Pressure sensitive adhesives

Pressure sensitive adhesives are one commonly used method to create laminates. Though not always providing the best of bonds, it has value in situations where the substrates to be laminated require a comparatively benign approach. Pressure sensitives (often called peel-and-stick adhesives or psa’s) can be had in roll form, in a range of formulations and

coat weights, and can be applied to a variety of materials utilizing simply, as the name implies, pressure to cause them to adhere. The release paper or film (a customary and essential component of many psa’s) can then be removed to allow the adhesive to be applied to the secondary substrate and, voila!, the two materials are stuck together.

One problem with psa’s is the unrealistic expectation that many consumers bring to their judgment of these products. Over the years, the manufacturers of psa’s have done an exceptional job of creating psa tapes to meet a variety of consumer needs, and consumers have come to expect their “sticky-back” tapes to meet what are, in fact, contradictory performance requirements.

When we apply a piece of pressure sensitive tape to some surface, we expect it to stick – permanently …unless, of course, we need to reposition it a little bit, in which case we expect to be able to remove it with facility and with no adhesive residue, and then reposition it for a new “permanent” bond. Or, as is often the case, we expect to be able to remove it much later (after it has served its purpose), and we again expect to be able to remove it with facility and without adhesive residue.

It’s almost as if we expect the adhesive to “know” what our intentions are for its performance and to adapt to those changing expectations. While this is a credit to the manufacturers of those adhesives, they, themselves, will advise that these are unrealistic expectations.

The selection of a pressure sensitive adhesive must necessarily be a well-considered process. When the adhesive is selected on the basis of its affinity for the surfaces to which it is to be applied, one may well get these near “magical” results.