Surgical face mask

BACKGROUND

This invention relates to face masks, and, more particularly, to a disposable face mask particularly suitable for use by surgeons, nurses and the like.

Hospitals are becoming increasingly aware of the economy and safety of disposable surgical apparel. The disposability of these items eliminates the somewhat costly sterilizing procedures that they must undergo after each use, and also eliminates the possibility of infection and cross-contamination if the items are not completely sterilized before the next use. Problems have arisen, however, in providing disposable surgical face masks. Such masks may be worn for periods of up to several hours during operations, and must therefore be both durable and comfortable for the wearer. Materials which are found to be comfortable and nonirritating to the wearer’s face, and which are inexpensive enough to allow disposability after a single use, tend to lack the durability and strength necessary to withstand an extended period of use. It is apparent that even partial disintegration or partial loss of effectiveness Of such a mask during surgery may have serious consequences for both the wearer and the patient.

SUMMARY

One aspect of the invention lies in the discovery that if a thin sheet of nonrigid open-celled plastic foam forms the innerlayer of a face mask which has intermediate and outer layers of conventional filtering material and nonwoven material, then such foam will maintain the physical integrity ofthe mask for extended periods of wear and will result in a mask which readily conforms to the face of the wearer and provides a comfortable fit. Such mask is relatively inexpensive to manufacture and is intended to be discarded after a single use. Other advantages and objects of the invention will become apparent as the specification proceeds.

DESCRIPTION OF THE DRAWING

The invention will be explained in conjunction with an illustrative embodiment shown in the accompanying drawing, in which:

FIG. 1 is a perspective view showing a person wearing a mask formed in accordance with the invention;

FIG. 2 is a front elevational view of the mask;

FIG. 3 is a sectional view taken along the line 3—3 of FIG 2;

FIG. 4 is a rear elevational view, partially broken away, of the mask;

FIG. S is a sectional view taken along the line 5—S of FIG. 2; and

FIG. 6 is an enlarged fragmentary view showing the various layers of the mask.

DESCRIPTION OF SPECIFIC EMBODIMENT

Referring to FIG. 1, the numeral 10 designates generally a g() surgical face mask being worn by a surgeon S. The mask is seen to cover the nose, mouth and chin of the wearer, and is secured to the face by means of tie strips 11 and 12.

Referring now to the other figures the mask is seen to have an elongated, rectangular shape provided by a mask panel 13 and orthogonally arranged border strips 14, 15, 16 and 17. The mask panel 13 includes a folded or pleated central portion 18 provided by reverse folds 19, 20, 21, and 22 (FIG. 3), and the ends of the pleat are secured by side border strips 15 and 16.

Referring to FIG. 6, which is an enlargement of the circled portion 6 of FIG. 3, the panel 13 is seen to include an inner layer 23 adapted to be positioned adjacent the face of the wearer, an intermediate layer 24, and an outer layer 25. The inner layer 23 which is worn against the face is formed of an open pore polymeric foam material such as polyurethane foam to provide a soft and comforting surface. THe middle layer 24 is formed of a standard filter medium such as matted glass fibers or other conventional filtering materials, and the outer layer 25 is formed of a nonwoven material which is similar in softness and drape to cloth but lower in cost and which is better suited to prevent the passage of airborne bacteria. Soft porous paper has been found particularly suitable for such outer layer.

’ The three layers 23-25 are all generally rectangular and coextensive, and after the longitudinally extending center pleat 18 is formed by folding the three layers, the outer edges of the layers are secured by the border strips 14-17. As can be . seen best in FIG. 3, the border strips, which may also be formed of nonwoven cellulosic material, are folded about the edges of panel 13. The border strips may be secured to the periphery of the panel by gluing or by providing a polyethylene coating on the inner surface of the strips and , then heat sealing the strips to the panel.

The tie strips 11 and 12 may be formed as continuous extensions of the top and bottom border strips 14 and 16, respectively, and are of a length suitable to permit typing at the back of the head of the wearer. Referring to FIG. 5, the tie strips may be strengthened by a string 26 which may extend for the entire length of the tie strips and the associated border strip. The string 26 is seen to be secured by folding the tie strip 12 and its inner polyethylene coating 27 about the string and then heat sealing the polyethylene-coated surfaces.

A bendable or deformable strip 28 of soft metal is adhesively secured to the outer side of the top border strip 14 and may be bent about the nose of the wearer to conform the face mask to the individual facial features of the wearer.

The mask is worn by pulling the top and bottom portions of the mask panel 13 to unfold the pleated central portion of the mask panel and positioning the top border strip 14 about the nose of the wearer and the bottom border strip 16 below the chin of the wearer. The pleated central portion 18 provides ample room for the wearer’s nose, mouth and chin, and when the mask is positioned on the wearer’s face, the mask will unfold automatically to adapt to each wearer’s individual facial differences. As can be seen in FIG. 1, the side edges of the folded mask panel 13 are secured by the side border strips 15 and 16, but the pleated portion 18 will unfold intermediate the side border strips to cover the nose and chin. The nose clip 28 is then bent to conform closely to the contour of the wearer’s nose, and the tie strings 11 and 12 may be secured at the back of the head.

The soft inner foam layer 23 readily conforms to the face of the wearer and possesses breathability which permits fluids such as perspiration, saliva, and the moisture of exhaled air to be transmitted to the intermediate layer 24 and, at least in some instances to the outer layer 25. The effect is a preferential absorption and retention of fluids by layers other than the layer in contact with the wearer’s face. Furthermore, since durability and strength of the plastic foam are not affected by the transmitted moisture, the mask retains its form and integrity even though the intermediate and outer layers become moistened. The result is a mask having an inner layer which imparts a soft, dry, and comfortable feeling to the wearer’s face even after an extended wearing period and, even more important, a mask which remains intact to block particles and airborne bacteria even after the mask has collected or absorbed moisture.

I have found that the inner foam layer makes the face mask at least as durable as a conventional nondisposable mask. The foam layer is resistant to tearing and abrasion and it is not rendered useless by such things as beards, prolonged use, moisture, or orthodontic braces which might otherwise cause stretching, tearing, or abrasion. However, even though the mask is durable, it is relatively inexpensive and can economically be disposed of after a single use.

While in the foregoing specification I have described an embodiment of my invention in considerable detail for the pur3,603,315 pose of illustration, it is to be understood that many of the details herein given may be varied considerably by those skilled in the art without departing from the spirit and scope of my invention.