Modern laminated chipboards are superstrong pressed laminated chipboards with high mechanic properties, which are capable of resisting any climatic, chemical and biological impacts. They are resistant to excessive humidity and ultraviolet. Due to multi-layer structure, laminated chipboards are not subject to any deformation, drying, cracking and buckling because of the temperature and humidity difference.
The lamination process can be divided into 4 technological phases or stages.
The first phase – preparation of laminated chipboards
It is worth mentioning that chipboards which meet certain technical parameters are used for lamination: thickness of at least 0.65-0.7 g/sm3 and humidity of no more than 7-8%. Such boards cannot be destroyed and do not lose their structure if they are pressed further. Suitable boards are sanded and as long as the process is over and the wood dust is removed, the surface is covered with a special filler compound.
The second phase – preparation of the laminating material
Chipboards are laminated using paper and resin laminate. This is special paper saturated with synthetic resins which has unique appearance and characteristics. The thing is that the surface of chipboards is covered not with one but at least with three laminating layers: one major layer, one seal layer and one finishing layer. Paper background has the biggest thickness and density: it ensures mechanical resistance of chipboards and protects the inner layers from humidity. The seal paper layer has a decorative function – the drawing is printed on it. The finishing paper and the lacquer film increase the wear-resisting properties of the laminated chipboard and ensure reliable protection from moisture.
The second phase of laminated chipboard production – arrangement of “packages”
A “package” is the technical name of a sheet of laminated chipboard which has been covered with laminating paper layers on both sides in the corresponding order (major, seal and finishing layers). Packages arrange in this way are laid between polished steel or brass filler sheets. This is done to make the surface of laminated chipboards smooth.
The second phase of laminated chipboard production – pressing
The stage envisages pressing chipboards and laminating paper into laminated chipboards. This is done at 135-145 °С and maximum pressure of 1.5-2 MPa, which is gradually decreased towards the end of the process to avoid any deformation of chipboards.
The process of pressing lasts for about 15 minutes: several minutes before the end of the operation the press tables are not only relaxed but also cooled by means of water. In some cases this is done to get the matted (grained) surface and reduce the time spent on one pressing cycle.
Laminated chipboards are produced using modern German lines equipped with an automated quality control system for each technological stage.