Perfect Binding Process
Sewn Binding Process
Perfect binding is often used, and gives a result similar to paperback books. National Geographic is one example of this type. Paperback or soft cover books are also normally bound using perfect binding. They usually consist of various sections with a cover made from heavier paper, glued together at the spine with a strong glue. The sections are milled in the back and notches are applied into the spine to allow hot glue to penetrate into the spine of the book. The other three sides are then face trimmed. This is what allows the magazine or paperback book to be opened. Mass market paperbacks (pulp paperbacks) are small (16mo size), cheaply made with each sheet fully cut and glued at the spine; these are likely to fall apart or lose sheets after much handling or several years. Trade paperbacks are more sturdily made, with traditional gatherings or sections of bifolios, usually larger, and more expensive. The difference between the two can usually easily be seen by looking for the sections in the top or bottom sides of the book.