Modern HVAC systems face increasing demands for particulate filtration, with requirements to capture particles as small as 0.3μm while maintaining acceptable pressure drops across the filter media. Traditional filtration materials struggle to achieve both high capture efficiency and low pressure differential, particularly when targeting ultrafine particles and maintaining MERV ratings above 13.

The fundamental challenge lies in balancing filtration efficiency against pressure drop penalties that impact system energy consumption and operating costs.

This page brings together solutions from recent research—including electrospun nanofiber layers with controlled porosity, metal-doped nano-absorbent structures, biodegradable filter media, and composite designs incorporating sacrificial particles for pore formation. These and other approaches demonstrate how nanofiber technology can achieve superior filtration performance while addressing practical concerns of energy efficiency and maintenance.

1. Nanofiber Air Filter Material with Integrated Non-Woven and Support Layers via Ultrasonic Welding

SHANDONG HUANGHE DELTA INSTITUTE OF TEXTILE SCIENCE AND TECHNOLOGY CO LTD, 山东黄河三角洲纺织科技研究院有限公司, 2023

A nanofiber air filter material with enhanced filtration efficiency and resistance, achieved through a novel preparation method that integrates non-woven fabric, nanofiber filter layer, and support layer. The material combines a non-woven substrate with a nanofiber filter layer and a support layer, then combines them through ultrasonic welding. This approach enables the creation of ultra-efficient air filters with high porosity and controlled pore size, while maintaining the structural integrity of the non-woven substrate. The nanofiber filter layer is prepared using silk technology, which enables precise control over the fiber structure and porosity. The combination of these components results in a filter material with significantly improved filtration efficiency compared to conventional materials.

2. Electrostatic Precipitator Air Filter with Rigid Frame and High-Efficiency Media for HVAC Systems

GRAPHIC ERA DEEMED TO BE UNIVERSITY, 2023

Air filtration device for HVAC systems with improved indoor air quality and reduced energy consumption through the use of a specialized electrostatic precipitator air filter. The filter captures ultrafine particles, allergens, and airborne pollutants that conventional filters may miss. The electrostatic precipitator filter has a rigid frame, filter media restrained, and high-efficiency media to enhance filtration efficiency and reduce maintenance needs compared to traditional filters.

3. Biodegradable HVAC Filter Media with Electrospun Nanofiber Layer Comprising Biodegradable Polymers

NXTNANO LLC, 2023

Biodegradable filter media for HVAC applications that can be fully composted after use. The filter consists of biodegradable base media and a biodegradable nanofiber layer made by electrospinning. The nanofiber layer is formed from biodegradable polymers like PCL, PLA, and PHA. The filter has a filtration efficiency of at least MERV 11. The biodegradable components allow the filter to break down in composting environments, reducing waste compared to conventional HVAC filters with non-biodegradable parts.

US2023108099A1-patent-drawing

4. Air Filter Material with Differential Pressure Calendered Support Layer and Melt-Blown Nanoweb Layer

CLEAN & SCIENCE CO LTD, 2022

Air filter material with enhanced electrostatic properties for maintaining filtration efficiency even at reduced static forces. The material comprises a support layer and nanoweb layer, where the support layer is fabricated through differential pressure calendaring and the nanoweb layer is produced through melt blowing of thermoplastic polymer raw materials. The nanoweb layer provides high surface area and electrostatic charge density, while the support layer enhances filter stability under reduced electrostatic conditions.

KR20220049719A-patent-drawing

5. Non-Woven Air Conditioner Filter Screen with Nanofiber Layer and Antibacterial Coating

佛山迈薄睿科技有限公司, 2022

A non-woven air conditioner filter screen with enhanced filtering performance through nanofiber technology. The screen features a nanofiber layer with a unique antibacterial coating, allowing it to effectively capture airborne contaminants while maintaining high airflow efficiency. The nanofiber layer's high surface area-to-mass ratio enables superior filtration capabilities, particularly against bacteria and viruses, while the antibacterial coating prevents the growth of microorganisms. This design enables improved air quality control in air-conditioning systems.

CN216159175U-patent-drawing

6. Nanofiber Filter with Metal-Doped Nano-Absorbent Structure on Polymer Membrane

Nanofly Filtration Technology Co., Ltd., 2022

Nanofiber filter that combines VOC removal and pathogen elimination capabilities through a unique metal-doped nano-absorbent structure. The filter comprises a base layer of polymer non-woven membrane and a nanofiber layer containing hydrophobic synthetic polymer with metal-doped nano-active absorbing particles. The metal ions in the particles activate against VOCs and pathogens, while maintaining air flow. The filter is manufactured using an electrospinning process, with the metal-doped nano-absorbent particles achieving a weight concentration of 0.2-5% of the organic solvent.

CN111569531B-patent-drawing

7. Nanofiber Air Filter Medium with Stacked Composite Nanofiber Layers and Integrated Nano-Powder Components

CHANG-FONG TEXTILE TECHNOLOGY CO LTD, 2022

A nanofiber air filter medium with enhanced adsorption performance, featuring a composite nanofiber filtration layer that combines multiple nanometer composite nanofiber layers. The medium comprises a support material and a composite nanofiber filtration layer, where the composite nanofiber layers are deposited and stacked on the support material surface. The nanometer composite nanofiber layers comprise first nano-powder composite nanofiber, second nano-powder composite nanofiber, and third nano-powder composite nanofiber. The composite nanofiber filtration layer achieves superior adsorption performance, including formaldehyde adsorption efficiency greater than 95%, 0.3 μm powder dust filtration efficiency greater than 90% at a 5.3 cm/sec flow rate, and pressure loss less than 7 mmH2O.

8. Nanofiber Filter with Pore-Forming Sacrificial Particle-Enhanced Yarn Structure

LG CHEM LTD, 2021

A nanofiber filter that achieves both high dust collection efficiency and low differential pressure characteristics. The filter comprises nanofibers with pores formed through entangled nanofiber yarns, where the pores are created by the sacrificial particles incorporated into the fiber yarn during spinning. These particles selectively etch and form pores in the fiber yarn, allowing the filter to achieve high dust collection efficiency while maintaining low differential pressure. The sacrificial particles are incorporated into the yarn during the spinning process, and the filter is then treated with an etching solution to selectively remove them, creating the desired pore structure.

KR20210048332A-patent-drawing

9. Washable HVAC Filter Media with Nanofiber Layer Between Meltblown Pre-Filter and Nonwoven Layer

NXTNANO LLC, 2021

Washable HVAC filter media comprising a nanofiber layer disposed between a pre-filter layer comprising meltblown fibers and a nonwoven layer. The media achieves initial filtration efficiency of at least MERV 11 as measured according to the ASHRAE 52.2 standard. The media comprises a pre-filter layer with a basis weight of 20 to 40 gsm, a nonwoven layer with a basis weight of 20 to 40 gsm, and a nanofiber layer with a filtration efficiency of at least MERV 9, MERV 10, MERV 11, MERV 12, MERV 13, MERV 14, MERV 15, MERV 16, or MERV 17.

10. Composite Filter Medium with Electrostatically Treated Fibers and Nanofiber Web

AMOGREENTECH CO LTD, 2021

A filter medium and composite filter comprising the same material that maintains high filtration efficiency even after prolonged use. The medium comprises electrostatically treated fibers that adsorb dust particles, with the treatment process maintaining electrostatic force. The medium is combined with a nanofiber web that accumulates on one surface, forming a composite filter. The nanofiber web has a specific pore size and density, while the medium maintains its electrostatic properties. This combination enables long-term performance without compromising filtration efficiency, making it suitable for industrial applications where filter media life is critical.

WO2021015554A1-patent-drawing

11. Nanofiber Filter Material with Controlled Slip Effect Structure and High Surface Area

ZHEJIANG GOLDENSEA ENVIRONMENT TECH CO LTD, 2021

A nanofiber filter material that significantly improves air filtration efficiency while maintaining lower resistance compared to conventional ultra-fine glass fiber filters. The material achieves this through a novel nanofiber structure that combines the high surface area of nanofibers with controlled slip effects during airflow. This unique nanofiber architecture enables effective dust capture while maintaining optimal gas flow characteristics, thereby reducing energy consumption and noise in air filtration systems. The material's performance surpasses that of ultra-fine glass fiber filters in terms of filtration efficiency and resistance, while maintaining a comparable dust holding capacity.

12. Air Filter with Woven Fabric and Nanofiber Filaments on Substrate

E FIOCCHI, 2020

A high-performance air filter comprising woven fabric and nanofiber filaments. The filter structure incorporates the fine fiber material of the present invention, which is formed on the filter substrate and adheres to the filter substrate. This unique nanofiber material provides enhanced filtration capabilities through its unique surface properties.

13. Filter System with Nanofiber Porous Matrix and Nanostructured Functional Layer

刘向文, 北京米思卫仕智能科技有限公司, XIANGWEN LIU, 2020

Air filter, mask, and air purifier that utilize advanced filter technologies beyond conventional melt-blown materials. The filter comprises a filter layer comprising a porous matrix of nanofibers with diameters ranging from 10 to 1000 nm, combined with a functional layer comprising a nanostructured material that enhances both filtration and adsorption properties. This dual-layer architecture enables the filter to maintain optimal performance across a wide range of operating conditions, including high temperatures and humidity, while maintaining its functional integrity.

CN211302355U-patent-drawing

14. Air Conditioner with Integrated Nano-Filter Assembly and Humidity Management System

DOWOO ENG & ENERGY CO LTD, 2020

Air conditioner with integrated dust removal and humidity management. The system features a nano-filter assembly in the control zone, where air is filtered as it enters the room. The assembly includes multiple nanofibers that capture microscopic dust particles, while also incorporating a humidity management system to maintain optimal indoor conditions. The system integrates with conventional air conditioning components, with the nano-filter assembly positioned between the filter and supply blower. The assembly includes a cleaning mechanism that utilizes water to maintain the nanofibers, ensuring continuous dust capture.

15. Nanofiber Sheet Assemblies with Controlled Bundle Spacing and Diameter via Solvent-Induced Shrinkage

LINTEC OF AMERICA INC, 2019

Nanofiber sheet assemblies that combine mechanical durability with gas permeability. The assemblies feature nanofibers with precisely controlled bundle spacing and diameter, achieved through controlled shrinkage of the non-fixed nanofiber sheet during exposure to water and organic solvent droplets. This controlled shrinkage enables the formation of uniform nanofiber bundles with consistent gap sizes, enabling gas filtration while maintaining mechanical integrity. The assemblies exhibit superior gas permeability compared to conventional nanofiber sheets, with high gas transmission rates and minimal particle retention.

TW201941916A-patent-drawing

16. Nanofiber Filter with Electrospun Membrane and Multi-Layer Structure for Automotive Air Conditioning Systems

ZHEJIANG LONG BEACH NEW MATERIALS CO LTD, Zhejiang Longbi New Materials Co., Ltd., 2019

A nanofiber filter for automotive air conditioning systems that combines high filtration efficiency with improved stability and resistance. The filter comprises a nanofiber membrane comprising a substrate support layer, nanofiber layer, and non-woven protective layer, where the nanofiber layer has an average diameter between 50-300 nm and thickness less than 50 um. The nanofiber membrane is prepared through electrospinning using a solvent system that enables controlled fiber diameter and thickness. The nanofiber membrane is then integrated into a support structure, creating a stable and durable filter element.

CN209530316U-patent-drawing

17. Air Filter with Cellulose Nanofiber-Based Adsorbent and Partitioned Airflow System

SHINWA TECH CO LTD, 2019

Air filter with a cellulose nanofiber-based adsorbent that can be regenerated at lower temperatures compared to traditional silica gel-based filters. The filter comprises cellulose nanofibers with modified hydroxyl groups that enable desorption of water molecules at temperatures below 100°C. The cellulose nanofibers are produced through freeze-drying of cellulose nanofiber dispersion, resulting in a material with high surface area and adsorption capacity. The filter structure features a partitioned airflow system with cellulose nanofiber-filled channels, allowing efficient gas exchange while maintaining structural integrity.

JP2019181391A-patent-drawing

18. Nanomaterial Comprising Beaded Nanofibers with Randomly Interwoven Network Structure

FOCUS INDUSTRIES LTD, 2019

A nanomaterial for high-efficiency air filtration that improves the mechanical strength of nanofiber filters to prevent pore collapse. The nanomaterial is made by randomly dispersing beads with a diameter of 2-20 microns along the nanofibers as they are being spun. These beaded nanofibers are then deposited to create a randomly interwoven network with 3D pores. The beads support the nanofibers and prevent the pores from collapsing during use.

WO2019184099A1-patent-drawing

19. Filter Material Comprising Nanoscale Porous Carbon Nanotubes, Zeolites, and Graphene Oxide Layer

GUANGDONG WEITIAN NEW ENVIRONMENTAL PROTECTION MATERIAL CO LTD, 2019

A filter material for high-efficiency, energy-saving, environmentally friendly, and healthy air conditioners that achieves these goals through a novel combination of materials and design. The filter material comprises a matrix of nanoscale, porous carbon nanotubes and zeolites, combined with a thin layer of graphene oxide, all integrated into a single, ultra-efficient filter element. This hybrid structure enables unparalleled air filtration performance while minimizing energy consumption and environmental impact.

20. Electret Nanofiber Filter Material with Controlled Electrospinning-Induced Charge Stabilization

JIAXING FURUIBANG NEW MATERIAL TECH CO LTD, 2019

Electret nanofiber filter material for HVAC systems that combines enhanced filtration performance with improved stability and cost-effectiveness. The material is prepared through a novel electrospinning process that rapidly cools and solidifies polymer-dissolved liquid mixtures at the fiber exit, creating a permanent electret structure. The process incorporates a constant-rate release system that precisely controls the cooling and solidification process, ensuring uniform charge distribution and fiber alignment. This approach eliminates the conventional issues of charge dissipation and fiber degradation associated with traditional electret preparation methods. The resulting electret nanofiber filter material exhibits superior filtration efficiency while maintaining low pressure resistance compared to conventional melt blown filter materials.

21. Air Conditioning System Filter with Electrospun Nanofilm-Coated Gauze Assembly and Structural Support Strips

22. Automotive Air Conditioning Filter with Nano-Fiber Membrane and Composite Layer Structure

23. Air Conditioning Filter Element with Non-Woven Base and Melt-Blown Nanofiber Layer

24. Air Conditioning Filter System with Nano-Space Cartridge and Modular Filter Assembly

25. Self-Supporting Filter Material with Hyperbolic Density Distribution in Fiber Matrix

Get Full Report

Access our comprehensive collection of 35 documents related to this technology