| Medieval books were typically written on such thick paper that there was no need for a separate book cover. Titles were simply written on the "front" of the outermost sheet. However, by the Edo period, there had come to be a demand for formal covers, both for decorative/aesthetic purposes, and also in order to make the book seem like a more precious, and thus prestigious, object. Covers quickly became standard. Still, book covers, particularly on ''fukurotoji'' books, were made of simple paper, or paper lining a somewhat thicker piece of card-board made from recycled paper. These outer covers were often burnished with a sizing material called ''dôsa'' (礬水), made from alum and hide glue, which provided some protection for the books; covers were also often embossed, printed, painted, or burnished with simple patterns. These patterns were, sometimes, used exclusively by a single publisher, thus marking the book as having been produced by that publishing house. A paper slip known as a ''gedai'' (外題, "outside title"), affixed to the front cover, often gives the title of the book, along with other information, such as the volume number within a series. | | Medieval books were typically written on such thick paper that there was no need for a separate book cover. Titles were simply written on the "front" of the outermost sheet. However, by the Edo period, there had come to be a demand for formal covers, both for decorative/aesthetic purposes, and also in order to make the book seem like a more precious, and thus prestigious, object. Covers quickly became standard. Still, book covers, particularly on ''fukurotoji'' books, were made of simple paper, or paper lining a somewhat thicker piece of card-board made from recycled paper. These outer covers were often burnished with a sizing material called ''dôsa'' (礬水), made from alum and hide glue, which provided some protection for the books; covers were also often embossed, printed, painted, or burnished with simple patterns. These patterns were, sometimes, used exclusively by a single publisher, thus marking the book as having been produced by that publishing house. A paper slip known as a ''gedai'' (外題, "outside title"), affixed to the front cover, often gives the title of the book, along with other information, such as the volume number within a series. |