There are two main kinds of adhesives used in book repair: paste and glue. Each has special properties and should be used in specific instances.
1. BOOK REPAIR PASTE
Paste is generally a cooked mixture of water and vegetable starch, such as wheat or rice.
2. BOOK REPAIR GLUE
Several types of glue have been used in bookbinding over the years, the most common being animal hide glue. In recent years, animal-based glues have been replaced with synthetic vinyl resin glues, the most common of which is polyvinyl acetate emulsion (PVA).
Should I Use Glue or Paste?
Using glue will give you a quicker drying time and a permanent (non reversible) adhesive fix for your book repair. This is a good option for loose pages in a paperback book where the initial adhesive has cracked/dried following years of use. Glue should not damage the pages.
Using paste will take a longer time to dry but will be a stronger fix and the paste will penetrate the fibers of the paper. Paste repairs can usually be reversed if needed but the moisture content of the paste and the longer drying time can buckle the paper pages being repaired.
Most people learning to repair books use too much adhesive. The belief seems to be that if a little is good, a lot is better. In book repair, that just isn’t true. A thin, even coat of adhesive makes the best bond. Too much adhesive will ooze out of the edges of a repair and stick to the pages. Also, too much adhesive causes the paper to wrinkle and takes longer to dry.
Watch each repair carefully. If there is excess glue or paste, wipe it away. Next time, try to use less paste or glue. When applying adhesive, choose a brush that matches the size of the surface. When pasting or gluing a small area, use a small brush. When the area is larger, use a bigger brush.