Complex substrates, higher packaging speeds and health and safety awareness are often in conflict with each other. Developing packages which include these aspects offer a great challenge. Paramelt succeeds in doing so by formulating aqueous polymer dispersions under the brandname Aquaseal™.
Aquaseal™ formulations are based on unplasticized, high molecular weight thermoplastic ethylene co-polymers which offer the following properties:
- thermoplastic behaviour;
- low sealing temperature (70-90°C);
- high hot tack;
- perfect seal integrity;
- good adhesion to polar substrates (like aluminium, glass, paper);
- tough clear coating; water and chemical resistance; dispersability.
Aquaseal™ can easily be applied via normal coating and printing techniques. To improve adhesion to some filmic substrates a primer, like poly-ethylene-imines, could be necessary. The low sealing temperature combined with the high hot tack are important to maintain good sealing values at high packaging speeds. Aquaseal has shown to fulfil this requirement.
The good adhesion to polair substrates is perfect for applying it to aluminium foil or paper, using it as a sealing medium or to improve adhesion of other polymers, like PE, to these materials. It´s water resistance makes it possible to reduce MVTR or modify Cobb-values of the substrate.