Heavy ink coverage, flood varnishes and coatings, mixed paper stocks… in many cases, that’s a recipe for perfect binding disaster! For books bound with standard hot melt adhesives, those elements can compromise binding strength and cause books to fall apart easily. If any or all of these characteristics are found in your adhesive binding projects, PUR (polyurethane reactive) adhesive may be your best solution.

How it Works

PUR adhesive cures by creating a chemical reaction with the moisture present in the paper stock and atmosphere. This differs from standard hot-melt adhesives, which cure by shedding moisture. One planning note: The PUR curing process takes a few hours longer than that of hot melt adhesives, so keep this in mind when planning and scheduling your project.

Here are some of the key advantages to PUR binding adhesive:

Strong and flexible - PUR adhesive was originally developed for use on automobiles and aircraft, which should give you an idea of how effective it is for holding books together. PUR is the strongest binding adhesive available, providing page-pull strength several times that of standard hot-melt adhesives. PUR adhesive also provides superior flexibility to hot melt adhesives, making PUR the glue of choice for lay-flat binding methods.

In practical terms, this combination of strength and flexibility makes PUR ideal for even the toughest adhesive binding applications. So go ahead and print your books with full-bleed images and coatings; PUR adhesive will create a strong, long-lasting book despite these traditionally troublesome elements.

Impervious to temperature extremes – Have you ever left a perfect-bound book on the seat of your car during a hot summer day? How about in the middle of winter? These temperature extremes would cause standard perfect-bound books to fall apart as the binding adhesive breaks down. This isn't a problem with PUR adhesive, as it retains its strength even under such extreme temperature conditions.

Page pull machines test how many pounds of pressure it takes to dislodge pages from binding. PUR adhesive consistently ranks as the strongest binding method available.