The base resin in all our polyester pigments is polyester resin itself so it should not cause any curing issues and as the grey pigment has cured that would lead me to believe maybe you have been sent the wrong pigment.

If you would like to ring one of our team or email us with your order number and details we will happily try and sort it out for you.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Hi, I have recently purchased some black polyester pigment from you and this appears to be causing me curing issues with my gel coat. My first application did not harden at all, and I assumed that I must have missed the MEKP addition in error! I had to remove with acetone, reapply release agent and retry, however I had exactly the same result. Again I removed with acetone and reapplied release agent.