Bayer Aktiengesellschaft

Willi Eifler

Roderich Raue

Otto Ganster

Jurgen Schwindt

Holger Meyborg

Berthold Keggenhoff

Hans-Peter Kuhlthau

Gunther Ellendt

Hans J Meiners

Ernst-Heinrich Rohe

Enno Mahlmann

Josef Finkel

The present invention is directed to a process for the production of polyamines of the diphenylmethane series having a high diamine content and a low 2,2'-diamino-diphenylmethane content by condensing aniline with formaldehyde in the presence of hydrochloric acid as catalyst, neutralizing the acid catalyst at the end of the condensation reaction and working up the polyamine mixture thus obtained by distillation, characterized in that

Process for the production of polyisocyanates

This invention relates to a process for the production of non-cellular polyurethane ureas elastomers using a chain-extender mixture produced from asymmetrically alkyl-substituted anilines by condensation with formaldehyde. The chain-extending agents used in the instant invention show medium reactivity to compounds containing isocyanate groups. These chain-extending agents may be processed both in high-pressure and in low-pressure metering and mixing units because they are either liquid at room temperature or can be melted at relatively low temperatures (below 55.degree. C.). The homogeneous, i.e. non-cellular, polyurethane urea elastomers obtained in the instant invention are distinguished by having excellent mechanical properties.

Process for the production of polyurethane urea elastomers

Triaryl-methane dyestuffs which are free from sulfonic acid and carboxylic acid groups and are selected from the group consisting of dyestuffs having one of the following four formulae: ##STR1## wherein R is alkyl, aralkyl, cycloalkyl or aryl; R.sub.1 is hydrogen, alkyl, aralkyl or cycloalkyl; R.sub.2 is alkyl, aralkyl, cycloalkyl or aryl; R.sub.1 and R.sub.2 additionally including divalent alkylene when joined together with the nitrogen or with a carbon atom in the o-position in the ring A to form a heterocyclic ring; R.sub.3 is hydrogen, alkyl, aralkyl, aryl, aralkoxy, aryloxy, halogen, carboxylic acid ester radical, carbonamido, sulfonamido, cyano, nitro, alkylsulfonyl, aryalkylsulfonyl, arylsulfonyl or acyl; and X is the radical of an anion; ##STR2## wherein R is alkyl or cycloalkyl; R.sub.1 is hydrogen, alkyl, aralkyl, cycloalkyl or aryl; R.sub.2 is alkyl, cycloalkyl, aralkyl or aryl, halogen or cyano; R.sub.1 and R.sub.2 additionally include divalent alkylene when joined together with the nitrogen atom or with a carbon atom in the o-position in the ring A to form a heterocyclic ring; R.sub.3 is hydrogen or alkyl; R.sub.4 is alkyl or cycloalkyl; and X is the radical of an anion; ##STR3## wherein R is alkyl or cycloalkyl; R.sub.1 is hydrogen or methyl; R.sub.2 is methyl, aryl, or cycloalkyl; R.sub.3 is hydrogen or alkyl; R.sub.4 is alkyl or cycloalkyl; R.sub.3 and R.sub.4 additionally include divalent alkylene when joined together to form a carbocyclic ring; and X is the radical of an anion; and ##STR4## wherein at least one R is halogen, alkyl, or alkoxy and the other R's are hydrogen, halogen, alkyl, or alkoxy; R.sub.1 is hydrogen or methyl; R.sub.2 is methyl, aryl, or cycloalkyl; and X is the radical of an anion. Process of preparing the above dyestuffs by condensation of an appropriate benzophenone with an aromatic amine or by the oxidation of the corresponding leuco compound. These dyestuffs are particularly useful in dyeing or printing materials made of polymers of acrylonitrile, polymers of as.-dicyanoethylene, and acid-modified aromatic polyesters.

Triaryl-methane dyestuffs

A process for the production of aromatic polyamines comprising condensing primary or secondary aromatic amines with formaldehyde or a formaldehyde precursor in the presence of an acid catalyst and liberating the polyamines on completion of condensation by the addition of a basically reacting reagent, wherein a mixture containing amine, catalyst, aldehyde, precondensates formed therefrom, and water, issuing from a mixer at a maximum temperature of about 40.degree.C., is separated into

Process for the production of aromatic polyamines

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Cologne-Stammheim, Germany

Willi Eifler