first: what means "bleeding" exactly? Healthy wool of pH 5,5 will not absorb dyes permanently so no "bleeding" can occur, not from natural dyes, not from synthetic dyes.
But if wool has absorbed acids or alkaline materials it will
uptake dyes, though the fastness grades will be low. But for the
impression of "bleeding" it is enough.
When our natural dye fashion came to Iran they tried the following method: you put undyed washed wool into water, add a lot of fine madder powder and add a lot of lemons and let this "ferment" for about 10 - 14 days. The result is a bright orange. If this is washed with soap it darkens to obtain a deep red shade, but of horrifying light fastness, 1-2 about. One could not use it "normally"... But it shows that madder can "bleed". Let us assume wool yarns have been dyed using very finely ground madder powder ( "rengi pot" in Yomud Turcoman language), a bit washed and then incorporated into some weave.
The weave is finished and washed. It is impossible to remove all the madder with such traditional washing methods within years.
So to decide this question is easy and the thing looks a bit artificial to me: to detect if it contains a synthetic dye use the method that we first introduced into the analysis of natural dyes in 1990, HPLC with Diode Array Detection. You would find traces of dye stuffs down to 5 ng and you could obtain a kind of finger print of the dyeing system. That means: not just what plants and/or synthetic dyes have been used but which methods most
likely had been applied.
To do this one needs access to such analytical instrumentation, a team (one must have reference dyes, done by very experienced natural dyers with a sound scientifical education, plus a creative enterprising analytical chemist to fine tune the eluation methods) - and funds. Because of the lack of funds (carpets are so unimportant!) we could not continue this work in 1990.
What I can tell here without referring to a big amount of chemistry: pieces that seem to be "early" Turcomans (whatever this may mean on an absolute time scale), and we had washed quite some of them with our system, have unavoidably extreme saturated dyes. This is true especially for all madder dyes, not only for reds. In Turcoman materials most of the dyes are madder dyes anyway. The late materials (so late that one has to be careful because synthetic dyes may start to run) have in general a much lighter palette, more pastel, and the number of colours
in most cases is smaller.
So my conclusion is: I would not claim that an early piece cannot show signs of "bleeding". In case of trouble go and have an analysis made. As far as I heard early Turcomans are not that cheap ....
I made much dyeing ( red, blue, yellow, brown ), always without
mordant ( like alun, oxydes, metal, etc.. ), and without heating with a fire.
My teacher was Anne Rieger, a talentuous artisanal and well-known ( not enough ) dye-maker in Paris.
I can testify than the colours are really steady and solid ( I do not know the right word ) : some of them are in my living-room, with the sun, and no changing from ten years...
The way to do it is really fermenting : the receipe ( over there )is good, but the time ( ..n..days ) is not the point.
The point is the pH ( as everybody can see in the most serious books about dyeing ):
- in a first time, it is necessary to get the pH down ( lemon, which is acid, AND fermenting, acid too ), " sufficiently " down. This is the most important. The best way is to mesure it..and, I can say, it is not easy to go down with the madder. The cold is not good too, and the summer is better, ( chemistry is'n'it )
- in a second time, it is necessary, when the wool is coloured, to make it becoming neutral, or a little basic: how ? ...with a base..
Very easy, and probably the old ways of making colours : no special materials, no mordants, no wood to heat, only the summer sun, some water, some ferment, and some time..The base can be found in the ashes ( potters know that).
We nead only a pH meter, or, as the old Japanese for the indigo vats, you can smell and taste with your finger.
Every moment is important for the final colour. Knowledge and experience make different reds, or yellows..
More, the wool do not stay acid, and the mothes do not like basic wool ..!!
It is absolutely necessary to understand ( we are moderns !) than dyeing is a process walking along the pH scale..
After dyeing, the wool is washed hardly, a little or not at all : so, at the first washing of the carpet, it makes different impressions for the cleaner, not for the owner; some colour can vanish in the rinsing water, but not fom the wool itself, and the colour remains.
To believe it, it is necessary to learn and to experiment, even in your kitchen.
The cultural problem is that modern people do not like fermenting ( forgetting wine, beer, bread , sauerkrout , vegetables in the whole world, ), one of the best ways to conserve food with vitamins etc.. Thr reason is perhaps the strong smell, from time to time ( smell, a work for Steve ? ).
I am really interested about dyeing facts by fermenting in the whole world. ( Except indigo blue which everybody knows ).If somebody is interested...
>The purple making is presumed lost after 1453 ( falling of Constantinople ), but, perhaps some
> Ladik ( Istambul museum near the old race-course ) have some : a kind of red >brownish, that you
> can see , easily on egyptian christian textiles ( copts ), and testified by >mass- spectrography.
> Sometimes madder + indigo, sometimes purple.
That there is antique purple on a "Ladik" (quite late regional commercial carpets) I would question but do not know of any test for that.
> Probably the 30 % is true, ( it looks like my experience with other plants ) and I guess there was a
> way to make it in a good fast..
> And it is not sure at all, than an extract can make it in 2 hours."
It is sure and it is tested for light fastness. Write to the producer of the extracts,
nig Nahrungs-Ingenieurtechnik GmbH , Mr. Axel Wähling , Wasserkunststr. 26 , D-39124 Magdeburg , firstname.lastname@example.org
may be they have a little bottle of Cehri extract for you to test. If you heat you will have in 2 hours for what would need many days of fermentation.
>To prepare an indigo vat, which is a tipycal ( alkaline ) fermenting type, well known all
>over the world, it is necessary to have some time, in a few days,and much more than 2 h.
I did not claim that. But if one uses woad as an auxilliary one can speed up the process
without lowering the resulting coloristic quality. The opposite is true. Fermentation is not the
point. It is one of several possible tools and most likely not the best.
> - 1 the old good ( and bad ) colours were made with natural plants ( good means for me : >old
> carpets, and old tapestries, before the 16 th century and before 17 th century, Colbert in >France ) . > Certain.
Yes, they started to use cheap imported tropical "dye woods" to speed up the process on the expense of quality.
> 2 the actual attempts to make it again , are , very often unsuccessfull ( mickaël ' s facts ) or > make a > colour of " ridiculous light fastness ". Certain.
About the reasons I have written enough, I guess. That has nothing to do with "fermentation" against "science".
> the chemists can make very good colours, in a cheaper way, and, even , very fast and >strong
> yellow especially, by contrast with natural ). Certain .
One should not compare apples and potatoes and must look at the whole process: sustainability, water ressources, environmental pollution, health problems - then new natural dyes have a clear lead. - If one would admit the ultra-toxic potassium bichromate to the application of natural dye plant dye stuffs that would enhance their light fastness dramatically - and some hobby dyeing books recommend that. We don't.
> there is no explanation or recipe to make strong colours with natural plants, even by
> chemists ( or, tell me , I except the blue). Certain (?)
Absolutely wrong. With red on wool up to light fastness 7, on cotton and linen the same,
aubergine from madder similar, yellow 6-7 even on linen. Correspond with
Sächsisches Textilforschungsinstitut e.V. Annaberger Str. 240 D-09125 Chemnitz
Mrs. Brochmann , 0371 52 74 153 Fax , + 52 74 225 Tel.
Ask her what light fastness results of natural dyes she has in her archives of testing results !
In addition ask Axel Wähling from nig.
> 5 some funny people - unscientific or so presumed - claim that they can do it by a good
> processing of fermentation..
Of course this is possible and we have done it often. The process is more tricky than with madder, then. Since many years we use "fermentation" dyeing in educating people to make natural dyes.
It may work for many dyes that one can find in antique pieces, not for all. As far as I can see there is no unsolved secret left in that.
>So, why not test it, and try to improve it, with the means of chemistry ?
May be you do have not heard of it but this is already done. Today there are marketing problems to be solved for that, but no serious technological problems left. But even when working with extracts one has to learn this work seriously - and that does not fit into the backward socio-cultural structure of the Oriental carpet producers subculture. They still dream to get the desired results by cheap labour to whome they give recipes that smart guys could steal from some fools. If not, as they did not succeed, they close the gap by cheating and chemical washing.
In an ecological sense extract making is much more favourable than fermenting but this is not the place to explain it. That would require an extra essay on another topic.
>For exemple, making wine is a very old natural process which has been very much
>improved by wine-chemistry. Is'nt it ?
Dear Philippe, apparently you do not know but some months age there was here a discussion about "carpets and wine" where these quality problems of modern carpeting have been discussed. I can mail to you the archive if you like. Editorial Note: That Salon and its discussion are in the Archived Salons, accessible through our Home Page or through a link in the text header on our Discussion Boards.
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