Patents by Inventor Klaus Dieter Schomann

Klaus Dieter Schomann has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Carbonyloxy-substituted azulenesquaric acid dyes, intermediates therefor and optical recording medium
    Patent number: 5728867
    Abstract: Carbonyloxy-substituted azulenesquaric acid dyes of the formula ##STR1## where L is C.sub.1 -C.sub.12 -alkylene which may be substituted by phenyl,R.sup.1 is C.sub.1 -C.sub.12 -alkyl, monounsaturated or polyunsaturated C.sub.3 -C.sub.12 -alkenyl, which may be phenyl-substituted, C.sub.3 -C.sub.7 -cycloalkyl, C.sub.3 -C.sub.7 -cycloalkenyl, substituted or unsubstituted phenyl, pyrrolyl, furanyl, thienyl or pyridyl andR.sup.2, R.sup.3, R.sup.4 and R.sup.5 are each independently of the others hydrogen or substituted or unsubstituted C.sub.1 -C.sub.12 -alkyl,with the proviso that when R.sup.3 is hydrogen the positions of the substituents CH.sub.2 --L--O--CO--R.sup.1 and R.sup.4 on either or both azulene rings may also be interchanged with each other within an azulene ring, are useful in an optical recording medium.
    Type: Grant
    Filed: October 25, 1990
    Date of Patent: March 17, 1998
    Assignee: BASF Aktiengesellschaft
    Inventors: Michael Schmitt, Wolfgang Schrott, Peter Neumann, Sibylle Brosius, Klaus Dieter Schomann, Harald Kuppelmaier
  • Naphtholactamtrimethine dyes and optical recording medium containing same
    Patent number: 5002863
    Abstract: Naphtholactamtrimethine dyes useful in optical recording media have the formula ##STR1## where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are identical or different and each is independently of the others C.sub.1 -C.sub.22 -alkyl, which may be substituted and/or interrupted by one or more oxygen atoms, one or more imino groups or one or more C.sub.1 -C.sub.4 -alkylimino groups, or is substituted or unsubstituted C.sub.5 -C.sub.7 -cycloalkyl or substituted or unsubstituted phenyl, and the rings A, B, C and D may each be substituted and/or benzofused.
    Type: Grant
    Filed: November 17, 1988
    Date of Patent: March 26, 1991
    Assignee: BASF Aktiengesellschaft
    Inventors: Matthias Dust, Peter Neumann, Michael Acker, Heidi Benthack-Thoms, Klaus-Dieter Schomann, Harald Kuppelmaier
  • Naphtholactam dyes and optical recording medium containing these dyes
    Patent number: 4939012
    Abstract: Naphtholactam dyes of the formula ##STR1## where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, n, p, Z.sup.1, Z.sup.2 and the rings A, B, C and D each have the meanings stated in the description, and an optical recording medium which contains one or more naphtholactam dyes and may contain a base.
    Type: Grant
    Filed: August 21, 1989
    Date of Patent: July 3, 1990
    Assignee: BASF Aktiengesellschaft
    Inventors: Matthias Dust, Peter Neumann, Ernst Schefczik, Heidi Benthack-Thoms, Helmut Barzynski, Klaus-Dieter Schomann, Harald Kupplemaier, Eberhard Koester
  • Naphtholactam dyes and optical recording medium containing these days
    Patent number: 4876356
    Abstract: Naphtholactam dyes of the formula ##STR1## where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, n, p, Z.sup.1, Z.sup.2 and the rings A, B, C and D each have the meanings stated in the description, and an optical recording medium which contains one or more naphtholactam dyes and may contain a base.
    Type: Grant
    Filed: March 12, 1987
    Date of Patent: October 24, 1989
    Assignee: BASF Aktiengesellschaft
    Inventors: Matthias Dust, Peter Neumann, Ernst Schefczik, Heidi Benthack-Thoms, Helmut Barzynski, Klaus-Dieter Schomann, Harald Kuppelmaier, Eberhard Koester
  • Novel tetraphenyldithiolene complexes, asymmetrically substituted benzoins, and optical recording materials containing the novel complexes
    Patent number: 4806664
    Abstract: Tetraphenyldithiolene complexes of the formula ##STR1## and novel asymmetrically substituted benzoins of the formula ##STR2## where X.sup.1, X.sup.2 and X have the meanings stated in the description and Me is nickel, palladium or platinum. The complexes have very high absorption in the range from 800 to 950 nm and are readily soluble in the plastics used for the production of optical recording materials.The recording materials produced using these complexes have a very high signal/noise ratio.
    Type: Grant
    Filed: June 8, 1987
    Date of Patent: February 21, 1989
    Assignee: BASF Aktiengesellschaft
    Inventors: Wolfgang Schrott, Peter Neumann, Bernhard Albert, Michael Thomas, Helmut Barzynski, Klaus-Dieter Schomann, Harald Kuppelmaier
  • Guide system and magnetic tape cassette comprising such a system
    Patent number: 4625252
    Abstract: A tape guide system, especially a tape guide system for a magnetic tape cassette, comprising conductive connecting means between the tape guide elements and/or the front and back of the tape, prevents the tape from blocking, slipping from the tape reels, or folding over. In practical embodiments, pieces of flexible conductive plastics film are arranged in the vicinity of the guide elements. The novel tape guide system can be used in any type of magnetic tape transport mechanism in which increased friction occurs when the tape is transported, especially in video cassettes for all systems.
    Type: Grant
    Filed: August 25, 1982
    Date of Patent: November 25, 1986
    Assignee: BASF Aktiengesellschaft
    Inventors: Werner Balz, Wulf Muenzner, Klaus Dieter Schomann, Heinz Berger, Roland Roos