indigio dye discussion

[J.H.Berger]

Fellows,
I have read several times about the greenish tint in original civil War uniforms and that there is the theory that this is due to some chemicals applied to the cloth after the war for storage reasons etc.
Well right now I have found a man here in Germany who is dying fabric with plant dyes for historically correct fabrics. He has told me that a greenish tint in indigo dyed fabrics is and idication that "Saxon Blue" was used. Saxon blue was invented in 1740 by Barth in Grossenhain/ Saxony.
It is indigo powder dissolved in smoking sulphuric acid (98%). This indigopaste is like a concentrate.
Browsing the net I found some more people dyeing wool and linen with this material and all tell about the greenish / turqoise tint to it in the lighter blue shades.
I thought this could bring some more info in the discussion about the greenish tint of some US uniforms.

[wade03]

Re: indigio dye discussion

Interesting. Also in a conversation with Mr. Tart he was talking about that greenish color being the result of white wool being dyed indigo and then the white wool yellowing over time which makes it green. Makes a lot of sense, but i'm sure that there were many variations in this process.

[Stonewall_Greyfox]

Re: indigio dye discussion

Perhaps Mrs. Lawson might provide some insight, as she has quite a bit of experience in this subject...

Paul B.

[Pvt Schnapps]

Re: indigio dye discussion

Jan, could you ask your friend about red tints in indigo-dyed fabric?

We often hear that only cheap Pakistani import coats fade to purple. But I have a sack coat from a well-known maker that after several years began to take on a reddish hue. Red also shows up in an old forage cap that I have, again from a respectable maker.

In both cases I felt a bit cheated, but then I came across this description of a soldier (a nine-month volunteer) in Red Tape and Pigeon Hole Generals (first published in 1864):

"One would scarcely have recognized in the rough sunburned countenance, surmounted by a closely fitting cap, once blue but now almost red, and not from the blood of any battle-field -- in the course [sic] slovenly worn blue blouse pantaloons, unevenly suspended, and wide unblacked army shoes the well dressed, graceful, accomplished student that commended himself to almost universal admiration among the young ladies of his acquaintance."

To me this clearly describes an article of army clothing that has faded in use to just the color that we now think of as inauthentic. Do you think your friend can tell us what happened?

Thanks!

[LibertyHallVols]

Re: indigio dye discussion

Jan,
Any word if there is a subsequent neutralization of that mixture prior to applying the dye to a fabric? Concentrated sulfuric acid burns like a mutha and has left many a hole in shirts that I've owned.

A neutralization might also shed some light on the resulting color of the fabric.

Thanks!

[Secesh]

Re: indigio dye discussion

I recall a trip 25 plus years ago to Yosemite, during which they had a display of military items from the late 19th century ( 1878 - 1883) commemorating the Army's survey of the Yosemite Valley...One of the kepi's displayed had also faded to a reddish tint...Thanks.

[J.H.Berger]

Re: indigio dye discussion

Well the fabric can be stained first . The indigo paste is dissolved in water. I do not know if it is neutralized by another chamical or just thinned by the water. The dye man has not used Saxon Blue yet but we might experiment as the flannel he has just dyed with the normal indigo vat was too light. It was not sky blue but a pretty light dark blue.

[10TnVI]

Re: indigio dye discussion

FYi- the following is taken from the Scientific American, Vol 10 issue 24, 1855.
Beginning with Vol. 10, issue 16-dec. 30 1854 they ran a seris of articles on dying. issues 23-25 discuss indigo dying. The entire series is avialable at the Cornell Making of America site-along with numerous other periodicals and books of the period.

The Art of DyeingNo. 9~ THE PASTEL VATThe following is taken from Dumas lecture on dyeing, describing the pastel vat. Various substances are em- ployed for dyeing blue in vats, but, after all, indigo is the main one. /The first care of the dyer in preparing the vat should be to furnish the bath with matters capable of combining with tbe oxy- gen, whether directly or indirectly, and of giving hydrogen to the indigo. We must, however, be carefnl to employ those sub- stances only whieb are incapable of imparting to the bath a color which might prove injurious to the indigo. These advantages are found in pastel, woad, and madder. This latter substance furnishes a violet tint when I brought in contact with an alkali, and by the addition of indigo it yields a still deeper shade. The pastel vat, when prepared on a large scale, ordinarily contains from 18 to 22 lbs. of indigo; II lbs. of madder would suffice for this proportion, but we must also bear in mind the large quantity of water which we have to charge with oxydizable matters. I have invariably seen the best results from employing 22 lb~. to a vat of this size. Bran is apt to excite the lactic fermentation in the bath, and should thereibre not be employed in too large a quantity ; 7 to 9 lbs. will be found amply sufficient. Weld is rich in oxydizable principles; it turns sour, and passes into the putrid fermentation with facility. Some dyers use it very freely ; but ordinarily we employ in this bath an equal quantity of it to that of the bran. Sometimes weld is not added at all. In most dye-houses the pastel is pounded before introducing it into the vat. Some practical men, however, maintain that this operation is injurious, and that it interferes with its durability. This is an opinion which deserves attention. The effect of the pastel, when reduced to a coarse powder, is more uniform; but this state of division must render its alterations more rapid. When the bath has undergone the necessary ebullition, the pastel should be introduced into the vat, the liquor decanted, and, at the same time. 7 er 8 lbs. of lime added, so as to form an alkaline lye which shall hold the indigo in solution. Some thick coverings are to be spread over the vat, so as to preserve it from contact with the atmosphere. After this lapse of time, it is to be again stirred. The bath at this moment presents no decided character; it has the peculiar odor of the vegetables which it holds in digestion; its color is of a yellowish-brown. Ordinarily, at the end of twenty-four hours, sometimes even after fifteen or sixteen, the fermentative process is well marked. The odor becomes ammoniacal, at the same time that it retains the peculiar smell of the pastel. The bath, hitherto of a brown color, now assumes a decided yellowish-red tint. A blue froth, which results from the newly liberated indigo of the pastel, floats on the liquor as a thick scum, being composed of small blue bubbles, which are closely agglomerated together. A brilliant pellicle covers the bath, and beneath some blue or almost black veins, owing to the indigo of the pastel which rises towards the surface. If the liquor be now agitated with a switch, the small quantity of indigo which is evolved floats to the top of the bath. On exposing a few drops of this mixture to the air, the golden yellow color quickly dis appears, and is replaced by the blue tint of the indigo. This phenomenon is due to the absorption of the oxygen of the air by the indigogen from the pastel; in this state we might even dye wool with it without any further addi- tion of indigo; but the colors which it fur nishes are devoid of brilliancy and vivacity of tone, at the same time the bath becomes quickly exhausted. The signs above described, announce, in a most indubitable manner, that fermentation is established, and that the vat has now the power of furnishing to the indigo the hydro- gen which is required to render it soluble that contained in the pastel having been al- ~eady taken up; this, then, is the propermo. meat for adding the indigo, which should be previously ground in a mill. The ordinary guide of the dyer is the odor, which, acoording to circumstances, becomes more or less ammoniacal. The vat is said to be either soft or harsh; if soft, a little more lime should be added to it. The fresh vat is always soft; it exhales a feeble ammoniacal odor, accompanied with the peculiar smell of the pastel; we must, therefore, add lime to it along with the indigo; we usually employ from five to six pounds, and, after having stirred the vat, it is to be covered over. The indigo, being incapable of solution except by its combination with hydro- gen, gives no sign of being dissolved until it has remained a certain time in the bath. The hard indigoes, as those of Java, require at least eight or nine hours, whilst those of Bengal do not need more than six hours, for their solution. The vat should be examined three hours after adding the indigo; the odor is by this time weakened; we must now add a further quantity of lime, sometimes less, but generally about equal in amount to the first portion; it is then to be covered over again, and set aside for three hours. After this lapse of time, the bath will be found covered with an abundant froth and a very marked copper-colored pellicle; the veins which float upon its surface are larger and more marked than they were previously; the liquor becomes of a deep yellowish-red color. On dipping the rake into the bath, and allowing the liquid to run off at the edge, its color, if viewed against the light, is of a strongly-marked emerald green, which gradually disappears, in proportion as the indigo absorbs oxygen, and leaves in its place a mere drop rendered opaque by the blue color of the indigo. The odor of the vat at this instant is strongly ammoniacal we find in it, also, the peculiar scent of the pastel. When we discover a marked character of this kind in the newly formed vat, we may without fear plunge in the stuff in-tended to be dyed; but the tints given dur- ng the first workiig of the vat are never so brilliant as those subsequently formed; this is owing to the yellow coloring matters of the pastel, which, aided by the beat, become fixed on the wool at the same time as the in- digo, and thus give to it a greenish tint. This accident is common both with the pastel and the woad vats; it is, however, less marked in the latter. When the stuff or cloth has been immersed for an hour in the vat it should be with- drawn ; it would, in fact, be useless to leave it there for a longer time, inasmuch as it could absorb no more of the coloring princi- ple. It is, therefore; to be taken from the bath and hung up to dry, when the indigo, by attracting oxygen, will become insoluble and acquire a blue color. Then we may re- plunge the stuff in the vat, and the shade will immediately assume a deeper tint, ow- ing to renewed absorption of indigo by the wool. By repeating these operations, we succeed in giving very deep shades. We must not, however, imagine that the cloib seizes only on that portion of indigo con- tained in the liquor required to soakit. Far from such being the case, experience shows hat, during its stay in the bath, it appropri- ates to itself, within certain limits, a gradu ally increasing quantity of indigo. We have here, then, an action of affinity, or, perhaps, a consequence of porosity on the part of the wool itself.

Any wierdness in spelling/grammar is caused by the program the site uses to convert from scanned image to text image-

[Curt Schmidt]

Re: indigio dye discussion

Hallo

Indigo is complicated, because of the nature of the dyestuff and because a great deal of the dyeing was "arcane science and craft" kept in the head of the various dyers.

I hyng aorund indigo dyers for the 18th century and watched many a "blue pot" a-brewin'.

Indigo is insoluable in water before dyeing, and has to be made soluable in the dye vat. Plus,, it requires oxidation to turn blue, which takes place when the fabric is removed from the vat/dye batch and exposed to air.

When looking at 18th and 19th century dye instructions there are a variety of recipes. There were additives put in to combine with the indigo to reduce it and make it soluable in alkali solutions and so in a dissolved state could be absorbed by the fabric.

One method was to add bran and madder (madder being a red dye) or even beer malt to act as a fermentation agent. Other recipes called for copperas.
Then the indigo was dissolved in an alkali solution of say lime, pearlash, sulfuric acid, potash, soda, alum, tartar, or urine.

Dyers talk about the dyebath being yellow, and a layer of green under the first surface of the liquor.

Woad, and/or Saxon Blue ("Chemie," indigo sulfate) was also sometimes added to the indigo.
"Chemie" is said in any 1869 acocunt to have been discovered by an 18th century Saxon named Seidelman who combined sulfuric acid with powered indigo which made a black paste. Frustrated at the waste of expensive indigo, he got made and tossed the pot out the window into the snow.
There he saw the snow turn a nice blue. He collected what was left, added hot water and alum, and test dyed some wool yarn to make the "new color."
He later sold the recipe to the English for $6,000.

Saxon Blue was considered n inferior dye, and it along with mordanted logwood was used to "stretch" indigo dyebaths or as a cheap substitute for the expensive indigo through the 19th century and into the 20th.

So, yes, at any rate, depending on the recipe, skill, purity of dye stuffs, concentration in the vat, temperature, heat, timing, and nature of the wool, etc., etc., the "indigo" dyed stuff could even start greenish. And with the madder, and the dyer's eye as to how much "red" is actually perceived in the color "blue,"
madder can impart a shift to the eye that blue has a slight "reddish" quality.

I am reminded of the Civil War story of the 7th Ohio Infantry who were initially issued dark blue pants that had been redyed to appear sky-blue. However, it gave them a greenish cast that the men fussed about.
And unrelated when the 7th OVI was recreated for the N-SSA, its modern members went to modern green work pants in misunderstanding.

Years ago, "Goldfarb" was offering federal fatigue blouses in simulated indigo that emulateld the ever-so-slight "red" cast blue.

And a not so odd reflection on indigo... A few years ago an excavation at colonial Williamsburg was done of an early 1760's well outside of a tavern that had fallen into disuse and was used as a trash pit.
At the bottom of the former well, still wet and soggy, was a section of indigo dyed spriped blanket.
The anerobic environment of the wet clays had the blanket looking mucky, but when the blanket was unearthed and exposed to air, the indigo reoxidized and turned... blue.

Curt
Who once examined a high priced forage cap at a CW show being sold as a Berdan Sharpshooter cap. It was greenish. But it was blue undereneath where the sun didn't shine Mess

[Becky Morgan]

Re: indigio dye discussion

Non-period warning, but possibly related: Dad's pre-WWII peacoat lining has turned a strange mauve in several places. While he was alive, he assured me that it had been dark blue to begin with and that the color shift occurred after the coat's long soak in salt water. The navy blue wool itself doesn't appear to have changed color except in a few small spots along the seam allowances inside, so it can't have been light exposure that caused the change.

[Curt Schmidt]

Re: indigio dye discussion

Hallo!

Likely a salt reaction to the aniline dyed blue, I would guess.

Salt reactions can be pesky.

I am reminded of the authentic-minded search for proper Berdan "green" material and uniform coats that led to a famous lad producing some that alas, when worn...

Sweat changed the green to orange much to the dismay of the wearers.

Curt

[Spinster]

Re: indigio dye discussion

Becky,

Both salt water and sweat can cause the color leaching you are seeing on the peacoat. Indigo behaves differently on different fibers, be they protein based (silk), bast (linen, hemp) or cellulose.

Curt has covered well the various factors in indigo dyeing, as well as the possibilty of 're-reduction' of the indigo back into solution under certain chemical situations.

Fermentation reduction processes can be set up in a number of ways, and those ways affect color. The bacterial qualities of the madder root aids especially in producing a fine fermentation vat with red undertones. In a different chemical combination, madder produces one of the British Redcoat Reds--- that of the enlisted man, as the officers coats were dyed with the more expensive, redder, cochineal.

Instinctively, when I first started dyeing on any scale, I started feeding one pot into another, conserving water and mordant, and see a good bit of variation in color tone. Dyeing on a small scale(wash pots instead of vats larger than a bathtub) can exacerbate the effects of any abberation in the particular indigo used.

Depending on fiber dyed, various aids are used to protect the fiber-- one receipt I use frequently calls for hide glue in the bath to protect wool from a lye component in the bath.

I work most frequently with urine based indigo vats, and can discern a tonal difference when I get urine in quanity from drinking men (French Marines in a 1740 barracks, with a diet heavy in yeast bread, ale and wine), use a chemical urea, or my own collected over a period of time. Some unusually brilliant blues came when I was still an uncontrolled diabetic, as the excessive sugar fed the fermentation.

Good working knowledge of basic chemistry is vital to all this process---that's the 'science' part of this. But all the organic factors intervening change the color tone as well.

One excellent 1861 sulfuric based receipt calls for an iron pot and a cannonball, securing the pot opening with paper and string, then rolling the pot carefully to use the ball to grind the indigo, then carefully adding the sulfuric to complete the SaxonBlue process. The resulting paste is then extremely diluted in the dyebath. It's no more or less dangerous than the lye component in a urine based dyebath. Every dyer ought to participate in this process ...........Once. Me, I'll take the lyebath every time.