Absorbent article

Abstract

This absorbent article comprises a front surface sheet, a back surface sheet, an absorbent body, and a displacement prevention part. A region in which the absorbent body is present in plan view in the absorbent article has a central region, outer regions, and the displacement prevention part disposed between the central region and the outer regions. The central region is positioned at the lateral center of the absorbent body including a longitudinal center line. The outer regions are positioned on both lateral sides of the absorbent body. The absorbent body is provided with: an absorbent core; a non-skin-side core wrap sheet that covers the non-skin-side surface of the absorbent core; and a non-skin-side core adhesive that adheres the absorbent core to the non-skin-side core wrap sheet. The non-skin-side core adhesive is present over the entire longitudinal length of a longitudinal intermediate region of the absorbent article. In each of the left and right regions divided by the longitudinal center line in the region of the intermediate region where the absorbent body is present, the area ratio of the non-skin-side core adhesive is greater in the region where the displacement prevention part is present than in the central region and the outer regions.

Description

Absorbent article

[0001] The present invention relates to an absorbent article such as a sanitary napkin.

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

[0003] Patent Document 1 discloses an absorbent article in which a plurality of linear absorbent adhesives along the longitudinal direction are provided between an absorbent core and a core wrap sheet arranged on the non-skin side of the absorbent core to prevent the generation of gaps, for the purpose of suppressing twisting of the entire absorbent body. In this absorbent article, a bending guide portion is provided between the misalignment prevention adhesive layers at the center in the width direction in order to improve the fit to the excretory part. The bending guide portion is formed as a linear compressed portion having a central recess that is recessed toward the skin side, and guides the absorbent article to bend toward the skin side.

[0004] Japanese Unexamined Patent Publication No. 2017-46786

[0005] 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 orthogonal to each other. The absorbent article is divided into a front region, a middle region, and a rear region 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 longitudinally extending anti-slip portions disposed on the non-skin side of the back sheet. In a plan view of the absorbent article, the region where the absorbent material exists has a central region, an outer region, and the anti-slip portions. The central region is located in the transverse center including a longitudinal center line that bisects the absorbent material transversely. The anti-slip portions are not arranged along the entire length of the longitudinal direction in the central region. The outer region is located on both transverse sides including the transverse side edges of the absorbent material. The anti-slip portions are not arranged along the entire length of the longitudinal direction in the outer region. The anti-slip portions are disposed between the central region and the outer region. The absorbent body comprises a non-skin side core wrap sheet and a non-skin side core adhesive. The non-skin side core wrap sheet covers the non-skin side of the absorbent core. The non-skin side core adhesive adheres the absorbent core to the non-skin side core wrap sheet. The non-skin side core adhesive is present over at least the entire length in the longitudinal direction of the intermediate region. In the region of the intermediate region where the absorbent body 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 longitudinal center line.

[0006] This is a plan view showing an absorbent article according to one embodiment of the present invention as viewed from the skin side. This is a plan view of the absorbent article as viewed from the non-skin side. This is a schematic cross-sectional view of the intermediate region of the absorbent article cut along the line III-III in Figure 1. This is a schematic cross-sectional view of the intermediate region of the absorbent article cut along the line VI-VI in Figure 1. This is a partially enlarged view of Figure 4, which is a schematic cross-sectional view for explaining the positional relationship between the absorbent core, the non-skin side core wrap sheet, and the anti-slip portion. This is a plan view of the absorbent core constituting a part of the absorbent article, which is a diagram for explaining the positional relationship between the components of the absorbent core, the non-skin side core adhesive, and the anti-slip portion. This is a schematic partially enlarged cross-sectional view of the intermediate region of an absorbent article as a modified example. This is an explanatory diagram of a method for measuring the compression load in the groin area, where (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 vertical direction of the measurement sample indicated by reference numeral 100). Detailed description of the invention

[0007] In the absorbent article described in Reference 1, multiple absorbent adhesives extending linearly in the longitudinal direction (vertical direction) are evenly distributed in the width direction. Therefore, when an external force is applied to the absorbent article in the width direction (lateral direction) during wear, the force cannot be effectively transmitted to the bending guide located in the center in the lateral direction, making it difficult to obtain a sufficient fit. In addition, in the absorbent article described in Reference 1, multiple linear absorbent adhesives are provided throughout the entire width direction of the absorbent core, resulting in high rigidity on both lateral sides of the absorbent, making it difficult to get a good fit.

[0008] 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.

[0009] Embodiments of the present invention will be described below with reference to the drawings. Each drawing shows, as appropriate, mutually orthogonal coordinate axes: the X-axis, Y-axis, and Z-axis. In the following description, previously described components will be denoted by the same reference numerals, and their descriptions may be omitted.

[0010] <Overall Structure of Absorbent Article> An absorbent article 1 according to one embodiment of the present invention is configured as a sanitary napkin and will be hereinafter referred to as napkin 1. Napkin 1 has a vertical direction X corresponding to the wearer's front-to-back direction and a horizontal direction Y corresponding to the wearer's left-to-right direction and perpendicular to the vertical direction X. Furthermore, napkin 1 has a thickness direction Z perpendicular to both the vertical direction X and the horizontal direction Y. The vertical direction X coincides with the longitudinal direction of napkin 1, and the horizontal 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 the top or skin side, and the side closer to underwear may be expressed as the bottom or non-skin side. In this specification, "plan view" means a plan view as seen from the thickness direction Z. In this specification, unless otherwise specified, "inside of horizontal direction Y" means approaching the horizontal direction Y toward the vertical center line CL that bisects the horizontal direction Y of napkin 1, and "outside of horizontal direction Y" means moving away from the vertical center line CL in the horizontal direction Y. The vertical center line CL coincides with the vertical center line that bisects the horizontal direction Y of the absorber, as described later. In this specification, "width" and "horizontal width" refer to the length in the horizontal direction Y.

[0011] As shown in Figure 1, the absorbent article 1 comprises a main body M, a pair of wings W, and a pair of hip guards H.

[0012] The main body M extends in a band shape along the vertical direction X and is fixed to the inner surface of the wearer's underwear when worn. The main body M is divided along the vertical direction X into a front area M1, a middle area M2, and a rear area M3. The middle area M2 includes an excretory area facing the wearer's excretory area when worn. This excretory area facing the wearer's excretory area is located in the center of the middle area M2 in the horizontal direction Y. The excretory area is the vaginal opening when the absorbent item is a sanitary napkin 1. In the case of a sanitary napkin 1, the middle area M2 is the area that overlaps with the area where the wings W are provided in the vertical direction X. The middle area M2 is the area where an external force is applied from both of the wearer's legs inward in the horizontal direction Y when worn. The front area M1 is the area located in front of the middle area M2 (on the wearer's abdominal side) and faces the front of the wearer's excretory area when worn. The posterior region M3 is located behind the intermediate region M2 (on the wearer's back) and faces the wearer's excretory area when worn. In napkin 1, the posterior region M3 overlaps with the region where the hip guard H is provided in the longitudinal direction X. "When worn" here means when the normal, proper wearing position (the expected wearing position of napkin 1) is maintained, and does not include cases where napkin 1 is shifted from that wearing position.

[0013] The main body M extends along the vertical direction X and is positioned on the inner surface of the wearer's underwear. The main body M has the function of absorbing liquid substances such as the wearer's menstrual blood (hereinafter also referred to as "liquid").

[0014] A pair of wings W extend laterally outward in the lateral direction Y from the middle region M2 of the main body M. The wings W extend laterally outward from the underwear at the wearer's crotch, are folded inward, and are fixed to the outer surface of the underwear. This prevents the middle region M2 of the main body M from shifting away from the wearer's crotch.

[0015] A pair of hip guards H extend laterally Y outward from the rear area M3 of the main body M, partially enveloping the buttocks inside the wearer's underwear. The hip guards H are positioned behind the wings W.

[0016] As shown in Figure 1, the napkin 1 has a constricted portion between the wing W and the hip guard H, where the left and right side edges along the vertical direction X are constricted inward in the horizontal direction Y. In the napkin 1 according to this embodiment, the front end of the hip guard H coincides with the rear end of the wing W.

[0017] As shown in Figures 1 to 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, the absorbent core 4, and the 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.

[0018] 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, for example, adhesive E. 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, for example, its periphery, by a third adhesive 53, heat sealing, etc. In addition, the third adhesive 53 is applied to almost the entire non-skin side of the absorbent body 4, bonding the absorbent body 4 to the back sheet 3.

[0019] The surface sheet 2 is made of a highly permeable sheet material so as to allow liquids such as menstrual blood to be easily absorbed into the interior from the top. 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 absorbed into the interior 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.

[0020] On the non-skin side of the back sheet 3, anti-slip portions 31 to 34 are provided to secure the main body M, wing W, and hip guard H to the underwear. Hereinafter, the surface of the napkin 1 on which the anti-slip portions 31 to 34 are provided 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 to 34 will be described later.

[0021] 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.

[0022] 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.

[0023] 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 into two equal parts in the horizontal direction Y by the vertical center line CL, the left side is called the first intermediate region absorber-existing region 41, and the right side is called the second intermediate region absorber-existing region 42.

[0024] The absorbent body 4 comprises an absorbent core 7 and a core wrap sheet 8.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] <Detailed Configuration of Absorbent Article> [Non-Skin Core Wrap Sheet] As shown in Figure 5, the non-skin core wrap sheet 81 has a left side portion 81sL, which is one side in the lateral direction Y, specifically the left side, and a right side portion 81sR, which is the other side in the lateral direction Y, specifically the right side. The left side portion 81sL and the right side portion 81sR face each other in the lateral direction Y. The non-skin 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 portion 81sL toward the right side portion 81sR to near the center of the central portion 45 of the absorbent body in the lateral direction Y. The second core wrap sheet 812 extends from the right side portion 81sR toward the left side portion 81sL to the central portion 45 of the absorbent body.

[0029] 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.

[0030] The sheet overlapping region B exists over at least the entire length in the vertical direction X of the intermediate region M2 (the entire length in the vertical direction X), and in napkin 1, it exists over the entire length in the vertical direction X of the absorbent core 7. In napkin 1, in a plan view, the sheet overlapping region B is located near the center in the horizontal direction Y of napkin 1, including the vertical center line CL, and is located in the central part 45 of the absorbent material.

[0031] [Anti-slip portion] As shown in Figure 2, the napkin 1 includes a pair of front 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 of which are 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.

[0032] (Wing Anti-Slip 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.

[0033] (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.

[0034] (Front and Rear Anti-Slip Sections) The pair of front anti-slip sections 31 and the pair of rear anti-slip sections 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 sections 31 and the rear anti-slip sections 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 sections are present in the area where the absorbent material 4 is not present. The front anti-slip section 31 extends continuously in the vertical direction X across a part of the front area M1, the middle area M2, and a part of the rear area M3. One front anti-slip section 31 is placed on each of the left and right sides of the front anti-slip section 31 with the vertical center line CL in between, and is provided as a pair. The rear anti-slip section 32 extends continuously in the vertical direction X towards the rear of the rear area M3. One rear anti-slip section 32 is placed on each of the left and right sides of the rear anti-slip section 32 with the vertical center line CL in between, and is provided as a pair.

[0035] As shown in Figure 2, on the underwear contact surface 3a, the pair of rear 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 rear 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 rear anti-slip portions 32 are separated in the vertical direction X. Both the front anti-slip portions 31 and the rear 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 that corresponds to the vicinity of the wearer's anus in the vertical direction X.

[0036] 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 such a 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.

[0037] As shown in Figures 2 to 4, in the region of the intermediate area M2 of the napkin 1 where the absorbent material 4 is located in a plan view, a central region 36 is located between the pair of forward anti-slip portions 31, extending over the entire length of the intermediate area M2 in the vertical direction X. Furthermore, outer regions 37 are located on both the left and right sides of the pair of forward anti-slip portions 31, extending over the entire length of the intermediate area M2 in the vertical direction X. In other words, the region of the intermediate area M2 of the napkin 1 where the absorbent material 4 is located in a plan view comprises a central region 36, an outer region 37, and forward anti-slip portions 31, with the forward anti-slip portions 31 positioned between the central region 36 and the outer region 37. Moreover, in the napkin 1 of this embodiment, the central region 36 and the outer region 37, where no anti-slip portions are continuously arranged in the vertical direction X, extend not only over the intermediate area M2 but also over the entire length of the region where the absorbent material 4 is located in a plan view in the vertical direction X.

[0038] 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 regions 37 are located in the lateral part 46 of the absorbent material. Of the pair of outer regions 37, the outer region on the left is called the first outer region 371, and the outer region 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 regions 37.

[0039] As shown in Figure 5, the central region 36 is divided by the vertical center line CL, and includes 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.

[0040] [Non-skin side 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.

[0041] 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 longitudinal 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 longitudinal direction X" is not limited to the non-skin side core adhesive S1 extending in a linear manner parallel to the longitudinal direction X, but also includes the non-skin side core adhesive S1 extending diagonally with respect to the longitudinal direction X, or locally curved or meandering. Furthermore, the non-skin side core adhesive S1 is not limited to being applied continuously in the longitudinal direction X, but may also be applied intermittently in a spiral manner, for example, where there are breaks on an imaginary line extending in the longitudinal direction X within the application area A10 of one non-skin side core adhesive S1, but the adhesive is applied continuously. Specific coating patterns for the non-skin-side core adhesive S1 include, as an example of continuous coating, linear, spiral, dot, and dashed line patterns where the adhesive is intermittently arranged along a virtual line extending in the vertical direction X. In the example shown in Figure 2, the non-skin-side core adhesive S1 is coated 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 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 pattern, and 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.

[0042] 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 on each side of the non-skin side core adhesive coating area A10, separated by a vertical center line CL, forming a pair. Similarly, the area obtained by surrounding the outer edge of the coating area of ​​the skin side core adhesive S2 in a roughly rectangular shape is called the skin side core adhesive coating area A2.

[0043] As shown in FIGS. 3 and 4, in the intermediate region M2 of the napkin 1, each of the pair of non-skin-side core adhesive application regions A10 has a belt shape extending in the longitudinal direction X. The pair of non-skin-side core adhesive application regions A10 are arranged spaced apart from each other in the transverse direction Y. The region obtained by surrounding the two non-skin-side core adhesive application regions A10 is referred to as the entire non-skin-side core adhesive application region A1. As shown in the plan view of FIG. 2, in the region where the absorbent body 4 of the napkin 1 is present, the non-skin-side core adhesive S1 does not exist on both lateral sides of the entire non-skin-side core adhesive application region A1, and the non-skin-side core adhesive S1 does not exist in the lateral center and on both lateral sides.

[0044] As shown in FIGS. 3 and 4, the entire non-skin-side core adhesive application region A1 has a pair of side edges S1s opposing each other in the transverse direction Y. The skin-side core adhesive application region A2 has a pair of side edges S2s opposing each other in the transverse direction Y.

[0045] As shown in FIG. 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 an inter-core-wrap non-adhesive region 401 where no adhesive is disposed on the skin-side surface thereof. The inter-core-wrap non-adhesive region 401 is an adhesive absent region where no adhesive is disposed. In a plan view, the inter-core-wrap non-adhesive region 401 is located in the sheet overlapping region B, and at least a part thereof is located in the central region 36. The inter-core-wrap non-adhesive region 401 is a region where no adhesive is disposed between the first core wrap sheet 811 and the second core wrap sheet 812, and the two sheets are not adhered to each other by an adhesive. In a plan view, the inter-core-wrap non-adhesive region 401 is positioned so as to include the longitudinal center line CL.

[0046] Further, like the napkin 1 of the present embodiment shown in FIG. 5, the first core wrap sheet 811 may have a first lateral non-skin-side core adhesive absent region (non-skin-side core adhesive absent region) 402 where the non-skin-side core adhesive S1 is not disposed on the skin-side surface thereof. In a plan view, the first lateral non-skin-side core adhesive absent 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.

[0047] In FIG. 5, the non-adhesion region between core wraps 401 is represented by a dashed-dotted rectangular box, and the first lateral non-skin-side core adhesive absence region 402 is represented by a broken-line rectangular box.

[0048] Also, in the sanitary napkin 1, as shown in FIG. 5, the non-skin-side core wrap sheet 81 has, in the sheet overlapping region B, besides the inter-core-wrap non-adhesion region 401 where the first core wrap sheet 811 and the second core wrap sheet 812 are not bonded to each other, an inter-core-wrap adhesion region D where the first core wrap sheet 811 and the second core wrap sheet 812 are bonded to each other by the non-skin-side core wrap sheet adhesive Sd.

[0049] As shown in FIG. 5, the second core wrap sheet 812 is positioned 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 absence region (non-skin-side core adhesive absence region) 403 where the non-skin-side core adhesive S1 is not disposed on the skin-side surface thereof. In plan view, the central non-skin-side core adhesive absence region 403 is located in the sheet overlapping region B, and at least a portion thereof is located in the central region 36. In plan view, the central non-skin-side core adhesive absence region 403 is positioned so as to include the vertical center line CL.

[0050] Also, like the sanitary napkin 1 of the present embodiment shown in FIG. 5, the second core wrap sheet 812 may have a second lateral non-skin-side core adhesive absence region 404 where the non-skin-side core adhesive S1 is not disposed on the skin-side surface thereof. In plan view, the second lateral non-skin-side core adhesive absence 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.

[0051] In FIG. 5, the central non-skin-side core adhesive absence region 403 and the second lateral non-skin-side core adhesive absence region 404 are represented by broken-line rectangular boxes.

[0052] 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.

[0053] As shown in Figure 5, in the absorbent body 4, the non-skin side core wrap sheet 81 has a double-sided non-adhesive region C, which is a region where the non-adhesive region 401 between 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-adhesive region 401 between core wraps and the adhesive region D between core wraps are located in the sheet overlapping 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 component. 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.

[0054] 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.

[0055] 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).

[0056] Furthermore, the non-skin side core adhesive S1 may be arranged such that the width of the non-skin side core adhesive coating area A10 is equal to the width of the forward slip prevention portion 31, and the side edges of the non-skin side core adhesive coating area A10 coincide with the side edges of the forward slip prevention portion 31 in the lateral direction Y when viewed from above. 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 the 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 when viewed from above.

[0057] 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. By doing so, 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 prone to deformation, making it easier to fit to the groin area in the outer region.

[0058] 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 deviations 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 width of the central region 36 may be wider or narrower than the sheet overlapping region B.

[0059] [Relative relationship of area ratio of non-skin side core adhesive S1 in intermediate region M2] In napkin 1, in the first intermediate region absorbent area 41, the area ratio of non-skin side core adhesive S1 is higher in the region where the forward 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 region absorbent area 42, the area ratio of non-skin side core adhesive S1 is higher in the region where the forward 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 "relative relationship of area ratio of non-skin side core adhesive S1" (hereinafter referred to as configuration A). This achieves both resistance to twisting and fit of the absorbent 4 in the intermediate region M2 in the vertical direction X.

[0060] Here, when a sanitary napkin is worn, the napkin 1 is fixed to the wearer's underwear by the anti-slip portion, including the front 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 front 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 fixed via the front 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. In particular, when the napkin 1 is worn for a long time, the absorbent body 4 tends to wrinkle more easily, which tends to cause leakage of excretory fluid. However, in the napkin 1 of this embodiment, even when worn for a long time, the non-skin side core adhesive S1 is positioned so as to overlap with the forward slip-preventing portion 31 in a plan view, thereby effectively suppressing the occurrence of gaps between the absorbent core 7 and the non-skin side core wrap sheet 81, making it less likely for the absorbent body 4 to wrinkle and less likely for leakage of excretory fluid.

[0061] 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 gaps between the absorbent core 7 and the non-skin side core wrap sheet 81, in the configuration A described above. In the napkin 1, having configuration A, in the intermediate region M2, the area of ​​the absorbent body 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 directed inward in the lateral direction Y is applied to the absorbent body 4 in the intermediate region M2, the absorbent body 4 is less likely to follow the deformation of the underwear, and twisting in the lateral direction Y is easily suppressed. Combined with the synergistic effect of the non-skin side core adhesive S1 suppressing the occurrence of gaps between the absorbent core 7 and the non-skin side core wrap sheet 81, the shape retention effect of the absorbent core 7 is improved, the resistance of the absorbent body 4 to twisting is improved, and good liquid absorption can be maintained. On the other hand, in the intermediate region M2, the region of the absorbent 4 that overlaps with the central region 36 and the outer region 37 in a plan view is configured A 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 the napkin 1, configuration A achieves both resistance to twisting of the absorbent 4 in the intermediate region M2 and a good fit.

[0062] [Specific Examples for Realizing Configuration A] In order to realize Configuration A, for example, as shown in Figure 5, etc., the napkin 1 of this embodiment may have a non-skin side core adhesive-free region in the area that overlaps with the central region 36 and the outer region 37 in a plan view of the absorbent body 4, where there is no non-skin side core adhesive that adheres the non-skin side core wrap sheet 81 and the absorbent core 7, and this region may exist at least along the entire length of the vertical direction X of the intermediate region M2. Details will be described later.

[0063] As another example, in order to realize configuration A, in the region where the absorber 4 of the intermediate region M2 is located, in a plan view, the non-skin side core adhesive may be applied to only 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 is located, in a plan view, in a region where the central region 36 and the outer region 37 are located, in one region (central region 36 or outer region 37), the non-skin side core adhesive may be applied to only a part of the region in the vertical direction X, leaving the majority uncoated, while in the other region, a region without non-skin side core adhesive may be provided along the entire length of the vertical direction X.

[0064] As another example, in order to realize configuration A, a low-basis-weight non-skin adhesive coating area may be provided in the region where the absorber 4 in the intermediate region M2 exists, in a plan view, where the non-skin adhesive is applied to the non-skin adhesive coating area A10 in Figure 5 (in other words, the non-skin adhesive applied to the region that substantially overlaps with the forward slip-preventing portion 31 in a plan view), thereby providing a low-basis-weight non-skin core adhesive coating area. Alternatively, in order to realize configuration A, in the region where the absorber 4 in the intermediate region M2 exists, in a plan view, where the central region 36 and the outer region 37 overlap, a low-basis-weight non-skin core adhesive coating area may be provided in one region (central region 36 or outer region 37), and a non-skin core adhesive-free region may be provided in the other region, where the non-skin 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" described above will be smaller than the area ratio of the non-skin core adhesive in the non-skin core adhesive coating area A10.

[0065] Furthermore, the method for realizing configuration A is not limited to the method described herein.

[0066] (Detailed description of the embodiment that realizes configuration A by providing non-skin side core adhesive-free regions in the central region and outer region) In a preferred embodiment that realizes configuration A, as shown in Figure 5, in the region of the absorbent body 4 that overlaps with the central region 36 and the outer region 37 in a plan view, there are non-skin side core adhesive-free regions (central non-skin side core adhesive-free region 403, first lateral non-skin side core adhesive-free region) where there is no non-skin side core adhesive that adheres the non-skin side core wrap sheet 81 and the absorbent core 7, and these regions exist over at least the entire length of the intermediate region M2 in the longitudinal direction X.

[0067] 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.

[0068] 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 arranged such that it overlaps with the forward slip-preventing 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, in the first intermediate absorbent region 41, 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 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 absorbent region 42, thereby realizing configuration A.

[0069] As shown in Figure 2, in the middle region M2 of the 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 in the lateral direction Y of the strip-shaped non-skin side core adhesive coating area A10 extends slightly outward than the outer edge in the lateral direction Y of the forward slip prevention portion 31. 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.

[0070] 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 during wear, 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.

[0071] 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 due to the relaxation of internal forces, the ratio of the length in the lateral direction Y of the portion of the central non-skin side core adhesive-free region 403 that overlaps with the central region 36 in a plan view to the length in the lateral direction Y of the portion of the central non-skin side core adhesive-free region 403 that 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.

[0072] 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 extends over 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.

[0073] This configuration promotes the effect of suppressing twisting of the absorber 4 by mitigating internal forces during convex deformation in the central region 36. In other words, in the absorber 4, the double-sided non-adhesive region C is a region in which the non-skin side core adhesive S1 and the non-skin side core wrap sheet adhesive Sd do not exist when viewed in plan. In the double-sided non-adhesive region C, both sides of the second core wrap sheet 812, which is located above the first core wrap sheet 811 in the sheet overlap region B (on the absorbent core side), 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 absorber 4 during wear, the first and second core wrap sheets 811, 812 and the absorber 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 absorber 4, especially the absorbent core 7, by mitigating the internal forces. Furthermore, even after the convex deformation of the central region 36 in 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 sustained more reliably, thus maintaining good fit in the intermediate region M2.

[0074] In napkin 1, the first and second core wrap sheets 811 and 812 are bonded together by the non-skin side core wrap sheet adhesive Sd in the sheet overlapping region B, 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 are located in the sheet overlap region B. The phrase "laterally inward from the lateral edge 811a of the first core wrap sheet 811" refers to the area laterally inward of the first core wrap sheet 811 from the perspective of the first core wrap sheet 811, beyond the lateral edge 811a.

[0075] 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.

[0076] 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-adhesive 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 a specific numerical example, the width of the core-wrap adhesive region D is about 2.5 mm to 5.5 mm, and the width of the core-wrap non-adhesive region 401 is about 7.5 mm to 10 mm. However, the values ​​are not limited to those listed here.

[0077] 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 in the center of 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.

[0078] 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 the region where the forward slip prevention portion 31 and the non-skin side core adhesive S1 overlap in a plan view (overlapping region).

[0079] When an external force is applied to the intermediate region M2 in the wearer's crotch area in the lateral direction Y, the presence of a pair of high-rigidity regions 20 extending in the vertical direction X 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 extending in the vertical direction X, which is preferentially prone to deformation due to its low rigidity, causing the central region 36 to deform convexly toward the wearer's excretory area, making it easier to fit the shape of the wearer's crotch. Moreover, in the region where the absorbent material 4 exists in a plan view of the intermediate region M2, a pair of outer regions 37 form a pair of second low-rigidity regions 22 extending in the vertical direction X, which is preferentially prone to deformation due to its low rigidity, making it easier to fit the wearer's inguinal region. Furthermore, in the intermediate region M2, the region lateral to the outside Y of the absorber 4 has lower rigidity than the region where the absorber 4 is present because the absorber 4 is absent. The regions located on either side of the pair of second low-rigidity regions 22 (regions without absorbers) also become low-rigidity regions, and these low-rigidity regions, along with the pair of second low-rigidity regions 22, are designed to fit more easily to the groin area.

[0080] Thus, napkin 1 achieves both improved resistance to shifting of the absorbent material 4 during wear and a good fit. Furthermore, the improved resistance to shifting and the better fit make it possible to effectively suppress leakage of excretory fluids even when napkin 1 is worn for extended periods.

[0081] <Further detailed configuration of the absorbent article> [Absorbent core] From the viewpoint of further enhancing resistance to twisting and improving the effect of 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 the rigidity change portion is located in the front region M31 (see Figure 1) when the rear region M3 of the napkin 1 is divided into two equal parts in the vertical direction X. The rigidity change portion is the part in which the rigidity of the absorbent core 7 changes when viewed along the vertical direction X.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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 fibrous 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 the like is placed within the high-basis-weight section, the entire area is referred to as the high-basis-weight section, but the basis weight of the portion other than 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 weights, 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.

[0087] 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 rectangular 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.

[0088] 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. This increases the amount of liquid absorbed in the intermediate area M2 (area opposite the excretion area) where 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 area M2. On the other hand, because the high-rigidity front high-basis-weight portion 71 is arranged over the entire lateral Y area, the rigidity of the absorbent side portion 46 of the absorbent body 4 in the intermediate area M2 tends to increase. However, in the napkin 1 of this embodiment, by using the above configuration (a), the rigidity of the absorbent side portion 46 does not become excessively high, and the napkin 1 can be gently fitted to the groin area.

[0089] The posterior high-weight portion 72 is located at the center of the lateral Y direction of the posterior region M3. The posterior high-weight portion 72 is located further posterior in the vertical X direction than the anterior high-weight portion 71, and is spaced apart from the anterior high-weight portion 71. When worn, the anterior high-weight portion 71 is located opposite the excretory area (vaginal opening), and the posterior high-weight portion 72 is located opposite the gluteal cleft. The presence of a spaced-out region 75 consisting of a low-weight portion 70 makes it easier for the napkin 1 to deform to conform to the shape of the body, wrapping around the buttocks in the vertical direction. Furthermore, in the napkin 1, the posterior high-weight portion 72 is located at the center of the lateral Y direction, and the low-weight portions 70 with low rigidity and the hip guard H without absorbent material 4 are located on both sides thereof, making it easier for the napkin 1 to deform to wrap around the left and right curves of the buttocks from the left and right directions.

[0090] 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.

[0091] 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 area of ​​the absorbent core 7 and is located across a part of the intermediate area M2 and a part of the rear area M3. In the rear area M3, the rigidity change section 73 is located in the area M31 in front of the horizontal line L1, which is drawn when a horizontal line L1 is drawn to bisect the rear area M3 of the napkin 1 in the vertical direction X, and is not located behind the horizontal line L1.

[0092] 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.

[0093] 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 overlap almost completely. 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 where 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 come into 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.

[0094] 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 material 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 the highly rigid rear high basis weight section 72 relative to the buttock cleft, the rear region M3 of the main body M is less prone to unintended deformation, the liquid absorption capacity of liquids flowing toward the rear of the napkin 1 can be maintained well, and the amount of liquids that can be absorbed toward the rear of the napkin 1 can be increased. 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 the buttock cleft, effectively suppressing leakage.

[0095] 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.

[0096] In addition, in the napkin 1 of this embodiment, as shown in Figures 2 and 5, the rigidity 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 rigidity 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 rigidity change portion 73 is denoted by reference numeral 73a. In the napkin 1, in a plan view, the top of the convex shape 73a of the rigidity change portion 73 is located in the non-adhesive region C on both sides.

[0097] This configuration allows 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) to 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, which 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.

[0098] [Round Compression Section, First Lateral Compression 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 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. Note that "linear groove" includes both a form in which the compression section extends continuously to form a line, and a form in which a plurality of compression sections are intermittently arranged and can be considered as a single linear groove as a whole. In linear grooves, "extending in the vertical direction X" or "extending in the horizontal direction Y" means that the entire groove extends in the vertical direction X or horizontal direction Y, and includes cases where a part of it 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.

[0099] 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 region M1 through the intermediate region M2 to the rear region 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.

[0100] 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 vertical direction X of each of the pair of vertical compression sections 61.

[0101] As shown in Figure 4, in the napkin 1, the rigidity change portion 73 (the 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 the 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.

[0102] 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.

[0103] 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.

[0104] 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.

[0105] [Rear Compression Section] As shown in Figure 1, the surface sheet 2 may have a rear compression section 13 in the rear area 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. The rear compression section 13 overlaps with the non-skin side core adhesive S1 in a plan view. More specifically, the rear compression section 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, while the central part in the lateral direction Y does not overlap with the non-skin side core adhesive S1 in a plan view.

[0106] 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, so that the non-skin side core wrap sheet 81 and the absorbent core 7 can be firmly bonded in the overlapping portion. This makes it less likely for gaps to form between the non-skin side core wrap sheet 81 and the absorbent core 7, and further suppresses twisting of the absorbent body 4.

[0107] 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.

[0108] [Skin-side core adhesive] 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, as shown in Figures 3 and 4 of the napkin 1 of this embodiment.

[0109] 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 so as to form a coating area that is continuous in the transverse direction Y. Both side edges S2s of the skin-side core adhesive S2 in the transverse direction Y overlap with the outer region 37 in a plan view.

[0110] In napkin 1, the non-skin side core adhesive S1 is present over the entire length of the longitudinal direction X 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 coating regions A10 that are spaced apart in the transverse direction Y. In other words, the non-skin side core adhesive S1 is applied so as to be an intermittent coating region in the transverse direction Y. As shown in Figures 3 and 4, both side edges S1s in the transverse direction Y of the entire non-skin side core adhesive coating region A1 overlap with the outer region 37 in a plan view.

[0111] 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 than the pair of side edges S1s of the non-skin-side core adhesive S1. This configuration reduces discomfort when worn in the groin area while maintaining a good fit. Specifically, by positioning the pair of side edges S2s of the skin-side core adhesive S2, which is located closer to the wearer's skin than the non-skin-side core adhesive S1, laterally inward in the Y direction than the pair of side edges S1s of the non-skin-side core adhesive S1, the rigidity of the skin-side (upper) portion of the absorbent side portion 46 is reduced, thereby reducing discomfort when worn in the groin area. At the same time, the rigidity of the non-skin-side (lower) portion of the absorbent side portion 46 is increased, which firmly fixes the napkin 1 to the underwear, making the napkin less likely to bunch up and maintaining a good fit.

[0112] [Positional relationship between the non-skin side core adhesive and the intermittent region] As shown in Figure 2, 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.

[0113] The intermittent region 35 is located in the rear region M3, where there is no anti-slip portion, and is a region that does not adhere to 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 rear 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, making it easier to suppress twisting in the intermediate region M2. In addition, by providing 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 rear region M3, it becomes easier to fit the rear 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 twisting 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. As a result, even if external force is applied to the napkin 1 due to the wearer's vigorous movements, undesirable deformations such as twisting are less likely to occur in the intermittent region 35 of the main body M, making it easier to maintain a good fit.

[0114] 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.

[0115] [Examples of dimensions for each component] Below are examples of dimensions for each component, but they are not limited to these. The dimensions of each component can be appropriately set by the length of the napkin 1 (length in the vertical direction X), the length and width of the absorbent 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 the absorbent 4 is preferably 300 mm to 330 mm, and the width of the absorbent 4 is preferably 65 mm to 75 mm. In napkin 1, the length of the absorbent 4 is 316 mm and the width is 73 mm.

[0116] (Example dimensions for the anti-slip portion) 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 a pair of front anti-slip portions 31 in the horizontal direction Y is preferably 5 mm to 20 mm, and in napkin 1 it is 10 mm. The position of the rear end 31a of the front anti-slip portion 31 that defines the front position of the intermittent region 35 is preferably set 30 mm to 125 mm behind the excretion point. The excretion point is the center position of the vertical 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, and in napkin 1 it is 40 mm, from the viewpoint of ensuring good liquid absorption and positioning the intermittent region 35 near the anus.

[0117] 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 the 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.

[0118] 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.

[0119] (Examples of dimensions of non-skin side core adhesive S1 and skin side core adhesive S2) The vertical width of the non-skin side core adhesive coating area A10, which is the area coated with the non-skin side core adhesive S1, is preferably 120 mm to 450 mm, and the horizontal width is preferably 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 horizontal width of the entire non-skin side core adhesive coating area A1 (corresponding to the distance between the two side edges S1s of the pair in the horizontal Y direction) is preferably 55 mm to 70 mm, and in napkin 1 it is 67 ± 3 mm. In the absorbent body 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 body 4 in a plan view is preferably 1 mm to 5 mm, and in the case of the napkin 1, it is 2.5 ± 0.5 mm.

[0120] 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 pair of lateral Y-edges S2s) 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.

[0121] (Example dimensions of sheet overlapping area) From the viewpoint of making the core wrap sheet less likely to curl up 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 area C is preferably 2 mm to 15 mm, and is 5 mm for napkin 1.

[0122] (Area ratio of non-skin side core adhesive) 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 is present in a plan view.

[0123] 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 first central region 361 (second central region 362) < first outer region 371 (second outer region 372) < region where the anterior slip-prevention portion 31 exists, because when a strong force is applied from the thigh inward in the lateral direction Y, 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 as a buffer region for the aforementioned external force, thus contributing to the resistance of the entire absorbent material from twisting.

[0124] 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 anterior 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 absorbent and fit in the intermediate region M2 in the vertical direction X. Also, 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 the lower limit should preferably be 0.1 or greater, in order to achieve a high level of both resistance to twisting of the absorbent and fit in the intermediate region in the vertical direction even when a strong force is applied from the thigh toward the inside in the lateral direction Y.

[0125] From the viewpoint of ensuring that the central region 36 of the absorbent body 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 is applied overlapping 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 adheres 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%.

[0126] When worn, in order to ensure that the absorbent material 4 fits well to the groin area and effectively suppress wrinkles, 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%.

[0127] From the viewpoint of effectively suppressing the twisting of the absorber 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-preventing portion 31 exists is determined for each forward slip-preventing portion 31 located in the intermediate region M2 by dividing the area of ​​the coating area of ​​the non-skin side core adhesive S1 that overlaps the forward slip-preventing portion 31 in a plan view by the area of ​​the forward slip-preventing portion 31, and then multiplying by 100.

[0128] <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.

[0129] 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.

[0130] 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.

[0131] <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.

[0132] As the napkin of the example, a napkin 1 having the configuration (i) described in the above embodiment was prepared. As the napkin of the comparative example, a napkin without configuration (i) was prepared by changing the coating pattern of the non-skin side core adhesive S1 placed between the absorbent core and the non-skin side core wrap sheet from that of napkin 1. The napkin of the comparative example 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 napkin of the comparative example, the non-skin side core adhesive S1 was coated in a stripe pattern at equal intervals over the entire area between the absorbent core and the non-skin side core wrap sheet. In other words, in the napkin of the comparative example, 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.

[0133] [Method for Evaluating Resistance to Wrinkling] The dynamic wrinkling rate described below was used as an indicator to evaluate the resistance to wrinkling of the napkins in the examples and comparative examples. The results are shown in Table 1 below.

[0134] 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 mannequin. First, the width of the middle region M2 (region opposite the excretory area) of the napkin to be evaluated (width before walking) was measured, the napkin was attached to panties and placed on a flat surface, 3 g of water was injected into the central region 36, and then it was attached to the female mannequin. Next, the mannequin was made to walk at a speed of 100 steps / min for 20 minutes, and during the mannequin's walking, after 3 minutes of walking, 1.5 g of defiberized horse blood was injected into the attached napkin over 15 seconds, repeating this operation 6 times, and a total of 9 g of defiberized horse blood was injected into the napkin. Then, the napkin was removed from the panties and the width of the middle region M2 (width after walking) was measured, and the dynamic twist rate (%) was calculated from the width before walking and the width after walking using the following formula. A lower dynamic twist rate indicates less twisting of the napkin, resulting in a higher rating. The defibroused horse blood used here is 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 twist rate = [{(Width of the intermediate region before walking) - (Width of the intermediate region after walking)} ÷ (Width of the intermediate region before walking)] × 100

[0135] [Method for Measuring Compression Load in the Groin Area] To evaluate the contact load exerted on the wearer by each of the napkins in the examples and comparative examples, the compression load (width compression load) in the groin area of ​​each napkin was measured. The compression load in the groin area is the compression load in the lateral (width) direction of the napkin (absorbent material) of the measurement sample, 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 compression load in the groin area serves as an indicator of the lateral flexibility of the napkin or its absorbent component. The smaller the value of the compression load in the groin area, the better the flexibility of the napkin, the less likely it is to wrinkle when worn, the less discomfort in the groin area, and the more it can improve wearing comfort, resulting in a higher evaluation.

[0136] 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 the 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 the measurement sample 100 has an extension that extends laterally outward in the direction Y 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 back sheet on the main body of the napkin, and the extension was folded back towards the back sheet to form the measurement sample 100. At this time, the width of the measurement sample 100 was adjusted to be the same as the width of the core wrap sheet, which is a component of the measurement sample 100. As shown in Figure 8(a), the measurement sample 100 was placed under the fixing string J4 such that the intermediate region M2 (region 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 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 during the compression process was measured as the crotch compression load of the measurement sample 100. The measurement conditions were a pulling speed of 50 mm / min and a height of the fixing string J4 from the mounting surface of the measurement sample 100 to 22 mm. The measurement results of the crotch compression load of the napkins in the example and comparative example are shown in Table 1 below.

[0137]

[0138] 1... Napkin (absorbent material) 2... Front sheet 3... Back sheet 3a... Underwear contact surface (non-skin side) 4... Absorbent core 4s... Lateral side edge of absorbent core 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 area M3... Rear area CL... Vertical center line X... Vertical direction (front-back direction) Y... Horizontal direction (left-right direction)

[0139] 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.

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 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, wherein the region where the absorbent exists in a plan view comprises: a central region located in the transverse center including a longitudinal center line that bisects the absorbent in the transverse direction, where the anti-slip portions are not disposed along the entire length of the longitudinal direction; an outer region located on both transverse sides including the transverse side edge of the absorbent, where the anti-slip portions are not disposed along the entire length of the longitudinal direction; and the anti-slip portions disposed between the central region and the outer region, wherein the absorbent 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 bonding the absorbent core and the non-skin side core wrap sheet, An absorbent article comprising the above, wherein the non-skin side core adhesive is present over at least the entire length in the longitudinal direction of the intermediate region, and in the region of the intermediate region where the absorbent is present in a plan view, the area ratio of the non-skin side core adhesive is higher in the region where the shear-preventing portion is present than in the central region and the outer region.

2. 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 there is no non-skin side core adhesive that adheres to the absorbent core, and the non-skin side core adhesive-free region extends over the entire length in the longitudinal direction of at least the intermediate region, as described in claim 1.

3. 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 has a core wrap non-adhesion region between the first core wrap sheet and the second core wrap sheet that are not adhered to each other, the core wrap non-adhesion region extends over at least the entire length in the longitudinal direction of the intermediate region, and the non-skin side core wrap sheet has a double-sided non-adhesion region in which the core wrap non-adhesion region and the non-skin side core adhesive-free region overlap in a plan view, as described in claim 2.

4. The absorbent article according to claim 3, 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.

5. The absorbent article according to claim 1 or 2, wherein the absorbent core has a rigidity change portion extending in the lateral direction, and the rigidity change portion is located in the front region when the rear region is divided into two equal parts in the longitudinal direction.

6. The absorbent core has a rigidity change portion extending in the lateral direction, the rigidity change portion is located in the front region when the rear region is divided into two equal parts in the longitudinal direction, the absorbent core has a high basis weight portion and a low basis weight portion where the basis weight of the constituent material constituting the absorbent core is relatively high, the rigidity 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 longitudinally backward, extending diagonally backward from each of the lateral edges of the absorbent core toward the longitudinal center line, and 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, as described in claim 3.

7. The absorbent article according to claim 6, wherein the boundary is formed by the difference in thickness between the high-basis-weight portion and the low-basis-weight portion, the boundary is located on the non-skin side of the absorbent core, the surface sheet and the absorbent further comprise a recess that recesses toward the back sheet side, the recess reaches the non-skin side core wrap sheet, and is arranged to straddle the boundary in the longitudinal direction in a region that overlaps with the anti-slip portion in a plan view.

8. The absorbent article according to claim 1 or 2, further comprising: a skin-side core wrap sheet covering the skin-side surface of the absorbent core; and a skin-side core adhesive for bonding the absorbent core and the skin-side core wrap sheet, wherein the skin-side core adhesive is present over at least the entire length in the longitudinal direction of the intermediate region, and in the intermediate region, the lateral side 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 side edges of the coating area of ​​the skin-side core adhesive are positioned laterally inward from the lateral side edges of the coating area of ​​the non-skin-side core adhesive.

9. The absorbent article according to claim 1 or 2, wherein the absorbent core has a rigidity change portion extending laterally, and comprises an intermittent region located behind the rigidity change portion and in which the anti-slip portion is not arranged over the entire lateral region, and the non-skin side core adhesive overlaps with the intermittent region in a plan view in at least a portion thereof.

10. The absorbent article according to claim 7, further comprising a rear compression portion extending laterally within the region from the rearmost end of the anti-slip portion to the rear end of the absorbent article, wherein the surface sheet and the absorbent are integrated, and 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.

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