I would like to ask why on UV-varnishes and inks (radical and cationic curable), the adhesives have poor adhesion?
I tried to raise the polarity of the UV-varnishes by adding acrylic acid, but the adhesion of adhesives does not improve.
Even on pure UV varnish, contains only Trimethylolpropane trimethacrylate + photoinitiator, the adhesion of adhesives is again poor.
Thank you in advance!