Nanofiber filter media for clean air in the vehicle cabin
For cabin air filtration in vehicles MANN+HUMMEL is now using Nanofiber technology that can be applied to different media and materials.
Ludwigsburg/ Marklkofen, April 2021 – On its Website the WHO (World Health Organization) accounts for seven million the number of yearly deaths due to air pollution. A big issue is particle pollution.
Over the last years international studies have shown the impact of fine dust on our health: the smaller the particles are, the more dangerous they are. PM2.5 particles that are smaller than 2.5 µm can go deeper into human respiratory system and can cause severe health issues, even death.
For the separation of finest particles MANN+HUMMEL has been successfully using nanofiber technology for a number of years in series applications for the commercial vehicles sector. Now this technology is also used in cabin air filters for Automotive applications reducing the number of pollutants that vehicle occupants breathe, and thus improving the air quality in the vehicle cabin.
A high filtration efficiency
The nanofiber filter media produced by MANN+HUMMEL consists of a carrier media and an extremely thin layer of ultra-fine polymer fibers. The fibers with a diameter of less than one micrometer are approximately 200 times smaller than the fibers of the carrier material or 650 times smaller than a human hair. These ultrafine fibers and their large number ensure a higher separation efficiency of fine particles like PM2.5 and PM1, and also ultrafine particles (see note 1), keeping at the same time a low air flow resistance thanks to the low grammage of the fiber layer.
A ePM1 classification of the nanofiber filter media was achieved according to ISO 16 890, which means that the filtration efficiency of PM1 particles can reach up to 95 % (see note 2).
MANN+HUMMEL has a granted patent in Germany that protects specific aspects of the filter media and the underlying production process.
A stable long term efficiency over life time
The stable long term efficiency over the whole filter life time needs to be highlighted. Compared with traditional electret filter media, the nanofiber media shows a much lower reduction of filtration efficiency after ageing. This effect is visible in laboratory, but also in field tests.
Furthermore the nanofiber media is highly resistant against extreme environmental conditions, as humidity and temperature fluctuations.
Possible combination with other filter media
And last but not least, another attractive aspect of this technology is its possible combination with any further media like particle filter media, filter media with activated carbon (for the adsorption of gases and odors) or/and bio functional layer (for the additional inactivation of microorganisms). This enables varieties of customized solutions to meet the requirements of vehicle manufacturers.
PM2.5: Fine inhalable particles with a diameter less than 2.5 µm which can reach the lungs.
PM1: Very fine particles with a diameter less than 1 µm.
UFP: According to the most common definitions, ultrafine particles (UFP) or ultrafine dust are airborne particles with a diameter between 1 and 100 nanometers (nm) (DIN 2006; ISO 2007; VDI 2009; EPA 2004).
PM1 and UFP are most dangerous since they can pass through the lungs into the bloodstream, transporting toxic compounds to sensitive regions of the body.