Removal of bleeding dyes

["Karin von Lerber, Prevart GmbH" <karin.vonlerber@xxxxxxxxxx>]

We are desperately trying to remove blead out dye from over 200 textile
objects
which have suffered water damage during the last years flood in
Switzerland. The textiles have been submerged in dirty, muddy water for
over three days. The salvage took about one day during which time the
textiles were kept wet before they were rinsed thoroughly with tap water
(which looked clean, but considering the circumstances certainly was
not: canalizations run over, mud, leaking oil tanks everywhere, so
probably traces of it in the tapwater, too).
Almost all textiles dated 19th c. and some 18th c. had some dyes
bleeding; mostly red, some purple, the 18th c. some oliv greens). Even
though the textiles were kept wet, these blead dyes could not be rinsed out.
The textiles have been air-dryed (those with bleeding colours between
layers of household paper towels).

Now, a year later, we are beginning to re-rinse those textiles again
that can make it through an other wetting process, in order to remove
remaining dirt.
Together with a student form Cologne, Constanze Zimmer, I am performing
tests right now.
If possible, we would like to remove some of the staining from bleeding
dyes. As far, we think that at least 3 different dyes seem to be
present: acid dyes, direct dyes and alkaline dyes. Most of the textiles
are silk, the 19th c. ones contain some cotton. We have gone through
lots of literature and through the
whole arsenal of solubility testing during the last few days:
water
polar solvents
wetting agents (nonionic, anionic)
salts
complex binders
buffers (acid and alkaline)
and even Sodiumdithionite (with a very bad conciousness...)
all on their own and in combinations.
The rationale behind was to beginn with water as a carrier and play with
polarity, pH, complexbinder, salt content and detergents.

So far, the combination of diluted ammonia (pH 8-9) and EDTA works best.
This meaning that their is a slight hue of red dye on our white
blotter... but lots of red still remaining in the fabric.
Ammonia and Triammoniumcitrate works slightly less. EDTA, Triammonium
citrate and Ammonia also work on their own, but less than in combination.
Blankit IN (Sodiumdithionite) as a reducing agent had only a very slight
effect.

Water, Water Ethanol (both with and without detergent) show no effect at
all, minimally do Sodium sulfite (Glauber's salt) or Sodiumcarbonate
(Soda).

We are now a bit at a loss. Can someone point us to something we missed?
To more literature?
Does somebody have some great tricks up the sleeves?
We are working on a suction disc, with blotting paper and even with
poultices. The choice of application so far did not influence the
solubility results.

Hoping to recieve lots of mails with great  ideas ....


Karin von Lerber and Constanze Zimmer


--
Karin von Lerber
Prevart GmbH
Oberseenerstr. 93
CH-8405 Winterthur
Tel. +41 (0)52-233 12 54
Fax. +41 (0)52-233 12 57
e-mail: karin.vonlerber@xxxxxxxxxx
www.prevart.ch