The Fast and the Fugitive
It’s time to play…
It’s all fun and games until your colours fade away. When we talk about dyes, we often refer to them in one of two ways: substantive or adjective. A substantive dye is one that does not need a mordant to adhere to the fiber. It is capable of bonding directly to the fiber on its own. An adjective dye does not bond to the fiber on its own and requires a mordant to help the dye adhere in a lasting manner. We also use a few other terms when talking about dyes—like fast and fugitive. A dye that is fast means that it has staying power. A dye that is fugitive means that it’s going to run for the hills–ie, is going to fade in some manner and make you weep tears of woe for all your hard work wasted. This fading can happen by washing, wearing, or being exposed to light—the latter being one of the more common ways for a dye to fade. From what I’ve read, there are very few substantive natural dyes. The majority require you to add a mordant to your dyeing process to help not only bond the dye to the wool, but also to help a fugitive dye become more wash- or lightfast. It is recommended that one perform a lightfastness test on naturally dyed yarn to determine whether or not you’ve achieved a relatively stable dye. This is also recommended to test for fastness anytime you experiment with a new process or dyestuff. It lets you see firsthand if it worked.
Following are the results from the lightfastness test I conducted on the dyes used for Dye Day #1. It is very important to note: This is the unmordanted yarn that I used as a control. I repeat, this yarn is unmordanted! I wanted to see how fast these dyes were on their own. To my knowledge, with a mordant such as alum, these dyes are all quite lightfast. The lightfastness test was conducted for exactly 1 month, from June 23 to July 23. Swatches of each yarn were collected, and half was tucked between several sheets of dark construction paper, while the other half was left exposed to full sunlight outside. Here goes:
As you can see, the majority of the swatches demonstrate a study in lightfastness FAIL. A few, like the elm and onion, only faded a little bit. The alkanet faded more than I expected, but given how super unexpectedly dark it dyed to begin with, it’s really faded to closer to the colour I thought it was going to dye anyway. Particularly low scores go to safflower and eucalyptus. They surprised me. And the TOTAL FAIL! of the lightfastness test goes to… annatto seed. Whoa, nelly! For something that was so willing to dye everything in sight, it sure did fade fast. The annatto was gone by week 2. Some of these dyes, like the eucalyptus, are said to be substantive, and I think that perhaps under normal circumstances it would not have faded so much. We’ve had crazy high UV days here this summer, such that it would test the lightfastness of dirt, I think. I suspect that if this test were conducted at a different time of year, the onion, alkanet, elm, and eucalyptus would have faired much better. Just conjecture, but I think a safe assessment. As always, I’d love to hear about your results with natural dyeing.
Live happy, dye happy!