Shelf Life of Procion MX Dye Concentrates
With dyeing, everyone has a different approach, different rules and different beliefs. I find that a lot of what people know about dyeing is not necessarily based on testing but on someone else's assumption that is passed on as fact. I have learned that just because it is written in a book that it doesn't necessarily mean that it's scientific fact.
That leads me to doing a lot of testing on my own. Because I rely so much on dye recipes it's important to know how long my dye concentrates last. I know that I have had problems when I make a recipe with an old dye.
In 2011 I set out to test this for myself. I made up a complete set of my dye concentrates. I only use 11 dyes (10 primaries and 1 black). Each week I used those original dye concentrates to dye a set of fat quarters in each color. That's 11 fat quarters every week until the color became noticeably weaker. I dyed the color one week beyond the date it weakened just to make sure I didn't have some sort of anomaly going on.
I kept the dye in the refrigerator between dye sessions and I made sure that my batching temperature and batching time (3 hours) was consistent each time.
That leads me to doing a lot of testing on my own. Because I rely so much on dye recipes it's important to know how long my dye concentrates last. I know that I have had problems when I make a recipe with an old dye.
In 2011 I set out to test this for myself. I made up a complete set of my dye concentrates. I only use 11 dyes (10 primaries and 1 black). Each week I used those original dye concentrates to dye a set of fat quarters in each color. That's 11 fat quarters every week until the color became noticeably weaker. I dyed the color one week beyond the date it weakened just to make sure I didn't have some sort of anomaly going on.
I kept the dye in the refrigerator between dye sessions and I made sure that my batching temperature and batching time (3 hours) was consistent each time.
The top row of fabrics is the control group and the bottom row are the fabrics when they first showed they were weakening. I know it's difficult to see the different with the cobalt, orange, black and deep yellow but trust me, there is a difference!
The colors are the Dharma Trading names. The results are listed below (left to right in the photo). The dye showed the changes the week AFTER this date.
Fuchsia - 56 days - 8 weeks (means 8 weeks of good results and the dyed showed weakness at 9 weeks)
Cobalt - 63 days - 9 weeks
Sky Blue - 35 days - 5 weeks
Deep Orange - 63 days - 9 weeks
Grape - 63 days - 9 weeks
Turquoise - 35 days - 5 weeks
Deep Yellow - 63 days - 9 weeks
Cerulean - 49 days - 7 weeks
Lemon Yellow - 56 days - 8 weeks
Light Red - 56 days - 8 weeks
I did not continue the test to determine when the dye totally fails. I was only interested in when the dye becomes weaker because that's when I have to stop using a concentrate for my recipes. I can still use the dye for other projects (tie dye, quilt backs, clothing, fun fabrics), just not for things like my fabric palettes and gradients that rely on specific recipes. The other reason I do not need to know when a dye will ultimately expire is because I rarely have a bottle of concentrate last longer than 2 months. I go through a lot of dye!
Now I can put some expiration dates on my dye concentrates. Once a dye concentrate passes it's expiration date I will use that dye only for non-recipe based dyeing.
These results may or may not work for you. I encourage every dyer to test their dye concentrates. So many factors contribute to this that I don't think any of us can rely on one set of guidelines for everyone.
The colors are the Dharma Trading names. The results are listed below (left to right in the photo). The dye showed the changes the week AFTER this date.
Fuchsia - 56 days - 8 weeks (means 8 weeks of good results and the dyed showed weakness at 9 weeks)
Cobalt - 63 days - 9 weeks
Sky Blue - 35 days - 5 weeks
Deep Orange - 63 days - 9 weeks
Grape - 63 days - 9 weeks
Turquoise - 35 days - 5 weeks
Deep Yellow - 63 days - 9 weeks
Cerulean - 49 days - 7 weeks
Lemon Yellow - 56 days - 8 weeks
Light Red - 56 days - 8 weeks
I did not continue the test to determine when the dye totally fails. I was only interested in when the dye becomes weaker because that's when I have to stop using a concentrate for my recipes. I can still use the dye for other projects (tie dye, quilt backs, clothing, fun fabrics), just not for things like my fabric palettes and gradients that rely on specific recipes. The other reason I do not need to know when a dye will ultimately expire is because I rarely have a bottle of concentrate last longer than 2 months. I go through a lot of dye!
Now I can put some expiration dates on my dye concentrates. Once a dye concentrate passes it's expiration date I will use that dye only for non-recipe based dyeing.
These results may or may not work for you. I encourage every dyer to test their dye concentrates. So many factors contribute to this that I don't think any of us can rely on one set of guidelines for everyone.