How to Make Lake Pigments

What are lake pigments? I am fully aware that most of you might not find that to be the most riveting topic but, to me, they’re a very exciting thing.
I will try to explain what lake pigments are and how to make them in the briefest and least painful way that I can . They’re my new favourite thing and I am planning on frequently working with them for the foreseeable future.

  lake pigments are just like regular pigments however instead of the pigment being made my grinding down a material- lake pigments are made by precipitating a dye with a metallic salt.

 They’re precipitated (which means that they are being turned into a solid from a solution) with the use of a strong alkali. You can basically make all kinds of paint from anything with a colour using this method, and I think that’s pretty sweet.

 

Now let me break that down a little bit using red cabbage as an example. There are three components or ingredients that go into making a lake pigment. You need a dye, a metallic salt, and an alkali.

Let’s start with dyes. Dyes are technically aqueous solutions that contain colour which can then be applied to a material. This is the case in textile dyeing where the colour bonds onto a fabric using a mordant. Dyes can be extracted from materials either through aqueous extraction or solvent extraction.

That’s a science-y way of saying that you can either boil them or that you can leave them to stand in alcohol or another solvent. That’s how tinctures are made. Usually boiling is the way to go for me- its much safer and much faster.  

chopping the red cabbage

boiling the red cabbage

pouring the red cabbage dye through a sieve

Now for the metallic salt. The metallic salt that I’m using is alum a.k.a hydrated potassium aluminum sulfate. This is the most common, cheap, and easy to find. Alum is used as a mordant and fixative in textile dying amongst other things . I got mine from a local spice shop.Not all dyes will grab onto alum so it’ll be a matter of experimenting. Other than alum you can also use Barium Sulfate, Calcium Sulfate, Aluminum Hydroxide, and Aluminum Oxide.

The alkali that using is Washing soda (sodium carbonate). You can also use potash but washing soda was the easiest to get because I made it from baking powder

I should mention at this point that natural Lake pigments have a problem with being too fugitive (this means that light fades them) as this is a common characteristic of dyes that come from organic sources such as plants. This is something that ill be exploring further the next few months and we’ll see how big of a problem this really is and how we can be remedied. Now to turn this gorgeous red cabbage dye into a powder pigment.

I then grabbed two cups and poured some hot water into them. I dissolved some washing soda into one cup, and some alum in another cup. I stirred till both were dissolved then I added the alum solution to my dye followed by the washing soda.

The dye fizzes and this is usually when you would notice colour change. Since red cabbage is a natural PH indicator, it turned blue as it became basic.

Before and after Alum + Washing Soda

I let it settle for a few hours and then i grabbed a coffee filter and funnel and poured the solution into it. This will filter out the pigment which will then be dried and ground.

After a few hours the solution was done being filtered and I ended up with a thick blue paste.

I open up the filter, spread it on a plaster bat and level it out so it could dry faster.

It’s actually a really pretty shade of blue- which is very difficult to make from organic materials. When making lake pigments there are lots of pleasant surprises.

After 3 days the paste was dry and had turned into hard dry pieces. I notice that the colour had turned more towards the green side than the blue side.

I peeled off the pieces into a coffee grinder, ground them, sifted the powder, and ended up with a pile of red cabbage lake pigment. Success!

red cabbage pigment

There’s a few things that you can now do with this pigment. You can mix it with gum arabic, honey and glycerin to make oil paints. Egg yolk to make tempera. Gum tragacanth , water, and chalk to make soft pastels. Or you can do what I like to do and that is to make oil paint by mulling it with an oil or alkyd.

Materials Used:

US

Washing Soda: http://amzn.to/2wSFUzs 

Alum: http://amzn.to/2jfRlMX

 UK

Washing Soda: http://amzn.to/2eWsQCY

Alum: http://amzn.to/2xeuVRl

Using Format