Polyurethane adhesives are suitable for a wide range of applications depending on their technology. Typical applications of adhesives are listed as follows:
Typical applications of reactive polyurethane adhesives in food packaging.
Adhesives based on reactive polyurethanes are indispensable in the production of flexible packaging. Most of this packaging is composed of two or more layers held together by laminating adhesives.
Solvent-based and solvent free PU adhesives lamination are the typical flexible packaging production process. While solvent-based polyurethane adhesives need a drying unit before going through the lamination process, solvent-free polyurethane adhesive can be used without this production step.
Because polyurethane adhesive have high flexibility and bonding strength, they are widely used throughout the packaging industry. Food packaging containing polyurethane adhesive(such as PU adhesive for coffee powder and chips bag) can be used for applications at room temperature and below, but some formulations are also suitable for elevated temperatures such as those found in pasteurisation or retort application (for example flexible packaging of aggressive foodstuff such as fruit juices or liquid petfood).
The technical information provided by the adhesive manufacturer should be followed to ensure complete curing, time, temperature and humidity are the most important factors for the curing process. With the regard to curing conditions, the advice of the adhesive supplier should be followed to avoid the possible migration of primary aromatic amines.
