Absorbent article

Abstract

In the absorptive article, the outer edges of a pair of side wing parts (6S and 6S) are provided with a pair of rear convex parts (65 and 65) in a rear area (R), and the rear convex parts (65 and 65) are closer to the front in the longitudinal direction (X) than the longitudinal rear ends (the longitudinal rear end (1R) of a sanitary towel (1)) of the side wing parts (6) and protrude towards the outer side in the transverse direction (Y) than the peripheral parts. The portion of the outer edge of the wing section (6) sandwiched between the longitudinal rear end (1R) and the rear convex section (65) has an inward convex curved section (66) having a center of curvature on the outside of the outer edge. The inward-convex curved section (66) has a single curved shape comprising a curved line extending from the longitudinal rear end (1R) and the rear convex section (65) as a starting point and from each of the two starting points (1R, 65) toward a single convex apex (66P) located between the two starting points (1R, 65), and the apex (66P) is located forward of the longitudinal rear end (4R) of the absorbent body (4) in the longitudinal direction (X).

Description

Technical Field

[0001] The utility model relates to an absorbent article which is worn on the crotch and used for absorbing excrement. Background Art

[0002] As a female absorbent article represented by sanitary napkins, there is known an absorbent article including an absorbent body for absorbing and retaining excreta such as menstrual blood, and wings extending outward from the outer edge of the absorbent body to form the outline of the absorbent article (Patent Documents 1 to 4).

[0003] The absorbent articles described in Patent Documents 1 to 3 include a fin portion that includes a portion of the longitudinal central portion of the portion (side wing portion) located on both sides of the absorbent body, and extends to a greater extent to the outside in the transverse direction than the peripheral portion. The "longitudinal direction" referred to herein refers to the direction corresponding to the front-back direction of the wearer of the absorbent article, and the "transverse direction" refers to the direction orthogonal to the longitudinal direction. When the absorbent article is fixed to the skin-facing surface (inner surface) of the crotch of clothing such as shorts, the fin portion is artificially folded to the non-skin-facing surface (outer surface) side of the crotch with fingers and used, and the fixing portion is arranged on the surface opposite to the non-skin-facing surface of the crotch of the clothing when folded. On the other hand, in the absorbent article described in Patent Document 4, the extension length of the side wing portion to the outside in the transverse direction is relatively short, and the fixing portion is not arranged on the side wing portion. When worn, the side wing portion is not folded to the non-skin-facing surface side of the clothing, but extends downward along the wearer's legs (Patent Document 4

[0058] ).

[0004] In the absorbent article described in Patent Document 2, the portion of the side wing portion located longitudinally rearward of the fin portion extends laterally outward to the same extent as the fin portion to form a buttocks retaining portion. Patent Document 2 states that the outer contour (outline) of the buttocks retaining portion is designed so that the buttocks retaining portion can fit well along the shape of the wearer's buttocks and prevent the buttocks retaining portion from curling. In addition, the absorbent article described in Patent Document 3 has a Figure 1 In the figure, two contour lines extending longitudinally forward and laterally outwardly with the rear end of the absorbent article as a starting point each have two convex portions, and between the convex portion on the longitudinal front side of the two convex portions and the rear end of the absorbent article, there are two inwardly curved portions.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2020-5845

[0008] Patent Document 2: Japanese Patent Application Publication No. 2018-29842

[0009] Patent Document 3: Japanese Patent Application Publication No. 2020-146089

[0010] Patent Document 4: International Publication No. 2019 / 26176 Summary of the invention

[0011] The utility model relates to an absorbent article, which has an absorbent body capable of absorbing and retaining body fluids, and has a longitudinal direction corresponding to the front-to-back direction of a wearer and a transverse direction orthogonal to the longitudinal direction, and has an excretion portion relative area arranged relative to the excretion portion of the wearer when worn, a front area arranged at a position forward of the longitudinal direction than the excretion portion relative area, and a rear area arranged at a position rearward of the longitudinal direction than the excretion portion relative area.

[0012] In one embodiment, it is preferred that a wing portion extends outward from the outer edge of the absorbent body to form the outline of the absorbent article, the wing portion has a pair of side wing portions located on the outside of the transverse direction than a pair of imaginary straight lines passing through the outermost end of the transverse direction of the absorbent body and extending in the longitudinal direction, and the absorbent body is located on the inside of the transverse direction of the side wing portions.

[0013] In one embodiment, preferably, the outer edges of the pair of side wings have a pair of rear convex portions in the rear region, which are located forward of the longitudinal rear ends of the wings and protrude outward in the transverse direction than the peripheral portions.

[0014] In one embodiment, preferably, a portion of the outer edge of the wing portion sandwiched between the longitudinal rear end of the wing portion and the rear convex portion has an inwardly convex curved portion having a center of curvature outside the outer edge.

[0015] In one embodiment, preferably, the inward convex curved portion is a single curved shape consisting of curved lines extending from the longitudinal rear end of the wing portion and the rear convex portion as starting points to a single convex top located between the two starting points, and the top is located closer to the longitudinal front side than the longitudinal rear end of the absorbent body.

[0016] Other features, effects and implementation modes of the present invention are described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic plan view of the skin-opposing side of a sanitary napkin as one embodiment of the absorbent article of the present invention.

[0018] Figure 2 It is along Figure 1 Schematic cross-sectional view of the cross section along line II (the cross section along the thickness direction and the transverse direction of the sanitary napkin).

[0019] Figure 3 yes Figure 1 A schematic plan view of the skin-opposing side of the rear area of ​​a sanitary napkin is shown.

[0020] Figure 4 middle, Figure 4 (a)~ Figure 4 (c) is a diagram for explaining a method for measuring a torque value.

[0021] Figure 5 yes Figure 3 A magnified view of a portion of .

[0022] Figure 6 yes Figure 1 The shown schematic cross-sectional views are cross-sectional views of the sanitary napkin in the worn state along the thickness direction and the transverse direction.

[0023] Figure 7 middle, Figure 7 (a)~ Figure 7 (b) is a schematic plan view of the skin-opposing side of the sanitary napkins of Experimental Examples 2 to 3.

[0024] Figure 8 middle, Figure 8 (a)~ Figure 8 (c) is a schematic plan view of the skin-opposing side of the sanitary napkins of Experimental Examples 4 to 6. DETAILED DESCRIPTION

[0025] Extending the side wings of the rear area of ​​the absorbent article laterally outwardly relative to the peripheral portion to make it wider, like the buttocks retaining portion described in Patent Document 2, is effective in preventing excrement from leaking from the rear, but on the contrary, it may cause strong discomfort to the wearer, especially with respect to the buttocks. That is, the rear area of ​​the absorbent article is a portion corresponding to the buttocks of the wearer, and is a portion that is easily subjected to relatively large external forces when the wearer walks. If the rear area is formed to be wide, it is difficult for the rear area to deform when subjected to external forces, and the ability of the rear area to follow the wearer's body is reduced, which can easily cause the wearer to feel discomfort (the feeling that the absorbent article does not correspond to the movement of the body). In addition, when the document Figure 1 When the top of the inwardly convexly curved portion near the rear end of the buttocks holding portion H is located further back in the front-rear direction than the rear end of the absorber 4, wrinkles and bends occur at a high frequency in the inwardly convexly curved portion, which is likely to cause discomfort to the wearer.

[0026] In addition, in the absorbent article of Patent Document 3, a plurality of inwardly curved portions are formed between the rear end thereof and the convex portion located in the rear area. Therefore, the convex portion between two adjacent inwardly curved portions is easily affected by the external force generated by the wearer's body movement. Therefore, the followability of the above-mentioned inwardly convexly curved portion to the external force is reduced, and wrinkles and bends may occur at a high frequency in the inwardly convexly curved portion.

[0027] There has not yet been provided an absorbent article which has excellent leakage-proof properties, is less likely to cause leakage of excrement, and flexibly deforms when the wearer walks without causing the wearer to feel discomfort.

[0028] The utility model relates to an absorbent article with excellent leakage prevention and wearing feeling.

[0029] Hereinafter, the present invention will be described based on its preferred embodiment with reference to the accompanying drawings. In addition, in the following description of the accompanying drawings, the same or similar parts are marked with the same or similar reference numerals. The accompanying drawings are basically schematic, and the ratio of each dimension, etc. may be different from the actual.

[0030] Figure 1 to Figure 3 A sanitary napkin 1 (hereinafter also referred to as "sanitary napkin 1") is shown as one embodiment of the absorbent article of the present invention. The sanitary napkin 1 has a longitudinal direction X corresponding to the front-back direction of the wearer and extending from the front side (ventral side) of the wearer through the crotch to the rear side (dorsal side) and a lateral direction Y orthogonal to the longitudinal direction X.

[0031] In the present invention, “longitudinal front” refers to a position further forward (abdomen of the wearer) than a reference position in the longitudinal direction, and “longitudinal rear” refers to a position further rearward (back side of the wearer) than a reference position in the longitudinal direction.

[0032] In this embodiment, if Figure 1 As shown, the sanitary napkin 1 is long in the longitudinal direction X, and its length direction is consistent with the longitudinal direction X.

[0033] In this embodiment, the sanitary napkin 1 is formed symmetrically on one side and the other side with respect to the transverse center line CLy. Figure 1 The sanitary napkin 1 in the unfolded state shown is divided into two equal parts in the transverse direction Y and an imaginary straight line extending in the longitudinal direction X.

[0034] The sanitary napkin 1 has an absorbent body 4 that can absorb and retain body fluids (menstrual blood, urine, feces, sweat, etc.). In addition, the sanitary napkin 1 preferably also has a liquid-permeable front sheet 2 that can contact the wearer's skin and a leak-proof back sheet 3. In this case, Figure 2As shown, the absorbent body 4 is arranged between the front sheet 2 and the back sheet 3. In the sanitary napkin 1, the front sheet 2 covers the entire area of ​​the skin-opposite surface of the absorbent body 4, and the back sheet 3 covers the entire area of ​​the non-skin-opposite surface of the absorbent body 4. As the two sheets 2, 3, the sheets commonly used in such absorbent articles can be used without special restrictions. As the front sheet 2, various sheets with liquid permeability can be used, for example, nonwoven fabrics, woven fabrics, and paper can be cited. As the back sheet 3, a sheet with leakproofness can be used, specifically, a sheet with liquid impermeability (the property of not permeating liquid at all) or liquid difficulty permeability (although it cannot be said to be liquid impermeability, it is difficult to permeate the property of liquid) can be used, for example, a resin film with moisture permeability, a laminate of the resin film and a nonwoven fabric can be cited.

[0035] In this embodiment, if Figure 1 As shown in FIG. 1 , a pair of side panels 5, 5 are arranged on both sides of the skin-facing surface of the sanitary napkin 1 (the skin-facing surface of the front sheet 2) along the longitudinal direction X. The pair of side panels 5, 5 are arranged along the substantially full length of the longitudinal direction X in a manner overlapping with both sides of the absorbent body 4 along the longitudinal direction X when viewed from above. Figure 2 As shown, the outer side of the side piece 5 along the two sides of the longitudinal direction X, including the outer side edge located outside the transverse direction Y, is formed as a fixed edge fixed to other components (in the illustrated manner, it is the back sheet 3), and the inner side including the inner side edge located inside the transverse direction Y is formed as a free edge not fixed to other components. When the sanitary napkin 1 is worn, the above-mentioned free edge of the side piece 5 stands up to the skin side of the wearer, thereby preventing excrement such as menstrual blood from flowing out to the outside of the transverse direction Y. As the side piece 5, a sheet with leakage resistance similar to the back sheet 3 can be used.

[0036] In the present invention, the "skin-opposing surface" refers to the surface of the absorbent article or its component (e.g., absorber 4) that faces the skin side of the wearer when the absorbent article is worn, that is, the outer surface on the side relatively close to the skin of the wearer. In addition, the "non-skin-opposing surface" refers to the outer surface of the absorbent article or its component that faces the side opposite to the skin side when the absorbent article is worn, that is, the side relatively far from the skin of the wearer. In addition, "when worn" here refers to the state of maintaining the normal appropriate wearing position, that is, the correct wearing position of the absorbent article.

[0037] like Figure 1 As shown, the sanitary napkin 1 has an excretion area M relative to the wearer's excretion area, a front area F located in front of the excretion area M in the longitudinal direction X (ventral side), and a rear area R located in the rear of the excretion area M in the longitudinal direction X (dorsal side).

[0038] In the present invention, "the area opposite to the excretion part" refers to an area in the absorbent configuration area of ​​the absorbent article (the area overlapping with the absorbent when viewed from above) that includes the excretion part opposite portion that is arranged opposite to the excretion part. The above-mentioned "excretion part" refers to the part where the body fluids (menstrual blood, urine, feces, sweat, etc.) of the wearer of the absorbent article are excreted, typically the vaginal opening, penis or anus, which varies depending on the purpose of the absorbent article, etc. The above-mentioned "excretion part opposite portion" refers to an area in the absorbent article that overlaps with the above-mentioned excretion part when viewed from above when worn. The above-mentioned excretion part opposite area can be, for example, the entire area in the absorbent configuration area of ​​the absorbent article that is at the same position in the longitudinal direction as the above-mentioned excretion part opposite portion (the area that overlaps with the projection image when the above-mentioned excretion part opposite portion is projected horizontally). In the case where the absorbent article is an absorbent article for women such as a sanitary napkin 1 and a panty liner, its excretion part opposite area refers to an area that is arranged opposite to the vaginal opening when worn.

[0039] The boundary between the front region F and the excretion region M (the front end in the longitudinal direction X of the excretion region M) is typically present at a position 10% to 40% away from the longitudinal front end 1F of the sanitary napkin 1 to the rear in the longitudinal direction X by the total length of the sanitary napkin 1 in the longitudinal direction X. In addition, the boundary between the rear region R and the excretion region M (the rear end in the longitudinal direction X of the excretion region M) is typically present at a position 10% to 40% away from the longitudinal rear end 1R of the sanitary napkin 1 to the front in the longitudinal direction X by the total length of the sanitary napkin 1 in the longitudinal direction X. The "full length in the longitudinal direction X of the sanitary napkin 1" referred to herein refers to the length of the longitudinal front end 1F and the longitudinal rear end 1R of the sanitary napkin 1 in the natural state (state without external force applied) along the longitudinal direction X.

[0040] The absorbent body 4 includes at least an absorbent core 40. In the present embodiment, the absorbent core 40 has a shape that is long in the longitudinal direction X in a plan view, and the longitudinal direction thereof coincides with the longitudinal direction X of the sanitary napkin 1.

[0041] The absorbent core 40 constitutes the main body of the absorbent body 4, and can absorb and retain body fluids by containing a water-absorbent material. Examples of the water-absorbent material include water-absorbent fibers and water-absorbent polymers, and one of them can be used alone or in combination of two or more. Examples of the water-absorbent fiber include natural fibers such as wood pulp and hydrophilic fibers such as hydrophilic synthetic fibers. Examples of the water-absorbent polymer include water-absorbent polymers that have been used in such absorbent bodies without particular limitation, and examples thereof include polymers or copolymers of acrylic acid or alkali metal salts of acrylic acid.

[0042] The absorbent core 40 may be a fiber accumulation type or a sheet type. The fiber accumulation type absorbent core typically has a structure in which an aggregate of fiber materials such as absorbent fibers is the main body, and absorbent polymer particles are carried on the aggregate as needed. The fiber accumulation type absorbent core can be manufactured in a conventional manner using a known fiber accumulation device having a rotating drum. On the other hand, the sheet type absorbent core typically has a structure in which absorbent polymer particles are fixed inside or on the surface of a fiber sheet, and is also referred to as an absorbent sheet. As the fiber sheet, for example, paper, nonwoven fabric, etc. can be used. The sheet type absorbent core is thinner and softer than the fiber accumulation type absorbent core. The sheet type absorbent core can, for example, have a structure in which absorbent polymer particles are arranged between two opposing fiber sheets.

[0043] In this embodiment, if Figure 2 As shown, the absorbent body 4 includes, in addition to the absorbent core 40, a liquid-permeable core sheet 41 covering the outer surface (skin-opposite side and non-skin-opposite side) of the absorbent core 40. The core sheet 41 is used for the purpose of improving the shape retention of the absorbent core 40, preventing the formation materials of the absorbent core 40 such as absorbent polymer particles from falling off, and is typically made of paper, permeable nonwoven fabric, etc. The core sheet 41 can be composed of only one sheet or a plurality of sheets. The absorbent core 40 and the core sheet 41 can also be joined by an adhesive such as a hot-melt adhesive.

[0044] In this embodiment, if Figure 2 As shown, the absorbent body 4 has a fiber block layer 42 mainly composed of a fiber block 11 containing non-absorbent fibers in the excretion relative region M. The fiber block layer 42 is covered by the core packing 41 together with the absorbent core 40. In addition, in the present embodiment, the fiber block layer 42 is arranged only in the entire region of the excretion relative region M, and the arrangement region of the fiber block layer 42 is the excretion relative region M. The non-arrangement region of the fiber block layer 42 in the absorbent body 4 (the portion located in the front region F and the rear region R of the absorbent body 4) has the absorbent core 40 but does not have the fiber block layer 42. Therefore, the arrangement region of the fiber block layer 42 is thicker and larger in volume than the non-arrangement region of the fiber block layer 42. Due to the difference in thickness of the absorbent body 4 caused by the presence or absence of the fiber block layer 42, the skin-facing side of the excretion relative region M, which is the arrangement region of the fiber block layer 42, is raised compared with the front region F and the rear region R, which are the non-arrangement regions of the fiber block layer 42, forming a so-called middle high portion.

[0045] The fiber block layer 42 is present in a region (region between narrowed portions) between a rear narrowed portion 62 and a front narrowed portion 61 described later in the longitudinal direction X. Due to the presence of the fiber block layer 42, the region between narrowed portions has higher compression recovery than a region adjacent to the region between narrowed portions in the longitudinal direction X. The fiber block layer 42 will be described in detail later.

[0046] like Figure 1 As shown, the sanitary napkin 1 has wing portions 6 extending outward from the outer edge (peripheral edge) of the absorbent body 4 and forming the outline of the sanitary napkin 1. The wing portions 6 are regions where the absorbent body 4 is not arranged.

[0047] In the present embodiment, the wing portion 6 is composed of components arranged in a manner that spans the outer edge of the absorbent body 4 inside and outside, and in the illustrated manner, is composed of one or more of the front sheet 2, the back sheet 3, and the side sheet 5. The multiple components constituting the wing portion 6 are bonded to each other by bonding means such as adhesives, heat-based or ultrasonic welding, etc. In the present embodiment, an edge seal portion 60 is formed by welding the outer edge portion of the wing portion 6 (the outer edge of the wing portion 6 and its vicinity) over the entire circumference.

[0048] The wing portion 6 includes: a pair of side wing portions 6S, 6S located on the outside of the transverse direction Y with respect to a pair of imaginary straight lines VL, VL passing through the outermost ends of the transverse direction Y of the absorbent body 4 and extending in the longitudinal direction X as a reference; and a front wing portion 6F located on the inside of the transverse direction Y than the reference and in the front region F; and a rear wing portion 6R located on the inside of the transverse direction Y than the reference and in the rear region R.

[0049] The “lateral outermost end of the absorber” is the outermost portion on one side and the other side of the absorber 4 in the lateral direction Y, and in the present embodiment, is a pair of side edges 4S, 4S of the absorber 4 along the longitudinal direction.

[0050] The side wing portion 6S is located outside the virtual straight line VL in the transverse direction Y, and the absorber 4 is required to be located inside the side wing portion 6S in the transverse direction Y. That is, the side wing portion of the present invention overlaps with the transverse projection image of the absorber.

[0051] Typically, a fixing portion (not shown) for fixing the sanitary napkin 1 to the wearer's clothing is disposed on the non-skin facing surface (non-skin facing surface of the back sheet 3) of the sanitary napkin 1. As the fixing portion, any fixing portion used in the prior art as a means for fixing such an absorbent article to clothing such as shorts can be used without particular limitation, and for example, an adhesive, a pressure-sensitive adhesive, etc. can be used.

[0052] The sanitary napkin 1 has the following outer shape of the rear region R.

[0053] First, the outer edges of the pair of side wings 6S, 6S have a pair of rear convex portions 65, 65 in the rear region R, and the pair of rear convex portions 65, 65 are located in front of the longitudinal rear end of the wing 6 in the longitudinal direction X and protrude outward from the peripheral portion in the transverse direction Y. The above-mentioned "longitudinal rear end of the wing 6" is the longitudinal rear end 1R of the sanitary napkin 1.

[0054] In addition, a portion of the outer edge of the wing 6 sandwiched between the longitudinal rear end 1R and the rear convex portion 65 has an inwardly convex curved portion 66 having a center of curvature on the outer side of the outer edge, and the inwardly convex curved portion 66 is a single curved shape consisting of curved lines that take the longitudinal rear end 1R and the rear convex portion 65 as starting points and extend from the two starting points 1R and 65 to a single convex top (maximum point) 66P located between the two starting points 1R and 65.

[0055] Furthermore, the top 66P of the inwardly convexly curved portion 66 (an imaginary straight line passing through the pair of left and right tops 66P, 66P and extending in the transverse direction Y) is located forward in the longitudinal direction X relative to the longitudinal rear end 4R of the absorbent body 4 .

[0056] The sanitary napkin 1 has excellent leakage-proof performance due to the outer shape of the rear region R, and is not easy to leak excrement. It is also softly twisted and deformed when the wearer walks, etc., and it is very difficult for the wearer to feel discomfort. Specifically, in the sanitary napkin 1, the outer edge of the side wing portion 6S has a rear convex portion 65 in the rear region R, and the outer edge of the side wing portion 6S, which is easy to become the starting point of deformation of the rear region R, has a single inward convex curved portion 66 between the rear convex portion 65 and the longitudinal rear end 1R. Therefore, when the wearer of the sanitary napkin 1 walks and generates an external force such as twisting in the rear region R, the rear convex portion 65 becomes the twisting starting point, and the inward convex curved portion 66 follows the external force and easily twists and deforms. The ease of deformation can be evaluated by the "torque value" measured by the following method as an indicator. The sanitary napkin 1 having the rear convex portion 65 and the single inward convex curved portion 66 connected thereto has a sufficiently small torque value, and it is not easy for the wearer to feel discomfort when twisting and deforming occurs due to the body movement of the wearer.

[0057] Generally speaking, if the rear region R is wide, it is difficult for the rear region R to deform in accordance with the movement of the body (especially the buttocks) of the wearer of the sanitary napkin 1, which may cause discomfort when wearing. In addition, generally speaking, the narrow width (the length of the side edge 4S of the absorbent body 4 and the outer edge of the side wing portion 6S in the horizontal direction Y) of the side wing portion 6S is prone to wrinkles, bends and other undesirable deformations that may cause discomfort when wearing. However, in the sanitary napkin 1, the top 66P of the inwardly convex curved portion 66 is located at a position forward of the longitudinal rear end 4R of the absorbent body 4 in the longitudinal direction X, so that the top 66P is arranged close to the absorbent body 4 with relatively high rigidity, so wrinkles and bends of the inwardly convex curved portion 66 are not easy to occur.

[0058] <Method for measuring torque value>

[0059] The absorbent article of the measurement object is used as a measurement sample as it is. Figure 42 shows a measurement method when a sanitary napkin 100 is used as a measurement sample. The basic structure of the sanitary napkin 100 is the same as that of the sanitary napkin 1 described above. Figure 4 As shown in (a), the two ends of the sanitary napkin 100 in the longitudinal direction X (length direction) are clamped between the upper and lower clamps 101 and 102 of a tension control torque tester (manufactured by IMADA Co., Ltd.), and the sanitary napkin 100 is fixed between the upper and lower clamps 101 and 102. Figure 4 (b) and Figure 4 As shown in (c), the upper clamp 101 is reciprocated 60° in the positive and reverse directions (forward and reverse) with the longitudinal direction X of the sanitary napkin 100 as the rotation axis, and the torsional moment value (60° torque value) applied to the sanitary napkin 100 is measured. Specifically, the reciprocating rotation is performed 10 times to obtain the maximum values ​​of the 10 torsional moment values ​​in the positive and reverse directions. The average values ​​of the above 10 maximum values ​​are respectively calculated for the positive and reverse directions, and the sum of the absolute values ​​of the two average values ​​is taken as the torque value (unit: Ncm) of the measured object. The measurement is performed on 5 measurement samples, and the average of the 5 measurements is calculated. In addition, the tension applied to the measurement sample during rotation is set to a range of 3 to 6N for measurement. During the measurement, the length between the clamps is set to 175mm when no tension is applied. The torque testing machine used is in accordance with JIS K7244-2. Figure 2 The testing machine described in.

[0060] From the viewpoint of further reliably exerting the effects caused by the outer shape of the above-mentioned rear region R, it is preferred that a pair of rear convex portions 65, 65 exist in the rearmost region when the sanitary napkin 1 is divided into three equal parts in the longitudinal direction X, and the length (width) of the rearmost region in the transverse direction Y is the longest between the pair of rear convex portions 65, 65. The above-mentioned rearmost region is composed of at least the rear region R, or includes the excretion portion facing region M and the rear region R.

[0061] From the viewpoint of further reliably achieving the effects caused by the outer shape of the rear region R, refer to Figure 3The angle θ formed by two imaginary straight lines V1 and V1 connecting the longitudinal rear end of the wing 6 and the top of a pair of rear convex parts 65 and 65 (the outermost end of the rear convex part 65 in the transverse direction Y) is preferably 40° or more, more preferably 45° or more, and further preferably 50° or more, and preferably 100° or less, more preferably 95° or less, and further preferably 90° or less. By adopting a structure having a rear convex part 65 and a single inward convex curved part 66 connected to the rear convex part 65, it is possible to achieve an improvement in wearing feeling due to a reduction in torque value, and by setting the angle θ within the above-mentioned preferred range, the length (width) of the transverse direction Y of the rear region R is more appropriate from the viewpoint of leakage prevention, and it is possible to more effectively prevent excrement from leaking out of the rear region R.

[0062] From the perspective of reducing the torque value to further improve the wearing feel, Figure 3 As shown, it is preferred that the outer edge of the longitudinal rear end portion of the wing portion 6 (the longitudinal rear end 1R of the sanitary napkin 1) has an outward convex curved portion 67 having a curvature center on the inner side of the outer edge, and the curvature radius thereof is smaller than that of the inward convex curved portion 66. That is, it is preferred that the outer edge of the longitudinal rear end portion of the wing portion 6 is the outward convex curved portion 67 that is convexly curved toward the outer side in the longitudinal direction X of the sanitary napkin 1, and the outward convex curved portion 67 has a smaller curvature radius and a sharper curvature (larger curvature) than the inward convex curved portion 66 connected thereto.

[0063] The ratio of the curvature radius Rb of the outwardly convexly curved portion 67 to the curvature radius Ra of the inwardly convexly curved portion 66 is preferably 0.05 or more, more preferably 0.1 or more, and is preferably 0.9 or less, more preferably 0.85 or less, when expressed as Rb / Ra, on the premise that Rb<Ra.

[0064] The curvature radius Rb of the outwardly convexly curved portion 67 is preferably 5 mm or more, more preferably 7 mm or more, provided that it is smaller than the curvature radius Ra of the inwardly convexly curved portion 66 , and is preferably 90 mm or less, more preferably 80 mm or less.

[0065] The curvature radius Ra of the inwardly convexly curved portion 66 is preferably greater than the curvature radius Rb of the outwardly convexly curved portion 67 and is preferably greater than 10 mm, more preferably greater than 15 mm, and is preferably less than 120 mm, more preferably less than 100 mm.

[0066] In this embodiment, if Figure 3As shown, the outer edge of the absorbent body 4 has a rear curved portion 47 connected to the longitudinal rear end 4R of the absorbent body 4 and extending along the inwardly curved portion 66 of the outer edge of the wing portion 6. The rear curved portion 47 has a center of curvature outside the outer edge of the absorbent body 4. By configuring the absorbent body 4 in the rear region R in this way, the softness of the outer edge of the rear region R of the sanitary napkin 1 and its vicinity (edge ​​portion) is improved, and as a result, the torque value can be further reduced and the wearing feeling can be further improved.

[0067] The curvature radius of the rear curved portion 47 and the curvature radius of the inwardly convexly curved portion 66 may be the same as or different from each other.

[0068] From the perspective of more reliably achieving the effect brought about by the rear curved portion 47, the ratio of the curvature radius of the rear curved portion 47 to the curvature radius of the inwardly convex curved portion 66, when expressed as the former / the latter, is preferably greater than 0.6, more preferably greater than 0.7, and is preferably less than 1.4, more preferably less than 1.3.

[0069] Reference Figure 5 , assuming that a triangle is formed with an imaginary straight line H1 connecting the longitudinal front end 66A and the longitudinal rear end 66B of the inward convex curved portion 66 as the base, and two imaginary straight lines H2 and H3 connecting the top (maximum point) 66P of the inward convex curved portion 66 with the front end 66A and the rear end 66B as the two sides, in the triangle, the angle (base angle) θ1 formed by the vertex of the front end 66A and the angle (base angle) θ2 formed by the vertex of the rear end 66B are preferably 3° or more and 35° or less, more preferably 5° or more and 25° or less. By making the angles θ1 and θ2 within the above ranges, the fit to the bulging area between the wearer's gluteal cleft and gluteal groove can be further improved, and the improvement of absorbency can be expected. In addition, when the angles θ1 and θ2 are 0°, it means that the top 66P of the convex curved portion 66 is located on the imaginary straight line H1 (the base of the above-mentioned triangle). When the angles θ1 and θ2 exceed 0°, it means that the imaginary straight lines H2 and H3 (the two sides other than the base of the above-mentioned triangle) are located closer to the absorber 4 side than the imaginary straight line H1 in a direction orthogonal to the imaginary straight line H1.

[0070] In this embodiment, if Figure 5 As shown, in the inwardly convex curved portion 66, the front side of the longitudinal direction X including the longitudinal front end 66A is located at the same position as the absorber 4 in the longitudinal direction X, and the remaining portion (including the rear side of the longitudinal direction X including the longitudinal rear end 66B) is located at a position further back than the absorber 4 in the longitudinal direction X, and a portion includes a portion overlapping with the absorber 4 in the longitudinal direction X.

[0071] In the present invention, the inwardly convex curved portion 66 may not include a portion overlapping with the absorber 4 in the longitudinal direction X, that is, the proportion of this portion in the inwardly convex curved portion 66 (hereinafter also referred to as "absorber overlapping portion occupancy rate") may also be zero, but from the viewpoint of reliably exerting the effect caused by the outer shape of the above-mentioned rear region R, it is preferred that the absorber overlapping portion occupancy rate is not zero as in the present embodiment, and it is more preferred that the absorber overlapping portion occupancy rate is high. Specifically, the absorber overlapping portion occupancy rate in the inwardly convex curved portion 66 is preferably 50% or more, and more preferably 70% or more.

[0072] Reference Figure 5 , the absorbent overlapping portion occupancy rate in the inwardly convex curved portion 66 is "the ratio of the length 66L1 of the portion overlapping with the absorbent body 4 in the longitudinal direction X to the length 66L of the inwardly convex curved portion 66 in the extending direction (i.e., the length of the imaginary straight line H1 connecting the longitudinal front end 66A and the longitudinal rear end 66B of the inwardly convex curved portion 66) in the extending direction". The above-mentioned length 66L1 is the length between the longitudinal front end 66A of the inwardly convex curved portion 66 and the point P1 on the imaginary straight line H1, and the point P1 is the intersection of the imaginary straight line H1 and the imaginary straight line H4 extending parallel to the transverse direction Y and passing through the longitudinal rear end 4R of the absorbent body 4.

[0073] Reference Figure 3 The ratio of the length L1 in the longitudinal direction X between the rear convex portion 65 and the longitudinal rear end of the wing portion 6 (the longitudinal rear end 1R of the sanitary napkin 1) and the length (width) L2 in the transverse direction Y of the region between the rear convex portion 65 and the longitudinal rear end of the wing portion 6 (the longitudinal rear end 1R of the sanitary napkin 1) in the wing portion 6 (the sanitary napkin 1) is preferably 0.5 or more, more preferably 0.6 or more, and preferably 1.3 or less, more preferably 1.2 or less. By making L2 / L1 within the above range, it is possible to obtain sufficient space for arranging the absorbent body 4 in the region of the sanitary napkin 1 located behind the rear convex portion 65 in the longitudinal direction X, and it is possible to expect further improvement in the leakage prevention property.

[0074] Reference Figure 3 The length (width) L3 of the wing portion 6 (sanitary napkin 1) in the transverse direction Y at the same position as the longitudinal rear end 4R of the absorbent body 4 in the longitudinal direction X is preferably 45 mm or more, more preferably 50 mm or more, and preferably 90 mm or less, more preferably 80 mm or less. By making the length L3 within the above range, the area of ​​the longitudinal rear end 4R of the absorbent body 4 and its vicinity can be made relatively large, and the improvement of the leakage prevention can be expected.

[0075] In this embodiment, if Figure 1 and Figure 3As shown, the outer edge of the side wing portion 6S has a rear narrowing portion 62 located in front of the rear convex portion 65 in the longitudinal direction X and connected to the rear convex portion 65. With this structure, the torque value of the sanitary napkin 1 is further reduced, and even if the wearer's body is more active, it is not easy for the wearer to feel uncomfortable. From the perspective of more reliably achieving this effect, the rear narrowing portion 62 is preferably located in the rear region R and adjacent to the rear convex portion 65 as shown in the figure.

[0076] In addition, in this embodiment, if Figure 1 As shown, the outer edge of the side wing portion 6S has a front narrowed portion 61 in the front region F. With this structure, the torque value of the sanitary napkin 1 is further reduced, and the wearer is less likely to feel discomfort even if the wearer's body moves actively.

[0077] The two narrowing portions 61 and 62 are further described. In this embodiment, Figure 1 As shown, the outer edge of the side wing portion 6S, more specifically, the side edge of the side wing portion 6S along the longitudinal direction X, has a front narrowing portion 61 located in the front region F and a rear narrowing portion 62 located in the rear region R, and the portion sandwiched by the two narrowing portions 61 and 62 (the region between the narrowing portions described later) has a curved portion 63 convex to the outside in the lateral direction Y. The curved portion 63 extends over the entire length of the longitudinal direction X of the excretion portion relative region M.

[0078] There is no inflection point in the portion of the outer edge of the side wing portion 6S sandwiched by the two narrowed portions 61, 62. Both narrowed portions 61, 62 are bent inwardly in the transverse direction Y and are formed by a curve. In the present invention, either or both of the two narrowed portions 61, 62 may be bent inwardly in the transverse direction Y and formed by a straight line.

[0079] In addition, in this embodiment, if Figure 1 As shown, the outer edge of the wing portion 6 (side wing portion 6S, front wing portion 6F) has a front convex portion 64, which is located at a position forward of the front narrowed portion 61 in the longitudinal direction X and is connected to the front narrowed portion 61, and protrudes in a direction away from the absorbent body 4. The front convex portion 64, like the rear convex portion 65, protrudes outward in the transverse direction Y than the peripheral portion.

[0080] In the present embodiment, the sanitary napkin 1 is a pad-type absorbent article. In the present utility model, a "pad-type absorbent article" refers to an absorbent article without a fin portion. As described above, the "fin portion" is a portion that is manually folded toward the non-skin-opposite side of the crotch using fingers when the absorbent article is fixed to the skin-opposite side of the crotch of clothing such as shorts. Typically, taking the sanitary napkin 1 as an example, the portion of the side wing portion 6S located in the excretion-opposite area M is a portion that extends to the outside of the horizontal direction Y to a greater extent than the peripheral portion. The sanitary napkin 1 does not have a portion that is manually folded toward the non-skin-opposite side of clothing by using fingers when wearing it, as with the fin portion.

[0081] In addition, in the sanitary napkin 1, if Figure 1 As shown, a portion of the outer edge of the side wing portion 6S has a curved portion 63 that protrudes outward in the transverse direction Y and extends outward in the transverse direction Y more than the peripheral portion, but the side wing portion 6S is not a portion that is folded toward the non-skin opposite side of the clothing by manual operation using fingers when the sanitary napkin 1 is fixed to the clothing like the fin portion, and can be clearly distinguished from the fin portion.

[0082] In the sanitary napkin 1, the distance G1 (see Figure 1 ) is typically about 35 mm at most. In contrast, in absorbent articles having fins, from the perspective of facilitating the manual bending operation of the fins using fingers, the lateral length of the fins, i.e., the distance between the top end of the fins (lateral outermost end) and the absorbent body, usually significantly exceeds the typical maximum value of 35 mm of the above-mentioned distance G1.

[0083] The sanitary napkin 1 is a pad-type absorbent article without fins, and thus eliminates the complexity of the wearing operation, which is a problem unique to absorbent articles with fins, and can be worn simply. That is, when the sanitary napkin 1 is worn on the crotch of the wearer, usually, first, the shorts are passed through the legs of the wearer, and before the shorts are made to fit tightly against the crotch, the sanitary napkin 1 is fixed to the skin-opposite surface (inner surface) of the crotch of the shorts via the fixing portion (not shown) of the sanitary napkin 1, and then the shorts are pulled toward the crotch and the sanitary napkin 1 is worn on the crotch. Figure 6, the sanitary napkin 1 is shown in a state of being worn on the crotch of the wearer, the sanitary napkin 1 is fixed to the skin-opposing surface of the crotch 21 of the shorts 20 via the above-mentioned fixing portion, and a part of the side wing 6S (curved portion 63 and its vicinity) is bent along the side edge of the crotch 21 to the side opposite to the crotch side, and is arranged along the wearer's thigh 30. The bent portion of the side wing 6S in the sanitary napkin 1 in the worn state has the same function as the fin portion in the sanitary napkin for physiological use in the prior art, and can prevent the sanitary napkin 1 from being displaced from the appropriate position during wearing, improve the fit of the sanitary napkin 1 to the body of the wearer, and prevent the leakage of excrement, etc. However, in order to form the bent state like this, it is not necessary to perform an artificial bending operation using fingers as required for the fin portion. That is, when the sanitary napkin 1 is fixed to the skin-opposing surface of the crotch 21 of the shorts 20 which has passed through the wearer's legs 30, 30 via the above-mentioned fixing portion, the portion (the portion with the outer edge being the curved portion 63) sandwiched by the front narrowed portion 61 and the rear narrowed portion 62 of the pair of side wings 6S, 6S respectively extends from the two side edges of the crotch 21. If the shorts 20 are pulled toward the crotch of the wearer in this state, the extended portions of the side wings 6S extending from the crotch 21 are naturally bent along the side edges of the crotch 21 in the direction opposite to the direction in which the shorts 20 are pulled toward the wearer. When the sanitary napkin 1 is in contact with the crotch, as shown in FIG. Figure 6 As shown, the extension portion is in a state along the leg (thigh) 30 of the wearer.

[0084] As described above, the extended portion of the side wing 6S from the crotch 21 can be naturally bent along the side edge of the crotch 21 by only pulling the shorts 20 toward the crotch side, without the need for manual bending operation using fingers. This is largely due to the effect of the two narrowed portions 61 and 62 provided at the outer edge of the side wing 6S. ​​That is, at the outer edge of the side wing 6S, the front narrowed portion 61 and the rear narrowed portion 62 are separated and arranged with the curved portion 63 therebetween, so that the curved portion 63 of the side wing 6S and its vicinity are formed to be easily deformed when subjected to external force. Therefore, when the sanitary napkin 1 is fixed to the crotch 21 at an appropriate fixing position, as long as the curved portion 63 and its vicinity are formed to be in a state of extending from the side edge of the crotch 21, the curved portion 63 and its vicinity extending from the side edge of the crotch 21 can be easily deformed by the external force acting through the wearer's legs (thighs) by only pulling the shorts 20 toward the crotch side.

[0085] From the perspective of more reliably exerting the easy-to-wear effect of the above-mentioned sanitary napkin 1, it is preferred that the above-mentioned fixing portion (a component for fixing the sanitary napkin 1 to the wearer's clothing) is arranged in an area overlapping with the absorbent body 4 when viewed from above, rather than in the wing portion 6 (side wing portion 6S).

[0086] From the viewpoint of more reliably exerting the effects of the wing portions 6, the dimensions of the various parts of the sanitary napkin 1 are preferably set as follows.

[0087] The front narrowed portion 61 is preferably arranged at a position preferably more than 40 mm, more preferably more than 50 mm, and preferably within 150 mm, more preferably within 140 mm, from the longitudinal front end 1F of the sanitary napkin 1 (the longitudinal front end of the wing 6) to the rear in the longitudinal direction X.

[0088] The rear narrowed portion 62 is preferably arranged at a position preferably more than 100 mm, more preferably more than 120 mm, and preferably within 350 mm, more preferably within 330 mm, in front of the longitudinal rear end 1R of the sanitary napkin 1 (the longitudinal rear end of the wing 6) in the longitudinal direction X.

[0089] The distance G2 between the front narrowing portion 61 and the rear narrowing portion 62 in the longitudinal direction X (see Figure 1 ) is preferably greater than 40 mm, more preferably greater than 60 mm, and is preferably less than 250 mm, more preferably less than 230 mm.

[0090] The maximum length (maximum width) of the sanitary napkin 1 in the transverse direction Y is preferably 60 mm or more, more preferably 80 mm or more, and preferably 200 mm or less, more preferably 180 mm or less. The portion of the sanitary napkin 1 having the maximum width is typically present in the excretion portion opposite region M, and in the illustrated embodiment, is the portion where the convex top of the curved portion 63 of the side wing portion 6S is present.

[0091] The total length of the sanitary napkin 1 in the longitudinal direction X is preferably 100 mm or more, more preferably 140 mm or more, and is preferably 450 mm or less, more preferably 420 mm or less.

[0092] The gap G3 between the top 66P of the inwardly convexly curved portion 66 and the absorbent body 4 (see Figure 1 ), from the viewpoint of alleviating the excessive rigidity of the absorbent body 4, making it easier to exert the effect of the outer shape of the above-mentioned characteristic rear region R, and ensuring sufficient absorption capacity, it is preferably greater than 4 mm, more preferably greater than 5 mm, and is preferably less than 30 mm, more preferably less than 20 mm.

[0093] In this embodiment, refer to Figure 1In the area (absorbent body configuration area) overlapping with the absorbent body 4 when viewed from above, the compression recovery of the area between the narrowed parts located between the rear narrowed part 62 and the front narrowed part 61 in the longitudinal direction X is higher than the compression recovery of the area adjacent to the narrowed parts in the longitudinal direction X. The above-mentioned area between the contracted parts with high compression recovery is excellent in cushioning, deforms well in response to external force, and can quickly return to its original state when the external force is released. The above-mentioned area between the narrowed parts exists throughout the entire length of the excretion part relative area M in the longitudinal direction X, so the excretion part relative area M is an area with relatively high compression recovery. Through this structure, the fit of the excretion part relative area M to the wearer's body is improved, the overall fit and followability of the sanitary napkin 1 to the body are improved, and it can be expected that the leakage prevention and wearing feeling will be further improved.

[0094] The above-mentioned "compression recovery" can be evaluated using compression work (hereinafter also referred to as "WC") and recovery work (hereinafter also referred to as "WC'") as indicators. WC is an indicator of the cushioning of the measured object. Therefore, the larger the value of WC, the better the cushioning of the measured object, and therefore the compression recovery is evaluated to be better. WC' is an indicator of the recovery (compression recovery) of the measured object when the external force is removed after the measured object is compressed by an external force. The larger the value of WC', the better the compression recovery of the measured object is evaluated to be. WC and WC' are measured by the following methods respectively.

[0095] <Method for measuring compression work (WC) and recovery work (WC')>

[0096] It is generally known that WC and WC' as the measurement object can be expressed by the measurement value measured by KES (Kawabata Evaluation System) manufactured by Kato Tech Co., Ltd. (reference: Standardization and Analysis of Hand Feel Evaluation (Second Edition), author Kawabata Yoshio, published on July 10, 1975). Specifically, WC and WC' can be measured using the compression tester KES-G5 manufactured by Kato Tech Co., Ltd. The measurement procedure is as follows.

[0097] First, install the sample on the test bench of the compression test device. The sample is, for example, an absorbent article such as sanitary napkin 1 or a component thereof (such as absorbent body 4). The sample is in a dry state and has a top view quadrilateral shape of 5 mm in length and 5 mm in width. In the case where the dry sample is an absorbent body or an absorbent article including the absorbent body, the absorbent body is unused, has not absorbed any liquid, and is in a dry state. Next, place the sample on a surface having an area of ​​2 cm 2The sample is compressed between the circular flat steel plates. The compressed part is the non-depressed part of the sample, that is, the part that has not been compressed and retains the original style of the sample. The compression speed is 0.2cm / sec, and the maximum compression load is 2450mN / cm 2 , SENS is 10, DEF is 20. The recovery process is also measured at the same speed. WC is expressed by the following formula (1), and WC' is expressed by the following formula (2), and the units of each are "mN·cm / cm 2 In the following formula, T m Indicates 2450mN / cm 2 (4.9kPa) load, T O Indicates 4.902mN / cm 2 (49Pa) The thickness when the load is applied. In addition, Pa in the following formula (1) and Pb in the following formula (2) respectively represent the measured load (mN / cm 2 ), measured load during thickness recovery process (mN / cm 2 ).

[0098] [Formula 1]

[0099]

[0100] [Formula 2]

[0101]

[0102] In addition, WC' is not displayed in the measurement result screen of the above-mentioned KES-G5. In the measurement result screen, WC and the compression recovery rate and / or compression rebound resilience (hereinafter also referred to as "RC") calculated based on WC' are displayed. In such a case, WC' is calculated according to the following formula using the parameters (WC, RC) displayed in the test device.

[0103] [Formula 3]

[0104] WC′=RC×WC÷100

[0105] The ratio of the WC of the narrowed area to the WC of the front area (e.g., front area F) or rear area (e.g., rear area R) in the longitudinal direction X is preferably 1.5 or more, more preferably 1.7 or more, when expressed as the former / the latter, assuming that the former is greater than the latter.

[0106] The WC of the region between the constrictions is preferably 100 mN·cm / cm 2 More preferably, 120 mN·cm / cm 2The upper limit of the WC in the narrowed region is not particularly limited, but is preferably 300 mN·cm / cm from the viewpoint of reducing the thickness of the absorbent article in an individually packaged state. 2 Below, more preferably 280 mN·cm / cm 2 the following.

[0107] The ratio of WC' in the narrowed area to the WC' in the front area (e.g., front area F) or rear area (e.g., rear area R) in the longitudinal direction X is preferably 1.5 or more, more preferably 1.7 or more, when expressed as former / latter, assuming that the former is greater than the latter.

[0108] The WC' in the narrowed area is preferably 100 mN·cm / cm 2 More preferably, 120 mN·cm / cm 2 The upper limit of WC' in the narrowed region is not particularly limited, but is preferably 300 mN·cm / cm from the viewpoint of reducing the thickness of the absorbent article in an individually packaged state. 2 Below, more preferably 280 mN·cm / cm 2 the following.

[0109] The difference in the compression recovery of the above-mentioned sanitary napkin 1 (absorbent body 4) is caused by the difference in the presence or absence of the fiber block layer 42. That is, the above-mentioned narrowed area (excretion area relative area M) contains the fiber block layer 42, and therefore has a higher compression recovery than other areas that do not contain the fiber block layer 42.

[0110] like Figure 2 As shown, the fiber block layer 42 is mainly composed of fiber blocks 11 containing non-absorbent fibers. Here, "mainly composed of fiber blocks" means that the fiber blocks 11 account for 90% by mass or more, preferably 95% by mass or more, and more preferably 100% by mass of all the fibers constituting the fiber block layer 42. The fiber block 11 is a fiber assembly formed by a plurality of non-absorbent fibers gathered in a block shape and integrated, and exists in the absorbent body 4 (fiber block layer 42) in a state of maintaining its shape. The fiber block 11 mainly contributes to the improvement of the softness, cushioning, compression recovery, and shape retention of the absorbent body 4 due to its fiber assembly shape.

[0111] As the non-absorbent fiber constituting the fiber mass 11, it is preferable to use a fiber (non-absorbent fiber) having a lower water absorption than the absorbent fiber such as cellulose fiber used as the absorbent material in the absorbent core 40, and a specific example thereof is a synthetic fiber mainly composed of a thermoplastic resin. Since the fiber mass 11 is constituted by including the non-absorbent fiber, even when the fiber mass 11 comes into contact with body fluids, the characteristics such as softness of the fiber mass 11 can be fully exhibited.

[0112] The shape of the fiber block 11 is not particularly limited, and may be an irregular shape, for example, a fiber block of a regular shape such as a sheet obtained by cutting a synthetic fiber sheet into a certain size may be used. As such a fiber block of a regular shape, for example, the fiber blocks described in Japanese Patent Publication No. 2019-063469, Japanese Patent Publication No. 2019-098157, and Japanese Patent Publication No. 2020-188918 can be appropriately used, and specifically, a fiber block having two opposing basic surfaces and a skeleton surface connecting the two basic surfaces can be appropriately used.

[0113] The fiber block layer 42 is a region where the fiber blocks 11 are present over the entire length of the absorbent body 4 in the transverse direction Y. The fiber block layer 42 may be composed of only the fiber blocks 11, or may contain a water-absorbent material in addition to the fiber blocks 11. The fiber block layer 42 containing the water-absorbent material can absorb and retain body fluids, and can improve the absorption performance of the absorbent body 4. As the water-absorbent material used in the fiber block layer 42, any material that can be used in the absorbent core 40 can be used without particular limitation.

[0114] In this embodiment, if Figure 2 As shown, the fiber block layer 42 includes the fiber blocks 11. Typically, the fiber block layer 42 only includes the fiber blocks 11. In the fiber block layer 42, the fiber blocks 11 are preferably intertwined with each other. By constituting the fiber block layer 42 in this way, the shape retention of the fiber block layer 42 is improved, and the absorbent body 4 having the fiber block layer 42 can be properly deformed with good tracking performance relative to the external forces received from all directions when worn, thereby becoming an absorbent body 4 with excellent softness, cushioning, and compression recovery. The sanitary napkin 1 having such an absorbent body 4 is easy to deform and recover relative to external forces, is not easy to wrinkle, and has excellent fit relative to the wearer's body. In addition, in the fiber block layer 42 and the absorbent core 40 arranged overlapping therewith, it is more preferred that the fiber blocks 11 of the former are intertwined with the water-absorbent fibers of the latter at the interface of the former.

[0115] The "entanglement" mentioned above includes the following two forms: (i) a form in which the entangled objects (fiber blocks or fiber blocks and absorbent fibers) are not fused to each other, and their bonding state is maintained by the entanglement of the constituent fibers of the fiber blocks; and (ii) a form in which the fiber blocks or the fiber blocks and absorbent fibers are not bonded to each other in the natural state of the absorbent article (absorbent body) (a state in which no external force is applied), but when an external force is applied to the absorbent article (absorbent body), the fiber blocks or the fiber blocks and absorbent fibers can be bonded to each other by the entanglement of the constituent fibers.

[0116] In this embodiment, in the discharge portion relative area M, as shown in FIG. Figure 2As shown, the skin-opposite side of the absorbent body 4 is composed of an absorbent core 40 mainly composed of absorbent fibers 12 and absorbent polymer particles 13, and substantially does not contain fiber blocks 11. In contrast, the non-skin-opposite side of the absorbent body 4 is composed of a fiber block layer 42 mainly composed of fiber blocks 11.

[0117] More specifically, in the present embodiment, in the absorbent body 4 in the excretion portion relative region M, the fiber mass occupancy rate calculated by the following formula (A) is lower on the skin-opposing surface side than on the non-skin-opposing surface side. That is, in the present embodiment, the fiber mass 11 in the absorbent body 4 is biased toward the non-skin-opposing surface side. More specifically, in the excretion portion relative region M, the absorbent fibers 12 are more likely to exist on the skin-opposing surface side of the absorbent body 4, and the content of the fiber mass 11 may be zero, whereas the fiber mass 11 is more likely to exist on the non-skin-opposing surface side of the absorbent body 4, and the content of the absorbent fibers 12 may be zero.

[0118] In addition, the "skin-opposing side of the absorbent body" mentioned here refers to the side including the skin-opposing side when the absorbent body 4 is divided into two equal parts in the thickness direction (the side relatively close to the wearer's skin), and the "non-skin-opposing side of the absorbent body" refers to the opposite side (the side relatively far from the wearer's skin).

[0119] As described above, in the absorbent body 4 in the excretion portion relative area M, the above-mentioned size relationship "skin-opposing side of the absorbent body 4 < non-skin-opposing side of the absorbent body 4" holds true with respect to the fiber block occupancy rate. As a result, through the action of the water-absorbent fibers biased toward the skin-opposing side of the absorbent body 4, the force (capillary force) of introducing body fluids into the absorbent body 4 is improved, thereby improving the liquid absorption. Furthermore, through the action of the fiber blocks 11 biased toward the non-skin-opposing side of the absorbent body 4, the cushioning properties of the absorbent body 4 can be improved.

[0120] The fiber mass occupancy rate is the content of each of the fiber mass and the water-absorbent material present in a predetermined measurement target portion of the absorbent body measured by mass, and the measured fiber mass content is divided by the total value of the fiber mass and the water-absorbent material content, and the result is expressed as a percentage. As described above, the water-absorbent material is typically a water-absorbent fiber and / or a water-absorbent polymer.

[0121] Fiber mass occupancy rate (mass %) = {mass content of fiber mass / (mass content of water-absorbing material+mass content of fiber mass)}×100 (A)

[0122] As mentioned above, although this invention was demonstrated based on the preferred embodiment, this invention is not limited at all to the said embodiment, It can change suitably within the range which does not deviate from the summary of this invention.

[0123] For example, a recessed portion formed by the front sheet 2 and the absorbent body 4 forming the skin-facing surface being integrally recessed toward the non-skin-facing surface (back sheet 3) may be formed on the skin-facing surface of the sanitary napkin 1. In this case, the recessed portion may also include a linear longitudinal recessed portion extending in the longitudinal direction X and / or a linear transverse recessed portion extending in the transverse direction Y.

[0124] The absorbent article of the present invention includes articles for absorbing body fluids (menstrual blood, urine, soft stool, sweat, etc.) discharged from the human body, and is not limited to the above-mentioned sanitary napkin.

[0125] The following additional remarks are further disclosed regarding the above-mentioned embodiments of the present invention.

[0126] <1>

[0127] An absorbent article, comprising an absorbent body capable of absorbing and retaining body fluids, and having a longitudinal direction corresponding to the front-back direction of a wearer and a transverse direction orthogonal to the longitudinal direction, and comprising an excretion portion-opposing region arranged opposite to the excretion portion of the wearer when worn, a front region arranged at a position forward of the excretion portion-opposing region in the longitudinal direction, and a rear region arranged at a position rearward of the excretion portion-opposing region in the longitudinal direction,

[0128] In the absorbent article,

[0129] The absorbent article has a wing portion extending outward from the outer edge of the absorbent body and forming the outline of the absorbent article, the wing portion having a pair of side wing portions located on the outside of the transverse direction relative to a pair of imaginary straight lines extending in the longitudinal direction and passing through the outermost end of the transverse direction of the absorbent body,

[0130] The absorbent body is located on the inner side of the side wing portion in the lateral direction.

[0131] The outer edges of the pair of side wings have a pair of rear convex portions in the rear region, which are located forward of the longitudinal direction relative to the longitudinal rear ends of the wings and protrude outward in the lateral direction relative to the peripheral portions.

[0132] A portion of the outer edge of the wing portion sandwiched between the longitudinal rear end of the wing portion and the rear convex portion has an inwardly convex curved portion having a center of curvature outside the outer edge,

[0133] The inward convex curved portion is a single curved shape consisting of curved lines extending from the longitudinal rear end of the wing and the rear convex portion as starting points to a single convex top located between the two starting points, and the top is located at a position forward of the longitudinal direction relative to the longitudinal rear end of the absorbent body.

[0134] <2>

[0135] The absorbent article as described in <1>, wherein the outer edge of the longitudinal rear end portion of the wing portion has an outwardly convex curved portion having a center of curvature inside the outer edge, and the curvature radius of the outwardly convex curved portion is smaller than that of the inwardly convex curved portion.

[0136] <3>

[0137] The absorbent article as described in <1> or <2>, wherein the outer edge of the absorbent body has a rearward curved portion connected to the rear end in the longitudinal direction of the absorbent body and extending along the inwardly curved portion of the outer edge of the wing portion.

[0138] <4>

[0139] The absorbent article as described in any one of <1> to <3>, wherein the outer edge of the side wing portion has a rear narrowing portion that is located forward of the rear convex portion in the longitudinal direction and connected to the rear convex portion and is curved inward in the transverse direction.

[0140] <5>

[0141] The absorbent article as described in <4>, wherein the outer edge of the side flap portion has a front narrowed portion that is curved inward in the lateral direction in the front region.

[0142] <6>

[0143] According to the absorbent article described in <5>, in the area overlapping with the absorbent body when viewed from above, the compression recovery property of the area between the narrowed portions located between the rear narrowed portion and the front narrowed portion in the longitudinal direction is higher than the compression recovery property of the area adjacent to the area between the narrowed portions in the longitudinal direction.

[0144] <7>

[0145] The absorbent article as described in <6>, wherein the ratio of the compression work WC of the region between the narrowed portions to the compression work WC of the region in front or behind the longitudinal direction thereof is 1.5 or more, more preferably 1.7 or more when expressed as the former / the latter.

[0146] <8>

[0147] The absorbent article as described in any one of <5> to <7>, wherein the absorbent body has a fiber block layer, which includes absorbent fibers and fiber blocks containing non-absorbent fibers, the fiber blocks are intertwined with each other, or the fiber blocks are intertwined with the absorbent fibers, and the fiber block layer is mainly composed of the fiber blocks.

[0148] The fiber block layer is present in the inter-narrowing region between the rear narrowing and the front narrowing in the longitudinal direction.

[0149] <9>

[0150] An absorbent article as described in any one of <1> to <8>, wherein a pair of the rear convex portions exist in the rearmost region when the absorbent article is divided into three equal parts in the longitudinal direction, and the lateral length of the rearmost region is the longest between the pair of rear convex portions.

[0151] <10>

[0152] The absorbent article according to any one of <1> to <9>, wherein an angle formed by two imaginary straight lines connecting the longitudinal rear end of the wing portion and the tops of the pair of rear convex portions is 40° to 100°.

[0153] <11>

[0154] An absorbent article as described in any one of <1> to <10>, wherein the ratio of the longitudinal length L1 between the rear convex portion and the longitudinal rear end of the wing portion to the transverse length L2 of the area between the rear convex portion and the longitudinal rear end of the wing portion, when expressed as L2 / L1, is preferably greater than 0.5, more preferably greater than 0.6, and is preferably less than 1.3, more preferably less than 1.2.

[0155] <12>

[0156] An absorbent article as described in any one of <1> to <11>, wherein the lateral length (width) (L3) of the wing portion at the same position as the longitudinal rear end of the absorbent body in the longitudinal direction is preferably greater than 45 mm, more preferably greater than 50 mm, and is preferably less than 90 mm, more preferably less than 80 mm.

[0157] <13>

[0158] An absorbent article as described in any one of <1> to <12>, wherein, when assuming a triangle with an imaginary straight line connecting the longitudinal front end and the longitudinal rear end of the inwardly convex curved portion as the base, and two imaginary straight lines connecting the top (maximum point) of the inwardly convex curved portion and the longitudinal front end and the longitudinal rear end as the two sides, the angle (θ1) formed by the vertices of the longitudinal front end and the angle (θ2) formed by the vertices of the longitudinal rear end in the triangle are respectively greater than 3° and less than 35°, and preferably greater than 5° and less than 25°.

[0159] <14>

[0160] An absorbent article as described in any one of <1> to <13>, wherein the inwardly convex curved portion includes a portion overlapping with the absorbent body in the longitudinal direction, and the proportion of this portion in the inwardly convex curved portion (occupancy rate of the absorbent body overlapping portion) is preferably greater than 50%, more preferably greater than 70%.

[0161] <15>

[0162] The absorbent article as described in any one of <1> to <7> and <9> to <14>, wherein the absorbent body includes absorbent fibers and fiber masses containing non-absorbent fibers, and the fiber masses are entangled with each other or the fiber masses are entangled with the absorbent fibers.

[0163] <16>

[0164] The absorbent article according to <15>, wherein the absorbent body includes a fiber block layer mainly composed of the fiber block.

[0165] <17>

[0166] An absorbent article as described in <15> or <16>, wherein, in the area relative to the excretion part, the skin-opposing side of the absorbent body is formed by an absorbent core mainly composed of absorbent fibers and absorbent polymer particles, and the non-skin-opposing side of the absorbent body is formed by the fiber block layer.

[0167] <18>

[0168] The absorbent article according to any one of <15> to <17>, wherein the fiber block layer is a region where the fiber blocks exist over the entire length of the absorbent body in the lateral direction.

[0169] <19>

[0170] The absorbent article according to any one of <15> to <18>, wherein the fiber mass in the fiber mass layer accounts for 100% by mass of the fiber mass.

[0171] <20>

[0172] The absorbent article according to any one of <1> to <19>, wherein the absorbent article is a sanitary napkin.

[0173] [Experimental example]

[0174] Hereinafter, the present invention will be described in more detail by using experimental examples, but the present invention is not limited to the experimental examples.

[0175] [Experimental Example 1]

[0176] Make the basic structure and Figure 1 The sanitary napkin 1 shown is the same sanitary napkin. Details of the main components of the sanitary napkin of Experimental Example 1 are as follows.

[0177] · Front sheet: hot air non-woven fabric (weight 28g / m 2 ).

[0178] Back sheet: Polyethylene resin film (weight 38g / m 2 ).

[0179] Side panels: Spunbond nonwoven fabric (weight 20g / m 2 ).

[0180] Absorbent core: Used in absorbent fibers (bleached kraft pulp from coniferous trees, weight 200-210 g / m 2 ) is loaded with water-absorbent polymer particles (50 g / m 2 ) of the fiber accumulation type.

[0181] ·Wrap the chip: Use thin tissue paper (weight 16g / m 2 ).

[0182] Fiber block layer: Use fiber block 200g / m 2 With absorbent fiber (coniferous bleached kraft pulp) 210g / m 2 As the fiber mass, a fiber mass produced by the following method was used.

[0183] (Method for producing fiber block)

[0184] The fiber block was manufactured according to the method described in Japanese Patent Publication No. 2019-063469. Specifically, the raw fiber sheet was cut into small cubes (dice-shaped) to manufacture a rectangular parallelepiped fiber block (a fiber block having two opposing basic faces and a skeleton face connecting the two basic faces). As the raw fiber sheet, a hydrophobic thermoplastic fiber (non-absorbent fiber, fiber diameter 18 μm) composed of polyethylene resin and polyethylene terephthalate resin was used as the constituent fiber with a gram weight of 25 g / m 2 The fiber block has a short side of 3.9 mm, a long side of 5 mm, and a thickness of 0.6 mm.

[0185] [Experimental Example 2 to Experimental Example 6]

[0186] Production Figure 7 , Figure 8 The sanitary napkins 1A to 1E are shown. The sanitary napkins 1A to 1E are basically configured in the same manner as the sanitary napkin 1 (the sanitary napkin of Experimental Example 1) described above except for the configuration described below. Figure 7 , Figure 8 In the present invention, the same reference numerals as those in sanitary napkin 1 are given to the same components in sanitary napkins 1A to 1E as those in sanitary napkin 1. The description of sanitary napkin 1 described above can be appropriately applied to the components not particularly described in sanitary napkins 1A to 1E.

[0187] Figure 7 In the sanitary napkin 1A shown in (a), the curvature radii Ra and Rb of the inwardly convex curved portion 66 and the outwardly convexly curved portion 67 of the rear region R and their ratio Rb / Ra are different from those of the sanitary napkin 1. In addition, the outer shapes of the front region F and the portion close to the front region F in the excretion relative region M are different from those of the sanitary napkin 1. The rear region R of the sanitary napkin 1A is the same as the rear region R of the sanitary napkin 1. Compared with the sanitary napkin 1, the sanitary napkin 1A has a more abrupt curvature of the longitudinal front end of the wing 6 (the longitudinal front end 1F of the sanitary napkin 1), and the separation length in the longitudinal direction X between the front narrowed portion 61 and the longitudinal front end 1F of the sanitary napkin 1 is longer.

[0188] Figure 7 The sanitary napkin 1B shown in (b) is different from the sanitary napkin 1 in addition to the curvature radii Ra and Rb of the inwardly convexly curved portion 66 and the outwardly convexly curved portion 67 of the rear region R and their ratio Rb / Ra, and also in the angle θ.

[0189] Figure 8 The sanitary napkin 1C shown in (a) and Figure 8 The sanitary napkin 1D shown in (b) is significantly different from the overall outer shape of the sanitary napkin 1, the main differences being that the angle θ exceeds 100° and the top 66P of the convex curved portion 66 is located further back in the longitudinal direction X than the longitudinal rear end 4R of the absorbent body 4.

[0190] Figure 8 The sanitary napkin 1E shown in (c) is different from the sanitary napkin 1 in that the portion of the outer edge of the wing portion 6 sandwiched between the longitudinal rear end 1R and the rear convex portion 65 does not have the inwardly convex curved portion 66 having the center of curvature outside the outer edge. In addition, the outer edge of the absorbent body 4 does not have the rear curved portion 47 extending along the inwardly convex curved portion 66 of the outer edge of the wing portion 6 (see Figure 3 )This is also different from sanitary napkin 1.

[0191] The torque value of the sanitary napkin of each experimental example was measured by the above method. In addition, the "restoration work WC' of the fiber block layer arrangement area / restoration work WC' of the area adjacent to the area in the longitudinal direction" was calculated. The measurement of the restoration work WC' was carried out according to the above method. The "area adjacent to the fiber block layer arrangement area in the longitudinal direction" mentioned here refers to the area corresponding to the rear area R in the sanitary napkin 1. The results are shown in the following Table 1.

[0192] [Table 1]

[0193]

[0194] Possibility of industrial application

[0195] According to the present invention, an absorbent article having excellent leakage prevention properties and wearing comfort is provided.

Claims

1. An absorbent article, comprising an absorbent body capable of absorbing and retaining body fluids, and having a longitudinal direction corresponding to the front-back direction of a wearer and a transverse direction orthogonal to the longitudinal direction, and comprising an excretion portion-opposing region arranged opposite to the excretion portion of the wearer when worn, a front region arranged at a position forward of the excretion portion-opposing region in the longitudinal direction, and a rear region arranged at a position rearward of the excretion portion-opposing region in the longitudinal direction, The absorbent article is characterized in that: The absorbent article has a wing portion extending outward from the outer edge of the absorbent body and forming the outline of the absorbent article, the wing portion having a pair of side wing portions located on the outside of the transverse direction relative to a pair of imaginary straight lines extending in the longitudinal direction and passing through the outermost end of the transverse direction of the absorbent body, The absorbent body is located on the inner side of the side wing portion in the lateral direction. The outer edges of the pair of side wings have a pair of rear convex portions in the rear region, which are located forward of the longitudinal direction relative to the longitudinal rear ends of the wings and protrude outward in the lateral direction relative to the peripheral portions. A portion of the outer edge of the wing portion sandwiched between the longitudinal rear end of the wing portion and the rear convex portion has an inwardly convex curved portion having a center of curvature outside the outer edge, The inward convex curved portion is a single curved shape consisting of curved lines extending from the longitudinal rear end of the wing and the rear convex portion as starting points to a single convex top located between the two starting points, and the top is located at a position forward of the longitudinal direction relative to the longitudinal rear end of the absorbent body.

2. The absorbent article according to claim 1, wherein: The outer edge of the longitudinal rear end portion of the wing portion has an outwardly convexly curved portion having a center of curvature inside the outer edge, and the outwardly convexly curved portion has a smaller radius of curvature than the inwardly convexly curved portion.

3. The absorbent article according to claim 1 or 2, characterized in that: The outer edge of the absorbent body has a rearward curved portion connected to the longitudinal rear end of the absorbent body and extending along the inwardly convexly curved portion of the outer edge of the wing portion.

4. The absorbent article according to claim 1 or 2, characterized in that: The outer edge of the side wing portion has a rear narrowing portion that is located forward of the rear convex portion in the longitudinal direction and connected to the rear convex portion and that curves inward in the lateral direction.

5. The absorbent article according to claim 4, wherein: The outer edge of the side wing portion has a front narrowing portion that is bent inward in the lateral direction in the front region.

6. The absorbent article according to claim 5, characterized in that: In the region overlapping the absorbent body in a plan view, the compression recovery property of the region between the narrowed portions located between the rear narrowed portion and the front narrowed portion in the longitudinal direction is higher than the compression recovery property of the region adjacent to the region between the narrowed portions in the longitudinal direction.

7. The absorbent article according to claim 6, wherein: The ratio of the compression work WC of the region between the constricted portions to the compression work WC of the region in front of or behind the region in the longitudinal direction is 1.5 or more when expressed as the former / the latter.

8. The absorbent article according to any one of claims 5 to 7, characterized in that: The absorbent body has a fiber block layer, which contains absorbent fibers and fiber blocks containing non-absorbent fibers, the fiber blocks are intertwined with each other, or the fiber blocks are intertwined with the absorbent fibers, and the fiber block layer mainly contains the fiber blocks. The fiber block layer is present in the inter-narrowing region between the rear narrowing and the front narrowing in the longitudinal direction.

9. The absorbent article according to claim 1 or 2, characterized in that: A pair of the rear convex parts exist in the rearmost region when the absorbent article is divided into three equal parts in the longitudinal direction, and the transverse length of the rearmost region is the longest between the pair of rear convex parts.

10. The absorbent article according to claim 1 or 2, characterized in that: The angle formed by two imaginary straight lines connecting the longitudinal rear end of the wing portion and the tops of the pair of rear convex portions is greater than or equal to 40° and less than or equal to 100°.

11. The absorbent article according to claim 1 or 2, characterized in that: The ratio of the longitudinal length L1 between the rear convex portion and the longitudinal rear end of the wing portion to the lateral length L2 of the area between the rear convex portion and the longitudinal rear end of the wing portion is greater than 0.5 and less than 1.3 when expressed as L2 / L1.

12. The absorbent article according to claim 1 or 2, characterized in that: The wing portion at the same position as the longitudinal rear end of the absorbent body in the longitudinal direction has a length in the transverse direction of 45 mm to 90 mm.

13. The absorbent article according to claim 1 or 2, characterized in that: When assuming a triangle with an imaginary straight line connecting the longitudinal front end and the longitudinal rear end of the inwardly convex curved portion as the base, and two imaginary straight lines connecting the top of the inwardly convex curved portion and the longitudinal front end and the longitudinal rear end respectively as the two sides, the angle formed by the vertex of the longitudinal front end and the angle formed by the vertex of the longitudinal rear end in the triangle are respectively greater than 3° and less than 35°.

14. The absorbent article according to claim 1 or 2, characterized in that: The inwardly convexly curved portion includes a portion overlapping with the absorbent body in the longitudinal direction, and the proportion of the portion in the inwardly convexly curved portion is 50% or more.

15. The absorbent article according to claim 1 or 2, characterized in that: The absorbent body includes absorbent fibers and fiber masses including non-absorbent fibers, the fiber masses being entangled with each other or the fiber masses being entangled with the absorbent fibers.

16. The absorbent article according to claim 15, characterized in that: The absorbent body includes a fiber block layer mainly composed of the fiber block.

17. The absorbent article according to claim 16, wherein: In the excretion part-facing region, the skin-facing side of the absorbent body is formed by an absorbent core mainly composed of absorbent fibers and absorbent polymer particles, and the non-skin-facing side of the absorbent body is formed by the fiber block layer.

18. The absorbent article according to claim 16 or 17, wherein: The fiber block layer is a region where the fiber blocks exist over the entire length of the absorbent body in the transverse direction.

19. The absorbent article according to claim 16 or 17, wherein: The fiber block layer is composed only of the fiber blocks.

20. The absorbent article according to claim 1 or 2, characterized in that: The absorbent article is a sanitary napkin.

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