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 welded sections (50), a first welded section row (Ra1) has a first convex section (51) and a second convex section (52) that protrude toward one side in the left-right direction, a second welded section row (Ra2) has a third convex section (53) that protrudes toward the other side in the left-right direction, and in an extended state, the first convex section (51) and the second convex section (52) protrude toward the other side in the left-right direction. At least a portion of a welded portion (503) located closest to the other side in the left-right direction in the third convex portion (53) is located further toward the other side in the left-right direction than a line (La) connecting ends of welded portions (501, 502) located closest to the one side in the left-right direction in the first convex portion (51) and the second convex portion (52) in the left-right direction.

Description

Technical Field

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

[0002] For stretchable sheets used in underwear type absorbent articles, etc., an operation of joining an elastic member in a stretched state to a sheet and contracting the elastic member to form gathers on the sheet is generally performed. In Patent Document 1, the purpose is to form gathers (pleats) extending continuously in a direction perpendicular to the stretching direction of the elastic member on the stretchable sheet. Therefore, two sheets sandwiching the elastic member are partially joined by heat-fused portions arranged in a staggered manner or heat-fused portions forming a row along a direction perpendicular to the stretching direction.

[0003] Prior Art Literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2007-14802 Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, as in Patent Document 1, if a plurality of heat fusion portions are arranged linearly in a direction perpendicular to the stretching direction, the rigidity of the stretchable sheet in the perpendicular direction may be increased, thereby possibly reducing the flexibility of the sheet.

[0008] Furthermore, a user who sees a stretchable sheet having gathers extending continuously in a direction perpendicular to the stretching direction may have an impression that the stretchable sheet is highly stretchable and has a strong sense of tightness.

[0009] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a stretchable sheet and a pull-on absorbent article which have softness and are easy to obtain a soft fitting impression.

[0010] Solutions to Solve Problems

[0011] The main invention for achieving the above-mentioned purpose is a stretchable sheet, which has an up-down direction and a left-right direction that intersect each other, and a plurality of elastic members that can stretch along the left-right direction are arranged at intervals in the up-down direction between a pair of sheets joined by a plurality of welded portions, characterized in that each of the elastic members is restricted in position in the left-right direction relative to the pair of sheets by being sandwiched between two of the welded portions adjacent to each other in the up-down direction when contracted in the left-right direction, and the stretchable sheet has a plurality of welded portion rows in which a plurality of the welded portions are arranged in the up-down direction, and the plurality of welded portion rows include: a first welded portion row; and the left welded portion row located in the first welded portion row. A second weld portion row next to one side in the right direction, the first weld portion row having a first convex portion and a second convex portion protruding toward the one side in the left-right direction and adjacent to each other in the up-down direction, the second weld portion row having a third convex portion protruding toward the other side in the left-right direction, in a state extended along the left-right direction, compared to a line connecting end portions of the weld portion at the other side in the left-right direction where the first convex portion and the second convex portion are respectively located at positions closest to the one side in the left-right direction, at least a portion of the weld portion at which the third convex portion is located at a position closest to the other side in the left-right direction is located at the other side in the left-right direction.

[0012] Other features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[0013] Effects of the Invention

[0014] According to the present invention, a shrinkable sheet and a pull-on absorbent article which have softness and are easy to obtain a soft fitting impression can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic perspective view of the underpants-type disposable diaper 1.

[0016] Figure 2 This is a schematic plan view of the diaper 1 in the unfolded and stretched state as viewed from the skin side of the wearer.

[0017] Figure 3 yes Figure 2 A schematic cross-sectional view at A-A in FIG.

[0018] Figure 4 It is an explanatory diagram of the welded portion rows Ra and Rb provided in the abdominal waistline portion 20 .

[0019] Figure 5A as well as Figure 5B This is an explanatory diagram of the attachment function of the waist elastic member 23.

[0020] Figure 6 It is an explanatory diagram of the welded portion row Ra included in the first welded region A1.

[0021] Figure 7 It is an explanatory diagram of the welded portion row Ra included in the first welded region A1.

[0022] Fig. 8A as well as Figure 8B It is an explanatory diagram of the fusion bonded portion row Rb included in the second fusion bonded area A2.

[0023] Fig. 9 The figure schematically shows the gathers 61 and 62 formed in the abdominal waistline portion 20 .

[0024] Fig.10 This is a diagram illustrating a photograph of the wrinkles 61 formed in the first expansion and contraction region A1. DETAILED DESCRIPTION

[0025] At least the following matters will be made clear from the description of this specification and the accompanying drawings.

[0026] Mode 1 is a stretchable sheet having mutually intersecting up-down directions and left-right directions, wherein between a pair of sheets joined by a plurality of welded portions, a plurality of elastic members that can stretch in the left-right direction are arranged at intervals in the up-down direction, and characterized in that each of the elastic members is restricted in position in the left-right direction relative to the pair of sheets by being sandwiched between two of the welded portions adjacent in the up-down direction when contracted in the left-right direction, and the stretchable sheet has a plurality of welded portion rows in which a plurality of the welded portions are arranged in the up-down direction, and the plurality of welded portion rows include: a first welded portion row; and a welded portion row located in the left-right direction of the first welded portion row. The second welding portion row is next to the right side, the first welding portion row has a first convex portion and a second convex portion which protrude toward the one side of the left-right direction and are adjacent to each other in the up-down direction, the second welding portion row has a third convex portion which protrudes toward the other side of the left-right direction, and in a state extended along the left-right direction, compared with a line connecting end portions of the welding portion on the other side of the left-right direction where the first convex portion and the second convex portion are respectively located closest to the one side of the left-right direction, at least a portion of the welding portion where the third convex portion is located closest to the other side of the left-right direction is located on the other side of the left-right direction.

[0027] According to the first embodiment, when the stretch sheet shrinks, the bow-shaped wrinkles along the convex part are easily formed in the vertical direction. Therefore, the stretch sheet is easy to bend in the vertical direction, which can improve the softness of the stretch sheet. In addition, when the stretch sheet is stretched, the first welding part row and the second welding part row partially overlap in the left-right direction, so there is a tendency that the height of the convex part becomes higher and the slope of the convex part becomes larger. Therefore, large bow-shaped wrinkles are easily formed, and users who see the wrinkles are likely to have the impression that the stretch sheet is soft and fit.

[0028] Method 2 is a stretchable sheet as described in Method 1, characterized in that the plurality of welded portion rows include a third welded portion row located next to the second welded portion row on the one side of the left-right direction, the third welded portion row includes a fourth protrusion protruding toward the other side of the left-right direction, and in a state extended along the left-right direction, the welded portion at a position where the fourth protrusion is located closest to the other side of the left-right direction compared to the line is located on the one side of the left-right direction.

[0029] According to the second aspect, the welded portion rows can be prevented from being densely arranged in the left-right direction. Therefore, the softness of the stretch sheet in the left-right direction can be prevented from being reduced due to the hardness of the welded portion. In addition, the area of ​​the sheet that becomes the bow-shaped wrinkles can be ensured between the first welded portion row and the second welded portion row, and the bow-shaped wrinkles can be easily formed.

[0030] Mode 3 is a stretchable sheet as described in Mode 1 or Mode 2, characterized in that, in a state stretched along the left-right direction, more than half of the left-right direction of the welding portion where the third convex portion is located closest to the other side in the left-right direction is located on the other side in the left-right direction compared to the line.

[0031] According to the third aspect, the overlapping length of the first and second welded portion rows in the left-right direction becomes longer, so the height of the convex portion becomes higher and the slope of the convex portion tends to become larger. Therefore, large bow-shaped wrinkles are easily formed.

[0032] Mode 4 is a stretchable sheet as described in Mode 3, characterized in that, in a state stretched in the left-right direction, all of the welded portions where the third convex portion is located closest to the other side in the left-right direction relative to the line are located on the other side in the left-right direction.

[0033] According to aspect 4, the overlapping length of the first welded portion row and the second welded portion row in the left-right direction becomes longer, so the height of the convex portion tends to be higher and the slope of the convex portion tends to be larger. Therefore, large bow-shaped wrinkles are easily formed.

[0034] Aspect 5 is the stretchable sheet according to any one of aspects 1 to 4, wherein in a state stretched in the left-right direction, an interval between the first welded portion row and the second welded portion row in the left-right direction is 6 mm or more.

[0035] According to the fifth aspect, compared with the case where the interval between the first welding portion row and the second welding portion row in the left-right direction is less than 6 mm, the welding portion row can be prevented from being densely arranged in the left-right direction. Therefore, it is possible to prevent the softness of the stretch sheet in the left-right direction from being reduced due to the hardness of the welding portion. In addition, the area of ​​the sheet that becomes the bow-shaped fold can be ensured between the first welding portion row and the second welding portion row, and the bow-shaped fold can be easily formed.

[0036] Mode 6 is a stretchable sheet as described in any one of Modes 1 to 5, characterized in that the above-mentioned first protrusion is located at a position higher than the above-mentioned second protrusion in the up-down direction, and in a state stretched along the above-mentioned left-right direction, has: other lines connecting the ends of the above-mentioned other side of the above-mentioned left-right direction of multiple above-mentioned welded portions constituting the above-mentioned second welded portion column; a first intersection point where the above-mentioned other lines intersect with the above-mentioned lines at the above-mentioned upper side; and a second intersection point where the above-mentioned other lines intersect with the above-mentioned lines at the lower side of the above-mentioned up-down direction, and the length in the above-mentioned up-down direction from the end of the above-mentioned other side of the above-mentioned welded portion at the position closest to the above-mentioned one side in the above-mentioned left-right direction to the above-mentioned first intersection point is greater than the length in the above-mentioned up-down direction from the above-mentioned first intersection point to the above-mentioned second intersection point.

[0037] According to the sixth aspect, since the slope of the third convex portion tends to become larger, it is easy to form an arcuate wrinkle with a large slope, and the arcuate wrinkle is easy to be recognized by the user.

[0038] Mode 7 is a stretchable sheet as described in any one of Modes 1 to 6, characterized in that the plurality of elastic members include: a first elastic member; and a second elastic member located next to the lower side of the first elastic member in the up-down direction, and the welded portion on the lower side of the two welded portions sandwiching the first elastic member in the up-down direction is discontinuous with the welded portion on the upper side of the two welded portions sandwiching the second elastic member in the up-down direction.

[0039] According to aspect 7, it is possible to suppress the rigidity of the stretch sheet in the vertical direction from being increased due to the welded portions that are continuous in the vertical direction, and thus it is possible to improve the flexibility of the stretch sheet in the vertical direction.

[0040] Mode 8 is an underpants-type absorbent article, which has a stretch sheet described in any one of Modes 1 to 7, and is characterized in that the underpants-type absorbent article has mutually intersecting up-down directions and left-right directions, and has an absorbent body and a pair of waistline parts, and the stretch sheet is provided on at least one of the pair of waistline parts, the up-down direction of the stretch sheet is along the up-down direction of the underpants-type absorbent article, and the left-right direction of the stretch sheet is along the left-right direction of the underpants-type absorbent article.

[0041] According to the eighth aspect, the arched folds along the convex part are divided in the vertical direction and formed at the waistline, so the waistline is easy to bend in the vertical direction, and the flexibility of the waistline can be improved. In addition, the user who sees the arched folds is easy to have a soft and matching impression of the waistline.

[0042] A ninth aspect is a pull-on absorbent article according to the eighth aspect, wherein the stretch sheet includes a first fused region having a combination of a plurality of first fused portion rows and a plurality of second fused portion rows adjacent to each other in the left-right direction.

[0043] According to aspect 9, a plurality of arch-shaped gathers can be easily formed in the left-right direction at the waistline, and the user can easily have an impression that the waistline is softly matched.

[0044] Mode 10 is a panty-type absorbent article as described in Mode 9, characterized in that the pair of waist portions are joined by a pair of side joints on both sides in the left-right direction, and the first welding area overlaps with at least a portion of the side joints on one side in the left-right direction, and overlaps with at least a portion of the side joints on the other side in the left-right direction.

[0045] According to aspect 10, a plurality of arch-shaped wrinkles are easily formed in the left-right direction over a wide range of the waistline in the left-right direction, and the user is likely to have an impression of a soft fit on the waistline.

[0046] Mode 11 is an underpants-type absorbent article as described in Mode 9 or Mode 10, characterized in that the above-mentioned stretch sheet has a second welding area, and in the above-mentioned second welding area, a plurality of fourth welding part rows are arranged in the above-mentioned left-right direction, and the fourth welding part rows have convex parts that protrude alternately toward the above-mentioned one side and the above-mentioned other side in the above-mentioned left-right direction. When the above-mentioned stretch sheet is stretched along the above-mentioned left-right direction, the above-mentioned fourth welding part rows adjacent to each other along the above-mentioned left-right direction do not overlap in the above-mentioned left-right direction, or the overlapping length in the above-mentioned left-right direction is less than the length in the above-mentioned left-right direction of the above-mentioned welding part at the position where the above-mentioned convex part is located on the most protruding side in the above-mentioned left-right direction, the spacing in the above-mentioned fourth welding part row in the above-mentioned left-right direction is smaller than the spacing in the above-mentioned left-right direction between the above-mentioned first welding part row and the above-mentioned second welding part row, the above-mentioned second welding area is located at the upper end part of the above-mentioned waistline portion with a specified width, and the above-mentioned first welding area is located at a position lower than the above-mentioned second welding area.

[0047] According to aspect 11, in the second welded area, wrinkles close to the wrinkles along the vertical direction are formed at smaller intervals than in the first welded area. Therefore, the user is likely to have the impression that the upper part (second welded area A2) is firmly fitted to the waistline and is unlikely to fall off, and the other parts (first welded area A1) are softly fitted and have a good wearing feeling.

[0048] ===Implementation Method===

[0049] Hereinafter, as a panty-type absorbent article using the stretchable sheet involved in this embodiment, a panty-type disposable diaper for adults is cited as an example to explain the embodiment. However, the panty-type absorbent article is not limited to the above-mentioned structure, and can also be a panty-type disposable diaper for infants or a pant-type sanitary napkin, etc.

[0050] <<Basic structure of underpants type disposable diaper 1>>

[0051] Figure 1 It is a schematic perspective view of a pull-on disposable diaper 1 (hereinafter also referred to as a “diaper”). Figure 2 This is a schematic plan view of the diaper 1 in the unfolded and stretched state as viewed from the skin side of the wearer. Figure 3 yes Figure 2 A schematic cross-sectional view at A-A in FIG.

[0052] The diaper 1 has a vertical direction, a horizontal direction, and a front-back direction that intersect each other, and has a waist opening BH and a pair of leg openings LH. In the vertical direction, the waist opening BH side is set as the upper side, and the side that will become the crotch side of the wearer is set as the lower side. In the front-back direction, the side that will become the belly side of the wearer is set as the front side, and the side that will become the back side is set as the back side. In addition, the diaper 1 is as shown in FIG. Figure 3As shown in the figure, the material is layered in the thickness direction, and the side in contact with the wearer in the thickness direction is set as the skin side, and the opposite side is set as the non-skin side.

[0053] The diaper 1 includes an absorbent body 10 and a pair of waist portions 20, 30. The pair of waist portions 20, 30 are joined to the non-skin side of the absorbent body 10 by adhesive or the like. The waist portion located on the front side of the pair of waist portions 20 is also referred to as the ventral waist portion 20, and the waist portion located on the rear side is also referred to as the dorsal waist portion 30. The ventral waist portion 20 and the dorsal waist portion 30 are joined at both sides in the left-right direction by a pair of side joining portions SS. Examples of the joining method using the side joining portions SS include a joining method using heat fusion, ultrasonic fusion or adhesive, and the like.

[0054] like Figure 3 As shown in the figure, the absorbent body 10 comprises: an absorbent core 11; a liquid-permeable top sheet 12 arranged on the skin side relative to the absorbent core 11; a liquid-impermeable back sheet 13 arranged on the non-skin side relative to the absorbent core 11; and an outer sheet 14. The absorbent core 11 can be any structure as long as it absorbs and retains excrement, and for example, a structure in which a liquid-absorbent material such as pulp fiber or superabsorbent polymer is formed into a predetermined shape can be exemplified. In addition, the absorbent core 11 can also be covered with a liquid-permeable sheet such as tissue paper or nonwoven fabric.

[0055] like Figure 2 As shown in the figure, a leg elastic member 15 (e.g., rubber thread) that stretches and contracts along the length direction of the absorbent body 10 may be provided on both sides of the absorbent body 10 in the left-right direction. Furthermore, a leak-proof wall that can stand up toward the skin side may be provided at a position that is closer to the inside of the leg elastic member 15 in the left-right direction. The leak-proof wall is formed, for example, by folding back both sides of the outer sheet 14 in the left-right direction toward the inside of the left-right direction in a manner that is located on the skin side of the top sheet 12, and providing a leak-proof wall elastic member 16 (e.g., rubber thread) that stretches and contracts in the length direction at the folded-back position.

[0056] In the present embodiment, the part overlapping with the side joint part SS in the up-down direction is set as the waistline part 20, 30, and the ventral waistline part 20 and the dorsal waistline part 30 are rectangular parts in a top view. On the lower crotch side of the dorsal waistline part 30, a roughly trapezoidal extension part 30E is provided. The wearer's buttocks can be covered by the extension part 30E. In the following description, the dorsal waistline part 30 and the extension part 30E are also referred to as the dorsal outerwear part 30, 30E. However, it is not limited to the above-mentioned structure, for example, it can also be a structure without the extension part 30E on the dorsal side, and it can also be a structure with a part extending from the ventral waistline part 20 toward the lower crotch side.

[0057] The ventral waistline portion 20 and the back outerwear portion 30, 30E respectively have skin side sheets 21, 31, non-skin side sheets 22, 32 and waist elastic components 23, 33 (e.g., rubber threads) that can be stretched in the left and right directions. A plurality of waist elastic components 23, 33 are arranged at intervals in the vertical direction between the skin side sheets 21, 31 and the non-skin side sheets 22, 32.

[0058] As the skin side sheets 21, 31 and the non-skin side sheets 22, 32, soft sheet members are preferred, and examples thereof include spunbond nonwoven fabrics, meltblown nonwoven fabrics, SMS (spunbond / meltblown / spunbond) nonwoven fabrics, etc. The constituent fibers of the nonwoven fabrics are not limited to single fibers of polypropylene (PP), which is a representative example of thermoplastic resins, but single fibers of other thermoplastic resins such as polyethylene (PE) may be used, and composite fibers having a sheath-core structure of PE and PP may also be used.

[0059] The basic structure of the diaper 1 is described above, but the structure of the diaper 1 is only an example and is not limited to this. For example, in the diaper 1 of this embodiment, the ventral waistline portion 20 and the dorsal outer covering portions 30, 30E are composed of independent components, and the non-skin side of the absorbent body 10 is exposed in the crotch portion. This is not limited to this. For example, it is also possible to have an outer covering member composed of three components, namely, the ventral waistline portion 20, the dorsal outer covering portions 30, 30E, and the crotch portion connecting them, or it is also possible to have an outer covering member composed of one component continuous from the ventral waistline portion 20 to the dorsal waistline portion 30.

[0060] <<About the waistline portions 20 and 30 (elastic sheet 40)>>

[0061] Figure 4 It is an explanatory diagram of the welded portion rows Ra and Rb provided in the abdominal waistline portion 20 . Figure 5A as well as Figure 5B This is an explanatory diagram of the attachment function of the waist elastic member 23. Figure 6 as well as Figure 7 It is an explanatory diagram of the welded portion row Ra included in the first welded region A1. Fig. 8A as well as Figure 8B It is an explanatory diagram of the fusion bonded portion row Rb included in the second fusion bonded area A2. Fig. 9 The figure schematically shows the gathers 61 and 62 formed in the abdominal waistline portion 20 . Fig.10 This is a diagram illustrating a photograph of the wrinkles 61 formed in the first expansion and contraction region A1.

[0062] Figure 4 , Figure 6 , Figure 7 , Fig. 8A as well as Figure 8BThe state of the ventral waistline portion 20 (elastic sheet 40) when stretched in the left-right direction is shown. The state in which the waistline portion 20, 30 or the elastic sheet 40 is stretched in the left-right direction means that the waistline portion 20, 30 or the elastic sheet 40 is stretched to such an extent that wrinkles are not substantially visible on the waistline portion 20, 30 or the elastic sheet 40, and the size of each member (such as the skin side sheet 21, etc.) constituting the waistline portion 20, 30 or the elastic sheet 40 is stretched to a length that is consistent with or close to the size of the member alone (i.e., the size of the elastic member when it is not elastic).

[0063] <Regarding the Position Limitation of the Waist Elastic Member 23>

[0064] The ventral waistline portion 20 and the dorsal waistline portion 30 are composed of a stretch sheet 40, and the stretch sheet 40 is provided with a plurality of waist elastic members 23, 33 (elastic members) that can stretch in the left-right direction at intervals in the vertical direction between the skin side sheets 21, 31 and the non-skin side sheets 22, 32 joined by a plurality of welded portions 50 (between a pair of sheets). Figure 6 As shown, the skin side sheets 21, 31 and the non-skin side sheets 22, 32 are intermittently joined by a plurality of welded portions 50 discretely arranged in the vertical direction and the horizontal direction. The welded portions 50 can be formed by a known welding method such as ultrasonic welding or heat welding.

[0065] The pair of sheets joined by the welding part 50 may be two independent sheets like the skin side sheets 21, 31 and the non-skin side sheets 22, 32 of the present embodiment, or may be a sheet formed into two layers by folding back one sheet. In addition, the welding part 50 is not limited to joining only a pair of sheets sandwiching the waist elastic members 23, 33, but may also join three or more layers of sheets together with the sheets stacked on the pair of sheets.

[0066] Since the abdominal waistline portion 20 and the dorsal waistline portion 30 have substantially the same configuration, the abdominal waistline portion 20 will be described below as a representative of the two.

[0067] The abdominal waistline portion 20 (elastic sheet 40) has a plurality of welded portion rows Ra and Rb in which a plurality of welded portions 50 are arranged in the vertical direction. The plurality of welded portion rows Ra and Rb are arranged at intervals D3 and D4 in the horizontal direction. Figure 4 As shown in FIG. 1 , the welded portion rows Ra and Rb of the present embodiment extend in the vertical direction while zigzagging in the horizontal direction. Figure 6 As shown in FIG. 1 , the positions of the welded portions 50 adjacent to each other in the vertical direction are shifted in the horizontal direction.

[0068] On the other hand, the positions of the welded portions 50 adjacent to each other in the left-right direction in the vertical direction are aligned. Figure 5AAs shown in the figure, the vertical positions of the spaces through which the waist elastic members 23 pass between the welded portions 50 adjacent in the vertical direction are aligned, so that the waist elastic members 23 can be arranged in the left-right direction. However, the present invention is not limited thereto, and the vertical positions of the welded portions 50 adjacent in the left-right direction may be staggered, or the waist elastic members 23 may pass between welded portions 50 at different vertical positions. In these cases, the ventral waist portion 20 can also be provided with stretchability in the left-right direction.

[0069] like Figure 5A As shown in the figure, the two welds 50 located on both sides of the waist elastic member 23 in the vertical direction are also referred to as a "weld pair 50S". The upper weld 50 and the lower weld 50 constituting the weld pair 50S are arranged in the vertical direction with a gap GH50 therebetween. The size of the gap GH50 is set to be the same as or slightly larger than the outer diameter D1 of the waist elastic member 23 in the state where the ventral waist portion 20 is stretched to the maximum in the left-right direction (GH50 ≥ D1).

[0070] However, the waist elastic member 23 becomes thicker as it contracts in the left-right direction. Figure 5B As shown, the interval GH50 of the welding portion pair 50S is made smaller than the maximum outer shape D2 of the waist elastic member 23 in the state where the waist elastic member 23 is contracted in the left and right directions (that is, the natural state of the abdominal waist portion 20) (GH50<D2). By such a configuration, the waist elastic member 23 in the state of contraction in the left and right directions is sandwiched by the welding portion pair 50S in the up and down direction (the expansion in the up and down direction is limited). Therefore, the position (activity) of the waist elastic member 23 in the left and right directions and the up and down directions relative to the skin side sheet 21 and the non-skin side sheet 22 is limited.

[0071] Therefore, even if the waist elastic member 23 is fixed to the skin side sheet 21 and the non-skin side sheet 22 without using an adhesive, the positional deviation of the waist elastic member 23 can be suppressed, and the elasticity of the ventral waist portion 20 can be maintained. That is, by using the welded portion 50, the waist elastic member 23 can be attached to the skin side sheet 21 and the non-skin side sheet 22 without using an adhesive or with a reduced amount of adhesive. Therefore, the reduction in the softness of the ventral waist portion 20 (elastic sheet 40) due to the hardening of the adhesive can be suppressed. In addition, the reduction in the elastic properties of the waist elastic member 23 due to the hardening of the adhesive can be suppressed.

[0072] In addition, in the ventral waist circumference portion 20, the waist elastic member 23 is fixed to the skin side sheet 21 and the non-skin side sheet at the side joint portion SS. Specifically, when the diaper 1 is manufactured, the waist elastic member 23 in the stretched state is sandwiched between the skin side sheet 21 and the non-skin side sheet 22 to form the side joint portion SS, and the end of the waist elastic member 23 is fixed to the side joint portion SS. Therefore, even if the ventral waist circumference portion 20 is greatly stretched when the diaper 1 is worn, the waist elastic member 23 can be prevented from being separated from between the welding portion pair 50S, and the elasticity of the ventral waist circumference portion 20 can be maintained.

[0073] In addition, the relationship between the interval GH50 of the welding part pair 50S and the outer diameters D1 and D2 of the waist elastic member 23 is not limited to the above-mentioned structure. For example, it can also be set to a degree that the waist elastic member 23 is not cut so that a part of the waist elastic member 23 overlaps with the welding part 50. In this case, the waist elastic member 23 is sandwiched between the welding part pair 50S in a state of contraction in the left-right direction, and the position of the left-right direction and the up-down direction relative to the skin side sheet 21 and the non-skin side sheet 22 is restricted.

[0074] In addition, it is not limited to that all waist elastic members 23 (elastic members) arranged in the ventral waist portion 20 (elastic sheet 40) are clamped by the welding portion pair 51 and the position is restricted. As long as at least a part of the waist elastic members 23 is restricted in position by the welding portion pair 51, another part of the waist elastic members 23 can also be fixed to the skin side sheet 21 and the non-skin side sheet 22 by an adhesive.

[0075] <About the First Welding Area A1>

[0076] like Figure 4 As shown, the abdominal waistline portion 20 includes a first fused region A1 and a second fused region A2 having welded portion rows Ra and Rb having different shapes or arrangement intervals.

[0077] First, the first fusion region A1 will be described. The first fusion region A1 is located below the second fusion region A2 and is longer in the vertical direction than the second fusion region A2. In the first fusion region A1, a plurality of fusion portion rows Ra having the same arrangement pattern of the fusion portions 50 are arranged in the left-right direction at equal intervals D3. The fusion portion rows Ra extend in the vertical direction while zigzagging in the left-right direction, and have a shape having convex portions alternately convex to one side and the other side in the left-right direction in the vertical direction.

[0078] In addition, in the present embodiment, the shape of the weld 50 is a rectangular shape that is long in the left-right direction, but the shape of the weld 50 is not particularly limited. In addition, in the present embodiment, all the welds 50 belonging to the weld row Ra are of the same shape, but this is not limited to this, and may include a configuration having different shapes. Figure 4 The welded portion rows Ra and Rb shown in the example extend in the vertical direction, but the present invention is not limited thereto. The welded portion rows may extend in a direction inclined relative to the vertical direction so that the upper and lower ends of the welded portion rows are offset in the horizontal direction.

[0079] When the abdominal waistline 20 shrinks in the left-right direction, the rigid weld 50 is difficult to shrink, so the interval between the weld rows Ra adjacent to each other in the left-right direction becomes smaller. In addition, the skin side sheet 21 and the non-skin side sheet 22 located between the weld rows Ra adjacent to each other in the left-right direction bulge outward in the thickness direction, and wrinkles along the shape of the weld rows Ra are easily formed.

[0080] Here, it is assumed that, unlike the welded portion row Ra of the first welded area A1, a welded portion row is formed along a straight line in the vertical direction, that is, a welded portion row in which a plurality of welded portions at the same position in the left-right direction are arranged in the vertical direction. In this case, long straight wrinkles along the vertical direction are easily formed. Such wrinkles act like a tappet, and the rigidity of the ventral waistline portion in the vertical direction becomes higher, and there is a possibility that the flexibility of the ventral waistline portion is reduced. In addition, since the welded portion pairs sandwiching the waist elastic member are concentrated at the same position in the left-right direction, the waist elastic member is likely to be locally close to a part of the wearer, and there is a possibility that wrinkle pressure marks are caused on the skin or the wearing feeling is reduced.

[0081] In contrast, the first weld region A1 has a weld row Ra that meanders in the left-right direction. Therefore, the folds along the curve of the convex portion of the weld row Ra switch directions in the left-right direction and are formed in a divided manner in the up-down direction. Therefore, the first weld region A1 is easily bent in the up-down direction, and the flexibility in the up-down direction is improved.

[0082] Furthermore, if a part of the first weld region A1 is focused on, the first weld region A1 includes: a first weld portion row Ra1; and a second weld portion row Ra2 located next to the first weld portion row Ra1 on one side in the left-right direction. Figure 6 As shown, the first welded portion row Ra1 includes a first convex portion 51 and a second convex portion 52 that protrude toward one side in the left-right direction (the second welded portion row Ra2 side) and are adjacent to each other in the vertical direction. The second welded portion row Ra2 includes a third convex portion 53 that protrudes toward the other side in the left-right direction (the first welded portion row Ra1 side). The third convex portion 53 is located between the first convex portion 51 and the second convex portion 52 in the vertical direction.

[0083] Furthermore, in a state where the abdominal waistline portion 20 is extended in the left-right direction, a line connecting the ends of the other side of the welded portions 501 and 502 where the first convex portion 51 and the second convex portion 52 are located at the most one side in the left-right direction is set as an imaginary line La. At this time, at least a part of the welded portion 503 where the third convex portion 53 of the second welded portion array Ra2 is located at the most other side in the left-right direction is located at a position closer to the other side in the left-right direction than the imaginary line La.

[0084] That is, the imaginary line La corresponds to the bottom side of the convex portion (hereinafter referred to as the fifth convex portion 55) of the first welded portion row Ra1 convex toward the other side in the left-right direction, and the third convex portion 53 enters the inner side (the other side in the left-right direction) of the imaginary line La. In other words, the height H (the length in the left-right direction) of the fifth convex portion 55 is set to be larger than the interval D3 in the left-right direction between the first welded portion row Ra1 and the second welded portion row Ra2 so that the first welded portion row Ra1 and the second welded portion row Ra2 partially overlap in the left-right direction (H>D3).

[0085] Therefore, compared with the case where the third protrusion 53 is located outside (on one side in the left-right direction) of the imaginary line La, when the abdominal waistline portion 20 contracts, the fifth protrusion 55 and the third protrusion 53 are more likely to approach each other. Therefore, the unwelded sheet portion between the fifth protrusion 55 and the third protrusion 53 bulges outward in the thickness direction along the fifth protrusion 55 and the third protrusion 53. The sheet portion bulging outward is more likely to fall toward the bottom side (on one side in the left-right direction) of the fifth protrusion 55, and as a result, as shown in FIG. Fig. 9 or Fig.10 As shown in the figure, the arched (curved) wrinkles 61 are easily formed along the convex portions of the welded portion row Ra.

[0086] In addition, as described above, making the height H of the fifth convex portion 55 larger than the interval D3 of the welded portion row Ra in the left-right direction means that the winding amount of the fifth convex portion 55 in the left-right direction is large, and there is a tendency that the slope of the fifth convex portion 55 becomes larger (the inclination is intensified). Therefore, it is easy to form a larger arched fold 61. Therefore, if the arched fold 61 is formed, which is different from the general folds formed in the waistline (for example, the longitudinal folds along the up-and-down direction formed when the waist elastic member is fixed to the sheet by an adhesive), it is easy for the user to recognize.

[0087] In addition, compared with viewing the general longitudinal wrinkles formed in the waistline, the user who views the arched wrinkles 61 is likely to have an impression that the abdominal waistline 20 is softly matched and the tightness is reduced. In fact, compared with the longitudinal wrinkles that are firmly pushed up in the thickness direction by the welded portion row along the up-down direction, the arched wrinkles 61 that are pushed up while bending in the left-right direction along the shape of the convex portion of the welded portion row Ra are likely to become soft to the touch.

[0088] In addition, as described above, the waist elastic member 23 is attached to the ventral waist portion 20 of the present embodiment without using an adhesive (or with a reduced amount of adhesive), and thus the flexibility is high. Therefore, the user who has the impression that the ventral waist portion 20 is soft by seeing the arched gathers 61 can more easily actually feel the flexibility of the ventral waist portion 20 obtained by not using an adhesive. Furthermore, by improving the flexibility of the ventral waist portion 20, the ventral waist portion 20 can easily fit along the body of the wearer.

[0089] in addition, Fig.10 This is a photograph of a natural state of an actually manufactured stretch sheet, in which an elastic member is arranged between a pair of sheets in order to explain the bow-shaped folds 61. Specifically, the length of the weld 50 in the left-right direction is set to 2.5 mm, the interval (D3) of the weld row Ra is set to 15 mm, the height (H) of the convex portion is set to 25.6 mm, and the length of the bottom edge of the convex portion (the length in the vertical direction from the weld 501 to the weld 502) is set to 50 mm.

[0090] In addition, as described above, at least a portion of the welded portion 503 located closest to the other side in the left-right direction of the third convex portion 53 only needs to be located inside the imaginary line La (the other side in the left-right direction). However, preferably, more than half of the welded portion 503 in the left-right direction may be located inside the imaginary line La (the other side in the left-right direction). More preferably, Figure 6 As shown in FIG. 1 , all the welded portions 503 may be located on the other side of the imaginary line La in the left-right direction.

[0091] By configuring in this way, the overlapping length of the first welding section row Ra1 and the second welding section row Ra2 in the left-right direction becomes longer. Therefore, when the ventral waistline 20 shrinks, the fifth convex portion 55 and the third convex portion 53 are easy to approach, and the arcuate folds 61 along the convex portions are easy to form. In addition, the so-called long overlapping length of the first welding section row Ra1 and the second welding section row Ra2 in the left-right direction can be said to be in the tendency that the height H of the convex portion of the welding section row Ra is high and the slope of the convex portion is large. Therefore, it is easy to form a larger arcuate fold 61, and the user is easy to have a soft impression of the ventral waistline 20.

[0092] In addition, if Figure 6As shown in FIG. 1 , the first weld region A1 includes a third weld row Ra3 located next to the second weld row Ra2 on one side in the left-right direction. The third weld row Ra3 includes a fourth convex portion 54 protruding toward the other side in the left-right direction. The fourth convex portion 54 has the same vertical position as the third convex portion 53 and is located between the first convex portion 51 and the second convex portion 52 in the vertical direction.

[0093] Furthermore, it is preferable that, in a state where the abdominal waistline portion 20 is extended in the left-right direction, the welded portion 504 at which the fourth convex portion 54 is located closest to the other side in the left-right direction (on the second welded portion row Ra2 side) is located further outward (on one side in the left-right direction) than the imaginary line La. In other words, it is preferable that the height H of the fifth convex portion 55 of the first welded portion row Ra1 is shorter than twice the length of the interval D3 in the left-right direction of the welded portion row Ra (H<2×D3).

[0094] That is, the first weld portion row Ra1 may overlap with the second weld portion row Ra2 adjacent in the horizontal direction, but may not overlap with the third weld portion row Ra3 adjacent to the next weld portion, or may overlap slightly (less than the horizontal length of the weld portion 50 ).

[0095] By configuring in this way, the interval D3 between the welded portion rows Ra in the horizontal direction is set larger, and the welded portion rows Ra can be prevented from being densely arranged in the horizontal direction. Therefore, the reduction in the horizontal flexibility of the abdominal waistline portion 20 due to the hardness of the welded portion 50 can be suppressed.

[0096] In addition, by appropriately increasing the interval D3 in the left-right direction of the welded portion row Ra, the area of ​​the sheet located between the welded portion rows Ra, that is, the area of ​​the sheet that bulges outward in the thickness direction when the abdominal waistline portion 20 contracts, can be ensured. Therefore, it is easy to form the arched pleats 61 having a length in the vertical direction. However, the present invention is not limited to the above-mentioned configuration, and the fourth convex portion 54 (welded portion 504) of the third welded portion row Ra3 may be located at a position further inside (on the other side in the left-right direction) than the imaginary line La.

[0097] In addition, it is preferable that the interval D3 between the first welded portion row Ra1 and the second welded portion row Ra2 in the left-right direction is 6 mm or more when the abdominal waistline portion 20 is stretched in the left-right direction. With such a configuration, it is possible to prevent the welded portion row Ra from being densely arranged in the left-right direction, compared with a case where the interval D3 between the welded portion rows Ra in the left-right direction is less than 6 mm. Therefore, it is possible to suppress a decrease in the flexibility of the abdominal waistline portion 20 due to the hardness of the welded portion 50.

[0098] In addition, although the interval D3 in the left-right direction of the welded portion row Ra is set to 6 mm or more and appropriately separated, the first welded portion row Ra1 and the second welded portion row Ra2 partially overlap in the left-right direction (so-called H>D3 relationship), and it can be said that the height H of the welded portion row Ra is high and the slope is large. Therefore, it is easy to form a larger arched fold 61, and the user is likely to have a soft impression of the ventral waistline portion 20. However, it is not limited to the above configuration, and the interval D3 may be less than 6 mm.

[0099] In addition, if Figure 6 As shown, the interval D3 refers to the left-right length of the left-right center of a weld 50 belonging to the first weld row Ra1 and the left-right center of a weld 50 belonging to the second weld row Ra2 which is the same as the weld 50 or closest to the weld 50 in the vertical direction.

[0100] In addition, the height H of the protrusion of the welding portion array Ra refers to the length in the left-right direction of the welding portion (for example, welding portion 501) at which the protrusion protruding on one side in the left-right direction (for example, the first protrusion 51) is located closest to one side and the welding portion (for example, welding portion 505) at which the protrusion adjacent to the protrusion in the up-down direction and protruding on the other side in the left-right direction (for example, the fifth protrusion 55) is located closest to the other side.

[0101] In addition, if Figure 7 As shown in FIG. 1 , in the first welded portion row Ra, the first convex portion 51 is located above the second convex portion 52 in the vertical direction. In addition, when the abdominal waistline portion 20 is extended in the horizontal direction, the line (other line) connecting the ends of the other side of the plurality of welded portions 50 constituting the second welded portion row Ra2 in the horizontal direction is set as the virtual line Lb. Figure 7 As shown in FIG. 1 , when the shape of the weld 50 is a rectangle or the like and the end portion of the weld 50 on the other side in the left-right direction is a side having a length in the vertical direction, a line connecting the centers of the side in the vertical direction is set as an imaginary line Lb. In addition, a point where the imaginary line Lb and the aforementioned imaginary line La intersect on the upper side in the vertical direction is set as a first intersection point P1, and a point where the imaginary line Lb and the imaginary line La intersect on the lower side in the vertical direction is set as a second intersection point P2.

[0102] At this time, it is preferable that the length W2 in the vertical direction from the end of the other side of the weld 501 in the horizontal direction, which is located closest to one side of the first convex portion 51 in the horizontal direction, to the first intersection P1 is greater than the length W3 in the vertical direction from the first intersection P1 to the second intersection P2 (W2>W3). In addition, when the end of the other side of the weld 501 in the horizontal direction is a side having a length in the vertical direction, the length from the center of the side in the vertical direction is set to W2.

[0103] The so-called relatively short length W3 in the vertical direction from the first intersection point P1 to the second intersection point P2 refers to the tendency of the slope of the third convex portion 53 to become larger. Therefore, it is easy to form an arcuate wrinkle 61 with a large slope along the convex portion of the welding portion row Ra, and the arcuate wrinkle 61 is easy to be recognized by the user. In addition, it can also be said that the third convex portion 53 does not enter the inner side (the other side of the left-right direction) of the imaginary line La too much. Therefore, it is possible to suppress the welding portion row Ra from being densely arranged in the left-right direction, and the softness of the abdominal waistline 20 can be ensured. In addition, when the abdominal waistline 20 shrinks, the area of ​​the sheet bulging outward in the thickness direction can be ensured, and the arcuate wrinkle 61 is easy to form. However, it is not limited to the above-mentioned structure, and the length W2 can also be less than the length W3.

[0104] In addition, since the welded portion row Ra has a convex portion, it is easy to form the arched folds 61 along the convex portion. However, if the convex portion of the welded portion row Ra is formed by a welded portion continuous in the vertical direction, the rigidity of the abdominal waistline portion 20 in the vertical direction will increase due to the hardness of the welded portion. Figure 6 As shown, the welded portions 50 are arranged at intervals in the vertical direction, and the positions of the welded portions 50 adjacent to each other in the vertical direction are shifted in the horizontal direction, so that the welded portion row Ra has a convex shape.

[0105] Specifically, if Figure 6 As shown in the figure, the lower weld 501 of the two welds 50 sandwiching a waist elastic member 231 (first elastic member) in the vertical direction is discontinuous with the upper weld 50u of the two welds 50 sandwiching a waist elastic member 232 (second elastic member) located next to the lower side of the waist elastic member 231 in the vertical direction. With such a configuration, the rigidity of the abdominal waist portion 20 in the vertical direction can be prevented from being increased due to the hardness of the weld 50, and the abdominal waist portion 20 can be easily bent in the vertical direction, thereby improving the flexibility of the abdominal waist portion 20 in the vertical direction.

[0106] In addition, in the ventral waistline portion 20, a plurality of waist elastic members 23 are arranged in the vertical direction, but the number or arrangement interval is not particularly limited. However, it is preferred that at least one waist elastic member 23 be provided between two convex portions that protrude toward the same side in the horizontal direction and are adjacent in the vertical direction in the welded portion array Ra, for example, between the welded portion 501 of the first convex portion 51 and the welded portion 502 of the second convex portion 52. With such a configuration, when the ventral waistline portion 20 contracts, between the two convex portions adjacent in the vertical direction (for example, the first convex portion 51 and the second convex portion 52), the welded portion array Ra adjacent in the horizontal direction is easy to approach (the fifth convex portion 55 and the third convex portion 53 are easy to approach), and the arch-shaped pleats 61 are easy to form.

[0107] In the welded portion row Ra included in the first welded area A1, the convex portions that are convex portions of the same shape (same height or slope), convex portions that are convex toward one side in the left-right direction, and convex portions that are convex toward the other side in the left-right direction are alternately arranged in the up-down direction. Therefore, a part of the convex portions included in the welded portion row Ra overlaps with the welded portion row Ra adjacent in the left-right direction in the left-right direction.

[0108] For example, Figure 7 As shown in the figure, the second protrusion 52 is located on one side in the left-right direction compared to the imaginary line Ld extending downward along the vertical direction from the end of the welding portion 503 on one side in the left-right direction at the position closest to the other side in the left-right direction at the third protrusion 53. Therefore, it is easy to form an arcuate fold 61 (the fold 61 along the second protrusion 52) with the opposite direction below the arcuate fold 61 formed between the fifth protrusion 55 and the third protrusion.

[0109] Thus, it is preferred that the welded portion array Ra has a shape that meanders in the left-right direction, such as Fig. 9 or Fig.10 As shown in the figure, the arched pleats 61 protruding toward one side and the other side in the left-right direction are alternately formed in the vertical direction. With such a configuration, the pleats 61 formed in the ventral waistline portion 20 are divided in the vertical direction by switching the directions of the arched pleats 61. Therefore, the ventral waistline portion 20 is easily bent in the vertical direction, and the flexibility of the ventral waistline portion 20 can be improved.

[0110] However, the shape of the welded portion row Ra is not limited to the above configuration. For example, only a portion of the welded portion row Ra may have a convex portion, and the other portion may be a straight line or may have a convex portion of a different shape (height or slope).

[0111] In the first weld region A1 of the present embodiment, weld columns Ra having the same arrangement pattern of the welds 50 are arranged at equal intervals D3 in the left-right direction. Therefore, in the first weld region A1, the first weld columns Ra1 having the first convex portions 51 and the second convex portions 52 and the second weld columns Ra2 having the third convex portions 53 are alternately arranged in the left-right direction. That is, the first weld region A1 has a plurality of combinations of the first weld columns Ra1 and the second weld columns Ra2 adjacent to each other in the left-right direction.

[0112] Therefore, in the first weld region A1, in the plurality of groups of welded portion rows Ra adjacent to each other in the left-right direction, the aforementioned relationship between the first convex portion 51 to the third convex portion 53 is established. Therefore, in the first weld region A1, a plurality of arched folds 61 are easily formed in the left-right direction, and the user is likely to have a soft impression of the ventral waistline portion 20. In addition, the aforementioned third welded portion row Ra3 is also equivalent to the first welded portion row Ra1, and the fourth convex portion 54 of the third welded portion row Ra3 corresponds to the fifth convex portion 55 of the first welded portion row Ra1.

[0113] More preferably, if Figure 4 As shown in FIG. 1 , the first welded area A1 may overlap at least a portion of the side joint SS on one side in the left-right direction, and overlap at least a portion of the side joint SS on the other side in the left-right direction. Figure 4 In the embodiment, the welded portion row Ra is formed to extend to the outside of the side joint portion SS in the left-right direction.

[0114] In this case, the arched gathers 61 are easily formed over a wide range in the left-right direction of the abdominal waistline portion 20. Therefore, the arched gathers 61 are easily recognized by the user, and the user is likely to have an impression that the abdominal waistline portion 20 is soft.

[0115] In addition, it is preferred that, as in the first weld region A1 of the present embodiment, weld columns Ra having the same arrangement pattern of the weld 50 are arranged at equal intervals D3 in the left-right direction. By configuring in this way, it is easy to form more arch-shaped wrinkles 61. In addition, the same arrangement pattern or equal intervals D3 refer to the equivalence in design, and also include the case where some deviations occur due to manufacturing errors. However, it is not limited to the above configuration. The first weld region A1 only needs to have at least one combination of the first weld column Ra1 and the second weld column Ra2, and preferably has a plurality of combinations of the first weld column Ra1 and the second weld column Ra2. The first weld region A1 may also have weld columns of different shapes, or the intervals between weld columns are different. In this case, the range from the first weld column Ra1 or the second weld column Ra2 located closest to one side in the left-right direction to the first weld column Ra1 or the second weld column Ra2 located closest to the other side is set as the first weld region A1.

[0116] In addition, when the skin side sheet 21 and the non-skin side sheet 22 (a pair of sheets) constituting the ventral waistline 20 (stretchable sheet 40) are non-woven fabrics, embossing is sometimes applied to the non-woven fabric. In this case, the shape of one pattern of embossing is preferably a shape whose length in the left-right direction is less than the length in the up-down direction (e.g., a dot or square, a rhombus, an ellipse or a rectangle long in the up-down direction, etc.). By forming it in this way, when the ventral waistline 20 shrinks in the left-right direction, the sheet between the welded portion rows Ra bulges outward in the thickness direction, and it is easy to form a bow-shaped fold 61.

[0117] (Regarding the Second Welding Area A2)

[0118] Next, the second fusion region A2 will be described. Figure 4 As shown, the second welded area A2 is located above the first welded area A1 and is positioned at a predetermined width at the upper end of the abdominal waistline 20. The upper end of the waistline is the upper area when the waistline is divided into two in the vertical direction, and is preferably the uppermost area when the waistline is divided into three in the vertical direction. Figure 4 In the example, the second welded area A2 is positioned in a region with a predetermined width W1 (e.g., about 30 mm) from the upper end 20a of the abdominal waistline portion 20, but the present invention is not limited thereto. For example, the second welded area A2 may be positioned downwardly away from the upper end 20a of the abdominal waistline portion 20.

[0119] Similar to the welded portion row Ra included in the first welded region A1, the welded portion row Rb (fourth welded portion row) included in the second welded region A2 has convex portions that alternately convex toward one side and the other side in the left-right direction, and forms a shape that meanders in the left-right direction. However, they may be arranged in the left-right direction at a spacing D4 (<D3) that is smaller than the spacing D3 in the left-right direction of the welded portion row Ra included in the first welded region A1.

[0120] Furthermore, it is preferable that any of the following is true when the abdominal waistline portion 20 is stretched in the left-right direction.

[0121] First, if Fig. 8A As shown, the overlapping length of the welded portion rows Rb adjacent to each other in the horizontal direction may be less than the horizontal length h of the welded portion 50 (eg, welded portion 506 or welded portion 507 ) in the welded portion row Rb, which has the most protruding convex portion.

[0122] That is, for the convex parts 56 and 57 that are adjacent to each other in the vertical direction and protrude toward one side in the left-right direction and that are included in the welded part row Rb on the other side in the left-right direction, the line connecting the ends of the welded parts 506 and 507 located closest to one side in the left-right direction on the other side in the left-right direction is set as the virtual line Le. At this time, a part of the convex part 58 that is included in the welded part row Rb located next to one side in the left-right direction and protrudes toward the other side in the left-right direction overlaps with the convex parts 56 and 57, but may be located outside the virtual line Le (on one side in the left-right direction).

[0123] Or, if Figure 8B As shown, the welded portion rows Rb adjacent to each other in the left-right direction do not need to overlap in the left-right direction.

[0124] That is, the left-right position of the end portion on one side of the left-right direction of the weld portion row Rb (convex portions 56, 57) located on the other side in the left-right direction may coincide with the end portion on the other side in the left-right direction of the weld portion row Rb (convex portion 58) located on one side in the left-right direction, or may be separated in the left-right direction.

[0125] In the above case, the following tendency is that the winding amount of the convex parts 56 to 58 of the welded part row Rb becomes smaller and the slope of the convex parts 56 to 58 becomes smaller. Fig. 9 As shown, the wrinkles 62 formed between the welded portion rows Rb are wrinkles with a smaller inclination relative to the vertical direction (wrinkles close to longitudinal wrinkles) than the arched wrinkles 61 formed in the first welded region A1. In the second welded region A2, such wrinkles 62 are formed at smaller intervals than the wrinkles 61 formed in the first welded region A1.

[0126] Therefore, the user who sees the second welded area A2 is likely to have the impression that the fit is higher than that of the first welded area A1. By providing such a second welded area A2 at the upper end of the ventral waistline portion 20, the user is likely to have the impression that the upper part of the waistline (the second welded area A2) fits firmly and is unlikely to fall off, and the other parts (the first welded area A1) fit softly and have a good wearing feeling.

[0127] In addition, by forming the pleats 62 close to the longitudinal pleats in the second fusion region A2, the rigidity of the second fusion region A2 in the vertical direction is improved. Therefore, the upper end of the ventral waistline portion 20 can be prevented from rolling up due to the fatness of the wearer's abdomen, etc. However, the present invention is not limited to the above-mentioned structure, and the ventral waistline portion 20 (elastic sheet 40) may not have the second fusion region A2.

[0128] (other)

[0129] In the above-mentioned embodiment, the stretch sheet 40 is provided in the ventral waist portion 20. That is, the stretch sheet 40 is provided in the ventral waist portion 20 in such a manner that the left-right direction of the stretch sheet 40 (the direction along which the elastic member extends) coincides with the left-right direction of the panty-type diaper 1, and the up-down direction of the stretch sheet 40 (the direction orthogonal to the elastic member) coincides with the up-down direction of the panty-type diaper 1. In addition, in the above-mentioned embodiment, both the ventral waist portion 20 and the dorsal waist portion 30 are formed by the stretch sheet 40, but only one of the waist portions may be formed by the stretch sheet 40. In addition, like the dorsal waist portion 30, an extension portion 30E is provided at a position lower than the side joint portion SS, which is aligned with the dorsal waist portion 30. Figure 2 However, when the extension portion 30E is also provided with an elastic member along the left-right direction, the extension portion 30E may be constituted by the stretch sheet 40 .

[0130] In addition, the stretch sheet 40 is not limited to being applied to the waist circumference 20, 30 of the underpants-type diaper 1, and can also be applied to other parts of the diaper 1, such as the stretchable part of the leg circumference. In addition, the stretch sheet 40 can also be applied to absorbent articles other than the underpants-type diaper 1 (such as belt-type diapers or urine-absorbing pads, sanitary products, etc.), and can also be applied to products other than absorbent articles (such as cleaning components or masks, etc.).

[0131] The above embodiments are intended to facilitate understanding of the present invention and are not intended to be limiting of the present invention. The present invention may be modified and improved without departing from its concept, and the present invention also includes equivalent configurations.

[0132] Description of Reference Numerals

[0133] 1 Diapers (underwear-type absorbent articles),

[0134] 10 absorbent body, 11 absorbent core, 12 top sheet,

[0135] 13 bottom sheet, 14 outer sheet, 15 leg elastic member,

[0136] 16 Leakage-proof wall elastic member,

[0137] 20 ventral waist circumference (waist circumference),

[0138] 21 Skin side sheet (sheet), 22 Non-skin side sheet (sheet),

[0139] 23 waist elastic member (elastic member),

[0140] 30 back waist (waist), 30E extension,

[0141] 31 skin side sheet (sheet), 32 non-skin side sheet (sheet),

[0142] 33 waist elastic member (elastic member),

[0143] 40 stretchable sheets,

[0144] SS side joint,

[0145] 50 weld, 50S weld pair,

[0146] 51 1st convex part, 52 2nd convex part, 53 3rd convex part,

[0147] La imaginary line (line), Lb imaginary line (other line),

[0148] P1 is the first intersection, P2 is the second intersection,

[0149] 61 pleats, 62 pleats.

Claims

1. A stretchable sheet having an up-down direction and a left-right direction intersecting each other, A plurality of elastic members that can stretch in the left-right direction are arranged at intervals in the up-down direction between a pair of sheets joined by a plurality of welded portions, characterized in that: Each of the elastic members is clamped between the two welded portions adjacent to each other in the up-down direction in a state of being contracted in the left-right direction, so that the position of each elastic member in the left-right direction relative to the pair of sheets is restricted. The stretch sheet has a plurality of welded portion rows in which a plurality of the welded portions are arranged in the vertical direction. The plurality of welded portion rows include: a first welded portion row; and a second welded portion row located next to the first welded portion row on one side in the left-right direction. The first welded portion row includes a first convex portion and a second convex portion that protrude toward the one side in the left-right direction and are adjacent to each other in the up-down direction. The second welded portion row has a third protrusion protruding toward the other side in the left-right direction. In the state extended along the left-right direction, compared with the line connecting the ends of the welding portion on the other side of the left-right direction where the first protrusion and the second protrusion are respectively located at the positions closest to the one side in the left-right direction, at least a portion of the welding portion where the third protrusion is located at the position closest to the other side in the left-right direction is located on the other side of the left-right direction.

2. The stretchable sheet according to claim 1, wherein The plurality of welded portion rows include a third welded portion row located next to the second welded portion row on the one side in the left-right direction. The third welded portion row has a fourth protrusion protruding toward the other side in the left-right direction. In a state extended in the left-right direction, the welded portion is located on the one side in the left-right direction when the fourth protrusion is located closest to the other side in the left-right direction relative to the line.

3. The stretchable sheet according to claim 1 or 2, wherein When extended in the left-right direction, more than half of the weld portion in the left-right direction where the third protrusion is located closest to the other side in the left-right direction relative to the line is located on the other side in the left-right direction.

4. The stretchable sheet according to claim 3, wherein In a state extended in the left-right direction, all of the welded portions where the third protrusion is located closest to the other side in the left-right direction relative to the line are located on the other side in the left-right direction.

5. The stretchable sheet according to claim 1 or 2, wherein In the state of being extended in the left-right direction, a distance between the first weld portion row and the second weld portion row in the left-right direction is 6 mm or more.

6. The stretchable sheet according to claim 1 or 2, wherein: The first protrusion is located above the second protrusion in the up-down direction. In the state stretched in the left-right direction, the stretchable sheet has: another line connecting the ends on the other side of the left-right direction of the plurality of welded portions constituting the second welded portion row; a first intersection point where the other line intersects the line at the upper side; and a second intersection point where the other line intersects the line at the lower side of the up-down direction, The length in the up-down direction from the end of the other side of the fusion portion located closest to the one side in the up-down direction to the first intersection is greater than the length in the up-down direction from the first intersection to the second intersection.

7. The stretchable sheet according to claim 1 or 2, wherein The plurality of elastic members include: a first elastic member; and a second elastic member located next to the lower side of the first elastic member in the up-down direction. The lower weld portion of the two weld portions sandwiching the first elastic member in the up-down direction is discontinuous with the upper weld portion of the two weld portions sandwiching the second elastic member in the up-down direction.

8. A pants-type absorbent article comprising the stretch sheet according to claim 1 or 2, characterized in that: The above-mentioned underwear type absorbent article has an up-down direction and a left-right direction intersecting each other, and has an absorbent body and a pair of waist parts. The elastic sheet is provided on at least one of the pair of waist portions. The up-down direction of the stretch sheet is along the up-down direction of the underwear-type absorbent article. The left-right direction of the stretch sheet is along the left-right direction of the pull-on absorbent article.

9. The underpants-type absorbent article according to claim 8, wherein: The stretch sheet includes a first fusion region having a combination of a plurality of first fusion portion rows and a plurality of second fusion portion rows adjacent to each other in the left-right direction.

10. The underpants-type absorbent article according to claim 9, wherein: The pair of waist parts are joined by a pair of side joint parts at both sides in the left-right direction. The first weld region overlaps at least a portion of the side joint portion on the one side in the left-right direction, and overlaps at least a portion of the side joint portion on the other side in the left-right direction.

11. The underpants-type absorbent article according to claim 9 or 10, characterized in that: The stretch sheet has a second welded region. In the second weld region, a plurality of fourth weld portions are arranged in the left-right direction, the fourth weld portion rows having convex portions alternately convex toward the one side and the other side in the left-right direction, In a state where the stretch sheet is stretched in the left-right direction, The fourth welded portion rows adjacent to each other in the left-right direction do not overlap in the left-right direction, or the overlapping length in the left-right direction is less than the length in the left-right direction of the welded portion at the position where the protrusion is located on the most protruding side in the left-right direction. The interval between the fourth welded portion row in the left-right direction is smaller than the interval between the first welded portion row and the second welded portion row in the left-right direction. The second welded region is located at the upper end of the waist portion with a predetermined width. The first fusion region is located below the second fusion region.

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