JP2022115632A - Sheet for sanitary mask - Google Patents

Abstract

To provide a sheet for a sanitary mask, in which cut cross-sections of stacked sheets hardly stick to each other when cut out into the mask shape, and can be easily peeled off even if they partly stick to each other.SOLUTION: A sheet for a sanitary mask is formed by using such a sheet as an end portion curls up in a natural state.SELECTED DRAWING: Figure 1

Description

The present invention relates to a sanitary mask sheet.

A sanitary mask is used for the purpose of covering the mouth and nose of a person and preventing intrusion of airborne particles (for example, dust, dust, pollen, viruses, droplets containing viruses, etc.) from the outside. The purpose of using the sanitary mask also includes preventing droplets containing viruses from diffusing to the outside through the mouth and nose.
Various techniques have been proposed so far for such sanitary masks.
For example, Patent Literature 1 has a substrate that covers the nostrils, and pleats are arranged on both the face contact surface substrate and the front surface substrate of the substrate.

JP 2014-212798 A

A sanitary mask, especially one that can be folded in a substantially bilaterally symmetrical manner and is worn with the fold unfolded during use, is manufactured by folding one raw fabric sheet into two layers or by stacking two raw fabric sheets. This is done by cutting out the shape of a sanitary mask. For example, a sanitary mask is manufactured by integrally cutting out a mask body that covers a person's face and an ear hook that fixes the wearing state of the mask body.
In this case, the fibers are entangled with each other at the cut cross section of the outer edge of the overlapping sanitary mask, or are fused together due to friction during cutting. Therefore, the left and right mask body portions and the ear hook portions of the sanitary mask are stuck to each other in the cut cross section, and it may not be possible to separate them and open them naturally.
The sanitary mask described in Patent Document 1 does not describe a means for eliminating entanglement or fusion between fibers in the cut cross section.

In view of the above points, the present invention relates to a sanitary mask sheet that does not easily stick to the cut cross section when cut out along the shape of the mask, and that even if part of the sheet sticks, it can be peeled off naturally.

The present invention provides a sanitary mask sheet whose edges are curled in a natural state.

Even when the sanitary mask sheet of the present invention is cut out along the shape of the mask, the cut cross section does not stick easily, and even if part of the sheet sticks, it can be peeled off naturally.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows an example of preferable embodiment of the sheet|seat for sanitary masks which concerns on this invention. FIG. 2 is a partial perspective view showing an example of a layered structure of sanitary mask sheets according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing an example of a preferred embodiment of a method for manufacturing a sanitary mask using a sanitary mask sheet according to the present invention, where (A) is an explanatory diagram showing a step of forming a joint portion, and (B) is It is explanatory drawing which shows the process which cuts out the outer shape of a sanitary mask, and (C) is explanatory drawing which shows the obtained sanitary mask. FIG. 2 is a cross-sectional view showing an example in which the sanitary mask sheet shown in FIG. 1 is a sheet obtained by laminating a relatively highly stretchable sheet and a relatively less stretchable sheet. FIG. 5 is a partially cutaway perspective view schematically showing an example of a preferred embodiment of a relatively highly stretchable sheet included in the sanitary mask sheet shown in FIG. 4 . (A) In the sanitary mask sheet shown in FIG. 4 , FIG. 5 is a partial perspective view showing an example in which the sheet for a sanitary mask shown in FIG. It is explanatory drawing which shows typically the warped state. Fig. 6(A) is a perspective view showing a rolled-up state of an end portion of the sanitary mask sheet shown in Fig. 6(A) . (A) to (C) are explanatory diagrams showing an example of a preferred embodiment of the method for manufacturing the sanitary mask sheet shown in FIG. Fig. 8 is a partially enlarged cross-sectional view showing an example of a preferred embodiment of the layered structure of the sanitary mask sheets shown in Fig. 7; (A) and (B) are explanatory diagrams showing a method of measuring the ratio of the surface area of the uneven sheet per unit area in plan view of the sanitary mask sheet. 8 is a perspective view showing an example of a sanitary mask manufactured using the sanitary mask sheet shown in FIG. 7. FIG. FIG. 11 is an explanatory diagram schematically showing a state in which the ear hook portion of the sanitary mask is put on the user's ear when the sanitary mask shown in FIG. 10 is in use. 1 is a perspective view showing a state in which a filter sheet provided with the sanitary mask sheet of the present invention is attached to a sanitary mask. FIG. 1 is a drawing-substituting photograph showing a cut surface of a sanitary mask produced using a sanitary mask sheet sample of an example. 3 is a drawing-substituting photograph showing a cut surface of a sanitary mask produced using the sanitary mask sheet sample of Comparative Example 1. FIG. 3 is a drawing-substituting photograph showing a cut surface of a sanitary mask produced using the sanitary mask sheet sample of Comparative Example 2. FIG.

A preferred embodiment of the sanitary mask sheet according to the present invention will be described below with reference to the drawings.
As used herein, the term “sanitary mask” refers to a mask that is worn on a person's face for breathing, filters air before inhaling it into the human respiratory tract, and exhales droplets before exhaling to the outside. It refers to the article to be filtered. Therefore, the sanitary mask sheet according to the present invention preferably has a size and shape sufficient to cover at least a person's mouth and nose.

As shown in FIG. 1, the sanitary mask sheet 10 (hereinafter also simply referred to as the sheet 10) of the present embodiment has an edge 11 curled in a natural state. The term "ends" as used herein refers to the ends 11 and 12 in the longitudinal direction and the transverse direction of the sheet 10. Considering the process of continuously forming the sanitary mask, at least the sheet 10 is It is preferable that the ends 11 in the longitudinal direction X are curled. Further, "curled in a natural state" means that when the sheet 10 is left standing on a flat surface with one surface 1S facing downward and the opposite surface 1R facing upward as shown in the figure, the edges of the sheet 10 are curled. It means that the part is warped toward the opposite surface 1R side. More specifically, the sanitary mask sheet 10 is placed on a flat surface, and an external force is applied to bring the entire surface of the sanitary mask sheet into close contact with the flat surface. After that, when the external force is removed, a state in which a part of the sanitary mask sheet rises from the flat surface is called "curling".

In the example of FIG. 1, the end 11 in the longitudinal direction X of the end 11 in the longitudinal direction X of the sheet 10 and the end 12 in the transverse direction Y orthogonal thereto is turned up as described above. In the natural state, the end portion 11 in the longitudinal direction X has one surface 1S warped toward the opposite surface 1R side, preferably warped in a direction opposite to the extending direction of the sheet 10, and curled one round or more. Turn 13. Further, it is more preferable that the winding portion 13 is in contact with the opposite surface 1R of the sheet 10 in the natural state.
It should be noted that the turning direction is not limited to the side of the opposite surface 1R, and may be the side of the one surface 1S.

Since the sanitary mask sheet 10 of the present embodiment has such a strong property that it can be rolled up, the entire sheet has the property of being naturally deformed into an arc shape. Therefore, even in the sanitary mask cut out from the sheet 10, a force acts on the cut cross section of the outer edge of the sanitary mask to turn it over. That is, the cut cross section is made to be naturally rolled up. This makes it difficult for the cut cross-section to stick together, and even if a portion of the cut section sticks, it can be peeled off naturally. The cut cross section of the sanitary mask will be described later.

The sanitary mask sheet 10 of the present embodiment is a material for manufacturing a sanitary mask, for example, as shown in FIG. It is brought into a state of having an overlapping structure 50 .
At this time, as shown in the drawing, the end portions of the sanitary mask sheet 10 are preferably rolled up toward the exposed surfaces 5S and 5R, which are the outer side of the layered structure 50 (opposite side to the inner side). That is, in a natural state in which the layered structure 50 is placed on a flat surface, the sheet upper layer 14 and the sheet lower layer 15 constituting the sanitary mask sheet 10 are arranged so that curling of the ends occurs in opposite directions. is preferred. More specifically, preferably, the end portion 14A of the sheet upper layer 14 is formed with the wound portion 13 on the side of the opposite surface 1R of the sheet upper layer 14, that is, on the upper exposed surface 5S of the overlapping structure 50. As shown in FIG. At the same time, preferably, the end portion 15A of the sheet lower layer 15 is formed with the winding portion 13 on the side of the opposite surface 1R of the sheet lower layer 15, ie, on the lower exposed surface 5R of the lap structure 50. As shown in FIG. In this way, it is preferable that the sheet upper layer 14 and the sheet lower layer 15 are turned up in opposite directions at their ends.
As a result, the layered structure 50 of the sanitary mask sheet 10 is placed in a state where the sheet layers repel each other before the cutout, and the force to turn over the cut cross section after the cutout tends to work more remarkably.
When the layered structure 50 is formed by stacking two sanitary mask sheets 10, it is preferable that not only one end in the longitudinal direction X but also the other end be similarly curled. Moreover, it is preferable that the overlapping structure 50 has a curling force acting not only in the longitudinal direction X but also in the lateral direction Y, so that curling of the ends is similarly generated. In addition, the direction in which the end portion 14A of the sheet upper layer 14 and the end portion 15A of the sheet lower layer 15 are turned may not be the direction shown in FIG. For example, one end may be turned outward and the other end may be turned inward. From the viewpoint of good performance of the manufacturing method described below, it is preferable that at least one end of the upper sheet layer 14 and the lower sheet layer 15 is turned outward (that is, the exposed surface side of the layered structure 50). In particular, the upper sheet layer 14 and the lower sheet layer 15 are folded at their respective ends in opposite directions (that is, toward the exposed surfaces 5S and 5R on both upper and lower surfaces of the layered structure 50) as shown in FIG. preferable.

Using such a layered structure 50 of the sanitary mask sheet 10, a sanitary mask 500 can be manufactured by the steps shown in FIGS. 3(A) to 3(C), for example. The sanitary mask 500 thus manufactured is an integral type with no seam between the mask main body 501 and the ear hook 502, and can be folded symmetrically. 3(A) to 3(C) omit curling at the edge of the sheet 10, but actually the sheet 10 is curled as shown in FIG. In FIGS. 3A to 3C, the sheet upper layer 14 and the sheet lower layer 15 are shown with a slight separation so that the layered structure 50 of the sheet 10 can be recognized, but they are actually laminated without separation.
First, as shown in FIG. 3(A), a joint portion 5M of a sanitary mask is formed on the layered structure 50. Then, as shown in FIG. The joint portion 5M is located at the center of the mask main body of the sanitary mask to be manufactured, and corresponds to the portion where the sanitary mask contacts the region connecting the nose, mouth and chin of the wearer. In the step shown in FIG. 3(A), it is preferable that the joint portion 5M is formed in an arc shape in a direction toward the lateral direction Y of the layered structure 50 of the sheet 10. As shown in FIG.
Next, as shown in FIG. 3B, the outer shapes of the mask main body 501 and the ear hooks 502 are cut out rearward in the longitudinal direction X from the joint 5M. At that time, the ear hooking portion 502 is further provided with an opening portion 512 through which the ear is passed. Thus, the sanitary mask 500 shown in FIG. 3(C) is manufactured.
The manufactured sanitary mask 500 is strongly affected by the turning-up force of the sanitary mask sheet 10 of the present embodiment. , curling occurs in the same manner as described above. Further, similar curling occurs at the edge 512A of the outer edge of the opening 512 of the ear hooking portion 502 as well. As a result, as described above, the cut cross section, which is the end of each part of the sanitary mask 500, is less likely to stick, and even if a part sticks, it can be peeled off naturally.
As a result, the sanitary mask 500 manufactured using the sanitary mask sheet 10 of the present embodiment has an edge portion 501A along the outer shape of the mask main body portion 501, an edge portion 502A along the outer shape of the ear hook portion 502, and an ear hook portion 502A. The end portion 512A of the outer edge of the opening portion 512 of the hook portion 502 is easy to grasp and can be opened smoothly without delay during use.

The sanitary mask sheet 10, which exerts such a strong peeling force, has a fiber network structure in consideration of the feel of the sanitary mask and the ability to capture fine particles in the air inherent to the sanitary mask. or a perforated sheet using a polyurethane material, or a combination thereof.
As the fiber sheet, various materials that are commonly used in sanitary masks can be used, such as a nonwoven fabric sheet.
As the nonwoven fabric sheet, various types can be used as long as the aforementioned characteristics of the sanitary mask sheet 10 of the present embodiment are not impaired. For example, nonwoven fabrics obtained by the meltblown method (meltblown nonwoven fabrics), nonwoven fabrics obtained by the electrospinning method (electrospinning nonwoven fabrics), nonwoven fabrics obtained by the spunbond method (spunbond nonwoven fabrics), nonwoven fabrics manufactured by the air-through method ( air-through nonwoven fabric), nonwoven fabric manufactured by the spunlace method (spunlace nonwoven fabric), or nonwoven fabric manufactured by the needle punching method (needle punch nonwoven fabric), or a laminate of two or more of these nonwoven fabrics, or Examples include laminates of these nonwoven fabrics, other nonwoven fabrics, and other materials. Among them, spunbond nonwoven fabrics and meltblown nonwoven fabrics are preferred. A spunbonded nonwoven fabric has higher strength than other types of nonwoven fabrics, and is particularly preferable as a protective material for enhancing the strength of the sanitary mask sheet of the present invention. Moreover, the nonwoven fabric may contain an elastic body as described later.
There are no particular restrictions on the type of resin that constitutes these nonwoven fabrics, as long as it has fiber-forming ability. For example, polyolefin resin and polyester resin can be used. It preferably contains a thermoplastic fiber from the viewpoint of forming a joint portion 5M of a sanitary mask, which will be described later.

In particular, the sanitary mask sheet 10 preferably contains a fine fiber layer A having an average fiber diameter of 3000 nm or less. As a result, the sanitary mask sheet 10 not only has an extremely high collection property as described above, but also has an increased flexibility, making it easy to cause the above-described curling.
From this point of view, the average fiber diameter of the fine fiber layer A is more preferably 2000 nm or less, more preferably 1000 nm or less.
In addition, the average fiber diameter of the fine fiber layer A is preferably 200 nm or more, more preferably 300 nm or more, and 400 nm or more from the viewpoint of ensuring air permeability appropriately and making it easier for the user of the sanitary mask sheet to breathe easily. is more preferred.
Furthermore, the density of the fine fiber layer A is preferably 0.05 g/cm ³ or more, more preferably 0.1 g/cm ³ or more, and even more preferably 0.15 g/cm ³ or more. . As a result, it becomes possible to more effectively collect pollen, droplets, and particles smaller than these particles, and the strength of the fine fiber layer A can be improved.
In addition, the density of the fine fiber layer A is set to 0 from the viewpoint of ensuring appropriate air permeability to make it easier for the user of the sanitary mask sheet to breathe easily, reducing compression elasticity and realizing a soft touch. It is preferably 0.6 g/cm ³ or less, more preferably 0.55 g/cm ³ or less, and even more preferably 0.5 g/cm ³ or less.

(Average fiber diameter of fine fiber layer A)
The average fiber diameter of the fine fiber layer A can be measured by using a scanning electron microscope (SEM) for the maximum fiber cross-section perpendicular to the fiber length direction. The specific procedure is as follows.
After carefully peeling off the sanitary mask sheet and confirming how many layers it has, the layer with the smallest fiber diameter (the layer that functions as a filtering material) is taken as the fiber layer to be measured. From the two-dimensional image obtained by SEM observation, 500 fibers are arbitrarily selected from which defects such as fiber clumps, fiber-to-fiber intersections, and polymer droplets are removed, and the length of a line perpendicular to the longitudinal direction of the fiber is drawn. Read directly as fiber diameter. From the frequency distribution (histogram) of the measured fiber diameters, the median fiber diameter at which the cumulative frequency is 50% of the total is obtained, and this is taken as the average fiber diameter of the fibers constituting the fiber layer to be measured.

(Method for measuring density of fine fiber layer A)
The density of the fine fiber layer A can be measured by the following method. Specifically, the nonwoven structure is left in a natural state where no external force is applied, and the nonwoven structure is cut using a single-edged blade manufactured by Feather Safety Razor Co., Ltd. (product number FAS-10). Form a cross section.
Subsequently, using a scanning electron microscope (model number JCM-5100) manufactured by JEOL Ltd., a microscope, etc., the cut out cross section is enlarged and observed. The cross section observed under magnification is used as image data or printed matter, and the thickness of the fine fiber layer A is measured under no load. Fuzzy fibers, which are inevitably present on the surface of the non-woven structure, are excluded from the measurement. The thickness of the nonwoven structure is the average value of the thicknesses in the image observed under magnification by the method described above. In addition, when the fine fiber layer A has an uneven structure as shown in FIGS. (Apparent thickness in the thickness direction between the first surface 1S side and the second surface 1R side), but the thickness of the fiber layer itself along the undulations of the unevenness.
After that, the nonwoven structure left still in its natural state is cut into a predetermined area (for example, 2 cm × 2 cm), the fiber layers other than the fine fiber layer A are removed, and the mass and surface area of the fine fiber layer A are measured. is measured, and the basis weight is calculated by dividing the mass by the area. After that, the basis weight is divided by the thickness to calculate the density. When the fine fiber layer A has an uneven structure, the "predetermined area" to be cut means the area along the undulations of the unevenness (or the area when the unevenness is flattened). Further, the "surface area" of the fine fiber layer A means the uneven surface area S1 measured by the method described later in (Method for measuring the ratio of S1 to S0).

In addition, the basis weight of the sanitary mask sheet 10 is preferably 200 g/m ² or less, more preferably 170 g/m ² or less, and even more preferably 150 g/m ² or less, from the viewpoint of facilitating curling of the entire sheet.
The basis weight of the sanitary mask sheet 10 is preferably 40 g/m ² or more, more preferably 60 g/m ² or more, and even more preferably 80 g/m ² or more, from the viewpoint of increasing the strength of the sanitary mask sheet.

(Method for measuring basis weight)
A finely oriented sanitary mask sheet is allowed to stand in a natural state, cut into 20 mm squares, the mass (g) is measured, and the area of the cut sheet (400 mm ² = 0.0004 m ² ). Calculated by dividing by

The sanitary mask sheet 10 is composed of one sheet, as shown in FIG. It is preferably a sheet in which the low-elasticity sheet) 8 is laminated. The "stretchability" referred to here is the extent to which a sheet with a length of 100 is stretched to a length of 150 by applying a force in one direction and then divided by the original length of 100 by dividing the force. The height is judged by whether it can be contracted to the length of . For example, "high elasticity" refers to the property of stretching a sheet of length 100 to a length of 150 by applying force in one direction, and then shrinking to a length of 100 or more and 110 or less by dividing the force. . "Low stretchability" refers to the property that the material cannot be stretched to a length of 150 or that it does not shrink to a length of 100 or more and 110 or less when the force is divided even if it can be stretched, and is also called "non-stretchability".
In measuring the "stretchability" of the high-stretch sheet 96 and the low-stretch sheet 8, the sanitary mask sheet was allowed to stand in a natural state without external force, and a single-edged blade manufactured by Feather Safety Razor Co., Ltd. (product number FAS-10) was used. ) to cut to 20 mm x 50 mm. After that, the joint at the interface between the high-stretch sheet 96 and the low-stretch sheet 8 is cut using a razor, a cutter, scissors, or the like to separate the high-stretch sheet 96 and the low-stretch sheet 8, and each cut The piece can be stretched in the longitudinal direction and evaluated for "stretchability".

The following can be said about the mechanism by which the sanitary mask sheet 10 is easily rolled up. For example, when the sanitary mask sheet 10 is stretched by applying a tensile load in one direction, the low-stretch sheet 8 tends to retain residual strain more than the high-stretch sheet 96 . Therefore, when the tensile load is removed, a relatively high shrinkage force is applied to the surface on the high-stretch sheet 96 side compared to the low-stretch sheet. As a result, the sanitary mask sheet 10 can be easily rolled up toward the highly stretchable sheet 96 . In addition, the low-stretch sheet 8 has a plurality of protrusions 61 that protrude outward in the thickness direction in a natural state on one surface 1S as shown in FIG. When the sheet for sanitary mask 10 has the sandwiched recesses 62 , a force acts to restore the uneven shape to a flat shape, and the sanitary mask sheet 10 tends to be rolled up toward the highly stretchable sheet 96 .
Therefore, in the sanitary mask sheet 10, the surface of the low-stretch sheet 8 is preferably the one surface 1S described above, and the surface of the high-stretch sheet 96 is preferably the opposite surface 1R described above. As a result, the end portion of the sanitary mask sheet 10 can be curled from the one surface 1S on which the low-stretch sheet 8 is arranged to the opposite surface 1R on which the high-stretch sheet 96 is arranged.

In the sanitary mask sheet 10 , it is preferable that at least the longitudinal direction X has the above-described stretchability, from the viewpoint of curling at least at the ends 11 in the longitudinal direction X. Moreover, it is more preferable that the film has the above-mentioned stretchability in the longitudinal direction X and the transverse direction Y, and more preferably that it has the above-mentioned stretchability in multiple directions including these directions.

Examples of the highly stretchable sheet 96 include a nonwoven fabric made of stretchable fibers, a nonwoven fabric made of stretchable fibers and non-stretchable fibers, and a composite nonwoven fabric of a non-stretchable nonwoven fabric and an elastic body (for example, elastic filaments). .
As the low-stretch sheet 8, for example, a non-woven fabric made of non-stretch fibers can be used.

The highly stretchable sheet 96 is preferably a nonwoven fabric containing elastic filaments, and more preferably a composite nonwoven fabric of a non-stretchable nonwoven fabric and an elastic body (for example, elastic filaments). A non-woven fabric in which stretchable fibers or elastic fibers and non-stretchable fibers are mixed may be used. In either case, it is preferable to apply a stretching treatment, which will be described later.
In particular, the highly stretchable sheet 96 is preferably made of a composite nonwoven fabric in which a pair of non-stretchable nonwoven fabrics 94, 94 as shown in FIG.

The elastic filaments 95 are preferably bonded in a substantially non-stretched state to non-woven fabrics 94, 94 comprising inelastic fibers. Also, it is preferable that a plurality of elastic filaments 95 are joined to the pair of nonwoven fabrics 94 , 94 .
The plurality of elastic filaments 95 are preferably arranged so as to extend in the longitudinal direction X without intersecting each other. In addition, the sanitary mask sheet 10 having the highly stretchable sheet 96 has the advantage that when stretched in the direction in which the elastic filaments 95 extend, the width orthogonal to the direction is less likely to shrink. .
Each elastic filament 95 may extend linearly or meanderingly as long as it does not cross each other. Moreover, it is preferable that the plurality of elastic filaments 95 are arranged at intervals in the lateral direction Y orthogonal to the longitudinal direction X. As shown in FIG.

Such a highly stretchable sheet 96 can typically be produced by the method described in paragraphs [0055] to [0085] of JP-A-2008-179128. Specifically, a pair of non-stretchable non-woven fabrics 94, 94 are bonded to a melted elastic filament 95 in a non-stretched state to produce a non-stretched composite material. A highly stretchable sheet 96 is obtained by passing the composite material between a pair of tooth groove rolls arranged opposite to each other so as to be able to mesh with each other, thereby performing a stretching process to exhibit stretchability.

In addition, as shown in FIG. 6A, the sanitary mask sheet 10 of the present embodiment has a plurality of projections 61 projecting outward in the thickness direction in a natural state and a plurality of projections on one surface 1S. It is preferable to have a recess 62 sandwiched between 61 . This concave-convex structure provides room for expansion on the one surface 1S, making it easier to cause the edge of the sheet 10 to turn over on the opposite surface 1R side.

The planar arrangement pattern of the projections 61 and the recesses 62 can be variously set within a range that does not hinder the above-described curling. For example, there is a ridged and grooved pattern in which both the convex portions 61 and the concave portions 62 continuously extend in one direction, and both the convex portions 61 and the concave portions 62 are alternately arranged in the other direction crossing the one direction. be done.
Further, as a different example, there is a pattern in which the convex portions 61 are arranged in a scattered pattern in the plane direction on the one surface 1S (not shown). Also in this scattered arrangement pattern, the convex portions 61 are regularly spaced apart in the one direction, that is, the convex portions 61 and the concave portions 62 form rows in which the convex portions 61 and the concave portions 62 are alternately and regularly arranged in the one direction. preferably. As a result, the projections 61 are intermittently arranged to extend in the one direction.

The other direction that intersects with the above one direction can be arbitrarily determined, and is preferably a direction orthogonal to each other. Moreover, the other directions that intersect with the one direction are preferably the lateral direction Y and the longitudinal direction X of the sheet 10 . Furthermore, the one direction is directed along the midline connecting the nose, mouth and chin of the wearer in the sanitary mask, and the other intersecting direction is directed in the direction from the mouth to the ears of the wearer in the sanitary mask. preferably.
When the other direction is the longitudinal direction X of the sheet 10 and is oriented in the direction from the mouth to the ear of the wearer in the sanitary mask 500, the direction in which the convex portions 61 and the concave portions 62 are alternately arranged is also oriented in the same direction. . As a result, in the manufacturing process of the sanitary mask 500 shown in FIG. The end portion 512A of the outer edge of the hole portion 512 is more likely to curl. As a result, the cut cross section of the sanitary mask 500 is less likely to stick, and even if part of it sticks, it can be peeled off naturally. As a result, the sanitary mask 500 to be manufactured is easier to grip at the end, and is easier to open during use.

Furthermore, it is preferable that the projections 63 and the recesses 64 are arranged on the opposite surface 1R side of the one surface 1S on which the projections 61 and the recesses 62 are arranged, from the viewpoint of increasing the flexibility and making it easier to turn over. The protrusions 63 and the recesses 64 on the opposite surface 1R can have various arrangement patterns.
For example, as shown in FIG. 6A, convex portions 63 and concave portions 64 may be arranged on the opposite surface 1R of the low-stretch sheet 8 . In addition, convex portions 63 and concave portions 64 may be arranged on the opposite surface 1R of the highly elastic sheet 96 (the opposite surface 1R of the sanitary mask sheet 10) (not shown). In the latter case, the concave-convex sheets are arranged on both sides of the sanitary mask sheet 10, and it is necessary that the straightening force of the concave-convex sheets arranged on one surface 1S and the opposite surface 1R is uneven. Become.
In the former case, for example, as shown in FIG. 6(A), the convex portions 63 on the opposite surface 1R are arranged in a front-back relationship corresponding to the concave portions 62 on the one surface 1S, and the concave portions 64 on the opposite surface 1R correspond to the concave portions 64 on the one surface 1S. An arrangement pattern in which the front and back are arranged corresponding to the convex portion 61 is preferable. As a result, the projections 61 and 63 become hollow, are more flexibly deformable, and are more likely to curl as described above, which is preferable.

In particular, in the sanitary mask sheet 10 of the present embodiment, as shown in FIG. 6(A), the low-stretch sheet 8 is preferably an uneven sheet. The concave-convex sheet preferably has a concave-convex structure in which convex portions 61 and concave portions 62 continuously extend in the lateral direction Y and are alternately arranged in the longitudinal direction X on one surface 1S. It is preferable that the projections 63 and the recesses 64 extend continuously in the lateral direction Y and are alternately arranged in the longitudinal direction X on the opposite surface 1R side of the uneven sheet. It is preferable that such a corrugated uneven sheet is present on the one surface 1S side. As a result, the sanitary mask sheet 10 has more room to expand and contract in the longitudinal direction X, making it easier for the aforementioned curling to occur more effectively.

Furthermore, as shown in FIG. 6A, the sanitary mask sheet 10 of the present embodiment can be a laminate of the low-stretch sheet 8 as the uneven sheet and the high-stretch sheet 96. preferable. It is preferable to arrange the uneven low-elasticity sheet 8 on the aforementioned one surface 1S and arrange the high-elasticity sheet 96 on the opposite surface 1R.
In such a structure, in the sanitary mask sheet 10 of the present embodiment, the highly elastic sheet 96 on the opposite surface 1R side contracts as shown in FIG. 6(B). Along with this, the concave-convex structure of the low-elasticity sheet 8 on the one surface 1S stretches to become flat and takes a movement to warp toward the opposite surface 1R.
As a result, in the sanitary mask sheet 10 of the present embodiment having the structure of FIG. 6A, as shown in FIG. The turn part 13 can be sufficiently formed.

When the sanitary mask sheet 10 of the present embodiment has a structure as shown in FIG. 7, it can be manufactured by various methods commonly used for this type of article.
In particular, it is preferably obtained by the following manufacturing method.
That is, as shown in FIGS. 8(A) to 8(C), a raw sheet 800 of the low-stretch sheet 8 that has not been unevenly formed is obtained by stretching the high-stretch sheet 96 along its stretching direction. to stack. In this state, at the same time, the portion 802 of the raw fabric sheet 800 that will be the bottom of the concave portion 62 and the highly stretchable sheet 96 at that position are point-joined. Thereafter, the stretch of the highly stretchable sheet 96 is released and contracted. As a result, the raw sheet 800 is deformed into an uneven shape, and an uneven low-stretch sheet 8 partially joined to the high-stretch sheet 96 at the recesses 62 is formed. This manufacturing method makes it possible to shape irregularities while preventing breakage of the fine fiber layer A, even if the fine fiber layer A is used as the constituent material of the raw fabric sheet 800 . As a result, the sanitary mask sheet 10 as shown in FIG. 7 can be manufactured efficiently with high accuracy.

The sanitary mask sheet 10 of this embodiment has a structure as shown in FIG. 2) is preferably arranged as shown in FIG.
That is, it is preferable that the protrusions 61, 61 of the low-stretch sheets 8, 8 facing each other inwardly are arranged with one surface 1S of the sanitary mask sheet 10 facing inward. As a result, the protrusions give cushioning properties to the overlapping structure 50, and exert a resistance against the cut-out pressure for manufacturing the sanitary mask as described above. As a result, the cut cross section is less likely to stick, the end of the sanitary mask 500 is easier to grip, and the ease of unfolding is further improved.

Although FIG. 9 shows that the uneven low-elasticity sheet 8 has two layers, it is not limited to this, and may have one layer or three or more layers.
Regardless of how many layers the uneven low-elasticity sheet 8 has, it is preferable that at least one layer is the fine fiber layer A described above. Thereby, in the sanitary mask to be manufactured, it is possible to enhance the ability to collect fine particles and the like, and to soften the touch.
Further, when the uneven low-elasticity sheet 8 has two layers as shown in FIG. As a result, the protective layer 81 becomes the outermost layer, and as a skin-contacting layer in the sanitary mask, it protects the fine fiber layer A from direct application of external force, and can suppress deterioration in performance due to breakage or the like. As the protective layer 81, a material having good texture and excellent durability can be used without particular limitation. For example, a spunbond nonwoven fabric is preferably used.

In the sanitary mask sheet 10, the height of the protrusions 61 on one surface 1S is preferably as follows in the natural state. The "height of the convex portion 61" referred to here means that when the sanitary mask sheet 10 is placed on a horizontal surface with the other surface 1R facing down and the side surface is viewed, the convex It means the height difference E in the thickness direction between the top of the portion 61 and the surface of the bottom of the recess 62 adjacent to the projection 61 on the one surface 1S side. The thickness direction at this time means a direction perpendicular to the horizontal plane on which the sanitary mask sheet 10 is placed.
The height of the protrusions 61 on the one surface 1S in the natural state is preferably 1 mm or more, more preferably 1.5 mm or more, and even more preferably 2 mm or more. Such a height difference is much larger than that of ordinary embossing. Thereby, the cushioning property of the sanitary mask sheet 10 in the convex portion 61 is enhanced, and the soft touch can be further improved.
In addition, the height of the projections 61 on one surface 1S is preferably 4 mm or less, more preferably 3.5 mm or less, and even more preferably 3 mm or less in a natural state. Thereby, the shape stability of the convex portion 61 is enhanced. As a result, even when the sanitary mask sheet 10 is repeatedly used or used for a long period of time, it is possible to maintain both the above-described high ability to trap particles and the like and the soft touch for a longer period of time.

(Method of measuring height difference E in the thickness direction between the top of the convex portion 61 and the surface of the bottom portion of the concave portion 62 adjacent to the convex portion 61 on the one side 1S side)
The aforementioned height difference E can be measured by the following method.
First, as shown in FIG. 10(A), T1 is measured as the thickness between the front and back surfaces of the sanitary mask sheet 10 . This refers to the vertical height from the position of the horizontal surface to the top of the convex portion 61 when the opposite surface 1R of the sanitary mask sheet 10 is placed on a horizontal surface. Therefore, T1 is the vertical thickness of the uneven low-stretch sheet 8 and the high-stretch sheet 96 as a whole.
Next, T2 is measured as the height of the surface of the bottom of the recess 62 on the side of the one surface 1S. This refers to the vertical height from the position of the horizontal plane described above to the surface of the bottom of the recess 62 on the side of the one surface 1S.
Based on the above measurements, the height difference E can be calculated as T1-T2.
As a specific measuring method, the cross section in the thickness direction of the sanitary mask sheet 10 is enlarged with a microscope, and the height difference E, in other words, the height E of the hollow space is directly measured from the image processing. Alternatively, the height difference E may be calculated by scanning a laser displacement meter from the upper surface of the mask sheet 10 to measure T1 and T2. It should be noted that the definition of the height difference E is the same regardless of whether the uneven low-stretch sheet 8 consists of the fine fiber layer A alone or the fine fiber layer A and the protective sheet 81, so measurement is performed in the same manner. do it.

The thickness (T1) between the front and back surfaces of the sanitary mask sheet 10 can effectively reduce airflow resistance to facilitate breathing, and the uneven sheet 8 ensures cushioning properties and maintains a soft touch. Therefore, it is preferably 1 mm or more, more preferably 1.5 mm or more, and still more preferably 2 mm or more.
In addition, the thickness (T1) between the front and back surfaces of the sanitary mask sheet 10 is preferably 5 mm or less, more preferably 4.5 mm or less, from the viewpoint of improving the handleability of the sanitary mask sheet 10 and improving the appearance. 4 mm or less is more preferable.

Furthermore, in the natural state of the sanitary mask sheet 10, the center-to-center distance between the adjacent convex portions 61, that is, the pitch of the convex portions 61, in plan view on the one side 1S side on which the uneven low-stretch sheet 8 is arranged, is It is preferably 6 mm or less, more preferably 5 mm or less, and even more preferably 4 mm or less. As a result, the sanitary mask sheet 10 can efficiently increase the surface area constituted by the unevenness, effectively reduce airflow resistance, and facilitate breathing. In addition, the contact area with the skin can be reduced, the friction with the skin can be greatly reduced, and the feeling of wearing the sanitary mask sheet 10 and the sanitary mask using the same can be further enhanced.
In addition, in a plan view of the sanitary mask sheet 10 in a natural state, the distance between the centers of adjacent convex portions 61 is preferably set to 1 mm or more, more preferably 1.5 mm or more, and 2 mm or more. Setting is more preferable. Thereby, the shape stability of the convex portion 61 is enhanced. As a result, even when the sanitary mask sheet 10 is repeatedly used or used for a long period of time, it is possible to maintain both the above-described high ability to trap particles and the like and the soft touch for a longer period of time.

In addition, in the natural state of the sanitary mask sheet 10, the area when viewed from the side of one surface 1S on which the low-elasticity sheet 8 having the uneven structure is arranged is preferably as follows.
First, let S0 be the unit area when one surface 1S side of the sanitary mask sheet 10 is viewed in plan view, and let S1 be the surface area of the unevenness in the unit area S0. At this time, it is preferable that the value of S1 is larger than the value of S0 because one surface 1S of the low-stretch sheet 8 has an uneven structure. That is, the one surface 1S side of the sanitary mask sheet 10 has an uneven structure, so that the effective area through which air passes increases compared to the case where the one surface 1S side of the sanitary mask sheet 10 does not have an uneven structure. . By increasing the effective area, the ventilation resistance of the sheet 10 can be effectively reduced. In addition, the filtration effective area for the above-mentioned particles and the like increases, making it easier to increase the above-mentioned collection efficiency.
From this point of view, in the natural state of the sanitary mask sheet 10, the ratio (S1/S0) of the uneven surface area S1 per unit area S0 in plan view is preferably more than 1, and 1.3 or more. is more preferable, and 1.5 or more is even more preferable.
In addition, from the viewpoint of the shape stability of the projections 61, in the natural state of the sanitary mask sheet 10, the ratio of the uneven surface area S1 per unit area S0 in plan view is preferably 3 or less. It is more preferably 8 or less, and even more preferably 2.5 or less.

(Method for measuring the ratio of S1 to S0)
The low-elasticity sheet 8 having the concave-convex structure that constitutes the sanitary mask sheet 10 is left in a natural state and cut into an arbitrary area S0′ (eg, 10 cm×10 cm=100 cm ² ). The area S1′ of the cut uneven sheet 8 when flat without wrinkles is measured, and the ratio of S1 to S0 is calculated from the following equation.
S1/S0=S1'/S0'
However, when the low-elasticity sheet 8 having an uneven structure is joined to another sheet as described later, depending on the joining state, the low-elasticity sheet 8 may undergo plastic deformation during delamination. There is In such a case, for example, at the convex portion 61 where the uneven low-stretch sheet 8 and the high-stretch sheet 96 are separated as shown in FIG. (the position of the upward arrow) and divide the high-stretch sheet 96 into individual independent pieces. By doing so, the low-elasticity sheet 8 can be spread out in a flat state (FIG. 10(B)), so that S1′ can be measured. When the uneven low-stretch sheet 8 is a laminate of the fine fiber layer A and the protective sheet 81 as described later, these are integrated and measured by the same method as above.

The sanitary mask sheet of this embodiment has a structure as shown in FIG. 7, and based on this, a sanitary mask 500 manufactured as shown in FIGS. 3(A) and 3(B) is shown in FIG. Thus, the end portion 502A of the ear hook portion 502 in particular is greatly curled, and the winding portion 13 extending to the opening portion 512 may be generated. As a result, sticking of the cut cross section is eliminated in a wide range of the ear hook portion 502A, and easiness of picking and opening during use is remarkably improved.
From the viewpoint of further enhancing this effect, as described above, it is more preferable that the convex portions 61, 61 are arranged to face each other.
It should be noted that the sanitary mask is preferably curled in the outer direction of the sanitary mask as shown in FIG. Even if the sanitary mask is curled inward, the cut surface is peeled off and the contact surface is lifted, so that the above effects can be sufficiently obtained.

In addition, when the sanitary mask 500 is used, when the ear hooking portion 502 is hung on the ear E of the user W, as shown in FIG. abuts behind the ear. In this way, the end portion 502A of the ear hooking portion 502 becomes the winding portion 13 and three-dimensionalized, so that the sanitary mask 50 has cushioning properties against the back of the ear. Further, even when the winding part 13 is crushed by hitting the back of the ear, it is easy to come into contact with the ear. As a result, the sanitary mask 500 reduces the burden on the back of the ear, provides a comfortable wearing feeling, and can be worn for a long time. In addition, in FIG. 12, the mask body is omitted for the purpose of understanding the action of the ear hook portion on the back of the ear.

The sanitary mask sheet of the present invention can be used not only as the sanitary mask 500 itself but also as a filter sheet 503 detachable from the sanitary mask 500 . For example, as shown in FIG. 13, the sanitary mask sheet 10 of the present embodiment can be used as the filter sheet 503 in a sanitary mask 500 having a sanitary mask main body 501 and a filter sheet 503 disposed inside thereof. can.

The sanitary mask 500 and the filter sheet 503 using the sanitary mask sheet of the present invention are not limited to the above-described embodiments, and can take various forms as long as their functions are not impaired.
For example, only the sanitary mask body 501 may be made of the sanitary mask sheet of the present invention, and the ear hooks 502 may be made of another material such as a rubber cord or stretchable nonwoven fabric. Other materials such as a meltblown nonwoven fabric or a polyurethane porous sheet may be used, and only the ear hook portion 502 may be made of the sanitary mask sheet of the present invention.
Moreover, the sanitary mask 500 and the filter sheet 503 to which the sanitary mask sheet of the present invention is applied may have a rectangular shape in plan view instead of a three-dimensional shape. Furthermore, the sanitary mask 500 and the filter sheet 503 may have several laterally extending pleats.

EXAMPLES The present invention will be described in more detail below based on examples, but the present invention should not be construed as being limited thereto. In the examples, "parts" and "%" are based on mass unless otherwise specified.

(Example)
A sanitary mask sheet sample shown in FIG. 7 was produced by the manufacturing method shown in FIG.
The highly stretchable sheet consisted of the highly stretchable sheet 96 shown in FIG. 5 and was manufactured by the following method.
Two spunbond nonwoven fabrics made of polypropylene (hereinafter also referred to as PP) resin having an average fiber diameter of 18 μm and a basis weight of 18 g/m ² were used, and a plurality of elastic filaments having a diameter of 100 μm were arranged between the two nonwoven fabrics. . The total basis weight of the elastic filaments was 9 g/m ² . This laminated sheet was passed between a pair of tooth groove rolls to exhibit stretchability to produce a highly stretchable sheet 96 .
A low-stretch sheet 8 was produced by the following method.
A spunbond nonwoven fabric made of PP resin having an average fiber diameter of 15 μm and a basis weight of 18 g/m ² was prepared as a protective sheet. Thereafter, fibers spun by an electrospinning method are deposited on the protective sheet, and a fine fiber layer A (material: PP resin, average fiber diameter 500 nm, basis weight 3 g/m ² ) is laminated on the protective sheet to achieve low stretchability. A raw sheet 800 of a flexible sheet was prepared.
After that, according to the method shown in FIG. 8 , the high-stretch sheet is stretched 1.7 times, and the raw sheet 800 of the low-stretch sheet is overlapped and joined to form a sanitary mask sheet. manufactured.
The height of the protrusions of the uneven sheet 8 was 2 mm, the pitch was 3 mm, and the ratio of the surface area S1 of the unevenness per unit area S0 (S1/S0) was 1.7.
A sanitary mask sample shown in FIG. 11 was produced from the sanitary mask sheet sample by the manufacturing method shown in FIG. At that time, in cutting the sanitary mask sheet sample into a mask shape, a Thomson blade having the mask shape was prepared, and the mask shape was cut out by pressing the Thomson blade. In the obtained sanitary mask sample, curling was observed on the end face of the sanitary mask, and it was confirmed that there was a state in which the cut surfaces were not joined.

(Comparative example 1)
As a sanitary mask sheet sample, a meltblown nonwoven fabric (trade name “Tapirus”, manufactured by Tapyrus Co., Ltd., material PP resin, average fiber diameter 1.5 nm, basis weight 7 g / m ² ) was used, and it was sanitized by the manufacturing method shown in FIG. A mask sample was made. At that time, in cutting the sanitary mask sheet sample into a mask shape, a Thomson blade having the mask shape was prepared, and the mask shape was cut out by pressing the Thomson blade. No curling was observed on any of the sanitary mask end faces of the obtained sanitary mask sample.
(Comparative example 2)
Example 1 except that a spunbond nonwoven fabric (trade name “NW-LIVSEN SSSS SM17”, manufactured by Toray Industries, Inc., material PP resin, average fiber diameter 15 nm, basis weight 18 g / m ² ) was used as a sanitary mask sheet sample. A sanitary mask sample was prepared in the same manner. No curling was observed on any of the sanitary mask end faces of the obtained sanitary mask sample.

(test)
Using a sanitary mask cut into a mask shape by pressing the Thomson blade in the manufacturing method shown in FIG. After that, it was observed whether or not the cut surface of the sanitary mask was stuck together.
As a result, in Example 1, it was confirmed that the cut surfaces were separated (Fig. 14), but in Comparative Examples 1 and 2, the cut surfaces remained attached (Figs. 15 and 16). .

10 Sanitary mask sheet 1S One surface 1R Opposite surface 11 Longitudinal end 12 Width direction end 13 Winding part 14 Sheet upper layer 14A Sheet upper layer end 15 Sheet lower layer 15B Sheet lower layer end X Longitudinal direction Y: Transverse direction 50: Layered structure 5S, 5R: Exposed surface 500 of layered structure: Sanitary mask 501: Mask main body part 502: Ear hook part 512: Opening part 501A: End part 502A along the outer shape of the mask main body part: Along the outer shape of the ear hook part Edge 512A Edge 5M of the outer edge of the opening Sanitary mask junction 61 Convex 62 Concave 63 Convex 64 Concave 8 Low-stretch sheet 81 Protective layer 96 High-stretch sheet

Claims (11)

A sanitary mask sheet whose ends are curled in a natural state. The sanitary mask sheet according to claim 1, wherein a sheet having relatively high elasticity and a sheet having relatively low elasticity are laminated. The sanitary mask sheet has one side and the other side,
3. The sanitary mask sheet according to claim 1, wherein said one surface has a plurality of protrusions protruding outward in the thickness direction in a natural state and recesses sandwiched between the plurality of protrusions. The sanitary mask sheet according to any one of claims 1 to 3, which has a layered structure in which the one surface faces inward and is folded into two layers or two layers are stacked. 5. The sanitary mask sheet according to claim 4, wherein the edges of the sanitary mask sheet are curled outward from the layered structure in a natural state. The sanitary mask sheet according to claim 4 or 5, wherein the protrusions are arranged inside the overlapping structure. The sanitary mask sheet according to any one of claims 1 to 6, wherein the cut cross section can be naturally rolled up when cut into the sanitary mask shape. Equipped with an ear hook and a sanitary mask main body,
A sanitary mask, wherein the ear hooking portion is composed of the sanitary mask sheet according to any one of claims 1 to 7, and the edge of the ear hooking portion is turned up. Equipped with a sanitary mask body,
A sanitary mask, wherein the sanitary mask main body is composed of the sanitary mask sheet according to any one of claims 1 to 7, and the end of the mask main body is turned up. A sanitary mask body and a filter sheet detachable from the sanitary mask body,
A sanitary mask, wherein the filter sheet comprises the sanitary mask sheet according to any one of claims 1 to 7. A method of using a sanitary mask sheet, wherein the mask sheet according to any one of claims 1 to 7 is used as a filter sheet detachable from a sanitary mask body in a sanitary mask.

Images