October 2004: Case Binding – A Strong Solution

At The Riverside Group, we’re able to deliver handsome casebound books in a variety of methods to meet your durability needs.

Case binding is an excellent solution for books that require durability combined with a classic and sophisticated look. At the Riverside Group, we routinely perform case binding for projects such as cookbooks, manuals, diaries and promotional materials.

There are three case binding styles available at The Riverside Group; the book's design and durability requirements help determine the best one for a specific project. Here are some details about each, along with some helpful planning tips to keep in mind:

Strong: PUR adhesive binding – Originally created for use in airplanes and automobiles, PUR (polyurethane reactive) glue is the strongest bookbinding adhesive available. PUR adhesive binding is a great choice for case-bound books with a great deal of images or graphics, as PUR adhesive provides excellent spine strength on signatures with heavy ink and coating coverage.

Stronger: Thread sealing – Performed inline on a folder, thread sealing mixes thread pieces with adhesives to create an incredibly strong bind. Thread sealing is best suited for projects with limited ink coverage on uncoated sheets.

Strongest: Smyth sewing – Probably the strongest and most durable perfect binding style, Smyth sewing is a process of weaving threads through the signatures of the book block from head to foot. Binding adhesive is then applied to the spine for additional strength by locking the signatures together. Smyth sewing is ideal for case binding projects that are designed for long-life, heavy-use applications.

Planning Tips
Grain-parallel is critical: Print your signatures with the grain direction of all pages parallel to the bind to prevent wavy, weakened spines. Pages will expand after binding as moisture enters the paper fibers. Paper grain bound perpendicular to the spine will be restricted from this natural expansion, causing distortion to the spine and individual pages. This can result in a misshapen and damaged book.

To perf or not to perf?: It's common practice to perforate the spine on folded and gathered signatures to remove air during binding. However, signatures should not be perforated if a case-bound book will be Smyth-sewn. Spine perforations eliminate the ability to sew thread through the spine.