抄録
Porous calcium phosphate film could be formed on a TiO2 substrate by a spray-pyrolysis technique. The aqueous solutions containing 1.0 mol· dm-3 Ca (NO3) 2 100 cm3, 0.6 mol· dm-3 (NH4) 2 HPO4 100 cm3 and conc. HNO3 6 cm3 were spray-pyrolysed at 600°C for 5, 10 and 15 h, respectively, to form calcium-phosphate layers on TiO2 substrate; TiO2 substrate coated with calcium-phosphate layers was heat-treated at a temperature between 1000°C and 1300°C. The calcium-phosphate film (thickness, -35 μm) containing pores with sizes of -50 μm was formed on TiO2 substrate under the following conditions : the spray-pyrolysis : 600°C and 10 h and the heat-treatment : 1250°C and 5 h. The calcium-phosphate film was bonded to TiO2 substrate through the reaction layers of CaTi4O9 and amorphous materials in the CaO-P2O5-TiO2 system. The surface layer of the film contained chiefly β-Ca3 (PO4) 2, whereas the bulk contained a-Ca3 (PO4) 2.
