Patents by Inventor Walter Frans De Winter

Walter Frans De Winter 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: 4075023
    Abstract: Oxazolidines and tetrahydro-1,3-oxazines which are substituted with 3-acryloyl or 3-methacryloyl groups are prepared by adding to an excess of a ketone and in the presence of a hydrogen chloride acceptor, about equimolecular amounts of a 2- or 3-amino lower alkanol and of acryloyl chloride or methacryloyl chloride, heating the mixture, and eliminating the unreacted ketone by destillation. The ketone corresponds to the formula: ##STR1## wherein R.sub.1 = alkyl (1-4 C),R.sub.2 = alkyl (1-4 C) or phenyl, orR.sub.1 and R.sub.2 together represent the atoms necessary to complete an alicyclic group.These unsaturated oxazolidines and tetrahydro-1,3-oxazines may be homo- or copolymerized, and these polymers may be used as plasticizers for gelatin, e.g. in photographic layers containing gelatin.
    Type: Grant
    Filed: December 19, 1972
    Date of Patent: February 21, 1978
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Jan Josef Priem, Walter Frans De Winter
  • Patent number: 4047957
    Abstract: A process is described for the hardening of a protein-aceous layer or layers, more especially of gelatin layers, e.g. gelatin layers in a photographic material, by the application on this layer or layers of a coating composition comprising a low molecular weight, fast-acting, carboxyl group-activating hardening agent in combination with a film-forming, hydrophilic, polymeric, fast-acting hardening agent carrying one or more carboxyl group-activating substituents.
    Type: Grant
    Filed: February 6, 1976
    Date of Patent: September 13, 1977
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Walter Frans De Winter, Daniel Maurice Timmerman
  • Patent number: 4039463
    Abstract: Carrier beads for use in an electrostatographic developer mixture comprise a glass core or iron-containing metal core enveloped with a coating of a copolymer of N-vinylcarbazole, trialkoxyvinylsilane and/or triacetoxyvinylsilane and optionally one or both of the monomers of the group consisting of C.sub.1 -C.sub.4 alkyl (meth)acrylate and styrene.
    Type: Grant
    Filed: April 16, 1975
    Date of Patent: August 2, 1977
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Pierre Richard De Roo, Walter Frans De Winter, Jan Jozef Priem, Yvan Karel Gilliams
  • Patent number: 4033770
    Abstract: Process and material for the production and use of pressure sensitive and for heat sensitive and/or solvent sensitive decalcomanias, formed according to the principles of the silver complex diffusion transfer process.
    Type: Grant
    Filed: April 4, 1975
    Date of Patent: July 5, 1977
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Louis Maria De Haes, Leon Louis Vermeulen, Hugo Karel Gevers, Walter Frans De Winter
  • Patent number: 4022622
    Abstract: Polymeric particles are homogeneously dispersed in aqueous medium by a process which comprises dissolving a water-insoluble film-forming polymer in a water-insoluble, ethylenically unsaturated monomer which is liquid at room temperature. The solution formed is dispersed by stirring in an aqueous solution of a hydrophilic colloid and of a dispersing agent, stirring being continued until a stable dispersing of polymer-in-monomer solution droplets having a diameter between 1 and 10 microns, preferably between 1 and 6 micron, in said aqueous solution is obtained. While continuously stirring the dispersion in the presence of a free-radical forming polymerization initiator, the dispersion is heated at the decomposition temperature of said polymerization initiator to effect polymerization of the water-insoluble, liquid monomer and to form an aqueous dispersion of solvent-free polymer particles.
    Type: Grant
    Filed: March 1, 1976
    Date of Patent: May 10, 1977
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Daniel Maurice Timmerman, Victor Jan Thijs, Walter Frans De Winter, Frans Henri Claes, Hubert Vandenabeele
  • Patent number: 3993850
    Abstract: A recording material is described, which comprises a support of paper or of synthetic polymer and an electroconductive layer on at least one side of the support. The surface resistance of this electroconductive layer is not more than 10.sup.11 ohms per sq. at a relative humidity of 15%. The layer consists or includes a major proportion of a water-soluble polymer resulting from the amino alkylation of polyethyleneimine with an epoxy compound bearing a quaternary ammonium end group.The electroconductive layers may be used as antistatic layers in a photographic silver halide recording material. When covered with a photoconductive coating the electroconductive layer may be used in electrophotographic recording materials. When an insulating layer is applied on the electroconductive layer an electrographic recording material is formed.
    Type: Grant
    Filed: January 3, 1975
    Date of Patent: November 23, 1976
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Daniel Maurice Timmerman, Walter Frans De Winter
  • Patent number: 3986877
    Abstract: A method is described for developing silver halide emulsions wherein development is activated by incorporating in the developing composition or the emulsion a homopolymer or copolymer comprising (meth)acrylate or (meth)acrylamide units in which the ester linked or amide linked group contains at least one thioether sulphur atom.
    Type: Grant
    Filed: August 8, 1974
    Date of Patent: October 19, 1976
    Assignee: AGFA-Gevaert, N.V.
    Inventors: Daniel Maurice Timmerman, Robert Joseph Pollet, Jozef Frans Willems, Walter Frans De Winter
  • Patent number: 3969283
    Abstract: A recording material is described, which comprises a support of paper or of synthetic polymer and an electroconductive layer on at least one side of the support. The surface resistance of this electroconductive layer is not more than 10.sup.11 ohms per sq. at a relative humidity of 15 %. The layer consists or includes a major proportion of a water-soluble polymer resulting from the amino alkylation of polyethyleneimine with an epoxy compound bearing a quaternary ammonium end group.The electroconductive layers may be used as antistatic layers in a photographic silver halide recording material. When covered with a photoconductive coating the electroconductive layer may be used in electrophotographic recording materials. When an insulating layer is applied on the electroconductive layer an electrographic recording material is formed.
    Type: Grant
    Filed: January 3, 1975
    Date of Patent: July 13, 1976
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Daniel Maurice Timmerman, Walter Frans De Winter
  • Patent number: 3950169
    Abstract: A recording material is described, which comprises a support of paper or of synthetic polymer and an electroconductive layer on at least one side of the support. The surface resistance of this electroconductive layer is not more than 10.sup.11 ohms per sq. at a relative humidity of 15%. The layer consists or includes a major proportion of a water-soluble polymer resulting from the amino alkylation of polyethyleneimine with an epoxy compound bearing a quaternary ammonium end group.The electroconductive layers may be used as antistatic layers in a photographic silver halide recording material. When covered with a photoconductive coating the electroconductive layer may be used in electrophotographic recording materials. When an insulating layer is applied on the electroconductive layer an electrographic recording material is formed.
    Type: Grant
    Filed: January 3, 1975
    Date of Patent: April 13, 1976
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Daniel Maurice Timmerman, Walter Frans De Winter
  • Patent number: 3941727
    Abstract: Polymeric particles are homogeneously dispersed in aqueous medium by a process which comprises dissolving a water-insoluble film-forming polymer in a water-insoluble, ethylenically unsaturated monomer which is liquid at room temperature. The solution formed is dispersed by stirring in an aqueous solution of a hydrophilic colloid and of a dispersing agent, stirring being continued until a stable dispersing of polymer-in-monomer solution droplets having a diameter between 1 and 10 microns, preferably between 1 and 6 micron, in said aqueous solution is obtained. While continuously stirring the dispersion in the presence of a free-radical forming polymerisation initiator, the dispersion is heated at the decomposition temperature of said polymerisation initiator to effect polymerisation of the water-insoluble, liquid monomer and to form an aqueous dispersion of solvent-free polymer particles.
    Type: Grant
    Filed: October 23, 1973
    Date of Patent: March 2, 1976
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Daniel Maurice Timmerman, Victor Jan Thijs, Walter Frans De Winter, Frans Henri Claes, Hubert Vandenabeele