Today has happened a really strange thing: I used in fresch plastisol a black oxide pigment and I realised some really shining black soft baits with the first micro wave cooking, instead when I tried to cook again the rests of 1st cooking I obtained scorched plastic.
When I cook the left overs I use every time a shorter cooking process and it is usually easier for me to cook the remaining plastic. I tried again with same quantity of plastic and same quantity of black oxide pigment and again I obtained good baits with 1st run and scorched plastic with the 2nd one.
With same plastisol I made two other batches using fluorescent yellow pigment: no troubles during the 1st run, nor during the following ones, only good baits, of course the color changed during repetead runs.
Is there anyone that can explicate the reason why I scorched the black batches during the 2nd runs?