Researchers in Spain have found a way to combine standard offset inks with inkjet technology. At a stroke this would break the cost barrier that is considered a major impediment to the transition from offset to inkjet printing. The ink would also break restrictions around the supply of ink, which currently must come from the company that provided the press and would create an open market as exists in litho printing where the printer is free to choose which ink to use. The price of ink, described as the most expensive liquid in the world at one point, would crash.
The development will also make colour management easier, especially when trying to match between processes with different colour gamuts as the new inkjet ink would match the long established litho inks.
The researchers from the Universidad Catholic de Abril Uno in Toledo have been working on the project for almost a decade and have reached the point where the ink has been made available to inkjet press suppliers for their own testing. There are hopes that commercial availability could begin from Drupa in 2028.
The challenge has always been to find a way to reliably pass the highly viscous litho ink through the ultra fine nozzles of an inkjet printhead. Inkjet ink by contrast is mostly composed of solvent or water to carry the pigment or dye to the substrate, which then creates problems as the water has to be removed. This is one of the biggest issues in inkjet printing today. The development of printheads able to handle more viscous fluids, pioneered by Xaar, is not enough to cope with the universally available ink sets.
Switching to an offset ink would side step these restrictions. The first implementation according to the Spanish boffins will be a heatset style ink which is markedly less viscous than a sheetfed ink and would utilise the dryers used in today’s inkjet presses. However, the team, led by Professor Xavier Fuld-Yu-Mucho, believes that the underlying approach will suit all litho inks, provided the pigment used has been ground to the nano particulate size needed to pass through the printheads.
The approach from the university’s cuckoo chemistry department separates the resin and varnish components from the standard ink. This is applied ahead of the ink to the paper, acting like a primer for the ink protecting the pigment when reaching the paper. The carrier fluid in the ink uses both oil and additional water, which can come from the printer’s own mains supply, to reduce the viscosity to the required thickness and to ensure that the ink flows through the piezo nozzles without impediment. And because the oil based ink and water do not mix, they separate after firing so no water is carried into the paper.
Fuld-Yu-Mucho says in a statement: “This is the holy grail. When we started I felt like Don Quixote tilting at windmills, now we are more like El Cid banishing the tyranny of high inkjet ink prices from the land.”
The development will disrupt the razor and razor blades business model that is used across digital printing. If printers are free to choose ink from anywhere, the suppliers will not be able to rinse printers. Inkjet printing will become considerably less expensive. No supplier wanted to go on record when asked about the developer, but one summed up the general feeling with a brief comment explaining: “Oh Sheet.”
