JP7616951B2 - Pants-type disposable diapers - Google Patents

Description

The present invention relates to pants-type disposable diapers.

Conventionally, pants-type disposable diapers are known that have a ventral outer body, a rear outer body, and an absorbent body fixed between the ventral outer body and the rear outer body (see Patent Documents 1 to 3). In this type of pants-type disposable diaper, both sides of the ventral outer body and both sides of the rear outer body are joined to form a waist opening and a pair of leg openings.

In the pants-type disposable diaper of Patent Document 1, the ventral and dorsal exterior bodies include an outer layer sheet that forms the outer surface of the diaper, and an inner layer sheet that is disposed on the skin-facing side of the outer layer sheet. At the ends of the ventral and dorsal exterior bodies on the leg opening side, the ends of the outer and inner layers are aligned in the longitudinal direction of the diaper.

In the pants-type disposable diaper of Patent Document 2, the ventral and dorsal exterior bodies also include an outer layer sheet that forms the outer surface of the diaper, and an inner layer sheet arranged on the skin-facing side of the outer layer sheet. Patent Document 2 describes that the outer layer sheet is folded back to the skin-facing side at the ends of the leg opening side of the ventral and dorsal exterior bodies to cover the ends of the inner layer sheet.

In the pants-type disposable diaper of Patent Document 3, the ventral exterior body includes an outer layer sheet that forms the outer surface of the diaper and an inner layer sheet arranged on the skin-facing side of the outer layer sheet, and the rear exterior body is made of a single outer layer sheet. The rear exterior body has a two-layer structure in which the outer layer sheet is folded back at the opening edge of the waist opening. The end of the rear exterior body on the leg opening side is folded back multiple times.

JP 2019-514462 A JP 2017-185256 A JP 2016-202942 A

In a pants-type disposable diaper, the configuration of the end portion of the ventral outer body or the rear outer body on the leg opening side is important for the ease with which a wearer can move their legs when wearing the diaper. However, the pants-type disposable diapers of Patent Documents 1 to 3 have not been considered from the perspective of facilitating the wearer's movement of their legs when wearing the diaper, and there is room for improvement.
Therefore, an object of the present invention is to provide an absorbent article that can overcome the above-mentioned drawbacks of the conventional techniques.

The present invention provides a pants-type disposable diaper having a longitudinal direction corresponding to the front-to-rear direction of a wearer and a width direction perpendicular to the longitudinal direction, comprising a ventral region and a dorsal region, and a crotch region located between the ventral region and the dorsal region, and having an absorbent main body and an outer body arranged on the non-skin-facing side of the absorbent main body.
The exterior body includes a ventral exterior body disposed in the ventral region and a dorsal exterior body disposed in the dorsal region.
The ventral exterior body or the rear exterior body has an outer layer sheet that forms the outer surface of the pants-type disposable diaper, and an inner layer sheet arranged on the skin-facing side of the outer layer sheet. The expression "ventral exterior body or rear exterior body" includes both the ventral exterior body and the rear exterior body, and the both of the ventral exterior body and the rear exterior body.
The ventral outer body or the dorsal outer body has an overlapping region in which the outer layer sheet and the inner layer sheet overlap in the thickness direction, and a non-overlapping region in which one of the outer layer sheet and the inner layer sheet extends toward the crotch region from the edge of the other sheet on the crotch region side, and the overlapping region and the non-overlapping region have different rigidities.
The outer layer sheet or the inner layer sheet has a colored region, and the color difference between the overlapping region and the non-overlapping region is 1.5 or more.

The present invention provides a pants-type disposable diaper that allows the wearer to easily move their legs when wearing it.

FIG. 1 is a perspective view showing a typical embodiment of a pants-type disposable diaper according to the present invention. FIG. 2 is a developed plan view showing the non-skin facing surface side of the pants-type disposable diaper shown in FIG. 1 in an unfolded state. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a partially enlarged view showing a preferred configuration of the ventral exterior body or the dorsal exterior body. FIG. 5 is a developed plan view showing another embodiment of a pants-type disposable diaper according to the present invention, which is equivalent to FIG. FIG. 6 is a view of the pants-type disposable diaper shown in FIG. 5, which corresponds to FIG.

The present invention will now be described based on its preferred embodiments.
Fig. 1 shows a pants-type disposable diaper (hereinafter referred to as "diaper") 1, which is one embodiment of the absorbent article of the present invention. As shown in Figs. 1 to 3, the diaper 1 comprises a ventral region A that is arranged on the ventral side of a wearer when worn, a dorsal region B that is arranged on the dorsal side of the wearer, and a crotch region C located therebetween. The diaper 1 also has a longitudinal direction X corresponding to the front-to-rear direction of the wearer, and a width direction Y that corresponds to the longitudinal direction X. The longitudinal direction X is the direction from the ventral region A through the crotch region C to the dorsal region B. The crotch region C is arranged between the wearer's crotch when worn.

As shown in Figs. 1 to 3, the diaper 1 comprises an absorbent body 2 and an exterior body 3 arranged on the non-skin-facing side of the absorbent body 2. The exterior body 3 includes a ventral exterior body 3A arranged in the ventral region A and a rear exterior body 3B arranged in the rear region B. The diaper 1 has both side portions 3e, 3e along the longitudinal direction X of the ventral exterior body 3A and both side portions 3f, 3f along the longitudinal direction X of the rear exterior body 3B joined together to form a pair of side seal portions S, S, a waist opening WH, and a pair of leg openings LH, LH.

As shown in FIG. 2, the absorbent body 2 has an absorbent body 23, a top sheet 21 arranged on the skin-facing side of the absorbent body 23, and a back sheet 22 arranged on the non-skin-facing side of the absorbent body 23.
The absorbent body 23 , like the absorbent main body 2 , has an elongated shape in the longitudinal direction X of the diaper 1 , and is disposed between the topsheet 21 and the backsheet 22 .

The "skin-facing surface" refers to the surface of the diaper 1 or its constituent members that faces the wearer's skin when the diaper 1 is worn, and the "non-skin-facing surface" refers to the surface of the diaper 1 or its constituent members that faces away from the wearer's skin when the diaper 1 is worn. Furthermore, "when worn" and "worn state" refer to the state in which the diaper 1 is worn while maintaining the proper wearing position.

As described above, the exterior body 3 includes a ventral exterior body 3A and a rear exterior body 3B. In the present invention, the ventral exterior body 3A or the rear exterior body 3B has an outer layer sheet 32 that forms the outer surface of the diaper 1, and an inner layer sheet 31 arranged on the skin-facing side of the outer layer sheet 32. Either one or both of the ventral exterior body 3A and the rear exterior body 3B may have the outer layer sheet 32 and the inner layer sheet 31. In the embodiment shown in Figures 1 to 3, both the ventral exterior body 3A and the rear exterior body 3B have the outer layer sheet 32 and the inner layer sheet 31. In the diaper 1 of this embodiment, the exterior body 3 is divided into a ventral exterior body 3A and a rear exterior body 3B.

In this embodiment, the ventral exterior body 3A and the dorsal exterior body 3B have the same configuration. Therefore, the following description will mainly focus on the ventral exterior body 3A as an example, but the same description also applies to the dorsal exterior body 3B.

In the ventral exterior body 3A, a plurality of elastic members 33 are arranged between the outer layer sheet 32 and the inner layer sheet 31 in a stretched state along the width direction Y. In the area where the elastic members 33 overlap the absorbent body 2, they may be arranged so as not to exhibit elastic stretchability by being divided into small pieces or the like. In the diaper 1, the outer layer sheet 32 and the inner layer sheet 31 are joined together by adhesive, heat sealing, or the like over the entire area or at specified locations.

The ventral exterior body 3A has an overlapping region 45 where the outer layer sheet 32 and the inner layer sheet 31 overlap in the thickness direction Z. The ventral exterior body 3A also has a non-overlapping region 46 where the outer layer sheet 32 and the inner layer sheet 31 do not overlap in the thickness direction Z. The non-overlapping region 46 is located on the crotch region C side of the overlapping region 45. In the non-overlapping region 46, one of the outer layer sheet 32 and the inner layer sheet 31 extends from the edge of the crotch region C side of the other sheet to the crotch region C side. The non-overlapping region 46 is located at the end of the crotch region C side of the ventral exterior body 3A and extends along the width direction Y. In the embodiment shown in Figures 1 to 3, the inner layer sheet 31 extends from the edge 32c of the crotch region C side of the outer layer sheet 32 to the crotch region C side, and the extending portion forms the non-overlapping region 46. In this embodiment, the inner layer sheet 31 is longer in the longitudinal direction X than the outer layer sheet 32.

In the diaper 1 of this embodiment, the ventral exterior body 3A has the overlapping region 45 and the non-overlapping region 46, so that the wearer of the diaper 1 can easily move his/her legs. This point will be described in detail below. As described above, the overlapping region 45 and the non-overlapping region 46 have different rigidities because the number of sheets constituting each region 45, 46 is different. More specifically, the rigidity of the non-overlapping region 46 is smaller than the rigidity of the overlapping region 45. As described above, since there is a rigidity difference between the overlapping region 45 and the non-overlapping region 46, when the wearer moves his/her legs and the legs hit the end of the crotch region C side of the ventral exterior body 3A, the non-overlapping region 46 is likely to be displaced such that it rolls up from the boundary between the overlapping region 45 and the non-overlapping region 46 toward the non-skin facing surface side. Therefore, the end of the crotch region C side of the ventral exterior body 3A is unlikely to hinder the movement of the wearer's legs. Therefore, according to the diaper 1 of this embodiment, the wearer can easily move his/her legs. The non-overlapping region 46 is preferably formed at least between the side edge of the absorbent body 5 and the side seal portion S, and is preferably formed continuously between a pair of side seal portions S, S, as shown in Figure 1.
In this specification, the term "rigidity" refers to bending resistance measured by the handle-o-meter method specified in JIS L 1913. When it is difficult to measure in the state of the absorbent article, for example because the width of the non-overlapping portion is too short, the sheets constituting the outer casing may be separated, the sheet constituting the non-overlapping portion may be removed, and the sheet may be placed on the support table of a testing machine to perform the measurement.

The ratio (N2/N1) of the stiffness N2 of the non-overlapping region 46 to the stiffness N1 of the overlapping region 45 is preferably 0.28 or more, more preferably 0.49 or more, from the viewpoint of ease of movement of the wearer's feet, and is preferably 0.98 or less, more preferably 0.56 or less, and from the viewpoint of achieving both, is preferably 0.28 or more and 0.98 or less, more preferably 0.49 or more and 0.56 or less.

The stiffness N1 of the overlap region 45 is preferably 43 mN or more, more preferably 50 mN or more, and is preferably 75 mN or less, more preferably 68 mN or less, and is preferably 43 mN or more and 75 mN or less, more preferably 50 mN or more and 68 mN or less.
The stiffness N2 of the non-overlapping region 46 is preferably 21 mN or more, more preferably 30 mN or more, and is preferably 42 mN or less, more preferably 38 mN or less, and is preferably 21 mN or more and 42 mN or less, more preferably 30 mN or more and 38 mN or less.

The ratio (W1-W2/Ws) of the difference W1-W2 between the length W1 of the overlapping region 45 of the ventral region A in the longitudinal direction X and the length W2 of the non-overlapping region 46 of the ventral region A in the longitudinal direction X to the length Ws of the ventral exterior body 3A in the longitudinal direction X is preferably 1.2% or more, more preferably 1.4% or more, and more preferably 11% or less, more preferably 9% or less, and more preferably 1.2% or more and 11% or less, and more preferably 1.4% or more and 9% or less (see FIG. 2). The length Ws is equal to the sum of the length W1 of the overlapping region 45 of the ventral region A in the longitudinal direction X and the length W2 of the non-overlapping region 46 of the ventral region A in the longitudinal direction X.

The ratio (W3-W4/Ws) of the difference W3-W4 between the length W3 of the overlapping region 45 of the dorsal region B in the longitudinal direction X and the length W4 of the non-overlapping region 46 of the dorsal region B in the longitudinal direction X to the length Wt of the dorsal exterior body 3B in the longitudinal direction X is preferably 1.2% or more, more preferably 1.4% or more, and is preferably 10.5% or less, more preferably 8.5% or less, and is preferably 1.2% or more and 10.5% or less, and more preferably 1.4% or more and 8.5% or less (see FIG. 2). The length Wt is equal to the sum of the length W3 of the overlapping region 45 of the dorsal region B in the longitudinal direction X and the length W4 of the non-overlapping region 46 of the dorsal region B in the longitudinal direction X.

The difference in length W1-W2 between the overlapping region 45 and the non-overlapping region 46 in the ventral region A is preferably 1 mm or more, more preferably 2 mm or more, and is preferably 8 mm or less, more preferably 6 mm or less, and is preferably 1 mm or more and 8 mm or less, more preferably 2 mm or more and 6 mm or less.
The difference in length W3-W4 between the overlapping region 45 and the non-overlapping region 46 in the back region B is preferably 3 mm or more, more preferably 5 mm or more, and is preferably 10 mm or less, more preferably 8 mm or less, and is preferably 3 mm or more and 10 mm or less, more preferably 5 mm or more and 8 mm or less.

The distance Ws from the outer edge in the longitudinal direction X of the ventral outer body 3A to the edge of the crotch region C of the overlap region 45 of the ventral region A is preferably 79 mm or more, more preferably 89 mm or more, and also preferably 148 mm or less, more preferably 138 mm or less, and also preferably 79 mm or more and 148 mm or less, more preferably 89 mm or more and 138 mm or less.
The distance Wt from the outer edge in the longitudinal direction X of the rear exterior body 3B to the edge of the crotch region C of the overlap region 45 of the rear region B is preferably 110 mm or more, more preferably 120 mm or more, and preferably 207 mm or less, more preferably 197 mm or less, and preferably 110 mm or more and 207 mm or less, more preferably 120 mm or more and 197 mm or less.

The ratio W1/Ws of the length W1 of the overlap region 45 of the ventral region A in the longitudinal direction X to the length Ws of the ventral outer body 3A in the longitudinal direction X is preferably 75 mm or more, more preferably 80 mm or more, and preferably 145 mm or less, more preferably 140 mm or less, and preferably 75 mm or more and 145 mm or less, more preferably 80 mm or more and 140 mm or less.
The length W2 of the non-overlapping region 46 of the ventral region A in the longitudinal direction X is preferably 0 mm or more, more preferably 2 mm or more, and preferably 12 mm or less, more preferably 10 mm or less, and preferably 0 mm or more and 12 mm or less, more preferably 2 mm or more and 10 mm or less.

The ratio W3/Wt of the length W3 of the overlap region 45 of the rear region B in the longitudinal direction X to the length Wt of the rear exterior body 3B in the longitudinal direction X is preferably 105 mm or more, more preferably 110 mm or more, and preferably 200 mm or less, more preferably 195 mm or less, and preferably 105 mm or more and 200 mm or less, more preferably 110 mm or more and 195 mm or less.
The length W4 of the non-overlapping region 46 of the back region B in the longitudinal direction X is preferably 0 mm or more, more preferably 2 mm or more, and preferably 12 mm or less, more preferably 10 mm or less, and preferably 0 mm or more and 12 mm or less, more preferably 2 mm or more and 10 mm or less.

In the present invention, the outer layer sheet 32 or the inner layer sheet 31 has a colored colored region 35. Either the outer layer sheet 32 or the inner layer sheet 31 may have the colored region 35. The colored region 35 may be arranged in a part of the outer layer sheet 32 or the inner layer sheet 31, or may be arranged over the entire area of the outer layer sheet 32 or the inner layer sheet 31. When the colored region 35 is arranged in a part of the outer layer sheet 32 or the inner layer sheet 31, it is usually necessary to have the colored region 35 across the boundary between the overlap region 45 and the non-overlapping region 46.

In this embodiment, the colored region 35 is arranged over the entire area of the inner layer sheet 31. The outer layer sheet 32 has light transmittance, so that the color of the colored region 35 of the inner layer sheet 31 can be seen even when the overlapping region 45 of the outer layer sheet 32 and the inner layer sheet 31 is viewed from the outer layer sheet 32 side. Therefore, the color of the colored region 35 of the inner layer sheet 31 is visible through the overlapping region 45, and the color of the colored region 35 is directly visible in the non-overlapping region 46. With this configuration, in the diaper 1 of this embodiment, the overlapping region 45 and the non-overlapping region 46 have different colors when viewed from the outside. This makes it easier to visually distinguish the non-overlapping region 46, which has low rigidity and is prone to rolling up, from the overlapping region 45. Therefore, parents, caregivers, etc. can easily determine whether the wearer of the diaper 1 of this embodiment can easily move their legs.

When the outer sheet 32 has the colored region 35 instead of the inner sheet 31, the color of the outer sheet 32 is directly visible in the overlapping region 45, and the color of the inner sheet 31 is directly visible in the non-overlapping region 46. This makes it easier to recognize the non-overlapping region 46 by the difference in color when the diaper is viewed from the outside, since the non-overlapping region 46 and the overlapping region 45 have different colors.
When one of the inner sheet 31 and the outer sheet 32 has a colored region 35, the other sheet is preferably white, which is the color of a typical nonwoven fabric, from the viewpoint of increasing the color difference, but may be colored other than white as long as a predetermined color difference is generated between the non-overlapping region 46 and the overlapping region 45. For example, one sheet may be a dark color such as green, red, or blue, while the other sheet may be a light color such as light green, light red, or light blue. The color of one sheet and the color of the other sheet may be the same color family or different colors.

In either case where either one of the inner sheet 31 and the outer sheet 32 has a colored region, or where both sheets 31, 32 have colored regions, from the viewpoint of making it easy to visually distinguish between the non-overlapping region 46 and the overlapping region 45 and effectively recognizing that the presence of the non-overlapping region 46 makes it easier to move the legs, the color difference between the overlapping region 45 and the non-overlapping region 46 is preferably 1.5 or more, more preferably 1.7 or more, and even more preferably 2.0 or more. There is no particular upper limit, but from the viewpoint of a sense of uniformity in the color of the diaper, for example, the color difference between the overlapping region 45 and the non-overlapping region 46 is preferably 15 or less, and more preferably 10 or less.
As in the embodiment shown in Figures 5 and 6, even when the outer layer sheet 32 extends from the edge 31c on the crotch region C side of the inner layer sheet 31 toward the crotch region C, and this extending portion forms a non-overlapping region 46, it is preferable that the color difference between the overlapping region 45 and the non-overlapping region 46 be within the above-mentioned range, from the viewpoint of making the non-overlapping region 46 and the overlapping region 45 look different to ensure that the ease of leg movement due to the presence of the non-overlapping region 46 is visually recognized, and from the viewpoint of color uniformity, etc.

When the diaper 1 is viewed from the non-skin-facing side, in order to make it easy to visually distinguish the non-overlapping region 46 from the back sheet 22 and to effectively recognize that the presence of the non-overlapping region 46 makes it easier to move the legs, the color difference between the non-overlapping region 46 and the back sheet 22 is preferably 8 or more, more preferably 10 or more, and even more preferably 20 or more. There is no particular upper limit, but from the perspective of, for example, a sense of uniformity in the color of the diaper, the color difference between the non-overlapping region 46 and the back sheet 22 is preferably 15 or less, and more preferably 13 or less.

In this specification, color difference refers to "color difference in the L*a*b* color system" and can be measured by the following method. The greater the color difference, the more easily the difference in color can be recognized.

[Method of measuring color difference (ΔE ^* value)]
As a color difference meter, a colorimeter/densitometer eXact (product name) manufactured by X-Rite Corporation can be used. In the "L*a*b* color system" defined in JIS Z 8729, L* indicates brightness, a* and b* indicate color directions, with a* indicating approximately the red direction, -a* indicating approximately the green direction, b* indicating approximately the yellow direction, and -b* indicating approximately the blue direction. The color difference (ΔE*) is a value calculated by the following formula (1).
ΔE*=[(ΔL*) ² + (Δa*) ² + (Δb*) ² ] ^1/2 ...(1)
ΔL*, Δa*, and Δb* are the differences in the L*, a*, and b* values between the two contrasting colors, respectively. For example, ΔL* is calculated by ΔL*=L*2-L*1.
The measurement is performed by placing the part of the ventral or dorsal exterior body of the absorbent article that is not overlapping with the absorbent main body on a horizontal support table without wrinkles or bends, with the non-skin-facing side facing vertically upward.
Then, the tip of the sensor is pressed against each of the overlapping region 45 and the non-overlapping region 46 in the portion placed on the support table to perform the measurement. The measurement is performed by pressing the measuring device perpendicularly against the diaper placed on the table. This measurement is performed at any three points for each of the overlapping region 45 and the non-overlapping region 46, and the average value is taken as the respective measured value.
When the sample has high light transmittance and is affected by the color of the support stand, a white copy paper is fixed on the support stand, and the sample is placed on the copy paper for measurement.
If it is difficult to measure in the absorbent article state because the width of the non-overlapping portion is too short, for example, each sheet that makes up the outer body can be separated, the sheet that makes up the non-overlapping portion can be removed, and the sheet can be placed on the support table to perform the measurement.
Alternatively, a sample may be cut out from a portion of the ventral or dorsal exterior body that does not overlap the absorbent main body, and the sample may be placed on a horizontal support table without wrinkles or bends, with the non-skin-facing surface facing vertically upward, and measurements may be taken by pressing the tip of a sensor against each of the overlapping and non-overlapping regions 45 and 46 of the sample.

The colored regions in the outer layer sheet 32 or the inner layer sheet 31 may be uncolored (e.g., white) sheets (non-stretchable nonwoven fabrics) that have been colored by known dyeing methods such as printing, or the outer layer sheet 32 or the inner layer sheet 31 may contain dyed fibers as constituent fibers. Dyed fibers are fibers that are colored at the fiber manufacturing stage, and are manufactured, for example, through a coloring process in which a pigment or other coloring agent is added to a manufacturing intermediate product during the process from resin manufacturing to fiberization. When a colored region is colored with dyed fibers, it has better abrasion resistance and fastness and is less susceptible to color transfer than a colored region made by coloring an uncolored sheet, and is also superior in terms of flexibility, texture, etc.

When a colored region is provided in the inner layer sheet and is extended from the outer layer sheet to form a non-overlapping region, from the viewpoint of providing visual characteristics, it is preferable that the colored region of the inner layer ^sheet has an ^{L *} value of 56 to 96, an a ^* value of -70 to -40, and a b ^* value of -20 to 30 in the L*a* ^b * color system.

On the other hand, when a colored region is provided in the inner layer sheet and the outer layer sheet is made to extend beyond the colored region to form a non-overlapping region, from the viewpoint of providing visual characteristics, it is preferable that the colored region of the inner layer sheet has an L ^* value of 56 to 96, an a ^* value of -70 to -40, and a b ^* value of -20 to 30.

From the viewpoint of making it easy to visually distinguish the non-overlapping region 46 from the back sheet 22, it is preferable that the back sheet 22 has an L ^* value of 56 to 96, an a ^* value of -70 to -40, and a b ^* value of -20 to 30. The back sheet 22 may have a design on the skin-facing or non-skin-facing surface, and when the back sheet 22 has a design, the L ^* value, a ^* value, and b ^* value are determined by measuring the value of the background color of the back sheet 22 excluding the design. Here, the design means a pattern such as a picture, symbol, or letter.

2 and 3, the ventral exterior body 3A has an area (hereinafter also referred to as a "stacking area") 41 that overlaps with the absorbent main body 2. In the stacking area 41, a center part of the ventral exterior body 3A in the width direction Y and an end part of the absorbent main body 2 in the longitudinal direction X overlap with each other.
The ventral outer body 3A has areas (hereinafter also referred to as "non-laminated areas") 42 that do not overlap with the absorbent main body 2 on both sides of the laminated area 41 in the width direction Y and on the waist opening WH side of the edge of the absorbent main body 2 in the ventral outer body 3A.

The laminated region 41 has a joint region 43 where the ventral exterior body 3A and the absorbent main body 2 are joined, and a non-joint region 44 where the exterior body 3 and the absorbent main body 2 are not joined. The non-joint region 44 is located on the crotch region C side of the joint region 43. In this embodiment, the non-joint region 44 extends in the width direction Y. In other words, the end portion of the ventral exterior body 3A on the crotch region C side is not joined to the absorbent main body 2, and the end portion of the ventral exterior body 3A is located in the non-joint region 44.
The non-bonded region 44 preferably includes the non-overlapping region 46 of the ventral-side outer body 3A. By including the non-overlapping region 46 in the non-bonded region 44, the non-overlapping region 46 becomes more likely to be rolled up when a wearer of the diaper 1 moves his/her legs, making it easier for the wearer to move his/her legs.

It is more preferable that the non-bonded region 44 includes not only the non-overlapping region 46 but also the overlapping region 45. The portion of the overlapping region 45 included in the non-bonded region 44 is usually a part of the overlapping region 45 on the crotch region C side, and is a part of the overlapping region 45 adjacent to the non-overlapping region 46. Since the non-bonded region 44 includes a part of the overlapping region 45, when the wearer moves his/her legs, not only the non-overlapping region 46 but also the part of the overlapping region 45 that is not bonded to the absorbent main body 2 is likely to be rolled up, making it easier for the wearer to move his/her legs.
It is preferable that the non-bonded region 44 includes a non-overlapping region 46 throughout the entire width direction Y of the portion overlapping with the absorbent main body 2, and it is preferable that the non-overlapping region 46 and the overlapping region 45 are included throughout the entire width direction Y of the portion overlapping with the absorbent main body 2.

In the diaper 1, as shown in FIG. 4, it is preferable that the outer layer sheet 32 and the inner layer sheet 31 are intermittently joined, and it is more preferable that the outer layer sheet 32 and the inner layer sheet 31 are intermittently joined in the width direction Y. This can improve the fit of the diaper 1 around the legs. In the embodiment shown in FIG. 4, the outer layer sheet 32 and the inner layer sheet 31 are joined by a plurality of joints 36. In the embodiment shown in FIG. 4, a joint row 36R in which a plurality of joints 36 are arranged in the width direction Y is arranged at intervals in the longitudinal direction X. In the joint rows 36R adjacent to each other in the longitudinal direction X, the positions of the individual joints 36 constituting the joint row 36R in the width direction Y are consistent. In either one or both of the ventral exterior body 3A and the dorsal exterior body 3B, the outer layer sheet 32 and the inner layer sheet 31 may be intermittently joined. From the viewpoint of improving the fit of the diaper 1 around the legs, it is preferable that the outer layer sheet 32 and the inner layer sheet 31 are intermittently joined in the dorsal exterior body 3B, and it is more preferable that the outer layer sheet 32 and the inner layer sheet 31 are intermittently joined in both the ventral exterior body 3A and the dorsal exterior body 3B.

In the embodiment shown in FIG. 4, the elastic member 33 disposed between the outer layer sheet 32 and the inner layer sheet 31 is disposed so as not to pass through the joint 36. Specifically, the elastic member 33 is disposed so as to pass between the joints 36 adjacent to each other in the longitudinal direction X.

In the diaper 1, it is preferable that the non-overlapping region 46 of both sides 3e, 3e of the ventral exterior body 3A is folded back to the non-skin-facing side at the side seal portion S. More specifically, it is preferable that the side portion 3e of the ventral exterior body 3A and the side portion 3f of the back exterior body 3B are joined in a state in which the end of the crotch side 3C of the inner layer sheet 31 is folded back to the non-skin-facing side at the side portion 3e of the ventral exterior body 3A. In other words, it is preferable that the part of the ventral exterior body 3A that is folded back to the non-skin-facing side is joined to the part of the ventral exterior body 3A that is not folded back to the non-skin-facing side. By doing so, when the diaper 1 is worn, the non-overlapping region 46 is turned up in the vicinity of the side seal portion S, making it easier for the wearer to move his/her legs. The non-overlapping region 46 may be folded back to the non-skin facing surface only at the side 3e of the ventral exterior body 3A, and may not be folded back to the non-skin facing surface between both sides 3e of the ventral exterior body 3A. Alternatively, the non-overlapping region 46 may be folded back to the non-skin facing surface between both sides 3e of the ventral exterior body 3A. The same is true for the back exterior body 3B, and it is preferable that the non-overlapping region 46 is folded back to the non-skin facing surface at both sides 3f, 3f of the back exterior body 3B in the side seal portion S. More specifically, it is preferable that the part of the back exterior body 3B that is folded back to the non-skin facing surface is joined to the part of the back exterior body 3B that is not folded back to the non-skin facing surface.

When the position of the edge of the ventral exterior body 3A on the outer side in the longitudinal direction X of the ventral exterior body 3A and the position of the edge of the edge of the back exterior body 3B on the outer side in the longitudinal direction X are aligned, the position of the end on the crotch region C side of the ventral exterior body 3A and the back exterior body 3B may be aligned or may be different. Here, the edge on the outer side in the longitudinal direction X of the ventral exterior body 3A or the back exterior body 3B means the edge on the waist opening WH side of the ventral exterior body 3A or the back exterior body 3B in the longitudinal direction X. When the positions of the ends on the crotch region C side of the ventral exterior body 3A and the back exterior body 3B are different, it is preferable that the end on the crotch region C side of the back exterior body 3B is located closer to the crotch region C side than the ventral exterior body 3A. This makes it possible to assist in opening and closing the legs forward. When the position of the outer edge in the longitudinal direction X of the ventral exterior body 3A is aligned with the position of the outer edge in the longitudinal direction X of the dorsal exterior body 3B, in order to position the end of the dorsal exterior body 3B closer to the crotch region C than the ventral exterior body 3A, for example, the length of the dorsal exterior body 3B in the longitudinal direction X (W3+W4) can be made longer than the length of the ventral exterior body 3A in the longitudinal direction X (W1+W2) (see FIG. 2).

Figures 5 and 6 show another embodiment of the present invention. In the diaper 1' of the embodiment shown in Figures 5 and 6, the outer layer sheet 32 extends from the edge 31c of the inner layer sheet 31 on the crotch region C side toward the crotch region C, and this extending portion forms a non-overlapping region 46. In this embodiment, the outer layer sheet 32 is longer in the longitudinal direction X than the inner layer sheet 31. In the diaper 1' of this embodiment, the presence of the non-overlapping region 46 allows the wearer to move his/her legs easily, as in the diaper 1 of the embodiment shown in Figures 1 to 3.

5 and 6, the colored region 35 is disposed over the entire area of the inner layer sheet 31, and the outer layer sheet 32 is light-transmitting. In the overlapping region 45 where the outer layer sheet 32 and the inner layer sheet 31 overlap, the color of the colored region 35 of the inner layer sheet 31 is visible through the inner layer sheet 31, and in the non-overlapping region 46, the color of the outer layer sheet 32 is directly visible. With this configuration, the overlapping region 45 and the non-overlapping region 46 of the diaper 1' also have different colors when viewed from the outside. Therefore, in the diaper 1' of this embodiment, as in the diaper 1 of the embodiment shown in Figs. 1 to 4, a guardian, a caregiver, or the like can easily determine whether or not a wearer of the diaper 1' of this embodiment can easily move his/her legs.
5 and 6, even when the outer sheet 32 is extended from the edge 31c of the inner sheet 31 on the crotch region C side to form the non-overlapping region 46, the outer sheet 32 may have the colored region 35 instead of the inner sheet 31, or the inner sheet 31 and the outer sheet 32 may have the colored region 35. For example, one sheet may be a dark color such as green, red, or blue, while the other sheet may be a light color such as light green, light red, or light blue. The color of one sheet and the color of the other sheet may be the same color family or different colors.

Next, matters common to the above-mentioned embodiments will be described.
The top sheet 21 may be a liquid-permeable sheet, such as a nonwoven fabric or a perforated film. The surface of the top sheet facing the skin may be uneven. For example, a plurality of scattered convex portions may be formed on the surface of the top sheet facing the skin. Alternatively, ridges and grooves extending in one direction may be alternately formed on the surface of the top sheet facing the skin. For such a purpose, the top sheet 21 may be formed using two or more sheets of nonwoven fabric.

On the other hand, the back sheet 22 may be, for example, a liquid-impermeable film or a spunbond, meltblown, or spunbond laminated nonwoven fabric. A liquid-impermeable film may be provided with a plurality of micropores to impart water vapor permeability to the film. In order to further improve the feel of the absorbent article against the skin, a sheet with a good texture, such as a nonwoven fabric, may be laminated on the outer surface of the back sheet.

The absorbent body 23 has an absorbent core. The absorbent core is composed of, for example, a stack of hydrophilic fibers such as cellulose including pulp, a mixed stack of the hydrophilic fibers and an absorbent polymer, a stack of absorbent polymer, a laminated structure in which an absorbent polymer is supported between two absorbent sheets, or the like. At least the skin-facing surface of the absorbent core may be covered with a liquid-permeable core wrap sheet, or the entire surface including the skin-facing surface and the non-skin-facing surface may be covered with the core wrap sheet. As the core wrap sheet, for example, tissue paper made of hydrophilic fibers or liquid-permeable nonwoven fabric can be used.

In addition to the above-mentioned top sheet 21, back sheet 22 and absorbent body 23, the absorbent body 2 may be provided with leak-proof cuffs extending along the longitudinal direction on both sides of the skin-facing side in accordance with the specific use of the pants-type disposable diaper. The leak-proof cuffs generally have a base end and a free end. The leak-proof cuffs have a base end on the skin-facing side of the disposable diaper and stand up from the skin-facing side. The leak-proof cuffs are made of a liquid-resistant or water-repellent material and are breathable. An elastic member made of rubber thread or the like may be arranged in a stretched state at or near the free end of the leak-proof cuff. When the pants-type disposable diaper is worn, this elastic member contracts, causing the leak-proof cuffs to stand up toward the wearer's body, effectively preventing liquid excreted on the top sheet from leaking outward in the width direction of the pants-type disposable diaper along the top sheet.

The pant-type disposable diaper of the present invention has been described above based on one preferred embodiment, but the laminated nonwoven fabric of the present invention is not limited to the above-mentioned embodiment. For example, the pant-type disposable diaper of the present invention is not limited to one in which the ventral outer body 3A and the rear outer body 3B have the same configuration. Only one of the ventral outer body 3A and the rear outer body 3B may have the above-mentioned configuration.

In the above-described embodiment, the inner layer sheet 31 has the colored region 35, but in the pants-type disposable diaper of the present invention, the outer layer sheet 32 may have the colored region 35, or both the outer layer sheet 32 and the inner layer sheet 31 may have the colored region 35. From the viewpoint of making it easier to visually distinguish between the overlapping region 45 and the non-overlapping region 46, it is preferable that only one of the outer layer sheet 32 and the inner layer sheet 31 has the colored region 35.

There is no particular limitation on the color of the colored region 35 of the inner sheet 31 or the outer sheet 32. The colored region 35 may be divided into a plurality of regions. In this case, the plurality of regions may have different colors, shapes, etc. or may be the same.
The colored area 35 may be a character, a figure, a symbol, etc. The colored area 35 may be a single color without a pattern.

In addition, when the joints 36 between the outer sheet 32 and the inner sheet 31 form the joint row 36R, the joints 36 constituting the joint row 36R may be offset from one another in the width direction Y. For example, the joints 36 may be arranged in a staggered pattern.
The joint 36 may be continuous in the longitudinal direction X.
The method for forming the joint 36 is not particularly limited, and for example, the joint 36 may be formed by applying an adhesive or the like to the outer layer sheet 32 or the inner layer sheet 31, or the joint 36 may be formed by fusing the outer layer sheet 32 and the inner layer sheet 31 to each other using heat, ultrasound, or the like.

The joining region 43 may also include an overlapping region 45 and a non-overlapping region 46. In this case, in the region where the joining region 43 and the overlapping region 45 overlap, the ventral exterior body 3A or the back exterior body 3B and the absorbent body 2 are preferably joined with a hot melt adhesive. The ventral exterior body 3A or the back exterior body 3B and the absorbent body 2 may be joined with a hot melt adhesive in the entire region where the joining region 43 and the overlapping region 45 overlap, or may be joined with a hot melt adhesive in a part of the region where the joining region 43 and the overlapping region 45 overlap. In the region where the absorbent body 2 does not overlap in the overlapping region 45, the outer layer sheet 32 and the inner layer sheet 31 are preferably joined by thermal bonding. In the region where the stacking region 41 and the non-overlapping region 46 overlap, the ventral exterior body 3A or the back exterior body 3B and the absorbent body 2 are preferably joined by thermal bonding. The ventral exterior body 3A or the dorsal exterior body 3B and the absorbent body 2 may be joined by thermal bonding in the entire area where the stacked area 41 and the non-overlapping area 46 overlap, or may be joined by thermal bonding in a portion of the area where the stacked area 41 and the non-overlapping area 46 overlap.

In the area where the laminated region 41 and the overlapping region 45 overlap, the ventral exterior body 3A or the dorsal exterior body 3B and the absorbent body 2 are joined with hot melt adhesive, and in the area where the absorbent body 2 does not overlap in the overlapping region 45, the outer layer sheet 32 and the inner layer sheet 31 are joined by thermal bonding, and in the area where the laminated region 41 and the non-overlapping region 46 overlap, the ventral exterior body 3A or the dorsal exterior body 3B and the absorbent body 2 are joined by thermal bonding. The advantages of this are as follows: The contraction force of the overlapping region is not hindered by thermal bonding compared to when it is joined with hot melt adhesive, so it is easier to follow the movement of the body.

The present invention further discloses the following supplementary notes.
＜1＞
A pants-type disposable diaper having a longitudinal direction corresponding to the front-rear direction of a wearer and a width direction perpendicular to the longitudinal direction, comprising a ventral region and a dorsal region, and a crotch region located between the ventral region and the dorsal region, the diaper having an absorbent main body and an exterior body disposed on a non-skin-facing side of the absorbent main body,
The exterior body includes a ventral exterior body arranged in the ventral region and a dorsal exterior body arranged in the dorsal region,
The ventral side exterior body or the rear side exterior body has an outer layer sheet forming an outer surface of the pants-type disposable diaper, and an inner layer sheet arranged on the skin-facing side of the outer layer sheet,
The ventral exterior body or the dorsal exterior body has an overlapping region where the outer layer sheet and the inner layer sheet overlap in a thickness direction, and a non-overlapping region where one of the outer layer sheet and the inner layer sheet extends toward the crotch region from an edge of the other sheet on the crotch region side, and the overlapping region and the non-overlapping region have different rigidities,
The outer sheet or the inner sheet has a colored region, and the color difference between the overlapping region and the non-overlapping region is 1.5 or more.

＜2＞
the ventral exterior body or the rear exterior body has an area overlapping with the absorbent main body, the area having a joining area where the exterior body and the absorbent main body are joined, and a non-joint area located on the crotch area side of the joining area and where the exterior body and the absorbent main body are not joined,
The pants-type disposable diaper according to <1>, wherein the non-bonded region includes the non-overlapping region.
＜3＞
The pants-type disposable diaper according to <2>, wherein the non-bonded region includes the overlapping region in addition to the non-overlapping region.
＜4＞
The pants-type disposable diaper according to any one of <1> to <3>, wherein the outer layer sheet and the inner layer sheet of the ventral side outer body or the dorsal side outer body are intermittently joined in the width direction.

＜5＞
A pair of side seal portions are formed by joining both side portions of the ventral exterior body along the longitudinal direction and both side portions of the dorsal exterior body along the longitudinal direction,
The pants-type disposable diaper according to any one of <1> to <4>, wherein in the side seal portion, the non-overlapping regions of both sides of the ventral exterior body or the dorsal exterior body are folded back and joined to the non-skin-facing surface side.
＜6＞
The pants-type disposable diaper described in <5>, wherein in at least a portion of the pair of side seal portions, the folded-back portion of the rear exterior body is joined to a non-folded portion of the rear exterior body.
＜７＞
The absorbent body includes an absorbent body, a top sheet covering the skin-facing side of the absorbent body, and a back sheet covering the non-skin-facing side of the absorbent body,
The pants-type disposable diaper according to any one of <1> to <6>, wherein a color difference between the non-overlapping region and the back sheet is 15 or less.
＜8＞
The pants-type disposable diaper according to any one of <1> to <7>, wherein a ratio of a rigidity of the non-overlapping region to a rigidity of the overlapping region is 0.28 or more and 0.98 or less, preferably 0.49 or more and 0.56 or less.

＜9＞
The pants-type disposable diaper according to any one of <1> to <8>, wherein a ratio (W1-W2/Ws) of a difference W1-W2 between a length W1 of the overlapping region of the abdominal region in the longitudinal direction and a length W2 of the non-overlapping region of the abdominal region in the longitudinal direction, to a distance Ws from an outer edge of the abdominal outer body in the longitudinal direction to an edge of the overlapping region of the abdominal region on the crotch region side, is 1.2% or more and 11% or less, preferably 1.4% or more and 9% or less.
＜10＞
The pants-type disposable diaper according to any one of <1> to <9>, wherein a ratio (W3-W4/Ws) of a difference W3-W4 between a length W3 of the overlapping region of the back region in the longitudinal direction and a length W4 of the non-overlapping region of the back region in the longitudinal direction, to a distance Wt from an outer edge of the back exterior body in the longitudinal direction to an edge of the overlapping region of the back region on the crotch region side, is 1.2% or more and 10.5% or less, preferably 1.4% or more and 8.5% or less.
<11>
The pants-type disposable diaper according to any one of <1> to <10>, wherein the exterior body is divided into the ventral side exterior body and the rear side exterior body.
＜12＞
The pants-type disposable diaper according to any one of <1> to <11>, wherein in the rear-side exterior body, the outer sheet and the inner sheet are joined intermittently.

＜13＞
The pants-type disposable diaper according to any one of <1> to <12>, wherein the outer layer sheet has a length in the longitudinal direction longer than that of the inner layer sheet, and the outer layer sheet has the colored region.
＜14＞
The pants-type disposable diaper according to any one of <1> to <12>, wherein the outer layer sheet is longer in the longitudinal direction than the inner layer sheet, and the inner layer sheet has the colored region.
＜15＞
The pants-type disposable diaper according to any one of <1> to <12>, wherein the inner layer sheet has a length in the longitudinal direction longer than that of the outer layer sheet, and the outer layer sheet has the colored region.
＜16＞
The pants-type disposable diaper according to any one of <1> to <12>, wherein the inner layer sheet has a length in the longitudinal direction longer than that of the outer layer sheet, and the inner layer sheet has the colored region.
＜17＞
The pants-type disposable diaper according to any one of <1> to <12>, wherein the colored region is disposed over the entire area of the inner layer sheet, and the outer layer sheet has light transmittance.

＜18＞
An elastic member is disposed between the inner sheet and the outer sheet,
The outer layer sheet and the inner layer sheet are joined together at a plurality of joints arranged in the width direction and spaced apart in the longitudinal direction,
The pants-type disposable diaper according to any one of <1> to <17>, wherein the elastic members are disposed between the plurality of joint portions adjacent to each other in the longitudinal direction.
＜19＞
The pants-type disposable diaper according to any one of <1> to <18>, wherein the colored region has any one of a letter, a figure, and a symbol.
＜20＞
The underpants-type disposable diaper according to any one of <1> to <19>, wherein the colored region preferably has an L ^* value of 56 to 96, an a ^* value of −70 to −40, and a b ^* value of −20 to 30.
＜21＞
The pants-type disposable diaper according to any one of <1> to <20>, wherein the background color excluding the design of the back sheet preferably has an L ^* value of 56 to 96, an a ^* value of −70 to −40, and a b ^* value of −20 to 30.

＜22＞
When the position of the longitudinal outer edge of the ventral exterior body and the position of the longitudinal outer edge of the dorsal exterior body are aligned,
The pants-type disposable diaper according to any one of <1> to <21>, wherein an end portion of the rear exterior body on the crotch region side is located closer to the crotch region side than the ventral exterior body.
＜23＞
The absorbent body has a laminated region in which the ventral exterior body or the dorsal exterior body overlaps with the absorbent body,
In a region where the laminated region and the overlapping region overlap, the ventral exterior body or the dorsal exterior body and the absorbent main body are joined with a hot melt adhesive,
In the overlapping region, the outer sheet and the inner sheet are joined by thermal bonding in a region not overlapping the absorbent body,
The pants-type disposable diaper according to any one of <1> to <22>, wherein in an area where the laminated area and the non-overlapping area overlap, the ventral exterior body or the dorsal exterior body and the absorbent main body are joined by thermal bonding.

REFERENCE SIGNS LIST 1, 1' pants-type disposable diaper 2 absorbent body 21 top sheet 22 back sheet 23 absorbent body 3 exterior body 3A ventral exterior body 3B rear exterior body 31 inner layer sheet 32 outer layer sheet 35 colored region 33 elastic member 41 laminated region 42 non-laminated region 43 bonded region 44 non-bonded region 45 overlapping region 46 non-overlapping region A ventral region B rear region C crotch region X longitudinal direction Y width direction

Claims (6)

A pants-type disposable diaper having a longitudinal direction corresponding to the front-rear direction of a wearer and a width direction perpendicular to the longitudinal direction, comprising a ventral region and a dorsal region, and a crotch region located between the ventral region and the dorsal region, the diaper having an absorbent main body and an exterior body disposed on a non-skin-facing side of the absorbent main body,
The exterior body includes a ventral exterior body arranged in the ventral region and a dorsal exterior body arranged in the dorsal region,
The ventral side exterior body or the rear side exterior body has an outer layer sheet forming an outer surface of the pants-type disposable diaper, and an inner layer sheet arranged on the skin-facing side of the outer layer sheet,
The ventral exterior body or the dorsal exterior body has an overlapping region where the outer layer sheet and the inner layer sheet overlap in a thickness direction, and a non-overlapping region where one of the outer layer sheet and the inner layer sheet extends toward the crotch region from an edge of the other sheet on the crotch region side, and the overlapping region and the non-overlapping region have different rigidities,
the outer layer sheet or the inner layer sheet has a colored region, and a color difference between the overlapping region and the non-overlapping region is 1.5 or more;
A pair of side seal portions are formed by joining both side portions of the ventral exterior body along the longitudinal direction and both side portions of the dorsal exterior body along the longitudinal direction,
In the side seal portion, the non-overlapping regions of both side portions of the ventral exterior body or the dorsal exterior body are folded back and joined to the non-skin-facing surface side of the pants-type disposable diaper. the ventral exterior body or the rear exterior body has an area overlapping with the absorbent main body, the area having a joining area where the exterior body and the absorbent main body are joined, and a non-joint area located on the crotch area side of the joining area and where the exterior body and the absorbent main body are not joined,
The pant-type disposable diaper according to claim 1 , wherein the non-bonded regions include the non-overlapping regions. The pants-type disposable diaper according to claim 2, wherein the non-bonded region includes the overlapping region in addition to the non-overlapping region. The pants-type disposable diaper according to any one of claims 1 to 3, wherein the outer layer sheet and the inner layer sheet of the ventral outer body or the dorsal outer body are intermittently joined in the width direction. The absorbent body includes an absorbent body, a top sheet covering the skin-facing side of the absorbent body, and a back sheet covering the non-skin-facing side of the absorbent body,
5. The pants-type disposable diaper according to claim 1, wherein a color difference between the non-overlapping region and the back sheet is 15 or less. The pants-type disposable diaper according to any one of claims 1 to 5 , wherein a ratio of a stiffness of the non-overlapping region to a stiffness of the overlapping region is 0.28 or more and 0.98 or less.

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