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The Advantages of PUR Adhesive Binding

PUR (polyurethane reactive) adhesive is the strongest, most flexible binding adhesive available. At Seidl's Bindery, we use PUR adhesive exclusively for all adhesive binding applications. Here are a few additional details about the advantages of PUR adhesive:
  • The page pull strength of a PUR-bound book is more than 2-1/2 times that of a standard perfect-bound book using EVA (ethylene vinyl acetate) adhesive. Books bound with PUR glue simply will not fall apart, even under heavy usage in the most demanding conditions.
  • The composition of PUR glue enables it to form a strong bond with the paper even in the presence of inks, coatings and varnishes. This is in contrast to standard perfect binding, where coatings must be kept free from the spine area prior to binding. Another major advantage of PUR is its flexibility once cured. PUR offers much more flexibility than traditional binding adhesives, and PUR-bound books have flexibility approaching that of "layflat" binding techniques such as Otabind.
  • PUR glue is impervious to temperature extremes. Once it has cured, PUR remains stable in temperatures ranging from -40ºF to over 140ºF. That means PUR-bound books can be used anywhere - from the hottest Texas heat to the most frigid Minnesota winters - without unwanted remelting or cold cracking.
  • Unlike standard perfect binding adhesives, PUR requires several hours to cure once books are bound. Although many companies prefer to let books cure for a full 24 hours before performing subsequent operations, some newer PUR formulas require significantly less curing time. Our experience at Seidl's Bindery has been that books have a bond of 80% grain strength after a curing period of four to six hours, which is sufficient time to begin shrink wrapping and shipping.
The Seidl Advantage
The key to the success of a PUR binding project is to plan it carefully prior to the start of production. Involve Seidl's Bindery early in the job planning process to be sure the end product will meet your expectations. PUR adhesive binding is our specialty; let us put our capabilities to work for your next project!