Gloss UV coating or varnish an be applied to the whole page, or just to certain areas – a process referred to as Spot UV. In either process, UV coated elements darken the color of the print, so take this into consideration with your designs. With pantone color guides you can also use Coated references vs Uncoated to see the difference a coating can make.
Spot UV coating draws attention to that part of the design by making it pop out visually in only certain elements or are a design element all their own. UV Gloss varnish utilizes UV light to cure it during the printing process. This varnish is clear, and will dry with a gloss appearance. This option can be applied to many different stocks and is quite popular to add that extra design aspect. It adds shine, and protects the printed surface underneath from moisture and other types of damage. The only negative is that gloss UV does show fingerprints but mainly only noticeable in large coverage.
In the above design you can see the designer used Spot UV as a background as well as the logo. No artwork was behind these elements, just the spot UV to make the wow factor.
In this next example, spot UV is placed directly over the logo to make it pop while the rest of the design is the matte appearance.