Mordanting is an important step in the natural dyeing process. It is a pre-treatment that facilitates a stronger bond between the fiber and the dye. Soy isn’t actually a mordant but it does act as a binding agent between the fabric and dye. It is one of my favorite methods because it is non-toxic and fairly easy. I like to use soy treated fabrics when I’m dyeing with pink and yellow dyes as it helps the color take on an earthier tone. In this tutorial I will show you how to pre-treat fiber with soy milk.
What you will need:
- Dried soy beans or store bought soy milk
- jar or bowl
- stainless steel pot or plastic bucket
- mesh strainer
- nut milk bag or cheese cloth
- blender
- spoon
- water
Step 1
To pretreat with soy milk you will need to make or buy unsweetened, unflavored soy milk. If you are going to use store bought soy milk, skip ahead to step 4.
I prefer to make soy milk as it is very simple, less wasteful and much more cost effective. To make your own you will need organic dried soy beans, a bowl or jar, water and a blender.
Start by pouring the dried beans in to a bowl or jar and covering with water. I use about half a cup of soy beans to make a 3 gallon bucket of milk. You will want a 2:1 water to bean ratio.
Leave the beans to soak for at least 12 hours. You will notice that they will become plump.
Step 2
Drain and rinse the beans before adding them to the blender with a few cups of water. Blend on high for 1-2 minutes.
Step 3
Strain the solids from the milk by pouring it through a nutmilk bag or a few layers of double cheese cloth. I like to pour over a mesh strainer to catch any spills.
After all of the milk has been strained, I squeeze my nut milk bag to get every last drop of liquid.
Step 4
Now the milk will need to be watered down. If you’re using store bought milk, add about 4 cups of milk for every gallon of water.
I don’t usually measure the amount of water I add at this point. Instead, I just fill the vessel I will use to mordant almost full with water.
Stir well to combine the milk and water.
Hooray! You’ve made soy milk!
Optional Step
At this point, I like to add tannin to my soy milk. It is completely optional but I find that it helps create deeper colors.
My favorite tannin to use is gallnut because it is the clearest tannin.
If you’d like to add tannin to your soy milk follow these simple steps:
- Add a few tablespoons of tannin to a bowl or jar
- Mix with hot water to dissolve
- Mix with cold water to cool
- Mix tannin mixture into soy milk
Step 5
At this point, you can enter your pre-dampened fabric into the soy milk.
Store the milk in a cool place and allow the fabric to soak for at least 12 hours, stirring occasionally.
Step 6
Remove the fabric from the soy milk and wring as much of the milk out as possible. Running the fabric through a spin cycle in the washing machine works well to remove the excess liquid.
Hang or lay flat to dry.
Step 7
When the fabric is dry, dip it into the same soy milk that you previously used. Swoosh it around for a minute or two to make sure that it is evenly coated.
Repeat steps 6 & 7 three or four times. Then, allow the fabric to sit and cure for at least one week before dyeing.
For more information, please check out my self-paced online Natural Dye Course.