Adhesive application is a crucial step in the binding process, as it dictates the longevity of the book and its pages. The glue is often applied to the spine of softcover and hardcover books, and the type of adhesive makes more of a difference than one might think. Two common adhesives used for perfect binding are EVA and PUR—and there are good reasons to choose one over the other.
EVA (Ethylene Vinyl Acetate) is a traditional hot-melt option known for fast cure times that support quick turnarounds. Advantages include crack resistance, resilience, durability, UV resistance, and light stability. EVA is generally best for standard, uncoated offset stocks and simpler applications; it’s not recommended for thicker or more challenging coated stocks.
PUR (polyurethane-reactive) has grown in popularity thanks to its strong bonds and attractive, clear-dry finish. It’s a moisture-curing adhesive, so systems must be sealed when idle to prevent exposure to air. While PUR is typically more expensive, you often apply about half the film thickness versus EVA. Note: MDI can be emitted during curing and should be monitored with appropriate controls.
EVA is cost-effective, easier and safer to run, and produces minimal waste since it can be re-melted. However, the re-melt property means EVA can soften in extreme heat and become brittle in extreme cold. It’s a solid choice for thread-sewn books and many standard projects.
PUR generally delivers higher bond strength, great lay-flat performance, uses less adhesive, and dries clear—but requires tighter process control and equipment maintenance to avoid premature curing.
There’s no one perfect answer. Consider book thickness, stock/coatings, end-use environment, throughput goals, and budget when choosing an adhesive.
