Discharge eco-printing is a method that has been mostly developed and refined by Irit Dulman. She has some very useful information about this technique on her blog. It is a type of eco-printing where fabric is dyed a solid colour, then leaves are placed on top. When the bundle is cooked, some of the leaf acids and other compounds react with the solid dye and ‘discharge’ it, leaving a leaf print surrounded by colour.
As with other types of eco-printing, most people seem to do discharge printing on wool and silk. But because I prefer using plant-based fibres, I have been experimenting with this technique on cotton. This is my most successful piece so far.
I used logwood dye for the background, which has created a rich earthy purple. And I used 2 varieties of geranium leaves to create the discharge prints.
As you can see in this video, one variety creates far clearer discharge prints than the other. But I am happy with both, because I wasn’t going for an even, uniform appearance with isolated, clear leaf prints. I like the moodiness of this tope, which reminds me of night skies and fireworks and magic.
I am still very new to this technique. But here is what is working best for me so far: First I mordant my fabric with aluminium acetate, then soak it in a warm dye bath until it is the colour I want. I choose a leaf with good discharging potential (Irit Dulman shares many examples of these on her blog). Generally the back of the leaf discharges more, but I like to use both sides and see the different effects. After placing the leaves on the dyed fabric, I fold it up, clamp it between tiles and cook as usual.
I’ve always been told that the mordant for plant based fibers is alum acetate, that alum alone is inadequate. Have you had good results with alum?
That’s just sloppy writing, thanks for catching it Rebecca. I used aluminium acetate for this top. It is my go to for mordanting plant based fibres because it can be used without tannins.