If you can get fresh ginger it is an excellent tannin and does not have any colour.
On the other hand, coffee is one of the best sources of other bioactive compounds, such as flavonoids and phenolic acids.Apr
Anthocyanidins are particularly high in blackberries, blueberries, cranberries, cherries, and elderberries. All contain >80 mg/100 g. Elderberries are the highest at 749 mg/100g. Cyanidin is the predominant or only anthocyanidin in most fruits.
1 – Gallic tannins.
(hydrolyzable tannins)
Clear tannins that do not add much colour to the fabric such as
- tara,
- oak galls,
- oak bark
- oak nuts
- sumac (leaves and galls).
- blackberry leaf
2 – Ellagic tannins.
(Gallic tannins in combination with Ellagic acid)
Tannins with a lot of Ellagic acid, sometimes in combination with flavonoids that will add a yellow colour to the fabric such as
- myrobalan,
- pomegranate
- henna
- walnut hulls
- pecan hulls
- chestnut bark.
Catechic tannins.
Condensed tannins that will add brown and reddish hues to the fabric such as
- black tea,
- cutch,
- quebracho
- Acacia mearnsis extract (mimosa tannin)
- persimmon
- ceriops tagal
Tannin affinity
Tannins love proteins so they bind easily with silk and wool. They also love amino-acids and alkaloids which makes them a great pairing for cotton. Heating brings out the colour more, if the material has any.
Example: pomegranate rind soaked cold will give a soft buttery shade, but if I heat it it will become a vibrant yellow. Of course you can play around with these variables.
In percentages of WOF it is important to know the % of tannin in your raw materials. Oak gall tannin from the shop has around 70% gallotannins, sumac leaves have around 30%. That means that you may have to adjust recipes if you are swapping the raw materials
Reaction of tannins with ferrous sulfate
Tannins react to mineral salts, the most known and obvious being ferrous tannin.
Tannin in combination with ferrous sulfate form a strong insoluble bond called ferrous-tannate. They are shades of grays and black depending on the percentages.
Different tannins may give different shades: the gallotannins have a slightly purplish hue, where the yellows of the Ellagic tannins sometimes give a green tinge.
ferrous sulfate + tannins in leaves
Armed with this knowledge we now understand how tannin rich leaves will always give us dark results on ferrous sulfate mordanted fabric.
We can manipulate this by two ways!
1 – By soaking leaves in water for three to seven days, the hydrosoluble tannins will release in the water, leaving less tannins in the water. This way we create more subtle results.
2 – By using micro doses of ferrous sulfate we will have less intense blacks.
If you are going to use fresh, tannin rich leaves, you may want to lower your ferrous sulphate mordant to 0.5 percent. But in that same reasoning you would up the number to 1.5 or even 2 percent if you are using leaves that are weak in tannin.
or use leaves fresh, not soak
- Add 2 heaped spoons of soda ash, this will bring out the colours more (these tannins love alkaline environments) and will act as an antioxidant. Stir well.
- Your batch is now ready for use with pre-wetted textiles
What makes a great blanket
Any natural fabric can make a good blanket, but since we are using it multiple times and it’s not for display, going for something cheap(ash) is a great idea.
Soft material with a bit of stretch is great. I LOVE French Terry, with a soft side and a smooth side. Flannel is super as well. I also have great experiences with jersey materials.
A lot of texture in your blanket will result in the texture being visible in your background, which may or may not be what you are aiming for.
Pro Tip:
After bundling, before heating, roll your bundle on a hard surface, while pushing, for a minute or two. This will make sure the layers get full contact, and your result will be a more even background
What to do with your tannin blankets and leftover tannin baths.
Your left over blankets can be reused immediately without rinsing, simply soak again in your leftover tannin bath, will give you enough tannin to do another round. If you want to wait another week before using your blanket material, I recommend doing a short laundry circle, drying and storing marked with a label.
Tannin baths keep well out of the fridge for about a week. If you want to store your bath beyond that I recommend storing in the fridge in a well marked bottle or box. But personally I would just pour out and make a new bath. Mold is a real thing and it is very unhealthy
https://www.tannins.org/tannin-in-nature/
https://youtu.be/xMmU3iC1X5M?si=KZYOwn6dtM82UEIi
rust print
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