Picric Acid

[np01]

Have been contemplating buying some Picric Acid and having a go at doing some dyeing. This is caused by the fact that any material with "picric" in its title seems to command bloody ridiculous prices. Whilst I'm not a PhD chemist, I have a distant background in science and I'm fairly comfortable with the protocols for handling and storage of Picric Acid.

I was wondering if anyone had any experience of using it as a dye, in particular what's the recommended concentration of the acid, and how long should the materials be submerged in the dye?

Thanks

Nick

[harelug]

I tried to track down an old thread on this subject but it appears to have been deleted. I've used the stuff for years and the jist of the thread was that i had to be off my head to even contemplete using it. I've still got some of the conc stuff, as strong as it gets without crystalising. I've also a bottle of more dilute stuff, can't remember the dilution, maybe 1:10. I usually dye a few feathers or scraps of fur rather than whole capes at a time and just check on the progress of dye uptake. I sem to remember 5-10 mins is about ok. It keeps for years, and is reusable so you won't need much.
I'd be interested to hear where it can be easily purchased these days.

[Wildfisher]

this one?

http://www.wildfisher.co.uk/smf/index.php?topic=4467.0

[Scotaidh]

I'm a chemist and I work in a lab, I don't think we've got any on the shelf (if we do I'll be doing some after hours dying!) but it is cheap and available freely from chemical suppliers.

Give me a shout if you need a hand.

[np01]

Believe it or not it's available from a biochemical supplier on ebay! ?14.99 per litre plus about another ?5 P&P

[harelug]

Picric acid in it's dry crystalline form is highly explosive, hence the critisism on a previous thread on me using it. (Not the link you gave Fred.)
My original source was a 1/2 kg jar of crystals topped up with water. When we used it we drained off some of the saturated solution, topped the jar up with fresh water, gave it a shake, soaked the large cork stopper and wrapped the lot in clingfilm. These days it's usually supplied ready diluted for the required application, which I think was measuring cholesterol  content of gallstones. Long time ago and my memory isn't quite what it was.