Oogst – Indigo

Description

Indigo (Indigofera tinctoria) Indigo(E)
Paints: shades of blue
Grand complexion
fairing dye

Indigo has been used for thousands of years to dye various fibers in the most beautiful shades of blue. In the past, woad (Isatis tinctoria) was grown in the Netherlands to make blue dye, but in the 16th century the woad was supplanted by indigo from the Dutch East Indies and other Asian countries.
The indigo dye is extracted from the fresh indigo leaves and the resulting indigo cake is processed into powder and used to make the paint vats.

Indigo is a substantive dye, which means that you do not have to pre-stain.

Indigo does not dissolve in water. In order to be able to paint with it, the oxygen will have to be removed from it, also known as 'reduction'.
You do this by making the dye bath basic with calcium hydroxide and reducing it with fructose. The indigo then dissolves and can adhere to the fibers.

Dyeing with Indigo is magical. Due to the reduction, the blue color disappears as soon as your fibers are in the dye bath. When you take them out and oxygen is added, the oxidation process begins. Before your eyes you see the color slowly change from green to beautiful shades of blue.

Facts
Indigo…
… is sometimes seen as the 'King' among dyes.

This is one of the natural dye products described in the book Eco-dye by Anja Schrik.
(To prevent leaks, we pack powder substances in plastic).

Recipe

Basic recipe for 100 grams of wool, silk or cotton to dye blue

Necessities:

- 25 grams of indigo
- 50 grams of calcium hydroxide
- 75 grams of fructose
- 5 marbles
– electric stove or stove
- an old (cast-iron) pan and strainer
– apron, gloves
– (glass) jars, buckets or trays
– 1 cup vinegar
– 2 cups of household soda (if you are going to dye cotton)

NB: Indigo is a substantive dye, meaning you don't need to stain.

Step 1: Wash (only if you are going to dye cotton, skip step 1 if you are going to dye wool or silk)
Fill a bucket with plenty of water and 2 cups of household soda and leave your cotton in it for 24 hours. Rinse well the next day.

Step 2:
Dissolve the fructose in a bowl with 200 ml of warm water (+/- 90°).

Step 3:
Fill a easily lockable bucket or jar with 200 ml of warm water (+/- 90°). In this you put the indigo and marbles and make sure the lid is tightly closed. Now shake until all the indigo is well dissolved.

Step 4:
Dissolve the calcium hydroxide in a bowl with 200 ml of warm water and stir well.

Step 5:
Heat a pan with +/- 3 litres of water and bring to a temperature of about 50°.

Step 6:
First add the indigo solution and stir well. Then add the fructose solution and finally add the calcium hydroxide solution. You stir this in very carefully to avoid oxygen entering the vessel.

Step 7: Painting
Make sure the fibres you are going to paint are wet (squeeze out the excess water). Carefully lower your material into the pan, making sure it is well-spaced and submerged. (Again: make sure that as little oxygen as possible enters the vessel by stirring very carefully).

Step 8:
Take out your material after about 5 minutes, squeeze it well and let it oxidise to air.

Step 9:
You can repeat steps 7-8 several times to achieve the right colour for you. Then rinse and fix in a bucket of water with a cup of vinegar.

Step 10: Fix
Rinse the fibers and let it sit in a bucket of water with 1 cup of vinegar for an hour. Then rinse well and hang to dry.