Today, we expect a modern windows or entrance door to last around 25 to 40 years.
- PUR hot melt for exterior applications
- Certified adhesive-primer systems for PVC profiles
- VOC-reduced primers specific products for PVC window profiles
Adhesives for window profiles
Within this time, the windows and doors should operate without problems and look good, which means that the laminated foil and the bonding system should not separate from the PVC or aluminium profile, even if the exposure stress due to climate conditions is extreme.
For lamination of window profiles, the PUR hot melt adhesives have proven for decades now to be highly suitable. Continuous further development of the foils used, the steadily increasing variety of materials and decors, and also the reduced storage time for the profiles after lamination – all of these factors represent more challenges for the adhesives. This is why today, we need adhesives that adhere to a multitude of different materials with fast crosslinking, which allows immediate downline processing of the laminated profiles.
The reactive hot melt 604.20 has been supplied by Jowat for several years. The extremely fast crosslinking of the adhesive facilitates short interim storage times before further downline processing steps.
- fast crosslinking
- can be applied at low temperatures (≥ 115 ºC)
- downline processing after 6 – 8 hours
The new product Jowatherm-Reaktant® 604.25 represents a consequent improvement of this system, characterised by an improved adhesion spectrum, shorter open time and higher initial strength. The product ensures a reliable bond between foils with high restoring forces and the window profile, even on units with short pressing zones and pressing times. The increased range of adhesion of this PUR hot melt adhesive provides optimum adhesion on PVC and aluminium profiles for windows and doors. In addition, overlapping bonding is now for the first time possible on the acrylate surface layer of the window foil. Due to a significantly reduced open time, the speed of the laminating process can be increased without affecting the process stability.
- suitable for PVC and aluminium profiles (with a proper surface treatment)
- overlapping bonding on acrylate layer possible
- increased resistance due to improved thermal stability
- faster processing due to short open time and high initial strength
- low processing temperatures (≥ 120 ºC)
- high hydrolysis resistance
- downline processing after 24 h in combination with Jowat® 406.84
The new high-performance adhesive combined with Jowat primers of the latest generation provide extremely stable processes and excellent processing characteristics. Only when the PUR adhesive comes into contact with the NEP-free primer during laminating, the reactive components in the primer accelerate the crosslinking process, allowing a downline processing of the laminated window profiles already after 24 hours.
Through the new addition to the Jowat portfolio, processors have the opportunity to choose the most suitable adhesive depending on the individual process requirements. The powerful adhesive system consisting of Jowat primers and adhesives represents the perfect product mix with regard to processing characteristics, process reliability, and process efficiency. By choosing the latest generation of NEP-free, VOC-reduced primers from Jowat, processors additionally support a maximum of environmental protection and occupational safety.
In combination with the new primer Jowat® 406.84, these adhesives do not only provide a very high initial strength, but also the advantage of using a VOC-reduced, NEP-free primer without hazardous material labelling. This is part of Jowat’s responsibility in the interest of sustainability in protecting employees and the environment. Apart from these aspects, the combination primer / adhesive also leads to convincing superior bonding results, and of course meets the requirement for peel strength of minimum 3 N/mm according to the new RAL-GZ 716. The standard grammages for the adhesive application usually run from 40 to 70 g/m². For the respective machines in use, the various process parameters, as well as the profile and the type of foil, preliminary customer trials have to be run to define which adhesive/primer system is most suitable and tailored for the respective process.