This present invention is directed to a disposable protective garment for positioning over a wearer's head, desirably for use in airline travel, bus and subway travel, voting booths, convention halls and other temporary use applications. The invention is also directed to a protective barrier film that can be used to make the disposable protective garment and also has other uses involving barrier properties.
The coronavirus pandemic has generated a need or desire for masks, gloves and other protective equipment that limit exposure between a user and his or her surrounding environment. Conventional masks can be both awkward and uncomfortable for the consumer-wearer, often requiring adjustment to allow enough air flow for breathing and to minimize fogging of glasses. Because conventional masks are typically held in place by loop attachments that encircle the wearer's ears, there is no one size that fits all users and protection is limited to due to variations in size of the users' heads and distance between users' faces and ears. There is also an inverse relationship between the flow of air needed for comfortable breathing and the amount of protection provided by the mask. If the mask is adjusted to enable comfortable breathing, the degree of protection is reduced. If the mask is adjusted to provide maximum protection, the flow of air is inhibited to make breathing difficult and uncomfortable. Masks that are designed to provide both high protection and more comfortable breathing are typically too expensive for everyday consumer use and/or for disposal after a single use. Moreover, masks that are designed for multiple uses can accumulate bacteria and virus growth within the masks, thereby defeating their purpose to a large degree.
There is a need or desire for a protective item that is inexpensive, effective, and designed for disposal after a single use.
There is also a need or desire for an inexpensive disposable protective item that provides adequate protection from viruses and bacteria without significantly interfering with the wearer's breathing.
There is also a need or desire for a protective item that operates in cooperation with the flow of air in airplanes, busses, trains and other mass transit to inhibit viruses and bacteria from entering the protective item and affecting its user.
The present invention is directed to a low-cost disposable protective garment for positioning over a wearer's head that is lightweight, easy to store and distribute, and can, if desired, be disposed of and recycled after a single use. The disposable protective garment is comfortable to the wearer, provides a clear path of vision, and provides ease of breathing while protecting the user from external viruses and bacteria as well as protecting others from the user's own breathing.
In one embodiment, the invention is directed to a disposable protective garment for positioning on a wearer's head that includes the following elements:
a protective hood formed of a tubular film and having an at least partially closed or covered top end and a slanted open bottom end;
the top end further including at least one of an uncovered open portion, one or more openings in a covered portion, and a porous cover material for receiving inlet air and passing it from the top end to the bottom end;
the slanted bottom end being open to receive a wearer's head.
The foregoing disposable protective garment can be combined and/or integrated with a mask, a rigid or semi-rigid crown, an inlet air filter and/or a fan-driven tubular filter as described below and can also include a headgear. In another embodiment, the invention is directed to a disposable protective garment that includes the following elements:
a protective hood formed of a tubular film and having a filtered top end and a slanted open bottom end;
the top end being at least partially closed or covered to rest on top of a wearer's head;
the top end further including an air filter material for filtering air received through the top end, at least partially covering the top end;
the slanted bottom end being open to receive the wearer's head.
In another embodiment, the invention is directed to a transparent multilayer coextruded film for use in forming a disposable protective garment. The transparent multilayer film includes the following elements:
first and second outer layers formed using a transparent polyester or polyester copolymer;
an inner layer formed using a low density polyethylene or linear low density polyethylene having low crystallinity; and
adhesive layers between each of the two outer layers and the inner layer;
wherein the film has a light transmission of at least about 80%.
With the foregoing in mind, it is a feature and advantage of the invention to provide a disposable protective garment for positioning on a wearer's head that is lightweight, inexpensive, disposable, and useful in a wide variety of mass transit application and other single use applications.
It is also a feature and advantage to provide a disposable protective garment for positioning on a wearer's head that provides ample protection to the wearer and others around him or her without creating inconvenience and discomfort.
The foregoing and other features and advantages will become further apparent from the following detailed description of the invention, read in conjunction with the drawings.
Referring to
Airplanes, commercial busses, trains and other large mass transit carriers often blow fresh and/or filtered air from the top of the cabin and downward toward each passenger. The hood and mask combination 10 is suitably designed to work in cooperation with this clean air flow. Accordingly, the top end 14 of the hood 12 is typically partially opened and partially closed or covered to enable the hood to receive the clean air flow while maintaining the position of the hood 12 on the wearer's head. The partial closure can be formed by heat sealing the tubular film 14 to itself, by gluing, by threading and tightening a ribbon or string through the top end 14, or by any suitable technique. The top end can also be partially twisted shut to leave a partial opening, or completely twisted shut followed by slitting to leave a partial opening. The top end 14 of the hood 12 is suitably about 25% to about 75% closed or covered and about 25% to about 75% opened, or about 40% to about 60% closed or covered and about 40% to about 60% opened. The open portion of the top end 14 can be located toward the front side 18 of the hood 12 so that the clean air from the top of the cabin is directed through the opening and toward the wearer's face, or can be located toward the back side 20 of the hood 12 to provide a more tortuous path for the clean air before it reaches the wearer's face.
The slanted open bottom end 16 of the hood 12 provides enhanced protection of the wearer's face by minimizing any backflow of air through the bottom end towards the wearer's face and breathing passages. Due to the clean air being directed downward from the top of the mass transit cabin, the flow of clean air through the hood 12 is typically from top to bottom. However, the open bottom end 16 can nevertheless permit some backflow, especially when the wearer disengages of blocks the flow of clean air from above. The longer front side 18 of the hood 12 which results from the slanted bottom end 16 minimizes the amount of backflow that reaches the wearer's face. In one embodiment, a ribbon or string (not shown) can be threaded through at least a portion of the slanted bottom end 16 and can be tightened to pull the longer front side 18 of the bottom end 16 of the hood 12 closer to the wearer.
A mask 22 is combined with the hood 12 by forming a plurality of apertures 24 in the hood, suitably in a rectangular pattern as shown. A filter material 26, which can be a strip of polymer fabric, is bonded to the tubular plastic film 13 that defines the hood 12 by heat sealing, gluing, or another suitable attachment technique. The filter material 26, which can be a rectangular strip as shown, completely covers the apertures 24 and the regions immediately surrounding the apertures 24. The mask 22 is thus defined by the plurality of apertures 24 in the tubular film 13 and the laminated filter material 26 covering the apertures 24. A first strip of filter material 26 can be bonded to one of the inside and the outside surface of the tubular film 13. If desired, a second strip of filter material 26 can be bonded to the other of the inside and the outside surface of the tubular film 13 to provide improved filtration.
The apertures 24 can be circular as shown, square, rectangular, oval, elliptical, of can have any suitable shape. The apertures 24 should be large enough to enable free passage of air yet small enough so as not to interfere with the structural integrity of the hood 12. Depending on their shape, the apertures 24 can have a diameter, length, or other dimension ranging from about 0.1 inch to about 1.5 inch, suitably about 0.5 inch to about 1.0 inch. The mask 22 can be positioned on the front side 18 of the hood 12 as shown in
The tubular film 13 forming the hood 12 can be a coextruded film, such as coextruded barrier film that possesses moisture barrier and some air barrier. The coextruded film can include a barrier layer having a first side and a second side, a first heat seal layer on the first side of the barrier layer, and a first tie layer bonding the first heat seal layer to the barrier layer. Additionally, the coextruded film can have a second heat seal layer on the second side of the barrier layer and a second tie layer bonding the second heat seal layer to the barrier layer.
The barrier layer can be formed of a polyolefin that offers moisture barrier and suitable air barrier for the duration of use of the protective hood and mask combination 10. Suitable polyolefins include without limitation linear low-density polyethylene, linear medium density polyethylene, branched low density polyethylene, polypropylene, and combinations thereof. Linear low-density polyethylene is particularly suitable for most applications.
The first heat seal layer and, if included, the second heat seal layer can be formed using a polyester copolymer. Suitable polyester copolymers include without limitation polyethylene terephthalate glycol, polyethylene terephthalate-1,4-cyclohexane-2 methyl ester, polyester-polyether block copolymers, and combinations thereof. Polyethylene terephthalate glycol (PETG) is particularly suitable for one or both of the heat seal layers.
The first adhesive tie layer and, if included, the second adhesive tie layer can be formed of a soft polymer that exhibits tackiness. Suitable soft polymers include without limitation ethylene methyl acrylate, ethylene ethyl acrylate, ethylene methacrylic acid, ethylene ethyl acrylate, and combinations thereof. Ethylene methyl acrylate and ethylene ethyl acrylate are particularly suitable for one or both of the adhesive tie layers.
The filter material 26 used to form the mask 24 can be formed using a polymer fabric. Suitable polymer fabrics include without limitation polyester fabrics, polyamide fabrics, cellulose fabric, and combinations thereof. Polyester fabrics are particularly suitable.
In a relatively simple embodiment, the protective hood need only include a tubular film 13, suitably having a partly closed top end 14 for resting on a wearer's head and an open bottom end 16 for resting on a wearer's shoulders. Adequate ventilation can be achieved by passing clean cabin air through the partly open top end, downward and out through the open bottom end. In simple and more complex embodiments, the tubular film 13 forming the hood 12 can have a more complex layer structure that provides comfort, clarity, relatively low cost and excellent heat seal properties. One exemplary complex layer structure includes a five-layer arrangement having two outer layers of polyester homopolymer or copolymer, and inner layer of polyethylene, and adhesive layers joining each of the outer layers to the inner layer. One suitable multilayer film includes the five-layer sequence PETG/EEA/PE/EEA/PETG. The PETG (polyethylene terephthalate glycol) is an amorphous polyester copolymer that provides high clarity and softness and is excellent for heat sealing. The EEA (ethylene ethyl acrylate) provides the film with adhesive tie layers for bonding the PETG on both sides to the PE (polyethylene) layer. The polyethylene layer can be a low density or linear low density polyethylene, suitably one that has low crystallinity. Conventional (branched) low density polyethylene resins typically have crystallinities ranging from about 35% to about 55%, measured using ASTM D1505, and densities of about 0.910 to about 0.925 grams/cm3. Linear low-density polyethylene resins typically have crystallinities ranging from about 35% to about 60% and densities of about 0.910 to about 0.925 grams/cm3. The polyethylene layer should be selected to have a crystallinity at the lower end of the range, suitably about 35% to about 45%, or about 35% to about 40%.
The polyethylene serves as the structural layer that provides the tubular film 13 with sufficient overall strength for its intended uses. Because of its low crystallinity, the polyethylene layer has low internal haze. When its surfaces are covered with the relatively clear EEA and PETG film layers, the overall tubular film 13 is very clear. Film clarity is a measure of percent light transmittance and can be measured using ASTM D1746. For example, when a film is exposed to 100% of an incident light source, the transmittance is 100% minus (percent absorption+percent reflection). For optimal use and wearer comfort, the tubular film 13 should have a light transmittance of at least about 80%, suitably at least about 84%, or at least about 88%.
The foregoing film can also be used as a barrier film having high transparency in a wide variety of barrier applications including, but not limited to the protective garment. In one embodiment, the barrier film can include an oxygen barrier layer such as an internal layer of ethylene vinyl alcohol, which can be positioned between the polyethylene structural layer and one of the outer polyester homopolymer or copolymer (e.g., PETG) layers. The ethylene vinyl alcohol (EVOH) layer is joined on both sides with an adhesive tie layer. The adhesive tie layer used to bond the EVOH can also be EEA but is suitably a blend of EEA and an anhydride-modified polyolefin, for example PLEXAR® available from MSI Technology, LLC. Adhesive blends can include about 25% to about 75% by weight EEA and about 25% to about 75% by weight anhydride-modified polyolefin, or about 40% to about 60% by weight of each component, or about 50% by weight of each component. Exemplary high barrier film structures that exhibit excellent clarity include without limitation PETG/adhesive blend/EVOH/adhesive blend/PE/EEA/PETG; PETG/EEA/PE/adhesive blend/EVOH/adhesive blend/PETG; and PETG/adhesive blend/EVOH/adhesive blend/PE/adhesive blend/PETG.
A shown in
The air filter material 34 can be attached to the hood 12 using heat sealing (e.g., heat and pressure), adhesive lamination, stitching, sewing and/or other suitable techniques. When the hood is formed using one or more outer heat seal layers as described above, such as the above-described five-layer arrangement of PETG/EEA/PE/EEA/PETG, the air filter material can be heat sealed or otherwise attached to the inside or the outside of the hood 12, or to both the inside and the outside of the hood 12.
In embodiments of the protective garment 10 when the headgear 40 and protective hood 12 are either unconnected or connected together, the headgear can define the at least partially closed portion of the protective hood 12. In these embodiments, the protective hood 12 illustrated in
The protective garment 10 can be provided as a two-piece assembly in which the protective hood 12 can remain unconnected or be temporarily connected to the headgear 40 at one or more intermittent locations using tape, glue, hook-and-loop fasteners, pins, or another temporary fastening means or device. In these embodiments, the headgear 40 can be re-used several times and the protective hood 12 can be replaced more frequently, such as after every use. In one embodiment, the protective garment 10 can be sold as a kit that includes one or a small number of headgears 40 and a much larger number of disposable protective hoods 12. Whereas one function of the headgear 40 is to maintain adequate distance between the protective hood 12 and the user's face, the components can be sized and shaped so that the protective hood 12 fits over the headgear 40. Whereas one function of the protective garment 10 is to prevent the protective hood 12 from sliding downward across the user's face, the protective hood 12 can either be designed with a seal 42 as shown in
By maintaining a suitable distance between the front 18 of the hood 12 and the wearer's face, ventilation within the protective garment 10 can be greatly improved. Fogging of the protective hood 12 due to a wearer's exhaled breath can be minimized or eliminated. Talking can become clearer without the muted or muffled effect that a mask or clinging film may create. The combination of protective hood 12 and headgear 40 also creates a more tortuous path for air entering through the open region 44 of the top 14 of hood 12 (
The protective hood 12 can be formed using a standard blown film process which forms a continuous tubular film and typically flattens the film between rollers.
While the embodiments of the invention described herein are exemplary, various modifications and improvements can be made without departing from the spirit and scope of the invention. The scope of the invention is defined by the appended claims and all changes that fall within the meaning and range of equivalents are intended to be embraced therein.
This patent application claims priority based on U.S. Provisional Application 63/027,715, filed on May 20, 2020; U.S. Provisional Application 63/116,695, filed on Nov. 23, 2020; and U.S. Provisional Application 63/123,588, filed on Dec. 10, 2020. The disclosures of these provisional applications are incorporated herein by reference.
Number | Date | Country | |
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63027715 | May 2020 | US | |
63116965 | Nov 2020 | US | |
63123588 | Dec 2020 | US |