Absorbent articles

Abstract

To provide an absorbent article that easily gives a wearer or the like an impression of the absorbent article having sweat absorption and transpiration functions while improving sweat absorption and water transpiration of a waist part.SOLUTION: An absorbent article (1) including a liquid-absorbent absorbent core (11) and a pair of waist parts (20) provided on a non-skin side of the absorbent core (11), has a colored part (S) that is colored. At least one waist part (40a) of the waist parts (20) has a hydrophobic part (41) that is hydrophobic and a hydrophilic part (42) that is hydrophilic. The hydrophilic part (42) is at least part of a most non-skin side surface of the one waist part (40a). When viewed from the non-skin side, the hydrophobic part (41) is overlapped with at least part of the hydrophilic part (42) and the hydrophilic part (42) is overlapped with at least part of the colored part (S).SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to absorbent articles.

Background Art

[0002] Conventionally, in absorbent articles such as disposable diapers in the form of pants, a technique of enhancing water absorption by using a hydrophilic sheet for the sheet member constituting the absorbent article is known. For example, Patent Document 1 discloses a disposable diaper provided with a waist flap having a hydrophobic skin-side sheet located on the skin side of the wearer and a hydrophilic non-skin-side sheet located on the non-skin-facing surface side of the skin-side sheet. Such a disposable diaper can easily absorb moisture such as sweat from the wearer's skin when worn.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the disposable diaper described in Patent Document 1, even if the non-skin-side sheet absorbs moisture such as sweat, it has been difficult for the wearer or the person putting on the disposable diaper to visually recognize that the disposable diaper has absorbed sweat or the like. In addition, due to the hydrophobic outer layer sheet provided on the non-skin-facing surface side of the non-skin-side sheet, the moisture absorbed from the wearer's skin or the like tends to stay in the non-skin-side sheet, and the waist flap in a state containing moisture may cause problems such as skin irritation or discomfort to the wearer's skin.

[0005] The present invention has been made in view of the above-mentioned problems, and its objective is to provide an absorbent article that improves the sweat absorption and moisture evaporation properties of the torso area, while also giving the wearer the impression that it is an absorbent article with sweat absorption and evaporation functions. [Means for solving the problem]

[0006] The main invention for achieving the above objective is: It has intersecting vertical and horizontal directions, An absorbent body equipped with a liquid-absorbing core, A pair of waist portions provided on the non-skin side of the absorbent core, An absorbent article having, Having a colored part, At least one of the aforementioned body parts has a hydrophobic portion and a hydrophilic portion, The hydrophilic portion is at least a part of the non-skin side of one of the torso sections, When viewed from the non-skin side, At least a portion of the hydrophobic portion and the hydrophilic portion overlap, At least a portion of the hydrophilic portion and the colored portion overlap, The colored portion is a sheet member provided on the skin side of the hydrophobic portion. In the aforementioned torso portion, the sheet member is provided above the absorbent core. In the aforementioned vertical direction, the lower end of the sheet member and the upper end of the absorbent core are separated by a predetermined distance. When viewed from the non-skin side, the sheet member has a portion that overlaps with the absorbent body. Yes, The lower end of the colored portion has a non-jointed portion in the thickness direction of one of the body sections that is not joined to the adjacent member. This is an absorbent article characterized by the following features. Other features of the present invention will be made clearer by description in this specification and the accompanying drawings. [Effects of the Invention]

[0007] According to the present invention, by providing a colored portion in an area overlapping with a hydrophilic portion, the absorbent article can transfer the wearer's sweat from the hydrophobic portion to the hydrophilic portion in the torso area, and evaporate the moisture in the hydrophilic portion. Since the colored portion is more likely to change color due to moisture absorption than the white portion, it becomes easier for the wearer and those who put the absorbent article on to recognize the change in the intensity of the colored portion, and by making the wearer etc. aware of the part that absorbs sweat and evaporates moisture, it becomes easier to give the impression that it is an absorbent article with sweat absorption and evaporation functions. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic perspective view of diaper 1. [Figure 2] This is a plan view of diaper 1 in its unfolded and extended state. [Figure 3] This is a schematic cross-sectional view along line AA in Figure 2. [Figure 4] This is a schematic cross-sectional view of the portion of diaper 1, folded in half at the central position CL, corresponding to line AA in Figure 2. [Figure 5] Figure 5A is a plan view of the absorbent body 10, and Figure 5B is a schematic cross-sectional view of the absorbent body 10. [Figure 6] Figure 6A is an explanatory diagram showing the components of diaper 1 disassembled in the thickness direction. Figure 6B is an explanatory diagram showing the components of diaper 1 from Figure 6A stacked in the thickness direction. [Figure 7] Figures 7A to 7C illustrate the basic principle of moisture absorption and evaporation in the rear waist area 40a of diaper 1. [Figure 8] Figure 8A illustrates the color change of the water absorption region WW in the white area W. Figure 8B illustrates the color change of the water absorption region SW in the colored area S. [Figure 9] This is an enlarged cross-sectional view of a portion of the rear girth section 40a. [Figure 10] This figure illustrates another embodiment. [Modes for carrying out the invention]

[0009] The following matters are at least clarified by the description of this specification and the attached drawings. An absorbent article having a liquid-absorbent absorbent core and a pair of waist portions provided on the non-skin side of the absorbent core, the absorbent article having a colored portion that is colored, and at least one of the waist portions having a hydrophobic hydrophobic portion and a hydrophilic hydrophilic portion, the hydrophilic portion being at least a part of the outermost non-skin side of the one waist portion, and when viewed from the non-skin side, at least a part of the hydrophobic portion and the hydrophilic portion overlap, and at least a part of the hydrophilic portion and the colored portion overlap. The absorbent article is characterized in that.

[0010] According to such an absorbent article, by providing a colored portion provided in a region overlapping with the hydrophilic portion, sweat of the wearer can be transferred from the hydrophobic portion to the hydrophilic portion in the waist portion, and moisture can be evaporated by the hydrophilic portion. The colored portion is more likely to have a significant change in color density due to moisture absorption than a white member, so it is easier for the wearer and the person wearing the absorbent article to recognize it by the change in color density of the colored portion. By making the wearer and the like recognize the part that can absorb sweat and evaporate moisture, it is easier to give the impression that it is an absorbent article having a sweat absorption and evaporation function. Further, when the hydrophilic portion is a hydrophilic non-woven fabric, it becomes easier to diffuse the moisture of the wearer's sweat in the plane direction of the hydrophilic non-woven fabric, so the region where the color density changes due to moisture becomes wider, and it becomes easier for the wearer and the like to recognize the change in color density of the colored portion.

[0011] Such an absorbent article has a vertical direction and a horizontal direction that intersect each other, and in the one waist portion, it is desirable that the colored portion is provided above the absorbent core.

[0012] According to such an absorbent article, it becomes easier for the wearer and the like to recognize that the sweat of the wearer is absorbed above the absorbent core.

[0013] In such an absorbent article, it is desirable that a liquid-impermeable leak-proof sheet is provided on the non-skin side of the absorbent core, and that in one of the waist portions, the colored portion is provided above the leak-proof sheet.

[0014] Such absorbent materials make it easier for the wearer to recognize that their sweat is being absorbed above the liquid-impermeable leak-proof sheet.

[0015] The absorbent article has an intersecting vertical and horizontal direction, and it is desirable that the upper end of the colored portion is located below the upper end of one of the waist portions.

[0016] Such absorbent materials tend to give the wearer the impression that sweat is not being absorbed at the upper part of the waist area, making it easier for the wearer to touch or grasp the upper part of the waist area.

[0017] In such an absorbent article, the hydrophobic portion and the hydrophilic portion each have fibers, and it is desirable that the fiber density of the hydrophobic portion is lower than the fiber density of the hydrophilic portion.

[0018] Such absorbent materials facilitate the transfer of moisture from hydrophobic areas to hydrophilic areas, making it easier for the wearer to change the intensity of the colored areas.

[0019] In such an absorbent article, it is desirable that the colored portion has fibers, and that the colored portion has a compressed portion that is compressed in the thickness direction of one of the waist portions.

[0020] With such absorbent materials, the compressed areas with high fiber density absorb moisture more easily due to capillary action, causing the colored areas to darken and making the sweat-absorbing function more easily recognizable to the wearer.

[0021] In such an absorbent article, it is desirable that in the compressed portion, the colored portion and adjacent members adjacent in the thickness direction are compressed in the thickness direction.

[0022] Such absorbent materials can deepen the color of the colored area while also facilitating the transfer of moisture between the colored area and the adjacent material.

[0023] In such an absorbent article, it is desirable that the color of the colored portion appears darker when the one waist portion absorbs moisture than before it absorbed moisture, and that the area that appears darker has a first colored portion that appears to be a predetermined intensity of color, and a second colored portion that appears to be lighter in color than the first colored portion.

[0024] With such absorbent materials, the difference in color intensity between the first colored portion and the second colored portion makes it easier for the wearer or others to recognize the change in color intensity of the colored portion.

[0025] In such an absorbent article, the hydrophobic portion is a hydrophobic portion on one side, the hydrophilic portion is a hydrophilic portion on one side, the colored portion is a colored portion on one side, and of the body circumference portion, the other body circumference portion has a hydrophobic portion on the other side and a hydrophilic portion on the other side, the hydrophilic portion on the other side is at least a part of the non-skin side of the other body circumference portion, the other side has a colored portion on the other side, and it is desirable that when viewed from the non-skin side of the other body circumference portion, at least a part of the hydrophobic portion on the other side and the hydrophilic portion on the other side overlap, and at least a part of the hydrophilic portion on the other side and the colored portion on the other side overlap.

[0026] With such absorbent materials, the change in color intensity of the colored portion on the other side of the torso, not just one side, makes it easier for the wearer to recognize the area that absorbs sweat and allows moisture to evaporate, thus giving the impression that the other side of the torso has sweat-absorbing and moisture-wicking functions.

[0027] Such an absorbent article has an intersecting vertical direction and a horizontal direction, It is desirable that the upper end of the colored portion on one side and the upper end of the colored portion on the other side are located at different positions.

[0028] With such absorbent articles, by providing colored sections on one side of the waist and the other side of the waist in locations suitable for sweat absorption on the wearer's body, the wearer can more easily recognize the change in color intensity due to sweat absorption between the two colored sections.

[0029] The absorbent article has an intersecting vertical direction and a horizontal direction, and has a one-side joint and a other-side joint at one end and the other end in the horizontal direction, respectively, where the one body portion and the other body portion are joined, and it is desirable that on one side in the horizontal direction, the one side end of the colored portion is provided outside the one-side joint.

[0030] With such absorbent materials, the joint where one waist section is joined to the other is a part where color changes due to sweat absorption are less likely to occur. Therefore, by comparing the color of the colored area located outside the joint on one side in the left-right direction with the colored area located inside the joint on the other side in the left-right direction, it becomes easier for the wearer to recognize the difference in the intensity of the colored area due to sweat absorption.

[0031] In such an absorbent article, it is preferable that the colored portion is located on the skin side of the hydrophilic portion.

[0032] With such absorbent materials, when the torso area absorbs sweat, in addition to the color change due to sweat in the colored area, the distance between the colored area and the material located on the skin side of the colored area becomes easier to reduce, making it easier for the wearer to notice the change in the intensity of the colored area.

[0033] In such an absorbent article, it is desirable that the brightness of the colored portion is lower than the brightness of the hydrophilic portion.

[0034] With such absorbent materials, the colored areas become more visible through the hydrophilic surface, making it easier for the wearer or others to recognize changes in the intensity of the colored areas.

[0035] The absorbent article has an intersecting vertical and horizontal direction, the absorbent core is provided on the absorbent body, the colored portion is a sheet member provided on the skin side of the hydrophobic portion, and it is desirable that the colored portion overlaps with the absorbent body when viewed from the non-skin side.

[0036] With such absorbent materials, the absorbent body is thicker than the other parts, and since the absorbent body is the part where the wearer is most likely to sweat when wearing it, the overlap between the absorbent body and the colored part makes it easier for the wearer to notice the change in the intensity of the colored part due to sweat absorption.

[0037] The absorbent article has an intersecting vertical and horizontal direction, the absorbent core is provided on the absorbent body, the colored portion is a sheet member provided on the skin side of the hydrophobic portion, and it is desirable that the lower end of the colored portion has a non-jointed portion in the thickness direction of one of the waist portions that is not joined to the colored portion and the adjacent member.

[0038] With such absorbent materials, when the colored portion comes into contact with sweat during wear, the distance between the unjointed lower edge of the colored portion and the wearer's skin tends to decrease. This makes it easier for the color intensity of the colored portion to change, allowing the wearer to recognize the portion that absorbs sweat and allows moisture to evaporate, thus giving the impression that the absorbent material has sweat-absorbing and evaporative properties.

[0039] ===Execution=== The absorbent article according to the present invention will be explained using a pant-type disposable diaper 1 (hereinafter also referred to as "diaper 1") as an example. However, the absorbent article according to the present invention also includes tape-type disposable diapers, panty-type sanitary napkins, and other absorbent articles. Furthermore, the wearer of the absorbent article may be an infant, an adult, or a living organism such as an animal.

[0040] <Composition of Diaper 1> Figure 1 is a schematic perspective view of diaper 1. In the pant-type state shown in Figure 1, diaper 1 has intersecting vertical, horizontal, and front-to-back directions, and has a waist opening BH and a pair of leg openings LH, LH. The upper side in the vertical direction corresponds to the waist opening BH side, and the lower side corresponds to the crotch side. In the front-to-back direction, the front side corresponds to the wearer's abdominal side, and the back side corresponds to the wearer's back side.

[0041] Figure 2 is a plan view of diaper 1 in its unfolded and extended state. Figure 3 is a schematic cross-sectional view along line AA in Figure 2. The "unfolded state" of diaper 1 refers to the state in which the joints (side joints 1e) between the side 30sw of the front side band member 30 and the side 40sw of the rear side band member 40 on both sides of diaper 1 are separated and opened up, allowing the entire diaper 1 to be unfolded in a planar manner. The "extended state" of diaper 1 refers to the state in which the entire diaper 1 (the entire product) is stretched without wrinkles, specifically, the state in which the dimensions of each component constituting diaper 1 (for example, the absorbent body 10 and band members 30, 40, etc., described later) are stretched until they match or are close to the dimensions of the individual components.

[0042] Furthermore, in the unfolded state shown in Figure 2, the diaper 1 has intersecting longitudinal and transverse directions. The CC line in Figure 2 is the center line in the transverse direction. The longitudinal direction is along the up-and-down direction in Figure 1 and corresponds to the longitudinal direction of the absorbent body 10. The transverse direction is along the left-and-right direction in Figure 1. Also, as shown in Figure 3, the direction in which the materials constituting the diaper 1 are layered is defined as the thickness direction. In the thickness direction, the side that comes into contact with the wearer's skin is called the skin side, and the opposite side is called the non-skin side.

[0043] Diaper 1 comprises an absorbent body 10 and band members 30 and 40 positioned on the non-skin side of the absorbent body 10. Band members 30 and 40 consist of a front band member 30 corresponding to the front of diaper 1 and a rear band member 40 corresponding to the back of diaper 1. In other words, diaper 1 is a so-called three-piece type pant diaper, comprising an absorbent body 10 that is placed over the wearer's crotch area to absorb excrement such as urine, a front band member 30 with a front waistband 30a that covers the wearer's abdominal area, and a rear band member 40 with a rear waistband 40a that covers the wearer's back. Note that the pant type diaper is not limited to the three-piece type; a two-piece type pant diaper in which the front band member 30 and the rear band member 40 are integrated may also be used.

[0044] In the unfolded state shown in Figure 2, the front band member 30 and the rear band member 40 are arranged parallel to each other with a gap in the vertical direction between them, and the absorbent body 10 is stretched between them. The longitudinal ends 10ea and 10eb of the absorbent body 10 are joined and fixed to the skin side of the nearest band members 30 and 40, respectively, and its external shape is approximately H-shaped in plan view.

[0045] Starting from the state shown in Figure 2, the absorbent body 10 is folded in half, with the vertical central position CL as the folding line, so that the front band member 30 (front waist portion 30a) and the rear band member 40 (rear waist portion 40a) face each other, as shown in Figure 4. Figure 4 is a schematic cross-sectional view of the portion of the diaper 1 corresponding to line AA in Figure 2 when it is folded in half at the central position CL. In Figure 4, for convenience, the adhesive used to join the members is omitted. In this folded state, the front waist portion 30a and the rear waist portion 40a, which face each other, are joined and connected to each other at the side portions 30sw and 40sw on both the left and right sides, forming a pair of side joint portions 1e, 1e. The side joint portions 1e are formed by known joining means such as welding or bonding. The front band member 30 and the rear band member 40 are formed in an annular shape by a pair of side joints 1e, 1e, resulting in a pant-type diaper 1 with a waist opening BH and a pair of leg openings LH, LH as shown in Figure 1. The area above the upper end of the leg opening LH in the diaper 1 is called the waist area 20 (front waist area 30a, rear waist area 40a), and the area below the upper end of the leg opening LH is also called the crotch area 50. In a pant-type disposable diaper, the area that overlaps with the pair of side joints 1e in the vertical direction is called the waist area 20.

[0046] The leg opening LH of diaper 1 is formed by the waist portion 20 and a portion of the absorbent body 10 below the side joint portion 1e in the vertical direction (including the lower end of the side joint portion 1e). Specifically, the leg opening LH is the area enclosed by the lower edge of the front band member 30, the lower edge of the rear band member 40, and the left and right side edges of the absorbent body 10.

[0047] (Absorbent body 10) Figure 5A is a plan view of the absorbent body 10, and Figure 5B is a schematic cross-sectional view of the absorbent body 10. The absorbent body 10 is made of a white material and consists of an absorbent core 11 that absorbs excretory fluid, a top sheet 12 positioned on the skin side in the thickness direction of the absorbent core 11, and a back sheet 13 positioned on the non-skin side of the absorbent core 11. However, the absorbent body 10 may also have other sheet members. For example, a second sheet (not shown) may be provided between the top sheet 12 and the absorbent core 11 in the thickness direction.

[0048] The absorbent core 11 is a component that absorbs and retains excretory fluids such as urine, and is formed from liquid-absorbing fibers such as pulp fibers mixed with a superabsorbent polymer (SAP). The absorbent core 11 may also have its outer surface covered with a liquid-permeable sheet material (core wrap sheet 11b) such as tissue paper or nonwoven fabric. The absorbent core 11 of this embodiment has a constricted portion 11c between the front and rear ends in the longitudinal direction, which is narrower in the left-right direction, and has a roughly hourglass shape in plan view as shown in Figure 5A. This constricted portion 11c is the part that is held between the wearer's legs when the diaper 1 is worn, and because the length of this portion is shorter (narrower in width) in the left-right direction, the absorbent core 11 fits more easily to the wearer's crotch. The absorbent core 11 may also be a single layer in the thickness direction, or it may be a configuration of two or more layers stacked together.

[0049] The top sheet 12 is a liquid-permeable sheet, and for example, a hydrophilic air-through nonwoven fabric or a spunbond nonwoven fabric can be used. In this embodiment, as shown in Figure 5B, it is provided so as to cover the entire skin-side surface of the absorbent core 11.

[0050] The backsheet 13 has a two-layer structure consisting of a liquid-impermeable sheet 13a and a hydrophobic outer sheet 13b placed on the non-skin side. The liquid-impermeable sheet 13a is a so-called leak-proof sheet, which prevents excrement absorbed by the absorbent core 11 from leaking to the non-skin side. For the liquid-impermeable sheet 13a, for example, a resin film is used, and for the outer sheet 13b, for example, a flexible hydrophobic nonwoven fabric is used. The liquid-impermeable sheet 13a and the outer sheet 13b are provided to cover the entire non-skin side of the absorbent core 11.

[0051] A pair of leak-proof walls 15 are provided on both sides of the absorbent body 10 in the left-right direction, along the vertical direction (the longitudinal direction of the absorbent body 10). In this embodiment, the leak-proof walls 15 are formed by the outer sheet 13b described above. Specifically, in the left-right direction (lateral direction), a part of the outer sheet 13b extends outward beyond both ends of the absorbent core 11, and is folded in multiple places toward the skin, as shown in Figure 5B, thereby forming a pair of leak-proof walls 15. A leak-proof elastic member 16, such as a rubber thread, is attached to the skin-side end (tip) of the leak-proof wall 15 in an extended state along the vertical direction (the longitudinal direction of the absorbent body 10). When the diaper 1 is worn, the leak-proof walls 15 stand up toward the wearer's skin and fit to the wearer's crotch area based on the elasticity of the leak-proof elastic member 16.

[0052] Furthermore, elastic leg members 17, such as elastic threads, are attached to both sides of the absorbent body 10 in the left-right direction, stretched along the vertical direction (the longitudinal direction of the absorbent body 10). When the diaper 1 is worn, the elasticity of the leg members 17 causes both sides of the absorbent body 10 to contract, making it easier to fit around the wearer's legs.

[0053] (Front side band member 30) The front band member 30 is also the front waist portion 30a that covers the wearer's abdominal area. As shown in Figure 3, it has a non-skin sheet 32 ​​positioned on the non-skin side in the thickness direction, a skin sheet 31 laminated adjacent to the skin side of the non-skin sheet 32, and a waist elastic member 35 provided between the skin sheet 31 and the non-skin sheet 32 ​​in the thickness direction.

[0054] Figure 6A is an explanatory diagram showing the components of diaper 1 disassembled in the thickness direction, and Figure 6B is an explanatory diagram showing the components of diaper 1 in Figure 6A stacked in the thickness direction. Note that elastic members are omitted in Figures 6A and 6B. As shown in Figures 6A and 6B, the front band member 30 has the non-skin side sheet 32, skin side sheet 31, (absorbent body 10,) skin surface sheet 36 stacked in order from the non-skin side to the skin side in the thickness direction. The front band member 30 may have a two-layer structure of skin side sheet 31 and non-skin side sheet 32, or it may have a three-layer or more structure partially, such as the part where the skin surface sheet 36 is provided, or over the entire area of ​​the front band member 30. In the front band member 30, when a sheet member is provided closer to the skin than the skin side sheet 31, or closer to the non-skin side than the non-skin side sheet 32, it is preferable that the sheet member is arranged so that only a part of the skin side sheet 31 and non-skin side sheet 32 ​​is covered.

[0055] In this embodiment, the front band member 30 has a skin-side sheet 31 and a non-skin-side sheet 32 ​​of approximately the same size, but the longitudinal length of either the skin-side sheet 31 or the non-skin-side sheet 32 ​​may be longer. For example, the non-skin-side sheet 32 ​​may have a folded portion that is folded back from the non-skin side to the skin side, and from the front side in the longitudinal direction to the back side. This folded portion covers a part (upper end) of the skin-side sheet 31, which prevents the upper edge of the skin-side sheet 31 from digging into the wearer's skin.

[0056] As shown in Figure 2, the skin-side sheet 31 and the non-skin-side sheet 32 ​​are rectangular sheet members in plan view, and are formed from, for example, white SMS nonwoven fabric. In diaper 1, the sheet member (nonwoven fabric) constituting the non-skin-side sheet 32 ​​has higher hydrophilicity than the sheet member (nonwoven fabric) constituting the skin-side sheet 31. That is, the skin-side sheet 31 is made of a nonwoven fabric with low hydrophilicity, and the skin-side sheet 31 is also called the "hydrophobic part 31". In contrast, the non-skin-side sheet 32 ​​is made of a nonwoven fabric with higher hydrophilicity than the skin-side sheet 31, and the non-skin-side sheet 32 ​​is also called the "hydrophilic part 32".

[0057] The waist elastic member 35 is an expandable and contractible member that can stretch in the left-right direction, and in this embodiment, white elastic thread is used. Multiple waist elastic members 35 are arranged vertically between the skin-side sheet 31 and the non-skin-side sheet 32, and are attached in a state that is stretched in the left-right direction. Due to the elasticity exhibited by the waist elastic member 35, the front band member 30 (front waist portion 30a) fits the wearer's abdominal waist.

[0058] The torso elastic member 35 can be attached using an adhesive such as a hot melt adhesive. For example, the torso elastic member 35 can be attached by applying a hot melt adhesive to it, stretching it to a predetermined elongation ratio, and sandwiching it between the skin-side sheet 31 and the non-skin-side sheet 32. In other words, the skin-side sheet 31 and the non-skin-side sheet 32 ​​are joined together by the adhesive via the torso elastic member 35.

[0059] Furthermore, the front band member 30 has a skin-facing sheet 36. As shown in Figure 3, the skin-facing sheet 36 is a sheet member positioned to cover the upper end (front end in the vertical direction) of the absorbent body 10 from the skin side, and functions as a cover sheet. This prevents the upper edge of the absorbent body 10 from digging into the wearer's skin when the diaper 1 is worn. The skin-facing sheet 36 is made of, for example, SMS nonwoven fabric, and in this embodiment, it is blue. In Figure 3, the skin-facing sheet 36 is provided to cover a part of the skin side of the skin-facing sheet 31. In the diaper 1, the skin-facing sheet 36 is part of the front band member 30 (front waist portion 30a), but the skin-facing sheet 36 may be a member independent of the front band member 30 and the absorbent body 10.

[0060] Furthermore, the front band member 30 is provided with multiple openings 30h. Each opening 30h is a through-hole that penetrates the front band member 30 in the thickness direction. Specifically, it is a through-hole that penetrates the skin-side sheet 31 and the non-skin-side sheet 32. In the portion where the skin-side sheet 36 is provided, it is a through-hole that penetrates the skin-side sheet 36, the skin-side sheet 31, and the non-skin-side sheet 32. Providing the openings 30h improves the breathability of the front band member 30. Also, by arranging the openings 30h so that they are visible from the non-skin side of the front band member 30, it becomes easier for the user to recall that the front band member 30 has good breathability. Each opening 30h is, for example, circular in shape with a diameter of about 1 mm, but the shape and arrangement (number and pattern) of the openings 30h can be changed as appropriate.

[0061] (Rear side band member 40) The rear band member 40 has a rear waist portion 40a that covers the back of the wearer and a buttock cover 40b that covers the wearer's buttocks. Specifically, in the vertical direction, the area that overlaps with the side joint portion 1e (side portion 40sw) is the rear waist portion 40a, and the area below the side joint portion 1e is the buttock cover 40b. The buttock cover 40b allows the rear band member 40 to widely cover the wearer's buttocks when the diaper 1 is worn. Note that the rear band member 40 does not necessarily need to have a buttock cover 40b, and may consist only of the rear waist portion 40a.

[0062] The buttock cover 40b is provided with a curved elastic member 47, such as a white elastic thread, as shown in Figure 2. The curved elastic member 47 is attached between the skin-side sheet 41 and the non-skin-side sheet 42 in an extended state. The elasticity of the curved elastic member 47 makes it easier for the buttock cover 40b of the rear band member 40 to fit the wearer's buttocks when the diaper 1 is worn, and also makes it less likely to roll up from the buttocks.

[0063] As shown in Figure 3, the device comprises a non-skin-side sheet 42 positioned on the non-skin-side in the thickness direction, a skin-side sheet 41 laminated adjacent to the skin side of the non-skin-side sheet 42, and a waist elastic member 45 provided between the skin-side sheet 41 and the non-skin-side sheet 42 in the thickness direction.

[0064] As shown in Figures 6A and 6B, the rear band member 40, like the front band member 30, has a non-skin side sheet 42, a skin side sheet 41, (absorbent body 10), and a skin side sheet 46 stacked in order from the non-skin side to the skin side in the thickness direction. The rear band member 40 may have a two-layer structure of a skin side sheet 41 and a non-skin side sheet 42, or it may have a three-layer or more structure, either partially, such as in the area where the skin side sheet 46 is provided, or throughout the entire area of ​​the rear band member 40. In the case where a sheet member is provided on the skin side of the skin side sheet 41 or on the non-skin side of the non-skin side sheet 42 in the rear band member 40, it is preferable that the sheet member is arranged so that only a part of the skin side sheet 41 and the non-skin side sheet 42 is covered.

[0065] In this embodiment, the rear band member 40 has a skin-side sheet 41 and a non-skin-side sheet 42 of approximately the same size, but the longitudinal length of either the skin-side sheet 41 or the non-skin-side sheet 42 may be longer. For example, the non-skin-side sheet 42 may have a folded portion that is folded back from the non-skin side to the skin side, and from the front side in the longitudinal direction to the rear side. This folded portion covers a part (upper end) of the skin-side sheet 41, which prevents the upper edge of the skin-side sheet 41 from digging into the wearer's skin.

[0066] As shown in Figure 2, the skin-side sheet 41 and the non-skin-side sheet 42 are rectangular sheet members in plan view, and are formed from, for example, white SMS nonwoven fabric. In diaper 1, the sheet member (nonwoven fabric) constituting the non-skin-side sheet 42 has higher hydrophilicity than the sheet member (nonwoven fabric) constituting the skin-side sheet 41. That is, the skin-side sheet 41 is made of a nonwoven fabric with low hydrophilicity, and the skin-side sheet 41 is also called the "hydrophobic part 41". In contrast, the non-skin-side sheet 42 is made of a nonwoven fabric with higher hydrophilicity than the skin-side sheet 41, and the non-skin-side sheet 42 is also called the "hydrophilic part 42". Details of the hydrophilicity of each sheet 41 and 42, and the functions based on the differences in hydrophilicity, will be explained later.

[0067] The waist elastic member 45 is an expandable and contractible member that can stretch in the left-right direction, and in this embodiment, white elastic thread is used. Multiple waist elastic members 45 are arranged vertically between the skin-side sheet 41 and the non-skin-side sheet 42, and are attached in a state that is stretched in the left-right direction. Due to the elasticity exhibited by this waist elastic member 45, the rear band member 40 (rear waist portion 40a) fits the back waist of the wearer. The waist elastic member 45 can be attached in the same way as the waist elastic member 35 of the front band member 30.

[0068] Furthermore, the rear band member 40 has a skin-facing sheet 46. As shown in Figure 3, the skin-facing sheet 46 is a sheet member positioned to cover the upper end (rear end in the vertical direction) of the absorbent body 10 from the skin side, and functions as a cover sheet. This prevents the upper edge of the absorbent body 10 from digging into the wearer's skin when the diaper 1 is worn. The skin-facing sheet 46 is made of, for example, SMS nonwoven fabric, and in this embodiment, it is blue. In Figure 3, the skin-facing sheet 46 is provided to cover a part of the skin side of the skin-facing sheet 41. In the diaper 1 of this embodiment, the skin-facing sheet 46 is part of the rear band member 40 (rear waist portion 40a), but the skin-facing sheet 46 may be a member independent of the rear band member 40 and the absorbent body 10.

[0069] Furthermore, the rear band member 40 is provided with multiple openings 40h. The openings 40h are through holes that penetrate the rear band member 40 in the thickness direction, specifically through holes that penetrate the skin-side sheet 41 and the non-skin-side sheet 42, and in the portion where the skin-side sheet 46 is provided, through holes that penetrate the skin-side sheet 46, the skin-side sheet 41, and the non-skin-side sheet 42. The provision of openings 40h improves the breathability of the rear band member 40. In addition, by arranging the openings 40h so that they are visible from the non-skin-side of the rear band member 40, it becomes easier for the user to recall that the rear band member 40 has good breathability. Each opening 40h is, for example, circular in shape with a diameter of about 1 mm, but the shape and arrangement (number and pattern) of the openings 40h can be changed as appropriate.

[0070] <Regarding the hydrophilicity of each sheet> Here, we will explain the hydrophilicity of each sheet. In diaper 1, hydrophobic nonwoven fabric is used for the skin-side sheets 31, 41 and skin-facing sheets 36, 46 that make up the waistband portion 20 (front band member 30, rear band member 40), and hydrophilic nonwoven fabric with higher hydrophilicity than hydrophobic nonwoven fabric is used for the non-skin-side sheets 32, 42. Hydrophobic nonwoven fabric is also used for the outer sheet 13b that makes up the absorbent body 10.

[0071] The hydrophilic nonwoven fabric of this embodiment is obtained by applying a predetermined oil to a hydrophobic nonwoven fabric (hydrophilic treatment) to enhance its hydrophilicity. As the oil used for the hydrophilic treatment, commercially available oils effective as antistatic agents for fibers can be used, such as anionic oils, nonionic oils, and their compound products. By adding these oils to an oil tank and oiling with an oiling roller or the like, the hydrophilicity of the hydrophobic nonwoven fabric is increased, and a hydrophilic nonwoven fabric can be obtained. However, the hydrophilic nonwoven fabric may be formed by other methods. For example, a hydrophilic nonwoven fabric may be obtained by manufacturing a nonwoven fabric using highly hydrophilic fibers.

[0072] In this embodiment, the entire nonwoven fabric constituting the non-skin-facing sheets 32 and 42 is treated to increase its overall hydrophilicity. However, it is also possible for only a portion of the non-skin-facing sheets 32 and 42 to have increased hydrophilicity. For example, by treating only a portion of the non-skin-facing sheets 32 and 42 with hydrophilic treatment, the sheet member may have portions with locally high and low hydrophilicity.

[0073] The hydrophilicity of each sheet can be evaluated by measuring the contact angle when deionized water is brought into contact with the surface of each sheet. Specifically, if the contact angle between the hydrophilic nonwoven fabric and deionized water is smaller than the contact angle between the hydrophobic nonwoven fabric and deionized water, the hydrophilicity of the hydrophilic nonwoven fabric will be higher than that of the hydrophobic nonwoven fabric. For the hydrophilic nonwoven fabrics used in this embodiment (non-skin side sheets 32, 42), it is desirable that the contact angle with deionized water be less than 90 degrees, and more preferably 50 degrees or less. On the other hand, for the hydrophobic nonwoven fabrics (skin side sheets 31, 41 and skin-facing sheets 36, 46), it is desirable that the contact angle with deionized water be 90 degrees or more, and more preferably 120 degrees or more.

[0074] The contact angle can be measured using, for example, a contact angle meter MCA-J manufactured by Kyowa Interface Science Co., Ltd., in the following manner. First, deionized water (approximately 20 picoliters) is dropped onto the surface of the fibers constituting the sheet material to be measured (the sheet to be measured), and then the contact angle is immediately measured using the contact angle meter. The measurement is performed at multiple locations (e.g., 5 or more locations) on the surface of the sheet to be measured, and the average value of these measurements is taken as the contact angle. The measurement environment temperature is set at 22°C.

[0075] Alternatively, the contact angle may be measured by taking an image of the sheet to be measured, to which deionized water has been dropped, from the cross-sectional direction of the sheet, and analyzing the captured image to measure the angle between the deionized water droplet and the sheet to be measured.

[0076] <Regarding moisture absorption and evaporation> Diaper 1, equipped with hydrophilic nonwoven fabric, has sweat absorption and evaporation functions. The mechanism by which diaper 1 absorbs moisture such as sweat from the wearer's skin and evaporates the absorbed moisture into the atmosphere will be explained using the rear waistband portion 40a, but the same applies to the front waistband portion 30a. Figures 7A to 7C illustrate the basic principles of moisture absorption and evaporation in diaper 1. Figure 7 schematically shows a cross-section of the rear waistband portion 40a, one of the components constituting diaper 1.

[0077] First, when the wearer puts on the diaper 1, the portion of the rear waistband 40a where the skin-facing sheet 46 is provided comes into contact with the wearer's skin, while the portion where the skin-facing sheet 46 is not provided comes into contact with the wearer's skin, with the skin-side sheet 41. Figures 7A to 7C show the portion of the rear waistband member 40 where the non-skin-side sheet 42, the skin-side sheet 41, and the skin-facing sheet 46 overlap, viewed from the non-skin side.

[0078] As described above, the skin-facing sheet 46 and the skin-side sheet 41 are made of hydrophobic nonwoven fabric. The skin-side sheet 41 and the skin-side sheet 46 in this embodiment are made of SMS nonwoven fabric and contain meltblown fibers, which have a finer fiber diameter compared to spunbond fibers. As a result, there are areas where the fine meltblown fibers are densely intertwined, resulting in a narrow inter-fiber distance. The higher the density of the fibers constituting the hydrophobic nonwoven fabric, the more easily capillary action occurs. Therefore, while wearing the diaper 1, capillary action occurs in the skin-side sheet 41 and the skin-side sheet 46, making it easy to absorb moisture such as sweat from the wearer's skin.

[0079] Next, the moisture absorbed by the skin-side sheet 41 or skin-surface sheet 46 is transferred to the non-skin-side sheet 42 (hydrophilic nonwoven fabric) which is laminated adjacent to the non-skin side of the skin-side sheet 41, as shown in Figure 7B. As shown in Figure 7B, in the portion equipped with the skin-surface sheet 46, the moisture absorbed by the skin-surface sheet 46 is transferred to the non-skin-side sheet 42 via the skin-side sheet 41. This is because, while the skin-side sheet 41 and skin-surface sheet 46 are hydrophobic nonwoven fabrics, the non-skin-side sheet 42 is a hydrophilic nonwoven fabric. As a result, a difference in the degree of hydrophilicity (hydrophilic gradient) is created between the hydrophobic sheet and the hydrophilic sheet, making it easier for moisture to move from the less hydrophilic skin-side sheet 41 and skin-surface sheet 46 to the more hydrophilic non-skin-side sheet 42. Therefore, moisture is less likely to be retained on the skin-side sheet 41 side, which is in contact with the wearer's skin, and more likely to be retained on the non-skin-side sheet 42 side, which is not in contact with the wearer's skin.

[0080] Moisture retained in the non-skin side sheet 42 evaporates into the atmosphere from the non-skin side of the non-skin side sheet 42. As shown in Figure 7C, when the non-skin side sheet 42 is part of the material that constitutes the most non-skin side of the rear waist portion 40a, the entire non-skin side surface of the non-skin side sheet 42 is exposed to the atmosphere, increasing the surface area of ​​the interface between the non-skin side sheet 42 and the atmosphere, making it easier for moisture to evaporate.

[0081] Furthermore, the skin-facing sheet 41, which is the hydrophobic part, and the non-skin-facing sheet 42, which is the hydrophilic part, each have fibers, and it is preferable that the fiber density of the skin-facing sheet 41 is lower than the fiber density of the non-skin-facing sheet 42. In this embodiment, the fiber density of the skin-facing sheet 41 of the diaper 1 is 15 g / m². 2 The density of the lines on the non-skin side of the sheet is 18 g / m². 2 In this way, by making the fiber density of the hydrophobic portion (skin-side sheet 41), which is located closer to the skin than the hydrophilic portion (non-skin-side sheet 42) that constitutes the most non-skin side of diaper 1, it becomes easier to promote the transfer of moisture from the hydrophobic portion to the hydrophilic portion. In diaper 1, the fiber density of the skin-side sheet 46, which is located closer to the skin than the skin-side sheet 41, is lower than the fiber density of the non-skin-side sheet 42. Specifically, the fiber density of the skin-side sheet 46 is 15 g / m². 2 This facilitates the transfer of moisture from the wearer's sweat from the skin-facing sheet 46 and the skin-side sheet 41 to the non-skin-side sheet 42.

[0082] In this way, the waist portion 20 of the diaper 1 transfers moisture absorbed from the wearer's skin by the hydrophobic nonwoven fabric to the hydrophilic nonwoven fabric on the non-skin side, and releases it into the atmosphere from the non-skin surface of the hydrophilic nonwoven fabric. In other words, moisture can be absorbed and efficiently evaporated into the atmosphere. As a result, moisture is less likely to come into contact with the wearer's skin, which can prevent the wearer's skin from becoming damp and causing skin problems such as rashes, and can also prevent the wearer from feeling uncomfortable.

[0083] In the rear waist portion 40a, in the area that overlaps with the pair of side joints 1e in the vertical direction, at least a portion of the non-skin side is a hydrophilic area where a hydrophilic nonwoven fabric is arranged. In the diaper 1 of this embodiment, the non-skin side of the rear waist portion 40a is composed of a hydrophilic non-skin side sheet 42 throughout its entire area, so the entire non-skin side of the rear waist portion 40a is a hydrophilic area. Furthermore, a skin side sheet 41, which acts as a hydrophobic area, is laminated adjacent to the skin side of the hydrophilic non-skin side sheet 42. In addition, the rear waist portion 40a is provided with a portion where a skin surface sheet 46 is laminated on the skin side of the skin side sheet 41, and adjacent to the skin side sheet 41. Therefore, the hydrophobic skin-facing sheet 46 and skin-side sheet 41 absorb moisture such as sweat from the wearer's skin, and the hydrophilic gradient facilitates the movement of moisture to the non-skin-side sheet 42. The moisture that has moved from the skin side and reached the non-skin-side sheet 42 is structured to easily evaporate from the hydrophilic non-skin-side sheet 42 at the outermost non-skin surface.

[0084] <Regarding the colored part S> Diaper 1 has a colored part S. "Colored" refers to any color other than colorless, transparent, or white. White includes, for example, the color represented as "N9.5" in the Munsell color system or "255,255,255" in the RGB color space (so-called pure white), as well as colors whose color difference from pure white is less than 12. For measuring the color difference of white, for example, a Konica Minolta CR-300 can be used as a color difference meter, and a C light source (International Commission on Illumination (CIE) standard) can be used as the light source of the measuring instrument. In this case, the diameter of the measurement window of the measuring instrument is 40 mm. The color difference is ΔL, Δa, and Δb in the (L*a*b*) color space relative to a white reference plate. The color difference relative to the white reference plate can be calculated by measuring the lab value of the white reference plate and the lab value of the target sample, respectively. The white reference plate is set to lab0 at (X93.19, Y95.20, Z112.28). Here, L is a value that indicates brightness, and a and b are the planar coordinates of chromaticity. If the Lab values ​​of the white reference plate are L0, a0, and b0, and the Lab values ​​of the target sample are L1, a1, and b1, then ΔL can be calculated as ΔL=L0-L1, Δa=a0-a1, and Δb=b0-b1.

[0085] In this embodiment, the colored portion S of the diaper 1 is the skin-facing sheet 36 of the front waist portion 30a and the skin-facing sheet 46 of the rear waist portion 40a. The skin-facing sheets 36 and 46 are each blue sheet materials. The skin-facing sheets 36 and 46 may be made by coloring white nonwoven fabric after molding, or by molding blue fibers into a nonwoven fabric. Furthermore, the skin-facing sheets 36 and 46 are materials that exhibit blue color throughout, but are not limited to this. The colored portion S may be a part of the skin-facing sheets 36 and 46 that is colored.

[0086] <Regarding the color change of the colored part S> Conventionally, absorbent materials such as white disposable diapers are widely known. Figure 8A is a diagram illustrating the color change of the moisture-absorbing region WW in the white area W. Figure 8A shows the state in which a predetermined amount of water is dropped onto the white area W of a typical white disposable diaper, using the sheet material that makes up the waist area as a white sample, to form a moisture-absorbing region WW. Comparing the colors of the white area W that has not absorbed water and the moisture-absorbing region WW of the white sample, as shown in Figure 8A, the color of the moisture-absorbing region WW is only slightly lighter than the white of the white area W that has not absorbed water, and the color change between the white area W that has not absorbed water and the moisture-absorbing region WW appears to be minimal. When a white sheet material gets wet, water enters the gaps between the fibers that make up the sheet material, reducing the unevenness of the surface of the sheet material and making it less likely for diffuse reflection of light to occur on the surface of the sheet material. Furthermore, the moisture-absorbing region WW allows light to pass through the sheet material more easily, and due to the diffuse reflection of light, it appears lighter and more transparent than the white area W of the unabsorbed moisture-free region, which is visible as white. Therefore, even if an absorbent item has the sweat-absorbing function described above, it is difficult to recognize from the outside that the absorbent item is absorbing sweat. In particular, when the wearer of the absorbent item is an infant or a patient who has difficulty communicating, it is difficult for the wearer to recognize that the absorbent item is absorbing sweat or to communicate its effect to those around them. Therefore, even if a white absorbent item has a sweat-absorbing function, the color change before and after sweat absorption is minimal, making it difficult to make the wearer or those who intend to have the wearer wear the absorbent item (hereinafter also referred to as "wearer, etc.") recognize the sweat-absorbing function of the absorbent item.

[0087] In contrast, diaper 1, by having a colored portion S, makes it easier for those around to recognize the absorption of sweat by the change in the intensity of the color of the colored portion S. Figure 8B is a diagram illustrating the color change of the moisture absorption region SW of the colored portion S. Figure 8B shows the state in which the blue skin-facing sheet 46 in this embodiment is used as a colored sample of the colored portion S, and a predetermined amount of water is dropped onto the colored portion S of the colored sample to form the moisture absorption region SW. As shown in Figure 8B, when comparing the color of the unabsorbed colored portion S of the colored sample with the moisture absorption region SW, the color of the moisture absorption region SW appears clearly darker than the color of the unabsorbed colored portion S, as shown in Figure 8B. Similar to the white sheet material, when the colored sheet material gets wet, water enters the gaps between the fibers that make up the sheet material, reducing the unevenness on the surface of the sheet material and making it less likely for diffuse reflection of light to occur on the surface of the sheet material. In this case, unlike the white sheet material, the colored sheet material, due to its color, does not allow light to pass through it as easily as the white sheet material. As a result, the amount of diffusely reflected and transmitted light decreases, and the amount of specularly reflected light increases, making the color of the moisture-absorbing area SW appear darker than the color of the unabsorbed colored area S. In other words, the colored area S in diaper 1 appears darker in color after absorbing moisture than before absorption.

[0088] As described above, the rear waist portion 40a of diaper 1 has a skin-side sheet 41 as a hydrophobic portion and a non-skin-side sheet 42 as a hydrophilic portion, and the non-skin-side sheet 42 is at least a part of the most non-skin side of the rear waist portion 40a. In other words, the non-skin-side sheet 42 is a material that constitutes at least a part of the most non-skin side. It also has a blue (colored) skin-side sheet 46 that constitutes the colored portion S on the rear (one side). When diaper 1 shown in Figure 1 is viewed from the non-skin side, at least a part of the skin-side sheet 41 and the non-skin-side sheet 42 overlap, and at least a part of the non-skin-side sheet 42 and the skin-side sheet 46 overlap. In this embodiment, as shown in Figure 4, when diaper 1 is viewed along the front-to-back direction, the skin-side sheet 41 and the non-skin-side sheet 42 are the same size and overlap over almost the entire area, and the skin-side sheet 41, the non-skin-side sheet 42 and the skin-side sheet 46 also overlap. Furthermore, when the diaper 1, which has absorbed the wearer's sweat, is viewed from the non-skin side, the color of the skin-facing sheet 46 (colored part S) is visible.

[0089] As described above, the rear waist portion 40a of diaper 1 can retain and evaporate moisture with the hydrophilic non-skin sheet 42. When viewed from the non-skin side of diaper 1, a blue skin-facing sheet 46, which is a colored portion S, is provided in a position that overlaps with the non-skin sheet 42, so that the color of the colored skin-facing sheet 46 appears to darken due to sweat absorption. When a wearer or others see the color of this skin-facing sheet 46, they can recognize that, when viewed from the non-skin side of diaper 1, at least the portion of the skin-facing sheet 46 (colored portion S) that overlaps with the non-skin sheet 42 is a part that can absorb the wearer's sweat and release that moisture. Therefore, even in cases where the wearer, such as infants, cannot express how comfortable the diaper 1 is to the outside, people around the wearer, such as those putting the diaper 1 on the wearer, can see the intensity of the colored part S from the outside. This gives the impression that the colored part S (skin-facing sheet 46) of the diaper 1 is the part that absorbs the wearer's sweat, and that the darker-colored area has the function of retaining and releasing moisture from sweat. In addition, since the wearer can visually recognize that the wearer is sweating, it becomes possible to recognize from the color of the colored part S that infants and other wearers who have difficulty speaking are feeling hot. Furthermore, by making the non-skin-facing sheet 42, which is a hydrophilic nonwoven fabric, the diaper 1 makes it easier to diffuse the moisture from the wearer's sweat in the planar direction within the non-skin-facing sheet 42, and a wider area can be made into an area where the intensity of the color changes due to moisture, making it easier for the wearer to recognize the change in the intensity of the color of the skin-facing sheet 46. Furthermore, by providing a skin-facing sheet 46 as a colored part S on the back (rear) side, where sweating is more likely, it becomes easier for the wearer to notice the change in the color intensity of the skin-facing sheet 46 due to sweat absorption.

[0090] In this embodiment, the colored part S is blue, but the color of the colored part S is not limited to blue; it can be set to any color as long as it is colored. However, in order to visualize the function of absorbing moisture such as sweat, it is preferable to make the color of the colored part S a cool color such as blue or light blue. By making the color of the colored part S a cool color, it becomes easier for the wearer to associate it with water or coolness. Furthermore, it is even more preferable that the wearer can see the color of the colored part S before and after the rear waist area 40a absorbs sweat. If the wearer can recognize the part that has a sweat-absorbing function even before it absorbs sweat, they can know in advance that the diaper 1 has a sweat-absorbing function.

[0091] The front waist portion 30a of diaper 1, like the rear waist portion 40a, has a skin-side sheet 31 as a hydrophobic portion and a non-skin-side sheet 32 ​​as a hydrophilic portion, with the non-skin-side sheet 32 ​​being at least a part of the most non-skin side of the front waist portion 30a. It also has a blue (colored) skin-side sheet 36 that constitutes the colored portion S on the front (other side). When diaper 1 shown in Figure 1 is viewed from the non-skin side, at least a part of the skin-side sheet 31 and the non-skin-side sheet 32 ​​overlap, and at least a part of the non-skin-side sheet 32 ​​and the skin-side sheet 36 overlap. In this embodiment, as shown in Figure 4, when diaper 1 is viewed along the front-to-back direction, the skin-side sheet 31 and the non-skin-side sheet 32 ​​are the same size and overlap almost entirely, and the skin-side sheet 31, the non-skin-side sheet 32, and the skin-side sheet 36 also overlap. Furthermore, when the diaper 1, which has absorbed the wearer's sweat, is viewed from the non-skin side, the color of the skin-facing sheet 36 (colored part) is visible.

[0092] In this way, by providing a skin-facing sheet 36 as a colored portion S in the front waist portion 30a, not just the rear waist portion 40a, in a position that overlaps with the non-skin-facing sheet 32, it is easy for the wearer to recognize that it is a disposable diaper with a sweat-absorbing function, and that the area where the skin-facing sheet 36 is provided is a part that has the function of absorbing and evaporating moisture from sweat.

[0093] Furthermore, it is preferable that the upper end of the rear skin-facing sheet 46 (colored portion S) and the upper end of the front skin-facing sheet 36 (colored portion S) are located at different positions in the front-to-back direction. In this embodiment, as shown in Figure 4, the upper end of the rear skin-facing sheet 46 of the diaper 1 is located above the upper end of the front skin-facing sheet 36. By positioning the colored portions S according to the wearer's body shape and posture in this way, sweat can be absorbed effectively, and the change in the intensity of the color of the colored portions S due to sweat absorption can be easily recognized by the wearer. In addition, because the positions of the colored portions S are different in the front and back, it is easier for the wearer to recognize the front and back of the diaper 1.

[0094] The front waistband portion 30a of diaper 1 has the same configuration as the rear waistband portion 40a, so the following explanation will mainly focus on the rear waistband portion 40a, but the front waistband portion 30a is similar.

[0095] Furthermore, it is preferable that the colored portion S is provided above the absorbent core 11 in the rear waist portion 40a. As shown in Figure 4, etc., in the rear in the front-to-back direction, the blue skin-facing sheet 46 of the rear waist portion 40a is provided above the absorbent core 11. Since the absorbent core 11 is a material that absorbs liquid (excrement), it absorbs not only excrement such as urine, but also sweat. In contrast, by providing the skin-facing sheet 46 as a colored material S above the absorbent core 11, the change in the intensity of the color of the skin-facing sheet 46 due to sweat absorption makes it easier for the wearer to see the part of the diaper 1 that is absorbing the wearer's sweat in the area above the absorbent core 11. This gives the impression that the area that appears darker in color is absorbing the wearer's sweat and allowing the absorbed sweat moisture to evaporate. Note that in the diaper 1, the entire skin-facing sheet 46 is provided above the absorbent core 11, but this is not the only option. It is sufficient that at least a portion of the colored portion S is provided above the absorbent core 11, and in the vertical direction, a portion of the absorbent core 11 and the colored portion S (skin-facing sheet 46) may overlap.

[0096] Furthermore, it is preferable that the colored portion S is located above the liquid-impermeable sheet 13a in the rear waist portion 40a. As shown in Figure 4, etc., in the rear in the front-to-back direction, the blue skin-facing sheet 46 of the rear waist portion 40a is located above the liquid-impermeable sheet 13a. This makes it easier to see the portion above the liquid-impermeable sheet 13a that is absorbing the wearer's sweat, giving the impression that the darker-colored area is absorbing the wearer's sweat and allowing the absorbed sweat's moisture to evaporate.

[0097] Furthermore, it is preferable that the upper end of the colored portion S is located below the upper end of the rear waist portion 40a. As shown in Figure 1, the upper end of the skin-facing sheet 46 of the diaper 1 is located below the upper end of the rear waist portion 40a (rear band member 40). As a result, when the rear waist portion 40a absorbs the wearer's sweat, the upper end of the rear waist portion 40a will be a different color or shade from the skin-facing sheet 46. This makes it easier for the wearer to get the impression that the upper end of the rear waist portion 40a is not absorbing the wearer's sweat, and makes it easier for the wearer to touch or grasp the upper end of the rear waist portion 40a.

[0098] As in diaper 1, it is preferable that the colored portion S is located on the skin side of the non-skin side sheet 42, which is the hydrophilic portion. In diaper 1, the skin-facing sheet 46 has a blue colored portion S on the skin side of the non-skin side sheet 42. When the rear waist portion 40a absorbs sweat, the color of the skin-facing sheet 46 (colored portion) appears darker. Also, because the moisture from the sweat makes it easier for the skin-facing sheet 46 to reduce the distance between it and adjacent members in the thickness direction, the color of the skin-facing sheet 46 becomes darker, making it easier for the wearer to recognize that diaper 1 has absorbed the wearer's sweat.

[0099] Furthermore, if the colored portion S is located on the skin side of the hydrophilic portion (non-skin side sheet 42), it is preferable that the brightness of the colored portion S is lower than that of the hydrophilic portion. In other words, it is preferable that the brightness of the skin-facing sheet 46 is lower than that of the non-skin side sheet 42. As shown in Figure 6A, in this embodiment, the brightness of the blue skin-facing sheet 46 of the diaper 1 is lower than that of the white non-skin side sheet 42. This makes it easier to see the color of the skin-facing sheet 46 through the non-skin side sheet 42, so that the wearer can easily recognize the sweat absorption of the diaper 1 by the change in the intensity of the color of the skin-facing sheet 46.

[0100] The brightness (L value) of each sheet can be measured, for example, using a commercially available colorimeter (Konica Minolta, Inc., Colorimeter CR-300) on a white calibration plate (Konica Minolta, Inc., CR-A43 (L value 96.7)). The higher the measured brightness (L value), the brighter the sheet will appear. It is also preferable to cut out multiple samples of a predetermined size from each sheet and compare the average values ​​of the measured L values.

[0101] It is preferable that the light transmittance of the non-skin side sheet 42, which constitutes at least a portion of the most non-skin side of the rear waist portion 40a, is 50% or more. When the colored portion S is provided on the skin side of the non-skin side sheet 42, as in diaper 1, the wearer can more easily see the color of the colored portion S through the non-skin side sheet 42.

[0102] The absorbent body 10 is a portion where multiple components are layered, and is thicker than the front band member 30 and the rear band member 40. Therefore, the area where the absorbent body 10 is provided is the area where the wearer is most likely to sweat when wearing the diaper. As shown in Figure 4, it is preferable that when the diaper 1 is viewed from the non-skin side, the skin-facing sheet 46 of the colored portion S has a portion that overlaps with the absorbent body 10. The overlap between the absorbent body 10 and the skin-facing sheet 46 makes it easier for the wearer to notice the change in the color intensity of the skin-facing sheet 46 due to increased sweat absorption.

[0103] Furthermore, as shown in Figure 3, it is preferable that in the thickness direction of the rear waist portion 40a, the lower end of the skin-facing sheet 46 has a lower non-joint portion 46nd that is not joined to the skin-facing sheet 46 of the adjacent absorbent body 10. Specifically, since no adhesive is applied to the lower non-joint portion 46nd of the skin-facing sheet 46, the lower non-joint portion 46nd is a portion that is not fixed to the absorbent body 10. By providing the lower non-joint portion 46nd, when the skin-facing sheet 46 absorbs moisture, the unfixed lower non-joint portion 46nd of the skin-facing sheet 46 tends to get closer to the wearer's skin. As the distance between the wearer's skin and the lower non-joint portion 46nd decreases, the skin-facing sheet 46 absorbs more of the wearer's sweat, causing the color of the skin-facing sheet 46 to appear more intense. This makes it easier for the wearer to see the area around the back of the torso 40a that is absorbing the wearer's sweat, giving the impression that the darker-colored area is absorbing the wearer's sweat and allowing the absorbed moisture to evaporate.

[0104] Furthermore, it is preferable that on one side of the diaper 1 in the left-right direction, one side edge of the colored portion S is located outside the side joint 1e on that side. In this embodiment, as shown in Figure 1, one side edge of the skin-facing sheet 46, which is the colored portion S, is located outside the side joint 1e on that side. Specifically, the skin-facing sheet 46 is continuous from one side edge to the other side edge in the left-right direction of the diaper 1, and the skin-facing sheet 46, together with the skin-side sheet 41 and the non-skin-side sheet 42, is joined at the front waist portion 30a and the side joint 1e on one side and the side joint 1e on the other side. Of the skin-facing sheet 46, the side joints 1e and the portion outside of 1e in the left-right direction do not come into direct contact with the wearer's skin, so even if the rear waist portion 40a absorbs sweat, the color of the skin-facing sheet 46 often does not appear to change. Therefore, by comparing the color of the outer area of ​​the skin-facing sheet 46 in the left-right direction from one side joint 1e with the color of the inner area in the left-right direction from one side joint 1e, the wearer can more easily recognize the difference in color appearance caused by sweat absorption.

[0105] When the rear waist portion 40a absorbs moisture, the colored portion S appears darker than before it absorbed moisture. Preferably, the area that appears darker has a first colored portion S1 that appears to be a predetermined intensity and a second colored portion that appears lighter than the first colored portion S1. Figure 9 is an enlarged cross-sectional view of a part of the rear waist portion 40a. For example, the diaper 1 has a plurality of waist elastic members 45 between the skin-side sheet 41 and the non-skin-side sheet 42, and as these waist elastic members 45 expand and contract in the left-right direction, wrinkles that are uneven in the thickness direction are formed in the rear waist portion 40a. As shown in Figure 9, when the wrinkled rear waist portion 40a is viewed from the non-skin side, the part closest to the skin is seen as the first colored portion S1 with a predetermined intensity of color. On the other hand, the part closer to the skin than the first colored portion S1 is seen as the second colored portion S2 with a lighter color than the first colored portion S1. In this way, the difference in color intensity between the first colored portion S1 and the second colored portion S2 makes it easier for the wearer or others to recognize the color of the colored portion S.

[0106] As described above, the rear waist portion 40a (rear band member 40) has a plurality of openings 40h that penetrate in the thickness direction. When viewed from the non-skin side of the rear waist portion 40a, it is preferable that the openings 40h overlap with the colored portion S (skin-facing sheet 46). By overlapping with the openings 40h, the rear waist portion 40a absorbs moisture from sweat, making the color of the colored portion S appear darker, and thus making the uncolored openings 40h more noticeable. This makes it easier for the wearer to see the openings 40h and recognize the good breathability of the diaper 1.

[0107] ===Other Examples=== The embodiments of the present invention have been described above, but these embodiments are intended to facilitate understanding of the present invention and are not intended to limit its interpretation. Furthermore, the present invention can be modified or improved without departing from its spirit, and it goes without saying that the present invention includes equivalents thereof.

[0108] In the above embodiment, colored sections S (blue skin-facing sheets 36 and 46) were provided on the front waist section 30a and the rear waist section 40a, respectively, but the embodiment is not limited to this. The colored section S may be provided only on the front waist section 30a, or only on the rear waist section 40a. Furthermore, the entire area of ​​the front waist section 30a and the entire area of ​​the rear waist section 40a may be made into a colored section S. In addition, the configuration does not have to be such that the front waist section 30a and the rear waist section 40a each have only one colored section S. For example, for the rear waist section 40a, the colored section S may not be provided in the center in the left-right direction, but a pair of colored sections S may be provided on both ends outside the center in the left-right direction. A portion of each member (skin-facing sheet 36 and 46) may be made into a colored section S, and the portion of that member (skin-facing sheet 36 and 46) other than the colored section S may be white. The shape, size, and placement of the colored parts S can be adjusted as needed depending on the wearer's body type, constitution, posture, etc.

[0109] In the above embodiment, the skin-facing sheets 36 and 46, made of colored nonwoven fabric and located further inward from the skin-facing sheets 31 and 41 (which are hydrophobic parts) that are located on the skin-facing side of the non-skin-facing sheets 32 and 42 (which are hydrophilic parts), are designated as the colored parts S. However, the embodiment is not limited to this. Parts or all of each of the hydrophobic skin-facing sheets 31 and 41, the hydrophilic non-skin-facing sheets 32 and 42, and the waist elastic members 35 and 45 may be designated as the colored parts S, and the members of the front waist portion 30a and the rear waist portion 40a may be joined with a colored adhesive. If a colored adhesive is used, the adhesive becomes the colored parts S. Furthermore, multiple members may be colored to form the colored parts S. Note that if the skin-facing sheets 36 and 46 are not designated as colored parts, the skin-facing sheets 36 and 46 do not necessarily have to be provided.

[0110] For example, when diaper 1 is viewed from the non-skin side, the multiple waist elastic members 45 that overlap with the non-skin sheet 42 may be made into light blue colored parts S, and the non-skin sheet 42 may be made into a white sheet material. In this case, while maintaining the elastic function of the waist elastic members 45, when the waist elastic members 45 and the non-skin sheet 42 come into close contact due to the moisture of sweat, the non-skin sheet 42 in the part that overlaps with the colored waist elastic members 45 will transmit less light, making the waist elastic members 45 appear darker. Also, since the waist elastic members 45 are intermittently arranged in the vertical direction, it is easy to perceive the difference in color between the parts where the waist elastic members 45 are placed and the parts where they are not. Therefore, the wearer can visually perceive the change in the color intensity of the waist elastic members 45 through the non-skin sheet 42, making it easier to see the parts of diaper 1 that are absorbing the wearer's sweat. This gives the impression that the darker-colored areas are absorbing the wearer's sweat and allowing the absorbed sweat moisture to evaporate.

[0111] Furthermore, for example, the adhesive used to join the non-skin side sheet 42 and the skin side sheet 41 may be blue, and when the diaper 1 is viewed from the non-skin side, the blue adhesive may be provided as a colored area S in the position where it overlaps with the non-skin side sheet 42. In this case, while maintaining the adhesive function between the non-skin side sheet 42 and the skin side sheet 41, when the skin side sheet 41 and the non-skin side sheet 42 come into close contact due to the moisture from sweat, the portion overlapping with the adhesive provided between the skin side sheet 41 and the non-skin side sheet 42 will have reduced light transmission, and the color of the colored adhesive will appear darker. Also, since the adhesive can be placed in any shape and location, it becomes easier to recognize the difference in color between the part where the adhesive is provided and the part where it is not. Therefore, the wearer can visually perceive the change in the intensity of the adhesive's color through the non-skin side sheet 42, making it easier to see the part of the diaper 1 that is absorbing the wearer's sweat. This gives the impression that the darker-colored area is absorbing the wearer's sweat and allowing the absorbed sweat's moisture to evaporate.

[0112] In the above embodiment, the entire area of ​​the skin-facing sheets 36 and 46, which are the colored portion S, overlaps with the hydrophilic non-skin-facing sheets 32 and 42 and the hydrophobic skin-facing sheets 31 and 41 when viewed from the non-skin side of the diaper 1, but it is not limited to this. It is sufficient that at least a part of the colored portion S overlaps with the hydrophilic portion, so it is sufficient that at least a part of the skin-facing sheets 36 and 46 overlaps with the non-skin-facing sheets 32 and 42, and the skin-facing sheets 36 and 46 do not need to overlap with the skin-facing sheets 31 and 41. As described above, the hydrophilic non-skin-facing sheet 32 ​​has the function of retaining and evaporating moisture from sweat. Therefore, the moisture absorbed by the hydrophilic non-skin side sheet 32 ​​is diffused planarly within the non-skin side sheet 32. As a result, even if at least a portion of the skin side sheets 36 and 46 overlap when viewed from the non-skin side of the diaper 1, the overlapping area when viewed from the non-skin side has the function of absorbing and evaporating sweat moisture. The change in the intensity of the skin side sheets 36 and 46 makes it easier to see the part of the diaper 1 that has absorbed the wearer's sweat, giving the impression that the darker-colored area absorbs the wearer's sweat and allows the absorbed sweat moisture to evaporate.

[0113] The colored portion S may have fibers like the skin-facing sheet 46, and the colored portion S may also have a compressed portion (not shown) that is compressed in the thickness direction of the rear waist portion 40a. Because the fiber density of the compressed portion is higher, the compressed portion becomes a part that absorbs moisture more easily due to capillary action. When the rear waist portion 40a absorbs moisture, the compressed portion of the colored portion S absorbs more moisture, making the color appear darker. This makes it easier for the wearer to see the part of the diaper 1 that is absorbing the wearer's sweat, giving the impression that the darker-colored area is absorbing the wearer's sweat and allowing the absorbed sweat to evaporate.

[0114] Furthermore, the compressed portion of the colored portion S may be configured to be compressed in the thickness direction together with adjacent members adjacent to the colored portion S in the thickness direction. In other words, the diaper 1 may have a compressed portion in which the skin-facing sheet 46 and the skin-side sheet 41 are compressed. In the compressed portion, the fibers of adjacent sheets in the thickness direction become entangled or melted by the compression, bringing the distance between the sheets closer. This not only makes the color of the colored portion S appear darker, but also facilitates the transfer of moisture between the skin-facing sheet 46 and the skin-side sheet 41 of the colored portion S. For example, a compressed portion (welded portion) may be provided in which the skin-facing sheet 46, the skin-side sheet 41, and the non-skin-side sheet 42 are compressed (welded) in the thickness direction, and the waist elastic member 45 provided between the skin-side sheet 41 and the non-skin-side sheet 42 may be attached to the rear waist portion 40 using multiple compressed portions (welded portions).

[0115] In the above-described embodiment, openings 30h and 40h are provided that penetrate the strip members 30 and 40 in the thickness direction, respectively, but the embodiment is not limited to this. The strip members 30 and 40 may be configured without openings, or each strip member 30 and 40 may be configured with openings that penetrate only the non-skin side sheets 32 and 42, while the skin side sheets 31 and 41 do not have openings.

[0116] In the embodiments described above, so-called pant-type disposable diapers were explained, but the invention is not limited to these. For example, so-called tape-type disposable diapers 2 (hereinafter also referred to as "diaper 2"), as shown in Figure 10, may also be used. Figure 10 is a diagram illustrating another embodiment. With respect to diaper 2, parts that are common to the configuration of the embodiments described above will be given the same reference numerals, etc., and a detailed explanation of the basic configuration of diaper 2 will be omitted.

[0117] The tape-type disposable diaper 2 comprises a front waistband portion 30a, a rear waistband portion 40a, and an absorbent (not shown). By locking the locking portion 48 provided on the rear waistband portion 40a to the front waistband portion 30a, it becomes a pant-like garment as shown in Figure 10. The pant-like diaper 2 comprises a waistband opening BH and a pair of leg openings LH. In this pant-like diaper 2, the area above the upper end of the leg openings LH is called the "waistband portion 20," and the area below the upper end of the leg openings LH is called the "crotch area 50." The waistband portion 20 of the diaper 2 includes a colored portion S. The colored portion S of the diaper 2 is a partially colored area of ​​the skin-side sheets 31, 41 located closer to the skin than the non-skin-side sheets 32, 42, which constitute at least a part of the non-skin side of the diaper 2. When the waist area 20 absorbs the wearer's sweat, the colored area S appears darker, making it easier for the wearer to perceive that the waist area 20 of the diaper 2 is absorbing sweat, and that the portion of the waist area 20 with the colored area S is absorbing the wearer's sweat and allowing the absorbed moisture to evaporate.

[0118] In the tape-type disposable diaper 2 shown in Figure 10, a colored portion S formed by coloring a part of the skin-facing sheets 31 and 41 has been described, but the invention is not limited to this. The colored portion S may be provided on any of the stretchable members (not shown) that expand and contract in the left-right direction, which are provided on the non-skin-facing sheets 32 and 42 or the waist portions 30a and 40a. Furthermore, the colored portion S may be a coloring of the entire area of ​​each of the stretchable members of the skin-facing sheets 31 and 41, the non-skin-facing sheets 32 and 42, or it may be a coloring of only a part of each of the members. [Explanation of symbols]

[0119] 1. Diapers (disposable diapers, absorbent items), 1e Side joint (one side joint, other side joint), 2. Diapers (disposable diapers, absorbent items), 10 Absorbent body, 11 Absorbent core, 11b Core wrap sheet, 12 top sheets, 13 back seats, 13a Liquid-impermeable sheet (leak-proof sheet), 13b Exterior sheet, 15 Leakage prevention wall section, 16. Leak-proof wall elastic member, 17. Elastic components around the legs, 20 Waist area, 30 Front band member, 30a Front body section, 30h opening, 31 Skin-facing sheet (hydrophobic part), 32 Non-skin side sheet (hydrophilic part), 35 Elastic member around the torso, 36 Skin-facing sheet (colored part on the other side), 40 Rear side band member, 40a Rear body section, 40b Buttocks cover, 40h opening, 41 Skin-facing sheet (hydrophobic part), 42 Non-skin side sheet (hydrophilic part), 45 Elastic member around the torso, 46 Skin-facing sheet (colored part on one side), 47. Curved elastic member, 50 inseam, BH (Body opening), LH leg opening, S colored part

Claims

1. It has intersecting vertical and horizontal directions, An absorbent body equipped with a liquid-absorbing core, A pair of waist portions provided on the non-skin side of the absorbent core, An absorbent article having, Having a colored part, At least one of the aforementioned body parts has a hydrophobic portion and a hydrophilic portion, The hydrophilic portion is at least a part of the non-skin side of one of the torso sections, When viewed from the non-skin side, At least a portion of the hydrophobic portion and the hydrophilic portion overlap, At least a portion of the hydrophilic portion and the colored portion overlap, The colored portion is a sheet member provided on the skin side of the hydrophobic portion. In the aforementioned torso portion, the sheet member is provided above the absorbent core. In the aforementioned vertical direction, the lower end of the sheet member and the upper end of the absorbent core are separated by a predetermined distance. When viewed from the non-skin side, the sheet member has a portion that overlaps with the absorbent body. An absorbent article characterized in that the lower end of the colored portion has a non-jointed portion in the thickness direction of one of the body portions that is not joined to the colored portion and the adjacent member.

2. The absorbent article according to claim 1, A liquid-impermeable leak-proof sheet is provided on the non-skin side of the absorbent core. An absorbent article characterized in that, in one of the torso portions, the colored portion is provided above the leak-proof sheet.

3. An absorbent article according to claim 1 or 2, The absorbent article is characterized in that the upper end of the colored portion is located below the upper end of one of the waist portions.

4. An absorbent article according to any one of claims 1 to 3, The hydrophobic portion and the hydrophilic portion each have fibers, An absorbent article characterized in that the fiber density of the hydrophobic portion is lower than the fiber density of the hydrophilic portion.

5. An absorbent article according to any one of claims 1 to 4, The colored portion has fibers, The absorbent article is characterized in that the colored portion has a compressed portion that is compressed in the thickness direction of one of the body circumference portions.

6. The absorbent article according to claim 5, An absorbent article characterized in that, in the compressed portion, the colored portion and adjacent members adjacent in the thickness direction are compressed in the thickness direction.

7. An absorbent article according to any one of claims 1 to 6, The color of the aforementioned colored part appears darker when the one of the body parts absorbs moisture than before it absorbed moisture. Areas that appear as darker colors are, A first colored portion that is visible at a predetermined intensity of color, A second colored portion that is lighter in color than the first colored portion, An absorbent article characterized by having [a certain property].

8. An absorbent article according to any one of claims 1 to 7, The hydrophobic portion is a hydrophobic portion on one side, the hydrophilic portion is a hydrophilic portion on one side, and the colored portion is a colored portion on one side. Of the aforementioned body sections, the other body section has a hydrophobic section on the other side and a hydrophilic section on the other side. The other hydrophilic portion is at least a part of the non-skin side of the other torso portion, The other side has a colored portion on the other side, When viewed from the non-skin side of the other torso portion, At least a portion of the hydrophobic portion on the other side and the hydrophilic portion on the other side overlap, An absorbent article characterized in that at least a portion of the hydrophilic portion on the other side and the colored portion on the other side overlap.

9. The absorbent article according to claim 8, An absorbent article characterized in that the upper end of the colored portion on one side and the upper end of the colored portion on the other side are located at different positions.

10. An absorbent article according to any one of claims 1 to 9, The left and right ends of the aforementioned body section have a one-side joint and a other-side joint, respectively, where the one body section and the other body section are joined together. On one side in the left-right direction, An absorbent article characterized in that one side end of the colored portion is provided outside the one-side joint portion.

11. An absorbent article according to any one of claims 1 to 10, The absorbent article is characterized in that the colored portion is provided on the skin side of the hydrophilic portion.

12. The absorbent article according to claim 11, An absorbent article characterized in that the brightness of the colored portion is lower than the brightness of the hydrophilic portion.

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