Thursday, 21 May 2009

Cellulose Mordanting

When I first started on my path as a natural dyer I wanted to work with silk. I was particularly interested in making embroidery silks that I could use for 17th century reenactment. Very soon after starting I came across references to using linen as the ground for the embroidery and wondered if I could dye the linen base.

The learning experience is unusual with natural dyes, you start off thinking "oh this is easy" then you progress to the " I know that already" stage, and then you begin to realize that the subject is so huge that you can only scratch the surface in a lifetime. I have been at that stage for quite a while, but I do feel that having concentrated on dyeing silk and linen I am pretty competent at getting a good colour on those particular fibres. I would never describe myself as an expert - ever- after all "an ex is a has been and a spurt is a drip under pressure" and who would want to be described thus? But I digress as usual.

The point behind this post is that I have been doing some experimenting with cellulose mordants, the results I have obtained so far (and I do accept that it is a very simplistic start) have made me realize that I need to do some serious study here and ultimately write an academic paper on it, so please excuse me, but I am going to put a copyright on this post, in preparation for that final paper!

Coming from an historical perspective I have always used the alum tannin mordant method for linen (and cotton). I use oak galls as my tannin source, rather than tannic acid, to appease the environmentalist in me, I may have to adjust proportions accordingly, but I follow given recipes. My first reference when I started on cellulose was Gill Dalby's book natural dyes for vegetable fibres. She was an amazing lady who did much to promote natural dyes - and worked with the environment in mind, it is from her book I get the 8% alum and 7% cream of tartar recipe for protein fibres. Jim Liles The art and craft of natural dyeing was my next book and I learned about using aluminium acetate as a mordant from him. (both are well stained as you can imagine!) When I started using the Earthues extracts I thought I'd try out the commercially produced aluminium acetate as Michelle Whipplinger is so pro using it, it's certainly quick and easy and is very good if you have a mixed fibre combination like hemp silk.

In my own sweet little world though I wasn't so sure, so I decided to do a simple experiment. I broke a 100g hank of cotton (my wonderful new organic cotton boucle, which will be available very soon!!!) into smaller hanks of even size. Wetted them out for a couple of days first and then scoured them with washing soda and detergent keeping them all together. I then put 2 into an aluminium acetate mordant and 2 went through the alum and tannin method of mordanting. After rinsing them well I dyed 1 of each in madder and 1 of each in cochineal extract. The only thing that was different about the preparation was the actual mordant. Now look at the results! The alum tannin has taken the dye much more intensely for both dyes. I have not cheated here, it was a straightforward simple experiment.

Based on what I've seen so far, I think I will continue to use the older method for now - but as I get more into the research I'll keep you informed - and in the mean time I'll continue to stock aluminium acetate powder in my shop!!!
© Debbie Bamford, May 2009


Willington Weaver said...

Hi Deb

I'm so glad you've done that experiment! I've always used wool, as that is my passion, a sustainable British fibre!

But was asked by a friend to help her dye some cotton in natural dye extracts for a quilt she wanted to make. I could have used Aluminium Acetate as it would have been quick, but she wanted to use the "traditional" methods, so we opted for alum, tannin (using Oak Gall extract), alum. The colours we got were wonderful, so rich and luscious! See the results here:
I've been flirting with the idea of using Aluminium Acetate, but now you've shown me your results, I think I'll stick to the long, but richer way!

The only downside to this method is the amount of water that is used, and in a domestic environment, there is little I can do about that!

Many thanks for your valuable experiment.

Best wishes


Debbie said...

Gorgeous colours Alison, really love the purple - very Mulberry Dyer!!!
It's definitely worth taking the trouble!

Nina said...

How do you prep or process your oak galls for tannins? I have some here that I'd like to use for some linen dyeing experiments in a couple of weeks.

Debbie said...

Hi Nina,
I now buy my oak galls already ground and in large quantities, however if you have an old coffee grinder that you don't want to use again, then that works well. Otherwise its heavy duty grinding in a pestle and mortar - I've used both these methods on many occasions, the pestle and mortar particularly in a living history situation
Hope that helps and thanks for reading

Benita said...

I am getting ready to start my summer dyeing, and, like you, I use only natural dyes. I love the colors and how well they blend with one another.

I'm going to be giving a talk on natural dyes in September to an embroiderer's guild and you've given me the idea to dye some silk to show them.

I love your blog, and have bookmarked it. I can't wait to read more about your experiments.

Margreet said...

Hi Deb,
Thanks for sharing this with us all! What a big difference the mordanting makes. Lovely strong colours with the long mordanting process.
I hope to get on with my red dyeing next month and will show you my results when ready.
greetings Margreet

jane d said...


I use al acetate and I wonder if the oak galls give a richer colour because they actually put a colour into the cloth/yarn whilst mordanting?

I've used the oak as a dyestuff in it's own right - might it be that the take up is not so much the answer as the same sort of richness one gets on dyeing a grey yarn - on e of my absolute favourite things to do!