There are a number of different processes involved with binding books. One of the most popular being perfect binding. This type of binding is used primarily in softcover publications.
Perfect binding is a process in which multiple pages are glued together using a strong but flexible thermal glue. The cover is then folded around the spine. It is then trimmed on three sides giving it a clean professional look.
The spine-side of the multiple pages are roughened. This allows the adhesive to leak into the paper fibres for stronger adhesion.
Two Types Of Perfect Binding
There are two types of binding. They relate to the strength of the binding itself and the adhesive used.
The first type is standard perfect binding. This uses an adhesive called EVA (ethylene vinyl acetate.) The second type of binding is PUR (polyurethane reactivate) binding that uses a stronger adhesive (up to 40% stronger in most tests).
PUR dries faster and allows the book to lie flatter. It also uses less adhesive. It can adhere to many different substrates including, various inks, UV-cured coatings, aqueous coatings, coated papers and boards in a variety of weights and films as well as traditional uncoated papers. However, PUR binding is more expensive (about 30% more in most cases) than standard perfect binding.
PUR binding is ideal for jobs such as a 96pp recipe cookbook where people tend to push down on the spine when the book is opened to keep open the page they require.
Although PUR binding is superior in most applications standard perfect binding does have its place with magazines and light weight uncoated papers for book binding.
It’s interesting to note that the binding process for PUR binding is exactly the same as perfect binding. The only thing that changes is which adhesive is used (Standard EVA or PUR adhesive).
Choosing whether to use perfect binding or PUR binding should be based on which process is most suitable for your outcome. Considerations such as budget, intended usage, substrates involved and thickness of the book will all impact the best option.