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

#The present invention relates to respirators or face masks which are capable of being folded flat during storage and forming a cup-shaped air chamber over the mouth and nose of a wearer during use.

#Filtration respirators or face masks are used in a wide variety of applications when it is desired to protect a human's respiratory system from particles suspended in the air or from unpleasant or noxious gases. Generally such respirators or face masks are of one of two types—a molded cup-shaped form or a flat-folded form. The flat-folded form has advantages in that it can be carried in a wearer's pocket until needed and re-folded flat to keep the inside clean between wearings.

#The flat-folded form of face mask has been constructed as a fabric which is rectangular in form and has pleats running generally parallel to the mouth of the wearer. Such constructions may have a stiffening element to hold the face mask away from contact with the wearer's face. Stiffening has also been provided by fusing a pleat across the width of the face mask in a laminated structure or by providing a seam across the width of the face mask.

#FIG. 1 is a front view of a personal respiratory protection device of the invention in flat-fold configuration.

#FIG. 2 is a cross-section taken along line 2—2 of the personal respiratory protection device shown in FIG. 1.

#FIG. 3 is front view of the personal respiratory protection device of FIG. 1 shown in open ready-to-use configuration.

#In one embodiment of the invention as shown in FIG. 1, a front view of personal respiratory protection device 10, the device has a generally rectangular shape when in the folded form for storage in a package prior to use or in a wearer's pocket. A side view of personal respiratory protection device 10, shown in FIG. 2, shows the device having a central portion 12, a first member 14 and second member 16. The central portion and the first and second members are joined, for example, as shown in FIG. 2 by folds 15 and 17, or the first and second members may be bonded or seamed to the central portion. The configuration is held in place by edge seals 11 and 11′ which may extend from fold 15 to fold 17 as shown or they may extend partially from fold 15 to fold 17. Edge seals 11 and 11′ may be substantially straight as shown or they may be curved. FIGS. 1 and 3 also show attachment means 18, 18′ for attaching, for example, a head band to hold the device in place on a wearer's face. When the device is a multilayer construction, having, for example, filter media layer(s), an optional cover layer, and an optional stiffening layer, the perimeter edges of first and second members 14 and 16 are also bonded.

#The personal respiratory protection device 10 is shown in FIGS. 3, and 4, where common parts are identified as in FIGS. 1 and 2, in its opened, ready-to wear configuration having the general shape of a cup or pouch which provides the wearer with the “off-the-face” benefits of a molded cup-shaped respiratory device. The cup-shaped “off-the-face” design of the respiratory device of the invention provides a periphery region formed by edges 24 and 26 of the first and second members, respectively, for sealing the respiratory device against the face of the wearer. FIG. 3 shows personal respiratory protection device 10 with optional nose clip 28. To allow the wearer a greater degree of jaw movement, a generally widthwise fold, or pleat, can be formed in first member 14 or second member 16 of the respiratory device, just above the fold or bond 15 or just below the fold or bond 17.

#In another embodiment shown in FIGS. 5 and 6, where common parts are identified as in FIGS. 1–4, additional members 20 and 22 are attached to the first and second members 14 and 16 of respiratory device 10′ by folds 21 and 23 or by bonding or seaming (not shown). Additional members 20 and 22 may be sealed with central portion 12 and first and second members 14 and 16 at edge seals 11, 11′, but preferably are not sealed at the edge seals as shown in FIGS. 5 and 6 to provide enhanced sealing at the periphery of respiratory device 10′ due to the ability of the additional portions 20 and 22 to pivot at the attachment points 25 and 25′. FIG. 6 shows respiratory device 10′ with optional nose clip 28 located on additional member 20. In this embodiment, when multiple layers are used to form the respiratory device, perimeter edges of additional members 20 and 22 are also preferably bonded.