Using the Right Glue for the Right Application

• Part 1 - Adherence
• Part 2 - Multipurpose Adhesives
• Part 3 - Hot Melt Glue Versatility and Cold Glue Advantages
  • Section 1
  • Section 2
  • Section 3

Today, trade finishers face the challenge of having to select the most effective gluing product for a myriad of specific applications. This results in a constant balancing of pricing and the wide range of product effectiveness. Binderies must select the right glue after considering such factors as the intended end use of the product, the specified coatings or finishes, different types of paper stock, and storage condition. Given these factors, binders also must weigh the cost savings of using lower-priced glue against the possibility of performance failure in a specific application.

Adherence

Glues must be carefully selected to adhere to whatever coatings or finishes have been required by the bindery’s customers. To complicate that selection, the coatings and paper stock that have been used successfully with certain glues frequently change in composition, causing the glues to lose their effectiveness. A plethora of coatings – such as UV, aqueous, and standard varnishes – are constantly changing in composition due to the varying availability of certain chemicals. Some chemicals can no longer be used because of raw material availability, a situation that is out of the binder’s control. The use of different paper stocks, too, changes regularly. Paper stocks range from recyclable paper that is widely used in the printing and carton industries, to standard offset, cover weight stocks, and fluted carton material that are finding wide acceptance in direct mailers, brochures, and information packets. As a result, binderies must deal with a wide range of adhesion issues. For example, flood coating of paper is commonly used in applying certain coatings. This sometimes creates a problem for gluing because these coatings have high resistance to adhesion.

There are several effective ways to combat loss of adhesion. One is to block out the glue able area on the paper. This will create an opportunity for the glue to bypass the coating and adhere directly to the substrates below the coating. If using a block out is not an option, binders can add a glue assist to their existing dies or new dies at the time of die-making.