Bayer Aktiengesellschaft

Kemira Oyj

Akzo Nobel Chemicals International B.v.

Karlheinrich Meisel

Horst Berneth

Gerd-Friedrich Renner

Bernd Thiele

Lothar Puppe

Alfred Brack

Johan Kijlstra

Karl-Rudolf Gassen

Arno Nennemann

Heinz U Blank

Roderich Raue

Hubertus Psaar

Klaus Walz

Karin Hassenruck

Hans Schulze

Henry Giera

Fritz Puchner

Friedrich-Wilhelm Ullrich

Willi Streicher

Thomas Hübbe

Horst Zwick

Lars Obendorf

Joachim K&ouml;nig

Gunther Klag

Felix Reichel

Reiner Ditzer

J&uuml;rgen Reiners

Dieter Irmscher

Thomas Hubbe

Carsten Gerdes

Armin Spaniol

Nikolaus Schulz

Dietmar Fuchs

Lothar Klein

Branislav Boehmer

Thomas Huebbe

Karl Lange

Use of silica sols containing sulfonic acid groups and/or mercapto groups as microparticles in paper production, in particular for paper retention.

Paper production with modified silica gels as microparticles

A process for the preparation of polymeric condensates, wherein the reaction mixture is fed at least once during the condensation reaction through a zone of high energy density which has an energy density of at least 10J/m.

Process for the preparation of polymeric condensates and their use

The invention relates to a novel process for the preparation of polycondensate solutions based on polyamidoamine/epichlorohydrin resins that gives products having a very low content of organic chlorine compounds, in particular a 1,3-dichlorophenol-2-propanol content of <0.1%, in combination with high activity and good shelf-life.

Wet-strength agent with low DCP content

.beta.-Hydroxyalkylpicolinium salts of the formula (I) ##STR1## wherein A, R.sup.1 to R.sup.3 and X have the meanings given in the description, which are obtained by reaction of picolines of the formula (II) ##STR2## with alkylene oxides of the formula (III) in the presence of a 1- to 3-basic acid and in water or an organic solvent as the reaction medium and are used as intermediate products for the preparation of cationic dyestuffs, and dyestuff preparations comprising such cationic dyestuffs.

Process for the preparation of beta-hydroxyalkypicolinium salts

Method for reducing the toxicity of spent liquors and novel cationic dyes

Indoles of the formula ##STR1## can be prepared by reaction of a phenylhydrazine of the formula ##STR2## which is unsubstituted in at least one ortho-position, with a ketone of the formula ##STR3## in an aqueous medium in the presence of an acid compound, less than 5 equivalents, based on 1 mol of phenylhydrazine, of an acid compound having a pK value of 1.3-4.5 being employed.

Process for the preparation of indoles

Compounds of the formula ##STR1## in which R.sup.1 /R.sup.2 are alkyl, cycloalkyl, aralkyl or alkylene,

Chromogenic enamine compounds, their preparation and use as color formers

4,4-diaryldihydroquinazolones of the formula ##STR1## wherein X.sup.1, X.sup.2 and X.sup.3, independently of one another, denote hydrogen, halogen, alkyl, aryl, alkanoylamino, aroylamino, heteryl, NY.sup.1 Y.sup.2, OY.sup.3 or SY.sup.3, at least one of the radicals

Chromogenic 4,4-diaryldihydroquinazolones

4,4-diaryldihydroquinazolones of the formula ##STR1## wherein X.sup.1, X.sup.2 and X.sup.3, independently of one another, denote hydrogen, halogen, alkyl, aryl, alkanoylamino, aroylamino, heteryl, NY.sup.1 Y.sup.2, OY.sup.3 or SY.sup.3, at least one of the radicals X.sup.1, X.sup.2 or X.sup.3 standing for NY.sup.1 Y.sup.2, OY.sup.3 or SY.sup.3,

4,4-Diaryl-2-oxobenzo-3,1-oxazines of the general formula ##STR1## wherein X.sup.1, X.sup.2 and X.sup.3, independently of one another, denote hydrogen, halogen, alkyl, aryl, alkanoylamino, aroylamino, heteryl, NY.sup.1 Y.sup.2, OY.sup.3 or SY.sup.3,

Chromogenic 4,4-diaryl-2-oxobenzo-3,1-oxazines

Cationic enamine dyestuffs of the general formula ##STR1## in which the symbols have the meaning given in the description, are used for dyeing natural and synthetic substrates and compositions which can be dyed with cationic dyestuffs, in particular paper.

Cationic enamine dyestuff indolylmethine derivatives

Growing community of inventors

Odenthal, Germany

Karlheinrich Meisel