IP Library › Granted Patent US 12,734,378
Granted Patent B2
US 12,734,378 · App. 18/030,443 · Granted Sep 15, 2026

Personal protective anti-viral face mask

Inventors: James E. Fay, III (Boulder, CO); Richard Dennis Vigil (Ames, IA); John A. Soderquist (Dorado, PR); Andrew S. Heller (Ames, IA); Trung Lo Deo (Urbandale, IA); Cameron Lynch (Iowa City, IA); Danilo R. Manfre (West Des Moines, IA); Beate Schmittmann (Ames, IA)
Assignee: lowa State University Research Foundation, Inc.
A62B23/02A41D13/11A62B7/10A62B18/025B01D39/08B01D46/0028B01D46/0036B01D46/0041B01D46/2411B01D2239/0407B01D2239/0442B01D2239/0478B01D2239/0618B01D2279/65
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Quick Facts
Patent No.
US 12,734,378
App. No.
18/030,443
Granted
Sep 15, 2026
Kind
B2
Abstract

An entrainment-based filtering system for use in connection with a facemask or respirator that includes: a filter housing defining an interior volume comprising at least one airflow pathway having an airflow pathway length that is longer than the length of the interior volume and spaced within the interior volume; and a plurality of entrainment substrates. The plurality of entrainment substrates is positioned within the at least one airflow pathway and the plurality of substrates and the dimensions of the at least one airflow pathway together function to entrain particles on the surface of the chemically coated entrainment substrates and prevent at least 95% of particles traveling through the at least one airflow pathway from exiting the entrainment-based filter.

Claims (26)

1 . An entrainment-based air filter comprising:

a housing defining an interior volume comprising at least one airflow pathway having an airflow pathway length spaced within the interior volume; and

a plurality of entrainment beads that are substantially free or free of pores capable of filtering by entrapping particulates wherein the plurality of entrainment beads is within the at least one airflow pathway; and

wherein the plurality of entrainment beads and the dimensions of the at least one airflow pathway work together to establish a residence time within the housing sufficient to entrain particulates on a surface of the plurality of entrainment beads by adsorption or absorption of the particulates and thereby prevent at least 95% of particulates traveling through the at least one airflow pathway from exiting the entrainment-based air filter.

2 . The entrainment-based air filter of claim 1 , wherein the plurality of entrainment beads all comprises the same type of inert material and the entrainment-based air filter is a threaded cartridge configured to be engaged with a threaded attachment location of a facemask.

3 . The entrainment-based air filter of claim 1 , wherein the plurality of entrainment beads is free of pores greater than 50 nm in size and are free of any coating thereon and the particulates comprise a virus having a size of about 0.3 microns or smaller.

4 . The entrainment-based air filter of claim 3 , wherein the plurality of entrainment beads is free of pores greater than 2 nm in size and are free of any coating thereon.

5 . The entrainment-based air filter of claim 1 , wherein the entrainment-based air filter is free of any activated carbon, activated alumina, silica gel or zeolites and the entrainment-based air filter does not utilize entrapment-based or irradiation-based systems to capture or eliminate virus traveling within the at least one airflow pathway during use.

6 . The entrainment-based air filter of claim 1 , wherein the at least one airflow pathway is a plurality of airflow pathways and the plurality of entrainment beads is chosen from the group consisting of boron-modified polystyrene beads and polyhydroxylated particles.

7 . The entrainment-based air filter of claim 1 , wherein the at least one airflow pathway comprises at least two spiral-shaped airflow pathways that are within the interior volume of the housing and concentric with one another about a central axis that runs the length of the housing and wherein the plurality of entrainment beads are coated with a non-volatile liquid or a bifunctional chemical chosen from the group consisting of gluconic acid and ascorbic acid in solid or liquid form.

8 . The entrainment-based air filter of claim 7 , wherein the housing is a cylindrically shaped housing and the entrainment-based air filter further comprises a composite panel affixed to a top of the at least one airflow pathway and the plurality of entrainment beads form at least one packed bed layer of entrainment beads.

9 . The entrainment-based air filter of claim 7 further comprising a composite panel affixed to an opposite end of the at least one airflow pathway and wherein the composite panel affixed to the top of the at least one airflow pathway and the composite panel affixed to the opposite end of the at least one airflow pathway each comprise a non-woven sandwiched between two layers of fabric material chosen from the group consisting of a spunbond material, a hydroentangled spunlace material, a melt blown material, a spunbond/melt blown/spunbond laminate material, and an air-laid material.

10 . The entrainment-based air filter of claim 7 , wherein the plurality of entrainment beads is positioned within each of the at least two spiral-shaped airflow pathways.

11 . The entrainment-based air filter of claim 10 , wherein the entrainment-based air filter eliminates at least 99% of virus that are smaller than 0.3 microns in size that pass through the entrainment-based air filter during use by a human.

12 . The entrainment-based air filter of claim 1 , wherein the plurality of entrainment beads is coated with a material chosen from the group consisting of a surfactant, a non-volatile liquid and a bifunctional chemical component.

13 . The entrainment-based air filter of claim 1 , wherein the plurality of entrainment beads is coated with a bifunctional chemical component that bonds to the plurality of entrainment beads and a virus and wherein the plurality of entrainment beads are inert and the plurality of entrainment beads do not have pores.

14 . The entrainment-based air filter of claim 1 , wherein the plurality of entrainment beads is coated with a hydroxylated carboxylic acid.

15 . An entrainment-based filter comprising a housing defining an interior volume having at least one airflow pathway having an airflow pathway length that is longer than the length of the interior volume and spaced within the interior volume; and a plurality of entrainment substrates that are at least partially coated with a coating composition and positioned within the at least one airflow pathway; wherein the plurality of entrainment substrates and the dimensions of the at least one airflow pathway work together to slow a flowrate of particulates traveling within the at least one airflow pathway proximate the plurality of entrainment substrates to a flowrate where the particulates are adsorbed or absorbed on a surface of the plurality of entrainment substrates; and wherein the coating composition comprises a coating chosen from the group consisting of: a non-volatile, thixotropic liquid; a polyhydroxylated carboxylic acid; sialic acid; ascorbic acid; gluconic acid; a cellulose, polyethylene glycol; an amphiphilic organoboron block copolymer poly(styreneboronic acid)-block-polystyrene, and mixtures thereof.

16 . The entrainment-based filter of claim 15 , wherein the entrainment-based filter eliminates at least 99% of virus that are smaller than 0.3 microns in size that pass through the entrainment-based filter during use by a human.

17 . The entrainment-based filter of claim 16 , wherein the at least one airflow pathway comprises at least two spiral-shaped airflow pathways that are within the interior volume of the housing and concentric with one another about a central axis that runs the length of the housing.

18 . An entrainment-based filter comprising:

a housing defining an interior volume comprising at least one airflow pathway spaced within the interior volume; and

a plurality of entrainment substrates that are substantially free or free of pores capable of filtering by entrapping particulates and positioned within the at least one airflow pathway; and

wherein the plurality of entrainment substrates and the dimensions of the at least one airflow pathway work together to entrain particulates on a surface of the plurality of entrainment substrates by adsorption or absorption of the particulates and prevent at least 95% of particulates traveling through the at least one airflow pathway from exiting the entrainment-based filter.

19 . The entrainment-based filter of claim 18 , wherein the particulates comprise at least one type of airborne biological material chosen from the group consisting of a mold, Bacillus anthracis, Mycobacterium tuberculosis , the virus that causes SARS, Pandemic Novel Swine Origin Influenza A (H1N1), Ebola virus, and the COVID-19 virus; and wherein the at least one airflow pathway comprises at least one spiral-shaped airflow pathway spaced within the interior volume of the housing and wherein the plurality of entrainment substrates are boron-modified polystyrene beads.

20 . The entrainment-based filter of claim 18 , wherein the at least one airflow pathway comprises at least two spiral-shaped airflow pathways that are within the interior volume of the housing and concentric with one another about a central axis that runs the length of the housing and wherein the entrainment-based filter further comprises a first mesh plate and a second mesh plate on each side of the housing wherein the first mesh plate and the second mesh plate on each side of the housing support a nonwoven spunbond panel that fits over the first mesh plate or the second mesh plate and prevents the nonwoven spunbond panel from collapsing in the interior of the housing during inhalation.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 2, 2026
From: FAY, JAMES E., III; VIGIL, RICHARD DENNIS, DR.; SODERQUIST, JOHN A., DR.; HELLER, ANDREW S.; DEO, TRUNG LO; LYNCH, CAMERON; MANFRE, DANILO R.; SCHMITTMANN, BEATE, DR.
To: IOWA STATE UNIVERSITY RESEARCH FOUNDATION, INC.
Reel/Frame 073351/0570 →
Continuity (3)
Continuation 17103501 · Nov 24, 2020
Provisional Application 63087658 · Oct 5, 2020
Related Publication 20230372747A1 · Nov 23, 2023
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