6 Points to Clarify in Post-Printing Hardcover Binding Techniques
To ensure harmony between printing and post-printing processing, meticulous design and arrangement of printing activities are essential from the outset. Several points require attention during production. Here is a brief discussion for reference purposes only.
Folding
Since the ink pigments on digital prints only adhere to the surface of the paper, folding processes are prone to cracking. Therefore, crease lines should be pre-folded before folding.
Lamination
Laminating the surface of digital prints, especially after printing large solid areas, helps protect the prints during post-printing processes, particularly cutting or packaging. Single-side lamination of double-sided prints may not be advantageous, as the unlaminated side may be more susceptible to ink pigment peeling due to friction during subsequent processing.
Saddle Stitching
Saddle stitching is often a preferable choice for most digital prints, especially for thin booklets such as guides, brochures, and pamphlets. This binding method is cost-effective and can be integrated with other processing methods, facilitating simultaneous pagination, folding, binding, and inline trimming in post-printing processes, thereby guaranteeing the swift delivery demanded by digital printing.
Perfect Binding
When designing perfect-bound booklets, attention should be paid to leaving sufficient binding space between the spine and the text. For instance, when using O-type spiral binding with a ratio of 3:1 (three holes per inch), a 3/8-inch blank space should be left; whereas for a 2:1 ratio, a 1/2-inch blank space should be left. Most computer design programs do not account for the slight changes in paper thickness after printing. In digital printing, the ink pigment deposited on the paper surface can cause variations in sheet thickness. When binding several digitally printed sheets together, the cumulative thickness change may render the meticulously calculated binding dimensions meaningless.
Wire-O Binding
Similar to offset printing, wire-O binding of digital prints also requires consideration of trimming allowances for binding. Apart from leaving a 1/8-inch millback margin on the spine, a 1/8-inch trimming allowance should also be left on the other three sides of the book. Additionally, a 1/4-inch glue-free zone should be left at the bottom of the book cover to prevent glue from seeping onto the next book during binding. Wire-O binding also necessitates bleed covers slightly larger than the text size.
Wire-O Hardcover Binding
The key to hardcover binding lies in securely bonding the book block with the hardcover, producing books that can be preserved. Although the cost and time required for wire-O hardcover binding may seem disproportionate to digital printing, some post-printing binding companies offer prefabricated hardcovers in various colors, styles, and sizes commonly used in digital printing. Therefore, wire-O hardcover binding has become a popular binding method in the digital printing industry.