Hi,

From my previous instructable the heat sensitive phone case you may have noticed that i have been toying about with Thermochromic pigment and in this instructable I am going to show you this quick and easy way to make polymer clay that changes colour when heated up

Step 1: Stuff You'll Need

Polymer clay

I am using Fimo but i am sure Sculpy and other brands would work as well

Thermochromic pigment.
I'm using Green here. another thing to note is because we are mixing it with white fimo the end colour will be lighter but i will go into that more in the next step

Something to mix the two on

Self explanitory really

Step 2: What to Do

Step one

Warm up your polymer clay to may it pliable then form it into a bowl type shape

Step two

Inject some of the Thermochromic pigment into the bowl. the suggested ratio is 4 pigment to 1 but as we are working with a liquid and a solid i put a small amount in to begin with and added more as i went on. more on that in step 3.

As mentioned before because you are mixing it with white polymer clay you are going to get some colour change. as i am using white with green its lightened down. Take this into consideration when mixing your clay/pigment as you can get some nice colour changes, For example mixing red pigment with yellow clay will give you an orange clay that turns yellow under heat or blue pigment with red clay will give you a purple clay that turns red.

Step 3

Mix it together. This is the messy bit. i kneaded the pigment in adding more as it was absorbed into the clay and built it up from that way.

A few things worth noting:

1. The clay becomes stickier and more pliable the more pigment is added. it can make it a bit more difficult to work with.

2. As you mix the clay/pigment together the heat from your hands will cause the mixture to change colour skewing the colour you think it is. you may want to let it cool for a bit to see how deep the colour is before adding more pigment.

Step 3: Make Something!

And that's you!

Sculpt something. Bake it as per the products instructions and when you bring it out of the ovan and its colour has changed don't freak out, its supposed to do that remember

In the pictures you can see that i mixed up some green and orange but left some normal pink to help illustrate the contrast in colour change.

There is also a video of it in action.

A note to others wanting to try this:

I used liquid pigment as that is what i had to hand, I believe that the powder variety would produce a better result (I hope to get my hands on some soon) but if you get the chance to do so before i do please let me know how you get on in the comments below

Enjoy!