4. Biochromes

Tzachila tribe man from Ecuador dyiening his hair

Light incidence on silk fibers

With light, the innanimate air and water organize to form complex living organisms using a pigment (chrolophyl) trough the photochemichal process of photosyntesis. All living organisms are made of light.

And if there is light, there is color.

From the occtopusses' ink to the color of the butterfly wing, the nature has evolved a great amount of light-interacting molecules, using the colors for communication, protection and photon-electron interaction for molecular synthesis.

With the advance of the modern chemistry, the new technology took over, but the use of fossil fuels and dangerous chemicals then became a problem. Contamination is an issue that now is a common interest for humanity.

With the use of new technology, like Synthetic Biology now we are able to produce already collored yarns. This technology might one they help us with the environment. Here is an interesting articla about it: Psicodelic cotton in the lab.

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In this class we are going to experiment with the extraction of some collored bio-molecules and perform some dyeing tests.

Methodology

We decided to use three kind of tints and dyes: Carrot, Daucus carota subsp. sativus, Achitote Bixa orellana, and Mortiño Vaccinium meridionale.

A carrot is a widespread item that could be found in any kitchen. It is very popular in cotton dyening, and I found the molecule interesting because it is involved in the vision process. It is actually an A vitamin precursor, Retinol.

The achiote plant, is present in a seed from a plant native to amazon rainforests. In my country, an indigenus comunity called Tsáchilas use it to dye their hear and their bodies. Here we use it for cooking. An oil dislolved product can be found in the local market.

Mortiño is a berry related to the Arandano. It grows in the highlands of my country, and it is also used in the local gastronomy. It provides a blood-like color to a tradiitional beberage for the "dia de los muertos" celebration in Ecuador. I was wondering if the collor could be fixed in textiles.

For the textiles to be colored, we used cotton, a mixed fabric coton/synthetic, and raw silk fibers.

For mordant, we used Iron Oxide (FeO), that we made with a rusty objects soaked in water.

Achiote pigment extraction

We measured 12 gr. of Achiote seeds.

And started to ground them using a mortar.

Then we added mineral oil (baby oil), also 12 gr.

We see that the extration is prety staightforward, and ocurs at room temperature. For cooking, we used to rise the temperature, but not so much.

Here we can see the extraction form above.

Carrot pigment extraction

For the carrots, the pigment that we aiming at is the carotenoids. Those compunds are termostable (they resist high and low temperatures), so we used some heat. Again, mineral oil as a solvent.

Grounded and with a little bit of oil, we see that there is not much extraction.

Breaking appart the cells...

We can also see that the color dimmer that the carrot itself.

With some heat, we see some color disolving in the oil.

Finally, we filter the mixture using a coffee filter.

Mortiño

The pigment of this berry comes from the anthocyanin molecule family. It is water soluble, so we used water in the extration. This pigment also blocks ultraviolet radiation, so it is interesting for the protection of this rays, maybe in eyewear resins or other gardments.

Antocyanines have the property of changing colors when their pH environment changes. We can use acids or bases to change the pH, and since, the color. We used the mild Acetic acid, 4% in vinager, and sodium bicarbonate, as a mild base. Sure, we can use stronger acids or bases, but using their simple organic counterparts makes it safer.

Here we can see a drop of our pigment, with one side mixed with acid, and the other with base.

Here we can see it a little closer. The additives changes the color more dramatically in the basic side, that turned in a saturated purpule/blue color.

We had some containers prepared with mordant and tested the pigments in different fabrics.

Here we can see the same pigment, different pH dyening process.

The mordant/water/pigment is necesary in water-soluble pigments, but in the case of carrots or achiote, the oil soluble pigment binds easier with the tisue, with no mordant involved. Here we can see little drops of water with vinager, and we see that they don´t mix, and the pigment is present only in the oily part.

We soaked the tissues in all the pigments.

Filtration can take a little time... be patient.

Using the lab chart we created a chart showing the diferent tones obtained with diferent pH points.

Microscope

I used a hacked microscope I fabricated before. It is just a hacked webcam where the lens is fliped upside down using the same screw. An acrilic base was fabricated for keeping the lens steady.

With the device, we can see here, for example, the ammount of tint that got impregnated on the fabric. Here is a picture with chlrophyle.

And here some silk fibers with side ilumination.

With the light in the right angle, we see that the fibers reflect the light.

With the right program, it is posible to calibrate the picutures against an object we know the meausure of. The program I use is Fiji/ImageJ. Here we can find the instruction of how to calibrate it. We use a known distance, in this case, marks in a caliper.

We set the known distance

Once calibrated we test some measurements. Calibrate like shown here, from the begining of the mark to the begining of the next mark, not as shown in the previous picture.

Then we take some measurements to test. We have it pretty close.

Some pictures taken. Here some sugar crystals.

Of course we can measure them...

We also have some salt chrystals.

Another metal close-up.

We can also make videos and animations. Here we see the silk reaction to diferent light incidences.