치아 연마용 인산일수소칼슘의 합성 및 물리화학적 성질 = Synthesis and Physico-Chemical Properties of Dicalcium Phosphate Dihydrate for Dental Abrasive

다국어 초록 (Multilingual Abstract)

Dental abrasive, dicalcium phosphate dihydrate (DCPD) was prepared and the several important factors affecting on the quality of toothpaste were investigated by means of set test, glycerine absorption, Coulter counter test, color difference, BET adsorption, mercury porosimetery, and rheogram comparing with two foreign DCPDs, MFO4 and Dentphos K. Sample DCPD was prepared by reaction between 85% H_3PO_4 and 15% milk of lime at 39℃ (pH 6.5), and stabilized with TSPP and TMP. The physicochemical properties of Sample DCPD were obtained as follows: whiteness (98.99), average particle size (15.5㎛), pH(7.9), remainder particle weight (0.49 w/w%), glycerine absorption value (64㎖), and set test (passed). N_2 adsorption curves (BET) of three kinds of DCPD showed non-porous type Ⅲ isotherm. BET adsorption parameters of sample DCPD showed that surface area was 24.9 ㎡/g, total pore volume 0.09 ㎤/g and average pore radius 72.0Å. The rheogram of the toothpaste containing each DCPD showed bulged plastic flow with yield value and thixotropic behavior. These results meet standard requirements as abrasive standard, and suggested that synthesized sample DCPD could be used a dental abrasive such as a high quality grade in practice as foreign DCPDs.