Patents by Inventor Hans Lichtenstein

Hans Lichtenstein 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).

  • Publication number: 20130074930
    Abstract: The invention relates to a combination of fluorescence conversion dyes in plastics mouldings made of polymethyl (meth)acrylate, where these are used to convert natural insolation into light that can be used by the solar cells.
    Type: Application
    Filed: July 5, 2011
    Publication date: March 28, 2013
    Applicant: Evonik Roehm GmbH
    Inventors: Hans Lichtenstein, Claudius Neumann
  • Publication number: 20090146548
    Abstract: The invention relates to an apparatus for illumination with blue, green, yellow or red light-emitting diodes (LEDS), comprising one or more coloured LEDs and a light-scattering cover associated with the LED colour and composed of coloured plastic and having a base colour derived from one or more non-fluorescent dyes, characterized in that the light-scattering cover comprises, in addition to the base colour, at least one fluorescent dye associated in terms of colour with the base colour, where the dye mixture has been adjusted in such a way that the reflectance of the light-scattering cover is at least 28% at the wavelength of the energy maximum of the LED(S) used, where, based on the standard chromaticity diagram and on the colour loci of the reflected light from the light-scattering cover and on the colour locus of the LED(s) used, the following alternative relationship applies to the absolute value of the difference between the x value of the light-scattering cover and the x value of the LED and the absolut
    Type: Application
    Filed: November 9, 2006
    Publication date: June 11, 2009
    Applicant: EVONIK ROEHM GMBH
    Inventors: Hans Lichtenstein, Damrien Machert
  • Patent number: 7497972
    Abstract: The invention relates to a moulding composed of a plastics matrix composed of a transparent plastic, comprising a soluble fluorescent dye and a scattering agent whose refractive-index difference from the plastics matrix is +/? from 0.003 to 0.2, characterized in that a white pigment whose refractive-index difference from the plastics matrix is from +0.4 to 1.5 is also present, at a concentration of from 0.001 to 0.1% by weight.
    Type: Grant
    Filed: July 25, 2003
    Date of Patent: March 3, 2009
    Assignee: Roehm GmbH & Co. KG
    Inventors: Hans Lichtenstein, Guenther Ittmann, Eduard Albrecht
  • Publication number: 20070161744
    Abstract: The invention relates to a polymer solvent binding agent for pigments based on methylmethacrylate. The binding agent is a polymer made of methylmethacrylate and one or several additional radical polymerisierable compounds and is used in the form of a partially polymerised sirup.
    Type: Application
    Filed: January 14, 2005
    Publication date: July 12, 2007
    Applicant: ROEHM GBMH & CO., KG
    Inventors: Klaus Kabs, Frank Schafer, Hans Lichtenstein, Bernd Klossek
  • Publication number: 20060229397
    Abstract: The invention relates to moulded bodies for illuminated advertising, comprising a poly(meth)acrylate matrix, diffusion particles containing plastic and inorganic diffusion particles. Said moulded bodies contain between 0.05 and 0.5 wt. % diffusion particles containing plastic with a size ranging between 5 and 15 ?m and between 0.1 and 3 wt. % inorganic diffusion particles with a size ranging between 1 and 7.5 ?m.
    Type: Application
    Filed: March 2, 2004
    Publication date: October 12, 2006
    Applicant: Roehm GMBH & Co. KG
    Inventors: Hans Lichtenstein, Guenther Ittmann
  • Patent number: 7052161
    Abstract: The invention relates to an illuminative device essentionaly comprising a light source and a diffusing cover which is assigned to the light source and is made of colored plastic. The light source consites of one or several light-emitting diodes (LEDs) emitting a colored an substantially monocromatic light. The diffusing cover assigned thereto has a transmition (DIN 5036) of at least 35% and a reflection (DIN 5036) of at least 15% with the wavelength of the light-emitting diode operating at relative maximum energy.
    Type: Grant
    Filed: November 21, 2002
    Date of Patent: May 30, 2006
    Assignee: ROEHM GmbH & Co. KG
    Inventors: Hans Lichtenstein, Jann Schmidt, Guenther Ittmann, Eduard Albrecht
  • Patent number: 7046903
    Abstract: The present invention relates to a light-guide body, which has at least one light-entry surface and at least one light-exit surface, the ratio of the light-exit surface area to the light-entry surface area being at least 4, comprising at least one light-guiding layer with a thickness of at least 2 mm, characterized in that the light-guiding layer comprises at least 60% by weight, expressed in terms of the weight of the light-guiding layer, of polymethyl methacrylate and from 0.001 to 0.08% by weight, expressed in terms of the weight of the light-guiding layer, of spherical barium sulphate particles with an average diameter in the range of from 0.3 to 20 ?m.
    Type: Grant
    Filed: October 16, 2002
    Date of Patent: May 16, 2006
    Assignee: Roehm GmbH & Co. KG
    Inventors: Jann Schmidt, Guenther Ittmann, Hans Lichtenstein, Herbert Groothues
  • Publication number: 20050288416
    Abstract: The invention relates to a moulding composed of a plastics matrix composed of a transparent plastic, comprising a soluble fluorescent dye and a scattering agent whose refractive-index difference from the plastics matrix is +/? from 0.003 to 0.2, characterized in that a white pigment whose refractive-index difference from the plastics matrix is from +0.4 to 1.5 is also present, at a concentration of from 0.001 to 0.1% by weight.
    Type: Application
    Filed: July 25, 2003
    Publication date: December 29, 2005
    Applicant: ROEHM GmbH & Co., KG
    Inventors: Hans Lichtenstein, Guenther Ittmann, Eduard Albrecht
  • Publication number: 20050002189
    Abstract: An illuminative device including a light source and a diffusing cover assigned to the light source and of colored plastic. The light source includes one or plural light-emitting diodes (LEDs) emitting a colored and substantially monochromatic light. The diffusing cover has a transmission of at least 35% (measured according to DIN 5036) and a reflection of at least 15% (measured according to DIN 5036) with the wavelength of the light-emitting diode operating at relative maximum energy.
    Type: Application
    Filed: November 21, 2002
    Publication date: January 6, 2005
    Inventors: Hans Lichtenstein, Jann Schmidt, Guenther Ittmann, Eduard Albrecht
  • Publication number: 20040264159
    Abstract: The present invention relates to a light-guide body, which has at least one light-entry surface and at least one light-exit surface, the ratio of the light-exit surface area to the light-entry surface area being at least 4, comprising at least one light-guiding layer with a thickness of at least 2 mm, characterized in that the light-guiding layer comprises at least 60% by weight, expressed in terms of the weight of the light-guiding layer, of polymethyl methacrylate and from 0.001 to 0.08% by weight, expressed in terms of the weight of the light-guiding layer, of spherical barium sulphate particles with an average diameter in the range of from 0.3 to 20 &mgr;m.
    Type: Application
    Filed: March 11, 2004
    Publication date: December 30, 2004
    Inventors: Jann Schmidt, Guenther Ittmann, Hans Lichtenstein, Herbert Groothues
  • Patent number: 5621028
    Abstract: The invention relates to light-scattering polymethacrylate resins with high heat- and weather resistance, which resins may optionally be colored with dyestuffs or pigments. The desirable properties are achieved by addition of a combination of:particles which are light-scattering, and are crosslinked and contain phenyl groups;UV protectants; andradical scavengers.The inventive polymethacrylate molded articles are advantageously employed in illumination technology.
    Type: Grant
    Filed: March 3, 1994
    Date of Patent: April 15, 1997
    Assignee: Roehm GmbH Chemische Fabrik
    Inventors: Hans Lichtenstein, Silvia Ebert
  • Patent number: 5449727
    Abstract: Color concentrates comprising a colorant such as a pigment and a polymeric binder, and polymeric binders therefor, said polymeric binders comprising:(a) 70-90 percent of methyl methacrylate, by weight of the polymer;(b) 10-20 percent of methyl acrylate; and(c) from 0 to 10 percent of at least one free radically polymerizable monomer of the formula ##STR1## wherein R.sub.1 is hydrogen or methyl and R.sub.2 is a moiety carrying a functional group.
    Type: Grant
    Filed: September 1, 1993
    Date of Patent: September 12, 1995
    Assignee: Rohm GmbH
    Inventors: Manfred Krieg, Hans Lichtenstein, Ludwig Hosch, Guenther Ittmann
  • Patent number: 5387634
    Abstract: Opaque tinted acrylic glass produced with organic pigments or with organic dyes, which in addition to the colorant, also contains an acid in the polymer matrix, exhibits improved resistance to weathering.
    Type: Grant
    Filed: January 15, 1993
    Date of Patent: February 7, 1995
    Assignee: Roehm GmbH Chemische Fabrik
    Inventors: Hans Lichtenstein, Silvia Ebert, Manfred Krieg
  • Patent number: 4957987
    Abstract: Color concentrates comprising a colorant such as a pigment and a polymeric binder and polymeric binders therefor, said polymeric binders comprising:(a) 70-90 percent of methyl methacrylate, by weight of the polymer;(b) 10-20 percent of methyl acrylate; and(c) from 0 to 10 percent of at least one free radically polymerizable monomer of the formula ##STR1## wherein R.sub.1 is hydrogen or methyl and R.sub.2 is a moiety carrying a functonal group.
    Type: Grant
    Filed: April 25, 1988
    Date of Patent: September 18, 1990
    Assignee: Rohym GmbH
    Inventors: Manfred Krieg, Hans Lichtenstein, Ludwig Hosch, Guenther Ittmann
  • Patent number: 4773913
    Abstract: Color concentrates comprising a colorant such as a pigment and a polymeric binder, and polymeric binders therefor, said polymeric binders comprising:(a) 70-90 percent of methyl methacrylate, by weight of the polymer;(b) 10-20 percent of methyl acrylate; and(c) from 0 to 10 percent of at least one free radically polymerizable monomer of the formula ##STR1## wherein R.sub.1 is hydrogen or methyl and R.sub.2 is a moiety carrying a functional group.
    Type: Grant
    Filed: January 2, 1987
    Date of Patent: September 27, 1988
    Assignee: Rohm GmbH
    Inventors: Manfred Krieg, Hans Lichtenstein, Ludwig Hosch, Guenther Ittmann