Aqueous carbon black formulations for ink jet

Abstract

Finely divided solids are highly suitable for use as stabilizers for pyrocarbonic acid diesters, it being possible to use the mixtures obtained in this manner for preserving industrial materials and foodstuff.

1 . Use of at least one finely divided solid as additive for pyrocarbonic acid diesters for stabilizing them against chemical and/or thermal degradation reactions. 
   
   
       2 . Use according to  claim 1 , characterized in that the solid is an inorganic compound whose solubility in the pyrocarbonic acid diester at room temperature is less than 1 ppm. 
   
   
       3 . Use according to at least one of  claims 1  and  2 , characterized in that the solid has a particle size, determined by screening, in the range of ≦200 μm. 
   
   
       4 . Use according to at least one of  claims 1  to  3 , characterized in that the solid is a metal oxide, metal sulphide or a Lewis acid which is present in the solid state of aggregation at room temperature. 
   
   
       5 . Use according to at least one of  claims 1  to  4 , characterized in that the solid is
 (i) a metal oxide of the formula M 2 O, MO, M 2 O 3 , MO 2 , M 2 O 5 , MO 3 , M 2 O 7 , MO 4  or a double oxide of the formula M 3 O 4 ,
 where M is a metal ion or semimetal ion from the group of the first to fourth main group or the transition group or the lanthanoid group of the Periodic Table of the Elements, 
   (ii) a metal sulphide of the formula M 2 S, MS, M 2 S 3  or MS 2 ,
 where M is as defined above, 
 or 
   (iii) a Lewis acid from the group consisting of boric acid, metaboric acid, lanthanum triflate, ZrCl 4 , HfCl 4 , TaCl 5 , WCl 6 , NbCl 5  and YCl 3 .   
   
   
       6 . Use according to at least one of  claims 1  to  5 , characterized in that the dialkyl pyrocarbonates are compounds of the general formula 
     
       
         
         
             
             
         
       
     
     in which
 R 1  and R 2  independently of one another represent straight-chain or branched C 1 -C 8 -alkyl, cycloalkyl, C 2 -C 8 -alkenyl, C 2 -C 8 -alkynyl or benzyl which is in each case optionally mono- or polysubstituted by identical or different substituents from the group consisting of halogen, nitro, cyano, C 1 -C 6 -alkoxy, dialkylamino; or represent phenyl which is optionally mono- or polysubstituted by identical or different substituents from the group consisting of halogen, nitro, cyano, alkyl, haloalkyl, alkoxy, haloalkoxy, acyl, acyloxy, alkoxycarbonyl, carboxyl. 
 
   
   
       7 . Use according to at least one of  claims 1  to  6 , characterized in that the dialkyl pyrocarbonates are dimethylpyrocarbonates or diethyl pyrocarbonates. 
   
   
       8 . Use according to at least one of  claims 1  to  7 , characterized in that the solid or its mixture is employed in an amount of from 0.01 to 100 000 ppm, based on the dialkyl pyrocarbonate or its mixture. 
   
   
       9 . Use according to at least one of  claims 1  to  8 , characterized in that the stabilization is against degradation reactions during distillation or storage. 
   
   
       10 . Mixtures comprising one or more dialkyl pyrocarbonates of the general formula 
     
       
         
         
             
             
         
       
     
     in which
 R 1  and R 2  independently of one another represent straight-chain or branched C 1 -C 8 -alkyl, cycloalkyl, C 2 -C 8 -alkenyl, C 2 -C 8 -alkynyl or benzyl which is in each case optionally mono- or polysubstituted by identical or different substituents from the group consisting of halogen, nitro, cyano, C 1 -C 6 -alkoxy, dialkylamino; or represent phenyl which is optionally mono- or polysubstituted by identical or different substituents from the group consisting of halogen, nitro, cyano, alkyl, haloalkyl, alkoxy, haloalkoxy, acyl, acyloxy, alkoxycarbonyl, carboxyl, 
 
     and one or more finely divided solids in an amount of from 0.01 to 100 000 ppm, based on the dialkyl pyrocarbonate or its mixtures. 
   
   
       11 . Mixture according to  claim 10 , characterized in that the solids are inorganic compounds whose solubility in the pyrocarbonic acid diester or its mixture at room temperature is less than 1 ppm. 
   
   
       12 . Mixture according to at least one of  claims 10  and  11 , characterized in that the solids have a particle size, determined by screening, in the range of ≦200 μm. 
   
   
       13 . Mixture according to at least one of  claims 10  to  12 , characterized in that the solids are
 (i) metal oxides of the formula M 2 O, MO, M 2 O 3 , MO 2 , M 2 O 5 , MO 3 , M 2 O 7 , MO 4  or double oxides of the formula M 3 O 4 ,
 where M is a metal ion or semimetal ion from the group of the first to fourth main group or the transition group or the lanthanoid group of the Periodic Table of the Elements, 
   (ii) metal sulphides of the formula M 2 S, MS, M 2 S 3  or MS 2 ,   where M is as defined above,   or   (iii) Lewis acids from the group consisting of boric acid, metaboric acid, lanthanum triflate, ZrCl 4 , HfCl 4 , TaCl 5 , WCl 6 , NbCl 5  and YCl 3 .   
   
   
       14 . Mixture according to at least one of  claims 10  to  13 , characterized in that they comprise at least one compound from the group consisting of dimethylpyrocarbonate and diethyl pyrocarbonate and B 2 O 3  having a particle size, determined by screening, of ≦32 μm. 
   
   
       15 . Use of a mixture according to at least one of  claims 10  to  14  for protecting and preserving industrial materials, foodstuff and beverages. 
   
   
       16 . Process for the distillative purification of dialkyl pyrocarbonates, characterized in that one or more dialkyl pyrocarbonates of the general formula 
     
       
         
         
             
             
         
       
     
     in which
 R 1  and R 2  independently of one another represent straight-chain or branched C 1 -C 8 -alkyl, cycloalkyl, C 2 -C 8 -alkenyl, C 2 -C 8 -alkynyl or benzyl which is in each case optionally mono- or polysubstituted by identical or different substituents from the group consisting of halogen, nitro, cyano, C 1 -C 6 -alkoxy, dialkylamino; or represent phenyl which is optionally mono- or polysubstituted by identical or different substituents from the group consisting of halogen, nitro, cyano, alkyl, haloalkyl, alkoxy, haloalkoxy, acyl, acyloxy, alkoxycarbonyl, carboxyl, is/are admixed with one or more finely divided solids in an amount of from 0.01 to 100 000 ppm, based on the dialkyl pyrocarbonate or its mixture, and the mixture is then distilled at a pressure of from 5 to 100 mbar and a temperature between 30 and 120° C. 
 
   
   
       17 . Process according to  claim 16 , characterized in that the solids are
 (i) metal oxides of the formula M 2 O, MO, M 2 O 3 , MO 2 , M 2 O 5 , MO 3 , M 2 O 7 , MO 4  or double oxides of the formula M 3 O 4 ,   where M is a metal ion or semimetal ion from the group of the first to fourth main group or the transition group or the lanthanoid group of the Periodic Table of the Elements,   (ii) metal sulphides of the formula M 2 S, MS, M 2 S 3  or MS 2 ,   where M is as defined above,   or   (iii) Lewis acids from the group consisting of boric acid, metaboric acid, lanthanum triflate, ZrCl 4 , HfCl 4 , TaCl 5 , WCl 6 , NbCl 5  and YCl 3      
     which have a particle size, determined by screening, in the range of ≦200 μm.