Bayer Aktiengesellschaft

Paul Uhrhan

Ernst Roos

Reinhard Lantzsch

Dieter Arlt

Harald Oertel

Ingeborg Hammann

Hans-Jochem Riebel

Bernhard Homeyer

Fritz Maurer

Gerhard Grogler

Rolf Schroder

Jurgen Schwindt

Wolfgang Hofer

Edmund Krauthausen

Hans Schroer

Wolfgang Behrenz

Rudiger Schubart

Horst Behre

Holger Heidenreich

Heinz-Ulrich Blank

Theo Kempermann

Kurt-Rainer Stahlke

Lothar Ruetz

Manfred Abele

Gerwolf Quaas

Fritz Pohl

When 2-naphthylamine-1,5-disulphonic acid is precipitated from the as-sulphonated reaction mixtures by dilution, a purer product is obtained, with a low level of adherent sulphuric acid, if the precipitation by dilution of the reaction mixture is carried out under precisely defined conditions.

Process for the isolation of 2-naphthylamine-1,5-disulphonic acid

The present invention relates to new dihydrobenzothiazine compounds, to the production thereof and to the use thereof as stabilizers and co-stabilizers against the oxidative and/or thermal degradation of organic polymers.

Dihydrobenzothiazine compounds and the preparation thereof

Process for the preparation of 2,3-Dihydro-4H-1,4-benzothiazines by cyclisation of suitable 2-(2-Hydroxyalkyl)-thioanilines under elimination of water in the presence of phosphorous acid.

Process for the production of 2,3-Dihydro-4H-1,4-benzothiazines

The instant invention is directed to polyurethane plastics which may be cellular, produced by reaction of polyisocyanates with relatively high molecular weight polyhydroxyl compounds and, optionally, low molecular weight polyhydroxyl compounds, and diamines, said polyurethane plastic containing structural units corresponding to the general formula ##STR1## in which R' represents a straight or branched divalent aliphatic, cycloaliphatic or aromatic radicals containing from 2 to 20 carbon atoms and

Polyurethane plastics containing thio groups

The invention relates to new methylol derivatives of 2,2,6,6-tetraalkylpiperidines, to their production and to their use as chemically attached stabilizers for polymers containing reactive OH- and NH-groups.

Methylol derivatives of 2,2,6,6-tetraalkylpiperidines and their

The invention is related to modified polyurethanes which have a permanent, wash-fast, acidresistant, dry cleaning-resistant and solvent-resistant stabilization based on 2,2,6,6-tetraalkyl-piperidine light protective agents. These stabilizers are an integral constituent of the polyurethanes, that is to say they take part in the polyurethane synthesis by the reaction of an H-active reactive group (for example NH.sub.2, NH-alkyl, CO--NH--NH.sub.2, NH--CO--NH--NH.sub.2, OH or some other H-active group) of the 2,2,6,6-tetraalkyl-piperidine derivatives with isocyanate groups of polyisocyanates or isocyanate prepolymers.

Permanently stabilized polyurethanes

This invention relates to permanently stabilized polymers containing substituted piperidine derivatives chemically attached to the polymer molecule through O- or N-atoms. Compounds based on 2,2,6,6-tetraalkyl piperidines have now been found which, on the one hand, have a very high stabilizing activity and, on the other hand, contain one or more reactive groups through which they are able to react with the polymers to be stabilized. Stabilized polymers, preferably polyurethane elastomer filaments, films and coatings with a permanent washing-resistant, boiling resistant, acid-resistant, dry-cleaning-resistant and solvent-resistant stabilization based on 2,2,6,6-tetraalkyl piperidine light stabilizers are thus obtained.

Permanently stabilized polymers produced by after-treatment with

This invention relates to new polyurethane resins produced by a process in which aromatic diamines containing thio-groups are used as chain-lengthening agents.

Process for making polyurethane resins via thio-group containing diamines

According to the invention there are obtained modified polyurethanes which have a durable, wash-fast, acid-resistant, cleaning-resistant and solvent-resistant stabilization on the basis of 2,2,6,6-tetraalkyl-piperidine light protective agents. The stabilizers are integral constituents of the polyurethanes, that is to say they are built into the polyurethane chain by a chain lengthening reaction in which two H-active reactive groups (preferably from the series of primary or secondary amino groups, carboxylic acid hydrazide, carbazic ester or semicarbazide groups) of a 2,2,6,6-tetraalkyl piperidine derivative react with isocyanate groups of polyisocyanates or isocyanate prepolymers, optionally in the presence of the usual chain lengthening agents.

Cyanamides which may be obtained by reacting cyanogen chloride with certain piperidines can be used as stabilizers for synthetic polymers against discoloration and degradation under the effects of visible and/or UV-light, heat and/or atmospheric influences.

Cyanamide stabilizers

Thiazolinylamino-piperidine derivatives can be obtained by reacting a .beta.-chloroisothiocyanate with a 4-amino-piperidine. The resulting products can be used as stabilizers for synthetic polymers against discoloration and degradation under the effect of visible and/or UV-light, heat and/or atmospheric influences.

Thiazolinylamino-piperidine derivatives

O-(1-Phenyl-2-carbalkoxy-vinyl)-thionophosphoric (phosphonic) acid esters and ester-amides of the formula ##STR1## in which R and R.sub.4 each independently is alkyl with 1 to 6 carbon atoms, R.sub.1 is hydrogen or methyl, R.sub.2 is alkyl, alkoxy or alkylthio each with 1 to 4 carbon atoms, cyano, halogen, or phenyl, R.sub.3 is alkyl, alkylthio or alkylamino with 1 to 6 carbon atoms, or phenyl, X is oxygen or sulfur, and N is 0, 1, 2, 3, 4 or 5, Which possess insecticidal and acaricidal properties.

O-(1-Phenyl-2-carbalkoxy-vinyl)-thionophosphoric (phosphonic) acid

Stabilizers according to the invention are used for stabilizing synthetic polymers against discoloration and degradation under the effect of visible and/or UV light, heat and/or atmospheric influences.

Stabilization of synthetic polymers

Sulphenamides are obtained by reacting N-chlorothiophthalimide with compounds containing one or two olefinic double bonds. These products retard vulcanization of natural or synthetic rubber.

Sulphenamides, their production and their use as vulcanization retarders

O,O-Dialkyl-O-(1-phenyl-2-carbalkoxyvinyl)-thionophosphoric acid esters of the formula ##STR1## in which R, R.sub.3 and R.sub.4 each independently is alkyl with 1 to 6 carbon atoms,

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Cologne, Germany

Paul Uhrhan