Abstract: The present invention is related to a method for the production of polyurethane foam, comprising the steps of: providing an isocyanate-reactive component A comprising a polyol component A1 which further comprises a physical blowing agent T; combining at least the isocyanate-reactive component A and an isocyanate component B, thereby obtaining a polyurethane reaction mixture; providing the polyurethane reaction mixture in a cavity (11); and reducing the pressure within the cavity (11) to a pressure lower than ambient pressure; characterized in that the cavity (11) is ventilated to ambient pressure before the gel time of the polyurethane reaction mixture is reached.

Abstract: The present invention is related to a method for the production of polyurethane foam, comprising the steps of: (1) providing an isocyanate-reactive component A comprising a polyol component A1 which further comprises a physical blowing agent T; (2) combining at least the isocyanate-reactive component A and an isocyanate component B, thereby obtaining a polyurethane reaction mixture; (3) providing the polyurethane reaction mixture in a cavity (11); and (4) reducing the pressure within the cavity (11) to a pressure lower than ambient pressure. The method is characterized in that the cavity (11) is ventilated to ambient pressure before the gel time of the polyurethane reaction mixture is reached.

Abstract: The present invention is related to a method for the production of polyurethane foam, comprising the steps of: providing an isocyanate-reactive component A comprising a polyol component A1 which comprises a physical blowing agent T; combining at least the isocyanate-reactive component A and an isocyanate component B, thereby obtaining a polyurethane reaction mixture; providing the polyurethane reaction mixture in a cavity (11); and reducing the pressure within the cavity (11) to a pressure lower than ambient pressure; characterized in that the physical blowing agent T is present in the isocyanate-reactive component A in the form of an emulsion with the polyol component A1 constituting the continuous phase and droplets of the physical blowing agent T the dispersed phase of the emulsion, wherein the average size of the droplets of the physical blowing agent T is ?0.1 ?m to ?20 ?m, the droplet size being determined by using an optical microscope operating in bright field transmission mode.

Abstract: The present invention is related to a method for the production of polyurethane foam, comprising the steps of: providing an isocyanate-reactive component A comprising a polyol component A1 which further comprises a physical blowing agent T; combining at least the isocyanate-reactive component A and an isocyanate component B, thereby obtaining a polyurethane reaction mixture; providing the polyurethane reaction mixture in a cavity (11); and reducing the pressure within the cavity (11) to a pressure lower than ambient pressure; characterized in that the cavity (11) is ventilated to ambient pressure before the gel time of the polyurethane reaction mixture is reached.