Laurel Brunner: Recycling Digital Prints

Most deinking technologies were developed for conventional oil-based inks. The common deinking methods reflect the traditional print mix, but the rise of digital printing suggests it might be time for new approaches. Change is inevitable and new ink chemistries and substrates will disrupt the established hegemony. As the printing industry produces more and more varied digital prints for applications ranging from commercial print and books, through to signage and textiles, deinking technologies must keep pace.

The deinking problem mainly applies to prints printed with flexo inks, inkjet and some liquid toners, but not all. Prints printed with Xeikon toners, for example, can be deinked using conventional deinking technologies. But what is unavoidable is the fact that the volume of materials produced with print methods that cannot be conventionally deinked is rising and will continue to do so.

Digital printing methods are steadily and relentless encroaching on traditional printing sectors, from packaging through to sign and display work. This requires integrated mills to invest in suitable deinking methods, or face competition from innovators with more imagination and vision. The market for pulp and paper chemicals worldwide could reach $20 billion by the end of 2015. In North America alone, pulp and paper chemical demand is expected to increase to $4.8 billion in 2015. So this is a market ripe for disruption.

One particularly interesting technology for deinking prints is to use enzymes rather than conventional chemistries. Enzymes can be produced biologically from renewable resources. Their use reduces the need for chemicals, lowers the deinking process cost, and uses less energy so enzymatic deinking more environmentally friendly. Enzymatic deinking can also produce stronger papers.

Print buyers and printing companies investing in new print technologies want a vibrant digital printing industry, so such developments are good news. Digital printing is environmentally friendly in that it reduces print waste volumes and has collapsed prepress supply chains. But how can print buyers make environmentally informed decisions about the print method they use to produce their projects? Printers and print buyers can select print methods on the basis of the print’s deinkability, an indicator of its recyclability and suitability for subsequent use as a raw material. Digital press manufacturers are working hard to ensure the deinkability of the prints their presses produce, so as ink, substrate and deinking technologies evolve, we can only expect this to get better.