Porous sintered body of calcium phosphate-based ceramic and method for producing same

Abstract

A porous sintered body of a calcium phosphate-based ceramic having a porosity of 80% or more. The porous sintered body is produced by a method comprising the steps of: (1) preparing a slurry comprising a calcium phosphate-based ceramic powder, a water-soluble high molecular compound and a nonionic surface active agent; (2) stirring the slurry vigorously to froth the slurry; (3) solidifying the frothed slurry into a gel; and (4) drying and sintering the gel.

What is claimed is:  
     
         1 . A porous sintered body of a calcium phosphate-based ceramic having a porosity of 80% or more.  
     
     
         2 . The porous sintered body according to  claim 1 , wherein said porous sintered body has an average pore-diameter of 5 to 1500 μm.  
     
     
         3 . The porous sintered body according to  claim 1 , wherein a weight ratio of Ca/P in said calcium phosphate-based ceramic is 1.6 to 1.7.  
     
     
         4 . The porous sintered body according to  claim 1 , wherein said calcium phosphate-based ceramic is hydroxyapatite.  
     
     
         5 . A method for producing a porous sintered body of a calcium phosphate-based ceramic having a porosity of 80% or more, wherein said method comprises the steps of: (1) preparing a slurry comprising a calcium phosphate-based ceramic powder, a water-soluble high molecular compound and a nonionic surface active agent; (2) stirring said slurry vigorously to froth said slurry; (3) solidifying the frothed slurry into a gel; and (4) drying and sintering said gel.  
     
     
         6 . The method for producing a porous sintered body according to  claim 5 , wherein said calcium phosphate-based ceramic powder is a secondary particle having an average particle diameter of 0.5 to 80 μm prepared from a primary particle having an average particle diameter of 100 nm or less.  
     
     
         7 . The method for producing a porous sintered body according to  claim 5 , wherein said water-soluble high molecular compound is a cellulose derivative.  
     
     
         8 . The method for producing a porous sintered body according to  claim 5 , wherein said nonionic surface active agent is a fatty acid alkanolamide surface active agent.  
     
     
         9 . The method for producing a porous sintered body according to  claim 5 , wherein 1 to 10 part by weight of said water-soluble high molecular compound and 1 to 10 part by weight of said nonionic surface active agent are used with 100 parts by weight of said calcium phosphate-based ceramic powder.  
     
     
         10 . The method for producing a porous sintered body according to  claim 5 , wherein a weight ratio of the total of said calcium phosphate-based ceramic powder, said water-soluble high molecular compound and said nonionic surface active agent is 20 to 50 weight % based on 100 weight % of said slurry.  
     
     
         11 . The method for producing a porous sintered body according to  claim 5 , wherein said slurry is stirred under a stirring condition of 50 W/L or more to froth said slurry.  
     
     
         12 . The method for producing a porous sintered body according to  claim 5 , wherein said slurry is stirred at 5 to 20° C. to froth said slurry.  
     
     
         13 . The method for producing a porous sintered body according to  claim 5 , wherein said nonionic surface active agent is free of a metal ion and a sulfate group.  
     
     
         14 . The method for producing a porous sintered body according to  claim 5 , wherein said slurry is stirred while passing a gas through said slurry to froth said slurry.  
     
     
         15 . The method for producing a porous sintered body according to  claim 5 , wherein said calcium phosphate-based ceramic is hydroxyapatite.