A ‘total system’ approach for waterborne inkjet
To deliver strong results, waterborne systems need more than just the inkjet ink. Specifically, for drop fixation, resistance properties, and substrate adhesion, they typically require a primer. On top of this, they may also need a coating for protection and extra resistance. That’s why we take a ‘total system’ approach to our waterborne inkjet portfolio, offering resins for primers, inkjet inks, and overprint varnishes (OPVs).
We offer fast curing, print reliable, highly durable, energy-curable (UV, LED, and EB) inkjet inks for applications on both absorbent and non-absorbent substrates.
In particular, energy-curing technology offers an optimal balance between print reliability and durability in the cured film – an advantage over most waterborne systems. The film thickness of energy-curable inkjet inks is also higher than that of water-based or solvent-based inkjet inks.
Because several factors affect performance in energy-curing systems, resin materials must be selected carefully. Specifically, they must ensure very low viscosity in the inkjet ink and good cure speeds. Mono-functional and difunctional monomers are key ink components with low viscosity, while pigment dispersing resins, oligomers, adhesion promoters, and cure speed enhancers provide additional performance benefits. Our portfolio offers them all – enabling the high-performance properties you need. Many of these resins can also be used as OPVs.
The Covestro inkjet portfolio also offers waterborne, energy-curable PUD technology tailored for inkjet. This technology provides a higher molecular weight before cure compared to 100% curable systems, which results in a reduced risk of migration after cure. The low migration potential combined with the lower final coat weight is a real advantage over 100% curable systems for packaging applications.