Film Lamination is the process through which two or more flexible packaging films are joined together using a bonding agent. The substrates making up the webs may consist of films, papers, or aluminum foils. In general terms an adhesive is applied to the less absorbent substrate web, after which the second web is pressed against it to produce a duplex, or two layer, laminate.
Laminating types can be classified according to the bonding agents used to produce the laminates:
- Dry lamination: where the bonding agent, dissolved into a liquid, is applied to one of webs, before being evaporated in the drying oven. The adhesive coated web is laminated to the other under strong pressure and using heated rollers, which improves the bond strengh of the laminate.
- Solventless lamination: where the adhesives used do not contain solvents. Solventless adhesive generally indicates a specific type of adhesive composed by two components reacting with each other and consequently not requiring drying.
- Wet lamination: where the bonding agent is still in a liquid state when the webs are joined together. It is commonly used to produce a paper-aluminum foil laminate that is widely used in flexible packaging.
