Using Turmeric as a paint pigment

[Dave]

I've got two pots of white eco-paint that I was thinking of mixing with turmeric as a pigment. Has anyone done this? How do you do it, shall I just simply pour in some powder into the paint?

[Clara]

A friend of mine uses turmeric as a pigment in wood finish and yeah she just adds it in and stirs it.

[Shirley]

Ooh I fancy giving that a go - I've got 3 pots of errm non eco paint that we've had for ages but the yellow is a bit pukey - I bet a bit of turmeric would make it much nicer.

[Annpan]

I haven't done it but I did try with beetroot and it wasn't a nice colour. I would suggest mixing yourself up a tester pot first to check the colour.

Take a 1/4cup full of paint and stir in a tiny amount of turmeric, adding more dependent on the colour you want but you want to start off small. Make sure it is really well mixed before painting it on to anything.

After you have painted a small area leave it to dry for at least 2 days before deciding you like the colour - my beetroot paint looked lovely until day 2 and by day 3 it was a dirty brown (like nicotine stains)

If you do like it you will have to use a big clean bucket and mix all of the paint at the same time.... otherwise you will end up with 2 different shades no matter how careful you are.

You say eco-paint, beware that there may be 'brighteners' in it usually a kind of blue tinge that might mix with you pigment and make a funny colour that you weren't expecting. I used Lime paint, and it is typically easy to colour.... beetroot is obviously not the right thing to use... I quite fancy trying paprika at some point... and maybe heather or lavender...hmmmmm

HTH

[Green Aura]

On that wonderful Grand Designs - you know the one Ben Law built - he painted his walls with turmeric and chilli dyed paint. I can't remember what his paint base was but the colours were gorgeous.

[The Riff-Raff Element]

You would possibly get more intense, longer lasting colour by extracting the pigment using a solvent other than water, then driving off the solvent, grinding down the "pure" pigment in a pestle and motar and adding that to a nuetral paint base - Dulux make these for the in-store paint mixing systems, but eco paints would do the job I'm sure.

The extraction is best done with a device called a Soxlhet extractor which can often be found on ebay and in junk shops, particularly since practically no-one does proper lab prep chemistry any more, but a kilner jar with a fresh seal to allow viorous shaking will do. The seal will perish eventually, so keep an eye on it.

Turpentine (the real stuff) is good for this. Basically, you put a few tablespoons in the jar, seal it, give it a bloody good shake, open the catch (away from you!) to let the pressure go, then leave it for a few hours before shaking again. Keep this up for about five days, then strain through a coffee filter cone into a basin and leave it somewhere dry but outside to evapourate, scrape off the pigment and away you go.

Paint made like this can last for decades before fading.

Beware - the solvent is flamable and so really this sort of thing should be done outside and without a fag on.

[Ellendra]

Beware - the solvent is flamable and so really this sort of thing should be done outside and without a fag on.

I keep having to remind myself that "fag", in Europe, is not a bad word.

The Mayans used to make a blue paint by gently simmering the pigment with clay for 3-5 days, probably adding water as they went to keep it liquid. A chemist studied this technique and found that it caused the clay particles to open up enough for a pigment molecule to become trapped inside. This paint is still vibrant centuries later.

Don't know if that helps any, but I thought it was cool.

[The Riff-Raff Element]

Beware - the solvent is flamable and so really this sort of thing should be done outside and without a fag on.

I keep having to remind myself that "fag", in Europe, is not a bad word.

The Mayans used to make a blue paint by gently simmering the pigment with clay for 3-5 days, probably adding water as they went to keep it liquid. A chemist studied this technique and found that it caused the clay particles to open up enough for a pigment molecule to become trapped inside. This paint is still vibrant centuries later.

Don't know if that helps any, but I thought it was cool.

Though they might not have called it this, what the Mayans were doing is called "mordanting." The mordant - alum or zeolites these days - does exactly you say: it grabs on to both the dye molecules and the fabric and holds them fast. The word "mordant" comes from the latin meaning "to bite."

I think it's cool too. Some much in nature is, isn"t it?

[invisiblepiper]

Not being funny - but make sure your turmeric is clean - I know someone who used turmeric will oils for picture painting - rather than walls - and it grew a rather disgusting hairy mould!

[Dave]

Thanks everyone! So as I can gather there are three methods

Number one - Throw the turmeric in with the paint and mix, draw backs are it will fade quite quickly but it is VERY simple to do!

Number two - Extract the pigment from the turmeric

Turpentine (the real stuff) is good for this. Basically, you put a few tablespoons in the jar, seal it, give it a bloody good shake, open the catch (away from you!) to let the pressure go, then leave it for a few hours before shaking again. Keep this up for about five days, then strain through a coffee filter cone into a basin and leave it somewhere dry but outside to evaporate, scrape off the pigment and away you go.

Riff Raff Element - So just add turpentine to the turmeric and give a good shake? Any idea of the quantities of either? It seems like a lot of work and as you have to let the pressure go constantly I'm assuming it explodes if you don't? Do you seal it between shakes?

Is there a simpler way of doing this? One that takes a day rather than five?

And finally

Number three -

Use a mordant to 'fix' the turmeric dye. I thought this was for fabric only? Would it also work for paint? Would salt be okay to use as a mordant if you can use it for paint???

[The Riff-Raff Element]

Dave - For the quantities I'd suggest about 10 table spoons of turmeric to 500ml of turpentine. The jar won't explode, but it is best to let off the pressure after shaking because that way it is controlled and no-one gets a nasty surprise if they open it without thinking later on.

There are quicker ways; I suggest turps because it is a natural product, but ethanol (surgical spirit) or acetone (nail polish remover, but the uncoloured variety) will work far quicker and will also evapourate more quickly afterward. Of the two, I'd say ethanol is both safer to use and is not particularly damaging to the enviroment. Acetone is a bit nasty, but both are (usually) produced from oil or natual gas.

You shouldn't ordinarily need a mordant in paint, but curcumin - the pigment - is water soluble (you can't use water as a solvent for the pigment, unfortuately, as curcumin is not long stable in water) so the finish probably won't be washable, though how much comes out will depend on the formulation of the base paint.

It is more trouble than just dropping turmeric in the tin, but at least the paintwork won't go mouldy.

I've made some paints with the girls (trying to demontrate that chemistry can be fun! ) by extracting pigments like this, then mixing into linseed or hemp oils (with a bit of ground chalk to thicken them if needed, turps to thin) and they've worked rather well as art materials.

Never tried to paint an entire wall with them though.

[snapdragon]

If you're adding it to water based paint surely it won't mix with the turps?

I've used Turmeric to dye wool with no mordant, maybe if you cook the powder in water first it will be more stable?

[Annpan]

Riff-raff said to evapourate all the turps so I guess it would mix then.

Would white spirit work? I have loads of it (left by previous occupiers) sitting in the shed.

[The Riff-Raff Element]

Riff-raff said to evapourate all the turps so I guess it would mix then.

Would white spirit work? I have loads of it (left by previous occupiers) sitting in the shed.

You do indeed need to drive of the solvent. You should end up with a yellow / orange sold (curcumin) though you might get an oily liquid if it isn't too pure, but it will go into the paint as it doesn't actually need to disolve in that.

White spirit will disolve curcumin pigment to an extent, but it is not a great solvent for that type of chemical compound I'm afraid. But if you've got lots of it, just use lots of solvent to a small amount of turmeric. I confess I avoid white spirit 'cos I fret about how poluting the vapour is, but in practice the amounts involved are actually pretty small compared to other sources.

[jampot]

... I quite fancy trying paprika at some point... and maybe heather or lavender...hmmmmm

HTH

ooh paprika that would be lovely! ill remember that for when (if i ever get to it) i do the bedroom