A common theme of frustration since I’ve started dyeing has been how difficult it can be to get good, informative resources on the hows and whys of certain dyeing techniques. For most other techniques, I have a series of ‘go to’ reference books which I can consult to at least have some idea of what I’m doing but I’ve yet to find something similar for dyeing. Fellow dyers, what is your favourite literature on the subject?
I’d seen in a few places that Procion MX dyes could in fact to be used to dye wools, as well as cellulous fibres and silk. The only thing you needed to change to use Procion MX dyes with wool is that, instead of using an alkaline dye bath with soda ash, you needed something acidic instead.
There was some ambiguity in the sources I’d read as to whether the wool could be left in the dye to react just at room temperature or required steaming, so I thought I’d give up reading and just see what results I’d get for myself.
The wool in question is 100% Bluefaced Lester (BFL), a lovely wool with relatively long staple fibres. It’s got a bit more lustre than things like merino and is particularly nice when blended with silk. I’d dyed a batch of this top before, so I already knew it was relatively clean so didn’t bother with any more intensive cleaning than just rinsing it a bit in cold water.
I soaked the fibre in an acidic mixture of water and citric acid. If you are a good person, looking for completely repeatable results from your dyeing, you would carefully measure the water to citric acid ratio to work out your pH but as I am not (and citric acid isn’t a strong acid either) I just bunged a load of citric acid in and left it to stand for a few hours.
When I was ready to get dyeing, I made up my Procion MX dyes to about 5 % concentration with hot water and squeezed the worst of the water out of the top. I really need to learn to be more careful when handling wet top as the weight of it meant it managed to pull itself apart in a few places. It’s really quite unsurprising that sheep are so talented at drowning themselves with the volume of water that wool can hold.
Then, I just flung the dyes on in the usual fashion. I don’t normally add any acid/alkaline directly to the Procion MX dye stocks, instead I rely on the pre-soaking to give me the pH I need. I try to dye with the top as dry as possible as too much water in the top means you’re essentially diluting your dye solutions and can end up with paler colours than expected.
When that was done, I wrapped the top up in cling film, steamed it for an hour and waited with a great deal of impatience for it to cool down so I could rinse it. I am paranoid about touching freshly steamed wools. Although wool is generally a lot harder to felt than people give it credit for, I’d rather not take any chances.
As I was curious to see whether the steaming was necessary, I took a small sample of the top but didn’t steam it with the rest. This sample is one I left for 12 hours without heating and one that I steamed for an hour. As you can see, while the un-steamed sample has retained some of the dye on rising, the majority of it has not fixed properly and just been washed off.
I assume the chemical reaction that fixes the Procion dyes to the fibre is better catalysed by alkalis than acids, hence the need for steaming to speed up the fixing reaction when using an acid dye bath. I’m going to have to do a little reading to see if that speculation is actually correct or not.
With the top rinsed and dried, I was really surprised to see how intense many of the colours had come out. I’m always a bit nervous working with reds and browns as it’s far too easy to cross the line from ‘rich autumnal’ to ‘bloody sludge’.
For comparison, the hideous red intestine looking wool is some BFL one I dyed using acid dyes. It’s not a true like-for-like in terms of the colour comparison but I’m not sure you’d be able to tell any difference in the dyeing process from looking at them. The fibre also seems completely unscathed by the dyeing process.
Overall, I’d say this worked absolutely as well as could be expected. The colours came out at the saturation levels and shades I anticipated, there’s no damaged to the fibre and the process is as quick and easy as using acid dyes. A good dyeing process is all about having control and in terms of that I have absolutely no complaints about unexpected, disappointing results here.
From this, I’d say there’s minimal difference between using Procion MX dyes to acid dyes on wool, at least at a superficial level. Just remember, if you’re using Procion dyes to steam the wool and make sure you use an acid, not an alkaline, dye bath. If you’ve had a go at doing this, I’d be really interested to hear about your results and experiences.