JP7437229B2 - disposable diapers - Google Patents

Description

The present invention relates to disposable diapers.

Absorbent articles such as disposable diapers generally include an absorbent main body and an exterior body disposed on the side of the absorbent main body that does not face the skin. Both side edges of the exterior body and both side edges of the exterior body at the dorsal side portion corresponding to the rear body are joined to form a pair of seal portions, a waist opening, and a pair of leg openings. .

Patent Document 1 discloses a disposable diaper having such a configuration, which has longitudinal and lateral directions, and a vertical center line that divides the lateral dimension into two, and has a front and rear waist area, and a front and rear waist area. A disposable diaper is disclosed that includes a crotch area located therebetween, a diaper main body having an absorbent body, a pair of waist belts for connecting the front and rear waist areas, a waist opening, and a pair of leg openings. This diaper has a pair of waist belts that are aligned vertically from the leg opening side to the waist opening side in the front and back waist areas, so that the diaper can easily expand the waist opening and be stably held on the body. It is also disclosed that it is joined to the diaper body via an approximating joining line.

Further, Patent Document 2 discloses an absorbent article including a front panel, a back panel, and a joint portion that joins these panels. This absorbent article is designed so that the dimensions of the front panel are narrower than the dimensions of the back panel, and the dimensions of the front panel are narrower than the dimensions of the back panel, in order to reduce friction on the wearer's skin due to the sealing part and to improve the appearance. It is also shown in the same document that the section is disposed forward from the side edge in the lateral direction of the article toward the center longitudinal direction of the article, and is formed so as to be located at the highest point of the leg opening.

International Application No. 2016/104752 pamphlet International Application No. 2016/108898 pamphlet

By the way, when disposable diapers are used by a wearer, such as an infant, for example, they must be replaced more frequently due to the frequent excretion of excrement. However, it is desirable to have a configuration that allows the person changing the diaper to easily remove it from the wearer's abdomen. It is also desired that such disposable diapers can be manufactured using existing equipment.

However, in the disposable diapers of Patent Documents 1 and 2, no consideration has been given to a structure that can be easily removed from the wearer's abdomen. In addition, the disposable diapers of Patent Documents 1 and 2 have different joint structure and outer package dimensions from those of general disposable diapers, and therefore require a large industrial load such as the introduction of new equipment. , could not increase productivity.

Therefore, an object of the present invention is to provide a disposable diaper that can be easily removed from the wearer's abdomen and that can be manufactured with high production efficiency.

The present invention has a longitudinal direction corresponding to the front-rear direction of the wearer and a width direction perpendicular to the longitudinal direction, and includes a ventral region, a dorsal region, and a crotch region located between these regions, A pants-type disposable diaper comprising an absorbent body disposed in a region from the ventral region to the dorsal region along the longitudinal direction, and an exterior body disposed on the non-skin facing side of the absorbent body. And,
The exterior body includes: a ventral exterior body disposed in the ventral region and stretchable in the width direction; a dorsal exterior body disposed in the dorsal region and stretchable in the width direction; comprising a pair of seal parts that join the widthwise both edges of the exterior body and the dorsal exterior body,
In a natural state, the length in the width direction of the ventral exterior body is shorter than the length in the width direction of the dorsal exterior body,
In a natural state, when viewed in plan with the longitudinal outer edge of the ventral exterior body and the longitudinal outer edge of the dorsal exterior body aligned, the entire area of each seal portion is It is located on the side where the ventral exterior body is located,
When the diaper is cut open along the sealing portion and placed in the unfolded state in which it is stretched to the maximum, the length of the ventral exterior body in the width direction and the length of the dorsal exterior body in the width direction are the same;
The purpose of the present invention is to provide a pants-type disposable diaper in which the breaking strength of the ventral exterior body is higher than the breaking strength of the dorsal exterior body.

According to the present invention, a disposable diaper is provided that can be easily removed from the wearer's abdomen and can be manufactured with high production efficiency.

FIG. 1 is a perspective view schematically showing an embodiment of a pants-type disposable diaper in its natural state. FIG. 2 shows the pant-type disposable diaper shown in FIG. 1 in which the outer longitudinal edge of the ventral exterior body and the longitudinal outer edge of the dorsal exterior body are made to coincide with each other, and the end along the longitudinal direction of the absorbent body. FIG. 4 is a plan view schematically showing a state seen from the ventral exterior body side when viewed from above with edges aligned. FIG. 3 is a developed plan view schematically showing the skin-facing surface side (inner surface side) of the diaper shown in FIG. 1 in the maximum extension and unfolded state. FIG. 4(a) is an enlarged view of main parts schematically showing the ventral exterior body of the diaper shown in FIG. 3, and FIG. 4(b) is a schematic enlarged view of the dorsal exterior body of the diaper shown in FIG. It is an enlarged view of the main part shown. FIG. 5(a) is a cross-sectional view schematically showing the ventral exterior body of the pants-type disposable diaper in its natural state, and FIG. 5(b) is a schematic cross-sectional view of the dorsal exterior body of the pants-type disposable diaper in its natural state. FIG.

Hereinafter, the disposable diaper of the present invention will be explained based on its preferred embodiment. 1 to 3 show an embodiment of the pants-type disposable diaper of the present invention. As shown in FIGS. 1 to 3, a pants-type disposable diaper 1 (hereinafter also simply referred to as "diaper 1") has a ventral region F disposed on the ventral side of the wearer and a ventral region F disposed on the wearer's dorsal side when worn. It has a dorsal region R located between the two regions, and a crotch region M located between these regions. The diaper 1 has a longitudinal direction X extending from the ventral side of the wearer to the back side via the crotch region, and a width direction Y orthogonal thereto, corresponding to the front-back direction of the wearer. The ventral region F, the crotch region M, and the dorsal region R extend continuously along the front-back direction of the wearer.

In this specification, the "skin-facing surface" refers to the surface facing the wearer's skin when the diaper is worn, when focusing on the diaper or its constituent members (e.g., absorbent body), and the "non-skin-facing surface" is the side facing away from the wearer's skin when the diaper is worn. That is, the skin-facing surface is a surface relatively close to the wearer's skin, and the non-skin-facing surface is a surface relatively far from the wearer's skin. "When worn" refers to a state in which the proper wearing position of the diaper is maintained.

As shown in FIG. 1, the diaper 1 includes an absorbent body 2 capable of absorbing and retaining excrement, and an exterior body 3 disposed on the non-skin facing side of the absorbent body 2. The exterior body 3 is a member that forms the outer shape of the diaper 1. The periphery of the exterior body 3 forms the contour lines of the ventral region F and the dorsal region R of the diaper 1, respectively. The exterior body 3 includes a ventral exterior body 3F extending in the width direction Y and disposed in the ventral region F, and a dorsal exterior body 3F extending in the width direction Y and disposed in the dorsal region R, which is separate from this. The absorbent main body 2 is arranged to span over both exterior bodies 3F and 3R arranged at a predetermined interval in the longitudinal direction X. Details of the absorbent main body 2 will be described later.

In the diaper 1, both edges in the width direction Y of the ventral exterior body 3F in the exterior body 3 and both side edges in the width direction Y of the back exterior body 3R are coated with adhesive, heat seal, ultrasonic seal, etc. A pair of seal portions S, S are formed by joining each other by a joining means, thereby connecting the exterior bodies 3F, 3R in an annular manner. The diaper 1 also has a waist opening WH through which the wearer's torso passes, and a pair of leg openings LH through which the wearer's lower legs pass.

As described above, the exterior body 3 includes a ventral exterior body 3F and a separate dorsal exterior body 3R. Each of the exterior bodies 3F and 3R has a plurality of thread-like or band-like elastic members 8 arranged along the width direction Y, so that the exterior bodies 3F and 3R are each configured to be expandable and contractible in the width direction Y. has been done. In the following description, the elastic member 8 disposed on the ventral exterior body 3F is also referred to as the ventral elastic member 81, and the elastic member disposed on the dorsal exterior body 3R is also referred to as the dorsal elastic member 82. Each of the elastic members 81 and 82 may be arranged in a stretched state or in a non-stretched state. From the viewpoint of easily forming the exterior bodies 3F and 3R, which will be described later, to have different lengths in their natural state, it is preferable that each ventral elastic member 81 is disposed in an extended state, and each dorsal elastic member 81 is preferably disposed in an extended state. Preferably, the elastic member 82 is disposed in a non-stretched state. Although the elastic members 81 and 82 shown in FIGS. 1 to 3 are illustrated so that the arrangement intervals are different between the exterior bodies 3F and 3R, the elastic members 81 and 82 in each exterior body 3F and 3R are not limited to this form. The intervals between the members 8 may be the same.

The elastic member 8 is disposed at the periphery of the waist opening WH formed by both the exterior bodies 3F and 3R, so that the exterior body 3 can exhibit elasticity in the width direction Y. In addition, near the pair of leg openings LH, LH, one or more leg elastic members in the form of threads or bands are disposed in the absorbent main body 2 in a stretched state (not shown). A substantially continuous annular leg gather is formed at the opening edge of each of the leg openings LH, LH over the entire circumference thereof.

As shown in FIGS. 1 and 2, in the diaper 1 in its natural state, the length of the ventral exterior body 3F in the width direction Y and the length of the back exterior body 3R in the width direction Y are different. Specifically, in the natural state of the diaper, the length of the ventral exterior body 3F in the width direction Y is configured to be shorter than the length of the back exterior body 3R in the width direction Y. The natural state means a state in which no external force is applied to each elastic member disposed on the exterior body 3 and the exterior body 3 is not stretched. In the natural state, "the length in the width direction of the ventral exterior body is shorter than the length in the width direction of the dorsal exterior body" means that the length in the width direction of the ventral exterior body in the natural state is The arithmetic mean value of the values obtained by measuring three or more times is defined as the arithmetic mean value A1, and the length of the dorsal exterior body in the width direction in the natural state is measured three times or more for one sample. When the arithmetic mean value is the arithmetic mean value A2, it means that the arithmetic mean value A1 is smaller than the value obtained by multiplying the arithmetic mean value A2 by 0.95. That is, it means that the relational expression "arithmetic mean value A1<arithmetic mean value A2×0.95" is satisfied.

Further, as shown in FIG. 2, in its natural state, the diaper 1 has an outer edge in the longitudinal direction When viewed in plan with the edges aligned and the edges along the longitudinal direction It is configured to be located on the side. In FIGS. 1 and 2, the position indicated by the symbol FL coincides with the longitudinal direction X outer edge of the ventral exterior body 3F and the longitudinal direction X outer edge of the back exterior body 3R in the natural state of the diaper 1. and an exterior formed when viewed from above in a state where the edge along the longitudinal direction X on the ventral region side and the edge along the longitudinal direction on the dorsal region side of the absorbent main body 2 are aligned. This is the position of the fold of body 3. In other words, the fold line FL of the exterior body 3 aligns the longitudinal direction X outer edge of the ventral exterior body 3F with the longitudinal direction X outer edge of the back exterior body 3R in the natural state of the diaper 1, and It is formed when the width direction center line in the ventral region of the sex body 2 and the width direction center line in the dorsal region are aligned, and under this condition, the entire area of the pair of seal parts S, S is It is configured to be located on the side where the body 3F is located. By having the ventral exterior body 3F and the seal portion S configured as described above, when the diaper 1 is worn, the ventral exterior body 3F is easily positioned on the wearer's ventral side, and the seal portion S is easily positioned on the wearer's ventral side. Since the diaper can be easily positioned on the person's ventral side, it is possible to both improve the appearance of the diaper and make it easy to remove it.

In the natural state of the diaper, in order to make the length in the width direction Y of the ventral exterior body 3F different from the length in the width direction Y of the dorsal exterior body 3R, for example, the length in the width direction Y of the ventral exterior body 3F is The elongation stress along Y may be configured to be higher than the elongation stress along the width direction Y of the back side exterior body 3R. Details regarding the configuration for changing the elongation stress will be described later.

As shown in FIG. 3, when the diaper 1 is cut open along the sealing part S and the diaper 1 is in the unfolded state in which it is stretched to the maximum, the exterior body 3 has the length in the width direction Y of the ventral exterior body 3F and the length of the dorsal exterior body 3F. The body 3R is designed to have the same length in the width direction Y. "The unfolded state in which the diaper 1 is cut open and stretched to the maximum" means that the diaper 1 is separated at the seal part S to be in the unfolded state, and the diaper 1 in the unfolded state is stretched to its maximum design dimensions (elastic This refers to the state in which the object is expanded until it reaches the same dimensions as when it is expanded into a flat surface, excluding any influences from the members.
When the diaper is cut open and stretched to its maximum extent, "the length of the ventral exterior body and the length of the dorsal exterior body in the width direction are the same" means that the diaper is opened and stretched to its maximum extent. Arithmetic mean value B1 of the values obtained by measuring the length in the width direction of the ventral exterior body in the unfolded state three or more times for each sample, and the dorsal exterior body in the unfolded state with the diaper cut open and stretched to the maximum. The ratio of the arithmetic mean value B2 to the arithmetic mean value B1 (B2/B1) when calculating the arithmetic mean value B2 of the values obtained by measuring the length in the width direction three times or more for one sample. is 0.95 or more and 1.05 or less.

Focusing on the physical properties of the exterior body 3, in the diaper 1, the breaking strength of the ventral exterior body 3F is higher than the tensile strength of the back exterior body 3R.
In detail, the breaking strength of the ventral exterior body 3F is preferably 20 N/25 mm or more, more preferably 25 N/25 mm or more, and preferably 45 N/25 mm or less, still more preferably 40 N/25 mm or less.
Further, the breaking strength of the dorsal exterior body 3R is preferably 15 N/25 mm or more, more preferably 20 N/25 mm or more, and preferably 40 N/25 mm, provided that the breaking strength of the dorsal exterior body 3R is lower than the breaking strength of the ventral exterior body 3F. Below, it is more preferably 35N/25mm or less.
In order to create a difference in the breaking strength of the exterior bodies 3F and 3R, for example, the constituent material of the ventral exterior body 3F is made larger than that of the dorsal exterior body 3R, or the constituent material of the ventral exterior body 3F is By making the basis weight of the dorsal exterior body 3R higher than the basis weight of the constituent material of the dorsal exterior body 3R, or by providing a region with a low basis weight or perforations in the constituent material of the dorsal exterior body 3R, a part that is easy to break is created. This can be done by doing.

The breaking strength of each exterior body 3F, 3R can be measured by a tensile test according to JIS P8113 using a tensile compression tester (AG-IS, manufactured by Shimadzu Corporation). Specifically, a measurement sample of 200 mm in length x 25 mm in width is taken from each of the ventral exterior body 3F and the dorsal exterior body 3R so that the longitudinal direction of the measurement sample and the width direction Y of the diaper 1 coincide with each other. Cut out. Using a 50N load cell, the distance between the chucks is 180mm, and the sample is pulled at a tensile rate of 20mm/min so as to extend in the longitudinal direction X, and the maximum load at breakage is measured. Five measurement samples are prepared for one measurement target site, the maximum load of each is measured, and the arithmetic mean value thereof is defined as the breaking strength (N/25 mm) in the present invention.

Returning to the explanation regarding the constituent members of the diaper 1, the absorbent body 2 has a rectangular shape extending along the longitudinal direction X when viewed from above, as shown in FIG. 3, and has a ventral region F. It extends in the longitudinal direction X over the dorsal region R from the dorsal region R. The absorbent main body 2 is joined to the center portion in the width direction Y of each of the ventral exterior body 3F and the dorsal exterior body 3R by a joining means such as an adhesive.

As shown in FIG. 3, the absorbent main body 2 includes a liquid-permeable top sheet 21 that forms the skin-facing surface of the diaper 1, and a liquid-impermeable or liquid-impermeable leakproof sheet that forms the non-skin-facing surface. It includes a sheet 22 and a liquid-retaining absorbent body 23. Like the absorbent main body 2, the absorbent core 23 has a long shape in the longitudinal direction X of the diaper 1, and is interposed between the top sheet 21 and the leak-proof sheet 22. The top sheet 21 and the leak-proof sheet 22 cover the entire surface of the absorbent body 23 and are bonded to the outside of the side edge along the longitudinal direction X of the absorbent body 23 by a known bonding means such as an adhesive.

The absorbent body 23 typically includes an absorbent core and a core wrap sheet that covers the absorbent core (not shown). The absorbent core is composed of a fiber stack of hydrophilic fibers such as pulp fibers, or a fiber stack containing a water-absorbing polymer. Core wrap sheets are made of tissue paper or water-permeable nonwoven fabric. The core wrap sheet preferably covers the entire skin-facing side and non-skin-facing side of the absorbent core.

A pair of leak-proof cuffs 24, 24 made of liquid-resistant or water-repellent and breathable sheets are provided on both sides of the skin-facing surface of the absorbent main body 2 along the longitudinal direction X. Near the free end of each leak-proof cuff 24, one or more thread-like leak-proof cuff-forming elastic members 25 are disposed in an extended state along the longitudinal direction X. The leak-proof cuff 24 stands up at least in the crotch region M when the elastic member 25 arranged in a stretched state contracts when the diaper 1 is worn, thereby preventing excrement such as urine from flowing outward in the width direction Y. to prevent

As the top sheet 21, the leak-proof sheet 22, and the absorbent body 23, those conventionally used in disposable diapers can be used without particular limitation. For example, various nonwoven fabrics, perforated films, and the like can be used as the topsheet 21. As the leak-proof sheet 22, a resin film, a laminate of a resin film and a nonwoven fabric, etc. can be used. The absorbent body 23 can use, as an absorbent core, an aggregate of hydrophilic fibers such as wood pulp or hydrophilic synthetic fibers, or an aggregate in which a water-absorbing polymer is retained in the aggregate. As the wrap sheet, the same one as the top sheet 21 can be used. Further, as the sheet for forming the leak-proof cuff, the same sheet as the leak-proof sheet 22 can be used.

In the diaper 1 having the above configuration, in its natural state, the length of the ventral exterior body 3F in the width direction Y is shorter than the length of the back exterior body 3R in the width direction Y, and the seal portion S is located on the ventral side of the wearer, so the appearance of the diaper 1 is good when the diaper is worn.
In addition to this configuration, by making the breaking strength along the longitudinal direction X of the ventral exterior body 3F higher than the breaking strength along the longitudinal direction When removing the diaper 1, if you grasp the ventral exterior body 3F located on the ventral side of the wearer and pull it in the direction away from the wearer, the seal portion S or the dorsal side located near the seal portion S In the exterior body 3R, breakage is likely to occur along the extending direction of the seal portion S. As a result, even if the wearer, such as an infant, is in a position that would normally make it difficult to remove a pants-type diaper, such as in a supine or sitting position, the person changing the diaper can pull the ventral exterior body 3F to remove the wearer's diaper. The diaper can be easily removed from the abdomen.
Furthermore, since the outer packaging bodies 3F and 3R constituting the diaper 1 have the same design dimensions in the width direction, they can be manufactured using existing pants-type disposable diaper manufacturing equipment as is. As a result, diapers can be manufactured with high production efficiency while preventing increases in production costs such as the introduction of new equipment.

From the viewpoint of making the above-mentioned effects noticeable, when the ventral exterior body 3F and the dorsal exterior body 3R are each extended to have the same length along the width direction Y, the ventral exterior body 3F It is preferable that the elongation stress along the width direction Y of the back side exterior body 3R is higher than the elongation stress along the width direction Y of the back side exterior body 3R. In particular, with such a configuration, the ventral exterior body 3F and the seal portion S where the exterior bodies 3F and 3R are joined are easily positioned on the wearer's abdomen, so that the diaper 1 when worn is easily positioned on the wearer's abdomen. The appearance of the diaper 1 is further improved, and the person changing the diaper can more easily remove the diaper 1 from the wearer's abdomen.

The elongation stress in each of the exterior bodies 3F and 3R can be measured by the following method. First, the diaper 1 to be measured is cut open and expanded to its maximum extent, and the elastic members 8 are arranged along the width direction Y from each of the ventral exterior body 3F and the dorsal exterior body 3R. Cut out the area that is present and use it as a measurement sample. The measurement sample is cut out into a rectangular shape with a length of 70 mm and a width of 25 mm, and cut out so that the width direction Y of the diaper 1 and the longitudinal direction of the measurement sample coincide. When cutting out, the exterior body 3 from which the absorbent body 2 and the like have been removed is targeted. Both ends of the cut out measurement sample in the longitudinal direction were held between chucks of a Tensilon tensile tester ("RTC-1210A" manufactured by ORIENTEC), and the measurement sample was stretched in the longitudinal direction at a speed of 300 mm/min to cut out the measurement sample. The tensile load when elongated to 130% of the original length is defined as elongation stress (N/mm).

The elongation stress F1 along the width direction Y of the ventral exterior body 3F measured by the above-mentioned measuring method is preferably 0.2 N/mm or more, more preferably 0.8 N/mm or more, and preferably 3. It is 0 N/mm or less, more preferably 2.5 N/mm or less.
Further, under the same conditions, the elongation stress R1 of the back exterior body 3R along the width direction Y is preferably 0.1 N/mm or more, more preferably 0.5 N/mm or more, and preferably 2.0 N/mm or less, More preferably, it is 1.5 N/mm or less.
Under the same conditions, the difference (F1-R1) between the extension stress F1 of the ventral exterior body 3F and the extension stress R1 of the dorsal exterior body 3R is preferably 0.1 N/mm or more, more preferably 0.5 N/mm. mm or more, preferably 2.4 N/mm or less, more preferably 2.0 N/mm or less.

In order to configure the elongation stress F1 along the width direction Y of the ventral side exterior body 3F and the elongation stress R1 along the width direction Y of the dorsal side exterior body 3R to be different, for example, the following configurations may be used. I can do it.

Specifically, the diaper 1 is configured to make the expansion magnification F2 of the ventral elastic member 81 in the ventral exterior body 3F higher than the expansion magnification R2 of the dorsal elastic member 82 in the dorsal exterior body 3R. is preferred. With this configuration, the elongation stress of the ventral exterior body 3F and the dorsal exterior body 3R can be easily changed to fall within desired ranges, and as a result, the wearer's abdominal A diaper 1 from which the diaper can be easily removed from the side can be manufactured with high productivity. In particular, the above-mentioned difference in elongation magnifications F2 and R2 is satisfied when thread-like rubber made of polyurethane resin is used as the ventral elastic member 81, and styrene-based elastomer, which will be described later, is used in thread-like form as the back-side elastic member 82. It is preferable that the diaper be made of the same material, from the viewpoint that a diaper that can be easily removed from the wearer's abdomen can be manufactured with higher productivity.

The elongation magnification of each elastic member 81, 82 can be measured, for example, by the following method. First, the ventral elastic member 81 and the dorsal elastic member 82 disposed on each of the exterior bodies 3F and 3R are taken out and stretched to the maximum in the width direction Y, and each elastic member 81, 82, use an oil marker to make two marks at a constant interval L1 in the direction of expansion and contraction. Next, each elastic member 81, 82 is cut out from each exterior body 3F, 3R between the two marks. The length L2 of this cut out elastic member is measured in a non-stretched state. This measurement is performed three times for each of the exterior bodies 3F and 3R, and the elongation magnification (times) is determined from the arithmetic mean value of the values calculated by the formula "L1/L2". The interval L1 can be, for example, 100 mm.

The elongation magnification F2 of the ventral elastic member 81 in the ventral exterior body 3F, measured by the above-mentioned measuring method, is preferably 2.2 times or more, more preferably 2.5 times or more, and preferably 4.3 times. It is not more than 4.0 times, more preferably not more than 4.0 times. Further, under the same conditions, the elongation magnification R2 of the dorsal elastic member 82 in the dorsal exterior body 3R is preferably 1.5 times or more, more preferably 2.0 times or more, and preferably 4.1 times or less, even more preferably is 3.8 times or less.

Instead of or in addition to the above-described form, the thickness F3 of the ventral elastic member 81 in the ventral exterior body 3F is made thicker than the thickness R3 of the dorsal elastic member 82 in the dorsal exterior body 3R. It is also preferable that the extension stress F1 along the width direction Y of the ventral exterior body 3F and the extension stress R1 along the width direction Y of the dorsal exterior body 3R be configured to be different. With such a configuration, the elongation stress of the ventral exterior body 3F and the dorsal exterior body 3R can be easily changed to fall within desired ranges, and as a result, the wearer's A diaper 1 from which the diaper can be easily removed from the abdominal side can be manufactured with high productivity. In particular, the difference between the thicknesses F3 and R3 of the elastic members 81 and 82 described above is due to the fact that the ventral elastic member 81 is made of polyurethane resin string rubber, and the back elastic member 82 is made of styrene elastomer, which will be described later. It is preferable that the condition is satisfied when the condition is used in the form of a diaper, from the viewpoint of producing a diaper that can be easily removed from the wearer's abdomen with higher productivity.

The thickness of each elastic member 81, 82 mentioned above refers to the thickness of each elastic member in a non-stretched state. When each elastic member 81, 82 is thread-like, the thickness of each elastic member 81, 82 is determined by measuring the cross-sectional diameter of three different elastic members, and is expressed as the arithmetic average value. When each elastic member 81, 82 is in the shape of a band, the thickness of each elastic member 81, 82 is determined by measuring the length perpendicular to the stretching direction on the main surface of the elastic member for three different elastic members, and Expressed as an average value. When each of the elastic members 81 and 82 is composed of a bundle of a plurality of elastic fibers, a sample is obtained by cutting out the elastic member at a certain length (e.g. 100 mm) from the exterior body to be measured. The thickness (fineness) of the elastic member may be expressed by dividing the mass of the sample by the length of the sample.

The thickness F3 of the ventral elastic member 81 in the ventral exterior body 3F, which is measured in the above measurement method, is preferably 100 μm or more, more preferably 200 μm or more, and preferably 600 μm or less, and even more preferably 500 μm or less. be.
Further, under the same conditions, the thickness R3 of the dorsal elastic member 82 in the dorsal exterior body 3R is preferably 30 μm or more, more preferably 50 μm or more, provided that it is smaller than the thickness F3 of the ventral elastic member 81. , preferably 500 μm or less, more preferably 400 μm or less.

Moreover, instead of or in addition to the above-described form, the distance F4 between the ventral elastic members 81 adjacent in the longitudinal direction X in the ventral exterior body 3F is set to The spacing R4 between the elastic members 82 is made larger, and the extensional stress F1 along the width direction Y of the ventral exterior body 3F is configured to be different from the extensional stress R1 along the width direction Y of the dorsal exterior body 3R. is also preferable. With such a configuration, the elongation stress of the ventral exterior body 3F and the dorsal exterior body 3R can be easily changed to fall within desired ranges, and as a result, the wearer's A diaper 1 from which the diaper can be easily removed from the abdominal side can be manufactured with high productivity. In particular, the difference in the distances F4 and R4 between the elastic members 81 and 82 described above is determined by using thread-like rubber made of polyurethane resin as the ventral elastic member 81 and using a styrene elastomer (described later) in thread-like form as the back-side elastic member 82. It is preferable that the condition be satisfied when the diaper is used in the following conditions, from the viewpoint of producing a diaper that can be easily removed from the wearer's abdomen with higher productivity.

Specifically, the interval F4 (see FIG. 4(a)) between adjacent ventral elastic members 81 in the longitudinal direction X in the ventral exterior body 3F is preferably 3 mm or more, more preferably 5 mm or more, and preferably 30 mm. It is more preferably 25 mm or less. Further, in the dorsal exterior body 3R, the interval R4 (see FIG. 4(b)) between the dorsal elastic members 82 adjacent to each other in the longitudinal direction is 0.5 mm or more, preferably 5 mm or less, and more preferably 3 mm or less.

In addition, instead of or in addition to the above-described form, the resin constituting the ventral elastic member 81 in the ventral exterior body 3F and the resin constituting the dorsal elastic member 82 in the dorsal exterior body 3R have different elasticity. It is also preferable that the extension stress F1 along the width direction Y of the ventral exterior body 3F and the extension stress R1 along the width direction Y of the dorsal exterior body 3R be different. In particular, it is more preferable that the elastic modulus F5 of the resin constituting the ventral elastic member 81 is higher than the elastic modulus R5 of the resin constituting the dorsal elastic member 82. With such a configuration, the elongation stress of the ventral exterior body 3F and the dorsal exterior body 3R can be easily changed to fall within desired ranges, and as a result, the wearer's A diaper 1 from which the diaper can be easily removed from the abdominal side can be manufactured with high productivity. The difference between the elastic moduli F5 and R5 mentioned above is due to the fact that the elastic members 81 and 82 have the same thickness, the elongation magnifications F2 and R2 are the same, and the elastic members 81 and 82 are the same, and the elastic members 81 and 82 are the same, and the elastic members 81 and 82 are the same, and the elastic members 81 and 82 are the same in size, It is assumed that the interval between matching ventral elastic members 81 and the interval between adjacent dorsal elastic members 82 disposed on the dorsal exterior body 3R are the same.

Examples of the above-mentioned constituent resin include natural rubber, EVA rubber, styrene-butadiene rubber, butadiene rubber, synthetic rubber such as isoprene rubber and neoprene rubber, polyurethane, and thermoplastic elastomer. Examples of thermoplastic elastomers include SBS (styrene-butadiene-styrene), SIS (styrene-isoprene-styrene), SEBS (styrene-ethylene-butadiene-styrene), and SEPS (styrene-ethylene-propylene-styrene). Examples include styrene-based elastomers, ethylene-based α-olefin elastomers, olefin-based elastomers such as propylene-based elastomers copolymerized with ethylene, butene, octene, etc., polyester-based elastomers, and polyurethane-based elastomers. These constituent resins can be used alone or in combination of two or more.

Of these, each of the elastic members 81, 82 It is preferable to use different constituent resins. From the same viewpoint, it is more preferable that the ventral elastic member 81 uses polyurethane as its constituent resin. From the same viewpoint, it is more preferable that the back side elastic member 82 uses a thermoplastic elastomer as its constituent resin, it is even more preferable to use at least one of a styrene elastomer and an olefin elastomer, and it is more preferable to use SEBS or SEPS. is particularly preferred.

The above-mentioned elongation stress was obtained by comparing the ventral exterior body 3F and the dorsal exterior body 3R. When focusing on the ventral exterior body 3F or the dorsal exterior body 3R, respectively, the exterior body 3 is , it is preferable to have regions with different elongation stresses.

Specifically, as shown in FIGS. 4(a) and 4(b), in each exterior body 3F, 3R, a virtual line L1 passing through the longitudinal end 2a of the absorbent body 2 and extending along the width direction Y is drawn. think. At this time, the extension stress along the width direction Y of the part 3m (hereinafter also referred to as "crotch side part 3m") located closer to the crotch area M than the imaginary line L1 of the exterior body 3 is applied to the exterior body 3. The elongation stress is higher than the elongation stress along the width direction Y of the region 3s located closer to the longitudinal end 1a of the diaper 1 than the imaginary line L1 in No. 3 (hereinafter also referred to as "end region 3s"). It is preferable that With this configuration, even if the wearer of the diaper 1, such as an infant, changes in abdominal circumference due to eating or movement, discomfort caused by the tightening of the abdomen by the exterior body 3 can be prevented. In addition, since the diaper 1 is less likely to slip off, the usability of the diaper 1 can be improved.
In order to achieve the above-mentioned configuration, for example, the elastic member in the crotch side portion 3m may be configured to have a higher expansion magnification than the elastic member in the end portion 3s, or the thickness of the elastic member 8 may be made thicker. This can be done by configuring the elastic members 8 to be narrower, or by configuring the elastic members 8 to narrow the distance between them in the longitudinal direction X.

To explain the structure of the exterior body 3, as shown in FIG. 5, the ventral exterior body 3F includes a ventral outer layer sheet 31 that forms the non-skin facing surface of the diaper 1 located on the ventral side of the wearer in the worn state. , a laminate including a ventral outer layer sheet 31 and a ventral inner layer sheet 32 disposed on the skin-facing surface. When the diaper 1 is worn, the ventral outer layer sheet 31 forms the non-skin facing surface of the diaper 1 and also constitutes the outer surface of the diaper 1. On the other hand, the ventral inner layer sheet 32 forms the skin facing surface of the diaper 1. The ventral outer layer sheet 31 and the ventral inner layer sheet 32 are intermittently joined to each other at predetermined locations via joints 35 formed by a joining means such as an adhesive. The region defined by the ventral outer layer sheet 31 and the ventral inner layer sheet 32 is preferably hollow, and uneven folds are formed in the natural state of the ventral exterior body 3F. A plurality of the above-mentioned ventral elastic members 81 are arranged between the ventral outer layer sheet 31 and the ventral inner layer sheet 32, and each ventral elastic member 81 is arranged between the ventral outer layer sheet 31 and the ventral inner layer sheet 32. It is clamped and fixed between 32 and 32.

Further, as shown in FIG. 5, the back exterior body 3R includes a back outer layer sheet 36 that forms the non-skin facing surface of the diaper 1 located on the back side of the wearer in the worn state, and a skin of the back outer layer sheet 36. It is configured to include a laminate with a back inner layer sheet 37 disposed on the opposing surface. When the diaper 1 is worn, the back outer layer sheet 36 forms the non-skin facing surface of the diaper 1 and also constitutes the outer surface of the diaper 1, similarly to the ventral outer layer sheet 31. On the other hand, the back inner layer sheet 37 forms the skin facing surface of the diaper 1. The back outer sheet 36 and the inner back sheet 37 are intermittently joined to each other at predetermined locations via joints 35 formed by a joining means such as an adhesive. The region defined by the back outer layer sheet 36 and the back inner layer sheet 37 is preferably hollow, and in the natural state of the back side exterior body 3R, it has an uneven shape having a plurality of alternating convex portions and concave portions. Folds are formed. The back outer layer sheet 36 in this embodiment is in the form of a stretchable sheet, which will be described later.

When each of the exterior bodies 3F and 3R is viewed in cross section in its natural state, the thickness F8 of the ventral exterior body 3F (see FIG. 5(a)) is equal to the thickness R8 of the dorsal exterior body 3R (see FIG. 5(b)). It is preferable that it is larger than . With this configuration, when the diaper 1 is worn, sufficient air permeability is ensured in and around the area where the ventral exterior body 3F and the wearer's abdomen contact, and the diaper is not worn. It is possible to prevent stuffiness caused by the diaper and improve the usability of the diaper. In particular, as mentioned above, when the ventral exterior body 3F is formed of two sheets, the uneven structure of the folds is formed to be large, and the inside of the convex part is hollow, so that breathability is improved. becomes even higher, and the usability of the diaper can be further improved.

Furthermore, with the above-described configuration, when the diaper 1 is worn, even if the wearer is in a supine position or the like, and the back exterior body 3R is pressed against the wearer's back. In the area where the back side exterior body 3R contacts the back of the wearer and in the vicinity thereof, the wearer is less likely to leave wear marks of the diaper 1 due to the surface shape of the back side exterior body 3R, such as folds. In particular, as described above, when the dorsal exterior body 3R is formed of two sheets, the unevenness of the folds formed on the dorsal exterior body 3R is formed on the ventral exterior body 3F. Since the unevenness is smaller than the unevenness of the folds, it becomes even more difficult for the wearer to be left with wear marks of the diaper 1 due to the folds.

The thickness F8 (see FIG. 5(a)) of the ventral exterior body 3F in a natural state is preferably 2 mm or more, more preferably 3 mm or more, and preferably 10 mm or less, and even more preferably 8 mm or less. Further, the thickness R8 (see FIG. 5(b)) of the dorsal exterior body 3R in its natural state is preferably 0.5 mm or more, more preferably 1.5 mm or more, and preferably 8 mm or less, and even more preferably 6 mm or less. It is.

To explain the configuration of the back side exterior body 3R, it is preferable that the stretchable sheet 3A is used as a sheet constituting the back side exterior body 3R, and the stretchable sheet 3A is configured as the back side outer layer sheet 36. It is even more preferable that In this case, it is more preferable that the back inner layer sheet 37 is composed of a non-stretchable sheet such as various nonwoven fabrics described below. By having such a configuration, the flexibility of the dorsal exterior body 3R is increased, so even if the dorsal exterior body 3R is pressed against the back of the wearer, folds etc. It becomes more difficult for the wearer to get wear marks on the diaper 1 due to the surface shape of the side exterior body 3R.

Specifically, the elastic sheet 3A constituting the back exterior body 3R has a plurality of back elastic members 82 arranged in a non-stretched state so as to extend in one direction without intersecting each other. Preferably, it is bonded to a non-woven fabric that can be used. In this embodiment, the elastic sheet 3A is composed of two nonwoven fabrics 3c and 3d and a back elastic member 82 bonded and disposed between both nonwoven fabrics 3c and 3d, and is elastic in the width direction Y. It is arranged so that it has a gender.

Further, when the elastic sheet 3A is used as the sheet constituting the back side exterior body 3R, the sheet has a low basis weight portion 3j extending along the longitudinal direction X of the diaper 1 (in the front-rear direction of the paper in FIG. It is also preferable that high basis weight portions 3k extending along the longitudinal direction X and having a higher basis weight than the low basis weight portions are alternately formed along the width direction Y. By having such a structure, in addition to making it difficult for the wearer to be left with wear marks of the diaper 1, when the stretchable sheet 3A is viewed microscopically, the breaking strength in the low basis weight portion 3j is high. Since the breaking strength is smaller than the breaking strength of the low basis weight part 3k, breakage is likely to occur from the low basis weight part 3j in the sealing part S or the back side exterior body 3R located near the sealing part S. The diaper can be more easily removed from the ventral side of the diaper.

As shown in FIG. 5(b), the basis weight portions 3j, 3k are formed alternately along a direction perpendicular to the direction in which the back elastic member 82 extends. The low basis weight portions 3j and the high basis weight portions 3k are arranged alternately at a constant period. In a cross-sectional view of the stretchable sheet 3A, both the front and back sides of the stretchable sheet 3A have complementary wavy shapes. In the elastic sheet 3A, concave portions on the other surface are located at positions of convex portions on one surface thereof. Moreover, at the position of the concave portion on one surface of the elastic sheet 3A, a convex portion on the other surface is located. Further, as shown in FIG. 5(b), when the elastic sheet 3A is viewed along the width direction Y, low basis weight portions 3j are formed at the positions of the convex portions and concave portions, and the adjacent convex portions A high basis weight portion 3k is formed at a position between the and the recessed portions.

The elastic sheet used in the sheet constituting the back side exterior body 3R includes, for example, a substantially inelastic inelastic fibrous layer arranged on at least one surface of an elastic fibrous layer made from the above-mentioned thread-like or band-like elastic member. , laminated nonwoven fabrics joined by thermal fusion while maintaining their fiber morphology, stretch sheets described in JP-A-2008-179128 and JP-A-2007-22066, and the like can be used. As the back side elastic member 82 in this case, fibers made from thermoplastic elastomers such as the above-mentioned styrene elastomers, olefin elastomers, polyester elastomers, and polyurethane elastomers, and elastic resins such as rubber can be used.

The nonwoven fabrics used for the ventral outer sheet 31, the ventral inner sheet 32, the dorsal outer sheet 36, and the dorsal inner sheet 37 are known, such as spunbond nonwoven fabric, thermal bond nonwoven fabric, spunlace nonwoven fabric, meltblown nonwoven fabric, and air-through nonwoven fabric. Any nonwoven fabric can be used without particular limitation. Moreover, when using the elastic sheet 3A mentioned above for the back inner layer sheet 37, the above-mentioned nonwoven fabric can be used as a constituent material of the elastic sheet 3A.

In the diaper 1, when the exterior body 3 is stretched in the width direction Y to reach the expected waist circumference of the wearer, the stretching stress along the width direction Y in the ventral exterior body 3F and the width direction in the dorsal exterior body 3R It is preferable that the elongation stress along Y is the same. With such a configuration, the length in the width direction Y of the ventral exterior body 3F in the natural state and the length in the width direction Y of the dorsal exterior body 3R in the natural state may be different from each other, or the length in the width direction Y of the ventral exterior body 3F in the natural state may be different from each other. Even if the elongation stress along the width direction Y of the side exterior body 3F and the elongation stress along the width direction Y of the back side exterior body 3R are different from each other, when wearing the diaper, the wearer's waist circumference By allowing the diaper 1 to develop elasticity substantially uniformly, it is possible to reduce slippage and twisting when the diaper 1 is worn.

The intended waist circumference of the wearer is changed as appropriate depending on the design of the diaper 1 and the intended wearer, but typically, the expected waist circumference length is when the outer body 3 is stretched to the maximum and the designed dimension is set. It refers to a length whose ratio to the circumference is 80% or more and 90% or less. For example, when the circumferential length of the exterior body 3 is 560 mm when the exterior body 3 is expanded to the maximum and is set to the design dimension, the planned abdominal circumference length can be 448 mm or more and 504 mm or less. Under these conditions, the length in the width direction Y of the ventral exterior body 3F and the length in the width direction Y of the dorsal exterior body 3R are as follows: What is necessary is to measure the length of 3F and 3R in the width direction.

When the exterior body 3 is stretched to the intended waist circumference of the wearer, the stretching stress Rp along the width direction Y in the dorsal exterior body 3R is expressed as a ratio to the stretching stress Fp along the width direction Y in the ventral exterior body 3F. If it is 90% or more, it can be considered as "equivalent" in the present invention.

When stretched to the intended abdominal girth of the wearer, the stretching stress Fp along the width direction Y in the ventral exterior body 3F is preferably 0.2 N/mm or more, more preferably 0.8 N/mm or more, and preferably is 3.0 N/mm or less, more preferably 2.5 N/mm or less.
Further, the elongation stress Rp along the width direction Y in the back exterior body 3R is preferably 0.1 N/mm or more, more preferably 0.5 N/mm or more, and preferably 2.0 N/mm or less, even more preferably is 1.5 N/mm or less.

Although the present invention has been described above based on its preferred embodiments, the present invention is not limited to the above-described embodiments.

Regarding the embodiment of the present invention described above, the following pants-type disposable diaper is further disclosed.
<1>
A crotch region having a longitudinal direction corresponding to the front-back direction of the wearer and a width direction perpendicular to the longitudinal direction, and having a ventral region and a dorsal region, and a crotch region located between the ventral region and the dorsal region. and an absorbent body disposed in a region from the ventral region to the dorsal region along the longitudinal direction, and an exterior body disposed on the non-skin-facing side of the absorbent body. It is a pants-type disposable diaper,
The exterior body includes: a ventral exterior body disposed in the ventral region and stretchable in the width direction; a dorsal exterior body disposed in the dorsal region and stretchable in the width direction; a pair of seal portions that join the side edges in the width direction of the exterior body and the side edges in the width direction of the dorsal exterior body;
In a natural state, the length of the ventral exterior body in the width direction is shorter than the length of the dorsal exterior body in the width direction,
In a natural state, the longitudinal outer edge of the ventral exterior body and the longitudinal outer edge of the dorsal exterior body are aligned, and the absorbent main body has an edge along the longitudinal direction. When viewed from above in a state where they are matched, the entire area of each seal portion is located on the side where the ventral exterior body is located,
When the diaper is cut open along the sealing portion and placed in the unfolded state in which it is stretched to the maximum, the length of the ventral exterior body in the width direction and the length of the dorsal exterior body in the width direction are the same. ,
A pants-type disposable diaper, wherein the breaking strength of the ventral exterior body is higher than the breaking strength of the dorsal exterior body.

<2>
The pants-type disposable diaper according to <1> above, wherein the abdominal exterior body has a breaking strength of 20 N/25 mm or more and 45 N/25 mm or less, preferably 25 N/25 mm or more and 40 N/25 mm or less.
<3>
The pants-type disposable diaper according to <1> or <2>, wherein the breaking strength of the back side exterior body is 15 N/25 mm or more and 40 N/25 mm or less, preferably 20 N/25 mm or more and 35 N/25 mm or less.
<4>
When the ventral exterior body and the dorsal exterior body are each extended to the same length along the width direction, the stretching stress along the width direction of the ventral exterior body is The pants-type disposable diaper according to any one of <1> to <3>, which is higher than the elongation stress along the width direction of the outer package.
<5>
In <4> above, the elongation stress along the width direction of the ventral exterior body is 0.2 N/mm or more and 3.0 N/mm or less, preferably 0.8 N/mm or more and 2.5 N/mm or less. Pants-type disposable diaper as described.

<6>
or <4> above, wherein the elongation stress of the dorsal exterior body along the width direction is 0.1 N/mm or more and 2.0 N/mm or less, preferably 0.5 N/mm or more and 1.5 N/mm or less; The pants-type disposable diaper according to <5>.
<7>
The difference (F1-R1) between the extension stress F1 of the ventral exterior body and the extension stress R1 of the dorsal exterior body is 0.1 N/mm or more and 2.4 N/mm or less, preferably 0.5 N/mm or more. The pants-type disposable diaper according to any one of <4> to <6> above, which has a pressure of 2.0 N/mm or less.
<8>
Both the ventral exterior body and the dorsal exterior body include thread-like or band-like elastic members,
By making the elongation magnification of the elastic member in the ventral exterior body higher than the elongation magnification of the elastic member in the dorsal exterior body, the elongation stress along the width direction of the ventral exterior body is The pants-type disposable diaper according to any one of <4> to <7>, which is formed to have a higher elongation stress in the width direction of the side exterior body.

<9>
The pants-type disposable according to <8>, wherein the elastic member in the ventral exterior body has an elongation factor of 2.2 times or more and 4.3 times or less, preferably 2.5 times or more and 4.0 times or less. Diapers.
<10>
As described in <8> or <9> above, the elongation magnification of the elastic member in the dorsal exterior body is 1.5 times or more and 4.1 times or less, preferably 2.0 times or more and 3.8 times or less. Pants-type disposable diaper.
<11>
Both the ventral exterior body and the dorsal exterior body include thread-like or band-like elastic members,
By making the thickness of the elastic member in the ventral exterior body thicker than the thickness of the elastic member in the dorsal exterior body, the elongation stress along the width direction of the ventral exterior body is applied to the dorsal exterior body. The pants-type disposable diaper according to any one of <4> to <10>, which is formed to have a higher elongation stress in the width direction of the outer package.
<12>
The pants-type disposable diaper according to <11> above, wherein the elastic member in the ventral exterior body has a thickness of 100 μm or more and 600 μm or less, preferably 200 μm or more and 500 μm or less.

<13>
The pants-type disposable diaper according to <11> or <12>, wherein the elastic member in the back side exterior body has a thickness of 30 μm or more and 500 μm or less, preferably 50 μm or more and 400 μm or less.
<14>
Both the ventral exterior body and the dorsal exterior body include thread-like or band-like elastic members extending in the width direction and arranged in plurality along the longitudinal direction,
By making the interval between the elastic members adjacent in the longitudinal direction in the ventral exterior body larger than the interval between the elastic members adjacent in the longitudinal direction in the dorsal exterior body, the The pants-type disposable according to any one of <4> to <13>, wherein the stretching stress along the width direction is higher than the stretching stress along the width direction of the dorsal exterior body. Diapers.
<15>
The pants-type disposable diaper according to <14>, wherein a distance between the elastic members adjacent in the longitudinal direction in the abdominal exterior body is 3 mm or more and 30 mm or less, preferably 5 mm or more and 25 mm or less.

<16>
The pants type according to <14> or <15>, wherein a distance between the elastic members adjacent in the longitudinal direction in the back side exterior body is 0.2 mm or more and 5 mm or less, preferably 0.5 mm or more and 3 mm or less. disposable diapers.
<17>
Both the ventral exterior body and the dorsal exterior body include thread-like or band-like elastic members,
By configuring each of the elastic members with resins having different moduli of elasticity, the stretching stress along the width direction of the ventral exterior body is made higher than the stretching stress along the width direction of the dorsal exterior body. The pants-type disposable diaper according to any one of the above items <4> to <16>, which is formed as follows.
<18>
The elastic member of the ventral exterior body is made of polyurethane resin,
The elastic member of the back exterior body is a thermoplastic elastomer, preferably at least one of a styrene elastomer and an olefin elastomer, more preferably SEBS or SEPS, as described in <17> above. Pants-type disposable diaper.

<19>
When considering an imaginary line passing through the longitudinal end of the absorbent body and extending along the width direction, the elongation stress along the width direction of the exterior body located closer to the crotch region than the imaginary line is , the elongation stress according to any one of <1> to <18> above, which is higher than the elongation stress along the width direction of the exterior body located closer to the longitudinal end of the disposable diaper than the imaginary line. Pants-type disposable diaper.
<20>
The pants-type disposable diaper according to any one of <1> to <19>, wherein the thickness of the ventral exterior body is greater than the thickness of the dorsal exterior body in a natural state.
<21>
The pants-type disposable diaper according to <20>, wherein the ventral exterior body is formed of two sheets, the folds have a large uneven structure, and the inside of the convex portion is hollow.
<22>
The pants-type disposable diaper according to <20> or <21>, wherein the thickness of the ventral exterior body in a natural state is 2 mm or more and 10 mm or less, preferably 3 mm or more and 8 mm or less.

<23>
The pants-type disposable diaper according to any one of <20> to <22>, wherein the thickness of the back side exterior body in a natural state is 0.5 mm or more and 8 mm or less, preferably 1.5 mm or more and 6 mm or less.
<24>
The back side exterior body includes a low basis weight portion extending along the longitudinal direction and a high basis weight portion extending along the longitudinal direction and having a higher basis weight than the low basis weight portion along the width direction. The pants-type disposable diaper according to any one of <1> to <23> above, comprising sheets alternately formed.
<25>
The dorsal exterior body is made up of a plurality of elastic members arranged in a non-stretched state so as to extend in one direction without intersecting each other, and joined to a nonwoven fabric that is stretchable over the entire length of the plurality of elastic members. The pants-type disposable diaper according to any one of <1> to <24> above, comprising an elastic sheet.
<26>
When the exterior body is stretched in the width direction so as to have the expected waist circumference of the wearer, an elongation stress along the width direction in the ventral exterior body and an elongation along the width direction in the dorsal exterior body. The pants-type disposable diaper according to any one of <1> to <25> above, which has the same stress.

1 Pants-type disposable diaper 2 Absorbent body 3 Exterior body 3F Ventral exterior body 3R Dorsal exterior body 8 Elastic member 81 Ventral elastic member 82 Dorsal elastic member F Ventral region M Inseam region R Dorsal region S Seal portion X Longitudinal direction Y Width direction

Claims (10)

A crotch region having a longitudinal direction corresponding to the front-back direction of the wearer and a width direction perpendicular to the longitudinal direction, and having a ventral region and a dorsal region, and a crotch region located between the ventral region and the dorsal region. and an absorbent body disposed in a region from the ventral region to the dorsal region along the longitudinal direction, and an exterior body disposed on the non-skin-facing side of the absorbent body. It is a pants-type disposable diaper,
The exterior body includes: a ventral exterior body disposed in the ventral region and stretchable in the width direction; a dorsal exterior body disposed in the dorsal region and stretchable in the width direction; a pair of seal portions that join the side edges in the width direction of the exterior body and the side edges in the width direction of the dorsal exterior body;
In a natural state, the length of the ventral exterior body in the width direction is shorter than the length of the dorsal exterior body in the width direction,
In a natural state, the longitudinal outer edge of the ventral exterior body and the longitudinal outer edge of the dorsal exterior body are aligned, and the absorbent main body has an edge along the longitudinal direction. When viewed from above in a state where they are matched, the entire area of each seal portion is located on the side where the ventral exterior body is located,
When the diaper is cut open along the sealing portion and is expanded to its maximum extent, the length of the ventral exterior body in the width direction and the length of the dorsal exterior body in the width direction are the same. ,
The breaking strength of the ventral exterior body is higher than the breaking strength of the dorsal exterior body,
The back side exterior body has a low basis weight portion extending along the longitudinal direction and a high basis weight portion extending along the longitudinal direction and having a higher basis weight than the low basis weight portion along the width direction. A pants-type disposable diaper comprising sheets alternately formed . When the ventral exterior body and the dorsal exterior body are each extended to the same length along the width direction, the stretching stress along the width direction of the ventral exterior body is The pants-type disposable diaper according to claim 1, wherein the elongation stress is higher than the elongation stress along the width direction of the exterior body. Both the ventral exterior body and the dorsal exterior body include thread-like or band-like elastic members,
By making the elongation magnification of the elastic member in the ventral exterior body higher than the elongation magnification of the elastic member in the dorsal exterior body, the elongation stress along the width direction of the ventral exterior body is The pants-type disposable diaper according to claim 2, which is formed to have a higher elongation stress in the width direction of the side exterior body. Both the ventral exterior body and the dorsal exterior body include thread-like or band-like elastic members,
By making the thickness of the elastic member in the ventral exterior body thicker than the thickness of the elastic member in the dorsal exterior body, the elongation stress along the width direction of the ventral exterior body is applied to the dorsal exterior body. The pants-type disposable diaper according to claim 2 or 3, which is formed to have a higher elongation stress than the extension stress along the width direction of the exterior body. Both the ventral exterior body and the dorsal exterior body include thread-like or band-like elastic members extending in the width direction and arranged in plurality along the longitudinal direction,
By making the interval between the elastic members adjacent in the longitudinal direction in the ventral exterior body larger than the interval between the elastic members adjacent in the longitudinal direction in the dorsal exterior body, the The pants-type disposable diaper according to any one of claims 2 to 4, wherein the elongation stress along the width direction is higher than the elongation stress along the width direction of the back side exterior body. Both the ventral exterior body and the dorsal exterior body include thread-like or band-like elastic members,
By configuring each of the elastic members with resins having different moduli of elasticity, the stretching stress along the width direction of the ventral exterior body is made higher than the stretching stress along the width direction of the dorsal exterior body. The pants-type disposable diaper according to any one of claims 2 to 5, which is formed as a. When considering an imaginary line passing through the longitudinal end of the absorbent body and extending along the width direction, the elongation stress along the width direction of the exterior body located closer to the crotch region than the imaginary line is , the pants type according to any one of claims 1 to 6, wherein the elongation stress along the width direction of the exterior body located closer to the end of the longitudinal direction of the disposable diaper than the imaginary line is higher. disposable diapers. The pants-type disposable diaper according to any one of claims 1 to 7, wherein the thickness of the ventral exterior body is greater than the thickness of the dorsal exterior body in a natural state. The dorsal exterior body is made up of a plurality of elastic members arranged in a non-stretched state so as to extend in one direction without intersecting each other, and joined to a nonwoven fabric that is stretchable over the entire length of the plurality of elastic members. The pants-type disposable diaper according to any one of claims 1 to 8 , comprising an elastic sheet. When the exterior body is stretched in the width direction so as to have the expected waist circumference of the wearer, an elongation stress along the width direction in the ventral exterior body and an elongation along the width direction in the dorsal exterior body. The pants-type disposable diaper according to any one of claims 1 to 9 , wherein the stress is the same.

Images