Basf Aktiengesellschaft

Basf Se Corporation

Jacques Dupuis

Helmut Hagen

Anton Esser

Hans-Joachim Haehnle

Manfred Niessner

Josef Neutzner

Heinz Friedrich Sutoris

Manfred Winter

Rainer Blum

Rolf-Dieter Kohler

Volker Braig

Michael Kroner

Andreas Koch

Peter Baumann

Ekkehard Schwab

Manfred Patsch

Heinz Eilingsfeld

Michael Kroener

Udo Bergmann

Klaus Pandl

Alexander Aumuller

Ekhard Winkler

Martin Ruebenacker

Hans-Joachim Hähnle

Michael Acker

Martin Wendker

Konrad Mitulla

Peter Trubenbach

Alexander Aum&uuml;ller

Norbert Schall

Claus Kaliba

Berthold Sturm

Martin Rübenacker

Reinhard Hoffmann

Karlheinz Arbogast

The invention relates to a process for producing paper, board and cardboard of high dry strength by separately adding a polymer comprising vinylamine units and a polymeric anionic compound to a paper pulp, dewatering the pulp and drying the paper products, which comprises using as polymeric anionic compound at least one copolymer obtainable by copolymerizing 

Method for producing high dry strength paper, paperboard or cardboard

The present invention relates to an aqueous composition comprising at least one finely divided filler and at least one water-soluble amphoteric copolymer, a process for the preparation of such a composition and its use as an additive in the production of paper, cardboard and board.

Aqueous composition and use thereof for paper production

Aqueous slurries of finely divided fillers which are at least partly coated with polymers and which are obtainable by treating aqueous slurries of finely divided fillers with at least one water-soluble amphoteric copolymer

Aqueous slurries of finely divided fillers, their preparation and their use for the production of filler-containing papers

Process for the preparation of sulfuric acid monoesters of aminoalkanols by reacting sulfuric acid with aminoalkanols and removing the water forming in the reaction from the reaction mixture, sulfuric acid and at least one aminoalkanol being mixed and the hot reaction mixture forming being passed with turbulent flow into a container and being quenched therein with a fluid.

Process for preparing sulfuric monoesters from amino alkanols

Mixture of substances containing compounds with vinyl groups and stabilizers

Stabilized monomer composition

A process for the continuous distillation of thermolabile monomers under reduced pressure in a column includes

Continuous distillation of thermolabile monomers

In a process for the continuous distillation of thermolabile monomers under reduced pressure in the presence of formamide in a column,

An SiO.sub.2 -free, .alpha.Al.sub.2 O.sub.3 -containing catalyst support in the form of a hollow body in which at least part of the outer walls of the hollow body is open can be used to produce a catalyst for dehydrocyanation reactions.

Catalyst supports and catalysts for dehydrocyanation reactions and

A method of stabilizing N-vinylformamide, which may contain customary polymerization inhibitors, against polymerization during storage or transport, comprises adding to the N-vinylformamide monomers of the general formula ##STR1## where R+H, CH.sub.3 ##STR2## R.sup.2 +C.sub.1 -C.sub.4 -alkyl, as stabilizer in amounts of from 1 to 99 .degree.6 by weight, based on the mixture.

Stabilization of monomeric N-vinylformamide

1-Nitroanthraquinone-2-carboxylic acids of the general formula I ##STR1## where X is hydrogen, chlorine or bromine, are prepared by oxidizing a 1-nitro-2-methylanthraquinone of the general formula II ##STR2## with nitric acid in an organic reaction medium.

Preparation of 1-nitroanthraquinone-2-carboxylic acids

Nitrobenzoic acids I ##STR1## (X.sup.1, X.sup.2 =fluorine, chlorine, bromine, hydrogen or nitro) are prepared by oxidizing the corresponding nitrotoluene II ##STR2## with nitric acid in the presence of sulfuric acid and vanadium(V) compounds, and anthranilic acids III ##STR3## (Y.sup.1, Y.sup.2 =fluorine, chlorine, bromine, hydrogen or amino) are prepared from the nitrobenzoic acids I by reduction.

Preparation of nitrobenzoic and anthranilic acids

A process for the preparation of 4-sulfonated anthranilic acids by sulfonation of ortho-nitrotoluenes with chlorosulfonic acid or oleum followed by oxidation of the methyl group and, finally, reduction of the nitro group.

Process for the preparation of sulfonated anthranilic acids

3-Methylquinoline-8-carboxylic acid I ##STR1## and derivatives thereof are prepared by reacting o-toluidine II or a derivative thereof ##STR2## with methacrolein II ##STR3## in 70-90% strength by weight sulfuric acid in the presence of iodine or of an iodine compound, and oxidizing the resulting 3,8-dimethylquinoline IV or a derivative thereof ##STR4## with nitric acid in a solution containing sulfuric acid, in the presence of vanadium ions, by a process in which, in the sulfuric acid-containing reaction solution of the 3,8-dimethylquinoline IV, the byproducts of the reaction are first decomposed by oxidation, the resulting 3,8-dimethylquinoline solution is concentrated by distillation and the 3,8-dimethylquinoline is then oxidized in situ with nitric acid to give the 3-methylquinoline-carboxylic acid.

Preparation of 3-methylquinoline-8-carboxylic acid

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Ludwigshafen, Germany

Jacques Dupuis