• Both inline OP varnish and outline OP varnish are available.
• To avoid any curling or surface distortion, be sure to use a varnish which has been specifically formulated for use with YUPO.
• Depending on the type of varnish, some yellowing may occur over time. Please consult with your ink manufacturer.
• OP varnish for general paper can also be used with SUPERYUPO (FRB [G]). In this case, please consider the solvent absorption capacity of SUPERYUPO.
• Select a varnish brand according to the application and required performance.

• The application of a coat of varnish is the most effective way to protect the ink surface and improve gloss.
• To prevent distortion due to heat, including deformation and curling, be sure to use a low-heat type UV lamp (water-cooled or infrared-reduction type). When dealing with the high-volume lighting necessary for dark color patterns, even water-cooled systems may produce high temperatures, which may result in distortion of YUPO. As a guide, avoid stacking sheets of YUPO in temperature conditions exceeding 50℃.
• In the case of oil-based offset printing (oxidative polymerization-type inks), coatings should be applied off line. So as not to detract from the glossiness of the finished coating, limit the use of spray powder during printing as much as possible, or remove the powder from the printing surface prior to application of the UV varnish coating.

• After the application of the varnish, use a drier with a long delivery and maximize air speed and pressure to ensure adequate drying.
• Additionally, make any necessary adjustments to ensure that sheets of YUPO is delivered at a temperature not exceeding 35℃. This will prevent blocking of the varnish.
• In addition to safeguarding the print surface, this type of varnish coating is also effective in reducing both the use of spray powder and any blocking trouble with the pile.
• When selecting the varnish, consult with the manufacturer, and confirm it by testing in advance. Water-based varnish gives a gloss effect with SUPERYUPO (FRB), which features high surface smoothness, and ULTRAYUPO (FEB [G]/FEBA).

This method is not suitable for use with YUPO.