Patents Assigned to Syntec Gesellschaft fur Chemie und Technologie der Informationsaufzeichnu ng mbH
  • Patent number: 6015621
    Abstract: An ultraviolet-sensitive dosimeter material comprises at least one diazonium compound featuring absorption in the ultraviolet wavelength range, and a binder. The diazonium compound is preferably formed by a diazonium salt of the general formula ##STR1## in which R.sub.1, R.sub.2, R.sub.3 and X.sup.- are selected from the following groups:R.sub.1 : H, halogen, alkyl with C.sub.1 -C.sub.5, alkoxy with C.sub.1 -C.sub.5, aryloxy,R.sub.2 : H, halogen, alkyl with C.sub.1 -C.sub.5, alkoxy with C.sub.1 -C.sub.5, aryloxy,NR'R" (R', R" same or differing alkyl compounds or heterocyclic armines, or COOR.sub.4 (R.sub.4 alkyl with C.sub.1 -C.sub.5), andR.sub.3 : H, alkoxy with C.sub.1 -C.sub.5, andX.sup.- : diazo process anions, or perfluorinated aliphatic or aromatic anions.
    Type: Grant
    Filed: April 28, 1998
    Date of Patent: January 18, 2000
    Assignee: Syntec Gesellschaft fur Chemie und Technologie der Informationsaufzeichnu ng mbH
    Inventors: Regina Lischewski, Ursula Sell, Jorg Marx, Uwe Gohs
  • Patent number: 5786121
    Abstract: A process is for producing electrophotographically active titanylphthalocyanine. In the process, which has an improved space-time yield, titanylphthalocyanine is dissolved in pentafluoropropionic acid and a solvent of the group comprising halogenated alkanes/aromatic compounds or halogenated alkanes/aromatic compounds and sulphonic acids. The active form is precipitated by precipitation with water in the presence of a further polar organic solvent. A mixture of pentafluoropropionic acid and methylene chloride and a mixture of p-toluene sulphonic acid and methane sulphonic acid are particularly suitable as solvents. The precipitated product processes very good electrophotographic properties.
    Type: Grant
    Filed: July 15, 1997
    Date of Patent: July 28, 1998
    Assignee: Syntec Gesellschaft fur Chemie und Technologie der Informationsaufzeichnu ng mbH
    Inventors: Andreas M. Richter, Roland Ackermann, Manfred Lutz, Hans-Josef Humpert