WorléeCryl VP 7440 is an acrylic binder for clear coats which exhibits good blocking resistance even at elevated temperatures above 50 °C (1Kg/cm³, 24h drying at RT, 24h load). In addition, the binder achieves a very high final pendulum hardness of about 125 s despite the low minimum film formation temperature of 14 °C due to the built-in self-crosslinking mechanism. In addition, the crosslinking leads to very good chemical resistance, so that it can be used in the furniture sector. The WorléeCryl VP 7440 is particularly convincing due to its high ethanol resistance of several hours.
This is even better than that of WorléeCryl 7410, which is somewhat more resistant to chemicals and harder than WorléeCryl 7440, but requires a higher amount of film-forming agent and does not reach the very high blocking resistance of WorléeCryl VP 7440. The finely divided dispersion of pure acrylate also provides a special property: the films produced with a 100μm splitting blade have a remarkably high wet transparency. Development has shown that it is not only the particle size that is decisive for this property, although wet transparency with a high particle size is not possible, but also the selection of emulsifiers plays a decisive role. The binder is suitable for spray application and shows a very high drying speed, naturally depending on the solvent selection. Thus, for a sample mixed with butyl glycol, a drying degree of 6 according to Erichsen could be achieved after only half an hour (at 50 % relative humidity and 20 °C).
Worlée’s application technology laboratory in Lübeck is currently working on a pigmented starting formulation. The first challenge, strong foam formation during dispersion, has already been overcome by using WorléeAdd 6223 in the ground material.