After the positive market response to the introduction of NEP-free, VOC-reduced primers, Jowat has also launched a new adhesive for window profile wrapping, as the enterprise had already announced several months ago (cf. BAUELEMENTE BAU 3/16, p. 52). With significantly improved characteristics such as a broader range of adhesion, the new adhesive comes as response to the increasing variety of substrates and decor materials used in PVC window profiles and to wider variations in the surface tension of decor materials. The new PUR hot melt represents a consequent improvement and complement of tested and proven adhesives. Individual customers are already using the adhesive in serial production and are impressed by the superior bonding results provided in combination with the new primers.
The new adhesive is part of Jowat’s product series for window profile wrapping. Processors can choose the most suitable adhesive for their individual process parameters from a portfolio with products from medium to very fast crosslinking and from low to high viscosity. The adhesives can be processed with conventional as well as with NEP-free primers. All combinations are certified according to RAL-GZ 716 and meet the requirements for increased resistance to hydrolysis.
Response to increasing requirements
New, more rigid foils used in PVC window profile wrapping require adhesives with very special properties. The newly launched adhesive is characterised by a high initial strength which has been adapted to foils with high restoring forces, and ensures a strong bond between the foil and the window profile on units with short pressing zones or pressing times. Due to the broader range of adhesion, the PUR hot melt provides an optimum adhesion to substrates such as PVC and aluminium profiles for windows and doors. In addition, this is the first adhesive to facilitate an overlapping bonding on the acrylate surface of the window foils. Due to the substantially reduced open time and the related higher initial strength of the adhesive, the laminating speed can be increased without any loss of process reliability.
Higher process stability in combination with new primers
In combination with the latest generation of Jowat primers, the new high-performance adhesive impresses with excellent processing characteristics and facilitates extremely stable processes. The crosslinking speed is increased only during the laminating process when the PUR adhesive comes into contact with the reactive components in the NEP-free primers. Therefore, after just 24 hours, the laminated window profiles are ready for downline processing.
Due to the low viscosity of the adhesive, the optimum temperature for melting and processing of the new PUR hot melt is about 120 °C. Plastic foils are therefore exposed to less thermal stress and stretching during the laminating procedure. The low processing temperature facilitates shorter production cycles, increases energy efficiency, and significantly reduces the risk of thermal crosslinking of the molten adhesive. Prolonged exposure to heat during downtimes, for instance due to modifications, are therefore no problem. This leads to shorter waiting times, and considerably reduced cleaning and maintenance work.
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 decide to use an adhesive system which provides a maximum of environmental protection and occupational safety.
The professional article is published in the magazine 'Bauelemente Bau 1/17'. You can download the original article down below.