Benign Adhesive Concepts for Postal Service Applications, 2000 Recycling Symposium Proceedings

Kim K. Tsujimoto, Dave Kramlich--The USPS sells billions of stamps every year to consumers, small businesses and bulk mailers; currently these stamps are predominately self-adhesive, on a liner. For stamp users, these self-adhesive stamps on a liner have been easy and quick to use, and have offered consistent adhesion. For recyclers, however, these adhesive stamps have caused concern for their paper recycling processes. In addition, there is the issue of the stamp construction which consists of a liner which may not be recyclable (the USPS estimates there is 60-65 billion square inches of liner used in PSA stamps annually). In 1995, the USPS initiated a program to qualify different environmentally benign postage stamp constructions. At this time, there was not a universally accepted method for testing or measuring the effect of adhesive products on the paper recycling process or on the finished recycled paper product. The USPS, together with Specialized Technology Resources (STR) and the Forest Products Laboratory (FPL), have developed laboratory, pilot, and mill scale trial procedures and test methods to quantify the different stamp constructions. After the first three phases of the USPS Environmentally Benign Adhesive Program, 14 adhesives continue to meet, or exceed, the USPS specifications for stamp performance and recyclability. This paper describes the development and testing of 3M’s adhesive submissions to this USPS program. ______________________________________________________________________