U.S. patent application number 12/082983 was filed with the patent office on 2008-10-30 for electrostatically charged filter media incorporating an active agent.
This patent application is currently assigned to Triosyn Holding Inc.. Invention is credited to Pierre Jean Messier.
Application Number | 20080264554 12/082983 |
Document ID | / |
Family ID | 31999234 |
Filed Date | 2008-10-30 |
United States Patent
Application |
20080264554 |
Kind Code |
A1 |
Messier; Pierre Jean |
October 30, 2008 |
Electrostatically charged filter media incorporating an active
agent
Abstract
There is provided a protective media and a method of
manufacturing the same. In one aspect, the protective media
includes a porous dielectric carrier, an active agent incorporated
in the porous dielectric carrier, and an electrostatic charge
across at least a portion of the porous dielectric carrier. This
innovative media is capable of eradicating microorganisms and/or
toxins more efficiently than prior art solutions and can also
self-sterilize.
Inventors: |
Messier; Pierre Jean;
(Mirabel, CA) |
Correspondence
Address: |
GOODWIN PROCTER L.L.P;ATTN: PATENT ADMINISTRATOR
620 Eighth Avenue
NEW YORK
NY
10018
US
|
Assignee: |
Triosyn Holding Inc.
Quebec
CA
|
Family ID: |
31999234 |
Appl. No.: |
12/082983 |
Filed: |
July 3, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10528005 |
Jun 9, 2006 |
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PCT/IB03/04553 |
Sep 8, 2003 |
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12082983 |
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60411006 |
Sep 16, 2002 |
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60434526 |
Dec 19, 2002 |
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60458800 |
Mar 28, 2003 |
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Current U.S.
Class: |
156/244.11 ;
264/121 |
Current CPC
Class: |
A62B 23/025 20130101;
D06M 11/76 20130101; B03C 3/60 20130101; Y10T 442/60 20150401; B01D
39/2017 20130101; B01D 2239/0407 20130101; B01D 2239/0442 20130101;
B01D 2239/0492 20130101; D06M 10/025 20130101; D06M 13/355
20130101; D06M 11/83 20130101; B01D 39/2031 20130101; D01D 5/0985
20130101; A61L 9/16 20130101; Y10T 442/696 20150401; D06M 11/38
20130101; Y10T 442/699 20150401; D06M 16/00 20130101; D06M 11/155
20130101; B01D 39/2072 20130101; A41D 13/1192 20130101; B01D 39/18
20130101; Y10T 428/249953 20150401; B01D 2239/0435 20130101; B01D
39/1623 20130101; B03C 3/28 20130101 |
Class at
Publication: |
156/244.11 ;
264/121 |
International
Class: |
B32B 38/00 20060101
B32B038/00; B32B 38/08 20060101 B32B038/08; B29C 47/02 20060101
B29C047/02 |
Claims
1. A method of making a non-woven material, including: i. providing
an extruder having an outlet; ii. providing a collecting web below
the outlet of said extruder; iii. providing a hot melt of
extrudable material; iv. extruding said extrudable material with
said extruder to provide a flow of cooling extruded fibers to fall
toward said collecting web; and v. providing a cloud of an active
agent at a location adjacent said outlet of said extruder so that
said cloud envelops the cooling fibers while said fibers are still
in a quasi-liquid quasi-solid state so that said active agent
settles and collects and is intermeshed or entrapped with said
fibers on the collecting web forming a media, wherein said active
agent is a halogenated resin.
2. The method of making a non-woven material as defined in claim 1
further including forming said media into a mesh.
3. The method of making a non-woven material as defined in claim 1
in which said cloud is in a physical state selected from the group
consisting of a vapor, a fine dry dust, an atomized particulate and
an aerosolized particulate.
4. The method of making a non-woven material as defined in claim 2
further including the step of applying an electric charge across
said mesh.
5. A method of making a non-woven material, including: i. providing
an extruder having an outlet; ii. providing a collecting web below
the outlet of said extruder; iii. providing a reservoir of
extrudable material; iv. extruding said extrudable material with
said extruder to provide a flow of extruded fibers to fall toward
said collecting web; and v. providing a cloud of an active agent at
a location adjacent said flow of extruded fibers so that said cloud
envelops the fibers while said fibers are falling so that said
active agent settles and collects and is intermeshed or entrapped
with said fibers on the collecting web forming a media, wherein
said active agent is a halogenated resin.
6. The method of making a non-woven material as defined in claim 5
further including forming said media into a mesh.
7. The method of making a non-woven material as defined in claim 5
in which said cloud is in a physical state selected from the group
consisting of a vapor, a fine dry dust, an atomized particulate and
an aerosolized particulate.
8. The method of making a non-woven material as defined in claim 6
further including the step of applying an electric charge across
said mesh.
9. A method of making an antimicrobial filter comprising: i. mixing
an iodinated resin with a polymer; ii. extruding the iodinated
resin and polymer mixture to form a plurality of extruded fibers
such that the iodinated resin is incorporated into the fibers; iii.
collecting the fibers on a collecting web to form a nonwoven
web.
10. The method of claim 9 wherein said iodinated resin is in dust
form prior to extrusion.
11. The method of claim 9 further comprising applying an electric
charge across the nonwoven web.
12. The method of claim 9 further comprising pressuring and heating
the fibers to form a felt.
13. The method of claim 9 wherein the polymer is selected from the
group consisting of polypropylene, nylon and polyethylene.
14. The method of claim 9 wherein the polymer and iodinated resin
are emulsified at elevated temperature and pressure to form a melt
prior to forming the fibers.
15. The method of claim 9 wherein the nonwoven is formed using a
melt blown process.
16. The method of claim 9 wherein the nonwoven is formed using a
spun blown process.
17. The method of claim 15 wherein the extruded fibers are
attenuated and then quenched.
18. A method of making an antimicrobial filter comprising: i.
extruding a polymer to form a plurality of extruded fibers; ii.
spraying an active substance on the extruded particles, wherein the
active substance is an iodinated resin; iii. bonding the fibers
containing the active agent into a nonwoven web.
19. The method of claim 18 wherein the iodinated resin is sprayed
in the form of an aerosol.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser.
No. 10/528,005, filed on Mar. 16, 2005, which is a 371 of
PCT/IB03/04553, filed on Sep. 8, 2003, which claims the benefit of
priority to U.S. Provisional Application Nos. 60/411,006,
60/434,526 and 60/458,800, filed on Sep. 16, 2002, Dec. 19, 2002
and Mar. 28, 2003, respectively, the contents of each are hereby
incorporated by reference herein in the entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to electrostatically charged
filter media and more particularly to an electrostatically charged
media with an active agent incorporated thereon, and a method of
making the same.
BACKGROUND OF THE INVENTION
[0003] Prior art filter methods include, for example, mechanical
filtration--a physical retention of particles larger than the pores
of the filter media; electrostatic filtration--adhering particles
to fibers in the filter without killing/deactivating the particles;
and filtration as taught and claimed in U.S. Pat. No. 5,980,827
which issued to the inventor hereof on Nov. 9, 1999 and is entitled
"Disinfection Of Air Using An Iodine/Resin Disinfectant." It has
been determined that improved iodinated resin filtration occurs in
a thin media when the product is incorporated to a media with a
convoluted pathway. By forcing the microorganism/toxin to pass
through a circuitous route, the microorganism/toxin is eventually
killed/deactivated. One method for providing a circuitous route is
to employ a nonwoven media.
[0004] In published U.S. patent application number 20010045398
entitled "Process For The Immobilisation Of Particles In A Three
Dimensional Matrix Structure" the non-woven material is first
produced and then an iodinated resin, such as the one disclosed in
U.S. Pat. No. 5,639,452 (the '452 patent) is added using alcohol or
a partial solvent with a high pulsation vacuum pump that opens the
filter pores so that the active agent will go through it (the
"Triosyn" resin). The contents of the '452 patent is incorporated
by reference in its entirety herein.
[0005] U.S. Pat. No. 6,346,125 teaches incorporating an aqueous
antimicrobial agent into a non-electrostatically charged non-woven
material. Specifically, the '125 patent describes a particular
process for incorporating an aqueous antimicrobial agent into a
non-electrostatically charged non-woven. However, without the
electrostatic properties, the non-woven must be of greater
thickness so that the microorganism has sufficient contact time
with the antimicrobial agent for decontamination.
[0006] U.S. Pat. No. 5,952,092 teaches a non-woven fabric with
chemically active particles. However, this patent does not teach
using an electrostatic substrate as in the present innovation.
[0007] Nonwoven electrets and methods of manufacturing the same are
known in the art. For example, U.S. Pat. No. 5,409,766 describes a
nonwoven fabric in an electret state composed of monofilaments
formed of a polymer composition capable of dust collection over a
prolonged time and in a hot and humid condition. Also disclosed are
processes for producing this nonwoven fabric, as well as a
filtering air masking material composed of that nonwoven fabric.
However, this prior art system does not provide
antimicrobial/antitoxin properties. Thus, the microorganism/toxin,
while suspended within the nonwoven fabric, is not sterilized or
deactivated. Once the electrostatic properties of the nonwoven are
depleted or the material is saturated, the microorganism/toxin may
be released back into the atmosphere.
[0008] Electrostatically charged filters are known to be used in
facemasks, for example. With respect to both, one of the problems
of face seal is well known and represents a limitation that the
industry has been trying to address. The problem resides in the
fact that from one morphological physical structure of a human
being or structure to the next the differences generate such a wide
spectrum of geometrical deviations that it has been difficult to
create a 100% airtight seal. For a facemask the difficulty in
creating a seal occurs between the skin and the mask for a range of
face sizes and shapes. Various different technological means have
been tried, for example using, adhesive seals, flat and wide seals
and resilient material seals. The industry has oriented its work on
creating an airtight seal, however, the pressure differential
generated actually forces air in the gaps between seal and skin
thus bypassing the air filter material. The electrostatic filter of
the present invention may be made of a spongy or other breathable
nonwoven material so as to minimize the pressure differential, thus
preventing air from being forced through the gaps. Further, it
effectively makes the gasket used to create a closure between the
user and the facemask out of a thin filter having a low-pressure
drop like the electrostatic filter and having the added benefit of
the active agent incorporated thereon.
[0009] Other known prior art that teach the use of high pressure
drop media includes the mechanical filtration of the HEPA filter.
However, the pressure drop of the present invention is
approximately 50% to 90% lower than that of the HEPA filter alone.
The filter further includes a material that kills on passage
vegetative bacteria, spores, and viruses. They are filtered out of
the airstream and are killed. In addition, the present invention is
self-sterilizing, meaning that not only does it filter air passed
there through, it kills the bacteria trapped on the filter.
Therefore, the media protects both the user and the outside
air.
[0010] Given the shortcomings of the prior art, it is advantageous
to have an electret, which has improved characteristics over known
solutions. The present innovation comprises a substrate that
supports an active agent and is a dielectric.
SUMMARY OF THE INVENTION
[0011] The present invention overcomes the aforementioned problems
of the prior art. Specifically and in accordance with one aspect of
the present invention, there is provided herein an
electrostatically charged non-woven media that has active agents
incorporated therein. This innovative media is capable of
eradicating microorganisms and/or toxins more efficiently than
prior art solutions and can also self-sterilize.
[0012] The present invention additionally provides for methods of
making the electrostatically charged filter media having an active
agent incorporated therein. The substrate may be manufactured
according to various methods; the active agent may be incorporated
according to various methods; and the electrostatic charge may be
provided according to various methods, all of which are described
herein or are known in the art.
[0013] Because substantially less active agent is used for each
filter costs are reduced while maintaining effectiveness.
Additionally, the enhanced electrostatic filter of the present
invention provides added performance of the active agent and
electrostatic properties.
[0014] In addition to the above aspects of the present invention,
additional aspects, features and advantages will become better
understood with regard to the following description in connection
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 depicts aspects of an exemplary embodiment of the
present invention in accordance with the teachings presented
herein.
[0016] FIGS. 2 and 3 depict exemplary embodiments of
electrostatically charged substrates.
[0017] FIG. 4 depicts an exemplary embodiment for providing a
nonwoven media with an active agent incorporated thereon.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The following sections describe exemplary embodiments of the
present invention. It should be apparent to those skilled in the
art that the described embodiments of the present invention
provided herein are illustrative only and not limiting, having been
presented by way of example only. All features disclosed in this
description may be replaced by alternative features serving the
same or similar purpose, unless expressly stated otherwise.
Therefore, numerous other embodiments of the modifications thereof
are contemplated as falling within the scope of the present
invention as defined herein and equivalents thereto.
[0019] The present invention provides an electrostatically charged
filter media comprising a substrate with an active agent
incorporated therein.
[0020] Filter Media
[0021] The filter media of the present invention includes (1) a
substrate, (2) an active agent incorporated therein and (3) an
electrostatic charge.
[0022] Substrate
[0023] The substrate comprises any material having dielectric
properties or capable of being enhanced to have dielectric
properties and which is capable of having an active agent
incorporated therein.
[0024] In a particular embodiment, the substrate may be a fiber
based material having a fibrous matrix structure; it may be a
sponge like material have an open cell matrix structure; it may be
flexible or inflexible; etc.
[0025] As stated above, in one embodiment, the substrate is a
nonwoven fabric. Nonwoven is a type of fabric that is bonded
together rather than being spun and woven into a cloth. It may be a
manufactured sheet, mat, web or batt of directionally or randomly
oriented fibers bonded by friction or adhesion; it may take the
form of a type of fabric. FIG. 1 is provided as an exemplary
embodiment of a nonwoven fabric.
[0026] In another embodiment, the substrate may be a nonwoven
textile of varying fluffiness, comprising polymer fiber. The
polymer may be for example, nylon, polyethylene, polypropylene,
polyester, etc. or any other polymer suitable for a filter
substrate. Additionally, the substrate can be made of materials
other than polymer fiber.
[0027] The nonwoven material may be of a type suitable for a high
efficiency particulate air filter (i.e. a HEPA filter). A suitable
nonwoven material may be obtained from Technol Aix en Provence
Cedex 03 France (see Canadian patent no. 1,243,801); another
suitable material may also be obtained from Minnesota Mining &
Manufacturing Co. (3M). The nonwoven material has a three
dimensional structure which should be configured in such a fashion
as to provide a matrix capable to entrap (i.e. physically) the
desired active agent. For example if the nonwoven material is based
on fibers, the structural fibers of the nonwoven material may be
present and distributed in such a fashion as to provide a fibrous
matrix structure able to entrap the desired active agent. The
nonwoven material may have a microstructure. In a particular
embodiment, the active agent has a size appropriate to be entrapped
by the three dimensional (e.g. web) matrix structure of the desired
nonwoven material.
[0028] Alternative substrates may further include glass fibers and
fibers, such as cellulose, that are ultimately formed into a
paper-based filter media. Any substrate capable of acting as
carrier for the active agent and having dielectric properties or
capable of having dielectric properties imparted to it, would be a
suitable substrate for the present invention. When substrates that
do not have strong dielectric properties are used, such as glass
fibers, additives may be provided to improve the dielectric
properties of the substrate. The present invention is not limited
to a nonwoven material. Other suitable substrates may include
spongy materials or foam.
[0029] Active Agent
[0030] The active agent of the present invention may be, for
example, an antimicrobial, an antitoxin, or the like. The
antimicrobial may be biostatic and/or biocidal. Biostatic is a
material that inhibits the growth of all or some of bacteria
spores, viruses, fungi, etc. (having bioactive particles), and a
biocidal is a material that kills all or some of bacteria spores,
viruses, fungi, etc. Preferably, the biocidal comprises the
iodinated resin particles, such as those described above in the
'452 patent, as described above. Other suitable active agents
include silver, copper, zeolyte with an antimicrobial attached
thereto, halogenated resins, and agents capable of
devitalizing/deactivating microorganisms/toxins that are known in
the art, including for example activated carbon, other metals and
other chemical compounds. For example, a non-exhaustive list of
suitable metals and/or chemical compounds is as follows:
[0031] Exemplary Metals
[0032] Aluminum
[0033] Barium
[0034] Boron
[0035] Calcium
[0036] Chromium
[0037] Copper
[0038] Iron
[0039] Magnesium
[0040] Manganese
[0041] Molybdenum
[0042] Nickel
[0043] Lead
[0044] Potassium
[0045] Silicon
[0046] Sodium
[0047] Strontium
[0048] Zinc
[0049] Exemplary Chemical Compounds
[0050] N-methyl piperazine
[0051] Potassium Hydroxide
[0052] Zinc Chloride
[0053] Calcium chloride
[0054] Mixture of Sodium carbonate and sodium bicarbonate
[0055] Reference in the specification to antimicrobial is used for
ease of reading and is not meant to be limiting.
[0056] Electrostatic Charge
[0057] The filter media with an active agent incorporated thereon
is also electrostatically charged. Accordingly, there is a
potential across the surface(s) of the media creating a field
wherein the field can attract and/or repel charged particles
introduced to the media so that in some instances it alters the
path of travel of the charged particles.
[0058] FIGS. 2-3 provide exemplary representations of
electrostatically charged media. Electrostatically charged filter
media of the present invention may, for example, be single or
multi-layered. Each layer may be individually charged. A single
layered media can have a positive charge on one side and a negative
charge on the other. An example of a multi-layered media is a
double-layered media. Preferably, a double layered media is used
wherein the double-layered media comprises two layers, each being
positively charged on one side and negatively charge on the other
side, wherein the two layers are separated by an airspace and the
two layers are oriented so that the negative side of one of the two
layers is closest to the positive side of the other layer. In this
two-layer embodiment, the air space increases the net dielectric
constant of the electrostatically charged filter media.
[0059] Preferably, a high dielectric constant is provided to
maintain the charge for an extended period of time. For example,
air provides a good dielectric constant, as can be employed in an
airspace as described above. Thus, the present invention may be
effective even when wet or in a humid environment.
[0060] The resulting media is an insulating carrier with an active
agent adhered thereto or impregnated therein and having an
electrostatic charge. The media according to the present invention
can be produced of different thickness, density and pressure drop.
The media described herein can be used in, for example: clothing,
wound dressings, air filters, shelters, liners and generally, any
filter material.
[0061] Method of Manufacturing
[0062] The present invention additionally provides for a method of
manufacturing the electrostatically charged filter media having an
active agent incorporated thereon. The substrate itself may be
manufactured according to various known methods, such as melt
blown, spun blown, air laid, carted, etc.
[0063] Method of Incorporating the Active Agent
[0064] Prior art incorporation methods using polypropylene require
the use of polyethylene to maintain a tackiness to the fibers to
hold the solid particulate for a longer amount of time to prevent
the particulate from falling off the fibers. In the present
invention, the active agent, such as the iodinated resin disclosed
in the '452 patent, may be physically entrapped in the fibers.
Thus, the active agent does not have to adhere to the fibers to be
incorporated into the media.
[0065] In the present invention, the active agent may be
incorporated to the substrate according to various methods. For
example, liquid emulsification of the active agent in the melt at
increased temperature and increased pressure for mix and melt
processes, or incorporation by spraying the active agent after
extrusion of non-woven fibers during processing.
[0066] In a preferred embodiment, as shown in FIG. 4, polymer
granules, such as polypropylene granules, are extruded through an
extruder; the extruded fibers being of varying thickness and
length. As the fibers are extruded they fall toward a collecting
web. A desired active agent is provided in a cloud at a location
closest to the extrusion point of the resulting fibers. The cloud
envelops the cooling fibers while the fibers are still in a
quasi-liquid quasi-solid state. In one embodiment, the active agent
particulate may range from 0.2 microns to 0.5 millimeters. However,
one of ordinary skill in the art can apply active agents with
smaller and bigger particulates size. The active agent particulate
settles and collects so that it is intermeshed or entrapped with
the fibers on the collecting web. After the fibers with the active
agent incorporated thereon falls to the collecting web, the
resulting media is formed into a mesh by known methods.
Additionally, the cloud may be in various physical states including
a vapor, fine dry dust, or atomized or aerosolized particulate.
Advantageously, cloud incorporation may occur at room temperature
with particulate also at room temperature. Further, the thickness,
length and pressure define the mechanical properties of the
resulting media.
[0067] A suitable melt blown system for the above embodiment is the
Accuweb provided by Accurate Products Co. of Hillside, N.J.
[0068] Various other methods of incorporating an active agent to a
filter media are suitable for the present invention. First, for
example, using the method disclosed in published U.S patent
application number 20010045398 A1. Second, soaking a bail of
hair-like extruded fibers in an active agent (and using alcohol to
achieve the soak) and then creating the felt using pressure and
temperature. Third, taking solid polymer granules manufactured with
an active agent mixed in an extruder hopper to create a mixture
that is then extruded into fine hair-like bails. Felt is then
formed through a temperature and pressure process. Fourth,
extruding a substrate, such as a polymer in to a hair-like
substance on to which an active agent is sprayed in solid after the
extrusion. The active agent may be vaporized like an aerosol.
Fifth, the active agent can be injected or sprayed into non-woven
fabric as the fabric is being pressurized. Sixth, carting bails of
filament and mixing the resulting media with the active agent to
generate a sheet having the active agent incorporated therein.
Seventh, depositing the active agent on a non-woven media and
thereafter needle-punching the media to impregnate the active agent
through and through the media. Other methods may be used.
[0069] In another embodiment of the present invention, polymer
granules are placed in a hopper of an extruder with active agent in
dust form prior to extrusion. Thus, the active agent is mixed in
the hopper prior to the melt. The two components are mixed, heated
and then extruded to form a thin "hair" fiber used to make a felt.
The resulting hair in the above embodiments having the active agent
incorporated thereto is a bail-like wool. The substrate could be
transparent depending on the polymer used. Additionally, a
resulting polymer fiber having the active agent incorporated
thereto can be treated with water, pressurized and then heated to
form a felt. In other embodiments, the resulting polymer fiber
having the active agent incorporated thereto can an be air laid,
vacuum laid, water laid, etc.
[0070] Although not specifically described herein, other
conventional or known methods that achieve incorporation of an
active agent to a substrate are suitable for the present invention.
Thus, at this point the substrate has an active agent incorporated
therein.
[0071] Method of Electrostatically Charging
[0072] The substrate having an active agent incorporated therein is
provided with an electrostatic charge. The charge may be induced by
using a corona, needle punching, chemical enhancement, any other
known charge inducing system or method, or a combination of any of
the foregoing. Needle punching creates high-level friction thus
adding a charge.
[0073] In a particular embodiment, to make the electrostatically
charged non-woven fabric the formed media, such as felt, is placed
into a corona system of about 25 Kv, slow pass, until fully
charged. The resulting material holds its charge for between about
6 months to 2 years.
[0074] Operation of an Electrostatic Filter Media
[0075] In operation, a contaminated air or fluid stream is
introduced to a filter employing the electrostatically charged
filter media of the present invention. The air/fluid stream may be
forced or drawn through the filter media by means of a pressure
gradient. The stream may contain contaminant particles of various
sizes to be removed or treated by the filter element. As the stream
approaches the filter media, it is directed through the filter
media such that the contaminate particles are brought into contact
with the filter media and removed from the stream or treated by the
active agent as describe elsewhere in this application. This is
achieved through the properties of the filter, which causes the
particles to follow a convoluted pathway through the filter
element, thus increasing the time that the contaminant is in
contact with the active agent. This increased contact time
increases the effectiveness of the active agent in treating the
particles in the stream.
[0076] The convoluted path that the particles follow is the result
of the added electrostatic properties and the nonwoven properties
of the substrate of the filter element. With respect to the
electrostatic properties of the filter element, the convoluted
pathway of the contaminant particles may be attributed to the
particles polar nature. Polar molecules are neutrally charged and
are also large in size. Because of the large size, the contaminants
have a magnetic moment, which when subjected to an electric field
causes the contaminant particle to be diverted from its
pathway.
[0077] Additionally, the convoluted path of the contaminant
particles is attributable to the nonwoven properties of the filter
substrate. This is achieved because the nonwoven substrate had no
direct and continuous pathway for the stream to pass through.
Instead, due to the nonwoven properties, the substrate is made up
of a porous material wherein no single pores of the material forms
a continuous pathway through the substrate. Therefore, the stream
and the particles carried by the stream are continuously diverted
through the substrate.
[0078] Accordingly, the travel time through the filter is
lengthened and the exposure to the active agent is increased.
[0079] Additional Uses
[0080] The present invention can also be used in a manner
consistent with existing nonwoven fabrics. Uses in various goods
include both durable and disposable goods. For example, nonwovens
can be used products such as diapers, feminine hygiene, adult
incontinence, wipes, bed linings, automotive products, face masks,
air filtration, water filtration, biological fluids filtration,
home furnishings and geotextiles. The media described herein can
also be used in, for example: clothing, wound dressing, air filter,
shelters, and liners. Additional uses include those known in the
art for electrostatic filters and antimicrobial or antitoxin
filters.
[0081] In a particular embodiment, the filter media according to
the present invention with or without the active agent can be used
as a closure or to make a filter closure for air filters for
products such as facemasks and HVAC. According to the present
invention there is provided a closure material made of substrate
having electrostatic properties and an electrostatic material with
an active agent incorporated therein, where the material is a high
loft (in one embodiment, approximately, 1'' thick) breathable
material of a tri-dimensional structure and is placed around the
mask or air filter in order to not create a so-called airtight
junction but instead creates a breathable closure that actually
covers all the contours of the different geometrical surface to
provided a permeable closure, having filtering properties. This
approach makes the closure into a filter whereby air that bypasses
the mask through gaps caused by a non-perfect fit, still passes
through the closure and is filtered. In addition, contrary to a
"resilient" closure the pressure differential that is detrimental
in an airtight approach is reversed in our approach since the air
following the path of least resistance will pass through the filter
material of the mask instead. This method of closing a facemask or
other filter type could also be achieved with a substitution of the
non-woven filter element with a breathable foam having the same
properties. Thus, while prior art facemask attempt to block air
flow at the closure, the facemasks of the present invention acts as
a gasket that allows air there through and kills the spores, virus,
bacteria, fungi, etc. traveling through the airstream with an
effective active agent, such as the iodinated resin disclosed in
the '452 patent, described above. Additionally, the use of straps
to hold the mask in place compresses the gasket of the present
invention to fit essentially all faces.
[0082] Experimental Data
[0083] Experimental tests were performed comparing a particular
embodiment of the filter media of the present invention to an
existing electrostatic filter. Each test was run in the same
environment to treat air with a different contaminant. The
experimental data provided was collected during these tests. In
each of the tests a contaminant was introduced into a chamber in a
controlled amount and fed into four lines. Two of the lines
included a filter according to the present invention comprising an
electrostatically charged filter with an iodinated resin according
the '452 patent incorporated thereto. The third line included an
electrostatically charged filter, known as Transweb. This filter
does not have antimicrobial properties or any other type of active
agent incorporated thereto. And a fourth line was provided as a
control, having no filter and was used to confirm that the amount
of contaminant entering the control chamber was equivalent to the
amount of contaminant exiting the control chamber.
[0084] Exhibit A sets forth experimental data illustrating certain
features of exemplary embodiments of the present invention.
Experiment No. AF276, describes the performance of different
filtration membranes against BG spores for 30, 60, 120, 180, 240,
300, and 360 minutes of filtration. BG spores must be present in
amounts of about 8,000 to 30,000 spores to cause illness in the
average human. As can be seen in Exhibit A, for each of the 30, 60,
120, 180, 240, 300 and 360-minute tests, the filter of the present
invention achieved a 100% reduction of BG spores from the
airstream.
[0085] As can be seen in Exhibit A, the electrostatic filter of the
present invention achieves the essentially the same or similar net
effect as the Transweb in these tests. However, an important
advantage provided is that the present invention sterilizes the
spores rather than just holding the spores to the filter. Thus,
unlike the present invention, if the Transweb is handled by a user
or is contacted by the skin, contamination will occur. The present
invention maintains the hygiene of the filter.
[0086] Turning now to Exhibit B, the results of Experiment AF270
there is shown test results for the performance of different
filtration membranes against MS2 viruses for 30, 60, 120, 180, 240
300, and 360 minutes of filtration. Virus amounts ranging from 1 to
1000 viruses will cause illness in the average human. Thus, the
presence of even one virus can cause illness in a human. As can be
seen in Exhibit B, for each of the 30, 60, 120, 180, 240, 300 and
360-minute tests, the filter of the present invention achieved a
100% reduction of MS2 viruses from the airstream. However, the
Transweb does not achieve a 100% reduction in MS2 viruses and
allows between 1000 to 10000 viral units to be found in the
effluent air stream. Use of Transweb to air contaminated with MS2
viruses would not achieve desired results. Thus, as can be seen in
Exhibit B, in addition to the benefits of sterilization properties
described above with respect to Exhibit A, the present invention
protects more effectively over viruses such as MS2 over time.
Because only a small amount of viruses contaminate a human (1 to
1000 viruses), unlike the present invention, Transweb does not
effectively protect a user from these viruses.
CONCLUSION
[0087] Having now described one or more exemplary embodiments of
the invention, it should be apparent to those skilled in the art
that the foregoing is illustrative only and not limiting, having
been presented by way of example only. All the features disclosed
in this specification (including any accompanying claims, abstract,
and drawings) may be replaced by alternative features serving the
same purpose, and equivalents or similar purpose, unless expressly
stated otherwise. Therefore, numerous other embodiments of the
additions and modifications thereof are contemplated as falling
within the scope of the present invention as defined by the
appended claims and equivalents thereto.
TABLE-US-00001 EXHIBIT A Experiment No AF276: Biocidal air
filtration membrane project: Performance of different filtration
membrane against BG spores for 30, 60, 120, 180, 240, 300 and 360
minutes of filtration BG 30 min 7.5 LPM DL CFU total % Reduction
2M03-01-75C+ 19.5 0.00E+00 100.00000% 2M03-01-75C+ 21.5 0.00E+00
100.00000% Transweb 17.5 1.75E+01 99.99471% C+ 21.5 3.31E+05
0.00000% BG 60 min 7.5 LPM DL CFU total % Reduction 2M03-01-75C+
21.0 0.00E+00 100.00000% 2M03-01-75C+ 20.5 0.00E+00 100.00000%
Transweb 20.0 0.00E+00 100.00000% C+ 18.5 1.49E+06 0.00000% BG 120
min 7.5 LPM DL CFU total % Reduction 2M03-01-75C+ 12.5 0.00E+00
100.00000% 2M03-01-75C+ 19.0 0.00E+00 100.00000% Transweb 6.5
1.30E+01 99.99496% C+ 16.0 2.58E+05 0.00000% BG 180 min 7.5 LPM DL
CFU total % Reduction 2M03-01-75C+ 16.0 3.20E+01 99.99924%
2M03-01-75C+ 17.0 0.00E+00 100.00000% Transweb 15.0 0.00E+00
100.00000% C+ 18.5 4.20E+06 0.00000% BG 240 min 7.5 LPM DL CFU
total % Reduction 2M03-01-75C+ 19.0 0.00E+00 100.00000%
2M03-01-75C+ 16.0 0.00E+00 100.00000% Transweb 11.0 0.00E+00
100.00000% C+ 13.0 4.21E+06 0.00000% BG 300 min 7.5 LPM DL CFU
total % Reduction 2M03-01-75C+ 13.5 2.70E+01 99.99884% 2M03-01-75C+
16.0 0.00E+00 100.00000% Transweb 9.0 0.00E+00 100.00000% C+ 9.0
2.32E+06 0.00000% BG 360 min 7.5 LPM DL CFU total % Reduction
2M03-01-75C+ 9.0 0.00E+00 100.00000% 2M03-01-75C+ 16.0 4.80E+01
99.99923% Transweb 14.0 0.00E+00 100.00000% C+ 11.0 6.20E+06
0.00000% For BG tests Challenge microorganism: BG Aerosol generated
by: 6 jets Modified Collision Nebulizer pre-vaporisation: 30 min
Air flow velocity: 7.5 LPM Nebulizer air flow: 40 PSI Filtration
time: 30 minutes Collection fluid: 5 ml of PBS with 0.001% antifoam
A Sampling on TSA 2M03-01-75C+ Non-woven + Triosyn + Electrostatic
charge Transweb Electrostatic non-woven without Triosyn DL
Detection Level
TABLE-US-00002 EXHIBIT B Biocidal air filtration membrane project:
Performance of different filtration membrane against MS2 viruses
for 60, 120, 180, 240, 300 and 360 minutes of filtration MS2 60 min
7.5 LPM DL PFU total % Reduction 2M03-01-92C+ 4.2 0.00E+00
100.00000% Transweb 4.3 1.29E+03 99.89250% C+ 4.0 1.20E+06 0.00000%
MS2 120 min 7.5 LPM DL PFU total % Reduction 2M03-01-92C+ 4.0
0.00E+00 100.00000% Transweb 2.2 1.76E+03 99.08808% C+ 4.1 1.93E+05
0.00000% MS2 180 min 7.5 LPM DL PFU total % Reduction 2M03-01-92C+
4.0 0.00E+00 100.00000% Transweb 3.5 4.23E+03 99.94125% C+ 3.6
7.20E+06 0.00000% MS2 240 min 7.5 LPM DL PFU total % Reduction
2M03-01-92C+ 3.9 0.00E+00 100.00000% Transweb 3.9 8.34E+04
99.01882% C+ 3.9 8.50E+06 0.00000% MS2 300 min 7.5 LPM DL PFU total
% Reduction 2M03-01-92C+ 4.1 0.00E+00 100.00000% Transweb 3.9
4.79E+05 96.45185% C+ 4.2 1.35E+07 0.00000% MS2 360 min 7.5 LPM DL
PFU total % Reduction 2M03-01-92C+ 3.8 0.00E+00 100.00000% Transweb
3.9 4.62E+05 97.47541% C+ 3.9 1.83E+07 0.00000% For MS2 tests
Challenge microorganism: MS2 Aerosol generated by: 6 Jets Modified
Collision Nebulizer pre-vaporisation: 30 min Air flow velocity: 7.5
LPM Nebulizer air flow: 40 PSI Filtration time: 30 min, 1, 2, 3, 4,
5 and 6 hours Collection fluid: 5 ml of PBS with 0.001% antifoam A
Sampling on MS2 media by single layer soft agar 2M03-01-92C+ Non
woven + Triosyn + Electrostatic Charge Transweb Electrostatic Non
Woven without Triosyn DL Detection Level% MS2 30 min 7.5 LPM DL PFU
total % Reduction M03-01-69-C+ 4.3 0.00E+00 100.00000% M03-01-81-C+
4.2 0.00E+00 100.00000% Transweb 4.0 2.48E+02 99.99757% C+ 3.9
1.02E+07 0.00000% For MS2 tests Challenge microorganism: MS2
Aerosol generated by: 6 jets Modified Collision Nebulizer
pre-vaporisation: 30 min Air flow velocity: 7.5 LPM Nebulizer air
flow: 40 PSI Filtration time: 30 minutes Collection fluid: 5 ml of
PBS with 0.001% antifoam A Sampling on MS2 media by single layer
soft agar M03-01-69-C+ Non woven + Triosyn + Electrostatic Charge
Transweb Electrostatic non-woven without Triosyn DL Detection
Level
* * * * *