Sterling Drug Inc.

The Hilton-davis Chemical Co.

Raymond E Werner

Nathan N Crounse

John W Delaney

James C Heath

James E Kassner

Robert W Rebhahn

This invention relates to improved processes for the manufacture of quinolinic acid run with a higher concentration of reactants in the initial step wherein quinoline is oxidized with hydrogen peroxide in an aqueous sulfuric acid solution in the presence of copper sulfate to prepare copper quinolinate, and in subsequent steps converting the copper quinolinate from the initial step to quinolinic acid by treating the copper salt with alkali to form the water soluble alkali salt form of quinolinic acid precipitating the copper as insoluble cupric oxide and thereafter treating the soluble alkali salt form with acid to obtain the quinolinic acid, the improvement whereby the reaction of the initial step is carried out in a thermally controllable and safe manner and the formation of by-products is minimized which comprises in the initial step adding separately either in portion-wise multiple and approximately equal portions or adding continuously and simultaneously over a period of time each of the following, the sulfuric acid, the quinoline and the hydrogen peroxide to an aqueous solution of the copper sulfate over such time intervals of sufficient length spaced between each group of portion-wise additions or at such a rate as to allow the hydrogen peroxide to react to maintain an unreacted hydrogen peroxide concentration in the reaction of between approximately three and approximately fifteen percent.

Process for preparing quinolinic acid

This invention relates to a method for imparting a red hue to edible materials by incorporating a stabilized solid solution consisting essentially of FD & C Red No. 3 and edible gelatin; to said solid solutions; to edible materials colored with the solid solution and to the process for preparing the solid solutions.

Coloring agents for edible materials

Novel crystalline needle forms of the fluorescent compounds disodium 4,4'-bis(4-anilino-6-morpholino-s-triazin-2-ylamino)-2,2'-stilbenedisulfon ate and disodium 4,4'-bis(4,6-dianilino-s-triazin-2-ylamino)-2,2'-stilbenedisulfonate, useful as optical brightening agents, particularly when incorporated into detergent compositions. The novel crystalline forms are prepared by heating the compound in an aqueous alkaline medium containing excess amine reactant.

Detergent compositions containing novel crystalline forms of optical

Novel crystalline forms of optical brighteners

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Cincinnati, OH, United States of America

Raymond E Werner