So the debate rages on, and at one extreme there are those who would have you believe that eco-solvent can’t hold a candle to latex in terms of colour, curing times and environmental considerations. This, of course, is not the case and your choice of printer and ink system needs to be taken on the basis of solid facts rather than print room gossip.

Eco-solvent inks – the facts
Eco-solvent inks are based on non-aggressive solvents, which means they don’t produce the same level of harmful volatile organic compounds (VOCs) in the print room as traditional solvent inks. What they do share with the traditional solvent inks, however, is the ability to print on a wide range of coated and uncoated substrates. This makes them the ideal system for outdoor sign applications, as the ink is waterproof, abrasion resistant and long-lasting.

Fact versus fiction – the colour gamut
One of the great advantages of using an eco-solvent ink system is that it can offer a wider colour gamut than latex. As well as the standard CMYK, eco-solvent inks are available in light cyan, light magenta, light black, orange, green, violet, white and even silver or metallic. Typically, you can expect brighter colours and a glossier finish than with latex inks. The reason for this is that eco-solvent inks interact directly with the substrate, so when printed onto a glossy surface the glossy property is retained. In contrast, latex inks lie on top of whatever surface they’re printed onto, giving a matt finish.

Fact versus fiction – durability
If you’re printing for outdoor applications, you need an ink that can withstand the elements – rain, wind and sun can make outdoor signage look faded and tatty far too quickly if you’ve used the wrong inks or substrate. Eco-solvents offer a solution. Take, for example, Mutoh’s Eco Ultra, Universal Mild Solvent (UMS) and MS Ultra inks. These are all subjected to the company’s own stringent durability testing. A panel of three tests includes assessment for abrasion resistance, chemical resistance and outdoor durability. All Mutoh’s eco-solvent inks are highly durable in comparison to latex inks, which require lamination to extend their lifespan.

Fact versus fiction – it’s like watching paint dry
The popular belief is that latex inks dry instantly and eco-solvents take hours. It’s certainly true that latex prints come out of the printer already dry. But the time required for eco-solvent inks to outgas must be factored into the quality considerations of choosing one ink over the other. Curing times vary depending upon the substrate, saturation and application of the ink. Good time management of the production process can make this a moot point anyway and the quality gains quickly outweigh the time considerations. Furthermore, eco-solvent prints can be cured with heavy ink loads across the whole usable area of the media. This is not always the case with latex prints, which can result in wastage around the outer margins.

Fact versus fiction – the environmental issues
Solvent inks have a bad reputation for releasing VOCs into the atmosphere. Eco-solvents, however, are formulated using non-aggressive solvents. Additionally, these thicker inks contain more pigment, meaning that less ink is needed. Latex inks are cured as they go through the printer – and this creates its own environmental issues in terms of the amount of energy they use to do this. It’s also worth noting that Mutoh UMS inks have been awarded an Indoor Air Comfort Certificate, proving that they meet the most stringent EU requirements for indoor air comfort after installation.

When it comes to deciding on a new printer and ink system, the most important thing is to ascertain the facts about each system and then work out which one would be best suited to your production needs. If you’re not sure, the team at SEDO would be happy to help you come to the right decision.