Absorbent article

Abstract

To provide an absorbent article in which a sheet portion having a hydrophilic fiber and disposed on the side closest to the skin around the waist is less likely to peel off an absorbent article main body even in a wet state.SOLUTION: An absorbent article (1) comprises an absorbent body (10), a front waist section (20), and a back waist section (30). At least one of the front waist section (20) and the back waist section (30) has a sheet section (25) on the side thereof closest to the skin. The sheet section (25) and an adjacent sheet member adjacent to the sheet section (25) on the non-skin side are joined by adhesion or fusion. The sheet section (25) has a skin-side layer (25a) that comes into contact with the wearer's skin, and a non-skin-side layer (25b) positioned on the non-skin side with respect to the skin-side layer (25a). The hydrophilicity of a skin-side fiber (25as), which is the base material fiber of the skin-side layer (25a), is higher than the hydrophilicity of a non-skin-side fiber (25bs), which is the base material fiber of the non-skin-side layer (25b).SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to absorbent articles.

Background Art

[0002] Conventionally, absorbent articles such as disposable diapers having a sheet for absorbing moisture such as sweat on the skin contact surface side of the waist circumference portion have been known. For example, Patent Document 1 discloses an article of clothing including a front sweat-absorbing sheet and a rear sweat-absorbing sheet on the inner surfaces of the front and rear edge portions of the front and rear waist circumference regions, each sweat-absorbing sheet being a skin contact surface of the wearer and having an inner layer containing 70 to 98% by weight of hydrophobic fibers, and an outer layer on the surface opposite to the contact surface and containing 50 to 100% by weight of hydrophilic fibers.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the article of clothing described in Patent Document 1, sweat on the front and rear parts of the waist circumference is transferred to the outer layer, and hydrophobic fibers mainly not containing sweat are brought into contact with the skin, so that even if the sweat-absorbing sheet is adhered closely to the waist circumference, sweating around the waist is prevented. However, in the case of an absorbent article in which a sheet material containing hydrophilic fibers is arranged, especially when a large amount of hydrophilic fibers are contained in the outer layer which is the non-skin side surface as in Patent Document 1, when the sheet material gets wet due to sweat or excreted fluid, the adhesive strength between the sheet material and another sheet material adjacent to the non-skin side decreases, and the sheet material may be partially peeled off. If the sheet material is peeled off, the original functions such as sweat absorption cannot be exerted, and the wearing feeling may be impaired.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide an absorbent article in which, when a sheet portion having hydrophilic fibers is disposed on the outermost skin side around the torso, the sheet portion is less likely to peel off from the absorbent article main body even when the sheet portion is wet. Means for Solving the Problems

[0006] The main invention for achieving the above object is an absorbent article having an absorbent main body, a ventral torso portion located on the ventral side of the wearer, and a dorsal torso portion located on the dorsal side of the wearer, wherein at least one of the ventral torso portion and the dorsal torso portion has a sheet portion disposed on the outermost skin side, and the sheet portion and an adjacent sheet member adjacent to the non-skin side of the sheet portion are joined by adhesion or welding. The sheet portion has a skin-side layer that contacts the skin of the wearer and a non-skin-side layer that is located on the non-skin side of the skin-side layer, and the hydrophilicity of the skin-side fibers, which are the base fibers of the skin-side layer, is higher than the hydrophilicity of the non-skin-side fibers, which are the base fibers of the non-skin-side layer. It is an absorbent article characterized by that. Other features of the present invention will be clarified by the description in this specification and the accompanying drawings. Effects of the Invention

[0007] According to the present invention, when a sheet portion having hydrophilic fibers is disposed on the outermost skin side around the torso, it is possible to provide an absorbent article in which the sheet portion is less likely to peel off from the absorbent article main body even when the sheet portion is wet. Brief Description of the Drawings

[0008]

Figure 1

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Figure 10

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Figure 13

BEST MODE FOR CARRYING OUT THE INVENTION

[0009] From the description of this specification and the attached drawings, at least the following matters become clear. Aspect 1 is an absorbent article having an absorbent main body, a ventral body circumferential part located on the ventral side of the wearer, and a dorsal body circumferential part located on the dorsal side of the wearer, the absorbent article having a sheet part disposed on at least one of the ventral body circumferential part and the dorsal body circumferential part on the most skin side, the sheet part and an adjacent sheet member adjacent to the non-skin side of the sheet part being joined by adhesion or welding, the sheet part having a skin side layer that contacts the skin of the wearer and a non-skin side layer located on the non-skin side of the skin side layer, and the hydrophilicity of the skin side fibers that are the base fibers of the skin side layer being higher than the hydrophilicity of the non-skin side fibers that are the base fibers of the non-skin side layer.

[0010] According to Aspect 1, since the hydrophilicity of the skin-side fibers in the sheet part is high, it is easy to absorb sweat and excretions. On the other hand, in the non-skin side layer, since the hydrophilicity of the non-skin side fibers, which are the base material fibers, is lower than that of the skin-side fibers, even if the sheet part gets wet, the adhesive strength with the adjacent sheet member can be maintained, preventing the sheet part from peeling off. Thereby, the original function of the sheet part can be exhibited, and it is possible to prevent the wearing feeling from being impaired due to the peeling of the sheet part.

[0011] Aspect 2 is the absorbent article according to Aspect 1, wherein the content rate of the skin-side fibers in the sheet part is 50 mass% or less.

[0012] According to Aspect 2, if the mass ratio of the skin-side fibers with high hydrophilicity becomes too high in the entire sheet part, when the sheet part gets wet, the adhesive strength with the adjacent sheet member may become weak. However, by reducing the mass ratio of the skin-side fibers in the entire sheet part, this can be avoided.

[0013] Aspect 3 is the absorbent article according to Aspect 1 or 2, wherein at least a part of the skin-side fibers in the skin-side layer is present on the same surface as the non-skin side surface of the non-skin side layer.

[0014] According to Aspect 3, the moisture absorbed by the skin-side layer can be quickly transferred to the non-skin side layer along the extending skin-side fibers. Thereby, the excessive moisture in the skin-side layer can be removed to the non-skin side layer. Since the non-skin side layer has a low ratio of skin-side fibers, it does not retain too much of the transferred moisture and can maintain the adhesive strength with the adjacent sheet member. Therefore, it is possible to prevent the wearing feeling from being impaired due to unexpected peeling of the sheet part.

[0015] Aspect 4 is the absorbent article according to any one of Aspects 1 to 3, wherein the average fiber length of the skin-side fibers in the skin-side layer is shorter than the average fiber length of the non-skin side fibers in the non-skin side layer.

[0016] According to Aspect 4, since the average fiber length of the skin-side fibers in the skin-side layer is short, it is easy to enter the gaps between the non-skin-side fibers in the non-skin-side layer, and along the entered skin-side fibers, the moisture absorbed in the skin-side layer can be quickly transferred to the non-skin-side layer. Further, since the average fiber length of the non-skin-side fibers in the non-skin-side layer is longer, the bonding strength with the adjacent sheet member can be increased. Therefore, while removing excessive moisture from the skin-side layer, the occurrence of unexpected peeling of the sheet part can be prevented.

[0017] Aspect 5 is an absorbent article according to any one of Aspects 1 to 4, wherein when a site where fibers are welded to each other in the skin-side layer and the non-skin-side layer is defined as a welded part, the total volume of the welded parts per unit volume of the non-skin-side layer is larger than the total volume of the welded parts per unit volume of the skin-side layer.

[0018] According to Aspect 5, since the skin-side layer has few (or no) welded parts, moisture easily enters between the fibers, and it is easy to absorb moisture from the wearer's skin. On the other hand, since the non-skin-side layer has welded parts, the smoothness of the surface is ensured, and it is easy to maintain the bonding strength even when the sheet part is wet. Further, since the presence of welded parts in the non-skin-side layer improves the strength of the entire sheet part, the adhesion with the adjacent sheet member can be made difficult to peel off.

[0019] Aspect 6 is an absorbent article according to Aspect 5, wherein the ratio of the total volume of the welded parts in the total volume of the non-skin-side layer is 5% or more and 25% or less.

[0020] According to Aspect 6, since the welded parts exist at such a ratio, the non-skin-side layer ensures the smoothness of the surface, it is easy to maintain the bonding strength even when the sheet part is wet, and the strength of the entire sheet part is improved. Thereby, the adhesion with the adjacent sheet member is made difficult to peel off.

[0021] Aspect 7 is the absorbent article according to any one of Aspects 1 to 6, wherein the non-skin side layer has a non-skin side layer skin side portion located on the skin side and a non-skin side layer non-skin side portion located on the non-skin side in the thickness direction of the non-skin side layer, and the fiber density of the non-skin fibers in the non-skin side layer non-skin side portion is higher than the fiber density of the non-skin fibers in the non-skin side layer skin side portion.

[0022] According to Aspect 7, the non-skin side layer non-skin side portion is the portion on the side that adheres to the adjacent sheet member. By having a higher fiber density in the non-skin side portion, the adhesion strength with the adjacent sheet member can be increased.

[0023] Aspect 8 is the absorbent article according to any one of Aspects 1 to 6, wherein the non-skin side layer has a non-skin side layer skin side portion located on the skin side and a non-skin side layer non-skin side portion located on the non-skin side in the thickness direction of the non-skin side layer, and the fiber density of the non-skin fibers in the non-skin side layer skin side portion is higher than the fiber density of the non-skin fibers in the non-skin side layer non-skin side portion.

[0024] According to Aspect 8, a higher fiber density makes it easier to draw in liquid. When the fiber density of the non-skin side layer skin side portion is high, a portion with a high fiber density of the non-skin fibers is arranged adjacent to the skin side layer with a high hydrophilicity. In this way, the moisture absorbed by the skin side fibers can be drawn into the non-skin side layer skin side portion, reducing the moisture content of the skin side layer and suppressing the stickiness feeling of the portion touching the skin.

[0025] Aspect 9 is the absorbent article according to any one of Aspects 1 to 8, wherein the non-skin side layer has a non-skin side layer skin side portion located on the skin side and a non-skin side layer non-skin side portion located on the non-skin side in the thickness direction of the non-skin side layer, and the hydrophilicity of the non-skin fibers in the non-skin side layer skin side portion is higher than the hydrophilicity of the non-skin fibers in the non-skin side layer non-skin side portion.

[0026] According to Aspect 9, the skin-side portion of the non-skin layer is the portion on the side that contacts the skin-side fibers of the skin layer. By increasing the hydrophilicity of the non-skin fibers in the skin-side portion of the non-skin layer, it becomes easier for moisture to transfer from the skin-side fibers to the non-skin fibers. The transferred moisture is less likely to stay in the non-skin-side portion of the non-skin layer with low hydrophilicity and is more likely to promote evaporation. Since it is difficult for moisture to accumulate in the non-skin-side portion of the non-skin layer, it becomes easier to maintain the adhesion between the non-skin layer and the adjacent sheet member.

[0027] Aspect 10 is the absorbent article according to any one of Aspects 1 to 9, wherein the skin-side fibers are cotton fibers, and the non-skin fibers are hydrophobic fibers containing at least any one of polypropylene, polyethylene, and polyurethane, or fibers obtained by hydrophilizing at least any one of polypropylene, polyethylene, and polyurethane.

[0028] According to Aspect 10, the skin layer contains cotton fibers, making it easier to absorb moisture from the skin. The non-skin layer contains the above hydrophobic fibers (or hydrophilized fibers), so that after excessive moisture in the skin layer transfers to the non-skin layer, it does not retain moisture excessively and promotes evaporation more towards the non-skin side. Thereby, the adhesion strength with the adjacent sheet member is maintained, preventing the wearing feeling from being impaired due to unexpected peeling of the sheet portion.

[0029] Aspect 11 is the absorbent article according to any one of Aspects 1 to 10, wherein the skin layer has a predetermined basis weight portion provided with the skin-side fibers having a predetermined basis weight and a low basis weight portion having a lower basis weight of the skin-side fibers than the predetermined basis weight portion.

[0030] According to Aspect 11, the predetermined basis weight portion is a portion with good absorbency and feel on the skin, and also, since moisture such as sweat absorbed from the skin side is more likely to move from the low basis weight portion to the non-skin side, moisture is not accumulated in the skin layer and evaporation can be promoted.

[0031] Aspect 12 is the absorbent article according to Aspect 11, wherein the non-skin side layer has a predetermined basis weight portion provided with the non-skin side fibers of a predetermined basis weight and a low basis weight portion having a lower basis weight of the non-skin side fibers than the predetermined basis weight portion, and the low basis weight portion of the skin side layer and the low basis weight portion of the non-skin side layer have an overlapping portion when viewed in the thickness direction of the absorbent article.

[0032] According to Aspect 12, in the overlapping portion, it promotes drawing the moisture absorbed by the skin side layer from the low basis weight portion of the skin side layer to the low basis weight portion of the non-skin side layer, and can maintain the adhesive strength by removing the moisture from the sheet portion more quickly, thereby preventing the occurrence of peeling of the sheet portion.

[0033] ===Embodiment=== Hereinafter, as an example of the absorbent article according to the present embodiment, an adult disposable pant diaper 1 (hereinafter, also simply referred to as "diaper 1") will be described as an example. However, the absorbent article according to the present embodiment is not limited to the above, and can be applied, for example, as a disposable pant diaper for infants, a short-type napkin, a tape-type disposable diaper, or the like. <Basic configuration of disposable pant diaper 1> FIG. 1 is a schematic perspective view of diaper 1 seen from the ventral side. FIG. 2 is a schematic plan view of diaper 1 in a deployed and stretched state seen from the skin side of the wearer. FIG. 3 is a schematic cross-sectional view taken along line A-A in FIG. 2.

[0034] The "deployed state" of diaper 1 means a state in which the diaper 1 in the pant shape of FIG. 1 is unfolded by releasing the joining of side joining portions SS (described later) provided on both sides in the left-right direction, separating the ventral body surrounding portion 20 (described later) and the dorsal body surrounding portion 30 (described later), and opening diaper 1 in the vertical direction to deploy diaper 1 on a plane. The "stretched state" of diaper 1 means a state in which the product (diaper 1) is stretched without wrinkles, specifically, a state in which the dimensions of each member constituting diaper 1 (for example, the absorbent main body 10, the ventral body surrounding portion 20, etc.) are extended until they match or are close to the dimensions of the member alone.

[0035] The diaper 1 has a pant-like shape when worn as shown in FIG. 1, having vertical, horizontal, and front-back directions that intersect with each other, and a waist opening BH and a pair of leg openings LH. In the vertical direction, the side of the waist opening BH is the upper side, and the side that becomes the crotch side of the wearer is the lower side. In the front-back direction, the side that becomes the front side of the wearer is the front side, and the side that becomes the back side is the back side. Also, in the unfolded and extended state shown in FIG. 2, the diaper 1 has a longitudinal direction, a horizontal direction, and a thickness direction (the direction penetrating the paper surface in FIG. 2) as three mutually orthogonal directions. Note that the longitudinal direction is along the aforementioned vertical direction. And one side of the longitudinal direction corresponds to the front side (ventral side), and the other side corresponds to the back side (dorsal side). Further, as shown in FIG. 3, the diaper 1 has a thickness direction in which materials are laminated, and the side that contacts the wearer in the thickness direction is the skin side, and the opposite side is the non-skin side.

[0036] The diaper 1 has an absorbent body 10 and an outer cover 18. The outer cover 18 has a pair of waist portions 20, 30 and a crotch portion 40 located at the crotch of the wearer. The outer cover 18 is joined to the non-skin side surface of the absorbent body 10 with an adhesive or the like. Among the pair of waist portions 20, 30, the one located on the front side (ventral side) of the wearer is also called the ventral waist portion 20, and the one located on the back side (dorsal side) is also called the dorsal waist portion 30. The ventral waist portion 20 and the dorsal waist portion 30 are joined by a pair of side joints SS at both side portions in the horizontal direction. Examples of the joining method by the side joints SS include heat welding, ultrasonic welding, and a joining method using an adhesive.

[0037] As shown in Fig. 3, the absorbent body 10 has an absorbent core 11, a liquid-permeable topsheet 12 disposed closer to the skin side than the absorbent core 11, a liquid-impermeable backsheet 13 disposed closer to the non-skin side than the absorbent core 11, and an outer wrapper sheet 14. The absorbent core 11 may be any material that can absorb and hold excreted fluids. Examples include those formed by shaping liquid-absorbent materials such as pulp fibers and superabsorbent polymers (SAP) into a predetermined shape. The absorbent core 11 may also be covered with a liquid-permeable sheet such as tissue paper or non-woven fabric. The topsheet 12 is formed of, for example, a non-woven fabric such as an air-through non-woven fabric or a spunbond non-woven fabric. The backsheet 13 is, for example, a liquid-impermeable and breathable film such as polyethylene or polypropylene. The outer wrapper sheet 14 is formed of, for example, a non-woven fabric equivalent to the topsheet 12.

[0038] As shown in Fig. 2, on both sides of the absorbent body 10 in the left-right direction, a plurality of elastic members 15 (e.g., thread rubber) that stretch along the longitudinal direction of the absorbent body 10 are provided around the legs. Further, an anti-leakage wall portion that can stand up on the skin side may be provided by providing, for example, an elastic member that stretches in the longitudinal direction inside the elastic members 15 around the legs in the left-right direction.

[0039] As shown in Figs. 2 and 3, the outer package 18 has an inner layer sheet 21, a ventral outer layer sheet 22 (outer layer sheet), and a dorsal outer layer sheet 32 (outer layer sheet).

[0040] The inner layer sheet 21 is disposed from the ventral body circumference portion 20 through the crotch portion 40 to the dorsal body circumference portion 30 (Fig. 3). The width (length in the left-right direction) of the inner layer sheet 21 at the ventral body circumference portion 20 and the dorsal body circumference portion 30 is larger than the width (length in the left-right direction) of the inner layer sheet 21 at the crotch portion 40 (Fig. 2). As the inner layer sheet 21, an air-through non-woven fabric, a spunbond non-woven fabric, an SMS non-woven fabric (spunbond - meltblown - spunbond non-woven fabric), a waterproof film, etc. can be used.

[0041] As shown in FIGS. 2 and 3, the ventral outer layer sheet 22 is provided on the non-skin side of the inner layer sheet 21, and the ventral outer layer sheet 22 and the inner layer sheet 21 constitute the ventral body circumferential portion 20. The outer end (upper end) of the ventral outer layer sheet 22 in the longitudinal direction is folded back to the skin side. The folded portion 22r of the ventral outer layer sheet 22 wraps around one end (outer end) of the inner layer sheet 21 in the longitudinal direction. Note that the outer end (upper end) of the ventral outer layer sheet 22 in the longitudinal direction may not be folded back.

[0042] Similarly, as shown in FIGS. 2 and 3, the dorsal outer layer sheet 32 is provided on the non-skin side of the inner layer sheet 21, and the dorsal outer layer sheet 32 and the inner layer sheet 21 constitute the dorsal body circumferential portion 30. The outer end (upper end) of the dorsal outer layer sheet 32 in the longitudinal direction is folded back to the skin side. The folded portion 32r of the dorsal outer layer sheet 32 wraps around the other end (outer end) of the inner layer sheet 21 in the longitudinal direction. Note that the outer end (upper end) of the dorsal outer layer sheet 32 in the longitudinal direction may not be folded back.

[0043] As the ventral outer layer sheet 22 and the dorsal outer layer sheet 32, an air-through nonwoven fabric, a spunbond nonwoven fabric, an SMS nonwoven fabric (spunbond - meltblown - spunbond nonwoven fabric), etc. can be used.

[0044] The ventral body circumferential portion 20 and the dorsal body circumferential portion 30 each have body circumferential elastic members 23, 33 that can expand and contract in the left - right direction. The plurality of body circumferential elastic members 23, 33 are arranged at intervals in the up - down direction between the inner layer sheet 21 and the ventral outer layer sheet 22, and between the inner layer sheet 21 and the dorsal outer layer sheet 32, and are fixed in an extended state in the left - right direction (see FIGS. 2 and 3). Therefore, the ventral body circumferential portion 20 and the dorsal body circumferential portion 30 expand and contract in the left - right direction and fit around the wearer's body circumference. Note that examples of the body circumferential elastic members 23, 33 include thread - like elastic members such as rubber threads and elongated elastic sheets.

[0045] In addition, in the present embodiment, in the dorsal trunk portion 30, the hind leg around elastic member 34 is provided between the inner layer sheet 21 and the dorsal outer layer sheet 32. The hind leg around elastic member 34 may be, for example, a plurality of thread rubbers, an elastic sheet in a belt shape having elasticity, or the like. The hind leg around elastic member 34 is joined and fixed by an adhesive such as a hot melt adhesive in an extended state.

[0046] In the present embodiment, in a predetermined region on the most skin side of the ventral trunk portion 20 and the dorsal trunk portion 30, sheet portions 25 and 35 that are easy to absorb the sweat of the wearer are provided (the hatched portions in FIG. 2). The sheet portions 25 and 35 are arranged closer to the skin side than the absorbent body 10, and are strip-shaped sheet members that are shorter in the vertical direction than the inner layer sheet 21, the ventral and dorsal outer layer sheets 22 and 32, etc., and are arranged to cover the longitudinal ends of the absorbent body 10. Details of the sheet portions 25 and 35 will be described later.

[0047] The basic configuration of the diaper 1 has been described above, but the configuration of the diaper 1 described above is an example and is not limited thereto. For example, in the diaper 1 of the present embodiment, the outer package 18 having three parts, the ventral trunk portion 20, the dorsal trunk portion 30, and the crotch portion 40 connecting them, is provided. However, the present invention is not limited to this. For example, the ventral trunk portion 20 and the dorsal trunk portion 30 may be configured as separate members, and the diaper may have a configuration in which the non-skin side surface of the absorbent body 10 is exposed in the crotch portion, or the diaper may have an outer package member configured as a single member continuous from the ventral trunk portion 20 to the dorsal trunk portion 30.

[0048] <Regarding the sheet portions 25 and 35> Hereinafter, the specific configurations of the sheet portions 25 and 35 according to this embodiment will be described. In this embodiment, the sheet portion 25 provided in the ventral body circumferential portion 20 and the sheet portion 35 provided in the dorsal body circumferential portion 30 have substantially the same configuration. Therefore, in the following description, for the content common to both the sheet portion 25 and the sheet portion 35, only the sheet portion 25 will be described on behalf of both. For the sheet portion 35, specific descriptions will be omitted, such as indicating the reference numerals of the members corresponding to the sheet portion 25 in parentheses as necessary.

[0049] FIG. 4 is a schematic cross-sectional view of the sheet portion 25. As described above, the sheet portion 25 in this embodiment constitutes a part of the surface that contacts the wearer's skin in the ventral body circumferential portion 20 (FIG. 3). And as shown in FIG. 4, the sheet portion 25 has a skin-side layer 25a arranged to contact the wearer's skin and a non-skin-side layer 25b located on the non-skin side in the thickness direction of the skin-side layer 25a.

[0050] In this embodiment, the skin-side fibers, which are the base fibers of the skin-side layer 25a, are cotton fibers. Note that the above-mentioned "base material" means a material whose mass ratio in each layer (skin-side layer 25a, non-skin-side layer 25b) exceeds 50%. As the non-skin-side fibers, which are the base fibers of the non-skin-side layer 25b, polyester fibers, polypropylene fibers, polyethylene fibers, polyurethane fibers, or composite fibers thereof, etc., whose fiber surfaces are hydrophilized, are used. Note that each of the fibers listed as the above-mentioned non-skin-side fibers may not be subjected to hydrophilization treatment.

[0051] In the sheet member constituting the sheet portion 25 of this embodiment, the skin-side fibers 25as, which are the base fibers of the skin-side layer 25a, are entangled with the non-skin-side fibers 25bs, which are the base fibers of the non-skin-side layer 25b (FIG. 4). As a method of integrating the skin-side layer 25a and the non-skin-side layer 25b by entanglement, for example, a known water jet entanglement method or the like can be used.

[0052] As described above, the sheet member (sheet portion 25) is formed by the entanglement of fibers in each layer. In the skin-side layer 25a of the present embodiment, all fibers except the non-skin-side fibers 25bs that have entered the skin-side layer 25a are cotton fibers. However, it is not limited to this, and the skin-side layer 25a may have cotton fibers exceeding 50% by mass, and preferably may have cotton fibers exceeding 80% by mass.

[0053] In addition, in the present embodiment, in the process of integrating the skin-side layer 25a and the non-skin-side layer 25b using the water flow entanglement method as described above, the hydrophilizing agent applied to the surface of the base fibers of the non-skin-side layer 25b is partially removed by the water flow. Therefore, the non-skin-side fibers bs of the non-skin-side layer 25b in the present embodiment include fibers in which the hydrophilizing agent has been completely removed to become hydrophobic fibers, fibers in which a part of the hydrophilizing agent has been removed but the hydrophilizing agent remains partially, and fibers in which the hydrophilizing agent remains completely.

[0054] Therefore, in the sheet portion 25 of the present embodiment, the hydrophilicity of the skin-side fibers 25as, which are the base fibers of the skin-side layer 25a, is higher than the hydrophilicity of the non-skin-side fibers 25bs, which are the base fibers of the non-skin-side layer 25b. And the sheet portion 25 can be used as a part for absorbing the sweat of the wearer. When the diaper 1 is worn, the sweat adhering to the skin is first absorbed from the skin-side layer 25a, and the absorbed sweat migrates to the non-skin-side layer 25b side. By disposing the skin-side layer 25a having the skin-side fibers 25as with high hydrophilicity as the base material on the surface in contact with the skin of the wearer, the water absorption is improved. Also, since the hydrophilicity of the non-skin-side fibers 25bs of the non-skin-side layer 25b is lower than that of the cotton fibers as, when the moisture such as sweat absorbed by the cotton fibers as moves to the non-skin side, the non-skin-side layer 25b promotes transpiration without excessively retaining moisture, making the sheet portion 25 less stuffy. By disposing such a sheet portion 25 (35) on the ventral body circumference portion 20 (dorsal body circumference portion 30), the occurrence of skin troubles such as eczema, chafing, and rash can be suppressed.

[0055] The "hydrophilicity" of the above-mentioned fibers is evaluated based on the contact angle of the fibers measured by the following method. Specifically, the smaller the measured contact angle, the higher the hydrophilicity, and the larger the contact angle, the lower the hydrophilicity. <Method for Measuring Contact Angle> (1) First, cotton fibers and non-skin-side fibers are taken out from predetermined parts of each layer. The taken-out fibers are cut to a fiber length of 10 mm, and five fibers of each are prepared as samples. (2) As the measuring device, an automatic minimum contact angle meter MCA-J manufactured by Kyowa Interface Science Co., Ltd. is used, and the measuring environment is set at room temperature of 22 ± 2°C and humidity of 65 ± 2%RH. (3) Place the sample on the measuring device, drop 20 picoliters of distilled water (micro-droplet) from the inkjet head mounted on the device onto the surface of the fiber, and record the state of the micro-droplet over time. (4) Analyze the image immediately after the micro-droplet adheres to the surface of the fiber, and calculate the contact angle of the micro-droplet with respect to the fiber surface. (5) Measure the contact angles at 20 different locations for each fiber. Measure the contact angles of the five samples, and adopt the average value of the 100 measurement values in total as the contact angle. In addition, when the layer (sheet) to be measured is joined to other members by an adhesive, fusion, etc., the joined part is taken out after weakening the adhesive force with a cooling means such as cold spray within a range that does not affect the contact angle of the fiber.

[0056] In addition, when comparing the "fibers with the hydrophilizing agent completely remaining" among the non-skin-side fibers bs of the non-skin-side layer 25b described above by the above evaluation method, the skin-side fibers 25as of the skin-side layer 25a have higher hydrophilicity.

[0057] The thickness of each of the skin-side layer 25a and the non-skin-side layer 25b is, for example, preferably about 0.3 mm to 0.4 mm for the skin-side layer 25a and preferably about 0.1 mm for the non-skin-side layer 25b.

[0058] FIG. 5 is a plan view showing an adhesive for joining the sheet portion 25 and an adjacent sheet member adjacent to the non-skin side of the sheet portion 25. FIG. 6 is a view schematically showing a cross section from the sheet portion 25 to the folded-back portion 22r at the position of X in FIG. 5. In the present embodiment, as shown in FIG. 5, a joint portion 50x is provided in which the sheet portion 25 and an adjacent sheet member adjacent to the non-skin side in the thickness direction of the sheet portion 25 are joined by a hot-melt adhesive. The "adjacent sheet member" in the ventral body circumferential portion 20 is the top sheet 12 in the region where the sheet portion 25 and the absorbent body 10 overlap in the vertical direction (longitudinal direction), and is the folded-back portion 22r of the ventral outer layer sheet 22 in the region above the absorbent body 10. The joint portion 50x of the present embodiment is provided by applying a hot-melt adhesive in a spiral pattern extending along the left-right direction and arranged in two rows in the vertical direction, but the number and application pattern are not limited to this. For example, in addition to applying an adhesive such as a hot-melt adhesive by a non-contact application method, the joint portion 50x may be provided by thermal welding or ultrasonic welding.

[0059] Further, the ventral body circumferential portion 20 has a non-joint portion 50z in which the sheet portion 25 and the adjacent sheet member (the top sheet 12 or the folded-back portion 22r of the ventral outer layer sheet 22) are not joined by adhesion or the like.

[0060] Thus, in the case of an absorbent article such as a diaper 1 in which a sheet portion 25 (sheet member) containing hydrophilic fibers such as cotton fibers is disposed on the skin-contact surface, there are advantages such as improved sweat absorption and skin feel. However, on the other hand, when the sheet member is wetted by sweat or excreted liquid, etc., the adhesive strength of the joint portion joining the sheet member and the absorbent article body decreases, and the sheet member may be partially peeled off. If the sheet member is partially peeled off, the original function of the sheet member may not be exhibited, and thereby the wearing feeling may be impaired.

[0061] As described above, in the sheet portion 25 of the present embodiment, the hydrophilicity of the skin-side fibers 25as, which are the base fibers of the skin-side layer 25a of the sheet portion 25, is higher than the hydrophilicity of the non-skin-side fibers 25bs, which are the base fibers of the non-skin-side layer 25b. Thus, the skin-side layer 25a easily absorbs sweat and excretions. When the sheet portion 25 contains moisture such as sweat, the adhesive itself at the joint portion 50x where the sheet portion 25 is joined to the folded portion 22r of the ventral outer layer sheet 22 or the top sheet 12 may become wet, resulting in a possible decrease in adhesive strength. However, since the hydrophilicity of the non-skin-side fibers 25bs of the non-skin-side layer 25b is lower than that of the skin-side fibers 25as, even when the sheet portion 25 gets wet, the adhesive strength at the joint portion 50x can be maintained, preventing the sheet portion 25 from peeling off. Thereby, the sheet portion 25 can exhibit its original function, and it is possible to prevent the wearing feeling from being impaired due to the peeling of the sheet portion 25.

[0062] Also, different from the present embodiment, even when the joint portion 50x between the sheet portion 25 and the folded portion 22r disposed on the non-skin side of the sheet portion 25 or the top sheet 12 is joined by welding, when the sheet portion 25 absorbs sweat or the like and becomes in a state containing moisture, it is conceivable that the entanglement strength that had entangled the fibers decreases, making the sheet portion 25 more likely to peel off. However, since the hydrophilicity of the non-skin-side fibers 25bs is lower than that of the skin-side fibers 25as, the non-skin-side fibers 25bs are less likely to remain in a state containing moisture, and thus it is difficult to lower the entanglement strength. Therefore, it is possible to avoid the sheet portion 25 from peeling off.

[0063] Here, the adhesive strength of the joint portion in the wet state was compared by the following method. <Adhesive Strength Evaluation Method> 1) First, as a sample of the member adjacent to the sheet portion 25 from the non-skin side, a spunbond nonwoven fabric for the outer layer is used. A plurality of spunbond nonwoven fabrics for the outer layer with a size of 50 mm × 25 mm are prepared. 2) For the evaluation, samples obtained by bonding the above-mentioned spunbond nonwoven fabric for the outer layer to each of the following three samples are used. a) The surface of the non-skin-side layer 25b of the sheet member constituting the sheet portion 25 (Example) b) Hydrophobic spunbond nonwoven fabric (100% synthetic fiber) (Comparative Example 1) c) Surface of the skin-side layer 25a of the sheet member constituting the sheet portion 25 (Comparative Example 2) Prepare three sheets each with a size of 50 mm × 25 mm for each of the sheets a) to c) above. Apply a hot melt adhesive to the outer layer spunbond nonwoven fabric and each of the sheets (or surfaces) of a) to c) in the same pattern as the joint portion 50x and bond them to produce each sample. Prepare three samples each for the bonded samples (Examples, Comparative Example 1, Comparative Example 2). 3) Place each sample on the water surface so that the surfaces of a) to c) of each sample face downward (that is, the outer layer spunbond nonwoven fabric side is on the side opposite to the water surface), and leave it for 10 minutes. 4) Pull each sample pulled out from the water surface with a tensile testing machine so as to peel the outer layer spunbond nonwoven fabric and each of the sheets of a) to c) in the 180° direction, and measure the load value. 5) Take the average value of the measured load values as the adhesive strength (N).

[0064] The average values obtained by the above measurement method were higher in the order of Comparative Example 1, Example, and Comparative Example 2. Specifically, Comparative Example 1 was 3.58 N, the Example was 2.50 N, and Comparative Example 2 was 0.73 N. From this, it was found that the more cotton fibers there were on the bonding surface, the lower the adhesive strength became.

[0065] Therefore, in the present embodiment, since the non-skin-side layer 25b with fewer cotton fibers and the folded-back portion 22r of the ventral outer layer sheet 22 are joined at the joint portion 50x, even when the sheet portion 25 contains moisture, the adhesive strength of the joint portion 50x is less likely to decrease, and the sheet portion 25 is less likely to peel off.

[0066] Also, throughout the entire sheet portion 25, the content rate of the skin-side fibers 25as may be 50% by mass or less. If the mass ratio of the skin-side fibers 25as with high hydrophilicity becomes too high throughout the entire sheet portion 25, when the sheet portion 25 gets wet due to sweat or the like, the adhesive strength with the top sheet 12, the folded-back portion 22r of the ventral outer layer sheet 22, etc., which are adjacent sheet members, may become weak. However, by lowering the mass ratio of the skin-side fibers 25as throughout the entire sheet portion 25, this can be avoided.

[0067] In addition, in order to compare the masses of the respective fibers throughout the entire sheet portion 25, it is necessary to separate the skin-side fibers 25as and the non-skin-side fibers 25bs. As a separation method, the sheet member that is the sheet portion 25 is immersed in water and stirred for 24 hours, whereby the skin-side fibers 25as and the non-skin-side fibers 25bs can be separated.

[0068] Also, as shown in FIGS. 4 and 6, the skin-side layer 25a and the non-skin-side layer 25b are laminated in the thickness direction, but at least a part of the skin-side fibers 25as of the skin-side layer 25a exists on the same surface as the non-skin-side surface of the non-skin-side layer 25b. That is, the skin-side fibers 25as of the skin-side layer 25a are intertwined with the non-skin-side fibers 25bs, and at least a part of them extends into the non-skin-side layer 25b. Moreover, a part of the extending skin-side fibers 25as exists on the same surface as the non-skin-side surface of the non-skin-side layer 25b. In this way, since the skin-side fibers 25as exist in the non-skin-side layer 25b, the moisture absorbed by the skin-side layer 25a can be quickly transferred to the non-skin-side layer 25b along the extending skin-side fibers 25as. Thereby, the excessive moisture in the skin-side layer 25a can be removed to the non-skin-side layer 25b. On the other hand, since the non-skin-side layer 25b has a low ratio of non-skin-side fibers 25bs, it does not hold too much of the transferred moisture, and the adhesive strength with the folded-back portion 22r of the ventral outer layer sheet 22 or the top sheet 12 (adjacent sheet member) adjacent to the non-skin side can be maintained. Therefore, it is possible to prevent the wearing feeling from being impaired due to the unexpected peeling of the sheet portion 25.

[0069] Conversely, at least a part of the non-skin-side fibers 25bs of the non-skin-side layer 25b extends into the skin-side layer 25a, and furthermore, among the non-skin-side fibers 25bs, some are present on the same surface as the skin-side surface of the skin-side layer 25a. Thereby, the absorbed liquid easily transfers from the skin-side layer 25a to the non-skin-side layer 25b along the non-skin-side fibers 25bs extending in the skin-side layer 25a, and the transferred moisture is less likely to stay in the non-skin-side layer 25b with low hydrophilicity and is more likely to promote transpiration.

[0070] Also, the average fiber length of the skin-side fibers 25as in the skin-side layer 25a is shorter than the average fiber length of the non-skin-side fibers 25bs in the non-skin-side layer 25b. Since the average fiber length of the skin-side fibers 25as in the skin-side layer 25a is short, it is easy to enter the gaps between the non-skin-side fibers 25bs in the non-skin-side layer 25b, and the moisture absorbed in the skin-side layer 25a can be quickly transferred to the non-skin-side layer 25b along the entered skin-side fibers 25as. Also, since the average fiber length of the non-skin-side fibers 25bs in the non-skin-side layer 25b is longer, the bonding strength with the folded-back portion 22r of the ventral outer layer sheet 22 adjacent to the non-skin side or the top sheet 12 (adjacent sheet member) can be increased. Therefore, while removing excessive moisture from the skin-side layer 25a, it is possible to prevent the occurrence of unexpected peeling of the sheet portion 25.

[0071] Note that the average fiber length means the length-weighted average fiber length measured by the central fiber length (Cont). The length-weighted average fiber length is measured as the L(l) value by the Kajaani FiberLab fiber properties (off-line) manufactured by Metso Automation. This is also a method recommended by JIS P 8226-2 (Pulp - Fiber length measurement method by engineering automatic analysis method - Conforming to the non-polarization method).

[0072] In addition, when the sheet part 25 of the present embodiment forms the skin-side layer 25a and the non-skin-side layer 25b by water entanglement, the kinetic energy of the water flow may be converted into thermal energy, causing the fibers to melt. Particularly in the non-skin-side layer 25b, since each of the fibers exemplified as the base fibers is a thermoplastic resin fiber, welded parts (not shown) where the fibers are partially welded to each other are formed by water entanglement. Since the base fibers of the skin-side layer 25a are cotton fibers, melting does not occur between the cotton fibers due to the water flow. However, melting occurs in the non-skin-side fibers 25bs that have entered the skin-side layer 25a due to entanglement, and welded parts may also be formed in a form that entraps the skin-side fibers 25as that are entangled with such melted non-skin-side fibers 25bs. Thus, welded parts where the fibers are welded to each other exist in the skin-side layer 25a and the non-skin-side layer 25b. However, since the base fibers of the non-skin-side layer 25b are thermoplastic resin fibers, the total volume of the welded parts per unit volume of the non-skin-side layer 25b is larger than the total volume of the welded parts per unit volume of the skin-side layer 25a. Note that the "total volume of the welded parts per unit volume of the skin-side layer 25a" includes the case where the total volume of the welded parts is zero. Further, the ratio of the total volume of the welded parts in the entire volume of the above-described non-skin-side layer 25b is preferably 5% or more and 25% or less. Since the skin-side layer 25a has few (or no) welded parts, moisture easily enters between the fibers, and it easily absorbs moisture from the skin of the wearer. On the other hand, since the non-skin-side layer 25b has welded parts, it ensures surface smoothness and easily maintains adhesive strength even when the sheet part 25 is wet. Further, since the presence of welded parts in the non-skin-side layer 25b improves the strength of the entire sheet part 25, it is possible to make it difficult to peel the adhesion between the folded-back part 22r adjacent to the non-skin side or the top sheet 12 (adjacent sheet member).

[0073] As shown in FIG. 6, the non-skin side layer 25b has a non-skin side layer skin side portion 25bA located on the skin side and a non-skin side layer non-skin side portion 25bB located on the non-skin side in the thickness direction of the non-skin side layer 25b. The sheet member constituting the sheet portion 25 of the present embodiment is formed by entangling the skin side fibers 25as of the skin side layer 25a and the non-skin side fibers 25bs of the non-skin side layer 25b by water flow entanglement. When performing water flow entanglement, water flows are applied from both the skin side of the skin side layer 25a and the non-skin side of the non-skin side layer 25b. That is, in the non-skin side layer 25b, since water flow is applied from the non-skin side layer non-skin side portion 25bB side, when comparing the non-skin side fibers 25bs of the non-skin side layer skin side portion 25bA and the non-skin side fibers 25bs of the non-skin side layer non-skin side portion 25bB, the fiber density of the non-skin side fibers 25bs of the non-skin side layer skin side portion 25bA is higher than the fiber density of the non-skin side fibers 25bs of the non-skin side layer non-skin side portion 25bB. Since a higher fiber density makes it easier to draw in liquid, as in the present embodiment, by arranging a portion (non-skin side layer skin side portion 25bA) with a high fiber density of the non-skin side fibers 25bs at a position adjacent to the skin side layer 25a with high hydrophilicity, the moisture absorbed by the skin side fibers 25as can be quickly drawn into the non-skin side layer skin side portion 25bA, reducing the moisture content of the skin side layer 25a and suppressing stickiness and the like of the portion touching the skin.

[0074] Also, the fiber densities of the non-skin side layer skin side portion 25bA and the non-skin side layer non-skin side portion 25bB are not limited to this. Conversely, the fiber density of the non-skin side fibers 25bs of the non-skin side layer non-skin side portion 25bB may be higher than the fiber density of the non-skin side fibers 25bs of the non-skin side layer skin side portion 25bA. The non-skin side layer non-skin side portion 25bB is a portion on the side that adheres to the folded-back portion 22r of the ventral outer layer sheet 22 or the top sheet 12 (adjacent sheet member) adjacent to the non-skin side. By having a higher fiber density of the non-skin side fibers 25bs of the non-skin side layer non-skin side portion 25bB, the adhesion strength with the adjacent sheet member can be increased.

[0075] Similarly, when creating the sheet member (sheet part 25) by water flow intersection, in the non-skin side layer 25b, since water flow is applied from the non-skin side part 25bB side of the non-skin side layer, the water flow makes it easier to remove the hydrophilizing agent attached to the surface of the non-skin side fibers 25bs on the non-skin side part 25bB side of the non-skin side layer than the non-skin side fibers 25bs on the skin side part 25bA side of the non-skin side layer. Therefore, the hydrophilicity of the non-skin side fibers 25bs in the skin side part 25bA of the non-skin side layer is higher than the hydrophilicity of the non-skin side fibers 25bs in the non-skin side part 25bB of the non-skin side layer. The comparison of hydrophilicity can be similarly evaluated by the above-described hydrophilicity evaluation method.

[0076] The skin side part 25bA of the non-skin side layer is the part on the side that contacts the skin side fibers 25as of the skin side layer 25a. By increasing the hydrophilicity of the non-skin side fibers 25bs in the skin side part 25bA of the non-skin side layer, it becomes easier for moisture to transfer from the skin side fibers 25as to the non-skin side fibers 25bs. The transferred moisture is less likely to stay in the non-skin side part 25bB of the non-skin side layer with low hydrophilicity and is more likely to promote transpiration. Since it is difficult for moisture to accumulate in the non-skin side part 25bB of the non-skin side layer, it becomes easier to maintain the adhesion between the non-skin side layer 25b and the folded-back part 22r or the top sheet 12 (adjacent sheet member) adjacent to the non-skin side.

[0077] As described above, in the present embodiment, the skin side fibers 25as are cotton fibers, and the non-skin side fibers 25bs are fibers obtained by hydrophilizing at least any one of polypropylene, polyethylene, and polyurethane, or may be hydrophobic fibers containing any one of polypropylene, polyethylene, and polyurethane. By including cotton fibers in the skin side layer 25a, it becomes easier to absorb moisture from the skin. And since the hydrophilicity of the non-skin side fibers 25bs of the non-skin side layer 25b is lower than that of the skin side fibers 25as, after the moisture in the skin side layer 25a transfers to the non-skin side layer 25b, it does not retain the moisture excessively and promotes transpiration more to the non-skin side. Thereby, the non-skin side layer 25b maintains the adhesion strength with the folded-back part 22r or the top sheet 12 (adjacent sheet member) adjacent to the non-skin side, and prevents the wearing feeling from being impaired by the unexpected peeling of the sheet part 25.

[0078] FIG. 7 shows an enlarged photograph of the sheet portion 25 as viewed from the skin side. FIG. 8 shows an enlarged photograph of the sheet portion 25 as viewed from the non-skin side. As shown in FIG. 4, the skin-side layer 25a has a predetermined basis weight portion 25ap including skin-side fibers 25as having a predetermined basis weight, and a low basis weight portion 25aL where the basis weight of the skin-side fibers 25as is lower than that of the predetermined basis weight portion 25ap. Here, the basis weight is the mass per unit area. FIG. 7 shows the skin-side layer 25a as viewed from the skin side. For easy understanding, some of the low basis weight portions 25aL are shown surrounded by white lines (the low basis weight portion 25aL is the portion inside the white lines). Note that the low basis weight portion 25aL in the present embodiment includes the case where the basis weight of the skin-side fibers 25as is zero. Specifically, in the low basis weight portion 25aL shown in FIG. 7, since the basis weight of the skin-side fibers 25as is low or zero, when viewed from the skin side, the non-skin-side fibers 25bs of the non-skin-side layer 25b located on the non-skin side of the skin-side layer 25a can be visually recognized.

[0079] The predetermined basis weight portion 25ap of the skin-side layer 25a is a portion with good absorbency and texture. Also, in the skin-side layer 25a, moisture such as sweat absorbed from the skin side can be easily moved from the low basis weight portion 25aL to the non-skin side, so that moisture is not accumulated in the skin-side layer 25a and transpiration can be promoted.

[0080] Similarly, the non-skin side layer 25b has a predetermined basis weight portion 25bp including non-skin side fibers 25bs with a predetermined basis weight, and a low basis weight portion 25bL where the basis weight of the non-skin side fibers 25bs is lower than that of the predetermined basis weight portion 25bp (FIG. 4). FIG. 8 shows the non-skin side layer 25b as viewed from the non-skin side. Similarly in FIG. 8, for easier understanding, some of the low basis weight portions 25bL are surrounded by white lines and shown (the low basis weight portion 25bL is the portion inside the white lines). Note that the low basis weight portion 25bL in the present embodiment includes the case where the basis weight of the non-skin side fibers 25bs is zero. Then, as shown in FIGS. 4, 7, and 8, the low basis weight portion 25aL of the skin side layer 25a and the low basis weight portion 25bL of the non-skin side layer 25b have an overlapping portion when viewed in the thickness direction of the diaper 1. In the overlapping portion, it promotes drawing the moisture absorbed by the skin side layer 25a from the low basis weight portion 25aL of the skin side layer 25a to the low basis weight portion 25bL of the non-skin side layer 25b, so that the moisture is removed more quickly from the sheet portion 25. Thereby, the adhesive strength between the sheet portion 25 and the folded-back portion 22r or the top sheet 12 (adjacent sheet member) adjacent to the sheet portion 25 from the non-skin side can be maintained, and the occurrence of peeling of the sheet portion 25 can be prevented.

[0081] Note that FIGS. 7 and 8 schematically show the low basis weight portion 25aL of the skin side layer 25a and the low basis weight portion 25bL of the non-skin side layer 25b. As shown in FIGS. 7 and 8, in the skin side layer 25a and the non-skin side layer 25b, a plurality of low basis weight portions 25aL, 25bL are provided at intervals in the vertical direction. Note that in the present embodiment, the shapes of the low basis weight portions 25aL, 25bL are shown as substantially rhombus shapes, but the shapes, numbers, and arrangements of the low basis weight portions 25aL, 25bL are not limited to the configurations of the low basis weight portions 25aL, 25bL in the present embodiment.

[0082] FIG. 9 is a diagram showing a modified example of the sheet portion 25. In the present embodiment, as the sheet portion 25, a sheet member different from the inner layer sheet 21 and the ventral outer layer sheet 22 (dorsal outer layer sheet 32) was provided, but the present invention is not limited thereto. For example, in the modified example shown in FIG. 9, a separate sheet member is not provided as the sheet portion 25, and the upper end of the ventral outer layer sheet 22 (dorsal outer layer sheet 32) is not folded back toward the skin side. Above the absorbent body 10, the inner layer sheet 21 is located closest to the skin side.

[0083] And in this modified example, the upper end portion of the inner layer sheet 21, which is a part of the inner layer sheet 21, functions as the sheet portion 25. That is, all of the inner layer sheet 21 or at least the portion of the inner layer sheet 21 that becomes the sheet portion 25 has a skin-side layer 25a on the skin side and a non-skin-side layer 25b on the non-skin side in the thickness direction of the skin-side layer 25a. And a joining portion 50x (not shown here) in which a part of the inner layer sheet 21, that is, the sheet portion 25, is welded or adhered to the ventral outer layer sheet 22 (adjacent sheet member) adjacent to the non-skin surface side in the thickness direction of the sheet portion 25. Also in this modified example, since the hydrophilicity of the non-skin-side fibers 25bs of the non-skin-side layer 25b is lower than that of the skin-side fibers 25as of the skin-side layer 25a, even if the sheet portion 25 of the inner layer sheet 21 gets wet with sweat or the like during wearing, the adhesive strength at the joining portion 50x can be maintained without continuously retaining moisture in the non-skin-side layer 25b. Thereby, the sheet portion 25 is prevented from peeling off from the ventral outer layer sheet 22.

[0084] Figures 10A and 10B are diagrams for explaining another modification example of the sheet portion 25. In the modification example shown in Figures 10A and 10B, a separate sheet member is not provided as the sheet portion 25, and the folded-back portion 22r (32r) of the ventral outer layer sheet 22 (dorsal outer layer sheet 32) is used as the sheet portion 25 (35). In this modification example, at least the portion of the ventral outer layer sheet 22 (dorsal outer layer sheet 32) that becomes the sheet portion 25 (35) has a skin-side layer 25a on the skin side and a non-skin-side layer 25b on the non-skin side in the thickness direction of the skin-side layer 25a. And, the sheet portion 25 (35) which is a part of the ventral outer layer sheet 22 (dorsal outer layer sheet 32) and the inner layer sheet 21 (adjacent sheet member) adjacent to the sheet portion 25 (35) from the non-skin surface side in the thickness direction have a joint portion 50x (not shown here) joined by welding or adhesion. Thereby, even when the sheet portion 25 (35) which is the folded-back portion 22r (32r) gets wet with sweat or the like, since the hydrophilicity of the non-skin-side fibers 25bs of the non-skin-side layer 25b is lower than that of the skin-side fibers 25as of the skin-side layer 25a, the adhesive strength at the joint portion 50x can be maintained without continuously retaining moisture in the non-skin-side layer 25b. Thereby, it is possible to prevent the sheet portion 25 from peeling off from the inner layer sheet 21.

[0085] Figure 11 is a diagram showing a modification example of the arrangement of the sheet portion 25 (35). In the modification example shown in Figure 11, the sheet portion 25 (35) is not provided up to both left and right ends of the ventral body circumferential portion 20 (dorsal body circumferential portion 30), and is provided at the central portion in the left-right direction of the ventral body circumferential portion 20 (dorsal body circumferential portion 30) and straddling the upper end 10e of the absorbent body 10 in the vertical direction. Since the upper end 10e of the absorbent body 10 is a portion where the unevenness is relatively large, by arranging the sheet portion 25 (35) so that at least the upper end 10e is entirely covered, the friction on the skin during wearing can be suppressed and the irritation given to the skin can be reduced.

[0086] FIG. 12 is a diagram showing yet another modification of the sheet portion 25 (35). In the modification shown in FIG. 12, a sheet member that becomes the sheet portion 25 (35) is provided between the inner layer sheet 21 of the absorbent body 10. Further, the sheet member that becomes the sheet portion 25 is provided in the ventral body circumferential portion 20 in the region from one end in the left-right direction to the other end between the pair of side joining portions SS, and from the upper end to the lower end in the vertical direction of the pair of side joining portions SS. In the dorsal body circumferential portion 30, the sheet member that becomes the sheet portion 35 is provided in the region from one end in the left-right direction to the other end between the pair of side joining portions SS, and from the upper end to the vicinity of the lower end in the vertical direction of the pair of side joining portions SS. With such a configuration, the skin-side layer 25a exists in most of the skin contact surface in the region of the ventral body circumferential portion 20 (dorsal body circumferential portion 30) other than the region where the absorbent body 10 is disposed, and the skin feel is improved. Further, even if the sheet member (sheet portion 25) is disposed on most of the skin contact surface of the ventral body circumferential portion 20 (dorsal body circumferential portion 30) in this way, since the hydrophilicity of the non-skin-side fibers 25bs of the non-skin-side layer 25b is lower than that of the skin-side fibers 25as of the skin-side layer 25a, after the sheet member (sheet portion 25) is wetted with sweat or the like, the moisture is not continuously held by the non-skin-side layer 25b, and the bonding strength between the sheet member and the sheet member adjacent to the non-skin side can be maintained.

[0087] FIG. 13 is a diagram for explaining yet another modification of the arrangement of the sheet portion 25. In the modification shown in FIG. 13, the sheet portion 25 is provided as the top sheet 12 of the absorbent body 10. Since the top sheet 12 is a member that contacts the skin of the wearer in the absorbent body 10, by providing the sheet portion 25 as the top sheet 12, the skin feel can be improved by the skin-side fibers 25as of the skin-side layer 25a, and the discomfort to the skin of the wearer and the adverse effects on the skin of the wearer can be reduced.

[0088] <Regarding other aspects of the absorbent article 1> Regarding the absorbent article 1, in addition to the above-described aspects, the following aspects are also possible.

[0089] (Other aspect 1) An absorbent article 1 having a vertical direction and a thickness direction that intersect each other, comprising an absorbent body 10, a ventral body circumferential portion 20 located on the ventral side of the wearer, and a dorsal body circumferential portion 30 located on the dorsal side of the wearer. At least one of the ventral body circumferential portion 20 and the dorsal body circumferential portion 30 has a cotton layer 25a based on cotton fibers on the outermost skin side, and a sheet portion 25 is provided, at least a part of which is disposed above the absorbent body 10 in the vertical direction. When the region of the sheet portion 25 disposed above the absorbent body 10 in the vertical direction is defined as the upper disposed region, the upper disposed region and an adjacent sheet member adjacent to the non-skin side in the thickness direction of the upper disposed region are joined by welding or adhesion at a joint portion 50x, and the absorbent article 1 is characterized by having a non-joined portion 50z where the upper disposed region and the adjacent sheet member are not joined by welding or adhesion.

[0090] Then, the non-joined portion 50z of the sheet portion 25 in contact with the skin is a portion that is easily deformed freely. When movement occurs in the body circumferential portions 20 and 30, the non-joined portion 50z follows such movement to reduce friction with the skin, thereby suppressing the fluffing of cotton fibers. At the same time, by having the joint portion 50x, the shedding of cotton fibers can also be suppressed. Furthermore, by continuously contacting the skin with the cotton layer while reducing friction with the skin, the softness of cotton can be felt while suppressing irritation to the skin.

[0091] (Other Aspect 2) In the unfolded state and the stretched state, the total area of the non-joined portions 50z when the upper disposed region is viewed in plan is larger than the total area of the joined portions 50x. The absorbent article 1 is characterized by this.

[0092] Then, because the total area of the non-joined portions 50z is larger, there are more portions that can follow the movement when movement occurs around the body circumference, thereby reducing friction with the skin and suppressing the fluffing of the cotton layer 25a.

[0093] (Other Aspect 3) The absorbent article 1 is characterized in that, in the vertical direction, the total length of the joint portions 50x is longer than the total length of the non-joint portions 50z.

[0094] If this is done, providing a large number of non-joint portions 50z can suppress the fluffing of the cotton layer 25a. On the other hand, however, there is a risk that the joint between the sheet portion 25 and the adjacent sheet member will peel off. By making the total length of the joint portions 50x in the vertical direction longer than the total length of the non-joint portions 50z, it is possible to make the joint less likely to peel off.

[0095] (Other Aspect 4) The sheet portion 25 has a non-skin side layer 25b located on the non-skin side in the thickness direction of the cotton layer 25a, and the absorbent article 1 is characterized in that the thermal conductivity of the cotton fibers 25as is lower than the thermal conductivity of the non-skin side fibers 25bs, which are the base fibers of the non-skin side layer.

[0096] If this is done, since the thermal conductivity of the cotton fibers 25as that come into contact with the wearer's skin is low, even if the cotton layer 25a gets wet with sweat or the like during wearing, the cotton layer 25a is not likely to become cold immediately. Also, since the thermal conductivity of the non-skin side fibers 25bs in the non-skin side layer 25b is higher than that of the cotton fibers 25as, heat exchange is likely to be promoted. Therefore, the heat that has moved to the non-skin side layer 25b is released further to the non-skin side than the non-skin side layer 25b, making it difficult for heat to accumulate in the sheet portion 25.

[0097] (Other Aspect 5) The absorbent article 1 is characterized in that the ratio of the cotton fibers 25as in the sheet portion 25 is less than 50% by mass.

[0098] If this is done, by including the cotton fibers 25as, it is possible to experience a good texture, and at the same time, by lowering the mass ratio of the cotton fibers 25as, the fluffing of the cotton layer is suppressed.

[0099] (Other Aspect 6) It has a left - right direction orthogonal to the up - down direction and the thickness direction, and at least one of the ventral body - surrounding part 20 and the dorsal body - surrounding part 30 has an inner layer sheet 21, an outer layer sheet 22(32) arranged on the non - skin side with respect to the inner layer sheet 21, and a plurality of body - surrounding elastic members 23(33) arranged at intervals in the up - down direction between the inner layer sheet 21 and the outer layer sheet 22(32) and stretchable in the left - right direction. In the cotton layer 25a, a plurality of low basis weight parts 25aL are provided at intervals in the up - down direction, and the minimum value of the center - to - center distance in the up - down direction between adjacent low basis weight parts 25aL in the up - down direction is smaller than the minimum value of the center - to - center distance in the up - down direction between adjacent body - surrounding elastic members 23(33). The absorbent article 1 is characterized by this.

[0100] Then, by providing a plurality of low basis weight parts 25aL at small intervals in the up - down direction, the shedding of cotton fibers 25as with a short average fiber length can be more suppressed, and the irritation to the skin caused by fiber shedding can be more suppressed.

[0101] (Other aspect 7) The sheet part 25 is a sheet member arranged on the skin side with respect to the inner layer sheet 21. The absorbent article 1 is characterized by this.

[0102] Then, since the body - surrounding elastic member 23(33) is arranged between the inner layer sheet 21 and the outer layer sheet 22(32), there will be a region where interference occurs between the body - surrounding elastic member 23(33) and the sheet part 25 (sheet member) including the cotton layer 25a. Thereby, it is possible to avoid excessive stretching and contraction of the cotton layer 25a on the skin surface side, reduce the friction between the cotton layer 25a and the skin, and suppress the shedding and fuzzing of the cotton fibers 25as.

[0103] (Other aspect 8) The sheet portion 25 is disposed at a distance downward from at least one of the upper ends in the vertical direction of the ventral body circumferential portion 20 and the dorsal body circumferential portion 30. When the region from the upper end of the ventral body circumferential portion 20 or the dorsal body circumferential portion 30 where the sheet portion 25 is provided to the upper end of the sheet portion 25 in the vertical direction is defined as a non-disposed region, and the region from the upper end to the lower end of the sheet portion 25 of the ventral body circumferential portion 20 or the dorsal body circumferential portion 30 where the sheet portion 25 is provided in the vertical direction is defined as a disposed region, the portion closest to the skin surface side in the non-disposed region contains hydrophobic fibers, and the magnitude of the force required to extend the non-disposed region with a unit width in the vertical direction by a unit length in the horizontal direction is greater than the magnitude of the force required to extend the disposed region with a unit width in the vertical direction by a unit length in the horizontal direction. The absorbent article 1 is characterized by this.

[0104] Then, by including hydrophobic fibers in the portion closest to the skin surface side of the non-disposed region with strong tightening, it reduces the stickiness and reduces the discomfort given to the wearer's body. In the disposed region of the sheet portion where fluffing is likely to occur when the tightening becomes strong, by weakening the tightening force, the friction with the skin is reduced, and the fluffing of cotton fibers is suppressed.

[0105] (Other aspect 9) In the vertical direction, the length of the sheet portion 25 is characterized by being half or less of the length of the ventral body circumferential portion 20 or the dorsal body circumferential portion 30. The absorbent article 1 is characterized by this.

[0106] Then, the cotton layer 25a of the sheet portion 25 reduces the friction with the skin and suppresses fluffing by suppressing the length of the cotton layer 25a. Therefore, the good feeling of the touch of the cotton layer 25a can be felt, the irritation to the skin can be reduced, and fluffing can be prevented.

[0107] (Other aspect 10) At least one of the ventral body circumferential portion 20 and the dorsal body circumferential portion 30 has an inner layer sheet 21, an outer layer sheet 22(32) disposed on the non-skin side of the inner layer sheet 21, and a folded-back portion 22r(32r) in which the upper and lower ends of the outer layer sheet 22(32) are folded back to the skin side. In the vertical direction, the absorbent article 1 is characterized in that the length of the sheet portion 25 is longer than the length of the folded-back portion 22r(32r).

[0108] Then, by providing the sheet portion 25 longer than the vertical length of the folded-back portion 22r(32r), it becomes easier to feel the good texture of the cotton layer 25a.

[0109] (Other aspect 11) At least one of the ventral body circumferential portion 20 and the dorsal body circumferential portion 30 has an inner layer sheet 21, an outer layer sheet 22(32) disposed on the non-skin side of the inner layer sheet 21, and a folded-back portion 22r(32r) in which the upper and lower ends of the outer layer sheet 22(32) are folded back to the skin side. In the vertical direction, the absorbent article 1 is characterized in that the length of the sheet portion 25 is shorter than the length of the folded-back portion 22r(32r).

[0110] Then, by not arranging the sheet portion 25 to be excessively long in the vertical direction, the possibility of the fluffing of the cotton layer 25a is further reduced.

[0111] (Other aspect 12) The sheet portion 25 is characterized in that in at least one of the ventral body circumferential portion 20 and the dorsal body circumferential portion 30, it straddles the upper and lower ends of the absorbent main body 10 in the vertical direction in the absorbent article 1.

[0112] Then, the upper end of the absorbent main body 10 is a portion where the unevenness is relatively large, and by covering the upper end, the friction against the skin can be suppressed and the irritation to the skin can be reduced.

[0113] (Other aspect 13) The absorbent article 1 is characterized in that no hook-and-loop fastener is provided between the sheet portion 25 and the adjacent sheet member in the thickness direction.

[0114] If a hook-and-loop fastener is provided, the rigidity increases and it becomes difficult to follow the movement of the adjacent sheet member. However, by not providing such a hook-and-loop fastener, the followability is improved.

[0115] (Other aspect 14) A sheet member 25 for an absorbent article, having a skin-side layer 25a capable of contacting the wearer's skin and a non-skin-side layer 25b provided on the non-skin side of the skin-side layer 25a. The hydrophilicity of the skin-side fibers 25as, which are the base fibers of the skin-side layer 25a, is higher than the hydrophilicity of the non-skin-side fibers 25bs, which are the base fibers of the non-skin-side layer 25b. The skin-side layer 25a has a predetermined basis weight portion 25ap provided with skin-side fibers 25as of a predetermined basis weight and a low basis weight portion 25aL where the basis weight of the skin-side fibers 25as is lower than that of the predetermined basis weight portion 25ap. When viewed in the thickness direction, the sheet member 25 is characterized by having a portion where the predetermined basis weight portion 25ap overlaps with the non-skin-side layer 25b and a portion where the low basis weight portion 25aL overlaps with the non-skin-side layer 25b.

[0116] In this way, while the water absorption and the feel of the sheet member 25 are improved by the skin-side layer 25a with high hydrophilicity, the moisture absorbed by the skin-side layer 25a can be easily moved from the low basis weight portion 25aL to the non-skin side of the sheet member 25. Therefore, the possibility that the moisture absorbed by the sheet member 25 continues to contact the wearer's skin can be reduced, and the discomfort and adverse effects on the wearer's skin can be reduced.

[0117] (Other aspect 15) The sheet member 25 is characterized by having a portion where the skin-side fibers 25as and the non-skin-side fibers 25bs are intertwined.

[0118] In this way, the flexibility of the sheet member 25 can be improved, and the feel of the absorbent article 1 using the sheet member 25 can be improved.

[0119] (Other aspect 16) The sheet member 25 is characterized in that the skin-side fibers 25as are cotton fibers.

[0120] Then, since the fiber shape of the skin-side fibers 25as of the skin-side layer 25a that can contact the skin of the wearer is rounded cotton fibers, the contact with the wearer's skin is good, and the irritation to the wearer's skin during wearing can be reduced.

[0121] (Other Aspect 17) The sheet member 25 has a longitudinal direction and a lateral direction orthogonal to the thickness direction, and in the longitudinal direction, a predetermined basis weight portion 25ap and a low basis weight portion 25aL are alternately arranged, and in the lateral direction, the predetermined basis weight portion 25ap and the low basis weight portion 25aL are alternately arranged. The sheet member 25 is characterized by this.

[0122] Then, while improving the water absorption and the feel of the skin by the predetermined basis weight portion 25ap of the skin-side layer 25a, it becomes easier to move the moisture absorbed by the skin-side layer 25a from the low basis weight portion 25aL to the non-skin-side layer 25b. Therefore, the possibility that the moisture absorbed by the sheet member 25 continues to contact the skin of the wearer can be reduced, and the discomfort and adverse effects on the skin of the wearer can be reduced.

[0123] (Other Aspect 17) The sheet member 25 is characterized in that the density of the skin-side fibers 25as of the low basis weight portion 25aL is lower than the density of the skin-side fibers 25as of the predetermined basis weight portion 25ap.

[0124] Then, while improving the water absorption and the feel of the skin by the skin-side layer 25a, it becomes easier to move the moisture absorbed by the skin-side layer 25a from the low basis weight portion 25aL to the non-skin-side layer 25b. Therefore, the possibility that the moisture absorbed by the sheet member 25 continues to contact the skin of the wearer can be reduced, and the discomfort and adverse effects on the skin of the wearer can be reduced.

[0125] (Other Aspect 18) The sheet member 25 is characterized in that at least a part of the non-skin-side fibers 25bs is present on the skin-side surface of the skin-side layer 25a.

[0126] Then, since it becomes easier to move the liquid absorbed from the skin-side layer 25a to the non-skin-side layer 25b, it is possible to reduce the risk that the moisture absorbed by the sheet member 25 continues to contact the wearer's skin, and it is possible to reduce discomfort and adverse effects on the wearer's skin.

[0127] (Other Aspect 19) The sheet member 25 is characterized in that no adhesive is provided on the sheet member 25.

[0128] Then, it is possible to reduce the risk that the sheet member 25 becomes hard and reduce the risk that the absorption of moisture is hindered by the adhesive, while suppressing the irritation to the skin of the wearer of the absorbent article 1 using this sheet member 25.

[0129] (Other Aspect 20) The sheet member 25 is characterized in that no portion obtained by squeezing a part of the sheet member 25 in the thickness direction is provided on the sheet member 25.

[0130] Then, it is possible to reduce the risk that the sheet member 25 becomes hard and suppress the irritation to the skin of the wearer of the absorbent article 1 using this sheet member 25.

[0131] (Other Aspect 21) The sheet member 25 is characterized in that it has a sheet squeezing portion obtained by squeezing a part of the skin-side layer 25a in the thickness direction with the skin-side layer 25a.

[0132] Then, it is possible to reduce the risk that the skin-side layer 25a and the non-skin-side layer 25b separate.

[0133] (Other Aspect 22) The absorbent article 1 has a hydrophilic member having a higher hydrophilicity than the sheet member 25, and in the absorbent article 1, the sheet member 25 is used on the skin side in the thickness direction and at a position overlapping the hydrophilic member when viewed in the thickness direction, with respect to the hydrophilic member.

[0134] Then, when the absorbent article 1 is worn, it becomes easier to move the moisture absorbed from the sheet member 25 side to the non-skin side, so that it is possible to reduce the discomfort and adverse effects caused by the continuous adhesion of moisture to the wearer's skin.

[0135] (Other Aspect 23) The absorbent article 1 has a stretchable member, and in the absorbent article 1 in the deployed and stretched state, the sheet member 25 is used at a position overlapping at least a part of the stretchable member when viewed in the thickness direction. The sheet member 25 is characterized by this.

[0136] Then, while improving the feel of the absorbent article 1 by the sheet member 25, by forming wrinkles in at least a part of the sheet member 25, the air permeability of the sheet member 25 is improved, and the stuffiness and irritation to the skin when the absorbent article 1 is worn can be reduced.

[0137] (Other Aspect 24) The absorbent article 1 has a squeezing member having a squeezed portion in the thickness direction. In the absorbent article 1, the sheet member 25 is provided on the skin side of the squeezing member, and when viewed in the thickness direction, the portion where the low basis weight portion 25aL and the non-skin side layer 25b overlap has a portion overlapping the squeezed portion of the squeezing member. The sheet member 25 is characterized by this.

[0138] Then, since the compression member has a portion with a high density due to squeezing, it becomes easier to move moisture from the sheet member 25 to the compression member by capillary action.

[0139] (Other Aspect 25) The sheet member 25 is characterized by having a portion where the skin side fiber 25as and the non-skin side fiber 25bs are melt-bonded.

[0140] Then, it is possible to reduce the risk of separation between the skin side layer 25a and the non-skin side layer 25b.

[0141] (Other Aspect 26) The non-skin-side fiber 25bs is a thermoplastic fiber and has an adjacent member provided at a position overlapping the sheet member 25 when viewed in the thickness direction in the absorbent article 1. The absorbent article includes a welded joint portion where the sheet member 25 and the adjacent member are welded and joined in the thickness direction. When the absorbent article 1 is viewed in the thickness direction, a portion where the low basis weight portion 25aL and the non-skin-side layer 25b overlap overlaps at least a part of the welded joint portion. The sheet member 25 is characterized by this.

[0142] Then, the possibility of the bonding strength of the welded joint portion decreasing can be reduced.

[0143] (Other Aspect 27) The non-skin-side fiber 25bs is a thermoplastic fiber. The absorbent article 1 has a joint portion where both left and right sides in the lateral direction of a pair of body circumferential portions 20, 30 are welded and joined. When viewed in the thickness direction, the sheet member 25 is used at a position overlapping at least a part of the joint portion. The joint portion overlaps at least a part of a portion where the low basis weight portion 25aL and the non-skin-side layer 25b overlap. The sheet member 25 is characterized by this.

[0144] Then, the possibility of the bonding strength of the joint portion on both left and right sides in the lateral direction of the pair of body circumferential portions 20, 30 decreasing can be reduced.

[0145] (Other Aspect 28) The pair of body circumferential portions 20, 30 have a plurality of joint portions intermittently in the vertical direction. In the vertical direction, the distance between the centers of adjacent joint portions is longer than the distance between the centers of the low basis weight portions 25aL. The sheet member is characterized by this.

[0146] Then, while making it easier for the moisture absorbed by the skin-side layer 25a to move from the low basis weight portion 25aL to the non-skin-side layer 25b, the possibility of the bonding strength of the joint portion on both left and right sides in the lateral direction of the pair of body circumferential portions 20, 30 decreasing can be reduced.

[0147] (Other Aspect 29) The joint portions are provided intermittently in the vertical direction, and the sheet member 25 has a longitudinal direction and a lateral direction orthogonal to the thickness direction. The area of the region defined by a straight line connecting the centers of four low basis weight portions 25aL adjacent to each other in the longitudinal direction and the lateral direction is smaller than the maximum area of the joint portions. The sheet member 25 is characterized by this.

[0148] Then, compared with the case where the area of the region defined by a straight line connecting the centers of four low basis weight portions 25aL adjacent to each other in the longitudinal direction and the lateral direction is made larger than the maximum area of the joint portions, it becomes easier to provide a wider region where the low basis weight portions 25aL and the joint portions overlap when viewed in the thickness direction, and it becomes easier to increase the joint strength at the joint portions.

[0149] (Other Aspect 30) The joint portions are provided intermittently in the vertical direction, and the sheet member 25 has a longitudinal direction and a lateral direction orthogonal to the thickness direction. The area of the region defined by a straight line connecting the centers of four low basis weight portions 25aL adjacent to each other in the longitudinal direction and the lateral direction is larger than the minimum area of the joint portions. The sheet member 25 is characterized by this.

[0150] Then, compared with the case where the area of the region defined by a straight line connecting the centers of four low basis weight portions 25aL adjacent to each other in the longitudinal direction and the lateral direction is made larger than the maximum area of the joint portions, the region where the low basis weight portions 25aL and the joint portions overlap becomes wider when viewed in the thickness direction, so that the joint strength does not become excessively strong, and the possibility of making it difficult to separate the ventral body circumferential portion 20 and the dorsal body circumferential portion 30 after use of the absorbent article 1 can be reduced.

[0151] (Other Aspect 31) An absorbent article 1 having an absorber 10 and a sheet member 25 provided on the skin side of the absorber 10, wherein the sheet member 25 has a skin side layer 25a capable of contacting the skin of the wearer and a non-skin side layer 25b provided on the non-skin side of the skin side layer 25a, and the hydrophilicity of the skin side fibers 25as which are the base fibers of the skin side layer 25a is higher than the hydrophilicity of the non-skin side fibers 25bs which are the base fibers of the non-skin side layer 25b. The skin side layer 25a has a predetermined basis weight portion 25ap provided with skin side fibers 25as of a predetermined basis weight and a low basis weight portion 25aL having a lower basis weight of the skin side fibers 25as than the predetermined basis weight portion 25ap. When viewed in the thickness direction, the absorbent article is characterized by having a portion where the predetermined basis weight portion 25ap and the non-skin side layer 25b overlap and a portion where the low basis weight portion 25aL and the non-skin side layer 25b overlap.

[0152] Then, while improving the water absorption and the feel of the skin of the sheet member 25 by the skin side layer 25a having a high hydrophilicity, it becomes easier to move the moisture absorbed by the skin side layer 25a from the low basis weight portion 25aL to the non-skin side of the sheet member 25. Therefore, it is possible to reduce the risk that the moisture absorbed by the sheet member 25 continues to contact the skin of the wearer, and it is possible to reduce the discomfort and adverse effects on the skin of the wearer.

[0153] ===Others=== The above-described embodiments are for facilitating the understanding of the present invention and are not for limiting the interpretation of the present invention. It goes without saying that the present invention can be changed and improved without departing from the gist thereof, and equivalents thereof are included in the present invention.

[0154] In the above-described embodiments and modifications, the sheet part 25(35) was provided on both the ventral body circumferential part 20 and the dorsal body circumferential part 30, but the present invention is not limited thereto, and the sheet part 25(35) may be configured to be provided only on one of the ventral body circumferential part 20 and the dorsal body circumferential part 30.

Explanation of reference numerals

[0155] 1 Pant-type disposable diaper (absorbent article) 10 Absorbent main body, 10e Upper end 11 Absorbent core 12 Top sheet 13 Back sheet 14 Exterior sheet 15 Elastic member around the legs 18 Exterior body 20 Abdominal body circumference part 21 Inner layer sheet 22 Abdominal outer layer sheet, 22r folded part 23 Body circumference elastic member 25 Sheet part 25a Skin side layer (cotton layer) 25aL Low basis weight part 25ap Specified basis weight part 25as Cotton fiber 25b Non-skin side layer 25bA Non-skin side layer skin side part 25bB Non-skin side layer non-skin side part 25bL Low basis weight part 25bp Specified basis weight part 25bs Non-skin side fiber 30 Dorsal body circumference part 32 Dorsal outer layer sheet, 32r folded part 33 Body circumference elastic member 34 Elastic member around the hind legs 35 Sheet part 40 Lower thigh part 50x Joint part 50z Non-joint part

Claims

1. An absorbent article having an absorbent body, a ventral body circumferential portion located on the ventral side of the wearer, and a dorsal body circumferential portion located on the dorsal side of the wearer, having a sheet portion disposed on at least one of the most skin-side of the ventral body circumferential portion and the dorsal body circumferential portion, the sheet portion and an adjacent sheet member adjacent to the non-skin side of the sheet portion being joined by adhesion or welding, the sheet portion having a skin-side layer that contacts the skin of the wearer and a non-skin-side layer located on the non-skin side of the skin-side layer, the hydrophilicity of the skin-side fibers, which are the base fibers of the skin-side layer, being higher than the hydrophilicity of the non-skin-side fibers, which are the base fibers of the non-skin-side layer An absorbent article, characterized in that.

2. The absorbent article according to claim 1, the content rate of the skin-side fibers in the sheet portion being 50 mass% or less An absorbent article, characterized in that.

3. The absorbent article according to claim 1 or 2, at least a part of the skin-side fibers in the skin-side layer being present on the same surface as the non-skin-side surface of the non-skin-side layer An absorbent article, characterized in that.

4. The absorbent article according to claim 1 or 2, the average fiber length of the skin-side fibers in the skin-side layer being shorter than the average fiber length of the non-skin-side fibers in the non-skin-side layer An absorbent article, characterized in that.

5. The absorbent article according to claim 1 or 2, when, in the skin-side layer and the non-skin-side layer, a portion where the fibers are welded is defined as a welded portion, the total volume of the welded portions per unit volume of the non-skin-side layer being larger than the total volume of the welded portions per unit volume of the skin-side layer An absorbent article, characterized in that.

6. The absorbent article according to claim 5, wherein the ratio of the total volume of the welded portions in the total volume of the non-skin side layer is 5% or more and 25% or less. The absorbent article is characterized by this.

7. The absorbent article according to claim 1 or 2, wherein the non-skin side layer has, in the thickness direction of the non-skin side layer, a non-skin side layer skin side portion located on the skin side and a non-skin side layer non-skin side portion located on the non-skin side, the fiber density of the non-skin side fibers in the non-skin side layer non-skin side portion is higher than the fiber density of the non-skin side fibers in the non-skin side layer skin side portion. The absorbent article is characterized by this.

8. The absorbent article according to claim 1 or 2, wherein the non-skin side layer has, in the thickness direction of the non-skin side layer, a non-skin side layer skin side portion located on the skin side and a non-skin side layer non-skin side portion located on the non-skin side, the fiber density of the non-skin side fibers in the non-skin side layer skin side portion is higher than the fiber density of the non-skin side fibers in the non-skin side layer non-skin side portion. The absorbent article is characterized by this.

9. The absorbent article according to claim 1 or 2, wherein the non-skin side layer has, in the thickness direction of the non-skin side layer, a non-skin side layer skin side portion located on the skin side and a non-skin side layer non-skin side portion located on the non-skin side, the hydrophilicity of the non-skin side fibers in the non-skin side layer skin side portion is higher than the hydrophilicity of the non-skin side fibers in the non-skin side layer non-skin side portion. The absorbent article is characterized by this.

10. The absorbent article according to claim 1 or 2, wherein the skin side fibers are cotton fibers. The non-skin side fibers are at least hydrophobic fibers containing any one of polypropylene, polyethylene, and polyurethane, or fibers obtained by hydrophilizing any one of polypropylene, polyethylene, and polyurethane. An absorbent article, characterized in that.

11. The absorbent article according to claim 1 or 2, The skin side layer has a predetermined basis weight portion provided with the skin side fibers having a predetermined basis weight, and a low basis weight portion having a lower basis weight of the skin side fibers than the predetermined basis weight portion. An absorbent article, characterized in that.

12. The absorbent article according to claim 11, The non-skin side layer has a predetermined basis weight portion provided with the non-skin side fibers having a predetermined basis weight, and a low basis weight portion having a lower basis weight of the non-skin side fibers than the predetermined basis weight portion, The low basis weight portion of the skin side layer and the low basis weight portion of the non-skin side layer have a portion overlapping in the thickness direction of the absorbent article. An absorbent article, characterized in that.

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