Patents Assigned to Uhde Inventa-Fischer AG
  • Patent number: 8470220
    Abstract: In the case of the method for the production of polyester granulate or molded articles from a melt which is discharged from a polycondensation (1), the melt in the discharge region (2) of the polycondensation is kept at a temperature between 270-285° C. in communication with a gas chamber at a reduced pressure in order according to the invention to achieve a low acetaldehyde content. With respect to the granulate, within the scope of the method according to the invention, a standard crystallization (5) and drying (6) with air as drying gas suffices. The molded articles can be produced directly from the melt, e.g. with an injection molding machine (9). The device according to the invention comprises a polycondensation, at least the last stage of which is configured as a disc reactor in which, with extensive avoidance of a sump, the melt is transported directly from disc to disc by a combination of rotating disc and static strippers fitted on the circumference of the reactor.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: June 25, 2013
    Assignee: UHDE Inventa-Fischer AG
    Inventors: Kurt Hanimann, Werner Stibal
  • Patent number: 7674878
    Abstract: Disclosed is a method of producing a non-adhering granulate above the glass-transition temperature comprising a polyester material, in which the polyester material is introduced into a cooling water flow as a melt and is separated from the cooling water after passing through a cooling stretch. The dwell time of the polyester material in the cooling stretch is 0.2-5 sec, and the cooling water has a pressure of at least 2 bar along the cooling stretch. For the thus obtained granulate, post-crystallization is not required, at least not in every case. It has been shown that the granulate does not adhere, even without post-crystallization and mechanical movement if no additional external input of energy takes place. Even during heating under pressure, no adhesion could be observed.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: March 9, 2010
    Assignee: Uhde Inventa-Fischer AG
    Inventors: Kurt Hanimann, Werner Stibal
  • Publication number: 20090057936
    Abstract: Disclosed is a method of producing a non-adhering granulate above the glass-transition temperature comprising a polyester material, in which the polyester material is introduced into a cooling water flow as a melt and is separated from the cooling water after passing through a cooling stretch. The dwell time of the polyester material in the cooling stretch is 0.2-5 sec, and the cooling water has a pressure of at least 2 bar along the cooling stretch. For the thus obtained granulate, post-crystallisation is not required, at least not in every case. It has been shown that the granulate does not adhere even without post-crystallisation and mechanical movement if no additional external input of energy takes place. Even during heating under pressure, no adhesion could be observed.
    Type: Application
    Filed: March 13, 2007
    Publication date: March 5, 2009
    Applicant: UHDE INVENTA-FISCHER AG
    Inventors: Kurt Hanimann, Werner Stibal