Book Block
A type of document construction in the form of a set of folded sheets or sections which are bound together with no cover. Book block elements: inner pages, inserts, endpapers. The book block of passports/travel documents is usually formed by inserting folded sheets in each other. A thread, a metal staple or a thermo thread are used for binding book blocks. A book block has a top edge, a bottom edge and a fore edge. After cutting, the corners of a book block may be square or rounded.
Fig. 1. Forming a book block by inserting folded sheets one into another
a
b
c
Fig. 2. Kuwait. Special passport issued in 2017:
a — a top edge, a fore edge and a bottom edge of the book block; b — the same. Top edge; c — the same. Bottom edge. Book block elements: endpaper, inner pages inserted one into another and sewn to form the spine