Bayer Aktiengesellschaft

Wolfgang Reichmann

Klaus Konig

Adolf Richartz

Werner Rasshofer

Manfred Schonfelder

Ulrich Knipp

Rudolf Heusch

Josef Pedain

Kurt Findeisen

Kuno Wagner

Richard Kopp

Walter Schafer

Manfred Dietrich

Hans-Walter Illger

Hans-Joachim Meiners

Peter Seifert

Heinz Muller

Klaus Seel

Walter Schneider

Johannes Koster

Heinz-Georg Nordmann

Gunther Lehnert

Kalus Koenig

The disclosed invention is concerned with porous substrates impregnated with moisture curing polyurethane oligomers incorporating tertiary nitrogen atoms and free aromatic isocyanate groups in which the yellowing tendency of these isocyanates is diminished or supressed by the inclusion of specific light protection agents. These agents are either substituted oxalanilides or indole or indoline derivatives. The impregnated substrates cure rapidly when exposed to moisture to yield rigid structures suitable as a replacement for Plaster of Pairs in medicinal and veterinary bandaging applications.

Self-curing material for the production of a weather-resistant,

A first reaction mixture, prepared from (a) isocyanates with isocyanate contents of from 5 to 50% and (b) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component 'a' to component 'b' of 0.8:1 to 5:1, from 0.1 to 20% of a blowing agent and, optionally, other known additives, is introduced into the rigid cavity of a closed mold. After this mixture has become resistant to permeation, but is still compressible, a second reaction mixture, either the same or different from the first reaction mixture, prepared from (c) isocyanates having isocyanate contents of from 5 to 50% and (d) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component 'c' to component 'd' of from 0.8:1 to 5:1, specific internal mold release agents and optionally blowing agents and other additives, is introduced into the mold, such that it surrounds the first mixture and compresses it. A third, optional, reaction mixture, the same as or different from the second mixture, may also be employed in a manner similar to the introduction of the second mixture. The final composite plastic part releases smoothly from the mold.

Process for the production of a cellular composite plastic part

A process for producing storage-stable solutions of pyrocarbonic acid dialkyl esters in organic liquids inert to these esters comprising adding certain carbonyl compounds, sulfonyl compounds and/or thiourea to these pyrocarbonic acid dialkyl ester solutions. Also the use of these carbonyl compounds, sulfonyl compounds and/or thiourea for producing stabilized polyisocyanate preparations suitable for the production of polyurethane foams.

Use of carbonyl compounds, sulfonyl compounds and/or thioureas as

A homogeneous, storage-stable, emulsifier-free polyol mixture having a high mixed OH-number and a high ethylene glycol content comprising 100 parts of a relatively high molecular weight polyalkylene oxide polyol having an OH-number of from 20 to 210, which contains at least 5%, and less than 80%, by weight, of terminal ethylene oxide blocks, from 0.1 to 30 parts of a low molecular weight diol mixture having an OH-- number of 1200 to 1650 in the form of a reaction product of 1 mole of ethylene glycol with 0.1 to 0.5 moles of propylene oxide, optionally, up to 5 parts of di- and/or tri-functional compounds containing reactive hydrogen atoms and having a molecular weight of from 32 to 399, and optionally, other auxiliaries and additives known in the production of polyurethanes. Also, polyurethanes produced using these polyol mixtures.

Homogeneous, storage-stable polyol compositions of high ethylene glycol

A first reaction mixture, prepared from (a) aromatic isocyanates with isocyanate contents of from 5 to 50%, and (b) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component 'a' to component 'b' of 0.8:1 to 5:1, from 0.1 to 20% of a blowing agent and, optionally, other known additives, is introduced into a closed mold with a rigid cavity. After this mixture has become resistant to permeation, but is still compressible, a second reaction mixture, prepared from (c) aliphatic and/or cycloaliphatic polyisocyanates having isocyanate contents of from 5 to 50% and (d) compounds with molecular weights of from 32 to 10,000 which contain at least two isocyanate-reactive hydrogen atoms, in an equivalent ratio of component 'c' to component 'd' of from 0.8:1 to 5:1, an internal mold release agent and optionally blowing agents and other additives, is introduced into the mold, such that the second mixture surrounds the first mixture and compresses it. A third, optional, reaction mixture, the same as or different from the second mixture, may also be employed in a manner similar to the introduction of the second mixture. The final composite plastic part releases smoothly from the mold and evidences good lightfast and colorfast properties.

Process for the production of a lightfast and colorfast composite

A homogeneous, storage-stable, emulsifier-free polyol mixture having a high mixed OH-number and a high ethylene glycol content comprising 100 parts of a relatively high molecular weight polyalkylene oxide polyol having an OH-number of from 20 to 210, which contains at least 5%, and less than 80%, by weight, of terminal ethylene oxide blocks, from 0.1 to 30 parts of a low molecular weight diol mixture having an OH-number of 1200 to 1650 in the form of a reaction product of 1 mole of ethylene glycol with 0.1 to 0.5 moles of propylene oxide, optionally, up to 5 parts of di- and/or tri-functional compounds containing reactive hydrogen atoms and having a molecular weight of from 32 to 399, and optionally, other auxiliaries and additives known in the production of polyurethanes. Also, polyurethanes produced using these polyol mixtures.

The present invention is directed to a process for the production of polyurea-based microcellular moldings comprising reacting

Process for the production of microcellular moldings from diisocyanate

A single-phase, storage-stable, emulsifier-free polyol mixture comprising 100 parts of a relatively high molecular weight polyoxyalkylene polyol of OH number from 20 to 120, which has at least 5% and less than 80% by weight, of terminal oxyethylene blocks; from 1 to 100 parts of a low molecular weight diol mixture which is a reaction product of ethylene glycol, butane diol-1,4, or a mixture of ethylene glycol and butane diol-1,4, with from 0.05 to 0.50 mols of alkyl oxiranes; from 0.1 to 5 parts of solubilizing additives comprising one or more salts, the cations of which are from Groups I, II and III of the Periodic Table, ammonium or mono- to tetra-alkyl ammonium ions, and the anions of which are produced by removing at least one proton from an acid having a K.sub.s value of at least 10.sup.-7 ; and, optionally, other compounds having isocyanate-reactive hydrogen atoms and other auxiliaries and additives for polyurethane production. Also polyurethanes produced using these polyol mixtures.

Single-phase, storage-stable polyol compositions containing salts and

The present invention relates to a process for the production of specific polyisocyanates by reacting diamines containing hydrogen atoms which are active in the context of the isocyanate addition reaction with excess quantities of organic diisocyanates. The invention also relates to a modification of the above process characterized in that the diamines are reacted first with excess quantities of a first diisocyanate after which the thus obtained reaction product which contains a urea group and a biuret group is reacted in a second stage with a second diisocyanate. The invention also relates to the use of polyisocyanates as the isocyanate component in the production of polyurethane plastics by the isocyanate-polyaddition process.

Polyisocyanates, preparation and use thereof

A process for the preparation of polyisocyanates containing biuret and/or higher polyuret groups by reacting secondary diamines with diisocyanates characterized in that the reaction is carried out in the presence of catalytic quantities of strong acids which form mixed carbamic acid anhydrides with isocyanates. Alternatively, the secondary diamines may be reacted with organic diisocyanates in the absence of catalysts to form a urea diisocyanate which is then reacted in the presence of catalytic quantities of strong acids which form mixed carbamic acid anhydrides either with the same diisocyanate used in the first step or a second diisocyanate. The invention also relates to the polyisocyanates containing biuret and/or higher polyuret groups obtainable by this process.

Process for the preparation of polyisocyanates containing biuret and/or

The present invention relates to an improved process for the preparation of neopentyl glycol polyesters by reacting neopentyl glycol with carboxylic acids or derivatives thereof in the presence of minor amounts of glycols which boil at lower temperatures than neopentyl glycol. These low-boiling glycols obviate previous difficulties relating to the sublimation of neopentyl glycol. Thus, the present process offers safety advantages since neopentyl glycol does not crystallize in the reaction apparatus and also provides better control over the molecular ratio of acid groups to alcohol groups.

Process for the preparation of neopentyl glycol polyesters and

The instant invention is directed to a process for the production of elastic polyurethane foams capable of being flame laminated and high frequency welded, comprising reacting

Process for the manufacture of elastic polyurethane foams capable of

This invention relates to a new process for the production of organic polyisocyanates containing polyuret groups, to polyisocyanates obtainable by this process and to the use of the products obtained by the process as an isocyanate component in the production of polyurethane plastics.

Process for the production of modified polyisocyanates

The instant invention relates to an improved process for the continuous production of an aliphatic monoisocyanate from the corresponding N-alkyl carbamic acid aryl ester. More particularly, the invention is directed to a process for the continuous production of monoisocyanates corresponding to the formula R--NCO in which

Process for the continuous production of monoisocyanates

The present invention relates to a process for the preparation of allophanates containing aliphatically and/or cycloaliphatically bound isocyanate groups by the reaction of organic compounds containing urethane groups with organic polyisocyanates containing aliphatically and/or cycloaliphatically bound isocyanate groups, characterized in that the reaction is carried out in the presence of strong acids which form a mixed carbamic acid anhydride with aliphatic or cycloaliphatic isocyanates. The present invention also relates to the allophanates produced therefrom.

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Duesseldorf, Germany

Wolfgang Reichmann