Absorbent articles

Abstract

This invention relates to an absorbent article that can achieve both improved resistance to twisting of the absorbent material in the intermediate range and good fit. [Solution] The absorbent article comprises a surface sheet, a back sheet, an absorbent body, and a slip-preventing portion. In a plan view of the absorbent article, the region where the absorbent body exists has a central region, an outer region, and a slip-preventing portion located between the central region and the outer region. The central region is located in the lateral center of the absorbent body, including the vertical center line. The outer region is located on both lateral sides of the absorbent body. The absorbent body comprises an absorbent core, a non-skin side core wrap sheet covering the non-skin side of the absorbent core, and a non-skin side core adhesive that adheres the absorbent core and the non-skin side core wrap sheet. The non-skin side core adhesive is present along the entire length of the longitudinal middle region of the absorbent article. In the region where the absorbent body exists in the intermediate region, the area ratio of the non-skin side core adhesive is higher in the region where the slip-preventing portion exists than in the central region and the outer region, in each of the left and right regions separated by the vertical center line.

Description

Technical Field

[0001] The present invention relates to absorbent articles such as sanitary napkins.

Background Art

[0002] Generally, a non-slip portion for fixing the sanitary napkin to underwear is provided on the back surface of the sanitary napkin.

[0003] In Patent Document 1, in order to suppress the sagging of the entire absorber, a plurality of linear absorber adhesives along the longitudinal direction are provided between the absorbent core and the core wrap sheet disposed on the non-skin side of the absorbent core to prevent the occurrence of gaps. An absorbent article is disclosed. In this absorbent article, in order to improve the fit to the excretion part, a bending guide part is provided between the non-slip adhesive layers at the center in the width direction. The bending guide part is formed as a linear compression part having a central depression recessed toward the skin side, and guides the absorbent article to bend toward the skin side.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the absorbent article described in Cited Document 1, a plurality of absorber adhesives linearly extending in the longitudinal direction (vertical direction) are evenly arranged in the width direction. Therefore, when an external force acting inward in the width direction (lateral direction) is applied to the absorbent article during wearing or the like, the force cannot be effectively transmitted to the bending guide portion located at the center in the lateral direction, and sufficient fit is difficult to obtain. Further, in the absorbent article described in Cited Document 1, since a plurality of linear absorber adhesives are provided over the entire width direction of the absorbent core, the rigidity of both lateral portions of the absorber in the lateral direction becomes high, and it is difficult to fit.

[0006] The object of the present invention is an absorbent article that can achieve both improved resistance to twisting of the absorbent material in the longitudinal intermediate region and good fit. [Means for solving the problem]

[0007] An absorbent article according to one embodiment of the present invention has a longitudinal direction corresponding to the wearer's front-to-back direction and a transverse direction corresponding to the wearer's left-to-right direction, both of which are orthogonal to each other. The absorbent material described above is divided into a front area, an intermediate area, and a rear area along the longitudinal direction. The absorbent article comprises a surface sheet, a back sheet, an absorbent material disposed between the surface sheet and the back sheet, and a plurality of vertically extending anti-slip portions arranged on the non-skin side of the back sheet. In a plan view of the absorbent article, the region where the absorbent material exists comprises a central region, an outer region, and the anti-slip portion. The aforementioned central region is located in the horizontal center, including the vertical center line that bisects the absorber horizontally. The anti-slip portion is not positioned along the entire length of the central region. The aforementioned outer region is located on both lateral sides, including the lateral side edges of the absorber described above. The anti-slip portion is not arranged along the entire length in the longitudinal direction in the aforementioned outer region. The anti-slip portion is positioned between the central region and the outer region. The absorbent material comprises a non-skin side core wrap sheet and a non-skin side core adhesive. The non-skin side core wrap sheet described above covers the non-skin side of the absorbent core described above. The above non-skin side core adhesive adheres the above absorbent core and the above non-skin side core wrap sheet. The above-mentioned non-skin core adhesive is present at least along the entire length in the longitudinal direction of the intermediate region. In the region of the intermediate area where the absorbent material exists in a plan view, the area ratio of the non-skin side core adhesive is higher in the region where the anti-slip portion exists than in the central region and the outer region, in each of the left and right regions separated by the vertical center line. [Effects of the Invention]

[0008] According to the absorbent article of the present invention, it is possible to achieve both resistance to twisting of the absorbent material in the longitudinal intermediate region and a good fit. [Brief explanation of the drawing]

[0009] [Figure 1] This is a plan view showing an absorbent article according to one embodiment of the present invention as seen from the skin side. [Figure 2] This is a plan view of the absorbent material shown above, viewed from a non-skin side. [Figure 3] This is a schematic cross-sectional view of the intermediate region of an absorbent material, cut along the line III-III in Figure 1. [Figure 4] This is a schematic cross-sectional view of the intermediate region of an absorbent material cut along the line VI-VI in Figure 1. [Figure 5] This is a partially enlarged view of Figure 3, a schematic cross-sectional view illustrating the positional relationship between the absorbent core, the non-skin side core wrap sheet, and the anti-slip portion. [Figure 6] This is a plan view of an absorbent core that constitutes a part of the above-mentioned absorbent article, and is a diagram for explaining the positional relationship between the components of the absorbent core, the non-skin side core adhesive, and the shear prevention portion. [Figure 7] This is a schematic, partially enlarged cross-sectional view of the intermediate region of an absorbent article as a modified example. [Figure 8] This is an explanatory diagram of a method for measuring compression load in the groin area. (a) is a schematic top view of the measuring instrument used in the measurement method (viewed from the skin side of the measurement sample indicated by reference numeral 100), and (b) is a schematic side view of the measuring instrument (viewed from one end in the longitudinal direction of the measurement sample indicated by reference numeral 100). [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described below with reference to the drawings. Each drawing shows, as appropriate, mutually orthogonal coordinate axes, namely the X, Y, and Z axes. In the following description, previously mentioned components will be denoted by the same reference numerals, and their descriptions may be omitted.

[0011] <Overall Structure of Absorbent Article> An absorbent article 1 according to an embodiment of the present invention is configured as a sanitary napkin and is hereinafter referred to as napkin 1. Napkin 1 has a longitudinal direction X corresponding to the front-back direction of the wearer and a lateral direction Y corresponding to the left-right direction of the wearer and orthogonal to the longitudinal direction X. Further, napkin 1 has a thickness direction Z orthogonal to both the longitudinal direction X and the lateral direction Y. The longitudinal direction X coincides with the longitudinal direction of napkin 1, and the lateral direction Y coincides with the width direction of napkin 1. In this specification, with respect to the thickness direction Z, the side closer to the wearer's skin may be expressed as up or the skin side, and the side closer to the underwear may be expressed as down or the non-skin side. In this specification, "plan view" means a plan view seen from the thickness direction Z. In this specification, unless otherwise specified, "inside the lateral direction Y" means approaching the lateral direction Y toward the longitudinal center line CL that bisects the lateral direction Y of napkin 1, and "outside the lateral direction Y" means moving away from the longitudinal center line CL in the lateral direction Y. The longitudinal center line CL coincides with the longitudinal center line that bisects the lateral direction Y of the absorber described later. In this specification, "width" and "lateral width" mean the length of the lateral direction Y.

[0012] As shown in FIG. 1, the absorbent article 1 includes a main body M, a pair of wings W, and a pair of hip guards H.

[0013] The main body M extends in a strip shape along the longitudinal direction X and is fixed to the inner surface of the wearer's underwear during wearing. The main body M is divided into a front region M1, an intermediate region M2, and a rear region M3 along the longitudinal direction X. The intermediate region M2 includes an excretion part facing region that faces the excretion part of the wearer during wearing. The excretion part facing region is located at the center in the lateral direction Y of the intermediate region M2. The excretion part is the vaginal opening when the absorbent article is napkin 1. In napkin 1, the intermediate region M2 is a region that overlaps with the region where the wing W is provided in the longitudinal direction X. The intermediate region M2 is a region where an external force acting from both legs of the wearer toward the inside of the lateral direction Y is applied during wearing. The front region M1 is an area disposed in front of the middle region M2 (on the ventral side of the wearer), and faces the front of the wearer's excretion part when worn. The rear region M3 is an area disposed behind the middle region M2 (on the dorsal side of the wearer), and faces the rear of the wearer's excretion part when worn. In the diaper 1, the rear region M3 is an area that overlaps with the area where the hip guard H is provided in the longitudinal direction X. The "when worn" mentioned here means a state in which the normal proper wearing position (the assumed wearing position of the diaper 1) is maintained, and does not include the case where the diaper 1 is displaced from the wearing position.

[0014] The main body M extends along the longitudinal direction X and is disposed on the inner surface of the wearer's underwear. The main body M has a function of absorbing liquid substances such as the wearer's menstrual blood (hereinafter also referred to as "liquid").

[0015] A pair of wings W extend outward in the lateral direction Y from the middle region M2 of the main body M. The wings W extend outward in the lateral direction from the underwear under the wearer's crotch, are folded inward, and are fixed to the outer surface of the underwear. Thereby, the middle region M2 of the main body M can be prevented from being displaced from under the wearer's crotch.

[0016] A pair of hip guards H extend outward in the lateral direction Y from the rear region M3 of the main body M and partially wrap the buttocks on the inner side of the wearer's underwear. The hip guard H is located behind the wing W.

[0017] As shown in FIG. 1, the diaper 1 has a constricted portion between the wing W and the hip guard H, where the left and right side edges along the longitudinal direction X are constricted inward in the lateral direction Y. In the diaper 1 according to the present embodiment, the front end portion of the hip guard H coincides with the rear end portion of the wing W.

[0018] As shown in Figures 1-4, the napkin 1 comprises a surface sheet 2, an absorbent core 4, a back sheet 3, and a pair of side sheets 5. In the main body M, the napkin 1 has a structure in which the back sheet 3, absorbent core 4, and surface sheet 2 are laminated in the thickness direction Z. These components are joined and integrated as appropriate by means of bonding, such as adhesive or heat sealing, or by compression processing by the round compression section 6 and the first lateral compression section 12.

[0019] The surface sheet 2 is positioned above the absorbent body 4 in the thickness direction Z. A fourth adhesive 54 is placed between the surface sheet 2 and the absorbent body 4, and the two are bonded together by the fourth adhesive 54. A pair of side sheets 5 extend in the vertical direction X and are positioned on both the left and right sides of the surface sheet 2. The side sheets 5 are provided across both the left and right sides of the main body M, the wings W, and the hip guard H. The side sheets 5 are bonded to the surface sheet 2 by adhesive E, for example. The back sheet 3 is positioned below the absorbent body 4 in the thickness direction Z. The back sheet 3 is provided across the entire main body M, the wings W, and the hip guard H. Both the surface sheet 2 and the side sheets 5 are located on the back sheet 3. The back sheet 3 is bonded to the surface sheet 2 and the side sheets 5 by a third adhesive 53, heat sealing, etc., for example, at its periphery. The third adhesive 53 is also applied to almost the entire non-skin side of the absorbent body 4, bonding the absorbent body 4 to the back sheet 3.

[0020] The surface sheet 2 is made of a highly permeable sheet material so that it can effectively take in liquids such as menstrual blood from the top into the interior. On the other hand, the back sheet 3 and side sheet 5 are made of a low-permeability sheet material (i.e., a leak-proof sheet material) to prevent liquids taken in from the surface sheet 2 from leaking to the outside. The surface sheet 2, back sheet 3, and side sheet 5 can be the same as those conventionally used in the art, without any particular limitations. For example, the surface sheet 2 can be made of a nonwoven fabric or a perforated film that is permeable to liquids. The back sheet 3 can be made of a liquid-impermeable film made of synthetic resin or a water-repellent nonwoven fabric with high water pressure resistance, such as a spunbond-meltblown-spunpound laminated nonwoven fabric. The side sheet 5 can be made of a water-repellent nonwoven fabric with high water pressure resistance, such as a spunbond-meltblown-spunpound laminated nonwoven fabric.

[0021] On the non-skin side of the back sheet 3, anti-slip portions 31-34 are provided to secure the main body M, wing W, and hip guard H to the underwear. Hereinafter, the surface on which the anti-slip portions 31-34 are provided on the napkin 1 will also be referred to as the underwear contact surface 3a. As shown in Figures 3 and 4, the wing W is constructed by laminating the side sheet 5 and the back sheet 3 in the thickness direction Z. The underwear contact surface 3a of the wing W is provided with a wing anti-slip portion 33. The hip guard H is constructed by laminating the side sheet 5 and the back sheet 3 in the thickness direction Z. The underwear contact surface 3a of the hip guard H is provided with a hip guard anti-slip portion 34. The underwear contact surface 3a of the main body M is provided with a front anti-slip portion 31 and a rear anti-slip portion 32. Details of the anti-slip portions 31-34 will be described later.

[0022] The absorbent material 4 extends along the longitudinal direction X and is positioned between the surface sheet 2 and the back sheet 3. The absorbent material 4 absorbs liquid from the surface side of the surface sheet 2 and diffuses it internally to retain the liquid. As the absorbent material 4, any material similar to those conventionally used in the art can be used without particular limitations. In the napkin 1, the absorbent material 4 extends from the front region M1 through the middle region M2 to the rear region M3.

[0023] As shown in Figures 2 to 4, when the absorbent 4 is divided into three equal parts in the lateral direction Y, it has a central absorbent portion 45 located in the center of the lateral direction Y, and a pair of lateral absorbent portions 46 located on each side of the lateral direction Y. The lateral absorbent portions 46 include the lateral edge 4s of the absorbent 4 and are regions located inward from the lateral edge 4s in the lateral direction Y.

[0024] As shown in Figure 5, in a plan view of the intermediate region M2, in the region where the absorber 4 exists, when the region is divided in half horizontally along the vertical center line CL, the left side is called the first intermediate region absorber region 41, and the right side is called the second intermediate region absorber region 42.

[0025] The absorbent body 4 comprises an absorbent core 7 and a core wrap sheet 8.

[0026] The absorbent core 7 may be formed from a fiber aggregate composed of hydrophilic fibers such as pulp fibers, or it may have a structure in which an absorbent polymer is held within the fiber aggregate. The absorbent core 7 has a non-skin side 7a and a skin side 7b. Details of the absorbent core 7 will be described later.

[0027] The core wrap sheet 8 covers the absorbent core 7 and has functions such as maintaining the shape of the absorbent core 7. The core wrap sheet 8 is made of, for example, a thin, soft paper like tissue paper or a liquid-permeable nonwoven fabric. The core wrap sheet 8 includes a non-skin side core wrap sheet 81 that covers the non-skin side 7a of the absorbent core 7 and a skin side core wrap sheet 82 that covers the skin side 7b of the absorbent core 7.

[0028] In this embodiment, the core wrap sheet 8 covers the non-skin side 7a and skin side 7b of the absorbent core 7 with a single continuous core wrap sheet, but it may be composed of multiple core wrap sheets. For example, it may include one non-skin side core wrap sheet covering the non-skin side 7a of the absorbent core 7 and one skin side core wrap sheet covering the skin side 7b. The absorbent core 7 and the non-skin side core wrap sheet 81 are bonded together by a non-skin side core adhesive S1. The absorbent core 7 and the skin side core wrap sheet 82 may also be bonded together by a skin side core adhesive S2. Figures 3 and 4 are schematic cross-sectional views. In Figures 3 and 4, the skin side core adhesive S2 is shown with a thickness for convenience, so there is a gap between the skin side core wrap sheet 82 and the absorbent core 7, but in reality, the skin side core wrap sheet 82 and the absorbent core 7 are in contact without any gaps. Details of the core wrap sheet 8 will be described later.

[0029] <Detailed composition of absorbent material> [Non-skin side core wrap sheet] As shown in Figure 5, the non-skin side core wrap sheet 81 has a left side portion 81sL, which is one side in the transverse direction Y, specifically the left side, and a right side portion 81sR, which is the other side in the transverse direction Y, specifically the right side. The left side portion 81sL and the right side portion 81sR face each other in the transverse direction Y. The non-skin side core wrap sheet 81 includes a first core wrap sheet 811 and a second core wrap sheet 812. As shown in Figures 3 to 5, the first core wrap sheet 811 extends from the left side 81sL toward the right side 81sR to near the center of the central part 45 of the absorbent in the lateral direction Y. The second core wrap sheet 812 extends from the right side 81sR toward the left side 81sL to the central part 45 of the absorbent.

[0030] As shown in Figure 5, the non-skin side core wrap sheet 81 has a sheet overlapping region B in which the first core wrap sheet 811 and the second core wrap sheet 812 overlap in the thickness direction Z. In the napkin 1 of this embodiment, in the sheet overlapping region B, the second core wrap sheet 812 located on the right side in the figure is located above the first core wrap sheet 811 located on the left side (skin side, absorbent core 7 side), but the second core wrap sheet 812 may be located above the first core wrap sheet 811.

[0031] The sheet overlapping region B exists over at least the entire length of the longitudinal X direction of the intermediate region M2 (the entire length of the longitudinal X direction), and in napkin 1, it exists over the entire length of the longitudinal X direction of the absorbent core 7. In napkin 1, in a plan view, the sheet overlapping region B is located near the center of the transverse Y direction of napkin 1, including the vertical center line CL, and is located in the central part 45 of the absorbent material.

[0032] [Anti-slip section] As shown in Figure 2, the napkin 1 includes a pair of forward anti-slip portions 31 spaced apart in the lateral direction Y, a pair of rear anti-slip portions 32 spaced apart in the lateral direction Y, a pair of wing anti-slip portions 33, and a pair of hip guard anti-slip portions 34, all positioned on the underwear contact surface 3a. These anti-slip portions are formed by applying an adhesive such as a hot-melt adhesive to the underwear contact surface 3a of the back sheet 3.

[0033] (Wing slip prevention section) As shown in Figure 2, a pair of wing anti-slip sections 33 are arranged on each of the pair of wings W. The wing anti-slip sections 33 have the function of fixing the folded wing W to the outer surface of the wearer's underwear. The wing anti-slip section 33 is divided into three sections in the horizontal direction Y, and three rectangular vertical anti-slip sections 330 extending in the vertical direction X are intermittently provided in the horizontal direction Y. Note that the wing anti-slip section 33 does not have to be divided, and may be divided into two or four or more sections. The same applies to the hip guard anti-slip section 34 described later.

[0034] (Hip guard anti-slip section) As shown in Figure 2, a pair of hip guard anti-slip sections 34 are arranged on each of the pair of hip guards H. The hip guard anti-slip sections 34 have the function of fixing the hip guards H to the inner surface of the wearer's underwear. The hip guard anti-slip section 34 is divided into three sections in the horizontal direction, and is composed of three rectangular vertical anti-slip sections 340 extending in the vertical direction X and intermittently provided in the horizontal direction Y.

[0035] (Front anti-slip section and rear anti-slip section) The pair of front anti-slip portions 31 and the pair of rear anti-slip portions 32 have the function of fixing the main body M to the inner surface of the wearer's underwear. As shown in Figure 2, in a plan view, the front anti-slip portions 31 and rear anti-slip portions 32 are located in the area where the absorbent material 4 is present on the main body M of the napkin 1, and no anti-slip portions are present in the area where the absorbent material 4 is not present. The forward anti-slip portion 31 extends continuously in the vertical direction X across a portion of the forward area M1, the intermediate area M2, and a portion of the rear area M3. One forward anti-slip portion 31 is positioned on each side of the vertical center line CL, with one in between, and is provided as a pair on the left and right. The rearward anti-slip portion 32 extends continuously in the vertical direction X towards the rear of the rear area M3. One rearward anti-slip portion 32 is positioned on each side of the vertical center line CL, with the vertical center line CL in between, and is provided in pairs.

[0036] As shown in Figure 2, on the underwear contact surface 3a, the pair of rearward anti-slip portions 32 are positioned behind the pair of front anti-slip portions 31 in the vertical direction X, with an intermittent region 35 in between. The intermittent region 35 is the area between the pair of front anti-slip portions 31 and the pair of rearward anti-slip portions 32, over the entire lateral direction Y of the main body M, where no anti-slip portions exist. In other words, the front anti-slip portions 31 and the rearward anti-slip portions 32 are separated in the vertical direction X. Both the front anti-slip portions 31 and the rearward anti-slip portions 32 have a rectangular shape that is elongated in the vertical direction X. When worn, the intermittent region 35 includes a portion located in the longitudinal direction X that corresponds to the vicinity of the wearer's anus.

[0037] A relatively long napkin (290 mm or more in length), like the napkin 1 of this embodiment, is generally suitable for use during sleep or when lying on one's back. When the wearer lies on their back while wearing the napkin 1, the area around the intermittent region 35 is a position where the wearer's body pressure is easily applied. By not having an anti-slip portion in this pressure-sensitive area, the anti-slip portion is less likely to remain on the underwear when the napkin is removed, resulting in an easy-to-handle napkin.

[0038] As shown in Figures 2 to 4, in the area where the absorbent material 4 of the intermediate region M2 of the napkin 1 is located in a plan view, a central region 36 is located between the pair of forward anti-slip portions 31, where no anti-slip portions are placed along the entire length of the intermediate region M2 in the vertical direction X. Furthermore, on both the left and right sides of the pair of forward anti-slip portions 31, there are outer regions 37 where no anti-slip portions are placed along the entire length of the intermediate region M2 in the vertical direction X. In other words, the area where the absorbent material 4 of the intermediate region M2 of the napkin 1 is located in a plan view has a central region 36, an outer region 37, and forward anti-slip portions 31, with the forward anti-slip portions 31 being located between the central region 36 and the outer region 37. Furthermore, in the napkin 1 of this embodiment, the central region 36 and the outer region 37, where the anti-slip portion is not continuously arranged in the vertical direction X, extend not only to the intermediate region M2 but also to the entire length of the vertical direction X of the region where the absorbent material 4 is present in a plan view.

[0039] As shown in Figures 2 to 4, the central region 36 is located in the center of the transverse direction Y, which includes the vertical center line CL of the napkin 1. The central region 36 is located in the central part 45 of the absorbent material. The outer region 37 is located on the lateral portion 46 of the absorber. Of the pair of outer regions 37, the one on the left is called the first outer region 371, and the one on the right is called the second outer region 372, but unless there is a need to distinguish between them, they are referred to as outer region 37.

[0040] As shown in Figure 5, the central region 36 is divided by the vertical center line CL, and has a first central region 361 located to the left of the vertical center line CL, and a second central region 362 located to the right of the vertical center line CL.

[0041] [Non-skin core adhesive] As shown in Figures 3 to 5, the non-skin side core adhesive S1 is placed between the absorbent core 7 and the non-skin side core wrap sheet 81, and adheres the non-skin side 7a of the absorbent core 7 to the non-skin side core wrap sheet 81. The non-skin side core adhesive S1, the skin side core adhesive S2, the third adhesive 53, and the fourth adhesive 54 are not particularly limited as long as they are adhesives that can be used in absorbent articles, but are preferably adhesives mainly composed of synthetic resin, and are typically hot-melt type adhesives.

[0042] As shown in Figures 1 and 2, the non-skin side core adhesive S1 extends in the longitudinal direction X. The non-skin side core adhesive S1 is provided continuously in the longitudinal direction X over almost the entire length of the absorbent core 7 in the longitudinal direction X. "The non-skin side core adhesive S1 extends in the vertical direction X" means that the non-skin side core adhesive S1 as a whole extends from front to back. More specifically, "the non-skin side core adhesive S1 extends in the vertical direction X" is not limited to the non-skin side core adhesive S1 extending in a linear manner parallel to the vertical direction X, but also includes manners in which it extends diagonally with respect to the vertical direction X, or locally curved or meandering. Furthermore, the non-skin side core adhesive S1 is not limited to being applied continuously in the vertical direction X, but may also be applied intermittently in a manner that is continuous, such as a spiral, where within the application area A10 of one non-skin side core adhesive S1 there are breaks on an imaginary line extending in the vertical direction X, but the adhesive is applied intermittently. Specific application patterns for the non-skin side core adhesive S1 include, as an example of continuous application, a linear shape, a spiral shape in which the adhesive is intermittently arranged on an imaginary line extending in the vertical direction X, a dot shape, a dashed line shape, etc. In the example shown in Figure 2, the non-skin-side core adhesive S1 is applied in a spiral pattern extending in the vertical direction X. The same applies to the skin-side core adhesive S2, which will be described later. In addition, in Figure 5 and Figure 7, which shows a modified example described later, each adhesive, including the non-skin side core adhesive S1, is schematically represented by multiple circles that depict a spiral shape. In Figures 3 and 4, each adhesive, including the non-skin side core adhesive S1, is schematically shown in layers to make the coating area easier to understand.

[0043] As shown in Figures 2 to 5, the area obtained by surrounding the outer edge of the coating area of ​​the non-skin side core adhesive S1 in a roughly rectangular shape is called the non-skin side core adhesive coating area A10. In napkin 1, the non-skin side core adhesive S1 is applied so that there is one non-skin side core adhesive coating area A10 on each side of the vertical center line CL, forming a pair. Similarly, the region obtained by surrounding the outer edge of the coating area of ​​the skin-side core adhesive S2 in a roughly rectangular shape is referred to as the skin-side core adhesive coating area A2.

[0044] As shown in Figures 3 and 4, in the middle region M2 of napkin 1, each pair of non-skin-side core adhesive coated areas A10 has a band shape extending in the vertical direction X. The pair of non-skin-side core adhesive coated areas A10 are spaced apart in the horizontal direction Y. The region surrounding the two non-skin-side core adhesive coated areas A10 is referred to as the overall non-skin-side core adhesive coated area A1.

[0045] As shown in Figures 3 and 4, the entire non-skin side core adhesive coating area A1 has a pair of side edges S1s facing each other in the lateral direction Y. The skin side core adhesive coating area A2 has a pair of side edges S2s facing each other in the lateral direction Y.

[0046] As shown in Figure 5, the first core wrap sheet 811 is located below the second core wrap sheet 812 in the sheet overlapping region B. The first core wrap sheet 811 has a core wrap non-adhesion region 401 on its skin side where no adhesive is applied. The non-adherent core-wrap region 401 is an adhesive-free region where no adhesive is present. In a plan view, the non-adherent core-wrap region 401 is located in the sheet overlap region B, and at least a portion of it is located in the central region 36. The non-adherent core-wrap region 401 is a region where the first core-wrap sheet 811 and the second core-wrap sheet 812 are not bonded to each other by adhesive because there is no adhesive placed between them. In a plan view, the non-adherent core-wrap region 401 is located so as to include the vertical center line CL.

[0047] Furthermore, as shown in Figure 5, the napkin 1 of this embodiment may have a first lateral non-skin side core adhesive-free region (non-skin side core adhesive-free region) 402 on its skin side where the non-skin side core adhesive S1 is not present. In a plan view, the first lateral non-skin side core adhesive-free region 402 is located in a region that does not overlap with the second core wrap sheet 812 and is located in the first outer region 371.

[0048] In Figure 5, the non-adhesive region 401 between core wraps is represented by a dashed rectangle, and the first lateral non-skin side core adhesive-free region 402 is represented by a dashed rectangle.

[0049] Furthermore, in napkin 1, as shown in Figure 5, the non-skin side core wrap sheet 81 has a core wrap non-adhesion region 401 in the sheet overlap region B where the first core wrap sheet 811 and the second core wrap sheet 812 are not adhered to each other, as well as a core wrap adhesion region D where the first core wrap sheet 811 and the second core wrap sheet 812 are adhered to each other by the non-skin side core wrap sheet adhesive Sd.

[0050] As shown in Figure 5, the second core wrap sheet 812 is located above the first core wrap sheet 811 in the sheet overlapping region B. The second core wrap sheet 812 has a central non-skin side core adhesive-free region (non-skin side core adhesive-free region) 403 on its skin side where the non-skin side core adhesive S1 is not present. In a plan view, the central non-skin side core adhesive-free region 403 is located in the sheet overlap region B, and at least a portion of it is located in the central region 36. In a plan view, the central non-skin side core adhesive-free region 403 is located so as to include the vertical center line CL.

[0051] Furthermore, as shown in Figure 5, the napkin 1 of this embodiment may have a second lateral non-skin side core adhesive-free region 404 on its skin side where the non-skin side core adhesive S1 is not present. In a plan view, the second lateral non-skin side core adhesive-free region 404 is located in a region that does not overlap with the first core wrap sheet 811 and is located in the second outer region 372.

[0052] In Figure 5, the central non-skin side core adhesive-free region 403 and the second lateral non-skin side core adhesive-free region 404 are represented by dashed rectangles.

[0053] The sheet overlapping region B, the first lateral non-skin side core adhesive-free region 402, the core wrap non-adhesion region 401, the core wrap adhesion region D, the central non-skin side core adhesive-free region 403, and the second lateral non-skin side core adhesive-free region 404 all exist along the entire length in the longitudinal direction X of the absorbent 4 located in the intermediate region M2, and in the napkin 1, they exist along the entire length in the longitudinal direction X of the absorbent 4 located across the anterior region M1, the intermediate region M2, and the posterior region M3.

[0054] As shown in Figure 5, in the absorbent 4, the non-skin side core wrap sheet 81 has a double-sided non-adhesive region C, which is the region where the non-adhesive region 401 between the core wraps and the central non-skin side core adhesive-free region 403 overlap in a plan view. In the napkin 1 of this embodiment, the non-adherent core-wrap region 401 and the adherent core-wrap region D are located in the sheet overlap region B. The second core wrap sheet 812 located in the double-sided non-adhesive region C does not have the non-skin side core adhesive S1 on its skin side, nor the non-skin side core wrap sheet adhesive Sd on its non-skin side, and the second core wrap sheet 812 located in the double-sided non-adhesive region C is not fixed to any other components. In napkin 1, in the sheet overlapping region B, the region where the second core wrap sheet 812 faces the non-adhesive region 401 between the core wraps of the first core wrap sheet 811 in the thickness direction Z includes a region where the non-skin side core adhesive S1 and the non-skin side core wrap sheet adhesive Sd are not provided (double-sided non-adhesive region C), and a region where the non-skin side core adhesive S1 is provided only on the skin side of the second core wrap sheet 812.

[0055] As shown in Figure 5, the double-sided non-adhesive region C is divided by the vertical center line CL, and includes a first double-sided non-adhesive region C1 located to the left of the vertical center line CL, and a second double-sided non-adhesive region C2 located to the right of the vertical center line CL.

[0056] As shown in Figures 2 and 5, in the napkin 1 of this embodiment, in the intermediate region M2, in a plan view, the width of the non-skin side core adhesive coated area A10 is wider than the width of the forward slip-preventing portion 31, and in the second intermediate region absorbent area 42, the non-skin side core adhesive S1 is arranged such that in a plan view, the non-skin side core adhesive coated area A10 extends outward from each of the two side edges in the lateral direction Y of the forward slip-preventing portion 31. Furthermore, in the first intermediate region absorbent area 41, with respect to both side edges in the lateral direction Y of the forward slip-preventing portion 31, the non-skin side core adhesive coated area A10 extends outward in the lateral direction Y at the lateral outer side edge (outer edge), and the non-skin side core wrap sheet adhesive Sd extends inward in the lateral direction Y at the lateral inner side edge (inner edge).

[0057] Furthermore, the non-skin side core adhesive coating area A10 may be equal in width to the front anti-slip portion 31, and the non-skin side core adhesive S1 may be arranged such that, in a plan view, both side edges of the front anti-slip portion 31 in the lateral direction Y coincide with both side edges of the non-skin side core adhesive coating area A10. Alternatively, the width of the non-skin side core adhesive coating area A10 may be narrower than the width of the forward slip prevention portion 31, and the non-skin side core adhesive S1 may be arranged such that, in a plan view, both side edges of the forward slip prevention portion 31 in the lateral direction Y are located within the non-skin side core adhesive coating area A10.

[0058] When an external force is applied toward the center of the width during wear, from the viewpoint of suppressing twisting of the absorbent material in the intermediate region M2, it is preferable that, as in the napkin 1 of this embodiment, in the intermediate region M2, the width of the non-skin side core adhesive coated area A10 is wider than the width of the forward slip-prevention portion 31, and in at least one of the first and second intermediate region absorbent material areas 41, 42, the non-skin side core adhesive S1 is arranged so as to extend from both side edges in the lateral direction Y of the forward slip-prevention portion 31 in a plan view. In this way, the region of the absorbent material that overlaps with the forward slip-prevention portion 31 in a plan view has high rigidity and can suppress deformation. On the other hand, the region of the absorbent material that does not overlap with the forward slip-prevention portion 31 in a plan view has lower rigidity compared to the former and is therefore more likely to deform, making it easier to fit to the groin area in the outer region.

[0059] In the example shown in Figure 5, the width of the sheet overlapping region B and the width of the central region 36 between the pair of forward-preventing portions are approximately equal, and they overlap in a plan view. However, the example is not limited to this. Due to manufacturing positional misalignments that may occur during napkin production, the sheet overlapping region B and the central region 36 may not completely overlap in a plan view but may partially overlap. Also, the central region 36 may be wider or narrower than the sheet overlapping region B.

[0060] [Relative relationship of area ratio of non-skin core adhesive S1 in intermediate region M2] In napkin 1, in the first intermediate absorbent region 41, the area ratio of the non-skin side core adhesive S1 is higher in the region where the anterior anti-slip portion 31 is present than in the first central region 361 and the first outer region 371 where the anti-slip portion is absent. Furthermore, in the second intermediate absorbent region 42, the area ratio of the non-skin side core adhesive S1 is higher in the region where the anterior anti-slip portion 31 is present than in the second central region 362 and the second outer region 372 where the anti-slip portion is absent, resulting in a "relationship of the area ratio of the non-skin side core adhesive S1" (hereinafter referred to as configuration A). This achieves both resistance to twisting and a good fit for the absorbent 4 in the intermediate region M2 in the vertical direction X.

[0061] Here, when a sanitary napkin is worn, the napkin 1 is secured to the wearer's underwear by the anti-slip portion, including the anti-slip portion 31. In the middle region M2 of the napkin 1, the non-skin side core wrap sheet 81 is closer to the anti-slip portion 31 than the skin side core wrap sheet 82, and when a sanitary napkin is worn, the non-skin side core wrap sheet 81 is more easily pulled by the movement of the underwear to which the napkin 1 is secured via the anti-slip portion 31 than the skin side core wrap sheet 82. For this reason, gaps between the absorbent core 7 and the core wrap sheet 8 are more likely to occur between the absorbent core 7 and the non-skin side core wrap sheet 81, which is located closer to the anti-slip portion, than between the absorbent core 7 and the skin side core wrap sheet 82. In the napkin 1 of this embodiment, a non-skin side core adhesive S1 is provided between the absorbent core 7 and the non-skin side core wrap sheet 81, thereby suppressing the occurrence of gaps between the absorbent core 7 and the non-skin side core wrap sheet 81. In the intermediate region M2, even when external force is applied by the wearer during wear, the non-skin side core wrap sheet 81 is adhered to the absorbent core 7 by the non-skin side core adhesive S1, making it easier to maintain the shape of the absorbent core 7.

[0062] In the napkin 1 of this embodiment, a non-skin side core adhesive S1 is provided with respect to the forward slip-prevention portion 31 to suppress the occurrence of a gap between the absorbent core 7 and the non-skin side core wrap sheet 81, in the configuration A described above. In napkin 1, due to configuration A, in the intermediate region M2, the area of ​​the absorbent 4 that overlaps with the forward slip prevention portion 31 in a plan view has a relatively large area ratio of the non-skin side core adhesive S1, resulting in relatively higher rigidity. Therefore, when worn, when an external force is applied to the absorbent 4 in the intermediate region M2 toward the inside in the lateral direction Y, the absorbent 4 is less likely to follow the deformation of the underwear, and twisting in the lateral direction Y is easily suppressed. Combined with the suppression of gap formation between the absorbent core 7 and the non-skin side core wrap sheet 81 by the non-skin side core adhesive S1, the shape retention effect of the absorbent core 7 is improved, the resistance of the absorbent 4 to twisting is improved, and good liquid absorption can be maintained. On the other hand, in the intermediate region M2, the region overlapping with the central region 36 and the outer region 37 in a plan view of the absorbent 4 is configured as described above. Because the area ratio of the non-skin side core adhesive S1 is relatively small, the rigidity is relatively low and it is easily deformed. As a result, in the central region 36, the absorbent 4 is more likely to deform convexly toward the excretion area, making it easier to fit to the excretion area, and in the outer region 37, it is easier to fit to the groin area, improving wearing comfort and suppressing leakage. Thus, in napkin 1, by using composition A, both resistance to shifting and a good fit of the absorbent material 4 in the intermediate zone M2 are achieved.

[0063] [Specific examples for realizing Configuration A] To realize configuration A, for example, as shown in Figure 5, the napkin 1 of this embodiment may have a non-skin-side core adhesive-free region in the area overlapping with the central region 36 and the outer region 37 in a plan view of the absorbent material 4, where the non-skin-side core adhesive that bonds the non-skin-side core wrap sheet 81 and the absorbent core 7 does not exist, and this region may extend at least along the entire length of the intermediate region M2 in the vertical direction X. Details will be described later.

[0064] As another example, in order to realize configuration A, in the region where the absorber 4 of the intermediate region M2 exists, in a plan view, the non-skin side core adhesive may be applied only to a part of the region in the vertical direction X, leaving the majority uncoated. Alternatively, in order to realize configuration A, in the region where the absorber 4 of the intermediate region M2 exists, in a plan view, the region overlapping with the central region 36 and the outer region 37 may be configured such that in one region (central region 36 or outer region 37), the non-skin side core adhesive is applied only to a part of the vertical direction X, leaving the majority uncoated, while in the other region, a non-skin side core adhesive-free region is provided along the entire length of the vertical direction X.

[0065] As another example, in order to realize configuration A, a low-basis-weight non-skin adhesive coating area may be provided by coating the area where the absorber 4 in the intermediate area M2 exists, in a plan view, with a non-skin adhesive coating area such that the basis weight is lower than that of the non-skin adhesive coated in the non-skin core adhesive coating area A10 in Figure 5 (in other words, the non-skin adhesive coated in the area that roughly overlaps with the forward slip prevention portion 31 in a plan view). Alternatively, in order to realize configuration A, in the region where the absorber 4 in the intermediate region M2 exists, in a plan view, in the region that overlaps with the central region 36 and the outer region 37, one region (central region 36 or outer region 37) may be provided with a low basis weight non-skin side core adhesive coating area, and the other region may be provided with a non-skin side core adhesive-free area where the non-skin side core adhesive does not exist over the entire length in the vertical direction X. Furthermore, the area ratio of the non-skin core adhesive in the "low basis weight non-skin core adhesive coating area" is smaller than the area ratio of the non-skin core adhesive in the non-skin core adhesive coating area A10.

[0066] Furthermore, the methods for realizing Configuration A are not limited to those described herein.

[0067] (Detailed description of the configuration A, which is achieved by providing non-skin-side core adhesive-free areas in the central and outer regions) In a preferred embodiment of configuration A, as shown in Figure 5, in a plan view of the absorbent body 4, there are regions where the non-skin side core adhesive that bonds the non-skin side core wrap sheet 81 to the absorbent core 7 is absent, such as the napkin 1 shown in Figure 5. These regions (central non-skin side core adhesive-free region 403, first lateral non-skin side core adhesive-free region) extend over the entire length of the intermediate region M2, overlapping with the central region 36 and the outer region 37.

[0068] The following explanation concerns the region 41 where the first intermediate absorber exists, but the same explanation applies to the region 42 where the second intermediate absorber exists.

[0069] As shown in Figures 5 and 6, in napkin 1, the non-skin side core adhesive S1 located in the first intermediate absorbent region 41 is positioned such that it overlaps with the forward slip-prevention portion 31 in a plan view, has a portion that does not overlap with the first central region 361 in a plan view, and has a portion that does not overlap with the first outer region 371 in a plan view. In detail, the first intermediate absorbent region 41 has a first double-sided non-adhesive region C1 and a core-wrap adhesive region D, which overlap with the first central region 361 in a plan view and where the non-skin side core adhesive is absent along the entire length in the longitudinal direction X. The first intermediate absorbent region 41 has a first lateral non-skin side core adhesive-free region 402, which overlaps with the first outer region 371 in a plan view and where the non-skin side core adhesive is absent along the entire length in the longitudinal direction X. In a plan view, the non-skin side core adhesive S1 and the non-skin side core wrap sheet adhesive Sd are arranged between the first double-sided non-adhesive region C1 and the first lateral non-skin side core adhesive-free region 402 in the first intermediate absorbent region 41. In napkin 1, the first lateral non-skin side core adhesive-free region 402 is narrower than the first outer region 371. The same applies to the second intermediate absorber presence region 42, thereby realizing configuration A.

[0070] As shown in Figure 2, in the middle region M2 of napkin 1, the width of the non-skin side core adhesive coating area A10 located on the left side is wider than the width of the forward slip prevention portion 31 located on the left side, and the outer edge of the strip-shaped non-skin side core adhesive coating area A10 in the lateral direction Y extends slightly outward from the outer edge of the forward slip prevention portion 31 in the lateral direction Y. The non-skin side core adhesive S1 extending toward the first outer region 371 is located in a part of the first outer region 371 in a plan view, but the non-skin side core adhesive S1 is not present in other parts of the first outer region 371. On the other hand, the forward slip prevention portion 31 located on the left side overlaps with the non-skin side core adhesive S1 in a plan view.

[0071] Thus, in the napkin 1 of this embodiment, the intermediate region M2 includes areas in the central region 36 and the outer region 37 where the non-skin-side core adhesive is absent, making it easier to more reliably adjust the rigidity of the central region 36 and the outer region 37 to a lower level. As a result, in the central region 36, when the central region 36 deforms convexly toward the excretion area due to the external force applied by the wearer in the groin area in the lateral direction Y, the internal force is mitigated, further suppressing the twisting of the absorbent material 4, and consequently making it easier to maintain the deformed convex shape well. On the other hand, in the outer region 37, the rigidity of the absorbent material 4 facing the groin area is reduced, making the absorbent material 4 more easily deformable, and further improving the fit to the groin area.

[0072] In the intermediate region M2, the central non-skin side core adhesive-free region 403, the first lateral non-skin side core adhesive-free region 402, and the second lateral non-skin side core adhesive-free region 404 may have areas that overlap with the forward slip-preventing portion 31 in a plan view, but from the viewpoint of suppressing twisting of the absorber 4 due to the relaxation of internal forces, it is preferable that they do not overlap as much as possible. From the viewpoint of effectively suppressing twisting of the absorber 4 by easing the internal force as described above, the ratio of the length in the lateral direction Y of the portion where the central non-skin side core adhesive-free region 403 overlaps with the central region 36 in a plan view to the length in the lateral direction Y of the portion where the central non-skin side core adhesive-free region 403 overlaps with the forward slip-preventing portion 31 in a plan view is preferably 0.5 or less, more preferably 0.3 or less, with a lower limit of preferably 0.1, more preferably 0. As specific numerical examples, the lateral Y length of the portion where the central non-skin side core adhesive-free region 403 overlaps with the central region 36 in a plan view is approximately 5 mm to 10 mm, and the lateral Y length of the portion where the central non-skin side core adhesive-free region 403 overlaps with the forward slip-prevention portion 31 in a plan view is approximately 0 mm to 5 mm (0 mm in the example shown in Figure 5). Note that the values ​​are not limited to those listed here.

[0073] Furthermore, as shown in Figure 5, the napkin 1 of this embodiment, it is preferable that the non-skin side core wrap sheet 81 has a sheet overlapping region B in which the first core wrap sheet 811 and the second core wrap sheet 812 overlap in the thickness direction Z, and that the sheet overlapping region B has a core wrap non-adhesion region 401 that exists along the entire length in the vertical direction X of the intermediate region M2, and that the non-skin side core wrap sheet 81 has a double-sided non-adhesion region C in which the core wrap non-adhesion region 401 and the central non-skin side core adhesive-free region 403 overlap in a plan view.

[0074] This configuration enhances the effect of suppressing twisting of the absorber 4 by easing internal forces during convex deformation in the central region 36. In other words, in the absorbent body 4, the double-sided non-adhesive region C is a region in plan view where the non-skin side core adhesive S1 and the non-skin side core wrap sheet adhesive Sd are absent. In the double-sided non-adhesive region C, both sides of the second core wrap sheet 812, which is located above (on the absorbent core side) the first core wrap sheet 811 in the sheet overlap region B, are regions that are not fixed (not adhered) anywhere. Therefore, when an external force directed inward in the lateral direction Y is applied to the absorbent body 4 during wear, the first and second core wrap sheets 811, 812 and the absorbent body 4 in the sheet overlap region B can be deformed to release the internal force in the double-sided non-adhesive region C, thereby promoting the effect of suppressing twisting of the absorbent body 4, especially the absorbent core 7, due to the relaxation of the internal force. Furthermore, even after the convex deformation of the central region 36 of the intermediate region M2, the first core wrap sheet 811 and the second core wrap sheet 812 overlap in the thickness direction Z, making it easier to maintain and sustain the convex shape of the absorbent core 7 with the double core wrap sheets (first core wrap sheet 811 and second core wrap sheet 812). In this way, the twisting of the absorber 4 can be further suppressed, and the convex deformation of the central region 36 in the intermediate region M2 can be more reliably maintained, thus ensuring a good fit in the intermediate region M2.

[0075] In napkin 1, the first and second core wrap sheets 811 and 812 are bonded together in the sheet overlapping region B by the non-skin side core wrap sheet adhesive Sd, so that the core wrap sheets do not curl up even under strong external force during wear. Moreover, in this embodiment, as shown in Figure 5, the bond is between the region including the lateral edge 812a of the second core wrap sheet 812 and the portion of the first core wrap sheet 811 that is laterally inward from the lateral edge 811a. In other words, the core wrap bonding region D in the sheet overlapping region B includes the region where the portion of the first core wrap sheet 811 that is laterally inward from the lateral edge 811a overlaps with the lateral edge 812a of the second core wrap sheet 812. Therefore, even when an external force directed inward in the lateral direction Y is applied relatively strongly from one side, the curling of the second core wrap sheet 812 is easily suppressed, and the space between the lateral edge 811a of the first core wrap sheet 811 and the adhesive Sd on the non-skin side of the core wrap sheet easily functions as an external force buffering region, which is effective in preventing unexpected deformation of the absorber 4. In addition, by providing the core wrap adhesive region D, the rigidity of the sheet overlap region B is increased, and the occurrence of twisting of the absorber 4 is further suppressed. The lateral edges 811a and 812a mentioned above are located in sheet overlapping region B. The phrase "laterally inward from the lateral edge 811a of the first core wrap sheet 811" refers to the area laterally inward from the lateral edge 811a of the first core wrap sheet 811, as viewed from the first core wrap sheet 811.

[0076] In the napkin 1 of this embodiment shown in Figure 5, the non-adherent core-wrap region 401 and the adherent core-wrap region D are located in the sheet overlap region B. However, as shown in the modified napkin 1A in Figure 7, the adherent core-wrap region D may not be located in the sheet overlap region B. In other words, the first core-wrap sheet 811 and the second core-wrap sheet 812 may not be adhered throughout the entire sheet overlap region B.

[0077] However, from the viewpoint of making it easier for the absorbent 4 to undergo convex deformation in the central region 36 of the intermediate region M2 and suppressing sheet curling in the sheet overlap region B, it is preferable that the sheet overlap region B, as in the napkin 1 of this embodiment, includes a core-wrap adhesive region D in addition to the core-wrap non-adhesion region 401. From the viewpoint of maintaining the convex deformation shape of the central region 36 well and effectively suppressing sheet curling, in a plan view, the ratio of the width of the core-wrap adhesive region D to the width of the core-wrap non-adhesive region 401 is preferably 0.8 or less, more preferably 0.6 or less, and the lower limit is preferably 0.2 or more, more preferably 0.3 or more. As specific numerical examples, the width of the core-wrap bonding area D is approximately 2.5 mm to 5.5 mm, and the width of the core-wrap non-bonding area 401 is approximately 7.5 mm to 10 mm. Note that these are not the only values ​​listed.

[0078] As shown in Figures 3 to 5, in the region where the absorbent material 4 in the intermediate region M2 exists, the non-skin side of the napkin 1 has a stiffness distribution in which a first low-rigidity region 21 is located at the center in the lateral direction Y, a pair of high-rigidity regions 20 are located on either side of the first low-rigidity region 21, and a pair of second low-rigidity regions 22 are located on either side of the pair of high-rigidity regions 20.

[0079] In other words, in the region where the absorber 4 exists in a plan view of the intermediate region M2, the region where the forward slip prevention portion 31 exists (regions other than the central region 36 and the outer region 37) includes an overlapping region where the forward slip prevention portion 31 and the non-skin side core adhesive S1 overlap in a plan view, resulting in a relatively high-rigidity region. On the other hand, the central region 36 and the outer region 37 do not include the above overlapping region and are low-rigidity regions with relatively lower rigidity than the region where the forward slip prevention portion 31 exists. The first low-rigidity region 21 and the second low-rigidity region 22 are regions where the forward-slip prevention portion 31 and the non-skin-side core adhesive S1 do not overlap in a plan view. The high-rigidity region 20 is a region where the forward-slip prevention portion 31 and the non-skin-side core adhesive S1 overlap in a plan view (overlapping region).

[0080] When an external force is applied to the intermediate area M2 in the crotch area of ​​the wearer in the lateral direction Y, a pair of high-rigidity regions 20 extending in the vertical direction X are provided, which improves resistance to twisting in the width direction (lateral direction Y), making it less likely to follow the deformation of the underwear, suppressing undesirable deformation of the absorbent core 7, and maintaining good liquid absorption of the absorbent core 7. Furthermore, in the intermediate region M2, the central region 36 forms a first low-rigidity region 21 that extends in the vertical direction X, which is preferentially deformable due to its low rigidity. As a result, the central region 36 deforms convexly toward the wearer's excretory area, making it easier to fit the wearer's groin shape. Moreover, in the region where the absorbent 4 exists in a plan view of the intermediate region M2, the pair of outer regions 37 form a pair of second low-rigidity regions 22 that extend in the vertical direction X, which is preferentially deformable due to its low rigidity, making it easier to fit the wearer's groin. In addition, in the intermediate region M2, the region lateral Y-outside of the absorbent 4 has lower rigidity than the region where the absorbent 4 exists because the absorbent 4 is absent. The regions located on both sides of the pair of second low-rigidity regions 22 (regions where the absorbent is absent) also become low-rigidity regions, and these low-rigidity regions, along with the pair of second low-rigidity regions 22, also make it easier to fit the groin.

[0081] Thus, napkin 1 achieves both improved resistance to shifting of the absorbent material 4 during wear and a good fit.

[0082] <Further detailed composition of absorbent material> [Absorbent core] From the viewpoint of further enhancing resistance to twisting and improving the effect of a good fit, it is preferable that the absorbent core 7 is provided with a rigidity change portion extending in the lateral direction Y, and that this rigidity change portion is located in the front region M31 (see Figure 1) when the rear region M3 of the napkin 1 is divided in half in the longitudinal direction X. The rigidity change portion is the part in which the rigidity of the absorbent core 7 changes when viewed along the longitudinal direction X.

[0083] By providing a rigidity change section, when worn, the intermediate region M2 (more specifically, the region in front of the rigidity change section 73) becomes less able to follow the deformation of the rear region M3 (more specifically, the deformation occurring in the region behind the rigidity change section 73). As a result, the absorber 4 becomes less prone to twisting, making it easier to maintain a good fit.

[0084] In the napkin 1 of this embodiment, the absorbent core 7 has regions in which the basis weight and thickness of the fibrous material (constituent material) constituting the absorbent core 7 differ from each other, and the boundary between these regions with different basis weights functions as a rigidity change region. Regions with relatively higher basis weights are thicker and more rigid than regions with relatively lower basis weights. This will be explained below.

[0085] Furthermore, a rigidity change section may be formed by compression processing such as embossing. That is, a relatively high-density region may be formed by compression processing, and a rigidity change section may be formed by utilizing the difference in rigidity between the high-density region and a relatively low-density region that has not undergone compression processing. Even with a rigidity change section of this form, the intermediate region M2 (more specifically, the region in front of the rigidity change section) becomes less able to follow the deformation of the rear region M3 (more specifically, the deformation occurring in the region behind the rigidity change section) due to the presence of the rigidity change section, making the absorber 4 less prone to twisting and easier to maintain a good fit.

[0086] However, from the viewpoint of ensuring the flexibility of the napkin 1 and ensuring a good wearing experience, it is preferable to form a rigidity change section by providing regions with different basis weights of the fiber material of the absorbent core, as in the napkin 1 of this embodiment, rather than using compression processing.

[0087] In napkin 1, as shown in Figure 6, the absorbent core 7 has a low basis weight section 70, a front high basis weight section 71, and a rear high basis weight section 72. The low basis weight section 70 is a region where the basis weight of the fiber material constituting the absorbent core is lower and the rigidity is lower than that of the front high basis weight section 71 and the rear high basis weight section 72. As shown in Figures 3 and 4, typically the low basis weight section 70 is thinner than that of the front high basis weight section 71 and the rear high basis weight section 72. In napkin 1, the absorbent core 7 is arranged such that the front high basis weight section 71 and the rear high basis weight section 72 protrude toward the non-skin side. In this embodiment, the "low basis weight section" means a region where the basis weight is 70% or less of that of the "high basis weight section," and it is preferable that it includes a region where the basis weight is 60% or less. In this case, as in this embodiment, if the low basis weight section includes a groove with a lower basis weight than the surrounding area, the basis weight of the portion other than the groove is considered to be the basis weight of the "low basis weight section." Furthermore, if a low-basis-weight groove or similar structure is located within a high-basis-weight section, the entire area is referred to as the high-basis-weight section, but the basis weight of the portion excluding the groove is considered the basis weight of the "high-basis-weight section." The front high-basis-weight section 71 and the rear high-basis-weight section 72 are spaced apart in the vertical direction X. The spaced-apart region 75 of the absorbent core 7, located between the front high-basis-weight section 71 and the rear high-basis-weight section 72, is composed of a low-basis-weight section 70. In Figure 6, the front high-basis-weight section 71 and the rear high-basis-weight section 72, which have relatively high basis weight, are shown with dots, while the low-basis-weight section 70, which has a lower basis weight, is shown as a plain color without any patterns such as dots.

[0088] As shown in Figure 6, the front high-basis-weight section 71 is provided in a shape that is continuous in the vertical direction X, extending over a part of the front area M1, the intermediate area M2, and a part of the rear area M3. The front high-basis-weight section 71 has a shape that combines a vertically elongated, roughly rounded rectangle-shaped central part that is long in the vertical direction X, and bulging parts that bulge outward in the horizontal direction Y from each of the two side edges of the central part along the vertical direction X.

[0089] In the napkin 1 of this embodiment, the front high basis weight portion 71 is arranged over the entire lateral Y area of ​​the absorbent core 7. As a result, the napkin 1 increases the amount of liquid absorbed in the intermediate region M2 (region opposite the excretion area) to which a large amount of liquid from the wearer is supplied, making it easier to suppress leakage, and also makes it easier to suppress the occurrence of undesirable deformation in the intermediate region M2. On the other hand, the high rigidity of the front high-basis-weight section 71 is arranged over the entire lateral Y area, which tends to increase the rigidity of the absorbent side section 46 of the absorbent 4 in the intermediate M2 area. However, in the napkin 1 of this embodiment, by using the above configuration (a), the rigidity of the absorbent side section 46 does not become excessively high, and the napkin 1 can be gently fitted to the groin area.

[0090] The rear high-basis-weight section 72 is located at the center of the rear area M3 in the lateral direction Y. The rear high-basis-weight section 72 is located further rearward in the vertical direction X than the front high-basis-weight section 71, and is spaced apart from the front high-basis-weight section 71. When worn, the front high-weight portion 71 is positioned opposite the excretory portion (vaginal opening), the rear high-weight portion 72 is positioned opposite the gluteal cleft, and there is a separated region 75 consisting of a low-weight portion 70, which allows the napkin 1 to easily deform to conform to the shape of the body so as to wrap around the buttocks in the vertical direction. Furthermore, in the napkin 1, the rear high-basis-weight section 72 is provided at the center of the lateral Y direction, and the hip guard H, which lacks the low-basis-weight section 70 and the absorbent material 4, is positioned on both sides thereof, making it easier to deform the napkin 1 to wrap around the left and right curves of the buttocks from the left and right directions.

[0091] In the absorbent core 7, the low basis weight section 70 is provided in areas other than the front high basis weight section 71 and the rear high basis weight section 72. The low basis weight section 70 is provided in the front area M1, the middle area M2, and the rear area M3 of the napkin 1. The low basis weight section 70 is provided in the front and rear in the vertical direction X of the front high basis weight section 71 and is positioned to surround the rear high basis weight section 72.

[0092] In the napkin 1 of this embodiment, the boundary between the front high basis weight section 71 and the low basis weight section 70 located immediately behind the front high basis weight section 71 functions as a rigidity change section 73. In Figure 6, the rigidity change section 73 is shown by a thick solid line. As shown in Figure 6, in the napkin 1 of this embodiment, the rigidity change section 73 extends in the lateral direction Y across the entire lateral Y region of the absorbent core 7 and is located across a part of the intermediate region M2 and a part of the rear region M3. In the rear region M3, the rigidity change section 73 is located in the region M31 in front of the horizontal line L1, which is drawn to bisect the rear region M3 of the napkin 1 in the vertical direction X, and is not located behind the horizontal line L1.

[0093] Furthermore, grooves with a lower basis weight and thinner thickness than the low basis weight section 70 may be provided at the boundary between the low basis weight section 70 and the front high basis weight section 71, and at the boundary between the low basis weight section 70 and the rear high basis weight section 72. In that case, the boundary is between the high basis weight sections 71 and 72 and the grooves.

[0094] Furthermore, as shown in Figure 4, in napkin 1, the high basis weight sections 71 and 72 are thicker than the low basis weight section 70. The absorbent core 7 has a shape in which the basis weight changes abruptly at the boundary between the low basis weight section 70 and the front high basis weight section 71 (in other words, the thickness changes abruptly), and the side surface 7c of the front high basis weight section 71 (see Figure 6) rises steeply (preferably almost perpendicular) to the non-skin side surface of the low basis weight section 70. Note that in Figure 4, the boundary between the front high basis weight section 71 and the low basis weight section 70 and the rounded compressed section 6 roughly overlap. For this reason, in Figure 4, the portion of the non-skin side of the low basis weight section 70 that is close to the rounded compressed section 6 is pushed downward by the rounded compressed section 6 which is concave downwards, and slopes gently with respect to the XY plane, connecting to the side surface 7c of the front high basis weight section 71, as schematically illustrated. The rigidity change section 73 is a part where the basis weight changes abruptly, and is the part where the side surface 7c of the front high basis weight section 71 and the non-skin side surface of the low basis weight section 70 come into contact. In contrast, the absorbent core 7 may have a configuration in which the basis weight changes smoothly from the front high basis weight section 71 to the low basis weight section 70, and the side surface 7c of the front high basis weight section 71 is positioned diagonally to the non-skin side surface of the low basis weight section 70. In this case as well, the rigidity change section 73 is the part where the side surface 7c of the front high basis weight section 71 and the non-skin side surface of the low basis weight section 70 are in contact, and this part is called the boundary between the front high basis weight section 71 and the low basis weight section 70. In napkin 1, the shape of the absorbent core 7 was such that the non-skin sides of the high-basis-weight sections 71 and 72 protruded further towards the non-skin side than the non-skin side of the low-basis-weight section 70. However, instead, the skin-sides of the high-basis-weight sections 71 and 72 may protrude further towards the skin than the skin-side of the low-basis-weight section 70. In this case, the rigidity change section 73 is the part where the side 7c of the front high-basis-weight section 71 and the skin-side of the low-basis-weight section 70 come into contact.

[0095] The front high basis weight section 71 and the rear high basis weight section 72 are regions where the basis weight of the constituent fibers of the absorbent 4 is higher and the rigidity is higher than that of the low basis weight section 70. By providing the highly rigid front high basis weight section 71 opposite the excretion section, the intermediate region M2 of the main body M is less prone to unintended deformation, the liquid absorption capacity of liquids from the excretion section can be maintained well, and the amount of liquid that can be absorbed can be increased. Furthermore, by providing a highly rigid, high-basis-weight rear section 72 against hip cracks, the rear region M3 of the main body M is less prone to unintended deformation, which helps maintain good liquid absorption of liquids flowing towards the rear of the napkin 1, and also increases the amount of liquid absorbed by the napkin 1. Furthermore, typically, the front high-basis-weight section 71 and the rear high-basis-weight section 72 are thicker and protrude more than the low-basis-weight section 70. The front high-basis-weight section 71 and the rear high-basis-weight section 72 improve the fit of the napkin 1 in the excretory area and buttock cleft, effectively suppressing leakage.

[0096] In the napkin 1 of this embodiment, a rigidity change portion 73 extending in the lateral direction Y is provided in the absorbent core 7, and a portion where a difference in rigidity occurs in the front and rear in the vertical direction X is formed in the absorbent core 7. As a result, deformation occurring in the rear region M3 during wear (specifically, deformation occurring mainly in the low-rigidity, low-basis-weight portion 70 located behind the rigidity change portion 73) is less likely to propagate to the intermediate region M2 (specifically, the high-rigidity, front high-basis-weight portion 71 located in front of the rigidity change portion 73), further reducing twisting of the absorbent material 4 in the intermediate region M2 and making it easier to maintain a good fit.

[0097] In addition, in the napkin 1 of this embodiment, as shown in Figures 2 and 5, the stiffness change portion 73 extends in the lateral direction Y across the entire lateral direction Y of the absorbent core 7. More specifically, as shown in Figure 6, the stiffness change portion 73 has a convex shape that is convex in the vertical direction X backward, extending diagonally backward from each of the lateral Y side edges 7s of the absorbent core 7 toward the vertical center line CL. The top of the convex shape of the stiffness change portion 73 is denoted by the numeral 73a. In the napkin 1, in a plan view, the top of the convex shape 73a of the stiffness change portion 73 is located in the non-adhesive region C on both sides.

[0098] This configuration allows for the propagation of deformation occurring in the rear region M3 (specifically, deformation occurring mainly in the low-rigidity, low-basis-weight section 70 located behind the rigidity change section 73) to the intermediate region M2 (specifically, the high-rigidity, high-basis-weight section 71 located in front of the rigidity change section 73) across the entire lateral Y region. In addition, in a plan view, the top 73a of the convex-shaped rigidity change section 73, which is convex towards the rear, is located in the double-sided non-adhesive region C. This allows the length of the high-rigidity, high-basis-weight section 71, which can exert the effect of suppressing the propagation of deformation occurring in the rear region M3 to the intermediate region M2, to be made as long as possible in the vertical X direction. As a result, in the intermediate region M2, the central region 36 is less affected by the deformation in the rear region M3, and convex deformation toward the excretion section is more likely to occur.

[0099] [Round pressing section, first lateral pressing section] As shown in Figure 1, the surface sheet 2 may have a round compression section 6 and a first lateral compression section 12 formed thereon. As shown in Figures 3 and 4, the round compression section 6 and the first lateral compression section 12 are formed as linear grooves that are integrally compressed between the surface sheet 2 and the absorbent material 4 and the back sheet 3, and that are recessed toward the back sheet 3. As shown in Figures 3 and 4, the round compression section 6 and the first lateral compression section 12 are recesses that are recessed to reach the non-skin side core wrap sheet 81. As shown in Figure 1, the round compression section 6 and the first lateral compression section 12 are formed in the area of ​​the skin side (upper surface) of the surface sheet 2 that is not covered by the side sheet 5. The round compression section 6 is configured to encircle the main body M. Furthermore, the term "linear groove" includes both a form in which the compressed sections extend continuously to form a linear shape, and a form in which multiple compressed sections are intermittently arranged and can be considered as a single linear groove overall. In the case of a linear groove, "extending in the vertical direction X" or "extending in the horizontal direction Y" means that the entire structure extends in the vertical direction X or horizontal direction Y, and includes forms in which a part is curved. The same applies to the rear compressed section 13 described later. The compressed section is a high-rigidity region that is compacted by compression and has higher rigidity compared to the uncompressed region.

[0100] As shown in Figure 1, the round compression section 6 has a pair of left and right vertical compression sections 61 extending in the vertical direction X, and a front lateral compression section 62 and a rear lateral compression section 63 extending in the lateral direction Y. The pair of vertical compression sections 61 are provided along almost the entire length of the main body M, from the front area M1 through the intermediate area M2 to the rear area M3. The front lateral compression section 62 connects the front ends of each of the pair of vertical compression sections 61. The rear lateral compression section 63 connects the rear ends of each of the pair of vertical compression sections 61.

[0101] The first lateral compression section 12 is located in the rear region M3 and extends in the lateral direction Y. The first lateral compression section 12 is located behind the front high-basis-weight section 71 provided in the absorbent core 7 and has a rearward-convex arc shape that substantially follows the shape of the rear edge of the front high-basis-weight section 71. The first lateral compression section 12 is shaped to connect with the vicinity of the center in the longitudinal direction X of each of the pair of longitudinal compression sections 61.

[0102] As shown in Figure 4, in napkin 1, the rigidity change portion 73 (boundary between the front high basis weight portion 71 and the low basis weight portion 70) is preferably located on the non-skin side 7a of the absorbent core 7, and the round compression portion 6 as a recess is preferably recessed downward in the thickness direction Z so as to reach the non-skin side core wrap sheet 81. Furthermore, as shown in Figure 1, in napkin 1, it is preferable that the round compression portion 6 as a recess straddles the rigidity change portion 73 in the longitudinal direction X in a region that overlaps with the front anti-slip portion 31 in a plan view. In other words, it is preferable that the round compression portion 6 is arranged to traverse the rigidity change portion 73 in the longitudinal direction X from the front high basis weight portion 71, which is located in the longitudinal direction X forward of the rigidity change portion 73, to the low basis weight portion 70, which is located in the longitudinal direction X backward of the rigidity change portion 73, in a region that overlaps with the front anti-slip portion 31 in a plan view.

[0103] In this way, by positioning the rigidity change portion 73 on the non-skin side 7a of the absorbent core 7, the rigidity change portion 73 can be positioned away from the skin side 7b where liquid from the wearer is absorbed, making it easier to maintain the shape of the rigidity change portion 73 and its vicinity even after liquid absorption. This makes it easier to sustain the effect of suppressing the propagation of deformation in the rear region M3 to the intermediate region M2 by providing the rigidity change portion 73.

[0104] On the other hand, if the rigidity change portion 73 is placed on the non-skin side 7a of the absorbent core 7, a gap is likely to occur between the absorbent core 7 and the non-skin side core wrap sheet 81 due to the step formed by the front high basis weight portion 71 and the low basis weight portion 70.

[0105] However, in the napkin 1 of this embodiment, as shown in Figure 1, in the intermediate region M2, the longitudinal compression portion 61 of the round compression portion 6 is provided in a region where the forward slip prevention portion 31 and the non-skin side core adhesive S1 overlap in a plan view, and as shown in Figure 4, the round compression portion 6 is provided so as to reach the non-skin side core wrap sheet 81. Furthermore, in the region where it overlaps with the forward slip prevention portion 31 in a plan view, the round compression portion 6 is arranged to traverse vertically in the longitudinal direction X through the rigidity change portion 73. As a result, as shown in Figure 4, the rigidity change portion 73 of the absorbent core 7 and its vicinity can be adhered to the non-skin side core wrap sheet 81, the occurrence of gaps between the absorbent core 7 and the non-skin side core wrap sheet 81 is suppressed, and the resistance of the absorbent body 4 to twisting in the region where the forward slip prevention portion 31 is present is improved. From the viewpoint of reliably bonding the rigidity change portion 73 of the absorbent core 7 and its vicinity with the non-skin side core wrap sheet 81, it is preferable that in the intermediate region M2, the non-skin side core adhesive S1 is located laterally outward in the Y direction from the round compression portion 6 in a plan view.

[0106] [Rear compression section] As shown in Figure 1, the surface sheet 2 may have a rear compression section 13 in the rear region M3. The rear compression section 13 is located in the area from the rear end 32b of the rear anti-slip section 32, which is the rearmost anti-slip section in the longitudinal direction X of the napkin 1, to the rear end 1b of the napkin 1. The rear end 32b of the rear anti-slip section 32 is the last end of the anti-slip section located on the main body M. The rear compression section 13 is formed by integrally compressing the surface sheet 2 and the absorbent material 4 to the back sheet 3 side. The rear compression section 13 is a recess that extends to the non-skin side core wrap sheet 81, similar to the round compression section 6 and the first lateral compression section 12. The rear compression section 13 extends in the lateral direction Y and is an arc shape that is convex toward the front. The rear compression section 13 is located in the central part 45 of the absorbent material so as to cross the longitudinal center line CL. In plan view, the rear compression section 13 overlaps with the non-skin side core adhesive S1. More specifically, the rear compression portion 13 extending in the lateral direction Y overlaps with the non-skin side core adhesive S1 in a plan view on both sides in the lateral direction Y, but does not overlap with the non-skin side core adhesive S1 in a plan view on the central part in the lateral direction Y.

[0107] The rear compression portion 13 reaches the non-skin side core wrap sheet 81 and partially overlaps with the non-skin side core adhesive S1 in a plan view. In this overlapping portion, the non-skin side core wrap sheet 81 and the absorbent core 7 can be firmly bonded. This makes it less likely for gaps to form between the non-skin side core wrap sheet 81 and the absorbent core 7, further suppressing twisting of the absorbent body 4.

[0108] Here, in the napkin 1, the area where the rear compression portion 13 is located (the area from the rear end 32b of the rear anti-slip portion 32 to the rear end 1b of the napkin 1) is an area where the anti-slip portion does not exist, an area where the napkin 1 is not adhered to the underwear when worn, and an area where the absorbent material 4 is present in plan view. By providing the rear compression portion 13 in such an area, which reaches the non-skin side core wrap sheet 81 and overlaps with the non-skin side core adhesive S1 in plan view, it is possible to suppress the twisting of the absorbent material 4 that is likely to occur in the area not adhered to the underwear, and maintain a good fit.

[0109] [Skin-side core adhesive] As shown in Figures 3 and 4 of this embodiment, it is preferable that a skin-side core adhesive S2 is provided to bond the absorbent core 7 and the skin-side core wrap sheet 82.

[0110] The skin-side core adhesive S2 is present over at least the entire length of the intermediate region M2 in the longitudinal direction X, and in napkin 1, it is provided continuously in the longitudinal direction X over almost the entire length of the absorbent core 7 in the longitudinal direction X. As shown in Figures 3 and 4, the skin-side core adhesive S2 is applied to form a coating area that is continuous in the transverse direction Y. The transverse Y side edges S2s of the skin-side core adhesive S2 overlap with the outer region 37 in a plan view.

[0111] In napkin 1, the non-skin side core adhesive S1 is present over the entire length of the longitudinal X direction of at least the intermediate region M2. As described above, the non-skin side core adhesive S1 is applied so as to provide a pair of non-skin side core adhesive coated areas A10 that are spaced apart in the transverse Y direction. In other words, the non-skin side core adhesive S1 is applied so as to be an intermittent coated area in the transverse Y direction. As shown in Figures 3 and 4, both transverse Y side edges S1s of the entire non-skin side core adhesive coated area A1 overlap with the outer region 37 in a plan view.

[0112] As shown in Figures 3 and 4, the pair of side edges S2s of the skin-side core adhesive S2 are positioned laterally inward in the Y direction compared to the pair of side edges S1s of the non-skin-side core adhesive S1. This configuration reduces discomfort in the groin area while maintaining a good fit. In other words, by positioning the pair of side edges S2s of the non-skin-side core adhesive S1, which are located closer to the wearer's skin than the non-skin-side core adhesive S1, inward in the lateral direction Y compared to the pair of side edges S1s of the non-skin-side core adhesive S1, the rigidity of the skin-side (upper) of the absorbent lateral portion 46 can be reduced, thereby reducing discomfort when worn in the groin area. At the same time, the rigidity of the non-skin-side (lower) of the absorbent lateral portion 46 can be increased to firmly fix the napkin 1 to the underwear, making the napkin less likely to bunch up and maintaining a good fit.

[0113] [Positional relationship between the non-skin core adhesive and the intermittent region] As shown in Figure 2, for napkin 1, it is preferable that the non-skin side core adhesive S1 overlaps with the intermittent region 35 in a plan view, at least in part.

[0114] The intermittent region 35 is located in the posterior region M3, and there is no anti-slip portion in this region, so it does not adhere to the underwear when worn. Therefore, in the intermittent region 35 of the napkin 1, the napkin 1 does not follow the deformation of the underwear, and the deformation of the napkin 1 that follows the deformation of the underwear in the part of the posterior region M3 behind the intermittent region 35 is less likely to propagate to the intermediate region M2 which is in front of the intermittent region 35, thus making it easier to suppress twisting in the intermediate region M2. In addition, by placing the intermittent region 35, in which the napkin 1 does not follow the deformation of the underwear, behind the rigidity change portion 73 of the posterior region M3, it becomes easier to fit the posterior region M3 of the napkin 1 to the buttocks, which have a high curvature. On the other hand, in the intermittent region 35 of the napkin 1, the absorbent material 4 is prone to bunching because it is not adhered to the underwear. However, the non-skin side core adhesive S1 overlaps the intermittent region 35 in a plan view, increasing its rigidity. This makes it less likely for undesirable deformations such as bunching to occur in the intermittent region 35 of the main body M even when external force is applied to the napkin 1 due to vigorous movements by the wearer, thus making it easier to maintain a good fit.

[0115] Furthermore, from the viewpoint of suppressing undesirable deformation of the area corresponding to the intermittent region 35 of the napkin 1, as shown in Figure 2, a rear high-basis-weight portion 72 with relatively high basis weight and high rigidity may be present in the area corresponding to the intermittent region 35 of the napkin 1. In the napkin 1, the area corresponding to the intermittent region 35 tends to have low rigidity due to the absence of a slip-prevention portion, but the rigidity can be increased by providing the rear high-basis-weight portion 72, making it less likely for undesirable deformation to occur in the area corresponding to the intermittent region 35 of the napkin 1, and making it easier to maintain a good fit.

[0116] [Examples of dimensions for each configuration] The following are examples of dimensions for each configuration, but they are not exhaustive. The dimensions of each component can be appropriately set based on the length of napkin 1 (length in the vertical direction X), the length and width of absorbent material 4, etc., but the numerical examples described below are preferred for napkins with a length of 290 mm to 450 mm. In this napkin, the length of absorbent material 4 is preferably 300 mm to 330 mm, and the width of absorbent material 4 is preferably 65 mm to 75 mm. In napkin 1, the length of absorbent material 4 is 316 mm and the width is 73 mm.

[0117] (Example dimensions for the anti-slip section) The vertical width of the front anti-slip portion 31 is preferably 150 mm to 210 mm, and the horizontal width is preferably 10 mm to 30 mm. In napkin 1, the horizontal width of the front anti-slip portion 31 is 20 mm. The distance between the pair of forward-preventing portions 31 in the lateral direction Y is preferably 5 mm to 20 mm, and in the case of napkin 1 it is 10 mm. The position of the rear end 31a of the front anti-slip portion 31, which defines the front position of the intermittent region 35, is preferably located 30 mm to 125 mm behind the excretion point. The excretion point is the center position of the longitudinal X length of the wing W. The vertical width of the front anti-slip portion 31 located in the rear region M3 is preferably 10 mm to 85 mm, which is 40 mm for napkin 1, from the viewpoint of ensuring good liquid absorption and positioning the intermittent region 35 near the anus.

[0118] The distance in the vertical direction X between the rear end 31a of the front anti-slip portion 31 and the front end 32a of the rear anti-slip portion 32, that is, the vertical width of the intermittent region 35, is 25 mm to 35 mm, and in the case of napkin 1, it is 30 mm, from the viewpoint of effectively reducing the force exerted on the intermediate region M2 by the deformation of the rear region M3 of the napkin 1 that follows the deformation of the underwear during the wearer's movements.

[0119] The vertical width of the rear anti-slip portion 32 is preferably 10 mm to 45 mm, which is 27 mm for napkin 1, and the horizontal width is preferably 10 mm to 30 mm, which is 20 mm for napkin 1. The horizontal distance Y between the pair of rear anti-slip portions 32 is preferably 5 mm to 20 mm, which is 10 mm for napkin 1.

[0120] (Example dimensions of non-skin-side core adhesive S1 and skin-side core adhesive S2) The non-skin-side core adhesive coating area A10, which is the area coated with the non-skin-side core adhesive S1, preferably has a vertical width of 120 mm to 450 mm and a horizontal width of 25 mm to 35 mm. In napkin 1, the vertical width of the non-skin-side core adhesive coating area A10 is 315 ± 5 mm and the horizontal width is 31 ± 3 mm. The horizontal distance Y between a pair of non-skin-side core adhesive coating areas A10 is preferably 2 mm to 10 mm, and in napkin 1 it is 5 mm. The width of the entire non-skin side core adhesive coating area A1 (corresponding to the distance between the two lateral Y edges S1s) is preferably 55 mm or more and 70 mm or less, and for napkin 1 it is 67 ± 3 mm. In the absorbent material 4, the distance between the side edge S1s of the entire non-skin side core adhesive coating area A1 and the side edge 4s of the absorbent material 4 in a plan view is preferably 1 mm to 5 mm, and in the case of napkin 1, it is 2.5 ± 0.5 mm.

[0121] The skin-side core adhesive coating area A2, which is the area where the skin-side core adhesive S2 is applied, preferably has a vertical width of 120 mm to 450 mm and a horizontal width (corresponding to the distance between the two side edges S2s in the horizontal direction S2) of 45 mm to 65 mm. In napkin 1, the vertical width of the skin-side core adhesive coating area A2 is 315 ± 5 mm and the horizontal width is 62 ± 0.5 mm.

[0122] (Example of dimensions for overlapping sheet areas) From the viewpoint of preventing the core wrap sheet from peeling off and improving the shape retention of the absorbent core, the width of the sheet overlapping area B is preferably 5 mm to 30 mm, and is 15 mm for napkin 1. From the viewpoint of promoting the effect of suppressing twisting of the absorbent material 4 by easing internal forces, the width of the double-sided non-adhesive region C is preferably 2 mm or more and 15 mm or less, and in the case of napkin 1 it is 5 mm.

[0123] (Area ratio of adhesive on the non-skin side of the core) The following is an example of the area ratio of the non-skin side core adhesive in each of the left and right regions, which are divided by the vertical center line CL that bisects the absorber 4 in the horizontal direction Y, in the region where the absorber 4 of the intermediate region M2 exists in a plan view.

[0124] In napkin 1, in the region where the absorbent material 4 in the intermediate region M2 is located in a plan view, in the left and right regions separated by the vertical center line CL, the area ratio of the non-skin side core adhesive S1 in the intermediate region M2 is higher in the region where the anti-slip portion (forward anti-slip portion 31) is located than in the central region 36 and the outer region 37. In the cross-sectional view shown in Figure 5, the area ratio of the non-skin side core adhesive S1 is such that the first central region 361 (second central region 362) and the first outer region 371 (second outer region 372) < the region where the forward anti-slip portion 31 is located. In particular, it is preferable that the area where the first central region 361 (second central region 362) < first outer region 371 (second outer region 372) < anterior slip-prevention portion 31 exists is such that when a strong force is applied from the thigh in the lateral direction Y inward, the first and second central regions 361 and 362 can easily deform appropriately toward the skin in the thickness direction, improving the fit to the wearer, and also acting more easily as a buffering area for the external force mentioned above, thus contributing to the resistance of the entire absorbent material to twisting.

[0125] Furthermore, the ratio of the area ratio of the non-skin side core adhesive S1 in each of the first and second central regions 361, 362 and the region where the forward slip-preventing portion 31 exists is preferably 0.5 or less, more preferably 0.3 or less, and the lower limit should be 0 or greater, in order to achieve a high level of both resistance to twisting of the absorber and fit in the intermediate region M2 in the vertical direction X. Furthermore, the ratio of the area ratio of the non-skin side core adhesive S1 in each of the first and second outer regions 371, 372 and the region where the anterior slip-preventing portion 31 exists is preferably 0.7 or less, more preferably 0.5 or less, and preferably 0.1 or more, in terms of former / latter, from the viewpoint of achieving both resistance to twisting of the absorber in the longitudinal intermediate region and fit, even when a strong force is applied from the thigh toward the lateral direction Y inward.

[0126] From the viewpoint of ensuring that the central region 36 of the absorbent material 4 is properly convex towards the excretion area when worn, the area ratio of the non-skin side core adhesive S1 in the first central region 361 (second central region 362) in the intermediate region M2 is preferably 0 to 30%, and more preferably 15% or less. The area ratio of the non-skin side core adhesive S1 in the first central region 361 (second central region 362) is determined by dividing the area of ​​the coated area of ​​the non-skin side core adhesive S1 that overlaps the first central region 361 (second central region 362) in a plan view in the intermediate region M2 by the area of ​​the first central region 361 (second central region 362), and then multiplying by 100. As a specific numerical example, in the example shown in Figure 5, there is no non-skin side core adhesive S1 that bonds the second core wrap sheet 812 and the absorbent core 7 in the first central region 361, so the area ratio of the non-skin side core adhesive S1 in the first central region 361 is 0%.

[0127] When worn, in order to ensure that the absorbent material 4 fits well to the groin area while effectively suppressing twisting, the area ratio of the non-skin side core adhesive S1 in the first outer region 371 (second outer region 372) in the intermediate region M2 is preferably 15 to 70%, and more preferably 30 to 50%. The area ratio of the non-skin side core adhesive S1 in the first outer region 371 (second outer region 372) is determined by dividing the area of ​​the coated area of ​​the non-skin side core adhesive S1 that overlaps the first outer region 371 (second outer region 372) in a plan view in the intermediate region M2 by the area of ​​the first outer region 371 (second outer region 372), and then multiplying by 100. As a specific numerical example, the width of the first outer region 371 (second outer region 372) is 12.5 mm, the width of the coating area of ​​the non-skin side core adhesive S1 that overlaps with the first outer region 371 (second outer region 372) in a plan view is 7 mm, and the area ratio of the non-skin side core adhesive S1 in the first outer region 371 (second outer region 372) is 56%.

[0128] From the viewpoint of effectively suppressing twisting of the absorbent 4, in the intermediate region M2, the area ratio of the non-skin side core adhesive S1 in the region where the forward slip-preventing portion 31 exists is preferably 70% or more, and more preferably 100%. The area ratio of the non-skin side core adhesive S1 in the region where the forward slip prevention portion 31 exists is calculated for each forward slip prevention portion 31 located in the intermediate region M2 by dividing the area of ​​the coating region of the non-skin side core adhesive S1 that overlaps the forward slip prevention portion 31 in a plan view by the area of ​​the forward slip prevention portion 31, and then multiplying by 100.

[0129] <Other Embodiments> Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the present invention.

[0130] The absorbent articles to which the present invention can be applied are not limited to sanitary napkins. Specifically, the present invention can be applied to pad-type absorbent articles similar to sanitary napkins, such as urine pads and panty liners.

[0131] Furthermore, although the above-described embodiment uses a napkin equipped with wings W and a hip guard H as an example, the present invention can also be applied to napkins that do not have wings W and / or a hip guard H.

[0132] <Examples> The napkin 1 shown in Figure 1, which is an example of the present invention, and the napkin of a comparative example were evaluated for their resistance to bunching and compression in the crotch area.

[0133] As the napkin of the example, a napkin 1 having the configuration (i) described in the above embodiment was prepared. As a comparative example napkin, a napkin without configuration A was prepared by changing the coating pattern of the non-skin side core adhesive S1, which is placed between the absorbent core and the non-skin side core wrap sheet, from that of napkin 1. The comparative example napkin was prepared in the same manner as napkin 1 of the example, except that the coating pattern of the non-skin side core adhesive S1 was different. In the comparative example napkin, the non-skin side core adhesive S1 was coated in a striped pattern at equal intervals across the entire area between the absorbent core and the non-skin side core wrap sheet. In other words, in the comparative example napkin, the area ratio of the non-skin side core adhesive S1 is equal between the central and outer regions where there is no anti-slip portion and the region where the front anti-slip portion 31 is present.

[0134] [Method for evaluating resistance to wrinkling] The resistance to twisting of the napkins in the examples and comparative examples was evaluated using the dynamic twisting rate, described below, as an indicator. The results are shown in Table 1 below.

[0135] The napkins of the examples and comparative examples were used as measurement samples, and the dynamic twist rate of the measurement samples was evaluated using a driven female lower body human model. First, the width of the middle section M2 (area opposite the excretory area) of the sanitary napkin to be evaluated (width before walking) was measured. The napkin was then attached to the panties, placed on a flat surface, 3g of water was injected into the central section 36, and then it was attached to a female body model. Next, a human body model was made to walk at a speed of 100 steps / minute for 20 minutes. During the model's walking, 1.5g of defiberized horse blood was injected into a sanitary napkin that was still attached to the model after 3 minutes of walking, repeating this process 6 times, for a total of 9g of defiberized horse blood being injected into the napkin. The napkin was then removed from the underwear, and its width in the middle M2 region (width after walking) was measured. The dynamic twist rate (%) was calculated from the width before and after walking using the following formula. A smaller dynamic twist rate indicates that the napkin is less prone to twisting, resulting in a higher rating. The defibrous horse blood used here is defibrous horse blood manufactured by Nippon Biotest Co., Ltd., and its viscosity at a liquid temperature of 25°C is adjusted to 8 cp. This viscosity was measured using a TVB-10M viscometer manufactured by Toki Sangyo Co., Ltd., with a rotor named L / AdP (rotor code 19) at a rotation speed of 12 rpm. Dynamic wobble rate = [{(Width of the mid-section before walking) - (Width of the mid-section after walking)} ÷ (Width of the mid-section before walking)] × 100

[0136] [Method for measuring compression load in the groin area] To evaluate the contact load exerted on the wearer by each of the example and comparative example napkins, the crotch compression load (width compression load) of each napkin was measured. The crotch compression load is the lateral (width) compression load of the measured napkin (absorbent material), and corresponds to the contact load exerted on the wearer by the napkin when a lateral external force is applied to the napkin from the wearer's thighs during wear. The crotch compression load serves as an indicator of the lateral flexibility of the napkin or its absorbent component. The smaller the value of the crotch compression load, the more flexible the napkin is, the less likely it is to wrinkle during wear, the less discomfort in the groin area, and the better the wearing experience, resulting in a higher evaluation.

[0137] Figure 8 shows an overview of the method for measuring the compression load in the groin area. The measuring equipment used was the TENSILON RTC-1210S (measuring device K) manufactured by Orientec Co., Ltd., and a jig J. The jig J has a pair of arcs J11 and J12 that apply a compression load to the groin area of ​​the measurement sample 100 (napkin), and a pulley J2 that pulls a string J3 attached to one of the arcs J11. When the napkin used as measurement sample 100 had an extension portion that extended laterally outward in the Y direction from the main body, such as a wing or hip guard, tissue paper was attached to the entire surface of the anti-slip portion of the backing sheet on the main body of the napkin, and the extension portion was folded back towards the backing sheet to form measurement sample 100. At this time, the width of measurement sample 100 was adjusted to be the same as the width of the core wrap sheet, which is a component of measurement sample 100. As shown in Figure 8(a), the measurement sample 100 was positioned below the fixing string J4 such that the intermediate area M2 (area facing the excretion area) was at the same horizontal position as the vertices of the pair of arcs J11 and J12 of the jig J, and was in contact with the arc J12 on the pulley J2 side. At this time, the distance between the vertices of the left and right arcs J11 and J12 was set to 100 mm. During measurement, as shown in Figure 8(b), the string J3 attached to the arc J11 was pulled by the measuring device K and pulley J2 to compress the measurement sample 100 until its width was 30 mm. The load at the point when the width of the measurement sample 100 reached 50 mm was measured as the crotch compression load of the measurement sample 100. The measurement conditions were a tensile speed of 50 mm / min and a height of 22 mm from the mounting surface of the measurement sample 100 to the fixing string J4. The measurement results of the compression load in the crotch area of ​​the napkins in the examples and comparative examples are shown in Table 1 below.

[0138] [Table 1] [Explanation of Symbols]

[0139] 1…Navel napkin (absorbent item) 2…Surface sheet 3…Back sheet 3a…Underwear contact surface (non-skin side) 4… Absorbent 4s... Lateral edge of the absorbent 7… Absorbent core 31... Front anti-slip section (anti-slip section) 36…Central area 37...outer area 81…Non-skin side core wrap sheet S1... Non-skin side core adhesive M…Main body M1...front area M2…middle range M3…rear area CL... Vertical center line X... vertical direction (front-back direction) Y... Horizontal direction (left and right direction)

Claims

1. An absorbent article having a longitudinal direction corresponding to the wearer's front-to-back direction and a transverse direction corresponding to the wearer's left-to-right direction, and divided along the longitudinal direction into a front area, a middle area and a rear area, comprising a surface sheet, a back sheet, an absorbent material disposed between the surface sheet and the back sheet, and a plurality of longitudinally extending anti-slip portions disposed on the non-skin side of the back sheet, In a plan view, the region where the absorber exists is, A central region located in the horizontal center including a vertical center line that divides the absorbent in two equal parts horizontally, where the anti-slip portion is not arranged along the entire length in the vertical direction, An outer region located on both lateral sides including the lateral edge of the absorbent, in which the anti-slip portion is not arranged along the entire length in the vertical direction, The slip-preventing portion is positioned between the central region and the outer region, It has, The absorbent body is Absorbent core, A non-skin side core wrap sheet covering the non-skin side of the absorbent core, A non-skin side core adhesive for bonding the absorbent core and the non-skin side core wrap sheet, The non-skin side core adhesive is present over the entire length in the longitudinal direction of at least the intermediate region, In the region of the intermediate area where the absorbent exists in a plan view, in each of the left and right regions separated by the vertical center line, the area ratio of the non-skin side core adhesive is higher in the region where the anti-slip portion exists than in the central region and the outer region. The non-skin side core wrap sheet has a non-skin side core adhesive-free region that overlaps with the central region and the outer region in a plan view, and in which the non-skin side core adhesive that adheres to the absorbent core is absent. The region where the non-skin side core adhesive is absent extends at least along the entire length in the longitudinal direction of the intermediate region. The non-skin side core wrap sheet includes a first core wrap sheet and a second core wrap sheet extending from each of the lateral sides toward the laterally opposing side, The non-skin side core wrap sheet has a sheet overlapping region in the thickness direction in which the first core wrap sheet and the second core wrap sheet located closer to the skin than the first core wrap sheet overlap. The sheet overlapping region includes a non-adherent core wrap region where the first core wrap sheet and the second core wrap sheet are not bonded together. The non-adherent region between the core wraps exists at least along the entire longitudinal length of the intermediate region. The non-skin side core wrap sheet has double-sided non-adhesive regions where the non-adhesive region between the core wraps and the region where the non-skin side core adhesive is absent overlap in a plan view. Absorbent material.

2. The absorbent article according to claim 1, wherein the sheet overlapping region includes a core wrap adhesive region in which the first core wrap sheet and the second core wrap sheet are partially bonded together, and the core wrap adhesive region includes a region in which the portion laterally inward of the lateral edge of the first core wrap sheet and the lateral edge of the second core wrap sheet overlap.

3. The absorbent core has a rigidity change portion that extends laterally, The stiffness change portion is located in the front region when the rear region is divided vertically into two equal parts. The absorbent article according to claim 1 or 2.

4. The absorbent core has a high basis weight portion in which the basis weight of the constituent material constituting the absorbent core is relatively high, and a low basis weight portion in which the basis weight is relatively low, The stiffness change portion is the boundary between the high basis weight portion and the low basis weight portion located longitudinally behind the high basis weight portion. The high-basis-weight portion has a convex shape that is convex in the longitudinal direction backward, extending diagonally backward from each of the lateral edges of the absorbent core toward the longitudinal center line. In a plan view, the top of the convex shape of the high basis weight portion is located in the double-sided non-adhesive region. The absorbent article according to claim 3.

5. The boundary is formed by the difference in thickness between the high-basis-weight portion and the low-basis-weight portion, and the boundary is located on the non-skin side of the absorbent core. The surface sheet and the absorbent further include recesses that are recessed toward the back sheet side, The recess reaches the non-skin side core wrap sheet and is positioned to straddle the boundary in the vertical direction in the region that overlaps with the anti-slip portion in a plan view. The absorbent article according to claim 4.

6. The absorbent body is A skin-side core wrap sheet covers the skin-side surface of the absorbent core, A skin-side core adhesive for bonding the absorbent core and the skin-side core wrap sheet, The further comprising, the skin-side core adhesive is present over the entire longitudinal length of at least the intermediate region, In the aforementioned intermediate region, the lateral edges of the coating areas of the skin-side core adhesive and the non-skin-side core adhesive overlap with the outer region in a plan view, and the lateral edges of the coating area of ​​the skin-side core adhesive are positioned laterally inward than the lateral edges of the coating area of ​​the non-skin-side core adhesive. The absorbent article according to claim 1 or 2.

7. The absorbent core has a rigidity change portion that extends laterally, It has an intermittent region located behind the rigidity change portion, in which the slip-preventing portion is not arranged over the entire lateral direction, The non-skin side core adhesive overlaps with the intermittent region in a plan view in at least part of it. The absorbent article according to claim 1 or 2.

8. Within the region from the rearmost end of the anti-slip portion to the rear end of the absorbent article, there is further a rear compression portion extending laterally in which the surface sheet and the absorbent material are integrated, The rear compression portion reaches the non-skin side core wrap sheet and partially overlaps with the non-skin side core adhesive in a plan view. The absorbent article according to claim 5.

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