Patents by Inventor Hans Kramb

Hans Kramb 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: 4089851
    Abstract: Disazo dyestuffs of the formula ##STR1## IN WHICH K represents the radical of a coupling component of the benzene, acetoacetic acid arylide, pyrazolone or aminopyrazole series,R.sub.1 and R.sub.2 denote hydrogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or halogen andN denotes 1 or 2,Are suitable for the dyeing of natural and synthetic fibre materials and paper in greenish to reddish yellow shades. The dyeings particularly on polyamide have good to very good light fastness and good fastness to water and washing.
    Type: Grant
    Filed: June 15, 1976
    Date of Patent: May 16, 1978
    Assignee: Bayer Aktiengesellschaft
    Inventor: Hans Kramb
  • Patent number: 4009156
    Abstract: The subject matter of the invention is trisazo dyestuffs, which in the form of the free acid correspond to general formula ##STR1## wherein K.sub.1 denotes the radical of the 2,8-dihydroxynaphthalene-6-sulfonic acid (coupled in alkaline medium) or of the 2-amino-8-hydroxynaphthalene-6-sulfonic acid (coupled in acidic medium),K.sub.2 denotes the radical of a coupling component,R.sub.1 denotes hydrogen or methoxy,R.sub.2 denotes hydrogen or methyl andR.sub.3 denotes hydrogen or chlorine, with the proviso that the total number of sulfonic acid groups is 1 or 2.
    Type: Grant
    Filed: April 25, 1975
    Date of Patent: February 22, 1977
    Assignee: Bayer Aktiengesellschaft
    Inventor: Hans Kramb
  • Patent number: 4008215
    Abstract: Dyestuffs of the formula: ##STR1## are described, wherein K denotes the radical of a coupling component KH which can belong to the benzene, naphthalene or heterocyclic series. The dyestuffs are prepared by one-sided coupling of tetrazotized 4,4'-diamino-2,2'-dimethyldiphenyl with 2-hydroxynaphthalene-8-sulphonic acid in an alkaline medium, and reaction of the intermediate stage with the coupling component KH. The dyestuffs are useful for dyeing natural and synthetic, especially nitrogen containing fibre, materials such as wool and polyamides, including poly-.epsilon.-caprolactam or condensation products of adipic acid and hexamethylene diamine.
    Type: Grant
    Filed: October 9, 1974
    Date of Patent: February 15, 1977
    Assignee: Bayer Aktiengesellschaft
    Inventor: Hans Kramb