TWM497013U - Absorbent article - Google Patents

Description

Absorbent article

This creation is about an absorbent article such as disposable diapers.

Heretofore, an absorbent article including a front sheet having a concavo-convex structure for preventing leakage of bodily fluids such as soft stools and menstrual blood has been known.

For example, Patent Document 1 discloses a disposable diaper including a front sheet provided with a projection having a plurality of first projections having a large cross-sectional area at the center and on both sides. A plurality of second projections having a small cross-sectional area. In the disposable diaper described in Patent Document 1, since the front sheet has a plurality of protruding portions, the cushioning property at the time of wearing is good, and for example, the wet back after absorption of the soft stool is small, and the feeling of use is good. Further, in the disposable diaper described in Patent Document 1, the width of the plurality of second projections provided on both sides in the crotch region is smaller than the width of the plurality of first projections provided at the center, and therefore For example, it is possible to suppress the spread of the soft stool in the width direction of the diaper.

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2004-049918

However, in the disposable diaper described in Patent Document 1, the projections are arranged so as to extend over the entire length in the longitudinal direction and are formed in parallel with each other. Therefore, it is difficult to discharge the soft urethane in the back side region, for example, in the back side region. It spreads in the width direction, so that a large amount of softness easily spreads to the underarm area. If such a large amount of softness spreads to the underarm area and exceeds the absorption capacity of the underarm area, the side leakage of the soft stool cannot be prevented.

Therefore, the present invention relates to providing an absorbent article that solves the above problems.

The present invention relates to an absorbent article comprising a vertically long absorbent body comprising a liquid-permeable front sheet disposed on the opposite side of the skin and a liquid disposed on the non-skin facing side. A transparent back sheet and an absorber disposed between the two sheets. The absorbent body is divided into a ventral region on the ventral side of the wearer when worn, a backside region on the back side, and a crotch region disposed between the ventral region and the dorsal region. The front sheet includes at least a fluffy non-woven fabric having a concavo-convex structure, and the concavo-convex structure includes a plurality of convex portions that are raised on the skin facing surface side and a concave portion that is adjacent to the concave portion. The front sheet other than the back side region is provided with at least a pair of narrow convex portion regions on both side portions of the absorbent body in the longitudinal direction, and the narrow convex portion region includes a width smaller than the underarm region. a plurality of convex portions of the width of the convex portion having the largest width among the central portions.

1A‧‧‧ diapers

2‧‧‧Front sheet

3‧‧‧Back sheet

4‧‧‧Acceptor

5‧‧‧Absorbing ontology

5m‧‧‧Central Department

5s‧‧‧ side

6‧‧‧Three-dimensional folds

7‧‧‧Buckle belt

8‧‧‧Fixed tape

9‧‧‧Narrow convex area

9a‧‧‧1st narrow convex area

9b‧‧‧Central narrow convex area

9c‧‧‧2nd central narrow convex area

21‧‧‧ convex

21a‧‧‧ convex

21b‧‧‧ convex

22‧‧‧ recess

22a‧‧‧ recess

22b‧‧‧ recess

41‧‧‧Absorbable core

41s‧‧‧ Space Department

41s1‧‧‧1st Space Department

41s2‧‧‧Second Space Department

41s3‧‧‧3rd Space Department

42‧‧‧Package

61‧‧‧Flexible components

62‧‧‧Three-dimensional pleat forming sheet

63‧‧‧ Leg elastic members

90‧‧‧ side

100‧‧‧pressure roller

101‧‧‧ convex area

102‧‧‧1st roll

103‧‧‧2nd roller

104‧‧‧Continuous body of disposable diapers

105‧‧‧Continuous body of disposable diapers

A‧‧‧ Ventral area

B‧‧‧Back side area

C‧‧‧胯下区域

CL‧‧‧ center line

T‧‧‧ area

W‧‧‧Maximum width

W1‧‧‧Width

W2‧‧‧Width

W3‧‧‧Width

W4‧‧‧Width

W5‧‧‧Width

W6‧‧‧Width

W7‧‧‧Width

W8‧‧‧Width

X‧‧‧ direction

Y‧‧‧ direction

Fig. 1 is a partially broken plan view showing the unfolded diaper of the unfolded type according to the first embodiment of the present invention as seen from the side of the front sheet.

Figure 2 is a cross-sectional view taken along line I-I of Figure 1.

Fig. 3 is a plan view showing an absorbent core constituting an absorbent body of the disposable diaper shown in Fig. 1.

Figure 4 is a top plan view of the topsheet of the disposable diaper of Figure 1.

Fig. 5 is a schematic view showing an example of a press roll for producing a disposable diaper of the unfolded type according to the first embodiment of the present invention.

Fig. 6 is a partially broken plan view showing the unfolded diaper of the unfolded type according to the second embodiment of the present invention as seen from the side of the front sheet.

Fig. 7 is a sectional view taken along line II-II of Fig. 6 (corresponding to the diagram of Fig. 2).

Figure 8 is a top plan view of the topsheet of the disposable diaper shown in Figure 6 (corresponding to Figure 4).

Fig. 9 is a plan view (corresponding to Fig. 3) of an absorbent core for use as a disposable diaper according to another embodiment of the present invention.

Fig. 10 is a plan view (corresponding to Fig. 3) of an absorbent core for use as a disposable diaper according to still another embodiment of the present invention.

Fig. 11 is a plan view (corresponding to Fig. 3) of an absorbent core for use in a disposable diaper according to still another embodiment of the present invention.

Fig. 12 is a plan view (corresponding to Fig. 3) of an absorbent core for use as a disposable diaper according to still another embodiment of the present invention.

Fig. 13 is a plan view (corresponding to Fig. 4) of a top sheet of a disposable diaper including the absorbent core shown in Fig. 9 as another embodiment of the present invention.

Fig. 14 is a plan view (corresponding to Fig. 4) of a top sheet of a disposable diaper including the absorbent core shown in Fig. 10 as another embodiment of the present invention.

Figure 15 is a plan view of another topsheet for use as a disposable diaper comprising the absorbent core of Figure 10 as another embodiment of the present invention (corresponding to Figure 4)

Fig. 16 is a plan view (corresponding to Fig. 4) of a top sheet for use in a disposable diaper comprising the absorbent core shown in Fig. 11 as another embodiment of the present invention.

Fig. 17 is a plan view (corresponding to Fig. 4) of a top sheet for a disposable diaper including the absorbent core shown in Fig. 12 as another embodiment of the present invention.

Hereinafter, the absorbent article of the present invention will be described based on a preferred embodiment with reference to Figs. 1 to 4 . Fig. 1 is a partially broken plan view showing the disposable diaper of the first embodiment of the present invention as viewed from the front sheet side, and Fig. 2 is a cross-sectional view taken along line I-I of Fig. 1. Further, Fig. 3 is a plan view showing the absorbent core of the absorbent body of the disposable diaper shown in Fig. 1, and Fig. 4 shows the front sheet of the disposable diaper shown in Fig. 1. Top view.

As shown in Fig. 1, the disposable diaper 1A of the first embodiment (hereinafter also referred to as "diaper" 1A") has a vertically long absorbent body 5 comprising a liquid-permeable front sheet 2 disposed on the opposite surface side of the skin, and a back surface disposed on the non-skin facing side. The sheet 3 and the absorber 4 disposed between the two sheets 2 and 3. The absorptive body 5 is divided into a ventral region A located on the ventral side of the wearer when worn, a back side region B on the back side, and a crotch region C disposed between the ventral region A and the back side region B. As shown in Fig. 1, the diaper 1A is formed bilaterally symmetrically with respect to a center line CL extending in the longitudinal direction.

In the present invention, the diaper of the following 1) to 3) is divided into the diaper in the state in which the diaper is unfolded, and the ventral region A, the back side region B, and the underarm region C are determined. Specifically, in the diaper according to the present embodiment, in a state in which the diaper is unfolded (FIG. 1), 1) a region corresponding to the retracted position of the outer covering body is referred to as a crotch region C, and will be located in the lower crotch region C. The area on the ventral side of the wearer is set as the ventral area A, and the area on the back side of the wearer's lower area C is set as the back side area B. The retracted position refers to a region in which the outer wrap is retracted from the both sides in the Y direction described below toward the center in the width direction (the following X direction), and the width of the outer wrap is narrowed, and this region is referred to as the crotch region C. The outer cover as used herein means a sheet disposed on the outermost side of the non-skin side of the diaper, and generally refers to a non-woven fabric disposed on the outer side of the liquid-impermeable film sheet, but does not include the non-woven fabric. When only a film having a liquid impermeability is included, the film is regarded as an outer envelope. The film sheet is a few millimeters larger than the non-woven fabric of the same size or as an outer covering. Further, in the front side portion A and the back side portion B, the outer covering body protrudes more than the crotch portion C in the width direction and has a wider width. Further, 2) in the case where the side portion of the outer covering body is formed linearly in the longitudinal direction (Y direction) and the diaper for fixing the flap is provided on both sides of the back side, the region including the flap is set as the back side region. B. The portion on the ventral side corresponding to the length of the flap, that is, the portion where the flap is worn when worn, is the ventral region A, and the region between the back region B and the ventral region A is set as the underarm region C. . In the case where the diaper of the region cannot be determined according to the above descriptions 1) and 2), the ventral side of the wearer when the diaper 3 is equally divided in the longitudinal direction in the state in which the diaper is unfolded is set. Ventral area A, will back The side is defined as the back side region B, and the underarm region between the ventral side and the back side is set as the underarm region C.

When the diaper 1A is described in detail, the absorbent main body 5 of the diaper 1A is in the longitudinal direction (hereinafter also referred to as "Y direction" in the state of being stretched as shown in Fig. 1. The Y direction: refers to the center line CL. The direction) has a ventral region A, a crotch region C, and a dorsal region B. In the state in which the diaper 1A is stretched, the region corresponding to the retracted position of the outer wrapper is set to the crotch region C, and the lower portion A, the crotch portion C, and the back side portion B are located closer to the crotch region. The area on the ventral side of the wearer is set as the ventral area A, and the area on the back side of the wearer in the lower squat area is referred to as the back side area B (the purpose is to match the diaper of the classification of (1) above. ). In addition, the direction orthogonal to the longitudinal direction (Y direction) is used as the width direction of the diaper 1A (hereinafter also referred to as "X direction"). In the present specification, the term "skin-facing surface" refers to the surface of the front and back surfaces of the members constituting the diaper 1A, such as the front sheet 2, which are disposed on the skin side of the wearer during wearing, and the so-called "non-skin pair" The "face" refers to the surface on the front and back sides of each member such as the front sheet 2 that faces the side opposite to the skin side of the wearer when worn.

As shown in Fig. 1, with respect to the diaper 1A, the left and right side edges of the front side region A and the left and right side edges of the back side region B are respectively outward in the width direction (X direction) toward the left and right side edges of the lower crotch region C. Extend. Further, the left and right side edges of the crotch region C are curved in an arc shape toward the inner side in the width direction (X direction), and have a shape in which the center portion in the longitudinal direction (Y direction) is narrowed toward the inside.

In the diaper 1A, as shown in Fig. 1, the front sheet 2 and the back sheet 3 are respectively extended outward from the left and right side edges and the front and rear end edges of the absorbent body 4 which are long in the longitudinal direction (Y direction). As shown in Fig. 1, the dimension of the front sheet 2 in the longitudinal direction (Y direction) is the same as the dimension of the back sheet 3 in the longitudinal direction (Y direction), but as shown in Fig. 2, the width direction (X direction) The size is smaller than the width direction (X direction) of the back sheet 3. The front sheet 2 and the back sheet 3 are joined to each other by the extension portions extending outward from the peripheral edge of the absorber 4, or by interposing other members, thereby sandwiching and fixing the absorber 4. The absorbent body 4 comprises: an absorbent core 41, which is obtained by holding particles of a water-absorbing polymer with an aggregate of fibers such as pulp fibers; and a core sheet 42 covering the absorbent core 41. The absorbent core 41 of the absorbent body 4 and the topsheet 2 will be described in detail below.

As shown in Fig. 1 and Fig. 2, each of the two sides of the diaper 1A in the longitudinal direction (Y direction) is provided with a sheet 36 for forming a three-dimensional gather having an elastic member 61 fixed in an extended state in the Y direction. And being fixed to the side of the front sheet 2, thereby forming a pair of three-dimensional pleats 6, 6 (refer FIG. 2). In addition, as shown in FIG. 1 and FIG. 2, in each of the both sides of the diaper 1A in the longitudinal direction (Y direction), the leg elastic members 63 for forming the leg gathers are arranged in an extended state in the Y direction. The leg gathers are formed by the contraction of the leg elastic members 63. Further, although not shown, a waist elastic member for forming a waist gather may be disposed at an end portion in the longitudinal direction (Y direction) of the back side region B side of the diaper 1A in the X direction, and the waist elastic member may be disposed by the waist portion. The elastic member contracts to form a waist fold.

As described above, the diaper 1A is a so-called unfolded type diaper, and as shown in Fig. 1, a pair of fastening tapes 7, 7 are provided on the left and right side edges of the back side region B, on the outer surface of the front side region A ( The non-skin facing surface is provided with a fixing band 8 for fixing the fastening tapes 7, 7.

In the first embodiment, the absorbent body 4 has the absorbent core 41. As shown in Figs. 1 and 3, the absorbent core 41 has a space portion 41s in which the pulp constituting the absorbent core 41 is not present. The space portion 41s of the absorbent core 41 included in the diaper 1A is attached to the crotch region C, and is a circle that protrudes inward from the both sides of the absorbent core 41 in the longitudinal direction (Y direction) toward the center line CL. It is formed by removing the pulp in an arc shape. Further, the absorbent core 41 included in the diaper 1A has a space portion 41s formed by removing pulp, but may have a low basis weight in which a plurality of pulp is laminated and the basis weight of the pulp is relatively low instead of the space portion 41s. . In the case of having a low basis weight portion, the basis weight of the low basis weight portion is preferably lower than that of other portions. Specifically, if the ratio of the low basis weight portion to the high basis weight portion is 70% or less, it is further preferred. If it is 50% or less, the effect that should be fully satisfied can be obtained. The absorbent body 4 included in the diaper 1A is covered with a single core sheet 42 and has an absorbent core 41 formed in an arc-shaped space portion 41s that protrudes inward. form.

When the front sheet 2 is described in detail, the top sheet 2 includes at least a fluffy non-woven fabric having a concavo-convex structure including a plurality of convex portions 21 raised on the opposite side of the skin and adjacent to the convex portion 21. The concave portion 22 of the recess. Further, as shown in FIG. 1 and FIG. 4, at least the pair of side sheets 5s and 5s in the longitudinal direction (Y direction) of the absorbent body 5 are disposed in the front sheet 2 except the back side region B. In the web convex portion region 9, the narrow convex portion region 9 includes a plurality of convex portions 21b having a width smaller than the width of the convex portion 21a having the largest width among the central portions 5m of the crotch region C. In the diaper 1A of the first embodiment, as shown in FIG. 1, the narrow convex portion region 9 is disposed in the crotch region C other than the back side region B except for the back side region B. That is, the narrow convex portion region 9 is disposed not only in the back side region B but also in the crotch region A, and is disposed in the crotch region C. The center portion 5m is a portion in which the center line CL is extended and the width (the length in the X direction) extending along the center line CL is about 70 mm in a state where the diaper 1A is stretched, and the both side portions 5s and 5s are tied to the diaper 1A. The narrowest portion in the width direction (X direction) of the lower region C is located outside the center portion 5m in the width direction (X direction). The side portions 5s, 5s, and the central portion 5m extend from the abdominal region A of the absorbent body 5 to the back region B, that is, the entire region in the longitudinal direction (Y direction). The convex portion 21a having the largest width may be the convex portion 21 in the region T of the central portion 5m of the crotch region C. In addition, the width (length in the X direction) of the convex portion 21 indicates the dimension in the X direction of the widest portion when the convex portion 21 is longitudinally sectioned in the vertical direction in the width direction (X direction).

The front sheet 2 of the diaper 1A is provided with a pair of narrow convex portion regions 9, 9 except for the pair of narrow convex portion regions 9, 9 which are the convex portions 21a having the largest width and width of all the convex portions 21. The width is roughly equal. Further, in the front sheet 2 of the diaper 1A, the width of all the convex portions is substantially equal to the convex portion 21b having a narrow width in the narrow convex portion region 9. That is, in the diaper 1A, the convex portion 21 includes the convex portion 21a having a wide width and the convex portion 21b having a narrow width. Further, commensurate with the convex portion 21, the concave portion 22 includes a concave portion 22b disposed in the narrow convex portion region 9, and a concave portion 22a disposed in a region other than the pair of narrow convex portion regions 9, 9. The total area of the narrow region of one pair of convex portions 9, 9 is preferably of 5cm ² or more, and further preferably 30cm ² or more, and is preferably 150cm ² or less, and further preferably 60cm ² or less, and more specifically, It is preferably 5 cm ² or more and 150 cm ² or less, and more preferably 30 cm ² or more and 60 cm ² or less. Further, the convex portion 21b having a narrow width disposed in the narrow convex portion region 9 may be uneven if the width thereof is smaller than the width of the convex portion 21a having the largest width.

In the first embodiment, the narrow convex portion region 9 is disposed at a position corresponding to the space portion 41s or the low basis weight portion of the absorbent core 41 constituting the absorbent body 4. Specifically, when the diaper 1A is viewed as shown in Fig. 1, a narrow convex shape having a shape similar to the contour is disposed in the range of the contours of the space portions 41s and 41s on both side portions of the absorbent core 41. Part area 9. In the diaper 1A, a pair of narrow convex portion regions 9 and 9 are disposed corresponding to the pair of space portions 41s and 41s. In other words, the space portion 41s of the absorbent core 41 is formed in an arc shape that protrudes inward from the side edge of the absorbent core 41 in the longitudinal direction (Y direction) toward the center line CL, and the shape of the space portion 41s. Similarly, the narrow convex portion region 9 of the front sheet 2 is also formed in an arc shape that protrudes inward from the side edge of the front sheet 2 in the longitudinal direction (Y direction) toward the center line CL.

In the diaper 1A, as viewed in FIG. 1, the side of the contour of the narrow convex portion region 9 is formed on the innermost side 90 to form an arc that protrudes inwardly to form a pair of narrow frames. The one side 90, 90 of the convex portion regions 9, 9 oppose each other. That is, the shape of one of the diapers 1A to the narrow convex portion regions 9, 9 is formed bilaterally symmetrically with respect to the center line CL.

The width W1 (refer to FIG. 2) of the convex portion 21a having the largest width is preferably 1 mm or more, further preferably 2 mm or more, and more preferably 30 mm or less, further preferably 5 mm or less, and more specifically, preferably 1 mm. The above is 30 mm or less, and more preferably 2 mm or more and 5 mm or less.

The width W2 (see FIG. 2) of the convex portion 21b having a narrow width in the narrow convex portion region 9 is preferably 0.5 mm or more, further preferably 1 mm or more, and preferably 20 mm or less. Further, it is preferably 4 mm or less, more specifically 0.5 mm or more and 20 mm or less, and further preferably 1 mm or more and 4 mm or less.

In the back sheet 2 of the diaper 1A, the width W2 of the narrow width portion 21b is smaller than the width W1 of the convex portion 21a having the largest width, and the width is the largest in terms of further improvement of the side leakage prevention. The width W1 of the convex portion 21a is 0.8 times or less, and more preferably 0.6 times or less.

In the diaper 1A, the width W4 of the concave portion 22b disposed in the narrow convex portion region 9 (the distance between the convex portions 21b and 21b adjacent to each other in the X direction) (see FIG. 2) is preferably 0.1 mm or more. Further, it is preferably 0.5 mm or more, more preferably 20 mm or less, further preferably 5 mm or less, and more preferably 0.1 mm or more and 20 mm or less, and further preferably 0.5 mm or more and 5 mm or less.

Further, in the diaper 1A, the width W3 (the distance between the convex portions 21a and 21a adjacent to each other in the X direction) of the concave portion 22a in the region other than the pair of the narrow convex portion regions 9 and 9 (see FIG. 2) is also smaller than The width or substantially equal width of the recess 22 disposed in the narrow convex portion region 9.

Further, when the diaper 1A is viewed as shown in Fig. 1, the maximum width W (see Fig. 1) of the narrow convex portion region 9 is formed to be wider than the width W2 of the convex portion 21b which is narrower in the width of the narrow convex portion 9 Wider.

The maximum width W of the narrow convex portion region 9 is preferably 2 mm or more, further preferably 5 mm or more, and more preferably 50 mm or less, further preferably 20 mm or less, and more specifically 2 mm or more and 50 mm or less. Further, it is preferably 5 mm or more and 20 mm or less.

The maximum width W of the narrow convex portion region 9 is preferably more than twice the width W2 of the convex portion 21b of the narrow convex portion region 9 from the viewpoint of further improvement of the side leakage preventing portion, and further preferably 5 More than double.

In the diaper 1A, the apparent density of the narrow convex portion region 9 is higher than the apparent density of the region including the convex portion 21a having the largest width among the central portions 5m of the underarm region C, Further, it is preferably 1.2 times or more, and more preferably 2 times or more, the apparent density of the region including the convex portion 21a having the largest width. The measurement of the apparent density is described in detail below.

<Method for measuring apparent density>

In the narrow-width convex portion region 9, the inside of the narrow-width convex portion region 9 is cut in the thickness direction to cut a portion of the range of 4 cm ² . Then, the cut thickness of each cut portion is measured using, for example, a KEYENCE VHX-1000 digital microscope at a magnification of 20 to 100 times and without load. Next, the apparent density of each of the cut portions was divided by the measured apparent thickness.

Similarly, in the region including the convex portion 21a having the largest width, the portion was cut in the thickness direction, and a portion of the range of 4 cm ^{2 was} cut out from the region, and the apparent density was measured.

The apparent density of the narrow convex portion region 9 is preferably 0.02 g/cm ³ or more, more preferably 0.03 g/cm ³ or more, and is preferably 0.1 g/cm ³ or less, and further preferably 0.07 g/cm ^{3 .} Hereinafter, more specifically, it is preferably 0.02 g/cm ³ or more and 0.1 g/cm ³ or less, and more preferably 0.3 g/cm ³ or more and 0.07 g/cm ³ or less.

The apparent density of the region including the convex portion 21a having the largest width is preferably 0.008 g/cm ³ or more, more preferably 0.02 g/cm ³ or more, and is preferably 0.05 g/cm ³ or less, and further preferably 0.04. It is preferably g/cm ³ or less, more specifically, 0.008 g/cm ³ or more and 0.05 g/cm ³ or less, and further preferably 0.02 g/cm ³ or more and 0.04 g/cm ³ or less.

As shown in FIG. 2 and FIG. 4, the uneven structure of the non-woven fabric constituting the front sheet 2 of the diaper 1A is a ridge structure, and the concave portion 22 is a groove structure. Each of the convex portion 21 and the concave portion 22 continuously extends in the longitudinal direction (Y direction), and the concave portion 22 is disposed between the convex portions 21 and 21 adjacent to each other in the width direction (X direction). When viewed in a cross-sectional view as shown in Fig. 2, the contour of the skin facing surface side of the front sheet 2 is the contour of the convex portion 21 protruding upward toward the skin facing surface side and the contour of the concave portion 22 toward the skin facing side. The contour of the lower projection is continuous in the width direction (X direction) and has a wave shape in the width direction (X direction). In the front sheet 2, there is no clear boundary between the convex portion 21 and the concave portion 22, and generally, two adjacent to each other in the width direction (X direction) The portion where the substantial thickness between the tops of the convex portions 21 and 21 is the smallest is the concave portion 22. In addition, the front sheet 2 of the diaper 1 shown in FIG. 2 has a undulating structure having a wavy shape on the skin facing surface side, and is not flat on the non-skin opposing side, but may have not only the skin facing side. The undulating shape of the waveform has a undulating structure of a waveform shape on the non-skin facing side.

In the front sheet 2 of the diaper 1A, the inside of the convex portion 21 is formed by filling the constituent fibers of the front sheet 2, and is a solid structure in which no voids are present inside. Further, the convex portion 21 and the concave portion 22 are different in the constituent fiber portions. Specifically, the convex portion 21 has a larger amount of constituent fibers than the concave portion 22. Since the convex portion 21 has a solid structure, the shape of the ridge portion can be prevented from being formed, and the contact area with the skin can be reduced to improve the wearing feeling. Moreover, the shape of the air and the like can be ensured without the shape of the concave and convex structure, and the skin problem caused by the stuffy heat can be reduced.

Further, in the front sheet 2 of the diaper 1A, a plurality of openings may be formed in the concave portion 22. It is preferable that the openings are regularly formed at regular intervals along the longitudinal direction (Y direction) in which the concave portions 22 extend. The shape of the opening can be formed into various shapes when the front sheet 2 is viewed in a plan view, and examples thereof include a circular shape, an elliptical shape, an oblong shape, a polygonal shape, and the like, or a combination of the shapes. The shape or size of the opening can be appropriately determined depending on the specific use of the front sheet 2. The size of the opening is preferably about 0.5 mm ² to 5 mm ^{2 in terms} of the projected area in a plan view from the viewpoint of the liquid permeability and the strength of the front sheet 2 . The opening is formed by separating the constituent fibers of the front sheet 2 more.

Further, in the front sheet 2 of the diaper 1A, the basis weight of the narrow convex portion region 9 is the same as the basis weight of the region including the convex portion 21a having the largest width among the central portions 5m of the crotch region C. That is, the basis weight of the entire front sheet 2 is uniform. The basis weight of the entire front sheet 2 is preferably 15 g/m ² or more, more preferably 20 g/m ² or more, and is preferably 150 g/m ² or less, further preferably 60 g/m ² or less, more specifically It is preferably 15 g/m ² or more and 150 g/m ² or less, and more preferably 20 g/m ² or more and 60 g/m ² or less.

The diaper 1A of the first embodiment is not particularly limited in its production method, and can be Manufactured by any method. Hereinafter, a preferred example of the method of manufacturing the diaper 1A of the first embodiment will be described with reference to Fig. 5 .

As shown in FIG. 5, it is performed using the pressure roller 100. The pressure roller 100 includes a first roller 102 that forms a pair of narrow convex portion regions 9 and a pair of convex regions 101 on the circumferential surface, and a second roller 103 whose circumferential surface is flat. One of the first rolls 102 is formed in a convex portion 101 at a position corresponding to one of the pair of space portions 41s, 41s or the low basis weight portion of the absorbent core 41 constituting the absorber 4, and is formed in the space portion. The contour of the 41s or low basis weight is similar in shape. Further, in the convex region 101, a plurality of convex portions (not shown) extending in the circumferential direction are provided at positions corresponding to the apexes of the convex portions 21 of the front sheet 2 of the uneven structure.

First, as the front sheet 2 of the diaper 1A, a front sheet as described in Japanese Laid-Open Patent Publication No. 2009-153937, which is hereby incorporated by reference.

Further, as the absorbent core 41 of the diaper 1A, an absorbent core in which a pair of space portions 41s, 41s or a low basis weight portion are formed by vacuuming according to a conventional method is used. The absorbent core 4 of the diaper 1A is formed by covering the thus formed absorbent core 41 having a pair of space portions 41s, 41s or a low basis weight by using one sheet of the core material 42.

Next, the strip-shaped front sheet 2 and the strip-shaped back sheet 3 are fixed by a conventional method in such a manner as to sandwich a plurality of absorbers 4, 4, which are intermittently supplied in the transport direction. Each of the both side portions of the belt-shaped front sheet 2 in the conveying direction is fixed in a conventional manner in a state in which the leg elastic members 63 are elongated in the conveying direction. Further, on the upper surface side of the strip-shaped front sheet 2 (the side on which the plurality of convex portions 21 are arranged), the strip-shaped three-dimensional shape is applied to both sides of the strip-shaped front sheet 2 in the transport direction. The sheet for forming the pleats 62 is fixed by a conventional method, and is fixed to the inner side in the width direction of each of the three-dimensional pleat-forming sheets 62 in a state in which the elastic members 61 for forming the three-dimensional pleats are elongated in the conveying direction.

A disposable diaper formed as described above is formed such that the upper surface side of the strip-shaped front sheet 2 (the side on which the plurality of convex portions 21 are disposed) faces the first roll 102 of the pressure roll 100 The continuous body 104 of 1A is transported between the first roll 102 and the second roll 103. Then, the continuous body 104 of the transported disposable diaper 1A is pressurized by a pair of convex regions 101. By pressurizing in this manner, the apex of the convex portion 21 of the front sheet 2 disposed at a position corresponding to the pair of the space portions 41s, 41s or the low basis weight portion is pressed in the circumferential direction, and the convex portion 21 is pressed by the one convex portion 21 Two convex portions 21b and 21b having narrow widths are formed. Further, the convex portion 21 located in a region other than the pair of convex regions 101 is not pressurized, and the original height of the convex portion 21 is maintained, thereby forming the convex portion 21a having a large width. In this manner, the convex portion 21 that maintains the original height of the convex portion 21 in a region other than the pair of convex regions 101 becomes the convex portion 21a having a large width, and the convex portion of the pair of convex regions 101 and the apex is pressurized. 21 becomes a convex portion 21b having a narrow width in a pair of narrow convex portion regions 9, 9. Through the above-described steps, the continuum 105 of the disposable diaper 1A including the strip-shaped front sheet 2 having a pair of narrow-width convex portions 9 and 9 intermittently in the conveying direction can be obtained by using the known one. The cutting mechanism cuts the continuous body 105 of the disposable diaper 1A, and the disposable diaper 1A can be continuously obtained. Further, when the first roller 102 and the second roller 103 of the pressure roller 100 are pressurized, they may be heated or may be pressurized at normal temperature.

Further, regarding the above-described manufacturing method of the disposable diaper 1A including the pair of narrow-width convex regions 9, 9, first, after the continuous body 104 of the disposable diaper 1A is manufactured, the first roller of the pressure roller 100 is used. Although the 102 and the second rolls 103 are pressurized, the first roll 102 and the second roll 103 of the press roll 100 may be used to pressurize only the strip-shaped front sheet 2, and may be intermittently arranged in the transport direction. A strip-shaped front sheet 2 having a pair of narrow-width convex regions 9, 9. Specifically, the strip-shaped front sheet 2 having the pair of narrow-width convex portions 9 and 9 which are formed in this manner may be disposed in a plurality of absorbent bodies 4 which are intermittently supplied in the transport direction. The absorbent core 41 has a position corresponding to the space portion 41s, 41s or the low basis weight portion, and the continuous body 105 of the disposable diaper 1A is formed in the above manner, and the formed portion is discarded by a known cutting mechanism. The continuum 105 of the diaper 1A is cut, whereby the disposable diaper 1A is continuously manufactured.

The material for forming the disposable diaper 1A of the first embodiment will be described.

The back sheet 3 and the three-dimensional pleat forming sheet 62 can be used without any particular limitation as long as they are generally used for absorbent articles such as disposable diapers. For example, as the back sheet 3, a resin film, a laminate of a resin film and a non-woven fabric, or the like can be used. As the three-dimensional pleat-forming sheet 62, a stretchable film, a nonwoven fabric, a woven fabric, or the like can be used.

The adhesive tape 7 can be used without any particular limitation as long as it is generally used for absorbent articles such as disposable diapers. For example, it is possible to use "MAGIC TAPE (registered trademark)" (manufactured by KURARAY Co., Ltd.), "QUICKLON (registered trademark)" (manufactured by YKK), "MAGICLOTH (registered trademark)" (manufactured by KANEBO BELL-TOUCH Co., Ltd.) Components, etc.

As the absorbent core 41 constituting the absorbent body 4, those in which the particles of the absorbent polymer are held by an aggregate of fibers such as pulp fibers can be used. As the covering material 42 constituting the absorber 4, a hydrophilic sheet such as a water-containing tissue (toilet paper) or a water-permeable nonwoven fabric can be used.

As the elastic member 61 for forming the three-dimensional pleats, the leg elastic member 63, and the waist elastic member, natural rubber, polyurethane, polystyrene-polyisoprene copolymer, polystyrene-poly can be used. A linear stretchable material such as a butadiene copolymer or a polyethylene-α-olefin copolymer such as ethyl acrylate-ethylene.

The adhesive for fixing the respective members is not particularly limited as long as it is generally used for absorbent articles such as disposable diapers, and for example, a hot-melt adhesive can be used. As the hot-melt adhesive, for example, styrene-isoprene-styrene block copolymer (SIS, Styrene-Isoprene-Styrene), styrene-butadiene-styrene block copolymer (SBS, Styrene) can be cited. -Butadiene-Styrene), a block copolymer of a styrene-ethylene-butylene-styrene copolymer (SEBS, Styrene-Ethylene-Butylene-Styrene).

The effect of the disposable diaper 1A of the embodiment of the present invention described above will be described.

In the diaper 1A, since the topsheet 2 is formed of a fluffy non-woven fabric having a concavo-convex structure, the cushioning property at the time of wearing is good, and the back bleed after the body fluid is absorbed is small, and the feeling of use is good. Further, as shown in Fig. 1, in the diaper 1A, since a pair of narrow convex portion regions 9, 9 are disposed in a portion other than the back side region B of the front sheet 2, it is easy to evacuate the back side region B, for example. The back side region B is diffused in the width direction (X direction), and is easily diffused sufficiently in the back side region B. Therefore, it is possible to suppress the amount of soft stool which is diffused to the crotch region C through the central region 5m, and the soft stool which diffuses to the crotch region C can be suppressed by the pair of narrow convex portions 9 and 9, and the prevention can be further enhanced. Soft side leakage.

In the diaper 1A, as shown in Fig. 3, the absorbent core 41 constituting the absorbent body 4 has a pair of space portions 41s and 41s, and is disposed at positions corresponding to the pair of space portions 41s and 41s as shown in Fig. 1 . There is a pair of narrow convex regions 9, 9. Therefore, for example, soft stools blocked by the narrow convex portion regions 9 and 9 are easily absorbed into the absorbent core 41 via the pair of space portions 41s and 41s, and the soft-proof leakage resistance can be further improved.

Further, as for the diaper 1A, as shown in Fig. 1, the narrow convex portion region 9 is disposed in the crotch region C except that the back side region B is excluded. Therefore, if the diaper 1A is brought into a pressurized state by packaging, the narrow convex portion region 9 is easily contracted in the width direction (X direction), and if it is to include such a contraction, the narrow convex portion regions 9, 9 When the diaper 1A is taken out and used, a higher anti-soft side leakage effect can be expected.

Further, as shown in FIGS. 2 and 4, the diaper 1A includes a fluffy non-woven fabric having a concavo-convex structure, and the concavo-convex structure has a plurality of ridges in which the convex portions 21 are ridges and the concave portions 22 are grooves. In the narrow convex portion region 9, the soft stool is easily diffused in the longitudinal direction (Y direction), and the side leakage preventing effect can be further improved.

Further, as for the front sheet 2 of the diaper 1A, as shown in Figs. 2 and 4, the apparent density of the narrow convex portion region 9 is higher than the area including the convex portion 21a having the largest width among the central portions 5m of the crotch region C. Since the viewing density is high, it is easy to block the soft stool which spreads in the width direction (X direction) in the crotch region C, and the effect of preventing the soft side leakage can be further improved.

Further, the diaper 1A is formed such that one of the pair of narrow convex portion regions 9, 9 is opposed to the center line CL, and one side 90, 90 is opposed to each other, and is formed in an arc shape convex toward the inner side, and is oriented toward the side. In the center of the lower area C, the diffusion width of the soft stool is narrowed. Therefore, the soft stool excreted in the back side region B is easily diffused to the central portion of the crotch region C through the central region 5m, and the effect of preventing the soft side leakage can be further enhanced.

Further, as for the diaper 1A, as shown in Fig. 1, the maximum width W of the narrow convex portion region 9 is formed larger than the width W2 of the convex portion 21b which is narrowed in the width of the narrow convex portion region 9. Therefore, the narrow convex portion region 9 can be easily formed, and the effect of preventing the soft side leakage can be further improved.

Next, a disposable diaper according to a second embodiment of the absorbent article of the present invention will be described with reference to Figs. 6 to 8 .

The disposable diaper 1B (hereinafter also referred to as "diaper 1B") of the second embodiment will be described as being different from the disposable diaper 1A of the first embodiment. The aspect which is not particularly described is the same as that of the diaper 1A, and the description of the diaper 1A is suitably applied.

As shown in Fig. 6, the diaper 1B is provided with a pair of narrow convex portion regions 9, 9 on the back sheet 2 in the same manner as the diaper 1A. The widths of all the convex portions 21 except for the pair of narrow convex portion regions 9, 9 are substantially equal to the width of the convex portion 21a having the largest width. Further, all of the widths of the convex portions 21b disposed in the narrow width of the narrow convex portion 9 are substantially equal.

In the diaper 1B, the width W5 (see FIG. 7) of the convex portion 21a having the largest width is preferably 1 mm or more, further preferably 2 mm or more, and more preferably 30 mm or less, further preferably 5 mm or less, and more specifically Preferably, it is 1 mm or more and 30 mm or less, More preferably, it is 2 mm or more and 5 mm or less.

Further, in the diaper 1B, the width W6 (see FIG. 7) of the convex portion 21b having a narrow width in the narrow convex portion region 9 is preferably 0.5 mm or more, further preferably 1 mm or more, and preferably 20 mm. Hereinafter, it is preferably 4 mm or less, more specifically 0.5 mm or more and 20 mm or less, and further preferably 1 mm or more and 4 mm or less.

In the front sheet 2 of the diaper 1B, the width W6 of the narrow width portion 21b is smaller than the width The width W5 of the convex portion 21a having the largest degree is preferably 0.8 times or less the width W5 of the convex portion 21a having the largest width, and more preferably 0.6 times or less from the viewpoint of further improving the side leakage prevention.

Further, as shown in Fig. 7 and Fig. 8, in the front sheet 2 of the diaper 1B, the width W8 of the concave portion 22b disposed in the narrow convex portion region 9 (the convex portions 21b and 21b adjacent to each other in the X direction) The interval (see FIG. 7) is formed to be smaller than the width W7 of the concave portion 22a in the region other than the pair of the narrow convex portion regions 9, 9, (the distance between the convex portions 21a and 21a adjacent to each other in the X direction) (refer to FIG. 7) ) or roughly equal.

In the diaper 1B, the width W8 of the concave portion 22b disposed in the narrow convex portion region 9 (the distance between the convex portions 21b and 21b adjacent to each other in the X direction) (see FIG. 7) is preferably 0.1 mm or more, and further preferably It is 0.5 mm or more, and is preferably 20 mm or less, more preferably 5 mm or less, and more preferably 0.1 mm or more and 20 mm or less, and further preferably 0.5 mm or more and 5 mm or less.

Further, in the diaper 1B, the width W7 of the concave portion 22a in the region other than the pair of the narrow convex portion regions 9, 9 (the distance between the convex portions 21a and 21a adjacent to each other in the X direction) is preferable (refer to Fig. 7). It is 0.1 mm or more, more preferably 0.3 mm or more, further preferably 10 mm or less, further preferably 3 mm or less, and more specifically, preferably 0.1 mm or more and 10 mm or less, and more preferably 0.3 mm or more. 3mm or less.

Further, when the diaper 1B is viewed as shown in Fig. 1, the maximum width W (see Fig. 6) of the narrow convex portion region 9 is formed to be larger than the width W6 of the convex portion 21b which is narrowed in the width of the narrow convex portion 9 . The maximum width W of the narrow convex portion region 9 is preferably more than twice the width W6 of the convex portion 21b of the narrow convex portion region 9 from the viewpoint of further improvement of the side leakage preventing portion, and further preferably 5 More than double.

In the diaper 1B, the apparent thickness of the narrow convex portion region 9 is smaller than the apparent thickness of the region including the convex portion 21a having the largest width among the central portions 5m of the crotch region C (see FIG. 7). Further, in the front sheet 2 of the diaper 1B, the basis weight of the narrow convex portion region 9 is formed to be high. The basis weight of the region including the convex portion 21a having the largest width among the central portions 5m of the crotch region C.

The apparent density of the narrow convex portion region 9 (the apparent density of the region including the convex portion 21a having the largest width) is preferably 0.02 g/cm ³ or more, more preferably 0.03 g/cm ³ or more, and further preferably 0.1. g / cm ³ or less, and further preferably 0.07g / cm ³ or less, and more specifically, preferably 0.02g / cm ³ or more and 0.1g / cm ³ or less, and further preferably 0.03g / cm ³ or more and 0.7 g/cm ³ or less.

The apparent density of the region including the convex portion 21a having the largest width is preferably 0.008 g/cm ³ or more, more preferably 0.02 g/cm ³ or more, and is preferably 0.05 g/cm ³ or less, and further preferably 0.04. It is preferably g/cm ³ or less, more specifically, 0.008 g/cm ³ or more and 0.05 g/cm ³ or less, and further preferably 0.02 g/cm ³ or more and 0.04 g/cm ³ or less.

The manufacturing method of the diaper 1B of the second embodiment is not particularly limited, and it can be produced by any method.

For example, one of the first rolls 102 of the press roll 100 shown in FIG. 5 can be manufactured by changing the convex region 101 as follows. Specifically, the design change may be performed by arranging a plurality of convex portions (not shown) provided in one of the first rolls 102 to the convex region 101 and extending in the circumferential direction. The absorbent core 41 constituting the absorbent body 4 has a position corresponding to the bottom of each concave portion 22 (groove) of the front sheet 2 of the uneven structure at the position corresponding to the space portions 41s and 41s or the low basis weight portion. When the pressure roller 100 having the convex portion (not shown) whose design is changed as described above is used, the diaper 1B can be manufactured in the same manner as the method of manufacturing the diaper 1A.

The disposable diaper 1B (hereinafter also referred to as "diaper 1B") of the second embodiment can exhibit the same effects as those of the disposable diaper 1A of the first embodiment, and the diaper 1A can be suitably used.

The disposable diaper according to one embodiment of the absorbent article of the present invention is not limited to the disposable diaper 1A of the first embodiment or the disposable diaper 1B of the second embodiment. The system can be changed as appropriate.

For example, in the disposable diapers 1A and 1B of the above-described embodiment, as shown in FIGS. 4 and 8, the convex portion 21 of the front sheet 2 continuously extends in the longitudinal direction (Y direction), but may be in the longitudinal direction ( The Y direction is arranged at intervals. In the case of being disposed at intervals, the length of the convex portion 21 is preferably 1 mm or more and 30 mm or less, and more preferably 2 mm or more and 5 mm or less. Further, in the case of being disposed at intervals, the length of the convex portion 21 located in the narrow convex portion region 9 is the same as the length of the convex portion 21 located in the region other than the narrow convex portion region 9. In addition, the length (length in the Y direction) of the convex portion 21 indicates the dimension in the Y direction of the longest portion when the convex portion 21 is longitudinally sectioned in the vertical direction in the longitudinal direction (Y direction).

Further, in the disposable diapers 1A and 1B of the above-described embodiment, as shown in Figs. 1, 3, and 6, the absorbent core 41 of the absorbent body 4 has a self-absorbent core in the crotch region C. A space portion 41s formed by removing the pulp in an arc shape in which the both side edges in the longitudinal direction (Y direction) are protruded toward the center line CL or a low basis weight portion in which the basis weight of the pulp is formed low. Alternatively, instead of the shape of the space portion 41s or the low basis weight portion of the absorbent core 41, as shown in FIG. 9, the space portion 41s or the low basis weight portion is located in the underarm region C in the absorbent core 41. The both sides of the longitudinal direction (Y direction) are further inside, and the shape is formed in an arc shape that protrudes inward toward the center line CL.

Moreover, as shown in FIG. 10, the space portion 41s or the low basis weight portion may have the first space portion 41s1 and the second space portion 41s2. Specifically, in the crotch region C, the first space portion 41s1 is formed in an arc shape in which the both sides of the absorbent core 41 project inward in the longitudinal direction (Y direction) toward the center line CL, and The second space portion 41s2 is located further inside than the arc-shaped top portion of the first space portion 41s1, and is formed in a pair of rectangular shapes.

Moreover, as shown in FIG. 11, the space portion 41s or the low basis weight portion may have the first space portion 41s1 and the third space portion 41s3. Specifically, in the crotch region C, the first space portion 41s1 is located further on the inner side of the longitudinal direction (Y direction) of the absorbent core 41, and is formed to be convex toward the center line CL. Out of an arc shape, and the third space portion 41s3 is located in the phase The arc-shaped tops of the adjacent first space portions 41s1 are formed in a rectangular shape in the middle of each other. In addition, as shown in FIG. 11, the end portion on the side of the back side region B is disposed on the back side of each of the first pair of arc-shaped first space portions 41s1 and 41s1. The end of the region B side is more biased against the ventral region A.

Further, as shown in FIG. 12, the space portion 41s or the low basis weight portion may be located on both sides in the longitudinal direction (Y direction) of the absorbent core 41, and the back side region B may be biased against the underarm region C. The portion is formed into a straight line through the entire area of the crotch region C and the ventral region A.

Further, in the disposable diapers 1A and 1B of the above-described embodiment, as shown in Figs. 1 and 6, the narrow convex portion region 9 of the front sheet 2 is disposed on the absorbent core 41 constituting the absorbent body 4. The space portion 41s or the low basis weight portion corresponds to the position, but may not be disposed correspondingly.

Further, in the disposable diapers 1A and 1B of the above-described embodiment, the shape of the space portion 41s or the low basis weight portion of the absorbent core 41 constituting the absorbent body 4 is as shown in FIG. The narrow convex portion region 9 of the front sheet 2 is disposed at a position corresponding to the space portion 41s or the low basis weight portion as shown in FIG. 1, FIG. 4, FIG. 6, and FIG. 8, but for example, in the space portion 41s. Or when the shape of the low basis weight is the shape shown in FIG. 9 above, the narrow convex portion region 9 of the front sheet 2 is as shown in FIG. 13, and the pair of space portions 41s, 41s shown in FIG. The shape of the low basis weight is similar, and in the underarm region C, the inner side edges of the absorbent core 41 in the longitudinal direction (Y direction) are further inside, and are formed to be convex toward the center line CL. Out of the arc.

Further, for example, when the space portion 41s or the low basis weight portion has the first space portion 41s1 and the second space portion 41s2 and is in the shape shown in FIG. 10, the front sheet may be as shown in FIG. The narrow-width convex portion region 2 has a pair of first narrow convex portion regions 9a and 9a at both side portions 5s and 5s, and a pair of central portions between the pair of first narrow convex portion regions 9a and 9a. Narrow convex regions 9b, 9b. Specifically, the narrow convex portion region 9 of the front sheet 2 is similar in shape to the pair of space portions 41s (the first space portion 41s1 and the second space portion 41s2) shown in FIG. Among the side portions 5s and 5s of the crotch region C, the pair of first narrow convex portion regions 9a and 9a are formed so as to be inward from the side edges of the front sheet 2 in the longitudinal direction (Y direction) toward the center line CL. a convex arc shape and between the pair of first narrow convex portion regions 9a, 9a, and further, the pair of central narrow convex portion regions 9b, 9b are located in a narrow arc-shaped narrow convex portion region 9a The top portion is further inside and formed into a rectangular shape that is long in the Y direction. In this case, as shown in Fig. 14, the end portions of the pair of central narrow-width convex portion regions 9b and 9b on the side of the back side region B are disposed in a pair of arc-shaped narrow convex portion regions 9a and 9a. The end portion on the side of the back side region B is more biased toward the ventral region A. Further, one of the narrow convex portion regions 9 of the front sheet 2 and the pair of space portions 41s (the first space portion 41s1 and the second space portion 41s2) shown in FIG. 10 may be one of the space portions. The shapes of 41s and 41s (the first space portion 41s1 or the second space portion 41s2) are similarly formed. For example, the shape of one of the pair of space portions 41s (the first space portion 41s1 and the second space portion 41s2) shown in FIG. 10 may be similar to the shape of the space portions 41s and 41s (the second space portion 41s2). As shown in Fig. 15, only a pair of central narrow-width convex portion regions 9b and 9b are formed in a rectangular shape that is long in the Y direction.

Further, for example, when the space portion 41s (the first space portion 41s1 and the third space portion 41s3) is in the shape shown in FIG. 11 described above, as shown in FIG. 16, the narrow sheet of the front sheet 2 may be used. The convex portion region 9 has a pair of first narrow convex portion regions 9a and 9a, and further has a second central narrow convex portion region 9c between the pair of first narrow convex portion regions 9a and 9a. Specifically, the narrow convex portion region 9 of the front sheet 2 may be similar in shape to the three spatial portions 41s (the first space portion 41s1 and the third space portion 41s3) shown in FIG. In the region C, the pair of first narrow convex portion regions 9a, 9a are located on the inner side of the longitudinal direction (Y direction) of the front sheet 2, and are formed to protrude inward toward the center line CL. The arcuate shape is between the pair of narrow convex portion regions 9a and 9a, and further, one second central narrow convex portion region 9c is located on the inner side of the arc-shaped narrow convex portion 9a. It is formed in a rectangular shape that is long in the Y direction. In this case, as shown in FIG. 16, the end portion of the side of the back side region B of the one second central narrow-width convex portion region 9c is located in a pair of arc-shaped narrow convex portions. The end portions on the side of the back side region B of each of the regions 9a and 9a are further to the front side region A. When the second central narrow-width convex portion region 9c is disposed in the abdomen region A of the pair of arc-shaped narrow convex portion regions 9a and 9a, the soft stool diffused to the underarm region C is easily in the underarm region. Further, C is diffused in the longitudinal direction (Y direction), so that side leakage in the crotch region C can be further prevented.

Further, for example, when the shape of the space portion 41s or the low basis weight portion is the shape shown in FIG. 12 described above, as shown in FIG. 17, the narrow convex portion region 9 of the front sheet 2 and the figure may be The space portion 41s or the low basis weight portion shown in FIG. 12 is similar in shape, and is formed on both sides in the longitudinal direction (Y direction) of the front sheet 2, and is passed from the portion of the back side region B which is biased to the underarm region C. The entire area of the crotch region C and the ventral region A is formed in a straight line. When the front sheet 2 shown in FIG. 17 is described in detail, the front sheet 2 has the convex portion 21a having the largest width in the central portion 5m of the crotch region C. Further, in the front sheet 2 other than the back side region B, a pair of side portions 5s and 5s in the longitudinal direction (Y direction) of the absorbent main body 5 are disposed with a pair of widths including the convex portions 21a having a width smaller than the maximum width. A narrow convex portion region 9 of a plurality of convex portions 21b.

Further, in the disposable diapers 1A and 1B of the above-described embodiment, as the front sheet 2, as shown in Figs. 2 and 7, a ridge having a solid convex portion 21 as a ridge and a concave portion 22 as a groove may be used. In addition to the non-woven fabric of the concave-convex structure of the groove structure, two layers having the first layer and the second layer may be used, and the first layer side may be swelled on the opposite surface side of the skin to form a cavity. A plurality of convex portions 21 and a fluffy non-woven fabric having a concave-convex structure of the concave portion 22 are formed between the adjacent convex portions 21. As such a nonwoven fabric, for example, a front sheet described in Japanese Laid-Open Patent Publication No. 2004-174234, which is hereby incorporated by reference. Further, instead of the non-woven fabric including the uneven structure of the above-described ridge groove structure, a woven fabric composed of two layers and having a plurality of convex portions having a solid interior and a concave-convex structure between the convex portions may be used. As such a nonwoven fabric, for example, a front sheet described in Japanese Laid-Open Patent Publication No. 2002-187228, which is hereby incorporated by reference. Further, instead of the non-woven fabric having the uneven structure of the above-described ridge structure, it may be composed of one layer and A fluffy non-woven fabric having a plurality of convex portions that are raised on the opposite side of the skin and a concave-convex structure of the concave portion between the convex portions. As such a nonwoven fabric, for example, a front sheet described in Japanese Laid-Open Patent Publication No. 2012-136790, which is hereby incorporated by reference.

Further, as a method of manufacturing the disposable diapers 1A and 1B of the above-described embodiment, a pressure roller 100 having a first roller 102 including a pair of narrow convex portion regions 9 and a pair of narrow convex portion regions 11 on the circumferential surface is used. An example of manufacturing is carried out, but the press roll 100 may not be used. For example, a plurality of absorbent bodies 4, 4, which are intermittently supplied in the transport direction, are fixed to the strip-shaped front sheet 2 in accordance with a conventional method, and the strip-shaped front sheet 2 to which the absorbent body 4 is fixed is conveyed. The belt-like back sheet 3 is sandwiched between the plurality of absorbers 4 and 4 in a state in which the tension is applied in the conveying direction only in a portion where the pair of narrow-width projection portions 9 are to be formed. The way of ... is fixed according to the conventional method. By performing the necking in this manner, the narrow convex portion region 9 can be formed. After the front sheet 2 is formed into the narrow convex portion region 9, the upper surface side of the strip-shaped front sheet 2 (the side on which the plurality of convex portions 21 are disposed) is transported along the strip-shaped front sheet 2 Each of the two sides of the direction is fixed to the strip-shaped three-dimensional pleat-forming sheet 62, and the elastic member 61 for forming the three-dimensional pleats is transported on the inner side in the width direction of each of the three-dimensional pleat-forming sheets 62. The state in which the direction is elongated is fixed in accordance with a conventional method. Through the above-described steps, a continuum of the disposable diapers 1A, 1B including the strip-shaped front sheet 2 having a pair of narrow-width convex regions 9, 9 intermittently in the conveying direction can be obtained by using the known The cutting mechanism cuts the continuous body of the disposable diapers 1A and 1B, and continuously obtains the disposable diapers 1A and 1B.

Further, as shown in Fig. 1 and Fig. 6, the disposable diapers 1A and 1B of the above-described embodiment are unfolded disposable diapers, but may be a pants-type disposable diaper or a menstrual sanitary napkin.

Regarding the above embodiment, the following absorbent article is further disclosed.

<1> an absorbent article having a vertically long absorbent body, the above absorbent body a front sheet comprising a liquid permeable property disposed on the opposite side of the skin, a back sheet disposed on the non-skin facing side, and an absorbent member disposed between the two sheets; The sexual body is divided into a ventral region on the ventral side of the wearer when worn, a back side region on the back side, and a crotch region disposed between the ventral region and the dorsal region, the front sheet being at least a fluffy non-woven fabric having a concavo-convex structure, wherein the concavo-convex structure includes a plurality of convex portions that are raised on the opposite side of the skin and a concave portion that is adjacent to the concave portion, and the front sheet except the back side region At least two pairs of narrow convex portion regions are disposed on both side portions of the absorbent body in the longitudinal direction, and the narrow convex portion region includes a plurality of widths having a width smaller than a width of a convex portion having a largest width at a central portion of the crotch region Convex.

<2> The absorbent article according to the above <1>, wherein the absorbent body has a low basis weight portion having a relatively low basis weight of the pulp constituting the absorbent body, or a space portion having no pulp constituting the absorbent body, The narrow convex portion region is disposed at a position corresponding to the low basis weight portion or the space portion.

<3> The absorbent article according to the above <1>, wherein the narrow convex portion region is not present in the abdominal region and is disposed in the underarm region.

<4> The absorbent article according to the above <1>, wherein the front sheet has a convex portion having the largest width at a central portion of the crotch region, and the front sheet other than the back side region is In the above absorbent body At least two pairs of narrow convex regions including a plurality of convex portions having a width smaller than the width of the convex portion having the largest width are disposed at both side portions in the longitudinal direction.

The absorbent article according to any one of the above aspects, wherein the uneven structure of the non-woven fabric constituting the front sheet is a ridge structure in which the convex portion is a ridge and the concave portion is a groove.

The absorbent article according to any one of the above aspects, wherein the narrow-width convex portion has a higher apparent density than the convex portion having the largest width among the central portions of the underarm region. The apparent density.

The absorbent article according to any one of the above aspects, wherein the side of the outline of the narrow convex portion region is disposed on the innermost side and is formed inward in a plan view. The convex arc shape forms the one side of the pair of narrow convex portion regions facing each other.

The absorbent article according to any one of the above aspects, wherein the narrow width of the narrow convex portion is larger than the width of the narrow convex portion in a plan view. The width of the convex part.

The absorbent article according to any one of the above-mentioned <1> to <8> wherein, between the pair of narrow convex portion regions, at least one central narrow convex portion region is further disposed, the center is narrow The end portion on the side of the back side region of the web convex portion is disposed on the side of the back side region of each of the pair of narrow convex portion regions more toward the ventral region.

The absorbent article of any one of the above-mentioned <1> to <9> wherein the above absorption The item is a disposable diaper.

<11> The absorbent article according to the above <10>, wherein the disposable diaper is an unfolded disposable diaper, and a pair of fastening tapes are provided on the left and right side edges of the back side region, and the outer surface of the ventral region is provided. A fixing strap for fixing the fastening tape is provided.

<12> The absorbent article according to the above <10>, wherein the liquid-impermeable back sheet comprises a liquid-impermeable film and a non-woven fabric disposed outside.

<13> The absorbent article according to the above <12>, wherein the outer covering body has a retracted position, and the retracted position is provided in the crotch region.

The absorbent article according to any one of the above aspects, wherein the absorbent body comprises an absorbent core obtained by holding particles of a water-absorbing polymer in an aggregate of pulp fibers, and coating the absorbent core A coated core material of an absorbent core.

The absorbent article according to any one of the above-mentioned <10>, wherein the both sides of the disposable diaper in the longitudinal direction have a three-dimensional fold of the elastic member fixed in an elongated state. The forming sheet is disposed and fixed to the side portion of the front sheet, thereby forming a pair of three-dimensional pleats.

The absorbent article according to any one of the above-mentioned <10>, wherein the leg elastic members for forming the leg gathers are elongated at both sides in the longitudinal direction of the disposable diaper. The state configuration forms leg pleats by contraction of the leg elastic members.

<17> The absorbent article according to any one of <10> to <16> wherein the above absorption The body has an absorbent core having a space portion in which no pulp constituting the absorbent core is present, and the space portion of the absorbent core included in the disposable diaper is attached to the underarm region The both sides of the absorbent core are formed by removing the pulp in an arc shape in which the both side edges in the longitudinal direction (Y direction) are convex toward the center line CL.

<18> The absorbent article according to the above <17>, wherein the space portion has a low basis weight in which pulp is laminated and the basis weight of the pulp is relatively low, and the basis weight of the low basis weight is a low basis weight/ The ratio of the high basis weight is 70% or less, preferably 50% or less.

The absorbent article according to the above <17>, wherein the absorbent system is coated with a coated core material and has an absorbent core formed in an arc-shaped space portion or a low basis weight which is formed to protrude inward. And formed.

The absorbent article according to any one of the above aspects, wherein the front sheet is attached to both sides of the absorbent body in the longitudinal direction (Y direction), and at least one pair is disposed. a narrow convex portion region of a plurality of convex portions having a width smaller than a width of a convex portion having a largest width among the central portions of the crotch region, the narrow convex portion region being a portion disposed in the underarm region and a central portion for diapers In the state of being stretched, the center line is extended along the center line, and the both sides are the narrowest portion in the width direction (X) direction of the crotch region of the diaper, and are located on the outer side in the width direction (X direction) from the center portion. The both side portions and the central portion are respectively spread from the ventral region of the absorbent body over the back side region, that is, the entire length direction (Y direction).

The absorbent article according to any one of the items <10>, wherein the front sheet is provided with a pair of narrow convex portion regions, and all convex portions other than the pair of narrow convex portion regions The width of the portion is equal to the width of the convex portion having the largest width, and the width of the convex portion disposed in the narrow convex portion region of the front sheet is uniform, and the concave portion includes the concave portion disposed in the narrow convex portion region. And a recessed portion in a region other than the pair of narrow-width convex regions, the total area of the pair of narrow-width convex regions is 5 cm ² or more, preferably 30 cm ² or more, and 150 cm ² or less, preferably 60 cm ² Hereinafter, it is preferably 5 cm ² or more and 150 cm ² or less, and more preferably 30 cm ² or more and 60 cm ² or less.

The absorbent article according to any one of the above aspects, wherein the front sheet is disposed on the innermost side of the side of the outline of the narrow convex portion in a plan view. Formed to be arcuately convex toward the inner side, the one side of the pair of narrow convex portion regions are opposed to each other, and the shape of the pair of the narrow convex portion regions is formed bilaterally symmetrically with respect to the center line, and the width is the largest The width W1 of the convex portion is 1 mm or more, preferably 2 mm or more, and is 30 mm or less, preferably 5 mm or less, preferably 1 mm or more and 30 mm or less, more preferably 2 mm or more and 5 mm or less, and is disposed in a narrow range. The width W2 of the convex portion having a narrow width in the convex portion region is 0.5 mm or more, preferably 1 mm or more, and 20 mm or less, preferably 4 mm or less, preferably 0.5 mm or more and 20 mm or less, and further preferably 1 mm. Above and below 4mm.

The absorbent article according to any one of the above-mentioned <10>, wherein the width W2 of the convex portion having a narrow width is smaller than the width W1 of the convex portion having the largest width, and is The width W1 of the convex portion having the largest width is 0.8 times or less, preferably 0.6 times or less.

The absorbent article according to any one of the above-mentioned <10>, wherein the width W4 of the concave portion disposed in the narrow convex portion region (the convex portions 21b and 21b adjacent to each other in the X direction are spaced apart from each other) The thickness is 0.1 mm or more, preferably 0.5 mm or more, and is 20 mm or less, preferably 5 mm or less, preferably 0.1 mm or more and 20 mm or less, and more preferably 0.5 mm or more and 5 mm or less.

The absorbent article according to any one of the above-mentioned <10>, wherein the maximum width W of the narrow convex portion is formed larger than that of the narrow convex portion when the front sheet is viewed from above. The width W2 of the narrow width portion and the maximum width W of the narrow convex portion region are 2 mm or more, preferably 5 mm or more, and 50 mm or less, preferably 20 mm or less, preferably 2 mm or more and 50 mm or less. It is preferably 5 mm or more and 20 mm or less.

The absorbent article according to any one of the items <10>, wherein the maximum width W of the narrow convex portion region is more than twice the width W2 of the convex portion disposed in the narrow convex portion region. Preferably, it is 5 times or more.

The absorbent article according to any one of the above aspects, wherein the narrow convex portion has a higher apparent density than the convex portion having the largest width among the central portions of the underarm region. The apparent density is 1.2 times or more, preferably 2 times or more, the apparent density of the region including the convex portion having the largest width.

The absorbent article according to any one of the above aspects, wherein the narrow convex portion has an apparent density of 0.02 g/cm ³ or more, preferably 0.03 g/cm ³ or more, and It is 0.1 g/cm ³ or less, preferably 0.07 g/cm ³ or less, preferably 0.02 g/cm ³ or more and 0.1 g/cm ³ or less, and more preferably 0.3 g/cm ³ or more and 0.07 g/cm. ³ or less, the apparent density of the region including the convex portion having the largest width is 0.008 g/cm ³ or more, preferably 0.02 g/cm ³ or more, and 0.05 g/cm ³ or less, preferably 0.04 g/cm ^{3 .} Hereinafter, it is preferably 0.008 g/cm ³ or more and 0.05 g/cm ³ or less, and more preferably 0.02 g/cm ³ or more and 0.04 g/cm ³ or less.

<29> The absorbent article according to any one of the above aspects, wherein the uneven structure of the non-woven fabric constituting the front sheet is a ridge, and the concave portion is a groove structure of the groove, and the convex portion and the concave portion are both in length. The direction (Y direction) is continuously extended, and concave portions are disposed between the convex portions adjacent to each of the width directions (X directions), and the contour of the skin facing surface side of the front sheet is a cross-sectional view, and the convex portion is The contour which protrudes toward the upper side of the skin facing surface side and the contour which protrudes below the skin facing surface side of the concave portion are continuous in the width direction (X direction), and have a wave shape in the width direction (X direction).

<30>

The absorbent article according to any one of the above-mentioned <10>, wherein, in the front sheet, a portion having a minimum thickness between the tops of the two convex portions adjacent in the width direction (X direction) It has a structure in which the concave portion is formed in a wavy shape on the opposite side of the skin, and the non-skin facing surface side is flat or has a undulating shape.

<31>

The absorbent article according to any one of the above-mentioned <10>, wherein in the front sheet, the inside of the convex portion is formed by filling the constituent fibers of the front sheet, and there is no void inside. In the solid structure, the amount of fibers is different between the convex portion and the concave portion, and the amount of constituent fibers of the convex portion is larger than the amount of constituent fibers of the concave portion.

<32>

The absorbent article according to any one of the items <10>, wherein the front sheet is formed in a plurality of openings in the concave portion, and the openings are spaced apart in the longitudinal direction (Y direction) in which the concave portion extends. Formed regularly at intervals, and the shape of the opening is a shape of a circle, an ellipse, an oblong shape, a polygonal shape, or a combination of the shapes when the front surface sheet is viewed from the top, The size of the opening is 0.5 mm ² to 5 mm ² in a plan view area in a plan view.

<33>

The absorbent article according to any one of the items <10> to <32> wherein The basis weight of the narrow concave portion of the sheet is the same as the basis weight of the region including the convex portion having the largest width among the central portions of the underarm region, and the basis weight of the entire front sheet is uniform.

<34>

The absorbent article according to any one of the items <10> to <33> wherein the entire front sheet has a basis weight of 15 g/m ² or more, preferably 20 g/m ² or more, and 150 g/m ^{2 .} Hereinafter, it is preferably 60 g/m ² or less, preferably 15 g/m ² or more and 150 g/m ² or less, and more preferably 20 g/m ² or more and 60 g/m ² or less.

<35>

The absorbent article according to any one of the above aspects, wherein the back sheet is a resin film or a laminate of a resin film and a non-woven fabric, and the sheet for forming a three-dimensional pleat is a stretchable film or a non-woven fabric. a laminated sheet of fabric or the like.

<36>

The absorbent article according to any one of the above-mentioned items, wherein the absorbent core constituting the absorbent body is formed by using particles of a fiber such as pulp fibers to hold particles of a water-absorbent polymer. The coating material constituting the absorbent body is a hydrophilic sheet, and either a packaged core material containing a water-permeable tissue (toilet paper) or a coated core material containing a water-permeable nonwoven fabric is used.

Example

Hereinafter, the present creation will be described in further detail by way of examples. However, the scope of the present creation is not limited by this embodiment.

[Example 1]

By using the MOONY (registered trademark) M code of UNICHARM Co., Ltd., the tension is applied to the longitudinal direction only in the portion of the front sheet which is disposed at a position corresponding to the space portion of the absorbent core constituting the absorbent body. Partially necked, a disposable diaper of Example 1 having a pair of narrow raised edge regions 9, 9 was made. The shape of the pair of narrow convex portion regions 9 and 9 is formed in an arc shape that protrudes inward from the side edge of the front sheet in the longitudinal direction (Y direction) toward the center line CL. The total area of the pair of narrow-width convex regions 9, 9 is 30 cm ² . The width of the convex portion 21b having a narrow width in the narrow convex portion region 9 is 2 mm, and the width of the convex portion (the convex portion 21a having the largest width) in the region other than the narrow convex portion region 9 is 3 mm. The narrow width of the narrow convex region 9 is 20 mm. The apparent density of the narrow convex portion region 9 was 0.032 g/cm ³ , and the apparent density of the region other than the narrow convex portion region 9 was 0.020 g/cm ³ .

[Comparative Example 1]

No tension was applied, and the MOONY (registered trademark) M code of UNICHARM Co., Ltd. was directly used as the disposable diaper of Comparative Example 1.

[Comparative Example 2]

Using the MOONY (registered trademark) M code of UNICHARM Co., Ltd., tension is applied to the longitudinal direction of both sides of the front sheet in the longitudinal direction (Y direction), so that the portion is shrunk and the length is made over both sides. A disposable diaper of Comparative Example 2 in which a pair of narrow convex portion regions were disposed in the entire direction (Y direction).

[Comparative Example 3]

Using the MOONY (registered trademark) M code of UNICHARM Co., Ltd., the entire region of the front sheet was subjected to tension in the longitudinal direction (Y direction), and a disposable diaper of Comparative Example 3 in which the entire region became a narrow convex portion was produced.

[Performance Evaluation]

With respect to the disposable diapers of Example 1 and Comparative Examples 1 to 3, the diffusibility of the soft stool at the time of wearing was evaluated by the following method. The evaluation environment was room temperature 23 ° C and humidity 50% RH. The results of these and the like are shown in Table 1 below.

[Diffuse when wearing]

In the disposable diaper obtained in Example 1 and Comparative Examples 1 to 3, 10 g of simulated soft stool was injected through the tube at the central portion of the back side region of the skin facing surface side of the front sheet. The simulated soft stool was composed of 28.0 g of bentonite, 14.0 g of glycerin, 114.1 g of ion-exchanged water, and an aqueous solution (Kao) of 14.3 wt% of EMULGEN 130K, and the viscosity was 300mPa. s (23 ° C, vibrating viscometer: SV-10 manufactured by A&D Co., Ltd.).

After the injection, an OHP (Overhead Projector) film was placed on the front sheet, and a roll having a diameter of 65 mm and a width of 65 mm was used from the OHP film to measure the roll toward the ventral region. The diffusion width and the diffusion distance from the injection point to the ventral region. In the measurement, three samples were measured for each diaper, and the average value of the measured values was determined and shown in Table 1.

As is clear from the results shown in Table 1, it is understood that the disposable diaper of Example 1 can promote the diffusion in the longitudinal direction of the underarm region as compared with the disposable diapers of Comparative Examples 1 to 3, and can suppress the direction. Diffusion in the width direction. Therefore, according to the disposable diaper of the first embodiment, it is expected to effectively prevent the side leakage of the soft stool.

On the other hand, it is understood that the disposable diaper of Comparative Example 1 is likely to diffuse in the width direction in the underarm region because there is no narrow convex portion region. Further, in the disposable diaper of Comparative Example 2, since the pair of narrow convex portion regions exist over the entire region in both sides in the longitudinal direction, the diffusion into the crotch region is excessively promoted, and the diffusion is also spread in the width direction. Further, in the disposable diaper of Comparative Example 3, since the entire region is a narrow convex portion region, it is easy to diffuse in the longitudinal direction, and it is easy to diffuse in the width direction in the underarm region.

[Industrial availability]

According to the absorbent article of the present invention, the cushioning property at the time of wearing is good, and the rewet after the absorption of the body fluid is small, the feeling of use is good, and the leakage resistance against body fluid is further improved.

1A‧‧‧ diapers

2‧‧‧Front sheet

3‧‧‧Back sheet

4‧‧‧Acceptor

5‧‧‧Absorbing ontology

5m‧‧‧Central Department

5s‧‧‧ side

6‧‧‧Three-dimensional folds

7‧‧‧Buckle belt

8‧‧‧Fixed tape

9‧‧‧Narrow convex area

21‧‧‧ convex

21a‧‧‧ convex

21b‧‧‧ convex

22‧‧‧ recess

22a‧‧‧ recess

22b‧‧‧ recess

41‧‧‧Absorbable core

41s‧‧‧ Space Department

42‧‧‧Package

61‧‧‧Flexible components

62‧‧‧Three-dimensional pleat forming sheet

63‧‧‧ Leg elastic members

90‧‧‧ side

A‧‧‧ Ventral area

B‧‧‧Back side area

C‧‧‧胯下区域

CL‧‧‧ center line

T‧‧‧ area

W‧‧‧Maximum width

X‧‧‧ direction

Y‧‧‧ direction

Claims (36)

An absorbent article comprising a vertically long absorbent body, wherein the absorbent body comprises a liquid-permeable front sheet disposed on the opposite side of the skin, and a liquid-impermeable back surface disposed on the non-skin facing surface side. a sheet and an absorber disposed between the two sheets, wherein the absorbent body is divided into a ventral region on the ventral side of the wearer when worn, a back region on the back side, and a ventral side In the underarm region between the region and the back side region, the front sheet includes at least a fluffy non-woven fabric having a concavo-convex structure, and the concavo-convex structure includes a plurality of convex portions raised on the opposite side of the skin and adjacent to the convex portion a recessed portion, wherein the front sheet other than the back side region is provided with at least a pair of narrow convex portion regions on both sides in the longitudinal direction of the absorbent body, wherein the narrow convex portion includes a width smaller than a plurality of convex portions having a width of the convex portion having the largest width at the central portion of the crotch region. The absorbent article of claim 1, wherein the absorbent body has a low basis weight having a relatively low basis weight of the pulp constituting the absorbent body, or a space portion having no pulp constituting the absorbent body, which is lower than the above The narrow convex portion region is disposed at a position corresponding to the basis weight portion or the space portion. The absorbent article of claim 1, wherein the narrow convex portion region is not present in the abdominal region and is disposed in the underarm region. The absorbent article of claim 1, wherein the front sheet has a convex portion having a largest width at a central portion of the crotch region, and the front sheet other than the back side region is on the absorptive body At least two pairs of narrow convex portion regions are disposed on both side portions in the longitudinal direction, and the narrow convex portion region includes a plurality of convex portions having a width smaller than a width of the convex portion having the largest width. The absorbent article according to claim 1, wherein the uneven structure of the non-woven fabric constituting the front sheet is a ridge structure in which the convex portion is a ridge and the concave portion is a groove. The absorbent article of claim 1, wherein the narrow density of the convex portion region is higher than the visual density of the region of the central portion of the underarm region including the convex portion having the largest width. The absorbent article according to claim 1, wherein in the plan view, the side of the contour of the narrow convex portion is disposed on the innermost side to form an arc that protrudes inwardly to form the pair of narrow frames. The one side of the convex portion faces each other. The absorbent article of claim 1, wherein the maximum width of the narrow convex portion region is larger than the width of the convex portion having the narrow width disposed in the narrow convex portion region in plan view. The absorbent article of claim 1, wherein at least one central narrow convex portion region is disposed between the pair of narrow convex portion regions, and an end portion of the central narrow convex portion region on the side of the back side region The end portion on the side of the back side region of each of the pair of narrow convex portion regions is disposed more toward the ventral region. The absorbent article of claim 1, wherein the absorbent article is a disposable diaper. The absorbent article of claim 10, wherein the disposable diaper is an unfolded disposable diaper, and a pair of fastening strips are disposed on the left and right side edges of the back side region, and the outer surface of the ventral region is provided with A fastening strap that is fastened to the fastening tape. The absorbent article according to claim 10, wherein the liquid-impermeable back sheet comprises an outer covering comprising a liquid-impermeable film and a non-woven fabric disposed on the outer side. The absorbent article of claim 12, wherein the outer covering has a retracted position, The retracted position is in the underarm region. The absorbent article according to claim 10, wherein the absorbent body comprises an absorbent core in which particles of the water-absorbing polymer are held by an aggregate of pulp fibers, and a coated core material covering the absorbent core. The absorbent article according to claim 10, wherein each of the both sides of the disposable diaper in the longitudinal direction is disposed and fixed to the front sheet of the sheet for forming a three-dimensional pleat having an elastic member fixed in an extended state. The sides are formed thereby forming a pair of three-dimensional pleats. The absorbent article of claim 10, wherein the leg elastic members for forming the leg gathers are disposed in an extended state on both sides of the disposable diaper in the longitudinal direction, and the leg elastic members are contracted. Form leg folds. The absorbent article of claim 10, wherein the absorbent body has an absorbent core having a space portion in which no pulp constituting the absorbent core is present, and the absorbent core included in the disposable diaper The space portion is formed in the underarm region, and is formed by removing the pulp in an arc shape in which the both sides of the absorbent core are protruded inward in the longitudinal direction (Y direction) toward the center line CL. The absorbent article of claim 17, wherein the space portion has a low basis weight in which pulp is laminated and the basis weight of the pulp is relatively low, and the basis weight of the low basis weight is a low basis weight/high basis weight The ratio is 70% or less. The absorbent article according to claim 17, wherein the absorbent system is formed by coating an absorbent core having an arc-shaped space portion or a low basis weight which is formed to protrude inward by a clad chip material. The absorbent article of claim 10, wherein the front sheet is attached to both sides of the absorbent body in the longitudinal direction (Y direction), and at least one pair of narrow convex portions are disposed, the narrow convex portion including the width a plurality of convex portions having a width smaller than a width of a convex portion having the largest width among the central portions of the underarm region, the narrow convex portion region being as follows: The central portion is placed in the underarm region, and the central portion includes a center line extending along the center line in a state in which the diaper is stretched, and the both sides are located at the center in the width direction (X direction) of the lower portion of the diaper. The portion is further outward in the width direction (X direction); the both side portions and the central portion are respectively spread from the ventral region of the absorbent body over the back side region, that is, the entire length direction (Y direction). The absorbent article of claim 10, wherein the front sheet is provided with a pair of narrow convex portion regions, and the widths of all the convex portions of the regions other than the pair of narrow convex portion regions are equal to the width of the convex portion having the largest width The width of the convex portion disposed in the narrow convex portion region of the front sheet is uniform, and the concave portion includes a concave portion disposed in the narrow convex portion region and a region other than the pair of narrow convex portions. The area of the concave portion of the region, the total area of the pair of narrow convex portions is 5 cm ² or more and 150 cm ² or less. The absorbent article according to claim 10, wherein the front sheet is formed in an arc shape which is formed on the innermost side of the contour of the narrow convex portion in a plan view, and is formed in an arc shape. The one side of the narrow convex portion region faces each other, and the shape of the pair of the narrow convex portion regions is formed bilaterally symmetrically with respect to the center line, and the width W1 of the convex portion having the largest width is 1 mm or more and 30 mm or less. The width W2 of the convex portion having a narrow width in the narrow convex portion region is 0.5 mm or more and 20 mm or less. The absorbent article according to claim 10, wherein in the front sheet, the width W2 of the narrow width portion is smaller than the width W1 of the convex portion having the largest width, and is 0.8 times or less the width W1 of the convex portion having the largest width. . The absorbent article according to claim 10, wherein the width W4 (the distance between the convex portions adjacent to each other in the X direction) of the concave portion disposed in the narrow convex portion region is 0.1 mm or more and 20 mm or less. The absorbent article of claim 10, wherein the narrow sheet is viewed from above the top sheet The maximum width W of the convex portion region is formed to be larger than the width W2 of the convex portion having a narrow width in the narrow convex portion region, and the maximum width W of the narrow convex portion region is 2 mm or more and 50 mm or less. The absorbent article of claim 10, wherein the maximum width W of the narrow convex portion region is more than twice the width W2 of the convex portion disposed in the narrow convex portion region. The absorbent article of claim 10, wherein the narrow density of the convex region is higher than the visual density of the region of the central portion of the underarm region having the largest width, and is the convex portion having the largest width. The apparent density of the area is 1.2 times or more. The absorbent article according to claim 10, wherein the narrow-density convex portion has an apparent density of 0.02 g/cm ³ or more and 0.1 g/cm ³ or less, and the visual density of the region including the convex portion having the largest width is 0.008 g/ Cm ³ or more and 0.05 g/cm ³ or less. The absorbent article according to claim 10, wherein the uneven structure of the non-woven fabric constituting the front sheet is a ridge and the concave portion is a groove structure of the groove, and the convex portion and the concave portion are continuously extended in the longitudinal direction (Y direction). A concave portion is disposed between each of the convex portions adjacent to each other in the width direction (X direction), and the contour of the skin facing surface side of the front sheet is in a cross-sectional view, and the convex portion is above the opposite side of the skin. The outline of the convex portion and the contour of the concave portion protruding downward from the opposite side of the skin are continuous in the width direction (X direction), and have a wave shape in the width direction (X direction). The absorbent article according to claim 10, wherein in the front sheet, a portion having a minimum thickness between the tops of the two convex portions adjacent in the width direction (X direction) is a concave portion and becomes a skin opposite direction. The surface side has a undulating structure of a wave shape, and the non-skin facing surface side is flat or has a undulating structure having a wave shape. The absorbent article according to claim 10, wherein in the front sheet, the inside of the convex portion is formed by filling the constituent fibers of the front sheet, and the solid structure having no void inside is formed in the convex portion and the concave portion. Medium, the amount of constituent fibers is different, and the convex portion The amount of constituent fibers is larger than the amount of constituent fibers of the concave portion. The absorbent article of claim 10, wherein the front sheet is formed in the concave portion to form a plurality of openings, and the openings are regularly formed along the longitudinal direction (Y direction) in which the concave portion extends, at regular intervals, as the The shape of the opening is a shape of a circle, an ellipse, an oblong shape, a polygonal shape, or a combination of the shapes when the front sheet is viewed from the top, and the size of the opening is in a plan view. The projected area is 0.5 mm ² to 5 mm ² . The absorbent article of claim 10, wherein the base sheet has a basis weight of a narrow convex portion region and a base portion of a central portion of the underarm region having a convex portion having the largest width, and the front sheet is The overall basis weight is even. The absorbent article of claim 10, wherein the entire front sheet has a basis weight of 15 g/m ² or more and 150 g/m ² or less. The absorbent article according to claim 10, wherein the back sheet is made of a resin film or a laminate of a resin film and a non-woven fabric, and the sheet for forming a three-dimensional pleat is a laminated sheet of a stretchable film, a nonwoven fabric, a woven fabric or the like. The absorbent article according to claim 10, wherein the absorbent core constituting the absorbent body is formed by using agglomerates of fibers such as pulp fibers to hold particles of a water-absorbent polymer, and is used as a covering material constituting the absorbent body. As the hydrophilic sheet, either a packaged core material containing a water permeable tissue paper or a packaged core material containing a water permeable non-woven fabric is used.