[15p-D305-1~13] 1.6 Ultrasonics

△ [15p-D305-8] Effect of number concentration on microcapsule disruption under ultrasound irradiation

〇Naohiro Sugita¹, Tadahiko Shinshi¹ (1.Tokyo Tech FIRST)

Keywords:ultrasound, microcapsule

Size and spatial distributions of disrupted microcapsules under ultrasound irradiation are optically observed, and the disruption rate is experimentally obtained as a function of the number concentration of the capsules. Microcapsules confined in a 2D observation chamber are sonicated by a sinusoidal burst ultrasound with a frequency of 1 MHz. We defined the concentration as the number of the capsules in a unit area of the planar chamber, which is calculated using image analysis of the recorded microscopic images. It found that the maximum disruption rate is achieved with a moderate concentration; a higher concentration gives rise to deterioration of the disruption rate because of the mutual interaction between the microcapsules.