US20120291787A1 - Biohazard Mask Filter - Google Patents
Biohazard Mask Filter Download PDFInfo
- Publication number
- US20120291787A1 US20120291787A1 US13/568,600 US201213568600A US2012291787A1 US 20120291787 A1 US20120291787 A1 US 20120291787A1 US 201213568600 A US201213568600 A US 201213568600A US 2012291787 A1 US2012291787 A1 US 2012291787A1
- Authority
- US
- United States
- Prior art keywords
- layer
- ptfe
- filter
- ptfe layer
- exhalation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- A—HUMAN NECESSITIES
- A41—WEARING APPAREL
- A41D—OUTERWEAR; PROTECTIVE GARMENTS; ACCESSORIES
- A41D13/00—Professional, industrial or sporting protective garments, e.g. surgeons' gowns or garments protecting against blows or punches
- A41D13/05—Professional, industrial or sporting protective garments, e.g. surgeons' gowns or garments protecting against blows or punches protecting only a particular body part
- A41D13/11—Protective face masks, e.g. for surgical use, or for use in foul atmospheres
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D39/00—Filtering material for liquid or gaseous fluids
- B01D39/14—Other self-supporting filtering material ; Other filtering material
- B01D39/16—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres
- B01D39/1692—Other shaped material, e.g. perforated or porous sheets
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
- B01D2239/04—Additives and treatments of the filtering material
- B01D2239/0442—Antimicrobial, antibacterial, antifungal additives
Definitions
- This invention relates to filter media for masks which protect against biological hazards.
- antimicrobial chemical is added in sufficient effective doses, for example, an agent like REPUTEX which works within the spunbond material to control the growth of microbes.
- the PTFE pore size is preferable 0.1 to 0.4 microns, and most preferably 0.2 microns, in order to allow maximum transmission of water vapor, with minimum chance for passage of bacterial or viral matter.
Abstract
An exhalate filter medium for a biohazard mask is made of polytetrafluoroethylene (PTFE) and surrounding layers of a wicking material and an antimicrobial material. The exhalate filter may be contained in a removable and replaceable cartridge snap-fit into the surface of a biohazard mask.
Description
- This application is a continuation-in-part, claiming priority to application Ser. No. 10/459,417, filed Jun. 11, 2003, “BIOHAZARD MASK SUITABLE FOR CIVILIANS.” The disclosure of the '417 application is incorporated herein by reference.
- This invention relates to filter media for masks which protect against biological hazards.
- Recent developments in antimicrobial respirators have taken the approach of filtering exhaled breath as well as inhaled breath (U.S. Pat. No. 6,584,976 B2, issued to Japuntich et al.; '417 application, filed by Freriks et al.; both incorporated herein by reference). By filtering exhalation, the wearer is prevented from exhaling both biologic entities such as bacteria and viruses into the environment where they can contaminate their surroundings and infect other people. Also, they are prevented from exhaling particles which would disturb or contaminate environments that are intended to be particularly clean such as pharmaceutical or nanotechnology production facilities.
- Unfortunately, there would be problems to overcome with this approach to filtering. In particular, the filtering of exhalation would likely result in moisture build up in the filter media making the pressure drop (resistance) to exhalation extremely high and making respiration difficult. This would result in frequent changes of respirators or filters and exposing wearer's and others to unwanted contamination. This is particularly true if the filter media is comprised of typical HEPA filtering material comprised of non-woven fibers. These media would become saturated with water vapor from the wearers' exhalation and would have to be changed on a frequent basis.
- It is desirable therefore to have an exhalation filter unit for respirators or masks which could maintain low pressure drop, (i.e., low exhalation resistance) and superior moisture vapor transmission rate while trapping bacteria and viruses in the interior of the filter.
- Modern membrane technologies have resulted in HEPA level filtration characteristics with very low resistance, but none has been designed specifically for the filtering of human exhalation or use in respirators which accomplish this purpose. Developments in membrane technology by Gore and others (e.g., U.S. Pat. No. 4,187,390, incorporated herein by reference) have shown that extremely high rates of moisture vapor transmission can be achieved using modern membrane manufacturing technologies. However, this moisture vapor transmission (MVT) capability has not been integrated with HEPA (High Efficiency Particulate filtration) level filtration related to antimicrobial filtration, particularly with regard to the filtering of human exhalation until the present invention.
- Processes for making porous PTFE membranes having customized and uniform pore size are known (e.g., U.S. Pat. No. 5,910,277 to Ishino et al., incorporated herein by reference), as are inhalation filter units employing PTFE membranes (e.g., U.S. Pat. No. 6,309,438, to Kanno et al). Missing in the art is the use of PTFE membranes which meet the specialized requirements for exhalation filters, namely, HEPA level filtration of bacterial and viral matter, coupled with pressure drop and high MVT.
- The filter material itself is not the only feature of a filter unit requiring special design consideration for exhalation. The physical structure of an exhalation filter also requires attention. In a biohazard mask suitable for civilian use (or any other mask requiring filtering), the filter unit structure should be easily replaceable, with minimum discomfort to the user during replacement but maximum safety during quarantine conditions.
- The present invention accommodates the above-mentioned goals through a number of design features, appearing as recited in various instances and combinations in the appended claims. Generally the present invention relates to a filter wherein the moisture vapor transmission efficiency has been improved by using a porous PTFE film with a specific pore diameter. The moisture vapor transmission can also be unproved by the use of coatings or layers that enhance either or both of the wicking and evaporative qualities of the PTFE material, or the anti-biologic and anti-viral properties of the filter (e.g., using biocidal materials).
- The present invention also contemplates, in another embodiment, a pair of horseshoe shaped filter cartridges, just below the nose portion of the mask. These cartridges rest inset into the surface of the mask, but external to the valve assembly (which is integral to the mask). One horseshoe-shaped filter cartridge is for inhalation, and one for exhalation. The cartridges are snap-fit (in any manner known in the art), and can be ejected (popped out) by pushing a button, or any other suitable mechanical actuator.
- One embodiment (embodiment 1) of the present invention is a polytetrafluoroethylene porous film between two layers of nonwoven polyolefin spun bond which is impregnated with antimicrobial chemicals on the interior side of the filtering element. The purpose of the antimicrobial additives is to provide a lethal environment for biologics trapped in the media. Hence, this embodiment involves three layers. The middle layer is PTFE. This is sandwiched by layers of spun bond, known in the art to give rigidity to the PTFE membrane. On the layer intended to be on the face-side of the mask (for exhalate) or the ambient side of the mask (for inhalate), antimicrobial chemical is added in sufficient effective doses, for example, an agent like REPUTEX which works within the spunbond material to control the growth of microbes. In this embodiment and all of the others herein, the PTFE pore size is preferable 0.1 to 0.4 microns, and most preferably 0.2 microns, in order to allow maximum transmission of water vapor, with minimum chance for passage of bacterial or viral matter.
- Another embodiment (embodiment 2) involves the same three layer structure as embodiment 1, but instead of antimicrobial coatings, there is added a wicking material to the spun bond on the ambient side of the exhalation filter. Such wicking materials may include the DP-988 Synthetic-Fiber Hydrophilic Finishing Agent, manufactured by Zhangjiagang Duplus Chemical Co., or similar chemicals manufactured by Daiwa Corporation, Japan. These chemicals have the effect of improving the transmissivity of water vapor away from the filter unit.
- Another embodiment (embodiment 3) involves combining embodiments 1 and 2 into a single exhalation filter, in which one side of the membrane has spun bond impregnated with a wicking material, and the other side of the membrane has spun bond impregnated with an antimicrobial material.
- Another embodiment (embodiment 4) involves a four-or-five layer filter medium according to the respective teachings of embodiments 1 through 3. In this embodiment, one or more of the spun bond layers sandwiching the PTFE membrane may be inert/uncoated. The various wicking and antimicrobial functions described with respect to embodiments 1 through 3 would be accomplished by adding an entirely new layer, as desired. For example, there may be a five layer filter medium for an exhalation filter with the top layer (exposed to the ambient) containing the wicking material, the layer below that spun bond, the layer below that a PTFE membrane, the layer below that another spun bond layer, and finally the bottom layer (exposed to the wearer's exhalate) containing the antimicrobial material. These additional layers may themselves be a base of spun bond, or may be any other material suitable for holding the applicable chemicals while exhibiting low pressure drop to easily pass breath.
- All of the foregoing embodiments may be included in a filter cartridge structure designed for easy replaceability. Preferably, the filter cartridge is in the shape of a horseshoe, and has an internal volume (about 1½ inches thick) containing the appropriate filter medium. The exterior surface of the cartridge includes a grill. The cartridges sit on the surface of the mask, just under the nose portion. One is for inhalation, and is removably seated on the mask. One is for exhalation, and is removably seated on the mask. The seating is preferably a snap-fit, where buttons on the mask will permit pop-out removal of each respective filter cartridge. Other mechanical actuators are also contemplated, e.g., catch releases, slides, etc.
- Pop-out ejection of filter cartridges, coupled with snap-fit insertions, permit quick changes. This can be important during quarantine conditions, both for comfort and for the safety of self and others.
- It will be appreciated that those skilled in the art may now make many uses and modifications of the specific embodiments described without departing from the inventive concepts. The recitation of the features and characteristics of the embodiments shown above is not meant to be limiting, but rather exemplary, with the appended claims and their equivalents defining the patentee's property rights hereunder.
Claims (10)
1-5. (canceled)
6. An exhalation filter medium having an ambient side and a face side, the medium comprising:
(a) a PTFE layer,
(b) a first nonwoven polyolefin spun bond layer positioned on the PTFE layer on the ambient side of the medium and including a wicking material;
(c) a second nonwoven polyolefin spun bond layer positioned on the PTFE layer on the face side of the medium and the layer being impregnated with an antimicrobial material; and
(d) a third nonwoven and uncoated polyolefin layer positioned between the first layer and the PTFE layer or positioned between the second layer and the PTFE layer.
7. The filter medium of claim 6 further comprising a third nonwoven polyolefin layer positioned between the second layer and the PTFE layer and attached to both layers.
8. The filter medium of claim 7 further comprising a fourth nonwoven polyolefin layer positioned between the first layer and the PTFE layer and attached to both layers.
9. The filter medium of claim 8 wherein the fourth layer is inert.
10. The filter medium of claim 6 , wherein the PTFE layer has pore sizes within a range of 0.1-0.4 microns.
11. The filter medium of claim 6 , wherein the PTFE layer has pore sizes of 0.2 microns.
12. A biohazard mask including separate inhalation and exhalation filters, the biohazard mask comprising:
a plurality of receptacles for the holding at least a first filter cartridge containing an inhalation filter and a second filter cartridge containing an exhalation filter;
the exhalation filter comprising:
(a) a PTFE layer;
(b) a first nonwoven polyolefin spun bond layer positioned on the PTFE layer and including a wicking material;
(c) a second nonwoven polyolefin spun bond layer positioned on the PTFE layer and being impregnated with an antimicrobial material; and
(d) a third nonwoven and uncoated polyolefin layer positioned between the first layer and the PTFE layer or positioned between the second layer and the PTFE layer.
13. The biohazard mask of claim 12 , wherein the PTFE layer has a pore size within the range of 0.1-0.4 microns.
14. The biohazard mask of claim 13 , wherein the PTFE layer has a pore size of 0.2 microns.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/568,600 US20120291787A1 (en) | 2003-06-11 | 2012-08-07 | Biohazard Mask Filter |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/459,417 US7152600B2 (en) | 2003-01-22 | 2003-06-11 | Biohazard mask suitable for civilians |
US86123104A | 2004-06-03 | 2004-06-03 | |
US13/025,376 US20110132373A1 (en) | 2003-06-11 | 2011-02-11 | Biohazard Mask Filter |
US13/568,600 US20120291787A1 (en) | 2003-06-11 | 2012-08-07 | Biohazard Mask Filter |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/025,376 Continuation US20110132373A1 (en) | 2003-06-11 | 2011-02-11 | Biohazard Mask Filter |
Publications (1)
Publication Number | Publication Date |
---|---|
US20120291787A1 true US20120291787A1 (en) | 2012-11-22 |
Family
ID=36777649
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/025,376 Abandoned US20110132373A1 (en) | 2003-06-11 | 2011-02-11 | Biohazard Mask Filter |
US13/568,600 Abandoned US20120291787A1 (en) | 2003-06-11 | 2012-08-07 | Biohazard Mask Filter |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/025,376 Abandoned US20110132373A1 (en) | 2003-06-11 | 2011-02-11 | Biohazard Mask Filter |
Country Status (10)
Country | Link |
---|---|
US (2) | US20110132373A1 (en) |
EP (1) | EP1768751B1 (en) |
JP (1) | JP2008501432A (en) |
CN (1) | CN1980711A (en) |
AT (1) | ATE458536T1 (en) |
CA (1) | CA2569669C (en) |
DE (1) | DE602005019571D1 (en) |
IL (1) | IL179776A (en) |
MX (1) | MXPA06013970A (en) |
WO (1) | WO2006083287A2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102020109503A1 (en) | 2020-04-06 | 2021-10-07 | Thierry Lucas | Infection protection mask for hygiene applications |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090211581A1 (en) * | 2008-02-26 | 2009-08-27 | Vishal Bansal | Respiratory mask with microporous membrane and activated carbon |
JP5268432B2 (en) * | 2008-05-30 | 2013-08-21 | 小林製薬株式会社 | Absorbent core and mask containing the same |
US20130185850A1 (en) * | 2012-01-23 | 2013-07-25 | Atomic Energy Council - Institute Of Nuchear Energy Research | Protective clothing with ventilation effect |
US20210298384A1 (en) * | 2020-03-25 | 2021-09-30 | Nclosd Masks Llc | Surgical mask |
CN111991718B (en) * | 2020-07-07 | 2021-05-11 | 东阳市汉宸膜技术有限公司 | Medical head-wearing purification mask combined with polytetrafluoroethylene membrane and preparation method thereof |
US11123584B1 (en) | 2020-10-05 | 2021-09-21 | Iowa State University Research Foundation, Inc. | Personal protective anti-viral face mask |
US11375761B2 (en) * | 2020-11-12 | 2022-07-05 | Chi Chen HSIEN | Electrochemical antimicrobial face mask |
Citations (14)
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US4094669A (en) * | 1976-01-02 | 1978-06-13 | Basf Wyandotte Corporation | Polytetrafluoroethylene membrane filters for mercury recovery |
US4187390A (en) * | 1970-05-21 | 1980-02-05 | W. L. Gore & Associates, Inc. | Porous products and process therefor |
US5108474A (en) * | 1991-01-03 | 1992-04-28 | W. L. Gore & Associates, Inc. | Smoke filter |
US5669375A (en) * | 1995-09-21 | 1997-09-23 | Dragerwerk Aktiengesellschaft | Breathing mask |
US5910277A (en) * | 1996-05-17 | 1999-06-08 | Nitto Denko Corporation | Process of making a porous PTFE membrane |
US6130175A (en) * | 1997-04-29 | 2000-10-10 | Gore Enterprise Holdings, Inc. | Integral multi-layered ion-exchange composite membranes |
US6309438B1 (en) * | 1998-11-16 | 2001-10-30 | Mine Safety Appliances Company | Filter unit and dust-proof mask therewith |
US6514325B2 (en) * | 2000-03-15 | 2003-02-04 | Hollingsworth & Vose Company | Melt blown composite HEPA vacuum filter |
US6584976B2 (en) * | 1998-07-24 | 2003-07-01 | 3M Innovative Properties Company | Face mask that has a filtered exhalation valve |
US20030203696A1 (en) * | 2002-04-30 | 2003-10-30 | Healey David Thomas | High efficiency ashrae filter media |
US6723428B1 (en) * | 1999-05-27 | 2004-04-20 | Foss Manufacturing Co., Inc. | Anti-microbial fiber and fibrous products |
US6808553B2 (en) * | 2001-06-13 | 2004-10-26 | Nitto Denko Corporation | Filter medium for turbine and methods of using and producing the same |
US20040226563A1 (en) * | 2003-05-12 | 2004-11-18 | Zhaoxia Xu | Face Mask with Double Breathing Chambers |
US7152600B2 (en) * | 2003-01-22 | 2006-12-26 | Biokidz Usa Nfp | Biohazard mask suitable for civilians |
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EP0159697A3 (en) * | 1984-04-27 | 1987-01-14 | Pall Corporation | Gas mask canister |
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DE8815460U1 (en) * | 1988-12-13 | 1989-03-23 | Gerigk, Wolfgang, 2000 Norderstedt, De | |
WO1998033403A1 (en) * | 1997-01-31 | 1998-08-06 | Tecnol Medical Products, Inc. | Non-particulating and low particulating disposable products for use in clean room environments |
-
2005
- 2005-06-03 CA CA2569669A patent/CA2569669C/en not_active Expired - Fee Related
- 2005-06-03 CN CNA2005800178484A patent/CN1980711A/en active Pending
- 2005-06-03 WO PCT/US2005/019561 patent/WO2006083287A2/en active Search and Examination
- 2005-06-03 AT AT05856783T patent/ATE458536T1/en not_active IP Right Cessation
- 2005-06-03 EP EP05856783A patent/EP1768751B1/en not_active Not-in-force
- 2005-06-03 MX MXPA06013970A patent/MXPA06013970A/en unknown
- 2005-06-03 DE DE602005019571T patent/DE602005019571D1/en not_active Expired - Fee Related
- 2005-06-03 JP JP2007515616A patent/JP2008501432A/en active Pending
-
2006
- 2006-11-30 IL IL179776A patent/IL179776A/en not_active IP Right Cessation
-
2011
- 2011-02-11 US US13/025,376 patent/US20110132373A1/en not_active Abandoned
-
2012
- 2012-08-07 US US13/568,600 patent/US20120291787A1/en not_active Abandoned
Patent Citations (15)
Publication number | Priority date | Publication date | Assignee | Title |
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US4187390A (en) * | 1970-05-21 | 1980-02-05 | W. L. Gore & Associates, Inc. | Porous products and process therefor |
US4094669A (en) * | 1976-01-02 | 1978-06-13 | Basf Wyandotte Corporation | Polytetrafluoroethylene membrane filters for mercury recovery |
US5108474A (en) * | 1991-01-03 | 1992-04-28 | W. L. Gore & Associates, Inc. | Smoke filter |
US5669375A (en) * | 1995-09-21 | 1997-09-23 | Dragerwerk Aktiengesellschaft | Breathing mask |
US5910277A (en) * | 1996-05-17 | 1999-06-08 | Nitto Denko Corporation | Process of making a porous PTFE membrane |
US6030428A (en) * | 1996-05-17 | 2000-02-29 | Nitto Denko Corporation | Porous polytetrafluoroethylene membrane, process for producing the same, sheet-form polytetrafluoroethylene molding, and air filter medium |
US6130175A (en) * | 1997-04-29 | 2000-10-10 | Gore Enterprise Holdings, Inc. | Integral multi-layered ion-exchange composite membranes |
US6584976B2 (en) * | 1998-07-24 | 2003-07-01 | 3M Innovative Properties Company | Face mask that has a filtered exhalation valve |
US6309438B1 (en) * | 1998-11-16 | 2001-10-30 | Mine Safety Appliances Company | Filter unit and dust-proof mask therewith |
US6723428B1 (en) * | 1999-05-27 | 2004-04-20 | Foss Manufacturing Co., Inc. | Anti-microbial fiber and fibrous products |
US6514325B2 (en) * | 2000-03-15 | 2003-02-04 | Hollingsworth & Vose Company | Melt blown composite HEPA vacuum filter |
US6808553B2 (en) * | 2001-06-13 | 2004-10-26 | Nitto Denko Corporation | Filter medium for turbine and methods of using and producing the same |
US20030203696A1 (en) * | 2002-04-30 | 2003-10-30 | Healey David Thomas | High efficiency ashrae filter media |
US7152600B2 (en) * | 2003-01-22 | 2006-12-26 | Biokidz Usa Nfp | Biohazard mask suitable for civilians |
US20040226563A1 (en) * | 2003-05-12 | 2004-11-18 | Zhaoxia Xu | Face Mask with Double Breathing Chambers |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102020109503A1 (en) | 2020-04-06 | 2021-10-07 | Thierry Lucas | Infection protection mask for hygiene applications |
Also Published As
Publication number | Publication date |
---|---|
WO2006083287A3 (en) | 2007-02-22 |
IL179776A0 (en) | 2007-05-15 |
JP2008501432A (en) | 2008-01-24 |
EP1768751A2 (en) | 2007-04-04 |
CA2569669A1 (en) | 2006-08-10 |
IL179776A (en) | 2010-12-30 |
CA2569669C (en) | 2014-01-07 |
CN1980711A (en) | 2007-06-13 |
ATE458536T1 (en) | 2010-03-15 |
US20110132373A1 (en) | 2011-06-09 |
EP1768751A4 (en) | 2007-09-12 |
MXPA06013970A (en) | 2007-10-23 |
EP1768751B1 (en) | 2010-02-24 |
WO2006083287A2 (en) | 2006-08-10 |
DE602005019571D1 (en) | 2010-04-08 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |