Three Covinax pressure sensitive adhesives manufactured by Franklin Adhesives have been certified as “environmentally benign” by the US Forest Products Laboratory, indicating that the adhesives can easily be removed from paper during the recycling process. Franklin adhesives is a division of Franklin International, Columbus, OH, USA.
The certification is in part a result of the division’s joint research project with the University of Minnesota, which was funded by the US Department of Energy, to reduce or eliminate residual adhesive from waste paper during recycling. Residual adhesive adheres to papermaking equipment during the manufacture of paper from recycled paper, leading to machine down time and specks or tears in the final paper products. Franklin Adhesives provided products for testing to the university; the research team found that three of these formulas were easily removed from paper during re-pulping.
The three Covinax products to receive FPL certification are Covinax 324-39, 379-05 and 418-02. All three are also FDA compliant under 21CFR 175.105.
Covinax 324-39 is a vinyl acrylic co-polymer for general purpose permanent pressure sensitive adhesives on tapes and labels. It is used for corrugated substrates, polyolefin films, glass and metals and is easily converted into rolls or sheets without sticky edge problems. This formula can be transfer-coated on most rod, gravure or roll coaters.
The second FPL-certified product, Covinax 379-05, is an acrylic adhesive for permanent pressure sensitive applications, including pharmaceutical label applications requiring adhesion to curved or irregularly shaped surfaces. The balance between peel and shear strength also renders this formula easily convertible to rolls or sheets. It is specifically designed to be transfer-coated on slot die coaters and can be used on most rod or roll coaters.
Food packaging manufacturers use the third certified product, Covinax 418-02, an acrylic emulsion polymer, for low- and freezer-temperature labels on food packaging materials.
“Franklin International was one of the first major adhesive manufacturers to focus on environmentally friendly products more than two decades ago and remains committed to them today,” says Mike Witte, manager of the division’s pressure sensitive adhesives business. “Our partnership with the University of Minnesota, pursuit of certification and active focus on development of additional recyclable formulas are important ways for our company to have a positive impact on the environment.”