Horst Nitz

Lieber Manfred,

thanks for that deep look into the murky abyss of primitive chemical processes from which we have risen to modern clean and pollution free heights. Without those beginnings we would have to do without booze, cornichons, yoghurt, wholemeal bread and sauerkraut. Without the latter and its scorbut preventing properties the Americas would probably never have been discovered, and Turkotek neither. How much poorer the world would be without!

I will definitely add 'exfoliation caused by fermentation' to my selective thesaurus for rug society meetings. However, can you help and boost my self-confidence by explaining to me, whether this process is more important to cold-dying with purple, aubergine etc. or whether it improves fixture of mordants or dyes independent of process temperature?

Regards, Horst

Manfred Bieber

Hi Horst,
Expeditions made by V.G.Moschkova between 1929 to 1945 to the carpet-making peoples in Central Asia document a multitude of old dyeing techniques being applied in these regions. Amongst other things, the following procedure was described: "They cooked millet flour in water, added a handful of alum, let the solution ferment for five days and then immersed the wool yarn in this solution for a period of ten days. It was only then, that madder-dyeing was started."
The results of this kind of fermentation can be traced from Anatolia til Kirgistan. Some hints are given from kirgistan women in 1995 during my visit there.
Regards
Manfred

Horst Nitz

Hi Manfred,

yes I read that in your essay. What I wonder is, whether fermentation increases the contact surface of fibres (like 'sanding') and by that inproves adhesion or bonding of mordants with the result, that - after dying - an altogether more durable or otherwise improved (composite) quality is achieved in comparison with a non fermentation approach; and whether that process may be of particular importance when it comes to cold dying techniques (aubergine) with an (assumed) lesser affinity to the fibre?

Regards, Horst

Manfred Bieber 

Hi Horst,
let us make sauerkraut and red wine in 2 days!
It is not possible.
If people are interested in saturated and long-term stable natural dyes, they must know something about the chemical background:
Mordants:
Alum: KAl(SO4)2 . 12H2O molecular mass: M=474,39g/mol
Ferrous sulphate: FeSO4·7 H2O molecular mass: M=278 g/mol
The most important dyestuffs in madder for red and violet color shades:
Purpurin - molecular formula: C14H8O5 ,molecular mass: M=256,21 g/mol
Pseudopurpurin - molecular formula: C15H8O7, molecular mass: M=300.22 g/mol
These molecular characteristics are important, because the rate of diffusion into the inner
hair structure is very very slow. Therefore fermentation is necessary.
This is explained in my essay.
Pseudopurpurin is decarboxylated in Purpurin in hot dye bathes.
This is the most important aspect concerning fermentation. If you neglect this fact, you cannot achieve violet color shades. (Böhmer-Brüggemann, Schweppe)
Regards
Manfred

Mark Traxler 

Manfred, Thanks for a very interesting artile! I have done natural dyeing for 15 years, but never tried "cold dye" approaches. I have 100 questions! But here is one! I recently acquired a very nice Turkoman textile that has a bit of an issue. The yellow has, in some places but not others, bled slightly into the immediately adjacent wool foundation. The shade of yellow is bright but not garish. It is "clear" and very close to what I have gotten with Osage Orange in my own dye work. I estimate the textile to be at least 100 years old, and likely circa 1875. The yellow pile has mellowed in that time, as one would expect. There is no tip fading. One knowledgeable gentleman I showed the piece to said it appears to be of Igdir origin. Now, how might I go about determining if the yellow dye is natural? Is there a lab I could send fiber to for microscopic or chemical analysis? I would like to know if this is the result of overzealous mordanting [crocking] or dyeing, or, if it is synthetic. Thanks.

Manfred Bieber 

Hi Mark,
would it be possible to send me a picture of your piece?
Regards
Manfred

Mark Traxler 

Manfred: I would love to send you some images, but I don't know how to do so here. I don't have a website to post the image on, from which to put it into a url. My email address is as follows: mtraxler@co.le-sueur.mn.us
Email me and I'll send you some images. Thanks.

Steve Price 

Hi Mark

If you send them to me, I'll put them into our server and you can link them into a message. Everyone else will be able to see them, not only Manfred, of course.

Regards

Steve Price