Hello,

I have observed bronzing of red pigments (quinacridones), when the pigment is at a very low level, and the processing temperature is high for the given pigment. I was told that under these conditions, the pigment becomes a dye and sublimation occurs, yielding the "bronzing" effect.

Can anybody confirm this?

Now, I have seen this in TPU parts colored with a PE carbon black masterbatch. Has anyone seen this before?

Thanks.