Keep It in the Film!
Here’s an interesting question. Is coating a part of traditional finishing?, And what about laminating? Why not? Applying any treatment to the substrate qualifies as part of the finishing process. And coating and laminating certainly play key roles in making print more presentable and durable.
UV-curable coatings can be applied to selective areas of the media (spot coating), or to the whole sheet. UV coatings are relatively easy to apply with the wide variety of machinery, and not only provide some protection for the media, but they will enhance the appearance of the sheet and provide more “pop” for the color work.
Laminating takes this a step further by bonding a self-adhesive film to the media surface. Laminating films come in dozens of different types for different applications (offset, digital) and it’s widely used in book printing for protecting soft-cover book covers. But it’s also widely used for membership cards, manual covers, maps, retail signage, POP displays and many other products.
Both coating and laminating film suppliers have been challenged by the advent of digital print, since toner particles basically “stack” on the paper surface as opposed to being absorbed (as with offset inks). Applying too much heat to the substrate surface in the laminating process can smear the toner print. Laminating films that activate at lower temperatures have been developed to address this issue.
Perhaps the most interesting coating development has been the rise of “pre-coaters” for continuous inkjet presses. Inkjet is a rising digital technology, but it cannot be used on all substrates. Getting the most out of inkjet requires not only tuning the ink and print heads, but using the right paper. In an effort to improve inkjet’s appearance on various substrates, many presses will now apply a “pre-coating” to the web immediately before the inkjet print heads. The pre-coating improves the paper surface, making it more receptive to the picoliter dots from the print heads. The fact that this pre-coating is part of the press makes it even more efficient.