초임계이산화탄소와 초임계수와 같은 초임계유체의 환경친화적 성질은 미세입자를 제조하는 새로운 재료분야의 응용에 많은 관심의 대상이 되고 있다. 최근에는 초임계유체의 저독성과 불연성 그리고 저렴한 가격 때문에 의약품, 화장품, 세라믹, 식품 그리고 폭약 등에서 이를 이용하여 나노 또는 마이크로입자를 제조하는 공정에 많은 이용되고 있다. 본고에서는 초임계유체를 이용하여 미세입자를 제조하는 대표적인 공정인 RESS(rapid expansion of supercritical solutions), SAS(supercriticalanti solvent) 그리고 PGSS(particles from gas saturated solutions)등에 대하여 중점적으로 소개하고자 한다.

The environmentally friendly nature of supercritical fluids such as supercritical carbon dioxide and supercritical water has led to the exploration of their use in a range of materials applications. In the last few years, several supercritical fluids-based techniques have been proposed for the production of micronic and nanometric particles for potential applications in areas such as pharmaceuticals, cosmetics, inorganics, biomaterials and explosives. Techniques like the rapid expansion of supercritical solutions (RESS), supercritical antisolvent precipitation (SAS), particle generation from gas-saturated solutions (PGSS), and reactive precipitation in supercritical solutions (RPSS) have been critically reviewed.

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