Patent Description:
As an underpants-shaped absorbent article, for example, PTL <NUM> discloses a pull-on disposable diaper including an absorbent main body and a tubular waist portion in which two lateral side edges of a front exterior sheet that covers the front side of a wearer are joined to two lateral side edges of a back exterior sheet that covers the back side of the wearer.

In the diaper of PTL <NUM>, the back exterior sheet includes a back extending portion extending on the lower side of the joint portion. The back extending portion includes a buttock-covering portion extending on two lateral outer sides of the absorbent main body. The buttock-covering portion is provided with a plurality of elastic members fixed extending in the lateral direction with an interval therebetween in the up-down direction. Thus, the wearer's buttocks can be covered with the buttock-covering portion. In addition, protrusion and turning-up of the buttock-covering portion can be avoided by the elastic members, and the buttock-covering portion can be caused to fit the wearer's buttocks. <CIT>, <CIT> and <CIT> disclose absorbent articles and/or methods relating to the same.

However, the width of the buttock-covering portion extending on one side of the absorbent main body is smaller than the width of the absorbent main body, and accordingly a target wearer of the diaper of PTL <NUM> is a child. In an adult diaper compared with a child diaper, it is necessary to increase the width of the buttock-covering portion. Incidentally, the degree of the curvature of the buttocks of an adult is large. Therefore, compared with a child diaper, it is difficult to cause the buttock-covering portion to fit a wearer. Accordingly, when the diaper of PTL <NUM> is employed for adult use, it is difficult for the laterally-extending elastic members alone to fit the buttock-covering portion to a wearer.

The present invention was achieved in light of conventional problems such as that described above, and an aspect of the present invention is to provide an underpants-shaped absorbent article that fits the wearer's buttocks.

A main aspect of the present invention for achieving the above-described aspect is defined in claim <NUM>.

According to the present invention, it is possible to provide an underpants-shaped absorbent article that fits the wearer's buttocks.

At least the following matters will become clear with the description of this specification and the attached drawings.

An underpants-shaped absorbent article having an up-down direction, a left-right direction, and a front-back direction,
the underpants-shaped absorbent article including:.

According to such an underpants-shaped absorbent article, due to the long length of the extending portion in the left-right direction and the wide area of the extending portion, it is possible to cover the wearer's buttocks even with large buttocks. In other words, a wide portion of the wearer's buttocks can be covered by the soft extending portion having low stiffness compared with the absorbent main body, and this improves comfort. In addition, due to the inclining elastic members causing the left-right-direction side end portions of the extending portion to fit along the outline of the wearer's buttocks, namely, due to the elastic members positioned on the outer side of an apex portion of the buttocks, it is possible for the extending portion to wrap the wearer's buttocks while the extending portion is not turned up even though the area of the extending portion is large. In particular, the stiffness of the left-right-direction side end portions of the extending portion increases due to an overlapping portion of the inclining elastic members and the lateral elastic members. This makes it easier to maintain a state in which the side end portions of the extending portion fit along the outline of the wearer's buttocks. This makes it less likely for the extending portion to turn up or displace even when the wearer moves. In addition, even when the area of the extending portion is large, the extending portion extends along the wearer's buttocks in close contact therewith without floating due to the lateral elastic members.

In such an underpants-shaped absorbent article, it is desirable that
the lateral elastic member extends outward in the left-right direction with respect to the inclining elastic member.

According to such an underpants-shaped absorbent article, the stiffness of the left-right-direction side end portions of the extending portion increases due to the overlapping portion of the inclining elastic members and the lateral elastic members. This makes it easier to maintain a state in which the side end portions of the extending portion fit along the outline of the wearer's buttocks. In addition, portions outside the inclining elastic members in the left-right direction contract due to the lateral elastic members, and thereby the left-right-direction side end portions of the extending portion are formed into a frill shape. Consequently, texture of the side end edge of the extending portion is improved. Moreover, it is also possible to provide a user with a visually soft impression.

In such an underpants-shaped absorbent article, it is desirable that
the lateral elastic member reaches a left-right-direction side end of the extending portion.

According to such an underpants-shaped absorbent article, a larger stretching force of the lateral elastic members is exerted on regions outside the inclining elastic members in the left-right direction, increasing the size of the recesses and protrusions of frills. Consequently, favorable texture is available during wearing, and the visual impression of the user can be further improved by the large frills.

In such an underpants-shaped absorbent article, it is desirable.

According to such an underpants-shaped absorbent article, the inclining elastic members extend to the lower side. This makes it easier to suppress turning-up and displacement of the lower part of the extending portion, enabling the lower part of the extending portion to fit the wearer's buttocks.

that the inclining elastic member does not reach a side end of the absorbent main body in the left-right direction.

According to such an underpants-shaped absorbent article, a region in which no inclining elastic members are disposed is present at the lower end portion of the extending portion. This makes it difficult for the stretching force of the inclining elastic members to be exerted directly on the absorbent main body, making it possible to suppress displacement of the absorbent main body due to being stretched during wearing. Moreover, even when the wearer moves the legs, the line of the inclining elastic members disposed at the buttocks can be suppressed from being twisted and causing the extending portion to be turned up.

According to such an underpants-shaped absorbent article, it is possible to suppress a crease extending in the up-down direction from being more likely to be formed in the inclining elastic members. In addition, appropriate stretchability can be imparted to the outer extending portion. Therefore, due to the inclining elastic members, it becomes easier for the side end portions of the extending portion to fit along the outline of the wearer's buttocks.

According to such an underpants-shaped absorbent article, it is possible to suppress the stiffness of the joint portion from being further increased as a result that the waist elastic member overlaps the joint portion whose stiffness has been increased by means such as welding. Thus, degradation in sense of comfort in the diaper <NUM> can be avoided.

According to such an underpants-shaped absorbent article, it is possible to dispose the elastic members of two different types at an equal pitch, making it possible to simplify adjusting the positions of the elastic members in a manufacturing process. This facilitates manufacturing of the back waist member <NUM>, and allows to suppress increase of manufacturing costs.

According to such an underpants-shaped absorbent article, the pitch of the lateral elastic members in the up-down direction increases, and therefore the stretching force which the lateral elastic members exerts on a unit area of the extending portion decreases. Consequently, a fastening force exerted by the extending portion decreases when the absorbent article is put on, and this prevents the force for fastening at the buttocks from being excessively strong, making it possible to give appropriate fitting to the wearer.

According to such an underpants-shaped absorbent article, the pitch of the lateral elastic members in the up-down direction decreases, and therefore a stretching force by the lateral elastic members easily exerts on the entirety of the extending portion. This makes it easier for the extending portion to fit the wearer's buttocks in surface-to-surface contact. Consequently, it is more likely to suppress separating away from the extending portion during wearing.

According to such an underpants-shaped absorbent article, the gap between the inclining elastic members disposed close to the left-right-direction outermost outer edge portions of the extending portion is narrow, and thus, the stretching force of the inclining elastic members concentrates and is easily exerted on the outer edge portions. Therefore, the side end portions easily fit the outline of the wearer's buttocks, and fit can be further improved.

According to such an underpants-shaped absorbent article, a force with which the outer edge portions of the back waist member is stretched inward in the left-right direction is uneven due to the stretching force of the lateral elastic members. Thus, the shape of the frills formed in the outer edge portions and the size of the recesses and protrusions are irregular. Consequently, design is improved, it is possible to give a wearer with an impression that the frills is made of soft material, and it is possible to realize soften texture during wearing.

In such an underpants-shaped absorbent article,.

According to such an underpants-shaped absorbent article, the lengths by which the lateral elastic members extend outward in the left-right direction beyond the inclining elastic members differs between the left outer edge portion and the right outer edge portion of the extending portion. Thus, the left and right frills are formed to be irregular in terms of shape and size. Consequently, overall design of the extending portion including the frills is improved. In addition, softness of texture is easily perceived by a wearer when the absorbent article is put on.

In such an underpants-shaped absorbent article, it is desirable that
in the underpants-shaped absorbent article in a natural state,
the extending portion includes a portion projecting outside the inclining elastic member in the left-right direction.

According to an underpants-shaped absorbent article, the portion of the extending portion projects outside the inclining elastic members in the left-right direction. Thus, the area of the extending portion appears large, and the buttocks appear wrapped. Consequently, it is possible to provide a user with a sense of security of the wearer's buttocks being reliably covered without exposing externally during wearing.

Hereinafter, as an underpants-shaped absorbent article according to the present invention, an embodiment will be described by presenting a pull-on disposable diaper for an adult as an example. However, the underpants-shaped absorbent article according to the present invention is not limited to a diaper and is usable as a shorts-type sanitary napkin or the like.

<FIG> is a schematic front view of a pull-on disposable diaper <NUM> (hereinafter "diaper") as viewed from the front side. <FIG> is a schematic plan view of the diaper <NUM> in an unfolded and stretched state as viewed from a non-skin side. <FIG> is a schematic cross-sectional view taken along line A-A of <FIG>.

The stretched state of the diaper <NUM> is a state in which the diaper <NUM> is stretched to an extent that causes creases generated in the diaper <NUM> to be substantially visually unrecognizable. Specifically, the stretched state is a state in which the diaper <NUM> is stretched until the dimensions of each member (for example, the later-described skin-side sheets <NUM> and <NUM>, and the like) constituting the diaper <NUM> coincides with the dimension of the member as a single body or becomes a length approximate thereto.

The diaper <NUM> in the underpants-shaped state in <FIG> has an up-down direction, a left-right direction, and a front-back direction that are orthogonal to each other. In the up-down direction, the side closer to the wearer's waist is the upper side, and the side closer to the wearer's crotch is the lower side. In the front-back direction, the stomach side of a wearer is the front side, and the back side of a wearer is the back side. In addition, a direction in which the members constituting the diaper <NUM> are layered as illustrated in <FIG> is the thickness direction. In the thickness direction, a side to be in contact with a wearer is the "skin side", and a side opposite thereto is the "non-skin side".

The diaper <NUM> is a three-piece type diaper constituted by three members: an absorbent main body <NUM>; a front waist member <NUM> that covers the front side of a wearer; and a back waist member <NUM> that covers the back side of a wearer.

In the diaper <NUM> in the unfolded state in <FIG>, the front waist member <NUM> and the back waist member <NUM> are disposed such that the longitudinal direction thereof is in the left-right direction of the diaper <NUM>. The lateral center portion of the front waist member <NUM> is disposed in a longitudinal end portion of the absorbent main body <NUM> on one side, and the lateral center portion of the back waist member <NUM> is disposed in a longitudinal end portion of the absorbent main body <NUM> on the other side.

The diaper <NUM> is two-folded substantially at the longitudinal center of the absorbent main body <NUM>. The front waist member <NUM> and the back waist member <NUM> being joined to each other in two side end portions in the left-right direction by a pair of joint portions <NUM>, becoming in the underpants-shaped state in <FIG> from the unfolded state in <FIG>. In the pull-on diaper <NUM>, a waist opening portion BH and a pair of leg opening portions LH are formed.

The absorbent main body <NUM> includes: an absorbent body <NUM>; a top sheet <NUM> disposed on the skin side in the thickness direction with respect to the absorbent body <NUM>; a back sheet <NUM> disposed on the non-skin side in the thickness direction with respect to the absorbent body <NUM>; and an exterior sheet <NUM>.

The top sheet <NUM> is a liquid-permeable sheet. As the top sheet <NUM>, a hydrophilic spunbond nonwoven fabric, a hydrophilic air-through nonwoven fabric, and the like are exemplified. The back sheet <NUM> is a liquid-impermeable sheet. As the back sheet <NUM>, a polyethylene film and the like are exemplified. As the exterior sheet <NUM>, a hydrophobic SMS nonwoven fabric and the like are exemplified. Although no illustration is provided, a three-dimensional gather portion erectable on the skin side may be disposed in two lateral side portions of the absorbent main body <NUM> by means such as folding the exterior sheet <NUM> toward the skin side and arranging a string-shaped elastic member, for example.

The absorbent body <NUM> includes an absorbent core that absorbs and holds excrement such as urine and the like. As the absorbent core, an absorbent core obtained by shaping liquid-absorbent fibers (e.g., pulp containing super absorbent polymers (SAP)) into a predetermined shape (hourglass shape in this example) is exemplified. The absorbent core may be covered with a liquid-permeable core wrapping sheet, such as tissue paper.

The front waist member <NUM> is a member that has a rectangular shape in the stretched state in <FIG>. The back waist member <NUM> is a member that has, in the stretched state in <FIG>, a shape constituted by a rectangular shape and a substantially reverse trapezoidal shape combined with a lower portion of the rectangular shape. The back waist member <NUM> has a larger planar shape than the front waist member <NUM>.

Specifically, the back waist member <NUM> includes: a rectangular "waist portion <NUM>" (portion surrounded by a, b, c, and d indicated in <FIG>) which overlaps the joint portions <NUM> in the up-down direction; and a substantially reverse trapezoidal "extending portion <NUM>" (portion surrounded by c, d, e, and f indicated in <FIG>) which extends downward in the up-down direction with respect to the lower ends 2a of the joint portions <NUM>. Therefore, the wearer's buttocks can be covered with the extending portion <NUM> even when the diaper <NUM> is of the three-piece type.

In addition, the extending portion <NUM> of the back waist member <NUM> includes a "center extending portion <NUM>" which overlaps the absorbent main body <NUM> in the front-back direction (are overlaid the absorbent main body <NUM> in the thickness direction), and a pair of "outer extending portions <NUM>" extending outward on the two lateral sides of the absorbent main body <NUM>.

In addition, outer edges 32a of the lower portion of the extending portion <NUM> each include: in the center portion in the left-right direction, a "linear portion 32a1" extending in the left-right direction; and in the two end portions in the left-right direction, "inclining portions 32a2" extending downward and inclining inward in the left-right direction. The linear portion 32a1 extends outward on the two lateral sides of the absorbent main body <NUM>.

As illustrated in <FIG>, the front waist member <NUM> includes the skin-side sheet <NUM>, a non-skin-side sheet <NUM>, a cover sheet <NUM>, and a plurality of waist elastic members <NUM> extending in the left-right direction. The plurality of waist elastic members <NUM> are disposed in the front waist member <NUM> and arranged side-by-side at intervals in the up-down direction.

The back waist member <NUM> includes a skin-side sheet <NUM>, a non-skin-side sheet <NUM>, and a cover sheet <NUM>. In the waist portion <NUM> of the back waist member <NUM>, a plurality of waist elastic members <NUM> are each disposed extending in the left-right direction. In the extending portion <NUM>, a plurality of inclining elastic members <NUM> are each disposed inclined in the left-right direction, and a plurality of lateral elastic members <NUM> are each disposed extending in the left-right direction.

Specifically, the plurality of waist elastic members <NUM> are disposed in the waist portion <NUM> and arranged side-by-side at intervals in the up-down direction. The plurality (three in <FIG>) of the inclining elastic members <NUM> are disposed in left-right-direction side end portions of the extending portion <NUM> along the inclining portions 32a2 of the outer edge 32a of the extending portion <NUM>, and are arranged side-by-side at intervals in the left-right direction. In other words, the inclining elastic members <NUM> are disposed extending downward and inclining inward in the left-right direction. The plurality (five in <FIG>) of lateral elastic members <NUM> are disposed in the extending portion <NUM> and arranged side-by-side at intervals in the up-down direction.

The skin-side sheets <NUM> and <NUM> and the non-skin-side sheets <NUM> and <NUM> are disposed on the non-skin side in the thickness direction with respect to the absorbent main body <NUM>. The cover sheets <NUM> and <NUM> each have a shorter vertical length than the skin-side sheets <NUM> and <NUM> and the non-skin-side sheets <NUM> and <NUM>. The cover sheets <NUM> and <NUM> are disposed on the skin side in the thickness direction with respect to the absorbent main body <NUM>, and cover the longitudinal end portions of the absorbent main body <NUM>. As these sheets <NUM> to <NUM> and <NUM> to <NUM>, soft sheets of SMS nonwoven fabric or the like are exemplified.

The waist elastic members <NUM> and <NUM> and the lateral elastic members <NUM> are fixed with an adhesive (for example, a hot-melt adhesive or the like) between the skin-side sheet <NUM> (<NUM>) and the non-skin-side sheet <NUM> (<NUM>) so as to be stretchable in the left-right direction, while being stretched in the left-right direction. The inclining elastic members <NUM> are also fixed with an adhesive between the skin-side sheet <NUM> (<NUM>) and the non-skin-side sheet <NUM> (<NUM>) so as to be stretchable in a direction inclining with respect to the left-right direction, while being stretched in the inclining direction.

In the figures, illustrated are only stretchable portions (effective length portions fixed in a stretched state to the sheets) of each of the elastic members <NUM> and <NUM> to <NUM>. In portions that are not illustrated, non-stretchable portions of each of the elastic members <NUM> and <NUM> to <NUM> may be present.

In <FIG>, in the waist elastic members <NUM> and the lateral elastic members <NUM> on the back side overlapping the absorbent body <NUM> in the up-down direction, no stretchable portions of the elastic members <NUM> and <NUM> are present in the center portion in the left-right direction. Due to such absence of the stretchable portions of the elastic members <NUM> and <NUM> in the portions which overlaps the absorbent main body <NUM> in the front-back direction (are overlaid the absorbent main body <NUM> in the thickness direction), it is possible to suppress contraction of the absorbent main body <NUM> in the left-right direction.

As each of the elastic members <NUM> and <NUM> to <NUM>, a string-shaped elastic member of rubber, spandex, or the like is exemplified. The elastic members <NUM> and <NUM> to <NUM> are, however, not limited thereto and may be sheet-shaped elastic members of expandable nonwoven fabric, expandable film, or the like.

The diaper <NUM> includes the extending portion <NUM> in a region located on the lower side (crotch side) of the back waist member <NUM> in the up-down direction. During wearing of the diaper <NUM>, the extending portion <NUM> covers the wearer's buttocks. In a state in which the diaper <NUM> is stretched in the left-right direction, the left-right-direction width of each of the outer extending portions <NUM>, which are regions of the extending portion <NUM> not overlapping the absorbent main body <NUM>, is larger than the left-right-direction width of the center extending portion <NUM>, which is a region overlapping the absorbent main body <NUM>. In other words, in a state in which the diaper <NUM> is stretched in the left-right direction as illustrated in <FIG>, the distance W322l in the left-right direction between a left side end 10el of the absorbent main body <NUM> and a left side end 30el of the back waist member <NUM> is larger than the distance W10 between the left side end 10el and a right side end 10er of the absorbent main body <NUM> (W322l > W10). Similarly, the distance W322r in the left-right direction between the right side end 10er of the absorbent main body <NUM> and the right side end 30er of the back waist member <NUM> is larger than the distance W10 between the left side end 10el and the right side end 10er of the absorbent main body <NUM> (W322r > W10). Therefore, it is possible to reliably cover even the wide buttocks of an adult, which is a target wearer of the diaper <NUM>.

In the outer edge 32a of the outer extending portions <NUM>, the inclining elastic members <NUM> are disposed in a region extending along the inclining portions 32a2. Due to stretchability imparted by the inclining elastic members <NUM>, the outer edge 32a easily fits along the outline of the wearer's buttocks. In other words, in the diaper <NUM> of the present embodiment, the inclining elastic members <NUM> are located on the outer side of the apex of the wearer's buttocks during wearing. It is thus possible to wrap around the wearer's buttocks while the outer extending portions <NUM> are not turned up even when the area of the outer extending portions <NUM> is large (even when the distances W322l and W322r in the left-right direction are large).

Moreover, when viewed in the front-back direction (thickness direction), the inclining elastic members <NUM> and the lateral elastic members <NUM> overlap each other (see <FIG>) in the left-right-direction side end portions of the outer extending portions <NUM>, and accordingly the stiffness of the outer extending portions <NUM> increases in these two side end portions where the two elastic members <NUM> and <NUM> overlap each other. This makes it easier to maintain a state in which the outer edge 32a of the outer extending portions <NUM> fits along the outline of the wearer's buttocks. Accordingly, even when the wearer moves the body, this makes it less likely for the outer extending portions <NUM> to turn up or displace.

In the diaper <NUM>, due to the extending portion <NUM> having such a configuration, it is possible to achieve favorable fit while widely covering the wearer's buttocks.

At the extending portion <NUM> of the diaper <NUM>, the lateral elastic members <NUM> extend outward in the left-right direction with respect to the inclining elastic members <NUM>. <FIG> is an illustration of an arrangement of the inclining elastic members <NUM> and the lateral elastic members <NUM> in the outer extending portions <NUM> of the diaper <NUM>. <FIG> illustrates an enlarged view of a portion in the vicinity of the outer edge 32a of the outer extending portion <NUM> on the right side in the left-right direction. As illustrated in <FIG>, the lateral elastic members <NUM> include portions extending outward in the left-right direction with respect to the inclining elastic members <NUM>.

In regions on the outer sides of the inclining elastic members <NUM> in the left-right direction, the skin-side sheet <NUM> and the non-skin-side sheet <NUM> of the back waist member <NUM> are joined to each other in the thickness direction with a hot-melt adhesive or the like. And, between the sheet <NUM> and <NUM>, the extending portions of the lateral elastic members <NUM> are disposed. Therefore, in the outer extending portions <NUM>, at the regions outside the inclining elastic members <NUM> in the left-right direction, the portions where the lateral elastic members <NUM> are disposed are pulled inward in the left-right direction due to an action of the stretching force of the lateral elastic members <NUM>. Consequently, in the regions (that is, outer edge portions) of the outer extending portions <NUM> (extending portion <NUM>) outside the inclining elastic members <NUM> in the left-right direction, the portions where the lateral elastic members <NUM> are disposed easily contract inward in the left-right direction. On the other hand, regions where the lateral elastic members <NUM> are not disposed do not easily contract inward in the left-right direction. Consequently, the outer edge 32a of the outer extending portions <NUM> deforms into a frill shape having recesses and protrusions in the left-right direction, as illustrated in <FIG>. As a result of the outer edge 32a having the frill shape, the texture of the outer edge 32a during wearing of the diaper <NUM> is improved, making it less likely for a wearer to feel discomfort. In addition, the frill shape formed along the leg opening portions LH can provide the user a visually soft impression.

In the diaper <NUM> of the present embodiment, the lateral elastic members <NUM> extending outward in the left-right direction with respect to the inclining elastic members <NUM> reach the outer ends (the outer edge 32a of the outer extending portions <NUM>) of the extending portion <NUM> in the left-right direction. Consequently, in regions outside the inclining elastic members <NUM> in the left-right direction, a larger stretching force of the lateral elastic members <NUM> is exerted. In addition, the stretching force makes it easier for the outer edge 32a of the outer extending portions <NUM> to be stretched inward in the left-right direction, increasing the size of the recesses and protrusions of the frills. Therefore, the favorable texture is realized during wearing, and large frills can improve the visual impression of a user.

As a result of exerting the stretching force by the lateral elastic members <NUM> on the entirety of the outer extending portions <NUM> in the left-right direction, the inclining elastic members <NUM> and the entirety of the frills in a natural state of the diaper <NUM> are in a state of being folded inward in the left-right direction and toward the skin side in the thickness direction, as illustrated in <FIG>. A part of the regions of the outer extending portions <NUM> (extending portion <NUM>) projects outside the inclining elastic members <NUM> in the left-right direction. In other words, in the natural state of the diaper <NUM>, the extending portion <NUM> includes projecting portions 32oh projecting outside the inclining elastic members <NUM> in the left-right direction. In the external appearance of the diaper <NUM>, the projecting portions 32oh form outer side ends of the extending portion <NUM> in the left-right direction (see <FIG>). Due to the projecting portions 32oh projecting outside the inclining elastic members <NUM> in the left-right direction, the area of the extending portion <NUM> (outer extending portions <NUM>) appears large, and the buttocks appear wrapped. Consequently, it is possible to provide a user with a sense of security of the wearer's buttocks being reliably covered without exposing externally during wearing of the diaper <NUM>.

Here, the "natural state" of the diaper <NUM> is a state of the diaper <NUM> after being left for a predetermined period of time. For example, by stretching the front waist member <NUM> and the back waist member <NUM> of the diaper <NUM> outward toward two left-right-direction-side, the waist members <NUM> and <NUM> are made in an "stretched state'. Thereafter keeping the stretched state for approximately <NUM> seconds, and then the stretching of the diaper <NUM> is released, and the diaper <NUM> is placed on a flat surface of a desk or the like. A state after a lapse of five minutes with the diaper <NUM> thus placed flat on the flat surface is defined as the natural state.

As illustrated in <FIG>, in the outer extending portions <NUM> (extending portion <NUM>), a plurality of the lateral elastic members <NUM> are disposed at intervals in the up-down direction. Among these lateral elastic members <NUM>, the position of the lowermost lateral elastic member <NUM> is higher than the position of the lower end of the inclining elastic members <NUM>. In other words, in the up-down direction, the inclining elastic members <NUM> extend downward beyond the lowermost lateral elastic member <NUM>. The inclining elastic members <NUM> extending downward beyond the lateral elastic members <NUM> makes it easier for the stretching force of the inclining elastic members <NUM> to be exerted on a further lower part of the outer extending portions <NUM>. This makes it easier to suppress turning-up and displacement of the lower part of the outer extending portions <NUM> when the diaper <NUM> is put on. In addition, as a result of the inclining elastic members <NUM> being disposed extending downward along the outline of the wearer's buttocks, it is possible to further improve the fit around the wearer's buttocks.

In the diaper <NUM>, the inclining elastic members <NUM> are disposed inclining downward in the up-down direction from the outer sides toward the inner side in the left-right direction. The inclining elastic members <NUM> do not reach two side ends 10el and 10er of the absorbent main body <NUM> in the left-right direction. In other words, a predetermined interval is provided between left-right-direction inner ends 37ei of the inclining elastic members <NUM> and the left-right-direction outer side end 10el (10er) of the absorbent main body <NUM> (see <FIG>). The inclining elastic members <NUM> thus not overlaid the absorbent main body <NUM> in the thickness direction makes it difficult for the stretching force of the inclining elastic members <NUM> to be exerted on the absorbent main body <NUM>. If the absorbent main body <NUM> and the inclining elastic members <NUM> overlap each other, there is a risk that, when the diaper <NUM> is put on, the absorbent main body <NUM> is easily displaced from the wearer's crotch as a result of the absorbent main body <NUM> being stretched obliquely along the inclination of the inclining elastic members <NUM>. Moreover, as a result of the extending portion <NUM> being also pulled up along the absorbent main body <NUM>, there is a case where the buttocks are less likely to be covered by the extending portion <NUM>. In contrast, in the diaper <NUM> of the present embodiment, the stretching force of the inclining elastic members <NUM> is less likely to be exerted on the absorbent main body <NUM>, which making it possible to suppress displacement of the absorbent main body <NUM> during wearing of the diaper <NUM>. In addition, it becomes easier for the wearer's buttocks to be covered the extending portion <NUM>. Consequently, even when the wearer moves the legs, the line of the inclining elastic members <NUM> disposed at the buttocks can be suppressed from being twisted and causing the extending portion <NUM> to be turned up.

Incidentally, the diaper <NUM> is packaged after being manufactured in a factory or the like and is distributed to the market in a predetermined packaged state. Specifically, when the diaper <NUM> is to be packaged, the front waist member <NUM> and the back waist member <NUM> of the diaper <NUM> in the natural state (underpants-shaped state) are folded at folding positions FL extending in the up-down direction (longitudinal direction in <FIG>), from the outer side toward the inner side in the left-right direction. Then the front waist member <NUM> and the back waist member <NUM> are folded up at folding positions FL2 (see <FIG>) extending in the left-right direction such that the respective heights thereof become substantially half in the up-down direction. The inclining elastic members <NUM> are disposed such that the inclining elastic members <NUM> and the folding positions FL (and FL2) do not overlap each other when the diaper <NUM> in a state of being thus folded up is viewed in the front-back direction. Consequently, the diaper <NUM> is able to be distributed to the market with the inclining elastic members <NUM> not folded up at the folding positions FL. If the inclining elastic members <NUM> overlap the folding positions FL, the inclining elastic members <NUM> will be distributed to the market in a state of being folded at the folding positions FL. In this case, a crease is more likely to be formed in the inclining elastic members <NUM>, and there is a risk that the inclining elastic members <NUM> thus having creases become unable to impart appropriate stretchability to the outer extending portions <NUM> (extending portion <NUM>). In contrast, in the diaper <NUM> of the present embodiment, the inclining elastic members <NUM> are arranged separated from the folding positions FL, making it possible to suppress a crease from being more likely to be formed, and are able to impart appropriate stretchability to the outer extending portions <NUM> (extending portion <NUM>). Accordingly, due to the inclining elastic members <NUM>, it becomes easier for the side end portions of the outer extending portions <NUM> to fit along the outline of the wearer's buttocks.

Next, <FIG> is an illustration of an arrangement of the waist elastic members <NUM> and the lateral elastic members <NUM> in the back waist member <NUM>. <FIG> illustrates a right region of the back waist member <NUM> (waist portion <NUM> and extending portion <NUM>) in a state of being stretched in the left-right direction and the up-down direction. As illustrated in <FIG>, a plurality of the waist elastic members <NUM> are disposed in the waist portion <NUM> of the back waist member <NUM> at intervals in the up-down direction. These waist elastic members <NUM> are disposed inside the joint portions <NUM> in the left-right direction. In other words, outer side ends 36e0 of the waist elastic members <NUM> in the left-right direction are positioned inside the joint portions <NUM> in the left-right direction, and the waist elastic members <NUM> and the joint portions <NUM> do not overlap each other. Stiffness of the joint portions <NUM> is increased by joining means, such as welding. Thus, if the waist elastic members <NUM> overlap the joint portions <NUM>, stiffness of the joint portions <NUM> is further increased, which easily imparts discomfort to a wearer during wearing of the diaper <NUM>. In contrast, in the present embodiment, the waist elastic members <NUM> are disposed not to overlap the joint portions <NUM>, making it possible to suppress stiffness of the joint portions <NUM> from being increased. It is thus possible to avoid degradation in sense of comfort in the diaper <NUM>.

In <FIG>, d36 denotes an interval in the up-down direction between two of the waist elastic members <NUM> adjacent to each other in the up-down direction, and d38 denotes an interval in the up-down direction between two of the lateral elastic members <NUM> adjacent to each other in the up-down direction. The interval d36 and the interval d38 are equal to each other (d36 = d38). In other words, in the diaper <NUM>, the waist elastic members <NUM> and the lateral elastic members <NUM> are disposed at an equal pitch in the up-down direction. Enabling to dispose the elastic members of two types at an equal pitch makes it possible to simplify adjusting the positions of the elastic members <NUM> and <NUM> in a manufacturing process of the diaper <NUM> (back waist member <NUM>). This facilitates manufacturing of the back waist member <NUM>, and allows to suppress increase of manufacturing costs.

In the back waist member <NUM>, the interval d38 of the lateral elastic members <NUM> in the up-down direction may be larger than the interval d36 of the waist elastic members <NUM> in the up-down direction (d38 > d36). In this case, the pitch of the lateral elastic members <NUM> in the up-down direction increases in the extending portion <NUM> (outer extending portions <NUM>) of the back waist member <NUM>, and therefore, the stretching force which the lateral elastic members <NUM> exerts on a unit area of the extending portion <NUM> decreases. Accordingly, during wearing of the diaper <NUM>, the fastening force by the outer extending portions <NUM> that cover the wearer's buttocks decreases. This prevents the force for fastening at the buttocks from being excessively strong, and it is possible to suppress degradation in sense of comfort of the diaper <NUM> and to give appropriate fitting to the wearer.

Conversely, in the back waist member <NUM>, the interval d38 of the lateral elastic members <NUM> in the up-down direction may be smaller than the interval d36 of the waist elastic members <NUM> in the up-down direction (d38 < d36). While it is possible to decrease the fastening force when increasing the pitch of the lateral elastic members <NUM> in the up-down direction as described above, there is a case in which the outer extending portions <NUM> separates away from the wearer's buttocks or turning-up thereof occurs, for example, when the wearer's body (buttocks) is small. In this case, decreasing the pitch of the lateral elastic members <NUM> in the up-down direction makes it easier for the stretching force by the lateral elastic members <NUM> to be exerted on the entirety of the outer extending portions <NUM>, and this makes it easier for the outer extending portions <NUM> to fit along the wearer's buttocks in surface-to-surface contact. Consequently, it is more likely to suppress separating away from the outer extending portions <NUM> during wearing of the diaper <NUM>.

Thus, optimal fit can be achieved in the diaper <NUM> by adjusting the up-down-direction pitches of the waist elastic members <NUM> and the lateral elastic members <NUM> in accordance with the target wearer's body (buttocks) size, a usage and the like. For example, in a usage such that a wearer of the diaper <NUM> lies in a bed for a prolonged period, if the diaper <NUM> in which the pitch of the lateral elastic members <NUM> is wide is selected, excessive fastening at the buttocks is suppressed and it is possible to prevent the wearer from feeling discomfort. In contrast, in a usage such that a wearer lives an ordinary life in a state of wearing the diaper <NUM>, if the diaper <NUM> in which the pitch of the lateral elastic members <NUM> is narrow is selected, displacement and turning-up of the outer extending portions <NUM> is suppressed even when the wearer moves the body, and it is possible for the wearer to feel favorable fit.

In the diaper <NUM>, the plurality of inclining elastic members <NUM> are disposed with gaps therebetween in the left-right direction, but each gap between each pair of the inclining elastic members <NUM> adjacent to each other in the left-right direction is not constant. In <FIG>, three inclining elastic members 37a, 37b, and 37c are disposed from the outer side toward the inner side in the left-right direction. The gap W37ab in the left-right direction between the inclining elastic members 37a and 37b is not constant, and the gap W37bc in the left-right direction between the inclining elastic members 37b and 37c is also not constant. In other words, the inclining elastic members 37a to 37c are disposed along the inclining portions 32a2 (outer edge 32a) of the outer extending portions <NUM>, but are not disposed exactly parallel to the inclining portions 32a2. That is, the inclining elastic members 37a to 37c are disposed to meander with respect to the inclining direction of the inclining portions 32a2.

In the diaper <NUM>, the maximum value of the gap W37ab in <FIG> is smaller than the minimum value of the gap w37bc. In other words, of the left-right-direction gaps between the inclining elastic members <NUM> adjacent to each other in the left-right direction, the maximum value of the outermost gap is smaller than the minimum value of the other gaps. Due to the gap between the inclining elastic members 37a and 37b arranged nearest to outer side ends (outer edge portions) of the inclining portions 32a2 in the left-right direction thus being narrow, the stretching force of the inclining elastic members <NUM> (37a and 37b) concentrates and is easily exerted on the side end portion. In other words, a contraction force exerted on a unit area of the outer edge portions of the extending portion <NUM> increases. Thus, the outer edge portions easily fit the outline of the wearer's buttocks during wearing of the diaper <NUM>, and fit can be further improved.

In the diaper <NUM>, due to the inclining elastic members 37a disposed outermost in the left-right direction being disposed to meander with respect to the inclining direction of the inclining portions 32a2, the distance in the left-right direction between the inclining elastic members 37a and the inclining portions 32a2 (outer edge 32a of the outer extending portions <NUM>) is also not constant. Thus, the length W38e of the lateral elastic members <NUM> extending outward in the left-right direction beyond the inclining elastic members <NUM> is also not constant. In other words, the length by which each of the plurality of lateral elastic members <NUM> extends outward in the left-right direction beyond the inclining elastic members <NUM> differs. Therefore, due to the stretching force of the lateral elastic members <NUM>, the force with which the outer edge portions of the inclining portions 32a2 are stretched inward in the left-right direction is uneven. The shape of frills formed in the outer edge portions and the size of the recesses and protrusions are thus irregular. Consequently, design of the outer extending portions <NUM> is improved. Moreover, it is possible to give a wearer with an impression that the frills is made of soft material, and it is possible to realize soften texture during wearing.

The diaper <NUM> can be modified as in a first modified example and a second modified example described below. <FIG> is a schematic plan view of the diaper <NUM> of the first modified example in an unfolded and stretched state as viewed from the skin side. <FIG> is a schematic plan view of the diaper <NUM> of the second modified example in an unfolded and stretched state as viewed from the skin side.

In the diaper <NUM> of the first modified example, the shape of the back waist member <NUM> differs from that in the aforementioned embodiment. Specifically, as illustrated in <FIG>, at the outer edge 32a of the back waist member <NUM>, the linear portion 32a1 and the inclining portions 32a2 are continuously connected to each other by curved portions 32a3. In other words, on the lower side of the back waist member <NUM> (outer extending portions <NUM>), part of the outer edge 32a is formed in a curved manner. The other configurations are identical to those of the aforementioned diaper <NUM>, and thus, detailed description thereof is omitted.

In the modified example <NUM>, no corner is formed at the outer edge 32a of the outer extending portions <NUM>. Thus, the outer edge 32a of the outer extending portions <NUM> is in smooth contact with the wearer's buttocks when the diaper <NUM> is put on and can impart a soft texture to the wearer. In addition, the inclining elastic members <NUM> are disposed in a curved manner along the curved portions 32a3, and a part of the inclining elastic members <NUM> extend parallel to the left-right direction along the linear portion 32a1. In other words, the stretchability in the left-right direction is exerted in the lower end portion (linear portion 32a1) of the outer edge 32a of the outer extending portions <NUM>. Consequently, during wearing of the diaper <NUM>, the outer extending portions <NUM> easily follow the outline of the wearer's buttocks, and fitting around the buttocks can be further improved.

In the diaper <NUM> of the second modified example, the arrangement of the inclining elastic members <NUM> is left-right asymmetric. Specifically, the inclining elastic members <NUM> disposed on the left-right-direction one side of the back waist member <NUM> are positioned further inside (that is, closer to the absorbent main body <NUM>) in the left-right direction than the inclining elastic members <NUM> disposed on the left-right-direction other side are positioned. The other configurations are identical to those of the aforementioned diaper <NUM>.

In the example in <FIG>, when the length by which the lateral elastic members <NUM> extend on the right side (outer side in the left-right direction) beyond the inclining elastic members <NUM> in the outer extending portion <NUM> on the right side of the absorbent main body <NUM> is defined as a length W38er, and the length by which the lateral elastic members <NUM> extend leftward (outward in the left-right direction) beyond the inclining elastic members <NUM> in the outer extending portion <NUM> located on the left side of the absorbent main body <NUM> is defined as a length W38el, the length W38er and the length W38el differ from each other. In other words, the length by which the lateral elastic members <NUM> extend outward in the left-right direction beyond the inclining elastic members <NUM> differs between the left outer edge portion and the right outer edge portion of the outer extending portions <NUM>. Consequently, left and right frills are formed to have irregular shapes and sizes. Therefore, overall design of the outer extending portions <NUM> is improved. In addition, it is possible to cause a wearer to perceive soft texture during wearing.

Although the embodiment of the present disclosure have been described hereinabove, the above embodiment of the present disclosure is simply to facilitate understanding of the present disclosure and are not in any way to be construed as limiting the present disclosure. The present disclosure may variously be changed or altered and encompass equivalents thereof.

In the aforementioned embodiment, nonwoven fabric is presented as an example of the material of each of the exterior sheet <NUM>, the front waist member <NUM>, and the back waist member <NUM>; however, the material thereof is in no way limited to nonwoven fabric. For example, woven fabric or a sheet material other than woven fabric may be employed. Incidentally, the exterior sheet <NUM> may be omitted. In this case, the back sheet <NUM> forms the exterior of the absorbent main body <NUM>.

Claim 1:
An underpants-shaped absorbent article having an up-down direction, a left-right direction, and a front-back direction that are orthogonal to each other,
the underpants-shaped absorbent article comprising:
an absorbent main body (<NUM>);
a front waist member (<NUM>); and
a back waist member (<NUM>),
the front waist member (<NUM>) and the back waist member (<NUM>) being joined to each other in two side end portions in the left-right direction by a pair of joint portions (<NUM>),
the back waist member (<NUM>) including an extending portion (<NUM>) that extends downward with respect to the joint portions (<NUM>),
the extending portion (<NUM>) including
an inclining elastic member (<NUM>) being inclined with respect to the left-right direction, in a left-right-direction one side end portion of the extending portion (<NUM>),
an inclining elastic member (<NUM>) being inclined with respect to the left-right direction, in a left-right-direction other side end portion of the extending portion (<NUM>),
and a lateral elastic member (<NUM>) extending in the left-right direction,
when viewed in the front-back direction, the inclining elastic members (<NUM>) and the lateral elastic member (<NUM>) having an overlapping portion where the inclining elastic member (<NUM>) and the lateral elastic member (<NUM>) overlap each other, wherein
in a state in which the underpants-shaped absorbent article is stretched in the left-right direction, a length from a side end of the absorbent main body (<NUM>) on one side in the left-right direction to a side end of the back waist member (<NUM>) on the one side in the left-right direction is longer than a length of the absorbent main body (<NUM>) in the left-right direction, and wherein
the arrangement of the inclining elastic members is left-right asymmetric, the inclining elastic member disposed on the left-right direction one side being closer to the absorbent main body than the inclining elastic member disposed on the left-right direction other side, such that
concerning a length by which the lateral elastic member (<NUM>) extends on a left side beyond the inclining elastic member (<NUM>) in the extending portion located on the left side of the absorbent main body (<NUM>), and
concerning a length by which the lateral elastic member (<NUM>) extends on a right side beyond the inclining elastic member (<NUM>) in the extending portion located on the right side of the absorbent main body (<NUM>),
these lengths differ from each other.