Laminating process

Laminating is the process through which two or more flexible packaging webs 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.

Web laminating is used to improve the appearance and barrier properties of substrates.

The choice of the most suitable web laminating process is mainly dictated by the end-use of the product. A number of different technologies are available that cover the wide variety of applications in the food and non-food packaging industries, as well as for the manufacture of technical laminates for the solar energy and insulation panel sectors.

Laminating machinery can be classified according to the type of bonding agent used to produce the laminates. These types are:

• 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
• Dry lamination: where the bonding agent, dissolved into a liquid (water or a solvent), is applied to one of the 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 strength 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.

The resulting laminated web is then rewound into a finished roll.

BOBST laminator machines range are tailored to the specific requirements of converters in order to fulfill the demand for maximum quality and efficiency. The range of laminating machinery available covers duplex, duplex tandem, and triplex solutions, and provide the kind of functional, operator-oriented, waste-saving and eco-friendly technical solutions needed by industry to achieve the fastest and most consistent levels of performance.