Migration of organic molecules both into the polymer layer and out of the polymer layer through the lacquer layer presents a problem. The migration of plasticizers out of PVC leads to hardening of the PVC product and thus a change in properties (e.g. embrittlement). If the PVC coating is in direct contact with other materials such as laminated foams, the plasticizer migrates into these contact materials and changes their properties.
At FILK, lacquer with a good barrier effect for organic molecules based on polylactide (PLA) was developed. Depending on the composition of the PLA lacquer, it could be suitable for PVC or PUR artificial leather. The finish extremely retards the migration of plasticizers out of PVC synthetic leather or from colouring media into artificial leather. The PLA lacquer is solvent-based and has solids content of around 10%. Since it is a 1K system, it can be stored for a longer time. The application can take place in the usual gravure printing process with anilox rollers. The lacquer is dried at 150 °C for 3 minutes. This can be followed by embossing at temperatures of up to 155 °C.