Stabilized preparations of aromatic isocyanatosulphonic acids
AssigneeBayer Aktiengesellschaft
InventorDieter Dieterich
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Abstract
The present invention relates to a process for increasing the storage stability of solid aromatic isocyanatosulphonic acids by the addition of a substantially apolar, stabilizing agent which is inert towards isocyanate groups and sulphonic acid groups, which has a melting point in the region between about 27.degree. and 250.degree. C. and which, in the molten state, is a non-solvent for the isocyanatosulphonic acids. The present invention also relates to mixtures which are stable in storage and which may be in the form of a moist powder or a paste containing a mixture of solid, finely dispersed, aromatic isocyanatosulphonic acid and the substantially apolar, inert stabilizing agent mentioned above.
Claims10
A process for increasing the stability in storage of finely dispersed solid aromatic isocyanatosulphonic acids obtained by the sulphonation of aromatic isocyanates comprising sulphonating the aromatic isocyanate in the presence of a liquid which is inert towards isocyanate groups and sulphonic acid groups, which is a non-solvent for the aromatic isocyanatosulphonic acids and which is either
- (a) a melt of a solid stabilizing agent which is inert towards isocyanate groups and sulphonic acid groups and which has a melting point above about 26.degree. C. or
- (b) at least a 10% by weight solution of the solid stabilizing agent of (a) in a solvent which is inert towards isocyanatosulphonic acids,
- characterized in that said solid stabilizing agent remains in the sulphonation product after termination of the sulphonation reaction in an amount between about 5% and 60% by weight, based on the weight of the sulphonation product.
A process for increasing the stability in storage of finely dispersed solid aromatic isocyanatosulphonic acids obtained by the sulphonation of aromatic isocyanates comprising mixing a solid, finely dispersed aromatic isocyanatosulphonic acid with a liquid which is inert towards isocyanate groups and sulphonic acid groups, which is a non-solvent for the aromatic isocyanatosulphonic acid and which is either
- (a) a melt of a solid, stabilizing agent which is inert towards isocyanate groups and sulphonic acid groups and which has a melting point above about 26.degree. C. or
- (b) at least a 10% by weight solution of said solid stabilizing agent in a solvent which is inert towards isocyanatosulphonic acids,
- characterized in that said solid stabilizing agent is present in the resultant mixture in an amount between about 5% and 60% by weight, based on the weight of the mixture.
A process for increasing the stability in storage of finely dispersed solid aromatic isocyanatosulphonic acids obtained by sulphonation of aromatic isocyanates, characterized in that
- (a) sulphonation of the aromatic isocyanates is carried out in the presence of an inert liquid which is a non-solvent for the aromatic isocyanatosulphonic acids and which is either a melt of an inert solid which melts about 26.degree. C. or an at least 10% by weight solution of such a solid in an inert solvent, characterized in that said solid is at least partly left in the sulphonation product after termination of the sulphonation reaction, or
- (b) solid, finely dispersed aromatic isocyanatosulphonic acids prepared in the absence of a liquid of the type defined under (a) are mixed with such a liquid.
A storage stable mixture comprising
- (a) about 40-95% by weight of solid, finely dispersed, aromatic isocyanatosulphonic acids and
- (b) about 60-5% by weight of a solid stabilizing agent which is inert towards isocyanate groups and sulphonic acid groups and has a melting point between about 27.degree. and 250.degree. C.,
- characterized in that the solid stabilizing agent completely envelops the particles of the finely dispersed isocyanatosulphonic acids.
A mixture which is stable in storage and which is optionally in the form of a moist powder or paste, containing
- (a) about 40-95% by weight of solid, finely dispersed, aromatic isocyanatosulphonic acids and
- (b) about 60-5% by weight of a substantially apolar solid substance which is inert towards isocyanate groups and sulphonic acid groups, has a melting point in the region of from about 27.degree. to 250.degree. C. and is a non-solvent for the aromatic isocyanatosulphonic acid mentioned under (a), characterized in that
- the solid substance mentioned under (b), optionally dissolved in inert liquids, envelops the particles of the finely dispersed isocyanatosulphonic acids.
Dependencies are inferred from the claim text.