[Sca-cooks] Re: Indigo

[Wanda Pease]

CIBA Review 85, 1951 " History of Indigo"  CIBA is/was the giant Swiss
Chemical Company (now Ciga/Geigy who make my migraine meds) who make
dyestuffs.

	"In the history of the dyeing industry indigo holds a unique place by
reason of its irresistible rise to supremacy among dyestuffs and its equally
rapid dethronement by the modern chemical colours.  Though well-known to the
craftsmen of antiquity, it was so precious that it remained in rare use even
in the Middle Ages, but the  discovery by Vasco da Gama (1498) of the sea
route to the East Indies and the European settlements in the Antilles and on
the continent of North America put it on the market where it ousted woad,
its most dangerous competitor, only to be in turn defeated by the rapid
advance of the coal-tar colour industry.
	Like woad and the aristocratic purple, to which it is related, indigo is
one of the oldest vat dyes known to the craft having already been employed
in prehistoric days; but it was not till thousands of years later, after the
synthesis of indigo had been established, that it became evident that
indigo, woad and purple were not only closely related in technical respects
but belonged to the same group of dyestuffs.  Both the indigo and woad
plants which yield a blue dye, contain indican, that is to say a kind of
ester or glucose compound of indoxyl and sulpheric acid or glucose
respectively, from which by decomposition indoxyl and then by oxidation
indigo is readily obtained.  The juice extracted from the purple yielding
mollusks, Tyrian purple, with which in ancient times the robes of emperors,
kings and general were dyed, also contains a derivative of indigo, vis.
6-6dibromoindigo (Ciba Review No 4, page 129)
	The sub-continent of India, noted for its age-long dyeing craft, is not
only the home of the indigo plant proper (Indigofera tinctoria, but also the
oldest centre of indigo dyeing in the Old World (cf. page 3088 CIBA Review
#85).  It is believed that indigo first reached the ancient world together
with precious luxury articles imported from the East in the last few
centuries B.C. though the quantities received in the Mediterranean countries
must have been very small on account of the high prices realized.
	Indigo is first mentioned as a paint pigment in Vitruvius' "De
architectura", a work dating from the end of the first century B.C. and
general supposed to be based to a large extent on older Greek Sources..."

..."Realizing the great economic importance of woad, chiefly grown in
southern France, Picardy, Northern Germany and especially in Thuringia and
contributing substantially through taxation to the revenue of their
countries, the princes and Governments prohibited the employment of indigo.
Only in England, where little woad was cultivated, did the introduction of
indigo meet with no resistance; in fact, a Bill passed in 1581 provided
that, for the purpose of dying woolen material black, woad alone or woad and
indigo (nele, alias blew Inde) should be used as a bottoming.  On the
continent of Europe, however, drastic steps were taken to keep the new
dyestuff out, very heavy penalties being announced for instance in France
against defaulting merchants and dyers in answer to the complaints lodged by
the estates of Languedoc in 1598.  In Germany its prohibition was justified
on the grounds that the indigo used by dyers in the orpiment vat (cf. page
3077) was injurious.  Thus the imperial police regulations issued at
Frankfort-on-Main in 1577 referred to 'the recently discovered injurious and
fraudulent, devouring and corrosive colour' as 'the devil's colour' and
instructed all governing bodies to see to it that cloth-dyers in every town
and state should refrain from using it."

It goes on to say that indigo wasn't very popular before da Gama's voyages
because it was terribly expensive and woad, even though it took more of it,
gave much the same result for less.  It was also used as an astringent for
wounds.

I just got a whole load of CIBA Reviews Via ILL and am in the process of
Xeroxing all that appeal to me.

Regina Romsey


> I had thought that Indigo might be of New World origin, but I guess it
> just showed up in the same time frame as a result of the European
> Voyages of Discovery opening up new areas. I'm surprised, since this
> would be one of the few dyes that could be used to create blue colored
> foods according to earlier conversations here, that indigo wasn't
> imported along with the other Asian spices such as pepper.
>
> Stefan
> --------
>