This article originally appeared in Turkey Red Journal, 2006
We are all familiar with the long and rich legacy indigo brings to the human experience of color in nature. But how many of you, as dyers and as artists, are familiar with painting with indigo? All forms of natural indigo fall into the category of pigment dyes. Pigments are topical dyes, and include most mineral dyes, such as Japanese ganryo (顔料), and naturally sourced paints, such as carmine (cocheneal). By virtue of the fact that they are topical, pigments are very easy to apply in paint form to just about any surface, including textiles. Pigments do require a binder of some sort, which is very different than a mordant, to make them permanently grab hold of your fibers. Iʼll be using soymilk.
The Binder: Soymilk is made from soybeans. Soybeans contain the
highest percentage of protein of all legumes. To make soymilk, simply soak a handful of dry beans in tepid water for about three hours, or until fully swollen. Rinse and place in a blender. Fill the blender 4/5 full of cold water, push the high or liquefy button, and churn until the soybeans appear to be fully mashed.
Froth will form on the surface of the liquid. Pour the contents through a rag and into a bowl. The liquid that flows through the cloth is your soymilk, the crumble left in the rag may be tossed in the garden as compost. The soymilk consistency should be about the same as 2% milk (slightly translucent). Add water to thin if necessary.
The Sizing: I always recommend a layer of soymilk sizing be applied to all weaves before beginning to paint. You may do this with a sponge or a spray bottle, but if you want consistent and streak-free results, I recommend the brush traditionally used for this step, the Japanese jizomebake . Applying soymilk as a sizing will prevent wicking and allow for much richer color, while at the same time reducing crocking.
The Pigment: You will need oxidized indigo. The most accessible source for most of you will be the froth of bubbles that form on the surface of your indigo fermentation vat, the aibana (藍花). This is the reduced indigo that has come into contact with the air and oxidized. Simply scrape it from the surface and use it wet or dry. Another reliable and consistent source is ganryo pigment from Japan made from Japanese indigo. This is basically an indigo lake. You may also make your own indigo pigment as described under Preparing Indigo Pigment from Fresh Leaves and Fermentation.
The Paint: Add a little soymilk to the pigment, and you are ready to paint. Any watercolor brush will do to apply the pigment, as will sponges, crumpled paper, or bare feet. I use Japanese brushes called surikomibake (摺込刷毛) and mensou-fude (面相筆) for most of my work.
From this point on, work with the indigo/soy mixture much as you would paint with watercolors. The sizing will give your weave a stiff, paper-like surface upon which to work. (If properly applied, the stiffness will go away once the work is completed.) Images 1-4 below may help as a rough guide, starting with the lighter shades and working up to the deeper tones as layer upon layer is applied. I tend to work with a moist or nearly dry brush, rather than a wet one.
The Final Steps: The one drawback to using a natural protein is that it requires curing. Curing involves oxidation of the protein, which takes it from a water-soluble protein, to a non-water-soluble protein-polymer. Once cured, the indigo will not crock and will remain washable. It does no good (nor any harm) to steam the dried soymilk. The safest and easiest method is to simply let the fabric sit exposed to warm dry air. I recommend a minimum of four weeks curing for quality work, but some artists will pare this down to just a few days and still have very good results.
Once the soymilk dries you may handle it with ease, even sewing with the fabric if you like. However, it will remain somewhat stiff until you wash it once. Washing does not remove the soymilk, it simply softens the fabric. However it should not be washed before it cures.
Indigo painting may also be combined with vat dyeing and resists. In the figures below I have used rice-paste resist along with multiple dunkings to create my imagery. In both cases, the rice paste has been applied with brushes to mimic a batik-like affect. As a final step I have painted in deeper lines and details with my indigo/soy mixture and a mensou brush (a 00 watercolor brush is a fine substitute).
Old Friends. Vat indigo on Russian linen with detail showing paste highlights applied before dipping and minimal painted indigo details (eyelid).
Equally interesting results may be achieved by combining the painted indigo with tie-dye, shibori. This combination is what is referred to as tsujigahana.