Bayer Aktiengesellschaft

Horst Harnisch

Roderich Raue

Hans-Jochem Riebel

Reinhard Lantzsch

Dieter Arlt

Manfred Jautelat

Rainer A Fuchs

Rolf Schroder

Alfred Brack

Uwe Claussen

Udo Eckstein

Adolf Friedrich

Horst Berneth

Klaus Wunderlich

Otto S Wolfbeis

Hans-Peter Kuhlthau

Peter Roschger

Carl-Wolfgang Schellhammer

Peter Rasche

Matthias Kocher

Frank Arndt

Jurgen-Rolf Hassdenteufel

Edgar Siegel, Deceased

Fritz Peter Schafer

Plastics are colored with at least one dyestuff of the following formula (I) ##STR1## in which the substituents have the meaning given in the description.

Dyestuffs and their use for mass-coloration of plastics

New naphthalimides, useful as additives in toners for controlling the charge and conductivity, of the formula ##STR1## in which R represents C.sub.1 - to C.sub.22 -alkyl,

New naphthalimides, toners containing these and the use of the new

Positively charged electrophotographic toners contain, besides customary resin and pigment particles, an additive which increases the cationic charge and has the general formula

Electrophotographic toners with cationic charge increasing additive

The invention relates to positively charged electrophotographic toners which, in addition to customary resin and pigment particles, contain an additive which intensifies the cationic charge, of the general formula ##STR1## wherein R.sup.1 and R.sup.2 independently of one another represent H, C.sub.1 -C.sub.22 -alkyl, allyl, cyclohexyl, phenyl-C.sub.1 -C.sub.2 -alkyl or phenyl and

Electrophotographic toners with substituted

Heteropolyacid salts of the formula ##STR1## R.sup.1 and R.sup.2 independently of one another stand for hydrogen, chlorine, bromine, hydroxyl, C.sub.1 - to C.sub.4 -alkoxy, nitro or carboxyl,

Colorless salts of heteropolyacids as charge control substances in toners

To quench the fluorescence generated by anionic optical brighteners, virtually colourless, water-soluble, cationic compounds are used which contain at least one cationic group per molecule or per repeating structural unit and at least two nitro group-free naphthalene-peridicarboxylic acid imide groups per molecule or at least one such group per repeating structural unit.

Process for the quenching of fluorescence, and new cationic

Positively charged electrophotographic toners contain, in addition to conventional resin and pigment particles, an additive reinforcing the cationic charge, of the general formula ##STR1## in which R.sup.1 and R.sup.2 each represent hydrogen, chlorine,

Naphthalic acid imides electrophotographic toners

Postively charged electrophotographic toners contain, in addition to conventional resin and pigment particles, an additive reinforcing the cationic charge, of the general formula ##STR1## in which R.sup.1 and R.sup.2 each represent hydrogen, chlorine, bromine, hydroxyl, C.sub.1 -C.sub.4 -alkoxy or carboxyl,

Electrophotographic toners containing an additive reinforcing the

A light-collecting system, which contains a coumarin derivative of the formula ##STR1## in which T denotes O or NR.sub.4,

Light-collecting coumarin derivatives

To quench the fluorescence produced by anionic fluorescent brighteners use is made of virtually colorless, water-soluble cationic or amphoteric compounds which contain in the molecule at least one ammonium group, at least two aryl, arylene, hetaryl and/or hetarylene groups and at least one nitro group.

Process for quenching fluorescence, and new cationic or amphoteric

Compounds of the formula ##STR1## wherein Y is ##STR2## M is hydrogen, or an alkali metal or ammonium ion, X is --O-- or an amino group,

Chromogenic and fluorogenic esters for photometric or fluorimetric

Compounds of the formula ##STR1## in which M each independently is hydrogen, an alkali metal ion, an ammonium ion, or an ammonium ion substituted by up to four C.sub.1 to C.sub.5 -alkyl and/or hydroxyalkyl radicals, are fluorogenic and suitable for the fluorimetric determination of phosphatases.

Fluorogenic phosphate esters of hydroxy-pyrene-sulfonic acids for

Dyestuffs of the formula ##STR1## wherein R represents hydrogen or optionally substituted alkyl,

Cationic dyestuffs, a process for their preparation, and their use for

Phosphate esters of hydroxy-pyrene-sulfonic acids

A light-collecting system, characterized in that it contains a coumarin derivative of the formula ##STR1## in which T denotes O or NR.sub.4, in which

Growing community of inventors

Much, Germany

Horst Harnisch