JP7282752B2 - Pants-type absorbent article - Google Patents

Description

The present invention relates to pants-type absorbent articles.

Pants-type disposable diapers are known as pants-type absorbent articles. For example, Patent Document 1 discloses a pants-type disposable diaper 1 having an abdominal sheet member 2 , a back sheet member 3 , and an absorbent core 5 . The abdominal sheet member 2 and the dorsal sheet member 3 each include a thread-like elastic member 7 that can be stretched in the width direction, and the waist elastic member 7W is arranged above the upper end portion 5W of the absorbent core 5 so that the diaper can be worn. Prevents slippage.

JP 2013-13683 A

However, when an infant with a rounded abdomen wears the pants-type disposable diaper 1 of Patent Document 1, the waist elastic member 7W may excessively tighten the abdomen of the infant.

SUMMARY OF THE INVENTION The present invention has been made in view of the conventional problems described above, and an object of the present invention is to provide a pants-type absorbent article that fits softly to the abdomen of the wearer.

The main invention for achieving the above object is
having an up-down direction, a left-right direction, and a front-back direction,
Having an absorbent main body with an absorbent core and a pair of waist parts,
The waist portion includes a skin-side sheet portion, a non-skin-side sheet portion, and a plurality of thread rubbers that can be stretched in the left-right direction,
At least the ventral waistline portion of the pair of waistline portions has an upper side portion above the absorbent main body in the vertical direction and a core side portion overlapping the absorbent core in the front-rear direction,
The plurality of rubber threads are pants having a plurality of upper rubber threads intermittently arranged in the upper part in the vertical direction and a plurality of core side rubber threads intermittently arranged in the core side part in the vertical direction. A type absorbent article,
The average value of the pitches of the upper rubber threads adjacent in the vertical direction in the upper portion is smaller than the average value of the pitches of the core side rubber threads adjacent in the vertical direction in the core side portion,
The value obtained by dividing the magnitude of the force for extending the upper portion in the lateral direction by the unit length by the length of the upper portion in the vertical direction is the value that extends the core side portion in the lateral direction by the unit length. smaller than the value obtained by dividing the magnitude of the force by the vertical length of the core side portion,
The abdominal waist portion overlaps the absorbent main body in the front-rear direction and has an intermediate portion above the absorbent core in the vertical direction,
The plurality of thread rubbers have an intermediate thread rubber arranged in the intermediate portion,
The upper part has an upper sheet part closer to the skin than the skin-side sheet part,
In the front-rear direction,
The upper thread rubber is arranged on the skin side of the skin side sheet portion and on the non-skin side of the upper sheet portion,
The core-side rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion,
The intermediate thread rubber is
a rubber thread disposed on the skin side of the skin-side sheet portion and on the non-skin side of the upper sheet portion;
The rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion.
A pants-type absorbent article characterized by:
Other features of the present invention will become apparent from the description of the specification and accompanying drawings.

According to the present invention, the upper part has a smaller pitch between the rubber threads than the core part side, thereby making it easier to make surface contact with the wearer's skin, while the upper part has a smaller contractile force than the core part side. This makes it easier to reduce the risk of leaving traces of the rubber thread on the wearer's skin.

FIG. 1 is a perspective view of an underpants-type disposable diaper 1 (hereinafter "diaper"). FIG. 2 is a schematic plan view of the diaper 1 in the unfolded and stretched state, viewed from the side of the skin. FIG. 3 is an enlarged view of the ventral waist portion 20 in FIG. FIG. 4 is an enlarged view of the dorsal waist portion 30 in FIG. FIG. 5 is a schematic cross-sectional view taken along line AA in FIG. FIG. 6 is a schematic cross-sectional view taken along line BB in FIG. 7A and 7B are diagrams for explaining a joint portion of the ventral waist portion 20 in FIG. 3. FIG. FIG. 8 is a schematic diagram illustrating a cross section of a modification of the ventral waist portion 20. As shown in FIG. FIG. 9 is a schematic diagram illustrating a cross section of a modification of the ventral waist portion 20. As shown in FIG. FIG. 10 is a schematic diagram illustrating a cross section of a modification of the ventral waist portion 20. As shown in FIG. FIG. 11 is a perspective view of an underpants-type disposable diaper 1 (hereinafter referred to as "diaper"). FIG. 12 is a schematic plan view of the diaper 1 in the unfolded and stretched state, viewed from the side of the skin. 13 is an enlarged view of the ventral waist portion 20 in FIG. 12. FIG. FIG. 14 is an enlarged view of the dorsal waist portion 30 in FIG. FIG. 15 is a schematic cross-sectional view taken along the line AA in FIG. 13. FIG. FIG. 16 is a schematic cross-sectional view taken along line BB in FIG. 17A and 17B are diagrams for explaining a joint portion of the ventral waist portion 20 in FIG. 13. FIG. FIG. 18 is a schematic diagram illustrating a cross section of a modification of the ventral waist portion 20. As shown in FIG. FIG. 19 is a schematic diagram illustrating a cross section of a modification of the ventral waist portion 20. As shown in FIG. FIG. 20 is a schematic diagram illustrating a cross section of a modification of the ventral waist portion 20. As shown in FIG. FIG. 21 is a schematic diagram illustrating a cross section of a modification of the ventral waist portion 20. As shown in FIG. FIG. 22 is a schematic diagram illustrating a cross section of a modified example of the ventral waist portion 20. As shown in FIG.

At least the following matters will become apparent from the descriptions of this specification and the accompanying drawings.
It has a vertical direction, a horizontal direction, and a front-back direction, and has an absorbent main body provided with an absorbent core and a pair of waist portions, wherein the waist portion includes a skin-side sheet portion, a non-skin-side sheet portion, and the lateral direction. At least the ventral waistline portion of the pair of waistline portions is, in the vertical direction, an upper portion above the absorbent main body, the absorbent core, and the front-back direction. The plurality of upper thread rubbers are intermittently arranged in the vertical direction on the upper side portion, and the plurality of upper rubber threads are intermittently arranged on the core side portion in the vertical direction. A pants-type absorbent article having a plurality of core-side rubber threads, wherein the average value of the pitches of the upper thread rubbers adjacent in the vertical direction in the upper part is adjacent in the vertical direction in the core side part A value obtained by dividing the magnitude of a force that is smaller than the average value of the pitches of the core-side rubber threads and extends the upper portion by a unit length in the horizontal direction by the length of the upper portion in the vertical direction, The underpants-type absorbent article is characterized in that the magnitude of the force for extending the core side portion in the lateral direction by the unit length is smaller than the value obtained by dividing the length of the core side portion in the vertical direction.

According to such a pants-type absorbent article, the pitch of the thread rubbers in the upper part is made smaller than that in the core part side, thereby making it easier to come into contact with the wearer's skin on the surface. It is easy to reduce the possibility that the wearer's skin may be left with traces of the rubber thread due to the rubber thread on the upper side, which has a small contractile force.

It has a vertical direction, a horizontal direction, and a front-back direction, and has an absorbent main body provided with an absorbent core and a pair of waist portions, wherein the waist portion includes a skin-side sheet portion, a non-skin-side sheet portion, and the lateral direction. At least the ventral waistline portion of the pair of waistline portions is, in the vertical direction, an upper portion above the absorbent main body, the absorbent core, and the front-back direction. The plurality of upper thread rubbers are intermittently arranged in the vertical direction on the upper side portion, and the plurality of upper rubber threads are intermittently arranged on the core side portion in the vertical direction. A pants-type absorbent article having a plurality of core-side rubber threads, wherein the average value of the pitches of the upper thread rubbers adjacent in the vertical direction in the upper part is adjacent in the vertical direction in the core side part A pants-type absorbent characterized in that the average value of the pitches of the core-side rubber threads is smaller than the average value of the pitches between the core-side rubber threads, and the average value of the diameters of the plurality of upper rubber threads is smaller than the average value of the diameters of the plurality of core-side rubber threads. It is a sexual item.

According to such a pants-type absorbent article, the pitch of the thread rubbers in the upper part is made smaller than that in the core part side, thereby making it easier to come into contact with the wearer's skin on the surface. It is easy to reduce the possibility that the wearer's skin may be left with traces of the rubber thread due to the upper rubber thread having a small diameter of the rubber thread.

In such a pants-type absorbent article, it is desirable that the plurality of upper thread rubbers are provided continuously from one end to the other end of the abdomen-side waistline portion in the left-right direction.

According to such a pants-type absorbent article, the upper thread rubber makes it easy to fit the abdominal waist portion from one end to the other end to the abdomen of the wearer.

In such a pants-type absorbent article, it is desirable that a cut portion is not provided at a central portion of the abdominal waistline portion in the left-right direction and at an upper end portion of the abdomen waistline portion in the vertical direction. .

According to such a pants-type absorbent article, if the upper end of the abdominal waist portion of the pants-type absorbent article is not cut, there is a risk that the upper rubber thread may leave marks on the wearer's skin. can be reduced.

In this underpants-type absorbent article, the ventral waist portion overlaps the absorbent main body in the front-rear direction and has an intermediate portion located above the absorbent core in the vertical direction. It is desirable that the rubber thread has an intermediate rubber thread arranged in the intermediate portion.

According to such a pants-type absorbent article, the intermediate thread rubber facilitates fitting the intermediate portion to the wearer's body.

In this pants-type absorbent article, the value obtained by dividing the magnitude of the force for extending the upper portion in the lateral direction by the unit length by the length of the upper portion in the vertical direction is obtained by dividing the intermediate portion by the length of the upper portion. It is preferable that the magnitude of the force for extending the length in the horizontal direction by a unit length is smaller than the value obtained by dividing the length of the intermediate portion in the vertical direction.

According to such a pants-type absorbent article, while the upper part is softly in contact with the wearer's skin, the intermediate part fits better to the wearer's skin, so that the upper end of the elastic thread is attached to the wearer's skin. It is possible to reduce the risk of excrement leaking from the absorbent main body while preventing marks from being left.

In such a pants-type absorbent article, the value obtained by dividing the magnitude of the force for extending the core side portion by the unit length in the lateral direction by the length of the upper portion in the vertical direction is the length of the intermediate portion. It is preferable that the size of the force for extending the horizontal direction by a unit length is smaller than the value obtained by dividing the length of the intermediate portion in the vertical direction.

According to such a pants-type absorbent article, by making the intermediate portion fit the wearer's skin more tightly than the core side portion, it is possible to further reduce the risk of excrement leaking from the upper side of the absorbent main body. can.

In such a pants-type absorbent article, the upper end portion of the non-skin side sheet portion has an upper sheet portion folded back toward the skin, and the lower end of the upper sheet portion is positioned higher than the upper end of the absorbent main body. It is desirable to be located on the lower side.

According to such a pants-type absorbent article, since the difference in rigidity between the upper end and the upper part of the absorbent body can be alleviated, the risk of bending in the vertical direction above the upper end of the absorbent body can be reduced. be able to.

In this pants-type absorbent article, the upper portion has an upper sheet portion closer to the skin than the skin-side sheet portion, and the upper thread rubber is closer to the skin than the skin-side sheet portion in the front-rear direction. and on the non-skin side of the upper sheet portion, and the core-side rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion. is desirable.

According to such a pants-type absorbent article, when the pants-type absorbent article is viewed from the non-skin side, the upper thread rubber of the waist portion becomes more difficult to see than the core-side rubber thread, and the upper portion of the wearer's body is visible. It makes it easier to give the impression of softly fitting the waist.

In such a pants-type absorbent article, it is desirable that the upper portion has a joining portion that joins the skin-side sheet portion and the non-skin-side sheet portion.

According to such a pants-type absorbent article, since the rigidity of the upper portion can be increased, it is possible to reduce the risk of the upper portion being rolled up in the vertical direction due to contraction of the rubber thread.

In such a pants-type absorbent article, the ventral waist portion has a joint portion that joins the skin-side sheet portion and the non-skin-side sheet portion, and the joint portion has a shape along the vertical direction. , and it is desirable that the plurality of joint portions be intermittently arranged in the left-right direction.

According to such a pants-type absorbent article, the rigidity in the vertical direction of the waist portion can be improved by the joint portion, so that the risk of the waist portion being loosened in the vertical direction due to the contraction of the rubber thread can be reduced. can be done.

In such a pants-type absorbent article, the back waist portion of the pair of waist portions includes, in the vertical direction, a back side upper portion overlapping with the upper portion and a back side core side overlapping with the core side portion. The plurality of rubber threads are arranged intermittently in the vertical direction on the upper back side portion and the upper back side thread rubber intermittently arranged in the vertical direction on the back side core side portion. having a plurality of back-side core-side rubber threads, and the magnitude of the force for extending the upper back-side portion by a unit length in the left-right direction is divided by the length of the upper back-side portion in the vertical direction. It is desirable that the value is larger than the value obtained by dividing the magnitude of the force for extending the dorsal core side portion by the unit length in the lateral direction by the length of the dorsal core side portion in the vertical direction.

According to such a pants-type absorbent article, the upper back thread rubber, which has a greater stretching force than the core-side thread rubber on the back side, tends to reduce the risk of the absorbent article falling down while worn. Become.

In this underpants-type absorbent article, the average value of the pitches of the vertically adjacent upper back thread rubbers in the upper back portion is the It is desirable that it is smaller than the average value of the pitch between the back side core side rubber threads.

According to such a pants-type absorbent article, the risk of the absorbent article falling down while worn is further reduced by the upper back thread rubber, which has a larger stretching force than the core-side thread rubber on the back side. easier.

In such a pants-type absorbent article, the back waist portion of the pair of waist portions includes, in the vertical direction, a back side upper portion overlapping with the upper portion and a back side core side overlapping with the core side portion. The plurality of rubber threads are arranged intermittently in the vertical direction on the upper back side portion and the upper back side thread rubber intermittently arranged in the vertical direction on the back side core side portion. The average value of the pitches of the upper thread rubbers adjacent in the vertical direction in the upper portion is the same as the spine adjacent in the vertical direction in the upper portion on the back side. The magnitude of the force that is equal to or less than the average value of the pitches of the upper side rubber threads and that extends the upper side portion by a unit length in the left-right direction extends the upper back side portion by a unit length in the left-right direction. It is desirable to be less than the magnitude of the force.

According to such a pants-type absorbent article, the rubber thread of the back waist portion makes it easy to fit the pants-type absorbent article around the wearer's waist, while the pitch of the rubber thread of the abdominal waist portion is adjusted to the back. By being equal to or less than the average value of the upper side part, the abdominal waist part, which is in contact with the skin of the upper part and has a small force for extending the rubber thread of the abdominal waist part, excessively tightens the wearer's abdomen. can be prevented.

===First embodiment===
Hereinafter, as an underpants-type absorbent article according to the present invention, a first embodiment will be described by taking a disposable diaper for infants as an example. However, the pants-type absorbent article according to the present invention can be used not only as a disposable diaper for infants but also as a disposable diaper for adults, sanitary shorts, and the like.

===Structure of Pants-type Disposable Diaper 1===
FIG. 1 is a perspective view of an underpants-type disposable diaper 1 (hereinafter "diaper"). FIG. 2 is a schematic plan view of the diaper 1 in the unfolded and stretched state, viewed from the side of the skin. The “unfolded state” means that the joint regions 2 of both sides of the underpants-type diaper 1 are separated from each other and opened. This is a state in which the entire diaper 1 is spread out in a plane. The term “stretched state” refers to a state in which the elastic members of the diaper 1 are stretched to such an extent that wrinkles of the diaper 1 are no longer visible. Specifically, it shows a state in which the dimensions of each member constituting the diaper 1 (for example, the ventral waist portion 20 to be described later, etc.) are stretched until they match or are close to the dimensions of the individual members. Line CC in FIG. 2 is the center line in the horizontal direction.

The diaper 1, in the underpants-type state shown in FIG. 1, has a vertical direction, a horizontal direction, and a front-rear direction, and is formed with a waist opening BH and a pair of leg openings LH. In the vertical direction, the waist opening BH side is the upper side, and the crotch side is the lower side. Further, the direction in which the materials forming the diaper 1 are laminated is called the thickness direction, the side in the thickness direction that contacts the wearer is called the skin side, and the opposite side is called the non-skin side. The front-rear direction of the diaper 1 in the underpants-type state corresponds to the thickness direction of the diaper 1 in the unfolded state.

The diaper 1 is a so-called three-piece type, and has an absorbent main body 10 , an abdominal waist portion 20 and a back waist portion 30 . The ventral waistline 20 covers the abdomen of the wearer and the dorsal waistline 30 covers the back of the wearer.

In the diaper 1 in the unfolded state shown in FIG. 2 , the abdominal waist portion 20 and the back waist portion 30 are arranged such that their longitudinal directions extend along the horizontal direction of the diaper 1 . Then, one longitudinal end of the absorbent main body 10 is joined to the central portion of the ventral waist portion 20 in the left-right direction with an adhesive portion H10 (FIG. 5) such as a hot-melt adhesive, so that the dorsal waist portion in the left-right direction is attached. The end of the absorbent main body 10 on the other longitudinal direction is joined to the central portion of 30 with an adhesive portion H10 (FIG. 5). Known patterns such as a stripe pattern, a spiral pattern, and an Ω pattern can be exemplified as the application pattern of the adhesive in the bonding portion H10. Moreover, the bonding between the abdominal waistline portion 20 and the back waistline portion 30 and the absorbent main body 10 is not limited to the adhesive, and may be a welded region fixed by heat welding, ultrasonic welding, or the like.

The diaper 1 in the unfolded state shown in FIG. 2 has a symmetrical shape with respect to the center line CC. Further, the absorbent main body 10 is folded in half at substantially the longitudinal center C10 so that the longitudinal direction of the absorbent main body 10 is along the vertical direction of the diaper 1, and both side ends of the abdominal waist portion 20 in the horizontal direction of the diaper 1 are folded. and both side ends of the dorsal waist portion 30 are joined by heat welding, ultrasonic welding, or the like to form a pair of joint regions 2, thereby forming the pants-type diaper 1 shown in FIG. .

The absorbent main body 10 includes an absorbent body 11, a liquid-permeable top sheet 12 arranged on the skin side of the absorbent body 11, and a liquid-impermeable back sheet arranged on the non-skin side of the absorbent body 11. 13 and an exterior sheet 14 arranged on the non-skin side of the back sheet 13. - 特許庁

The absorbent body 11 has a substantially rectangular shape in plan view, and includes an absorbent core 11A that absorbs and retains excreted fluid such as urine, and a liquid-permeable core wrap sheet 11B that covers the absorbent core 11A. As the absorbent core 11A, liquid-absorbent fibers such as pulp containing a superabsorbent polymer (SAP) are molded into a predetermined shape, for example, a substantially hourglass shape in plan view. Examples of the core wrap sheet 11B include liquid-permeable sheets such as tissue paper and non-woven fabric.

Further, as shown in FIG. 2, leg elastic members 15 are provided on both sides of the absorbent main body 10 in the left-right direction, so that the diaper 1 fits around the wearer's legs. The leg elastic members 15 are fixed in a stretched state in the longitudinal direction of the absorbent main body 10, for example, between the exterior sheets 14 that are folded inward in the left-right direction to form two layers. Examples of the leg elastic members 15 include thread rubber and elastic sheets.

The ventral waist portion 20 and the back waist portion 30 each have a substantially rectangular shape. A cut portion is not provided at the upper end portion of the abdominal waist portion 20 at the central portion in the left-right direction of the abdomen waist portion 20 . The cut portion refers to, for example, a shape that is recessed downward from the upper end portion of the ventral waist portion 20 . Similarly, a cut portion is not provided at the center of the dorsal waist portion 30 in the left-right direction and the upper end portion of the ventral waist portion 20 . The ventral waist portion 20 includes a skin side sheet (skin side sheet portion) 21, a non-skin side sheet 22, and a plurality of thread rubbers 23. The back waist portion 30 includes the skin side sheet 31 and the non-skin side sheet. It has side sheets 32 and a plurality of rubber threads 33 . The skin-side sheets 21, 31 and the non-skin-side sheets 22, 32 are respectively joined with an adhesive such as hot melt. Details of the plurality of rubber threads 23 and 33 will be described later.

The non-skin-side sheets 22, 32 are arranged on the non-skin side of the skin-side sheets 21, 31. - 特許庁The skin-side sheets 21 , 31 and the non-skin-side sheets 22 , 32 are arranged on the non-skin side of the absorbent body 10 . The upper ends of the non-skin-side sheets 22, 32 form folded portions 22u, 32u, respectively, which are folded downward to improve touch and durability. The non-skin-side sheet 22 has a non-skin-side sheet portion 22n and a folded portion 22u.

The skin-side sheets 21, 31 and the non-skin-side sheets 22, 32 include SMS nonwoven fabrics (spunbond/meltblown/spunbond nonwoven fabrics), spunbond nonwoven fabrics, air-through nonwoven fabrics, plastic sheets, perforated plastic sheets, laminate sheets thereof, and the like. of non-stretchable sheets can be used.

In addition, the ventral waist portion 20 has a sheet member 24 on the skin side of the folded portion 22u. The sheet member 24 is joined to the absorbent main body 10 and the folded portion 22u at an adhesive portion H24 (see FIG. 5) so as to straddle the upper end of the abdominal side of the absorbent main body 10. As shown in FIG. Similarly, the back waist portion 30 has a sheet member 34 on the skin side of the folded portion 32u. The sheet member 34 is joined to the absorbent main body 10, the folded portion 32u and the skin-side sheet 31 with an adhesive H34 (see FIG. 6) so as to straddle the upper end of the absorbent main body 10 on the back side. The sheet members 24 and 34 are rectangular sheet members made of nonwoven fabric or the like. The sheet members 24, 34 prevent the vertical ends of the absorbent body 10 from coming into direct contact with the wearer's skin, and make the ventral waist part 20 and the back waist part 30 more pleasant to the touch when worn. can be made good. In addition, the sheet members 24 and 34 can strengthen the joint between the ventral waist portion 20 and the back waist portion 30 and the absorbent main body 10 .

===Regarding rubber threads 23 and 33===
FIG. 3 is an enlarged view of the ventral waist portion 20 in FIG. FIG. 4 is an enlarged view of the dorsal waist portion 30 in FIG. Between the skin side sheets 21, 31 and the non-skin side sheets 22, 32, the plurality of rubber threads 23, 33 are coated with an adhesive such as hot melt from the upper end to the lower end. are arranged side by side and fixed in an extended state in the left-right direction. Therefore, the ventral waist portion 20 and the back waist portion 30 are joined to each other and expand and contract in the left-right direction to fit the wearer's waist.

As shown in FIG. 3, the ventral waist portion 20 has, in order from the top, a ventral upper portion AU, a ventral intermediate portion AM, and a ventral core side portion AC. Specifically, the ventral upper part AU is a rectangular area of the ventral waist part 20 that is above the absorbent main body 10 in the vertical direction. The ventral core side portion AC is a rectangular region of the ventral waist portion 20 that overlaps the absorbent core 11A in the front-rear direction. The ventral intermediate portion AM is a rectangular area overlapping the absorbent main body 10 and above the absorbent core 11A.

As shown in FIG. 4, the dorsal waist portion 30 has an upper dorsal portion BU, an intermediate dorsal portion BM, and a dorsal core side portion BC in order from the top. Specifically, in the pants-type diaper 1, the region of the dorsal waist portion 30 that overlaps the ventral upper portion AU of the ventral waist portion 20 in the front-rear direction is the dorsal upper portion BU, which is the ventral waist portion. The region of the back waist portion 30 that overlaps the ventral middle portion AM of the ventral waist portion 20 in the front-back direction is the back middle portion BM, and the back waist portion overlaps the ventral core side portion AC of the ventral waist portion 20 in the front-back direction. Region 30 is the dorsal core side BC.

FIG. 5 is a schematic cross-sectional view taken along line AA in FIG. FIG. 6 is a schematic cross-sectional view taken along line BB in FIG. In FIGS. 5 and 6, the dimensions are appropriately changed so as to facilitate understanding of the structure in the thickness direction.

As shown in FIG. 5, the ventral waist portion 20 includes, in order from the skin side, a sheet member 24, a folded portion 22u, a skin-side rubber thread 23u, a skin-side sheet 21, a non-skin-side rubber thread 23c, and an adhesive portion (joint portion). ) H20, and a non-skin side sheet portion 22n. Of the rubber threads 23 of the abdominal waist portion 20, the abdominal upper side AU has an abdominal upper rubber thread 23t, the abdominal intermediate part AM has an abdominal intermediate rubber thread 23m, and the abdominal core side AC has an abdominal side. A core-side rubber thread 23d is arranged. Specifically, a plurality of skin-side rubber threads 23u are arranged as the abdomen-side upper rubber thread 23t, and a plurality of skin-side rubber threads 23u and a plurality of non-skin-side rubber threads 23c are arranged as the abdomen-side middle rubber thread 23m, A plurality of non-skin-side rubber threads 23c are arranged as the abdomen-side core-side rubber threads 23d.

As shown in FIG. 6, the back waist portion 30 includes, in order from the skin side, a sheet member 34, a folded portion 32u, a skin side sheet 31, rubber threads 33, and a non-skin side sheet portion 32n. Among the rubber threads 33 of the back waist part 30, the back upper part BU has a back upper rubber thread 33t, the back middle part BM has a back middle rubber thread 33m, and the back core side part BC has a back side. A core-side rubber thread 33d is arranged. The rubber threads 33 of the back waist part 30 do not have skin-side rubber threads like the abdominal waist part 20, and all the rubber threads 33 are attached to the non-skin-side rubber threads 23c of the abdomen waist part 20. placed in corresponding positions.

The folded portion 22u of the ventral waist portion 20 is also referred to as an "upper sheet portion 22s" provided closer to the skin than the skin-side rubber thread 23u. The lower end of the folded portion 22u is preferably located below the upper end of the absorbent main body 10. As shown in FIG. In other words, the folded portion 22u is preferably arranged not only in the upper ventral portion AU but also in the intermediate ventral portion AM. As a result, the difference in rigidity at the upper end of the absorbent main body 10 caused by the upper end portion of the absorbent main body 10 having relatively high rigidity can be alleviated, so that the upper end of the absorbent main body 10 is bent as a boundary. can reduce fear.

The skin-side rubber threads 23u are arranged on the skin side of the skin-side sheet 21 and on the non-skin side of the folded portion 22u in the front-rear direction, and the non-skin-side rubber threads 23c are arranged on the non-skin side of the skin-side sheet 21. side and closer to the skin than the non-skin side sheet portion 22n. That is, since the skin-side rubber thread 23u is closer to the skin than the skin-side sheet 21 and the non-skin-side rubber thread 23c is closer to the non-skin side than the skin-side sheet 21, the skin-side rubber thread 23u is closer to the non-skin-side rubber thread 23c. Located closer to the skin. In the upper abdominal portion AU, the skin-side sheet 21, the adhesive portion H20, and the non-skin-side sheet portion 22n are arranged on the non-skin side of the skin-side rubber thread 23u. As a result, when the diaper 1 in the pants-type state, particularly in the worn state, is viewed from the non-skin side, the skin-side rubber threads 23u are visible through more material than the non-skin-side rubber threads 23c. The skin-side rubber thread 23u of the abdomen-side upper part AU can be made less visible than the non-skin-side rubber thread 23c, and the waist of the wearer is not excessively tightened, giving the impression that the diaper 1 is softly fitted. It becomes easier to give Further, as shown in FIGS. 2 and 3, the skin-side rubber thread 23u and the non-skin-side rubber thread 23c, which are the intermediate rubber threads 23m, are continuous from one end to the other end of the ventral waist portion 20 in the left-right direction. The non-skin-side rubber thread 23c can be fitted to the wearer's skin from one end to the other end of the ventral waist part 20, and is more easily visible than the skin-side rubber thread 23u. As for the ventral core side portion AC, it is easy to give the impression that the contractile force of the non-skin side rubber thread 23c is acting more strongly.

Moreover, in the abdominal upper part AU, it is preferable that the skin-side sheet 21 and the non-skin-side sheet part 22n are adhered by an adhesive part H20 such as a hot-melt adhesive. The abdominal upper part AU may be lowered such that the upper end of the abdominal waist part 20 is wound due to the contraction of the skin-side rubber thread 23u. In this regard, the rigidity of the upper abdominal portion AU can be improved by the rigidity of the adhesive portion H20 by bonding the skin-side sheet 21 and the non-skin-side sheet portion 22n with an adhesive. It is possible to reduce the risk that the upper end portion of the ventral waist portion 20 will be turned up. Note that the bonding portion H20 is not necessarily limited to a bonding portion using an adhesive, and may be a bonding portion using heat welding, ultrasonic welding, or the like, for example.

As shown in FIG. 5, the average value of the pitches Pt between the ventral upper rubber threads 23t is smaller than the average value of the pitches Pd between the ventral core-side rubber threads 23d. The value (F1/H1) obtained by dividing the magnitude of the force F1 to extend the ventral upper side AU by the vertical length H1 of the ventral upper side AU is the force to extend the ventral core side AC by a unit length in the left-right direction. It is smaller than the value (F3/H3) obtained by dividing the size F3 by the vertical length H3 of the ventral core side portion AC (F1/H1<F3/H3).

Also, the average value of the diameters of the plurality of abdominal upper rubber threads 23t is smaller than the average value of the diameters of the plurality of abdominal core side rubber threads 23d. In layman's terms, the ventral upper rubber thread 23t is thinner than the ventral core side rubber thread 23d. Therefore, the contractile force of the ventral upper rubber thread 23t in the left-right direction is smaller than the contractile force of the ventral core-side rubber thread 23d in the lateral direction.

The pitch Pt between the upper abdominal rubber threads 23t is the length between the centers of the upper abdominal rubber threads 23t adjacent in the vertical direction. The pitch Pt between the abdomen-side upper rubber threads 23t is also the pitch between the skin-side rubber threads 23u. In this embodiment, the average value of the pitch Pt is 2.5 mm, and the pitch Pt is preferably 1.0 mm to 4.0 mm. The pitch Pd between the ventral core rubber threads 23d is the length between the centers of the vertically adjacent ventral core rubber threads 23c. The pitch Pd between the ventral core side rubber threads 23d is also the pitch of the non-skin side rubber threads 23c. In this embodiment, the average value of the pitch Pd is 7.0 mm, and the pitch Pd is preferably 5.0 mm to 10.0 mm. In the present embodiment, each pitch Pt and each pitch Pd are substantially equal intervals, but the present invention is not limited to this. Each pitch Pt, Pd can be set to any value. Moreover, although the ventral upper rubber thread 23t and the ventral core side rubber thread 23d have approximately the same thickness, they are not limited to this. The ventral upper rubber thread 23t and the ventral core side rubber thread 23d may each have an arbitrary thickness.

The force for stretching in the left-right direction, that is, the “elongation force” in the left-right direction is the “contraction force” in the left-right direction. Therefore, when the ventral upper part AU is stretched outward in the left-right direction with a predetermined force, the ventral upper part AU tends to contract inward in the left-right direction. The inward force in the left-right direction is the "contraction force". For example, the stretching force required to transform the diaper 1 in the natural state into the diaper 1 in the stretched state is equal to the contraction force that causes the diaper 1 in the stretched state to return to the diaper 1 in the natural state. Hereinafter, the term “contraction force” may be used instead of “extension force”. That is, the contractile force acting in the horizontal direction per vertical unit length in the ventral upper side portion AU is smaller than the contractile force acting in the horizontal direction per vertical unit length in the ventral core side portion AC. The same applies to the force for extending each part of the dorsal waist part 30 in the left-right direction.

By setting the average value of the pitches Pt between the abdominal upper rubber threads 23t to be smaller than the average value of the pitches Pd between the abdominal core rubber threads 23d, the upper abdominal part AU is worn more than the abdominal core side AC. Since it becomes easy to contact a wearer's skin with a surface, the possibility that the ventral upper rubber thread 23t will locally tighten the wearer's skin can be reduced.

However, in general, the smaller the average value of the pitches Pt between the upper abdomen rubber threads 23t, the greater the number of the upper abdomen rubber threads 23t and the greater the contractile force of the upper abdomen part AU. Tend. In particular, since infants have a rounded abdomen, they are easily affected by contraction of the ventral upper rubber thread 23t. Further, if the contractile force of the entire abdominal waist portion 20 is reduced, the diaper 1 during wearing may not fit the abdomen of the wearer and may fall downward.

In this regard, in the diaper 1, the contractile force acting in the horizontal direction per vertical unit length in the upper abdomen portion AU is replaced by the contractile force acting in the horizontal direction per unit length in the vertical direction in the abdominal core side portion AC. making it smaller. The ventral upper part AU, which has a smaller contractile force, makes a softer contact with the wearer's abdomen. As a result, it is possible to reduce the possibility that the abdomen of the wearer is excessively tightened due to the contraction of the upper abdomen-side rubber thread 23t and that the wearer's skin is left with marks of the upper abdomen-side rubber thread 23t. On the other hand, the ventral core side portion AC, which has a greater contractile force, fits more strongly around the wearer's waist, reducing the risk of the diaper 1 falling downward, and allowing the absorbent core 11A to adhere to the wearer's skin. Since the contact is made to be stronger, it is possible to reduce the risk of leakage of excrement.

Moreover, it is preferable that the intermediate thread rubber 23m is also arranged in the ventral intermediate portion AM. The contraction of the intermediate thread rubber 23m facilitates fitting the absorbent main body 10 to the abdomen of the wearer. Furthermore, as shown in FIG. 5, the abdominal intermediate portion AM includes a skin-side rubber thread 23u and a non-skin-side rubber thread 23c as the intermediate rubber thread 23m, so that the absorbent main body 10 can fit the wearer's abdomen more. easier. Since the ventral intermediate portion AM is the ventral upper end portion of the absorbent main body 10, the ventral upper end portion of the absorbent main body 10 is brought into tighter contact with the wearer's skin, and the ventral upper end portion of the absorbent main body 10 is attached to the wearer's skin. It is possible to further reduce the risk of excrement leaking from the upper end.

The value (F1/H1) obtained by dividing the magnitude of the force F1 that stretches the ventral upper AU by a unit length in the left-right direction by the vertical length H1 of the ventral upper AU is the ventral intermediate AM. It is preferably smaller than the value (F2/H2) obtained by dividing the size F2 of horizontal extension by a unit length by the vertical length H2 of the ventral intermediate portion AM (F1/H1<F2/H2). As a result, the ventral middle rubber thread 23m fits the absorbent main body 10 to the abdomen of the wearer and prevents excrement from leaking, while the ventral upper part AU, which has a smaller contractile force than the ventral middle part AM, Since it comes into contact with the wearer's skin more softly, it is possible to reduce the possibility that the abdomen of the wearer is excessively tightened and marks are left on the ventral upper rubber thread 23t.

Furthermore, the value (F3/H3) obtained by dividing the magnitude of force F3 for extending the ventral core side AC by a unit length in the horizontal direction by the length H3 of the ventral core side AC in the vertical direction is It is preferable that the value (F2/H2) obtained by dividing the size F2 for extending the intermediate portion AM in the horizontal direction by a unit length by the length H2 of the ventral intermediate portion AM in the vertical direction (F3/H3<F2/ H2). That is, the lateral contraction force per vertical unit length in the ventral core side portion AC should be smaller than the lateral contraction force per vertical unit length in the ventral intermediate portion AM. This allows the absorbent body 10 to fit the wearer's skin more strongly than the ventral core side part AC in the ventral middle part AM. can be reduced.

The value (F4/H1) obtained by dividing the magnitude of the force F4 that extends the upper dorsal portion BU by a unit length in the horizontal direction by the length H1 of the upper dorsal portion BU in the vertical direction is the dorsal core side portion BC is preferably smaller than the value (F6/H3) obtained by dividing the force F6 by the length H3 in the vertical direction of the dorsal core side portion BC (F4/H1<F6/ H3). Since the dorsal upper part BU overlaps the ventral upper part AU, which has a vertical length H1, in the front-rear direction, the dorsal upper part BU has a vertical length H1, and the dorsal core side part Since the BC overlaps in the front-rear direction with the ventral core side portion AC having a vertical length of H3, the vertical length of the dorsal core side portion BC is H3. Furthermore, as shown in FIG. 6, the average value of the pitches Pj between the upper back rubber threads 33t is preferably smaller than the average value of the pitches Pk between the back core rubber threads 33d. That is, the upper back portion BU can fit the wearer's waist more firmly than when the contractile force of the upper back rubber thread 33t is smaller than the contractile force of the back core rubber thread 33d. It is possible to further reduce the risk of the diaper 1 falling down while being worn.

In addition, the average value of the pitches Pt between the abdominal upper rubber threads 23t is smaller than the average value of the pitches Pj between the dorsal upper rubber threads 33t, and the force for extending the abdominal upper part AU by the unit length in the left-right direction. It is more preferable that the magnitude F1 is equal to or less than the magnitude F4 of the force that stretches the upper dorsal portion BU by a unit length in the left-right direction (F1≦F4). As a result, in the pants-type diaper 1, the upper abdominal portion AU and the upper back portion BU, which forms a ring shape, come into contact with the wearer's skin more strongly than the core side portion BC. Therefore, in the upper end of the diaper 1, the upper abdomen portion AU softly abuts against the wearer's abdomen, which has a rounded shape, and the upper dorsal portion BU, which has a relatively flat shape, makes contact with the wearer's skin more strongly. It is possible to reduce the possibility that the diaper 1 will fall down due to contact.

The ventral waist portion 20 has a joint portion that joins the skin-side sheet 21 and the non-skin-side sheet 22, and in the diaper 1, it is the bonding portion H20. 7A and 7B are diagrams for explaining a joint portion of the ventral waist portion 20 in FIG. 3. FIG. In FIG. 7, the thread rubber 23 is omitted for convenience. As shown in FIG. 7, the plurality of bonding portions H20 each have a shape along the vertical direction and are intermittently arranged in the horizontal direction. An adhesive is continuously applied to the adhesive portion H20. Since the adhesive portion H20 has relatively high rigidity, it is possible to improve the rigidity in the vertical direction of the ventral waist portion 20, particularly the ventral upper portion AU. By improving the rigidity of the abdominal upper part AU, it is possible to further reduce the possibility that the upper end part of the abdominal waist part 20 is turned up. The bonding between the skin-side sheet 21 and the non-skin-side sheet 22 is not limited to bonding with an adhesive. For example, welding or fusing may be used. Also, the joint portion does not necessarily have to be continuous, and may be a plurality of welded portions or welded portions intermittently arranged in the vertical direction.

The magnitude of the force F1 that elongates the ventral upper part AU by a unit length in the lateral direction, the magnitude F2 that elongates the ventral intermediate part AM by a unit length in the lateral direction, and the ventral core side part AC in the lateral direction A magnitude of force F3 to elongate the dorsal upper part BU by a unit length, a force magnitude F4 to elongate the dorsal upper part BU by a unit length in the lateral direction, and a force of force F4 to elongate the dorsal core side part BC by a unit length in the lateral direction. An autograph type tensile tester (for example, AG-1KN1) manufactured by Shimadzu Corporation can be used to measure each contractile force of force magnitude F6.

First, the lateral length (elongation dimension) between the lateral inner sides of the joint regions 2 of the abdominal waistline portion 20 and the back waistline portion 30 of the diaper 1 in the stretched state is measured in advance. Then, the joints on both sides in the left-right direction of the diaper 1 including the joint region 2 are cut with a cutter, and the abdominal upper side portion AU, the abdominal intermediate portion AM, and the abdominal core side portion AC are cut from the abdominal waist portion 20 to the back. The dorsal upper part BU and the dorsal core side part BC are cut out from the side waist part 30 and used as samples.

When cutting out the upper ventral portion AU, the intermediate ventral portion AM, the ventral core side portion AC from the ventral waist portion 20, and the dorsal upper portion BU and the dorsal core side portion BC from the dorsal waist portion 30, Cut away together with the absorbent body 10 joined to the ventral waistline 20 and the back waistline 30 . For example, the abdominal intermediate portion AM sample is obtained by cutting the absorbent main body 10 that does not include the absorbent core 11A together with the abdominal waist portion 20, and the abdominal core side portion AC sample is the abdominal waist portion. Along with 20, the absorbent body 10 including the absorbent core 11A is cut away.

Next, one end of each sample is clamped between a fixed chuck and the other end between a movable chuck and stretched at a speed of 300 mm / min until it reaches a length of about 90% of the stretched dimension. The tensile load (N) when contracted to 75% of the size is obtained, and converted into a force (N/mm) per unit length (mm), which can be used as a force for extending the unit length.

The magnitude of the force that stretches each part (AU, AM, AC, BU, BM, BC) in the horizontal direction depends not only on the thickness of the rubber threads 23 and 33, but also on the spring constant of the rubber threads and the number of rubber threads. , can also be adjusted according to the type and number of materials laminated in each section (AU, AM, AC, BU, BM, BC).

=== Variation ===
8 to 10 are schematic diagrams illustrating cross sections of modifications of the ventral waist portion 20. FIG. In the above-described embodiment, the skin-side rubber thread 23u and the non-skin-side rubber thread 23c are arranged as the rubber thread 23 in the ventral waist portion 20, and the folded portion 22u is provided closer to the skin than the skin-side rubber thread 23u. It is not limited to this.

For example, as shown in FIGS. 8 and 9, only the non-skin-side rubber thread 23c may be arranged as the ventral-side intermediate rubber thread 23m, and the skin-side rubber thread 23u may not be arranged. Moreover, although not illustrated, only the skin side rubber thread 23u may be arranged as the abdominal side intermediate rubber thread 23m, and the non-skin side rubber thread 23c may not be arranged.

Further, as shown in FIG. 8, an upper sheet portion 22s made of a material different from that of the non-skin-side sheet 22 may be provided closer to the skin than the skin-side rubber thread 23u. The upper sheet portion 22s and the folded portion 22u need only cover at least the skin side rubber thread 23u from the skin side, and as shown in FIG. 8, the skin side rubber thread 23u is arranged in the abdominal upper region AU. Even in this case, the upper sheet portion 22s (folded portion u) may be provided over the abdominal upper portion AU and the abdominal intermediate portion AM. Similarly, the upper sheet portion 22s (folded portion u) may be provided over the abdominal upper portion AU, the abdominal intermediate portion AM, and the abdominal core side portion AC.

Furthermore, as shown in FIG. 9, the structure which does not arrange|position the skin side rubber thread 23u may be sufficient. Even in such a case, the average value of the pitches Pt between the abdominal upper rubber threads 23t is made smaller than the average value of the pitches Pd between the abdominal core side rubber threads 23d, so that the upper abdominal part AU is While making it easier to make contact with the skin, the contractile force acting in the horizontal direction per unit length in the vertical direction in the upper abdominal portion AU is applied in the horizontal direction per unit length in the vertical direction in the abdominal core side portion AC. By making it smaller than the working contractile force, it is possible to reduce excessive tightening in the ventral upper part AU. In addition, as shown in FIG. 9, in the abdominal upper part AU, by overlapping a plurality of members such as the skin side sheet 21 and the folded part 22u (upper sheet part 22s) on the skin side from the abdominal upper rubber thread 23t. , even if the abdominal upper thread rubber 23t contracts, the abdominal upper part AU can be made softer against the skin.

As shown in FIG. 10, not only the non-skin-side sheet 22 but also the skin-side sheet 21 may have a folded portion. By adopting such a configuration, it is possible to increase the amount of materials in the upper end portion of the ventral waist portion 20, so that contact with the skin due to contraction of the ventral upper rubber thread 23t can be further reduced, and It is possible to reduce the possibility that the thread rubber 23t excessively tightens the wearer's skin.

=== Second Embodiment ===
A second embodiment of the underpants-type absorbent article according to the present invention will now be described by taking a disposable diaper for infants as an example. However, the pants-type absorbent article according to the present invention can be used not only as a disposable diaper for infants but also as a disposable diaper for adults, sanitary shorts, and the like. In the following description, the skin side rubber thread 23u is also called "upper side rubber thread 23u", and the non-skin side rubber thread 23c is also called "core side rubber thread 23c".

===Structure of Pants-type Disposable Diaper 1===
FIG. 11 is a perspective view of an underpants-type disposable diaper 1 (hereinafter referred to as "diaper"). FIG. 112 is a schematic plan view of the diaper 1 in the unfolded state and the stretched state, viewed from the side of the skin. The “unfolded state” means that the joint regions 2 of both sides of the underpants-type diaper 1 are separated from each other and opened. This is a state in which the entire diaper 1 is spread out in a plane. The term “stretched state” refers to a state in which the elastic members of the diaper 1 are stretched to such an extent that wrinkles of the diaper 1 are no longer visible. Specifically, it shows a state in which the dimensions of each member constituting the diaper 1 (for example, the ventral waist portion 20 to be described later, etc.) are stretched until they match or are close to the dimensions of the individual members. Line CC in FIG. 12 is the center line in the horizontal direction.

The diaper 1, in the pants-type state shown in FIG. 11, has vertical, horizontal, and front-back directions, and is formed with a waist opening BH and a pair of leg openings LH. In the vertical direction, the waist opening BH side is the upper side, and the crotch side is the lower side. Further, the direction in which the materials forming the diaper 1 are laminated is called the thickness direction, the side in the thickness direction that contacts the wearer is called the skin side, and the opposite side is called the non-skin side. The front-rear direction of the diaper 1 in the underpants-type state corresponds to the thickness direction of the diaper 1 in the unfolded state.

The diaper 1 is a so-called three-piece type, and has an absorbent main body 10 , an abdominal waist portion 20 and a back waist portion 30 . The ventral waistline 20 covers the abdomen of the wearer and the dorsal waistline 30 covers the back of the wearer.

In the diaper 1 in the unfolded state shown in FIG. 12 , the abdominal waist portion 20 and the back waist portion 30 are arranged such that their longitudinal directions extend along the horizontal direction of the diaper 1 . Then, one longitudinal end of the absorbent body 10 is joined to the central portion of the ventral waist portion 20 in the left-right direction with an adhesive portion H10 (FIG. 15) such as a hot-melt adhesive, and the dorsal waist portion in the left-right direction. The end of the absorbent main body 10 on the other longitudinal direction is joined to the central portion of 30 with an adhesive portion H10 (FIG. 15). Known patterns such as a stripe pattern, a spiral pattern, and an Ω pattern can be exemplified as the application pattern of the adhesive in the bonding portion H10. Moreover, the bonding between the abdominal waistline portion 20 and the back waistline portion 30 and the absorbent main body 10 is not limited to the adhesive, and may be a welded region fixed by heat welding, ultrasonic welding, or the like.

The diaper 1 in the unfolded state shown in FIG. 12 has a symmetrical shape with respect to the center line CC. Further, the absorbent main body 10 is folded in half at substantially the longitudinal center C10 so that the longitudinal direction of the absorbent main body 10 is along the vertical direction of the diaper 1, and both side ends of the abdominal waist portion 20 in the horizontal direction of the diaper 1 are folded. 11 are joined to both side ends of the back waist portion 30 by heat welding, ultrasonic welding, or the like to form a pair of joint regions 2, thereby forming a pants-type diaper 1 shown in FIG. .

The absorbent main body 10 includes an absorbent body 11, a liquid-permeable top sheet 12 arranged on the skin side of the absorbent body 11, and a liquid-impermeable back sheet arranged on the non-skin side of the absorbent body 11. 13 and an exterior sheet 14 arranged on the non-skin side of the back sheet 13. - 特許庁

The absorbent body 11 has a substantially rectangular shape in plan view, and includes an absorbent core 11A that absorbs and retains excreted fluid such as urine, and a liquid-permeable core wrap sheet 11B that covers the absorbent core 11A. As the absorbent core 11A, liquid-absorbent fibers such as pulp containing a superabsorbent polymer (SAP) are molded into a predetermined shape, for example, a substantially hourglass shape in plan view. Examples of the core wrap sheet 11B include liquid-permeable sheets such as tissue paper and non-woven fabric.

Further, as shown in FIG. 12, leg elastic members 15 are provided on both sides of the absorbent main body 10 in the left-right direction, so that the diaper 1 fits around the wearer's legs. The leg elastic members 15 are fixed in a stretched state in the longitudinal direction of the absorbent main body 10, for example, between the exterior sheets 14 that are folded inward in the left-right direction to form two layers. Examples of the leg elastic members 15 include thread rubber and elastic sheets.

The ventral waist portion 20 includes a skin side sheet (skin side sheet portion) 21, a non-skin side sheet 22, and a plurality of thread rubbers 23. The back waist portion 30 includes the skin side sheet 31 and the non-skin side sheet. It has side sheets 32 and a plurality of rubber threads 33 . The skin-side sheets 21, 31 and the non-skin-side sheets 22, 32 are respectively joined with an adhesive such as hot melt. Details of the plurality of rubber threads 23 and 33 will be described later.

The non-skin-side sheets 22, 32 are arranged on the non-skin side of the skin-side sheets 21, 31. - 特許庁The skin-side sheets 21 , 31 and the non-skin-side sheets 22 , 32 are arranged on the non-skin side of the absorbent body 10 . The upper ends of the non-skin-side sheets 22, 32 form folded portions 22u, 32u, respectively, which are folded downward to improve touch and durability. The non-skin-side sheet 22 has a non-skin-side sheet portion 22n and a folded portion 22u.

The skin-side sheets 21, 31 and the non-skin-side sheets 22, 32 include SMS nonwoven fabrics (spunbond/meltblown/spunbond nonwoven fabrics), spunbond nonwoven fabrics, air-through nonwoven fabrics, plastic sheets, perforated plastic sheets, laminate sheets thereof, and the like. of non-stretchable sheets can be used.

In addition, the ventral waist portion 20 has a sheet member 24 on the skin side of the folded portion 22u. The sheet member 24 is joined to the absorbent main body 10 and the folded portion 22u at the adhesive portion H24 (see FIG. 15) so as to straddle the upper end of the abdominal side of the absorbent main body 10. As shown in FIG. Similarly, the back waist portion 30 has a sheet member 34 on the skin side of the folded portion 32u. The sheet member 34 is joined to the absorbent main body 10, the folded portion 32u and the skin-side sheet 31 with an adhesive H34 (see FIG. 16) so as to straddle the upper end of the absorbent main body 10 on the back side. The sheet members 24 and 34 are rectangular sheet members made of nonwoven fabric or the like. The sheet members 24, 34 prevent the vertical ends of the absorbent body 10 from coming into direct contact with the wearer's skin, and make the ventral waist part 20 and the back waist part 30 more pleasant to the touch when worn. can be made good. In addition, the sheet members 24 and 34 can strengthen the bonding between the front waistline portion 20 and the back waistline portion 30 and the absorbent main body 10 .

===Regarding rubber threads 23 and 33===
13 is an enlarged view of the ventral waist portion 20 in FIG. 12. FIG. FIG. 14 is an enlarged view of the dorsal waist portion 30 in FIG. Between the skin side sheets 21, 31 and the non-skin side sheets 22, 32, the plurality of rubber threads 23, 33 are coated with an adhesive such as hot melt from the upper end to the lower end. are arranged side by side and fixed in an extended state in the left-right direction. Therefore, the ventral waist portion 20 and the back waist portion 30 are joined to each other and expand and contract in the left-right direction to fit the wearer's waist.

As shown in FIG. 13 , the ventral waist portion 20 has, in order from the top, a ventral upper side portion AU, a ventral middle portion AM, and a ventral core side portion AC. Specifically, the ventral upper part AU is a rectangular area of the ventral waist part 20 that is above the absorbent main body 10 in the vertical direction. The ventral core side portion AC is a rectangular region of the ventral waist portion 20 that overlaps the absorbent core 11A in the front-rear direction. The ventral intermediate portion AM is a rectangular area overlapping the absorbent main body 10 and above the absorbent core 11A.

As shown in FIG. 14, the dorsal waist portion 30 has, in order from the top, a dorsal upper portion BU, a dorsal intermediate portion BM, and a dorsal core side portion BC. Specifically, in the pants-type diaper 1, the region of the dorsal waist portion 30 that overlaps the ventral upper portion AU of the ventral waist portion 20 in the front-rear direction is the dorsal upper portion BU, which is the ventral waist portion. The region of the back waist portion 30 that overlaps the ventral middle portion AM of the ventral waist portion 20 in the front-back direction is the back middle portion BM, and the back waist portion overlaps the ventral core side portion AC of the ventral waist portion 20 in the front-back direction. Region 30 is the dorsal core side BC.

FIG. 15 is a schematic cross-sectional view taken along the line AA in FIG. 13. FIG. FIG. 16 is a schematic cross-sectional view taken along line BB in FIG. In FIGS. 15 and 16, the dimensions are appropriately changed so as to facilitate understanding of the structure in the thickness direction.

As shown in FIG. 15, the ventral waist portion 20 includes, in order from the skin side, a sheet member 24, a folded portion 22u, an upper rubber thread 23u, a skin-side sheet 21, a core-side rubber thread 23c, and an adhesive portion (joint portion) H20. , and a non-skin side sheet portion 22n. Of the thread rubbers 23 of the ventral waist portion 20, upper thread rubbers 23u are disposed in the ventral upper portion AU and ventral intermediate portion AM, and cores are disposed in the ventral core side portion AC and ventral intermediate portion AM. A side thread rubber 23c is arranged. The upper rubber thread 23u and the core-side rubber thread 23c arranged in the ventral intermediate portion AM are also referred to as an intermediate rubber thread 23m. The folded portion 22u is also referred to as an "upper sheet portion 22s" provided closer to the skin than the upper rubber thread 23u.

As shown in FIG. 16, the back waist portion 30 includes, in order from the skin side, a sheet member 34, a folded portion 32u, a skin side sheet 31, rubber threads 33, and a non-skin side sheet portion 32n. The rubber thread 33 of the back waist portion 30 does not have the upper rubber thread like the abdominal waist portion 20. - 特許庁

The upper rubber thread 23u is arranged on the skin side of the skin-side sheet 21, on the non-skin side of the folded portion 22u, and on the non-skin side of the absorbent main body 10 in the front-rear direction. , on the non-skin side of the skin-side sheet 21, on the skin side of the non-skin-side sheet portion 22n, and on the non-skin side of the absorbent main body 10. - 特許庁That is, since the upper rubber thread 23u is closer to the skin than the skin-side sheet 21 and the core-side rubber thread 23c is closer to the skin than the skin-side sheet 21, the upper rubber thread 23u is closer to the skin than the core-side rubber thread 23c. positioned. In the upper abdomen portion AU, the skin side sheet 21, the adhesive portion H20, and the non-skin side sheet portion 22n are arranged on the non-skin side of the upper rubber thread 23u. Further, as shown in FIGS. 12 and 13, the upper rubber thread 23u and the core-side rubber thread 23c, which are the intermediate rubber thread 23m, are continuous from one end to the other end of the ventral waist portion 20 in the left-right direction. is provided.

By arranging the upper rubber thread 23u and the core-side rubber thread 23c in such a manner, when the diaper 1 in the pants-type state, particularly in the worn state, is viewed from the non-skin side, the upper rubber thread 23u is aligned with the core-side rubber thread. Since it will be visually recognized through more materials than 23c, the upper rubber thread 23u of the ventral upper part AU can be made more difficult to be visually recognized than the core-side rubber thread 23c.

The rubber thread of the waist portion of a conventional underpants-type disposable diaper is generally arranged between the skin-side sheet and the non-skin-side sheet like the back waist portion 30 . However, in the conventional underpants-type disposable diaper, the upper end of the waist portion, which does not have a portion overlapping the absorbent body in the vertical direction, is likely to be visually recognized as if the contractile force of the rubber thread is strongly acting, and the diaper 1 is easily removed. When viewed from the non-skin side, there is a risk of giving the impression that the upper end of the waist portion is excessively tightened. In particular, in the case of a body type in which the abdomen protrudes forward, such as an infant, there is a problem that it tends to give the impression that the abdomen is excessively tightened.

In this regard, in the diaper 1 of the present embodiment, the upper rubber thread 23u of the upper abdominal portion AU is made less visible than the core-side rubber thread 23c, so that the wearer's waist is not excessively tightened and the diaper 1 is soft. It makes it easier to give the impression that it fits. In addition, by having the core-side rubber thread 23c that is easier to see than the upper rubber thread 23u, the abdomen-side upper part AU gives the impression that it fits the wearer's abdomen softly, while the ventral-side core side part AC , the impression that the contractile force of the core-side rubber thread 23c is acting more strongly is likely to be given. As a result, even if the diaper 1 fits softly around the waist of the wearer, the impression is that the absorbent core 11A is made to fit the wearer's body more strongly, thereby reducing the risk of leakage of excrement to the outside of the diaper 1. It becomes easier to give

Since the intermediate rubber thread 23m is arranged in the abdomen-side intermediate portion AM, the contraction of the intermediate rubber thread 23m facilitates fitting the absorbent main body 10 to the abdomen of the wearer. Furthermore, in the abdomen-side intermediate portion AM, by providing the intermediate rubber thread 23m of the upper rubber thread 23u and the core-side rubber thread 23c, it becomes easier to fit the absorbent body 10 to the wearer's abdomen. Since the abdominal intermediate portion AM is the upper end portion of the absorbent main body 10 on the abdominal side, the upper end portion of the abdominal side of the absorbent main body 10 is brought into tighter contact with the wearer's skin, so that excrement is absorbed by the absorbent main body 10 . It is possible to further reduce the risk of leakage from the upper end portion on the ventral side of the tube. In addition, by providing the intermediate rubber 23m continuously provided from one end portion to the other end portion in the left-right direction of the abdominal waist portion 20, the upper end portion of the abdominal side of the absorbent main body 10 is brought into closer contact with the wearer's skin. The absorbent main body 10 can be made to fit the wearer's body.

Moreover, in the abdominal upper part AU, it is preferable that the skin-side sheet 21 and the non-skin-side sheet part 22n are adhered by an adhesive part H20 such as a hot-melt adhesive. The upper abdominal portion AU may be lowered such that the upper end portion of the abdominal waist portion 20 is wound due to the contraction of the upper rubber thread 23u. In this regard, the rigidity of the upper abdominal portion AU can be improved by the rigidity of the adhesive portion H20 by bonding the skin-side sheet 21 and the non-skin-side sheet portion 22n with an adhesive. It is possible to reduce the risk that the upper end portion of the ventral waist portion 20 will be turned up. Note that the bonding portion H20 is not necessarily limited to a bonding portion using an adhesive, and may be a bonding portion using heat welding, ultrasonic welding, or the like, for example.

The ventral waist portion 20 has a joint portion that joins the skin-side sheet 21 and the non-skin-side sheet 22, and in the diaper 1, it is the bonding portion H20. 17A and 17B are diagrams for explaining a joint portion of the ventral waist portion 20 in FIG. 13. FIG. In FIG. 17, the thread rubber 23 is omitted for convenience. As shown in FIG. 17, the plurality of bonding portions H20 each have a shape along the vertical direction and are intermittently arranged in the horizontal direction. An adhesive is continuously applied to the adhesive portion H20. Since the adhesive portion H20 has relatively high rigidity, it is possible to improve the rigidity in the vertical direction of the ventral waist portion 20, particularly the ventral upper portion AU. By improving the rigidity of the abdominal upper part AU, it is possible to further reduce the possibility that the upper end part of the abdominal waist part 20 is turned up. Further, as shown in FIG. 17, by making the length of the bonding portion H20 in the left-right direction shorter than the distance between two adjacent bonding portions H20, the length of the bonding portion H20 in the left-right direction is adjacent to each other. Compared to the case where the distance between the two adhesive portions H20 is longer, the risk of the upper ventral portion AU becoming too hard due to the adhesive can be reduced. The bonding between the skin-side sheet 21 and the non-skin-side sheet 22 is not limited to bonding with an adhesive. For example, welding or fusing may be used. Also, the joint portion does not necessarily have to be continuous, and may be a plurality of welded portions or welded portions intermittently arranged in the vertical direction.

Furthermore, the lower end of the folded portion 22u is located below the upper end of the absorbent main body 10. As shown in FIG. That is, the folded portion 22u is arranged not only in the upper ventral portion AU but also in the intermediate ventral portion AM. As a result, the difference in rigidity at the upper end of the absorbent main body 10 caused by the upper end portion of the absorbent main body 10 having relatively high rigidity can be alleviated, so that the upper end of the absorbent main body 10 is bent as a boundary. can reduce fear.

The value (F1/H1) obtained by dividing the magnitude of the force F1 that stretches the ventral upper AU by a unit length in the left-right direction by the vertical length H1 of the ventral upper AU is the ventral intermediate AM. It is preferably smaller than the value (F2/H2) obtained by dividing the size F2 of horizontal extension by a unit length by the vertical length H2 of the ventral intermediate portion AM (F1/H1<F2/H2).

The force for extending in the left-right direction, that is, the "elongation force" in the left-right direction is the "contraction force" in the left-right direction. Therefore, when the ventral upper part AU is stretched outward in the left-right direction with a predetermined force, the ventral upper part AU tends to contract inward in the left-right direction. The inward force in the left-right direction is the "contraction force". For example, the stretching force required to transform the diaper 1 in the natural state into the diaper 1 in the stretched state is equal to the contraction force that causes the diaper 1 in the stretched state to return to the diaper 1 in the natural state. Hereinafter, the term “contraction force” may be used instead of “extension force”.

That is, the contractile force acting in the horizontal direction per vertical unit length in the upper ventral portion AU is made smaller than the contractile force acting in the horizontal direction per unit vertical length in the ventral intermediate portion AM. As a result, the upper abdomen portion AU can be brought into soft contact with the wearer's skin, while the abdomen intermediate portion AM can be made to fit the wearer's skin more strongly. In the ventral middle part AM, the absorbent main body 10 is brought into contact with the wearer's skin more strongly to reduce the risk of leakage of excrement. It is possible to reduce the risk of the rubber thread 23 leaving traces on the wearer's skin due to tightening.

Further, the value (F3/H3) obtained by dividing the magnitude of the force F3 for extending the ventral core side portion AC by the unit length in the horizontal direction by the length H3 of the ventral core side portion AC in the vertical direction is It is preferable that the value (F2/H2) obtained by dividing the size F2 for extending the intermediate portion AM in the horizontal direction by a unit length by the length H2 of the ventral intermediate portion AM in the vertical direction (F3/H3<F2/ H2). That is, the lateral contraction force per vertical unit length in the ventral core side portion AC is made smaller than the lateral contraction force per vertical unit length in the ventral intermediate portion AM. This allows the absorbent body 10 to fit the wearer's skin more strongly than the ventral core side part AC in the ventral middle part AM. can be reduced.

Furthermore, the value (F1/H1) obtained by dividing the magnitude of the force F1 for extending the ventral upper AU by a unit length in the lateral direction by the vertical length H1 of the ventral upper AU is the ventral core side It is more preferable that the value (F3/H3) obtained by dividing the magnitude of force F3 for extending the portion AC in the horizontal direction by a unit length by the length H3 of the ventral core side portion AC in the vertical direction (F1/H1 <F3/H3). That is, the contractile force acting in the horizontal direction per vertical unit length in the ventral upper side portion AU can be made smaller than the contractile force acting in the horizontal direction per vertical direction unit length in the ventral core side portion AC. more preferred. As a result, in the abdominal upper part AU, the wearer's skin is excessively tightened, and the risk of leaving traces of the rubber thread 23 on the wearer's skin is reduced, while in the abdominal core side part AC Since the absorbent core 11A can be made to fit the wearer's skin more strongly, it is possible to further reduce the risk of leakage of excrement.

The magnitude of the force F1 that elongates the abdominal upper part AU by a unit length in the horizontal direction, the magnitude F2 that elongates the abdominal intermediate part AM by a unit length in the horizontal direction, and the abdominal core side part AC in the horizontal direction An autograph type tensile tester (for example, AG-1KN1) manufactured by Shimadzu Corporation can be used to measure the shrinkage force F3, which is the force that causes the film to be elongated by a unit length. First, the length in the left-right direction (elongation dimension) between the inner sides of the joint regions 2 of the abdominal waist portion 20 of the diaper 1 in the stretched state is measured in advance. The joints on both sides in the direction are cut with a cutter, and the ventral upper side portion AU, the ventral middle portion AM, and the ventral core side portion AC are cut out from the ventral waist portion 20 to obtain samples.

When cutting off the abdominal upper side portion AU, the abdominal intermediate portion AM, and the abdominal core side portion AC from the abdominal waist portion 20, they are cut together with the absorbent main body 10 joined to the abdominal waist portion 20. That is, the abdominal intermediate portion AM sample is obtained by cutting the absorbent main body 10 that does not include the absorbent core 11A together with the abdominal waist portion 20, and the abdominal core side portion AC sample is the abdominal waist portion. Along with 20, the absorbent body 10 including the absorbent core 11A is cut away.

Next, one end of each sample is clamped between a fixed chuck and the other end between a movable chuck and stretched at a speed of 300 mm / min until it reaches a length of about 90% of the stretched dimension. The tensile load (N) when contracted to 75% of the size is obtained, and converted into a force (N/mm) per unit length (mm), which can be used as a force for extending the unit length.

The magnitude of the force for extending each part (AU, AM, AC) in the horizontal direction can be adjusted by the thickness of the rubber thread, the spring constant of the rubber thread, the number of the rubber thread, or the like.

=== Variation ===
18 to 22 are schematic diagrams illustrating cross sections of modifications of the ventral waist portion 20. FIG. In the above-described embodiment, the upper rubber thread 23u is arranged in the abdominal upper part AU and the abdominal intermediate part AM, the core-side rubber thread 23c is arranged in the abdominal core side AC and the abdominal intermediate part AM, and the upper rubber thread Although the folded portion 22u is provided closer to the skin than the 23u, it is not limited to this.

For example, as shown in FIG. 18, the upper rubber thread 23u is arranged in the abdominal upper part AU, and the upper rubber thread 23u is not arranged in the abdominal intermediate part AM and the abdominal core side part AC. , the core-side rubber thread 23c may be arranged in the abdomen-side intermediate portion AM, and the core-side rubber thread 23c may not be arranged in the abdomen-side upper portion AU. Even in such a case, in the underpants-type diaper 1, the elastic thread 23 (23u) at the upper end of the abdomen-side waist portion 20 is made difficult to see, giving the impression that it is in soft contact with the abdomen of the wearer. In addition, the rubber thread 23 (23c) provided at a position overlapping the absorbent main body 10 in the front-rear direction allows the absorbent main body 10 to fit the wearer's body more strongly, thereby giving the impression that excrement is less likely to leak. can make it easier to give

Further, as shown in FIG. 19, an upper sheet portion 22s made of a material different from that of the non-skin side sheet 22 may be provided closer to the skin than the upper rubber thread 23u. Furthermore, the upper sheet portion 22s and the folded portion 22u are not necessarily arranged only in the region where the upper rubber thread 23u is arranged. The upper sheet portion 22s and the folded portion 22u need only cover at least the upper rubber thread 23u from the skin side, and as shown in FIG. , the upper sheet portion 22s (folded portion u) may be provided over the abdominal upper portion AU and the abdominal intermediate portion AM. Similarly, when the upper thread rubber 23u is arranged in the abdominal upper region AU, the upper sheet portion 22s (folded portion u) is formed into the abdominal upper portion AU, the abdominal intermediate portion AM, and the abdominal core side portion AC. It may be provided across.

As shown in FIG. 20, the upper rubber thread 23u may be arranged in the abdominal upper part AU and the abdominal intermediate part AM, and the core rubber thread 23c may be provided in the abdominal core side part AC. By doing so, in the underpants-type diaper 1, a larger number of upper rubber threads 23u, which are less visible from the non-skin side, are provided, so that the ventral waist portion 20 is soft and comes into contact with the wearer's skin. It becomes easier to give the impression that Alternatively, both the folded portion 22u and the upper sheet portion 22s may be provided.

As shown in FIG. 21, the upper thread rubber 23u may be arranged in the abdominal upper part AU, the abdominal intermediate part AM, and the abdominal core side part AC. Since more rubber threads can be arranged than in the conventional case where rubber threads are arranged between the skin-side sheet 21 and the non-skin-side sheet 22, the absorbent main body 10, particularly the absorbent core 11A can be It can be made to fit the wearer's skin better, and the risk of leakage of excrement can be reduced.

As shown in FIG. 22, not only the non-skin-side sheet 22 but also the skin-side sheet 21 may have a folded portion. With such a configuration, the rigidity of the upper end portion of the abdominal waist portion 20 can be improved, and the risk of the upper end portion of the abdominal waist portion 20 being turned up can be reduced.

The above-described embodiments of the present invention include pants-type absorbent articles of the following aspects, and solve the following problems.

Pants-type disposable diapers are known as pants-type absorbent articles. For example, Patent Document 1 discloses a pants-type disposable diaper 1 having an abdominal sheet member 2 , a back sheet member 3 , and an absorbent core 5 . The abdominal sheet member 2 and the dorsal sheet member 3 each have an elastic member 7 that can be stretched in the width direction, and the waist elastic member 7W is arranged above the upper end portion 5W of the absorbent core 5 to prevent the diaper from slipping off. prevent

However, in Patent Document 1, the waist elastic member 7W of the pants-type disposable diaper 1 in the worn state tends to be easily visible. Therefore, especially when the waist elastic member 7W is worn by an infant with a rounded abdomen, there is a risk that the waist elastic member 7W may give the impression that the waist of the wearer is excessively tightened.

The pants-type absorbent article of the following aspects has been made in view of the conventional problems as described above, and its purpose is to provide a pants-type absorbent article that tends to give the impression of being softly fitted around the waist of the wearer. The object of the present invention is to provide an article, and the above-described embodiment of the present invention also includes a pants-type absorbent article of the following aspects.

<Aspect 1>
having an up-down direction, a left-right direction, and a front-back direction,
Having an absorbent main body with an absorbent core and a pair of waist parts,
The waist portion includes a skin-side sheet portion, a non-skin-side sheet portion, and a plurality of thread rubbers that can be stretched in the left-right direction,
At least one of the pair of waistline portions has an upper side portion above the absorbent main body in the vertical direction and a core side portion overlapping the absorbent core in the front-rear direction,
The plurality of rubber threads in a pants-type absorbent article having an upper thread rubber arranged on the upper side and a core side rubber thread arranged on the core side,
The upper part has an upper sheet part closer to the skin than the skin-side sheet part,
In the front-rear direction,
The upper thread rubber is arranged on the skin side of the skin side sheet portion and on the non-skin side of the upper sheet portion,
The underpants-type absorbent article, wherein the core-side rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion.

According to the pants-type absorbent article of Aspect 1, when the pants-type absorbent article is viewed from the non-skin side, the upper thread rubber in the waist portion is less visible than the core-side rubber thread, and the upper portion is visible to the wearer. It makes it easier to give the impression of softly fitting the waist.

<Aspect 2>
The underpants-type absorbent article according to aspect 1, wherein the upper portion has a joint portion that joins the skin-side sheet portion and the non-skin-side sheet portion.

According to the pants-type absorbent article of Aspect 2, since the rigidity of the upper portion can be increased, it is possible to reduce the risk of the upper portion being rolled up in the vertical direction due to shrinkage of the rubber thread.

<Aspect 3>
The waist portion overlaps the absorbent main body in the front-rear direction and has an intermediate portion above the absorbent core in the vertical direction,
The underpants-type absorbent article according to mode 1 or 2, wherein the plurality of rubber threads have an intermediate rubber thread arranged in the intermediate portion.

According to the pants-type absorbent article of aspect 3, the intermediate thread rubber facilitates fitting the intermediate portion to the wearer's body.

<Aspect 4>
The underpants-type absorbent article according to aspect 3, wherein the intermediate rubber thread is arranged on the skin side of the skin-side sheet portion and on the non-skin side of the upper sheet portion.

According to such a pants-type absorbent article, when the pants-type absorbent article is viewed from the non-skin side, it is possible to make it difficult to visually recognize more rubber threads among the rubber threads provided in the waist portion. Therefore, it is easy to give an impression that the waist portion fits the wearer's waist softly.

<Aspect 5>
The underpants-type absorbent article according to mode 3, wherein the intermediate rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion.

According to the pants-type absorbent article of Aspect 5, since it becomes easy to visually recognize the rubber thread in the portion overlapping the absorbent main body in the front-back direction in the waist part, the absorbent main body fits the wearer's body, It becomes easy to give an impression that the excrement is hard to leak.

<Aspect 6>
The intermediate thread rubber is
a skin side from the skin side sheet portion and a non-skin side from the upper sheet portion;
6. The pants-type absorbent article according to any one of aspects 3 to 5, which are arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion, respectively.

According to the pants-type absorbent article of Aspect 6, the intermediate portion is provided with a rubber thread disposed closer to the skin than the skin-side sheet portion and a rubber thread disposed closer to the non-skin side than the skin-side sheet portion. Since the absorbent body can be fitted to the skin of the body, the risk of excrement leaking from the upper side of the absorbent body can be reduced.

<Aspect 7>
The value obtained by dividing the magnitude of the force for extending the upper portion in the horizontal direction by the unit length by the length of the upper portion in the vertical direction is the force for extending the intermediate portion by the unit length in the horizontal direction. 7. The pants-type absorbent article according to any one of aspects 3 to 6, wherein the size is smaller than the value obtained by dividing the size by the vertical length of the intermediate portion.

According to the pants-type absorbent article of Aspect 7, while the upper part is in soft contact with the wearer's skin, the intermediate part fits the wearer's skin better, so that the upper end part of the elastic thread is attached to the wearer's skin. It is possible to reduce the risk of excrement leaking from the absorbent main body while preventing marks from being left.

<Aspect 8>
The value obtained by dividing the magnitude of the force for extending the core side portion by the unit length in the lateral direction by the length of the core side portion in the vertical direction is the value obtained by extending the intermediate portion by the unit length in the lateral direction. 8. The underpants-type absorbent article according to any one of aspects 3 to 7, which is smaller than the value obtained by dividing the magnitude of the force applied by the length of the intermediate portion in the vertical direction.

According to the pants-type absorbent article of Aspect 8, by making the intermediate portion fit the wearer's skin more tightly than the core side portion, it is possible to further reduce the risk of excrement leaking from the upper side of the absorbent main body. can.

<Aspect 9>
The value obtained by dividing the magnitude of the force for extending the upper portion in the lateral direction by the unit length by the length of the upper portion in the vertical direction is the value that extends the core side portion in the lateral direction by the unit length. The pants-type absorbent article according to any one of aspects 3 to 8, wherein the force is smaller than the value obtained by dividing the magnitude of the force by the vertical length of the core side portion.

According to the pants-type absorbent article of Aspect 9, while the upper part is softly in contact with the wearer's skin, the core side part fits better to the wearer's skin, so that the upper end part is attached to the wearer's skin. It is possible to reduce the risk of excrement leaking from the absorbent core while preventing the presence of traces.

<Aspect 10>
The upper sheet portion is a portion in which the upper end portion of the non-skin side sheet portion is folded back toward the skin,
The pants-type absorbent article according to any one of aspects 1 to 9, wherein the lower end of the upper sheet portion is positioned below the upper end of the absorbent main body.

According to the pants-type absorbent article of aspect 10, the difference in rigidity at the upper end of the absorbent main body can be alleviated, so that the risk of bending at the upper end of the absorbent main body can be reduced.

<Aspect 11>
The one waist portion has a joint portion that joins the skin-side sheet portion and the non-skin-side sheet portion,
The joint portion has a shape along the vertical direction,
11. The underpants-type absorbent article according to any one of aspects 1 to 10, wherein the plurality of joints are intermittently arranged in the left-right direction.

According to the pants-type absorbent article of Aspect 11, since the joints can improve the rigidity of the waist in the vertical direction, it is possible to reduce the possibility that the waist will loosen in the vertical direction due to the contraction of the rubber thread. can be done.

Further, the above-described embodiments of the present invention also include pants-type absorbent articles of the following aspects.
<Aspect 12>
having an up-down direction, a left-right direction, and a front-back direction,
Having an absorbent main body with an absorbent core and a pair of waist parts,
The waist portion includes a skin-side sheet portion, a non-skin-side sheet portion, and a plurality of thread rubbers that can be stretched in the left-right direction,
At least one of the pair of waistline portions has an upper side portion above the absorbent main body in the vertical direction and a core side portion overlapping the absorbent core in the front-rear direction,
The plurality of rubber threads in a pants-type absorbent article having an upper thread rubber arranged on the upper side and a core side rubber thread arranged on the core side,
The upper part has an upper sheet part closer to the skin than the skin-side sheet part,
In the front-rear direction,
The upper thread rubber is arranged on the skin side of the skin side sheet portion and on the non-skin side of the upper sheet portion,
The core-side rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion,
The one waist portion overlaps the absorbent main body in the front-rear direction and has an intermediate portion above the absorbent core in the vertical direction,
The plurality of thread rubbers have an intermediate thread rubber arranged in the intermediate portion,
The underpants-type absorbent article, wherein the intermediate thread rubber is continuously provided from one end to the other end of the one waist portion in the left-right direction.

According to the pants-type absorbent article of Aspect 12, when the pants-type absorbent article is viewed from the non-skin side, the upper thread rubber in the waist portion is less visible than the core-side rubber thread, and the upper portion is visible to the wearer. It is easy to give the impression that the waist is softly fitted, and the intermediate thread rubber makes it easier to bring the intermediate part into close contact with the wearer's skin, so that the absorbent main body can be put in a state of being fitted to the wearer's body.

<Aspect 13>
The upper portion has a joint portion that joins the skin-side sheet portion and the non-skin-side sheet portion,
The underpants-type absorbent article according to aspect 12, wherein the joints extend along the vertical direction and are intermittently arranged in the horizontal direction.

According to the pants-type absorbent article of Aspect 13, since the joints can improve the rigidity of the waist in the vertical direction, it is possible to reduce the risk that the waist will loosen in the vertical direction due to the shrinkage of the rubber thread. can be done.

<Aspect 14>
The pants-type absorbent article according to aspect 13, wherein the length of the joint in the left-right direction is shorter than the distance between two adjacent joints.

According to the pants-type absorbent article of Aspect 14, there is a risk that the joints will make the upper part too hard compared to the case where the length of the joints in the left-right direction is longer than the distance between two adjacent joints. can be reduced.

<Aspect 15>
15. The underpants-type absorbent article according to any one of modes 12 to 14, wherein the intermediate rubber thread is arranged on the skin side of the skin-side sheet portion and on the non-skin side of the upper sheet portion.

According to the pants-type absorbent article of aspect 15, when the pants-type absorbent article is viewed from the non-skin side, it is possible to make it difficult to visually recognize more of the rubber threads among the rubber threads provided in the waist portion. Therefore, it is easy to give an impression that the waist portion fits the wearer's waist softly.

<Aspect 16>
15. The underpants-type absorbent article according to any one of modes 12 to 14, wherein the intermediate thread rubber is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion.

According to the pants-type absorbent article of Aspect 16, since it becomes easy to visually recognize the rubber thread in the portion of the waist area that overlaps the absorbent main body in the front-rear direction, the absorbent main body is fitted to the wearer's body, It becomes easy to give an impression that the excrement is hard to leak.

<Aspect 17>
The intermediate thread rubber is
a skin side from the skin side sheet portion and a non-skin side from the upper sheet portion;
15. The underpants-type absorbent article according to any one of aspects 12 to 14, which are arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion, respectively.

According to the pants-type absorbent article of Aspect 17, the intermediate portion is provided with a rubber thread disposed closer to the skin than the skin-side sheet portion and a rubber thread disposed closer to the non-skin side than the skin-side sheet portion. Since the absorbent body can be fitted to the skin of the body, the risk of excrement leaking from the upper side of the absorbent body can be reduced.

<Aspect 18>
The intermediate thread rubber is
a skin side of the skin-side sheet portion, a skin side of the upper sheet portion, and a non-skin side of the absorbent main body;
18. The pants-type absorbent according to any one of aspects 12 to 17, which are arranged on the non-skin side of the skin-side sheet portion and on the non-skin side of the non-skin-side sheet portion and the absorbent main body, respectively. Goods.

According to the pants-type absorbent article of Aspect 18, the intermediate portion is provided with a rubber thread disposed closer to the skin than the skin-side sheet portion and a rubber thread disposed closer to the non-skin side than the skin-side sheet portion. Since the absorbent body can be fitted to the skin of the body, the risk of excrement leaking from the upper side of the absorbent body can be reduced.

<Aspect 19>
The value obtained by dividing the magnitude of the force for extending the upper portion in the horizontal direction by the unit length by the length of the upper portion in the vertical direction is the force for extending the intermediate portion by the unit length in the horizontal direction. 19. The pants-type absorbent article according to any one of aspects 12 to 18, wherein the size is smaller than the value obtained by dividing the size by the vertical length of the intermediate portion.

According to the pants-type absorbent article of Aspect 19, while the upper part is softly in contact with the wearer's skin, the middle part fits better to the wearer's skin, so that the upper end part of the elastic thread is attached to the wearer's skin. It is possible to reduce the risk of excrement leaking from the absorbent main body while preventing marks from being left.

<Aspect 20>
The value obtained by dividing the magnitude of the force for extending the core side portion by the unit length in the lateral direction by the length of the core side portion in the vertical direction is the value obtained by extending the intermediate portion by the unit length in the lateral direction. 20. The underpants-type absorbent article according to any one of modes 12 to 19, which is smaller than the value obtained by dividing the magnitude of the force applied by the length of the intermediate portion in the vertical direction.

According to the pants-type absorbent article of Aspect 20, the intermediate portion fits the wearer's skin more tightly than the core side portion, thereby further reducing the risk of excrement leaking from the upper side of the absorbent main body. can.

<Aspect 21>
The value obtained by dividing the magnitude of the force for extending the upper portion in the lateral direction by the unit length by the length of the upper portion in the vertical direction is the value that extends the core side portion in the lateral direction by the unit length. 21. The pants-type absorbent article according to any one of aspects 12 to 20, wherein the force is smaller than the value obtained by dividing the magnitude of the force by the vertical length of the core side portion.

According to the pants-type absorbent article of Aspect 21, while the upper part is softly in contact with the wearer's skin, the core side part fits better to the wearer's skin, so that the upper end part is attached to the wearer's skin. It is possible to reduce the risk of excrement leaking from the absorbent core while preventing the presence of traces.

<Aspect 22>
The upper sheet portion is a portion in which the upper end portion of the non-skin side sheet portion is folded back toward the skin,
22. The pants-type absorbent article according to any one of aspects 12 to 21, wherein the lower end of the upper sheet portion is positioned below the upper end of the absorbent main body.

According to the pants-type absorbent article of Aspect 22, the difference in rigidity at the upper end of the absorbent main body can be alleviated, so that the risk of bending at the upper end of the absorbent main body can be reduced.

<Aspect 23>
The one waist portion has a joint portion that joins the skin-side sheet portion and the non-skin-side sheet portion,
The joint portion has a shape along the vertical direction,
23. The underpants-type absorbent article according to any one of aspects 12 to 22, wherein the plurality of joints are intermittently arranged in the left-right direction.

According to the pants-type absorbent article of Aspect 23, since the joints can improve the rigidity of the waist in the vertical direction, it is possible to reduce the possibility that the waist will loosen in the vertical direction due to the contraction of the rubber thread. can be done.

===Other Embodiments===
Although the embodiments of the present invention have been described above, the above-described embodiments are intended to facilitate understanding of the present invention, and are not intended to limit and interpret the present invention. Further, the present invention can be modified and improved without departing from its spirit, and it goes without saying that the present invention includes equivalents thereof.

In the above-described embodiment, the pants-type absorbent article has three members, namely, the abdominal waistline portion 20 and the back waistline portion 30, and the abdominal waistline portion 20, the back waistline portion 30, and the absorbent main body 10. Although a three-piece type diaper is exemplified, it is not limited to this. For example, the ventral waist portion 20 and the back waist portion 30 are formed as one continuous member via the crotch portion, and the exterior member in which the ventral waist portion 20 and the back waist portion 30 are integrated, and the absorption It may be a so-called two-piece type diaper having two members of the body.

In the above-described embodiment, the rubber thread of the abdominal waist portion 20 includes the upper rubber thread 23u and the core rubber thread 23c, while the back waist portion 30 has the skin side sheet 31 as in the configuration of a conventional disposable diaper. and the non-skin side sheet 32, but the present invention is not limited to this. The back waist part 30 may be configured to include the upper thread rubber and the core side rubber thread, or both the ventral waist part 20 and the back waist part 30 may be configured to include the upper thread rubber and the core side rubber thread. may be

1 diaper (pants-type absorbent article), 2 joint region,
10 absorbent body, 11 absorber,
11A absorbent core, 11B core wrap sheet,
12 top sheet, 13 back sheet,
14 exterior sheet, 15 leg elastic member,
20 ventral girth (girth),
21 skin-side sheet (skin-side sheet portion), 22 non-skin-side sheet (non-skin-side sheet portion),
22u folded portion, 22n non-skin side sheet portion, 22s upper sheet portion,
23 thread rubber,
23u skin side rubber thread (upper side rubber thread), 23c non-skin side rubber thread (core side rubber thread),
23t ventral upper thread rubber (upper thread rubber),
23m ventral intermediate thread rubber (intermediate thread rubber),
23d ventral core side rubber thread (core side rubber thread),
24 sheet member,
30 dorsal waist part (waist part),
31 skin side sheet, 32 non-skin side sheet,
32u folded portion, 32n non-skin side sheet portion,
33 thread rubber,
33t dorsal upper thread rubber, 33m dorsal middle thread rubber, 33d dorsal core side thread rubber,
34 sheet member,
AU ventral upper part (upper part),
AM ventral middle part (middle part),
AC ventral core side (core side),
BU dorsal upper part,
BM dorsal middle part,
BC dorsal core side,
H10 adhesion part,
H20 adhesion part (joint part),
H24 adhesion part,
H34 adhesion part

Claims (12)

having an up-down direction, a left-right direction, and a front-back direction,
Having an absorbent main body with an absorbent core and a pair of waist parts,
The waist portion includes a skin-side sheet portion, a non-skin-side sheet portion, and a plurality of thread rubbers that can be stretched in the left-right direction,
At least the ventral waistline portion of the pair of waistline portions has an upper side portion above the absorbent main body in the vertical direction and a core side portion overlapping the absorbent core in the front-rear direction,
The plurality of rubber threads are pants having a plurality of upper rubber threads intermittently arranged in the upper part in the vertical direction and a plurality of core side rubber threads intermittently arranged in the core side part in the vertical direction. A type absorbent article,
The average value of the pitches of the upper rubber threads adjacent in the vertical direction in the upper portion is smaller than the average value of the pitches of the core side rubber threads adjacent in the vertical direction in the core side portion,
The value obtained by dividing the magnitude of the force for extending the upper portion in the lateral direction by the unit length by the length of the upper portion in the vertical direction is the value that extends the core side portion in the lateral direction by the unit length. smaller than the value obtained by dividing the magnitude of the force by the vertical length of the core side portion,
The abdominal waist portion overlaps the absorbent main body in the front-rear direction and has an intermediate portion above the absorbent core in the vertical direction,
The plurality of thread rubbers have an intermediate thread rubber arranged in the intermediate portion,
The upper part has an upper sheet part closer to the skin than the skin-side sheet part,
In the front-rear direction,
The upper thread rubber is arranged on the skin side of the skin side sheet portion and on the non-skin side of the upper sheet portion,
The core-side rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion,
The intermediate thread rubber is
a rubber thread disposed on the skin side of the skin-side sheet portion and on the non-skin side of the upper sheet portion;
The rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion.
A pants-type absorbent article characterized by: having an up-down direction, a left-right direction, and a front-back direction,
Having an absorbent main body with an absorbent core and a pair of waist parts,
The waist portion includes a skin-side sheet portion, a non-skin-side sheet portion, and a plurality of thread rubbers that can be stretched in the left-right direction,
At least the ventral waistline portion of the pair of waistline portions has an upper side portion above the absorbent main body in the vertical direction and a core side portion overlapping the absorbent core in the front-rear direction,
The plurality of rubber threads are pants having a plurality of upper rubber threads intermittently arranged in the upper part in the vertical direction and a plurality of core side rubber threads intermittently arranged in the core side part in the vertical direction. A type absorbent article,
The average value of the pitches of the upper rubber threads adjacent in the vertical direction in the upper portion is smaller than the average value of the pitches of the core side rubber threads adjacent in the vertical direction in the core side portion,
The average value of the diameters of the plurality of upper rubber threads is smaller than the average value of the diameters of the plurality of core side rubber threads,
The abdominal waist portion overlaps the absorbent main body in the front-rear direction and has an intermediate portion above the absorbent core in the vertical direction,
The plurality of thread rubbers have an intermediate thread rubber arranged in the intermediate portion,
The upper part has an upper sheet part closer to the skin than the skin-side sheet part,
In the front-rear direction,
The upper thread rubber is arranged on the skin side of the skin side sheet portion and on the non-skin side of the upper sheet portion,
The core-side rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion,
The intermediate thread rubber is
a rubber thread disposed on the skin side of the skin-side sheet portion and on the non-skin side of the upper sheet portion;
The rubber thread is arranged on the non-skin side of the skin-side sheet portion and on the skin side of the non-skin-side sheet portion.
A pants-type absorbent article characterized by: The pants-type absorbent article according to claim 1 or 2,
The underpants-type absorbent article, wherein the plurality of upper thread rubbers are continuously provided from one end to the other end of the abdominal waist portion in the left-right direction. The pants-type absorbent article according to any one of claims 1 to 3,
A pants-type absorbent article, wherein a cut portion is not provided at a central portion of the abdominal waist portion in the left-right direction and at an upper end portion of the abdominal waist portion in the vertical direction. The pants-type absorbent article according to any one of claims 1 to 4 ,
The value obtained by dividing the magnitude of the force for extending the upper portion in the horizontal direction by the unit length by the length of the upper portion in the vertical direction is the force for extending the intermediate portion by the unit length in the horizontal direction. A pants-type absorbent article, wherein the size is smaller than the value obtained by dividing the size by the vertical length of the intermediate portion. The pants-type absorbent article according to any one of claims 1 to 5 ,
The value obtained by dividing the magnitude of the force for extending the core side portion by the unit length in the lateral direction by the length of the upper portion in the vertical direction is the value that extends the intermediate portion by the unit length in the lateral direction. A pants-type absorbent article, wherein the magnitude of the force is smaller than the value obtained by dividing the magnitude of the force by the vertical length of the intermediate portion. The pants-type absorbent article according to any one of claims 1 to 6 ,
The upper sheet portion is a folded portion in which an upper end portion of the non-skin side sheet portion is folded back toward the skin,
A pants-type absorbent article, wherein the lower end of the upper sheet portion is positioned below the upper end of the absorbent main body. The pants-type absorbent article according to any one of claims 1 to 7 ,
The underpants-type absorbent article, wherein the upper portion has a joining portion that joins the skin-side sheet portion and the non-skin-side sheet portion. The pants-type absorbent article according to any one of claims 1 to 8 ,
The ventral waist portion has a joint portion that joins the skin side sheet portion and the non-skin side sheet portion,
The joint portion has a shape along the vertical direction,
The underpants-type absorbent article, wherein the plurality of joints are intermittently arranged in the left-right direction. The pants-type absorbent article according to any one of claims 1 to 9 ,
The dorsal waist portion of the pair of waist portions has, in the vertical direction, a dorsal upper portion that overlaps with the upper portion and a dorsal core side portion that overlaps with the core side portion,
The plurality of thread rubbers are composed of a plurality of upper back thread rubbers intermittently arranged in the upper back portion in the vertical direction, and a plurality of upper back thread rubbers intermittently arranged in the vertical direction on the back core side portion. having a side core side thread rubber,
The value obtained by dividing the magnitude of the force for extending the dorsal upper portion by a unit length in the lateral direction by the length of the dorsal upper portion in the vertical direction is the value obtained by dividing the dorsal core side portion in the lateral direction A pants-type absorbent article, characterized in that it is greater than the value obtained by dividing the magnitude of force for stretching by a unit length by the vertical length of the dorsal core side portion. The pants-type absorbent article according to claim 10 ,
The average value of the pitches between the vertically adjacent back side upper rubber threads in the back side upper part is the pitch between the vertically adjacent back side core side rubber threads in the back side core side part. A pants-type absorbent article characterized by being smaller than the average value. The pants-type absorbent article according to any one of claims 1 to 11 ,
The dorsal waist portion of the pair of waist portions has, in the vertical direction, a dorsal upper portion that overlaps with the upper portion and a dorsal core side portion that overlaps with the core side portion,
The plurality of thread rubbers are composed of a plurality of upper back thread rubbers intermittently arranged in the upper back portion in the vertical direction, and a plurality of upper back thread rubbers intermittently arranged in the vertical direction on the back core side portion. having a side core side thread rubber,
The average value of the pitches of the upper rubber threads adjacent to each other in the vertical direction in the upper part is equal to or less than the average value of the pitches of the upper back rubber threads adjacent to each other in the upper back part,
A pants type characterized in that the magnitude of the force for extending the upper portion in the left-right direction by a unit length is equal to or less than the magnitude of the force for extending the upper back portion by the unit length in the left-right direction. absorbent article.

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