POLYURETHANE VARNISH MICROCEMENT – The process of applying microcement, as a technical material, needs to follow a few steps to ensure that the result is as expected. In addition to the microcement layers, both the bases and the fine finish, there are two processes that are necessary:
While the bonding bridge serves to improve the fixation of the microcement to the support surface, the varnish serves to improve the final finish. The main functions that characterize polyurethane are:
Les vernis polyuréthane sont essentiellement de deux types: à base d’eau et à base de solvant. Pour des raisons environnementales, la base de solvants est moins utilisée chaque jour, et il existe déjà des pays qui l’ont interdite. Quoi qu’il en soit, même si sa finition était peut-être un peu plus résistante, il est également vrai qu’elle pourrait laisser des traces de rouleaux sur la finition finale.
Le vernis polyuréthane à base d’eau est le vernis le plus utilisé ces derniers temps. Ses propriétés techniques se sont améliorées ces derniers temps, parvenant pratiquement à atteindre la base de solvant.
The first rule that must be met when applying it is that the layers on which it is applied must be completely dry. If they are not, they may not dry properly and the microcement may not achieve its full technical performance.
Once dry, apply it to the surface with a short-haired roller, avoiding puddles. The drying time of polyurethane varnish in microcement is usually between 12 and 24 hours depending on the manufacturer. At Lunik we recommend that it be at least 12 hours but with ambient conditions of 20 degrees and low relative humidity. If the conditions are very contrary, it is recommended to extend the time.
The time between layers of polyurethane is extremely important, since although it seems dry to the touch, it is not. Chemical reactions are taking place within the layer many hours after its application. That is why, to avoid problems, it is essential to ensure a good cure of the first layer of polyurethane before applying the second. Otherwise, it could cause the layer not to harden and the end result is not what you want.
Once applied, the resulting layer does not reach its maximum strength for approximately one month later. This implies that during the first weeks, and especially the first days, extreme precautions must be taken on the microcement surface.
During the first days you should not pour water, and you have to avoid putting heavy elements. Of course, dragging objects or placing sharp objects could also damage the final coat.
At Lunik we recommend having the best materials to avoid finishing problems, or later complaints. Visit us on our Lunik website for more information.