MXPA01008315A - Flat-folded personal respiratory protection devices and processes for preparing same - Google Patents

Abstract

Respiratory devices having first and second lines of demarcation bisected by a fold. The devices are capable of being folded in a first substantially flat configuration for storage (e.g., in a pocket) and are capable of being unfolded in a second ready-to-wear configuration so that a portion of the device covering the nose and the mouth is off-the-face. Processes for making such devices include folding a preform over a bisecting axis and cutting the preform at desired angles and sealing the cuts together to form the mask.

Description

PERSONAL RESPIRATORY PROTECTION DEVICES, PLUMBING BEND. AND PROCESS FOR YOUR PREPARATION DESCRIPTION OF THE INVENTION The present invention relates to personal respiratory protection devices that are capable of bending flat during storage and forming an air chamber over a user's mouth and nose when in use. Personal respiratory protection devices, also known as filtering respirators or face masks, are used in a wide variety of applications to protect the user's respiratory system from airborne particles or from unpleasant or noxious gases. Facial masks are typically designed to be used over the nose and mouth to protect the wearer from undesirable material suspended in the air. Generally, these types of facial masks come in two basic designs - a shape shaped like a molded cup or a flat folded shape. A conventional flat folded shape of a face mask is typically constructed by incorporating a fabric that is rectangular in shape and that includes at least one fold that runs generally parallel to the wearer's mouth. Such constructions may have a reinforcing element for REF: 132481 keep the facial mask away from contact with the user's face. The reinforcement has also been provided by fusing a fold across the width of the face mask into a laminated structure or by providing a seam across the width of the face mask. In many applications, it is particularly desirable to provide such a face mask having a generally "flat" configuration for easy storage prior to the placement of the face mask. The flat bent form has advantages in that it can be easily stored, for example in the user's pocket. It has been found that flat-type facial masks can be closely shaped to the user's face, that is, most of the inner surface of the mask can be brought into contact with the user's face. Therefore, flat facial masks can become warm and can be uncomfortable when used, and this is particularly true when the face mask is used for extended periods of time. In addition, the interior surface of the face mask can be brought into contact with the wearer's skin so that the face mask is often wetted and abraded. Later it happens that the worn material of the inner surface can irritate the user. Cup-shaped masks are typically molded masks that form an air chamber over the face when used to thereby solve some of the comfort concerns associated with flat bent masks. The molded cup-shaped masks, however, can not be folded flat for easy and convenient storage. U.S. Patent No. 3,971,369 to Aspelin et al., Discloses a generally cup-shaped surgical mask that is not molded. The patent discloses that because the mask is not molded, the edges of the body portion of the mask are not rigid and therefore conform to the contours of the user's face. However, the mask is complicated to manufacture and the resulting design is folded, and has material superimposed on the front of the mask. International publication number WO 96/28217 describes a flat bent personal respiratory device. In that publication, it is described that the devices include a planar central portion, a first planar member attached to the central portion through a bending, sewing, welding or joining line and a second planar member, attached to the central portion through either of the bending line, seam, welding or joining. It is described that the device is capable of bending flat for storage with the first and second members positioned on at least the partial face of the face contact with a common surface of the central portion and, during its use, it is able to form a cup-shaped air chamber over the user's nose and mouth. There is a need for a personal respiratory protection device or face mask that is capable of bending flat, and still provides a good respiratory seal and is comfortable for the user. There is an additional need for an uncomplicated design mask that is relatively easy and inexpensive to manufacture. One aspect of the present invention provides a personal respiratory protection device that includes a non-folded main body. Preferably, the main body includes a first portion, a second portion differentiated from the first portion by a first line of demarcation; a third portion differentiated from the second portion by a second line of demarcation; and a bisecting fold extending through the first portion, the second portion and the third portion; wherein the device is capable of being bent into a first substantially flat bent configuration along the bisecting bend and which is capable of being unfolded or deployed to an open convex configuration. Preferred embodiments of the device include a filter means or a cover layer, preferably, the device includes a reinforcement layer in at least the second portion. In a preferred embodiment, the device includes a welding line between the first and second portion which joins the filter means, the cover layer and preferably the reinforcing layer, together. In a particularly preferred embodiment, the device includes a second welding line between the second portion and the third portion, which joins the layers together. A device according to the present invention preferably has the first portion extending from the second portion at an angle of from about 110 ° to about 175 °, when measured from the bisecting fold, which extends through the second portion of the second portion. bisecting fold, extending through the first portion when the device is bent into a substantially flat bent configuration. A device according to the present invention preferably has a third portion extending from the second portion at an angle of about 100 ° to about 165 ° when measured from the bisecting fold extending through the second portion of the bisecting fold which extends through the third portion when the device is bent into a substantially planar bent configuration. In another aspect of the present invention, a process is described for producing respiratory devices of different sizes from preformed blank pieces of the same size. The process includes folding a preformed blank onto a bisection axis to create a preform having a bisecting fold line, and cutting the preform at a first desired angle in a first position relative to the bisecting line of doubles, wherein The first desired angle depends on the desired size and placement of the device. The size and placement of the device can be further adjusted by cutting the preform at a second desired angle at a position relative to the bisecting fold line. A device according to the present invention may also include an optional constituent such as a face cover, a face seal, a neck cover and a combination thereof. Advantageously, a flat bent face mask according to the present invention preferably makes contact with the user's face at the periphery of the facial mask at an acute angle, with minimal facial contact to form a convex or cup-shaped region over the user's nose and mouth, thereby increasing user comfort and potentially maximizing the perimeter engagement of the facial mask with the user's face. A process according to the present invention is susceptible to high speed production methods and may comprise additional steps as needed, for attachment of headbands, ear loops, nose pieces and other typical components of the devices respiratory Figure 1 is a side view of a personal respiratory protection device of the invention, in a flat bent configuration. Figure 2 is a front view of the personal respiratory protection device of Figure 1, shown in an open configuration, ready for use. Figure 3 is a schematic illustration of an exemplary manufacturing process for producing a personal respiratory protection device, flat bent. Figures 4a-4c are schematic illustrations of an assembly process utilizing a unique preform resulting from an exemplary manufacturing process of Figure 3. Figure 5 is a cross-section, taken along line 5-5 of a unique preform of figure 4a. Figure 6 is a schematic illustration of an anvil used to form the welding lines in a device according to the present invention. Figure 7 is a schematic illustration of an anvil used to form a preform in the process for making a device according to the present invention. In one embodiment of the present invention, a personal respiratory protection device 10 is preferably capable of a flat bent configuration, as shown in Figure 1. The device is preferably folded in half, along a line 18 that is extends from a first portion 34 to a third portion 36 for storage in a package, before its use in a user's pocket. In Figure 1, a half or a side view of a bent configuration of the personal respiratory protection device 10 is shown. Preferably, the device includes a main body 12, a first portion 34, a second portion 38 and a third portion 36. These portions may be provided as separate components, however, it is preferred that the first portion 34, the second portion 38 and the third portion 36 is completely integral to form a unitary main body 12. A device according to the present invention preferably also includes binding constituents, such as an ear-binding constituent 26 or a headband (not shown). For the purposes of this invention, the following terms shall have the meanings defined: "Convex open configuration" shall mean a configuration of the device in use, wherein the main body is substantially outside the user's face, although still in sealing engagement with the face to provide an air chamber over the user's nose and mouth.

"Demarcation line" shall mean a predetermined line in the main body 12 that distinguishes a portion 34, 36, 38 of the main body 12 from another. A demarcation line forms a rotation axis for one or more of the portions 34, 36, 38 to rotate at least partially around such a demarcation line. A demarcation line may or may not extend along or across the main body 12. Examples of a demarcation line include a bending line, a joint, a weld or seam line. The term "fold" means a fold wherein the material of the device is folded back on itself at least once, in a manner similar to an accordion. A "weld line" may or may not be a demarcation line. As will be described in more detail in the following, the main body 12 preferably includes multiple layers that can function to filter unwanted particles suspended in the air to protect the user from environmental irritation or to heat the incoming air, in colder climates, as the user inhales. A respiratory device according to the present invention includes a first demarcation line A and a second demarcation line B that define the second portion 38 therebetween. These demarcation lines provide two axes of rotation that extend laterally for movement of the first portion 34 around the demarcation line A, and of the third portion 36 around the second demarcation line B. That is, these demarcation lines they have a function similar to articulation that imparts movement to the first and third portions, relative to the second portion and imparts structural integrity to the second portion during use. It has been found that these demarcation lines improve the flexibility and adaptation of the device during use around the nose and cheek of the user. In a preferred embodiment, the personal respiratory device includes a multi-layer construction. In this embodiment, demarcation lines can prevent delamination of the multiple layers so that the inner layer does not collapse during use. Preferably, the demarcation lines are welds, because the welds impart good structural integrity and prevent delamination. The demarcation lines can be formed by various suitable techniques to form an axis of rotation. Suitable techniques include welding (for example ultrasonic welding) pressure application (with or without heat), application of sticks, sewing and the like. It should be understood that the lines of demarcation can be substantially continuous, discontinuous, straight, curvilinear and a combination thereof, insofar as the demarcation lines impart an axis of rotation for movement of the first portion 34 around the line of demarcation. demarcation A and the third portion 36 around the second demarcation line B. In a preferred embodiment, at least one demarcation line includes a welding line and, more preferably, both demarcation lines include welding lines. Preferably, the demarcation lines do not include and are not part of a fold. A bisecting fold 18 preferably includes a first fold 14 a second fold 14 'and a third fold 14. "An edge seal 16 extending from the first bend 14 to the third bend 14" as shown, terminates the configuration of the device. Folds 14 and 14"are preferably formed by welds, as described in the following, which may be straight or curvilinear, but which are preferably substantially straight, as shown, however, bending may be formed by other means In the art, such as sewing, the ear-binding constituent 26 is provided to hold the device in place on the face of a user, typically by securing around the user's ears.Another constituents such as a headband to a personal respiratory device, in accordance with the present invention, to hold the device in place in the user's head.

The respiratory or personal protection device 10 is shown in Figure 2, where the common parts are identified as in Figure 1, in its convex open configuration, ready to be used having the general shape of a cup or sack which It provides the user with the benefits of "removed from the face" of a "cup-shaped" breathing device. This configuration allows the user a greater degree of movement of the jaws and comfort to the user because the device is substantially not in contact with the user's face in the mouth area. According to the present invention, this configuration is preferably carried out in the absence of folds running horizontally in the main body 12. Instead, a device according to the present invention preferably includes a bisecting fold extending from the first portion to the third portion of the device, wherein the device is essentially divided into a first half and a second half. In addition to the bisecting fold, other fold lines are not necessary to obtain a substantially flat bent configuration of the device. Preferably the second central portion or portion 38 is less flexible than the first portion 34 and the third portion 36. A less flexible central portion included in a personal respiratory device according to the present invention advantageously improves the convex open configuration and therefore contributes to benefits far from the face during use. The shape and size of a personal respiratory device 10 of the present invention can vary by varying the shape and angle of the bends 14 and 14", which can be straight or curvilinear, preferably substantially straight, as desired to obtaining a good adaptation to the face of the user Folds 14 and 14"are preferably each formed by a welding line resulting in a first angle 40 and a second angle 42, from a first point of origin 44, and a second point of origin 46 along the second bend 14 ', respectively. Preferably, the first angle 40, formed and measured from the second bend 14 'to the first fold line 14, is from about 110 ° to about 175 °, more preferably from about 140 ° to about 155 °. Preferably, the second angle 42 formed and measured from the second bend 14 to the third bend line 14"is from about 100 ° to about 165 °, more preferably from about 135 ° to about 150 °. In the shape of the fold lines 14 and 14", the first angle 40 and the second angle 42, the adaptation of the respiratory device to the face can easily be altered to accommodate faces with varying sizes. A person ordinarily skilled in the art will appreciate that by varying the angles of each of the first angle 40 and the second angle 42 of the second bend 14 A the length of the first bend 14 and the third bend 14"will also vary accordingly. however, the first and third bending lines 14 and 14 typically vary within a length range from about 40 mm to about 80 mm, wherein the first bending line and the third bending line do not necessarily have the same length . In view of the foregoing, a personal respiratory device in accordance with the present invention typically has a height (measured from the outer edge of the first portion to the outer edge of the second portion) in the convex open configuration of from about 90 mm to about 160 mm, preferably from about 100 mm to about 150 mm, and more preferably from about 110 mm to about 140 mm. The height of the second portion 38 of the respiratory device 10 formed between the demarcation lines A, A 'and B, BJ is preferably from about 30 mm to about 100 mm in height, more preferably from about 35 mm to about 75 mm in height, and most preferably from about 45 mm to about 65 mm in height. height. Additionally, a personal respiratory device according to the present invention typically has a width (measured from the outer edge of the right edge seal to the outer edge of the left edge seal) in the convex open configuration from about 110 mm to about 190 mm, preferably from about 130 mm to about 170 mm, and more preferably from about 140 mm to about 160 mm. As briefly mentioned above, a personal respiratory device according to the present invention preferably includes a multi-layer construction having at least one cover layer and one filter layer. An optional reinforcing layer can also be included. The filter layer includes a medium of material that is preferably included in at least the central portion of the device. The filter layer may be constituted of several woven or nonwoven materials, a single or a plurality of layers, with or without an inner or outer cover layer. As mentioned before, the central portion is formed between the demarcation lines extending laterally from the bisecting fold line. Examples of suitable filter material include microfiber fabrics, fibrillated film fabrics, woven or non-woven fabrics (e.g. short or air-laid short fibers), blown fiber fabrics in solution or combinations thereof. Useful fibers for forming such fabrics include, for example, polyolefins such as polypropylene polyethylene, polybutylene, poly (4-methyl-1-pentene) and combinations thereof, halogen-substituted polyolefins such as those containing one or more units of chloroethylene, or tetrafluoroethylene units, and which may also contain acrylonitrile units, polyesters, polycarbonates, polyurethanes, rosin wool, glass, cellulose or combinations thereof. The fibers of the filter layer are selected depending on the type of particulate to be filtered. An appropriate selection of the fibers can also affect the comfort of the respiratory device for the user, for example by providing softness or moisture control. The meltblown microfiber fabrics useful in the present invention can be prepared as described for example, in Wente, Van A., "Superfine Thermoplastic Fibers" in Industrial Engineering Chemistry, Vol. 48, 1342 et seq. (1956) and in report number 4364 of the Naval Research Laboratories, published on May 25, 1954, entitled "Manufacture of Super Fine Organic Fibers" by Van A. Wente et al. The microfibers blown into the filter medium useful for the present invention preferably have an effective fiber diameter of 3 to 30 microns, more preferably from about 7 to about 15 microns, calculated according to the method set forth in Davies, CN, "The Separation of Airborne Dust Particles," Institution of Mechanical Engineers, London, IB Porceedings, 1952. Short fibers may optionally also be present in the filter layer. The presence of short fibers that provide rippled volume provides a more cushioned and less dense fabric compared to a fabric consisting solely of blown microfibers. Preferably, a maximum of 90 weight percent short fibers, preferably a maximum of 70 weight percent are present in the medium. Such fabrics contain short fibers and are described in U.S. Patent No. 4,118,531 (Hauser). Two-component short fibers can also be used in the filter layer, in one or more layers of the filter medium. Short fibers of two components which generally have an outer layer which has a lower melting point compared to the core portion, can be used to form a resilient forming layer joined together at fiber intersection points, for example , by heating the layer so that the outer layer of the two-component fibers flows in contact with adjacent fibers that are two-component fibers or other short fibers. The forming layer can also be prepared with binder fibers of a heat-flowing polyester included together with the short fibers and upon heating of the forming layer the binder fibers melt and flow to the point of intersection of the fibers where they surround to the intersection point of the fiber. By allowing to cool, joints develop at the intersection points of the fibers and keep the mass of the fibers in the desired shape. Further, . binder materials such as acrylic latex or spray-activated heat-activatable adhesive resins can be applied to the fabrics to provide bonding of the fibers. Electrically charged fibers, such as those described in U.S. Patent No. 4,215,682 (Kubik et al.), U.S. Patent No. 4,588,537 (Klasse et al.), Or by other conventional polarization methods or loading electrets, for example by the process of U.S. Patent No. 4,375,718 (Wadsworth et al.), Or U.S. Patent No. 4,592,815 (Nakao) or by a hydrocharging method described in U.S. Patent No. 5,496,507 (Angadjivand et al.) Are particularly useful in the present invention. The fibrillated electrically charged film fibers as described in U.S. Patent No. RE. 31,285 (van Turnhout), they are also useful. Sorbent particulate material (such as activated carbon or alumina) or solvent fibers (for example, activated carbon fibers) may also be included in the filter layer. Such fabrics loaded with particles are described, for example, in U.S. Patent No. 3,971,373 (Braun), U.S. Patent No. 4,100,324 (Anderson) and U.S. Patent No. 4,429,001 (Kolpin et al.). The filter layer masks loaded with particles are particularly good for protection of gaseous materials. As mentioned above, a respiratory device for filtering particulates carried by the air of the present invention must include a filter layer in at least a portion. Preferably, the entire respiratory device according to the present invention includes a filter layer. A personal respiratory device according to the present invention may include at least one optional constituent described herein. For example, the first portion may include a material that provides a moisture barrier to prevent fogging of the user's glasses. Additionally, personal respiratory devices of the present invention are typically held in place on the user's face by constituents well known to those skilled in the art such as strips or bands, preferably as ear loops or tiaras. For example, the loops on the ear can be stapled to the main body of the respiratory device, as shown in Figures 1 and 2, or they can be adhered to the main body or respiratory device by means such as etching, adhesive bonding, ultrasonic welding. , sewing or other means commonly known to those skilled in the art. In accordance with the present invention, a personal respiratory device preferably has a certain degree of adjustability to carry out the attention against the user's face with or without the use of a headband. The strips or bands useful in the present invention may be constructed of thermoplastic elastomers, resilient polyurethane, polyisoprene, butylene-styrene copolymers. One such example is a styrene-butadiene-styrene block copolymer, commercially available under the trade designation KRATON D 1101, from Shell Chemical Co., Houston, TX. The strips or strips may also be constructed of elastic rubber or a covered drawn yarn, such as is commercially available under the trade designation LYCRA, from DuPont Co., Wilmington, DE. Stretch-activated elastomer composites are also useful for strips or webs of the present invention. One such material is a non-adherent multi-layer elastomeric laminate having at least one elastomeric core and at least one relatively non-elastomeric coating layer. The coating layer is stretched beyond its elastic limit and relaxed with the core so as to form a microstructured coating layer. The microstructure means that the surface contains irregularities of peaks and valleys or that it bends which is large enough to be perceived by the human eye as causing increased opacity on the opacity of the composite material before microstructuring, and irregularities which are small enough to be perceived as uniform or soft to human skin. The enlargement of the irregularities is required to see the details of the microstructured texture. Examples of such elastomeric composite materials are described in U.S. Patent No. 5,501,679 (Krueger). Although elastic bands are preferable, non-elastic webs may also be used in the present invention and include, for example, non-woven materials that are formed by wet laying or dry laying processes and consisting of rayon, polyester or similar fibers, fabrics joined by spinning and calendering polypropylene, polyethylene or polyester and reinforced paper. The bands can be tied, held or stretched so that the bands surround the user's head by placing the face mask in sealing engagement with the user's face. The respiratory device may also include an optional exhalation valve, typically a diaphragm valve, which allows for easy exhalation of air by the user. An exhalation valve having an extremely low pressure drop during exhalation for the mask is described in U.S. Patent No. 5,325,892 (Japuntich et al.). Many exhalation valves of other designs are known to those skilled in the art, as well. The exhalation valve is preferably secured in the central portion, preferably near the middle portion of the central portion, by sonic welding, adhesion bonding, mechanical fastening or the like. The respiratory device may optionally be attached at the upper edge or at the outer portions of the respiratory device, such as a facepiece. Typical facial covers are described, for example, in U.S. Patent No. 2,762,368 (Bloomfield) and U.S. Patent No. 4,944,294 (Borek, Jr.). Also useful is the type of facial cover described in U.S. Patent No. 5,020,533 (Hubbard et al.), Which has a cutout approximately in the center of the cover to facilitate adaptation of the respiratory device and cover to the face of the user with a darkened strip on the upper edge of the device to reduce the brightness. In addition, the face seals which minimize air leakage between the device and the face can also be optionally used with the respiratory device of the present invention. Typical face seals are described, for example, in U.S. Patent No. 4,600,002 (Maryyanek et al.), U.S. Patent No. 4,688,566 (Boyce), and U.S. Patent No. 4,827,924 (Japuntich), which describes a ring of soft elastomeric material on the respiratory device 75. In addition, neck covers that protect the neck area, eg, liquid splash, can also be used with the respiratory devices of the present invention. Typical covers for the neck are described, for example, in U.S. Patent No. 4,825,878 (Kuntz et al.), U.S. Patent No. 5,322,061 (Brunson) and U.S. design patent number Des. 347.090 (Brunson). In order to provide comfort and adaptation, any personal respiratory device may include a two-part nose piece. As used herein, the term "two parts" when referring to a nose piece, refers to a configuration wherein a respiratory device of the mask includes a first part for the nose piece on the right side of the respiratory device, and a second piece for the nose on the left side of the respiratory device, wherein the two parts are not joined through the nose when the device is placed by the user. Advantageously, a piece for the nose of two parts decreases the likelihood of forming a similar configuration "peak". In conventional masks a piece for the nose is included as a single part, a separation that points abruptly or a "peak" can be formed on the nose because the only part of the nose piece is bent to accommodate the curvature of the bridge of the nose. The separation or peak is not desirable due to the humidity of the breath that is exhaled by the user, which tends to cloud the user's lenses. Any respiratory device may include a two-part nose piece to improve its fit on the user's nose, for example that which is commercially available under the trademarks 8210MR, 8210iMR, 8246MR, 8247MR, 1860MR, 8110SMR, 8218MR, 8710MR and 2610MR all from Minnesota Mining and Manufacturing Company, St. Paul, MN. Advantageously a piece for the nose of two parts allows the adaptation in the area of the cheek on either side of the nose and at the same time allows a greater adaptation on the bridge of the nose because that portion of the piece for the rigid nose covering the bridge of the nose is missing. Therefore, an improved adaptation to the nose is rved when the respiratory device includes a two-part nose piece. In addition, the manufacture of a respiratory device that includes a two-part nose piece can be simplified. For example, a nose piece can be added from two parts to the respiratory device at any point during the process, which includes before bending the device. In a conventional manufacturing process, a single part of a nose piece is typically added once the device is bent so that the single part for the nose piece resides on both sides of the fold and on the fold itself. Because the nose piece can be added in two parts on either side of the substantially vertical line, the two-part nose piece can be added to a substantially flat preform (described later) at any point in the nose. manufacturing process. For example, the two-part nose piece can be attached to the surface of a cover layer so that the two-part nose piece is included within the device (so that the nose piece is invisible to the nose). the user) or on an outer surface of the device. A nose piece useful in the respiratory device of the present invention may include a single part nose piece or a two piece nose piece. In any embodiment, the nose piece can be made of a conformable material, for example, a soft dead flexible band of metal such as aluminum or wire coated with plastic and can be shaped or adapted to the ability of the device to adapt to the face of the user. Additionally, a non-linear nose piece configured to be supported on the bridge of the nose of the user having inflections positioned around the clasp section to provide fins that help provide a firm placement of the mask in the nose and area of the nose. the cheekbones The nose piece can be secured to the respiratory device by an adhesive, for example, a pressure sensitive adhesive, a liquid hot melt adhesive or ultrasonic welding. Alternatively, the nose piece may be enclosed in the body of the respiratory device or may be maintained between the body of the device and a fabric or foam that is mechanically or adhesively bonded thereto. In one embodiment of the invention such as that shown in Figure 2, the nose piece is placed on the outside of the nose portion. Because the portion of the nose is more flexible than the central portion, a respiratory device according to the present invention preferably does not require the presence of a piece of foam. If it is included, a piece of foam is typically placed between a respiratory device in alignment with the nose piece to add comfort to the user. The personal respiratory devices of the present invention can be sterilized by any standard method, such as gamma radiation, exposure to ethylene oxide or autoclaving. A flat bent respiratory device, such as that illustrated in Fig. 1, is preferably formed as a single piece, although multiple pieces can be joined together using the various techniques described herein, such as batch processes (e.g. plunger) or a continuous process (for example, rotating welding). In any process, preferably a flat bent respiratory device is produced by forming a substantially planar sheet of a multilayer construction (also referred to herein as a "preform") by joining and cutting the forming edges. Other techniques can be used to form the edges, using other techniques such as ultrasonic welding, sewing and the application of pressure to form the edges (with or without the addition of heat). In accordance with the present invention, a substantially planar preform can have any shape. As shown in Figure 3, the substantially flat preform 136 has a diamond shape, although other shapes (eg pentagonal, hexagonal, semi-circular, square, butterfly-shaped, etc.) are equally suitable. A process according to the present invention also includes forming at least one demarcation line within the preform; folding the preform along a substantially bisecting axis; and form a first angle and a second angle. Figure 3 is a schematic illustration of a production process 120 for manufacturing flat bent respiratory devices, as shown in Figure 1. An inner cover fabric 124 and a filter layer 126 are preferably provided in roll form for a process substantially continuous. In an alternative embodiment, the nose piece 24 (eg, as a two-part nose piece described above) can be placed on the outside of an inner surface of either the inner cover fabric 124 or the fabric 132 of outer cover. A reinforcing material 128 is preferably positioned close to the center of the filter layer 126. The filter layer 126 and the reinforcement material 128 are covered by an outer cover fabric 132 to form a cloth assembly 134. The cloth assembly 134 can be held together by surface forces, electrostatic forces, thermal bonding, an adhesive or any other suitable well-known means. As illustrated in Figure 3, the cloth assembly 134 can be welded and cut to form a preform 136 in the welding station 136a. Preferably, the preform 136 is substantially flat so that the face mask according to the present invention can be formed at relatively high speeds and at a relatively low cost because conventional components, such as molded backing covers, are not required . In addition, the preform 136 then passes through a demarcation station 138. In the demarcation station 138, at least one demarcation line is formed in the preform to form a demarcated preform 136 '. A demarcation line can be formed by various techniques including ultrasonic welding, application of pressure (with or without the presence of heat), sewing, application of sticks and the like. As shown in Figure 4a, the demarcated preform 136 includes demarcation lines A, A ', B and BA. As discussed in the foregoing, the demarcation lines work to prevent delamination of the layers to the preform, to add reinforcement or rigidity to the second portion of the facial mask during use and to provide greater flexibility of the first portion and the third portion relative to the second portion. Figure 5, taken through line 5-5 in Figure 4a, illustrates a cross section of a welded preform 136 '. The second portion 38 preferably includes an outer layer 132, a layer 128 of reinforcing material, a filter layer 126 and an inner layer 124. The first portion 34 and the third portion 36 preferably include the outer layer 132, the filter layer 126 and an inner layer 124. As mentioned above, the reinforcing material 128 is preferably absent from each of the first portion 34 and the third portion 26. As shown in Figure 5, a slight extension of the reinforcement material 128 may be necessary in the first portion. , the third portion or both so that all the layers can be joined via the demarcation lines. Alternatively, the reinforcing material 128 may extend into the demarcation lines but not further, or may extend just inside the demarcation lines so that the reinforcement material is located within a receptacle formed by the lines of demarcation. demarcation. Referring now to Figure 4b, the pre-shaped preform 136 'is preferably folded along the bisecting fold 18 parallel to a substantially vertical axis along the mid-section of the length of the welded preform 136'. As shown in Figure 4c, a preform 136"folded" is then welded and cut along the lines C and D, each at predetermined angles relative to the second bending line 14 ', to form lines 14 and 14"of bending, respectively. As mentioned in the above, the preform 136 'demarcated preferably is formed from a single piece. However, multiple pieces can be joined along the fold lines 14, 14 'and 14", so that any or all of these fold lines include a weld line, Preferably, the fold line 14'. does not include a welding line.

Each of the predetermined angles of lines C and D may vary, independently to adjust the size and shape of the resulting face mask by adjusting the first portion or the third portion, or both. For example, the bent preform can be welded and cut along the line C so that the bending line 14 is provided at an angle of approximately 147 ° relative to the second bending line 14 'to form a portion of nose. Similarly, the bent preform can be welded and cut along the line D so that the third bending line 14"is provided at an angle of about 142 ° relative to the second bending line 14 'to form the bend. third portion As mentioned above, these angles can easily vary to adapt to different sizes and shapes of the face A process according to the present invention is preferably capable of high speed production methods and can comprise additional steps as needed for attachment of headbands, nose pieces and other components typical of a respiratory device The personal respiratory protection devices of the present invention are further described by means of the non-limiting examples set forth below. Each of the examples uses an ultrasonic welding unit that are commercially available under the commercial designation of model 1300 P of Branson Ultrasonics Corporation, Danbury, CT. For each of the welding operations in the following examples, the settings of the welding unit are set as follows.

Parameter Value Power output 90-100% Welding time 1.5 seconds * Holding time 2.5 seconds Welding pressure 620 kPa (90 psi) * The holding time refers to the period of time during which the preform is held under pressure in the absence of ultrasonic energy In each of the examples, the individual materials that form the layers are assembled in the following order: 1. Outer cover fabric 2. Reinforcement 3. Filter material 4. Inner cover fabric The materials are laminated together and then welded together using an anvil 60, as shown in Figure 6, where the weld projections 62, 62 ', 64 and 64' pressed into the stratified material to form the demarcation lines A, A ', B and B1, respectively, as illustrated in Figure 4a. Then, the diamond shaped preform is formed using an anvil 70 which is illustrated in Figure 7. The anvil 70 is first pressed into stratified material that includes the demarcation lines, resulting in the left half of the welded preform . Then, the anvil 70 rotates 180 ° and presses into the laminated material so that the first compression described above and this second compression complete the formation of the welded preform as illustrated in Figure 4a. A bent preform is made, and welded along lines C and D, as shown in Figure 4c. Each of the examples below contains a filter material which is a layer of electrically charged melt blown polypropylene microfibers with a fiber diameter of about 7 to about 8 microns and a basis weight of about 50 grams per square meter. Additionally, each of the examples below includes a nose piece, either as a single part or as a two-part nose piece. Each of the nose pieces is formed from an inactive soft aluminum band having a width of approximately 5 mm and a thickness of approximately 0.8 mm. For a single part nose piece, the length is approximately 87 mm. For a part for the nose of two parts, the length of each part is approximately 38 mm.

Example 1 A personal respiratory device that includes loops for the ears Item Description of the supplier Matepal supplier Cover fabric Daltex 1 -50-B 1 -U00 Don and Low Polypropylene joined by outside Nonwovens, Forfar. yarn, 50 grams per Scotland. United Kingdom square meter Reinforcement Colprop PXP75 Akzo Nobel Polypropylene bonded by Nonwovens, Amhem yarn, 75 grams per Netherlands square meter Cover fabric Daltex LS 1043 Don and Low Polypropylene joined by interior Nonwovens. Forfar. yarn. 20 grams by Scotland, United Kingdom Square meter Ear loops Formed from Kraton D 1 101 (Shell, Houston, TX) having the dimensions of 4.8 mm wide. 220 mm long, 1 mm thick (2 of each) Staples STH5019 The Stanley Bostitch East Steel Greenwich. Rl Example 2 A personal respiratory device that includes adjustable loops for the ears.

Item Supplier Description Material supplier Cover fabric Daltex 1 -50-B 1 -U00 Don and Low Polypropylene joined by outside Nonwovens, Forfar, yarn, 50 grams by Scotland. United Kingdom square meter Reinforcement Colprop PXP75 Akzo Nobel Polypropylene joined by Nonwovens. Amhem yarn, 75 grams per Netherlands square meter Cover fabric Daltex LS 1043 Don and Low Polypropylene bonded by interior Nonwovens, Forfar, yarn, 20 grams by Scotland. United Kingdom square meter Ties for the ears Formed by polyisoprene, which have the dimensions of 4.8 mm wide, 22 cm long, 0 5 mm thick (2 of each) Staples STH5019 VA Stanley Bostitch East Steel Greenwich. Rl Staples Standard staples Stanley Bostitch East Steel Greenwich. Rl Example 3 A personal respiratory device that includes a reticulate as a reinforcement.

Item Supplier Description Material supplier Cover fabric Naltex Plastics, Inc. Filtering Reticulated Lightweight Extruded External Bonding 37-4057 Austin TX Polypropylene Reinforcement Colprop PXP75 Akzo Nobel Polypropylene bonded by Nonwovens, Amhem yarn, 75 grams per Netherlands square meter Cover fabric Daltex LS 1043 Don and Low Polypropylene joined by interior Nonwovens. Forfar. yarn, 20 grams per Scotland, United Kingdom square meter Ties for the ears As in example 1 Staples STH5019 V * Stanley Bostitch East Steel Greenwich, Rl Example 4 A personal breathing device without a reinforcing layer and including a braided headband.

Item Supplier Description Material supplier Cover fabric Daltex 1 -50-B 1 -U00 Don and Low Polypropylene joined by outside Nonwovens, Forfar, yarn, 50 grams by Scotland, United Kingdom square meter Cover fabric Daltex LS 1043 Don and Low Polypropylene bonded by interior Nonwovens, Forfar, yarn. 20 grams for Scotland, United Kingdom square meter Headband G-9- 10- 1 Providence Braid Co., Polypropylene- Pawtucket, Rl polyisoprene 4.8 mm x 343 mm x 1 mm (2 of each) Staples STH5019 V, Stanley Bostitch East Steel Greenwich, Rl Example 5 A personal respiratory device is designed that includes a two-part nose piece and braided 5 loops for the ears.

Item Supplier Description Material supplier Cover fabric Daltex 1 -50-B 1 -U00 Don and Low Polypropylene joined by outside Nonwovens, Forfar, yarn, 50 grams for Scotland, United Kingdom square meter Reinforcement Colprop PXP75 Akzo Nobel Polypropylene bonded by Nonwovens, Amhem yarn, 75 grams per Netherlands square meter Cover fabric Daltex LS 1043 Don and Low Polypropylene joined by interior Nonwovens, Forfar. yarn, 20 grams per Scotland. United Kingdom square meter aH? aAriua? ^ Ear loops G-9- 10- 1 Providence Braid Co. Polypropylene Pavvtucket, Rl polyisoprene, which have the dimensions of 4.8 mm wide, 22 cm long, 0.5 mm thick (2 of each a) Staples STH5019 VA Stanley Bostitch East Steel Greenwich, Rl Each of the personal respiratory devices in the previous examples show good fit and features away from the face. It is surprising how well adapted personal respiratory devices are, which can be easily fabricated from a substantially flat multiple layer piece, only. Personal respiratory devices of the present invention include, for example, respirators, surgical masks, cleaning room masks, facial covers, dust masks, masks for heating the breath and a variety of other face covers. The respiratory devices of the present invention provide improved sealing engagement to the wearer's face as compared to some other conventional types of flat folded face masks. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (19)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A personal respiratory protection device, characterized in that it comprises: a non-folded main body, comprising: a first portion; a second portion differentiated from the first portion by a first line of demarcation; a third portion differentiated from the second portion by a second line of demarcation; and a substantially vertical bisecting fold extending through the first portion, the second portion and the third portion; wherein the device is capable of being bent into a first substantially flat bent configuration along the bisecting fold and is capable of being unfolded or unfolded to an open convex configuration.

2. The device according to claim 1, characterized in that the device includes a filter means.

3. The device according to claim 2, characterized in that the device includes a cover layer.

4. The device according to claim 3, characterized in that the device includes a reinforcing layer.

5. The device according to claim 4, characterized in that the first portion and the third portion are substantially free of the reinforcing layer.

6. The device according to claim 4, characterized in that the first demarcation line includes a welding line extending substantially coextensive therewith and wherein the welding line joins the first filter layer, the cover layer and the layer of reinforcement boards.

7. The device according to claim 6, characterized in that the second demarcation line includes a welding line extending substantially coextensive therewith, wherein the welding line joins the filter layer, the cover layer and the coating layer. reinforcement joints.

8. The device according to claim 1, characterized in that the main body comprises a piece.

9. A process for producing respiratory devices, characterized in that it comprises folding a preformed blank onto a bisecting shaft to create a preform having a bisecting bend line and cutting the preform at a first desired angle in a first position in relation to the line of bisecting fold, wherein the first desired angle depends on the desired size of the device.

10. The process according to claim 9, characterized in that it comprises the additional step of cutting the preform at a second desired angle in a second position in relation to the bisecting fold line, wherein the second desired angle depends on the desired size of the device.

11. The process according to claim 9, characterized in that it comprises the additional step of forming a first and second demarcation lines in the preform.

12. A personal respiratory protection device, characterized in that it comprises: a non-folded main body, comprising: a first portion, a second portion differentiated from the first portion by a first demarcation line; a third portion differentiated from the second portion by a second line of demarcation; and a bisecting fold extending through the first portion, the second portion and the third portion, - wherein the demarcation lines extend laterally from the bisecting fold and the device is capable of bending to a first substantially flat bent configuration along the bisecting fold and is capable of unfolding or unfolding to an open convex configuration.

13. A personal respiratory protection device, characterized in that it comprises: an unfolded main body, comprising: a first portion, - a second portion differentiated from the first portion by a first demarcation line; a third portion differentiated from the second portion by a second line of demarcation; and a bisecting fold extending through the first portion, the second portion and the third portion; wherein the demarcation lines do not intersect and the device is capable of bending to a first substantially flat bent configuration along the 10 bisecting fold and is capable of being unfolded to an open convex configuration.

14. The device according to claims 1 to 8, 12 or 13, characterized in that in addition 15 of the bisecting fold, other fold lines are not necessary to obtain a substantially flat bent configuration of the device.

15. The device according to claims 1 to 8 or 12 to 14, characterized in that the second portion is formed between the demarcation lines.

16. The device according to claims 1 to 8 or 12 to 15, characterized in that the rtüfaridta ^ demarcation lines improve the flexibility and adaptation of the device around the nose and cheeks of the user.

17. The device according to claims 1 to 8 or 12 to 16, characterized in that the demarcation lines add rigidity to the second portion of the device.

18. The device according to claims 1 to 8 or 12 to 17, characterized in that the demarcation lines provide greater flexibility of the first portion and the third portion in relation to the second portion.

19. The device according to claim 3 or 4, characterized in that the demarcation lines prevent delamination of the layers.