Patents by Inventor Karl Kuffner

Karl Kuffner 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: 4436810
    Abstract: Compounds corresponding to the formula: ##STR1## wherein Z represents a radical which completes a condensed aromatic ring system;R.sup.1 represents an n-valent aliphatic or aromatic radical;R.sup.2 represents H, alkyl or aryl,R.sup.3 represents one or more radicals to control the diffusion properties and the activation pH;andn represents 1 or 2,are suitable ED precursor compounds for use in color-photographic recording materials. They are preferably used in a combination with reducible dye-releasers. They are also suitable as so-called scavengers.
    Type: Grant
    Filed: April 29, 1983
    Date of Patent: March 13, 1984
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Karl Kuffner, Paul Marx, Wolfgang Lassig
  • Patent number: 4204867
    Abstract: White couplers which are capable of reacting with color developer oxidation products to form colorless end product with the consumption of four oxidation equivalents and which, therefore have increased absorption capacity for color developer oxidation products correspond to the formula ##STR1## or its tautomeric form, in which R.sup.1 is hydrocarbyl, heterocyclyl attached through a ring carbon, or --CO--R.sup.2R.sup.2 is alkyl, aryl, alkoxy, aminoX is --S-- or --NR.sup.3 --R.sup.3 is hydrogen, same as represented by R.sup.1 or an electron-attaching group.The four-equivalent white couplers may be contained in processing solutions or, in diffusion resistant form, in one or more layers of a colorphotographic material.
    Type: Grant
    Filed: February 10, 1978
    Date of Patent: May 27, 1980
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Karl Kuffner, Wolfgang Lassig, Ernst Meier, Immo Boie, Gertrud Kirchhoff, Helmut Haseler, Herbert Stark
  • Patent number: 4183752
    Abstract: Development inhibitor releasing compounds are thioether compounds capable of releasing on reaction with color developer oxidation products, a diffusible mercaptan that inhibits further development of silver halide. Useful DIR compounds correspond to the formula ##STR1## R.sup.1 represents hydrocarbyl Y represents --S-- or --NR.sup.2 --R.sup.2 represents hydrogen, hydrocarbyl or an electron-attracting substituent.X in its preferred embodiment represents a heteroaromatic group that when split of together with the sulfur atoms forms a silver halide development inhibiting mercaptane.
    Type: Grant
    Filed: February 16, 1978
    Date of Patent: January 15, 1980
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Karl Kuffner, Wolfgang Lassig, Ernst Meier, Erwin Ranz, Karl-Wilhelm Schranz
  • Patent number: 4133958
    Abstract: Desirable 2-equivalent yellow-forming couplers in which a 1,3-diazolone-2-ring as splittable group is attached by the nitrogen in its 1-position to the coupling position of the 2-equivalent yellow-forming coupler and in which the diazolone ring has a C.dbd.C double bond adjacent to the nitrogen atom in its 1-position, have improved photographic properties in particular with respect to improved reactivity on chromogenic development and improved stability of the couplers as well as the dyes produced from them on chromogenic development in a photographic material which has been subjected to storage under moist and/or warm conditions.
    Type: Grant
    Filed: May 6, 1977
    Date of Patent: January 9, 1979
    Assignee: AGFA-Gevaert Aktiengesellschaft
    Inventors: Immo Boie, Karl Kuffner, Gertrud Kirchhoff, Karl-Wilhelm Schranz
  • Patent number: 4059447
    Abstract: Monocyclic oxazolinone-2 structures make good 2-equivalent photographic couplers, the oxazolinone-2 ring splitting during the coupling to form a dye. The couplers can be made by condensing an .alpha.-halocarbonyl compound with an inorganic cyanate in a substantially aprotic solvent that can contain a small amount of water.
    Type: Grant
    Filed: December 23, 1975
    Date of Patent: November 22, 1977
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Ernst Meier, Hans Heinrich Credner, Wolfgang Lassig, Karl Kuffner, Karl-Wilhelm Schranz
  • Patent number: 3973979
    Abstract: Improved 5-pyrazolone couplers of the following formula ##SPC1## wherein R,R.sub.1 R.sub.2,X and A denotes as described hereinafter for use in lightsensitive color photographic materials which are easy to prepare and give rise after chromogenic development to magenta dyes with improved stability to light.
    Type: Grant
    Filed: May 14, 1974
    Date of Patent: August 10, 1976
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Ernst Meier, Hans Glockner, Karl Kuffner, Immo Boie, Karl-Wilhelm Schranz
  • Patent number: 3956311
    Abstract: Preparation of 1-aryl-3-anilino-pyrazolones-(5) by reacting a hydrazine with an ester from the group of dialkoxyacrylic acid ester, trialkoxy propionic acid ester or iminoalkoxy propionic acid ester to produce a .beta.-hydrazine-.beta.-alkoxyacrylic acid ester and then condensing this intermediate product with an aniline to result in the desired anilinopyrazolone. These reactions are carried out in a methanolic solution in the presence of an acetic acid catalyst.
    Type: Grant
    Filed: August 8, 1973
    Date of Patent: May 11, 1976
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Karl Kuffner, Ernst Meier, Hans Glockner
  • Patent number: 3945829
    Abstract: Heterocyclic mercapto compounds are added to a binder layer containing colloidal silver which is comprised in a color photographic multilayer material. The colloidal silver layer may be a yellow filter layer to prevent exposure of the green, and red recording layers to blue light, or an antihalation layer arranged between the layer support and the lowermost light sensitive silver halide emulsion layer. The heterocyclic mercapto compounds reduce the contact fog produced in the (first) developer and increase color density in reversal processing. Additionally there can be present in the colloidal silver layer a sensitizer for the blue, green or red spectral region.
    Type: Grant
    Filed: July 15, 1974
    Date of Patent: March 23, 1976
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Hugo Zorn, Karl Kuffner, Hans Glockner, Jozef Frans Willems, Robrecht Julius Thiers
  • Patent number: 3931221
    Abstract: Anilinopyrazolone are to be prepared in high yields and with a high degree of purity by reacting a salt particularly hydrochloride of a .beta.-arylamino-.beta.-imino-propionic acid ester of one of the tautomeric formulae which are defined hereinafter with a suitable substituted hydrazine.
    Type: Grant
    Filed: December 27, 1973
    Date of Patent: January 6, 1976
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Ernst Meier, Hans Glockner, Karl Kuffner, Immo Boie, Fritz Nittel