Verfahren zur Herstellung von Dichtungen fuer Flaschenverschluesse und Vorrichtung zur Durchfuehrung des Verfahrens

摘要

A gasket is prepared in a bottle cap by reacting in the bottle cap a first component containing a polyol having 2 or 3 hydroxyl functional groups in one molecule and a second component containing a polymethylene polyphenylisocyanate, preferably a quasi-prepolymer of a polymethylene polyphenylisocyanate having an isocyanate equivalent of not more than 300 until a cured substantially non-porous polyurethane gasket is obtained. The thus obtained seaing gasket undergoes neither deformation, color change nor weight loss over a prolonged period of time and has no tackiness on its surface.