Elastic sheet and underpants-type absorbent article

Abstract

In an elastic sheet (40) in which a plurality of elastic members (23) are disposed between a pair of sheets (21, 22) joined by a plurality of joining sections (50), the elastic sheet has joining section groups (50G) that include at least one pair of joining sections (50) that sandwich the elastic members (23), and when the space between vertically adjacent joining section groups (50G) in a state in which the elastic sheet is elongated in the left-right direction is defined as a non-placement region (Np), the elastic members (23) are disposed in the non-placement region (Np). The first, second, and third joining part rows (R1, R2, R3) are adjacent in the left-right direction, the joining parts (50) in the first, second, and third joining part rows overlap each other at one position (P1) in the vertical direction, and the non-arrangement regions (Np) in the first, second, and third joining part rows overlap each other at the other position (P2).

Description

Technical Field

[0001] The present invention relates to a stretchable sheet and a panty-type absorbent article. Background Art

[0002] Conventionally, as a sheet used for absorbent articles such as disposable diapers, a stretchable sheet in which elastic members such as rubber threads are joined in an extended state between two sheets is known. For example, Patent Document 1 discloses a stretchable sheet in which an elastic member is sandwiched between two sheets made of fiber sheets, and the two sheets are joined by a plurality of melting portions formed on both sides of the elastic member at intervals along the extending direction of the elastic member.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2020-199246 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] In the case where a plurality of melting portions are intermittently provided along the extending direction of the elastic member as in Patent Document 1, beautiful wrinkles can be formed in the direction orthogonal to the extending direction of the elastic member (article length direction), improving the skin feel and aesthetics. However, on the other hand, corresponding to the beautiful formation of wrinkles, the frictional force sometimes becomes high due to the standing of the wrinkles. In addition, such wrinkles are difficult to be compressed, and there is a possibility of discomfort during wearing. In the stretchable sheet of Patent Document 1, a portion of the region where one of the two sheets overlaps the elastic member in the thickness direction has a region where the void ratio between the constituent fibers is relatively high, thereby reducing the degree to which the elastic member presses on the wearer's skin. However, improvement in softness is also sought in addition to the region overlapping the elastic member in the thickness direction.

[0008] The present invention has been made in view of the above problems, and an object thereof is to provide a stretchable sheet that beautifully forms wrinkles along the up-and-down direction of the stretchable sheet and improves softness to reduce discomfort during use.

[0009] Means for Solving the Problems

[0010] The main invention for achieving the above object is a stretchable sheet having an up-down direction and a left-right direction that cross each other. Between a pair of sheets joined by a plurality of joining portions, a plurality of elastic members capable of stretching in the left-right direction are arranged at intervals in the up-down direction. It is characterized in that the stretchable sheet has a group of joining portions including at least a pair of the joining portions that sandwich the elastic members. The plurality of groups of joining portions constitute a first joining portion row, a second joining portion row, and a third joining portion row along the up-down direction. In a state of being stretched in the left-right direction, the length in the up-down direction between the joining portions adjacent in the up-down direction in the group of joining portions is smaller than the length in the left-right direction of the joining portion. When a region between the groups of joining portions adjacent in the up-down direction is set as a non-arrangement region where the group of joining portions is not arranged, the length in the up-down direction of the non-arrangement region is larger than the length in the up-down direction between the pair of joining portions. The first joining portion row, the second joining portion row, and the third joining portion row are adjacent in the left-right direction. At one position in the up-down direction, the joining portions in the first joining portion row, the joining portions in the second joining portion row, and the joining portions in the third joining portion row overlap. At another position in the up-down direction, the non-arrangement regions in the first joining portion row, the non-arrangement regions in the second joining portion row, and the non-arrangement regions in the third joining portion row overlap.

[0011] Other features of the present invention will become clear from the description of this specification and the drawings.

[0012] Effects of the Invention

[0013] According to the present invention, a stretchable sheet can be provided, which beautifully forms wrinkles along the up-down direction of the stretchable sheet and improves softness to reduce discomfort during use. Description of the Drawings

[0014] Figure 1 is a schematic perspective view of the panty-type disposable diaper 1.

[0015] Figure 2 is a schematic plan view of the unfolded and stretched diaper 1 viewed from the skin side of the wearer.

[0016] Figure 3 is Figure 2 a schematic cross-sectional view taken along line A-A in

[0017] Figure 4 is an explanatory view of the joining portion row R provided at the ventral waist portion 20.

[0018] Figure 5A and Figure 5BIt is an explanatory diagram of the installation function of the waist circumference elastic member 23.

[0019] Figure 6 It is a diagram that magnifies a part of the joint row R.

[0020] Figure 7 It is a magnification of Figure 6 a part of the joint row R therein.

[0021] Figure 8 It is an explanation of Figure 4 the joint row R of the upper end portion 20A shown.

[0022] Figure 9 It is a diagram for explaining between adjacent joint groups 50G in the left - right direction.

[0023] Figure 10 It is a diagram showing a modification of the arrangement of the joint row R.

[0024] Figure 11 It is a diagram showing a modification of the joint row R.

[0025] Figure 12 It is a diagram showing another modification of the joint row R.

[0026] Figure 13 It is a diagram for explaining the adhesive portion 70 of the folded - back portion 22r. Detailed implementation mode

[0027] At least the following matters will be clear from the description of this specification and the accompanying drawings.

[0028] Pattern 1 is a stretchable sheet. The stretchable sheet has a vertical direction and a horizontal direction that intersect with each other. Between a pair of sheets joined by a plurality of joining portions, a plurality of elastic members capable of stretching in the horizontal direction are arranged at intervals in the vertical direction. It is characterized in that the stretchable sheet has a group of joining portions, and the group of joining portions includes at least a pair of the joining portions that sandwich the elastic member. A plurality of the groups of joining portions constitute a first joining portion row, a second joining portion row, and a third joining portion row along the vertical direction. In a state of being stretched in the horizontal direction, the length in the vertical direction between the joining portions adjacent in the vertical direction in the group of joining portions is smaller than the length in the horizontal direction of the joining portion. When a region between the groups of joining portions adjacent in the vertical direction is set as a non-arrangement region where the group of joining portions is not arranged, the length in the vertical direction of the non-arrangement region is greater than the length in the vertical direction between the pair of the joining portions. The first joining portion row, the second joining portion row, and the third joining portion row are adjacent in the horizontal direction. At one position in the vertical direction, the joining portions in the first joining portion row, the joining portions in the second joining portion row, and the joining portions in the third joining portion row overlap. At another position in the vertical direction, the non-arrangement regions in the first joining portion row, the non-arrangement regions in the second joining portion row, and the non-arrangement regions in the third joining portion row overlap.

[0029] According to the stretchable sheet like Pattern 1, the joining portions in the first joining portion row, the second joining portion row, and the third joining portion row adjacent in the horizontal direction are formed at a common position in the vertical direction. Thus, it is easy to form beautiful wrinkles along the vertical direction. In addition, the non-arrangement region where the group of joining portions is not arranged is a region that is easily compressed. The non-arrangement region is also set at a common position in the vertical direction in the first joining portion row, the second joining portion row, and the third joining portion row adjacent in the horizontal direction. Thus, a space along the horizontal direction is formed and is easily compressed. As a result, the flexibility of the stretchable sheet is improved, and the possibility of discomfort during wearing can be reduced.

[0030] Pattern 2 is the stretchable sheet as described in Pattern 1, and is characterized in that in a state of being stretched in the horizontal direction, the length in the vertical direction of the group of joining portions is greater than the length in the horizontal direction.

[0031] According to the stretchable sheet like Pattern 2, the group of joining portions is longer in the vertical direction. Thus, it is easier to form wrinkles along the vertical direction.

[0032] Style 3 is a stretchable sheet as described in Style 1 or 2, characterized in that, in a state of being stretched in the above-mentioned left-right direction, among two of the non-arrangement regions in the first joint portion row that overlap at the above-mentioned other position, the non-arrangement region in the second joint portion row, and the non-arrangement region in the third joint portion row, when the region that overlaps in the above-mentioned up-down direction is set as the overlapping region and the region that does not overlap in the above-mentioned up-down direction is set as the non-overlapping region, the length of the overlapping region in the above-mentioned up-down direction is greater than the length of the non-overlapping region in the above-mentioned up-down direction.

[0033] According to the stretchable sheet like Style 3, this overlapping region is a region where it is easy to form a space along the left-right direction, and the length of the overlapping region in the up-down direction is long. Thus, it is easier to ensure a larger space and the flexibility can be improved.

[0034] Style 4 is a stretchable sheet as described in any one of Styles 1 to 3, characterized in that, in a state of being stretched in the above-mentioned left-right direction, the length of the non-arrangement region in the above-mentioned up-down direction is greater than the length of the joint portion group in the above-mentioned up-down direction.

[0035] According to the stretchable sheet like Style 4, the non-arrangement region where the joint portion group is not arranged is long. Thus, a larger region that can be easily compressed can be ensured.

[0036] Style 5 is a stretchable sheet as described in Style 4, characterized in that the length of the non-arrangement region in the above-mentioned up-down direction is 3 times or less the length of the joint portion group in the above-mentioned up-down direction.

[0037] According to the stretchable sheet like Style 5, if the non-arrangement region where the joint portion group is not arranged is too long, it is difficult to form wrinkles along the up-down direction. By setting the length of the non-arrangement region in the up-down direction to 3 times or less the length of the joint portion group in the up-down direction, it is possible to prevent the joint portion groups from being overly separated from each other in the up-down direction, and it promotes the formation of wrinkles along the up-down direction relying on the joint portion group.

[0038] Style 6 is a stretchable sheet as described in any one of Styles 1 to 3, characterized in that, in a state of being stretched in the above-mentioned left-right direction, the length of the non-arrangement region in the above-mentioned up-down direction is less than the length of the joint portion group in the above-mentioned up-down direction.

[0039] According to the stretchable sheet like Style 6, the length of the joint portion group in the up-down direction is greater than the length of the non-arrangement region in the up-down direction. Thus, it is easier to form wrinkles along the up-down direction.

[0040] Pattern 7 is a stretchable sheet as described in any one of Patterns 1 to 6, characterized in that, in a state of being elongated in the left-right direction, when a region between the adjacent groups of joints in the left-right direction is set as an inter-column non-arrangement region where the groups of joints are not arranged, the length of the inter-column non-arrangement region in the left-right direction is greater than the length of the groups of joints in the up-down direction.

[0041] Regarding the stretchable sheet like Pattern 7, in the case of a configuration where the length of the inter-column non-arrangement region in the left-right direction is short, wrinkles along the up-down direction are likely to be formed thinly, and as a result, there is a possibility that the skin feel becomes hard. By setting the length of the inter-column non-arrangement region in the left-right direction to be greater than the length of the groups of joints in the up-down direction, large wrinkles along the up-down direction are easily formed, and the flexibility can be improved.

[0042] Pattern 8 is a stretchable sheet as described in Pattern 7, characterized in that the length of the inter-column non-arrangement region in the left-right direction is 3 times or less the length of the groups of joints in the up-down direction.

[0043] Regarding the stretchable sheet like Pattern 8, if the length of the inter-column non-arrangement region where the groups of joints are not arranged in the left-right direction is too long, it is difficult to form wrinkles along the up-down direction. Therefore, by setting the length of the inter-column non-arrangement region in the left-right direction to be 3 times or less the length of the groups of joints in the up-down direction, excessive separation between the groups of joints in the left-right direction can be prevented, and the formation of wrinkles along the up-down direction relying on the groups of joints is promoted.

[0044] Pattern 9 is a stretchable sheet as described in any one of Patterns 1 to 8, characterized in that an auxiliary joint for joining the pair of sheets, which is different from the joint, is provided in a part of the non-arrangement region.

[0045] Regarding the stretchable sheet like Pattern 9, if the interval between the adjacent groups of joints in the up-down direction (the so-called length of the non-arrangement region in the up-down direction) becomes long, it is difficult to form regular wrinkles along the up-down direction. By providing an auxiliary joint in a part of the non-arrangement region, regular wrinkles along the up-down direction are easily formed.

[0046] Pattern 10 is a stretchable sheet as described in any one of Patterns 1 to 9, characterized in that, in a state where the elastic member is contracted, protrusions protruding toward one side or the other side in the thickness direction of the stretchable sheet are formed in the non-arrangement regions in the first joint column, the non-arrangement regions in the second joint column, and the non-arrangement regions in the third joint column that overlap at another position in the up-down direction.

[0047] According to the stretchable sheet like Pattern 10, since no joint portions are arranged in each non-arrangement area, it is an area that is easily compressed. When the elastic member contracts, the folds along the vertical direction formed on both outer sides in the left-right direction of the joint portion group also extend to both outer sides in the left-right direction of the non-arrangement area, and in the non-arrangement area that is easily compressed without joint portions, a protrusion protruding toward one side or the other side in the thickness direction is formed by contraction. By forming a plurality of protrusions with good skin touch, the flexibility of the stretchable sheet is improved.

[0048] Pattern 11 is the stretchable sheet according to any one of Patterns 1 to 10, characterized in that when the joint portions arranged at both ends in the vertical direction among the above joint portion group are respectively set as an upper end joint portion and a lower end joint portion, the lengths in the vertical direction of the upper end joint portion and the lower end joint portion are greater than the lengths in the vertical direction of the joint portions other than the upper end joint portion and the lower end joint portion among the joint portion group.

[0049] According to the stretchable sheet like Pattern 11, an elastic member is arranged between any pair of joint portions in the joint portion group. However, at this time, in the manufacturing process, when an elastic member is to be arranged between a pair of joint portions including the upper end joint portion or the lower end joint portion, there is a possibility that it will be arranged at a displaced position. By setting the lengths in the vertical direction of the upper end joint portion and the lower end joint portion located at both ends among the joint portion group to be long, the elastically deformed member that is excessively displaced can be cut off by the upper end joint portion or the lower end joint portion, and the arrangement of the elastic member at an unexpected position can be avoided.

[0050] Style 12 is a panty-type absorbent article having the stretchable sheet described in any one of Styles 1 to 11. The panty-type absorbent article has an up-down direction, a left-right direction, and a front-back direction that intersect each other. The panty-type absorbent article has an absorbent main body and a pair of waist regions. The stretchable sheet is provided in at least one of the pair of waist regions. The up-down direction of the stretchable sheet is along the up-down direction of the panty-type absorbent article, the left-right direction of the stretchable sheet is along the left-right direction of the panty-type absorbent article, and the thickness direction of the stretchable sheet is along the front-back direction of the panty-type absorbent article. The pair of waist regions are joined at both side portions in the left-right direction by a pair of side joining portions. At least one of the pair of waist regions has a laminated portion in which the pair of sheets and a sheet different from the pair of sheets are bonded by an adhesive portion in a manner overlapping in the front-back direction, or a folded-back portion in which at least one of the pair of sheets is folded back toward the inner surface side of the waist region and bonded by an adhesive portion. The panty-type absorbent article has a portion where a non-bonded portion other than the adhesive portion in the laminated portion or a non-bonded portion other than the adhesive portion in the folded-back portion overlaps with the non-arrangement region in a top view.

[0051] In the panty-type absorbent article like Style 12, the portion where the non-bonded portion in the laminated portion or the non-bonded portion in the folded-back portion overlaps with the non-arrangement region is a region where the number of layers of the material laminated in the thickness direction increases and there is no adhesive portion for bonding the material. This overlapping portion is a portion that is more easily compressible. By providing such an easily compressible portion, the skin feel is improved.

[0052] ===Embodiment===

[0053] In the present embodiment, as a panty-type absorbent article using a stretchable sheet, an adult-use panty-type disposable diaper is taken as an example to illustrate the embodiment.

[0054] <<Basic Configuration of Panty-Type Disposable Diaper 1>>

[0055] Figure 1 is a schematic perspective view of a panty-type disposable diaper 1 (hereinafter also referred to as "diaper").

[0056] Figure 2 is a schematic top view of the diaper 1 in an unfolded and stretched state as viewed from the skin side of the wearer. Figure 3 is Figure 2 a schematic cross-sectional view taken along line A - A in

[0057] The "unfolded state" of the diaper 1 refers to the following state: By Figure 1When the side joint portions SS (described later) provided on both sides of the diaper 1 in the left - right direction in the pant - type state are disengaged, the ventral waist portion 20 (described later) and the dorsal waist portion 30 (described later) are separated, and the diaper 1 is unfolded on a plane by opening it in the up - down direction. In addition, the "elongated state" of the diaper 1 means that the product (diaper 1) is elongated into a state without wrinkles. Specifically, it refers to the following state: it is elongated until the dimensions of each component (such as the absorbent main body 10, the ventral waist portion 20, etc.) constituting the diaper 1 become the same as or similar to the dimensions of the component alone.

[0058] The diaper 1 is in Figure 1 the pant - type state during use as shown, having mutually intersecting up - down, left - right, and front - back directions, a waist opening BH, and a pair of leg openings LH. In the up - down direction, the waist - opening BH side is set as the upper side, and the side corresponding to the crotch side of the wearer is set as the lower side. In the front - back direction, the side corresponding to the ventral side of the wearer is set as the front side, and the side corresponding to the dorsal side is set as the back side. In addition, in Figure 2 the unfolded and elongated state shown, the diaper 1 has a length direction, a left - right direction, and a thickness direction as three mutually orthogonal directions ( Figure 2 the direction passing through the paper surface in the figure). Moreover, the length direction is along the aforementioned up - down direction. And one side of the length direction corresponds to the ventral side (front side), and the other side corresponds to the dorsal side (back side). In addition, the diaper 1 has a thickness direction in which material layers are laminated as shown in Figure 3 the figure. In the thickness direction, the side in contact with the wearer is set as the skin - side, and the opposite side is set as the non - skin - side.

[0059] The diaper 1 has an absorbent main body 10 and an outer package 18. The outer package 18 has a pair of waist portions 20, 30 and a crotch portion 35 located at the crotch of the wearer. The outer package 18 is joined to the non - skin side surface of the absorbent main body 10 using an adhesive or the like. Among the pair of waist portions 20, 30, the waist portion located at the front side is also called the ventral waist portion 20, and the waist portion located at the rear side is also called the dorsal waist portion 30. The ventral waist portion 20 and the dorsal waist portion 30 are joined by a pair of side joint portions SS on both side portions in the left - right direction. Examples of the joining method relying on the side joint portion SS include thermal melting, ultrasonic welding, and the joining method relying on an adhesive.

[0060] As shown in Figure 3As shown, the absorbent body 10 has: an absorbent core 11; a liquid-permeable topsheet 12 disposed on the skin side with respect to the absorbent core 11; a liquid-impermeable backsheet 13 disposed on the non-skin side with respect to the absorbent core 11; and an outer wrapper 14. The absorbent core 11 may be configured to absorb and hold excreted liquid, and examples thereof include a configuration in which a liquid-absorbing material such as pulp fibers or superabsorbent polymers is formed into a predetermined shape. Additionally, the absorbent core 11 may be covered with a liquid-permeable sheet such as tissue paper or non-woven fabric.

[0061] As Figure 2 shown, leg elastic members 15 (such as rubber threads) that stretch along the length direction of the absorbent body 10 may be provided on both side portions of the absorbent body 10 in the left-right direction. Furthermore, for example, an elastic member that stretches along the length direction may be provided at a position inside the leg elastic members 15 in the left-right direction to form a leak-proof wall portion that can stand up toward the skin side.

[0062] As Figure 2 and Figure 3 shown, the outer wrapper 18 has an outer topsheet 21, a ventral outer backsheet 22, and a dorsal outer backsheet 32.

[0063] The outer topsheet 21 extends from the ventral waist portion 20 through the crotch portion 35 to the dorsal waist portion 30 ( Figure 3 ). The width (length in the left-right direction) of the outer topsheet 21 in the ventral waist portion 20 and the dorsal waist portion 30 is greater than the width (length in the left-right direction) of the outer topsheet 21 in the crotch portion 35 ( Figure 2 ). The outer topsheet 21 may be formed of thermally bonded non-woven fabric, spunbond non-woven fabric, SMS non-woven fabric (spunbond - meltblown - spunbond non-woven fabric), waterproof film, etc.

[0064] As Figure 2 and Figure 3 shown, the ventral outer backsheet 22 is disposed on the non-skin side with respect to the outer topsheet 21, and the ventral waist portion 20 is formed by the ventral outer backsheet 22 and the outer topsheet 21. The outer end (upper end) of the ventral outer backsheet 22 in the length direction is folded back toward the skin side. The folded portion 22r of the ventral outer backsheet 22 encloses one end (outer end) of the outer topsheet 21 in the length direction.

[0065] Moreover, the outer end (upper end) of the ventral outer backsheet 22 in the length direction may also be configured not to be folded back.

[0066] Similarly, as Figure 2 and Figure 3As shown, the dorsal outer mounting base film 32 is disposed on the non-skin side as compared with the outer mounting top film 21, and the dorsal waist portion 30 is constituted by the dorsal outer mounting base film 32 and the outer mounting top film 21. The outer end (upper end) of the dorsal outer mounting base film 32 in the longitudinal direction is folded back toward the skin side. The folded-back portion 32r of the dorsal outer mounting base film 32 encloses the other end (outer end) of the outer mounting top film 21 in the longitudinal direction. Moreover, the outer end (upper end) of the dorsal outer mounting base film 32 in the longitudinal direction may also be configured not to be folded back.

[0067] The ventral outer mounting base film 22 and the dorsal outer mounting base film 32 can be formed of a hot air non-woven fabric, a spunbond non-woven fabric, an SMS non-woven fabric (spunbond / meltblown / spunbond non-woven fabric), or the like.

[0068] The ventral waist portion 20 and the dorsal waist portion 30 respectively include waist elastic members 23, 33 (such as rubber threads) that can stretch in the left-right direction. A plurality of waist elastic members 23, 33 are arranged at intervals in the up-down direction between the outer mounting top film 21 and the ventral outer mounting base film 22 and between the outer mounting top film 21 and the dorsal outer mounting base film 32 (see Figure 2 and Figure 3 ).

[0069] In addition, in the present embodiment, in the dorsal waist portion 30, a hind-leg circumference elastic member 34 is provided between the outer mounting top film 21 and the dorsal outer mounting base film 32. The hind-leg circumference elastic member 34 may also be, for example, a plurality of rubber threads or a stretchable belt-like elastic sheet. The hind-leg circumference elastic member 34 is joined and fixed in an extended state using an adhesive such as a hot melt adhesive.

[0070] As described above, the basic configuration of the diaper 1 has been described, but the configuration of the diaper 1 described above is an example and is not limited thereto. For example, in the diaper 1 of the present embodiment, the outer package 18 has a configuration including the ventral waist portion 20, the dorsal waist portion 30, and the crotch portion 35 that connects them, but is not limited thereto. For example, it may also be a diaper having a configuration in which the ventral waist portion 20 and the dorsal waist portion 30 are formed of separate members and the non-skin side of the absorbent main body 10 is exposed in the crotch portion, or a diaper having an outer package member formed of a single member that is continuous from the ventral waist portion 20 to the dorsal waist portion 30.

[0071] <<Regarding the waist portions 20, 30 (stretchable sheet 40)>>

[0072] Figure 4 It is an explanatory diagram of the joint portion row R provided in the ventral waist portion 20. Figure 5A and Figure 5B It is an explanatory diagram of the mounting function of the waist elastic member 23. Figure 6 It is a diagram showing an enlarged part of the joint portion row R.

[0073] InFigure 4 , Figure 6 In the attached drawings of Figure 6 , the state of the ventral waist portion 20 (elastic sheet 40) when elongated in the left - right direction is shown. The state where the waist portions 20, 30 or the elastic sheet 40 are elongated in the left - right direction is a state where they are elongated to such an extent that the wrinkles generated on the waist portions 20, 30 or the elastic sheet 40 are substantially invisible. It is the following state: elongated until the dimensions of each member (such as the outer top sheet 21, etc.) constituting the waist portions 20, 30 or the elastic sheet 40 become the same as or close to the dimensions of the member alone (i.e., the dimensions when the elasticity of the elastic member is not manifested).

[0074] <Regarding the position limitation of the waist elastic members 23>

[0075] The ventral waist portion 20 and the dorsal waist portion 30 are constituted by an elastic sheet 40, and a plurality of waist elastic members 23, 33 (elastic members) capable of stretching in the left - right direction are arranged at intervals in the up - down direction between the outer top sheet 21 and the ventral outer bottom sheet 22 or between the outer top sheet 21 and the dorsal outer bottom sheet 32 (between a pair of sheets) joined by a plurality of joining portions 50. As Figure 4 and Figure 6 shown, the outer top sheet 21 and the ventral outer bottom sheet 22 (dorsal outer bottom sheet 32) are intermittently joined by a plurality of joining portions 50 dispersed in the up - down direction and the left - right direction. The joining portion 50 can be formed by well - known welding methods such as ultrasonic welding or thermal melting, for example.

[0076] The pair of sheets joined by the joining portion 50 can be either two separate sheets like the outer top sheet 21 and the ventral outer bottom sheet 22 (dorsal outer bottom sheet 32) in the present embodiment, or a single sheet folded back into two layers. In addition, the joining portion 50 is not limited to joining only the pair of sheets sandwiching the waist elastic members 23, 33, and can also join three or more sheets together with the sheets laminated on the pair of sheets.

[0077] Since the ventral waist portion 20 and the dorsal waist portion 30 have substantially the same configuration, hereinafter, the ventral waist portion 20 will be described on behalf of both.

[0078] In the present embodiment, the ventral waist portion 20 (elastic sheet 40) has a plurality of joining portion rows R in which a plurality of joining portions 50 are arranged in the up - down direction. The plurality of joining portion rows R are arranged at intervals in the left - right direction. In addition, as Figure 4 shown, the joining portion row R extends in the up - down direction while zigzagging in the left - right direction. That is, as Figure 6 shown, the left - right positions of the joining portions 50 adjacent in the up - down direction are offset.

[0079] On the other hand, the vertical positions of the adjacent joints 50 in the left - right direction are aligned. Thus, as Figure 5A shown, the vertical positions of the spaces through which the waist - circumference elastic member 23 passes between the vertically - adjacent joints 50 are aligned. Therefore, the waist - circumference elastic member 23 can be arranged in the left - right direction. However, it is not limited to this. The vertical positions of the adjacent joints 50 in the left - right direction may be offset, or the waist - circumference elastic member 23 may pass between joints 50 having different vertical positions. In these cases, the ventral waist portion 20 can also be given elasticity in the left - right direction.

[0080] In addition, the ventral waist portion 20 (elastic sheet 40) of the present embodiment has a joint group 50G in which a specified number of joints 50 are densely arranged in each joint row R, and the joint groups 50G are arranged at intervals in the vertical direction. The details of the joint group 50G will be described later.

[0081] As Figure 5A shown, the two joints 50 located on both sides of the waist - circumference elastic member 23 in the vertical direction are also referred to as "joint pair 51" (a pair of joints). The upper joint 50 and the lower joint 50 constituting the joint pair 51 are arranged at an interval GH50 in the vertical direction. The size of this interval GH50 is set to be the same as the outer diameter d1 of the waist - circumference elastic member 23 in the state where the ventral waist portion 20 is maximally elongated in the left - right direction or slightly larger than it (GH50≥d1).

[0082] However, the waist - circumference elastic member 23 thickens as it contracts in the left - right direction. Thus, as Figure 5B shown, the interval GH50 of the joint pair 51 is made smaller than the maximum outer diameter d2 of the waist - circumference elastic member 23 in the state where the waist - circumference elastic member 23 contracts in the left - right direction (that is, the natural state of the ventral waist portion 20) (GH50<d2). In this way, the waist - circumference elastic member 23 in the state of contracting in the left - right direction is clamped between the joint pair 51 (the expansion in the vertical direction is restricted). Therefore, the position (movement) of the waist - circumference elastic member 23 with respect to the outer top sheet 21 and the ventral outer bottom sheet 22 in the left - right direction and the vertical direction is restricted.

[0083] Therefore, even without using an adhesive to fix the waist elastic member 23 to the outer top sheet 21 and the ventral outer bottom sheet 22, the positional deviation of the waist elastic member 23 can be suppressed, and the stretchability of the ventral waist portion 20 can be maintained. That is, by using the joint portion 50, the waist elastic member 23 can be attached to the outer top sheet 21 and the ventral outer bottom sheet 22 without using an adhesive or by reducing the amount of adhesive used. Therefore, the softness reduction of the ventral waist portion 20 (stretchable sheet 40) due to the hardening of the adhesive can be suppressed. In addition, the reduction of the elastic characteristics of the waist elastic member 23 due to the hardening of the adhesive can be suppressed.

[0084] In addition, in the ventral waist portion 20, at the side joint portion SS, the waist elastic member 23 is fixed to the outer top sheet 21 and the ventral outer bottom sheet 22. Specifically, at the time of manufacturing the diaper 1, the side joint portion SS is formed in a state where the waist elastic member 23 in an extended state is sandwiched between the outer top sheet 21 and the ventral outer bottom sheet 22, and the end portion of the waist elastic member 23 is fixed to the side joint portion SS. Therefore, even when the ventral waist portion 20 is greatly extended when wearing the diaper 1, the waist elastic member 23 can be prevented from coming off between the joint pairs 51, and the stretchability of the ventral waist portion 20 can be maintained.

[0085] In addition, the relationship between the interval GH50 of the joint pair 51 and the outer diameters d1, d2 of the waist elastic member 23 is not limited to the above configuration. For example, a part of the waist elastic member 23 may overlap with the joint portion 50 to such an extent that the waist elastic member 23 is not cut. In this case, the waist elastic member 23 is also sandwiched between the joint pairs 51 in a state of contracting in the left-right direction, and its position in the left-right direction and up-down direction with respect to the outer top sheet 21 and the ventral outer bottom sheet 22 is restricted.

[0086] In addition, it is not limited to sandwiching all the waist elastic members 23 (elastic members) arranged in the ventral waist portion 20 (stretchable sheet 40) between the joint pairs 51 to restrict the position. As long as the position of at least a part of the waist elastic members 23 is restricted by the joint pairs 51, the other part of the waist elastic members 23 may be fixed to the outer top sheet 21 and the ventral outer bottom sheet 22 by an adhesive.

[0087] <Regarding the joint portion group 50G and the non-arrangement region Np>

[0088] Figure 7 It is Figure 6An enlarged view of a part of the joint column R in it. As described above, the ventral waist part 20 (elastic sheet 40) has a plurality of joint columns R in which a plurality of joints 50 are arranged in the vertical direction. In the present embodiment, the joints 50 are configured as joint groups 50G, and each joint group 50G includes a plurality of joints 50. Specifically, each joint group 50G is an aggregate of a plurality of joints 50 arranged at intervals in the vertical direction, and refers to a region surrounded by a line extending in the vertical direction connecting the left ends of the joints 50 in the aggregate, a line extending in the vertical direction connecting the right ends of the joints 50, the upper end of the uppermost joint 50, and the lower end of the lowermost joint 50. In addition, as Figure 7 shown, in a state where the ventral waist part 20 is elongated in the left-right direction, the vertical length Lb between the vertically adjacent joints 50 in the joint group 50G is smaller than the left-right length La of the joint 50 (La > Lb).

[0089] Each joint group 50G in the present embodiment includes 8 joints 50, but the number of joints 50 is not limited to this. In addition, it is not necessary that each joint group 50G includes the same number of joints 50. The joints 50 included in the joint group 50G are preferably at least 4 or more, and more preferably 5 or more.

[0090] As an example, in the case of including 4 joints 50, the vertical length Ld of the joint group 50G is preferably at least 1.0 mm or more. In this case, preferably, the vertical length Lm of each joint 50 is 0.1 mm or more, and the vertical length Lb (the length of the above-mentioned interval GH50) between the vertically adjacent joints 50 is 0.25 mm or more. In addition, for example, in the case where the joint group 50G includes 5 joints 50, the vertical length Ld of the joint group 50G is preferably at least 2.0 mm or more. In this case, preferably, the vertical length Lm of each joint 50 is 0.25 mm or more, and the vertical length Lb between the vertically adjacent joints 50 is 0.3 mm or more. In addition, the vertical length Lm of each joint 50 is smaller than the left-right length La.

[0091] In addition, each joint portion group 50G includes at least a pair of joint portions 50 (the above-described joint portion pair 51) that sandwich the waist circumference elastic member 23 (elastic member). Moreover, two or more pairs of paired joint portions 50 may be included in the joint portion group 50G. As in the joint portion group 50G of the present embodiment, by providing a plurality of joint portions 50 for a pair of joint portions 50 that sandwich the waist circumference elastic member 23, even if there is a deviation in the arrangement of the waist circumference elastic member 23 during the manufacturing process, the waist circumference elastic member 23 can be sandwiched and fixed between any other adjacent joint portions 50 in the vertical direction (between other pairs of joint portions 50), and it is possible to suppress being fixed significantly deviated from the elongation direction of the waist circumference elastic member 23. Since the stretchability in the elongation direction of the waist circumference elastic member 23 can be maintained, it is easy to exhibit stable fitting performance during wearing.

[0092] Since each joint portion group 50G of the present embodiment includes eight joint portions 50 respectively, in each joint portion group 50G, there are seven portions between adjacent joint portions 50 in the vertical direction, and the waist circumference elastic member 23 is sandwiched between a pair of joint portions 50 at the central portion in the vertical direction, but the arrangement position of the waist circumference elastic member 23 is not limited thereto, and it may be arranged between other pairs of joint portions 50 in the joint portion group 50G.

[0093] In addition, as Figure 4 shown, since the vertical interval of the waist circumference elastic member 23 becomes shorter at the upper end portion 20A in the vertical direction of the ventral waist portion 20, the length between adjacent joint portion groups 50G in the vertical direction of the upper end portion 20A is also shorter than that of the lower side portion 20B below the upper end portion 20A, and more joint portion groups 50G (joint portions 50) are provided. In addition, Figure 6 and Figure 7 show a part of the joint portion row R in the above-described lower side portion 20B.

[0094] Conventionally, in order to form beautiful wrinkles along the length direction of the product (here, the vertical direction of the diaper 1) when the elastic member (such as the waist circumference elastic member 23) disposed at the waist circumference of a disposable diaper or other underwear-type absorbent article contracts, as described above, a method of forming a plurality of joint portion rows arranged along the vertical direction with a space in the left-right direction has been considered. On the other hand, since the beautifully formed wrinkles along the vertical direction stand up, there is a possibility that the frictional force against the skin becomes higher. In addition, the wrinkles formed in this way are difficult to be compressed, and there is also a possibility of discomfort during wearing.

[0095] Regarding this point, in the present embodiment, the following configuration is provided. In Figure 7 it shows Figure 6Among the plurality of rows of joints R shown, three rows of joints R (the first row of joints R1, the second row of joints R2, and the third row of joints R3) adjacent to each other in the left-right direction. In addition, these three rows of joints R are the rows of joints R in the lower part 20B of the ventral waist part 20( Figure 4 ). As shown in Figure 7 , a plurality of joint groups 50G constitute the first row of joints R1, the second row of joints R2, and the third row of joints R3 along the up-down direction. And when the region between the joint groups 50G adjacent in the up-down direction is set as a non-arrangement region Np where no joint group 50G is arranged, the length Lc in the up-down direction of this non-arrangement region Np is greater than the length Lb in the up-down direction between a pair of joints 50 (Lc > Lb). Further, at a position P1 in the up-down direction, the joints 50 in the first row of joints R1, the joints 50 in the second row of joints R2, and the joints 50 in the third row of joints R3 overlap, and in addition, at another position P2 in the up-down direction, the non-arrangement regions Np in the first row of joints R1, the non-arrangement regions Np in the second row of joints R2, and the non-arrangement regions Np in the third row of joints R3 overlap.

[0096] In this way, the joints 50 in each of the three rows of the first row of joints R1, the second row of joints R2, and the third row of joints R3 adjacent to each other in the left-right direction are formed at a common position (P1) in the up-down direction. Thus, when the waist elastic member 23 contracts, it is easy to form beautiful wrinkles along the up-down direction on both outer sides in the left-right direction of each joint 50. And since no joint group 50G is arranged in the non-arrangement region Np, it is a region that is easily compressed. Such non-arrangement regions Np are also set at a common position in the up-down direction in the three rows of the first row of joints R1, the second row of joints R2, and the third row of joints R3 adjacent to each other in the left-right direction. Therefore, it is easy to form a space along the left-right direction, ensuring flexibility. According to such a configuration, the flexibility of the ventral waist part 20 (the stretchable sheet 40) is improved, and the possibility of discomfort during wearing can be reduced.

[0097] In addition, as shown in Figure 7 , the length Ld in the up-down direction of the joint group 50G is greater than the length La in the left-right direction (Ld > La). In this way, since the joint group 50G becomes longer in the up-down direction, it is easier to form wrinkles (longitudinal wrinkles) along the up-down direction.

[0098] In addition, in Figure 7 , the length Lc in the up-down direction of the non-arrangement region Np is greater than the length Ld in the up-down direction of the joint group 50G (Lc > Ld). In this way, since the length of the non-arrangement region Np where no joint group 50G is arranged is long, more spaces that are easily compressed are formed, and the flexibility is improved.

[0099] Moreover, the length Lc in the vertical direction of the non-arrangement region Np is greater than the length Ld in the vertical direction of the joint portion group 50G, but preferably not more than three times that length Ld. If the non-arrangement region Np without the joint portion group 50G arranged is too long, the unjoined space becomes long, and thus it is difficult to form beautiful wrinkles along the vertical direction during contraction. Therefore, by setting the length Lc in the vertical direction of the non-arrangement region Np to not more than three times the length Ld in the vertical direction of the joint portion group 50G, it is possible to prevent excessive separation between the vertical directions of the joint portion group 50G and promote the formation of wrinkles along the vertical direction by the joint portion group 50G.

[0100] Moreover, as described above, the waistline elastic member 23 is clamped between a pair of joint portions 50, and the interval in the vertical direction between the adjacent waistline elastic members 23, 23 in the vertical direction is preferably 4 mm or more. If the interval between the adjacent waistline elastic members 23, 23 in the vertical direction is too short, the rigidity between the waistline elastic members 23, 23 becomes too high, and there is a possibility of discomfort during wearing. By setting the interval in the vertical direction to 4 mm or more, it is easy to put a finger between the waistline elastic members 23, 23 to pull up the diaper 1 during wearing, and the rigidity is not too high, which can reduce the discomfort during wearing.

[0101] In addition, when the center in the vertical direction between the adjacent waistline elastic members 23, 23 in the vertical direction is set as the center position PL( Figure 7 ), the non-arrangement region Np without the joint portion group 50G arranged is preferably arranged so as to straddle the center position PL, and more preferably, the non-arrangement region Np is arranged to be biased upward relative to the center position PL. The non-arrangement region Np without the joint portion group 50G arranged is a region without a difference in rigidity and is difficult to break. By arranging such a non-arrangement region Np at a position straddling the above center position PL or at a position biased upward relative to the above center position PL, when the wearer puts a finger between the waistline elastic members 23, 23 to pull up the diaper 1, it is possible to make the waistline portion (ventral waistline portion 20, dorsal waistline portion 30) difficult to break.

[0102] Figure 8 It is a diagram for explaining Figure 4 the joint portion row R in the upper end portion 20A shown. As Figure 8 shown, in the upper end portion 20A of the ventral waistline portion 20, the length Lc in the vertical direction of the non-arrangement region Np is smaller than the length Ld in the vertical direction of the joint portion group 50G (Lc < Ld). In the ventral waistline portion 20, the upper end portion 20A is a portion where curling or breakage is likely to occur during wearing. At such a portion, the length of the joint portion group 50G is long, and thus the rigidity is likely to become high, and it is easier to form beautiful wrinkles along the vertical direction. As a result, breakage is difficult to occur, and the fitting property is improved.

[0103] Figure 9 This is a diagram for explaining the joint groups 50G adjacent to each other in the left-right direction. Figure 9 As shown in FIG. 1 , when the area between the adjacent joint part groups 50G in the left-right direction (as an example, Figure 9 When the inter-row non-configuration area NRp is set as one without the configuration of the joint group 50G (such as between the adjacent joint groups 50G of the first joint column R1 and the second joint column R2, between the adjacent joint groups 50G of the second joint column R2 and the third joint column R3, etc.), the length Le of the inter-row non-configuration area NRp in the left-right direction is greater than the length Ld of the joint group 50G in the up-down direction. Assuming that the length Le of the inter-row non-configuration area NRp in the left-right direction is short, when the waist elastic member 23 contracts, the wrinkles along the up-down direction are likely to be thin, and there is a possibility that the skin touch becomes hard. However, by setting the length Le of the inter-row non-configuration area NRp in the left-right direction to be long as in the present embodiment, large wrinkles along the up-down direction are likely to be formed when the waist elastic member 23 contracts, which can improve the skin touch.

[0104] Moreover, the length Le of the inter-row non-configuration region NRp in the left-right direction is greater than the length Ld of the joint group 50G in the up-down direction, but is preferably less than 3 times the length Ld. If the length of the inter-row non-configuration region NRp without the joint group 50G is too long, the unjoined space becomes longer, and thus, it is difficult to form beautiful wrinkles along the up-down direction during contraction. Therefore, by setting the length Le of the inter-row non-configuration region NRp in the left-right direction to less than 3 times the length Ld of the joint group 50G in the up-down direction, it is possible to prevent the joint groups 50G adjacent to each other in the left-right direction from being too separated, and to promote the formation of wrinkles along the up-down direction by the joint group 50G.

[0105] Figure 10 2 is a diagram showing a modified example of the arrangement of the junction row R. Figure 7 as well as Figure 8 In the illustrated embodiment, for the non-configuration area Np in the first joint portion row R1, the non-configuration area Np in the second joint portion row R2, and the non-configuration area Np in the third joint portion row R3, the upper end and the lower end of each non-configuration area Np are at the same position in the vertical direction, that is, each non-configuration area NP overlaps in the vertical direction. However, the configuration positions of the joint portion group 50G and the non-configuration area Np are not limited to this.

[0106] As an example, in Figure 10In the illustrated modified example, the vertical positions of the joint group 50G in the second joint row R2 and the non-arrangement region Np are offset from the vertical positions of the joint group 50G and the non-arrangement region Np in the first joint row R1 and the third joint row R3. Here, among the non-arrangement regions Np in the first joint row R1, the non-arrangement region Np in the second joint row R2, and the non-arrangement region Np in the third joint row R3 that overlap at another vertical position P2' shown in Figure 10 , for the non-arrangement regions Np (two non-arrangement regions) in the first joint row R1 and the second joint row R2, the region that overlaps in the vertical direction is set as the overlapping region Npv, and the region that does not overlap in the vertical direction is set as the non-overlapping region Npg. At this time, it is preferable that the vertical length Lf of the overlapping region Npv is greater than the vertical length Lg of the non-overlapping region Npg (Lf > Lg). Similarly, for the non-arrangement regions Np (two non-arrangement regions) in each of the second joint row R2 and the third joint row R3, it is also preferable that the vertical length Lf of the overlapping region Npv is greater than the vertical length Lg of the non-overlapping region Npg. The unfixed non-arrangement region Np is easily compressed and has no joint 50 provided, so it is a region where it is easy to form a space with a good skin feel. By making the length Lf of the overlapping region Npv where the non-arrangement regions Np overlap greater than the length Lg of the non-overlapping region Npg and arranging the overlapping region Npv along the left-right direction, it is thus easy to ensure a larger space. According to such a configuration, the flexibility can be improved.

[0107] Figure 11 It is a diagram showing a modified example of the joint row R. Figure 11The modified example shown below shows an example of the joint row R of a part of the ventral waist part 20 in the same manner as the above-described embodiment. In this modified example, in each joint row R, in a part of the non-arrangement area Np, there is an auxiliary joint 60 that joins the outer top sheet 21 and the ventral outer bottom sheet 22 (a pair of sheets) differently from the joint 50. Examples of the joining method relying on the auxiliary joint 60 include heat melting, ultrasonic welding, or a joining method relying on an adhesive. If the interval between adjacent joint groups 50G in the vertical direction (the so-called length of the non-arrangement area Np in the vertical direction) becomes long, it becomes difficult to form regular wrinkles along the vertical direction formed by the pair of sheets when the waist elastic member 23 contracts. In this case, as in this modified example, by providing the auxiliary joint 60 in a part of the non-arrangement area Np, it becomes easy to form regular wrinkles along the vertical direction. In addition, as long as such an auxiliary for forming regular wrinkles is achieved, thus, as shown in this modified example, the length Lh in the left-right direction of the auxiliary joint 60 may also be smaller than the length La in the left-right direction of the joint group 50G. By shortening the length Lh of the auxiliary joint 60, a decrease in skin feel can be avoided, and softness can be easily maintained. In addition, without being limited thereto, the length Lh of the auxiliary joint 60 may also be set to be larger than the length La of the joint group 50G. Moreover, the auxiliary joint 60 of this modified example is formed in a rectangular shape, but the shape is not limited thereto, and any shape can be adopted.

[0108] Figure 12 It is a figure which shows another modification of the joint row R. Figure 12 The modified example shown below shows the joint row R of a part of the ventral waist part 20 in the same manner as the above-described embodiment. The joint group 50G of the above-described present embodiment has a plurality of joints 50 of the same size, but is not limited thereto. In Figure 12 In the modified example shown, the sizes of the joints 50 arranged at both ends in the vertical direction among the joint group 50G are formed larger than the other joints 50. Specifically, when the joints 50 arranged at both ends in the vertical direction among the joint group 50G are respectively set as the upper-end joint 50up and the lower-end joint 50dw, the lengths Li and Lj in the vertical direction of the upper-end joint 50up and the lower-end joint 50dw are larger than the length Lk in the vertical direction of the joints 50 other than the upper-end joint 50up and the lower-end joint 50dw in the same joint group 50G.

[0109] In the joint portion group 50G, the waist circumference elastic member 23 is disposed between any pair of joint portions 50 in the joint portion group 50G. However, at this time, during the manufacturing process, when it is to be disposed between the upper and lower ends in the vertical direction, that is, between a pair of joint portions 50 including the uppermost joint portion 50 or the lowermost joint portion 50, there is a possibility that it may be disposed at a displaced position. In this regard, by setting the vertical lengths Li and Lj of the joint portions 50 (the upper end joint portion 50up and the lower end joint portion 50dw) at both ends in the vertical direction of the joint portion group 50G to be long, the waist circumference elastic member 23 that is excessively displaced can be cut off by the upper end joint portion 50up or the lower end joint portion 50dw, and the waist circumference elastic member 23 can be prevented from being disposed at an unexpected position.

[0110] In addition, Figures 6 to 9 shows the state when the ventral waist portion 20 (stretchable sheet 40) elongates in the left-right direction. The non-arrangement region Np is a region where the joint portions 50 are not arranged, that is, an unfixed region, and thus is a region where a space is easily formed by compression. More specifically, when the waist circumference elastic member 23 (33) (elastic member) contracts, wrinkles are formed along the vertical direction on both sides in the left-right direction of the joint portion group 50G on the diaper 1, and the wrinkles along the vertical direction also extend on both sides in the left-right direction of the non-arrangement region Np. Also, when the waist circumference elastic member 23 contracts, in each non-arrangement region Np (for example, the non-arrangement region Np in the first joint portion row R1, the non-arrangement region Np in the second joint portion row R2, and the non-arrangement region Np in the third joint portion row R3), a protruding portion (not shown) is formed where the outer top sheet 21 and the ventral outer bottom sheet 22 (a pair of sheets) protrude toward one side or the other side in the thickness direction of the ventral waist portion 20 (stretchable sheet 40). The protruding portion may be such that the two sheets (the outer top sheet 21 and the ventral outer bottom sheet 22) protrude in the same direction (one side or the other side), or alternatively, the two sheets may protrude in different directions (one sheet toward one side and the other sheet toward the other side). Since there are no joint portions 50 in the protruding portion, the skin feel is good, and by forming a plurality of such protruding portions with good skin feel, the softness of the ventral waist portion 20 (stretchable sheet 40) is improved.

[0111] Figure 13 is a view for explaining the adhesive portion 70 of the folded-back portion 22r. The diaper 1 has a folded-back portion 22r, 32r (refer to Figure 2 and Figure 3)。The folded-back portions 22r and 32r are respectively adhered to the inner sides (skin sides) of the waist portions 20 and 30 by an adhesive portion 70 coated with an adhesive such as a hot-melt adhesive. As an example of the coating pattern of this adhesive, the circular pattern shown in Figure 13 can be exemplified, but it is not limited thereto, and other coating patterns may also be used.

[0112] Moreover, as shown in Figure 13 , for the diaper 1, if a portion other than the adhesive portion 70 in the folded-back portion 22r is set as a non-adhesive portion, the non-adhesive portion and the non-disposed area Np have an overlapping portion in a plan view. The overlapping portion of the non-adhesive portion in the folded-back portion 22r and the non-disposed area Np is an area where the number of laminated sheets of the material increases in the thickness direction and there are no adhesive portions 70 and joining portions 50 where the materials are not adhered, and this overlapping portion is a portion that is more easily compressed. By providing such a portion that is easily compressed, the skin feel of the waist portion 20 can be improved.

[0113] In addition, the diaper 1 may have, in at least one of the pair of waist portions 20 and 30, another sheet (not shown) different from the pair of sheets (the outer topsheet 21 and the ventral (dorsal) outer backsheet 22 (32)) that overlaps in the thickness direction ( Figure 1 in the pant type, it is the front-back direction). This other sheet is preferably adhered to the skin sides of the pair of sheets by an adhesive portion (not shown) coated with an adhesive such as a hot-melt adhesive like the adhesive portion 70 shown in Figure 13 . When the portion where such a pair of sheets and the other sheet are arranged to overlap in the thickness direction is set as a laminated portion, by making the non-adhesive portion other than the adhesive portion in this laminated portion and the non-disposed area Np have an overlapping portion in a plan view, similar to the above-mentioned folded-back portion 22r, the skin feel of the waist portion 20 (30) can be easily improved. That is, the overlapping portion of the non-adhesive portion in the laminated portion and the non-disposed area Np is an area where the number of laminated sheets of the material increases and there are no joining (adhesive) joining portions (adhesive portions), and it is a portion that is easily compressed. By providing such a portion that is easily compressed, the skin feel can be improved.

[0114] In addition, returning to Figure 13 , the folded-back portion 22r also has an overlapping portion of the adhesive portion 70 that adheres the folded-back portion 22r and the non-disposed area Np in a plan view. The adhesive portion 70 is an area where the rigidity becomes higher due to the coating of the adhesive, and the overlapping portion of such an adhesive portion 70 and the non-disposed area Np is a portion that is more easily compressed than the overlapping portion of the adhesive portion 70 and the joining portion group 50G in a plan view. Therefore, by having the overlapping portion of the adhesive portion 70 and the non-disposed area Np, the adhesive portion 70 is not too hard, and a decrease in skin feel can be avoided.

[0115] In addition, as Figure 13 shown, the bonding portion 70 of the folded-back portion 22r is provided at a position away from the side joint portion SS in the left-right direction. Specifically, the bonding portion 70 in the folded-back portion 22r is preferably arranged at an interval of about 10 mm to 20 mm inward from the side joint portion SS in the left-right direction. The side joint portion SS is a region where the rigidity becomes higher. By not providing the bonding portion 70 near the side joint portion SS, it is easy to form a flexible wrinkle along the joint row R relatively large near the side joint portion SS. Thus, a decrease in skin touch feeling can be avoided even near the side joint portion SS with high rigidity.

[0116] In addition, in the present embodiment, the diaper 1 has a portion where the absorbent main body 10 and the non-arrangement region Np overlap in a plan view (this overlapping portion is not shown in Figure 4 but the joint group 50G and the non-arrangement region Np are also continuously provided on the non-skin surface side of the absorbent main body 10 in Figure 4 ). The absorbent main body 10 is a region with higher rigidity, and the portion that overlaps with the non-arrangement region Np in a plan view is a portion where the waist regions 20 and 30 are easily compressed. Thus, when the wearer wears the diaper 1, discomfort can be reduced.

[0117] In addition, as described above, the ventral waist region 20 and the dorsal waist region 30 of the present embodiment are composed of the outer cover top sheet 21 and the ventral outer cover bottom sheet 22 or the outer cover top sheet 21 and the dorsal outer cover bottom sheet 32 joined by a plurality of joints 50. However, the total value of the unit area weights of the outer cover top sheet 21 and the ventral outer cover bottom sheet 22 (or the outer cover top sheet 21 and the dorsal outer cover bottom sheet 32) constituting such a waist region (ventral and dorsal waist regions 20, 30) is preferably 30 g / m 2 Hereinafter. By setting the total value of the unit area weights of the sheet members (outer cover top sheet 21 and ventral outer cover bottom sheet 22 or outer cover top sheet 21 and dorsal outer cover bottom sheet 32) constituting the waist region (ventral and dorsal waist regions 20, 30) to 30 g / m 2 Hereinafter, it is easy to pull up the diaper 1 during wearing. In addition, if the total value of the unit area weight is increased, the rigidity becomes higher. If a welding method is used to form a plurality of joints 50 in such a sheet member, there is a possibility that the rigidity becomes too high. By setting it to be less than or equal to the above-mentioned total value of the unit area weight, the rigidity will not be too high, and discomfort during wearing can be reduced.

[0118] In addition, the diaper 1 of the present embodiment is as Figure 2As shown, the outer package 18 has an integral shape that continues from the ventral waist portion 20 to the dorsal waist portion 30. Therefore, when the diaper 1 is grasped at the ventral waist portion 20 or the dorsal waist portion 30 and pulled up during wearing, the upward pulling force is transmitted to the crotch portion 35, making it easier to pull up the crotch portion 35. As a result, the fit of the product is further improved.

[0119] === Others ===

[0120] The purpose of the above-described embodiments is to facilitate the understanding of the present invention and does not provide a limiting interpretation of the present invention. The present invention can be modified and improved without departing from its concept, and of course, the present invention also includes its equivalent structures.

[0121] Description of Reference Numerals

[0122] 1 Pant-type disposable diaper

[0123] 10 Absorbent main body

[0124] 11 Absorbent core

[0125] 12 Topsheet

[0126] 13 Backsheet

[0127] 14 Outer package sheet

[0128] 15 Leg elastic member

[0129] 16 Leakage prevention wall elastic member

[0130] 18 Outer package

[0131] 20 Waist portion (ventral waist portion)

[0132] 20A Upper end portion

[0133] 20B Lower side portion

[0134] 21 Outer package topsheet

[0135] 22 Ventral outer package backsheet

[0136] 22r Folded-back portion

[0137] 23 Waist elastic member

[0138] 30 Waist portion (dorsal waist portion)

[0139] 32 Dorsal outer package backsheet

[0140] 32r Folded-back portion

[0141] 33 Waist elastic member

[0142] 34 Rear leg elastic member

[0143] 35 Lower crotch

[0144] 40 Stretchable sheet

[0145] 50 Joint

[0146] 50dw Lower end joint

[0147] 50G Joint group

[0148] 50up Upper end joint

[0149] 51 Joint pair

[0150] 60 Auxiliary joint

[0151] 70 Adhesive part

Claims

1. A stretchable sheet having an up-down direction and a left-right direction that intersect each other, between a pair of sheets joined by a plurality of joining portions, a plurality of elastic members capable of stretching in the left-right direction are arranged at intervals in the up-down direction, and characterized in that, the stretchable sheet has a group of joining portions including at least a pair of the joining portions that sandwich the elastic members, a plurality of the groups of joining portions constitute a first joining portion row, a second joining portion row, and a third joining portion row along the up-down direction, in a state of being stretched in the left-right direction, the length in the up-down direction between the joining portions adjacent in the up-down direction in the group of joining portions is smaller than the length in the left-right direction of the joining portions, when a region between the groups of joining portions adjacent in the up-down direction is set as a non-arrangement region where the groups of joining portions are not arranged, the length in the up-down direction of the non-arrangement region is larger than the length in the up-down direction between the pair of the joining portions, the first joining portion row, the second joining portion row, and the third joining portion row are adjacent in the left-right direction, at one position in the up-down direction, the joining portions in the first joining portion row, the joining portions in the second joining portion row, and the joining portions in the third joining portion row overlap, at another position in the up-down direction, the non-arrangement regions in the first joining portion row, the non-arrangement regions in the second joining portion row, and the non-arrangement regions in the third joining portion row overlap.

2. The stretchable sheet according to claim 1, characterized in that, in a state of being stretched in the left-right direction, the length in the up-down direction of the group of joining portions is larger than the length in the left-right direction.

3. The stretchable sheet according to claim 1 or 2, characterized in that, in a state of being stretched in the left-right direction, among two of the non-arrangement regions in the non-arrangement regions in the first joining portion row, the non-arrangement regions in the second joining portion row, and the non-arrangement regions in the third joining portion row that overlap at the another position, when a region that overlaps in the up-down direction is set as an overlapping region and a region that does not overlap in the up-down direction is set as a non-overlapping region, the length in the up-down direction of the overlapping region is larger than the length in the up-down direction of the non-overlapping region.

4. The stretchable sheet according to claim 1 or 2, characterized in that, in a state of being stretched in the left-right direction, the length in the up-down direction of the non-arrangement region is larger than the length in the up-down direction of the group of joining portions.

5. The stretchable sheet according to claim 4, characterized in that, the length in the up-down direction of the non-arrangement region is 3 times or less the length in the up-down direction of the group of joining portions.

6. The stretchable sheet according to claim 1 or 2, characterized in that, in a state of being stretched in the left-right direction, the length in the up-down direction of the non-arrangement region is smaller than the length in the up-down direction of the group of joining portions.

7. The stretchable sheet according to claim 1 or 2, characterized in that, In a state of being elongated in the above-described left-right direction, When a region between the above-described groups of engaging portions adjacent in the above-described left-right direction is set as an inter-column non-arrangement region where the above-described groups of engaging portions are not arranged, The length of the above-described inter-column non-arrangement region in the above-described left-right direction is greater than the length of the above-described groups of engaging portions in the above-described up-down direction.

8. The stretchable sheet according to claim 7, characterized in that The length of the above-described inter-column non-arrangement region in the above-described left-right direction is 3 times or less the length of the above-described groups of engaging portions in the above-described up-down direction.

9. The stretchable sheet according to claim 1 or 2, characterized in that An auxiliary engaging portion for joining the above-described pair of sheets, which is different from the above-described engaging portion, is provided in a part of the above-described non-arrangement region.

10. The stretchable sheet according to claim 1 or 2, characterized in that In a state where the above-described elastic member is contracted, In the above-described non-arrangement regions in the above-described first engaging portion row, the above-described second engaging portion row, and the above-described third engaging portion row that overlap at another position in the above-described up-down direction, a protruding portion that protrudes toward one side or the other side in the thickness direction of the above-described stretchable sheet is formed.

11. The stretchable sheet according to claim 1 or 2, characterized in that When the above-described engaging portions arranged at both ends in the above-described up-down direction among the above-described groups of engaging portions are respectively set as an upper-end engaging portion and a lower-end engaging portion, the lengths of the upper-end engaging portion and the lower-end engaging portion in the above-described up-down direction are greater than the lengths of the above-described engaging portions other than the upper-end engaging portion and the lower-end engaging portion among the above-described groups of engaging portions in the above-described up-down direction.

12. A panty-type absorbent article, the panty-type absorbent article having the stretchable sheet according to claim 1 or 2, characterized in that The above-described panty-type absorbent article has an up-down direction, a left-right direction, and a front-back direction that intersect each other, The above-described panty-type absorbent article has an absorbent main body and a pair of waist regions, The above-described stretchable sheet is provided in at least one of the above-described pair of waist regions, The above-described up-down direction of the above-described stretchable sheet is along the above-described up-down direction of the above-described panty-type absorbent article, the above-described left-right direction of the above-described stretchable sheet is along the above-described left-right direction of the above-described panty-type absorbent article, and the thickness direction of the above-described stretchable sheet is along the above-described front-back direction of the above-described panty-type absorbent article, The above-described pair of waist regions are joined by a pair of side engaging portions at both side portions in the above-described left-right direction, At least one of the above-described pair of waist regions has a laminated portion where the above-described pair of sheets and a sheet different from the above-described pair of sheets are adhered by an adhesive portion in a manner of overlapping in the above-described front-back direction, or a folded-back portion where at least one of the above-described pair of sheets is folded back toward the inner surface side of the above-described waist region and adhered by an adhesive portion, The above-described panty-type absorbent article has a non-adhesive portion other than the above-described adhesive portion in the above-described laminated portion or a portion where a non-adhesive portion other than the above-described adhesive portion in the above-described folded-back portion overlaps with the above-described non-arrangement region in a top view.

Images