JP4519025B2 - Pants-type disposable diapers - Google Patents

Description

  The present invention relates to a pants-type disposable diaper.

  Leg holes in pants-type disposable diapers are generally concavely curved. A diaper having a shape in which a front leg hole is bored inward with respect to such a leg hole is known (see, for example, Patent Documents 1 and 2). In these diapers, the purpose of making the leg hole in such a shape is not to fit the leg hole to the wearer's buttocks. Therefore, it cannot be said that the shape of the leg hole is optimized for the wearer's body. Therefore, when an elastic member is disposed in the leg hole in order to prevent a gap from being generated around the wearer's leg, excessive tightening is likely to occur. Moreover, it is easy to shift | deviate due to operation | movement, and it cannot be said that the external appearance in a diaper wearing state is favorable.

  Moreover, what has arrange | positioned the elastic member extended in the width direction of a diaper as a underpants type disposable diaper between the waist opening part and the leg opening part is known. For example, at least the ventral side of the diaper is defined between a first waist region defined by a maximum of 20 mm in each of the upper and lower sides with the front end edge of the core as a boundary, and between the first waist region and the leg opening. A pants-type disposable diaper having a second waistline area, wherein the arrangement interval dimension of the elastic members in the first waistline area is smaller than the arrangement interval dimension of the elastic members in the second waistline area. It has been proposed (see Patent Document 3). In this diaper, the first torso area is more than the second torso area in terms of adhesion to the skin while substantially equalizing the surface pressure per fixed area in the first torso area and the second torso area. By making it good, it is intended to prevent leakage without impairing the feeling of wearing the diaper. Also known is a pants-type disposable diaper that has a strong contraction force acting on the upper part of the wearer's torso and lumbar bone by gradually reducing the spacing between the elastic members toward the leg opening. (See Patent Document 4). However, in these diapers, the diaper is easily slipped off while the diaper is worn, and the appearance of the diaper is not good. Although it is conceivable to increase the tightening pressure at the waist opening to prevent slippage, in that case, it may be difficult to wear a diaper.

  In addition, as a pants-type disposable diaper, a diaper in which the leg periphery cut position of the outer sheet forming the leg opening in the diaper crotch minimum width portion is positioned more centrally than the outer edge of the absorbent body 5 mm Is described (see Patent Document 5). However, in this diaper, the appearance of the undercarriage when worn is clean, but the diaper tends to slip during wearing, so the appearance after wearer activity is not good.

JP-A-9-66071 Japanese National Patent Publication No. 11-506653 Japanese Patent Laid-Open No. 9-84826 Japanese Utility Model Publication No. 6-421 JP 2002-159528 A

  Accordingly, it is an object of the present invention to provide a pants-type disposable diaper that can eliminate the various drawbacks of the above-described prior art.

  The present invention comprises an absorbent main body having an absorbent core, and an outer packaging material that is positioned on the non-skin-contacting surface side of the absorbent main body and fixes the absorbent main body. A pants-type disposable diaper in which a leg opening is formed, wherein the absorbent core includes a hydrophilic long fiber web, and the long fiber has a crimp rate of 40 to 90%. The elastic core is oriented in the planar direction of the absorbent core, and elastic members along the peripheral shape of the leg opening are not arranged on both sides of the outer packaging material in the crotch part of the diaper, and the diaper is placed directly beside it. When the virtual development view obtained by virtually cutting and developing in the vertical direction at the position of is considered, at the front side, the angle formed by the virtual vertical cutting line and the leg hole intersecting this is less than 90 degrees Yes, at the rear side, the position P1 of the lower end of the virtual vertical cutting line, In addition, the leg hole has a convex shape outwardly from the straight line P1-P2 that connects the position P2 of the intersection of the longitudinal center line and the leg hole. The position on the straight line P1-P2 at which the distance from the hole is the largest is closer to the center of the virtual development view than the midpoint of the straight line P1-P2, and the distance between the position and the midpoint is 0 to 50 mm. The length T1 from the lower end portion of the virtual vertical cutting line in the front side portion to the minimum width portion in the virtual development view and the lower end portion of the virtual vertical cutting line in the rear side portion to the minimum width portion in the virtual development drawing Ratio of length T2 of T1, T1: T2 is 25: 75-40: 60, and wearing a region that comes into contact with the site from the wearer's iliac crest to upper anterior iliac spine when wearing a diaper The pressure is higher than the wearing pressure at the waist opening It is obtained by achieving the above object by providing a shorts type disposable diaper that is adapted.

In the pants-type disposable diaper of the present invention, the crotch part of the diaper closely follows the wearer's buttocks, and the crotch part of the diaper is clean in appearance. Moreover, the clamping force by a leg hole can be reduced. In addition, it is difficult for the diaper to fall off due to the movement of the wearer during wearing of the diaper, and to expose the buttocks due to the rear side of the leg hole being raised. In particular, bumping of the crotch of the diaper is difficult to occur. Due to the fact that the excessive tightening force of the leg holes can be reduced, and that the diaper is less likely to slip or rise, the wearer's movement is less likely to be hindered.
In addition, the outer wrapping material at the crotch of the diaper is less likely to form frills and flared parts around the legs, and the appearance around the legs is much cleaner. The part can also prevent the wearer from feeling uncomfortable.
Furthermore, since it is possible to reduce the thickness and the basis weight while maintaining the same absorption capacity as that of the conventional absorbent body, the overall view of the attachment is clear and the crotch portion is not particularly sticky. It is also thin and convenient for carrying. Moreover, since the structure of the absorber is not destroyed even if the wearer performs violent movements, the absorbency is maintained without twisting, and the pad stability is also good.

  The present invention will be described below based on preferred embodiments with reference to the drawings. The perspective view of one Embodiment of the underpants type disposable diaper of this invention is shown by FIG. FIG. 2 is an exploded perspective view showing a state before the diaper shown in FIG. 1 is assembled. FIGS. 3A and 3B are plan views of the outer packaging material in FIG. 2 in a developed state. 3 (a) and 3 (b) are the same drawing, and the reference numerals are divided for the purpose of making the drawing easy to see. In the following description, a virtual development view refers to a figure obtained by virtually cutting and developing a pants-type diaper in the vertical direction at a position just beside it. Moreover, a virtual vertical cutting line means a line when virtually cutting a pants-type diaper in a vertical direction at a position just beside the diaper.

  The diaper 1 of the present embodiment has a liquid-permeable top sheet 2, a liquid-impermeable or water-repellent back sheet 3, and a liquid-retaining absorbent core 4 interposed between both sheets 2 and 3. In particular, a vertically long absorbent body 10 and an outer packaging material 11 disposed on the back sheet 3 side of the absorbent body 10 are provided.

  The outer packaging material 11 has an hourglass shape in which both side edges are bound inward in the central portion in the longitudinal direction, and defines the outline of the diaper. As a result, leg holes H are formed on the left and right sides of the outer packaging material 11 (see FIG. 2). The outer packaging material 11 is divided in the longitudinal direction into an abdominal side A disposed on the wearer's abdominal side, a back side B disposed on the back side, and a crotch C positioned therebetween. The ventral side A, the back side B, and the crotch C are arranged in the longitudinal direction (in FIG. 3) of the diaper 1 in the unfolded state (the state in which the elastic member of each part is expanded and expanded in a flat shape, as shown in FIG. Each region is divided into three regions so that the total length in the vertical direction is divided into approximately three equal parts. As shown to Fig.3 (a), the flap part F extended in the left-right direction is formed in the longitudinal direction front side part and rear side part of the outer packaging material 11, respectively. In the outer packaging material 11, both side edges A1, A2 of the flap part F on the ventral side A and both side edges B1, B2 of the flap part F on the back side B are joined to each other, as shown in FIG. The diaper 1 is formed with a waist opening 5 and a pair of leg openings 6. Moreover, a pair of side seal part S is formed in the right-and-left both-sides edge of the diaper 1 by this joining. For this joining, for example, heat sealing, high frequency sealing, ultrasonic sealing or the like is used. In addition, in the diaper 1 of this embodiment, since the side seal part S is provided beside the diaper 1, the virtual obtained by virtually cutting the diaper 1 vertically in the position next to the diaper 1 and developing it. The shape of the developed view matches the shape of the developed view of the outer packaging material 11. The virtual vertical cutting line coincides with the line passing through the side seal portion S in the vertical direction.

  Each of the top sheet 2 and the back sheet 3 has a rectangular shape, and these and the absorbent core 4 are integrated to form a vertically long absorbent body 10. As the surface sheet 2 and the back surface sheet 3, the same material as that conventionally used for this type of diaper can be used. Details of the absorbent core 4 will be described later.

  As shown in FIG. 2, side cuffs 8, 8 made of a liquid-resistant or water-repellent and breathable material are formed on the left and right sides of the absorbent body 10 in the longitudinal direction. Each side cuff 8 has a fixed end and a free end along the longitudinal direction of the absorbent body 10. The fixed end is fixed to the top sheet 2. On the other hand, a side cuff elastic member 81 is arranged in an expanded state in the vicinity of the free end. Thereby, the side cuff 8 stands up and the outflow of the liquid to the width direction of the absorber main body 10 is prevented.

  The outer packaging material 11 has at least two nonwoven fabrics, that is, an outer layer nonwoven fabric 12 and an inner layer nonwoven fabric 13 disposed on the inner surface side of the outer layer nonwoven fabric 12. The outer layer nonwoven fabric 12 forms the outer surface of the diaper 1, and the inner layer nonwoven fabric 13 is joined to the inner surface side of the outer layer nonwoven fabric 12 with an adhesive such as a hot melt pressure-sensitive adhesive. It is preferable that the outer layer nonwoven fabric 12 and the inner layer nonwoven fabric 13 are water-repellent while taking into consideration the liquid oozing property.

  The outer packaging material 11 extends outward from the front and rear end edges of the absorbent body 10, and the extended portion is folded back to the absorbent body 10 side. The wrapped outer packaging material 11 covers the front and rear end portions of the absorber body 10 (that is, the top sheet 2 at the front and rear end portions of the absorber body 10).

  As shown in FIG. 3 (b), a plurality of waist elastic members 51, 51 are disposed along the width direction of the front and rear end portions of the outer packaging material 11 along the front and rear end edges. The waist elastic members 51 and 51 are sandwiched and fixed in an expanded state by the outer layer nonwoven fabric 12 and the inner layer nonwoven fabric 13. The waist elastic members 51, 51 are formed on the elastic members 51, 51 when the side edges A1, A2 of the ventral side A of the diaper 1 and the side edges B1, B2 of the back side B are joined to each other. It arrange | positions so that edge parts may overlap. As a result, as shown in FIG. 1, a substantially continuous ring-shaped waist gather is formed in the vicinity of the waist opening 5 of the diaper 1.

As shown in FIG. 3B, elastic members along the peripheral shape of the leg opening are not arranged on both sides of the outer packaging material 11 in the diaper crotch C. That is, in a conventional pants-type disposable diaper comprising an absorbent main body and an outer packaging material, legs are formed so as to be substantially continuous from the diaper belly side portion to the back side portion on the left and right curved portions of the outer packaging material 11. It is common to form a substantially continuous ring-shaped leg gather in the vicinity of the leg openings 6 and 6 of the diaper 1 by contraction of the leg elastic member. . However, leg gathers formed by an elastic member disposed on the outer packaging material are not preferable in that they form a frilled or flared portion around the leg, and the appearance around the leg is clean. Such gathers also give the wearer an uncomfortable feeling when pants or the like are put on the diaper.
In the present diaper 1, by not arranging elastic members along the peripheral shape of the leg opening on both sides of the outer packaging material 11 in the diaper crotch C, the appearance around the legs can be made even cleaner, Also, it is possible to prevent a sense of incongruity when pants or the like are worn on top of each other.

  In the diaper 1, a large number of elastic members extending in the width direction of the diaper 1 are arranged between the waist opening 5 and the leg opening 6 in the stomach side A and the back side B of the diaper 1. By arranging the elastic member, as shown in FIG. 3B, a first region 71 and a second region extending in the width direction of the diaper 1 between the waist opening 5 and the leg opening 6. 72 is formed. A first elastic member 71 a is disposed in the first region 71, and a second elastic member 72 a is disposed in the second region 72. The first region 71 is located between the waist opening 5 and the leg opening 6, and the second region 72 is located between the first region 71 and the leg opening.

  Both the first elastic member 71a and the second elastic member 72a are sandwiched and fixed between the outer nonwoven fabric 12 and the inner nonwoven fabric 13 in an expanded state. The first elastic member 71a is a first elastic member 71a of the ventral side A when the side edges A1, A2 of the ventral side A of the diaper 1 and the side edges B1, B2 of the back side B are joined together. And the first elastic member 71a of the back side portion B are arranged so as to overlap each other. The same applies to the second elastic member 72a. As a result, as shown in FIG. 1, gathers are formed in the first region 71 and the second region 72 in the ventral side A and the back side (not shown) of the diaper 1, respectively.

  Both the first elastic member 71 a and the second elastic member 72 a extend between the left and right side edges of the diaper 1 (that is, the left and right side edges of the outer packaging material 11) and the left and right side edges of the absorbent core 4. Yes. And in the site | part in which the absorptive core 4 exists, neither the 1st elastic member 71a and the 2nd elastic member 72a exist substantially. As a result, the gathers formed in the first region 71 and the second region 72 are located between the left and right side edges of the diaper 1 and the left and right side edges of the absorbent core 4, and the absorbent core 4 is present. The position is substantially free of gathers.

  As each elastic member in the diaper 1 of the present embodiment, a stretchable material such as natural rubber, polyurethane resin, urethane foam resin, stretchable nonwoven fabric or hot melt stretchable member is used as a thread (thread rubber) or a strip (flat). (Rubber), net (net) or film is preferably used.

  As shown in FIG. 3 (a), in the diaper 1 of the present embodiment, the virtual longitudinal section line in the virtual development view described above, that is, in the front side portion of the development view of the outer packaging material 11 in the diaper 1 of the present embodiment. That is, the angle θ1 formed by the vertical line S1 passing over the side seal portion and the leg hole intersecting with the vertical line S1 is less than 90 degrees. That is, the shape of the leg hole in the abdominal side A of the diaper 1 (the front side in the developed view of the outer packaging material 11) is a concave shape that is hollowed inward. This angle is preferably 50 to 85 degrees. On the other hand, in the rear side portion of the developed view of the outer packaging material 11, a straight line P1 connecting the position P1 of the lower end portion of the vertical line S2 passing over the side seal portion and the position P2 of the intersection of the longitudinal center line U and the leg hole. The leg hole has a convex shape outwardly than -P2.

  As described above, in the diaper 1 of the present embodiment, the leg hole on the ventral side A has a concave shape that is recessed inward, and the leg hole on the rear side of the development view is convex outward. It has a shape. Such a uniquely shaped leghole fits very well into the wearer's buttocks. As a result, the appearance of the diaper 1 in a worn state is extremely good. In particular, the crotch part C of the diaper 1 is clean in appearance. Moreover, since a gap is prevented from being generated around the wearer's legs, when an elastic member is disposed in the leg hole of the diaper 1, the tightening force can be reduced. In addition, it is difficult for the diaper 1 to fall off due to the wearer's movement or the like while the diaper 1 is worn, and to expose the buttock due to the rear side of the leg hole. In particular, bumping of the crotch part C of the diaper 1 is difficult to occur. Due to the fact that the tightening force of the leg hole of the diaper 1 can be reduced and it is difficult for slipping off or slipping up, the wearer's operation is hardly hindered.

  In addition, the leg hole of the rear side part of the developed view has a convex shape facing outward means that not only the shape shown in FIG. This includes a shape having a part, for example, the shape shown in FIGS.

  From the viewpoint of better fitting the leg hole to the wearer's buttocks, on the rear side of the development of the outer packaging material 11, as shown in FIG. The position on the straight line P1-P2 (indicated by P3 in the figure) at which the distance from the largest is developed more than the midpoint of the straight line P1-P2 (indicated by P4 in the figure). It is located at the center of the figure. That is, when the apex of the leg hole having a convex shape is located near the crotch C of the diaper, the leg hole can be fitted to the wearer's buttocks better.

  Similarly, from the viewpoint of better fitting the leg hole to the wearer's buttocks, as shown in FIG. 3 (a), the straight line where the distance between the straight line P1-P2 and the leg hole in the convex portion is the largest. The distance between the position P3 on P1-P2 and the midpoint P4 of the straight line P1-P2 is set to 0 to 50 mm. This distance is preferably 0 to 30 mm, particularly preferably 0 to 20 mm.

  In order to fit the leg hole well to the wearer's buttocks, the balance between the ventral side A and the back side B of the diaper 1 is also important. Specifically, as shown in FIG. 3 (a), the length T1 from the lower end of the vertical line S1 passing over the side seal portion in the front side portion of the development view of the outer packaging material 11 to the minimum width portion in the development view. And the ratio of the length T2 from the lower end portion of the vertical line S2 passing over the side seal portion on the rear side portion of the developed view of the outer packaging material 11 to the minimum width portion in the developed view, that is, T1: T2 is 25: It is set to 75-40: 60. This ratio is preferably T1: T2 = 30: 70 to 35:65. If the ratio of T1 and T2 is outside this range, the leg hole will not fit in the buttock so as to follow the three-dimensional shape of the buttock, and a gap will be prevented between the diaper and the wearer's body. Therefore, it is necessary to dispose an elastic member having an excessive tightening force on the diaper, and the appearance of the diaper in a worn state is deteriorated. When the minimum width portion is not fixed at one place and the minimum width portion has the same width and extends in the longitudinal direction, the position of the same width portion in the longitudinal direction is defined as the minimum width portion.

  In order for the position of the leg hole to properly fit the wearer's buttocks even when the wearer moves, the peripheral portion of the leg hole is located on the rear side of the developed view of the outer packaging material 11. The present inventors have found that it is advantageous to be able to expand and contract in a direction orthogonal to the above. For this purpose, as shown in FIG. 3 (a), an elastic member E is arranged between the outer nonwoven fabric and the inner nonwoven fabric at the peripheral edge of the leg hole on the rear side portion to impart stretchability to the part. It is preferable to do. In this case, the direction in which the elastic members E are arranged is such that the angle θ2 formed with the center line V in the width direction in the developed view of the outer packaging material 11 is preferably 10 to 90 degrees, more preferably 30 to 60 degrees. . As a result, even if the wearer moves, the part flexibly expands and contracts following the expansion and contraction of the skin caused by the movement of the legs, thus preventing bumping of the part and exposure of the buttocks due to the shift of the part be able to. As a result, the wearing feeling and appearance of the diaper 1 in the worn state are further improved.

  From the viewpoint of further improving the appearance of the diaper in the worn state, as shown in FIG. 3 (a), in the expanded state of the outer packaging material 11, the lower end of the vertical line S1 passing over the side seal part in the front side part, and the rear It is preferable that the distance M between the lower end portion of the vertical line S2 passing on the side seal portion in the side portion is 210 to 280 mm (hereinafter, this distance is referred to as a lower end distance). The value of the distance M between the lower ends is a value optimized for the wearer's body shape, and is characterized by a value shorter than the distance between the lower ends in the conventional pants-type diaper. The distance M between the lower ends is a scale representing the length or area of the portion located in the crotch portion of the wearer in the pants-type diaper. Specifically, in a pant-type diaper having a long distance between the lower ends M, the length of the portion located in the crotch portion of the wearer is long or the area is widened, and in a diaper having a short distance between the lower ends M, the opposite is true. And in the diaper 1 of this embodiment, as a result of optimizing the distance M between lower ends with respect to a wearer's body shape, it shortens compared with the conventional underpants type diaper. The length of the located part is shorter than before, or the area is narrower than before. As a result, the portion of the absorbent core 4 of the diaper 1 that is present in the crotch portion of the wearer is reduced, and the crotch portion C of the diaper 1 is less prone to appear and the appearance is neat. For this reason, the wearer's movement, particularly the movement of the foot, is hardly disturbed. Moreover, it is difficult for the diaper to fall off due to the movement of the wearer while wearing the diaper. As a result, it is difficult for urine and feces to leak. In addition, when putting over pants or trousers on the diaper, it is easy to wear, and the appearance after rinsing is clean.

  From the viewpoint of making the appearance of the crotch part C of the diaper 1 clearer, the distance M between the lower ends of the diaper 1 is preferably 230 to 270 mm, particularly preferably 230 to 260 mm.

  In order to improve the appearance of the diaper crotch C by having an appropriate amount (length or area) of the absorbent core 4 in the crotch of the wearer, not only the distance M between the lower ends but also the diaper crotch C The dimension in the width direction is also important. If the size of the diaper crotch part C is too large, the crotch part C will not fit properly to the wearer's crotch part, resulting in looseness. From this point of view, in the present embodiment, the width of the minimum width portion of the diaper crotch lower portion C, that is, the width N of the minimum width portion in the center portion in the longitudinal direction of the unwrapped outer packaging material 11 (see FIG. 3A) is 50. It is preferable to set to ~ 150 mm.

  The width N of the minimum width portion is shorter than that of a conventional pants-type diaper. That is, in the diaper 1 of this embodiment, the dimension of the absorptive core 4 which exists in a wearer's crotch part becomes short compared with the conventional pants type diaper in any of the longitudinal direction and the width direction. Yes. From the viewpoint of further improving the appearance of the diaper crotch portion C, the width N of the minimum width portion is preferably 60 to 140 mm, particularly preferably 60 to 120 mm.

  In the diaper 1 of the present embodiment, the pressure when the diaper 1 is worn in the first region 71 described above is preferably 1.1 to 2.5 kPa, more preferably 1.1 to 2.0 kPa, and even more preferably. By setting it as 1.2-1.8 kPa, the fall of the diaper 1 can be prevented and the external appearance of the diaper 1 in a wearing condition can be further improved. The first region 71 is preferably formed at a portion that abuts a portion (hereinafter also referred to as an iliac region) from the wearer's iliac crest to the upper anterior iliac spine when the diaper 1 is worn. The iliac crest and superior anterior iliac spine are anatomical terms. The iliac crest is a part indicated by 9a in FIG. 7, and the superior anterior iliac spine is a part indicated by 9b in FIG. Conventionally, in order to prevent slipping while wearing a pants-type diaper, particularly to prevent slipping while wearing a pants-type disposable diaper for infants, tightening an elastic member disposed in the waist opening It has been considered effective to increase the pressure so that the pants-type diaper is in close contact with the wearer's body through the waist opening. However, as a result of the study by the present inventors, in order to effectively prevent slippage during wearing of the pants-type diaper, it corresponds to the wearer's iliac region rather than increasing the tightening pressure of the waist opening. It has been found that it is effective to increase the tightening pressure of the diaper part as compared with the prior art. The reason for this is that wearers, particularly infants, have their waists protruding as a physical feature, so if the tightening pressure of the waist opening that abuts the protruding belly is increased, the tightening pressure is high. This is because the waist opening is gradually narrowed down and the waist opening is shifted down to a site where the abdomen becomes thinner.

  The pressure when the diaper 1 is worn in the first region 71 can be controlled by adjusting, for example, the material, thickness, elongation rate, or arrangement interval of the first elastic member 71a.

  The pressure at the time of wearing the diaper 1 in the first region 71 is that the diaper 1 is mounted on a cylinder having a circumference of 500 mm, and the mounting pressure measuring device (contact pressure measuring device (AMI3037-2 manufactured by AIM Techno Co., Ltd.)). Measured by. The specific measurement method is as follows.

[Method for Measuring Pressure in First Region 71]
Using an air pack of φ = 15 mm, set the air pack so that the center of the air pack is positioned at the tip of the waist opening, and measure the mounting pressure (P1). The position of the diaper width direction in which the air pack is set is approximately the center between the left and right side edges of the diaper and the left and right side edges of the absorbent core 4. Subsequently, the center of the 5 mm air pack is moved in the length direction of the diaper 1 to measure the mounting pressure (P2). Similarly, measurement is performed at intervals of 5 mm to obtain P3, P4, P5,. The measurement of P1 to Pn is performed over a range where the left and right side portions of the outer packaging material 11 from the waist opening to the leg opening are joined to each other. For P1 to Pn, a total of four points are measured on the ventral side, two on each side. These average values are taken as the pressure on the ventral region. Similarly, a total of four points are measured on the back side, and the average value is set as the mounting pressure on the back side. The distance between the portions corresponding to 1.1 to 2.5 kPa continuously in the values of P1 to Pn is defined as the width of the first region 71. For example, when P3 to P6 are applicable, the width of the region = (6-3) × 5 = 15 mm. The center of the first region 71 at that time is the midpoint between the measurement point 3 and the measurement point 6.

  The reason why the circumference of the cylinder is set to 500 mm is that the average length around the belly of an infant who is a main subject wearing the diaper 1 of the present embodiment is approximately 500 mm. The length of the abdomen around here is an average value of the abdomen circumference measured in the standing position and the sitting position in consideration of the change in the circumference of the abdomen when the posture of the infant changes.

  The part from the wearer's iliac crest to the upper anterior iliac spine has a certain width, and the first region 71 of the diaper 1 is fixed to the part within the range of the width. Can be effectively prevented. From this viewpoint, in the diaper 1 of the present embodiment, as shown in FIG. 3B, the width of the first region 71 (that is, the length of the first region 71 along the longitudinal direction of the diaper 1) is set to 12. It is preferable to set it to -35 mm. When the width W is 20 to 35 mm, particularly 25 to 30 mm, the diaper 1 can be prevented from slipping off more effectively, and the appearance of the diaper 1 in the wearing state and the wearing operation of the diaper 1 (easy to use) Etc.) can be further improved.

  In a state where the diaper 1 is worn, the relationship between the dimensions of the diaper 1 and the physique of the wearer in order for the first region 71 to abut on the site from the wearer's iliac crest to the superior anterior iliac spine. It is also important. For example, when an infant who is a main wear target person of a pants-type diaper is considered, in the unfolded state of the diaper 1, the center position of the first region 71 of the ventral side A (center position along the longitudinal direction of the diaper 1) and the diaper 1. And the center position of the first region 71 of the back side portion B (the center position along the longitudinal direction of the diaper 1) in a deployed state of the diaper 1 with a distance K1 between the longitudinal center line CL of the diaper 1 and 180 mm By setting the distance K2 between the diaper 1 and the longitudinal center line CL to 180 to 230 mm, the first region 71 can be successfully brought into contact with the wearer's iliac region. This value is determined by carrying out body measurements of about 350 infants who are the main wearees of pants diapers. Specifically, as shown in FIG. 8, the abdominal side left and right center point at the horizontal position height of the upper anterior iliac spine is the upper anterior iliac spine height front center, and the dorsal side is the upper anterior iliac spine height. As the posterior center, the length from the center of the superior anterior iliac spine to the center of the posterior center of the superior anterior iliac spine via the crotch is defined as the longitudinal length of the superior anterior iliac spine. The numerical value obtained by adding the necessary length in consideration of the thickness of the diaper material is divided into two. By setting the distances K1 and K2 to 185 to 220 mm, particularly 195 to 215 mm, the first region 71 can be brought into more successful contact with the wearer's iliac region.

  It is preferable to mainly use the first elastic member 71 a disposed in the first region 71 for the tightening force in the diaper 1 of the present embodiment. In other words, unlike the conventional pants-type diaper, it is not necessary to use the tightening force by the elastic member arranged in the waist opening 5 as a main means for fixing the diaper 1 to the wearer's body. On the contrary, it has been confirmed by the present inventors that if the tightening force of the waist opening 5 is increased, the diaper 1 is displaced. From this viewpoint, in the diaper 1 of the present embodiment, it is preferable that the pressure of the waist opening 5 at the time of wearing the diaper is 0.3 to 1.2 kPa, which is a lower value than that of the conventional pants-type diaper. . This pressure is preferably lower than the pressure in the first region 71 when the diaper is worn. Moreover, by setting the pressure of the waist opening 5 at the time of wearing the diaper within the above range, there is an advantage that the waist opening 5 can be easily expanded when the diaper 1 is worn, and the wearing operation can be easily performed. If it is less than 0.3 kPa, the natural length of the diaper 1 before wearing is increased, which may cause problems such as poor appearance when viewed as clothes.

  When the pressure of the waist opening 5 when wearing a diaper is more preferably 0.4 to 1.2 kPa, more preferably 0.4 to 0.8 kPa, the diaper 1 can be prevented from slipping off more effectively. can do. The pressure of the waist opening 5 can be measured by the same method as the pressure of the first region 71 described above. That is, a cylinder having a circumferential length of 500 mm is inserted (attached) into the waist opening 5 of the diaper 1, and the center of the air pack of the attachment pressure measuring device is located at a position 15 mm in the diaper longitudinal direction from the front end of the waist opening. Measure the pressure. The measurement is performed at 10 points at intervals of 50 mm in the circumferential direction, and the average value is taken as the pressure at the waist opening. As shown in FIGS. 9A and 9B, both side edges A1, A2 of the ventral side A are not joined to both side edges B1 ′, B2 ′ of the back side B, and both side edges B1 ′, In the case of being joined at B1 and B2 which are positions inward in the longitudinal direction from B2 ′, the waist opening is the position closest to the end in the region where the abdomen and the back overlap. . The pressure of the waist opening 5 can be controlled, for example, by adjusting the material, thickness, elongation rate, or arrangement interval of the waist elastic member 51. When the pressure of the waist opening 5 falls within the pressure range of the first region 71, the position is included in the first region 71.

Furthermore, in the diaper 1 of this embodiment, the pressure of the 2nd area | region 72 located between the 1st area | region 71 and the leg opening part 6 at the time of diaper wear is preferably 0.2-0.8 kPa, More preferably It is made 0.3-0.6 kPa. As a result, the diaper 1 can be brought into close contact with the wearer's body with an appropriate pressure, and liquid leakage can be effectively prevented. When the diaper 1 is worn, the second region 72 contacts the lower region (lower abdomen) of the wearer's iliac region. As shown in FIG.3 (b), it is preferable that the width | variety (namely, the length of the 2nd area | region 72 along the longitudinal direction of the diaper 1) W2 of the 2nd area | region 72 is 40-70 mm, especially 45-65 mm.

  As shown in FIG. 8, the absorbent core 4 in the present diaper 1 includes a central absorbent body 4b and a pair of side absorbent bodies 4a and 4c located on both sides of the central absorbent body 4b in the crotch part C of the diaper. It is separated. In the crotch part C of the diaper, each absorber 4a, 4b, 4c extends in the longitudinal direction. These three absorbent bodies are entirely wrapped with a tissue paper (not shown) to constitute an integral absorbent core 4. The left and right side absorbent bodies 4 a and 4 c are continuous with the central absorbent body 4 b at both ends in the longitudinal direction of the absorbent core 4. The lower surface of the absorbent core 4 is bonded and fixed to an outer packaging material (not shown) or the back sheet 3 fixed thereto. In this case, the side absorbent bodies 4a and 4c are provided inside the absorbent main body 10. The arranged portion is not fixed to the outer packaging material, and can be separated from the outer packaging material. On the other hand, the portion of the absorbent main body 10 in which the central absorbent body 4 b is disposed is fixed to the outer packaging material 11. Due to such a configuration, while the diaper is worn, the side absorbent bodies 4a and 4c are arranged inside the absorbent main body 10 by the body pressure applied in the width direction of the absorbent core 4. The part (side part of the absorbent main body) rises away from the outer packaging material. An elastic member is disposed in the vicinity of the outer edge of each of the pair of side absorbent bodies 4a and 4c (the edge on the outer side in the width direction of the absorbent core 4) for the purpose of improving the rising property of the side part of the absorbent main body. It is preferable that As a result, the substantial width of the absorbent core 4 approaches the width of the central absorbent body 4b. In short, although the width of the absorbent core 4 before wearing the diaper is large, the width of the absorbent core 4 during wearing becomes small, and the absorbent core 4 comes to fit the wearer's crotch appropriately. At the same time, the absorption capacity of the absorbent core 4 as a whole is sufficiently ensured by the presence of the side absorbers 4a and 4c. For these reasons, in the diaper of the present embodiment, even if the amount of the absorbent core 4 present in the crotch portion of the wearer is reduced, a decrease in the absorption capacity is prevented.

  Furthermore, by separating the absorbent core 4 in the crotch part C of the diaper into the central absorbent body 4b and the side absorbent bodies 4a and 4c, both sides of the absorbent core 4 and the absorbent main body 10 are twisted at the crotch part. It becomes easy to fit well to the wearer's buttocks without bending or leaving the skin. As a result, the appearance around the wearer's leg can be further improved, and the feeling of tingling can be further reduced when overpants or trousers are stacked. In addition, 20-90 mm is preferable, as for the width | variety of the center absorber measured on the said line CL, it is still more preferable that it is 20-80 mm, and it is still more preferable that it is 30-70 mm. Moreover, it is preferable that the width | variety (width before the right-and-left division body separates) of the absorptive core 4 before mounting | wearing of the diaper 1 is set to 50-150 mm. From the viewpoint of absorption performance in the crotch, it is more preferably 60 to 150 mm, and further preferably 70 to 140 mm.

In the present diaper 1, the absorbent core 4 includes a web of hydrophilic long fibers having a crimp rate of 40 to 90% and oriented in the plane direction of the absorbent core. Use what you have. Hereinafter, the absorbent core having this configuration is also referred to as a long fiber absorbent core.
By using a long fiber absorbent core, it is possible to reduce the thickness and basis weight while maintaining the same absorption capacity as a conventional absorbent body. There's nothing going on. It is also thin and convenient for carrying. Moreover, since the structure of the absorber is not destroyed even if the wearer performs violent movements, the absorbency is maintained without twisting, and the pad stability is also good.

Hereinafter, examples of the long fiber absorbent core preferably used in the present invention will be described.
FIG. 9 is a schematic cross-sectional view showing an example of the long fiber absorbent core. A long fiber absorbent core 101 shown in FIG. 9 mainly includes a long fiber web (hereinafter referred to as web) 102 and a superabsorbent polymer spray layer (hereinafter referred to as polymer layer) 103. The long fiber absorbent core 101 includes a plurality of webs 102, and a polymer layer 103 is located between the webs 102 and 102. The number of web layers may be three or more.

  The long fibers having hydrophilicity are inherently hydrophilic long fibers, and are inherently non-hydrophilic, but are provided with hydrophilicity by being subjected to a hydrophilic treatment. Both are included. Preferred long fibers are inherently hydrophilic long fibers, and particularly preferred are acetate and rayon long fibers. In particular, acetate is particularly preferable because it retains bulkiness even when wet.

As the long fiber, a crimped one is used. The long fiber has a crimp rate (JIS L0208) of 40 to 90%, preferably 50 to 80%. By forming a web from crimped long fibers, it becomes easy to stably and highly embed a superabsorbent polymer in the web. If the web is composed only of long fibers that do not have crimps or have a small degree of crimp, and this is used as an absorbent body, when a large amount of superabsorbent polymer is used, its extreme movement and dropout may occur. It is easy to happen. On the other hand, if long fibers with a too high crimp rate are used, it is not easy to allow the superabsorbent polymer to enter between the long fibers. It is easy to happen. There is no particular limitation on the means for crimping the long fibers. Further, the crimp may be two-dimensional or three-dimensional. The crimp rate is defined as a percentage of the difference between the length A when the long fiber is stretched and the length B of the original long fiber with respect to the length A when stretched, and is calculated from the following equation: .
Crimp rate = (A−B) / A × 100 (%)

  The length of the original long fiber means a length in which both ends of the long fiber are connected with a straight line when the long fiber is in a natural state. The natural state means a state in which one end of the long fiber is fixed to a horizontal plate and hung downward by its own weight. The length when the long fiber is stretched refers to the length at the minimum load when the long fiber is stretched until there is no crimp. The crimp rate of the long fibers is as described above, and the number of crimps is preferably 2 to 25, particularly 4 to 20, especially 10 to 20 per cm.

  The buried support refers to a state in which the superabsorbent polymer enters the space formed by the crimped long fibers, and the polymer is not easily moved or dropped even by vigorous movement of the wearer. . At this time, the long fibers are entangled or caught in the superabsorbent polymer, or the superabsorbent polymer is attached to the long fiber due to its own stickiness. The space formed by the long fiber is easily deformed even when stress is applied from the outside, and the entire long fiber can absorb the stress, thereby preventing the space from being destroyed. A part of the superabsorbent polymer is embedded and supported in the web 102. Depending on the manufacturing conditions of the long fiber absorbent core 101, almost all of the superabsorbent polymer may be uniformly embedded in the web 102.

  There is no restriction | limiting in particular in the fiber diameter of a long fiber. In general, it is preferable to use a long fiber of 1.0 to 7.8 dtex, particularly 1.7 to 5.6 dtex. The long fiber in the long fiber absorptive core is a fiber having a fiber length of preferably 70 mm or more, more preferably 80 mm or more, and even more preferably 100 mm or more when the fiber length is measured by the average fiber length measurement method (Method C) of JIS L1015. I mean. However, when the total length of the web to be measured is less than 100 mm, preferably 50% or more, more preferably 70% or more, more preferably 80% or more of the fibers in the web extend over the entire length of the web. In this case, it is assumed that the fibers of the web are long fibers. The long fibers in the long fiber absorbent core are generally called continuous filaments. A bundle of continuous filaments oriented in one direction is generally called a tow. Therefore, the long fiber in the long fiber absorptive core is a concept including continuous filaments. The web in which long fibers are oriented is a concept including a tow layer of continuous filaments.

  As the superabsorbent polymer embedded and supported in the web, particles are generally used, but fibers may be used. When a particulate superabsorbent polymer is used, if the shape is an irregular type, a block type, or a bowl type, it can be embedded and supported at a basis weight of the same amount to 10 times the web. it can. Further, in the case of a spherical particle aggregation type or a spherical type, it can be embedded and supported with a basis weight of the same amount or more and 5 times or less with respect to the web. For these particle shapes, it is desirable to select the former when it is particularly desired to achieve both high absorption and thinning, and the latter when importance is placed on the texture (reduction of the feeling of shaving of the superabsorbent polymer). The superabsorbent polymer is dispersed in layers between the webs 102 and 2. A part of the superabsorbent polymer is embedded and supported in the web 102. Depending on the manufacturing conditions of the long fiber absorbent core 101, almost all of the superabsorbent polymer may be uniformly embedded in the web 102. “Uniform” means that when the superabsorbent polymer is completely uniformly arranged in the thickness direction or the width direction of the long fiber absorbent core 101 and when a part of the long fiber absorbent core 101 is taken out. The case where the variation in the abundance of the superabsorbent polymer has a distribution within twice the basis weight. Such variation is caused by the fact that, in the production of disposable diapers, the superabsorbent polymer is rarely supplied excessively, and a part with an extremely high application amount is partially generated. In other words, the “uniform” includes cases where inevitably variations occur, and does not include cases where the superabsorbent polymer is distributed so as to intentionally vary.

  As described above, since the long fiber has crimps, it has a large number of spaces capable of holding particles. The superabsorbent polymer is retained in the space. As a result, even if a large amount of superabsorbent polymer is sprayed, the extreme movement or dropout is less likely to occur. Moreover, even if a wearer performs intense operation | movement, the structure of the long fiber absorptive core 101 becomes difficult to be destroyed. Depending on the superabsorbent polymer used, the crimp rate and the amount of long fibers used are adjusted as appropriate. The long fiber absorbent core 101 having the above structure is thin and has a low basis weight.

  Since the superabsorbent polymer is stably held in the space formed by the crimped long fibers, the long fiber absorbent core 101 can hold a large amount of the superabsorbent polymer. Specifically, when viewed from the long fiber absorbent core 101 as a whole, the basis weight of the superabsorbent polymer is preferably not less than the basis weight of the long fibers, more preferably not less than 2 times, more preferably not less than 3 times. When the superabsorbent polymer is not sufficiently embedded in the web, hot-melt adhesives, various binders (such as acrylic emulsion adhesives), sugar derivatives such as carboxymethylcellulose and ethylcellulose, thermoplastic resins such as polyethylene, etc. Can be appropriately added to the web. Furthermore, you may use together the sheet | seat etc. which gave uneven | corrugated processing or flocking.

  In the long fiber absorbent core 101 shown in FIG. 9, the long fibers constituting the web 102 are oriented in one direction in the plane direction of the long fiber absorbent core 101. When the liquid is absorbed by the long fiber absorbent core 101 due to the orientation of the long fibers in one direction, the liquid diffuses preferentially in the orientation direction of the long fibers. Conversely, diffusion in the direction perpendicular to the orientation direction of the long fibers is suppressed. When the long fibers are oriented in the width direction of the disposable diaper, liquid leakage from the front part of the diaper (pre-leakage) is effectively prevented. In the width direction, the liquid leakage prevention property is improved by the leak-proof cuff 6 or the leg elastic member 81.

  The degree of orientation of the long fibers is preferably 1.2 or more, particularly 1.4 or more in terms of the degree of orientation. In this embodiment, the degree of orientation is measured using Microwave molecular orientation analyzer MOA-2001A manufactured by KANZAKI. The sample size is 100 mm in the longitudinal direction and 50 mm in width, and the average value of three points is the degree of orientation. When the sample size is less than this size, measurement is performed by arranging a plurality of samples so as not to overlap each other.

  One means for further preventing pre-leakage is to use a linear long fiber web. This is because such a long fiber is superior in liquid diffusibility in the orientation direction of the long fiber as compared with a long fiber web having crimps. From this point of view, it is preferable that a part of the crimped long fibers in at least one of the plurality of webs 102 is stretched to be in a linear state. For example, when the long fiber absorbent core 101 has two layers of webs 102, by stretching a portion of the web 102 on the topsheet side, for example, the crimped long fibers located in the center in the longitudinal direction, The excreted liquid can be preferentially guided in the lateral direction of the absorber. Alternatively, in addition to the web 102 made of crimped long fibers, the same effect can be obtained by further using a hydrophilic long fiber web having no crimps. For example, it is possible to use two layers of webs 102 made of crimped long fibers and arrange a web made of long fibers without crimps on the upper layer via a polymer layer.

  When the long fibers are oriented in the longitudinal direction of the diaper (diaper front-rear direction), liquid leakage (lateral leakage) from the side of the diaper is effectively prevented. Also in this case, since the front and rear ends of the absorbent main body 5 are bonded so as to cover the sheet 11 having water repellency, liquid leakage is further prevented. In addition, liquid leakage can be prevented by disposing a leak-proof cuff at the front and rear ends of the absorbent main body 5.

  In the long fiber absorbent core 101, since the superabsorbent polymer is held in the space formed by the crimped long fibers, the polymer is unlikely to move or fall off significantly, and the wearer's intense movement This also prevents the long fiber absorbent core 101 from being broken. In order to make these effects more prominent and to reduce the “sharpness” that occurs when the superabsorbent polymers rub against each other, the overlapping webs 102, 102 are bonded to each other in the long fiber absorbent core 101. Has been. In this case, the overlapping webs 102 and 102 are adhered in a dotted pattern so that the preferential diffusion of the liquid in the orientation direction of the long fibers described above is not inhibited. Adhering in the form of scattered dots means that the shape of the bonding points does not have great anisotropy, and such bonding points are uniformly distributed over the entire area in the plane direction of the web 102. Say. As a typical bonding mode, there is a mode in which the overlapping webs 102 and 102 are bonded by a large number of small dot-shaped bonding points. For example, a method of applying a hot melt pressure-sensitive adhesive by a spray method may be used as the dotted adhesive. Examples of the spray method include a slot spray method, a curtain spray method, a melt blown method, and a spiral spray method. When such a coating method is used, not only the webs 102 are bonded to each other, but also the web 102 and a part of the superabsorbent polymer may be bonded.

  The long fiber absorptive core 101 may be composed of only a laminate of the web 102 and the polymer layer 103, or the laminate may be wrapped with paper such as tissue paper or non-woven fabric. Further, a dry pulp sheet or a fluff pulp stacking layer may be disposed on the upper and lower surfaces of the laminate of the web 102 and the polymer layer 103, respectively, and the whole of the laminate may be wrapped with paper or nonwoven fabric such as tissue paper. It may be rare. The long fiber absorbent core 101 has a thickness of preferably 10 mm or less, more preferably 5 mm or less, regardless of the form of the long fiber absorbent core 101.

  Next, the preferable manufacturing method of the long fiber absorptive core 101 mentioned above is demonstrated. First, a long fiber web having the above-described crimp rate is prepared. The web is opened by a predetermined means. For the opening, for example, an air opening device using compressed air can be used. Next, the web 102 made of opened long fibers is stretched to a predetermined length. In this case, it is not necessary to stretch the long fibers completely, and it is sufficient to stretch the superabsorbent polymer so as to be stably embedded and held in the web 102.

Under the state in which the long fibers are stretched, various adhesives such as a hot melt pressure-sensitive adhesive are applied to the web 102 by a contact method such as a roll coater method or a screen printing method, or a non-contact method such as a spray method. For the coating, spray-type coating that allows easy switching of each pattern and adjustment of the amount of the adhesive in a non-contact manner is preferable, and spray coating that can successfully perform dotted adhesion is preferably used. Examples of the spray method include a slot spray method, a curtain spray method, a melt blown method, and a spiral spray method. The adhesive is preferably applied in such a low amount that does not impede the permeation of the liquid between the webs. From this viewpoint, the coating amount of the adhesive is preferably ³ to 30 g / m ² , particularly 5 to 15 g / m ² .

  After the application of the adhesive is completed, the superabsorbent polymer is spread on the web 102 in layers. After the completion of spraying, a web 102 prepared separately is overlaid. Next, the stretched state of the long fiber is released. As a result, the stretched long fibers contract. As a result, the superabsorbent polymer is retained in the space formed by the shrinkage of the long fibers. In this way, the superabsorbent polymer is buried and supported in the web 102. As a result, the two webs 102 are bonded in a dotted pattern.

  Alternatively, after the superabsorbent polymer is sprayed on the web 102, a plurality of intermediates obtained by releasing and contracting the stretched state of the web 102 are prepared, and finally the intermediates are superposed. Thereby, the long fiber absorptive core 101 can also be obtained. In this case, since the polymer layer 103 is positioned on the uppermost layer of the long-fiber absorbent core 101, there is a concern that the superabsorbent polymer may move or drop off, but tissue paper or nonwoven fabric is used. Such inconvenience can be avoided by wrapping the entire long fiber absorbent core 101.

  Another example of the long fiber absorbent core will be described with reference to FIGS. About the point which is not demonstrated especially about the long fiber absorptive core shown in FIGS. 10-12, the description explained in full detail regarding the long fiber absorptive core shown in FIG. 9 is applied suitably. Moreover, in FIGS. 10-12, the same code | symbol is attached | subjected to the same member as FIG. 10 to 12, the upper side of each figure is the skin contact surface side, and the lower side is the non-skin contact surface side.

  A long fiber absorbent core 101 shown in FIG. 10A is composed of a single layer web 102. A superabsorbent polymer is uniformly embedded and supported in the web 102. Similarly to the long fiber absorbent core 101 shown in FIG. 10 (a), the long fiber absorbent core 101 shown in FIGS. 10 (b) and 10 (c) is composed of a single layer web 102. Is embedded and carried on the skin contact surface side or the non-skin contact surface side with respect to the thickness direction of the web 102.

  A long fiber absorbent core 101 shown in FIG. 11A has a structure in which a web 102 is stacked on a fluff pulp piled fiber layer 104. A superabsorbent polymer is embedded and supported in the web 102. A long fiber absorptive core 101 shown in FIG. 11B has a structure in which a plurality of laminated bodies 105 each having a web 102 laminated on a fluff pulp piled fiber layer 4 are laminated. A long fiber absorbent core 101 shown in FIG. 11C is obtained by mixing a superabsorbent polymer in the fluff pulp pile fiber layer 4 in the long fiber absorbent core 101 shown in FIG. . As is obvious to those skilled in the art, it is possible to construct a laminate as shown in FIG. 11B using the long fiber absorbent core 101 shown in FIG. Furthermore, it is also possible to form a laminate as shown in FIG. 11B by using the absorber shown in FIGS. 11A and 11C. A long fiber absorbent core 101 shown in FIG. 11 (d) is obtained by inverting the stacking relationship between the fluff pulp stacking layer 4 and the web 102 in the absorbent body shown in FIG. 11 (c).

  The long fiber absorptive core 101 shown in FIGS. 12A and 12B has a structure in which webs 102 are disposed above and below a fluff pulp stacking layer 104, respectively. In the absorbent body shown in FIG. 12A, in each web 102, the superabsorbent polymer is biased and carried on the skin non-facing surface side of the web 102. On the other hand, in the absorbent body shown in FIG. 12 (b), in the upper web 102, the superabsorbent polymer is biased and carried on the skin non-facing surface side of the web 102, whereas the lower side In the web 102, the superabsorbent polymer is biased and carried on the skin facing surface side of the web 102. A long fiber absorbent core 101 shown in FIG. 12C has a hydrophilic long fiber web 106 that does not contain a superabsorbent polymer disposed below the web 102 in which the superabsorbent polymer is embedded and supported. Has a structured.

  In addition to the superabsorbent polymer, other particles such as activated carbon, silica, alumina, titanium oxide, various viscosity minerals (zeolite, sepiolite, bentonite, cancrinite, etc.), etc. are contained in the web. Agents and antibacterial agents) can coexist. In addition, the long fibers constituting the web are improved for the purpose of improving the web shape retention, improving the web compression recovery, making the web less likely to be kinked, and improving the web transportability. Are preferably joined. In addition, as another method for improving the web shape retention, a method of superimposing sheet materials such as paper and non-woven fabric on the upper and lower sides of the web and bonding the web and the sheet material with an adhesive or heat-sealing. Is mentioned.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, the range of this invention is not restrict | limited to this embodiment. For example, in the above embodiment, since the side seal portion S is that of the embodiment that is located directly beside the diaper 1, the virtual development view and the development view of the outer packaging material 11 coincide with each other. The present invention can be similarly applied to a diaper in which the side seal portion is biased to the front side or the rear side from the side of the diaper (for example, the diaper described in Patent Document 1 described at the beginning).

  Moreover, in the diaper 1 of the said embodiment, although the absorptive core 4 was divided in the diaper crotch part C, the absorptive core 4 may not be so divided. The absorbent core is preferably composed of a long fiber absorbent core as a whole, but a part of the absorbent core is composed of a pulp fiber pile or a mixture of pulp fibers and a super absorbent polymer. May be.

It is a perspective view which shows one Embodiment of the underpants type disposable diaper of this invention. It is a disassembled perspective view which shows the state before assembling the diaper shown in FIG. It is a top view which shows the expansion | deployment state of the outer packaging material in FIG. It is a top view which shows another embodiment of the diaper of this invention. It is explanatory drawing which shows an iliac bone. It is explanatory drawing which shows the measuring method of upper anterior iliac spine height front and back length. Fig.9 (a) is a perspective view which shows another embodiment of the diaper of this invention, FIG.9 (b) is a top view which shows the unfolded state of the diaper shown to Fig.9 (a). It is a top view which shows the structure of the absorptive core of the diaper shown in FIG. FIG. 9 is a schematic cross-sectional view showing an example of a long fiber absorbent core that can be employed as the whole or a part of the absorbent core of the pants-type disposable diaper of the present invention. Fig.10 (a)-(c) is a schematic cross section which shows the other example of the long fiber absorptive core which can be employ | adopted as the whole or a part of absorptive core of the underpants type disposable diaper of this invention. Fig.11 (a)-(d) is a schematic cross section which shows the other example of the long fiber absorptive core which can be employ | adopted as the whole or a part of absorptive core of the underpants type disposable diaper of this invention. 12 (a) to 12 (c) are schematic cross-sectional views showing still another example of the long fiber absorbent core that can be adopted as the whole or a part of the absorbent core of the pants-type disposable diaper of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pants type disposable diaper 2 Top sheet 3 Back sheet 4 Absorbent core 4a, 4c Central absorber 4b Side absorber 5 Waist opening 6 Leg opening 71 1st area 72 2nd area

Claims (4)

A waist opening and a pair of leg openings, comprising: an absorbent main body having an absorbent core; and an outer packaging material positioned on the non-skin contact surface side of the absorbent main body and fixing the absorbent main body A pants-type disposable diaper in which is formed,
The absorbent core includes a web of long fibers having hydrophilicity, the long fibers have a crimp rate of 40 to 90% and are oriented in the planar direction of the absorbent core;
Elastic members along the peripheral shape of the leg opening are not arranged on both sides of the outer packaging material in the crotch part of the diaper,
Considering a virtual development view obtained by virtually cutting and expanding the diaper in the vertical direction at a position next to the diaper,
In the front side, the angle formed by the virtual longitudinal cutting line and the leg hole intersecting this is less than 90 degrees,
In the rear side portion, the leg hole has a convex shape outwardly from the position P1 of the lower end portion of the virtual longitudinal cutting line and the straight line P1-P2 connecting the position P2 of the intersection of the longitudinal center line and the leg hole. Further, the position on the straight line P1-P2 where the distance between the straight line P1-P2 and the leg hole is the largest in the convex shape portion is the center of the virtual development view more than the midpoint of the straight line P1-P2. And the distance between the position and the midpoint is 0 to 50 mm,
The length T1 from the lower end of the virtual vertical cutting line on the front side to the minimum width in the virtual development view and the length from the lower end of the virtual vertical cutting line on the rear side to the minimum width in the virtual development drawing The ratio with T2, T1: T2 is 25: 75-40: 60,
When wearing a diaper, the wearing pressure of the region that contacts the site from the wearer's iliac crest to the upper anterior iliac spine is made higher than the wearing pressure of the waist opening ,
The region is located between the waist opening and the leg opening in each of the ventral side and the back side of the diaper, and the mounting pressure of the region in each of the ventral side and the back side is 1.1. Pants-type disposable diapers that are rated at ~ 2.5 kPa . The absorbent core is separated into a central absorbent body and a pair of side absorbent bodies located on both sides of the central absorbent portion at least at the crotch, and an elastic member for raising the side of the absorbent main body is provided. The pants-type disposable diaper according to claim 1 , wherein the pants-type disposable diaper is disposed near the outer edge of each of the pair of side absorbers. Wherein when considering a virtual development view, and the lower end portion of the imaginary longitudinal cut line in the front side, the distance between the lower end portion of the imaginary longitudinal cutting line at the back side of a is claim 1 or 2, wherein 210~280mm Pants Type disposable diaper. The outer packaging material is a pants-type disposable diaper according to any one of 1 to 3 , wherein a peripheral portion of the leg hole in the rear side portion is extendable in a direction orthogonal to the peripheral portion.

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