PETAL-LIKE POROUS BASE FOR SUSTAINED RELEASE BODY AND SUSTAINED RELEASE BODY COMPOSITION

摘要

PROBLEM TO BE SOLVED: To obtain the subject base useful as a carrier capable of controlling the sustained release depending upon kinds of use and medicine, by using specific particles. SOLUTION: This base comprises a calcium phosphate-based compound having a petal-like porous structure composed of calcium carbonate as a nucleus material, has an atomic ratio of Ca/P of =16.7 and satisfies the equations 0.2=dx1 =20(m), 0.01=dx2 =1(m), 50=Sw1 =500(m2 g), 95=1=99, 70=2=95, 1==5 with the proviso that =d50 /dx1 , 0==2 with the proviso that =(d90 -d10 )/d50 [dx1 is an average particle diameter; d2 is an average pore diameter; Sw1 is a BET specific surface area (m2 /g); 1 is a stationary porosity (%) obtained by measurement of an apparent specific volume (mL/g) and calculated by formula I,; 2 is a pressure porosity (%) under 30kg/cm2 pressure obtained by packing a specimen to a cylinder, pressurizing, measuring the thickness and calculating an equation of formula II; is dispersion coefficient; d50 is 50% average particle diameter of particle; is sharpness D90 and d10 are particle diameter of 90% and 10% of the total of sieve passing side].