Patents by Inventor Arnfried Melzer

Arnfried Melzer 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).

  • Dye diffusion transfer process employing compounds that release sulfonamide dye providing radicals
    Patent number: 4198235
    Abstract: Useful non-diffusible dye-giving compounds for the photographic dye diffusion transfer process are dye sulfonamides derived from enolamines or endiamines or tautomers thereof. The dye-giving compounds are oxidized by developer oxidation products and subsequently split under the conditions of alkaline development to release diffusible dyes. The compounds are of the following formula ##STR1## in which X is a dye moiety and R.sub.1, R.sub.2 and R.sub.3 have meanings given hereinafter.
    Type: Grant
    Filed: June 21, 1978
    Date of Patent: April 15, 1980
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Hans Vetter, Walter Puschel, Arnfried Melzer, Manfred Peters
  • Photographic color developer composition
    Patent number: 4155764
    Abstract: A photographic color developer composition containing a color developer compound and an antioxidant wherein it contains a water-soluble enolizable .alpha.-aminocarbonyl compound as antioxidant is provided. Resistance to atmospheric oxygen of photographic color developer baths is improved.
    Type: Grant
    Filed: May 17, 1977
    Date of Patent: May 22, 1979
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Arnfried Melzer, Erwin Schon
  • Photographic color developer composition
    Patent number: 4142895
    Abstract: A color developer composition is provided which has substantially improved protection against oxidation of the color developer and excellent sequestering properties characterized in that the composition comprises an .alpha.-aminocarbonyl compound, an organo-phosphonic acid and an aminocarboxylic acid.
    Type: Grant
    Filed: January 5, 1978
    Date of Patent: March 6, 1979
    Assignee: Agfa Gevaert Aktiengesellschaft
    Inventors: Karl Frank, Arnfried Melzer
  • Sulfonamido dye releaser in photographic dye diffusion transfer
    Patent number: 4110113
    Abstract: In the photographic dye-diffusion transfer process use is made of dye-giving compounds, which are non diffusing in photographic binder layers, and which during development if oxidized imagewise in accordance with the silver halide developed are split owing to the alkali of the developer composition to release diffusing dyes, which are transferred to an image-receiving layer. The dye-giving compounds have the formulaY--NH--Ar--NH--SO.sub.2 --Xar represents an arylene radical such that the group Y--NH-- is attached to the group --NH--SO.sub.2 --X through a chain of n(n=1,2,3, or 4) vinylene groups which are part of the arylene radical;X represents the radical of a dye or dye precursor;Y represents a --COR or --SO.sub.2 R radical; andR represents an alkyl, aryl or heterocyclic group and can constitute part of a second dye moiety.
    Type: Grant
    Filed: June 16, 1977
    Date of Patent: August 29, 1978
    Assignee: AGFA-Gevaert Aktiengesellschaft
    Inventors: Arnfried Melzer, Paul Marx, Walter Puschel