QTR-Quadtone RIP

I just printed with QTR, 2200, UC on GoldFibreSilk and although the
print is pretty good (I'll reserve judgement until the morning when
it's dry), I did notice that when I angle the print to the light
source, it has a "solarized" appearance. I don't know if it's
characteristic of the paper, or ink, or curves. I don't quite know how
to explain it, and it would be impossible to post a jpeg showing it.
Do you know how I can correct this ?

Thank you,
Frank