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Natural Dyes:
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The science and practice of dyeing involves in most cases synthetic dyes being applied in acid baths to various different types of fabrics while submerged in an acid bath. In natural dyeing fabric is mordants (has mordants applied to it) then is submerged in a bath of dye and salt. The mordant and the salt serve A) to hold the type of dye and B) to give each dye its unique color on the fabric.
Purpose
The purpose of this project is to determine the effects of aluminum potassium sulfate (AlKSO4), cupric sulfate (CuSO4), and stannous chloride (SnCl2) on dyeing with madder and cochineal. The three chemicals are all mordants which aide in the coloration and dye fixation of natural dyeing.
Factors
Supplies
Madder root (above) and dried cochineal (below)
Above: Diagram of cochineal bugs, female (left) and male (right)
Below: Cochineal bugs on a cactus ready to be harvested
History of Dyeing
The use of naturally occurring elements and dyes dates back to at least 30000BC when burial mounds were tinted with red ochre and to 15000BC when mineral dyes/pigments were used to produce cave paintings. While the actual date for the first textile dyeing is unknown, textile work began in Mexico around 5000BC; some of the dyes used at this period stayed in use until the beginning of the twentieth century. The earliest known dyeing utilizing complicated procedures dates to around 3000BC in India, where dye production became the most advanced of the ancient world due in large part to close access to dyes, mordants, cotton, and a relatively large work force to handle the dyeing process. Dyeing however was prevalent elsewhere during ancient history. The Phoenicians, for instance, established a Tyrian purple dye factory in Tyre around 1500BC. On the European continent the Venetians and the Tuscans were hailed as the leading dyers well into the sixteenth century. The textile guilds of the medieval era kept much of their knowledge secret and rarely wrote anything down. The oldest surviving dye manual dates from the sixteenth century in Germany followed by the influential Plichto published by the Venetian dyer Rosetti in 1548. The end of mass natural dyeing began in 1856 when English chemist William Henry Perkin accidentally discovered mauve. Indigo, however, has remained in constant use.
History of Madder
Madder (Rubia tinctorum) is a weak stalk plant mainly cultivated in the Netherlands, France, Turkey, Belgium, Germany, Italy, and North and South America. The stalks optimally contain 1.9 percent of the dyestuffs and the overall quality of the dye depends on the soil in which the madder was grown, with the finest quality coming from calcareous soil. Dye extracted from madder produces no lasting effect unless the fabric has first been treated with a mordant; for madder this was usually pure alum. Madder is first referenced around 3000BC in India’s Indus River Valley; the Greek physician Herodotus noted its use in Greece in 450BC; the Jewish Talmud allowed for the production of madder for personal use only; and Pliny the Elder noted that madder was used in Roman dyeing facilities. In the seventh century AD madder use was first recorded at the Abbey of Saint Denis near Paris and in the late eighth century madder was ordered grown on Charlemagne’s land. By the late fifteenth century the town of Goes in the Netherlands had the most advanced madder producing facilities in Europe. It would be nearly 1624 until madder made its way to Britain and this was only by way of France where madder had become a largely dominant agricultural venture. Historically, the most popular color produced by madder was Turkey Red which was developed in India and exported via Western European merchants to mainland Europe. The first actual European operation producing Turkey Red was founded by the French at Rouen with the aide of Greek workers in 1747. During the early nineteenth century a French export of madder totaled nearly £1,200,000 ($2,400,000), but in 1869 alizarin, the synthetic alternative to madder, was introduced devastating the madder industry.
History of Cochineal
The first use of the cochineal bugs as dye was by the Mayan and Aztec peoples. In the Aztec empire cities paid an annual tribute of bags of cochineal dye. When the colonization of Mexico got under way, cochineal became the second most profitable export after silver. Soon Spain held a monopoly on the highly desired dye, but this also created a hardship for the British textile industry at the time. In 1777, a Frenchman snuck cactus pads bearing live cochineal bugs into Haiti from whence they were shipped to France, Portugal, and their respective colonies. In the middle of the 19th century the synthetic dye alizarin also began to replace cochineal in the dyeing market. In recent years cochineal has begun to be used as a natural, “artificial” dye in commercial foods given that it is nontoxic.
Hypothesis
Cochineal: The NaCl swatches will remain unchanged while the other three swatches will be varying shades of red.
Madder: Again the NaCl swatches will remain unchanged, the SnCl2 and the CuSO4 swatches will form a brown color, and the AlKSO4 swatches will produce a reddish brown.
Preparing the Fabric Swatches
Extracting the Dye
Dyeing the Fabric
Mordanting |
SnCl2: cloudy; milky appearance
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Extracting the Dye |
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Dyeing with Cochineal |
95mL H2O in SnCl2
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Dyeing with Madder |
NaCl: 70mL
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Dyeing with Cochineal II |
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Dyeing with Madder II |
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L*a*b Values
Cochineal: NaCl (left) and SnCl2 (left)
Cochineal: AlKSO4 (left) and CuSO4 (righ)
Madder: SnCl2 (left) and NaCl (right)
Madder: CuSO4 (left) and AlKSO4 (right)
Cochineal Trial I |
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NaCl (1) |
L: 75.09 |
NaCl (2) |
L: 66.17 |
SnCl2 |
L: 45.75 |
AlKSO4 |
L: 43.57 |
CuSO4 |
L: 58.59 |
Cochineal Trial II |
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NaCl (1) |
L: 64.57 |
NaCl (2) |
L: 71.62 |
SnCl2 |
L: 40.30 |
AlKSO4 |
L: 41.84 |
CuSO4 |
L: 56.95 |
Madder Trial I |
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NaCl |
L: 75.61 |
SnCl2 |
L: 75.61 |
AlKSO4 |
L: 74.81 |
CuSO4 |
L: 75.02 |
Madder Trial II |
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NaCl |
L: 75.71 |
SnCl2 |
L: 67.18 |
AlKSO4 |
L: 72.18 |
CuSO4 |
L: 73.91 |
Analysis of L*a*b values and physical results
Cochineal |
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NaCl (1-1) |
Due to an unknown circumstance both trials with the NaCl and cochineal produced swatches with two different colors. The values put it near the origin with a relatively neutral “a” and “b” values (4.22 and 6.39). The hue swings far to 75.09 giving it a greenish cast. |
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NaCl (1-2) |
These values put the second color about 16 units away from the origin, but very close to the x-axis. The appearance of the swatch has a reddish cast, but computer-generated images show more a green cast for these values. This second color was much more to the red with an “a” value of 15.97 almost 12 units more than NaCl (1-1)’s value of 4.22. The hue is also largely different as here the “L” value is 66.17 while it is 75.09 in the NaCl (1-1). |
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NaCl (2-1) |
This sample most mirrors the NaCl (1-2) in appearance and values with changes of only 2 units on the “L” and “a” values and no change on the “b” value. Again it is quite a bit off the other parts of the swatch. |
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NaCl (2-2) |
This sample mirrors the NaCl (1-1) in appearance and values, but with higher “a” and “b” values and a lower “L” value. It is unclear what A) caused the different colors on each swatch and B) what caused such varying colors in each trial. |
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SnCl2 (1) |
The values place this sample in the first quadrant with a large amount of red (R = 179) and equal amounts of green and blue (G = 69). Of the four samples of NaCl, the average “a” value was 11.80, therefore this sample’s “a” value was nearly 36 units more. |
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SnCl2 (2) |
By far this sample produced the best red coming very close to the red used by the British during the Revolutionary War. With values of R = 164, B = 50, and G = 45, there is do doubt that red is dominant. The L*a*b values put it well into the first quadrant. |
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AlKSO4 (1) |
This sample was more to the violet shades with values that put it in the fourth quadrant. The dominant color is red (R = 123) with blue as a close second (B = 111). The “a” value was again higher than the “a” is NaCl, but was 26 units lower than the SnCl2. The “b” value in this sample was the lowest yet at -9.60.
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This sample was a deep violet with the lowest “b” value (b = -9.86) of any of the samples. The two samples were very close in regard to their L*a*b values and similar in regards to their RGB values, but in this sample the RGB values are lower. |
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CuSO4 (1) |
This sample was a paler violet with values in the fourth quadrant. The “L” value was higher than the SnCl2 and CuSO4, and the “b” value was higher than the AlSO4, but the “a” value was lower than the AlKSO4. There was no truly dominant color with the RGB values within several units of each other. |
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CuSO4 (2) |
This sample was a lighter shade of purple than the AlKSO4 with the “L” values to prove it (this sample had L = 56.95). With regards to the RGB values, the red is still dominant (R = 142), but surprising there is a fair amount of green (G = 122). |
Madder |
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NaCl (1) |
The values put it near the origin and the physical appearance is of a flesh tone (about the same as the original fabric). The RGB values are all relatively high given the position of the point near the origin. |
NaCl (2) |
This sample was slightly higher up from the
origin (28 units up) and had a more dominant red value on the RGB scale |
SnCl2 (1) |
This sample was only slightly different from the two NaCl samples with RGB values of R = 200 and G = 178. The L*a*b values put the point 23 units up from the origin. |
SnCl2 (2) |
This sample was by far the best produced
with the madder as it was a duller orange-yellow. The values put it solidly
in the first quadrant and the RGB values demonstrated a strong red dominance
(R = 192) while green and blue were lower (G = 146 and |
AlKSO4 (1) |
This sample again returns to what became a normal pattern among the madder-dyed swatches, the retention of the original fabric color with hints of a flesh tone. In comparison to the NaCl samples it showed both higher “a” and “b” values, but inconclusive changes in values on the RGB scale. |
AlKSO4 (2) |
This sample exhibited a hue just slightly darker than the NaCl (2) sample with “L” and “a” values being higher than the AlKSO4 (1). In respect to the RGB values the red was dominant (R = 196) with green as a close second (G = 162). |
CuSO4 (1) |
This sample demonstrated values very similar to the NaCl (1) sample meaning that little or no dye affixed to the swatch. Red was still dominant with green as the usual second. |
CuSO4 (2) |
This sample was almost completely the same as the CuSO4 (1) in L*a*b and RGB values. Even in physical appearance there is no discernable difference. |
Cochineal: The cochineal produced a very good red on the SnCl2 swatch; this red is within a close margin of error to that used in 18th British uniforms and was actually a bit more brilliant than the duller Turkey red used mainly in the western areas of the British colonies at the same period. Surprisingly the AlKSO4 and the CuSO4 produced two shades of violet. The AlKSO4 violet reminded me of colors in royal vestments from this same time period.
Madder: From the stand point of my hypothesis the madder was a complete and utter failure. Some sources stated that the madder should have produced a brown or dull orange, but with the exception of the SnCl2 (2) swatch, none even came close. The original swatches were off white and most remained very close to this color even after dyeing. Some of the minimal dyeing that occurred produced colors mirroring the color of the lapels of the regimental coats of George Washington’s personal guards. These similarities however seem to only be coincidences rather than by the use of historical methods.
Changes: In my original proposal I stated that I would use Brazil wood as well, however due to cost and time I chose to use only two dyes. Another major difference is that I chose to mordant the fabric before putting them in the dye baths; this came from additional research into proper natural dyeing. Several different measurements (ie. mL of water) were changed on a case by case basis as I worked in the lab, but these changes were applied to the entire experiment to retain the original set of variables.
Earth Hues Natural Dyes http://www.earthues.com/ (source of the madder and cochineal used in this experiment)
Liles, J. N. The Art and Craft of Natural Dyeing: Traditional Recipes
for Modern Use. 1990
Roberts, George A. F. and Wood, Frances A. “Chapter 15: Natural Fibers
and Dyes.” The Cultural History of Plants. 2005.
“Cochineal.” Wikipedia. Retrieved from http://en.wikipedia.org/wiki/Cochineal on
30 April 2007.
“Red Scales in the Sunset.” The University of California at Los Angeles.
Retrived from http://www.botgard.ucla.edu/html/botanytextbooks/economicbotany/Cochineal/index.html on
30 April 2007.
A warm and hearty thanks to:
Stuart Leonard for both handling the ordering of the cochineal and madder and putting up with all my stupid questions.
Carol LeBaron for entertaining my questions on dyeing before I had even really started researching what would become my project.
