How we choose UV Varnish?
UV Varnish is the coating which can be coated on the printed matter to appear its gloss, friction and waterproof.
Therefore, how we judge the quality of UV Varnish?
1.Observing UV Varnish color. Put UV Varnish on the transparent gloss vessel, the lighter the color, the better.
2.Smell. UV Varnish contains 95% solid content, the volatile is small.
Therefore, good UV Varnish smells not smell, especially after curing.
3.The surface of UV varnish will not be solidified as edible oil after kept a period of time.
Put a few UV Varnish on the sheet glass, if UV Varnish will not be solidified after 24h, it is the true UV Varnish.
4.Viscosity. You can use different viscosity according to different machine, like the coater or printing coating machine.
5.Leveling. The leveling is not good if there is a ripple after cured.
6.Skin irritation. Using a few UV Varnish on the back of a hand and observing it around 20 minutes.
Good UV Varnish does not irritate the skin, normal and cheap will be caused the
erythema and bad UV Varnish will cause the blisters on the skin.
7.Measured solvent content. Putting UV Varnish on the graduated vessel (diameter of less than 50mm)
left of about 12h and observe how much volatile. If UV Varnish significate reduction,
indicating too much solvent is added over UV Varnish. That is inferior product.