Laminating adhesives are used for large-area bonding of individual foils and films to form laminati, kot je PET/PE ali PET/AL/PP. Lastnosti posameznih folij in filmov so združene tako, da je laminat primeren za kasnejšo uporabo kot embalažni material za pakiranje blaga, kot so na primer živila, zdravstvena nega, medicinski ali farmacevtski izdelki ali predmeti, ki pred prvo uporabo potrebujete zaščito pred poškodbami.
Lepila za laminiranje most often consist as a rule of isocyanate group-containing polyurethane binders. Most of the available laminating adhesive give, after cross-linking, are transparent appearance.
Zaradi zakonskih predpisov je dovoljeno oziroma primerno za uporabo zelo omejeno število surovinfleksibilna lepila za embalažo. Besides their damage to the environment because of the high content of volatile organic solvents, the necessity of high energy consuming drying tunnels to flash-off those solvents to achieve the demanding prooperties, even the necessary adhesive lay down needed for the production of the laminates is about two times higher than the lay down regarding solvent-free adhesives. The laminating adhesive must also be resistant to an effect called "tunneling". which is the localized separating or delamination of the substrates caused by two films of different extensibility that stretch or relax at different rates. Other general considerations in selecting an adhesive for lamination include adhesion, mechanical bond strength, formulating flexibility, and heat and chemical resistance. One must also determine the ability of the adhesive to flow uniformly over the film's surface and form a smooth continuous coting.
