Creative Commons images are CC BY-NC-SA 3.0


added to your
shopping cart

In stock 118 in stock
12.95 1+ units
11.66 10+ units
10.36 100+ units


Description: We've all seen toys and things that change color when you run them under warm water or heat them up in the sun. Some of us were especially mesmerized and had to find out what made them do that. It turns out that this is a property called "thermochromism" and it can be implemented in a number of ways. This particular pigment is a Leuco dye type pigment which is made up of a mixture of Leuco dyes, weak acids and salts microencapsulated in polymer. Sounds complicated, right? Nah, it's not so bad.

All you need to know is that this is a very fine, colored powder that changes to a clear powder when you heat it to about 92°F (33°C). This is really cool for a lot of reasons. You can mix this pigment with paint to create thermochromatic paint for craft projects or to make temperature indicators. It mixes with Sugru and Polymorph as well, rendering them both thermochromatic. Use a controllable electric heating source and you could even build a thermochromatic display!

This pigment comes in a 20g bag, which is more than enough to play with and just enough for a good sized project (depending on what you're doing with it). Careful not to overheat the pigment as temperatures over 200°C can cause irreversible damage to most Leuco dyes.


  • Red at Room Temperature
  • Turns Clear at Around 92°F (33°C)
  • Mix with paint, glue, resin, Polymorph, Sugru, etc.


Comments 10 comments

  • I’m hoping there are plans to use this on the Sparkfun coffee mugs.

  • this stuff i awesome!!!

  • Hi, loved the product and couldnĀ“t help to get it but … have a question, how is the process to follow in order to dye a garment properlly?

    thanx :)

    • It’s a weird, new material. Additionally, it’s a pigment, not a dye, and doesn’t exactly dissolve in water. You may be able to dye with it, but there’s no guarantee, and it will definitely take some experimentation. It looks like Dena Molnar and Nicole Tariverdian at MIT had some luck with this; check out their write-up here. Good luck! And if you learn anything new or get awesome results, share them here!

  • How much paint does 20g mix into?

    • This will depend on the paint you’re mixing it with, and how much of a color difference you want to see. Experimenting will give you the best answers for that :)

  • In the MSDS it says SOLUBILITY IN WATER Dispersible. Does that mean that you could make color changing liquid?

    • It means it disperses, not dissolves (think colloid).

      • So I guess color changing Mayonnaise then. :-)

        ETA: Scratch that, from the MDS

        INGESTION Induce vomiting immediately. See a physician. :-(

  • This reminds me of those Hypercolor shirts back in the 1990s, and those HotWheel cars that could change colors in warm water. Neat stuff!

Related Products