This format yields 36 pages per signature and results in a distinctly small, pocket-sized book. Because eighteen does not divide evenly by simple binary folding, the imposition requires a complex folding scheme or cutting off a section of the sheet before folding. It is historically used for compact editions and religious texts.
The client wants a pocket diary, so an 18mo format should give us the right dimensions without wasting paper.
Also heard as
- octodecimo
Related terms
Signature
A large printed sheet folded multiple times to form a sequential section of a book.
12mo
A book format created by folding a printed sheet into twelve leaves.
32mo
A miniature book format produced by folding a printed sheet into thirty-two leaves.
Imposition
The arrangement of pages on a press sheet to ensure correct order after folding and trimming.