Spot UV varnishes are common used UV surface varnishes. It is cured or hardened by UV light during the printing process. Films are commonly used to match the UV position perfectly.
When making paper boxes and bags, UV varnishes are often used for logo as a spot application where only specific parts of the box and bag surface get a UV varnish. For flexibly used UV spots, it can also give effectively texture to different areas on boxes and bags, and leave other area untreated.