Digital Print Hits the Bindery - Head On

It’s beyond the shadow of a doubt that digital print has transformed the printing industry. The enormous number of innovations that have been introduced over the past 10 years—both print engine technology and software—mean we’re in a brave new world of workflow and output.

But, what about those folks in…you know, the BINDERY? That little-discussed place where all those weird machines—like cutters, folders, binders and the other—reside? Well, digital has created a fair amount of heartaches for bindroids. It goes with the technology.

The majority of digital printers installed so far have been toner-based, cut-sheet machines. Toner is pretty high-tech stuff. Essentially, its micro-beads of particles encapsulated in a coating, which is melted by a fusing apparatus.

The chemistry and physics of printing with toner dictate that these particles are laid on the substrate and pressed at high temperatures to ensure that they are “fused” with the paper. In many machines, special fusing oil is also deposited on the sheet to assist in this process. This creates some special problems when it comes to prodicing a finished product.

Among the challenges are:

• Toner Cracking

When folding full-bleed sheets with conventional buckle folders, the toner will separate from the substrate along the fold line. This has bedeviled finishers for some time. But it has also created opportunity, as several finishing suppliers have come up with fixes. The best known of these are creasing systems that apply a crease before the fold. Special creasing discs can be mounted on the folder, and there are several folding systems designed specifically for digital substrates.

• The Binding Problem

The fusing oils used by some digital print engines have caused many bindroids to pull their hair out when they discovered that these coatings on the page prevented the standard hot-melt adhesives used for perfect binding from adhering. As you can imagine, this was not a small problem.