Extrusion

Abstract

The invention relates to a process for preparing a controlled release pharmaceutical extrudate using a melt extruder, wherein the melt extruder comprises a die-head supporting a die-plate in which orifices are located, and a cutter adjacent to the die-head, and wherein the cutter cuts the extruded mix as it emerges under pressure and still molten or softened from the orifices of the die-plate.

1 . A process for preparing a controlled release pharmaceutical extrudate using a melt extruder, 
 wherein the melt extruder comprises a die-head supporting a die-plate in which orifices are located,    and a cutter adjacent to the die-head,    and wherein the cutter cuts the extruded mix as it emerges under pressure and still molten or softened from the orifices of the die-plate    
     
     
         2 . A process according to  claim 1 , wherein the cutter is a rotary cutter with two diametrically opposed blades.  
     
     
         3 . A process according to  claim 1 , wherein a stream of air of reduced temperature is directed into the region of the surface of the die-head during cutting.  
     
     
         4 . A process for preparing a controlled release pharmaceutical extrudate with rounded surfaces, which process comprises providing a melt extruder comprising a die-head supporting a die-plate in which orifices are located, 
 and a cutter adjacent to the die-head,    feeding the mix through the extruder,    cutting the extruded mix as it emerges under pressure and still molten or softened from the orifices of the die-plate,    and adjusting the rate of extrusion and the speed of the cutter blade to give generally cylindrical multiparticulates,    spherical or substantially spherical, ellipsoidal or disc shaped multiparticulates.    
     
     
         5 . A process according to  claim 4 , wherein the multiparticulates are spherical or substantially spherical.  
     
     
         6 . Melt extruded multiparticulates having rounded surfaces obtainable by the process of  claim 4 .  
     
     
         7 . Melt extruded multiparticulates according to  claim 6 , which are generally cylindrical, spherical or substantially spherical, ellipsoidal or disc shaped.