Infectious Agent Air Treatment System, Apparatus, and Method

Abstract

An infectious agent attenuating or inactivating personal protective equipment device, such as a surgical mask, multilayer mask or respirator having at least one porous filtering layer impregnated with an infectious agent attenuating or inactivating solution that tries to leave behind an infectious agent attenuating or inactivating attenuator composed of an organic acid that preferably is a citric acid, a humectant that preferably is a gelling humectant that preferably is sorbitol which produces or forms a self activating or self replenishing infectious agent attenuator gel and infectious agent attenuating and inactivating air treatment media having a pH of no greater than 5, preferably no greater than 4 and more preferably no greater than 3.5 which is kept moist and activated at or below the desired pH by moisture in the breath of a person wearing the mask. The solution can include a surfactant, such as preferably a rhamnolipid biosurfactant that reduces surface tension both during impregnation of the solution thereby more uniformly impregnating the solution into the at least one porous filtering layer producing an air treatment media having infectious agent attenuating gel more uniformly distributed throughout. The surfactant remains in the gel and reduces surface tension of aerosols and droplets containing viruses and bacteria entrained in the air flowing through the air treatment media contacting the infectious agent attenuating gel more rapidly and efficiently attenuating or inactivating the viruses and bacteria preferably also destroying them by lysing them.

Claims

1. An air treatment system comprised of an infectious agent attenuating or inactivating air treatment media having at least a plurality of pairs of air flow passages formed therein in which is disposed an infectious agent attenuator configured to attenuate or inactivate infectious agents in the air flowing therethrough, the infectious agent attenuator comprised of (a) a moisture-activated infectious agent attenuating or inactivating biocide and (b) a humectant that captures moisture from the air flowing through the at least the plurality of pairs of the air flow passages formed in the infectious agent attenuating or inactivating air treatment media in which the infectious agent attenuator is disposed thereby maintaining infectious agent attenuator attenuating or inactivating effectiveness by maintaining activation of the infectious agent attenuating or inactivating biocide.

2. The air treatment system of claim 1, wherein the moisture-activated infectious agent attenuating or inactivating biocide is comprised of citric acid and the moisture-capturing humectant is comprised of sorbitol.

3. The air treatment system of claim 2, wherein the infectious agent attenuator is further comprised of a surfactant that facilitates attraction of infectious agents in the air flowing through the at least the plurality of pairs of the passages formed in the infectious agent attenuating or inactivating air treatment media thereby increasing the effectiveness of attenuation or inactivation of infectious agents in the flowing air.

4. The air treatment system of claim 3, wherein the surfactant is comprised of a rhamnolipid surfactant.

5. The air treatment system of claim 2, wherein the infectious agent attenuator is further comprised of a surfactant that attracts and encapsulates in the infectious agent attenuator infectious agents in the air flowing through the at least the plurality of pairs of the passages formed in the infectious agent attenuating or inactivating air treatment media thereby increasing effectiveness of attenuation or inactivation of infectious agents in the flowing air.

6. The air treatment system of claim 5, wherein the surfactant is comprised of a rhamnolipid surfactant.

7. The air treatment system of claim 1, wherein the infectious agent attenuator is further comprised of a surfactant.

8. The air treatment system of claim 1, wherein the moisture-activated infectious agent attenuating or inactivating biocide is composed of a solution of about 88% water by solution weight and about 12% by solution weight of a mixture of at least 80% citric acid by mixture weight and no more than 20% sorbitol by mixture weight.

9. The air treatment system of claim 1, wherein the moisture-activated infectious agent attenuating or inactivating biocide is composed of a solution of about 88% water by solution weight and about 12% by solution weight of a mixture of at least 80% citric acid by mixture weight and no more than 20% sorbitol by mixture weight.

10. The air treatment system of claim 1, wherein the moisture-activated infectious agent attenuating or inactivating biocide is composed of a solution of about 88% water by solution weight and about 12% by solution weight of a mixture of at least 80% citric acid by mixture weight and no more than 20% sorbitol by mixture weight.

11. An air treatment system comprised of an infectious agent attenuating or inactivating air treatment media having at least a plurality of pairs of air flow passages formed in and extending therethrough along which is disposed an infectious agent attenuating or inactivating attenuator configured to attenuate or inactivate infectious agents in air flowing through the at least the plurality of pairs of the air flow passages formed in and extending through the infectious agent attenuating or inactivating air treatment media, the infectious agent attenuating or inactivating attenuator comprised of (a) an infectious agent attenuating or inactivating biocide and (b) a humectant that captures moisture from the air flowing through the at least the plurality of pairs of air flow passages formed in and extending through the infectious agent attenuating or inactivating air treatment media maintaining infectious agent attenuation and inactivation effectiveness by the captured moisture retaining a pH thereof no greater than a predetermined pH or within a predetermined pH range that maintains infectious agent attenuation or inactivation effectiveness of the infectious agent attenuating or inactivating attenuator.

12. The air treatment system of claim 11, wherein the moisture-activated infectious agent attenuating or inactivating biocide is comprised of citric acid and the moisture-capturing humectant is comprised of sorbitol.

13. The air treatment system of claim 12, wherein the infectious agent attenuator is further comprised of a surfactant that facilitates attraction of infectious agents in the air flowing through the at least the plurality of pairs of the passages formed in the infectious agent attenuating or inactivating air treatment media thereby increasing the effectiveness of attenuation or inactivation of infectious agents in the flowing air.

14. The air treatment system of claim 13, wherein the surfactant is comprised of a rhamnolipid surfactant.

15. The air treatment system of claim 12, wherein the infectious agent attenuator is further comprised of a surfactant that attracts and encapsulates in the infectious agent attenuator infectious agents in the air flowing through the at least the plurality of pairs of the passages formed in the infectious agent attenuating or inactivating air treatment media thereby increasing effectiveness of attenuation or inactivation of infectious agents in the flowing air.

16. The air treatment system of claim 15, wherein the surfactant is comprised of a rhamnolipid surfactant.

17. The air treatment system of claim 11, wherein the infectious agent attenuator is further comprised of a surfactant.

18. The air treatment system of claim 11, wherein the moisture-activated infectious agent attenuating or inactivating biocide is composed of a solution of about 88% water by solution weight and about 12% by solution weight of a mixture of at least 80% citric acid by mixture weight and no more than 20% sorbitol by mixture weight.

19. The air treatment system of claim 11, wherein the moisture-activated infectious agent attenuating or inactivating biocide is composed of a solution of about 88% water by solution weight and about 12% by solution weight of a mixture of at least 80% citric acid by mixture weight and no more than 20% sorbitol by mixture weight.

20. An air treatment system comprised of an infectious agent attenuating or inactivating air treatment media having at least a plurality of pairs of air flow passages extending therethrough, the infectious agent attenuating or inactivating air treatment media comprised of a layer of a perforate or porous filtering material having a plurality of pairs of the air flow passages formed therein, and an infectious agent attenuating or inactivating attenuator disposed in and along the plurality of pair of air flow passages thereby exposing air flowing through the plurality of pairs of the air flow passages to the infectious agent attenuating or inactivating attenuator by contact therewith, the infectious agent attenuating or inactivating attenuator comprised of a biocide and a humectant that captures moisture in the air flowing through the plurality of pairs of the air flow passages that maintains the infectious agent attenuating or inactivating attenuator below a desired predetermined pH or within a desired predetermined pH range that maintains infectious agent attenuation or inactivation effectiveness thereof.

Description

DRAWING DESCRIPTION

[0021] One or more preferred exemplary embodiments of the invention are illustrated in the accompanying drawings in which like reference numerals represent like parts throughout and in which:

[0022] FIG. 1 is a top plan view of an elongate oblong infectious agent attenuating or inactivating air treating filter panel of an infectious agent attenuating or inactivating air treatment media formed of a layer of perforate or porous air filtering material treated with an infectious agent attenuating or inactivating attenuator;

[0023] FIGS. 2A and 2B depict a first pair of side by side enlarged photomicrographs of a fragmentary top plan view of an enlarged portion of the oblong layer of perforate or porous air filter material before and after treatment with infectious agent attenuator;

[0024] FIGS. 3A and 3B depict a second pair of side by side enlarged photomicrographs of a fragmentary side elevation view of an enlarged portion of a side edge of the oblong layer of perforate or porous air filter material before and after treatment with infectious agent attenuator;

[0025] FIG. 4 is a fragmentary perspective cutaway view of a 3-ply or 3-layer infectious agent attenuating or inactivating surgical mask having a first ply or outermost layer composed of a polypropylene spunbound non-woven fabric, a second or middle ply or layer composed of a layer of infectious agent attenuating or inactivating air treatment media made of a perforate or porous air filtering material composed of a meltblown nonwoven fabric impregnated with infectious agent attenuator, and a third ply or innermost layer that is a support layer that composed of a mesh made of a polypropylene spunbound non-woven fabric;

[0026] FIG. 5 is a perspective exploded view of the 5-plys or 5-layers of a 5-ply or 5-layer infectious agent attenuating or inactivating air filtering personal protective mask of the present invention that preferably is an N95 respirator mask having a nonwoven first or outer layer made of a fabric like a polypropylene spunbound non-woven fabric, a second outer intermediate double meltblown layer composed of infectious agent attenuating or inactivating air treatment media, a third or middle double nonwoven layer composed of a polypropylene spunbound non-woven fabric, a fourth or inner intermediate double meltblown layer composed of infectious agent attenuating or inactivating air treatment media, and a fifth or inner double nonwoven layer composed of a polypropylene spunbound non-woven fabric;

[0027] FIG. 6 is a lower front left perspective view of a person removably wearing a infectious agent attenuating or inactivating respirator assembly of the present invention equipped with a middle layer of air filtering and infectious agent attenuating or inactivating construction composed of infectious agent attenuating or inactivating air treatment media sandwiched between an outer perforate hardshell respirator cover and an inner respirator frame to which ear loops or head anchor straps extend outwardly from; and

[0028] FIG. 7 is a front top right perspective exploded view of the infectious agent attenuating or inactivating respirator assembly of FIG. 6.

[0029] Before explaining one or more embodiments of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description and illustrated in the drawings. The invention is capable of other embodiments or being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.

DETAILED DESCRIPTION

[0030] FIG. 1 illustrates a preferred embodiment of an infectious agent attenuating or inactivating air treatment media 420 configured for use in a personal protective air filtering device 422a-422c, such as in the form of a surgical mask 460, like the 3 ply or 3 layer infectious agent attenuating or inactivating surgical mask 460 depicted in FIG. 4, an N-95 or KN-95 air filtering respirator or mask 462, like 5 ply or 5 layer the infectious agent attenuating or inactivating N95 air filtering respirator or mask 462 depicted in FIG. 5, or a hardshell solid frame respirator 464, like the infectious agent attenuating or inactivating respirator 464 equipped with adjustable head and neck straps 482, a perforate concave hardshell outer cover 484 and an cushioned substantially rigid inner frame 486 to which the straps 482 anchor and which has an exhalation valve 488 as depicted in FIGS. 6 and 7, which each employs at least one layer 485 of treatment media 420 made of a perforate or porous air filtering material layer 423 treated, preferably impregnated, with an infectious agent attenuator 424 composed of an infectious agent attenuating or inactivating biocide and a humectant included to retain moisture to keep the biocide activated during use and operation of the personal protective air filtering device 422a-422c. In a preferred embodiment, a sufficient amount of the humectant is added to the infectious agent attenuating or inactivating biocide to produce an infectious agent attenuator 424 of the present invention that is a self-activating infectious agent attenuating or inactivating composition because only moisture in air passing through the air treatment media 420 during inhalation and exhalation by a person wearing the personal protective air filtering device 422 is needed to replenish the infectious agent attenuator 424 of the air treatment media 420 with enough moisture to keep it at a desired pH within an optimal pH range at which the air treatment media 420 attenuates and/or inactivates infectious agents in the air passing through.

[0031] FIGS. 2A and 2B depict a first pair of side by side enlarged photomicrographs of a a top surface 475, 475′ of an enlarged portion of the layer of perforate or porous air filter material 423 of FIG. 1 before (FIG. 2A) and after (FIG. 2B) treatment with an infectious agent attenuator 424 that is preferably impregnated therein. FIG. 2A also illustrates that the layer of perforate or porous air filter material 423 has at least a plurality of pairs, i.e. at least 3, of air flow paths or channels 470, 472, 474 which are preferably non-straight or meandering flow paths or channels 470, 472, 474 formed between filaments or fibers 476 of a flexible resilient material 478, such as a material 478 made of a flexible and resilient polypropylene spunbound, meltblown or spunface fabric. It is contemplated that the layer of perforate or porous air filter material can also be made of polyester, cotton, silk or nylon and which can be of woven, nonwoven, knit, meltblown, spunbound or spunface flexible fabric. FIGS. 3A and 3B depict a second pair of side by side enlarged photomicrographs of an enlarged portion of a side edge 480, 480′ of the oblong layer of perforate or porous air filter material 423 of FIG. 1 before and after treatment, preferably impregnation, with infectious agent attenuator 424.

[0032] FIG. 4 illustrates a 3-ply or 3-layer infectious agent attenuating or inactivating surgical mask 460 having a flexible first ply or outermost layer 490 composed of a polypropylene spunbound non-woven fabric, a flexible second or middle ply or layer 492 composed of a layer of infectious agent attenuating or inactivating air treatment media made of a perforate or porous air filtering material 423 composed of a meltblown nonwoven fabric impregnated with infectious agent attenuator 424, and a flexible third ply or innermost layer 494 that is a support layer composed of a mesh made of a polypropylene spunbound non-woven fabric. The mask also has a pair of elastic ear loops 496 and a bendable metal nose clip 498.

[0033] FIG. 5 illustrates a 5-plys or 5-layers of a 5-ply or 5-layer infectious agent attenuating or inactivating air filtering personal protective mask 422b of the present invention that preferably is an N95 respirator mask 462 having a flexible nonwoven concave first or outer layer 500 made of a fabric like a polypropylene spunbound non-woven fabric, a flexible second outer intermediate double meltblown layer 502 composed of infectious agent attenuating or inactivating air treatment media 420, a flexible third or middle double nonwoven layer 504 composed of a polypropylene spunbound non-woven fabric, a flexible fourth or inner intermediate double meltblown layer 506 composed of infectious agent attenuating or inactivating air treatment media 420, and a flexible fifth or inner double nonwoven layer 508 composed of a polypropylene spunbound non-woven fabric. In other words, the 5 ply or 5 layer mask 422b is equipped with a pair of inline but spaced apart infectious agent attenuating or inactivating air treatment media layers 502 and 506 providing double the filtering and infectious agent inactivating or attenuating flow volume. Although equipped with elastic ear loops that are not shown in FIG. 4, the outer layer 500 does have an elongate rectangular bendable metal nose clip 510.

[0034] FIGS. 6 and 7 illustrate an infectious agent attenuating or inactivating respirator assembly 464 adapted to be worn over the nose and mouth of a person 512 (FIG. 6). The respirator assembly 464 has a concave middle particulate air filtering layer 485 composed of air filtering and infectious agent attenuating or inactivating media 420 sandwiched between a rigid perforate hardshell outer respirator cover 482 and an inner respirator frame 486 to which adjustable head mounting straps 462 releasably secured around the head 514 and neck 516 of the person 512 wearing the respirator 464 are adjustably anchored.

[0035] As can be seen by looking at the comparison views, treating the layer of perforate or porous air filter material 423 with infectious agent attenuator 424 preferably by impregnating the filter material 423 with infectious agent attenuator 424 coats or lines the fibers and/or filaments 476 producing an infectious agent attenuating or inactivating air treatment media 420 configured so infectious agent carrying air flowing through the reduced diameter or width flow paths or channels 470, 472 and 474 comes into contact with the infectious agent attenuator 424 coating or lining the fibers and/or filaments 476. As a result, airborne liquid aerosols and droplets entrained in the flowing air carry infectious agents, such as one or more viruses, e.g., coronaviruses, such as Sars-Cov-2 viruses, which also contact infectious agent attenuator 424 coating or lining the fibers and/or filaments 476 of the air treatment media 420 attenuating or inactivating the infectious agents in the liquid aerosols or droplets.

[0036] The infectious agent attenuator 424 preferably is a flowable viscous liquid at room temperature, i.e., 20-22° C. or 68-72° F., during application onto the perforate or porous air filtering material layer 423 such that the attenuator 424 becomes impregnated into the filtering material layer 423 by the liquid or liquified attenuator 424 being distributed substantially completely and preferably substantially uniformly throughout the filtering material layer 423. Upon drying of the attenuator 424 impregnated into the filtering material layer 423, preferably by heated and/or convective oven drying in a heated and/or convective drying oven, the attenuator 424 impregnated into the air filtering material layer 423 solidifies producing an infectious agent attenuating or inactivating air treatment media 420 of the present invention having solidified infectious agent attenuating or inactivating attenuator 424 exposed to air flowing therethrough during personal protective air filtering device operation that is substantially uniformly distributed throughout.

[0037] In a preferred embodiment, the flowable liquid infectious agent attenuator 424 is applied to, e.g., impregnated into, the air filtering material layer 423 and is formulated, such as preferably by including a gellant, to increase in viscosity and gel over time during drying producing an infectious agent attenuating or inactivating air treatment media 420 with a moist resilient and pliable infectious agent attenuator gel 427, e.g., preferably indurate gel 427, which will be exposed to air flowing therethrough during personal protective air filtering device operation that congeals substantially uniformly throughout and within the air treatment media 420. The infectious agent attenuator 423 preferably is in the form of a flowable viscous infectious agent attenuator gel 427 that is flowable at room temperature during application to, e.g., impregnating into, the air filtering material layer 423 as a flowable liquid that increases in viscosity and gels as it solidifies after application to the air treatment media 420 as it dries.

[0038] A preferred infectious agent attenuator formulation is composed of a biocide and a gellant configured not only to retain water, i.e., a gellant that also is a humectant, to keep the biocide activated, preferably self-activated by human breath moisture during personal protective air filtering device operation, but also to form an infectious agent attenuator gel, preferably during or after application to the air filtering material layer 423 producing an infectious agent attenuating air treatment media 420 of the invention that is ready for use in a personal protective air filtering device 425 like a surgical mask, respirator, or another type of personal protective equipment (PPE). If desired, such a formulation of an infectious agent attenuator 424 can have other constituents including, for example, one or more wetting agents, one or more viscosity modifiers and/or stabilizers, one or more pH modifiers and/or stabilizers, one or more surfactants, e.g., a glycolipid biosurfactant that is a rhamnolipid biosurfactant or supersurfactant, as well as one or more other constituents.

[0039] An infectious agent attenuator 424 of the present invention is produced using an infectious agent attenuator solution composed of (a) an infectious agent attenuator precursor mixture composed of between 55-85% of an acid, preferably a tribasic acid or triprotic acid that more preferably is an organic acid, preferably citric acid, and between 15-45% of a humectant that preferably is a gelling humectant, which more preferably is an organic gelling humectant, preferably sorbitol, and (b) the remainder water. The infectious agent attenuator solution used to treat the air filtering material layer 423 to produce the infectious agent attenuating air treatment media 420 with the infectious agent attenuator 424 coated thereon and/or impregnated therein after drying is composed of between 5-20% of the precursor mixture and the remainder, between 80-95%, composed of water into which the concentrated precursor mixture is added and mixed.

[0040] A preferred infectious agent attenuator 424 of the present invention is produced using an infectious agent attenuator solution composed of (a) an infectious agent attenuator precursor mixture composed of between 60-80% of a naturally occurring organic acid, preferably citric acid, and between 20-40% of a naturally occurring organic humectant that preferably is a naturally occurring organic gelling humectant, preferably sorbitol, and (b) the remainder composed of water. The infectious agent attenuator solution used to treat the filtering material layer 423 to produce the infectious agent attenuating air treatment media 420 coated and/or impregnated with the infectious agent attenuator 424 is composed of between 10-15% of the precursor mixture and the remainder, between 85-90%, composed of water with which the precursor mixture is added and mixed.

[0041] A particularly preferred infectious agent attenuator 424 is produced using an infectious agent attenuator solution having a formulation composed of (a) a precursor mixture of at least 80% of an acid, preferably a naturally occurring organic acid, more preferably citric acid, and no more than 20% of a humectant that preferably is a gelling humectant, more preferably a naturally occurring organic gelling humectant, preferably sorbitol, and (b) water. The infectious agent attenuator solution produced is a flowable liquid solution capable of being applied using a dip-coating application method or being sprayed on using a sprayer or the like that is composed of about 12%±1.5% of the precursor mixture and the remainder, about 88%±1.5%, water mixed together and applied to the air filtering material layer 423 to coat the layer 423 and preferably substantially uniformly impregnate the layer 423 with the solution that solidifies during drying into infectious agent attenuator 424 preferably in the form of an infectious agent attenuator gel 427 transforming the infectious agent attenuator gel-coated and impregnated air filtering material layer 423 into air-filtering infectious agent attenuating treatment media 420.

[0042] While a preferred humectant is sorbitol, other humectants, including glycerin, propylene glycol, a longer chain glycol, an acrylic polymer humectant or gellant, and/or calcium chloride can be used. As previously indicated, the infectious agent attenuator solution from which the infectious agent attenuator 424 is produced can be made of a formulation that includes one or more wetting agents, one or more viscosity modifiers and/or stabilizers, one or more pH modifiers and/or stabilizers, one or more surfactants, such as rhamnose lipid(s) surfactants or rhamnolipid biosurfactants, as well as one or more other constituents or components. Where the formulation of the attenuator solution includes one or more of these other components or constituents, the total amount of such one or more of these additional components or constituents makes up no more than 10% of the attenuator solution by solution weight, preferably no more than 5% of the attenuator solution by weight, more preferably no more than about 2.5% of the attenuator solution by weight, at the time of application of the attenuator solution to the air filtering material layer 423 to produce the infectious agent attenuating or inactivating air treatment media 420 containing infectious agent attenuator 424, preferably infectious agent attenuator gel 427, upon suitable drying. Where the formulation of the attenuator solution includes one or more of these other components or constituents, the total amount of such one or more of these additional components or constituents present in the attenuator 424, preferably attenuator gel 427, of the air treatment media 420 makes up no more than 10% of the attenuator 424, preferably attenuator gel 427, by weight, preferably no more than 5% of the attenuator 424, preferably attenuator gel 427, by weight, more preferably no more than about 2.5% of the attenuator 424, preferably attenuator gel 427, by weight.

[0043] A preferred formulation of the infectious agent attenuator solution and attenuator 424 may further include a surfactant to facilitate more uniform application of the infectious agent attenuator solution to the air filtering material layer 423 producing an air-filtering infectious agent attenuating treatment media 420 with the attenuator 424, preferably attenuator gel 427, more uniformly distributed throughout the resultant air treatment media 420. In such a preferred infectious agent attenuator solution and attenuator 424 containing a surfactant, the surfactant remains present in the attenuator 424, preferably attenuator gel 427, uniformly distributed throughout the air treatment media 420 and facilitates attenuation or inactivation of infectious agents like viruses such as the SARS-COV2 coronavirus by causing the infectious agents in the air flowing through the media 420 to be more readily attracted to exposed surface of the attenuator 424, preferably attenuator gel 427. In such a preferred infectious agent attenuator solution and attenuator 424 containing a surfactant, the surfactant remains present in the attenuator 424, preferably attenuator gel 427, uniformly distributed throughout the air treatment media 420 and facilitates attenuation or inactivation of infectious agents like viruses such as the SARS-COV2 coronavirus by attracting and encapsulating the infectious agents in the air flowing through the media 420 in the attenuator 424, preferably attenuator gel 427, of the media 420.

[0044] Where a surfactant is used, at least one drop of surfactant is added to the infectious agent attenuator solution producing an infectious agent attenuator solution having between 0.001% and 0.1% of surfactant by weight of the solution. In one infectious agent attenuator formulation and solution that made with a surfactant, the solution and the attenuator, including attenuator gel, which results after application and drying of the solution contains between 0.001% and 0.1% of surfactant by weight. In another infectious agent attenuator formulation and solution that contains surfactant, the solution and attenuator that results after application and drying of the solution contains between 0.01% and 1% of surfactant by weight. The inclusion of the surfactant not only reduces surface tension during application, preferably impregnation, by enabling the solution to wick along the fibers and filaments of the filtering material layer 423 more uniformly impregnating the layer 423 therewith producing a more uniform attenuator and gel throughout the resultant air treatment media 420 produced but the surfactant acts on viruses and bacteria in droplets and the like flowing through the media 420 by lysing them destroying the viruses and bacteria contacting the surfactant containing attenuator and attenuator gel lining the air flow passages of the media 420.

[0045] In the making of infectious agent attenuating or inactivating air treatment media 420, a filtering material layer 423 can be treated by dipping the filtering material layer 423 into a container of the infectious agent attenuator solution to dip coat the filtering material layer 423 with the solution thereby impregnating the filtering material layer 423 therewith and which is removed from the solution and dried, such as by oven and/or convection drying, to produce an infectious agent attenuating air treatment media 420 of the present invention containing or configured with congealed or solidified infectious agent attenuator 424 exposed to air flowing therethrough that is ready for use in a personal protective air filtering device 422 like a surgical mask, respirator, or another type of personal protective equipment (PPE). The filtering material layer 423 can also be treated by spraying the infectious agent attenuator solution onto the layer 423, such as by using an air spray or air sprayer, a high volume, low pressure (HVLP) spray or sprayer, a low volume, medium pressure (LVMP) spray or sprayer, an airless spray or airless sprayer, an air-assisted airless spray or airless sprayer, or an electrostatic applicator, such as an air spray electrostatic spray or sprayer, an air-assisted airless spray electrostatic spray or sprayer, or rotary atomization electrostatic spray or sprayer, thereby coating and preferably impregnating the layer 423 therewith producing an infectious agent attenuating air treatment media 420 of the present invention containing or configured with congealed or solidified infectious agent attenuator 424 exposed to air flowing therethrough.

[0046] When the filtering material layers 423 are treated, the density or thickness of the untreated filtering material 423A increases as compared to the density of the treated filtering material 423b. As seen in FIGS. 1 and 2, when the filtering material layer 423 is treated, the filtering material layer 423 increases in density and minimizes the pores, holes, or airflows within the filtering material 423 through coating the fibers or strands filtering material 423 by increasing the diameter of the fibers. FIG. 1 compares the untreated edge of the filtering material 423a to the treated edge of the filtering material 423b Similarly, FIG. 2 compares the face of the untreated filtering material 423a to the treated filtering material 423b. As seen in FIGS. 1 and 2, the treated filtering material 423b is substantially denser than the untreated filtering material 423a. Thus, the treated filtering material 423b increases the likelihood that infectious agents will contact and adhere to the filtering material 423 and also reduces the likelihood that infectious agents will pass through the filtering material 423 when compared to the untreated filtering material 423a.

[0047] A preferred layer of infectious agent attenuating or inactivating filter media 420 has an antiviral efficacy of at least 1.3, preferably at least 1.5, more preferably at least 2.0, when tested for antiviral activity using a human coronavirus in accordance with ISO Test Standard 18184 for a contact time of 10 minutes and showed no bacterial growth of Staphylococcus aureus and Klebsiella pneumonia when the infectious agent attenuating or inactivating filter media 420 was placed in a triptych soy agar or nutrient agar-containing petri dish in accordance with test standard AATCC TM147-2011(2016)e—Test Method for Antibacterial Activity of Textile Materials.

[0048] With continued reference to FIGS. 4-7, the present invention is further directed to a personal protective air filtering device 422 made with such an infectious agent attenuator impregnated air treatment media 420 impregnated with infectious agent attenuator 424 composed of acid-based biocide and humectant in an aqueous carrier and which can be formulated as a gel, e.g., a hydrogel, or to form a gel, e.g., hydrogel, which retains enough moisture after application to the treatment media 420 to keep the acid-based biocide moisturized and at or within a desired pH range or pH that keeps the biocide activated and effective. A preferred attenuator formulation is configured as a flowable liquid, e.g., attenuator solution, sprayed onto the treatment media 420, e.g., applied with a spray applicator, dripped onto the treatment media 420, e.g., applied with a spray applicator, misted onto the treatment media 420, e.g., applied with a misting applicator or mister, fogged onto the treatment media 420, e.g., applied with a fogging applicator or fogger, bubbled onto the treatment media 420, e.g., applied with a bubble applicator or bubble generator, and/or applied by dipping the treatment media 420 into a container, e.g., tank or vat, containing the liquid attenuator, e.g., liquid attenuator solution. The applied liquid attenuator is configured or formulated to spread via wetting, wicking and/or capillary action into a hard-surfaced fibrous mesh of the treatment media 420 substantially uniformly distributing attenuator within and throughout the treatment media 420. Such an attenuator is further configured or formulated to increase in viscosity upon or after application to the treatment media 420 until it gels and/or forms a gel that forms an attenuator coating or lining that adheres to the hard surfaces of the mesh of the treatment media 420 thereby impregnating the treatment media 420 with attenuator.

[0049] The personal protective air filtering device 422 is a body-worn personal air filtering apparatus 427, preferably a personal air purification filter mask 428, configured to be body worn, by being configured for being removably mounted to or on a head of a person in a manner that positions the infectious agent attenuator impregnated air treatment media 420 in air flow communication with a mouth and/or nose of the person wearing the air treatment device 422 or air filtering apparatus 427 so infectious agents in air flowing through the treatment media 420 are attenuated or inactivated by biocide in attenuator impregnated into the treatment media 420. In a preferred embodiment and method, the personal air filtering device 422 has a mounting arrangement 430 constructed and arranged to removably mount the device 422 onto the head of a person using a head strap, harness, ear loops or another type of mounting arrangement that positions the treatment media 420 adjacent to, inline and preferably overlying the mouth or nose of the person wearing it so inhaled air flows through the treatment media 420 before entering the nose or mouth of the person. In such a preferred embodiment and method, ambient air, such as air in a room or outdoors, flows through the treatment media 420 of the personal air filtering device 422 worn by the person during inhalation by a pressure differential between the ambient air and air in a pocket between the treatment media 420 and mouth of the person created by or during inhalation of the person. In such a preferred embodiment and method, a person wearing the personal air treatment device 422 is the air mover responsible for moving air through the treatment media 420 during inhalation. If desired, the personal air treatment device 422 can be equipped with or otherwise configured with one or more exhalation valves that route exhaled air around the treatment media 420 during exhalation. If desired, the personal air treatment device 422 can be equipped with or otherwise configured with one or more exhalation miniature fans or blowers cause air to flow through the treatment media 420 to the person's mouth and/or nose during use and operation.

[0050] The personal air filtering device 422 has a mounting arrangement 430 configured for removably mounting the device 422 onto the head of a person, which can be in the form of a strap, e.g., head strap, band, e.g., adjustable head band, a harness, e.g., adjustable harness, one or more loops, e.g., ear loops, or the like. In the preferred but exemplary air filtering device 422 shown in FIGS. 6 and 7, the mounting arrangement 430 is a head-mounted harness 432 with a plurality of straps 482 and releasable hook-and-loop fastener closure configured to be received and retained around a rear portion of the head, e.g., around a rear portion of the skull, and/or neck of a person wearing the device 422. The mounting arrangement 430, e.g., harness 432, can be of an adjustable configuration and/or elastic construction to enable location and fitment of an air treatment media carrier 434 in air flow communication with the nose and/or mouth of a person wearing the device 422.

[0051] The air treatment media carrier 434 is configured to carry the infectious agent attenuator impregnated air treatment media 420 and locate the treatment media 420 so the treatment media 420 is generally inline with, overlies and is disposed in air flow communication with the nose and/or mouth of a person wearing the air treatment device 422 during air disinfecting use and operation of the device 422. In the embodiment shown in FIG. 5, the air treatment media carrier 434 includes an infectious agent attenuator impregnated air treatment media structural support assembly 436, such as in the form of a concave housing 438, e.g., perforate concave outer plastic shell 440, which mates with a concave perforate structural support frame 442 equipped with a inner peripheral face seal 445 and carries and/or structurally supports the infectious agent attenuator impregnated air treatment media 420 therebetween. Where of multilayer construction, the air treatment media structural support assembly 436 also supports any other perforate or porous flow through material, e.g., filter material or filter layers, e.g., additional layer(s), disposed inline upstream and/or downstream of the air treatment media 420. Where of multilayer construction, the air treatment media 420 and layer(s) of filter media are removably captured between the outer housing 438 and inner support frame 442. The personal air filtering device 422 can also include one or more valves 447, such as bypass valves and/or exhaust valves configured to allow air exhaled from a person wearing the personal air filtering device 422 to be exhausted and can be configured to do so without having to pass back through the treatment media 420 as well as having to flow through any other perforate or porous flow through material, e.g., filter material or filter layers, disposed inline with the treatment media 420 during exhalation.

[0052] The personal air filtering device 422 has at least one layer of infectious agent attenuator impregnated air treatment media 420 disposed between an ambient air source, e.g., room air, and the mouth and/or nose of a person wearing the device 422 for attenuating or inactivating infectious agents in air being drawn through the device 422 during inhalation by the person. The treatment media 420 of the personal air filtering device 422 is made of a perforate material, such as a perforate mesh material, woven material, nonwoven material, or another type of perforate and/or porous material that can be a hard-surfaced air treatment media material like that disclosed above with regards to the treatment media embodiments. Such a perforate air treatment media material can be a woven material, nonwoven material, or other type of perforate and/or porous material, which can be and preferably is of water-impervious construction, e.g., made of a perforate or porous material impervious to water. Such a perforate or porous air treatment media material, woven material, nonwoven material, or another type of perforate and/or porous material can be and preferably also is of reusable and/or washable construction, e.g., made of a washable material and/or a reusable material. Such a material can be a melt-blown material, a spunbound material, cotton, or another type of woven or nonwoven porous and/or perforate material.

[0053] With reference once again to FIG. 5, the treatment media 422 can be used in a multilayer filter mask 445, such as a multilayer surgical mask or more preferably an N-95, N-99, KN-95 or KN-99 respirator 446 having a perforate air filtering and treatment assembly 458 with at least a plurality of pairs of perforate, porous or flow-through layers 500, 502, 504, 506 and/or 508 with at least one of the layers being a particulate filter layer, preferably a plurality of the layers being particulate filtering layers, and at least one of the layers that is or composed of an infectious agent attenuator impregnated air treatment media 420. In an exemplary embodiment, the air filtering and treatment assembly 458 has at least one inner layer 452 that is an infectious agent attenuator impregnated air treatment media 420 sandwiched between at least a pair of air filter layers and preferably sandwiched between a plurality of pairs of air filter layers 500, 504 and 504, 508, such as is depicted in FIG. 5. Any of the layers can be made of any of the filter materials and/or air treatment media materials discussed elsewhere herein.

[0054] In at least one embodiment, the filter media 420, preferably at least one layer of filter media 420, where of multilayer construction, is made of such a perforate material, preferably perforate mesh material, configured not only to receive and carry infectious agent attenuator, but also or includes a perforate particulate filter material configured to filter and trap particulates, aerosols and/or droplets during personal filtering device use and operation. The personal air filtering device 422 can also include one or more additional layers of perforate or porous flow through material not treated or impregnated with infectious agent attenuator disposed in air flow communication with, preferably inline with, and more preferably overlapping at least one layer of the infectious agent attenuator impregnated air treatment media.

[0055] Where the personal air filtering device 422 is constructed with one or more such additional perforate flow through material layers not carrying or being impregnated with infectious agent attenuator, each such layer can be composed of an air filtering material, e.g., comprise an air filtering layer, not treated or impregnated with infectious agent attenuator, but which is configured (a) to filter particulates, aerosols, and/or droplets, (b) as a moisture barrier, (c) as a vapor barrier, (d) as an electrostatic filter media, (e) as another type of filter or filter media, and/or (f) as another type of flow-through layer disposed either or both upstream and/or downstream of at least one layer of the infectious agent attenuator impregnated air treatment media. Where one or more such additional layers are present, one or more of the additional layers can be composed or constructed of one or more of the hard-surfaced air treatment media materials of the air treatment system disclosed above but not containing, treated with nor impregnated with attenuator 424.

[0056] A preferred infectious agent attenuator used in the infectious agent attenuator impregnated air treatment media 420 is composed of a biocide that preferably is an acid-based biocide in combination with a humectant configured to retain moisture, e.g., water, to keep the biocide moisturized and at a desired pH, preferably no more than about 3 pH, or within a suitable pH range of between 0 and 5 pH, preferably between 0-4 pH, and more preferably between 0-3 pH. A preferred acid-based biocide is composed of a carboxylic acid, preferably citric acid, in a strength and pH suitable for disinfecting air coming in contact with such an acid-based or acid-containing attenuator by attenuating or inactivating infectious agents in the air including by denaturing the infectious agents. A preferred attenuator is in the form of a gel, such as a hydrogel, which defines a matrix, a gel matrix or hydrogel matrix, in which one or both the biocide and humectant are disposed and which adheres to the air treatment media. In a preferred embodiment, the gel or at least part of the gel is formed of the humectant, which can be a gel forming humectant or gellant, with the gel forming the matrix, e.g., gel matrix or hydrogel matrix, in which the biocide is relatively uniformly, preferably substantially uniformly, distributed.

[0057] When such an infectious agent attenuator gel is applied onto the treatment media 420, the gel coats or lines hard surfaces within the treatment media that define air flow paths therethrough thereby exposing biocide within the gel to infectious agents in the air flowing through the treatment media 420 during personal air filter device use and operation. Where the treatment media 420 is a perforate or porous filter fabric, such as of woven, nonwoven and/or fibrous construction, infectious agent attenuator in a liquid form is applied thereto with the composition of the infectious agent attenuator configured to cause the infectious agent attenuator to gel up upon or after application forming a gel, i.e., infectious agent attenuator gel, which becomes impregnated into the perforate or porous filter material of the filter media 420.

[0058] An infectious agent attenuator impregnated treatment media 420 made with such an infectious agent attenuator formulation, particularly an infectious agent attenuator gel formulation, and a personal protective filter device 422 having at least one infectious agent attenuating air treatment layer, preferably filter layer, of a treatment media 422 made of such an infectious agent attenuator formulation, particularly an infectious agent attenuator gel formulation, is of regenerable construction after being used for a period of time by application thereto of a regenerating fluid that preferably is an aqueous liquid regenerating solution. Such an aqueous liquid regenerating solution contains water and wets the infectious agent attenuator, preferably infectious agent attenuator gel, impregnated into the treatment media 420 when the aqueous liquid regenerating solution is applied to the treatment media 420. Wetting the infectious agent attenuator, preferably infectious agent attenuator gel, impregnated into the treatment media 420 with an aqueous regeneration fluid increases the moisture content of the infectious agent attenuator, preferably infectious agent attenuator gel, thereby regenerating it by the increased moisture content changing its pH, preferably increasing its pH, so its pH is within a range of between 4 and 7 pH, preferably between about 5 and 6 pH, and more preferably about 5.5 pH. Regenerating the infectious agent attenuator, preferably infectious agent attenuator gel, by remoisturizing it to increase its moisture content after treatment media and/or a personal protective filter device use advantageously enables the treatment media 420 and personal protective filter device 422, 422′ made with such an attenuator impregnated or attenuator gel impregnated treatment media 420 to be reused over and over again. In other words, a regeneration cycle or regeneration can be performed at least a plurality of pairs of, i.e., at least three, times to regenerate the treatment media 420 of the device 422 at least a plurality of pairs of, i.e., at least three, times. During regeneration, water in the aqueous regenerating fluid wetting an attenuator gel not only wets and moisturizes biocide in the gel to regenerate the biocide by returning its pH within an aforementioned desired pH range and/or at about a desired pH, but water is absorbed by the gel, preferably absorbed into the gel matrix, that keeps the biocide in the gel moist and within an aforementioned desired pH range and/or at about a desired pH. In one preferred formulation, the aqueous regenerating fluid is a liquid composed substantially completely of water.

[0059] In another preferred embodiment and regeneration method where the treatment media 420 is impregnated with an infectious agent attenuator gel, the regeneration fluid preferably is a replenishing fluid containing biocide in an aqueous solution applied onto the infectious agent attenuator gel impregnated treatment media.

[0060] The applied regeneration fluid wets the treatment media and wets the infectious agent attenuator gel impregnated into the treatment media replenishing the gel impregnated into the treatment media with biocide lost, e.g., via neutralizing reaction, evaporation, sublimation, etc. during treatment media and/or personal protective filter mask use and operation. When wetted by such a biocide-containing aqueous replenishing fluid, water in the fluid advantageously substantially simultaneously regenerates biocide remaining in the gel by moisturizing it, thereby maintaining disinfecting efficiency by keeping it within an aforementioned desired pH range or pH. When wetted by such a biocide-containing aqueous replenishing fluid, biocide in the fluid is advantageously absorbed by the gel and retained within the gel during treatment media and personal protective filter mask use and operation increasing the amount and exposed surface area of biocide available to attenuate or inactivate infectious agents.

[0061] A preferred air breath moisture activated and regenerated infectious agent attenuating mask of the present invention has an air filtering layer of the mask that is or includes a layer of infectious agent attenuating or inactivating filter media 420 with an antiviral efficacy of at least 1.3, preferably at least 1.5, more preferably at least 2.0, when tested for antiviral activity using a human coronavirus in accordance with ISO testing standard 18184 for a contact time of 10 minutes and showed no bacterial growth of Staphylococcus aureus and Klebsiella pneumonia when infectious agent attenuating or inactivating filter media 420 was placed in a triptych soy agar or nutrient agar —containing petri dish in accordance with test standard AATCC TM147-2011(2016)e—Test Method for Antibacterial Activity of Textile Materials.

[0062] In a preferred embodiment, the personal air filtering device 422 is a three-layer, four-layer or five layer surgical mask having at least one layer composed of an infectious agent attenuator impregnated air treatment media made in accordance with the following specifications:

[0063] Hypoallergenic Safe & Comfort

[0064] 3 extra thick ply with ear loops

[0065] Bacterial Filtration Efficiency or B.F.E>95%

[0066] Particle Filtration Efficiency or P.F.E>95%

[0067] Manufactured under ISO 9001 and/or meets ISO 9001

[0068] Has a water repellent top/outer & base/inner layer

[0069] Made with layers of Fiberglass-free filter medium

[0070] Outer layer—Hydrophobic non-woven layer

[0071] Middle layer—Meltblown filter

[0072] Inner layer—Soft absorbent layer

[0073] Adjustable nose bridge

TABLE-US-00001 Characteristic N95 Bacterial filtration efficiency ≥95% Sub-micron particulates filtration efficient at 0.3 micron ≥95% Differential pressure, mm H20/cm2 (Breathability) <5.0 Resistance to penetration by synthetic blood, the minimum 160 mm Hg pressure in mm Hg for pass result

[0074] The present invention also is directed to an infectious agent attenuating or inactivating personal protective equipment device, such as a surgical mask, multilayer mask or respirator having at least one porous filtering layer impregnated with an infectious agent attenuating or inactivating solution that tries to leave behind an infectious agent attenuating or inactivating attenuator composed of an organic acid that preferably is citric acid, a humectant that preferably is a gelling humectant that preferably is sorbitol which produces or forms a self activating or self replenishing infectious agent attenuator gel and infectious agent attenuating and inactivating air treatment media having a pH of no greater than 5, preferably no greater than 4 and more preferably no greater than 3.5 which is kept moist and activated at or below the desired pH by moisture in the breath of a person wearing the mask. The solution can include a surfactant, such as preferably a rhamnolipid biosurfactant that reduces surface tension both during impregnation of the solution thereby more uniformly impregnating the solution into the at least one porous filtering layer producing an air treatment media having infectious agent attenuating gel more uniformly distributed throughout. The surfactant remains in the gel and reduces surface tension of aerosols and droplets containing viruses and bacteria entrained in the air flowing through the air treatment media contacting the infectious agent attenuating gel more rapidly and efficiently attenuating or inactivating the viruses and bacteria preferably with the reduced surface tension produced by the inclusion of the surfactant also destroying them by lysing the viruses and bacteria.

[0075] Understandably, the present invention has been described above in terms of one or more preferred embodiments and methods. It is recognized that various alternatives and modifications may be made to these embodiments and methods which are within the scope of the present invention.