Underpants-type absorbent article

Abstract

An underpants-type absorbent article (1) comprises an absorbent body (10), a front side waist member (20), a back side waist member (30), and an extension part (30B) extending downward. The underpants-type absorbent article (1) has a crotch elastic member (17) which is stretchable along the longitudinal direction. The extension part (30B) is provided with an extension part elastic member (35) which is linearly disposed along the left-right direction. The underpants-type absorbent article (1) has a central non-stretchable part (BCN) and a side edge non-stretchable part (BSN). In the left-right direction, the length (L2) of the central non-stretchable part (BCN) on a virtual extension line of the extension part elastic member (35) is longer than the length (L1) of a part where the crotch elastic member (17) is provided, and the length (L2) of the central non-stretchable part (BCN) on the virtual extension line is longer than the length (L3) of the side edge non-stretchable part (BSN) on the virtual extension line.

Description

Pants-type absorbent article

[0001] The present invention relates to a pants-type absorbent article.

[0002]

[0003] Conventionally, in a pants-type absorbent article (e.g., a shorts-type napkin) including an absorbent main body and waist-line members arranged to cover the front and rear of the absorbent main body from the non-skin side, a technique has been known in which elastic members (crotch elastic members) that stretch along the longitudinal direction of the absorbent main body are provided to improve the fit of the absorbent main body in the crotch region. Among such pants-type absorbent articles, there is one in which waist-line elastic members that stretch in the left-right direction (a direction perpendicular to the longitudinal direction) are provided to ensure a good fit around the waist. For example, Patent Document 1 discloses a pants-type absorbent article in which a plurality of elastic members 15 (corresponding to crotch elastic members) that stretch in the longitudinal direction are arranged in the absorbent main body 11, and a plurality of elastic members 31 (corresponding to waist-line elastic members) that stretch in the width direction (left-right direction) are arranged in the pants-type outer body 21, thereby improving the fit in the crotch region and the waist region.

[0003] Japanese Patent Application Laid-Open No. 2002-209942

[0004] However, in a pants-type absorbent article having crotch elastic members and waist elastic members as in Patent Document 1, if the lateral stretching force of the waist elastic members interferes with the longitudinal stretching force of the crotch elastic members, the stretching force of the crotch elastic members is weakened, which may result in poor fit in the crotch area (for example, the buttocks crease or the vaginal opening).In addition, if the waist elastic members or the crotch elastic members are pressed strongly against the skin, the rigidity of the elastic members may cause a poor feel against the skin.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a pants-type absorbent article that is pleasant to the touch and has an absorbent main body that fits well in the crotch area.

[0006] The main invention for achieving the above object is a pants-type absorbent article having an absorbent main body with an absorbent core, a front waistline member, and a rear waistline member, the front waistline member and the rear waistline member being joined together in an annular shape by a pair of side joining parts, the article having a crotch elastic member that stretches along the longitudinal direction of the absorbent main body at a central part in the left-right direction and closer to the skin than the absorbent core, and at least one of the front waistline member and the rear waistline member has an extension part that extends downward in the up-down direction beyond the lower end of the side joining part, and the extension part has an extension part elastic member that is linearly arranged along the left-right direction. The extension portion has a central non-stretchable portion in the left-right central portion where the extension-portion elastic members are discontinuous and therefore no stretching force acts thereon, and side end non-stretchable portions in the left-right side portions where the extension-portion elastic members are discontinuous and therefore no stretching force acts thereon, and when the article is unfolded and stretched, the length of the central non-stretchable portion on an imaginary extension line of the extension-portion elastic members is longer in the left-right direction than the length from the most one end to the most other end of the portion where the crotch elastic members are provided, and the length of the central non-stretchable portion on the imaginary extension line is longer than the length of the side end non-stretchable portions on the imaginary extension line. Other features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[0007] According to the present invention, it is possible to provide a pants-type absorbent article that is pleasant to the touch and has an absorbent main body that fits well in the crotch area.

[0008] 3A is a front view of the pants-type absorbent article 1 as seen from the ventral side. FIG. 3B is a plan view of the pants-type absorbent article 1 in an unfolded and stretched state as seen from the skin side. FIG. 3A is a schematic cross-sectional view taken along the first center line CL1 in FIG. 2, and FIG. 3B is a schematic cross-sectional view taken along the second center line CC1 in FIG. 2. FIG. 3B is a diagram illustrating a method for manufacturing the waistline members 20, 30. FIG. 3B is a plan view illustrating an enlarged view of the rear waistline portion 30 and the absorbent main body 10 of the absorbent article 1 in an unfolded and stretched state. FIG. 6A and FIG. 6B are diagrams illustrating an example of a folding method for the absorbent article 1. FIG. 7A and FIG. 7B are diagrams illustrating a method of using the post-treatment tape 60. FIG. 9A and FIG. 9B are diagrams illustrating an example of the arrangement of the welded portion 50 in the extension portion 30B of the rear waistline member 30. FIG. 9A and FIG. 9B are diagrams illustrating the principle by which the extension portion elastic member 35 is attached to the extension portion 30B by the welded portion 50. 10A and 10B are diagrams illustrating the arrangement of the extension elastic members 35 and the welded portion pairs 50s at the left and right ends of the extension 30B.

[0009] The present specification and the accompanying drawings make clear at least the following: (Aspect 1) A pants-type absorbent article having an absorbent main body with an absorbent core, a front waistline member, and a rear waistline member, the front waistline member and the rear waistline member being joined together in an annular shape by a pair of side joints, the article having a crotch elastic member stretchable along the longitudinal direction of the absorbent main body at a central portion in the left-right direction and closer to the skin than the absorbent core, at least one of the front waistline member and the rear waistline member having an extension portion extending downward in the up-down direction beyond a lower end of the side joint portion, the extension portion being provided with an extension portion elastic member linearly arranged along the left-right direction, The extension portion has a central non-stretchable portion where no stretching force is applied because the extension portion elastic member is discontinuous at the center in the left-right direction, and side end non-stretchable portions where no stretching force is applied because the extension portion elastic member is discontinuous at the side end portions in the left-right direction, and when the extension portion is unfolded and stretched, the length of the central non-stretchable portion on an imaginary extension line of the extension portion elastic member is longer than the length from the most one end to the most other end of the portion where the crotch elastic member is provided in the left-right direction, and the length of the central non-stretchable portion on the imaginary extension line is longer than the length of the side end non-stretchable portions on the imaginary extension line.

[0010] According to the pants-type absorbent article of Aspect 1, by providing a central non-stretchable portion in the extension portion near the crotch portion, the stretchable force of the crotch elastic members is less likely to be interfered with by the stretchable force of the extension portion elastic members, the absorbent core is more likely to fit in the crotch portion (the buttocks crease and the vaginal opening), and leakage of body waste along the skin is more likely to be suppressed. Furthermore, by providing side end non-stretchable portions that are narrower than the central non-stretchable portion on both side ends of the extension portion, the fit is improved over as wide a range as possible in the left-right direction of the extension portion, while the side end edges of the extension portion are less likely to be pressed against the wearer's skin, making it easier to achieve a comfortable feel against the skin.

[0011] (Aspect 2) A pants-type absorbent article as described in Aspect 1, wherein the extension portion has a skin-side sheet arranged on the skin side of the extension portion elastic member and a non-skin-side sheet arranged on the non-skin side of the extension portion elastic member, and the side end non-elastic portion on the virtual extension line has a portion where the skin-side sheet and the non-skin-side sheet are joined to each other.

[0012] In the pants-type absorbent article of Aspect 2, the skin-side sheet and the non-skin-side sheet are bonded to each other at the left and right side edges of the extension portions, and have portions that are in close contact in the thickness direction, which makes it easier to prevent the edges of the extension portions from rolling up or the elastic members of the extension portions from further contracting inward in the left and right direction when worn, thereby making it easier to maintain a good fit and feel against the skin for a long period of time.

[0013] (Aspect 3) A pants-type absorbent article according to Aspect 1 or 2, wherein the extension portion has a skin-side sheet arranged on the skin side of the extension portion elastic member and a non-skin-side sheet arranged on the non-skin side of the extension portion elastic member, the skin-side sheet and the non-skin-side sheet being joined to each other by a plurality of scattered welds, the spacing between a pair of adjacent welds in the vertical direction is smaller than the diameter of the extension portion elastic member in its natural state, the position of the extension portion elastic member in the vertical direction is restricted by being sandwiched between the pair of welds, and the pair of welds that are located outermost in the left-right direction on the imaginary extension line are arranged at a position spaced a predetermined distance inward from the outer end of the extension portion.

[0014] According to the pants-type absorbent article of Aspect 3, the welded portions are provided at positions spaced from the edges of the extension portions, and the extension-portion elastic members are stably fixed by the welded portions, which makes it easier to prevent the side-end non-stretched portions from widening further. Therefore, the side-end non-stretched portions are less likely to become excessively large, making it easier to maintain a good fit and feel against the skin for a long period of time when worn.

[0015] (Aspect 4) The pants-type absorbent article according to any one of Aspects 1 to 3, wherein on the imaginary extension line, the distance in the left-right direction between the end closest to one side of the portion where the crotch elastic members are provided and the end of one side of the central non-stretchable portion is longer than the length of the side end non-stretchable portion.

[0016] In the pants-type absorbent article of Aspect 4, the stretching force of the crotch elastic members is less likely to act on both sides of the portion where the stretching force of the crotch elastic members is acting, which makes it easier to suppress contraction of the absorbent core. Therefore, the portion of the absorbent core that is less likely to contract becomes larger, and this non-contracting portion is more likely to deform along the curves of the wearer's body. This improves the fit in the crotch area.

[0017] (Aspect 5) The pants-type absorbent article according to any one of Aspects 1 to 4, wherein, on the imaginary extension line, one end of the central non-stretchable portion is located to one side of one end of the absorbent core in the left-right direction.

[0018] According to the pants-type absorbent article of aspect 5, the extension-portion elastic members do not overlap with the absorbent core, making it difficult for the stretching force of the extension-portion elastic members to act on the absorbent core. Therefore, the absorbent core is less likely to be pulled in the left-right direction by the extension-portion elastic members and to be contracted. This makes it easier for the absorbent core to maintain a snug fit in the buttocks and vaginal opening when worn. Furthermore, since gaps are less likely to form between the absorbent core and the wearer's body, it is easier to prevent leakage of excrement.

[0019] (Aspect 6) The pants-type absorbent article according to any one of Aspects 1 to 5, wherein, on the imaginary extension line, one end of the central non-elastic portion is located on the other side of one end of the absorbent main body in the left-right direction.

[0020] According to the pants-type absorbent article of Aspect 6, the stretching force of the extension-portion elastic members pulls both side portions of the absorbent main body outward in the left-right direction, making it easier for the entire absorbent main body to fit the wearer's body widely. Also, the absorbent main body is prevented from being pushed too far into the wearer's groin area and becoming twisted due to body or leg movements.

[0021] (Aspect 7) The pants-type absorbent article according to any one of Aspects 1 to 6, wherein the extension portion is provided on the rear waistband member and not on the front waistband member.

[0022] According to the pants-type absorbent article of Aspect 7, the extension portions function as buttock covers on the back side of the wearer. On the other hand, since no extension portions are provided on the ventral side of the wearer, when the wearer moves their legs forward while wearing the absorbent article, for example, by walking, the movement of the legs is less likely to be hindered by the extension portions. Therefore, when the absorbent article is worn, a good fit and mobility are ensured, and the absorbent article can be worn comfortably.

[0023] (Aspect 8) The pants-type absorbent article according to any one of Aspects 1 to 7, wherein in a deployed and stretched state, the article has a longitudinal direction and a left-right direction that are perpendicular to each other, the crotch elastic members are continuous along the longitudinal direction, and in the longitudinal direction, the rear ends of the crotch elastic members are located rearward of the front ends of the side joint portions provided on the rear waistband member.

[0024] According to the pants-type absorbent article of Aspect 8, the stretching force of the crotch elastic members acts over a wide range from the crotch to the buttocks of the wearer, making it easier for the absorbent core to fit along the buttocks of the wearer, thereby preventing excreted fluid from leaking along the buttocks.

[0025] (Aspect 9) A pants-type absorbent article according to any one of Aspects 1 to 8, wherein the rear waistline member has a rear waistline elastic member that stretches along the left-right direction, the rear waistline member has a rear waistline central non-stretchable portion at a center in the left-right direction where the rear waistline elastic member is discontinuous and no stretching force acts, and the length of the rear waistline central non-stretchable portion on an imaginary extension line of the rear waistline elastic member is longer than the length in the left-right direction from the most one end to the most other end of the portion where the crotch elastic member is provided.

[0026] According to the pants-type absorbent article of aspect 9, the effective length ranges of the crotch elastic members and the waist elastic members do not overlap, so the elastic forces of the crotch elastic members and the waist elastic members are less likely to interfere with each other, and the absorbent core and the rear waist portion can provide good fit over a wide area on the back of the wearer.

[0027] (Aspect 10) The pants-type absorbent article according to any one of Aspects 1 to 9, wherein in a deployed and stretched state, the pants-type absorbent article has a longitudinal direction and a left-right direction that are perpendicular to each other, and in the longitudinal direction, the front ends of the crotch elastic members are located further rearward than the rear ends of the front waistband members.

[0028] According to the pants-type absorbent article of Aspect 10, the range over which the stretchability of the crotch elastic members acts is shorter on the front side (ventral side) than on the rear side (back side), so the force pushing the absorbent core up against the wearer's skin is less likely to become excessively large, and the absorbent core is less likely to be pressed strongly against the wearer's urethral opening or vaginal opening. This prevents the absorbent core from fitting too tightly to the excretory opening, thereby preventing discomfort such as pain from being caused to the wearer, and improves the comfort of the pants-type absorbent article.

[0029] (Aspect 11) The pants-type absorbent article according to any one of Aspects 1 to 10, wherein, in the longitudinal direction, the front ends of the crotch elastic members are located forward of a center position of the pants-type absorbent article, and the front ends of the extension portions provided on the rear waistband members are located rearward of the center position.

[0030] According to the pants-type absorbent article of Aspect 11, the crotch elastic members extend forward of the crotch portion when worn, allowing the absorbent core to fit securely in the rear region of the vaginal opening. Meanwhile, the front end of the buttocks cover (extension portion) is located behind the crotch portion when worn, preventing the buttocks cover from interfering with leg movement or causing discomfort when walking, etc., thereby further improving fit and feel.

[0031] (Aspect 12) A pants-type absorbent article according to any one of Aspects 1 to 11, wherein the front waistline member and the rear waistline member each have waistline elastic members that stretch along the left-right direction, and have fold lines on both sides in the left-right direction along which the pants-type absorbent article is folded in thirds in the left-right direction, the waistline elastic members are arranged across the fold lines in the left-right direction, and the crotch elastic members are arranged across a central position of the pants-type absorbent article in the longitudinal direction.

[0032] According to the pants-type absorbent article of Aspect 12, the elastic force of the waist elastic members is likely to act at the fold lines where the absorbent article is folded in thirds in the left-right direction, thereby preventing the absorbent main body from being deformed by external forces acting in the left-right direction during distribution. Similarly, the elastic force of the crotch elastic members is likely to act at the center position where the absorbent article is folded in half in the longitudinal direction, thereby preventing the absorbent main body from being deformed by external forces acting in the longitudinal direction during distribution.

[0033] (Aspect 13) The pants-type absorbent article according to any one of Aspects 1 to 12, wherein a post-treatment tape is provided on a non-skin side of the rear waistband member, the post-treatment tape being used when disposing of the pants-type absorbent article after use, and an angle formed between a longitudinal direction of the post-treatment tape and a longitudinal direction of the absorbent main body is greater than 0 degrees.

[0034] In the pants-type absorbent article of aspect 13, the diagonal arrangement of the post-treatment tape widens the area secured by the post-treatment tape in the left-right direction when the absorbent article is rolled up for disposal after use, making it easier to maintain the rolled-up state of the absorbent article. Furthermore, when wrapping the post-treatment tape around the absorbent article while pulling it in the longitudinal direction, the stretching force of the crotch elastic members along the longitudinal direction is utilized to facilitate the wrapping operation, and the wrapped state is also easily maintained. This makes it easier to dispose of the absorbent article.

[0035] First Embodiment Hereinafter, a pants-type absorbent article 1 according to a first embodiment of the present invention will be described. The pants-type absorbent article 1 according to the first embodiment is a pants-type disposable diaper, a shorts-type sanitary napkin, or the like.

[0036] <Basic structure of pants-type absorbent article 1> Fig. 1 is a front view of the pants-type absorbent article 1 as seen from the ventral side. Fig. 2 is a plan view of the pants-type absorbent article 1 in an unfolded and stretched state as seen from the skin side. Fig. 3A is a schematic cross-sectional view taken along the first center line CL1 in Fig. 2, and Fig. 3B is a schematic cross-sectional view taken along the second center line CC1 in Fig. 2. In the following description, the pants-type absorbent article will also be simply referred to as the "absorbent article." The first center line CL1 is a line extending in the left-right direction at a center point that divides the product (absorbent article 1) in half in the longitudinal direction, and the second center line CC1 is a line extending in the longitudinal direction at a center point that divides the product in half in the left-right direction.

[0037] The unfolded state of the pants-type absorbent article 1 is a state in which the pair of side joining portions 2 provided on both sides of the absorbent article 1 are separated and the absorbent article 1 is opened and unfolded in a plane. The stretched state of the pants-type absorbent article 1 is a state in which the absorbent article 1 is stretched to an extent that wrinkles in the absorbent article 1 are no longer visible. Specifically, it is a state in which the absorbent article 1 is stretched until the dimensions of each component constituting the absorbent article 1 match or are close to the dimensions of the component alone.

[0038] As shown in Fig. 1, the pants-type absorbent article 1 has a vertical direction, a horizontal direction, and a front-to-rear direction (directions passing through the paper in Fig. 1) that are perpendicular to one another, and has a waist opening BH and a pair of leg openings LH. The upper side in the vertical direction corresponds to the waist opening BH side, and the lower side corresponds to the crotch side. The front side in the front-to-rear direction corresponds to the wearer's abdomen side, and the rear side corresponds to the wearer's back side.

[0039] 2, the absorbent article 1 has a longitudinal direction, a left-right direction, and a thickness direction (a direction passing through the paper in FIG. 2) that intersect with one another. The left-right direction in the unfolded state of FIG. 2 is the same as the left-right direction in the pants-type state of FIG. 1. The longitudinal direction in the unfolded state is a direction along the up-down direction in the pants-type state. One side in the longitudinal direction corresponds to the front side (ventral side), and the other side corresponds to the rear side (dorsal side). As shown in FIGS. 3A and 3B, the direction in which the materials constituting the absorbent article 1 are layered is referred to as the thickness direction. In the thickness direction, the side that comes into contact with the wearer's skin is referred to as the skin side, and the opposite side is referred to as the non-skin side.

[0040] The pants-type absorbent article 1 is a so-called three-piece pants-type absorbent article that includes at least three members: an absorbent main body 10, a front waistline member 20 that covers the abdominal region of the wearer, and a rear waistline member 30 that covers the dorsal region of the wearer and is configured as a separate member from the front waistline member 20. In the following description, the front waistline member 20 and the rear waistline member 30 will also be collectively referred to as the waistline members 20, 30.

[0041] As shown in Fig. 2, in the unfolded absorbent article 1, the front waistline member 20 and the rear waistline member 30 are positioned side by side at a longitudinal interval, and the absorbent main body 10 is suspended between them in the longitudinal direction. One longitudinal end 10F of the absorbent main body 10 is joined and fixed to the skin side of the front waistline member 20, and the other longitudinal end 10B of the absorbent main body 10 is joined and fixed to the skin side of the rear waistline member 30. From this state, the absorbent main body 10 is folded in half longitudinally, and the opposing front waistline member 20 and rear waistline member 30 are joined at their left and right side ends by a pair of side joining portions 2, resulting in the pants-type absorbent article 1 as shown in Fig. 1. In other words, the front waistline member 20 and the rear waistline member 30 are joined in an annular shape by the pair of side joining portions 2. Examples of the joining method using the side joining portion 2 include heat welding, ultrasonic welding, and joining methods using adhesives.

[0042] The absorbent body 10 comprises an absorbent core 11 that absorbs and retains excreted liquids such as urine, a liquid-permeable topsheet 12 (e.g., nonwoven fabric, perforated film, etc.) arranged closer to the skin than the absorbent core 11, a liquid-impermeable backsheet 13 (e.g., resin film, etc.) arranged closer to the skin than the absorbent core 11, and a sheet member 14 (e.g., hydrophobic nonwoven fabric, etc.). The absorbent core 11 may be covered on both the skin side and the non-skin side in the thickness direction with a liquid-permeable core wrap sheet 15 such as tissue paper or nonwoven fabric. The sheet member 14 is arranged closer to the skin than the backsheet 13 and forms a leakage prevention wall portion 3 closer to the skin than the topsheet 12.

[0043] The absorbent core 11 is a molded body obtained by molding a predetermined liquid-absorbent material into a rectangular shape in a plan view, which is an example of a predetermined shape (see FIG. 2 ). Examples of the liquid-absorbent material include water-retentive fibers and liquid-absorbent granular materials such as superabsorbent polymers (so-called SAPs). The water-retentive fibers are not particularly limited as long as they have the property of absorbing and retaining moisture, and examples thereof include cellulosic fibers (e.g., pulp fibers, non-wood fibers such as cotton and hemp, and recycled fibers such as rayon). However, the shape of the absorbent core 11 is not limited to the rectangular shape shown in FIG. 2 . For example, the absorbent core 11 may be roughly hourglass-shaped, with a narrow width in the left-right direction between one end (front) and the other end (rear) in the longitudinal direction.

[0044] As shown in Figures 2 and 3A, a pair of leakage preventing walls 3 is provided along the longitudinal direction of the absorbent main body 10 on both left and right side portions of the absorbent main body 10. The pair of leakage preventing walls 3 is formed integrally with the absorbent main body 10 by folding a sheet member 14 constituting the exterior of the absorbent main body 10. Specifically, the sheet member 14 covers the non-skin side of the back sheet 13, and portions extending outward in the left and right direction are folded at multiple locations to form the leakage preventing walls 3 on both left and right side portions of the skin side of the top sheet 12. Leak preventing wall elastic members 16 (e.g., rubber thread) are attached to the leakage preventing walls 3 in a stretched state along the longitudinal direction. When the absorbent article 1 is worn, the leakage preventing walls 3 rise up toward the wearer's skin due to the longitudinal stretchability of the leakage preventing wall elastic members 16.

[0045] The absorbent body 10 also has a crotch elastic member 17 that is stretchable in the longitudinal direction at the center in the left-right direction and on the non-skin side in the thickness direction of the absorbent core 11. Specifically, the crotch elastic member 17 in this embodiment is sandwiched and joined between the core wrap sheet 15 that covers the non-skin side of the absorbent core 11 and the back sheet 13 that is arranged on the non-skin side of the core wrap sheet 15 (absorbent core 11) in the thickness direction.

[0046] The front waistline member 20 includes a skin-side sheet 21, a non-skin-side sheet 22 laminated on the non-skin side of the skin-side sheet 21, and a plurality of front waistline elastic members 23 (e.g., rubber thread) that stretch in the left-right direction. Similarly, the back waistline member 30 includes a skin-side sheet 31, a non-skin-side sheet 32 ​​laminated on the non-skin side of the skin-side sheet 31, and a plurality of rear waistline elastic members 33 (e.g., rubber thread) that stretch in the left-right direction. The plurality of front (rear) waistline elastic members 23 (33) are arranged side by side at a predetermined interval in the vertical direction (longitudinal direction) between the skin-side sheet 21 (skin-side sheet 31) and the non-skin-side sheet 22 (non-skin-side sheet 32) and are attached in a stretched state in the left-right direction. The stretchability of the front and rear waistline elastic members 23, 33 allows the front waistline member 20 and the rear waistline member 30 to fit the waist of the wearer. Furthermore, a post-treatment tape 60 may be provided on the non-skin side of the rear waistband member 30, which is used when the absorbent article 1 is rolled up and disposed of after use (see FIGS. 2 and 3B). Details of the post-treatment tape 60 will be described later.

[0047] 2, the front waistline member 20 and the rear waistline member 30 have different planar shapes in the unfolded and stretched state. The front waistline member 20 has a rectangular shape that is elongated in the left-right direction and has a vertical length that is roughly the same as that of the side joint portion 2. On the other hand, the rear waistline member 30 has a rectangular waist side portion 30A that overlaps with the front waistline member 20, and an extension portion 30B that extends below the lower end 2ed of the side joint portion 2 (to one side of one longitudinal end of the side joint portion 2) and whose width in the left-right direction narrows from the upper side to the lower side in the vertical direction (from the other longitudinal side to one side). This extension portion 30B functions as a buttocks cover that covers the wearer's buttocks on the rear side (back side) when the absorbent article 1 is worn.

[0048] The extension portion 30B is provided with rear extension portion elastic members 35 (e.g., rubber threads) extending in the left-right direction. A plurality of rear extension portion elastic members 35 are provided in the extension portion 30B at predetermined intervals in the longitudinal direction (vertical direction) as shown in FIG. 2 . The rear extension portion elastic members 35 are also attached in a stretched state between the skin side sheet 31 and the non-skin side sheet 32. The stretchability of the rear extension portion elastic members 35 allows the extension portion 30B of the rear waistband member 30 to fit easily around the wearer's buttocks and to be less likely to roll up from the buttocks. Although FIG. 2 illustrates three rubber threads as the rear extension portion elastic members 35, the number of rubber threads is not particularly limited.

[0049] 2, the extension portion 30B is provided only on the rear waistline member 30, but the front waistline member 20 may be provided with an extension portion (not shown) that extends downward beyond the lower end 2ed of the side joint portion 2. Furthermore, it is sufficient that the extension portion is provided on at least one of the front waistline member 20 and the rear waistline member 30.

[0050] In the absorbent article 1 of the first embodiment, the waist elastic members 23, 33 and the rear extension elastic members 35 are attached to the front waist member 20 and the rear waist member 30, respectively, using an adhesive such as a hot melt adhesive. Specifically, the surface of each elastic member 23, 33, 35 is continuously or intermittently coated with adhesive in the left-right direction (the direction in which the elastic members stretch) in FIG. 2 , and the adhesive-coated elastic members 23, 33, 35 are sandwiched between the skin-side sheet 21 (31) and the non-skin-side sheet 22 (32). This bonds the skin-side sheet 21 (31) and the non-skin-side sheet 22 (32) in the thickness direction via the adhesive coated on the elastic members 23, 33, 35, allowing the elastic members 23, 33, 35 to stretch in the left-right direction. Similarly, the crotch elastic members 17 are attached to the absorbent main body 10 using an adhesive such as a hot melt adhesive.

[0051] The basic configuration of the absorbent article 1 has been described above, but the configuration of the absorbent article 1 described above is an example and is not limited thereto. For example, a liquid-permeable intermediate sheet may be provided between the topsheet 12 and the core wrap sheet 15 of the absorbent main body 10. Furthermore, a stretchable sheet may be provided in place of the thread-like waist elastic members 23, 33 in a portion of the waistband members 20, 30 (for example, the upper end portion in the vertical direction). By providing a stretchable sheet between the skin-side sheet 21 (skin-side sheet 31) and the non-skin-side sheet 22 (non-skin-side sheet 32) and intermittently joining the stacked sheets, the waistband members 20, 30 may exhibit stretchability and provide a soft surface fit around the waist of the wearer.

[0052] <Regarding the Fit of the Absorbent Article 1> The absorbent article 1 achieves a good fit and a comfortable feel due to the stretchability of the crotch elastic members 17 provided on the absorbent main body 10, and the stretchability of the waist elastic members 23, 33 and the extension elastic members 35 provided on the waist members 20, 30. The stretchability of each elastic member will be described in detail below.

[0053] First, a brief description will be given of a method for attaching the elastic members 23, 33, 35 in the process of manufacturing the front waistline member 20 and the rear waistline member 30. Fig. 4 is a diagram illustrating a manufacturing method of the waistline members 20, 30.

[0054] In the manufacturing process of the absorbent article 1, the front waistline member 20 and the rear waistline member 30 are each formed by attaching elastic members 23, 33, 35 while conveying a continuous body of base sheets 21, 22, 31, 32 in a conveying direction that is along the left-right direction of the absorbent article 1. Each of the elastic members 23, 33, 35 is stretched in the conveying direction with an adhesive applied to its surface, and is attached by being sandwiched between the skin-side sheet 21 (31) and the non-skin-side sheet 22 (32). As a result, the skin-side sheet 21 (31) and the non-skin-side sheet 22 (32) are joined via the elastic members 23, 33, 35 in a state where they are stacked in the thickness direction. Furthermore, in the extension portion 30B of the rear waistline member 30, the number of extension portion elastic members 35 arranged is small (three in the absorbent article 1) and they are arranged at wide intervals, so a hot melt adhesive (HMA) is separately applied to the region between the two extension portion elastic members 35, 35 in the longitudinal direction, as shown in Figure 4. This prevents the skin side sheet 31 and the non-skin side sheet 32 ​​from peeling apart in the extension portion 30B, and prevents deterioration of fit and feel in the buttocks.

[0055] After the skin side sheet 21 (31) and the non-skin side sheet 22 (32) are joined in the thickness direction, parts of the elastic members 23, 33, 35 are cut to form areas in which no stretching force is exerted in the front waistline member 20 and the rear waistline member 30. In the absorbent article 1, parts of the elastic members 23, 33, 35 are shredded in the areas of the waistline members 20, 30 that overlap with the absorbent main body 10 (areas indicated by dashed lines in Fig. 4 ), so that no stretching force is exerted in the shredded areas.

[0056] In Figure 4, the waist elastic members 23 are cut (shred) at multiple locations in a region FC at the center in the left-right direction of the front waistline member 20. The cut waist elastic members 23 contract in the left-right direction from the cut locations, releasing their elongated state and resulting in a state in which they do not exert any stretching force. As a result, the waist elastic members 23 become discontinuous in the left-right direction between an end FCl on one side (the left side in Figure 4) of the region FC and an end FCr on the other side (the right side in Figure 4), and no stretching force acts on them. Hereinafter, this portion where no stretching force acts is also referred to as a central non-stretchable portion (front waistline central non-stretchable portion) FCN.

[0057] Similarly, in a region BC at the center in the left-right direction of the rear waistline member 30, the waistline elastic members 33 and the extension-portion elastic members 35 are cut (shred) at multiple locations. The cut elastic members 33, 35 contract laterally from the cut locations, releasing their elongated state and no longer exerting stretching force. As a result, the waistline elastic members 33 and the extension-portion elastic members 35 become discontinuous in the left-right direction between an end BCl on one side (left side in FIG. 4 ) of the region BC and an end BCr on the other side (right side in FIG. 4 ), and no stretching force acts on them. Hereinafter, this portion where no stretching force acts is also referred to as a central non-stretchable portion (rear waistline central non-stretchable portion) BCN (see FIG. 5 ).

[0058] The rear waistband member 30 is cut along the dashed line 30Be in the skin-side sheet 31 and the non-skin-side sheet 32 ​​to form a generally trapezoidal extension portion 30B. At this time, the extension portion elastic member 35 is also cut at the dashed line 30Be, and the extension portion elastic member 35 may contract slightly inward in the left-right direction from the cut point. As a result, the extension portion elastic member 35 becomes discontinuous in the left-right direction between the edge 30Be of the extension portion 30B and the outer end 35e0 of the contracted extension portion elastic member 35, and no stretching force acts on the extension portion elastic member 35. Hereinafter, this unstretched portion is also referred to as the side end non-stretched portion BSN (see FIG. 5). Because the extension portion elastic member 35 is sandwiched between the skin-side sheet 31 and the non-skin-side sheet 32 ​​with the adhesive applied, it does not shrink significantly. Even if it does shrink, the amount of shrinkage is only a few millimeters (e.g., 2.0 mm or less).

[0059] Fig. 5 is an enlarged plan view of the rear waistline member 30 and the absorbent main body 10 of the absorbent article 1 in an unfolded and stretched state. The rear waistline member 30 (waist side portions 30A and extension portions 30B) is provided with waistline elastic members 33 and extension portion elastic members 35 that stretch in the left-right direction. The waistline elastic members 33 and extension portion elastic members 35 have a central non-stretchable portion BCN in their left-right central portions where no stretching force is applied. Crotch elastic members 17 that stretch in the longitudinal direction of the absorbent main body 10 are provided in an area overlapping with this central non-stretchable portion BCN when viewed in the thickness direction. In other words, the waistline elastic members 33 and extension portion elastic members 35, which are discontinuous at the central non-stretchable portion BCN, are arranged so that the crotch elastic members 17 intersect with an imaginary extension line (shown by a dotted line in Fig. 5 ) obtained by extending the waistline elastic members 33 and extension portion elastic members 35 in the left-right direction.

[0060] In FIG. 5 , L1 is the length from the lateral end 17el to the lateral end 17er of the crotch elastic member 17, and L2 is the length of the central non-stretchable portion BCN on an imaginary extension of the waist elastic member 33 and the extension-portion elastic member 35. L2 is longer than L1 (L1<L2). This reduces the interference between the longitudinal stretching force of the crotch elastic member 17 and the lateral stretching force of the waist elastic member 33 and the extension-portion elastic member 35. In particular, in the extension portion 30B located near the wearer's crotch region, the stretching force of the crotch elastic member 17 is less likely to be interfered with by the stretching force of the extension-portion elastic member 35. As a result, the absorbent core 11 (absorbent main body 10) in the crotch region of the wearer is more likely to deform convexly toward the skin due to the stretching (contraction) of the crotch elastic member 17, providing a more snug fit around the buttocks and vaginal opening. This prevents excrement from leaking along the skin, etc. Furthermore, in the extension portion 30B, the stretching force of the extension portion elastic member 35 is less likely to be interfered with by the stretching force of the crotch elastic member 17. As a result, the extension portion elastic member 35 makes it easier for the extension portion 30B to fit the buttocks of the wearer. This prevents the extension portion 30B from rolling up, exposing the buttocks, etc.

[0061] 5, three rubber-thread crotch elastic members 17 are provided, but a band-like crotch elastic member 17 having a predetermined width in the left-right direction may be provided. In this case, the width of the band-like crotch elastic member 17 in the left-right direction is defined as length L1.

[0062] Furthermore, in the extension portion 30B of Figure 5, when the length of the side end non-stretchable portions BSN on an imaginary extension line of the extension portion elastic member 35 is L3, L2 is longer than L3 (L3 < L2). In other words, side end non-stretchable portions BSN that are narrower than the central non-stretchable portion BCN are provided at both left and right end portions of the extension portion 30B. If the width L3 of the side end non-stretchable portions BSN were longer than the width L2 of the central non-stretchable portion BCN, the left and right side portions of the extension portion 30B would be more likely to roll up from the wearer's buttocks, which could cause discomfort to the wearer. In response to this, by making the width L3 of the side end non-stretchable portion BSN as narrow as possible, the extension portion 30B fits widely around the wearer's buttocks, making it less likely to roll up, while preventing the side end edge of the extension portion 30B from being pressed against the wearer's skin, leaving linear marks (marks from the rubber thread) on the buttocks, thereby achieving a good fit and feel against the skin.

[0063] In the extension portion 30B shown in Fig. 5, the skin-side sheet 31 and the non-skin-side sheet 32 ​​are bonded to each other with adhesive at least in a portion of the side-end non-stretchable portion BSN on a virtual extension line of the extension-portion elastic member 35. This is because, when the edge 30Be of the extension portion 30B is cut as described in Fig. 4, the extension-portion elastic member 35 contracts inward in the left-right direction from the cut point (to the outer end 35e0 in Fig. 5), and some of the adhesive originally applied to the extension-portion elastic member 35 remains between the skin-side sheet 31 and the non-skin-side sheet 32 ​​in the side-end non-stretchable portion BSN. The sheet members 31, 32 are bonded to each other at the left-right side ends of the extension portion 30B, and have portions that are in close contact in the thickness direction. This helps prevent the ends of the extension portion 30B from rolling up or the extension-portion elastic member 35 from further contracting inward in the left-right direction (so-called rubber loss) when the absorbent article 1 is worn. That is, the side edge non-stretchable portions BSN are prevented from widening further, which makes it easier to maintain a good fit and comfortable feel against the skin for a long period of time when wearing the absorbent article 1.

[0064] Furthermore, when the length L4 is defined as the length from the end 17el of the crotch elastic member 17 to the end BC1 of the central non-stretchable portion BCN on an imaginary extension line of the discontinuous portion of the extension elastic member 35 in the left-right direction, L4 is longer than L3 (see FIG. 5 ). The stretchable force of the crotch elastic member 17 is less likely to act on the portions (L4) on both sides of the portion where the stretchable force of the crotch elastic member 17 acts (i.e., the effective length range of the crotch elastic member 17), which tends to suppress contraction of the absorbent core 11. Therefore, when L4 is longer than L3, the portion of the absorbent core 11 that is less likely to contract is larger than in the opposite case, and this non-contractable portion is more likely to deform along the curves of the wearer's body. This improves fit in the crotch area.

[0065] Furthermore, on an imaginary extension line of the discontinuous portion of the extension-portion elastic member 35 extending in the left-right direction, one end BCl of the central non-stretchable portion BCN is located to one side of one end 11el of the absorbent core 11 in the left-right direction (see FIG. 5 ). In other words, when viewed in the thickness direction, the extension-portion elastic member 35 does not overlap with the absorbent core 11, making it difficult for the stretching force of the extension-portion elastic member 35 to act on the absorbent core 11. Therefore, the absorbent core 11 is less likely to be pulled or contracted in the left-right direction by the extension-portion elastic member 35. This prevents the absorbent core 11 from deforming in the left-right direction and forming wrinkles when the absorbent article 1 is worn, and helps maintain a good fit to the buttocks and vaginal opening. Furthermore, since gaps are less likely to form between the absorbent core 11 and the body, it is easier to prevent excretory fluid from leaking.

[0066] On the other hand, on an imaginary extension line of the discontinuous portion of the extension-portion elastic member 35 extending in the left-right direction, one end BCl of the central non-stretchable portion BCN is located on the other side of one end 10el of the absorbent main body 10 in the left-right direction (see FIG. 5 ). In other words, when viewed in the thickness direction, the extension-portion elastic member 35 does not overlap with the absorbent core 11, but does overlap with the absorbent main body 10. Therefore, the elastic force of the extension-portion elastic member 35 pulls both side portions of the absorbent main body 10 outward in the left-right direction, making it easier for the entire absorbent main body 10 to fit widely around the wearer's body. In addition, this prevents the absorbent main body 10 from getting too close to the wearer's groin and becoming twisted due to body or leg movement.

[0067] In the absorbent article 1 shown in Fig. 2, the extension portion 30B is provided only on the rear waistband member 30 side, and no extension portion is provided on the front waistband member 20 side. With this configuration, the extension portion 30B functions as a buttocks cover on the back side (rear side) of the wearer. On the other hand, because no extension portion is provided on the ventral side (front side) of the wearer, when the wearer wears the absorbent article 1 and moves their legs forward while walking, leg movement is less likely to be hindered by the extension portion on the front side. Therefore, when the absorbent article 1 is worn, good fit and mobility are ensured, and the absorbent article 1 can be worn comfortably.

[0068] 2 , in the longitudinal direction of the absorbent article 1 in the unfolded and stretched state, the rear end 17eb of the crotch elastic member 17 is located rearward of the front end 2ed of the side joint 2 of the rear waistline member 30. In other words, when the absorbent article 1 is in a pants-like state, the upper end (17eb) on the back side of the crotch elastic member 17 is located above the lower end (2ed) of the side joint 2. Therefore, at the back side (back side) of the absorbent article 1, the stretching force of the crotch elastic member 17 acts over a wide range of the rear waistline member 30 (waist side portions 30A and extension portions 30B) from the crotch region to the buttocks, making it easier for the absorbent core 11 to fit along the crease of the wearer's buttocks. This makes it possible to prevent excreted fluid from leaking along the crease of the buttocks.

[0069] Furthermore, because the rear end 17eb of the crotch elastic member 17, which is continuous in the longitudinal direction, is located rearward of the rear end of the extension portion 30B (the front end 2ed of the side joint portion 2), in the absorbent article 1, the crotch elastic member 17 and the imaginary extension line of the extension portion elastic member 35 necessarily intersect (see FIG. 5 ). However, as described above, the extension portion elastic member 35 has a central non-elastic portion BCN in the center in the left-right direction, and the effective length ranges of the crotch elastic member 17 and the extension portion elastic member 35 do not overlap and do not interfere with each other, so that the fit around the buttocks is unlikely to deteriorate.

[0070] Similarly, the crotch elastic members 17 also intersect with the imaginary extension of the waist elastic members 33 at the waist side portions 30A of the rear waistline member 30. However, the length L2 of the rear waistline central non-stretchable portion BCN on the imaginary extension of the waist elastic members 33 is longer than the length L1 from the most one end 17el to the most other end 17er of the portion where the crotch elastic members are provided in the left-right direction (L1<L2), and the effective length ranges of the crotch elastic members 17 and the waist elastic members 33 do not overlap (see FIG. 5 ). Therefore, the stretching force of the crotch elastic members 17 and the stretching force of the waist elastic members 33 are unlikely to interfere with each other, allowing the absorbent core 11 and the rear waistline member 30 to provide a good fit over a wide area on the back of the wearer.

[0071] Furthermore, in the longitudinal direction of the absorbent article 1 in the unfolded and stretched state, the front end 17ef of the crotch elastic member 17 is located rearward of the rear end 2ed of the side joint 2 of the front waistline member 20 (see FIG. 2 ). In other words, when the absorbent article 1 is in a pants-type state, the upper end (17ef) of the crotch elastic member 17 on the ventral side is located lower than the lower end (2ed) of the side joint 2. Since the range (effective length range) over which the stretchability of the crotch elastic member 17 acts is shorter on the front side (ventral side) than on the rear side (dorsal side), the force pushing the absorbent core 11 toward the skin is less likely to be excessively large, and the absorbent core 11 is less likely to be pressed strongly against the wearer's urethral opening or vaginal opening. This prevents the absorbent core 11 from feeling uncomfortable, such as pain, due to excessive adhesion of the absorbent core 11 to the excretory opening, improving the comfort of the absorbent article 1.

[0072] Furthermore, in the longitudinal direction of the absorbent article 1 in the unfolded and stretched state, the front ends 17ef of the crotch elastic members 17 are located forward of the center position (first center line CL1), and the front ends (lower ends) 30Bd of the extension portions 30B of the rear waistband member 30 are located rearward of the center position (first center line CL1). Since the crotch elastic members 17 extend forward of the longitudinal center position, i.e., forward of the crotch portion when worn, the absorbent core 11 can be securely fitted in the rear region of the vaginal opening. Meanwhile, since the front ends (lower ends) 30Bd of the extension portions 30B, which function as buttocks covers, are located rearward of the longitudinal center position, i.e., rearward and above the crotch portion when worn, the buttocks covers are prevented from interfering with leg movement or causing discomfort when walking, etc., thereby further improving the fit and feel of the absorbent article 1.

[0073] The absorbent article 1 is folded from a pants-like state in the left-right and up-down directions to a compact shape, packaged in a predetermined packaging material, and distributed to the market. Figures 6A and 6B are diagrams illustrating an example of a method for folding the absorbent article 1. Figures 6A and 6B illustrate a case where the absorbent article 1 is folded in thirds in the left-right direction.

[0074] First, with respect to the pants-type absorbent article 1 in its natural state, as shown in FIG. 6A , an end region of the absorbent article 1 is folded from the outside (right side) to the inside (left side) in the left-right direction at a folding position FL1 located to the right of the absorbent main body 10 in the left-right direction. Similarly, an end region of the absorbent article 1 is folded from the outside (left side) to the inside (right side) in the left-right direction at a folding position FL2 located to the left of the absorbent main body 10 in the left-right direction. This results in the absorbent article 1 folded in three as shown in FIG. 6B . The absorbent article 1 in the three-fold state has folding positions FL1 and FL2 as folding lines, and is smaller in length (width) in the left-right direction compared to the natural state (pants-type state) of FIG. 6A , resulting in a more compact state. Note that the absorbent article 1 may be further folded longitudinally from the state shown in FIG. 6B to a more compact state.

[0075] In the absorbent article 1, the waist elastic members 23, 33 are arranged across the folding lines (folding positions) FL1, FL2 in the left-right direction. That is, the elastic force of the waist elastic members 23, 33 is easily exerted at positions FL1, FL2 where the absorbent article 1 is folded in thirds in the left-right direction. This makes it possible to prevent the absorbent main body 10 from being deformed by external forces or the like during distribution. For example, when the absorbent article 1 is packaged and distributed in the state shown in FIG. 6B , if it is subjected to a compressive force (external force) from the outside to the inside in the left-right direction, the external force is alleviated by the elastic force of the waist elastic members 23, 33 acting at the folding positions FL1, FL2, making it easier to prevent the absorbent main body 10 from being deformed.

[0076] Similarly, in the absorbent article 1, the crotch elastic members 17 are arranged across a central position CL1 in the longitudinal direction (corresponding to the folding line along which the absorbent main body 10 is folded in half in the longitudinal direction). That is, the elastic force of the crotch elastic members 17 is easily exerted at the central position CL1 where the absorbent article 1 is folded in the longitudinal direction. This makes it possible to prevent the absorbent main body 10 from being deformed by external forces or the like during distribution. For example, when the absorbent main body 10 is subjected to a compressive force (external force) from the outside to the inside in the longitudinal direction (vertical direction), the external force is alleviated by the elastic force of the crotch elastic members 17 acting at the central position CL1, making it easier to prevent deformation of the absorbent main body 10.

[0077] This makes it easier to maintain the folded state (packaged state) of the absorbent article 1, and also prevents the absorbent main body 10 from being deformed during distribution.

[0078] Furthermore, the rear waistline member 30 of the absorbent article 1 is provided with a post-treatment tape 60 that is used when disposing of the absorbent article 1 after use. The post-treatment tape 60 is a tape-like member (tape member) that is elongated in the up-down direction (vertical direction), and is made of a resin material such as polyethylene or polypropylene. In the absorbent article 1, as shown in Figures 2 and 3 , the post-treatment tape 60 is provided on the non-skin side of the rear waistline member 30 (the non-skin side of the non-skin side sheet 32). One vertical side of the post-treatment tape 60 is fixed to the rear waistline member 30, and the other vertical side has an adhesive portion. An adhesive is applied to the adhesive portion, and before use of the absorbent article 1, a portion of the post-treatment tape 60 is folded with the adhesive portion facing inward, thereby protecting the adhesive surface and preventing the adhesive portion from being exposed to the outside.

[0079] 7A and 7B are diagrams illustrating how to use the post-treatment tape 60. When disposing of the absorbent article 1 after use, the folded post-treatment tape 60 is stretched and pulled as shown in FIG. 7A to extend the adhesive portion so that the adhesive portion is exposed. Next, the absorbent article 1 is rolled up vertically so that the absorbent main body 10 is on the inside, and the adhesive portion side of the post-treatment tape 60 is wrapped around the absorbent article 1 as shown in FIG. 7B. This makes it possible to maintain the absorbent article 1 in a rolled state, and the absorbent article 1 can be disposed of without leaking excrement and the like adhering to the inside (absorbent main body 10) of the absorbent article 1 to the outside.

[0080] In the absorbent article 1 of this embodiment, the post-processing tape 60 is arranged so as to be inclined at a predetermined angle with respect to the longitudinal direction. In other words, the post-processing tape 60 is arranged so that the angle between the longitudinal direction of the post-processing tape 60 and the longitudinal direction of the absorbent main body 10 (the vertical direction of the absorbent article 1) is greater than 0 degrees. In Fig. 7A , the post-processing tape 60 is arranged so as to be inclined at an angle θ1 with respect to the vertical direction (longitudinal direction). By arranging the post-processing tape 60 at an angle in this manner, when the absorbent article 1 is rolled up and discarded after use as shown in Fig. 7B , the area fixed by the post-processing tape 60 is wider in the left-right direction compared to when the post-processing tape 60 is arranged parallel to the vertical direction, making it easier to maintain the rolled state of the absorbent article 1. Furthermore, when wrapping the post-treatment tape 60 around the absorbent article 1 while pulling it in the vertical direction (longitudinal direction), the wrapping operation is easier to perform by utilizing the stretching force of the crotch elastic members 17 along the longitudinal direction, and the wrapped state is more easily maintained, compared to when the post-treatment tape 60 is arranged parallel to the left-right direction. Therefore, the operation of disposing of the absorbent article 1 can be made easier.

[0081] Second Embodiment In the second embodiment, an absorbent article 1 will be described in which the attachment method of at least some of the waistline elastic members 23, 33 and the extension portion elastic members 35 provided on the waistline members 20, 30 is different. In the absorbent article 1 of the second embodiment, the configuration other than the attachment method of the elastic members 23, 33, 35 is the same as (the same configuration as) the absorbent article 1 described in the first embodiment, and therefore a description of the configuration of the common parts will be omitted.

[0082] In the absorbent article 1 of the first embodiment, the skin-side sheet 21 (31) and the non-skin-side sheet 22 (32) constituting the waistband member 20 (30) are joined in the thickness direction via an adhesive applied to the waistband elastic member 23 (33), and waistband elastic members 23 (33, 35) are attached between the skin-side sheet 21 (31) and the non-skin-side sheet 22 (32). In contrast, in the absorbent article 1 of the second embodiment, the skin-side sheet 21 (31) and the non-skin-side sheet 22 (32) are joined by a plurality of scattered welded portions 50, 50..., and waistband elastic members 23 (33, 35) are attached.

[0083] The following describes an example in which the extension-portion elastic members 35 are attached to the extension portions 30B of the rear waistline member 30 by forming the welded portions 50. Fig. 8 is a diagram illustrating an example of the arrangement of the welded portions 50 in the extension portions 30B of the rear waistline member 30. Figs. 9A and 9B are diagrams illustrating the principle by which the extension-portion elastic members 35 are attached to the extension portions 30B by the welded portions 50.

[0084] In the extension portion 30B (rear waistline member 30) of the absorbent article 1, the skin side sheet 31 and the non-skin side sheet 32 ​​are joined together by a plurality of welded portions 50, 50... formed using a known welding means such as ultrasonic welding. Note that at the stage of forming the welded portions 50, the rear waistline member 30 and the absorbent main body 10 are not yet joined together.

[0085] 8, the extension-portion elastic member 35 is sandwiched between two vertically adjacent welded portions 50, 50 out of the multiple welded portions 50, 50, thereby attaching the extension-portion elastic member 35 to the extension portion 30B. That is, a pair of welded portions 50, 50 aligned on both sides of the extension-portion elastic member 35 in the vertical direction form a welded portion pair 50s, and the extension-portion elastic member 35 is attached by the welded portion pair 50s. Note that, although Fig. 8 shows the welded portions 50, 50 (welded portion pair 50s) only at positions where the extension-portion elastic member 35 is sandwiched between the extension-portion elastic member 35 in the vertical direction, the welded portions 50 may be provided in positions that are not adjacent to the extension-portion elastic member 35 in the vertical direction.

[0086] 9A , a pair of welded portions 50, 50 constituting a welded portion pair 50s are arranged vertically with a gap GH50 therebetween. The gap GH50 is set to be equal to or slightly larger than the outer diameter D35t of the extension-portion elastic member 35, such as a rubber thread, when stretched laterally to the target elongation ratio (GH50≧outer diameter D35t). In other words, the extension-portion elastic member 35 in a stretched state is positioned vertically between the welded portion pair 50s. With this configuration, during the manufacturing process of the absorbent article 1, the extension-portion elastic member 35 in a stretched state is positioned between the skin-side sheet 31 and the non-skin-side sheet 32, and then the welded portion 50 can be formed without overlapping with the extension-portion elastic member 35 when the skin-side sheet 31 and the non-skin-side sheet 32 ​​are joined together. Here, the "extension ratio" refers to a value R (=L1 / L0) that indicates how many times the total length L1 of the extension elastic member 35 is extended relative to the total length L0 in the unloaded state, which is the natural length.

[0087] 9A , when the extension-portion elastic member 35 is relaxed from its stretched state, as shown in FIG. 9B , the waistline extension-portion elastic member 35 contracts left and right while expanding up and down, and the expanded outer diameter D35t' becomes larger than the vertical distance GH50 between the pair of welded portions 50s (D35t' > GH50). Therefore, the vertical expansion of the extension-portion elastic member 35 is restricted between the pair of welded portions 50s, and the extension-portion elastic member 35 is essentially sandwiched between the welded portions 50, 50 in the vertical direction. As a result, the pair of welded portions 50s restricts the vertical and horizontal positions of the extension-portion elastic member 35, and the extension-portion elastic member 35 is stretchably attached to the extension portion 30B, allowing it to exhibit stretchability in the horizontal direction. The extension-portion elastic member 35 exhibits stretchability in a region between the pair of welded portions 50s located on one side (outer side) and the pair of welded portions 50s located on the other side (inner side) in the left-right direction. For example, in the left-right direction in Fig. 8, the extension-portion elastic member 35 exhibits stretchability in a region between the pair of welded portions 50s (the innermost pair of welded portions 50s) located at the left end BCL of the central non-stretchable portion BCN and the pair of welded portions 50s (the outermost pair of welded portions 50s) located closest to the edge 30Be of the extension portion 30B.

[0088] FIG. 10 illustrates the arrangement of the extension-portion elastic member 35 and the welded portion pair 50s at the left and right ends of the extension portion 30B. As described above, the extension-portion elastic member 35 exhibits stretchability in a region inward of the outermost welded portion pair 50s (the welded portion pair 50sa in FIG. 10 ) in the left and right direction. That is, the position of the outer end 35eo of the extension-portion elastic member 35 in the left and right direction is determined by the outermost welded portion pair 50sa. The welded portion pair 50sa is located a predetermined distance inward in the left and right direction from the edge 30Be of the extension portion 30B. This is because the edge 30Be of the extension portion 30B is curved as shown in FIG. 10 , making it difficult to form the welded portion pair 50s that sandwiches the extension-portion elastic member 35 above and below at a position overlapping the edge 30Be. As a result, the extension-portion elastic member 35 is discontinuous in the left-right direction between the outer end 35e0 of the extension-portion elastic member 35 and the edge 30Be of the extension portion 30B, forming a side-end non-stretchable portion BSN where no stretching force is applied. In Figure 10, a side-end non-stretchable portion BSN with a width L3' is formed on an imaginary extension line of the extension-portion elastic member 35.

[0089] In the absorbent article 1 of the second embodiment, a pair of welded portions 50sa is provided at a position spaced apart in the left-right direction from the edge 30Be of the extension portion 30B, and the extension-portion elastic member 35 is stably fixed by the pair of welded portions 50sa, which makes it easier to prevent the side-end non-stretchable portions BSN from widening further. That is, the extension-portion elastic member 35 is prevented from shrinking to the left-right inner side of the pair of welded portions 50sa (so-called rubber loss). Therefore, the side-end non-stretchable portions BSN are less likely to become excessively large, making it easier to maintain a good fit and feel against the skin for a long time when wearing the absorbent article 1.

[0090] ===Other=== The above embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The present invention may be modified or improved without departing from the spirit thereof, and it goes without saying that the present invention includes equivalents thereof.

[0091] Although an absorbent article has been illustrated as an embodiment of the present invention, disposable diapers, particularly for children or adults, may require space to store feces, and since the absorbent article 1 in the above embodiment is configured without a space for storing feces in the rear portion, it is preferably applied to a shorts-type sanitary napkin. Furthermore, the pants-type absorbent article in the above embodiment is preferably applied to a shorts-type napkin because it can be suitably applied to preventing menstrual blood leakage from the viewpoint of suppressing leakage.

[0092] DESCRIPTION OF SYMBOLS 1 Pants-type absorbent article, 2 Side joint portion, 3 Leakage preventing wall portion, 10 Absorbent main body, 10F End (front side), 10B End (rear side), 11 Absorbent core, 12 Top sheet, 13 Back sheet, 14 Sheet member, 15 Core wrap sheet, 16 Leakage preventing wall elastic member, 17 Crotch elastic member, 17ef End (front side), 17eb End (rear side), 18 Leg opening elastic member, 20 Front waistline member, 21 Skin side sheet, 22 Non-skin side sheet, 23 Front waistline elastic member, 30 Rear waistline member, 30A Waist side portion, 30B Extension portion (buttocks cover), 30Be Edge, 31 Skin side sheet, 32 Non-skin side sheet, 33 Rear waistline elastic member, 35 Extension elastic member, 50 welded portion, 50s pair of welded portions, 50sa pair of welded portions (outer end portion), 60 post-treatment tape, BH waist opening, LH leg opening, CL1 first center line (longitudinal direction), CC1 second center line (left-right direction), FCN central non-stretchable portion (front waist central non-stretchable portion), BCN central non-stretchable portion (rear waist central non-stretchable portion), BSN side end non-stretchable portion

Claims

1. A pants-type absorbent article having a vertical direction, a horizontal direction, and a front-to-back direction that intersect with each other, comprising an absorbent main body having an absorbent core, a front waistline member, and a rear waistline member, the front waistline member and the rear waistline member being joined in a ring shape by a pair of side joints, the article having a crotch elastic member that stretches along the longitudinal direction of the absorbent main body at a central portion in the horizontal direction and closer to the skin than the absorbent core, at least one of the front waistline member and the rear waistline member having an extension portion that extends downward in the vertical direction beyond the lower end of the side joint, the extension portion having an extension portion elastic member that is linearly arranged along the horizontal direction, the extension portion having a central non-stretchable portion where the extension portion elastic member is discontinuous at the horizontal central portion and where no stretching force acts, and side end non-stretchable portions where the extension portion elastic member is discontinuous at the side end portions in the horizontal direction and where no stretching force acts When the pants-type absorbent article is in an unfolded and stretched state, in the left-right direction, the length of the central non-stretchable portion on an imaginary extension line of the extension portion elastic member is longer than the length from the most one end to the most other end of the portion where the crotch elastic member is provided, and the length of the central non-stretchable portion on the imaginary extension line is longer than the length of the side end non-stretchable portions on the imaginary extension line.

2. A pants-type absorbent article as described in claim 1, characterized in that the extension portion has a skin-side sheet arranged closer to the skin than the extension portion elastic member and a non-skin-side sheet arranged less close to the skin than the extension portion elastic member, and the non-stretchable side end portion on the virtual extension line has a portion where the skin-side sheet and the non-skin-side sheet are joined to each other.

3. A pants-type absorbent article according to claim 1, wherein the extension portion comprises a skin-side sheet arranged closer to the skin than the extension-portion elastic member and a non-skin-side sheet arranged closer to the skin than the extension-portion elastic member, the skin-side sheet and the non-skin-side sheet being joined together by a plurality of scattered welds, the spacing between a pair of adjacent welds in the vertical direction is smaller than the diameter of the extension-portion elastic member in its natural state, and the position of the extension-portion elastic member in the vertical direction is restricted by being sandwiched between the pair of welds, and the pair of welds located outermost in the left-right direction on the imaginary extension line are arranged at a position spaced a predetermined distance inward from the outer end of the extension portion.

4. A pants-type absorbent article according to any one of claims 1 to 3, characterized in that the distance on the imaginary extension line, in the left-right direction, between the most one end of the portion where the crotch elastic member is provided and one end of the central non-stretchable portion is longer than the length of the side end non-stretchable portion.

5. A pants-type absorbent article according to any one of claims 1 to 3, characterized in that, on the imaginary extension line, in the left-right direction, one end of the central non-elastic part is located to one side of one end of the absorbent core.

6. A pants-type absorbent article as described in claim 5, characterized in that, on the imaginary extension line, in the left-right direction, one end of the central non-elastic part is located on the other side of one end of the absorbent main body.

7. A pants-type absorbent article according to any one of claims 1 to 3, characterized in that the extension portion is provided on the rear waistband member and not on the front waistband member.

8. A pants-type absorbent article as claimed in claim 7, characterized in that in an unfolded and stretched state, it has a longitudinal direction and a left-right direction which are perpendicular to each other, the crotch elastic members are continuous along the longitudinal direction, and in the longitudinal direction, the rear end of the crotch elastic members is located rearward of the front end of the side joint portion provided on the rear waistband member.

9. A pants-type absorbent article as claimed in claim 7, wherein the rear waistband member has a rear waistband elastic member that stretches in the left-right direction, the rear waistband member has a rear waistband central non-stretchable portion in the left-right central portion where the rear waistband elastic member is discontinuous and no stretching force acts, and the length of the rear waistband central non-stretchable portion on an imaginary extension line of the rear waistband elastic member is longer than the length in the left-right direction from the extreme one end to the extreme other end of the portion where the crotch elastic member is provided.

10. A pants-type absorbent article according to any one of claims 1 to 3, characterized in that in an unfolded and stretched state, it has a longitudinal direction and a left-right direction which are perpendicular to each other, and in the longitudinal direction, the front end of the crotch elastic member is located further rearward than the rear end of the front waistband member.

11. A pants-type absorbent article as claimed in claim 10, characterized in that, in the longitudinal direction, the front end of the crotch elastic member is located forward of the central position of the pants-type absorbent article, and the front end of the extension portion provided on the rear waistband member is located rearward of the central position.

12. A pants-type absorbent article according to claim 10, wherein the front waistband member and the rear waistband member each have waistband elastic members that stretch along the left-right direction, and have fold lines on both sides in the left-right direction that fold the pants-type absorbent article in thirds in the left-right direction, the waistband elastic members are arranged across the fold lines in the left-right direction, and the crotch elastic members are arranged across the center position of the pants-type absorbent article in the longitudinal direction.

13. A pants-type absorbent article as set forth in any one of claims 1 to 3, characterized in that a post-treatment tape is provided on the non-skin side of the rear waistband member to be used when disposing of the pants-type absorbent article after use, and the angle formed between the longitudinal direction of the post-treatment tape and the longitudinal direction of the absorbent main body is greater than 0 degrees.

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