Lamination is the process where two or more independent webs are joined together into a single web. This can be done using liquid adhesives (adhesive lamination), wax (wax lamination), or melted plastic resin (extrusion lamination). There are three types of adhesive lamination systems for flexible packaging – water based, solvent based, and solvent-less. Of these three, solvent-less is the dominant technology, and also what we utilize at Multifilm Packaging.
 

Solvent-less lamination leads the industry for a number of reasons. First, the bonds created with solvent-less adhesives between the laminated webs are 100 percent destruct in almost all cases, minimizing the risk for delamination or other issues associated with weak or poor bond strength. Second, the adhesive requires to drying. It is a two-component system, similar to epoxy glue, where a chemical reaction between the components cures the wet adhesive over a relatively short period of time, typically 12 to 24 hours.

With water-based or solvent-based systems, the wet adhesive must dry prior to joining the two webs, and this requires a relatively large amount of energy using forced hot air. Third, as the web requires no drying, the line speeds are not limited by drying capacity, and the machines typically run at full speed on every job, maximizing the productivity of the machine.
 

Water based and solvent based adhesive systems are still widely in use in the industry, but the number of new machines being implemented in the flexible packaging industry is very low compared to solvent-less. As these machines age, they are being replaced primarily by solvent-less machines, unless the end use application specifically requires either water based or solvent based adhesives.