Page 23 - Parquet International december 2014

ing), thereby shortening finishing times enormously. Many products by now have el- evated UV radiation stability, excellent im- pact strength, optimum hardness, and good chemical resistance. These products are ap- plied liquid using a pre-heater and then so- lidify at room temperature. These short nar- row strips require three or four days of stor- age before they can be profiled, however.
The world of varnish
For those who use traditional processes, water-based varnishes – the only ones with respect for the envi-
ronment – have been
available in the market for quite some time now, even if they have often been overshad- owed by solvent-based products that are easi- er to sell. Painting sys- tems are designed on the basis of the type of paint and finish de- sired by parquet pro- ducers while also bear- ing in mind the possi- bility for light or heavy staining.
Despite the fact that application and dry- ing systems and cycles vary widely, there are also versatile polyva- lent machines capable of being quickly and easily set up for the desired type of finish. One multilayer par- quet element varnish- ing process that is be- ing adopted all around the world utilizes three coats of primer ap- plied by roller, each of 10 g/sq m thickness. The process consists of an intermediate semi-polymerization, a final polymerization with a subsequent in- termediate sanding followed by two fin- ishing coats applied by roller of 10 g/sq m each, with an interme- diate semi-polymer- ization and a final UV polymerization. The system can have min- imum widths of 30 cm.
and the machines used include: lacquering machine with standard rollers (provided with applicator roller and dosing roller with three separate commands that permit the dosing roller to rotate in opposite direction whenever minimum applications are re- quired), UV-module driers (that polymerize varnishing products in just a few seconds, to which photoinitiators are added) and inter- mediate sanding machines (used to smoothen the surface with primer and pre- pare it for the application of the finish).
The technology behind UV paint products R