When digital print first came along, few would ever have imagined white ink becoming available and probably fewer still could have dreamed that clear varnish might become a practical reality. Although it might have limited appeal across run-of-the-mill production in ink-jet terms, its addition has brought a definite added value to some applications, and it's thanks largely to the growth of UV-curable ink and its associated technologies that this is now a viable option for many jobs.
Not uncommon in analogue production processes, varnish hasn't been particularly tricky to incorporate into ink-jet machines. Its appeal isn't so much as a glossy finish to an entire job but more as a spot clear, used to lift the visual appearance of specific areas. Its application remained largely non-digital as a finishing process, yet it has always been acknowledged that the addition of clear can produce a premium look and feel to many a dull job.
The advantage of incorporating clear varnish as a special colour, in much the same way as white has been integrated into print-head arrays despite its idiosyncratic behaviour, has led to its successful incorporation as part of the ink-jet process. This has taken its application away from the conventional finishing line and made it part of the printing process, endorsing its ease of inclusion and suitability for short runs. No-one will deny that digital varnishes are more costly than their analogue counterparts but the effects that can be created can bring practical as well as visual benefits to applications.
As well as gloss and matt finishes, varnishes can also be used to create textures on prints so that all sorts of special effects can be generated. Additionally, by applying multiple layers of clear, tactile results can be printed including Braille. This means that specialist packaging,labelling and proofing can meet the necessary EU legislation using ink-jet engines. Likewise, where displays need to adhere to the Equality Act 2010, which largely superseded the DDA(Disability Discrimination Act), this technology has provided a valuable resource to sign-makers who, hitherto, had no means of printing raised textures but had to resort to other means.
Interestingly, both Mimaki and Roland have incorporated their clear options into engines that utilise LED curing, proving that the narrower wavelengths haven't caused problems with varnish. This has also reaped the benefits with UV-curable inks able to be used in much smaller platforms than would be possible with their mercury arc counterparts. This, in turn, has brought the benefits of varnish to the industrial and novelty market segments with its inclusion in remarkably low-cost desktop machines which are now proving to provide value-added services to sign-makers, high street print shops and display producers.
Roland DG saw a golden opportunity for incorporating a clear varnish in even the earliest iteration of its VersaUV LEC engine. When this machine first made it to market perhaps its destination was a little vague because it was obviously not a standard sign-making or display printing platform. Nonetheless it wasn't long before its talents in the proofing and specialist labelling segments came to the fore, aided by integrated cutting in typical Roland style. Subsequent versions of the company's UV-curable printers now include clear, even down to the compact LEF-12 desktop model.
More recently Mimaki has added a clear varnish to its hard UV ink sets, embracing its JFX and UJF printers and bringing a useful option to those who want to add gloss or matt special effects to applications. Not surprisingly, the UJF-6042, bigger brother to the UJF-3042, also sports white and clear, bringing a more generous bed size to a desktop machine and extending the ability to print nested and step-and-repeat jobs.
Looking at the evolution of clear varnish in our market sector, although it's been available as an option in more industrial-strength wide-format machines, probably where it has really come to the fore is in the smaller ink-jet formats. Additionally, it can hold its own in prototyping for packaging both from a visual viewpoint and where tactile requirements need to be met.
In conjunction with printed labels, promotional goods and industrial products, the use of clear varnish plays a double role. It not only provides a visually appealing finish but it also acts as a tough extra layer that protects against scuffing and scratching. Its inclusion isn't difficult as part of an ink-jet file's workflow, and libraries of textures make special effects simple to apply, resulting in jobs which add a good element of visual and tactile appeal.