MICROFILTER - Micropore Polyester Filters for Upgrading Industrial Water Quality A membrane filter used for removing microscopic organisms and particles from liquids and gases, MICROFILTER is widely used by the pharmaceutical and semiconductor industries for high-tech processes that require ultrapure water and by brewers for microfiltering beer and rice wine. Besides MICROFILTER, Fujifilm has used its unique membrane manufacturing technologies to develop numerous other products, including PT FILM polyester films for printing, laminating, and platemaking applications as well as OHP film products for use with copiers and heat-transfer printers.