on the back of an Aga between the hot plates and further insulating the vessel with the appropriate number of pot holders underneath.
Samples of wool were taken from the dye pot on the third, fourth, fifth, and seventh days. The results are shown in
Experiments 2 and 3
If it is possible to achieve such intensity of color within seven days at a temperature of 40 degrees, I was curious to know just how successful it would be at colder temperatures.
Two vessels were prepared, the first at 30 degrees centigrade, a temperature which can be maintained by placing the pot near a radiator, for example. The other pot was left a room temperature, which was a constant 25 degrees centigrade. The results of these experiments show that given enough time, very intense shades of red and red-brown are achievable without any effort or skill involved in the process.


The time comparison to
achieve a similar shade:
3 days at 40 degrees
9 days at 30 degrees
13 days at 25 degrees


Recipe
¼ lb. alum to 1 lb. wool
Place in cold water to cover for 30 days with an occasional prod.
Rinse well and spin.
1 lb. madder root to 1 lb. wool
Place in cold water to cover.
Heat to 40 degrees centigrade and maintain with occasional stir for required time and color intensity.

Take Great Care
Do not use a lid and, as evaporation occurs, add water to keep wool and dyestuffs submerged.

by Jack Haldane

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