mottling or snowflakes issues on board offset paper

if someone can tell me to correct this issue without change type of paper as solution?
I use UV inks and varnish. Tks

 

Maybe you have problem with emulsification.The ink chemistry is critically important. Temperature also plays a role, as a very hot day lowers the viscosity of the ink and pulls water in more easily. Too much water creates snowflaking, leaving voids and unclear images on the substrate.

 

Tks, I print on polyboard paper with EB (electronic beams) inks, the pressroom have AC, water//ink balance generally control, agree with you about causes of snowflakes but I suspect type of blankets used or packing squeeze between plate cylinder on Komori/Chambon press.

 

Ok check the blankets but also i have read it that calcium compounds in paper may also leach out, build up and overwhelm the printing process under certain press conditions, causing either plate scumming or plate blinding with blanket and roller glaze impeding the transfer of ink and necessitating frequent but ineffective press wash-ups.”