Korean researchers have developed a face mask with a nano-fiber filter that can be used repeatedly after washing and disinfection.
The Korea Advanced Institute of Science and Technology (KAIST) announced on March 16 that Prof. Kim Il-doo of the Department of New Materials Engineering has developed a nano-fiber membrane for masks that maintains excellent filter efficiency even after being washed.
The nano-fiber mask maintained initial filtration efficiency of 94 percent or higher even after being repeatedly washed 20 times in an ethanol sterilization and wash test.
In addition, the team explained that even if the mask was soaked in ethanol for more than 3 hours, its nano-fiber did not melt or its membrane was not warped, so it could be used for more than one month even after sterilization and washing with ethanol.
Founded in February last year, the Kim Il-doo Research Institute, a company founded by the KAIST professor, has built a nano-fiber membrane mass production facility. The company can produce 7 meters of the membrane per hour, a volume enough to produce an average of 1,500 nano-fiber mask filters per day.
"We will develop a high-quality filter with improved product stability by adding an antibacterial function to the aligned membrane,” Prof. Kim said. “We will also ramp up output by expanding the production facilities after winning approval from the Ministry of Food and Drug Safety." The face mask developed by the research team has a pocket between the interior and surface sides where a filter can be inserted. The filter can be replaced after washing 10 to 20 times and the face mask can also be washed.
On top of that, the team also confirmed that the face mask’s mechanical durability was excellent. It maintained a filtering effect of a KF80 mask (80 percent filtration efficiency) even after being bended 4,000 times.