Patents by Inventor Gerardus J. Crommentuyn

Gerardus J. Crommentuyn 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).

  • Patent number: 5296327
    Abstract: A toner powder for the development of latent electrostatic or magnetic images, the toner powder containing a polyester resin based on an etherified diphenol and a dicarboxylic acid mixed with a reaction product of an epoxy resin and a phenol compound or a carboxylic acid, and the process for forming fixed images on an image receiving material utilizing the above toner powder, the surface of an intermediate medium consisting of material having a lower affinity for the softened toner powder than does the image receiving material and the toner powder being softened by heating before and/or during transit through a pressure zone.
    Type: Grant
    Filed: March 13, 1992
    Date of Patent: March 22, 1994
    Assignee: Oce-Nederland B.V.
    Inventors: Marcel L. M. Pennings, Rudolf A. M. Venderbosch, Wilhelmus H. G. Albrink, Gerardus J. Crommentuyn
  • Patent number: 4443527
    Abstract: Colored magnetically attractable toner powder for the development of latent electrostatic or magnetic images consists of particles each comprising a magnetically attractable core, preferably spherical, formed of particulate magnetically attractable material or of a dispersion of such material in a binder, a masking layer enveloping the core and containing binder mixed with light-reflecting pigment of submicron particle size, and coloring material applied in and/or onto the masking layer. Processes for preparing the toner powder are disclosed, and a process for developing electrostatic or magnetic latent image patterns by its use.
    Type: Grant
    Filed: September 2, 1982
    Date of Patent: April 17, 1984
    Assignee: Oce-Nederland B.V.
    Inventors: Harm H. Heikens, Gerardus J. Crommentuyn
  • Patent number: 4286037
    Abstract: Electrically conductive developer powder for developing electrostatic images by inductive attraction is provided, with avoidance of practical disadvantages of known "one-component" developer powders, by incorporating finely divided water-insoluble quaternary ammonium salt into thermoplastic resin particles forming the powder, with or without other finely divided additives such as coloring material and/or magnetically attractable material. The specific resistance of the resin particles is lowered to between 10.sup.7 and 10.sup.11 ohm. cm by from 8 to 35% by weight of the quaternary ammonium salt, and can be lowered further by additions of fine conductive material such as carbon black. The resin particles remain sufficiently fusible even when they also contain enough magnetically attractable material, e.g. about 50% by weight, to render them transportable by a magnetic powder-applicator.
    Type: Grant
    Filed: September 5, 1978
    Date of Patent: August 25, 1981
    Assignee: Oce-van der Grinten N.V.
    Inventors: Adrianus M. P. Hectors, Gerardus J. Crommentuyn
  • Patent number: 4146494
    Abstract: Electrically conductive developer powder for developing electrostatic images by inductive attraction is provided, with avoidance of practical disadvantages of known "one-component" developer powders, by incorporating finely divided water-insoluble quaternary ammonium salt into thermoplastic resin particles forming the powder, with or without other finely divided additives such as coloring material and/or magnetically attractable material. The specific resistance of the resin particles is lowered to between 10.sup.7 and 10.sup.11 ohm. cm by from 8 to 35% by weight of the quaternary ammonium salt, and can be lowered further by additions of fine conductive material such as carbon black. The resin particles remain sufficiently fusible even when they also contain enough magnetically attractable material, e.g. about 50% by weight, to render them transportable by a magnetic powder-applicator.
    Type: Grant
    Filed: January 7, 1977
    Date of Patent: March 27, 1979
    Assignee: Oce-van de Grinten N.V.
    Inventors: Adrianus M. P. Hectors, Gerardus J. Crommentuyn
  • Patent number: 3991128
    Abstract: Vinylpyrene (substituted or not) is prepared in a single reaction stage by reacting the corresponding acetylpyrene with a metal alkoxide, e.g. aluminum isopropoxide, in an inert organic solvent, e.g. a xylene, at a temperature above 110.degree. C. which, for some reaction conditions, optimally is between 130.degree. and 150.degree. C. The presence of hydroquinone in the mixture reduces the time and increases the yield of the reaction.
    Type: Grant
    Filed: September 26, 1975
    Date of Patent: November 9, 1976
    Assignee: Oce-van der Grinten N.V.
    Inventors: Johanna L. E. Kortenoeven-van den Beuken, Gerardus J. Crommentuyn
  • Patent number: 3935009
    Abstract: Reproduction elements coated with organic photoconductors are made with improved and/or more widely selectable electrophotographic properties by employing in the photoconductive coating a donor-acceptor complex composed of a known organic electron donor having photo- or semiconductor properties, e.g. a poly-N-vinylcarbazole or polyvinylpyrene, and a N-(fluoren-9-ylidene)-aniline compound as an activating electron acceptor. Especially effective as the electron acceptor are certain new compounds, namely, p- and m-nitro-N-(2,4,7-trinitrofluoren-9-ylidene)-aniline and p-methylsulfonyl-N-(2,4,7-trinitrofluoren-9-ylidene)-aniline.
    Type: Grant
    Filed: February 6, 1974
    Date of Patent: January 27, 1976
    Assignee: Oce-van der Grinten N.V.
    Inventors: Gerardus J. Crommentuyn, Johannes H. A. Kuiper