Creating Dye Baths

Our project goal was to explore the presence of cochineal in manuscripts in the Special collections. Through our research, we learned about the use of cochineal as a dye, paint, and food and beverage colorant. This encouraged us to look deeper into the use of cochineal as a dye, which led us to discovering other natural red dyes such as lac, brazil wood, and madder root. Ultimately, our research encouraged us to start the dyeing process because we wanted to identify, first hand, the pigmentation of cochineal on materials such as cotton and wool, and compare it to the pigmentation of other natural dyes.

We experimented with four different organic red dyes still used to dye fabric. Two of the dye baths are insect based: cochineal and lac. The other two are plant based: madder root and brazil wood. Each dye required a unique preparation and dyeing process with common variables such as weight, time and the addition of chemical alterations.

Cochineal Dye Bath

The cochineal dye bath unexpectedly appeared dark purple throughout the boiling process. The cochineal powder was meant to be boiled four times however we boiled it only three times because the final batch was translucent. We added three grams of cream of tartar prior to adding the fabric which changed the dye bath hue closer to a pink. We added treated cotton, untreated wool and an untreated linen napkin to the dye bath. After soaking overnight, the cotton and wool turned out the same hue of pink however the wool’s color is much more intense. The linen did not take the dye as well and turned out a light pink. After soaking a strip of cotton overnight for the second time, it became a darker hue similar to a salmon color.

Cochineal dyed cotton treated with soda ash, synthrapol, tannin, and alum. Cochineal dyed untreated wool on top. Cream of tartar added to the cochineal dye bath.

Lac Dye Bath

The lac dye bath appeared the closest to a true red out of the four dye baths and without the addition of any chemical alterations. The process has the shortest wait time to add the fabrics. After soaking for approximately 24 hours, the treated cotton and untreated wool both appeared to be a deep pink. After soaking a strip of the cotton overnight for the second time, the hue remained the same but became more intense. 

Lac dyed cotton treated with soda ash, synthrapol, tannin, and alum. Lac dyed untreated wool on top.

Madder Root Dye Bath

The madder dye bath was difficult because it required maintaining a temperature of 140 degrees fahrenheit prior to adding the fabric. It also tended to foam and had a similar consistency to sea foam.  The dye bath appeared to be a lightly concentrated orange throughout the dyeing process. After soaking overnight, the cotton and treated wool both turned out as a bright burnt orange. Variables that may have affected the dye bath include the water temperature, acidity of the water and the ratio of pigment to water. It is possible that the dye turned out more orange than expected because we had difficulty achieving the correct dye bath temperature. After soaking a strip of the cotton overnight for a second time the hue darkened and became more intense.

Madder root dyed cotton treated with soda ash, synthrapol, tannin, and alum. Madder root dyed untreated wool on top.

Brazil Wood Dye Bath

The brazil wood dye bath was the longest process out of the four pigments. The dye bath needed to sit overnight and cool prior to adding fabric which also needed to sit overnight. The dye bath appeared to be a dark fuchsia and the dyed cotton appears to be almost identical in color to the lac dyed cotton. We also added untreated wool to the dye bath on the first day, which became brown.

Brazil wood dyed cotton treated with soda ash, synthrapol, tannin, and alum. Brazil wood dyed untreated wool on top.

Thoughts and Conclusions

After conducting the following dye processes, we have come to several conclusions regarding the color and process of creating each dye bath, and the pigmentation of the fabrics. We hypothesized that all of the dye baths would be similar in color, and would produce varying shades of red. However, all of the dye baths were distinct colors, and none of them achieved a ‘true red’ pigment. Initially, we believed that the cochineal dye would yield a deep red, however its initial appearance was a deep purple, and we added cream of tartar to make a deep red. However, when we dyed the cotton fabric, we ended up with a light pink shade. Both the lac and brazilwood were the most pigmented dyes, and created an almost identical color. This was intriguing considering the fact that lac is a protein, or insect based dye, while brazilwood is a plant, or cellulose based dye. 

Of all the pigments, lac and cochineal, both insect-based dyes, were the easiest to work with and had the most efficient dyeing process. Madder and brazilwood, the plant-based dyes, took the longest to make. When dyeing with brazilwood, the treated cotton became a deep fuschia shade, very similar to lac, yet the untreated wool that we added to the dye bath became a dark brown color. Altogether, all the fabrics that we dyed had color inconsistencies, which is likely due to the fact that the fabric was not fully submerged in the dye bath throughout the duration of the soaking process. However, we did not expect the wool to be so pigmented and evenly dyed, especially due to the fact that we did not prep the material prior to soaking. Lastly, we assumed that if we re-dyed portions of the fabric in the respective dye baths that it would become darker than the original shade, however this  yielded no changes in pigmentation. Altogether the dyeing process was a significant learning curve for us. We now have a better understanding of the natural dyeing process, and we have an improved method on how to approach this in the future.

View the ‘Creating Dye Baths’ and ‘Dyeing Process Photos’ page for more information on our dyeing process.