Appretur

The physical characteristics of wood-based materials such as MDF and HDF can be improved significantly with the Jowapur^® Appretur. This provides the opportunity to tap into new markets and fulfil the increasing requirements for the latest applications, and to achieve higher resistances.
Especially the tensile strength, shear strength, bending strength, E modulus and transverse tensile strength can be increased by up to 100 %.
The application amount and therefore also the achievable improvement are depending directly on the material thickness, density and penetration depth.
The Appretur is applied in a curtain coating process and drawn into the board through vacuum. The penetration depth can be adapted by changing the application amount, the vacuum and the duration of the process. Depending on the purpose, only the surface with a few millimetres of penetration into the material or a complete treatment may be necessary.
Materials treated with an Appretur can be bonded easily with different adhesive systems. Superior bonding strengths are achieved with dispersion adhesives directly after the treatment (wet in wet).

Depending on the quality of the laminate, the appearance of the joints may become unattractive after some time. Firstly due to the ingress of moisture causing a swelling of the MDF substrate and secondly due to a movement of the individual rows of planks in the longitudinal direction. The Appretur is especially suitable for the Laminate flooring industry in combination with a vacuum spraying application to ensure a homogeneous and complete coating of the tongue and groove of the laminate and to facilitate a permanent superior appearance of the joints.
Using the vacuum spray technology, Jowapur^®-Appretur can be applied easily and extremely accurately even on the profiled edges of wood-based substrates. The standard feed speeds of up to 300 m/min in the flooring industry are no problem for the Appretur. The positive effect and a substantial reduction of edge swelling has been confirmed in tests with low surface tension water. Edge swelling can be prevented almost completely, facilitating a leap forward in quality and permanent customer satisfaction.

Whether with or without frame, the lightweight panels with a paper honeycomb core play an increasingly important role in the manufacture of furniture. The objective of using these materials is to reduce weight and to save resources. The water-repellent properties of the honeycombs and the skins can be improved through an Appretur treatment. One major demand from the industry are boards with an increased carrying capacity. The loading capacity of lightweight panels can be increased significantly with a finishing of the paper core and optionally of the skins.
The Jowapur^® Appretur can be applied by roller on the ridges of the honeycombs. This reduces the material consumption to a minimum. For superior results, the substrates may be bonded directly after treatment with a PVAc dispersion adhesive (wet in wet). If the substrates are bonded with hot melt adhesives, the Appretur should dry before bonding. Depending on the requirements, the Appretur may be applied only on the surface or penetrate into the entire cross-section.
The Appretur improves the performance of lightweight elements, especially with regard to the tensile strength, bending strength and the transverse tensile strength. Compared to an untreated element, the achieved strength values are much more evenly distributed. This optimisation can lead to a quantum leap in the manufacture of lightweight furniture and opens up new opportunities regarding application and structure, especially since material consumption can be reduced further.