Underpants type absorbent article

Abstract

To provide an underpants type absorbent article which has a proper surface pressure and has a leg gathering which is hardly turned to inside.SOLUTION: An underpants type absorbent article (1) comprises: an absorbent body (10); and a pair of leg gathering parts (LG), where the leg gathering part (LG) has: three or more leg gathering elastic members (17) which extend and shrink in a longitudinal direction and arranged at an interval of 5 mm or more in a lateral direction. The shrinkage force of the first leg gathering elastic member (17a) is greater than that of the second leg gathering elastic members (17b, 17c) which are arranged outside of the lateral direction. In the leg gathering part (LG), in an area (ER) from the outermost end (10es) in the lateral direction to the leg gathering elastic member (17a) which is arranged at innermost side, rigidity application means is provided. At least part of the rigidity application means does not overlap to the leg gathering elastic member (17) and is continuous to the longitudinal direction.SELECTED DRAWING: Figure 6

Description

Technical Field

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

Background Art

[0002] Conventionally, in pant-type diapers and the like provided with leg gathers (LG) that can stretch along the leg openings, a technique has been known in which by widening the width of the leg gathers, the fitting property of the leg cuffs is improved while suppressing lateral leakage of excrement such as urine. For example, Patent Document 1 discloses a pant-type diaper provided with a pair of extending portions (corresponding to leg gathers) extending from both side edges of an absorber to both outer sides in the width direction, and by making the length of the extending portion in the width direction larger than the height of the leak-proof cuff portion, it is possible to fit the extending portion (leg gather) widely around the legs of the wearer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the pant-type disposable diaper of Patent Document 1, a plurality of leg elastic members that stretch along the longitudinal direction (the longitudinal direction of the absorber) are provided in the leg gather portion to impart elasticity to the leg gather portion. However, if a large number of leg elastic members are provided at narrow intervals in the leg gather portion, the surface pressure of the leg gather portion may become high, which may cause a constriction or redness on the leg cuffs of the wearer. Conversely, if the number of leg elastic members provided in the leg gather portion is small, the wide leg gather portion is likely to be wrinkled inward (the crotch side), which may deteriorate the fitting property or cause uneasiness about leakage.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a pant-type absorbent article having a leg gather that is not overly high in surface pressure and is difficult to wrinkle inward.

Means for Solving the Problems

[0006] The main invention for achieving the above object has a vertical direction and a horizontal direction that intersect each other, and has an absorbent body, a front body circumference portion, and a rear body circumference portion. The front body circumference portion and the rear body circumference portion are joined to each other by a pair of side joining portions at both ends in the horizontal direction. On both sides of the absorbent body in the horizontal direction, a pair of leak-proof wall portions and leg gather portions are provided respectively. In the leg gather portion, three or more leg gather elastic members that stretch along the longitudinal direction of the absorbent body are arranged at intervals of 5 mm or more in the horizontal direction. The pant-type absorbent article is such that the leg gather elastic member has a first leg gather elastic member and a second leg gather elastic member arranged outside the first leg gather elastic member in the horizontal direction. The contraction force of the first leg gather elastic member when it is extended to 0.9 times its length when the first leg gather elastic member is extended along the longitudinal direction and then returned to 0.7 times its length is greater than the contraction force of the second leg gather elastic member when the second leg gather elastic member is extended to 0.9 times its length when the second leg gather elastic member is extended along the longitudinal direction and then returned to 0.7 times its length. In the region of the leg gather portion from the outermost end in the horizontal direction to the innermost arranged leg gather elastic member, there is a rigidity imparting means for imparting rigidity to the leg gather portion. At least a part of the rigidity imparting means does not overlap with the leg gather elastic member when viewed in the thickness direction, and has a portion continuous in the longitudinal direction in a region below the lower end of the side joining portion. This is a pant-type absorbent article characterized by the above. Other features of the present invention will be clarified by the description in this specification and the accompanying drawings.

Effects of the Invention

[0007] According to the present invention, it is possible to provide a pant-type absorbent article having a leg gather that does not have an excessively high surface pressure and is difficult to wrinkle inward.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

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Figure 6

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Figure 10

Figure 11

Mode for Carrying Out the Invention

[0009] From the description of this specification and the accompanying drawings, at least the following matters become clear.

[0010] (Aspect 1) A pants-type absorbent article having a vertical direction and a horizontal direction that intersect each other, an absorbent body, a front body waist portion, and a rear body waist portion, wherein the front body waist portion and the rear body waist portion are joined to each other by a pair of side joining portions at both ends in the horizontal direction, and a pair of leak-proof wall portions and a pair of leg gather portions are provided on both sides of the absorbent body in the horizontal direction, respectively. In the leg gather portion, three or more leg gather elastic members that expand and contract along the longitudinal direction of the absorbent body are arranged at intervals of 5 mm or more in the horizontal direction. The leg gather elastic member has a first leg gather elastic member and a second leg gather elastic member arranged outside the first leg gather elastic member in the horizontal direction. When the first leg gather elastic member is extended to 0.9 times its length when extended most along the longitudinal direction and then retracted to 0.7 times its length, the contraction force of the first leg gather elastic member is greater than the contraction force of the second leg gather elastic member when the second leg gather elastic member is extended to 0.9 times its length when extended most along the longitudinal direction and then retracted to 0.7 times its length. In the region of the leg gather portion from the outermost end in the horizontal direction to the innermost arranged leg gather elastic member, there is a rigidity imparting means for imparting rigidity to the leg gather portion. At least a part of the rigidity imparting means does not overlap with the leg gather elastic member when viewed in the thickness direction, and has a portion continuous in the longitudinal direction in a region below the lower end of the side joining portion.

[0011] According to the pant-type absorbent article of Aspect 1, while widening the pitch of the LG elastic members and making the contraction force of the LG elastic members arranged on the outer side in the left-right direction weaker than that on the inner side, when worn, the leg gather part can easily follow the movement of the wearer's legs and fit well. Further, the rigidity is increased over a wide range of the leg gather part by the rigidity imparting means, and the leg gather part can easily maintain its planar shape. As a result, a pant-type absorbent article having a leg gather part with a not-too-high surface pressure and difficult to wrinkle inward is realized. Also, the leg gather part can easily fit the wearer's legs in a planar manner, and it is possible to make it difficult for the user to be reminded of the anxiety such as lateral leakage of excrement.

[0012] (Aspect 2) Among the two leg gather elastic members arranged adjacent to each other in the left-right direction, the contraction force when the leg gather elastic member arranged on the inner side in the left-right direction is extended to 0.9 times the length when it is extended most along the longitudinal direction and then returned to 0.7 times the length is greater than or equal to the contraction force when the leg gather elastic member arranged on the outer side in the left-right direction is extended to 0.9 times the length when it is extended most along the longitudinal direction and then returned to 0.7 times the length. The pant-type absorbent article according to Aspect 1.

[0013] According to the pant-type absorbent article of Aspect 2, since the contraction force of the LG elastic members gradually decreases from the inner side to the outer side in the left-right direction, the leg gather part can easily follow the movement of the wearer's legs and is also easily suppressed from wrinkling. Therefore, it is possible to enhance the fitting property along the leg bending shape of the wearer while suppressing the surface pressure of the leg gather part from becoming excessively high.

[0014] (Aspect 3) Of the two leg gather elastic members arranged adjacent to each other in the left - right direction, for the leg gather elastic member arranged on the inner side in the left - right direction, the value obtained by dividing the length in the natural state by the length when it is stretched most along the longitudinal direction is less than or equal to the value obtained by dividing the length in the natural state by the length when it is stretched most along the longitudinal direction for the leg gather elastic member arranged on the outer side in the left - right direction. The pant - type absorbent article according to Aspect 1 or 2.

[0015] According to the pant - type absorbent article of Aspect 3, the rate of contraction (contraction rate) of the LG elastic member gradually decreases from the inner side to the outer side in the left - right direction, the leg gather portion is more likely to follow the movement of the wearer's legs, and wrinkles are also more likely to be suppressed. Therefore, while suppressing the surface pressure of the leg gather portion from becoming excessively high, the fit can be improved along the leg - folding shape of the wearer.

[0016] (Aspect 4) Of the two leg gather elastic members arranged adjacent to each other in the left - right direction, the cross - sectional area of the leg gather elastic member arranged on the inner side in the left - right direction in the natural state is greater than or equal to the cross - sectional area of the leg gather elastic member arranged on the outer side in the left - right direction in the natural state. The pant - type absorbent article according to any one of Aspects 1 to 3.

[0017] According to the pant - type absorbent article of Aspect 4, usually, the larger the cross - sectional area of the LG elastic member, the larger the diameter of the LG elastic member. Therefore, it is easier to suppress the increase in pressure per unit area on the inner side in the left - right direction of the leg gather portion. Thus, even if the contraction force of the LG elastic member is increased on the inner side in the left - right direction of the leg gather portion, it is suppressed that the surface pressure becomes excessively high, and it is easy to suppress the formation of linear marks on the wearer's skin due to the LG elastic member.

[0018] (Aspect 5) When the region from the outermost end of the leg gather portion to the innermost leg gather elastic member in the left-right direction is defined as the leg gather elastic region, the length of the leg gather elastic region in the left-right direction in the extended state is at least half of the length of the leg gather portion in the left-right direction in the extended state. When the leg gather elastic region is evenly divided in the left-right direction by the number of leg gather elastic members arranged in the leg gather elastic region, each divided region has a leg gather elastic member arranged therein. The pant-type absorbent article according to any one of Aspects 1 to 4.

[0019] According to the pant-type absorbent article of Aspect 5, since the LG elastic members are evenly arranged in the leg gather portion, it is difficult for a local rigidity difference to occur, and it is easy to maintain the surface shape. In addition, since local pressure is less likely to be applied to the wearer's leg crotch portion, it is possible to suppress skin chafing and redness.

[0020] (Aspect 6) The pant-type absorbent article according to any one of Aspects 1 to 5, wherein the rigidity imparting means is provided in each region obtained by evenly dividing the leg gather elastic region in the left-right direction.

[0021] According to the pant-type absorbent article of Aspect 6, in the leg gather elastic region, since the rigidity is increased for each region where the contracting force of the LG elastic member acts, the puckering etc. of the leg gather portion is suppressed, and it becomes easier to maintain the surface shape.

[0022] (Aspect 7) The pant-type absorbent article according to any one of Aspects 1 to 6, wherein the rigidity imparting means is provided between two leg gather elastic members arranged adjacent to each other in the left-right direction when viewed in the thickness direction.

[0023] According to the pant-type absorbent article of Aspect 7, by increasing the rigidity in the region between two adjacent LG elastic members by the rigidity imparting means, it becomes difficult to form a bending starting point between the LG elastic members, so that the gathering of the leg gather portion is more easily suppressed.

[0024] (Aspect 8) The value obtained by dividing the contraction force when the leg gather portion is extended to 0.9 times the length when it is most extended along the longitudinal direction and then returned to 0.7 times the length by the width of the leg gather portion is the same as the value obtained by dividing the contraction force when the leakage-preventing wall portion is extended to 0.9 times the length when it is most extended along the longitudinal direction and then returned to 0.7 times the length by the width of the leakage-preventing wall portion. The pant-type absorbent article according to any one of Aspects 1 to 7, provided with the rigidity imparting means, is not more than this value.

[0025] According to the pant-type absorbent article of Aspect 8, since the surface pressure of the leg gather portion becomes relatively small as compared with the case where the contraction force per unit width of the leg gather portion is larger than the contraction force per unit width of the leakage-preventing wall, it is possible to make it difficult to cause blisters or redness on the wearer's leg cuffs during wearing.

[0026] (Aspect 9) The leg gather portion has at least two sheet members laminated in the thickness direction, and a leg gather elastic member is provided between the laminated sheet members. The rigidity imparting means imparts rigidity to the leg gather portion by joining the laminated sheet members to each other. The pant-type absorbent article according to any one of Aspects 1 to 8.

[0027] According to the pant-type absorbent article of Aspect 9, In the leg gather portion, the sheet members laminated in the thickness direction are joined to each other, thereby enhancing the rigidity and making it easier to maintain the sheet members constituting the leg gather portion in a planar shape. As a result, it becomes difficult for the leg gather portion to wrinkle. Further, since the joint portion itself (for example, a welded portion or an adhesive portion) has rigidity, it becomes easier to ensure the rigidity of the leg gather portion.

[0028] (Aspect 10) The rigidity-imparting means imparts rigidity to the leg gather portion by joining the laminated sheet members to each other with an adhesive, and is the pant-type absorbent article according to any one of Aspects 1 to 9.

[0029] According to the pant-type absorbent article of Aspect 10, the rigidity of the leg gather portion is enhanced, the sheet members constituting the leg gather portion are easily maintained in a planar shape, and it becomes difficult for the leg gather portion to wrinkle. Further, since an adhesive such as a hot melt adhesive is solidified at normal temperature, the adhesive itself has rigidity, and it becomes easier to ensure the rigidity of the leg gather portion.

[0030] (Aspect 11) When the region from the outermost end of the leg gather portion in the extended state to the leg gather elastic member disposed most inwardly in the left-right direction is defined as the leg gather elastic region, the rigidity-imparting means is provided in an area of at least half of the leg gather elastic region, and is the pant-type absorbent article according to any one of Aspects 1 to 10.

[0031] According to the pant-type absorbent article of Aspect 11, since more than half of the leg gather elastic region is enhanced in rigidity by the rigidity-imparting means, the leg gather elastic region is easily maintained in a planar shape, and it is easy to suppress the occurrence of wrinkles in the leg gather portion.

[0032] (Aspect 12) The absorbent body has a liquid-absorbent absorber, and a liquid-impermeable sheet is provided on the non-skin side of the absorber. In the left-right direction, the outer end of the liquid-impermeable sheet is located between the outermost leg gather elastic member and the second outermost leg gather elastic member. The pant-type absorbent article according to any one of Aspects 1 to 11.

[0033] According to the pant-type absorbent article of Aspect 12, since the leak-proof film is provided up to the vicinity of the tip of the leg gather portion, the rigidity of the leg gather portion is increased as compared with the case where there is no leak-proof film, and it is easy to maintain the surface shape. Further, since no leak-proof film is provided outside the outermost LG elastic member, the tip edge of the leg gather portion is less likely to become hard, and even when the tip edge contacts the wearer's skin, it is difficult to cause a sense of discomfort or discomfort to the wearer.

[0034] (Aspect 13) In the left-right direction, the rigidity imparting means is not provided outside the outermost leg gather elastic member. The pant-type absorbent article according to any one of Aspects 1 to 12.

[0035] According to the pant-type absorbent article of Aspect 13, the rigidity of the tip edge of the leg gather portion is not excessively increased, and flexibility is maintained. Therefore, even when the tip edge contacts the wearer's skin during wearing, it is difficult to cause a sense of discomfort or discomfort to the wearer.

[0036] (Aspect 14) The shortest distance from the outer end in the left-right direction of the leg gather portion in the extended state to the standing start point of the leak-proof wall portion is equal to or greater than the shortest distance from the standing start point of the leak-proof wall portion to the tip portion of the leak-proof wall portion in the extended state. The pant-type absorbent article according to any one of Aspects 1 to 13.

[0037] According to the pant-type absorbent article of Aspect 14, even if the leak-preventing wall portion falls outward in the left-right direction from the standing state during wearing, it is suppressed that the fallen leak-preventing wall portion protrudes outward beyond the tip of the leg gather portion. Therefore, it is difficult to form a gap between the leg gather portion and the wearer's skin, and it is possible to easily fit the leg gather portion to the wearer's leg bend in a planar manner.

[0038] (Aspect 15) The absorbent main body has a liquid-absorbent absorber, and in the left-right direction, in the region between the outer end of the absorber and the standing start point of the leak-preventing wall portion, there is a crotch elastic member that stretches along the longitudinal direction of the absorbent main body. The pant-type absorbent article according to any one of Aspects 1 to 14.

[0039] According to the pant-type absorbent article of Aspect 15, during wearing, both outer sides of the absorber in the left-right direction are pushed upward toward the skin side by the elasticity exhibited by the crotch elastic member, so that the absorber easily fits to the crotch portion of the wearer. Further, since the root side of the leg gather portion is pushed upward toward the skin side by the elasticity of the crotch elastic member, it becomes easier to fit the leg gather portion to the wearer's skin.

[0040] (Aspect 16) The absorbent main body has a liquid-absorbent absorber, and a topsheet is provided on the skin side of the absorber. At least a part of the topsheet is disposed outside the standing start point of the leak-preventing wall portion in the left-right direction. The pant-type absorbent article according to any one of Aspects 1 to 15.

[0041] According to the pant-type absorbent article of Aspect 16, the portion of the topsheet disposed outside the standing start point functions as a rigidity-imparting means for imparting rigidity to the leg gather portion, so that the leg gather portion easily maintains a planar shape and is less likely to wrinkle. As a result, it is difficult to form a gap between the leg gather portion and the wearer's skin during wearing, and the leg gather portion easily fits to the leg bend in a planar manner.

[0042] (Aspect 17) The front torso surrounding portion and the rear torso surrounding portion have a torso elastic member that expands and contracts in the left-right direction, and when viewed in the thickness direction, at least one of the front torso surrounding portion and the rear torso surrounding portion has a portion where the torso elastic member and the leg gather elastic member intersect. The pant-type absorbent article according to any one of Aspects 1 to 16.

[0043] According to the pant-type absorbent article of Aspect 17, since the contraction force of the torso elastic member and the contraction force of the LG elastic member are interlocked, the LG elastic member is easily pulled upward, so that the whole pant-type absorbent article is less likely to hang downward, and deterioration of the fit of the torso surrounding portion and the leg gather portion is suppressed.

[0044] (Aspect 18) A pants-type absorbent article having a vertical direction and a horizontal direction that intersect each other, an absorbent body, a front body circumferential portion, and a rear body circumferential portion, wherein the front body circumferential portion and the rear body circumferential portion are joined to each other by a pair of side joining portions at both end portions in the horizontal direction, and a pair of leak-proof wall portions and a pair of leg gather portions are provided on both sides of the absorbent body in the horizontal direction, respectively. In the leg gather portion, three or more leg gather elastic members that stretch along the longitudinal direction of the absorbent body are arranged at intervals of 5 mm or more in the horizontal direction. The leg gather elastic member has a first leg gather elastic member and a second leg gather elastic member arranged outside the first leg gather elastic member in the horizontal direction. The contraction force of the first leg gather elastic member when it is extended to 0.9 times its length when the first leg gather elastic member is extended along the longitudinal direction and then returned to 0.7 times its length is greater than the contraction force of the second leg gather elastic member when the second leg gather elastic member is extended to 0.9 times its length when the second leg gather elastic member is extended along the longitudinal direction and then returned to 0.7 times its length. The front body circumferential portion and the rear body circumferential portion have elasticity along the horizontal direction. When the front body circumferential portion is divided into four equal parts in the vertical direction between the upper end and the lower end of the side joining portion, and the third region from the upper side is the third front body circumferential region and the fourth region from the upper side is the fourth front body circumferential region, the contraction force of the third front body circumferential region when it is extended to 0.9 times its length when extended along the horizontal direction and then returned to 0.7 times its length is greater than the contraction force of the fourth front body circumferential region when the fourth front body circumferential region is extended to 0.9 times its length when extended along the horizontal direction and then returned to 0.7 times its length.

[0045] According to the pant-type absorbent article of Aspect 18, in the front body circumference portion, by increasing the contraction force of the third front body circumference region and the fourth front body circumference region, the fit of the front body circumference portion can be improved. At this time, by making the contraction force of the fourth front body circumference region smaller than the contraction force of the third front body circumference region, the lower end portion of the fourth front body circumference region is less likely to interfere with the movement of the wearer's legs, and the displacement of the front body circumference portion is suppressed. As a result, the fit of the front body circumference portion can be improved without interfering with the movement of the wearer's legs or the movement of the abdomen due to breathing. And, since the fit of the front body circumference portion is improved and displacement is less likely to occur, the wide leg gather portion is more likely to fit snugly around the wearer's calves.

[0046] (Aspect 19) When the front body circumference portion is divided into four equal parts in the vertical direction between the upper end and the lower end of the side joining portion, and the first region from the top is the first front body circumference region and the second region from the top is the second front body circumference region, for each of the first front body circumference region to the fourth front body circumference region, when stretched to 0.9 times the length when stretched most along the left-right direction and then returned to 0.7 times the length, the magnitude of the contraction force is such that the third front body circumference region is the largest, the pant-type absorbent article according to Aspect 18.

[0047] According to the pant-type absorbent article of Aspect 19, the portion where the third front body circumference region abuts during wearing has a small protrusion of the abdomen and small fluctuations due to breathing and the like, so even if the contraction force of the third front body circumference region is increased, it is difficult to cause discomfort to the wearer. And, by firmly fitting the third front body circumference region to the portion with small movement (fluctuation) of the abdomen and fixing the position, the entire front body circumference portion is less likely to shift and fall, and the fit of the front body circumference portion and the leg gather portion can be further improved.

[0048] (Aspect 20) The sum of the contraction forces of the third front body circumference region and the fourth front body circumference region is larger than the sum of the contraction forces of the first front body circumference region and the second front body circumference region, the pant-type absorbent article according to Aspect 18 or 19.

[0049] According to the pant-type absorbent article of Aspect 20, since the upper regions (the first front torso region 20 and the second front torso region) of the front torso portion are located in the portions of the wearer's abdomen where there are large protrusions and fluctuations, if the tightening is excessively strong, it is likely to cause discomfort to the wearer. On the other hand, since the lower regions (the third front torso region and the fourth front torso region) of the front torso portion are located in the portions of the wearer's abdomen where there are small protrusions and fluctuations, by tightening more strongly compared to the upper regions, it is difficult to cause discomfort to the wearer, and the fitting property can be efficiently enhanced. In particular, it is suitable when the wearer is an infant whose abdomen is likely to be concave, because the fitting property can be enhanced while ensuring safety.

[0050] (Aspect 21) When the rear torso portion is equally divided into four in the vertical direction between the upper end and the lower end of the side joining portion, and the first region from the top is the first rear torso region, the second region from the top is the second rear torso region, the third region from the top is the third rear torso region, and the fourth region from the top is the fourth rear torso region, for each of the first rear torso region to the fourth rear torso region, when it is extended to 0.9 times the length when extended most along the left-right direction and then returned to 0.7 times the length, the magnitude of the contraction force, the third rear torso region is the largest, the pant-type absorbent article according to any one of Aspects 18 to 20.

[0051] According to the pant-type absorbent article of Aspect 21, in the region of the wearer's abdomen where the protrusion is small and the fluctuation due to breathing or the like is small, the third front torso region and the third rear torso region that are annularly connected interlock with each other, so that it becomes easy to apply a large contraction force along the torso. Therefore, in this region, the torso portion is less likely to be displaced, and the fitting property can be further improved without causing discomfort to the wearer.

[0052] (Aspect 22) When the rear body circumferential part is equally divided into four parts in the vertical direction between the upper end and the lower end of the side joint part, when the first region from the upper side is the first rear body circumferential region, the second region from the upper side is the second rear body circumferential region, the third region from the upper side is the third rear body circumferential region, and the fourth region from the upper side is the fourth rear body circumferential region, for each of the first rear body circumferential region to the fourth rear body circumferential region, when it is extended to 0.9 times the length when extended most in the left - right direction and then returned to 0.7 times the length, the magnitude of the contraction force is such that the second rear body circumferential region is the largest, the pants - type absorbent article according to any one of aspects 18 to 21.

[0053] According to the pants - type absorbent article of aspect 22, at the wearer's back side, at the part where the constriction becomes large at the boundary between the back and the buttocks, by increasing the contraction force of the second rear body circumferential region, the body circumferential part is easily fixed firmly, slippage is suppressed, and the fit is improved.

[0054] (Aspect 23) In the natural state, the length of the third front body circumferential region in the left - right direction is shorter than the length of the fourth front body circumferential region in the left - right direction, the pants - type absorbent article according to any one of aspects 18 to 22.

[0055] According to the pants - type absorbent article of aspect 23, in the third front body circumferential region between the upper end and the lower end of the front body circumferential part, a contraction folding starting point is formed and it easily enters the recess of the wearer's lower abdomen part, so that the front body circumferential part is difficult to slip off and the fit can be improved.

[0056] (Aspect 24) When the front body circumferential part is divided into four equal parts in the vertical direction between the upper end and the lower end of the side joint part, and the first region from the upper side is defined as the first front body circumferential region and the second region from the upper side is defined as the second front body circumferential region, in the natural state, the average length in the left-right direction of the third front body circumferential region and the fourth front body circumferential region is shorter than the average length in the left-right direction of the first front body circumferential region and the second front body circumferential region, the pant-type absorbent article according to any one of Aspects 18 to 23.

[0057] According to the pant-type absorbent article of aspect 24, in the upper half region of the front body circumferential part where the abdominal fluctuations are large, the shrinkage amount in the left-right direction becomes small, so that the front body circumferential part is less likely to interfere with the movement of the wearer's abdomen and is less likely to cause discomfort to the wearer. On the other hand, in the lower half region of the front body circumferential part where the abdominal fluctuations are small, the shrinkage amount in the left-right direction becomes large, so that the front body circumferential part is likely to be fixed to the concave part of the lower abdomen of the wearer and it is difficult for displacement to occur. Thereby, the fit of the front body circumferential part can be improved.

[0058] (Aspect 25) Having a main body joint part that joins the absorbent main body and the front body circumferential part, in the vertical direction, the upper end of the main body joint part is located above the upper end of the third front body circumferential region, the pant-type absorbent article according to any one of Aspects 18 to 24.

[0059] According to the pant-type absorbent article of aspect 25, in the vertical direction, since the entire third front body circumferential region is joined to the absorbent main body via the main body joint part, the absorbent main body is pressed against the skin side of the wearer by the large contraction force of the third front body circumferential region, and it is difficult for the absorbent main body to shift downward. Therefore, the fit of the absorbent main body and the leg gather parts provided at both ends thereof is further improved.

[0060] (Aspect 26) The absorbent main body has a liquid-absorbent absorber, and in the vertical direction, the upper end of the absorber is located below the upper end of the third front torso circumferential region, the pant-type absorbent article according to any one of aspects 18 to 25.

[0061] According to the pant-type absorbent article of aspect 26, in a portion where the third front torso circumferential region and the absorber do not overlap, since the contraction force of the third front torso circumferential region is hardly inhibited by the highly rigid absorber, a large contraction force can be applied to the recess of the wearer's lower abdomen. As a result, the fit of the absorbent main body is further improved, and it becomes easier to suppress the leg gather portion from shrinking inward.

[0062] (Aspect 27) The front torso circumferential portion has a plurality of torso circumferential elastic members that expand and contract in the left-right direction with a space in the vertical direction, and the average pitch in the left-right direction of the leg gather elastic member disposed in the leg gather portion is larger than the average pitch in the vertical direction of the torso circumferential elastic member disposed in the third front torso circumferential region, the pant-type absorbent article according to any one of aspects 18 to 26.

[0063] According to the pant-type absorbent article of aspect 27, since the pitch of the LG elastic member is relatively large, the surface pressure of the leg gather portion is less likely to become excessively large, and it is less likely for the mark of the LG elastic member to be left on the skin of the wearer.

[0064] ===Embodiment=== As the pant-type absorbent article according to the present embodiment, a pant-type disposable diaper 1 for infants (hereinafter, also simply referred to as "diaper 1") will be described as an example. However, the pant-type absorbent article is not limited to disposable diapers for infants, and can also be used as disposable diapers for adults, sanitary shorts, etc.

[0065] <Configuration of the pant-type disposable diaper 1> FIG. 1 is a schematic perspective view of the pant-type disposable diaper 1. FIG. 2 is a plan view of the diaper 1 in a deployed and stretched state. FIG. 3 is a schematic cross-sectional view showing the view taken along the line A-A in FIG. 2.

[0066] In the panty-shaped state shown in FIG. 1, the diaper 1 has vertical, horizontal, and front-rear directions that intersect with each other, and a waist opening BH and a pair of leg openings LH are formed. In the vertical direction, the side of the waist opening BH is the upper side, and the crotch side is the lower side. Also, as shown in the cross-sectional view of FIG. 3, the direction in which the materials constituting the diaper 1 are laminated is referred to as the thickness direction. The side that contacts the wearer's body (skin) in the thickness direction is referred to as the skin side, and the side that does not contact the wearer's body (skin) is referred to as the non-skin side.

[0067] Also, the "extended state" of the diaper 1 means a state in which the entire diaper 1 (the entire product) is extended without wrinkles by extending each elastic member provided in the diaper 1 (for example, the LG elastic member 17, the waist elastic members 23, 33, etc., described later). Specifically, it refers to a state in which each member constituting the diaper 1 (for example, the absorbent body 10, the waist portions 20, 30, etc., described later) is extended until the dimensions of the member alone are equal to or close to the dimensions of the member.

[0068] On the other hand, the state when the diaper 1 is left for a predetermined time is referred to as the "natural state". For example, the diaper 1 in the product state is taken out of the package, and the waist portions 20, 30 are pulled outward in the horizontal direction to the "extended state". After continuing this extended state for 15 seconds, the pulling of the diaper 1 is released and it is placed on a flat surface such as a table. Then, the state after 5 minutes have passed in such a flat placement is the natural state.

[0069] The diaper 1 has an absorbent body 10, a front waist portion 20, and a rear waist portion 30, which are three members rectangular in plan view. When the diaper 1 is worn, the front waist portion 20 (the abdominal waist portion) is applied to the abdominal side of the wearer, and the rear waist portion 30 (the dorsal waist portion) is applied to the dorsal side of the wearer.

[0070] In the diaper 1 in the unfolded state shown in FIG. 2, the front body circumferential portion 20 and the rear body circumferential portion 30 are arranged such that their longitudinal directions are along the left - right direction of the diaper 1. And, at the central portion of the front body circumferential portion 20 in the left - right direction, the end portion on one longitudinal side (front side) of the absorbent body 10 is joined, and at the central portion of the rear body circumferential portion 30 in the left - right direction, the end portion on the other longitudinal side (rear side) of the absorbent body 10 is joined.

[0071] Also, in the diaper 1 in the unfolded state shown in FIG. 2, the absorbent body 10 is folded in half at a predetermined position FL in the longitudinal direction (which is also a predetermined position in the front - rear direction) such that the longitudinal direction of the absorbent body 10 is along the up - down direction of the diaper 1. The front body circumferential portion 20 and the rear body circumferential portion 30 are joined at both end portions in the left - right direction using joining means such as heat welding or ultrasonic welding, and a pair of side joining portions 2, 2 are formed. Thereby, the diaper 1 becomes a pants - type state (see FIG. 1) having a body circumferential opening BH and a pair of leg circumferential openings LH. Note that the predetermined position FL is the lower end in the up - down direction and the central position in the front - rear direction in the pants - type diaper 1.

[0072] (Absorbent body 10) FIG. 4 is a plan view and a cross - sectional view of the absorbent body 10 in the stretched state. As shown in the cross - sectional views of FIGS. 3 and 4, the absorbent body 10 includes an absorber 11, a topsheet 12 disposed closer to the skin side than the absorber 11, a leak - proof film 13 disposed closer to the non - skin side than the absorber 11, and an outer cover sheet 14 disposed closer to the non - skin side than the leak - proof film 13 and forming the outer package of the absorbent body 10. Also, on both sides of the absorbent body 10 in the left - right direction, a pair of leak - proof wall portions LSG and a pair of leg gather portions LG are respectively provided.

[0073] The absorber 11 has an absorbent core 11a that absorbs and holds excreted liquids such as urine, and a liquid-permeable core wrap sheet 11b that covers the absorbent core 11a. Examples of the absorbent core 11a include those formed by shaping liquid-absorbent fibers such as pulp containing a superabsorbent polymer (SAP) into a predetermined shape. Alternatively, a so-called SAP sheet formed by fixing SAP particles to each other without including liquid-absorbent fibers and shaping them into a flat plate may be used. On the other hand, examples of the core wrap sheet 11b include non-woven fabrics such as tissue paper and SMS non-woven fabric.

[0074] The absorbent core 11a of the present embodiment has a constricted portion 11c between the front end portion and the rear end portion in the longitudinal direction, where the length in the left-right direction (width) is shorter compared to the front end portion and the rear end portion, and has a substantially hourglass shape in plan view as shown in FIG. 4. This constricted portion 11c is the portion sandwiched between the wearer's legs when the diaper 1 is worn. Since the length in the left-right direction (width) of the absorbent core 11a is shorter (narrower) in the constricted portion 11c, the absorber 11 is more likely to fit the wearer's crotch. However, the shape of the absorbent core 11a is not limited to this, and for example, the absorbent core 11a (absorber 11) may be rectangular.

[0075] The top sheet 12 is a liquid-permeable sheet member that covers the absorber 11 from the skin side, and for example, a hydrophilic air-through non-woven fabric or a spunbond non-woven fabric is used. In the present embodiment, as shown in the cross-sectional view of FIG. 4, both side portions in the left-right direction are folded back to the non-skin side so as to enclose the absorber 11. Also, a second sheet (not shown) equivalent to the top sheet 12 may be provided between the top sheet 12 and the absorber 11.

[0076] The leak-proof film 13 is a breathable and liquid-impermeable sheet member provided on the non-skin side of the absorber 11. For example, a microporous breathable resin film in which a plurality of fine pores are provided in a sheet mainly made of a resin such as polyethylene or polypropylene can be used.

[0077] The outer cover sheet 14 is provided on the outermost non-skin side of the absorbent body 10 and is a sheet member that constitutes the outer cover of the absorbent body 10. For example, an air-through non-woven fabric, a spunbond non-woven fabric, or the like can be used.

[0078] The outer cover sheet 14 extends outward in the left-right direction beyond the outer ends 11es, 11es of the absorber 11. The extended portion is folded inward in the left-right direction and toward the skin side in the thickness direction with the outer ends 10es, 10es of the absorbent body 10 in the left-right direction as the folding positions, forming a folded portion 14f. Then, in a state where the non-folded portion and the folded portion 14f of the outer cover sheet 14 are overlapped in the thickness direction, they are joined to each other via a leg gather joining portion 50 (hereinafter, also referred to as "LG joining portion 50"), thereby forming a pair of leg gather portions LG, LG. In FIG. 4, the non-folded portion and the folded portion 14f of the outer cover sheet 14 are joined by the first LG joining portion 51 to the fourth LG joining portion 54 with a leak-proof film 13 sandwiched therebetween in the thickness direction.

[0079] Also, between the outer cover sheet 14 forming the leg gather portion LG and the folded portion 14f in the thickness direction, a plurality of leg gather elastic members 17, 17... (hereinafter, also referred to as "LG elastic members 17") such as thread rubber are provided at predetermined intervals in the left-right direction in a state of being stretched at a predetermined elongation ratio in the longitudinal direction. Thereby, elasticity along the longitudinal direction (up-down direction) is imparted to the leg gather portion LG. Since the plurality of LG elastic members 17, 17 are arranged side by side in the left-right direction, the leg gather portion LG has a planar shape that protrudes outward from both sides of the absorbent body 10 in the left-right direction as shown in FIG. 1.

[0080] In this embodiment, three LG elastic members 17 are provided on each of the leg gather portions LG on both sides in the left - right direction. Hereinafter, the LG elastic member 17 arranged on the innermost side in the left - right direction is the inner LG elastic member 17a, the LG elastic member 17 arranged on the outermost side in the left - right direction is the outer LG elastic member 17c, and the LG elastic member 17 provided between the inner LG elastic member 17a and the outer LG elastic member 17c in the left - right direction is the intermediate LG elastic member 17b. In FIG. 4, only one intermediate LG elastic member 17b is provided between the inner LG elastic member 17a and the outer LG elastic member 17c, but a plurality of intermediate LG elastic members 17b may be provided. That is, depending on the length (width) of the leg gather portion LG in the left - right direction, four or more LG elastic members 17 may be provided. Each of the LG elastic members 17a - 17c exhibits elasticity at least in the portion indicated by the solid line (the range in the longitudinal direction of the absorbent body 10) in the plan view of FIG. 4.

[0081] Also, as shown in FIG. 4, in the left - right direction, below the LG elastic member 17 (inner LG elastic member 17a) and outside the left - right outer ends 11es of the absorber 11, an under - crotch elastic member 18 such as thread rubber is provided in a state of being stretched in the longitudinal direction. The under - crotch elastic member 18 exhibits elasticity at least in the portion indicated by the solid line in the plan view of FIG. 4. For the wearing comfort of the diaper 1, the leg gather portion LG and the absorber 11 are pushed upward to the wearer's skin side by the elasticity exhibited by the under - crotch elastic member 18. Thereby, the leg gather portion LG and the absorber 11 can be more easily fitted to the wearer's crotch and under - thigh, and lateral leakage of excrement (such as urine) can be effectively suppressed.

[0082] Also, as shown in FIG. 2, a part of the lower thigh elastic member 18 has a portion that overlaps with the ventral body circumferential elastic member 23 and the dorsal body circumferential elastic member 33 when viewed in the thickness direction. Thereby, the stretching force along the longitudinal direction by the lower thigh elastic member 18 and the stretching force along the left - right direction by the body circumferential elastic members 23 and 33 are more likely to be interlocked, and the fit can be further improved. However, the lower thigh elastic member 18 may intersect with only one of the body circumferential elastic members 23 and 33 (either the ventral or the dorsal side), or may not intersect with either of the body circumferential elastic members 23 and 33.

[0083] Also, a part of the folded - back portion 14f of the outer cover sheet 14 forms a standing portion 14s that stands up on the skin side at a predetermined position outside the absorber 11 in the left - right direction. In FIG. 4, taking the inner end 51ei in the left - right direction of the first LG joint portion 51, which is provided on the skin side in the thickness direction and is the innermost in the left - right direction among the plurality of LG joint portions 50, as the standing starting point, the standing portion 14s stands up toward the skin side in the thickness direction.

[0084] Then, as shown in FIG. 4, the standing portion 14s is folded back from the inner side to the outer side in the left - right direction at the position of the tip 14st, and between the overlapping standing portions 14s and 14s in the thickness direction, a plurality of leak - proof wall elastic members 19 such as thread rubber are provided in a state of being stretched in the longitudinal direction. When the diaper 1 is worn, due to the elasticity exhibited by the leak - proof wall elastic member 19, the tip 14st of the standing portion 14s stands up from the standing starting point 51ei toward the skin side, thereby forming a pair of leak - proof wall portions LSG, LSG.

[0085] (Front body circumferential portion 20) The front body circumferential portion 20 has a body circumferential sheet 21 and a plurality of body circumferential elastic members 23, 23,.... The body circumferential sheet 21 is a sheet member having a rectangular shape in plan view, and is folded back at the upper end 20et in the vertical direction of the front body circumferential portion 20 as shown in FIG. 3, and is joined in a state of being laminated in the thickness direction. As the body circumferential sheet 21, for example, an SMS nonwoven fabric (spunbond - meltblown - spunbond nonwoven fabric), a spunbond nonwoven fabric, an air - through nonwoven fabric, etc. can be applied. Further, between the skin side and the non - skin side in the thickness direction of the body circumferential sheet 21 folded back at the upper end 20et, a plurality of body circumferential elastic members 23, 23,... such as thread rubber are provided at intervals in the vertical direction in a state of being stretched at a predetermined elongation ratio in the left - right direction. Due to the elasticity exhibited by the plurality of body circumferential elastic members 23, the front body circumferential portion 20 is imparted with elasticity along the left - right direction. Also, a part of the plurality of body circumferential elastic members 23, 23,... has a portion cut in the central part in the left - right direction.

[0086] Also, the front body circumferential portion 20 may have a skin - facing sheet 25. The skin - facing sheet 25 is a sheet member arranged to cover the upper end portion of the absorbent body 10 from the skin side as shown in FIG. 3, and has a function as a cover sheet. Thereby, when the diaper 1 is worn, it is suppressed that the upper - end edge of the absorbent body 10 digs into the wearer's skin. The skin - facing sheet 25 is formed of a sheet member such as a nonwoven fabric equivalent to the body circumferential sheet 21. However, the skin - facing sheet 25 does not necessarily have to be provided.

[0087] (Rear body circumferential portion 30) The rear body circumferential portion 30 has substantially the same configuration as the front body circumferential portion 20. That is, the rear body circumferential portion 30 has a body circumferential sheet 31 and a plurality of body circumferential elastic members 33, 33, …. The body circumferential sheet 31 is folded back at the upper end 30et in the vertical direction of the rear body circumferential portion 30 in substantially the same manner as the body circumferential sheet 21, and is joined in a laminated state in the thickness direction. Further, between the skin side and the non-skin side in the thickness direction of the folded body circumferential sheet 31, a plurality of body circumferential elastic members 33, 33, … such as thread rubber are provided at intervals in the vertical direction in a state of being stretched at a predetermined elongation ratio in the left-right direction. Further, the rear body circumferential portion 30 may have a skin surface sheet 35 substantially the same as the skin surface sheet 25.

[0088] <Regarding the fit of the leg gather portion LG> Subsequently, the fit of the leg gather portion LG when the diaper 1 is worn will be described. First, as a comparative example, the problems of the leg gather portion that have occurred in conventional pants-type absorbent articles will be described. FIGS. 5A and 5B are diagrams for explaining the fit of the leg gather portion LG at the crotch (ankle portion) of the wearer when wearing a conventional pants-type diaper.

[0089] Conventionally, in pants-type absorbent articles, in order to improve the fit at the ankle portion and suppress lateral leakage of excrement, the length in the left-right direction of the leg gather portion LG may be increased (the width may be widened). In that case, it is important to closely fit the wide leg gather portion to the skin (ankle) of the wearer on the surface. That is, at the time of wearing, it is required to fit it tightly so that no gap is generated between the leg gather portion LG and the skin of the wearer.

[0090] In contrast, in the diaper of FIG. 5A, by narrowing the pitch (the interval in the left-right direction) of the elastic members (LG elastic members) provided in the leg gather portion LG and arranging a large number of LG elastic members, the stretching and contracting force of the entire leg gather portion LG is increased. As a result, when wearing the diaper, it is possible to make it difficult for a gap to occur between the leg gather portion LG and the skin of the wearer. However, in the configuration as shown in FIG. 5A, due to the elasticity exhibited by a large number of LG elastic members, the surface pressure of the leg gather portion LG tends to become excessively high, and there is a risk of causing discomfort such as the leg gather portion LG digging into the wearer's leg movement. In particular, when a wearer is an infant with sensitive skin, etc., there is a risk that the leg gather portion LG strongly presses against the skin, making it easier for redness or swelling to occur in the leg movement.

[0091] On the other hand, in the diaper of FIG. 5B, by widening the interval in the left-right direction of the elastic members (LG elastic members) provided in the leg gather portion LG and reducing the number of arranged LG elastic members, the surface pressure of the leg gather portion LG is prevented from becoming excessively high. In this case, by reducing the surface pressure, it becomes possible to suppress the digging into the wearer's leg movement. However, since the number of LG elastic members themselves is small, the rigidity of the leg gather portion LG decreases. As a result, there is a risk that the leg gather portion LG easily wrinkles from the outside (tip side) to the inside (base side) in response to the contraction of the LG elastic members. For example, when the wearer moves the leg, if the position of the LG elastic member moves from the outside to the inside, as shown in FIG. 5B, the LG elastic member acts like a joint and the leg gather portion LG is likely to deform like a bellows and wrinkle, deteriorating the fit.

[0092] Therefore, in the diaper 1 of the present embodiment, while preventing the surface pressure of the leg gather portion LG from becoming excessively high, the rigidity of the leg gather portion LG is increased so that the leg gather portion LG is less likely to wrinkle inward during wearing. FIG. 6 is a schematic cross-sectional view for explaining the structure of the leg gather portion LG of the diaper 1. FIG. 6 corresponds to a view obtained by enlarging a part of the cross-sectional view of FIG. 4.

[0093] As shown in FIG. 6, the leg gather portion LG of the diaper 1 is formed between the outer end 10es of the absorbent body 10 and the inner end 51ei of the first LG joint portion 51 which is the starting point of the standing of the leak - proof wall portion LSG in the left - right direction. And a plurality of leg gather elastic members (LG elastic members) 17 are provided in the leg gather portion LG. When an elastic member is arranged at a position overlapping with the starting point (inner end 51ei) of the standing of the leak - proof wall portion LSG in the left - right direction, the said elastic member shall be treated as the crotch elastic member 18 instead of the LG elastic member 17.

[0094] In the present embodiment, three LG elastic members 17, namely, the inner LG elastic member 17a, the middle LG elastic member 17b, and the outer LG elastic member 17c, are provided from the inner side to the outer side in the left - right direction. And each of the LG elastic members 17a to 17c is arranged so that the intervals between two adjacent LG elastic members 17, 17 in the left - right direction are all 5 mm or more. By providing the LG elastic members 17 at an interval as wide as 5 mm or more, the expansion and contraction force acting on the unit area of the leg gather portion LG becomes smaller compared with the case where the interval is less than 5 mm, and the surface pressure of the leg gather portion LG can be reduced.

[0095] Furthermore, in the diaper 1, among the plurality of LG elastic members 17 provided in the leg gather portion LG, each LG elastic member 17 is arranged so that the contraction force of the LG elastic member 17 arranged on the outer side in the left - right direction becomes as small as possible. That is, when a certain LG elastic member 17 among the plurality of LG elastic members 17 is regarded as the first leg gather elastic member and the LG elastic member 17 arranged on the outer side in the left - right direction than the first leg gather elastic member is regarded as the second leg gather elastic member, the LG elastic members 17 are arranged so that the contraction force of the first leg gather elastic member is larger than the contraction force of the second leg gather elastic member.

[0096] For example, when the inner LG elastic member 17a is used as the first leg gather elastic member in FIG. 6, at least one of the intermediate LG elastic member 17b and the outer LG elastic member 17c serves as the second leg gather elastic member. Then, the LG elastic members 17a to 17c are arranged such that the contraction force of the inner LG elastic member 17a is greater than that of at least one of the intermediate LG elastic member 17b and the outer LG elastic member 17c. Since the contraction force of the LG elastic member 17 arranged on the inner side (the root side of the leg gather portion LG) in the left-right direction is strong and the contraction force of the LG elastic member 17 arranged on the outer side (the tip side of the leg gather portion LG) is weak, when the diaper 1 is worn, the leg gather portion LG easily follows the movement of the wearer's legs and fits well. Therefore, it is possible to prevent the outer (tip side) LG elastic member 17 from moving to the inner side (root side), and it is possible to prevent the leg gather portion LG from shrinking inward as shown in FIG. 5B.

[0097] In addition, the leg gather portion LG of the diaper 1 is provided with a rigidity imparting means for imparting rigidity to the leg gather portion LG. Specifically, the leg gather joint portion 50 (51 to 54) that joins the sheet members constituting the leg gather portion LG in the thickness direction functions as a rigidity imparting means, thereby increasing the rigidity of the leg gather portion LG. In the present embodiment, the leg gather joint portion 50 (hereinafter also referred to as the "LG joint portion 50") is formed by an adhesive such as a hot melt adhesive, for example.

[0098] Note that the LG elastic member 17 itself is not included in the rigidity imparting means. At least a portion of the LG joint portion 50 that does not overlap with the LG elastic member 17 when viewed in the thickness direction functions as a rigidity imparting means. In the case of FIG. 6, at least a part of the first LG joint portion 51 to the third LG joint portion 53 and the fourth LG joint portion 54 functions as a rigidity imparting means.

[0099] And in the diaper 1, the rigidity imparting means (LG joints 51 to 54) is continuously provided along the longitudinal direction of the absorbent body 10 in a region below the lower end 2eb of the side joint 2 that joins the front body circumferential portion 20 and the rear body circumferential portion 30 (see FIG. 4). As a result, the rigidity is increased over a wide range of the leg gather portion LG, making it easier for the leg gather portion LG to maintain its surface shape, and making it more difficult for the leg gather portion LG to shrink inward. Therefore, a diaper 1 is realized that has a leg gather portion LG with a not-too-high surface pressure and is difficult to shrink inward. That is, even if the arrangement interval of the LG elastic members 17 is widened to reduce the surface pressure, the leg gather portion LG can easily fit against the wearer's leg in a planar manner, and it is possible to make it difficult for the user to be reminded of concerns such as lateral leakage of excrement.

[0100] Here, the contraction force of the LG elastic member 17 can be measured as follows. FIGS. 7A to 7C are diagrams for explaining the method of measuring the contraction force of the LG elastic member 17. First, a test piece TP is created by cutting out a portion to be measured including the LG elastic member 17 from the diaper 1. Specifically, as shown in FIG. 7A, the absorbent body 10 of the diaper 1 in the unfolded and extended state is cut in the vertical direction (the longitudinal direction of the absorbent body 10) at the lower end 20eb of the front body circumferential portion 20 (corresponding to the lower end 2eb of the side joint 2 in the diaper 1) and at the lower end 30eb of the rear body circumferential portion 30 (the lower end 2eb of the side joint 2). Next, the cut absorbent body 10 is cut in the left-right direction at the starting point of the standing-up of the leak-proof wall portion LSG (the inner end 51ei of the first LG joint 51), and separated into the leg gather portion LG and the leak-proof wall portion LSG.

[0101] Next, for each of the plurality of LG elastic members 17 provided in the leg gather portion LG, cut the LG elastic member 17 at positions 2.5 mm on both sides in the left-right direction to obtain a test piece TP with a width of 5 mm centered on the LG elastic member 17. In FIG. 7B, a case is shown where a strip-shaped portion indicated by diagonal lines with a width of 5 mm centered on the intermediate LG elastic member 17b is cut out as the test piece TP. Similarly, for the inner LG elastic member 17a and the outer LG elastic member 17c, strip-shaped portions with a width of 5 mm are also cut out as the test piece TP. In the case where a region with a width of 2.5 mm can be secured only on one side in the left-right direction of the LG elastic member 17 (for example, when the outer LG elastic member 17c is provided at the tip position of the leg gather portion LG, etc.), the test piece TP having a width of 2.5 mm only on one side is used.

[0102] Next, as shown in FIG. 7C, for the test piece TP in the natural state, clamp both end portions in the longitudinal direction with the chucks of a known tensile testing machine (for example, a universal material testing machine manufactured by Instron Corporation), and adjust the distance Lc between both chucks to be 100 mm. From this state, expand the distance Lc at a predetermined speed (100 mm / min) until the test piece TP is extended to 0.9 times the length when it is most extended. That is, extend the test piece TP until the length in the longitudinal direction of the test piece TP becomes 0.9 times the length in the extended state. Next, contract the test piece TP until it reaches 0.7 times the length when it is most extended. That is, contract the test piece TP until the length in the longitudinal direction of the test piece TP becomes 0.7 times the length in the extended state. Repeat this cycle 2 times, and at the time of contraction in the second cycle, measure the magnitude of the force (N) when the length in the longitudinal direction of the test piece TP (the distance Lc between the chucks) is contracted until it becomes 0.7 times the length in the extended state. Repeat such measurement a predetermined number of times (for example, 3 times), and take the average of the measured values as the contraction force of the LG elastic member 17 that is the object to be measured.

[0103] In addition, in the leg gather portion LG of the diaper 1, among the two LG elastic members 17, 17 arranged adjacent to each other in the left - right direction, the contraction force of the LG elastic member 17 arranged on the outer side in the left - right direction is preferably equal to or less than the contraction force of the LG elastic member 17 arranged adjacent to it on the inner side. That is, when comparing the contraction forces of the two LG elastic members 17, 17 arranged adjacent to each other in the left - right direction, the contraction force of the LG elastic member 17 arranged on the outer side is preferably equal to or less than the contraction force of the LG elastic member 17 arranged on the inner side.

[0104] With such a configuration, since the contraction force of the LG elastic member 17 gradually decreases from the inner side to the outer side in the left - right direction, the leg gather portion LG can more easily follow the movement of the wearer's leg, and the bunching of the leg gather portion LG is also more likely to be suppressed. Therefore, while suppressing the surface pressure of the leg gather portion LG from becoming excessively high, the fitting property can be further enhanced along the leg - bending shape of the wearer.

[0105] In addition, among the two LG elastic members 17, 17 arranged adjacent to each other in the left - right direction in the leg gather portion LG, the value obtained by dividing the length of the LG elastic member 17 arranged on the outer side in the left - right direction in its natural state by the length when it is stretched most along the longitudinal direction (that is, the length of the LG elastic member 17 in the stretched state) is preferably equal to or less than the value obtained by dividing the length of the LG elastic member 17 arranged adjacent to it on the inner side in its natural state by the length in the stretched state. That is, when comparing the contraction ratios of the two LG elastic members 17, 17 arranged adjacent to each other in the left - right direction, the contraction ratio of the LG elastic member 17 arranged on the outer side is preferably equal to or less than the contraction ratio of the LG elastic member 17 arranged on the inner side.

[0106] With such a configuration, the rate of contraction (contraction rate) of the LG elastic member 17 from the inside to the outside in the left-right direction gradually decreases. That is, the contraction force of the LG elastic member 17 gradually decreases. As a result, the leg gather portion LG is more likely to follow the movement of the wearer's leg, and the bunching of the leg gather portion LG is also likely to be suppressed. Therefore, it is possible to enhance the fitness along the leg bending shape of the wearer while suppressing the surface pressure of the leg gather portion LG from becoming excessively high.

[0107] Further, among the two LG elastic members 17, 17 arranged adjacent to each other in the left-right direction in the leg gather portion LG, the cross-sectional area of the LG elastic member arranged on the outer side in the left-right direction in the natural state is preferably equal to or larger than the cross-sectional area of the LG elastic member 17 arranged adjacent to the inner side in the natural state.

[0108] In a normal case, the larger the cross-sectional area of the LG elastic member 17, the larger the diameter of the LG elastic member 17, so the area for applying the contraction force to the leg gather portion LG becomes wider. That is, an increase in the force (pressure) acting per unit area of the leg gather portion LG can be suppressed. Therefore, even if the contraction force of the LG elastic member 17 is increased on the inner side in the left-right direction of the leg gather portion LG, the surface pressure is suppressed from becoming excessively high, and it is difficult for linear marks due to the LG elastic member 17 to be formed on the skin of the wearer.

[0109] Also, as shown in FIG. 6, in the left-right direction, the region from the outermost end 10es of the leg gather portion LG to the innermost inner LG elastic member 17a is defined as the leg gather elastic region ER. At this time, the length Wer in the left-right direction of the leg gather elastic region ER in the extended state is at least half of the length Wlg in the left-right direction of the leg gather portion LG in the extended state. That is, in at least half of the leg gather portion LG, the expansion and contraction force by the LG elastic member 17 acts.

[0110] And when the number of LG elastic members 17 arranged in the leg gather elastic region ER (three in the diaper 1) equally divides the leg gather elastic region ER in the left - right direction (into three equal parts in the diaper 1), each of the divided regions has an LG elastic member 17 arranged therein. In FIG. 6, the inner LG elastic member 17a is arranged in the inner region ERa in the left - right direction when the leg gather elastic region ER is divided into three equal parts, the middle LG elastic member 17b is arranged in the central region ERb, and the outer LG elastic member 17c is arranged in the outer region ERc in the left - right direction.

[0111] That is, in more than half of the region of the leg gather part LG, the LG elastic members 17 are evenly arranged. If there is a bias in the pitch of the LG elastic members 17 in the left - right direction, the pressure will be high in the part of the leg gather part LG where there are many elastic members locally, and the region with few elastic members is likely to wrinkle. In contrast, in the diaper 1, since the LG elastic members 17 are evenly arranged in the leg gather part LG, it is difficult for a local rigidity difference to occur, and it is easier to maintain the surface shape. Also, since it is difficult for local pressure to act on the wearer's leg crotch part, it is easy to suppress the skin from getting chafed or turning red.

[0112] Furthermore, in the leg gather part LG of the diaper 1, a rigidity - imparting means is provided in each region where the leg gather elastic region ER is equally divided (into three equal parts). In FIG. 6, in the inner region ERa in the left - right direction among the three - divided leg gather elastic regions ER, the second LG joint part 52 and the fourth LG joint part 54 are provided. Similarly, in the central region ERb in the left - right direction, a part of the third LG joint part 53 and the fourth LG joint part 54 are provided, and in the outer region ERc in the left - right direction, a part of the third LG joint part 53 is provided. As a result, since the rigidity of each region (ERa - ERc) where the contraction force of the LG elastic member 17 acts is increased, the wrinkling of the leg gather part LG is suppressed, and it becomes easier to maintain the surface shape.

[0113] In addition, in the leg gather portion LG, when viewed in the thickness direction, a rigidity imparting means is provided between two LG elastic members 17, 17 arranged adjacent to each other in the left - right direction. In FIG. 6, when viewed in the thickness direction, a second LG joint portion 52 and a fourth LG joint portion 54 are provided between the inner LG elastic member 17a and the intermediate LG elastic member 17b adjacent to each other in the left - right direction. Similarly, a third LG joint portion 53 and a fourth LG joint portion 54 are provided between the intermediate LG elastic member 17b and the outer LG elastic member 17c.

[0114] By increasing the rigidity of the region between the LG elastic members 17, 17 by the rigidity imparting means, it becomes difficult to form a bending starting point between the LG elastic members 17, 17, so that the gathering of the leg gather portion LG is more easily suppressed. Note that the LG joint portion 50 (rigidity imparting means) may be arranged other than the configuration shown in FIG. 6. For example, an inner LG elastic member 17a and an intermediate LG elastic member 17b may be provided on the skin side in the thickness direction from the leak - proof film 13, and a rigidity imparting means corresponding to the second LG joint portion 52 may be provided on the non - skin side in the thickness direction from the leak - proof film 13.

[0115] In addition, in the diaper 1 of the present embodiment, the contraction force per unit width of the leg gather portion LG is equal to or less than the contraction force per unit width of the leak - proof wall portion LSG. That is, the value obtained by dividing the contraction force when returning from the length extended to 0.9 times the length when the leg gather portion LG is extended most along the longitudinal direction (extended state) to 0.7 times the length by the width of the leg gather portion LG (the length Wlg in the left - right direction in FIG. 6) is equal to or less than the value obtained by dividing the contraction force when returning from the length extended to 0.9 times the length when the leak - proof wall portion LSG is extended most along the longitudinal direction (extended state) to 0.7 times the length by the width of the leak - proof wall portion LSG (the length Wlsg in the thickness direction in FIG. 6).

[0116] With such a configuration, compared to the reverse case (the contraction force per unit width of the leg gather portion LG > the contraction force per unit width of the leak prevention wall portion LSG), the surface pressure of the leg gather portion LG becomes relatively small. Therefore, when the diaper 1 is worn, it is possible to make it difficult for the wearer's legs to become swollen or reddened when moving. The contraction force per unit width of the leg gather portion LG and the leak prevention wall portion LSG can be measured according to the method described with reference to FIG. 7. That is, as test pieces TP, the portion of the leg gather portion LG shown in FIG. 7A and the portion of the leak prevention wall portion LSG are cut out respectively. Then, a tensile test is performed on each test piece TP as shown in FIG. 7C to measure the contraction force, and by dividing by the length (width) in the left-right direction of the test piece TP, the contraction force per unit width of the leg gather portion LG and the leak prevention wall portion LSG can be obtained.

[0117] Also, as described above, the rigidity imparting means for imparting rigidity to the leg gather portion LG of the diaper 1 is realized by an adhesive that adheres the sheet members constituting the leg gather portion LG in the thickness direction. Specifically, rigidity is imparted to the leg gather portion LG by the first LG joint portions 51 to 53 (adhesives) that join the folded-back portion 14f of the outer sheet 14 and the leak prevention film 13 in the thickness direction (see FIG. 6). Similarly, rigidity is imparted to the leg gather portion LG by the fourth LG joint portion 54 (adhesive) that joins the outer sheet 14 (the non-folded portion) and the leak prevention film 13 in the thickness direction (see FIG. 6).

[0118] By joining sheet members laminated in the thickness direction to each other with an adhesive, the rigidity of the leg gather portion LG is enhanced even in a portion where the LG elastic member 17 is not provided (a portion not overlapping with the LG elastic member 17). And, since a plurality of sheet members constituting the leg gather portion LG are joined in a state of being laminated in the thickness direction, each sheet member is likely to be maintained in a planar shape, and it is difficult for the entire leg gather portion LG to wrinkle. Also, since an adhesive such as a hot melt adhesive is solidified at normal temperature, the adhesive itself has rigidity, and it becomes easier to ensure the rigidity of the leg gather portion LG. Note that the rigidity imparting means is not limited to an adhesive, and may be realized by means such as welding described later or providing other sheet members (see FIG. 8).

[0119] Further, in the diaper 1, the rigidity imparting means is provided in an area that is at least half of the area of the leg gather elastic region ER. In FIG. 6, the fourth LG joint portion 54 is provided in an area that occupies most of the areas of the inner region ERa and the central region ERb when the leg gather elastic region ER is divided into three equal parts in the left-right direction. Further, the second LG joint portion 52 and the third LG joint portion 53 are also provided. That is, the rigidity imparting means is provided in an area that occupies about 2 / 3 of the entire area of the leg gather elastic region ER. Since more than half of the portion of the leg gather elastic region ER where the contraction force by the LG elastic member 17 acts is enhanced in rigidity by the rigidity imparting means, the leg gather elastic region ER is likely to be maintained in a planar shape, and it is easy to suppress the occurrence of wrinkles and the like.

[0120] In addition, a leak-proof film 13, which is a liquid-impermeable sheet member, is provided in the leg gather portion LG. In the left-right direction, the outer end 13es of the leak-proof film 13 is located between the outermost outer LG elastic member 17c and the second outermost intermediate LG elastic member 17b (see Fig. 6). Since the leak-proof film 13 is provided up to the vicinity of the tip (outer end 10es in the left-right direction) of the leg gather portion LG, the rigidity is increased in a wide range of the leg gather portion LG as compared with the case where the leak-proof film 13 is not provided, and it becomes easier to maintain the surface shape. On the other hand, since the leak-proof film 13 is not provided outside the outer LG elastic member 17c in the left-right direction, it is suppressed that the tip edge (outer end 10es) of the leg gather portion LG becomes hard, and even when the tip edge contacts the skin of the wearer when the diaper 1 is worn, it is difficult to cause a sense of discomfort or uneasiness to the wearer.

[0121] Furthermore, in the leg gather portion LG of the diaper 1, in the left-right direction, no rigidity-imparting means is provided outside the outermost outer LG elastic member 17c (see Fig. 6). Therefore, the rigidity of the tip edge (outer end 10es) of the leg gather portion LG is not increased, and flexibility is maintained. Thereby, even when the tip edge contacts the skin of the wearer when the diaper 1 is worn, it is more difficult to cause a sense of discomfort or uneasiness to the wearer.

[0122] In addition, the width of the leg gather portion LG in the left - right direction in the extended state is equal to or greater than the standing height of the leakage - preventing wall portion LSG in the extended state (the maximum height when the leakage - preventing wall portion LSG stands up from the standing start point). In FIG. 6, the distance Wlg in the left - right direction between the outer end 10es of the leg gather portion LG and the standing start point 51ei of the leakage - preventing wall portion LSG is longer than (or may be the same length as) the distance Wlsg from the standing start point 51ei of the leakage - preventing wall portion LSG to the tip 14st of the leakage - preventing wall portion LSG (the standing height of the leakage - preventing wall portion LSG). With such a configuration, when the diaper 1 is worn, even if the leakage - preventing wall portion LSG falls outward in the left - right direction from the standing state, it is suppressed that the fallen leakage - preventing wall portion LSG protrudes outside the tip (outer end 10es) of the leg gather portion LG. Therefore, it is suppressed that a gap is formed by the leakage - preventing wall portion LSG being sandwiched between the leg gather portion LG and the wearer's skin, and it becomes easier to fit the leg gather portion LG to the wearer's leg in a planar manner with respect to the leg movement of the wearer.

[0123] In addition, an inseam elastic member 18 that expands and contracts along the longitudinal direction is provided in the leg gather portion LG of the diaper 1. As shown in FIG. 6, this inseam elastic member 18 is arranged in the left - right direction between the outer end 11es of the absorber 11 and the standing start point 51ei of the leakage - preventing wall portion LSG (that is, the inner end of the leg gather portion LG). Therefore, when the diaper 1 is worn, both outer sides of the absorber 11 in the left - right direction are pushed upward toward the skin side by the elasticity exhibited by the inseam elastic member 18, and it becomes easier for the absorber 11 to fit to the crotch portion of the wearer. In particular, even when the absorber 11 has absorbed excrement and its weight has increased, it is difficult for the absorber 11 to sag downward, so the fit of the entire absorbent body 10 is improved, and it becomes easier to effectively suppress leakage and the like. Also, since the root side of the leg gather portion LG is pushed upward toward the skin side by the elasticity of the inseam elastic member 18, it is possible to more easily fit the leg gather portion LG to the wearer's skin.

[0124] <Modification Example> FIG. 8 is a plan view and a cross-sectional view showing a modified example of the absorbent body 10. FIG. 8 shows the absorbent body 10 in an extended state as in FIG. 4. The absorbent body 10 of the modified example is different from the absorbent body 10 described in FIG. 4 in the configuration of the leg gather portion LG and a part of the top sheet 12.

[0125] The absorbent body 10 of the modified example has a welding portion 60 that joins the outer packaging sheet 14 constituting the leg gather portion LG and the folded portion 14f where the outer packaging sheet 14 is folded back at the outer end 10es in the thickness direction. The welding portion 60 is formed by regularly arranging a number of first welding patterns 61 and second welding patterns 62 along the longitudinal direction, and each of the welding patterns 61 and 62 is formed using known thermal welding or ultrasonic welding. In FIG. 8, the first welding pattern 61 and the second welding pattern 62 are arranged so as to have overlapping portions with each other in the longitudinal direction (vertical direction), and the entire welding portion 60 is formed to be continuous in the longitudinal direction. In FIG. 8, the first welding pattern 61 and the second welding pattern 62 are also arranged so as to have overlapping portions with each other in the short direction (left - right direction).

[0126] Also, in FIG. 8, a leakage - preventing wall portion LSG stands up with the inner end 60ei in the left - right direction of the welding portion 60 as the standing - up starting point. That is, in the left - right direction, the welding portion 60 is provided on the root side of the leg gather portion LG (the standing - up starting point side of the leakage - preventing wall portion LSG), but the welding portion 60 may be provided on the tip side of the leg gather portion LG (the side closer to the outer end 10es than the standing - up starting point 60ei in the left - right direction).

[0127] Such a welding portion 60 further increases the bonding strength between the sheet members laminated in the thickness direction of the leg gather portion LG, and the leg gather portion LG becomes more stable. Also, the welding portion 60 functions as a rigidity - imparting means for imparting rigidity to the leg gather portion LG. In FIG. 8, two types of joint portions, the welding portion 60 and the LG joint portion 50, are provided in the leg gather portion LG, but a configuration may be adopted in which the welding portion 60 is formed instead of the LG joint portion 50.

[0128] In the leg gather portion LG, the sheet members laminated in the thickness direction are joined by the welding portion 60 (LG joint portion 50), so that the rigidity of the leg gather portion LG is enhanced even in a portion where the LG elastic member 17 is not provided (not overlapping). Then, the sheet member constituting the leg gather portion LG is likely to be maintained in a planar shape, and the leg gather portion LG is less likely to wrinkle. Further, since the welding portion 60 and the LG joint portion 50 (such as an adhesive) itself has rigidity, it becomes easier to ensure the rigidity of the leg gather portion LG.

[0129] Also, in the cross-sectional view of the absorbent body 10 shown in FIG. 4, the left and right end portions of the topsheet 12 were folded toward the non-skin side of the absorber 11. On the other hand, in the absorbent body 10 of the modified example, as shown in FIG. 8, the outer ends 12es in the left and right directions of the topsheet 12 extend outward beyond the standing start point 60ei of the leak-proof wall portion LSG and are part of the sheet member constituting the leg gather portion LG. In this case, the portion of the topsheet 12 disposed outside the standing start point 60ei functions as a rigidity-imparting means for imparting rigidity to the leg gather portion LG. Therefore, the leg gather portion LG is more likely to maintain a planar shape and is less likely to wrinkle, and when the diaper 1 is worn, it is difficult to form a gap between the leg gather portion LG and the wearer's skin, and it is easier to fit the leg gather portion LG to the leg circumferentially.

[0130] <Regarding the stretchability of the waist portions 20 and 30> Subsequently, the stretchability in the left and right directions of the front waist portion 20 and the rear waist portion 30 will be described. When the diaper 1 is worn, the front waist portion 20 and the rear waist portion 30 contract in the left and right directions to fit the wearer's waist circumference, thereby suppressing the absorbent body 10 from slipping downwards. Conversely, if the contraction force of the waist portions 20 and 30 is weak, the entire diaper 1 may slip downwards, which may deteriorate the fit of the leg gather portion LG in the wearer's leg circumference.

[0131] On the other hand, if the contraction force of the torso circumferential parts 20 and 30 is excessively high, the constriction on the wearer's torso becomes strong, which is likely to cause discomfort and uneasiness to the wearer. Further, since the lower end region of the front torso circumferential part 20 is located near the base of the wearer's leg when the diaper 1 is worn, if the contraction force at the lower end of the front torso circumferential part 20 is excessively high, it is likely to interfere with the movement of the wearer's leg. In this case, displacement of the front torso circumferential part 20 occurs due to the movement of the wearer's leg, which becomes a factor greatly deteriorating the fit of the torso circumferential parts 20 and the leg gather part LG.

[0132] Therefore, in the diaper 1 of the present embodiment, while ensuring an appropriate contraction force of the front torso circumferential part 20, it is made difficult to interfere with the movement of the leg during wearing, thereby improving the fit of the torso circumferential parts 20 and 30 and the leg gather part LG. Hereinafter, the contraction force of the front torso circumferential part 20 and the rear torso circumferential part 30 will be described. In the diaper 1, since the front torso circumferential part 20 and the rear torso circumferential part 30 have substantially the same structure as described above, hereinafter, basically, the front torso circumferential part 20 will be described, and the description of the rear torso circumferential part 30 will be omitted. However, if necessary, the rear torso circumferential part 30 may also be described.

[0133] FIG. 9 is a plan view showing the front torso circumferential part 20 and the absorbent body 10 in an extended state. In FIG. 9, when the front torso circumferential part 20 is equally divided into four regions in the vertical direction, the regions from the upper side in order are the first front torso circumferential region 20A1, the second front torso circumferential region 20A2, the third front torso circumferential region 20A3, and the fourth front torso circumferential region 20A4. Here, equally dividing the front torso circumferential part 20 into four regions in the vertical direction means that the region sandwiched in the vertical direction by a line connecting the upper ends 2et, 2et of a pair of side joining parts 2, 2 formed at both ends in the left-right direction of the front torso circumferential part 20 and a line connecting the lower ends 2eb, 2eb of the pair of side joining parts 2, 2 is equally divided into four regions in the vertical direction. Similarly, when the rear torso circumferential part 30 is equally divided into four regions in the vertical direction, the regions from the upper side in order are the first rear torso circumferential region 30A1, the second rear torso circumferential region 30A2, the third rear torso circumferential region 30A3, and the fourth rear torso circumferential region 30A4.

[0134] As described above, a plurality of waist circumferential elastic members 23, 23,... are attached to the front waist circumferential portion 20 in a state of extending in the left-right direction, thereby imparting elasticity (contractibility) in the left-right direction. At this time, for each region of the first to fourth front waist circumferential regions 20A1 to 20A4 of the front waist circumferential portion 20, by appropriately adjusting the magnitude of the expansion and contraction force (contraction force) exhibited by the waist circumferential elastic member 23, better fit can be achieved.

[0135] Specifically, in the front waist circumferential portion 20 of the diaper 1, the contraction force of the third front waist circumferential region 20A3 is made larger than that of the fourth front waist circumferential region 20A4. That is, the contraction force when the third front waist circumferential region 20A3 is extended to 0.9 times the length when extended most along the left-right direction and then returned to 0.7 times the length is made larger than the contraction force when the fourth front waist circumferential region 20A4 is extended to 0.9 times the length when extended most along the left-right direction and then returned to 0.7 times the length.

[0136] In the diaper 1, by widening (to 5 mm or more) the pitch (interval) of the LG elastic member 17 provided in the leg gather portion LG compared to conventional diapers, the surface pressure of the leg gather portion LG does not become excessively large, and it is possible to make it difficult for the wearer's leg to be chafed or turn red. On the other hand, since the surface pressure of the leg gather portion LG is lowered, there is a possibility that a gap will be generated between the leg gather portion LG and the wearer's skin when the wearer moves their leg during walking or the like. In contrast, by enhancing the fit of the front waist circumferential portion 20 and making it difficult for the front waist circumferential portion 20 to shift and fall from the wearer's body (abdomen) when wearing the diaper 1, it is possible to make it difficult for a gap to be generated between the leg gather portion LG and the wearer's skin. That is, even if the pitch of the LG elastic member is widened compared to conventional diapers and the surface pressure of the leg gather portion LG is reduced, by making it difficult for the front waist circumferential portion 20 to shift from the wearer's abdomen, it is possible to make it difficult for a gap to be generated between the leg gather portion LG and the wearer's skin.

[0137] At that time, in the front body circumference part 20, by making the contraction force of the third front body circumference area 20A3 larger than the contraction force of the fourth front body circumference area 20A4, the fit of the diaper 1 on the abdomen of the wearer can be further improved. FIG. 10 is a view showing the wearer wearing the diaper 1 as seen from the lateral direction.

[0138] The abdomen of a person (wearer) usually bulges more gradually toward the front (ventral side) from the chest to the waist, and the bulge becomes smaller around the lower abdomen. In the state of wearing the diaper 1, as shown in FIG. 10, the bulge of the wearer's abdomen is large at the positions of the first front body circumference area 20A1 and the second front body circumference area 20A2, and the bulge of the abdomen becomes smaller at the positions of the third front body circumference area 20A3 and the fourth front body circumference area 20A4. Also, when the wearer breathes, the abdomen bulges and collapses greatly at the positions of the first front body circumference area 20A1 and the second front body circumference area 20A2, while the movement of the abdomen is small at the positions of the third front body circumference area 20A3 and the fourth front body circumference area 20A4. Therefore, by increasing the contraction forces of the third front body circumference area 20A3 and the fourth front body circumference area 20A4 in the front body circumference part 20 of the diaper 1, it is difficult to cause discomfort to the wearer due to tightening, and the fit of the front body circumference part 20 can be improved.

[0139] However, since the lower end of the fourth front body circumferential region 20A4 forms a part of the leg opening LH of the diaper 1 (see FIG. 1), if the contraction force of the fourth front body circumferential region 20A4 is too large, it may interfere with the movement of the wearer's legs, resulting in a deterioration of the fit. In contrast, in the diaper 1, by making the contraction force of the fourth front body circumferential region 20A4 smaller than that of the third front body circumferential region 20A3, the lower end of the fourth front body circumferential region 20A4 (leg opening LH) is less likely to interfere with the movement of the wearer's legs. As a result, the front body circumferential portion 20 can easily fit to the wearer's abdomen without interfering with the movement of the wearer's body (leg movement and abdominal movement due to breathing). And, by enhancing the fit of the front body circumferential portion 20 and making it less likely to slip off, the wide leg gather portion LG can easily fit snugly around the wearer's calves.

[0140] Here, the contraction forces of the respective regions 20A1 to 20A4 of the front body circumferential portion 20 can be measured as follows according to the method described in FIG. 7. First, the absorbent main body 10 is peeled off from the front body circumferential portion 20 using a cold spray, preferably a dryer, and divided (cut) into four regions 20A1 to 20A4 shown in FIG. 9 to obtain four types of test pieces TP. When the body circumferential elastic member 23 is arranged on the boundary of the regions 20A1 to 20A4, the body circumferential elastic member 23 is included in the upper side (waist end side) region. Then, a tensile test is performed on each test piece TP in the same manner as in FIG. 7C. That is, both ends of the test piece TP in the left-right direction are clamped by the chuck of a tensile tester, and after being extended until the length in the left-right direction becomes 0.9 times the extended length, it is contracted until it reaches 0.7 times the length. This cycle is repeated twice, and at the time of contraction in the second cycle, the magnitude of the force (N) when the test piece TP is contracted until its length becomes 0.7 times the extended length is measured. Such measurements are repeated a predetermined number of times (for example, 3 times), and the average of the measured values is taken as the contraction force of the object to be measured (regions 20A1 to 20A4).

[0141] In the diaper 1, among the respective regions 20A1 to 20A4 of the front body circumferential portion 20, the contraction force of the third front body circumferential region 20A3 is the largest. In the state where the wearer wears the diaper 1, the portion where the third front body circumferential region 20A3 is located has a small protrusion of the abdomen and small fluctuations due to breathing or the like. Therefore, even if the contraction force of the third front body circumferential region 20A3 is increased, it is difficult to cause discomfort to the wearer. By firmly fitting the third front body circumferential region 20A3 to such a portion with small abdominal movement (fluctuation) and fixing the position, the entire front body circumferential portion 20 is less likely to shift and fall, and the fitting property of the front body circumferential portion 20 and the leg gather portion LG can be further enhanced.

[0142] Also, among the respective regions 20A1 to 20A4 of the front body circumferential portion 20, the total contraction force of the third front body circumferential region 20A3 and the fourth front body circumferential region 20A4 is larger than the total contraction force of the first front body circumferential region 20A1 and the second front body circumferential region 20A2. The upper regions (the first front body circumferential region 20A1 and the second front body circumferential region 20A2) of the front body circumferential portion 20 are located in portions where the protrusion and fluctuation of the wearer's abdomen are large. Therefore, if the tightening is excessively strong, it is likely to cause discomfort to the wearer. On the other hand, the lower regions (the third front body circumferential region 20A3 and the fourth front body circumferential region 20A4) in the vertical direction of the front body circumferential portion 20 are located in portions where the protrusion and fluctuation of the wearer's abdomen are small. Therefore, even if the tightening is stronger compared to the upper regions, it is difficult to cause discomfort to the wearer, and the fitting property can be efficiently enhanced.

[0143] In particular, infants assumed as the wearing target of the diaper 1 generally have a body type in which the abdomen is likely to be potbellied, and are also weak in abdominal tightening. Therefore, by making the contraction force in the upper half of the front body circumferential portion 20 smaller than the contraction force in the lower half, it is possible to enhance the fitting property for potbellied infants while ensuring safety during wearing.

[0144] In the front body circumference portion 20 of the diaper 1, the contraction force is adjusted so as to decrease in the order of the third front body circumference region 20A3, the fourth front body circumference region 20A4, the first front body circumference region 20A1, and the second front body circumference region 20A2. This makes it easier to achieve the good fit as described above.

[0145] Also, focusing on the rear body circumference portion 30, in the diaper 1, among the first rear body circumference region 30A1 to the fourth rear body circumference region 30A4, the contraction force of the third rear body circumference region 30A3 is the largest. That is, also in the rear body circumference portion 30, similar to the front body circumference portion 20, the contraction force of the third region (30A3) from the top when divided into four equal parts is the largest. As a result, by the third front body circumference region 20A3 and the third rear body circumference region 30A3 being linked in a ring shape, it becomes easier to apply a large contraction force along the body circumference. As described above, in the abdomen of the wearer, this region has a small bulge and small fluctuations due to breathing etc., so even if a strong tightening acts, it is difficult to cause discomfort to the wearer. Therefore, by strongly tightening the portion with small variations and weakening the tightening of the other portions, the diaper 1 can easily follow the movement of the wearer's body. Therefore, by maximizing the contraction force of the body circumference portions 20 and 30 in the said regions (20A3, 30A3), it becomes difficult for the entire body circumference portions 20 and 30 to be displaced, and the fit can be further improved without causing discomfort to the wearer.

[0146] On the other hand, in the rear body circumference portion 30, the contraction force of the second rear body circumference region 30A2 may be made the largest. In the back of the wearer, the region where the second rear body circumference region 30A2 hits is, as shown in FIG. 10, the portion where the constriction becomes large at the boundary between the back and the buttocks. Therefore, by maximizing the contraction force acting on the portion with a small bulge on the back of the wearer, it becomes easier to fix the position of the rear body circumference portion 30 on the back. As a result, it becomes easier for the front body circumference portion 20 and the rear body circumference portion 30 to be firmly fixed to the wearer's body circumference on both the front and back sides, the slippage of the body circumference portions 20 and 30 is suppressed, and the fit is improved.

[0147] FIG. 11 is a plan view showing the front body circumferential portion 20 in a natural state and the absorbent body 10. FIG. 11 shows a state when the front body circumferential portion 20 is changed from the extended state in FIG. 9 to the natural state. As shown in FIG. 11, in the diaper 1 in the natural state, the length W20A3 (the length of the shortest portion) in the left-right direction of the third front body circumferential region 20A3 is shorter than the length W20A4 (the length of the shortest portion) in the left-right direction of the fourth front body circumferential region 20A4. With such a configuration, in the third front body circumferential region 20A3 between the upper end and the lower end of the front body circumferential portion 20, a contraction folding start point is likely to be formed. As a result, the third front body circumferential region 20A3 can more easily enter the lower abdominal portion (the concave portion of the abdomen in FIG. 10) with a small protrusion on the ventral side of the wearer. Therefore, the front body circumferential portion 20 is less likely to slip off, and the fit can be improved.

[0148] Furthermore, in the natural state of FIG. 11, the average length in the left-right direction of the third front body circumferential region 20A3 and the fourth front body circumferential region 20A4 is shorter than the average length in the left-right direction of the first front body circumferential region 20A1 and the second front body circumferential region 20A2. With such a configuration, in the upper half region (20A1, 20A2) of the front body circumferential portion 20 where the abdominal movement (displacement) is large, the amount of contraction in the left-right direction becomes small, so that the front body circumferential portion 20 is less likely to interfere with the movement of the wearer's abdomen and is less likely to cause discomfort to the wearer. On the other hand, in the lower half region (20A3, 20A4) of the front body circumferential portion 20 where the abdominal movement (displacement) is small, the amount of contraction in the left-right direction becomes large, so that the front body circumferential portion 20 is likely to be fixed to the concave portion of the lower abdomen of the wearer and is less likely to be displaced. Therefore, the fit of the front body circumferential portion 20 can be improved.

[0149] Further, the front body circumferential portion 20 and the absorbent main body 10 are joined to each other by a main body joining portion 70. The main body joining portion 70 is formed by applying an adhesive such as a hot melt adhesive to a plurality of strip-shaped regions extending in the vertical direction shown by the hatched portion in FIG. 9. In the vertical direction, the upper end 70et of the main body joining portion 70 is located above the upper end 20lc of the third front body circumferential region 20A3. That is, in the vertical direction, the entire third front body circumferential region 20A3 is joined to the absorbent main body 10 via the main body joining portion 70. Thereby, the absorbent main body 10 is pressed against the wearer's skin side by the large contraction force of the third front body circumferential region 20A3, and the heavy absorbent main body 10 is less likely to slip downwards. Therefore, the fit of the absorbent main body 10 is further improved, and it is easier to suppress the leg gather portion LG from shrinking inward.

[0150] Also, in the vertical direction, the upper end 11et of the absorber 11 is located below the upper end 20lc of the third front body circumferential region 20A3. That is, in the vertical direction, there is a portion where the third front body circumferential region 20A3 and the absorber 11 do not overlap. In the non-overlapping portion, since the contraction force of the third front body circumferential region 20A3 is hardly inhibited by the highly rigid absorber 11, a large contraction force can be applied to the recess in the wearer's lower abdomen. Thereby, the fit of the absorbent main body 10 is further improved, and it is easier to suppress the leg gather portion LG from shrinking inward.

[0151] Further, it is preferable that the average pitch in the vertical direction of the waist elastic members 23, 23... disposed in the third front waist region 20A3 is smaller than the average pitch in the horizontal direction of the LG elastic members 17, 17... disposed in the leg gather portion LG. When the pitch of the LG elastic members 17 becomes relatively large, it is difficult for the surface pressure of the leg gather portion LG to become excessively large, and it is difficult for linear marks of the LG elastic members 17 to be left on the skin of the wearer. Note that when the pitch of the LG elastic members 17 is widened, usually, the leg gather portion LG tends to shrink (see FIG. 5B). However, in the diaper 1 of the present embodiment, by appropriately adjusting the contraction force of the LG elastic members 17, it is possible to suppress the shrinkage of the leg gather elastic members 17.

[0152] Further, when viewed in the thickness direction, there is a portion where the waist elastic member 23 disposed in the front waist portion 20 and the LG elastic member 17 disposed in the leg gather portion LG intersect (see FIG. 9). Thereby, the contraction force of the waist elastic member 23 and the contraction force of the LG elastic member 17 are interlocked, and the LG elastic member 17 is easily pulled upward, so that the entire diaper 1 is difficult to hang downward, and the deterioration of the fit of the front waist portion 20 and the leg gather portion LG is suppressed.

[0153] Further, regarding the rear waist portion 30, when viewed in the thickness direction, the waist elastic member 33 disposed in the rear waist portion 30 and the LG elastic member 17 disposed in the leg gather portion LG may intersect. Similar to the ventral side, on the dorsal side, the contraction force of the waist elastic member 33 and the contraction force of the LG elastic member 17 are interlocked, so that the diaper 1 is difficult to hang downward, and the deterioration of the fit on the dorsal side is suppressed. Note that if there is a portion where the waist elastic members 23, 33 and the LG elastic member 17 intersect at least on either the front side (ventral side) or the rear side (dorsal side), the above-described effects can be obtained.

[0154] ===Other Embodiments=== The embodiments of the present invention have been described above. However, the above embodiments are for facilitating the understanding of the present invention and are not for limiting the interpretation of the present invention. Further, the present invention can be modified and improved without departing from its gist, and it goes without saying that equivalents of the present invention are included therein.

[0155] In the above-described embodiment, the circumferential elastic member 23(33) such as thread rubber imparts elasticity along the left-right direction to the circumferential portion 20(30). However, elasticity may be imparted by other elastic members. For example, an elastic sheet (not shown) that expands and contracts in the left-right direction may be provided so as to cover the upper end portion (near the first front circumferential region 20A1 in FIG. 9) of the front circumferential portion 20, thereby imparting elasticity.

[0156] In the above-described embodiment, the outer sheet 14 is folded back at the outer ends 10es in the left-right direction of the absorbent body 10, and the leg gather portion LG and the leak-proof wall portion LSG are formed by the folded-back portion 14f (see FIG. 6 etc.). However, this is not the only case. For example, the sheet member corresponding to the folded-back portion 14f may be constituted by a separate sheet member (LG non-woven fabric) different from the outer sheet 14. In this case, the leg gather portion LG is constituted by attaching the LG elastic member in an extended state between the thickness directions of the separate sheet member (LG non-woven fabric) and the outer sheet 14. Further, a part of the LG non-woven fabric may be provided so as to cover the outer ends in the left-right direction of the outer sheet 14 from the non-skin side, and the LG elastic member may be provided on the non-skin side (skin side of the LG non-woven fabric) of the outer sheet 14.

Explanation of Reference Numerals

[0157] 1 Diaper (pant-type absorbent article), 2 Side joint portion, 2et Upper end, 2eb Lower end, 10 Absorbent body, 10es Outer end (left-right direction), 11 Absorbent body, 11es Outer end (left-right direction), 11et Upper end, 11a Absorbent core, 11b Core wrap sheet, 11c Constricted portion, 12 Top sheet, 13 Leak-proof film, 14 Outer wrapper sheet, 14f Folded-back portion, 14s Upright portion, 14st Tip, 17 LG elastic member (leg gather elastic member), 17a Inner LG elastic member, 17b Intermediate LG elastic member, 17c Outer LG elastic member, 18 Inseam elastic member, 19 Leak-proof wall elastic member, 20 Front body circumference portion, 20A1 First front body circumference region, 20A2 Second front body circumference region, 20A3 Third front body circumference region, 20A4 Fourth front body circumference region, 21 Body circumference sheet, 23 Body circumference elastic member, 25 Skin-side sheet, 30 Rear body circumference portion, 30A1 First rear body circumference region, 30A2 Second rear body circumference region, 30A3 Third rear body circumference region, 30A4 Fourth rear body circumference region, 31 Body circumference sheet, 33 Body circumference elastic member, 35 Skin-side sheet, 50 LG joint portion (leg gather joint portion), 51 First LG joint portion, 51ei Inner end (starting point of erection), 52 Second LG joint portion, 53 Third LG joint portion, 54 Fourth LG joint portion, 60 Welded portion, 60ei Starting point of erection, 61 First welding pattern, 62 Second welding pattern, 70 Body joint portion, BH Body circumference opening, LH Leg circumference opening, LG Leg gather portion, LSG Leak-proof wall portion, ER Leg gather elastic region

Claims

1. having a vertical direction and a horizontal direction that intersect each other, having an absorbent body, a front body waist portion, and a rear body waist portion, the front body waist portion and the rear body waist portion are joined to each other by a pair of side joining portions at both end portions in the horizontal direction, a pair of leak-proof wall portions and a pair of leg gather portions are respectively provided on both sides of the absorbent body in the horizontal direction, in the leg gather portion, three or more leg gather elastic members that stretch along the longitudinal direction of the absorbent body are arranged at intervals of 5 mm or more in the horizontal direction, which is a pants-type absorbent article, the leg gather elastic member has a first leg gather elastic member and a second leg gather elastic member arranged outside the first leg gather elastic member in the horizontal direction, the contraction force of the first leg gather elastic member when it is extended to 0.9 times its length when the first leg gather elastic member is stretched most along the longitudinal direction and then returned to 0.7 times its length, is greater than the contraction force of the second leg gather elastic member when the second leg gather elastic member is extended to 0.9 times its length when the second leg gather elastic member is stretched most along the longitudinal direction and then returned to 0.7 times its length, in the region of the leg gather portion from the outermost end in the horizontal direction to the leg gather elastic member arranged most inwardly, there is a rigidity imparting means for imparting rigidity to the leg gather portion, at least a part of the rigidity imparting means does not overlap with the leg gather elastic member when viewed in the thickness direction, and has a portion continuous in the longitudinal direction in a region below the lower end of the side joining portion, which is characterized by a pants-type absorbent article.

2. The pants-type absorbent article according to claim 1, among the two leg gather elastic members arranged adjacent to each other in the horizontal direction, the contraction force when the leg gather elastic member arranged inside in the horizontal direction is extended to 0.9 times its length when stretched most along the longitudinal direction and then returned to 0.7 times its length, is equal to or greater than the contraction force when the leg gather elastic member arranged outside in the horizontal direction is extended to 0.9 times its length when stretched most along the longitudinal direction and then returned to 0.7 times its length, which is characterized by a pants-type absorbent article.

3. The pant-type absorbent article according to claim 1 or 2, wherein among the two leg gather elastic members arranged adjacent to each other in the left-right direction, for the leg gather elastic member arranged on the inner side in the left-right direction, the value obtained by dividing the length in the natural state by the length when stretched most along the longitudinal direction is not more than the value obtained by dividing the length in the natural state by the length when stretched most along the longitudinal direction for the leg gather elastic member arranged on the outer side in the left-right direction. The pant-type absorbent article is characterized by this.

4. The pant-type absorbent article according to claim 1 or 2, wherein among the two leg gather elastic members arranged adjacent to each other in the left-right direction, the cross-sectional area in the natural state of the leg gather elastic member arranged on the inner side in the left-right direction is not less than the cross-sectional area in the natural state of the leg gather elastic member arranged on the outer side in the left-right direction. The pant-type absorbent article is characterized by this.

5. The pant-type absorbent article according to claim 1 or 2, wherein in the left-right direction, when the region from the outermost end of the leg gather portion to the leg gather elastic member arranged most inward is defined as the leg gather elastic region, the length in the left-right direction of the leg gather elastic region in the stretched state is not less than half of the length in the left-right direction of the leg gather portion in the stretched state, and when the leg gather elastic region is evenly divided in the left-right direction by the number of leg gather elastic members arranged in the leg gather elastic region, each divided region has a leg gather elastic member arranged therein. The pant-type absorbent article is characterized by this.

6. The pant-type absorbent article according to claim 5, wherein the rigidity imparting means is provided in each region obtained by evenly dividing the leg gather elastic region in the left-right direction. The pant-type absorbent article is characterized by this.

7. The pant-type absorbent article according to claim 5, wherein when viewed in the thickness direction, the rigidity imparting means is provided between the two leg gather elastic members arranged adjacent to each other in the left-right direction. The pant-type absorbent article is characterized by this.

8. The pant-type absorbent article according to claim 1 or 2, wherein The value obtained by dividing the contraction force when the leg gather part is extended to 0.9 times its length along the longitudinal direction and then returned to 0.7 times its length by the width of the leg gather part is not more than the value obtained by dividing the contraction force when the leakage-preventing wall part is extended to 0.9 times its length along the longitudinal direction and then returned to 0.7 times its length by the width of the leakage-preventing wall part. A pant-type absorbent article characterized by this. **Claim 9** The pant-type absorbent article according to claim 1 or 2, wherein the leg gather part has at least two sheet members laminated in the thickness direction, and a leg gather elastic member is provided between the laminated sheet members. The pant-type absorbent article, wherein the rigidity imparting means imparts rigidity to the leg gather part by joining the laminated sheet members to each other. **Claim 10** The pant-type absorbent article according to claim 9, wherein the rigidity imparting means imparts rigidity to the leg gather part by joining the laminated sheet members to each other with an adhesive. A pant-type absorbent article characterized by this. **Claim 11** The pant-type absorbent article according to claim 1 or 2, when, in the left-right direction, the region from the outermost end of the leg gather part in the extended state to the leg gather elastic member arranged most inward is defined as the leg gather elastic region, the rigidity imparting means is provided in at least half of the area of the leg gather elastic region. A pant-type absorbent article characterized by this. **Claim 12** The pant-type absorbent article according to claim 1 or 2, wherein the absorbent main body has a liquid-absorbent absorber, a liquid-impermeable sheet is provided on the non-skin side of the absorber, and in the left-right direction, the outer end of the liquid-impermeable sheet is located between the leg gather elastic member arranged most outward and the leg gather elastic member arranged second from the outside. A pant-type absorbent article characterized by this. **Claim 13** The pant-type absorbent article according to claim 1 or 2, wherein in the left-right direction, the rigidity imparting means is not provided outside the leg gather elastic member arranged most outward. A pant-type absorbent article characterized by this. **Claim 14** The pant-type absorbent article according to claim 1 or 2, The shortest distance from the outer end in the left - right direction of the leg gather part in the extended state to the standing - start point of the leakage - preventing wall part is not less than the shortest distance from the standing - start point of the leakage - preventing wall part to the tip of the leakage - preventing wall part in the extended state. A pant - type absorbent article characterized by this.

15. The pant - type absorbent article according to claim 1 or 2, wherein the absorbent main body has a liquid - absorbent absorber, and in the left - right direction, in the region between the outer end of the absorber and the standing - start point of the leakage - preventing wall part, it has an inseam elastic member that expands and contracts along the longitudinal direction of the absorbent main body. A pant - type absorbent article characterized by this.

16. The pant - type absorbent article according to claim 1 or 2, wherein the absorbent main body has a liquid - absorbent absorber, a topsheet is provided on the skin - side of the absorber, and at least a part of the topsheet is disposed outside the standing - start point of the leakage - preventing wall part in the left - right direction. A pant - type absorbent article characterized by this.

17. The pant - type absorbent article according to claim 1 or 2, wherein the front - side body - surrounding part and the rear - side body - surrounding part have a body - surrounding elastic member that expands and contracts in the left - right direction, and when viewed in the thickness direction, at least one of the front - side body - surrounding part and the rear - side body - surrounding part has a portion where the body - surrounding elastic member and the leg - gather elastic member intersect. A pant - type absorbent article characterized by this.

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