WO2021185365A1

WO2021185365A1 - Method and apparatuses for a multi-layered or multifaceted system for deactivating airborne particles

Info

Publication number: WO2021185365A1
Application number: PCT/CN2021/081856
Authority: WO
Inventors: Hong Huan HOR; Wei Shen AIK; Kok Wai Cheah; Keng Tiong Tan
Original assignee: Hong Kong Baptist University
Priority date: 2020-03-19
Filing date: 2021-03-19
Publication date: 2021-09-23
Also published as: TW202140083A

Abstract

An assembly to inactivate microbes in air flowing there through comprising an indirect air flow pathway, wherein the indirect air flow pathway comprises micro structures, micro cilia or meshes; wherein in the indirect air flow pathway a plurality microbial deactivation apparatuses are disposed. The plurality microbial deactivation apparatuses comprise at least one UV radiation apparatus (130), at least one physical nanometal oxide or nanometal apparatus (140), at least one negative ion apparatus (120), at least one temperature raising apparatus, at least one chemical oxidizer apparatus (150) and at least one organic antimicrobial apparatus (160). The assembly is effective in deactivation and removal of airborne particles, microbes, nanoparticles, gaseous and toxins.

Description

Method And Apparatuses For A Multi-layered Or Multifaceted System For Deactivating Airborne Particles

Inventors: HOR, Hong Huan; AIK, Wei Shen; CHEAH, Kok Wai; TAN, Keng Tiong

CROSS REFERENCE OF RELATED APPLICATION

This application claims the benefit of priority of United States Provisional Patent Application Serial Number 62/992,134 filed on March 19, 2020, which is hereby incorporated by reference in its entirety for all purposes.

FIELD OF THE INVENTION

The present invention relates to method and apparatuses for a multi-layered or multifaceted system for deactivating hazardous airborne particles. In particular, the present invention relates to method and apparatus for a multifaceted system for deactivating airborne particles that is effective in deactivation and removal of airborne particles, microbes, nanoparticles, gaseous and toxins. One embodiment of the present invention is lightweight, compact and can be active or passive in operation, allowing effective and efficient operation for prolonged periods of time. Another embodiment of the present invention can be sterilized, cleaned and reused. Yet another embodiment of the present invention is environmentally friendly and non-toxic to human. It has potential to be developed into air filters, facial masks, surgical masks and respirator systems.

BACKGROUND OF THE INVENTION

Filtration systems for removing airborne particles, microbes, nanoparticles, gaseous and toxins have well developed for many years. These conventional systems are generally divided into wearable and non-wearable systems. For conventional wearable systems, these are also generally divided into active and passive systems. For such wearable systems, there is often a trade-off between an effective system and comfort to the wearer. Most of the conventional wearable systems use a physical barrier as a means to filter out the airborne particles, microbes, nanoparticles, gaseous and toxins. Some of the conventional wearable systems also use a physical or a chemical means to deactivate the airborne particles, microbes, nanoparticles, gaseous and toxins. A few of these conventional wearable systems can also be sterilized, cleaned and reused.

Nonetheless, none of the conventional wearable systems can provide a functionally effective, efficient and reusable system that is both safe and comfortable for the wearer for a prolonged periods of time. It is an objective of the present invention to provide such a solution with different embodiments of the present invention.

SUMMARY OF THE INVENTION

Accordingly, the objective of the present invention relates to method and apparatuses for a multi-layered or multifaceted system for deactivating hazardous small particles. In particular, the present invention relates to method and apparatuses for a multi-layered or multifaceted system that is effective in deactivation and removal of hazardous small particles including airborne particles, microbes, nanoparticles, gaseous and toxins. One embodiment of the present invention is lightweight, compact and can be active or passive in operation, allowing effective and efficient operation for prolonged periods of time. Another embodiment of the present invention can be sterilized, cleaned and reused. Yet another embodiment of the present invention is environmentally friendly and non-toxic to human. It has potential to be developed into air filters, facial masks, surgical masks and respirator systems.

In a first aspect of the present invention, there is provided an assembly to inactivate microbes in air flowing therethrough comprising:

an indirect air flow pathway in said assembly, wherein the air flow in a direction from an air inlet opening of the assembly to flow out via an air outlet of the assembly, wherein said indirect air flow pathway comprises micro structures, micro cilia or meshes such that the air flowing through said assembly is in contact at least once on said micro structures, micro cilia or meshes while the air flow remains constant in terms of quantity and velocity thereof;

wherein in the indirect air flow pathway a plurality microbial deactivation apparatuses is disposed, comprising at least one UV radiation apparatus, at least one physical nanometal oxide or nanometal apparatus, at least one negative ion apparatus, at least one temperature raising apparatus, at least one chemical oxidizer apparatus and at least one organic antimicrobial apparatus, wherein the microbial deactivation apparatus closest to the air inlet opening of the assembly is the at least one UV radiation apparatus or the at least one negative ion apparatus, and wherein the at least one physical nanometal oxide or nanometal apparatus and the at least one UV radiation apparatus are disposed in the same section of the indirect air flow pathway in said assembly, and

wherein said assembly has an air volume capacity of at least 300 ml.

In a first embodiment of the first aspect of the present invention, the at least one UV radiation apparatus is a UV-C radiation LED source.

In a second embodiment of the first aspect of the present invention, the at least one physical nanometal oxide or nanometal apparatus is at least one micro structure, micro cilia or mesh coated with at least one nanofilm of TiO ₂.

In a third embodiment of the first aspect of the present invention, the at least one negative ion apparatus is also a UV radiation apparatus.

In a fourth embodiment of the first aspect of the present invention, the at least one organic antimicrobial apparatus is a detergent.

A second aspect of the present invention provides an active or a passive air purification system comprising the assembly according to any one of the embodiments in the first aspect or any other related embodiment described herein.

A third aspect of the present invention provides an air purification system comprising the assembly according to any one of the embodiments in the first aspect or any other related embodiment described herein which are configured into either a multifaceted or multi-layered structure, or a combination thereof.

A fourth aspect of the present invention provides a breathing apparatus to inactivate microbes in air flowing therethrough comprising:

an indirect air flow pathway in said breathing apparatus wherein the air flow in a direction from an air inlet opening of the breathing apparatus to flow out via an air outlet of the breathing apparatus, wherein said indirect air flow pathway comprises micro structures, micro cilia or meshes such that the air flowing through said breathing apparatus is in contact at least once on said micro structures, micro cilia or meshes while the air flow remains constant in terms of quantity and velocity thereof;

wherein in the indirect air flow pathway a plurality of microbial deactivation apparatuses is disposed, comprising at least one UV radiation apparatus, at least one physical nanometal oxide or nanometal apparatus, at least one negative ion apparatus, at least one temperature raising apparatus, at least one chemical oxidizer apparatus and at least one organic antimicrobial apparatus, wherein the microbial deactivation apparatus closest to the air inlet opening of the breathing apparatus is the at least one UV radiation apparatus or the at least one negative ion apparatus, and wherein the at least one physical nanometal oxide or nanometal apparatus and the at least one UV radiation apparatus are arranged in the same section of the indirect air flow pathway in said breathing apparatus, and

wherein said breathing apparatus has an air volume capacity of at least 300 ml.

In a first embodiment of the fourth aspect of the present invention, the at least one UV radiation apparatus is a UV-C radiation LED source.

In a second embodiment of the fourth aspect of the present invention, the at least one physical nanometal oxide or nanometal apparatus is at least one micro structure, micro cilia or mesh coated with at least one nanofilm of TiO ₂.

In a third embodiment of the fourth aspect of the present invention, the at least one negative ion apparatus is a UV radiation apparatus.

In a fourth embodiment of the fourth aspect of the present invention, the at least one organic antimicrobial apparatus is a detergent.

A fifth aspect of the present invention provides an active or a passive air purification system comprising the breathing apparatus according to any one of the embodiments in the fourth aspect or any other related embodiment described herein.

A sixth aspect of the present invention provides an air purification system comprising the breathing apparatus according to any one of the embodiments in the fourth aspect or any other related embodiment described herein which are configured into a multifaceted or multi-layered structure, or a combination thereof.

A seventh aspect of the present invention provides an attachment to a breathing apparatus which inactivates microbes in the air flowing therethrough comprising:

an indirect air flow pathway in said attachment wherein the air flow in a direction from an air inlet opening of the breathing apparatus to flow out via an air outlet of the breathing apparatus, wherein said indirect air flow pathway comprises micro structures, micro cilia or meshes such that the air flowing through said attachment is in contact at least once on said micro structures, micro cilia or meshes while the air flow remains constant in terms of quantity and velocity thereof, and

wherein in the indirect air flow pathway, a plurality of microbial deactivation apparatuses is disposed, comprising at least one UV radiation apparatus, at least one physical nanometal oxide or nanometal apparatus, at least one negative ion apparatus, at least one temperature raising apparatus, at least one chemical oxidizer apparatus and at least one organic antimicrobial apparatus, wherein the microbial deactivation apparatus closest to the air inlet opening of the breathing apparatus is the at least one UV radiation apparatus or the at least one negative ion apparatus, and wherein the at least one physical nanometal oxide or nanometal apparatus and the at least one UV radiation apparatus are disposed in the same section of the indirect air flow pathway in said attachment, and

wherein said attachment has an air volume capacity of at least 300 ml.

Other aspects of the present invention include a breathable device comprising one or more of the assemblies according to any one of the embodiments in the first aspect or any other related embodiment described herein, and at least one of an active and a passive air flow and purification assemblies for wearer of said breathable device to inhale and exhale air without air flow blockage while hazardous small particles including airborne particles, microbes, nanoparticles, gaseous and toxins from inhaled air are deactivated and removed by physical and chemical inactivation mechanisms provided by said one or more breathing apparatuses prior to reaching a respiratory system of the wearer.

Yet other aspects of the present invention include a respirator comprising one or more of the assemblies according to any one of the embodiments in the first aspect or any other related embodiment described herein, which are arranged to maximize exposure surface area of the one or more assemblies to one or more compartments of the respirator where air flows from at least an air inlet to at least an outlet of the respirator through the one or more compartments such that deactivation and removal of hazardous small particles including airborne particles, microbes, nanoparticles, gaseous and toxins in air from the air inlet by physical and chemical inactivation mechanisms of the breathing apparatuses is maximized while quantity and velocity of the air flowing through the respirator remain constant.

Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described.

The present invention includes all such variation and modifications. The invention also includes all of the steps and features referred to or indicated in the specification, individually or collectively, and any and all combination or any two or more of the steps or features.

Throughout the present specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising" , will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. It is also noted that in this disclosure and particularly in the claims and/or paragraphs, terms such as “comprises” , “comprised” , “comprising” and the like can have the meaning attributed to it in U.S. Patent law; e.g., they can mean “includes” , “included” , “including” , and the like; and that terms such as “consisting essentially of” and “consists essentially of” have the meaning ascribed to them in U.S. Patent law, e.g., they allow for elements not explicitly recited, but exclude elements that are found in the prior art or that affect a basic or novel characteristic of the present invention.

Furthermore, throughout the present specification and claims, unless the context requires otherwise, the word “include” or variations such as “includes” or “including” , will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Other definitions for selected terms used herein may be found within the detailed description of the present invention and apply throughout. Unless otherwise defined, all other technical terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the invention belongs.

Other aspects and advantages of the present invention will be apparent to those skilled in the art from a review of the ensuing description.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the present invention will become apparent from the following description of the invention, when taken in conjunction with the accompanying drawings, in which:

Figure 1 shows a multi-layered air purification system.

Figure 2 shows a multi-faceted air purification system.

Figure 3 shows an active air purification system.

Figure 4 shows a passive air purification system.

Figure 5 shows an inner structure of an embodiment of the canister of the present invention.

Figure 6 shows an embodiment of the air purification system of the present invention.

Figure 7 shows the OD vs time effects of UV-C radiation on E. coli from a 1 cm distance.

Figures 8A &8B show the OD vs radiation distance effects of UV-C radiation on E. coli for a duration of 6 seconds.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is not to be limited in scope by any of the specific embodiments described herein. The following embodiments are presented for exemplification only.

One objective of the present invention relates to method and apparatuses for a multi-layered or multifaceted system for deactivating hazardous small particles. In particular, the present invention relates to method and apparatuses for a multi-layered or multifaceted system that is effective in deactivation and removal of hazardous small particles including airborne particles, microbes, nanoparticles, gaseous and toxins. One embodiment of the present invention is lightweight, compact and can be active or passive in operation, allowing effective and efficient operation for prolonged periods of time. Another embodiment of the present invention can be sterilized, cleaned and reused. Yet another embodiment of the present invention is environmentally friendly and non-toxic to human. It has potential to be developed into air filters, facial masks, surgical masks and respirator systems.

It is another objective of the present invention that such a multi-layered or multifaceted system is comfortable for the wearer to wear and use for prolonged periods of time. To achieve all the desired objectives of the present invention, it is imperative that the desired performance characteristics of the present invention is clearly identified and achieved in the present invention.

Parameters of the problem to be solved

The major problem to be solve by the present invention are comprising of the following aspects for the user of the various embodiments of the present invention:

1. ) Safety and fit for purpose.

The purpose of the present invention is to effectively deactivate and remove airborne particles, microbes, nanoparticles, gaseous and toxins from the air inhaled by the users of the present invention. Each of these hazardous material and medium has different characteristics and can be deactivated and/or removed by different means.

One of the many hazardous airborne particles to be removed from air inhaled by the users of the present invention are airborne viruses. Such viruses are generally ranging in size from 5 to 300 nanometres (nm) . Such viruses are generally comprise of a protein based and/or lipid based outer shell. Moreover, viruses are particles and do not have any means of self-mobility. Airborne viruses are often made airborne via exhalation from an infected host. These viruses are often carried in such exhalation aerosols and/or droplets. Such exhalation aerosols and/or droplets range from 0.1 –900 microns (μm) in size. Other than viruses, another type of airborne hazardous material is microbes, which comprise of bacterial and fungal spores. The average size of most bacteria is between 0.2 to 2.0 microns (μm) . Such bacteria also generally comprise of a protein based and/or lipid based outer shell. Bacteria can also be categorized into Gram positive bacteria and Gram negative bacteria. Gram positive bacteria have a thick peptidoglycan layer and no outer lipid membrane whilst Gram negative bacteria have a thin peptidoglycan layer and have an outer lipid membrane. Fungal spore size varies among species from 5 microns (μm) to over 50 microns (μm) in size. Other hazardous materials in the air comprise of nanoparticles, for example harmful particulate matter (PM) . These are often categorized into PM 2.5 and PM 10. PM 2.5 are particulate matters with an aerodynamic diameter less than or equal to a nominal 2.5 microns (μm) while PM 10 are particulate matters with an aerodynamic diameter less than or equal to a nominal 10 microns (μm) . PM 1.0 are particulate matters with an aerodynamic diameter less than or equal to a nominal 1 microns (μm) . Such particulate matters often comprise of mixture of fine airborne solid particles and liquid droplets (aerosols) include components of chemicals such as nitrates, sulphates, elemental carbon, organic carbon compounds, acid aerosols, trace metals, and geological material. Some aerosols are formed in the atmosphere from gaseous combustion by-products such as volatile organic compounds (VOCs) , oxides of sulphur (SOx) and nitrogen oxides (NOx) . Other hazardous materials in the air also comprises of noxious gases, allergens and airborne toxins that are harmful to human beings. To be considered safe and fit for purpose, embodiments of the present invention must be able to effectively and efficiently remove these hazardous materials from the air and/or render them harmless to the users inhaling such air.

2. ) Comfort for the user in using the various embodiments of the present invention for prolonged periods of time.

One embodiment of the present invention is lightweight, compact and can be active or passive in operation, allowing effective and efficient operation for prolonged periods of time. This is to allow the user of such an embodiment to comfortably use the present invention for a prolonged period of time.

For user’s comfort when used as a breathing apparatus, the embodiment of the present invention must allow free flow of air for breathability of the user. For breathability of the user, it is commonly specified the required airflow for different situations for an adult human are as follows: sleeping requires 6 L/min, walking 14-26 L/min and maximum exertion 65-100 L/min. Thus, for user’s comfort the embodiment of the present invention must allow airflow of such capacities. Furthermore, as some embodiments of the present invention are also wearable thus, they must be also comfortable in weight and fitting for the user. Comparative respirators in the market do not exceed a maximum net weight of 500 grams. Moreover, for comfort and safety, the embodiments of the present invention must have a snug and comfortable fitting to the wearer.

3. ) Reusability of the whole embodiment of the present invention or parts thereof such that the embodiment can be used for more than once for the intended purpose.;

For embodiments of the present invention to be reusable, there are a few requirements, namely deactivation of the trapped hazardous materials from the processed air so that they can no longer cause any harm to the user, removal of the trapped hazardous materials so that the embodiments of the present invention can be reused with no loss in functionalities fitting for their purposes.

To deactivate the hazardous materials, this can be achieved by a denaturation process, an oxidization process, a sterilization process, a neutralisation process or any combinations of such processes thereof. To remove the trapped hazardous materials so that the embodiments of the present invention can be reused with no loss in functionalities fitting for their purposes, this can be achieved by a washing process, an irradiation process, an oxidization process, a physical removal process, a chemical cleaning process or any combinations of such processes thereof.

4. ) Components of the various embodiments of the present invention is recyclable and does not harm the environment.

To be green to the environment, embodiments of the present invention should be constructed from recyclable materials and/or biodegradable materials. Furthermore, the reactive or bioactive elements of the embodiments of the present invention should be shielded from causing any harm to the user or the environment, and such elements can be transformed into harmless components within and outside of the embodiments.

A different approach to air purification

Most of air purification systems use a physical barrier as a means to filter out the airborne particles, microbes, nanoparticles, gaseous and toxins. The typical approach taken in these systems is to remove the dangerous hazardous materials from the air so that the air inhaled by the user is safe to breathe. This is not the ideal way to make the air inhaled by a user safe to breathe.

The present invention takes an innovative different approach –to make the air inhaled by the user safe to breathe by rendering all the hazardous materials in the air inhaled harmless to the human body. To achieve this goal, the present invention employs multiple components to render all the hazardous materials in the air inhaled through the use of the present invention, harmless to the human body.

One embodiment of the present invention takes the preventive measures of having the air inlets, and/or outlets, being away from possible directions of the pathways of hazardous materials in the air to be inhaled and/or exhaled by the human subject. Moreover, within another embodiment of the present invention, the pathways of the air travelled within said embodiment are arranged such that the hazardous materials in said air have the maximum possible chances to be in contacts with the different mechanisms or different apparatuses of said embodiment so that such inhaled air will be rendered harmless to the human being.

Negative air ion mechanisms

A negative air ion apparatus produces negatively charged ion particles in the air within an embodiment of the present invention so that such that these negative air ions can be used to remove particulate matters (both PM 10, PM 2.5 and PM 1.0) from the air. Negative air ions are single charged ions and will electrically charge such airborne particulate matters (PM) . Such charged PM particles will precipitate much faster than uncharged PM particles such that they attracted to nearby surfaces or to each other and settle faster under gravity. Such charged PM particles can also be collected with an opposite charged collector. Such PM particles can include, but not limited to airborne aerosols and/or droplets, viruses, and microbes such as of bacterial and fungal spores. Such negative air ion apparatus can be implemented in an enclosed or semi-enclosed chamber or channel wherein the air will travel within an embodiment of the present invention.

Ultra-violet (UV) radiation mechanisms

An UV radiation apparatus produces UV radiation (generally UV is electromagnetic radiation with wavelength from 10 nm to 400 nm, for embodiments of the present invention, near UV radiation with wavelength from 401 nm to 500 nm are also used) which is used to kill, deactivate or denature microbes and viruses in the air within an embodiment of the present invention such that the air is safe to be inhaled by the user. The UV radiation apparatus can also be used to generate negative air ions for the negative air ions mechanism. Such UV radiation apparatus can be implemented in an enclosed or semi-enclosed, shielded chamber or channel wherein the air will travel within an embodiment of the present invention. Such UV radiation apparatus can also be pulsed to ensure effectiveness of the sterilization process and yet maintaining the safety of the user. Possible UV radiation apparatus can be UV-A, UV-B, UV-C, far UV-C or a radiation source emitting one or more of these UV radiation spectrums.

A chemical oxidizer mechanism

A chemical oxidizer apparatus produces oxidizing agents that will bind with the hazardous materials airborne in the air within an embodiment of the present invention such that such oxidizing agents is used to kill, deactivate or denature microbes and viruses in the air within an embodiment of the present invention such that the air is safe to be inhaled by the user. Examples of such oxidizing agents are, but not limited to, hypochlorite (ClO) and hypochlorous acid (HOCl) . Moreover, there exists mechanisms to indicate to the user the effective lifetime of the chemical oxidizer apparatus via one or more indicators albeit chemically or physically induced changes in appearances or via information collated by attached sensors.

A physical nanometal oxide or nanometal mechanism

A physical nanometal oxide or nanometal apparatus can be a nanofilm of metal oxide or alloy oxide or nanometal that can kill, deactivate or denature microbes and viruses in the air that come in contact with such apparatuses within an embodiment of the present invention such that the air is safe to be inhaled by the user. Such nanofilm of metal oxide or alloy oxide or nanometal can comprise of TiO ₂ nanoparticles, Ag nanoparticles and Ag oxides, CuI nanoparticles, Cu and Cu oxides, CuO nanoparticles, Ni and Ni oxides, NiO nanoparticles, Zn and Zn oxides, Al and Al oxides, Pd and Pd oxides, Pt and Pt oxides, Fe and Fe oxides, Ru and Ru oxides, Co and Co oxides, Mn and Mn oxides, graphene and graphene derivatives, and different mixtures or composites or alloys of such metals and their metal oxides. Such a physical nanometal oxide or nanometal apparatus can be a nanofiber mesh or can be deposited on another physical material, such as polymers like polypropylene with either 20 or 25 grams per square meter (gsm) in density. Moreover, there exists mechanisms to indicate to the user the effective lifetime of the physical nanometal oxide or nanometal apparatus via one or more indicators albeit chemically or physically induced changes in appearances or via information collated by attached sensors.

Temperature raising mechanisms

A temperature raising apparatus is comprising of a mechanism to raise the temperature of the air that come in contact with this apparatus or within the vicinity of this apparatus to be at least 50 degrees Celsius, preferably at a temperate of about 70 degrees Celsius. Such elevated temperature will be sufficient to denature the protein of the microbial and thus serve to kill, deactivate or denature microbes and viruses in the air that come in contact with this apparatus or within the vicinity of this apparatus within an embodiment of the present invention such that the air is safe to be inhaled by the user. Examples of such a temperature raising apparatus can be comprising of an electrical heating source, a heat radiating source and/or an exothermic chemical source. Such a temperature raising mechanism can be incorporated into other apparatuses of the present invention.

Organic antimicrobial mechanisms

An organic antimicrobial mechanism comprises an apparatus wherein one or more organic antimicrobial agents such as aromatic oils, essential oils, spice extracts are embedded in a physical surface such that such an apparatus can kill, deactivate or denature microbes and viruses in the air that come in contact with the apparatus within an embodiment of the present invention such that the air is safe to be inhaled by the user. Examples of such organic antimicrobial agents can include, but not limited to fenugreek extracts, clove oil, chillies pepper oil, Peppermint essential oil -Mentha piperita, Tea Tree essential oil -Melaleuca alternifolia, Lavender essential oil -Lavandula angustifolia, Eucalyptus essential oil -Eucalyptus globulus, Oregano essential oil -Origanum heracleoticum, Palma Rosa essential oil -Cymbopogon martini, Orange essential oil -Citrus sinensis, Lemongrass essential oil -Cymbopogon citrullus, Geranium essential oil -Pelargonium graveolens, Citronella essential oil -Cymbopogon nardus, traditional Chinese medicine herbal extracts such as extracts from different herbs and herbal medicines, active carbons, and different mixtures thereof. Moreover, there exist mechanisms to indicate to the user the effective lifetime of the organic antimicrobial apparatus via one or more indicators albeit chemically or physically induced changes in appearances or via information collated by attached sensors. Organic-based detergents are also possible sources of such organic antimicrobial apparatuses.

A multi-layered air purification system

In one embodiment of the present invention there is provided a multi-layered air purification system (100) as illustrated in Figure 1. The multi-layered air purification system (100) is comprising different layers starting from the outer side (101) facing the outside air wherein potential hazardous materials are present in the ambient air.

A first layer (110) which is the most proximal to the outer side (101) is a hydrophobic/hydrophilic layer (111) such that the first layer (110) will repel moistures and water droplets from the outer side (101) from entering the multi-layered air purification system (100) . One embodiment of the first layer (110) can be a rigid or semi-rigid outer shell with a hydrophobic coating with good airflow (up to 100 L/min) . The outer shell of the multi-layered air purification system (100) can be molded to fit comfortably to the face of the wearer with non-air permeable hospital-grade memory form silicon lining seal. The outer shell can be constructed from polyester materials while the lining seal can be constructed from thermoplastic elastomer materials or cotton elastic materials.

A second layer (120) is where a negative air ion apparatus is housed such that negative air ions are generated to kill, deactivate or denature microbes and viruses in the air that is flowing through this housing. The negative air ions are also to remove the particulate matters (PM 1.0, PM 2.5 and PM 10) from the air flowing thru this housing. The negative air ions can be generated via conventionally known apparatuses of negative ions generation known in the art, including by not limited to UV radiation and corona discharges via charged electrode (121) .

A third layer (130) is where an UV radiation apparatus is housed such that UV radiation are generated to kill, deactivate or denature microbes and viruses in the air that is flowing thru this housing. The UV radiation in the third layer (130) can also be one of the sources of generating the negative air ions for the second layer (120) where the negative air ion apparatus is disposed. The UV radiation can be a periodic UV radiation apparatus (131) .

A fourth layer (140) is where a physical nanometal oxide apparatus is provided. Such a physical nanometal oxide apparatus can be an active oxide filtration layer that not just filters out particles (such as PM 1.0, PM 2.5 and PM 10) , but also actively kills, deactivates or denatures microbes and viruses in the air that is flowing through the fourth layer (140) . The fourth layer (140) can be constructed by a mesh comprising of the nanometal oxide alloy or a mixture thereof. The mesh will allow good air flow and may also have a furry surface embedded with cilia or nanofibers so that the contact surfaces with any hazardous materials in the air flowing therethrough is greatly increased. The fourth layer (140) can also be constructed by other materials including polymers such as polypropylene and the physical nanometal oxide apparatus is deposited thereon. The physical nanometal oxide apparatus can also be further photoactivated by the UV radiation from the third layer (130) . The fourth layer (140) can also have a temperature raising element. Possible candidates of such nanometal oxide include TiO ₂, Ag ₂O. Nanometal such as Ag can also be used.

A fifth layer (150) is where a chemical oxidizer apparatus is provided. Such a chemical oxidizer apparatus can be embedded onto a porous material that allows good air flow. The chemical oxidizing agent can be dispensed via a microfluidic apparatus (151) provided within the fifth layer (150) . The porous material that allows good air flow may also have a furry surface embedded with cilia or nanofibers so that the contact surfaces with any hazardous materials in the air flowing therethrough is greatly increased.

A sixth layer (160) is where an organic antimicrobial apparatus is provided. Such an organic antimicrobial apparatus can be embedded onto a porous material that allow good air flow. The organic antimicrobial agent can be dispensed via microfluidic apparatus (161) provided within this layer. Moreover, the organic microbial agent can also provide a refreshing aroma to the air flowing through this layer. This layer (160) can also be comprising a capillary layer (162) to draw out moisture away from the seventh layer (170) . The sixth layer (160) can also be constructed using materials such as, but not limited to nonwoven fabrics (e.g. CUPRO, LYOCELL, SONTARA, SAKURA, SEAWEED, and a mixture thereof) . The porous material that allows good air flow may also have a furry surface embedded with cilia or nanofibers so that the contact surfaces with any hazardous materials in the air flowing therethrough is greatly increased.

The seventh layer (170) is a separation layer that allows the moist air from the wearer's breath (102) to pass through rapidly to the sixth layer (160) . This ensure the wearer feels dry and comfortable. The seventh layer (170) can also be constructed using materials such as, but not limited to breathable fabrics (e.g. X-STATIC, SPANDEX, TENCEL, GORE-TEX, and a mixture thereof) .

The present embodiment of the present invention only exemplifies one possible variation of such a multi-layered air purification system (100) . For a person skilled in the art, different variations of the present embodiment are possible by either varying the positioning of respective layers or having more than one for one or more of the provided layers, or a variation of both the positioning and the number of layers used thereof.

The present embodiment of then present invention can also be implemented as a wearable air purification system, a face mask, a non-wearable purification system, a standalone air purification system and/or an integrated air purification system.

A multi-faceted air purification system

In another embodiment of the present invention there is provide a multi-faceted air purification system (200) as illustrated in Figure 2. The multi-faceted air purification system (200) is comprising two or more chambers starting from the outer side (201) facing the outside air wherein potential hazardous materials are present in the ambient air.

A first chamber (210) is where a hydrophobic/hydrophilic layer (211) is provided to repel moistures and water droplets from the outer side (201) from entering the multi-faceted air purification system (200) . One embodiment of the first chamber (210) can be a rigid or semi-rigid outer shell with a hydrophobic/hydrophilic coating with good airflow (up to 100 L/min) . The outer shell of the multi-faceted air purification system (200) fits comfortably to the face of the wearer with non-air permeable hospital-grade memory form silicon lining seal. The outer shell can be constructed from polyester materials while the lining seal can be constructed from thermoplastic elastomer materials or cotton elastic materials.

Within the first chamber (210) there is provided different apparatuses to kill, deactivate or denature microbes and viruses in the air that is flowing therethrough comprising a negative air ion apparatus (212) , a UV radiation apparatus (213) , and a physical nanometal oxide apparatus (214) . The negative air ions can be generated by conventionally known apparatus of negative ions generation in the art, including but not limited to UV radiation and corona discharges via a charged electrode (212a) . The physical nanometal oxide apparatus (214) can be constructed by a mesh comprising of the nanometal oxide alloy or a mixture thereof. The mesh can also be constructed by other materials including polymers such as polypropylene and the physical nanometal oxide apparatus is deposited thereon. The physical nanometal oxide apparatus can also be further photoactivated by the UV radiation apparatus (213) within the first chamber (210) . The mesh should also allow good air flow and may also have a furry surface embedded with cilia or nanofibers so that the contact surfaces with any hazardous materials in the air flowing therethrough is greatly increased. The first chamber (210) can also have a temperature raising apparatus to elevate the temperature of the air within the first chamber (210) .

A second chamber (220) is the chamber which is provided with at least a chemical oxidizer apparatus (221) , an organic antimicrobial apparatus (222) and a separation layer (223) that allows the moist air from the wearer's breath (202) to pass through rapidly to the first chamber (210) . This ensures that the wearer feels dry and comfortable. The separation layer (223) can also be constructed using materials including, but not limited to breathable fabrics (e.g. X-STATIC, SPANDEX, TENCEL, GORE-TEX, and a mixture thereof) . The chemical oxidizer apparatus (221) can be embodied by chemical oxidizer agents embedded onto a porous material (221a) that allow good air flow. These chemical oxidizing agents can be dispensed via a first microfluidic apparatus (221b) provided within the chemical oxidizer apparatus (221) . The organic antimicrobial apparatus (222) can be embodied by organic antimicrobial agents embedded onto a porous material (222a) that allow good air flow. These organic antimicrobial agents can be dispensed via a second microfluidic apparatus (222b) provided within the organic antimicrobial apparatus (222) . Moreover, the organic microbial agents can also provide a refreshing aroma to the air flowing through the organic antimicrobial apparatus (222) . The organic antimicrobial apparatus (222) can also be comprising a capillary layer (222c) to draw out moisture away from the breath of the wearer. The porous material (222a) can also be constructed using materials including, but not limited to, nonwoven fabrics (e.g. CUPRO, LYOCELL, SONTARA, SAKURA, SEAWEED, and a mixture thereof) . The porous material (222a) that allows good air flow may also have a furry surface embedded with cilia or nanofibers so that the contact surfaces with any hazardous materials in the air flowing therethrough is greatly increased.

The present embodiment of the present invention only exemplifies one possible variation of such a multi-faceted air purification system (200) . For a person skilled in the art, different variations of the present embodiment are possible by either varying the positioning of respective chambers or having more than one for one or more of the provided chambers, or a variation of both the positioning and the number of chambers used thereof.

An active air purification system

In yet another embodiment of the present invention there is provided an active air purification system (300) as illustrated in Figure 3. The active air purification system (300) has active apparatus (301) to circulate air through the purification system (302) within the active air purification system (300) . The purification system (302) can comprise of a multi-layered air purification system (100) or a multi-faceted air purification system (200) or a combination thereof. The active apparatus (301) can be an electrical-mechanical apparatus to circulate the air including, but not limited to, a fan, a pump and alike.

A passive air purification system

In a further embodiment of the present invention there is provided a passive air purification system (400) as illustrated in Figure 4. The passive air purification system (400) has passive apparatus (401) to circulate air thru the purification system (402) within the passive air purification system (400) . The purification system (402) can comprise of a multi-layered air purification system (100) or a multi-faceted air purification system (200) or a combination thereof. The passive apparatus (401) can be a mechanical apparatus to circulate the air including, but not limited to, one-way air valves, negative-positive air chambers, and alike.

Further embodiments of the present invention

In another embodiment of the present invention, the apparatuses to deactivate the inhaled airborne microbes are contained in canisters (A100) with spiraling inner structures as shown in Figure 5.

Each canister (A100) has air inlet openings (A101) that are slanted away from the orthogonal surface of the air inlet surface. The air inlet openings are provided so that airborne particles are not directly injected into the canister (A100) . Within the canister (A100) , there is provided a spiraling pathway for the airflow within the canister. The spiraling pathway are further compartmentalized into separate air chambers (A102) , wherein air from one chamber can flow into the next via non-line-of-sight air hole openings (A103) . These air hole openings (A103) again can be slanted away from the orthogonal surface of the air opening surface. Within each of these air chambers (A102) there could be a myriad of cilia-like structures (A104) or other mesh-like structures (A104) so that the present apparatuses to deactivate the airborne microbes can be embedded in such structures (A104) and such cilia-like structures (A104) increase the exposure surfaces for such deactivation apparatuses to be in contact with the airborne microbes in the flowing air flow. The air in the canister (A101) will flow in the spiraling pathway to exit via air outlet openings at the center of the spiraled pathway (A105) .

In yet another embodiment of the present invention, the canister (A100) of Figure 5 can be stacked with at least one other canister into a canister assembly as shown in Figure 6 as C1 and C2, respectively.

In each embodiment of canister assembly (C1, C2) , the external air will enter the stacked canisters (A100) at entry point B1, and such air will flow through the spiraled pathways (B2) in each canister as shown, and exiting the canister assembly at exit point B3. The motivation of stacking two or more of the canisters (A100) into canister assembly such as C1 and C2 or other stacking arrangements is to ensure the air flow volume capacity of each assembly is at least more than the volume of one lungful of inhaled air of a designated user of the air filtration apparatus. This will allow air flow retention in the canister (A100) or canister assembly (C1, C2) such that the airborne microbes in such air flow will be completely denatured by the deactivation apparatus embedded in said canister or canister assembly.

Embodiments with Ultra-violet (UV) radiation mechanisms

To test the effectiveness of different embodiments with UV radiation apparatuses of the present invention, the inventors have conducted the current tests:

Microbe tested: Escherichia coli (which are gram negative bacteria commonly found in the environment, foods and intestines of humans and animals)

UV Radiation apparatus tested: UV-C LED (Power: 1.5 W; Radiant Flux: 20 mW)

Procedure:

1. Equal volume/amount of E. coli culture were added on TiO ₂ coated and uncoated glass slides of similar size at 1cm x 1cm respectively.

2. The coated and uncoated glass slides were exposed to UV-C LED radiation for 3, 6, 12 and 24 seconds respectively. The distance between UV-C LED lamp and glass slides were set at 0.5 cm, 1 cm and 2 cm respectively.

3. Glass slides were submerged in 2 ml fresh culture media immediately post-UV-C irradiation.

4. The culture tubes were then incubated in 37-degree Celsius incubator overnight to allow the growth and recovery of bacteria that survived UV-C+TiO ₂ inactivation.

5. OD (optical density) reading at 600 nm (OD ₆₀₀) were measured on the next day to measure the density of each bacteria cultures post-UV-C test.

6. OD ₆₀₀ reading of 1 equal to ～8 x 10 ⁸ cells/ml

Figure 7 and Table 1 show the results of embodiments with UV-C radiation apparatus with and without TiO ₂ coating. The results, as recorded in Table 1, showed that TiO ₂ coating exhibited the most significant effectiveness in denaturing the bacteria when the culture was irradiated, from a distance of 1 cm, for 3 seconds, followed by radiation for a duration of 6 seconds, wherein under longer radiation durations, the UV-C radiation is equally effective for environment with and without TiO ₂ coatings.

Table 1: OD ₆₀₀ reading (relative microbial density “a.u. ” ) versus time of E. coli viability under UV-C radiation from a distance of 1 cm

Figures 8A-8B and Table 2 show the results of embodiments with UV-C radiation apparatuses with and without TiO ₂ coating. The results showed that TiO ₂ coating exhibited the most significant effectiveness in inactivating the bacteria when the culture was irradiated, for a duration of 6 seconds, from a distance of 0.5 cm for environment with TiO ₂ coatings.

Table 2: OD ₆₀₀ reading (relative microbial density “a.u. ” ) versus distance of where E. coli were cultured in terms of bacterial viability under UV-C radiation for a duration of 6 seconds

Results from Figure 7 and Figures 8A-8B suggest that the UV radiation apparatus (es) is/are best set at a distance of 1 cm or less, preferably at 0.5 cm, from the microbes to be denatured and anti-microbial coatings such as TiO ₂ can greatly increase the effectiveness of the microbial inactivation of the UV radiation apparatus (es) . Moreover, the UV radiation time should be at least 3 seconds, preferably at least 6 seconds.

Embodiments with Ultra-violet (UV) radiation apparatus and chemical apparatus

To test the effectiveness of different embodiments with UV radiation apparatus of the present invention with a chemical apparatus being a detergent –Triton X-100, the following tests are performed:

UV Radiation apparatus tested: UV-C LED (Power: 1.5 W; Radiant Flux: 20 mW)

Chemical apparatus tested: Detergent –Triton-X 100

Procedure:

1. Equal volume/amount (5 μL of OD600 = 2.0) of E. coli culture were added on TiO ₂ coated and uncoated glass slides of similar size at 1 cm x 1 cm respectively.

2. The E. coli culture was mixed with 2 μL of sterile water or 25% (v/v) Triton-X 100 solution.

3. For UV control and UV + detergent samples, samples were exposed to UV-C LED radiation for 1 second. The distance between UV-C LED lamp and glass slides was set at 1 cm.

4. For UV then detergent samples, Triton-X 100 solution was only mixed with E. coli culture after UV exposure.

5. Glass slides were submerged for 30 seconds in 2 mL fresh culture media immediately after UV-C exposure and detergent treatment.

6. The culture tubes were then incubated in a 37-degree Celsius incubator for 8 hours to allow the growth and recovery of bacteria that survived UV-C+TiO ₂+detergent inhibition.

7. OD (optical density) readings at 600 nm were measured after incubation to obtain the density of each bacteria culture post-UV-C test.

8. OD600 reading at 600 nm (OD ₆₀₀) reading of 1 equal to ～8 x 10 ⁸ cells/ml

The results, as recorded in Table 3, showed that although the addition of a chemical apparatus such as a detergent can improve the denaturing effectiveness of the UV radiation apparatus, the best results are to have the UV radiation apparatus to denature the microbial before other apparatus (es) of microbial inactivation, e.g., chemical apparatus in this example, is applied to the microbes. Thus, it is suggested that the UV radiation apparatus together with the physical nanometal oxide apparatus should be the first line of inactivation process to be done on the air breath into an embodiment of the present invention.

Table 3: OD ₆₀₀ reading (relative microbial density “a.u. ” ) versus time of E. coli survivability under UV-C radiation for 1 second with and without detergent from a distance of 1 cm

Some embodiments of the present invention

As the average breathing rate is about 12 breaths a minute and the average amount of air breath in on each breath is about 0.5 litres, thus, a normal adult human will breathe in about 6 litres of air per minute, so that translates to a breathing rate of about 100 ml of air per second. Hence, to ensure that the embodiments of the present invention can allow the UV radiation apparatus to denature the microbial in the breath-in air by 3 to 6 seconds, the capacity of the canisters in the embodiments of the present invention must be of a capacity of 300 ml to 600 ml in volume capacity.

Moreover, for effective denaturing of the microbial in the airflow within embodiments of the present invention, the chambers within the canisters of the embodiments of the present invention must be of a radius no greater than 0.5 cm. This allows the distance between the UC radiation apparatus to the chamber wall to be 1 cm or less.

INDUSTRIAL APPLICABILITY

The present invention relates to method and apparatuses for a multi-layered or multifaceted system for deactivating airborne particles. In particular, the present invention relates to method and apparatuses for a multi-layered or multifaceted system for deactivating airborne particles that is effective in deactivation and removal of airborne particles, microbes, nanoparticles, gaseous and toxins. One embodiment of the present invention is lightweight, compact and can be active or passive in operation, allowing effective and efficient operation for prolonged periods of time. Another embodiment of the present invention can be sterilized, cleaned and reused. Yet another embodiment of the present invention is environmentally friendly and non-toxic to human. It has potential to be developed into air filters, facial masks, surgical masks and respirator systems.

Claims

An assembly to inactivate microbes in air flowing therethrough comprising:

an indirect air flow pathway in said assembly, wherein the air flow in a direction from an air inlet opening of the assembly to flow out via an air outlet of the assembly, wherein said indirect air flow pathway comprises micro structures, micro cilia or meshes such that the air flowing through said assembly is in contact at least once on said micro structures, micro cilia or meshes while the air flow remains constant in terms of quantity and velocity thereof;

wherein in the indirect air flow pathway a plurality microbial deactivation apparatuses is disposed, comprising at least one UV radiation apparatus, at least one physical nanometal oxide or nanometal apparatus, at least one negative ion apparatus, at least one temperature raising apparatus, at least one chemical oxidizer apparatus and at least one organic antimicrobial apparatus, wherein the microbial deactivation apparatus closest to the air inlet opening of the assembly is the at least one UV radiation apparatus or the at least one negative ion apparatus, and wherein the at least one physical nanometal oxide or nanometal apparatus and the at least one UV radiation apparatus are disposed in the same section of the indirect air flow pathway in said assembly, and

wherein said assembly has an air volume capacity of at least 300 ml.
The assembly according to claim 1, wherein the at least one UV radiation apparatus is a UV-C radiation LED source.
The assembly according to claim 1, wherein the at least one physical nanometal oxide or nanometal apparatus is at least one micro structure, micro cilia or mesh coated with at least one nanofilm of TiO ₂.
The assembly according to claim 1, wherein the at least one negative ion apparatus is also a UV radiation apparatus.
The assembly according to claim 1, wherein the at least one organic antimicrobial apparatus is a detergent.
An active or a passive air purification system comprising the assembly according to any one of claims 1 to 5.
An air purification system comprising the assembly according to any one of claims 1 to 5 being configured into either a multifaceted or multi-layered structure, or a combination thereof.
A breathing apparatus to inactivate microbes in air flowing therethrough comprising:

an indirect air flow pathway in said breathing apparatus wherein the air flow in a direction from an air inlet opening of the breathing apparatus to flow out via an air outlet of the breathing apparatus, wherein said indirect air flow pathway comprises micro structures, micro cilia or meshes such that the air flowing through said breathing apparatus is in contact at least once on said micro structures, micro cilia or meshes while the air flow remains constant in terms of quantity and velocity thereof;

wherein in the indirect air flow pathway a plurality of microbial deactivation apparatuses is disposed, comprising at least one UV radiation apparatus, at least one physical nanometal oxide or nanometal apparatus, at least one negative ion apparatus, at least one temperature raising apparatus, at least one chemical oxidizer apparatus and at least one organic antimicrobial apparatus, wherein the microbial deactivation apparatus closest to the air inlet opening of the breathing apparatus is the at least one UV radiation apparatus or the at least one negative ion apparatus, and wherein the at least one physical nanometal oxide or nanometal apparatus and the at least one UV radiation apparatus are arranged in the same section of the indirect air flow pathway in said breathing apparatus, and

wherein said breathing apparatus has an air volume capacity of at least 300 ml.
The breathing apparatus according to claim 8, wherein the at least one UV radiation apparatus is a UV-C radiation LED source.
The breathing apparatus according to claim 8, wherein the at least one physical nanometal oxide or nanometal apparatus is at least one micro structure, micro cilia or mesh coated with at least one nanofilm of TiO ₂.
The breathing apparatus according to claim 8, wherein the at least one negative ion apparatus is a UV radiation apparatus.
The breathing apparatus according to claim 8 wherein the at least one organic antimicrobial apparatus is a detergent.
An active or a passive air purification system comprising the breathing apparatus according to any one of claims 8 to 12.
An air purification system comprising the breathing apparatus according to any one of claims 8 to 12 being configured into a multifaceted or multi-layered structure, or a combination thereof.
An attachment to a breathing apparatus which inactivates microbes in the air flowing therethrough comprising:

an indirect air flow pathway in said attachment wherein the air flow in a direction from an air inlet opening of the breathing apparatus to flow out via an air outlet of the breathing apparatus, wherein said indirect air flow pathway comprises micro structures, micro cilia or meshes such that the air flowing through said attachment is in contact at least once on said micro structures, micro cilia or meshes while the air flow remains constant in terms of quantity and velocity thereof, and

wherein in the indirect air flow pathway, a plurality of microbial deactivation apparatuses is disposed, comprising at least one UV radiation apparatus, at least one physical nanometal oxide or nanometal apparatus, at least one negative ion apparatus, at least one temperature raising apparatus, at least one chemical oxidizer apparatus and at least one organic antimicrobial apparatus, wherein the microbial deactivation apparatus closest to the air inlet opening of the breathing apparatus is the at least one UV radiation apparatus or the at least one negative ion apparatus, and wherein the at least one physical nanometal oxide or nanometal apparatus and the at least one UV radiation apparatus are disposed in the same section of the indirect air flow pathway in said attachment, and

wherein said attachment has an air volume capacity of at least 300 ml.
A breathable device comprising one or more of the assemblies according to any one of claims 1 to 5 and at least one of an active and a passive air flow and purification assemblies for wearer of said breathable device to inhale and exhale air without air flow blockage while hazardous small particles including airborne particles, microbes, nanoparticles, gaseous and toxins from inhaled air are deactivated and removed by physical and chemical inactivation mechanisms provided by said one or more breathing apparatuses prior to reaching a respiratory system of the wearer.
A respirator comprising one or more of the assemblies according to any one of claims 1 to 5 being arranged to maximize exposure surface area thereof to one or more compartments of the respirator where air flows from at least an air inlet to at least an outlet of the respirator through the one or more compartments such that deactivation and removal of hazardous small particles including airborne particles, microbes, nanoparticles, gaseous and toxins in air from the air inlet by physical and chemical inactivation mechanisms of the breathing apparatuses is maximized while quantity and velocity of the air flowing through the respirator remain constant.