PUR adhesive is an alternative to the traditional Hot Melt adhesive. PUR Adhesive will enhance the performance of any book by giving it greater strength. PUR is gaining in popularity among printers because of its superior qualities and is now being used more than traditional hot melt adhesives.
PUR Superior qualities include:
Excellent Lie-Flat Qualities
The grain of your cover stock should run parallel to the spine. Covers that are wrong grain tend to crack on the backbone scores and do not have a square-looking spine.
Heat and Cold Resistance
Books that are wrong grain can have numerous problems. Books that are bound with Hot Melt adhesives are difficult to open or lay properly and have a lack of durability. Users push the book open to read the copy in the spine area, which in turn weakens the book even more: pages fall out or weak page pulls occur. PUR Adhesive will bond to cross grain stocks. Graphic Finishing Services binds all books with cross grain stocks with PUR Adhesive for durability and peace of mind.
Less Wrinkling of Backbone
The covers should be 1/16th” longer for the head trim and 1/8th” longer for the foot trim. The covers when stripped should be stepped ¼” longer then the longest signature to eliminate backbone glue adhering to the nipper station and transferring spine glue to the next book.
Square Backbone
It is best to create a dummy using the same paper stock to be printed. Hot Melt glues do not adhere well to inks or coated surfaces, but PUR Adhesive does.