Filter element with coating for surface filtration

Abstract

An inherently stable, flow-porous filter element ( 2 ) having a porous coating ( 10 ) for surface filtration on its afflux surface, said coating ( 10 ) comprising: (a) a main component of particles ( 12 ) and/or fibers ( 22 ); (b) an inorganic binder component ( 14; 24 ) binding the particles ( 12 ) and/or the fibers ( 22 ) of the main component to each other; (c) an adhesive ( 16; 26 ) binding the porous coating ( 10 ) to the remainder of the filter element; (d) and an anti-adhesion component ( 18; 28 ) mitigating the adhesion of filtered out material to the porous coating and facilitating cleaning of the filter element.

1 . An inherently stable, flow-porous filter element ( 2 ) having a porous coating ( 10 ) for surface filtration on its afflux surface, said coating ( 10 ) comprising: 
 (a) a main component of particles ( 12 ) and/or fibers ( 22 );    (b) an inorganic binder component ( 14 ;  24 ) binding the particles ( 12 ) and/or the fibers ( 22 ) of the main component to each other;    (c) an adhesive ( 16 ;  26 ) binding the porous coating ( 10 ) to the remainder of the filter element; and    (d) an anti-adhesion component ( 18 ;  28 ) mitigating the adhesion of filtered out material to the porous coating and facilitating cleaning of the filter element.    
   
   
       2 . A filter element according to  claim 1 , characterized in that the main component comprises one material of the group consisting of kieselguhr particles ( 12 ), zeolite particles, polyvinyl pyrrolidone particles and mixtures thereof.  
   
   
       3 . A filter element according to  claim 2 , characterized in that the main component comprises kieselguhr particles ( 12 ).  
   
   
       4 . A filter element according to  claim 1 , characterized in that the main component comprises ceramic fibers ( 22 ).  
   
   
       5 . A filter element according to  claim 1 , characterized in that the binder component comprises one material of the group consisting of crosslinked SiO 2  ( 14 ;  24 ), crosslinked SiO 2  derivative, crosslinked TiO 2  derivative, crosslinked ZrO 2 , crosslinked ZrO 2  derivative and mixtures thereof.  
   
   
       6 . A filter element according to  claim 5 , characterized in that the binder component comprises crosslinked SiO 2  ( 14 ;  24 ).  
   
   
       7 . A filter element according to  claim 1 , characterized in that the adhesive is an organic dispersion adhesive ( 16 ;  26 ).  
   
   
       8 . A filter element according to  claim 1 , characterized in that the anti-adhesion component is polytetrafluorothylene (PTFE) ( 18 ;  28 ) and/or silicone.  
   
   
       9 . A filter element according to  claim 1 , characterized in that the coating ( 10 ) is applied in accordance with the sol-gel process.  
   
   
       10 . A filter element according to  claim 1 , characterized in that the coating ( 10 ) contains kieselguhr ( 12 ) as main component and PTFE ( 18 ;  28 ) as anti-adhesion component in a weight ratio of 1:1 to 1:2.  
   
   
       11 . A filter element according to  claim 1 , characterized in that the main body of the filter element ( 2 ) is composed of sintered plastics particles ( 4 ).  
   
   
       12 . The use of the filter element according to  claim 1 , comprising particles ( 12 ) as main component of the coating ( 10 ), for liquid filtration or for oil mist separation.  
   
   
       13 . The use according to  claim 12  for filtration of cooling lubricant.  
   
   
       14 . The use according to  claim 12 , wherein foreign particles of a size of more than 5 μm are filtered out in essence completely.  
   
   
       15 . The use of the filter element according to  claim 1 , comprising fibers ( 22 ) as main component of the coating ( 10 ), for gas filtration.  
   
   
       16 . The use according to  claim 15 , wherein foreign particles of a size of more than 2 μm are filtered out in essence completely.