Patents by Inventor Piet Kok

Piet Kok 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: 5939278
    Abstract: A semi-automated method of classifying a histological specimen for the presence of premalignant or malignant cells, including the steps of treating a specimen with an immunohistochemical marker to provide a visual indication of cell proliferation, ranking individual objects in the specimen in an order according to the likelihood that each object has attributes consistent with a premalignant or malignant cell or cell cluster, selecting for display a set of said objects according to said ranking, and displaying images of said selected objects to facilitate review by an operator.
    Type: Grant
    Filed: August 12, 1996
    Date of Patent: August 17, 1999
    Assignee: Neuromedical Systems, Inc.
    Inventors: Mathilde Elisabeth Boon, Lanbrecht Piet Kok, Laurie J. Mango, Akiva Rutenberg, Mark R. Rutenberg
  • Patent number: 5536817
    Abstract: A modified gelatin is disclosed wherein part of the free carboxyl groups is replaced by modifiers having more acid end-standing groups chosen from --SO.sub.3 M, --OSO.sub.3 M, --SSO.sub.3 M, ---OPO(OH).sub.2, --OPO(OH)(OR.sup.2), --PO(OH).sub.2, --PO(OH)(OR.sup.2).In a preferred embodiment such a modified gelatin is incorporated in a DTR photographic material which after processing can serve as a lithographic printing plate. Thanks to the more hydrophilic character of the modified gelatin the differentiation between printing and non-printing areas is improved and toning at printing start-up is reduced.
    Type: Grant
    Filed: August 30, 1995
    Date of Patent: July 16, 1996
    Assignee: AGFA-GEVAERT, N.V.
    Inventors: Eddy Michiels, Piet Kok, Johan Loccufier, Frank Michiels, Ludo Van Rompuy
  • Patent number: 5474885
    Abstract: A modified gelatin is disclosed wherein part of the free carboxyl groups is replaced by modifiers having more acid end-standing groups chosen from --SO.sub.3 M, --OSO.sub.3 M, --SSO.sub.3 M, --OPO(OH).sub.2, --OPO(OH)(OR.sup.2), --PO(OH).sub.2, --PO(OH)(OR.sup.2).In a preferred embodiment such a modified gelatin is incorporated in a DTR photographic material which after processing can serve as a lithographic printing plate. Thanks to the more hydrophilic character of the modified gelatin the differentiation between printing and non-printing areas is improved and toning at printing start-up is reduced.
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: December 12, 1995
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Eddy Michiels, Piet Kok, Johan Loccufier, Frank Michiels, Ludo Van Rompuy
  • Patent number: 5439791
    Abstract: New types of modified gelatins are disclosed, modified at part of the free carboxyl groups of the polypeptide chain, by the introduction of a new end-standing amino, sulphinic acid or thiol group. The modified gelatins show an enhanced reactivity towards vinylsulphonyl hardeners. The invention further includes hardened modified gelatin types and hydrophilic elements containing them. In particular, a differentially hardened multilayer element, preferably a photographic element, is disclosed.
    Type: Grant
    Filed: February 10, 1994
    Date of Patent: August 8, 1995
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Piet Kok, Jean-Marie Dewanckele, Johan Loccufier, Eddy Michiels, Frank Michiels
  • Patent number: 5254443
    Abstract: A photographic direct positive material is disclosed comprising a support and one or more radiation sensitive emulsion layers containing internal latent image-forming silver halide grains characterized in that at least one of said emulsion layers further contains a masked stabilizer corresponding to general formula (I): ##STR1## wherein Z represents a lower alkyl group, a nitro group or a halogen atom, n=0 to 4, and M represents a positive counterion.Preferred compounds are 1-(2-sulphonatobenzoyl)-5-methyl-benzotriazole, 1-(2-sulphonatobenzoyl)-6-methyl-benzotriazole or a mixture of both.The masked stabilizer is preferably incorporated in the emulsion layer(s). The material preferably further contains a nucleating agent. Improved direct positive sensitometric properties and wider exposure latitude before encountering rereversal are obtained.
    Type: Grant
    Filed: July 21, 1992
    Date of Patent: October 19, 1993
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Piet Kok, Jean-Marie O. Dewanckele
  • Patent number: 5236815
    Abstract: A new class of photographic masked stabilizers is disclosed showing following general chemical formula (Ia) or (Ib): ##STR1## wherein X and Y each independently represent N or CR, R being hydrogen or lower alkyl,Z represents a lower alkyl group, a nitro group, a halogen atom or hydrogen, andM represents a positive counterion, preferably an alkali cation, ammonium or substituted ammonium.The compounds are demasked by hydrolysis under alkaline conditions. They can be incorporated in a developing solution or in a photographic material, preferably in the backing layer. They show an enhanced solvability in water compared to the corresponding unmasked stabilizers.A preferred compound is 1-(2-sulphonatobenzoyl)-5-nitroindazole trimethylamine, sodium or potassium salt.
    Type: Grant
    Filed: August 3, 1992
    Date of Patent: August 17, 1993
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Jean-Marie O. Dewanckele, Richard A. Ooms, Marc B. Graindourze, Piet Kok
  • Patent number: 5206123
    Abstract: A method for high contrast development of an image-wise exposed photographic element comprising a support and at least one silver halide emulsion layer, which method comprises contacting said exposed element in the presence of a hydrazine compound with an aqueous alkaline developing solution which has a pH between 10 and 13 and contains a dihydroxybenzene developing agent a 3-pyrazolidinone or an aminophenol developing agent sulphite ions and a contrast promoting amount of an amino compound characterized in that said developing solution further contains an aprotic solvent corresponding to general formula (I) or (II) : ##STR1## wherein R.sub.1 represents alkyl, substituted alkyl, alkylamino or substituted alkylamino, andR.sub.2 and R.sub.3 each independently represent alkyl substituted alkyl orwherein R.sub.1 together with R.sub.2 represent the necessary atoms to form together with the carbon and the nitrogen atom respectively to which they are attached, a heterocyclic ring, and R.sub.
    Type: Grant
    Filed: February 18, 1992
    Date of Patent: April 27, 1993
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Richard A. Ooms, Piet Kok
  • Patent number: 5156940
    Abstract: A new class of photographic stabilizers is prepared and their use in photographic materials is disclosed. These compounds are 1-phenyl-3-pyrazolidinone derivatives corresponding to following general formula: ##STR1## wherein: A represents a group capable of adsorbing at the surface of silver halides;L is a divalent linking group and r is 0 or 1;R1 and R2 each represent hydrogen, lower alkyl or substituted lower alkyl.The photographic materials containing the substances of the invention are preferably DTR mono-sheet elements which after processing can serve as planographic printing plates.
    Type: Grant
    Filed: February 13, 1991
    Date of Patent: October 20, 1992
    Assignee: AGFA-Gevaert, N.V.
    Inventors: Piet Kok, Jos A. Vaes, Jean-Marie O. Dewanckele, Luc J. Wabbes
  • Patent number: 5155014
    Abstract: Method for the production of direct-positive images by image-wise exposing a light-sensitive silver halide material comprising a support and an internal latent image-type silver halide emulsion layer and developing said exposed material in the presence of at least one development nucleator and density-increasing amounts of a compound chosen from the class consisting of formic acid, oxalic acid, glyoxylic acid, or salts of these and/or of a compound chosen from the class consisting of polyethylene glycols, with a hydroquinone-type developing solution having a pH not higher than 12.0 and comprising less than 25 g per liter of a hydroquinone and 5 to 100 g per liter of at least one alkanolamine.
    Type: Grant
    Filed: August 14, 1991
    Date of Patent: October 13, 1992
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Jozef P. De Prijcker, Fernand I. Ketels, Jean-Marie O. Dewanckele, Piet Kok
  • Patent number: 5141843
    Abstract: A developer liquid suited for use in development of photographic silver halide emulsion layer materials which liquid contains:1) hydroquinone or a substituted hydroquinone as sole developing agent or said hydroquinone as main developing agent in combination with an auxiliary developing agent in an amount less than 10 mole % with respect to the main developing agent,2) an inorganic compound yielding free sulphite ions in an amount of at least 5 grams per liter,3) an organic anti-fogging agent corresponding to the following general formula (Z): ##STR1## wherein: X.sup.2 represents an alkyl group or an aryl group including said groups in substituted form or an amino group including said group in substituted form;the amount of anti-fogging agent being in the range of 50 mg to 1 g per liter,4) a polymer containing a plurality of alkylene oxide units, and5) the necessary alkaline material to have in said liquid a pH of at least 10.5. Optional additives can also be present in the developing liquid.
    Type: Grant
    Filed: March 27, 1991
    Date of Patent: August 25, 1992
    Assignee: AGFA-Gevaert N. V.
    Inventors: Richard A. Ooms, Piet Kok, Jean-Marie O. Dewanckele
  • Patent number: 5073480
    Abstract: Process for hardening proteinaceous materials by means of a quick acting hardener corresponding to the following formula ##STR1## wherein: Z.sub.1 and Z.sub.2 each independently represent substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, or Z.sub.1 represents substituted or unsubstituted alkylidene or Z.sub.1 and Z.sub.
    Type: Grant
    Filed: July 11, 1990
    Date of Patent: December 17, 1991
    Assignee: AGFA-Gevaert, N.V.
    Inventors: Piet Kok, Erik V. Van der Eycken
  • Patent number: 5043245
    Abstract: Process for the production of a laminated article including a sheet support bearing a silver image produced by the silver complex diffusion transfer process in a layer containing developement nuclei, wherein such supported image is heat-laminated with a protective thermoplastic resin layer of sheet that covers it. The heat-lamination of the nuclei-containing layer with the silver image therein takes place in the presence of at least one of certain heterocyclic black-toning agents which are effective to prevent degradation of the neutral black coloration and density loss of the silver image as a result of heat-lamination.
    Type: Grant
    Filed: January 25, 1990
    Date of Patent: August 27, 1991
    Assignee: AGFA Gevaert, N.V.
    Inventors: Leon L. Vermeulen, Robert S. Pauwels, Piet Kok, Jean-Marie O. Dewanckele
  • Patent number: 5013628
    Abstract: Particulate toner material for use in the development of latent electrostatic images, wherein said particulate toner material is capable of acquiring by triboelectric contact electrification when in admixture with carrier particles a net positive charge and contains at least one thermoplastic resin as binder in combination with a colorant and a colorless compound capable of imparting a positive charge to the particulate toner material when in frictional contact with said carrier particles, characterized in that said colorless compound contains in it molecular structure at least one polyalkyl substituted piperidine group and a sterically hindered phenol group.
    Type: Grant
    Filed: February 5, 1990
    Date of Patent: May 7, 1991
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Piet Kok, Luc J. Vanmaele, Serge M. Tavernier, Hedwig E. De Deyne
  • Patent number: 4988600
    Abstract: Particulate toner material for use in the development of latent electrostatic images, wherein said particulate toner material is capable of acquiring by triboelectric contact electrification a net positive charge and contains thermoplastic resin(s) as binder in combination with a colorant and a colorless compound capable of imparting a positive charge to the particulate toner material in contact electrification, wherein said colorless compound contains at least one piperidine nucleus substituted with an --NH-acyl group, N-substituted ureido or N-substituted thioureido group.
    Type: Grant
    Filed: March 13, 1990
    Date of Patent: January 29, 1991
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Piet Kok, Luc J. Vanmaele, Serge M. Tavernier
  • Patent number: 4908286
    Abstract: Image-receiving material for use in diffusion transfer reversal processing comprising a polyvinyl chloride resin support coated with a hydrophilic waterpermeable layer comprising a proteinaceous colloid and a water-dispersible ionogenic polyester-polyurethane wherein isocyanate groups still present in its structure have reacted with an ionogenic compound containing at least one active hydrogen atom and a carboxylate or sulphonate salt group. This material is useful for the production of tamper proof laminates for identification purposes.
    Type: Grant
    Filed: May 3, 1989
    Date of Patent: March 13, 1990
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Ludovicus H. Vervloet, Willy P. De Smedt, Leon L. Vermeulen, Piet Kok
  • Patent number: 4902593
    Abstract: An image-receiving material suitable for image production by dye diffusion transfer processing controlled by the development of (an) image-wise exposed silver halide emulsion layer(s), wherein said image-receiving material contains a hydrophobic resin support coated with a subbing layer that is coated with an image-receiving layer containing gelatin in combination with a cationic polymeric mordant containing glycidyl groups that can react with active hydrogen atoms of gelatin, the weight ratio of said polymeric mordant to gelatin being 25:1 to 1:1 and the gelatin being present at a coverage of at least 0.1 g per m2, and wherein said subbing layer has been applied from an aqueous composition comprising a polyester-polyurethane wherein isocyanate groups still present in its structure have reacted with an ionomeric compound containing at least one active hydrogen atom and a carboxylate or sulphonate salt group.
    Type: Grant
    Filed: September 13, 1988
    Date of Patent: February 20, 1990
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Leon L. Vermeulen, Ludovicus H. Vervloet, Willy P. De Smedt, Piet Kok
  • Patent number: 4820608
    Abstract: The present invention provides a dye diffusion transfer imaging process comprising transferring image-wise by diffusion an acid dye to an image-receiving layer incorporating a non-polymeric phosphonium mordanting agent and a copolymer latex comprising free weak acid groups as a stabilizer for the mordanting agent, wherein the image-wise transfer of said acid dye is performed in the presence of a heterocyclic compound corresponding to one of the following general formulae I, II, and III: ##STR1## wherein: Y represents the non-metallic atoms needed to complete a saturated or unsaturated 5- or 6-membered heterocyclic nucleus, which may carry a fused-on aromatic ring system, and M represents hydrogen, an alkali metal atom, a quaternary ammonium group, or a negative charge forming an inner salt with a quaternized nitrogen atom of the heterocyclic compound. The invention also provides an image receptor element for dye diffusion transfer imaging processes comprising a support and such image-receiving layer.
    Type: Grant
    Filed: October 21, 1987
    Date of Patent: April 11, 1989
    Assignee: AGFA-Gevaert, N.V.
    Inventors: Daniel A. Claeys, Daniel M. Timmerman, Antonius A. Rutges, Eddy A. Michiels, Luc J. Vanmaele, Piet Kok
  • Patent number: 4762759
    Abstract: An image-receiving material adapted for silver complex diffusion transfer processing and for forming a laminate, e.g. serving as an identification document, wherein said material comprises a hydrophobic resin support or resin-coated paper support directly coated on a resin surface thereof with a DTR-image receiving layer containing developing nuclei in a binder medium and comprising in percent by weight on its total weight the following ingredients:2% to 45% of gelatin,25% to 85% of colloidal silica,1.0% to 50% of a copolymer consisting of copolymerized ethylene and an alpha,beta-unsaturated carboxylic acid monomer in free acid or salt form, wherein the polymerized ethylene content is not lower than 80% by weight, and0.2% to 35% of a siloxane forming a reaction product through its siloxane group with the colloidal silica, the dry coverage of the image-receiving layer being in the range of 1 g to 15 g per m2.
    Type: Grant
    Filed: November 7, 1986
    Date of Patent: August 9, 1988
    Assignee: AGFA-Gevaert N.V.
    Inventors: Leon L. Vermeulen, Ludovicus H. Vervloet, Willy P. De Smedt, Piet Kok
  • Patent number: 4748108
    Abstract: In a dye diffusion transfer process the use of a photosensitive element incorporating hydroquinone-type or quinone-type redox-controlled yellow dye-releasing azo compounds containing in the releasable dye moiety a pyrazolone group carrying alkyl, aryl, aralkyl, hetaryl, or heterocyclyl on the 1-position and acylamido, alkylureido, cycloalkylureido, or arylureido on the 3-position, for improved color reproduction of the dye diffusion transfer image as a result of development and a redox-reaction. The invention also provides photosensitive elements incorporating such dye-releasing compounds.
    Type: Grant
    Filed: July 8, 1986
    Date of Patent: May 31, 1988
    Assignee: AGFA-Gevaert, N.V.
    Inventors: Christian C. Van de Sande, Piet Kok
  • Patent number: 4727017
    Abstract: Photographic element comprising a support and a silver halide emulsion layer comprising in said emulsion layer and/or in a water-permeable layer coated at the same side of the support as said emulsion layer a compound corresponding to the following general formula: ##STR1## wherein: each of R.sup.1, R.sup.2, and R.sup.3, which may be the same or different, can represent hydrogen, C.sub.1 -C.sub.8 alkyl, or Alk.sub.1 - X - Alk.sub.2 - Y -, wherein: Alk.sub.1 is C.sub.1 -C.sub.8 alkyl, which may be substituted, X is --O-- or --S--, Alk.sub.2 is C.sub.1 -C.sub.8 alkylene, which may be substituted, and Y is a single bond, --O--, --S--, --CONH--, --SO.sub.2 NH--, or --NHCONH--, R.sup.3 can alternatively represent C.sub.1 -C.sub.8 alkyl-thio, the C.sub.1 -C.sub.8 alkyl group of which can be substituted, at least one of R.sup.1, R.sup.2, and R.sup.3, however, being other than hydrogen and other than C.sub.1 -C.sub.8 alkyl.The invention disclosed includes compounds per se, which correspond to said general formula.
    Type: Grant
    Filed: January 29, 1986
    Date of Patent: February 23, 1988
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Robert J. Pollet, Antoon L. Vandenberghe, Hendrik E. Kokelenberg, Piet Kok