Underpants type absorbent article

Abstract

To provide an underpants type absorbent article which has a waist part and leg gatherings with high fitness.SOLUTION: An underpants type absorbent article (1) comprises: an absorbent main body (10); and a pair of leg gathering parts (LG). The leg gathering part (LG) comprises three or more leg gathering elastic members (17) which extend and shrink in a longitudinal direction and are 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 second leg gathering elastic members (17b, 17c) arranged outside in the lateral direction. When a front side waist part (20) is divided into equal four parts in a vertical direction, an area which is a third area from the top is a third front side waist area (20A3), and an area which is a fourth area from the top is a fourth front side waist area (20A4), the shrinkage force of the third front side waist area (20A3) is greater than that of the fourth front side waist area (20A4).SELECTED DRAWING: Figure 9

Description

Technical Field

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

Background Art

[0002] Conventionally, in a pant-type diaper or the like having a leg gather (LG) that can expand and contract along the leg opening, by widening the width of the leg gather, a technique for improving the fit of the leg cuffs while suppressing lateral leakage of excrement such as urine is known. For example, Patent Document 1 discloses a pant-type diaper including a pair of extending portions (corresponding to leg gathers) extending outward in the width direction from both side edges of an absorber, and by making the length of the extending portion in the width direction larger than the height of the leak-proof cuff portion, a pant-type diaper capable of fitting the extending portion (leg gather) widely around the legs of the wearer is disclosed.

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 expand and contract along the longitudinal direction (the longitudinal direction of the absorber) of the extending portion (leg gather) impart elasticity to the leg gather portion. However, if the fit at the waist portion is poor, the entire diaper is likely to slip off the wearer's body, a gap may occur between the leg gather and the wearer's leg, or the leg gather may interfere with the movement of the wearer's leg, resulting in a deterioration in the fit of the leg gather.

[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 highly fitting waist portion and leg gathers.

Means for Solving the Problems

[0006] The main invention for achieving the above object is a pants-type absorbent article having a vertical direction and a horizontal direction intersecting with each other, an absorbent body, a front body surrounding portion, and a rear body surrounding portion. The front body surrounding portion and the rear body surrounding portion are joined to each other by a pair of side joining portions at both end portions in the horizontal direction. On both sides of the absorbent body in the horizontal direction, a pair of leak-proof wall portions and a pair of leg gather portions are respectively provided. 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 surrounding portion and the rear body surrounding portion have elasticity along the horizontal direction. When the third region from the top and the fourth region from the top are defined as the third front body surrounding region and the fourth front body surrounding region respectively when the front body surrounding portion is equally divided into four in the vertical direction between the upper end and the lower end of the side joining portion, the contraction force of the third front body surrounding 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 surrounding region when the fourth front body surrounding region is extended to 0.9 times its length when extended along the horizontal direction and then returned to 0.7 times its length. This is a pants-type absorbent article characterized by the above. Other features of the present invention will be clarified by the description in this specification and the attached drawings.

Effect of the Invention

[0007] According to the present invention, it is possible 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.

Brief Description of the Drawings

[0008]

Figure 1

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Figure 8

Figure 9

Figure 10

Figure 11

Modes 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 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 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 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 disposed 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 to the maximum 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 extended to the maximum 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 upper third region from the top and the fourth region from the top are defined as the third front body circumferential region and the fourth front body circumferential region, respectively, when the front body circumferential portion is equally divided into four in the vertical direction between the upper end and the lower end of the side joining portion, the contraction force of the third front body circumferential region when it is extended to 0.9 times its length when extended to the maximum 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 to the maximum along the horizontal direction and then returned to 0.7 times its length.

[0011] According to the pant-type absorbent article of Mode 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 the surface shape. As a result, a pant-type absorbent article having a leg gather part with a surface pressure that is not excessively high and that is difficult to wrinkle inward is realized. Further, 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 risk of lateral leakage of excrement or the like.

[0012] (Mode 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 to the maximum 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 to the maximum along the longitudinal direction and then returned to 0.7 times the length. The pant-type absorbent article according to Mode 1.

[0013] According to the pant-type absorbent article of Mode 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, while suppressing the surface pressure of the leg gather part from becoming excessively high, the fitting property can be improved along the leg bending shape of the wearer.

[0014] (Mode 3) 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 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 part 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 part from becoming excessively high, the fitness can be enhanced along the leg - bending shape of the wearer.

[0016] (Aspect 4) 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 greater than or equal to 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 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 part. 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 part, 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) In the aspect according to any one of Aspects 1 to 4, the shortest distance from the outer end in the left-right direction of the leg gather portion in the extended state to the starting point of the standing-up of the leakage-preventing wall portion is equal to or greater than the shortest distance from the starting point of the standing-up of the leakage-preventing wall portion to the tip of the leakage-preventing wall portion in the extended state. 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, even if the leakage-preventing wall portion falls outward in the left-right direction from the standing state during wearing, it is possible to suppress the fallen leakage-preventing wall portion from protruding outside 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 movement in a planar manner.

[0020] (Aspect 6) 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 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, for each of the first front body circumferential region to the fourth front body circumferential region, when 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 the largest in the third front body circumferential region. The pant-type absorbent article according to any one of Aspects 1 to 5.

[0021] According to the pant-type absorbent article of Aspect 6, the portion where the third front body circumferential region abuts during wearing 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 is increased, it is difficult to cause discomfort to the wearer. And by firmly fitting the third front body circumferential region to the portion with small movement (fluctuation) of the abdomen and fixing the position, the entire front body circumferential portion is less likely to shift and fall, and the fitting property of the front body circumferential portion and the leg gather portion can be further improved.

[0022] (Aspect 7) The total contracting force of the third front waist region and the fourth front waist region is greater than the total contracting force of the first front waist region and the second front waist region, the pant-type absorbent article according to any one of Aspects 1 to 6.

[0023] According to the pant-type absorbent article of Aspect 7, since the upper regions (the first front waist region 20 and the second front waist region) of the front waist part are located in the parts of the wearer's abdomen with 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 waist region and the fourth front waist region) of the front waist part are located in the parts of the wearer's abdomen with small protrusions and fluctuations, by strengthening the tightening compared with the upper regions, it is difficult to cause discomfort to the wearer, and the fit can be efficiently improved. In particular, it is suitable when the wearer is an infant whose abdomen is likely to be pot-bellied, because the safety can be ensured and the fit can be improved.

[0024] (Aspect 8) When the rear waist part is equally divided into four 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 waist region, the second region from the upper side is the second rear waist region, the third region from the upper side is the third rear waist region, and the fourth region from the upper side is the fourth rear waist region, for each of the first rear waist region to the fourth rear waist region, when it is extended to 0.9 times the length when it is most extended along the left-right direction and then returned to 0.7 times the length, the magnitude of the contracting force of the third rear waist region is the largest, the pant-type absorbent article according to any one of Aspects 1 to 7.

[0025] According to the pant-type absorbent article of Aspect 8, in the region of the wearer's abdomen where the protrusion is small and the fluctuation due to breathing etc. is small, due to the interlocking of the annularly connected third front waist region and the third rear waist region, it becomes easy to act a large contracting force along the waist. Therefore, in this region, the waist part is less likely to be displaced, and the fit can be further improved without causing discomfort to the wearer.

[0026] (Aspect 9) When the rear body circumferential part is equally divided into four 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 of the second rear body circumferential region is the largest. The pant - type absorbent article according to any one of Aspects 1 to 7.

[0027] According to the pant - type absorbent article of Aspect 9, on the back side of the wearer, 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.

[0028] (Aspect 10) 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 pant - type absorbent article according to any one of Aspects 1 to 9.

[0029] According to the pant - type absorbent article of Aspect 10, 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 lower abdomen part of the wearer, so that the front body circumferential part is difficult to slip off and the fit can be improved.

[0030] (Aspect 11) 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 joining part, 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 1 to 10.

[0031] According to the pant-type absorbent article of aspect 11, in the upper half region of the front body circumferential part where the abdominal fluctuations are large, the amount of contraction 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 amount of contraction 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.

[0032] (Aspect 12) Having a main body joining part that joins the absorbent main body and the front body circumferential part, in the vertical direction, the upper end of the main body joining 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 1 to 11.

[0033] According to the pant-type absorbent article of aspect 12, in the vertical direction, since the entire third front body circumferential region is joined to the absorbent main body via the main body joining 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.

[0034] (Aspect 13) The absorbent 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 1 to 12.

[0035] According to the pant-type absorbent article of Aspect 13, in a portion where the third front torso circumferential region and the absorber do not overlap, the contraction force of the third front torso circumferential region is hardly inhibited by the highly rigid absorber, so a large contraction force can be applied to the recess of the wearer's lower abdomen. Thereby, the fit of the absorbent body is further improved, and it becomes easier to suppress the leg gather portion from being drawn inward.

[0036] (Aspect 14) The front torso circumferential portion has a plurality of torso elastic members that expand and contract in the left-right direction at intervals 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 elastic member disposed in the third front torso circumferential region, 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, 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 marks of the LG elastic member to be left on the skin of the wearer.

[0038] (Aspect 15) In the region of the leg gather portion from the outermost end in the left-right direction to the leg gather elastic member disposed most inwardly, there is a rigidity imparting means for imparting rigidity to the leg gather portion, and 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 joint portion, 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, the rigidity is increased over a wide range of the leg gather portion by the rigidity imparting means, and the leg gather portion is likely to maintain its planar shape. As a result, a pant-type absorbent article is realized that has a leg gather portion with a not overly high surface pressure, is less likely to wrinkle inwardly, and has high fit. In addition, since the leg gather portion is likely to fit the wearer's leg in a planar manner, it is possible to make it difficult for the user to be reminded of the risk of lateral leakage of excrement or the like.

[0040] (Aspect 16) The leg gather portion has at least two sheet members laminated in the thickness direction, and the 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 Aspect 15.

[0041] According to the pant-type absorbent article of Aspect 16, in the leg gather portion, the rigidity is increased by joining the sheet members laminated in the thickness direction to each other, and the sheet members constituting the leg gather portion are likely to be maintained in a planar shape. As a result, it is less likely for the leg gather portion to wrinkle. In addition, since the joint portion itself (for example, a welded portion or an adhesive portion) has rigidity, it is easier to ensure the rigidity of the leg gather portion.

[0042] (Aspect 17) The front body circumference portion and the rear body circumference portion have a body circumference elastic member that expands and contracts in the left-right direction, and when viewed in the thickness direction, at least one of the front body circumference portion and the rear body circumference portion has a portion where the body circumference elastic member and the leg gather elastic member intersect. The pant-type absorbent article according to Aspect 1 or 2.

[0043] According to the pant-type absorbent article of Aspect 17, the contraction force of the waist elastic member and the contraction force of the LG elastic member are interlocked, making it easier for the LG elastic member to be pulled upward. As a result, the entire pant-type absorbent article is less likely to sag downward, and deterioration of the fit of the waist portion and the leg gathers is suppressed. (Aspect 18) When the region from the outermost end of the leg gathers to the innermost leg gather elastic member disposed 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, and when the leg gather elastic region is equally divided in the left-right direction by the number of leg gather elastic members disposed in the leg gather elastic region, each divided region has a leg gather elastic member disposed therein. The pant-type absorbent article according to Aspects 15 to 17.

[0044] According to the pant-type absorbent article of Aspect 18, since the LG elastic members are evenly disposed in the leg gather portion, it is difficult for a local rigidity difference to occur, and it becomes easier to maintain the surface shape. In addition, since local pressure is less likely to be applied to the wearer's calf portion, it is possible to suppress skin chafing and reddening.

[0045] (Aspect 19) When the region from the outermost end of the leg gathers to the innermost leg gather elastic member disposed 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, and when the leg gather elastic region is equally divided in the left-right direction by the number of leg gather elastic members disposed in the leg gather elastic region, each region obtained by equally dividing the leg gather elastic region in the left-right direction is provided with the rigidity imparting means. The pant-type absorbent article according to Aspects 15 to 18.

[0046] According to the pant-type absorbent article of Aspect 19, in the leg gather elastic region, since the rigidity is increased for each region where the contraction force of the LG elastic member acts, the puckering etc. of the leg gather part is suppressed, and it becomes easier to maintain the surface shape.

[0047] (Aspect 20) The pant-type absorbent article according to any one of Aspects 15 to 19, wherein the rigidity imparting means is provided between the two leg gather elastic members arranged adjacent to each other in the left-right direction when viewed in the thickness direction.

[0048] According to the pant-type absorbent article of Aspect 20, since the rigidity is increased in the region between the two adjacent LG elastic members by the rigidity imparting means, it becomes difficult to form a bending starting point between the LG elastic members, and thus the puckering of the leg gather part is more easily suppressed.

[0049] (Aspect 21) The pant-type absorbent article according to any one of Aspects 15 to 20, wherein the rigidity imparting means is provided, and the value obtained by dividing the contraction force when the leg gather part is extended to 0.9 times the length when it is most extended in the longitudinal direction and then returned to 0.7 times the length by the width of the leg gather part is less than or equal to the value obtained by dividing the contraction force when the leakage-preventing wall part is extended to 0.9 times the length when it is most extended in the longitudinal direction and then returned to 0.7 times the length by the width of the leakage-preventing wall part.

[0050] According to the pant-type absorbent article of Aspect 21, since the surface pressure of the leg gather part becomes relatively small compared to the case where the contraction force per unit width of the leg gather part is larger than the contraction force per unit width of the leakage-preventing wall, it is possible to make it difficult to cause swelling or redness in the wearer's leg cuffs during wearing. (Aspect 22) The pant-type absorbent article according to any one of Aspects 15 to 21, wherein the rigidity imparting means imparts rigidity to the leg gather part by joining the laminated sheet members with an adhesive.

[0051] According to the pant-type absorbent article of Aspect 22, the rigidity of the leg gather portion is increased, the sheet member constituting the leg gather portion is easily maintained in a flat shape, and it is difficult for the leg gather portion to wrinkle. Further, since the adhesive such as a hot melt adhesive is solidified at room temperature, the adhesive itself has rigidity, and it is easier to secure the rigidity of the leg gather portion.

[0052] (Aspect 23) In the left-right direction, when the region from the outermost end of the leg gather portion in the extended state to the innermost leg gather elastic member is defined as the leg gather elastic region, the rigidity imparting means is provided in an area of at least half of the area of the leg gather elastic region. The pant-type absorbent article according to any one of Aspects 15 to 22.

[0053] According to the pant-type absorbent article of Aspect 23, since more than half of the leg gather elastic region is increased 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.

[0054] (Aspect 24) The absorbent main 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 15 to 23.

[0055] According to the pant-type absorbent article of Aspect 24, 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 planar 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 skin of the wearer, it is difficult to cause discomfort or unpleasantness to the wearer.

[0056] (Aspect 25) In the left - right direction, outside the outermost - arranged leg gather elastic member, the rigidity - imparting means is not provided, and the pant - type absorbent article according to any one of Aspects 15 to 24.

[0057] According to the pant - type absorbent article of Aspect 25, 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 discomfort or a sense of unease to the wearer.

[0058] (Aspect 26) 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 starting point of the standing - up of the leakage - preventing wall portion, there is a crotch elastic member that stretches along the longitudinal direction of the absorbent main body, and the pant - type absorbent article according to any one of Aspects 15 to 25.

[0059] According to the pant - type absorbent article of Aspect 26, 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. Also, 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.

[0060] (Aspect 27) The absorbent main body has a liquid - absorbent absorber, and a topsheet is provided on the skin side of the absorber, and at least a part of the topsheet is arranged outside the starting point of the standing - up of the leakage - preventing wall portion in the left - right direction, and the pant - type absorbent article according to any one of Aspects 15 to 26.

[0061] According to the pant-type absorbent article of Mode 27, 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 is likely to maintain a planar shape and is less likely to wrinkle. As a result, when worn, it is difficult to form a gap between the leg gather portion and the wearer's skin, and the leg gather portion is likely to fit smoothly around the leg.

[0062] ===Embodiment=== As the pant-type absorbent article according to the present embodiment, a 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.

[0063] <Configuration of Disposable Diaper 1> FIG. 1 is a schematic perspective view of the disposable diaper 1. FIG. 2 is a plan view of the diaper 1 in a deployed and extended state. FIG. 3 is a schematic cross-sectional view taken along the line A-A in FIG. 2.

[0064] In the pant-type state shown in FIG. 1, the diaper 1 has vertical, horizontal, and front-rear directions that intersect 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. Further, 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 in contact with the wearer's body (skin) in the thickness direction is referred to as the skin side, and the side not in contact with the wearer's body (skin) is referred to as the non-skin side.

[0065] In addition, 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 and the waist elastic members 23 and 33 described later). Specifically, it means a state in which each member constituting the diaper 1 (for example, the absorbent body 10 and the waist portions 20 and 30 described later) is extended until the dimensions thereof coincide with or are close to the dimensions of the member alone.

[0066] On the one hand, the state when the diaper 1 is left for a predetermined time is called the "natural state". For example, the diaper 1 in the product state is taken out of the package, and the waist portions 20 and 30 are pulled to both outer sides in the left - right direction to be in the "extended state". After maintaining 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 - placed state is defined as the natural state.

[0067] The diaper 1 has an absorbent main body 10, a front waist portion 20, and a rear waist portion 30, which are three members in a rectangular shape in plan view. When the diaper 1 is worn, the front waist portion 20 (ventral waist portion) is applied to the ventral part of the wearer, and the rear waist portion 30 (dorsal waist portion) is applied to the dorsal part of the wearer.

[0068] In the unfolded diaper 1 shown in FIG. 2, the front waist portion 20 and the rear waist portion 30 are arranged such that their longitudinal directions are along the left - right direction of the diaper 1. And, one end (front side) of the longitudinal direction of the absorbent main body 10 is joined to the central portion of the front waist portion 20 in the left - right direction, and the other end (rear side) of the longitudinal direction of the absorbent main body 10 is joined to the central portion of the rear waist portion 30 in the left - right direction.

[0069] Also, in the unfolded diaper 1 shown in FIG. 2, the absorbent main 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 main body 10 is along the up - down direction of the diaper 1. The front waist portion 20 and the rear waist 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 pant - type state (see FIG. 1) having a waist opening BH and a pair of leg 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 pant - type diaper 1.

[0070] (Absorbent main body 10) FIG. 4 is a plan view and a cross-sectional view of the absorbent body 10 in an extended 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 leakage-preventing film 13 disposed closer to the non-skin side than the absorber 11, and an outer packaging sheet 14 disposed closer to the non-skin side than the leakage-preventing film 13 and forming the exterior of the absorbent body 10. Further, on both sides in the left-right direction of the absorbent body 10, a pair of leakage-preventing wall portions LSG and leg gather portions LG are provided respectively.

[0071] The absorber 11 has an absorbent core 11a that absorbs and holds excreted fluids 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 in which liquid-absorbent fibers such as pulp containing a superabsorbent polymer (SAP) are formed into a predetermined shape. Alternatively, a so-called SAP sheet in which SAP particles are fixed to each other without containing liquid-absorbent fibers and formed into a flat plate shape 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.

[0072] 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, the length of which in the left-right direction is shorter (the width is narrower) 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, and due to the shorter length (narrower width) of the absorbent core 11a in the left-right direction at the constricted portion 11c, the absorber 11 is more likely to fit into the crotch of the wearer. 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.

[0073] The topsheet 12 is a liquid-permeable sheet member that covers the absorber 11 from the skin side. For example, a hydrophilic air-through nonwoven fabric, a spunbond nonwoven fabric, or the like 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. Further, a second sheet (not shown) equivalent to the topsheet 12 may be provided between the topsheet 12 and the absorber 11.

[0074] 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.

[0075] The outer sheet 14 is provided on the outermost non-skin side of the absorbent body 10 and is a sheet member that constitutes the exterior of the absorbent body 10. For example, an air-through nonwoven fabric, a spunbond nonwoven fabric, or the like can be used.

[0076] The outer sheet 14 extends outward in the left-right direction beyond the outer ends 11es, 11es of the absorber 11. The extended portion is folded back to the inner side in the left-right direction and 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 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 sheet 14 are joined by the first LG joining portion 51 to the fourth LG joining portion 54 in a state where the leak-proof film 13 is sandwiched therebetween in the thickness direction.

[0077] In addition, between the outer packaging sheet 14 forming the leg gather portion LG and the thickness direction of the folded-back portion 14f, 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, stretchability along the longitudinal direction (vertical 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 in the left-right direction of the absorbent body 10 as shown in FIG. 1.

[0078] In the present embodiment, three LG elastic members 17 are provided for 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 to 17c exhibits stretchability 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.

[0079] Also, as shown in FIG. 4, in the left-right direction, a crotch elastic member 18 such as thread rubber is provided in a state of being stretched in the longitudinal direction, inside the LG elastic member 17 (inner LG elastic member 17a) and outside the left-right direction outer ends 11es of the absorber 11. The crotch elastic member 18 exhibits elasticity at least in the portion shown by the solid line in the plan view of FIG. 4. When the diaper 1 is worn, the leg gather portion LG and the absorber 11 are pushed upward toward the wearer's skin side by the elasticity exhibited by the crotch elastic member 18. As a result, the leg gather portion LG and the absorber 11 can be more easily fitted to the wearer's leg bend and crotch portion, and lateral leakage of excrement (such as urine) can be effectively suppressed.

[0080] Also, as shown in FIG. 2, a part of the crotch elastic member 18 has a portion overlapping with the abdominal body circumference elastic member 23 and the dorsal body circumference elastic member 33 in the thickness direction. Thereby, the stretching force along the longitudinal direction by the crotch elastic member 18 and the stretching force along the left-right direction by the body circumference elastic members 23 and 33 are more likely to be interlocked, and the fitting property can be further improved. However, the crotch elastic member 18 may intersect only with either one of the body circumference elastic members 23 and 33 (either the abdominal side or the dorsal side), or may not intersect with either of the body circumference elastic members 23 and 33.

[0081] Also, a part of the folded-back portion 14f of the outer sheet 14 forms a standing portion 14s that stands up toward the skin side at a predetermined position outside the absorber 11 in the left-right direction. In FIG. 4, starting from the inner end 51ei in the left-right direction of the first LG joint portion 51 provided on the skin side in the thickness direction and the innermost in the left-right direction among the plurality of LG joint portions 50, the standing portion 14s stands up toward the skin side in the thickness direction.

[0082] Then, as shown in FIG. 4, the standing part 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 standing parts 14s, 14s that are overlapped in the thickness direction, a plurality of leak - proof wall elastic members 19 such as thread rubber are provided in a state of being extended in the longitudinal direction. When the diaper 1 is worn, due to the elasticity exhibited by this leak - proof wall elastic member 19, the tip 14st of the standing part 14s stands up from the standing starting point 51ei to the skin side, and a pair of leak - proof wall parts LSG, LSG are formed.

[0083] (Front body - around part 20) The front body - around part 20 has a body - around sheet 21 and a plurality of body - around elastic members 23, 23, …. The body - around sheet 21 is a sheet member having a rectangular shape in plan view, and as shown in FIG. 3, it is folded back at the upper end 20et in the vertical direction of the front body - around part 20 and joined in a state of being laminated in the thickness direction. As the body - around sheet 21, for example, SMS non - woven fabric (spunbond - meltblown - spunbond non - woven fabric), spunbond non - woven fabric, air - through non - woven fabric, etc. can be applied. Also, between the skin - side and non - skin - side in the thickness direction of the body - around sheet 21 folded back at the upper end 20et, a plurality of body - around elastic members 23, 23, … such as thread rubber are provided at intervals in the vertical direction in a state of being extended at a predetermined elongation ratio in the left - right direction. Due to the elasticity exhibited by the plurality of body - around elastic members 23, the front body - around part 20 is given elasticity along the left - right direction. Also, a part of the plurality of body - around elastic members 23, 23, … has a portion cut at the central part in the left - right direction.

[0084] Also, the front body - around part 20 may have a skin - facing sheet 25. The skin - facing sheet 25 is a sheet member arranged to cover the upper end part 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 bites into the wearer's skin. The skin - facing sheet 25 is formed of a sheet member such as a non - woven fabric equivalent to the body - around sheet 21. However, the skin - facing sheet 25 does not necessarily have to be provided.

[0085] (Rear body circumference part 30) The rear body circumference part 30 has substantially the same configuration as the front body circumference part 20. That is, the rear body circumference part 30 has a body circumference sheet 31 and a plurality of body circumference elastic members 33, 33,.... The body circumference sheet 31 is folded back at the upper end 30et in the vertical direction of the rear body circumference part 30 in substantially the same manner as the body circumference sheet 21, and is joined in a laminated state in the thickness direction. Also, between the skin side and the non-skin side in the thickness direction of the folded body circumference sheet 31, a plurality of body circumference 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 circumference part 30 may have a skin surface sheet 35 substantially the same as the skin surface sheet 25.

[0086] <Regarding the fit of the leg gather part LG> Subsequently, the fit of the leg gather part LG when the diaper 1 is worn will be described. First, as a comparative example, the problems of the leg gather part that occurred in conventional pant-type absorbent articles will be described. FIGS. 5A and 5B are diagrams for explaining the fit of the leg gather part LG at the wearer's crotch (ankle part) when wearing a conventional pant-type diaper.

[0087] Conventionally, in pant-type absorbent articles, in order to improve the fit at the ankle part and suppress lateral leakage of excrement, the length in the left-right direction of the leg gather part LG may be increased (the width may be widened). In that case, it is important to fit the wide leg gather part tightly to the wearer's skin (ankle) 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 part LG and the wearer's skin.

[0088] On the other hand, in the diaper of Fig. 5A, by narrowing the pitch (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 expansion and contraction force of the entire leg gather portion LG is increased. As a result, when wearing the diaper, it is possible to make it difficult to form a gap 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, which may cause discomfort such as the leg gather portion LG digging into the wearer's leg movement. In particular, when the wearer is an infant with sensitive skin, etc., there is a risk that the leg gather portion LG strongly presses against the skin, easily causing swelling and redness in the leg movement.

[0089] 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 the 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 easily deformed like a bellows and wrinkles are likely to occur, deteriorating the fit.

[0090] 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.

[0091] 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 up 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 up 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.

[0092] In the present embodiment, three LG elastic members 17, namely, the inner LG elastic member 17a, the intermediate 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 - 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.

[0093] Furthermore, in the diaper 1, among the plurality of LG elastic members 17 provided in the leg gather portion LG, the LG elastic members 17 are arranged so that the contraction force of the LG elastic members 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 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.

[0094] 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 becomes the second leg gather elastic member. And the LG elastic members 17a to 17c are arranged such that the contraction force of the inner LG elastic member 17a is greater than 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 base 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 follows the movement of the wearer's leg and is likely to fit. Therefore, it is possible to suppress the outer (tip side) LG elastic member 17 from moving to the inner side (base side), and it is possible to suppress the leg gather portion LG from shrinking inward as shown in FIG. 5B.

[0095] 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.

[0096] Note that the LG elastic member 17 itself is not included in the rigidity imparting means. At least, among the LG joint portions 50, the portions that do not overlap with the LG elastic member 17 when viewed in the thickness direction function as the 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 the rigidity imparting means.

[0097] In the diaper 1, the rigidity-imparting means (LG joints 51 to 54) are 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 that 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, making it difficult for the user to be reminded of concerns such as lateral leakage of excrement.

[0098] 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 (which corresponds 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 lateral direction at the position of 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.

[0099] 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 belt - shaped portion indicated by diagonal lines with a width of 5 mm centered on the middle LG elastic member 17b is shown as being cut out as the test piece TP. Similarly, for the inner LG elastic member 17a and the outer LG elastic member 17c, a belt - shaped portion with a width of 5 mm is cut out as the test piece TP. When it is not possible to secure a region with a width of 2.5 mm on only 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 has a width of 2.5 mm only on one side.

[0100] Next, as shown in FIG. 7C, for the test piece TP in the natural state, clamp both longitudinal ends with the chucks of a known tensile testing machine (for example, an Instron universal material testing machine), and adjust the distance Lc between the two 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. 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 measurements 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.

[0101] 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, it is preferable that the contraction force of the LG elastic member 17 arranged on the outer side in the left - right direction is 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, it is preferable that the contraction force of the LG elastic member 17 arranged on the outer side is equal to or less than the contraction force of the LG elastic member 17 arranged on the inner side.

[0102] 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 gathering of the leg gather portion LG is also more easily suppressed. Therefore, while suppressing the surface pressure of the leg gather portion LG from becoming excessively high, the fitness can be further enhanced along the leg - folding shape of the wearer.

[0103] 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, it is preferable that the contraction ratio of the LG elastic member 17 arranged on the outer side is equal to or less than the contraction ratio of the LG elastic member 17 arranged on the inner side.

[0104] With such a configuration, the rate of contraction (contraction rate) of the LG elastic member 17 from the inner side to the outer side 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 folding shape of the wearer while suppressing the surface pressure of the leg gather portion LG from becoming excessively high.

[0105] Also, 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.

[0106] 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.

[0107] 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 arranged 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.

[0108] Then, when the number of LG elastic members 17 arranged in the leg gather elastic region ER (three in diaper 1) equally divides the leg gather elastic region ER in the left - right direction (into three equal parts in 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 intermediate 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.

[0109] 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 will be prone to wrinkling. In contrast, in 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 being chafed or turning red.

[0110] Furthermore, in the leg gather part LG of diaper 1, a rigidity - imparting means is provided in each region where the leg gather elastic region ER is evenly divided (into three equal parts). In FIG. 6, among the leg gather elastic regions ER divided into three equal parts, the second LG joint part 52 and the fourth LG joint part 54 are provided in the inner region ERa in the left - right direction. Similarly, a part of the third LG joint part 53 and the fourth LG joint part 54 are provided in the central region ERb in the left - right direction, and a part of the third LG joint part 53 is provided in the outer region ERc in the left - right direction. 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.

[0111] Also, 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.

[0112] 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 rather than 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 rather than the leak - proof film 13.

[0113] Also, in the diaper 1 of the present embodiment, the contraction force per unit width of the leg gather portion LG is less than or equal to 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 to the maximum along the longitudinal direction (extended state) to 0.7 times the length by the width of the leg gather portion LG (length Wlg in the left - right direction in FIG. 6) is less than or equal to 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 to the maximum along the longitudinal direction (extended state) to 0.7 times the length by the width of the leak - proof wall portion LSG (length Wlsg in the thickness direction in FIG. 6).

[0114] With such a configuration, compared to the reverse case (the contraction force per unit width of the leg gather part LG > the contraction force per unit width of the leakage prevention wall part LSG), the surface pressure of the leg gather part 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 part LG and the leakage prevention wall part LSG can be measured according to the method described with reference to FIG. 7. That is, as test pieces TP, the part of the leg gather part LG shown in FIG. 7A and the part of the leakage prevention wall part 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 it by the length (width) in the left-right direction of the test piece TP, the contraction force per unit width of the leg gather part LG and the leakage prevention wall part LSG can be obtained.

[0115] Also, as described above, the rigidity imparting means for imparting rigidity to the leg gather part LG of the diaper 1 is realized by an adhesive that adheres the sheet members constituting the leg gather part LG in the thickness direction. Specifically, the first LG joint part 51 to the third LG joint part 53 (adhesive) that join the folded-back part 14f of the outer sheet 14 and the leakage prevention film 13 in the thickness direction impart rigidity to the leg gather part LG (see FIG. 6). Similarly, the fourth LG joint part 54 (adhesive) that joins the outer sheet 14 (the non-folded part) and the leakage prevention film 13 in the thickness direction imparts rigidity to the leg gather part LG (see FIG. 6).

[0116] By joining sheet members laminated in the thickness direction to each other with an adhesive, the rigidity of the leg gather portion LG is increased 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 be wrinkled. Also, since an adhesive such as a hot melt adhesive is solidified at room 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 it may be realized by means such as welding described later or providing other sheet members (see FIG. 8).

[0117] Also, 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, and 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 increased 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.

[0118] 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 of the leg gather portion LG (the outer end 10es in the left-right direction), 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 wearer's skin when the diaper 1 is worn, it is difficult to cause discomfort or a sense of discomfort to the wearer.

[0119] 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. As a result, even when the tip edge contacts the wearer's skin when the diaper 1 is worn, it is more difficult to cause discomfort or a sense of discomfort to the wearer.

[0120] 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 leak - proof wall portion LSG in the extended state (the maximum height when the leak - proof 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 leak - proof wall portion LSG is longer than (or may be the same length as) the distance (the standing height of the leak - proof wall portion LSG) Wlsg from the standing start point 51ei of the leak - proof wall portion LSG to the tip 14st of the leak - proof wall portion LSG. With such a configuration, when the diaper 1 is worn, even if the leak - proof wall portion LSG falls outward in the left - right direction from the standing state, it is suppressed that the fallen leak - proof wall portion LSG protrudes outward beyond the tip (outer end 10es) of the leg gather portion LG. Therefore, it is suppressed that a gap is formed by the leak - proof 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.

[0121] Moreover, 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 leak - proof 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 fitness 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.

[0122] <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, similar to FIG. 4. The absorbent body 10 of the modified example is different from the absorbent body 10 described with reference to FIG. 4 in the configuration of the leg gather portion LG and a part of the topsheet 12.

[0123] The absorbent body 10 of the modified example has a welding portion 60 that joins, in the thickness direction, an outer sheet 14 constituting the leg gather portion LG and a folded portion 14f where the outer sheet 14 is folded back at the outer end 10es. The welding portion 60 is constituted by a large number of first welding patterns 61 and second welding patterns 62 being regularly arranged along the longitudinal direction, and each of the welding patterns 61, 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 welding portion 60 is formed to be continuous in the longitudinal direction as a whole. Note that 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 also in the short transverse direction (left - right direction).

[0124] 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 a 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).

[0125] With such a welding portion 60, the joining strength between the sheet members laminated in the thickness direction of the leg gather portion LG is further increased, 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. Note that in FIG. 8, two types of joining portions, the welding portion 60 and the LG joining portion 50, are provided in the leg gather portion LG, but a configuration may be adopted in which the welding portion 60 is formed in place of the LG joining portion 50.

[0126] 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 easily 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.

[0127] 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 wearer's leg in terms of surface.

[0128] <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 around the wearer's waist, 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 cuffs.

[0129] 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 easily causes 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 becomes easy to interfere with the movement of the wearer's leg. In this case, the front torso circumferential part 20 is displaced due to the movement of the wearer's leg, which becomes a factor for significantly deteriorating the fit of the torso circumferential parts 20 and the leg gather part LG.

[0130] 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, the front torso circumferential part 20 will basically be described, and the description of the rear torso circumferential part 30 will be omitted. However, the rear torso circumferential part 30 may be described as necessary.

[0131] 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 divided into four equal parts in the vertical direction, the respective regions are, in order from the upper side, 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, dividing the front torso circumferential part 20 into four equal parts 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 divided into four equal parts in the vertical direction. Similarly, when the rear torso circumferential part 30 is divided into four equal parts in the vertical direction, the respective regions are, in order from the upper side, 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.

[0132] As described above, a plurality of waist elastic members 23, 23... are attached to the front waist 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 of the first front waist region 20A1 to the fourth front waist region 20A4 of the front waist portion 20, by appropriately adjusting the magnitude of the expansion and contraction force (contraction force) exhibited by the waist elastic member 23, better fit can be realized.

[0133] Specifically, in the front waist portion 20 of the diaper 1, the contraction force of the third front waist region 20A3 is made larger than that of the fourth front waist region 20A4. That is, the contraction force when the third front waist 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 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.

[0134] In the diaper 1, by widening (making it 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 legs to become congested or reddened. On the other hand, since the surface pressure of the leg gather portion LG is lowered, there is a possibility that a gap may be generated between the leg gather portion LG and the wearer's skin when the wearer moves their legs during walking or the like. In contrast, by enhancing the fit of the front waist portion 20 and making it difficult for the front waist portion 20 to slip off 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 portion 20 to slip off 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.

[0135] At this time, in the front body circumferential portion 20, by making the contraction force of the third front body circumferential region 20A3 greater than the contraction force of the fourth front body circumferential region 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.

[0136] The abdomen of a person (wearer) usually gradually bulges more toward the front side (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 circumferential region 20A1 and the second front body circumferential region 20A2, and the bulge of the abdomen becomes smaller at the positions of the third front body circumferential region 20A3 and the fourth front body circumferential region 20A4. Also, when the wearer breathes, the abdomen bulges and collapses greatly at the positions of the first front body circumferential region 20A1 and the second front body circumferential region 20A2, whereas the movement of the abdomen is small at the positions of the third front body circumferential region 20A3 and the fourth front body circumferential region 20A4. Therefore, by increasing the contraction forces of the third front body circumferential region 20A3 and the fourth front body circumferential region 20A4 in the front body circumferential portion 20 of the diaper 1, it is difficult to cause discomfort to the wearer due to tightening, and the fit of the front body circumferential portion 20 can be improved.

[0137] However, since the lower end of the fourth front torso region 20A4 constitutes a part of the leg opening LH of the diaper 1 (see FIG. 1), if the contraction force of the fourth front torso 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 torso region 20A4 smaller than the contraction force of the third front torso region 20A3, the lower end of the fourth front torso region 20A4 (leg opening LH) is less likely to interfere with the movement of the wearer's legs. As a result, the front torso portion 20 can easily fit around the wearer's abdomen without interfering with the movement of the wearer's body (such as leg movement and abdominal movement due to breathing). And, by enhancing the fit of the front torso 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.

[0138] Here, the contraction forces of the respective regions 20A1 to 20A4 of the front torso portion 20 can be measured as follows according to the method described in FIG. 7. First, the absorbent body 10 is peeled off from the front torso 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 torso elastic member 23 is disposed on the boundary of the regions 20A1 to 20A4, the torso elastic member 23 is included in the upper (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 becomes 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 length of the test piece TP is contracted until it 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).

[0139] 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 a 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 a portion with small abdominal movement (fluctuation) and fixing the position, the entire front body circumferential portion 20 is less likely to shift downwards, and the fitting properties of the front body circumferential portion 20 and the leg gather portion LG can be further enhanced.

[0140] 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 properties can be efficiently enhanced.

[0141] In particular, infants and young children assumed as the wearing target of the diaper 1 generally have a body type in which the abdomen is likely to be pot-bellied, 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 properties for infants and young children with pot-bellied bellies while ensuring safety during wearing.

[0142] In the front body circumferential portion 20 of the diaper 1, the contraction force is adjusted so as to decrease in the order of the third front body circumferential region 20A3, the fourth front body circumferential region 20A4, the first front body circumferential region 20A1, and the second front body circumferential region 20A2. This makes it easier to achieve the good fit as described above.

[0143] Also, when focusing on the rear body circumferential portion 30, in the diaper 1, among the first rear body circumferential region 30A1 to the fourth rear body circumferential region 30A4, the contraction force of the third rear body circumferential region 30A3 is the largest. That is, also in the rear body circumferential portion 30, similar to the front body circumferential 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, when the third front body circumferential region 20A3 and the third rear body circumferential region 30A3 that are annularly connected are interlocked, 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 circumferential portions 20 and 30 in the said region (20A3, 30A3), it becomes difficult for the entire body circumferential portions 20 and 30 to be displaced, and the fit can be further improved without causing discomfort to the wearer.

[0144] On the other hand, in the rear body circumferential portion 30, the contraction force of the second rear body circumferential region 30A2 may be made the largest. In the back of the wearer, the region where the second rear body circumferential region 30A2 hits is, as shown in FIG. 10, a 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 circumferential portion 30 on the back. As a result, the front body circumferential portion 20 and the rear body circumferential portion 30 are easily firmly fixed to the wearer's body circumference on both the front and back sides, slippage of the body circumferential portions 20 and 30 is suppressed, and the fit is improved.

[0145] 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 the 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 fold starting 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.

[0146] 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.

[0147] 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 it becomes difficult for the heavy absorbent main body 10 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.

[0148] 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, the third front body circumferential region 20A3 and the absorber 11 have a non-overlapping portion. In the non-overlapping portion, since the contraction force of the third front body circumferential region 20A3 is difficult to be inhibited by the highly rigid absorber 11, a large contraction force can be applied to the recess of 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.

[0149] Further, the average pitch in the vertical direction of the waist elastic members 23, 23... disposed in the third front waist region 20A3 is preferably 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 is likely 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.

[0150] Also, 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.

[0151] 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 (ventral side) or the rear (dorsal side), the above-described effects can be obtained.

[0152] ===Other Embodiments=== As described above, the embodiments of the present invention have been explained. 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.

[0153] In the above-described embodiment, the circumferential elastic member 23(33) such as a 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 of the front circumferential portion 20 (near the first front circumferential region 20A1 in FIG. 9), thereby imparting elasticity.

[0154] 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 prevention 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 an LG elastic member in an extended state between the separate sheet member (LG non-woven fabric) and the outer sheet 14 in the thickness direction. Further, a part of the LG non-woven fabric may be provided so as to cover the left-right outer end portion of the outer sheet 14 from the non-skin side, and an 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

[0155] 1 Diaper (pant-type absorbent article), 2 Side joining 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 Leakage prevention film, 14 Outer packaging sheet, 14f Folding part, 14s Standing part, 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 Leakage prevention wall elastic member, 20 Front body circumference part, 20A1 First front body circumference area, 20A2 Second front body circumference area, 20A3 Third front body circumference area, 20A4 Fourth front body circumference area, 21 Body circumference sheet, 23 Body circumference elastic member, 25 Skin side sheet, 30 Rear body circumference part, 30A1 First rear body circumference area, 30A2 Second rear body circumference area, 30A3 Third rear body circumference area, 30A4 Fourth rear body circumference area, 31 Body circumference sheet, 33 Body circumference elastic member, 35 Skin side sheet, 50 LG joint part (leg gather joint part), 51 First LG joint part, 51ei Inner end (standing start point), 52 Second LG joint part, 53 Third LG joint part, 54 Fourth LG joint part, 60 Welding part, 60ei Standing start point, 61 First welding pattern, 62 Second welding pattern, 70 Body joint part, BH Body circumference opening, LH Leg circumference opening, LG Leg gather part, LSG Leakage prevention wall part, 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 torso portion, and a rear torso portion, the front torso portion and the rear torso portion are joined to each other by a pair of side joining portions at both ends 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, a pant-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, when the first leg gather elastic member is stretched to 0.9 times its length when stretched most along the longitudinal direction and then returned 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 stretched to 0.9 times its length when stretched most along the longitudinal direction and then returned to 0.7 times its length, the front torso portion and the rear torso portion have elasticity along the horizontal direction, when the front torso 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 top is the third front torso region and the fourth region from the top is the fourth front torso region, when the third front torso region is stretched to 0.9 times its length when stretched most along the horizontal direction and then returned to 0.7 times its length, the contraction force of the third front torso region, is greater than the contraction force of the fourth front torso region when the fourth front torso region is stretched to 0.9 times its length when stretched most along the horizontal direction and then returned to 0.7 times its length, a pant-type absorbent article characterized by this.

2. The pant-type absorbent article according to Claim 1, among the two leg gather elastic members arranged adjacent to each other in the horizontal direction, when the leg gather elastic member arranged inside in the horizontal direction is stretched to 0.9 times its length when stretched most along the longitudinal direction and then returned to 0.7 times its length, the contraction force, The pants-type absorbent article is characterized in that the leg gather elastic member disposed on the outer side in the left-right direction has a contraction force equal to or greater than the contraction force when the leg gather elastic member is extended to 0.9 times the length when it is extended to the maximum along the longitudinal direction and then returned to 0.7 times the length.

3. The pants-type absorbent article according to claim 1 or 2, Among the two leg gather elastic members arranged adjacent to each other in the left-right direction, For the leg gather elastic member disposed on the inner side in the left-right direction, the value obtained by dividing the length in the natural state by the length when extended to the maximum along the longitudinal direction is For the leg gather elastic member disposed on the outer side in the left-right direction, the value obtained by dividing the length in the natural state by the length when extended to the maximum along the longitudinal direction is less than or equal to the above value. The pants-type absorbent article is characterized by this.

4. The pants-type absorbent article according to claim 1 or 2, Among 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 disposed on the inner side in the left-right direction in the natural state is The pants-type absorbent article is characterized in that it is equal to or greater than the cross-sectional area of the leg gather elastic member disposed on the outer side in the left-right direction in the natural state.

5. The pants-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 portion in the extended state to the starting point of the standing of the leakage-preventing wall portion is The pants-type absorbent article is characterized in that it is equal to or greater than the shortest distance from the starting point of the standing of the leakage-preventing wall portion to the tip of the leakage-preventing wall portion in the extended state.

6. The pants-type absorbent article according to claim 1 or 2, 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 joint portion, and the first region from the upper side is the first front body circumference region and the second region from the upper side is the second front body circumference region, For each of the first front body circumference region to the fourth front body circumference region, the magnitude of the contraction force when extended to 0.9 times the length when extended to the maximum along the left-right direction and then returned to 0.7 times the length is The pants-type absorbent article is characterized in that the third front body circumference region is the largest.

7. The pants-type absorbent article according to claim 6, The sum of the contraction forces of the third front body circumference region and the fourth front body circumference region is A pants-type absorbent article, characterized in that the total contraction force of the first front hip circumference region and the second front hip circumference region is greater. **Claim 8** The pants-type absorbent article according to claim 6, when the rear hip circumference 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 the first rear hip circumference region, the second region from the upper side is the second rear hip circumference region, the third region from the upper side is the third rear hip circumference region, and the fourth region from the upper side is the fourth rear hip circumference region, for each of the first rear hip circumference region to the fourth rear hip circumference region, the magnitude of the contraction force 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, is characterized in that the third rear hip circumference region is the largest. **Claim 9** The pants-type absorbent article according to claim 6, when the rear hip circumference 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 the first rear hip circumference region, the second region from the upper side is the second rear hip circumference region, the third region from the upper side is the third rear hip circumference region, and the fourth region from the upper side is the fourth rear hip circumference region, for each of the first rear hip circumference region to the fourth rear hip circumference region, the magnitude of the contraction force 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, is characterized in that the second rear hip circumference region is the largest. **Claim 10** The pants-type absorbent article according to claim 1 or 2, characterized in that in the natural state, the length of the third front hip circumference region in the left-right direction is shorter than the length of the fourth front hip circumference region in the left-right direction. **Claim 11** The pants-type absorbent article according to claim 10, when the front hip circumference part is divided into two 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 the first front hip circumference region and the second region from the upper side is the second front hip circumference region, in the natural state, the average length of the third front hip circumference region and the fourth front hip circumference region in the left-right direction, is characterized in that in the natural state, it is shorter than the average length of the first front hip circumference region and the second front hip circumference region in the left-right direction.

12. The pant-type absorbent article according to claim 1 or 2, wherein it has a main body joining part that joins the absorbent main body and the front body circumferential part, in the vertical direction, the upper end of the main body joining part is located above the upper end of the third front body circumferential region, A pant-type absorbent article characterized by this.

13. The pant-type absorbent article according to claim 12, wherein the absorbent main body has a liquid-absorbent absorber, in the vertical direction, the upper end of the absorber is located below the upper end of the third front body circumferential region, A pant-type absorbent article characterized by this.

14. The pant-type absorbent article according to claim 1 or 2, wherein the front body circumferential part has a plurality of body circumferential elastic members that expand and contract in the left-right direction, spaced apart in the vertical direction, the average pitch in the left-right direction of the leg gather elastic member disposed in the leg gather part is larger than the average pitch in the vertical direction of the body circumferential elastic member disposed in the third front body circumferential region, A pant-type absorbent article characterized by this.

15. The pant-type absorbent article according to claim 1 or 2, wherein in the region of the leg gather part from the outermost end in the left-right direction to the leg gather elastic member disposed most inwardly, it has rigidity imparting means for imparting rigidity to the leg gather part, 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 part, A pant-type absorbent article characterized by this.

16. The pant-type absorbent article according to claim 15, wherein the leg gather part has at least two sheet members laminated in the thickness direction, and the leg gather elastic member is provided between the laminated sheet members, the rigidity imparting means imparts rigidity to the leg gather part by joining the laminated sheet members to each other, A pant-type absorbent article characterized by this.

17. The pant-type absorbent article according to claim 1 or 2, wherein the front body circumferential part and the rear body circumferential part have body circumferential elastic members that expand and contract in the left-right direction, The pant-type absorbent article is characterized in that, when viewed in the thickness direction, at least one of the front body circumferential portion and the rear body circumferential portion has a portion where the body circumferential elastic member and the leg gather elastic member intersect.

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