Aqueous dispersion of water-insoluble organic UV filter substances

Abstract

The invention relates to aqueous dispersions of sparingly water-soluble or water-insoluble organic UV filter substances, which comprise at least one sparingly water-soluble or water-insoluble organic UV filter substance as colloidally disperse phase in amorphous or partially amorphous form.

We claim:  
     
         1 . An aqueous dispersion of sparingly water-soluble or water-insoluble organic UV filter substances, which comprises at least one sparingly water-soluble or water-insoluble organic UV filter substance as colloidally disperse phase in amorphous or partially amorphous form.  
     
     
         2 . An aqueous dispersion as claimed in  claim 1 , which is a suspension which comprises at least one sparingly water-soluble or water-insoluble organic UV filter substance as nanoparticulate particles in amorphous or partially amorphous form.  
     
     
         3 . An aqueous dispersion as claimed in  claim 1 , wherein the particles of the colloidally disperse phase have a core and a shell, where the core comprises at least one sparingly water-soluble or water-insoluble organic UV filter substance, and the shell comprises at least one protective colloid.  
     
     
         4 . An aqueous dispersion as claimed in any of  claims 1  to  3 , wherein the particles of the colloidally disperse phase have a mean particle size of less than 10 μm.  
     
     
         5 . An aqueous dispersion as claimed in any of  claims 1  to  4 , comprising 0.1 to 70% by weight of at least one sparingly water-soluble or water-insoluble organic UV filter subtance, 0.1 to 80% by weight of at least one polymeric protective colloid, all of the percentages being based on the dry mass of the aqueous dispersion.  
     
     
         6 . An aqueous dispersion as claimed in  claim 5 , additionally comprising 0.1 to 70% by weight of at least one softener, 0.01 to 70% by weight of at least one emulsifier and/or 0.01 to 50% by weight of at least one antioxidant and/or preservative.  
     
     
         7 . An aqueous dispersion as claimed in  claim 1 , wherein the particles of the colloidally disperse phase comprise a water-insoluble polymer matrix into which at least one sparingly water-soluble or water-insoluble organic UV filter substance has been embedded.  
     
     
         8 . An aqueous dispersion as claimed in  claim 7 , wherein the colloidally disperse particles have additionally been coated by a protective colloid.  
     
     
         9 . An aqueous dispersion as claimed in  claim 7 , comprising 0.1 to 70% by weight of at least one sparingly water-soluble or water-insoluble organic UV filter substance, 0.1 to 80% by weight of at least one water-insoluble matrix polymer and 0 to 80% by weight of at least one polymeric protective colloid, all of the percentages being based on the dry mass of the aqueous dispersion.  
     
     
         10 . An aqueous dispersion as claimed in  claim 9 , additionally comprising 0.1 to 70% by weight of at least one softener, 0.01 to 70% by weight of at least one emulsifier and/or 0.01 to 50% by weight of at least one antioxidant.  
     
     
         11 . An aqueous dispersion as claimed in any of  claims 1  to  10 , comprising at least one 1,3,5-triazine derivative of the formula I  
       
         
           
           
               
               
           
         
       
       in which the substituents independently of one another have the following meanings: 
 R is hydrogen, halogen, OH, C 1 -C 20 -alkyl, C 1 -C 20 -alkoxy, C 1 -C 20 -alkoxyalkyl, C 1 -C 20 -hydroxyalkoxy, NR 1 R 2 , 
 or a radical of the formula Ia  
                     
 
 R 1  and R 2  
 are hydrogen, C 1 -C 20 -alkyl, C 6 -C 12 -aryl optionally substituted by one or more C 1 -C 4 -alkyl, C 7 -C 10 -aralkyl optionally substituted by one or more C 1 -C 4 -alkyl, heteroaryl optionally substituted by one or more C 1 -C 4 -alkyl, C 5 -C 8 -cycloalkyl;  
 
 R 3  to R 5  
 are hydrogen, OH, NR 9 R 10 , C 1 -C 20 -alkoxy, C 6 -C 12 -aryl optionally substituted by one or more C 1 -C 4 -alkyl, C 7 -C 10 -aralkyl optionally substituted by one or more C 1 -C 4 -alkyl, heteroaryl optionally substituted by one or more C 1 -C 4 -alkyl, C 5 -C 8 -cycloalkyl;  
 
 R 6  to R 8  
 are hydrogen, C 1 -C 20 -alkoxy, —C(═O)—R 11 , —(═O)—X—R 12 , SO 2 R 13 , CN;  
 
 R 9  to R 11  
 are hydrogen, C 1 -C 20 -alkyl, C 6 -C 12 -aryl optionally substituted by one or more C 1 -C 4 -alkyl, C 7 -C 10 -aralkyl optionally substituted by one or more C 1 -C 4 -alkyl, heteroaryl optionally substituted by one or more C 1 -C 4 -alkyl, C 5 -C 8 -cycloalkyl;  
 
 R 12  is hydrogen, C 1 -C 20 -alkyl, C 6 -C 12 -aryl optionally substituted by one or more C 1 -C 4 -alkyl, C 7 -C 10 -aralkyl optionally substituted by one or more C 1 -C 4 -alkyl, heteroaryl optionally substituted by one or more C 1 -C 4 -alkyl, C 5 -C 8 -cycloalkyl or a radical of the formula Sp-Sil;  
 R 13  is C 1 -C 20 -alkyl, C 5 -C 8 -cycloalkyl, C 6 -C 12 -aryl optionally substituted by one or more C 1 -C 4 -alkyl, C 7 -C 10 -aralkyl optionally substituted by one or more C 1 -C 4 -alkyl, heteroaryl optionally substituted by one or more C 1 -C 4 -alkyl;  
 X is O, NR 14 ;  
 R 14  is hydrogen, C 1 -C 20 -alkyl, C 6 -C 12 -aryl optionally substituted by one or more C 1 -C 4 -alkyl, C 7 -C 10 -aralkyl optionally substituted by one or more C 1 -C 4 -alkyl, heteroaryl optionally substituted by one or more C 1 -C 4 -alkyl, C 5 -C 8 -cycloalkyl;  
 Sp is a spacer;  
 Sil is a radical from the group consisting of silanes, oligosiloxanes and polysiloxanes.  
 
     
     
         12 . An aqueous dispersion as claimed in  claim 11 , comprising at least one 1,3,5-triazine derivative of the formula Ib in which the substituents, independently of one another, have the following meanings:  
       
         
           
           
               
               
           
         
         R 3  to R 5  
 are hydrogen, OH;  
 
         R 6  to R 8  
 are C 1 -C 12 -alkoxy, —C(═O)—X—R 12 ;  
 
         X is O, NR 14 ;  
         R 12  and R 14  
 are hydrogen, C 4 -C 8 -alkyl.  
 
       
     
     
         13 . An aqueous dispersion as claimed in any of  claims 1  to  10 , comprising at least one triazole of the formula IIIb,  
       
         
           
           
               
               
           
         
       
       in which T 6  and T 7  independently of one another are C 1 -C 18 -alkyl.  
     
     
         14 . An aqueous dispersion as claimed in  claim 13 , comprising at least one triazole derivative of the formula IlIb, in which T 6  and T 7  independently of one another are tert-butyl, —C(CH 3 ) 2 —CH 2 —C(CH 3 ) 3  or 2-ethylhexyl.  
     
     
         15 . A process for the preparation of an aqueous dispersion of at least one sparingly water-soluble or water-insoluble organic UV filter substance, defined as in  claim 1 , which comprises 
 a) preparing a molecularly disperse solution of at least one sparingly water-soluble or water-insoluble organic UV filter substance in an organic solvent,    b) treating this solution with an aqueous solution of at least one protective colloid, the hydrophobic phase of the UV filter substance forming as colloidally disperse phase, and    c) freeing the resulting dispersion from the organic solvent.    
     
     
         16 . A process as claimed in  claim 15 , wherein the organic solvent used in process step a) is at least one water-miscible, organic solvent or a mixture of water and at least one water-miscible organic solvent.  
     
     
         17 . A process as claimed in either of claims  15  or  16 , wherein further additives, chosen from the group consisting of emulsifiers, antioxidants, preservatives, water-insoluble polymers and cosmetic oils are added to the molecularly disperse solution in step a).  
     
     
         18 . A process as claimed in any of  claims 15  to  17 , wherein, in step b), the aqueous protective colloid solution additionally comprises at least one softener.  
     
     
         19 . A process as claimed in any of  claims 15  to  18 , wherein, in step a), the molecularly disperse solution of at least one sparingly water-soluble or water-insoluble organic UV filter substance is prepared at temperatures greater than 15° C., and immediately thereafter, is treated in step b) with the aqueous solution of the protective colloid, a mixing temperature of from 35° C. to 120° C. being established.  
     
     
         20 . A process for the preparation of an aqueous dispersion of at least one sparingly water-soluble or water-insoluble organic UV filter substance, defined as in  claim 7 , which comprises 
 a) preparing a molecularly disperse solution of at least one sparingly water-soluble or water-insoluble organic UV filter substance and a water-insoluble polymer in an organic solvent,    b) treating this solution with water or an aqueous solution of at least one protective colloid, the hydrophobic phase of the mixture comprising UV filter substance and water-insoluble polymer forming as colloidally disperse phase, and    c) freeing the resulting dispersion from the organic solvent.    
     
     
         21 . A process as claimed in  claim 20 , wherein, in step b), an aqueous protective colloid solution is used.  
     
     
         22 . A process for the preparation of a dry powder comprising at least one sparingly water-soluble or water-insoluble organic UV filter substance as nanoparticular particles in amorphous or partially amorphous form, which comprises freeing an aqueous dispersion defined as in  claim 1  from the water and drying it, optionally in the presence of a coating material.  
     
     
         23 . A pulverulent preparation of at least one sparingly water-soluble or water-insoluble organic filter substance obtainable by a process defined as in  claim 22 , comprising at least one sparingly water-soluble or water-insoluble organic UV filter substance as nanoparticular particles in amorphous or partially amorphous form.  
     
     
         24 . A process for the preparation of an oil-miscible preparation of at least one sparingly water-soluble or water-insoluble organic UV filter substance in the form of a double dispersion, which comprises emulsifying an aqueous dispersion defined as in  claim 1  in the presence of an emulsifier in oil.  
     
     
         25 . A liquid, oil-miscible preparation of at least one sparingly water-soluble or water-insoluble organic UV filter substance obtainable by a process defined as in  claim 24 , which, as a double dispersion system, comprises an aqueous-disperse phase having a particle diameter of less than 500 μm, in which protective-colloid-stabilized particles of one or more sparingly water-soluble or water-insoluble organic UV filter substances are present in dispersed form, in an oil as dispersant.  
     
     
         26 . The use of the aqueous dispersion defined as in any of  claims 1  to  14  as a photostable light protection agent for organic materials.  
     
     
         27 . The use of the pulverulent preparation defined as in  claim 23  as a photostable light protection agent for organic materials.  
     
     
         28 . The use of the liquid, oil-miscible preparation defined as in  claim 25  as a photostable light protection agent for organic materials.  
     
     
         29 . The use as claimed in any of  claims 26  to  28  as stabilizer for plastics and coating materials.  
     
     
         30 . The use as claimed in any of  claims 26  to  28  as a photostable UV filter in cosmetic and pharmaceutical preparations for protecting human skin or human hair from UV rays.  
     
     
         31 . The use as claimed in any of  claims 26  to  28  as a UV stabilizer in cosmetic and pharmaceutical preparations.  
     
     
         32 . A cosmetic or pharmaceutical preparation comprising a light protection agent for protecting the human skin or human hair from UV light in the range from 280 to 400 nm, which comprises, as photostable UV filter, an effective amount of an aqueous dispersion defined as in  claim 1  in a cosmetically or pharmaceutically suitable carrier.  
     
     
         33 . A cosmetic or pharmaceutical preparation comprising a light protection agent for protecting the human skin or human hair from UV light in the range from 280 to 400 nm, which comprises, as photostable UV filter, an effective amount of a pulverulent preparation defined as in  claim 23  in a cosmetically or pharmaceutically suitable carrier.  
     
     
         34 . A cosmetic or pharmaceutical preparation comprising a light protection agent for the protection of human skin or human hair against UV light in the range from 280 to 400 nm, which comprises, as photostable UV filter, an effective amount of a liquid, oil-miscible preparation defined as in  claim 25  in a cosmetically or pharmaceutically suitable carrier.