Drip-off varnish

also drip-off lacquer, twin-effect finish

The drip-off coating method is a two-stage inline finishing printing methods with which you can create impressive matt-gloss contrasts in the offset printing press. By combining different paints even better contrast than the spot coating can be achieved.

Technical background

In the first step the substrate is normally printed with an offset printing ink. In the last printing unit of the press, a special oil pressure Matt lacquer is applied partially. Due to the different ratios of the two surface tensions of each other after applied the paint work emulsion paint of the oil-pressure-paint-layer runs off and the matte effect is maintained at these locations. The remaining games to take the high-gloss aqueous coating. For this type of finishing a printing press with at least five printing units and a coating unit extra is the minimum requirement. In addition, useful also are hot air and IR drying unit.

Effect

It is possible to achieve excellent contrast between the different surfaces with up to 70% gloss differential. Unintentional gloss on Matt paint surfaces does not occur, in contrast to UV-varnishing. The paint is applied by a printing unit, whereby a good registration can be achieved. This, in return, to provide even the smallest details such as text, lines or grid with gloss contrasts allows.

Application possibilities

Substrates are particularly glossy coated papers. On this, the effect is to best advantage. Compared with UV coating layers, these layers are printed paint scratch-resistant. A stack temperature of 30 ° C, however, should not be exceeded. In addition, a good ventilation of the stack must be ensured. However, such information also hold the manufacturer ready.

Limitations

The limits in the choice of the paper and the time required to process machinery. It is also noted that oil-based varnish tends to yellow and a slight odor reserves, even after drying.

Costs

The process is in the mid price sector and provides customers in commercial printing an affordable entry into the inline finishing.

Sources and additional literature

[1] Beckmann, Till; Morlok, Franziska: Extra: Enzyklopädie der experimentellen Druckveredelung; Birkhäuser Verlag, 2009

[2] Hille, Frauke Helene: Veredlungsmöglichkeiten und Spezialeffekte für Bücher und Broschuren; Diplomarbeit, Hochschule für Technik, Wirtschaft und Kultur Leipzig (FH), Fachbereich Medien, Studiengang Verlagsherstellung, 2008

[3] Murvai, Geza; Ober, Juliane: Inline-Veredelung im Bogen- und Endlosdruck. Bundesverband Druck und Medien, 2007

[4] Printperfection