WO2023127399A1

WO2023127399A1 - Underpants-type absorbent article

Info

Publication number: WO2023127399A1
Application number: PCT/JP2022/044566
Authority: WO
Inventors: 京子石橋; 宏子川口
Original assignee: 花王株式会社
Priority date: 2021-12-27
Filing date: 2022-12-02
Publication date: 2023-07-06
Also published as: JP2023096859A; CN118251197A; JP7404329B2

Abstract

This underpants-type absorbent article comprises an absorbent main body, an exterior body, and a pair of side joining parts. The pair of side joining parts join an abdomen-side region and a back-side region of the exterior body at a horizontal-direction lateral edge orthogonal to the vertical direction. The side joining parts have a waist-end region and a leg-end region, and a plurality of seal rows formed by a plurality of seal parts arrayed separated along the vertical direction, the seal rows being separated from each other in the horizontal direction and disposed in at least one end region. The seal parts positioned on the inner side in the horizontal direction have a lower seal strength than the seal parts positioned on the outer side in the horizontal direction.

Description

Pants-type absorbent article

The present invention relates to pants-type absorbent articles such as disposable diapers.

Pants-type absorbent articles generally include an absorbent main body, an outer body, and side joints (side seal parts) that join the abdominal outer body and the dorsal outer body at side ends. there is The waist opening and the leg opening of the pants-type absorbent article are formed by joining the outer covering body on the abdomen side and the outer covering body on the back side by the side joints.

Patent Document 1 discloses a pants-type disposable diaper provided with a pair of side seal portions having a main joint region and a sub-joint region formed by a plurality of embossed rows spaced apart in the left-right direction. there is The main joining region joins the front body and the back body. From the viewpoint of preventing the front body and the back body from being released, the secondary joint area is positioned laterally outside the main joint area and is formed so that the joint strength is weaker than that of the main joint area. .

JP 2014-233624 A

The pants-type absorbent article according to one aspect of the present invention has a longitudinal direction extending from the wearer's abdomen through the crotch to the dorsal side, and a lateral direction perpendicular to the longitudinal direction and corresponding to the lateral direction of the wearer. and comprising an absorbent body, an outer body, and a pair of side joints.
The outer body is arranged on the non-skin-facing side of the absorbent main body, includes a ventral region and a dorsal region located on both sides in the longitudinal direction, and is constructed by laminating a plurality of thermoplastic sheets.
The pair of side joints joins the ventral region and the dorsal region of the exterior body at the side edges in the horizontal direction.
The pair of side joints are
an end region within 25 mm in the longitudinal direction from the waist end, which is the end on the waist side in the longitudinal direction;
and a leg end region within 25 mm in the longitudinal direction from the leg end, which is the leg-side end in the longitudinal direction.
At least one of the pair of side joints,
a plurality of seal rows arranged in at least one of the waist end region and the leg end region along the transverse direction, each of which is composed of a plurality of seal portions spaced apart and aligned along the longitudinal direction; have.
Of the two laterally adjacent seal portions belonging to different seal rows, the laterally inner seal portion has a lower seal strength than the laterally outer seal portion.

1 is a schematic perspective view showing a pants-type absorbent article according to a first embodiment of the present invention; FIG. FIG. 4 is a schematic plan view showing the side of the underpants-type absorbent article facing the skin, showing a mode in which the underpants-type absorbent article is unfolded and the elastic members of each part are stretched and spread flatly. FIG. . FIG. 4 is a schematic plan view showing side joints of the pants-type absorbent article. It is a figure which shows typically the microscope image which expanded the cross section of the said side joint part about 300 times. FIG. 4 is a diagram showing an example of a graph obtained by measuring the seal strength in the waist end region of the side joint, where the vertical axis is the seal strength (N) and the horizontal axis is the distance from the peel start point on the inner side in the horizontal direction. indicates It is a diagram schematically showing a microscopic image of the seal portion of the side joint portion enlarged about 500 times, (A) is the fiber of the seal portion belonging to the laterally inner seal row, (B) is the laterally outer The fibers of the seal part belonging to the seal row are shown. 4 is an enlarged view of a main part of FIG. 3; FIG. FIG. 4 is a schematic plan view showing a side joint portion of the pants-type absorbent article, and a diagram showing the positional relationship between the seal portion and the elastic member. FIG. 4 is a schematic cross-sectional view of the side joint portion, showing a mode in which a ventral region and a dorsal region are separated. (A) and (B) are schematic plan views each showing a side joint according to a modification of the embodiment. (A) and (B) are schematic plan views each showing a side joint according to a modification of the embodiment. FIG. 4 is a schematic plan view showing side joints of a pants-type absorbent article according to a second embodiment of the present invention; FIG. 10 is a schematic cross-sectional view of a side joint portion of a pants-type absorbent article according to a third embodiment of the present invention, showing a state in which an abdominal area and a dorsal area are separated. FIG. 10 is a schematic cross-sectional view of a side joint portion of a pants-type absorbent article according to a fourth embodiment of the present invention, showing a state in which an abdominal area and a dorsal area are separated. FIG. 10 is a schematic cross-sectional view of a side joint portion of a pants-type absorbent article according to a fifth embodiment of the present invention, showing a state in which a ventral region and a dorsal region are separated. FIG. 11 is a schematic plan view showing side joints of a pants-type absorbent article according to a sixth embodiment of the present invention; It is a typical top view which shows the side joint part which concerns on the modification of the said embodiment.

Detailed description of the invention

After wearing the pants-type absorbent article, the side joints are sometimes torn and discarded from the viewpoint of hygiene. Therefore, the side joints are required to have the function of not being peeled off during the wearing operation (when putting on the underpants-type absorbent article) and during wearing, and being able to be easily torn off at the time of disposal.
On the other hand, the underpants-type disposable diaper described in Patent Document 1 required a strong force to tear the side seal portions, and the side seal portions could not be easily torn.

The present invention relates to the provision of a pants-type absorbent article that can achieve both prevention of peeling during wearing and wearing, and ease of tearing during disposal.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<First embodiment>
[Overall configuration of underpants-type disposable diaper]
1 and 2 show an underpants-type disposable diaper 1 as an underpants-type absorbent article according to a first embodiment of the present invention. The pants-type disposable diaper 1 is hereinafter referred to as the diaper 1 .
As shown in FIG. 1, the diaper 1 has a waist opening 1W and a pair of leg openings 1L, and is worn around the wearer's waist and crotch when worn. The waist opening 1W has a waist opening end Wa. The diaper 1 has a longitudinal direction X and a transverse direction Y. As shown in FIG. The longitudinal direction X extends from the abdomen of the wearer through the crotch to the dorsal side. The lateral direction Y is orthogonal to the longitudinal direction X and corresponds to the lateral direction of the wearer. Further, as shown in FIG. 2 and the like, a direction perpendicular to the longitudinal direction X and the lateral direction Y of the diaper 1 is defined as a thickness direction Z. As shown in FIG.
In this specification, the "waist side" means the side in the longitudinal direction X near the waist opening end Wa of the waist opening 1W, and the "leg side" means the side in the longitudinal direction X from the waist opening end Wa. It means the far away side.
In this specification, the term “lateral direction Y inner side” means the side in the lateral direction Y that approaches the vertical center line CL that bisects the pants-type absorbent article (diaper 1) in the lateral direction Y. "Direction Y outside" means the side away from the longitudinal center line CL.
In this specification, regarding the thickness direction Z, the side close to the wearer's skin when wearing the pants-type absorbent article (diaper 1) is sometimes called the skin side, and the side close to the clothes is sometimes called the non-skin side. Further, the "skin-facing surface" of the pants-type absorbent article (diaper 1) or its constituent members means the surface relatively close to the wearer's skin. The "non-skin facing surface" of the pants-type absorbent article (diaper 1) or its constituent members means the surface relatively far from the wearer's skin.
Further, in this specification, numerical values such as dimensions and areas of each portion are measured in a natural state in which the elastic member of each portion is not stretched unless otherwise specified.

When the wearer puts on the diaper 1, the wearer first puts the legs through the pair of leg openings 1L, pulls up the diaper 1 toward the body, and places the diaper 1 around the wearer's waist and crotch. In this specification, this series of actions is referred to as a "wearing action". The action of putting on the diaper 1 may be performed not by the wearer of the diaper 1 but by a caregiver.
In addition, in this specification, the state in which the diaper 1 is arranged at the wearing position that is normally assumed to be worn by the wearer is referred to as "when worn".

As shown in FIGS. 1 and 2, the diaper 1 includes an absorbent main body 4 and an exterior body 5 arranged on the non-skin facing side of the absorbent main body 4 .
In addition, FIG. 2 shows a form in which the diaper 1 is unfolded, the elastic members of each part are stretched, and the diaper 1 is flattened so as to achieve the design dimensions in which the influence of the elastic members is completely eliminated. This mode is also referred to as the “deployed and stretched mode” of the diaper 1 . Unfolding the diaper 1 means separating the ventral region 5a and the dorsal region 5b of the side joints 8, which will be described later.

The absorbent main body 4 is fixed to the skin-facing surface side of the exterior body 5 . The absorbent main body 4 has at least an absorbent body 40, and may further have a topsheet 2, a backsheet (not shown), and the like. For example, the absorbent main body 4 has a configuration in which a back sheet, an absorbent body 40 and a top sheet 2 are laminated in the thickness direction Z. As shown in FIG. The absorbent body 40 includes a liquid-retaining absorbent core, and may further include a core wrap sheet covering the absorbent core.
Materials used in the respective components (backsheet, absorbent body 40, topsheet 2, etc.) included in the absorbent main body 4 may be those used in the relevant technical field without particular limitations.

The outer body 5 includes multiple thermoplastic sheets 50 . The exterior body 5 is configured as a laminate of a plurality of thermoplastic sheets 50, for example.
The thermoplastic sheet 50 is a sheet material mainly made of thermoplastic resin. The thermoplastic sheet 50 preferably contains 90% by mass or more of thermoplastic resin, more preferably 100% by mass of thermoplastic resin.
Examples of thermoplastic resins include polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate; polyamides such as nylon 6 and nylon 66; These 1 types can be used individually or in combination of 2 or more types. The thermoplastic fibers may be short fibers or long fibers. As thermoplastic fibers, core-sheath type or side-by-side type composite fibers, split fibers, modified cross-section fibers, heat-shrinkable fibers, and the like can also be used.

The outer body 5 has at least a ventral region 5a arranged on the ventral side of the wearer and a dorsal region 5b arranged on the dorsal side of the wearer. The outer body 5 of this embodiment further includes a crotch region 5c located between the abdominal region 5a and the dorsal region 5b and arranged in the wearer's crotch region. In this example, the ventral region 5a, the crotch region 5c, and the dorsal region 5b are arranged along the longitudinal direction X. As shown in FIG. Further, the outer body 5 has a shape constricted inward in the lateral direction Y in the crotch region 5c. Thereby, a leg opening 1L (see FIG. 1) is formed along the wearer's leg loop.
It is preferable that the outer edge of the exterior body 5 is configured line-symmetrically (left-right symmetrically) with respect to the longitudinal center line CL.

Furthermore, the exterior body 5 has a pair of side joints 8 where a side edge 5d in the lateral direction Y of the ventral region 5a and a side edge 5e in the lateral direction Y of the dorsal region 5b are respectively joined. . The right side joint portion 8 has a structure in which a right side edge portion 5d of the ventral region 5a and a right side edge portion 5e of the dorsal region 5b are overlapped in the thickness direction Z and joined. The left side joint portion 8 has a structure in which a left side edge portion 5d of the ventral region 5a and a left side edge portion 5e of the dorsal region 5b are overlapped in the thickness direction Z and joined.
By the pair of side joints 8, the abdominal area 5a and the dorsal area 5b form a tubular shape along the waist of the wearer, forming a waist opening 1W and leg openings 1L of the diaper 1. As shown in FIG.
The side joints 8 are preferably joined by heat sealing, ultrasonic sealing, or the like, as will be described later in detail.

[Structure of side joint]
It is preferable that the side joints 8 maintain the jointed state without peeling off the ventral region 5a and the dorsal region 5b during the wearing operation and wearing.
On the other hand, when changing the diaper 1 after wearing it, from the viewpoint of hygienically disposing of the excrement adhering to the diaper 1, a caregiver or the like should separate the ventral region 5a and the dorsal region 5b of the side joints 8 from each other. are separated and the diaper 1 is unfolded and then discarded.
In this way, it is preferable that the side joints 8 have such a structure that they can be prevented from being peeled off during the wearing operation and wearing, and can be easily torn at the time of disposal.
In this specification, unintentional separation of the ventral region 5a and the dorsal region 5b of the side joints 8 when the diaper 1 is put on and worn is expressed as "peeled off". On the other hand, when discarding the diaper 1, the operation of intentionally separating the ventral region 5a and the dorsal region 5b of the side joints 8 by applying an external force to the side joints 8 and/or their surroundings is referred to as " Tear apart.”
Also, the subject who tears the side joints 8 when discarding the diaper 1 is expressed as a "disposer".

In the present embodiment, it is preferable that the pair of side joints 8 are configured substantially line-symmetrically with respect to the longitudinal center line CL, for example, and have the same configuration. The configuration of one side joint portion 8 will be described in detail below.

As shown in FIG. 2, the side joints 8 are a waist end region 8c within 25 mm in the longitudinal direction X from a waist end 8a, which is the end on the waist side, and an end on the leg side in the longitudinal direction X. and a leg end region 8d within 25 mm in the longitudinal direction X from the leg end 8b.
The waist end portion 8a and the leg end portion 8b constitute both end portions of the side joint portion 8 in the longitudinal direction X. As shown in FIG.
The side joint portion 8 has a configuration extending in the longitudinal direction X from the waist end portion 8a to the leg end portion 8b as a whole.
In addition, in the side joint portion 8, the longitudinal direction X end side means the side approaching the waist end portion 8a or the leg end portion 8b, and the longitudinal direction X central side means the waist end portion 8a or the leg end portion 8b. means the side away from

The side joint portion 8 further has a plurality of seal portions S. The seal portion S is a portion where the thermoplastic sheets 50 of both the ventral region 5a and the dorsal region 5b are fused and joined. The sealed portion S is bonded by, for example, pressurizing means and/or heating means, and specifically by heat sealing, ultrasonic sealing, or the like.
As shown in FIG. 4, when the XZ cross section (the cut surface in the longitudinal direction X) of the side joint portion 8 is enlarged, the sealing portion S is thicker than the surroundings due to the fusion of the fibers 55 of the thermoplastic sheet 50. is observed as a thinned portion.

As shown in FIG. 3, the plurality of seal portions S are spaced apart in the vertical direction X. As shown in FIG. This can prevent the entire side joint portion 8 from peeling off along the vertical direction X when one seal portion S is peeled off.
The planar shape of the seal portion S is not particularly limited, and may be a shape selected from a rectangular shape, other polygonal shapes, a circular shape, an elliptical shape, shapes similar thereto, and other shapes.
As shown in FIG. 3, the planar shape of the seal portions S is preferably a rectangular shape from the viewpoint of securing a sufficient area for each seal portion S while leaving a space therebetween.

Here, according to the findings of the present inventors, at the start of the tearing operation of the side joints 8, the fingers of the disposal person are separated from the waist end 8a or the leg end 8b by about 25 mm to 30 mm in the longitudinal direction X. It is likely to be arranged on both the left and right sides (abdominal side and dorsal side) of the side joint portion 8 . For example, when the wearer is standing, the disposer's fingers are likely to be placed on the waist side, and when the wearer is lying down, the disposer's fingers are likely to be placed on the leg side.
Therefore, in the side joints 8, the region to which the external force for tearing (also referred to as "tearing force") is particularly likely to be applied is the waist end within 25 mm in the longitudinal direction X from the waist end 8a and the leg end 8b. Region 8c and leg end region 8d are defined. From the viewpoint of facilitating tearing during disposal while preventing tearing during wearing and wearing, the arrangement and sealing strength of the seal portion S in the waist end region 8c and/or the leg end region 8d are adjusted. Configure as follows.
Note that FIG. 3 shows an example in which the region where the seal portion S has a characteristic arrangement and seal strength is the waist end region 8c.

As shown in FIG. 3, at least one of the side joints 8 is each composed of a plurality of seals S spaced apart in the longitudinal direction X and aligned in the transverse direction Y in the waist end region 8c. has a plurality of seal rows SL.
"A plurality of seal portions S are aligned along the longitudinal direction X with a space therebetween" means that a plurality of seal portions S spaced apart in the longitudinal direction X are arranged side by side on a straight line extending in the longitudinal direction X. means Specifically, in one seal row SL, it is preferable that the deviation of the straight line that bisects each seal portion S in the lateral direction Y is within 50% of the maximum dimension of the seal portion S in the lateral direction Y.

“The seal rows SL are arranged along the lateral direction Y” means that a plurality of seal rows are aligned in the lateral direction Y, and the seal portions S belonging to the seal rows SL adjacent to each other in the lateral direction Y are arranged apart from each other. means to be
In the present embodiment, at least a portion of the plurality of seal rows SL may be arranged in the waist end region 8c, and may extend in the longitudinal direction X from the waist end region 8c. In the example shown in FIG. 3 , a plurality of seal rows SL are arranged over the longitudinal direction X of the side joint portion 8 .

In the example shown in FIG. 3, three seal rows SL are arranged in the waist end region 8c. These seal rows SL are also referred to as a first seal row SL1, a second seal row SL2, and a third seal row SL3 from the inner side to the outer side in the lateral direction Y. In the following description, when there is no need to distinguish these seal rows SL, they are simply referred to as seal rows SL.
Note that the number of seal rows SL in the waist end region 8c is not limited to three. For example, the number of seal rows SL in the waist end region 8c is two or more, preferably three or more and seven or less.

In the above configuration, the seal portions S belonging to each seal line SL are spaced apart in the vertical direction X and the horizontal direction Y. As a result, when one seal portion S is peeled off during wearing and wearing operation, the influence thereof is less likely to propagate to the other seal portions S. Therefore, it is possible to effectively prevent the peeling of the side joints 8 during the wearing operation and wearing.

On the other hand, at the start of the tearing action, a tearing force F having both longitudinal direction X central side and lateral direction Y outer components is applied from the inside of the waist end region 8c and/or the leg end region 8d. As shown in FIG. 3, this tearing force F is an oblique outward force that is inclined by about 45° with respect to the longitudinal direction X and the lateral direction Y. As shown in FIG. Therefore, in the side joint portion 8, the seal portion S extends from the seal portion S on the end side in the longitudinal direction X of the first seal row SL1 toward the center in the longitudinal direction X and from the inner side to the outer side in the lateral direction Y. torn apart in order.
In the waist end region 8c and/or the leg end region 8d in which a plurality of seals S are arranged in the longitudinal direction X and the lateral direction Y, before tearing of the seals S in the inner seal row SL in the lateral direction Y is completed, The tearing of the seal portion S of the diagonally adjacent outer seal row SL often begins. At the side joint portion 8 , the two diagonally adjacent seal portions S are torn almost simultaneously at close positions, which may locally apply an excessive load to the exterior body 5 . As a result, at the side joint portion 8, the exterior body 5 is broken at a portion adjacent to the seal portion S, and the breakage of the exterior body 5 progresses in the lateral direction Y outward along the longitudinal direction of the seal portion S, a so-called lateral joint. Cracking may occur. If the exterior body 5 is torn laterally, the tearing action is interrupted each time, which causes great stress to the disposal person and the wearer.

On the other hand, in the present embodiment, of the two seal portions S that belong to different seal rows SL and are adjacent in the lateral direction Y, the seal portion S positioned on the inner side in the lateral direction Y is the seal portion S located on the outer side in the lateral direction Y. It has lower seal strength than S.
“Two seal portions S adjacent to each other in the horizontal direction Y” means one seal portion S when the position of each seal portion S that is divided into two equal parts in the horizontal direction Y and the vertical direction X is defined as the “central portion”, The other seal portion S having a center portion closest to the center portion of the seal portion S and two seal portions S are meant.
Thus, in the present invention, at least the relationship between the seal strengths of two adjacent seal portions S should satisfy the above relationship.

In this embodiment, it is preferable that the seal strength of the seal portion S gradually increases from the inner seal row SL in the lateral direction Y toward the outer seal row SL.
In the example shown in FIG. 3, the seal strength of each seal portion S of the first seal row SL1 is lower than the seal strength of each seal portion S of the second seal row SL2. Similarly, the seal strength of each seal portion S of the second seal row SL2 is lower than the seal strength of each seal portion S of the third seal row SL3. That is, the seal strength of the seal portion S increases in the horizontal direction Y in the order of the innermost first seal row SL1, the outermost second seal row SL2, and the outermost third seal row SL3.
As used herein, seal strength refers to peel strength measured by a measuring device such as Tensilon. Moreover, the peel strength refers to the local peel strength measured by a measuring device such as Tensilon. On the other hand, the joint strength refers to the strength of joint felt by the disposal person when the side joint portion 8 is torn.
In the above configuration, the seal strength of the seal portion S of the seal row SL (for example, the first seal row SL1) on the inner side in the lateral direction Y to which the tearing force F is applied first is low. This makes it easier for the person who disposes to easily tear the seal portion S at the beginning, and makes it difficult to apply a strong force to the side joint portion 8 .
Furthermore, when two diagonally adjacent seal portions S are torn at the same time, the seal strength of one seal portion S becomes lower than the seal strength of the other seal portion S. As a result, the total seal strength of the two seal portions S can be kept low compared to the case where all seal portions S have the same seal strength. Therefore, even in the middle of tearing, the tearing force F by the disposal person is less likely to increase, and the load on the exterior body 5 is reduced.
As a result, tearing can be easily felt, and lateral tearing of the exterior body 5 can be prevented.
In addition, since the seal strength of the seal line SL (for example, the third seal line SL3) on the outer side in the lateral direction Y can be set high, it is possible to prevent peeling during wearing and wearing operation.
Therefore, in the side joint portion 8 of the present embodiment, it is possible to achieve both the prevention of peeling during wearing and the wearing operation and the easiness of tearing during disposal.

<Method for measuring seal strength>
A method for measuring and comparing the seal strength of the seal portion S of each seal row SL will be described.
First, at least one of the waist end region 8c and the leg end region 8d including a plurality of seal rows SL is cut into a rectangular shape having a length of 10 mm in the longitudinal direction X and a length including the full width of the side joint portion 8 in the lateral direction Y. to form a sample for measurement. The total width of the side joint portion 8 is the length from the outer side edge in the lateral direction Y of the side joint portion 8 to the inner end portion of the innermost laterally Y inner seal portion S in the lateral direction Y. The length of the measurement sample in the lateral direction Y is preferably 20 mm or more longer inward in the lateral direction Y than the entire width in order to secure a portion to be fixed to the tensilon. The plurality of cut out measurement samples are assumed to have the same laminated number of thermoplastic sheets 50 .
Subsequently, the inner end portion of the measurement sample in the lateral direction Y is fixed to a Tensilon universal tester (RTC-1210A) manufactured by Orientec Co., Ltd., and one outer package 5 is separated from the other outer package 5 . The measurement sample is peeled from the inner side to the outer side in the lateral direction Y at a speed of 10 mm/min, and the peel strength is measured over time.
FIG. 5 shows an example of a graph obtained by measuring seal strength as described above. In FIG. 5, the vertical axis indicates the seal strength (N), and the horizontal axis indicates the distance from the peeling start point in the horizontal direction Y. As shown in FIG.
From this graph, a plurality of peak intensities A, B, and C can be confirmed corresponding to a plurality of seal rows SL. These peak strengths A, B, and C are the seal strengths of the seal portions S of each seal row SL arranged along the lateral direction Y from the inner side to the outer side. When the peak strength B is lower than the peak strength C, or when the peak strength A is lower than the peak strength B, the seal portion S positioned inside in the lateral direction Y is greater than the seal portion S positioned outside in the lateral direction Y. are also determined to have low seal strength.

A specific example of the seal strength of the seal portion S will be given.
The seal strength of the seal portion S of the seal row SL (for example, the first seal row SL1) on the innermost side in the lateral direction Y is preferably 0.1 N or more, more preferably 0.2 N, from the viewpoint of facilitating tearing during disposal. or more, preferably 2N or less, more preferably 1.8N or less.
The seal strength of the seal portion S of the seal row SL on the outermost side in the lateral direction Y (for example, the third seal row SL3) is preferably 0.5 N or more, more preferably 0.5 N or more, from the viewpoint of preventing peeling during wearing and wearing. It is 0.7N or more, preferably 5N or less, more preferably 4N or less.
The ratio of the seal strength of the seal portion S of the innermost seal line SL (for example, the first seal line SL1) to the seal strength of the seal portion S of the seal line SL (for example, the third seal line SL3) that is the outermost in the lateral direction Y The ratio is preferably 5% or more, more preferably 10% or more, and preferably 90% or less, more preferably 80% or less, from the viewpoint of achieving both peeling prevention and tearability.

[Example of method for adjusting seal strength]
The seal strength of the seal portion S can be adjusted, for example, by changing conditions such as temperature, pressure and/or time during the sealing process for forming the seal portion S.
Alternatively, the seal strength can be reduced by disposing a melting inhibitor between the thermoplastic sheets 50 to inhibit melting of the resin. Melting inhibitors include hot-melt adhesives, polyurethane-based materials, petroleum-based resins, and the like.
The seal strength can also be adjusted by changing the area of the seal portion S, which is the fused portion of the fibers.
The seal strength can also be adjusted by changing the fiber composition of the thermoplastic sheet 50 .
Specific examples will be described below.

(Example of adjustment by melting degree of fibers)
The seal portion S is a portion formed by fusing fibers of a plurality of thermoplastic sheets 50 of the exterior body 5 . For this reason, in the sealing portion S in which the fibers are sufficiently melted, the fibers tend to adhere to each other after cooling, and the sealing strength tends to be high.
Therefore, of the two seal portions S that belong to different seal rows SL and are adjacent to each other in the horizontal direction Y, the seal portion S that is located inside in the horizontal direction Y has a higher fiber density than the seal portion S that is located outside in the horizontal direction Y. A low degree of melting is preferred. For example, it is preferable that the degree of melting of the seal portions S increases from the seal row SL on the inner side in the lateral direction Y toward the seal row SL on the outer side.
For example, the melting degree of the fibers of the seal portion S increases in the horizontal direction Y in the order of the innermost first seal row SL1, the outermost second seal row SL2, and the outermost third seal row SL3.

<Method for calculating the degree of melting of the seal>
First, the waist end region 8c and/or the leg end region 8d including the seal row SL of the side joint portion 8 are cut, and an XZ cross section of the seal portion S (a cross section crossing the seal portion S in the longitudinal direction X) is obtained. Prepare a sample for measurement containing The seal portions S to be measured are the seal portions S belonging to each seal line SL, and the seal portions S located in the region where the number of laminated thermoplastic sheets 50 is the same.
After fixing the measurement sample by a known method, the XZ cross section of the measurement sample is imaged with a scanning electron microscope (SEM) at a magnification of 500 times. In each captured image, image analysis software is used to detect the outer edge of the fiber, and the length of the detected line is calculated as the perimeter of the fiber. For each seal row SL, the average value of the fiber perimeters calculated from five or more images is calculated, and the average value is taken as the fiber perimeter of the seal portion S of each seal row SL.
The perimeters of the fibers of the seal portions S of the plurality of seal rows SL are compared, and it is determined that the longer the perimeter of the fiber, the lower the degree of melting.

FIG. 6A shows an example of an enlarged view of the XZ cross section of the seal portion S belonging to the seal row SL on the inside in the lateral direction Y, and FIG. 6B shows an example of an enlarged view of the seal row SL on the outside in the lateral direction Y. An example of an enlarged view of the XZ cross section of the seal portion S is shown.
The fiber 55 shown in FIG. 6(A) includes many irregularities on the outer edge 55a and has a long circumference. That is, the fibers 55 are not melted so much, and the original unevenness of the fibers 55 remains on the outer edge 55a which is the surface.
On the other hand, the fiber 55 in FIG. 6B has a relatively smooth outer edge 55a and a shorter circumference than the fiber 55 in FIG. 6A. That is, the fibers 55 are sufficiently melted, and the unevenness of the outer edge 55a is smoothed.
In this case, it is determined that the degree of melting of the fibers 55 in the seal portion S in FIG. 6A is lower than the degree of melting of the fibers 55 in the seal portion S in FIG. 6B.

The degree of melting of the fibers can be adjusted by conditions such as heat, pressure and/or time during the sealing process. By adjusting the sealing strength according to the degree of fusion of the fibers, the sealing strength can be adjusted without significantly changing the planar shape, arrangement, or thickness of the sealing portion S. By aligning the planar shape and arrangement of the seal portions S, the seal portions S can be torn one after another at substantially constant intervals when tearing. Therefore, the tearing operation can be stably and smoothly performed, and the stress of the disposal person can be reduced.
Further, the melting degree of the fibers can be changed without changing the composition of the fibers of the thermoplastic sheet 50 for each seal row SL. Thereby, the seal strength can be adjusted relatively easily and accurately.

The seal portion S of the innermost seal row SL in the lateral direction Y (for example, the first seal row SL1) with respect to the fiber circumference of the seal portion S of the seal portion S in the outermost seal row SL in the lateral direction Y (for example, the third seal row SL3) The fiber perimeter ratio is preferably 105% or more, more preferably 110% or more, and preferably 300% or less, more preferably 200% or less.

(Example of adjustment by thickness of seal part)
Further, by greatly compressing the superimposed thermoplastic sheets 50 in the thickness direction Z during the sealing process, the melted fibers are strongly crimped, and the sealing strength of the sealing portion S can be increased. That is, the thinner the seal portion S, the higher the seal strength.
Therefore, of the two seal portions S that belong to different seal rows SL and are adjacent in the lateral direction Y, the seal portion S located inside in the lateral direction Y is configured to be thicker than the seal portion S located outside in the lateral direction Y. may be For example, it is preferable that the thickness of the seal portion S decreases from the seal row SL on the inner side in the lateral direction Y toward the seal row SL on the outer side. The thickness of the seal portion S referred to here is the thickness along the thickness direction Z. As shown in FIG.
For example, the thickness of the seal portion S decreases in the horizontal direction Y in the order of the innermost first seal row SL1, the outermost second seal row SL2, and the outermost third seal row SL3.

<Method for measuring the thickness of the seal>
First, the waist end region 8c and/or the leg end region 8d including the seal row SL of the side joint portion 8 are cut, and an XZ cross section of the seal portion S (a cross section crossing the seal portion S in the longitudinal direction X) is obtained. Prepare a sample for measurement containing The seal portions S to be measured are the seal portions S belonging to each seal line SL, and the seal portions S located in the region where the number of laminated thermoplastic sheets 50 is the same. After fixing the measurement sample by a known method, the XZ cross section of the measurement sample is imaged by SEM or the like at a magnification of 500 times. Then, as shown in FIG. 4, the recessed portion in the captured image is defined as the seal portion S. As shown in FIG. Using image analysis software, the thickness Ds (see FIG. 4) in the thickness direction Z of the portion that bisects the seal portion S in the width direction (longitudinal direction X) is calculated as the thickness of the seal portion S. For each seal line SL, an average value of the thickness of the seal portion S calculated from five or more images is calculated, and the average value is used as the thickness of the seal portion S of each seal line SL.

The ratio of the thickness of the seal portion S of the innermost seal row SL (for example, the first seal row SL1) to the thickness of the seal portion S of the seal row SL that is the outermost in the transverse direction Y (for example, the third seal row SL3) is , preferably 102% or more, more preferably 104% or more, preferably 200% or less, more preferably 180% or less.

(Example of adjustment based on the area of the seal)
Alternatively, the seal strength of the seal portion S can be adjusted by the area of the seal portion S as well. Specifically, the smaller the area of the seal portion S, the smaller the area of the fused portion of the fibers, and the lower the seal strength.
Therefore, of the two seal portions S that belong to different seal rows SL and are adjacent in the lateral direction Y, the seal portion S positioned inside in the lateral direction Y has a smaller area than the seal portion S positioned outside in the lateral direction Y. may have For example, the area of the seal portion S may increase from the inner seal row SL in the lateral direction Y toward the outer seal row SL. The area of the seal portion S referred to here is the area of one seal portion S in plan view. The seal portions S to be compared are the seal portions S belonging to each seal line SL of the waist end region 8c and/or the leg end region 8d. If the planar shapes of the seal portions S are different within the same seal line SL, the average area of any five seal portions S located in the end region to be measured within one seal line SL is The area of the seal portion S of the seal row.
For example, the area of the seal portion S preferably increases in the horizontal direction Y in the order of the innermost first seal row SL1, the outermost second seal row SL2, and the outermost third seal row SL3.

Thereby, the seal strength of the seal portion S can be adjusted by changing the seal pattern without changing the conditions of the sealing process for each seal row SL. Therefore, the seal strength of the seal portion S within the first seal row SL1 on the inner side in the lateral direction Y can be reduced more stably.

[Example of seal arrangement]
A more specific arrangement example of the seal portions S in two seal rows SL adjacent to each other in the lateral direction Y will be described.
For example, as shown in FIG. 7, when the outermost seal row SL in the lateral direction Y is the outermost seal row SLb, and the inner seal row SLa is the seal row SL adjacent to the outer seal row SLb on the inner side in the lateral direction Y. Further, the distance in the lateral direction Y between the outer end Sb of the seal portion S of the outer seal row SLb in the lateral direction Y and the inner end Sa of the seal portion S of the inner seal row SLa in the lateral direction Y is Let the first dimension be D1.
From the viewpoint of increasing the sealing strength of the entire side joint portion 8 and suppressing tearing during wearing and wearing operation, a large number of seal portions S are provided along the longitudinal direction X in the side joint portion 8 that is long in the longitudinal direction X. is preferably placed.
For this reason, in the outer seal row SLb, it is preferable that the plurality of seal portions S are arranged in the vertical direction X at intervals of a second dimension D2 that is narrower than the first dimension D1.
Since the width of the side joint portion 8 in the lateral direction Y is restricted to some extent, the first dimension D1 is also restricted accordingly. Using this first dimension D1 as a reference, the distance between the outer seal rows SLb in the longitudinal direction X is set to a second dimension D2 narrower than the first dimension D1, thereby forming a seal portion S having a high seal strength along the longitudinal direction X. They can be arranged densely, and the joint strength of the side joints 8 can be sufficiently secured.

On the other hand, at the start of tearing, an oblique force F including a component directed toward the center in the vertical direction X and a component directed toward the outer side in the horizontal direction Y is applied. Since the tear at the waist end region 8c or the leg end region 8d on the tear initiation side progresses along the direction of this force F, the peel interface moves along the direction orthogonal to this. That is, the separation interface is formed on the line L along the direction including the component toward the center in the vertical direction X and the component toward the inner side in the horizontal direction Y. The line L is inclined at approximately 45° with respect to the vertical direction X and the horizontal direction Y. As shown in FIG.
As shown in FIG. 7, in an arrangement that satisfies D1>D2, a plurality of seal portions S are arranged on line L, and these seal portions S are torn at the same time. That is, when tearing, a force greater than the total seal strength of these seal portions S is surely required.

On the other hand, in the present embodiment, the seal strength of the seal portions S of the inner seal row SLa is smaller than the seal strength of the seal portions S of the outer seal row SLb. Therefore, an increase in the total seal strength of the two seal portions S can be suppressed, and tearing can be performed with a weak force. In addition, it is possible to suppress the local application of a large force to the exterior body 5, and effectively prevent the exterior body 5 from being laterally torn.

A more specific arrangement of the seal portion S will be described.
As shown in FIG. 3, the plurality of seal portions S included in the plurality of seal rows SL are preferably aligned along the lateral direction Y. As shown in FIG. That is, the seal portions S in at least one of the waist end region 8c and the leg end region 8d in which the seal rows SL are arranged may be arranged in a grid pattern aligned along the longitudinal direction X and the lateral direction Y. preferable.
“A plurality of seal portions S are aligned along the horizontal direction Y” means that the plurality of seal portions S are aligned and arranged on a straight line extending in the horizontal direction Y. Specifically, it is preferable that the deviation of the straight line that bisects each seal portion S in the longitudinal direction X is within 50% of the dimension of the seal portion S in the longitudinal direction X.

In the above configuration, since the seal portions S are regularly arranged, the seal strength may fluctuate regularly. As a result, the drag force that the disposal person receives during tearing tends to fluctuate regularly, and the disposal person can tear the sheet more smoothly and easily.

In addition, in the side joint portion 8, a non-sealed portion is arranged around the seal portion S. As shown in FIG. When the disposal person tries to tear the side joint portion 8 continuously, if the difference in resistance received between the seal portion S and its surrounding portion is too large, the tearing operation tends to feel uncomfortable.
From the viewpoint of suppressing the discomfort of such a tearing action, at least one of the waist end region 8c and the leg end region 8d including the plurality of seal rows SL is 10 mm in the longitudinal direction X and the side joints 8 are 10 mm in the lateral direction Y. When measuring the seal strength by cutting out a rectangular shape with a length including the full width of the measurement sample and peeling the measurement sample from the inside to the outside in the lateral direction Y at a speed of 10 mm / min, It is preferable that the minimum intensity between the plurality of peak intensities corresponding to the seal rows SL of 1 is greater than 0N. As this measuring method, the method described in the above-described method for measuring seal strength can be used.
Moreover, the above configuration can be achieved by making the distance between the seal portions S in the lateral direction Y of the seal row SL shorter than the seal width of the seal portions S in the lateral direction Y.

These peak and minimum intensities can be read from graphs such as those shown in FIG.
In the example shown in FIG. 5, peak intensities A, B, and C corresponding respectively to the first seal row SL1, the second seal row SL2, and the third seal row SL3 are shown. Let the minimum intensity between peak intensities A and B be a. Let the minimum intensity between peak intensities B and C be b. That is, the minimum intensity b is the intensity measured outside the minimum intensity a in the lateral direction Y.

Since the minimum intensities a and b are larger than 0N, the difference between the minimum intensities a and b and the peak intensities B and C that appear next thereto is suppressed from increasing rapidly. That is, the rate of increase in seal strength per unit length from the minimum strengths a and b to the peak strengths B and C that appear next can be suppressed.
The inventors have confirmed that the seal strength distribution obtained under the above measurement conditions approximates the seal strength distribution obtained when the side joint portion 8 is actually torn.
Therefore, according to the above configuration, even when the side joint portion 8 is actually torn, it is possible to reduce the fluctuation of the drag force that the disposal person receives over time, and it is possible to obtain the side joint portion 8 that is easy to tear.

Furthermore, three or more seal rows SL are arranged as a plurality of seal rows SL in at least one of the waist end region 8c or the leg end region 8d, and the seal strength was measured using the measurement sample described above. In some cases, the minimum intensities between the three or more peak intensities preferably increase in order measured from the inside to the outside in the transverse direction Y.

First, the peak intensity when three or more seal rows SL are arranged will be described.
When three or more seal rows SL are arranged, the seal strength of the seal portions S of these seal rows SL increases from the inner side to the outer side in the lateral direction Y. For example, in the graph of FIG. 5, peak intensities A, B and C increase in this order. As a result, the disposal person can be guided to gradually apply force, and lateral tearing of the outer package 5 due to sudden application of a large force can be suppressed. In addition, since a large force is not required at the start of tearing, even a disposer with weak force can easily tear. Therefore, it is possible to obtain the side joints 8 that are less likely to be laterally torn at the time of disposal and are easier to tear.

Next, the minimum strength when three or more seal rows SL are arranged will be described.
In the example shown in FIG. 5, the minimum intensity b between the peak intensities B and C is greater than the minimum intensity a between the peak intensities A and B. As a result, even when the peak intensities A, B, and C increase in this order, the difference between the minimum intensities a, b and the peak intensities B, C appearing next thereto is suppressed from increasing rapidly. As a result, the increase rate of the seal strength per unit length from the minimum strengths a and b to the peak strengths B and C appearing next can be suppressed more effectively.
Therefore, according to the above configuration, even when the side joint portion 8 is actually torn, it is possible to further reduce the fluctuation of the drag force that the disposal person receives over time, and it is possible to obtain the side joint portion 8 that is easier to tear. can.

From the viewpoint of easily obtaining the peak strength and the minimum strength that satisfy the above conditions, the seal portion S can be arranged as follows.
The fact that the minimum intensities a and b between the peak intensities A, B, and C are greater than 0 N means that when the measurement sample is peeled from the inner side in the lateral direction Y toward the outer side, the seal portion S on the inner side in the lateral direction Y is It means that peeling of the outer seal portion S is started before it is completely peeled off. Therefore, referring to FIG. 7, the lateral direction of the seal portion S of the inner seal row SLa is relative to the distance D3 in the lateral direction Y between the seal portion S of the outer seal row SLb and the adjacent seal portion S of the inner seal row SLa. The dimensional ratio in Y (D4/D3) is preferably 0.2 or more, more preferably 0.3 or more.
As a result, the gap D3 between the inner seal row SLa and the outer seal row SLb is narrowed, and the peeling of the seal portion S of the outer seal row SLb is started before the seal portion S of the inner seal row SLa is completely peeled off. can do. Therefore, the minimum intensities a and b can be made greater than 0N.

Further, in at least one of the waist end region 8c and the leg end region 8d where three or more seal lines SL are arranged, the interval between the seal portions S of the seal lines SL adjacent to each other in the lateral direction Y is may be configured to decrease outwardly from the As a result, the width between peak intensities can be decreased from the inner side to the outer side in the lateral direction Y, making it easier to increase the minimum intensity.

[Example of dimensions related to the seal part]
The dimensions of the seal portion S belonging to the seal line SL include the following examples from the viewpoint of achieving both the prevention of peeling during the wearing operation and wearing and the easiness of tearing. In addition, the following dimensions shall be measured in the natural state which is not extending|stretching an elastic member.
The dimension (maximum dimension) of the seal portion S in the lateral direction Y is preferably 0.15 mm or more, more preferably 0.2 mm or more, and is preferably 7 mm or less, more preferably 5 mm or less.
The pitch of the plurality of seal rows SL in the lateral direction Y is preferably 0.4 mm or more, more preferably 0.7 mm or more, and is preferably 7 mm or less, more preferably 4 mm or less.
In addition, the pitch in the horizontal direction Y of the plurality of seal rows SL is the distance in the horizontal direction Y between the lines that bisect each seal portion S in the horizontal direction Y in the seal portions S adjacent to each other in the horizontal direction Y. means. If the pitch is not constant, the pitches in the lateral direction Y are measured at five locations, and the average value thereof is taken as the lateral Y pitch.
The dimension (maximum dimension) in the longitudinal direction X of the seal portion S included in the seal row SL is preferably 0.1 m or more, more preferably 0.3 mm or more, and is preferably 2 mm or less, more preferably 0.6 mm. It is below.
The pitch in the longitudinal direction X of the plurality of seal portions S included in the seal row SL is preferably 1.5 mm or more, more preferably 1.7 mm or more, and is preferably 5.0 mm or less, more preferably 4 mm or less. be.
The pitch in the longitudinal direction X of the plurality of seal portions S means the distance in the longitudinal direction X between the lines dividing each seal portion S into two equal parts in the longitudinal direction X in the seal portions S adjacent to each other in the longitudinal direction X. If the pitch is not constant, the pitch in the vertical direction X is measured at five locations, and the average value thereof is taken as the pitch in the vertical direction X.

[Configuration example of elastic member]
As shown in FIG. 2, the ventral region 5a and the dorsal region 5b of the armor 5 include a plurality of elastic members 10 extending in the horizontal direction Y. As shown in FIG.
The plurality of elastic members 10 are arranged between the plurality of thermoplastic sheets 50 of the exterior body 5 (see FIG. 9).
These elastic members 10 exhibit stretchability around the waist of the diaper 1, facilitate the wearing operation, and maintain the fit when worn.
In addition, "the elastic member 10 extends in the lateral direction Y" means that the elastic member 10 extends in the lateral direction Y in the deployed and extended state. However, the above expression is not limited to a mode in which the elastic member 10 is parallel to the lateral direction Y in the deployed and stretched state, and includes a mode in which the elastic member 10 extends in the lateral direction Y as a whole.
Furthermore, as shown in FIG. 2, the outer body 5 may include leg elastic members 11 arranged around the leg openings 1L in addition to the elastic members 10 described above.

The

elastic members

10 and 11 preferably have a rectangular, square, circular, polygonal cross section, and are thread-like (string rubber, etc.) or string-like (flat rubber, etc.), or multi-filament type thread-like ones. can. The materials of the

elastic members

10 and 11 can be those conventionally used in absorbent articles such as disposable diapers without particular limitation. EVA, elastic polyolefin, polyurethane and the like can be mentioned.

From the viewpoint of ensuring the stretchability of the entire waist circumference, the lateral Y outer end of the elastic member 10 of each of the ventral region 5a and the dorsal region 5b is preferably positioned at or near the side joint 8. preferable. Specifically, the end preferably has a distance of 10 mm or less from the side joint 8 in the lateral direction Y, and the distance is 0 mm and the end is positioned inside the side joint 8. is more preferable.
The elastic member 10 is generally arranged up to or near a region where force is applied during tearing, which tends to affect the ease of tearing during disposal.
Therefore, from the viewpoint of improving the ease of tearing at the time of disposal and making it easier to follow the waist circumference where the waist circumference tends to change depending on the wearer's posture, the elastic member is formed in a region including and not including the waist end region 8c. It is preferable to adjust the elongation rate as follows.

As shown in FIG. 2, the ventral region 5a and the dorsal region 5b respectively have a first stretchable region 5f and a second stretchable region 5g in which a plurality of elastic members 10 extending in the lateral direction Y are arranged. The first stretchable region 5f and the second stretchable region 5g each extend in the horizontal direction Y from one of the pair of side joints 8 to the other. That is, the first stretchable region 5f and the second stretchable region 5g extend over the entire width in the horizontal direction Y of the ventral region 5a and the dorsal region 5b.
The first elastic region 5f extends in the lateral direction Y from the waist end region 8c. That is, both lateral Y ends of the first stretchable region 5f are constituted by the waist end regions 8c.
The second stretchable region 5g is adjacent to the first stretchable region 5f in the longitudinal direction X and extends in the lateral direction Y from the region of the side joint 8 excluding the waist end region 8c.

In this configuration, the average stretch rate of the plurality of elastic members 10 in the first stretchable region 5f is preferably lower than the average stretch rate of the plurality of elastic members 10 in the second stretchable region 5g.
The stretch ratio of the elastic member 10 means the ratio of the length of the elastic member stretched in the unfolded and stretched state of the pants-type absorbent article to the length of the elastic member in the natural length taken out from the pants-type absorbent article. .
That is, the lower the elongation rate, the smaller the elastic force when the elastic member 10 is pulled.
The extension rate of the elastic member 10 can be adjusted by adjusting the degree of extension of the elastic member 10 arranged on the exterior body 5 at the time of manufacturing. During manufacturing, for example, the elastic member 10 is stretched to a predetermined length, an adhesive is applied to the elastic member 10 with a comb or the like, and the elastic member 10 is fixed to the thermoplastic sheet 50 of the exterior body 5 .

A force in the lateral direction Y can be directly applied to the waist end region 8c during the tearing operation, as described above. In the above configuration, since the average elongation rate of the elastic member 10 in the first elastic region 5f is low, the elastic force of the elastic member 10, which acts as a resistance against the tearing force, is low. As a result, the energy associated with the tearing force is less likely to be consumed by the elongation of the elastic member 10, and even a weaker force can efficiently tear. Therefore, with the above configuration, a stable tearing operation becomes possible, and troubles such as tearing of the exterior body 5 due to excessive tearing force can be prevented.

<Method for measuring average elongation of elastic member>
The side joints 8 of the pants-type absorbent article are separated, the absorbent main body 4 is removed, and the ventral region 5a and the dorsal region 5b of the exterior body 5 are cut out. Furthermore, a position of 25 mm in the longitudinal direction X from the waist end 8a (waist opening end Wa) and/or the leg end 8b of the abdominal region 5a and the dorsal region 5b is cut parallel to the lateral direction Y, and the first stretching A region 5f and a second elastic region 5g are cut out.
Then, the length of the elastic member 10 in each cut-out region is measured in the unfolded and stretched state of the pants-type absorbent article. From this measured value, the average value of the lengths of all the elastic members 10 in the maximum stretched state in each of the

regions

5f and 5g is calculated.
All the elastic members 10 fixed to the

regions

5f and 5g by adhesive or the like are removed from the other constituent members of the exterior body 5 using a suitable solvent such as ethyl acetate, and the natural lengths of the

regions

5f and 5g are removed. The length of elastic member 10 is measured. From this measured value, the average value of the lengths of all the natural lengths of the elastic members 10 in each of the

regions

5f and 5g is calculated.
Then, in each of the

regions

5f and 5g, the ratio of the average length of the elastic member 10 in the unfolded and stretched state to the average length of the elastic member 10 in the natural length is calculated. Let it be the average elongation rate of the elastic member 10 .

The average stretch rate of the plurality of elastic members 10 in the first elastic region 5f is preferably 120% or more, more preferably 130% or more, and preferably 500% or less, more preferably 450% or less.
The average stretch rate of the plurality of elastic members 10 in the second elastic region 5g is preferably 150% or more, more preferably 180% or more, and preferably 550% or less, more preferably 500% or less.
The ratio of the average elongation rate of the plurality of elastic members 10 in the first elastic region 5f to the average elongation rate of the plurality of elastic members 10 in the second elastic region 5g is preferably 20 from the viewpoint of effectively obtaining the above effects. % or more, more preferably 30% or more, preferably 90% or less, more preferably 80% or less.

Further, when the elastic member 10 extends to the side joint portion 8 in the lateral direction Y, the strength of the seal portion S is likely to be lowered at the position where the elastic member 10 and the seal portion S overlap each other in plan view. In particular, when the elastic member 10 is arranged on the exterior body 5 via a hot-melt adhesive, the hot-melt adhesive hinders the fusion of the seal portion S, and the strength of the seal portion S is likely to be further reduced. Become.
From the viewpoint of suppressing the overlapping of the elastic members 10 and the seal portions S in plan view, as shown in FIG. and not an integral multiple of the pitch D4 in the longitudinal direction X of the plurality of seal portions S.
Note that the pitch D5 of the plurality of elastic members 10 in the vertical direction X is the distance in the vertical direction X between the lines dividing each elastic member 10 into two equal parts in the vertical direction X in the elastic members 10 adjacent to each other in the vertical direction X. means.

As a result, the pitches of the elastic member 10 and the seal portion S in the longitudinal direction X do not match, and it is possible to suppress their overlap in plan view. Furthermore, since the pitch D5 of the elastic member 10 in the longitudinal direction X is larger than the pitch D4 of the seal portions S in the longitudinal direction X, the pitch of the seal portions S is narrowed and the seal portions S are densely arranged in the longitudinal direction X. , and peeling of the side joint portion 8 can be suppressed. In addition, since the pitch of the elastic member 10 in the longitudinal direction X is not an integral multiple of the pitch of the seal portion S in the longitudinal direction X, it is possible to suppress the overlap in plan view, and the strength of the seal portion S caused by the elastic member 10. can be suppressed. Therefore, the strength of the seal portion S can be adjusted with high accuracy.

[Configuration example of exterior body]
As shown in FIG. 9 , the exterior body 5 preferably includes, for example, an outer layer sheet 51 and an inner layer sheet 52 as a plurality of thermoplastic sheets 50 . The outer layer sheet 51 is arranged on the non-skin side of the inner layer sheet 52 and forms the non-skin facing surface of the exterior body 5 . For example, an elastic member 10 is arranged between the inner layer sheet 52 and the outer layer sheet 51 .
In the present embodiment, at least part of the exterior body 5 is folded back from the waist opening end Wa toward the skin side, so that the exterior body 5 has a folded structure. In the example shown in FIG. 9, only the outer layer sheet 51 is folded back from the waist end 8a to the skin side.
In addition, in the cross-sectional view of FIG. 9, for the sake of explanation, the ventral region 5a and the dorsal region 5b of the side joint portion 8 are shown in a separated state.

In this embodiment, as shown in FIG. 9 , the side joint portion 8 has a plurality of regions in which the thermoplastic sheets 50 are laminated in different numbers due to the folded structure of the exterior body 5 .
That is, in the present embodiment, the side joint portion 8 includes a first laminated portion T1 in which six or more thermoplastic sheets 50 are laminated, and a second laminated portion T1 in which a smaller number of thermoplastic sheets 50 than the first laminated portion T1 are laminated. 2 laminated portion T2. In the present embodiment, the first laminated portion T1 corresponds to a region where the exterior body 5 is folded back, and the waist end region 8c is arranged in the first laminated portion T1. The first laminated portion T1 includes, as the thermoplastic sheet 50, a first skin-side sheet P1 forming a skin-facing surface. The second laminated portion T2 includes, as the thermoplastic sheet 50, a second skin-side sheet P2 that constitutes the skin-facing surface.

In the example shown in FIG. 9, the first laminated portion T1 of the ventral region 5a is composed of three layers: an outer layer sheet 51 that is not folded back, an inner layer sheet 52 that is not folded back, and an outer layer sheet 51 that is folded back. be done. The first laminated portion T1 of the dorsal region 5b is also composed of the same three layers. Thus, the first laminated section T1 is composed of a total of six layers. In the first laminated portion T1, the first skin side sheet P1 is composed of the outer layer sheet 51 folded back.
In the example shown in FIG. 9, the second laminated portion T2 of the ventral region 5a is composed of two layers, an outer layer sheet 51 that is not folded back and an inner layer sheet 52 that is not folded back. The second laminated portion T2 of the dorsal region 5b is also composed of two similar layers. As a result, the second lamination part T2 is composed of a total of four layers. In the second laminated portion T2, the second skin side sheet P2 is composed of the inner layer sheet 52 that is not folded back.

Since the number of laminated thermoplastic sheets 50 is larger in the first laminated portion T1 than in the second laminated portion T2, the amount of thermoplastic resin is also increased. Therefore, the first laminated portion T1 has a larger amount of heat-sealed resin than the second laminated portion T2, and the sealing strength of the seal portion S tends to be high.
Therefore, by adjusting the pattern of the seal portion S of the first laminated portion T1 and the second laminated portion T2, the bonding strength between the first laminated portion T1 and the second laminated portion T2 is adjusted, and the tearing stability is improved. be able to.

[Example of Planar Shape and/or Arrangement of Seal Portions in First Laminated Part and Second Laminated Part]
When the side joint portion 8 has the first laminated portion T1 and the second laminated portion T2, the side joint portion 8 extends across the entire width of the side joint portion 8 in the horizontal direction Y and is adjacent to the side joint portion 8 in the longitudinal direction X. It is preferable to have one sealing area R1 and a second sealing area R2.
As exemplified in FIGS. 10(A), (B) and FIGS. 11(A), (B), the first sealing region R1 and the second sealing region R2 are a plurality of seals having a regular planar shape and arrangement. Part S, respectively. At least one of the planar shape and arrangement of the plurality of seal portions S is different between the first seal region R1 and the second seal region R2.
“The plurality of seal portions S have a regular planar shape” means that all the seal portions S within the region have substantially the same planar shape, or that the plurality of seal portions S have a plurality of types of planar shapes. It means at least one of having a shape and having seal portions S of different planar shapes arranged regularly.
“A plurality of seal portions S are regularly arranged” means that the pitch of the seal portions S in the longitudinal direction X and the lateral direction Y is substantially the same, or that the pitch changes regularly. means at least one of

The first seal area R1 and the second seal area R2 are ranges each having a certain seal pattern. In the examples shown in FIGS. 10 and 11, the first seal region R1 extends in the longitudinal direction X from one end (for example, the waist end 8a) to the portion where the seal pattern is changed. Similarly, the second seal region R2 extends in the longitudinal direction X from the other end (for example, the leg end 8b) to the portion where the seal pattern is changed. A boundary line Ra between the first seal area R1 and the second seal area R2 is a line that bisects the gap between the seal portions S that are adjacent in the longitudinal direction X at the boundary between the first seal area R1 and the second seal area R2. If the boundary line Ra is not linear due to the arrangement of the seal rows SL, etc., the boundary line Ra is defined as a curved line connecting the ends of a plurality of lines that divide the gap into two equal halves.
In addition, the full width of the side joint portion 8, which is also the width of the first sealing region R1 and the second sealing region R2, extends from the outer edge of the side joint portion 8 in the horizontal direction Y to the innermost side in the horizontal direction Y of the side joint portion 8. The dimension in the horizontal direction Y to the inner end Sa of the seal portion S located.

In the present embodiment, at least a portion of the first laminated portion T1 is arranged in the first seal region R1. At least a portion of the second laminated portion T2 is arranged in the second seal region R2. For example, the first seal region R1 is located on the waist end portion 8a side where the outer body 5 is folded back, and the second seal region R2 is located on the leg end portion 8b side.

From the viewpoint of reducing the difference in bonding strength between the first laminated portion T1 and the second laminated portion T2, the ratio of the total area of the plurality of seal portions S to the total area of the first seal region R1 is It is preferably smaller than the ratio of the total area of the plurality of seal portions S to the whole. Hereinafter, the ratio of the total area of the plurality of seal portions S to the total area of each of the regions R1 and R2 is also referred to as "seal area ratio."
With this configuration, the seal area ratio of the first laminated portion T1, which has a large amount of heat-sealed resin, can be made smaller than the seal area ratio of the second laminated portion T2. Therefore, an increase in the bonding strength of the first laminated portion T1 to the second laminated portion T2 can be suppressed, and the tearing stability of the side joint portion 8 can be enhanced.

Further, the boundary line Ra between the first sealing region R1 and the second sealing region R2 is often deviated from the boundary between the first laminated part T1 and the second laminated part T2 in terms of manufacturing. In this case, as shown in FIGS. 10A and 11A, the first seal region R1 preferably extends from the first laminated portion T1 to part of the second laminated portion T2. In other words, it is preferable that a part of the first seal region R1 with a small seal area ratio be arranged in the second laminated portion T2 where the seal strength tends to be small.
In this configuration, a region with a smaller seal strength is arranged near the boundary of the second laminated portion T2. As a result, the bonding strength between the first lamination part T1 and the second lamination part T2 does not suddenly increase, and it is possible to suppress the discomfort of the waste person due to the change in the number of lamination. In addition, since the joint strength is lowered once, the disposal person can rest his/her hands in the middle of tearing, and the burden of tearing on the disposal person can be reduced. Therefore, the ease of tearing of the side joint portion 8 can be enhanced more effectively.

(Width of the area where the seal part is arranged)
A specific example of a method for adjusting the sealing area ratios of the first sealing region R1 and the second sealing region R2 will be described below. 10 and 11, the aspect ratio of the side joint portion 8 is changed from that in FIG. 3 for the sake of explanation.
For example, as shown in FIG. 10(A), from the inner end portion Sa on the inner side in the lateral direction Y of the seal portion S disposed on the innermost side in the lateral direction Y in the first seal region R1, it is placed on the outermost side in the lateral direction Y. The dimension D6 to the laterally Y outermost outer end Sb of the seal portion S thus formed is the laterally Y innermost inner end portion Sa of the laterally Y innermost seal portion S in the second seal region R2. to the laterally Y outermost outer end portion Sb of the seal portion S disposed most laterally Y outside.
In this case, the dimensions D6 and D7 can be adjusted, for example, by the number of seal rows SL and/or the dimension of the seal portion S in the lateral direction Y, or the like.

Further, for example, as shown in FIGS. 10A and 11A, the plurality of seal rows SL are arranged in the first seal region R1 and the second seal region R2, and the seal lines in the first seal region R1 are arranged. The number of rows is preferably less than the number of seal rows in the second seal region R2.
In FIGS. 10A and 11A, for example, two seal rows SL are arranged in the first seal region R1 and three seal rows SL are arranged in the second seal region R2.
As a result, the seal area ratio of the first seal region R1, which has a small number of seal rows, can be made smaller than the seal area ratio of the second seal region R2.

As another example, as shown in FIG. 10B, the average area of the plurality of seal portions S in the first seal region R1 may be smaller than the average area of the plurality of seal portions S in the second seal region R2. preferable.
This also makes it possible to make the seal area ratio of the first seal region R1, in which the average area of the plurality of seal portions S is small, smaller than the seal area ratio of the second seal region R2.

Further, for example, as shown in FIG. 11A, the plurality of seal rows SL are arranged in the first seal region R1 and the second seal region R2, and the lateral direction Y of the seal portion S in the first seal region R1 is preferably wider than the pitch D9 in the lateral direction Y of the plurality of seal rows SL in the second seal region R2.
As a result, the seal portions S in the first seal region R1 can be arranged more sparsely than the seal portions S in the second seal region R2. It can be smaller than the area ratio.

For example, as shown in FIG. 11B, the pitch D10 in the longitudinal direction X of the plurality of seal rows SL in the first sealing region R1 is equal to the pitch D11 in the longitudinal direction X of the plurality of seal rows SL in the second sealing region R2. is preferably wider than
This also allows the seal portions S in the first seal region R1 to be arranged more sparsely than the seal portions S in the second seal region R2, and the seal area ratio of the first seal region R1 to that of the second seal region R2. It can be smaller than the seal area ratio.

[Configuration example of the skin-side sheet in the first lamination part and the second lamination part]
From the viewpoint of adjusting the bonding strength between the first laminated portion T1 and the second laminated portion T2 and improving the tearing stability, the first skin side sheet P1 and the second skin side sheet P2 having different configurations may be adopted. good.

(Arrangement of embossed portions on skin-side sheet)
In the present embodiment, each of the first skin-side sheet P1 and the second skin-side sheet P2 may be made of a spunbond nonwoven fabric having a plurality of embossments.
The embossments of the spunbond nonwoven fabric are the portions where the fibers are crimped and fused. The embossing is, for example, intermittently formed by thermocompression bonding using an embossing convex roll and a flat roll, etc., formed by ultrasonic fusion, or formed by intermittently applying hot air to partially fuse. etc. From the viewpoint of high productivity and low equipment cost, the embossing is preferably formed by thermocompression bonding.
The planar shape of the embossing may take any shape such as circular, elliptical, polygonal, or similar shapes. The embossing is preferably formed in a regular pattern, but may be formed in a random pattern.
In the embossing, the fibers are likely to break due to heat treatment and/or processing during formation, so when the embossing overlaps with the embossing of the seal portion S, the seal strength may decrease.

Therefore, the first skin-side sheet P1 and the second skin-side sheet P2 have different embossed area ratios, that is, the ratio of the total area of the regions occupied by a plurality of embossings in the predetermined region to the total area of the predetermined region. It is preferably composed of a spunbond nonwoven fabric. Specifically, the first skin-side sheet P1 preferably has a higher embossed area ratio than the second skin-side sheet P2.
The embossed area ratio in the spunbond nonwoven fabric is measured in a region containing a sufficiently large number of embossments, and can be measured in a 20 mm×20 mm square region of the spunbond nonwoven fabric, for example. The area occupied by each embossment can be recognized as a series of areas where thermal fusion of the fibers is observed. In addition, the measurement of the above-mentioned area ratio shall be performed in the unfolded and stretched state.

As described above, the seal strength may be reduced in the seal portion S that overlaps the embossment. Therefore, by increasing the embossed area ratio in the first laminated portion T1 having a large number of laminated layers, the seal portion S and the embossed portions are more easily overlapped in the first laminated portion T1, and an increase in the seal strength can be suppressed. . As a result, the difference in joint strength between the first laminated portion T1 and the second laminated portion T2 can be reduced, and the joint strength of the entire side joint portion 8 can be further stabilized. Therefore, the tearing stability of the side joint portion 8 can be enhanced.

The embossed area ratio of the first skin side sheet P1 is preferably 5% or more, more preferably 7% or more, and preferably 20% or less, more preferably 17% or less.
The embossed area ratio of the second skin side sheet P2 is preferably 3% or more, more preferably 5% or more, and preferably 17% or less, more preferably 15% or less.

(melting point of skin side sheet)
As another example, the melting point of the first skin side sheet P1 is preferably higher than the melting point of the second skin side sheet P2.
The thermoplastic sheet 50 with a high melting point is less likely to be heat-sealed than the thermoplastic sheet 50 with a low melting point when the sealing process is performed under the same conditions, and the sealing strength tends to decrease. Therefore, by increasing the melting point of the first skin-side sheet P1 in the first laminated portion T1 having a large number of laminated layers, it is possible to suppress an increase in the seal strength of the seal portion S of the first laminated portion T1. As a result, the difference in joint strength between the first laminated portion T1 and the second laminated portion T2 can be reduced, and the joint strength of the entire side joint portion 8 can be further stabilized. Therefore, the ease of tearing the side joint portion 8 can be enhanced.

The melting point of the first skin side sheet P1 is preferably 125° C. or higher, more preferably 155° C. or higher, and preferably 260° C. or lower, more preferably 250° C. or lower.
The melting point of the second skin side sheet P2 is preferably 123° C. or higher, more preferably 125° C. or higher, and preferably 180° C. or lower, more preferably 170° C. or lower.

(Basis weight of skin side sheet)
As another example, the basis weight of the first skin-side sheet P1 is preferably lower than the basis weight of the second skin-side sheet P2.
In the thermoplastic sheet 50 with a high basis weight, the amount of thermoplastic resin is also large, and the seal strength of the seal portion S tends to be high. Therefore, in the first laminated portion T1 having a large number of laminated layers, by reducing the basis weight of the first skin-side sheet P1, it is possible to suppress an increase in the seal strength of the seal portion S of the first laminated portion T1. . As a result, the difference in joint strength between the first laminated portion T1 and the second laminated portion T2 can be reduced, and the joint strength of the entire side joint portion 8 can be further stabilized. Therefore, the tearing stability of the side joint portion 8 can be enhanced.

The basis weight of the first skin side sheet P1 is preferably 10 g/m ² or more, more preferably 12 g/m ² or more, and preferably 30 g/m ² or less, more preferably 25 g/m ² or less.
The basis weight of the second skin side sheet P2 is preferably 12 g/m ² or more, more preferably 14 g/m ² or more, and preferably 40 g/m ² or less, more preferably 30 g/m ² or less.

<Second embodiment>
Next, another embodiment will be described. In addition, in each of the following embodiments, the same reference numerals are given to the same or corresponding configurations as those of the above-described first embodiment, and the description thereof will be omitted as appropriate. In addition, the configuration described in the first embodiment can be applied to the pants-type absorbent article (underpants-type disposable diaper) of each embodiment to the extent possible.

In the first embodiment, the plurality of seal portions S are arranged in a grid pattern along the vertical direction X and the horizontal direction Y, but the present invention is not limited to this.
For example, as shown in FIG. 12, in two seal rows SL adjacent to each other in the lateral direction Y, the plurality of seal portions S of one seal row SL are aligned with the plurality of seal portions S of the other seal row SL in the longitudinal direction X. may be displaced from each other.
Also in this configuration, of the two seal portions S that belong to different seal rows SL and are adjacent to each other in the lateral direction Y, the seal portion S that is positioned on the inner side in the lateral direction Y is larger than the seal portion S that is positioned on the outer side in the lateral direction Y. It has low seal strength. As a result, it is possible to achieve both prevention of peeling during wearing and wearing, and ease of tearing during disposal.

As shown in FIG. 12, from the viewpoint of improving tearing stability, the pitch in the longitudinal direction X of the seal portions S of each seal row SL is constant in at least one of the waist end region 8c and the leg end region 8d. Preferably. In this configuration, it is preferable that the plurality of seal portions S have the same pitch in the longitudinal direction X in two seal rows SL adjacent to each other in the lateral direction Y. As shown in FIG. Further, the displacement in the vertical direction X between the seal portions S of one seal row SL and the seal portions S of the other seal row SL is more preferably 1/2 of the pitch.

<Third Embodiment>
In the above-described first embodiment, as the folding structure of the exterior body 5, a configuration in which only the outer layer sheet 51 is folded has been described, but the present invention is not limited to this.
In this embodiment, as shown in FIG. 13, both the outer layer sheet 51 and the inner layer sheet 52 may be folded.

In the example shown in FIG. 13, the outer layer sheet 51 and the inner layer sheet 52 are folded back from the waist opening end Wa toward the skin side. The leg-side ends of the outer layer sheet 51 and the inner layer sheet 52 in the folded region are arranged at substantially the same position in the longitudinal direction X. As shown in FIG.

Also in the pants-type absorbent article having the side joints 8 of the present embodiment, two seal portions belonging to different seal rows SL and adjacent to each other in the lateral direction Y are provided in at least one of the waist end region 8c and the leg end region 8d. Among S, the seal portion S located on the inner side in the lateral direction Y has a lower seal strength than the seal portion S located on the outer side in the lateral direction Y. As a result, it is possible to achieve both prevention of peeling during wearing and wearing, and ease of tearing during disposal.

Further, as in the first embodiment, the side joint portion 8 includes a first laminated portion T1 in which six or more thermoplastic sheets 50 including the first skin side sheet P1 are laminated, and a second skin side sheet P2. and a second laminated portion T2 in which thermoplastic sheets 50 are laminated in a number smaller than that of the first laminated portion T1. Also in the present embodiment, the first laminated portion T1 corresponds to a region where the exterior body 5 is folded back.

In the example shown in FIG. 13, the first laminated portion T1 of the ventral region 5a includes an outer layer sheet 51 that is not folded, an inner layer sheet 52 that is not folded, an inner layer sheet 52 that is folded, and an outer layer sheet that is folded. 51 and 4 layers. The first laminated portion T1 of the dorsal region 5b is also composed of the same four layers. Thus, the first laminated section T1 is composed of eight layers in total. In the first laminated portion T1, the first skin side sheet P1 is composed of the outer layer sheet 51 folded back.
In the example shown in FIG. 13, the second laminated portion T2 of the ventral region 5a is composed of two layers, an outer layer sheet 51 that is not folded back and an inner layer sheet 52 that is not folded back. The second laminated portion T2 of the dorsal region 5b is also composed of two similar layers. As a result, the second lamination part T2 is composed of a total of four layers. In the second laminated portion T2, the second skin side sheet P2 is composed of the inner layer sheet 52 that is not folded back.

Also in this configuration, similarly to the first embodiment, the ratio of the total area of the plurality of seal portions S to the total area of the first seal region R1 is calculated as follows: is preferably smaller than the ratio of the total area of In addition, the first skin-side sheet P1 and the second skin-side sheet P2 may be configured as described in the section "Configuration Example of the Skin-Side Sheets in the First Laminated Part and the Second Laminated Part" of the first embodiment. can. As a result, the joint strength of the entire side joint portion 8 can be further stabilized.

<Fourth Embodiment>
The configuration of the exterior body 5 having the folded structure is not limited to the above example. For example, the positions of the folded end portion 51a, which is the end portion of the folded region of the outer layer sheet 51, and the folded end portion 52a, which is the end portion of the folded region of the inner layer sheet 52, may differ in the longitudinal direction X. .
In the example shown in FIG. 14 , the folded end portion 52 a of the inner layer sheet 52 is positioned closer to the waist in the longitudinal direction X than the folded end portion 51 a of the outer layer sheet 51 . In the example shown in FIG. 14, both the outer layer sheet 51 and the inner layer sheet 52 are folded back in the waist end region 8c.

Also in this embodiment, the side joint portion 8 includes a first laminated portion T1 in which six or more thermoplastic sheets 50 including the first skin side sheet P1 are laminated, and a first laminated portion including the second skin side sheet P2. and a second laminated portion T2 in which thermoplastic sheets 50 are laminated in a number smaller than that of the portion T1. In this example, the first laminated portion T1 corresponds to a region where the exterior body 5 is folded.
Furthermore, in the present embodiment, the first laminated portion T1 includes regions in which the thermoplastic sheets 50 are laminated in different numbers. That is, the first laminated portion T1 includes a leg-side laminated portion T12 adjacent to the second laminated portion T2 and having more thermoplastic sheets 50 laminated than the second laminated portion T2, and a leg-side laminated portion T12 having more thermoplastic sheets 50 than the leg-side laminated portion T12. and a waist side laminated portion T11 in which a number of thermoplastic sheets 50 are laminated. For example, the waist end region 8c is included in the waist side laminated portion T11.

In the example shown in FIG. 14, the waist-side laminated portion T11 of the ventral region 5a includes an unfolded outer layer sheet 51, an unfolded inner layer sheet 52, a folded inner layer sheet 52, and a folded outer layer sheet. 51 and 4 layers. The waist-side laminated portion T11 of the back region 5b is also composed of the same four layers. Thus, the waist-side laminated portion T11 is composed of a total of eight layers.
In addition, the leg-side laminated portion T12 of the ventral region 5a is composed of three layers: an outer layer sheet 51 that is not folded back, an inner layer sheet 52 that is not folded back, and an outer layer sheet 51 that is folded back. The leg-side laminated portion T12 of the dorsal region 5b is also composed of the same three layers. Thus, the leg-side laminated portion T12 is composed of a total of six layers.
In both the waist-side laminated portion T11 and the leg-side laminated portion T12, the first skin-side sheet P1 is composed of the outer layer sheet 51 folded back.
In the example shown in FIG. 14, the second laminated portion T2 of the ventral region 5a is composed of two layers, an outer layer sheet 51 that is not folded back and an inner layer sheet 52 that is not folded back. The second laminated portion T2 of the dorsal region 5b is also composed of two similar layers. As a result, the second lamination part T2 is composed of a total of four layers. In the second laminated portion T2, the second skin side sheet P2 is composed of the inner layer sheet 52 that is not folded back.

Also in this configuration, similarly to the first embodiment, the ratio of the total area of the plurality of seal portions S to the total area of the first seal region R1 is calculated as follows: is preferably smaller than the ratio of the total area of Furthermore, in the first seal region R1, the ratio of the total area of the plurality of seal portions S to the total area of the waist-side laminated portion T11 is calculated as the total area of the plurality of seal portions S to the total area of the leg-side laminated portion T12. is preferably smaller than the ratio of
In addition, the first skin-side sheet P1 and the second skin-side sheet P2 may be configured as described in the section "Configuration example of the skin-side sheet in the first laminated portion and the second laminated portion" of the first embodiment. can. As a result, the joint strength of the entire side joint portion 8 can be further stabilized.

<Fifth Embodiment>
In the pants-type absorbent article of the present invention, the exterior body 5 may not have a folded structure.
In this embodiment, as shown in FIG. 15, both the outer layer sheet 51 and the inner layer sheet 52 may not be folded back, and the edges of these sheets may coincide with the waist opening edge Wa.
That is, in this example, the exterior body 5 as a whole is composed of the same number of laminations, and for example, the ventral region 5a and the dorsal region 5b are composed of two layers, the outer layer sheet 51 and the inner layer sheet 52, respectively. That is, in the entire side joint portion 8, the inner layer sheet 52 serves as the skin-side sheet P forming the skin-facing surface.

Moreover, in the present embodiment, the skin-side sheet P is preferably made of the same nonwoven fabric over the entire side joints 8 from the viewpoint of further stabilizing the joint strength in the entire side joints 8 .
For example, the skin-side sheet P is preferably composed of a spunbond nonwoven fabric including a plurality of embossments, and the distance between the embossments is preferably substantially constant throughout the side joints 8 . It should be noted that "the distance between embossments is substantially constant" means that when the shortest distance between 10 or more embossments is compared, the smallest distance is 100%, and the largest distance is 110% or less. means it fits.
For example, in the present embodiment, the melting point of the skin-side sheet P is preferably substantially constant throughout the side joint portion 8 . "The melting point of the skin side sheet P is substantially constant in the entire side joint portion 8" means that when the melting points of the skin side sheet P at 10 or more locations in the side joint portion 8 are compared, the lowest melting point is set to 100. %, the highest melting point is 110% or less.
For example, in the present embodiment, the basis weight of the skin-side sheet P is preferably substantially constant throughout the side joints 8 . "The basis weight of the skin-side sheet P is substantially constant over the entire side joint portion 8" means that the basis weight of the skin-side sheet P at 10 or more locations in the side joint portion 8 is the lowest basis weight. When the amount is 100%, it means that the highest basis weight falls within 110% or less.

<Sixth Embodiment>
Although the seal line SL is arranged in the waist end region 8c in the first embodiment, the seal line SL may be arranged in the leg end region 8d as shown in FIG. As a result, even when the wearer is lying down and the disposal person tears the side joint portion 8 from the leg end portion 8b, the ease of tearing described above can be realized.

Alternatively, as shown in FIG. 17, the seal line SL includes a waist end region 8c within 25 mm in the longitudinal direction X from the waist end 8a and a leg end region 8d within 25 mm in the longitudinal direction X from the leg end 8b. It may be a combined area. As a result, even when the disposal person tears the side joints 8 from either the waist end 8a or the leg end 8b, the ease of tearing described above can be realized.

<Other embodiments>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

In the present invention, since at least the relationship between the seal strengths of two adjacent seal portions S should satisfy the above relationship, the seal strengths of all the seal portions S in one seal row SL are It does not have to be lower than the seal strength of all the seal portions S of the seal row SL located.

In the above-described embodiment, the pair of side joints 8 have the same configuration, but only one side joint 8 may have the above-described plurality of seal rows SL.

For example, in the above-described embodiment, the outer body 5 has the ventral area 5a, the dorsal area 5b, and the crotch area 5c, but it is not limited to this. For example, the outer body 5 may have a configuration in which an abdominal region and a dorsal region are divided without having a crotch region.

The pants-type absorbent article according to the present invention does not have to be a disposable diaper for infants, and may be a disposable diaper for adults or children, for example. Furthermore, the pants-type absorbent article according to the present invention does not have to be a disposable diaper as long as it is an absorbent article of the type worn on the lower half of the body. Such pants-type absorbent articles include, for example, pants-type sanitary napkins.

Regarding the above-described embodiment, the present invention further discloses the following pants-type absorbent article.
<1>
a longitudinal direction extending from the abdomen of the wearer through the crotch to the dorsal side; and a lateral direction orthogonal to the longitudinal direction and corresponding to the lateral direction of the wearer;
An absorbent main body, and an outer covering composed of a plurality of laminated thermoplastic sheets, including an absorbent main body and a ventral region and a dorsal region disposed on the non-skin-facing side of the absorbent main body and positioned on both sides in the longitudinal direction. A pants-type absorbent article comprising a body and a pair of side joints that join the ventral region and the dorsal region of the outer body at the lateral side edges,
The pair of side joints are
a waist edge region within 25 mm in the longitudinal direction from the waist edge, which is the waist-side edge in the longitudinal direction;
a leg end region within 25 mm in the longitudinal direction from the leg end, which is the leg-side end in the longitudinal direction;
At least one of the pair of side joints,
a plurality of seal rows arranged in at least one of the waist end region and the leg end region along the transverse direction, each of which is composed of a plurality of seal portions spaced apart and aligned along the longitudinal direction; have
Of the two laterally adjacent seal portions belonging to different seal rows, the laterally inner seal portion has a lower seal strength than the laterally outer seal portion. Goods.
<2>
Of the two seal portions belonging to different seal rows and adjacent to each other in the lateral direction, the seal portion located on the inner side in the lateral direction has a lower degree of melting of the fibers than the seal portion located on the outer side in the lateral direction <1> The pants-type absorbent article according to 1.
<3>
<1> or <, of two seal portions belonging to different seal rows and adjacent to each other in the lateral direction, the seal portion positioned on the inner side in the lateral direction is configured to be thicker than the seal portion positioned on the outer side in the lateral direction. 2>, the pants-type absorbent article.
<4>
Of the two seal portions that belong to different seal rows and are adjacent to each other in the lateral direction, the seal portion that is positioned on the inner side in the lateral direction has a smaller area than the seal portion that is positioned on the outer side in the lateral direction <1> to <3>, the underpants-type absorbent article.
<5>
When the outermost seal row in the lateral direction is the outer seal row, and the seal row adjacent to the outer seal row on the inner side in the lateral direction is the inner seal row,
The lateral distance between the laterally outer outer ends of the seal portions of the outer seal row and the laterally inner inner ends of the seal portions of the inner seal row is a first dimension. and
The outer seal row according to any one of <1> to <4>, wherein the plurality of seal portions are arranged in the longitudinal direction at intervals of a second dimension smaller than the first dimension. A pants-type absorbent article.
<6>
The underpants-type absorbent article according to any one of <1> to <5>, wherein the plurality of seal portions included in the plurality of seal rows are aligned along the lateral direction.
<7>
At least one of the waist end region and the leg end region including the plurality of seal rows is cut into a rectangular shape with a length of 10 mm in the vertical direction and a length including the full width of the side joint in the horizontal direction. A sample for measurement is formed, and the seal strength is measured by peeling the measurement sample from the inner side to the outer side in the lateral direction at a speed of 10 mm / min.
The underpants-type absorbent article according to any one of <1> to <6>, wherein a minimum strength between peak strengths corresponding to the plurality of seal rows is greater than 0N.
<8> three or more seal rows are arranged as the plurality of seal rows in at least one of the waist end region and the leg end region;
when the seal strength of at least one of the waist end region and the leg end region including the three or more seal rows is measured, three or more peak strengths corresponding to the three or more seal rows are measured;
The underpants-type absorbent article according to <7>, wherein the minimum intensity between the three or more peak intensities increases in the order measured from the inner side to the outer side in the lateral direction.
<9>
When the outermost seal row in the lateral direction is the outer seal row, and the seal row adjacent to the outer seal row on the inner side in the lateral direction is the inner seal row,
The ratio of the lateral dimension of the seal portion of the inner seal row to the lateral distance between the seal portion of the outer seal row and the seal portion of the inner seal row is preferably 0.2. The pants-type absorbent article according to any one of <1> to <8>, and more preferably 0.3 or more.
<10>
The pants according to any one of <1> to <9>, wherein the interval between the seal portions of the laterally adjacent seal rows is configured to decrease from the inner side to the outer side in the lateral direction. type absorbent article.
<11>
The underpants-type absorbent article according to any one of <1> to <10>, wherein a pitch of the plurality of seal rows in the horizontal direction is 4 mm or more.
<12>
The underpants-type absorbent article according to any one of <1> to <11>, wherein a pitch of the plurality of seal portions in the vertical direction is 1.5 mm or more and 5.0 mm or less.
<13>
The ventral region and the dorsal region, respectively,
A plurality of elastic members extending in the lateral direction are arranged and have a first stretchable region and a second stretchable region extending in the lateral direction from one to the other of the pair of side joints,
the first elastic region extends in the lateral direction from the waist end region;
the second stretchable region is adjacent to the first stretchable region in the longitudinal direction and extends in the lateral direction from a region of the side joints excluding the waist end region;
According to any one of <1> to <12>, the average elongation rate of the plurality of elastic members in the first elastic region is lower than the average elongation rate of the plurality of elastic members in the second elastic region. A pants-type absorbent article.
<14>
the ventral region and the dorsal region each have a plurality of elastic members extending in the lateral direction from one of the pair of side joints to the other;
The pitch of the plurality of elastic members in the longitudinal direction at the side joint portion is larger than the pitch of the plurality of seal portions in the longitudinal direction, and is an integral multiple of the pitch of the plurality of seal portions in the longitudinal direction. The pants-type absorbent article according to any one of <1> to <13>.
<15>
The side joints are
a first sealing area and a second sealing area each including a plurality of sealing portions each having a regular planar shape and arrangement, extending across the entire width of the side joint portion in the lateral direction and adjacent to the longitudinal direction;
a first laminated portion in which six or more thermoplastic sheets are laminated and at least a portion of which is arranged in the first seal region;
a second laminated portion in which the thermoplastic sheets are laminated in a number smaller than that of the first laminated portion, and at least a portion of which is arranged in the second seal region;
At least one of planar shape or arrangement of the plurality of seal portions differs between the first seal region and the second seal region,
The ratio of the total area of the plurality of seal portions included in the first seal region to the entire area of the first seal region is the ratio of the total area of the plurality of seal portions included in the second seal region to the entire area of the second seal region. The pants-type absorbent article according to any one of <1> to <14>.
<16>
In the first seal region, from the laterally inner inner end portion of the seal portion that is disposed most laterally inward, the laterally outer side of the seal portion that is disposed most laterally outward The dimension to the end is the distance from the laterally inner inner end of the laterally innermost seal portion to the laterally outermost seal portion in the second seal region. The underpants-type absorbent article according to <15>, which is smaller than the dimension to the laterally outer outer end.
<17>
The plurality of seal rows are arranged in the first seal area and the second seal area,
The pants-type absorbent article according to <15> or <16>, wherein the number of seal rows in the first seal region is smaller than the number of seal rows in the second seal region.
<18>
The underpants type according to any one of <15> to <17>, wherein the average area of the plurality of seal portions in the first seal region is smaller than the average area of the plurality of seal portions in the second seal region absorbent article.
<19> Any one of <15> to <18>, wherein the pitch in the lateral direction of the seal portions in the first seal region is wider than the pitch in the lateral direction of the seal portions in the second seal region The pants-type absorbent article according to 1.
<20>
<19> according to any one of <15> to <19>, wherein the pitch in the longitudinal direction of the seal portions in the first seal region is wider than the pitch in the longitudinal direction of the seal portions in the second seal region A pants-type absorbent article.
<21>
The underpants-type absorbent article according to any one of <15> to <20>, wherein the first seal region extends from the first laminated portion to a part of the second laminated portion.
<22>
The side joints are
a first laminated portion in which six or more thermoplastic sheets including a first skin-side sheet constituting a skin-facing surface are laminated;
a second laminated portion including a second skin-side sheet forming a skin-facing surface and having a smaller number of thermoplastic sheets laminated than the first laminated portion;
The first skin-side sheet and the second skin-side sheet are each composed of a spunbond nonwoven fabric containing a plurality of embossments,
The underpants-type absorbent article according to any one of <1> to <21>, wherein the embossed area ratio of the first skin-side sheet is higher than the embossed area ratio of the second skin-side sheet.
<23>
The side joints are
a first laminated portion in which six or more thermoplastic sheets including a first skin-side sheet constituting a skin-facing surface are laminated;
a second laminated portion including a second skin-side sheet that forms a skin-facing surface, and a second laminated portion in which a smaller number of the thermoplastic sheets than the first laminated portion are laminated;
The underpants-type absorbent article according to any one of <1> to <22>, wherein the melting point of the first skin-side sheet is higher than the melting point of the second skin-side sheet.
<24>
The side joints are
a first laminated portion in which six or more thermoplastic sheets including a first skin-side sheet constituting a skin-facing surface are laminated;
a second laminated portion including a second skin-side sheet that forms a skin-facing surface, and a second laminated portion in which a smaller number of the thermoplastic sheets than the first laminated portion are laminated;
The pants-type absorbent article according to any one of <1> to <23>, wherein the basis weight of the first skin-side sheet is lower than the basis weight of the second skin-side sheet.

1 … Pants-type absorbent article (disposable diaper, diaper)
4 Absorbent body 5 Exterior body 5a Abdominal region 5b Back region 50 Thermoplastic sheet 8 Side joint 8a Waist end 8b Leg end 8c Waist end region 8d Leg end Area S... Seal part SL... Seal row

According to the underpants-type absorbent article of the present invention, it is possible to achieve both prevention of peeling during wearing and wearing, and ease of tearing during disposal.

Claims

a longitudinal direction extending from the abdomen of the wearer through the crotch to the dorsal side; and a lateral direction orthogonal to the longitudinal direction and corresponding to the lateral direction of the wearer;
An absorbent main body, and an outer covering composed of a plurality of laminated thermoplastic sheets, including an absorbent main body and a ventral region and a dorsal region disposed on the non-skin-facing side of the absorbent main body and positioned on both sides in the longitudinal direction. A pants-type absorbent article comprising a body and a pair of side joints that join the ventral region and the dorsal region of the outer body at the lateral side edges,
The pair of side joints are
a waist edge region within 25 mm in the longitudinal direction from the waist edge, which is the waist-side edge in the longitudinal direction;
a leg end region within 25 mm in the longitudinal direction from the leg end, which is the leg-side end in the longitudinal direction;
At least one of the pair of side joints,
a plurality of seal rows arranged in at least one of the waist end region and the leg end region along the transverse direction, each of which is composed of a plurality of seal portions spaced apart and aligned along the longitudinal direction; have
Of the two laterally adjacent seal portions belonging to different seal rows, the laterally inner seal portion has a lower seal strength than the laterally outer seal portion. Goods.
1. Of the two seal portions belonging to different seal rows and adjacent to each other in the lateral direction, the seal portion located on the inner side in the lateral direction has a lower degree of melting of fibers than the seal portion located on the outer side in the lateral direction. The pants-type absorbent article according to 1.
3. Of the two seal portions belonging to different seal rows and adjacent to each other in the lateral direction, the seal portion located on the inner side in the lateral direction is configured to be thicker than the seal portion located on the outer side in the lateral direction. The pants-type absorbent article according to 1.
4. Of the two seal portions belonging to different seal rows and adjacent to each other in the lateral direction, the seal portion located on the inner side in the lateral direction has a smaller area than the seal portion located on the outer side in the lateral direction. The pants-type absorbent article according to any one of .
When the outermost seal row in the lateral direction is the outer seal row, and the seal row adjacent to the outer seal row on the inner side in the lateral direction is the inner seal row,
The lateral distance between the laterally outer outer ends of the seal portions of the outer seal row and the laterally inner inner ends of the seal portions of the inner seal row is a first dimension. and
The underpants type according to any one of claims 1 to 4, wherein in the row of outer seals, the plurality of seal portions are arranged in the longitudinal direction at intervals of a second dimension smaller than the first dimension. absorbent article.
The underpants-type absorbent article according to any one of claims 1 to 5, wherein the plurality of seal portions included in the plurality of seal rows are aligned along the lateral direction.
At least one of the waist end region and the leg end region including the plurality of seal rows is cut into a rectangular shape with a length of 10 mm in the vertical direction and a length including the full width of the side joint in the horizontal direction. A sample for measurement is formed, and the seal strength is measured by peeling the measurement sample from the inner side to the outer side in the lateral direction at a speed of 10 mm / min.
The pants-type absorbent article according to any one of claims 1 to 6, wherein the minimum strength between peak strengths corresponding to the plurality of seal rows is greater than 0N.
three or more seal rows are arranged as the plurality of seal rows in at least one of the waist end region and the leg end region;
when the seal strength of at least one of the waist end region and the leg end region including the three or more seal rows is measured, three or more peak strengths corresponding to the three or more seal rows are measured;
8. The pants-type absorbent article according to claim 7, wherein the minimum intensity between the three or more peak intensities increases in the order measured from the inner side to the outer side in the lateral direction.
When the outermost seal row in the lateral direction is the outer seal row, and the seal row adjacent to the outer seal row on the inner side in the lateral direction is the inner seal row,
The ratio of the lateral dimension of the seal portion of the inner seal row to the lateral distance between the seal portion of the outer seal row and the seal portion of the inner seal row is 0.2 or more. The pants-type absorbent article according to any one of claims 1 to 8.
10. The pants-type absorbent according to any one of claims 1 to 9, wherein the interval between the seal portions of the seal rows adjacent in the lateral direction is configured to decrease from the inner side to the outer side in the lateral direction. sexual goods.
The pants-type absorbent article according to any one of claims 1 to 10, wherein the pitch of the plurality of front seal rows in the lateral direction is 4 mm or more.
The underpants-type absorbent article according to any one of claims 1 to 11, wherein the pitch of the plurality of seal portions in the longitudinal direction is 1.5 mm or more and 5.0 mm or less.
The ventral region and the dorsal region, respectively,
A plurality of elastic members extending in the lateral direction are arranged and have a first stretchable region and a second stretchable region extending in the lateral direction from one to the other of the pair of side joints,
the first elastic region extends in the lateral direction from the waist end region;
the second stretchable region is adjacent to the first stretchable region in the longitudinal direction and extends in the lateral direction from a region of the side joints excluding the waist end region;
The underpants type according to any one of claims 1 to 12, wherein the average elongation rate of the plurality of elastic members in the first elastic region is lower than the average elongation rate of the plurality of elastic members in the second elastic region. absorbent article.
the ventral region and the dorsal region each have a plurality of elastic members extending in the lateral direction from one of the pair of side joints to the other;
The pitch of the plurality of elastic members in the longitudinal direction at the side joint portion is larger than the pitch of the plurality of seal portions in the longitudinal direction, and is an integral multiple of the pitch of the plurality of seal portions in the longitudinal direction. The pants-type absorbent article according to any one of claims 1 to 13.
The side joints are
a first sealing area and a second sealing area each including a plurality of sealing portions each having a regular planar shape and arrangement, extending across the entire width of the side joint portion in the lateral direction and adjacent to the longitudinal direction;
a first laminated portion in which six or more thermoplastic sheets are laminated and at least a portion of which is arranged in the first seal region;
a second laminated portion in which the thermoplastic sheets are laminated in a number smaller than that of the first laminated portion, and at least a portion of which is arranged in the second seal region;
At least one of planar shape or arrangement of the plurality of seal portions differs between the first seal region and the second seal region,
The ratio of the total area of the plurality of seal portions included in the first seal region to the entire area of the first seal region is the ratio of the total area of the plurality of seal portions included in the second seal region to the entire area of the second seal region. 15. The pants-type absorbent article according to any one of claims 1 to 14, which is smaller than the ratio of the total area of the seal portions.
In the first seal area, from the laterally inner inner end portion of the seal portion that is disposed most laterally inward, the laterally outer side of the seal portion that is disposed most laterally outward The dimension to the end is the distance from the laterally inner inner end of the laterally innermost seal portion to the laterally outermost seal portion in the second seal region. 16. The pants-type absorbent article according to claim 15, wherein the dimension is smaller than the dimension to the outer edge of the laterally outer side.
The plurality of seal rows are arranged in the first seal area and the second seal area,
The pants-type absorbent article according to claim 15 or 16, wherein the number of seal rows in the first seal area is smaller than the number of seal rows in the second seal area.
The pants-type absorbent according to any one of claims 15 to 17, wherein the average area of the plurality of seal portions in the first seal region is smaller than the average area of the plurality of seal portions in the second seal region. Goods.
The pants type according to any one of claims 15 to 18, wherein the pitch in the lateral direction of the seal portions of the first seal region is wider than the pitch in the lateral direction of the seal portions of the second seal region. absorbent article.
The pants type according to any one of claims 15 to 19, wherein the pitch in the lateral direction of the seal portions of the first seal region is wider than the pitch in the lateral direction of the seal portions of the second seal region. absorbent article.
21. The pants-type absorbent article according to any one of claims 15 to 20, wherein the first seal region extends from the first laminated portion to part of the second laminated portion.
The side joints are
a first laminated portion in which six or more thermoplastic sheets including a first skin-side sheet constituting a skin-facing surface are laminated;
a second laminated portion including a second skin-side sheet forming a skin-facing surface and having a smaller number of thermoplastic sheets laminated than the first laminated portion;
The first skin-side sheet and the second skin-side sheet are each composed of a spunbond nonwoven fabric containing a plurality of embossments,
The underpants-type absorbent article according to any one of claims 1 to 21, wherein the embossed area ratio of the first skin-side sheet is higher than the embossed area ratio of the second skin-side sheet.
The side joints are
a first laminated portion in which six or more thermoplastic sheets including a first skin-side sheet constituting a skin-facing surface are laminated;
a second laminated portion including a second skin-side sheet forming a skin-facing surface, and a second laminated portion in which a smaller number of the thermoplastic sheets than the first laminated portion are laminated;
The pants-type absorbent article according to any one of claims 1 to 22, wherein the melting point of the first skin-side sheet is higher than the melting point of the second skin-side sheet.
The side joints are
a first laminated portion in which six or more thermoplastic sheets including a first skin-side sheet constituting a skin-facing surface are laminated;
a second laminated portion including a second skin-side sheet forming a skin-facing surface, and a second laminated portion in which a smaller number of the thermoplastic sheets than the first laminated portion are laminated;
The pants-type absorbent article according to any one of claims 1 to 23, wherein the basis weight of the first skin-side sheet is lower than the basis weight of the second skin-side sheet.