| abstract |
A process for preparing a glass or glass-ceramic composite sintered body by a sol-gel method comprises reacting (A) at least one silicic acid ester represented by the general formula (I). <IMAGE> [I] wherein R1 to R4 are each hydrogen or a group represented by Chd xH2x+1(OC2H4)y- wherein x is 1 to 5, and y is 0 to 10, provided that R1 to R4 are not all hydrogen at the same time, and n is 0 to 20; (B) at least one phosphorus compound represented by the general formula (II), (III) or (IV): <IMAGE> [II] <IMAGE> [III] <IMAGE> wherein R5 to R9 are each hydrogen, an alkyl group having 1 to 5 carbon atoms, a phenyl group or an aralkyl group having 7 to 10 carbon atoms, and m is 0 to 10; and (C) at least one compound selected from the group consisiting of calcium salts and calcium coumpounds represented by the general formula (V) Ca(OR10)2 (V) wherein R10 represents an alkyl group having 1 to 5 carbon atoms; with water in the presence of the follwing componentn (D-1) and/or the following component (D-2) to form a gel, and drying, molding and then sintering the gel; (D-1): at least one kind of ceramics fine particles having a composition different from a sintered body obtained form components (A) to (C) or having a crystal different from crystals formed in the sintered body, (D-2): ceramic short fibers and/or whiskers. SiO2-P2O5-CaO glass or glass-ceramic composite sintered body contains at least one of ceramics short fibers and/or whiskers, and at least one of ceramics fine particles. According to the invention, there can be obtained composite sintered bodies of calcium phosphate glasses or glass-ceramics exhibiting excellent in biocompatibility in which ceramics fine particles, ceramics fibers and whiskers are uniformly dispersed and mixed, and strength, toughness and scatter of strength are effectively improved. Thus the composite sintered bodies of the invention are widely applicable as materials for hard tissue of living bodies such as artificial tooth roots and artificial bones. |