HK1178777B - Disposable diaper - Google Patents

Abstract

An outer covering sheet (4) of a pants-type disposable diaper (1) has a front part and a back part (403) to be positioned on a front side and a back side of a wearer, and a middle part lying between the both. An absorbent body (20) is attached on the outer covering sheet (4), to absorb excrement from the wearer. In the absorbent body (20), both end portions positioned in the front part and the back part (403) are folded toward the inner surface (40) of the outer covering sheet (4) to be bonded on the inner surface (40). It is therefore possible to prevent skin of the wearer from being irritated by edges (241) of the both end portions of the absorbent body (20) when the disposable diaper (1) is worn.

Description

Disposable diaper having a disposable diaper

Technical Field

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

Background

Pants-type disposable diapers have a waist opening at an upper end portion and a pair of leg openings at a lower portion, and are generally a type of absorbent product for receiving excrement from a wearer. Such a disposable diaper has an outer covering sheet in which a front portion and a rear portion to be positioned on the front and rear sides of a wearer are continuous with each other through a middle portion, and left and right end portions of the front portion are bonded to left and right end portions of the rear portion, respectively, to form a waist opening and a pair of leg openings. Further, an absorbent body for absorbing excrement from a wearer is attached to the outer covering sheet so as to be arranged from the front portion to the rear portion. In japanese patent application laid-open No. 2007-979797979, there is disclosed a pair of end holding sheets which are adhered to the front and rear portions to cover both ends of the absorbent body in the longitudinal direction, respectively, and which can prevent the skin of the wearer from being irritated by the end edges of the absorbent body

The disposable absorbent product disclosed in japanese patent application laid-open No.8-66426 (document 2) has a heavy portion due to the absorbent panel formed by folding the absorbent layer (absorbent core) on itself. In the absorbent product of document 2, since they are covered with the top sheet, the absorbent layer and the absorbent panel do not directly contact the wearer's skin.

In the disposable diaper having the end holding sheet, the texture in the waist region becomes harder, the air permeability decreases and the manufacturing cost increases, as compared with the disposable diaper in which the end holding sheet is omitted. On the other hand, in a disposable diaper in which the end holding sheet is omitted, there may be the following cases: when end rolling or the like occurs, the end edge of the absorbent body may irritate the skin of the wearer. Therefore, there is a need for a disposable diaper in which the skin of the wearer can be prevented from being irritated by the end edges of the absorbent body while the end holding sheet is omitted.

Disclosure of Invention

The present invention provides a pants-type disposable diaper having a waist opening at an upper end portion and a pair of leg openings at a lower portion. The object of the invention is to prevent the skin of the wearer from being irritated by the end edges of the absorbent body.

The disposable diaper according to the present invention comprises: an outer covering sheet folded in an intermediate portion between front and rear portions of a foreign language to be positioned on front and rear sides of a wearer, left and right end portions of the front portion being bonded to left and right end portions of the rear portion, respectively, to form waist openings at upper end portions of the front and rear portions and a pair of leg openings below the front and rear portions, the pair of leg openings being positioned on left and right sides of the intermediate portion; and a sheet-like absorbent body attached on an inner surface of the outer covering sheet to contact the wearer and absorb excrement from the wearer, the absorbent body being arranged from the front portion to the rear portion; wherein one end portion of the absorbent body located at the front portion or the rear portion is folded toward the inner surface of the outer covering sheet so as to be bonded on the inner surface.

In the present invention, when the disposable diaper is worn, the skin of the wearer can be prevented from being irritated by the edge of one end portion of the absorbent body.

According to a preferred embodiment of the present invention, the absorbent body has an intermediate bonded portion located at the intermediate portion, and the intermediate bonded portion is bonded to the inner surface of the outer covering sheet, and a portion of the absorbent body located between the folded position of the one end portion and the intermediate bonded portion is not bonded to the one end portion and the outer covering sheet. Therefore, the vicinity of the folded position in the absorbent body can be brought into close contact with the wearer.

According to another preferred embodiment of the present invention, the entire edge of one end portion of the absorbent body is located between the inner surface of the outer covering sheet and the other portion of the absorbent body. Therefore, the skin of the wearer can be surely prevented from being irritated by the edge of the one end portion of the absorbent body.

According to an aspect of the invention, the absorbent body comprises: an absorbent core; a back sheet positioned between the inner surface of the outer cover sheet and the absorbent core; and a top sheet positioned on the inner surface of the absorbent core; the back sheet and the top sheet are bonded to each other in one end portion of the absorbent body, and the folded position of the one end portion overlaps with the edge of the absorbent core or is located between the edge of the absorbent core and the waist opening.

In this case, the entire edge of one end portion of the absorbent body is located between the inner surface of the outer covering sheet and the absorbent core. This can surely prevent the skin of the wearer from being irritated by the edge of the one end portion of the absorbent body. Preferably, the absorbent body further includes a pair of side wall portions which are located on the left and right side portions of the absorbent body and stand from the top sheet, and which are bonded to the top sheet in the folded position.

According to another aspect of the present invention, the disposable diaper further includes an elastic member that contracts one end portion of the absorbent body in a width direction of the absorbent body to form a wrinkle in the one end portion. Therefore, the skin of the wearer can be surely prevented from being irritated by the edge of the one end portion of the absorbent body.

More preferably, the other end portion of the absorbent body is folded toward the inner surface of the outer covering sheet so as to be bonded to the inner surface. This can prevent the skin of the wearer from being irritated by the edges of the two end portions of the absorbent body.

These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

Drawings

Fig. 1 is a perspective view showing the appearance of a disposable diaper provided according to a first preferred embodiment.

Fig. 2 is a plan view of the disposable diaper in an unfolded state.

Fig. 3 is a sectional view of a disposable diaper.

Fig. 4 is a sectional view of a disposable diaper.

Fig. 5 is a view for explaining a part of a manufacturing process of an absorbent body.

Fig. 6 is a view showing a disposable diaper provided according to a second preferred embodiment.

FIG. 7 is a sectional view of a disposable diaper.

Fig. 8 is a view showing a disposable diaper provided according to a third preferred embodiment.

Fig. 9 is a view showing another example of a disposable diaper.

Detailed Description

Fig. 1 is a perspective view showing the appearance of a disposable diaper 1 provided according to a first preferred embodiment of the present invention. As shown in fig. 1, the disposable diaper 1 is a pants-type (i.e., pull-up type) diaper having a waist opening 11 at an upper end portion (an end portion which is an upper side of fig. 1) and a pair of leg openings 12 at a lower portion, and is for receiving excrement from a wearer. The up-down direction of fig. 1 is not limited to the gravity direction.

Fig. 2 is a plan view of the disposable diaper 1 in an unfolded state, and in fig. 2, the disposable diaper 1 can be viewed from the wearer side. As shown in fig. 2, the disposable diaper 1 has an outer covering sheet 4 and a sheet-like absorbent body (absorber) 20 attached to an inner surface 40 (i.e., a wearer-facing surface) of the outer covering sheet 4 to absorb excrement from a wearer.

In the disposable diaper 1, the upper part in fig. 2 is to be located on (cover) the front side (abdomen side) of the wearer, and the lower part in fig. 2 is to be located on the back side of the wearer. In the following description, portions of the disposable diaper 1 (and portions of the outer covering sheet 4) to be positioned on the front and rear sides of the wearer are referred to as "front portion 401" and "rear portion 403", respectively, and a portion between the front portion 401 and the rear portion 403 that faces the crotch region of the wearer is referred to as "middle portion 402". The middle portion 402 is continuous with the front portion 401 and the rear portion 403. With respect to the left-right direction (lateral direction) in fig. 2, the width of the intermediate portion 402 is smaller than those of the front portion 401 and the rear portion 403. Hereinafter, the left-right direction in fig. 2 is referred to as "diaper width direction".

In the manufacture of the disposable diaper 1, the outer covering sheet 4 is folded together with the absorbent body 20 at the intermediate portion 402. In a state where the intermediate portion 402 is located on the lower side, the left and right end portions of the front portion 401 are bonded to the left and right end portions of the rear portion 403, respectively, by means of thermal bonding (heat sealing) under heat and pressure. As described above, since both side end portions of the front portion 401 are respectively bonded to both side end portions of the rear portion 403, as shown in fig. 1, the waist opening 11 is formed at the upper end portions of the front portion 401 and the rear portion 403, and the pair of leg openings 12 located to the left and right of the middle portion 402 are formed below the front portion 401 and the rear portion 403.

Fig. 3 is a cross-sectional view of the disposable diaper 1 taken along the line III-III in fig. 2 (taken at the intermediate portion 402). In fig. 3, the respective constituent parts of the disposable diaper 1 are drawn slightly apart from each other for convenience of illustration.

As shown in fig. 3, the outer covering sheet 4 has an inner sheet 41 and an outer sheet 42, and the outer sheet 42 is laminated on the lower side (i.e., the side not facing the wearer) of the inner sheet 41. As shown in fig. 2, the plurality of leg elastic members 43 and the plurality of waist elastic members 44 are bonded between the inner sheet 41 and the outer sheet 42 by a hot melt adhesive or the like. In the disposable diaper 1, by contraction of the leg elastic members 43, the inner sheet 41 and the outer sheet 42 (see fig. 3) contract and form leg gathers. And, the waist gathers are formed by contraction of the waist elastic member 44. Outside the plurality of waist elastic members 44, a plurality of waist elastic members 44 located in the vicinity of the edges of the waist opening 11 (see fig. 1) are densely arranged, and by these waist elastic members 44, the disposable diaper 1 is tightly fitted around the waist of the wearer.

As shown in fig. 2 and 3, the absorbent body 20 has a sheet-like main body portion 2 and a pair of side sheets 3 located on both side portions of the main body portion 2 (i.e., both end portions of the main body portion 2 in the diaper width direction), and the pair of side sheets 3 extends across almost the entire length of the main body portion 2 in the longitudinal direction (i.e., the up-down direction in fig. 2). As shown in fig. 3, the main body portion 2 has a top sheet 21, a back sheet 23, and an absorbent core 22, and the absorbent core 22 is located between the top sheet 21 and the back sheet 23. The back sheet 23 is bonded to the outer covering sheet 4 by a hot melt adhesive or the like to fix the absorbent body 20 to the outer covering sheet 4. The outline of the absorbent core 22 is drawn by thick dashed lines in fig. 2 to facilitate understanding of the figure. As shown in fig. 2, the width of the absorbent core 22 at each end portion in the longitudinal direction is larger than the width at the middle portion in the longitudinal direction. In other words, the absorbent core 22 is formed in the form of an hourglass.

As shown in fig. 3, each side sheet 3 has a strip-like adhesive portion 33 and a side wall portion 34. The adhesive 33 is one of two portions separated by a fold line 39 extending across almost the entire length of the side sheet in the longitudinal direction, and the adhesive 33 is located on the main body portion 2. The side wall portion 34 is the other of the two portions. The adhesive portion 33 is located near the side edge of the main body portion 2, spans almost the entire length of the main body portion in the longitudinal direction, and is adhered on the upper side (i.e., the wearer's side) of the main body portion 2 by a hot melt adhesive.

The side wall portion 34 is continuous from the bonded portion 33 by a fold line 39. In the vicinity of both end portions of the side wall portion 34 in the longitudinal direction, the side wall portion 34 is arranged on the bonded portion 33 and fixed on the bonded portion 33 by thermal bonding, ultrasonic bonding, or hot melt adhesive. In fig. 2, hatching lines are drawn at each portion 341 of the side wall portion 34 fixed on the adhesive portion 33 for easy understanding of the drawing. As shown in fig. 2 and 3, the side wall portion 34 has an upright portion 342 that stands upright from the top sheet 21 on its middle portion in the longitudinal direction. In the side wall portion 34 shown in fig. 3, the elastic member 35 is bonded on the free edge of the standing portion 342, and wrinkles are formed in the standing portion 342 by contraction of the elastic member 35.

Fig. 4 is a sectional view of the disposable diaper 1 (in cross section) taken along the line IV-IV in fig. 2. In fig. 4, the vicinity of the end of the absorbent body 20 located in the rear portion 403 is drawn. As shown in fig. 2, the absorbent body 20 is positioned from the front portion 401 to the rear portion 403 through the intermediate portion 402. As shown in fig. 4, the end of the absorbent body 20 located in the rear portion 403 is folded (folded back) toward the inner surface 40 of the outer covering sheet 4 so as to be bonded on the inner surface 40. In detail, in the longitudinal direction of the absorbent body 20, the back sheet 23 positioned between the inner surface 40 of the outer covering sheet 4 and the absorbent core 22 and the top sheet 21 positioned on the inner surface of the absorbent core 22 (i.e., the surface facing the wearer) are each longer than the absorbent core 22, and portions of the back sheet 23 and the top sheet 21 protruding from the edge 221 of the absorbent core 22 (i.e., the edge almost in the diaper width direction) in the longitudinal direction overlap with each other (are positioned on each other) and are bonded to each other. In the following description, in the end portion of the absorbent body 20 located in the rear portion 403, portions of the rear sheet 23 and the top sheet 21 bonded to each other (the portions are denoted by reference numeral 24 in fig. 4) are generally referred to as "bonded end portions". The length of the bonded end portion 24 along the longitudinal direction of the absorbent body 20 is, for example, 20 millimeters (mm).

The bonded end portion 24 is folded toward the outer covering sheet 4 in an integrally formed manner (as a unit) in the vicinity of the edge 221 of the absorbent core 22, and the surface of the bonded end portion 24 continuous from the inner surface of the absorbent body 20 (i.e., the surface of the top sheet 21) is bonded on the inner surface 40 of the outer covering sheet 4 by hot melt adhesive or the like. Most of the bonded end portions 24 are located between the absorbent core 22 and the inner surface 40 of the outer coversheet 4. Also, the middle portion 201 of the absorbent body 20 in the longitudinal direction is bonded on the inner surface 40 of the outer covering sheet 4, and hereinafter, the portion 201 of the absorbent body 20 is referred to as "middle bonded portion 201". In fig. 4, the adhesive layer between the main body portion 2 and the outer covering sheet 4 is drawn by a thick solid line identified by reference numeral 49 (the same applies to fig. 7 mentioned later). In the disposable diaper 1 shown in fig. 4, a portion of the absorbent body 20 between the folded position of the bonded end portion 24 (i.e., the position identified by reference numeral 240 in fig. 4) and the intermediate bonded portion 201 is not bonded to the bonded end portion 24 and the outer covering sheet 4, and the end portion of the absorbent core 22 located in the back portion 403 is slightly bent toward a direction away from the outer covering sheet 4.

In fact, since the bonded end portion 24 is folded almost along the edge 221 of the absorbent core 22, the entire edge 241 of the tip of the bonded end portion 24 is positioned almost between the inner surface 40 of the outer covering sheet 4 and the absorbent core 22 (see fig. 2). In the disposable diaper 1 in a state where the left and right end portions of the front portion 401 are bonded to the left and right end portions of the back portion 403, respectively (see fig. 1), as shown in fig. 4, the distance between the folded position 240 of the bonded end portion 24 and the waist opening 11 is smaller than the distance between the edge 221 of the absorbent core 22 and the waist opening 11, and the bonded end portion 24 is folded with avoiding the absorbent core 22. In the disposable diaper 1, the folded position 240 of the bonded end portion 24 may almost overlap with the edge 221 of the absorbent core 22. Also in this case, the bonded end portions 24 are folded away from the absorbent core 22.

As already described, each side sheet 3 (see fig. 2 and 3) extends over the entire length of the top sheet 21 and the back sheet 23 with respect to the longitudinal direction. In the bonded end portion 24, the bonded portion 33 of the side sheet 3 is bonded on the top sheet 21, and the side wall portion 34 is arranged and fixed on the bonded portion 33. As described above, the pair of side walls 34 disposed on the left and right side portions of the absorbent body 20 are bonded to the top sheet 21 at the folding positions 240 of the bonded end portions 24, and the bonded end portions 24 can be easily folded together with the pair of side sheets 3 in the manufacture of the disposable diaper 1.

In the disposable diaper 1, the other end portion of the absorbent body 20 located in the front portion 401 has the same structure as the end portion located in the rear portion 403 (i.e., the other end portion is also the bonded end portion 24), and it is folded toward the inner surface 40 of the outer covering sheet 4 so as to be bonded on the inner surface 40.

The top sheet 21 is made of a liquid-permeable sheet material, and the top sheet 21 immediately captures moisture in the excreta from the wearer and moves the moisture into the absorbent core 22. For example, the top sheet 21 is a liquid-permeable nonwoven fabric made of hydrophobic fibers (polypropylene, polyethylene, polyester, polyamide, nylon, etc.) in which hydrophilic treatment is performed on the surface thereof by a surfactant, and examples of nonwoven fabrics for the top sheet 21 are point-bonded nonwoven fabrics, air-through nonwoven fabrics, and spunbond nonwoven fabrics. A nonwoven fabric (e.g., spunlace nonwoven fabric) made of hydrophilic fibers such as cellulose, rayon, cotton, etc. may be used as the top sheet 21.

The absorbent core 22 is formed by covering a mixture of hydrophilic fibers such as crushed fibers or cellulose fibers and a high-absorbent material such as a particulate high-absorbent polymer (e.g., SAP (super absorbent polymer)) or high-absorbent fibers in tissue, a liquid-permeable nonwoven fabric, or the like, and the absorbent core 22 is capable of quickly absorbing and retaining moisture that has passed through the top sheet 21. Tissue paper, liquid-permeable nonwoven fabric, or the like for covering the hydrophilic fibers is bonded to the hydrophilic fibers and the absorbent material by a hot-melt adhesive to prevent deformation of the hydrophilic fibers and dropping of the absorbent material (in particular, dropping after absorbing moisture). In the present embodiment, the absorbent core 22 includes pulp fibers and SAP (super absorbent polymer).

Used as the back sheet 23 is a waterproof or liquid-impermeable nonwoven fabric (e.g., spunbond nonwoven fabric, meltblown nonwoven fabric or SMS (spunbond-meltblown-spunbond) nonwoven fabric) made of hydrophobic fibers or a waterproof or liquid-impermeable plastic film. The rear sheet 23 can prevent moisture of excrement or the like that has reached the rear sheet 23 from leaking to the outside of the main body 2. In the case where a plastic film is used for the back sheet 23, from the viewpoint of preventing perspiration in the disposable diaper 1 and providing a comfortable feeling to the wearer, it is preferable to use a plastic film having permeability (breathability).

Used as the sheet main body of the side sheet 3 is a waterproof or liquid-impermeable nonwoven fabric (e.g., spunbond nonwoven fabric, meltblown nonwoven fabric or SMS nonwoven fabric) made of hydrophobic fibers. For example, polyurethane yarn, strip-like polyurethane film, yarn-like or strip-like natural rubber, or the like is used as the elastic member 35. In the present embodiment, a polyurethane yarn is used as the elastic member 35.

In a manner similar to the back sheet 23, a waterproof or liquid-impermeable nonwoven fabric made of hydrophobic fibers, or a waterproof or liquid-impermeable plastic film is used as the inner sheet 41 and the outer sheet 42 of the outer covering sheet 4. A laminated sheet of nonwoven fabric and plastic film may be used. Preferably, the plastic film has permeability (breathability). In a manner similar to the top sheet 21, a nonwoven fabric made of hydrophilic fibers or a liquid-permeable nonwoven fabric made of hydrophobic fibers (in which hydrophilic treatment is performed) may be used as the inner sheet 41 and the outer sheet 42.

For example, as the leg elastic members 43 and the waist elastic members 44, polyurethane yarn, strip-like polyurethane film, yarn-like or strip-like natural rubber, or the like is used in a manner similar to the elastic members 35 of the side sheet 3. In the present embodiment, polyurethane yarn is used for the leg elastic members 43 and the waist elastic members 44.

When the disposable diaper 1 shown in fig. 1 is worn on a wearer, both legs of the wearer are inserted into the pair of leg openings 12 through the waist opening 11, and then the disposable diaper 1 is pulled up so as to be around the waist of the wearer. At this time, since the entire edges of both end portions of the absorbent body 20 shown in fig. 2 (i.e., the edges 241 of the adhesive end portions 24) are covered by the other portions of the absorbent body 20, the edges 241 do not contact the wearer's skin. Further, since both end portions of the absorbent core 22 located in the front portion 401 and the rear portion 403 are bent toward the wearer, the portion of the absorbent body 20 located near the edge 221 of the absorbent core 22 is in close contact with the wearer.

As described above, in the absorbent body 20 of the disposable diaper 1, in order to directly contact with the wearer and absorb excrement from the wearer, both end portions located in the front portion 401 and the back portion 403 are folded back toward the inner surface 40 of the outer covering sheet 4 so as to be bonded on the inner surface 40. Therefore, when the disposable diaper 1 is worn, the skin of the wearer can be prevented from being irritated by the edges 241 of both end portions of the absorbent body 20. In the disposable diaper 1 in which the end holding sheet is omitted, the texture in the waist region is softened and the air permeability is increased when compared with the disposable diaper having the end holding sheet, so that the feeling of wearing the disposable diaper 1 is improved, and the manufacturing cost of the diaper can also be reduced.

In the disposable diaper 1, the entire edge 241 of each end portion of the absorbent body 20 is located between the inner surface 40 of the outer covering sheet 4 and the other portion of the absorbent body 20. Therefore, it is determined that the skin of the wearer can be prevented from being irritated by the edge 241.

Further, the portion of the absorbent body 20 (see fig. 4) arranged from the folded position 240 of each end portion to the intermediate bonding portion 201 is not bonded to the end portion and the outer covering sheet 4. Therefore, the vicinity of the folded position 240 in the absorbent body 20 can be brought into close contact with the wearer. Thus, the excreta can be prevented from leaking out through the vicinity of the folded position 240. Leakage of excrement often occurs particularly in the rear side of the wearer. Therefore, in this connection, it is preferable that at least the portion located between the folded position 240 of the bonded end portion 24 in the rear portion 403 and the intermediate bonded portion 201 is not bonded to the turned-down portion of the bonded end portion 24 and the outer covering sheet 4.

Next, another example of the absorbent body in the disposable diaper 1 will be discussed. Fig. 5 is a view for explaining a part of the manufacturing process of the absorbent body 20 according to this other example. In the manufacturing process of the absorbent body 20 according to this other example, in which the absorbent body is continuous in the manufacturing process, the continuous sheet 9 is continuously moved in the direction shown by the arrow identified with reference character a1 in fig. 5 (i.e., the direction is the longitudinal direction of the continuous sheet 9 and is hereinafter referred to as "feeding direction"). In the continuous sheet 9, a plurality of absorbent cores 22 are located between the strip-shaped sheet to become the rear sheet and the strip-shaped sheet to become the top sheet, and the absorbent cores 22 are arranged at intervals in the feeding direction a 1. In fact, a pair of strip-like sheets to become side sheets is also bonded in the continuous sheet 9.

By the first cutter 81, concave portions (notch portions) 91 are formed on both side portions of each region between two adjacent absorbent cores 22 located in the strip-like continuous sheet 9 passing under the first cutter 81. In fig. 5, the edge of the portion to be cut by the first cutter 81 in the continuous sheet 9 is drawn by a chain double-dashed line identified by reference numeral 911, and an almost semicircular portion is cut in each side portion of the continuous sheet 9. Therefore, in the region between two adjacent absorbent cores 22, the width of the continuous sheet 9 (i.e., the width in the direction perpendicular to the feeding direction a 1) is smaller than the width of the other portions.

In the continuous sheet 9 passing under the second cutter 82, the area between two adjacent absorbent cores 22 is cut by the second cutter 82, and therefore, only the portion having one absorbent core 22 is taken out as the absorbent body 20. Specifically, as indicated by a chain double-dashed line identified by reference numeral 921 in fig. 5, the continuous sheet 9 is cut along a line perpendicular to the feeding direction a1 at the positions of the two concave portions 91 facing each other. Therefore, in each end of the absorbent body 20 cut from the continuous sheet 9, the length of the edge excluding the concave portion 91 (i.e., the length of the edge perpendicular to the feeding direction a 1) is smaller than the width of the other portion of the absorbent body 20.

When the absorbent body 20 shown in fig. 5 is fixed on the outer covering sheet 4, both end portions to be located in the front portion 401 and the rear portion 403 are folded toward the inner surface 40 of the outer covering sheet 4 at positions near the edges of the absorbent core 22 so as to be bonded on the inner surface 40. At this time, in the absorbent body 20 having an approximately rectangular shape shown in fig. 5, the left and right corners (two corners) of each end of the absorbent body 20 have chamfered shapes. Therefore, when each end portion of the absorbent body 20 is folded, even if the folding line on the absorbent body 20 is slightly inclined with respect to the longitudinal direction perpendicular to the absorbent body 20, the entire edge of the end portion can be located between the inner surface 40 of the outer covering sheet 4 and the other portion of the absorbent body 20. Therefore, in the disposable diaper 1, the skin of the wearer can be more surely prevented from being irritated by the edges of both end portions of the absorbent body 20. In the disposable diapers 1a,1b mentioned later, an absorbent body whose corner portions have chamfered shapes may be used.

Fig. 6 is a view showing a disposable diaper 1a provided according to a second preferred embodiment of the present invention, and fig. 6 corresponds to fig. 2. Fig. 7 is a sectional view of the (cross-sectioned) disposable diaper 1a taken along a line VII-VII in fig. 6. In fig. 7, the vicinity of the end of the absorbent body 20a located in the rear portion 403 is drawn. The disposable diaper 1a in fig. 6 and 7 differs from the disposable diaper 1 in fig. 2 to 4 in that the absorbent body 20a has an elastic member 25 mentioned later. The constituent elements other than those are the same as those of the disposable diaper 1 in fig. 2 to 4, and the same elements are identified by the same reference numerals.

In the absorbent body 20a shown in fig. 6 and 7, in a manner similar to the absorbent body 20 in fig. 4, the ends located in the front portion 401 and the rear portion 403 are folded toward the inner surface 40 of the outer covering sheet 4 so as to be bonded on the inner surface 40. In detail, as shown in fig. 7, the portions of the back sheet 23 and the top sheet 21 located between one edge 221 of the absorbent core 22 and their ends are bonded to each other as bonded end portions 24, and the bonded end portions 24 are folded toward the inner surface 40 of the outer covering sheet 4 so as to be bonded on the inner surface 40. In a state where the elastic member 25 is stretched, the elastic member 25 (see fig. 6) extending in the diaper width direction is bonded between the back sheet 23 and the top sheet 21 in the bonded end portion 24 (i.e., the stretched elastic member 25 is bonded in the bonded end portion 24).

In the disposable diaper 1a, the folding position 240 of the bonded end portion 24 is slightly away from the edge 221 of the absorbent core 22, and as shown in fig. 7, a first portion 2421 of the bonded end portion 24 (i.e., a portion not contacting the inner surface 40 of the outer covering sheet 4) positioned from the vicinity of the edge 221 of the absorbent core 22 to the folding position 240 and a second portion 2422 of the bonded end portion 24 (i.e., a portion contacting the inner surface 40 of the outer covering sheet 4) positioned from the vicinity of the folding position 240 to the edge 241 of the tip of the bonded end portion 24 become a double structure. In the present embodiment, the elastic member 25 is bonded to the first part 2421 described above, however, it may be bonded to the second part 2422 (which may be located in the vicinity of the edge 241). For example, polyurethane yarn, strip-shaped polyurethane film, yarn-shaped or strip-shaped natural rubber, or the like may be used as the elastic member 25. In the present embodiment, a polyurethane yarn is used as the elastic member 25 (the same applies to the elastic members 45,45a shown in fig. 8 and 9).

In the disposable diaper 1a in fig. 6 and 7, the bonded end portion 24 (the above-described first part 2421 of the bonded end portion 24) is contracted in the width direction of the absorbent body 20 (i.e., diaper width direction) by contraction of the elastic member 25 to form wrinkles in the bonded end portion 24. Therefore, the bonded end portion 24 becomes thick (bulky), and a certain space is formed between the inner surface 40 of the outer covering sheet 4 and the skin of the wearer when the disposable diaper 1a is worn in the vicinity of the bonded end portion 24. In other words, the wrinkles formed in the bonded end portions 24 act as spacers. Therefore, when the bonded end portion 24 of the absorbent body 20a is folded, even when the folding line is slightly inclined with respect to the longitudinal direction perpendicular to the absorbent body 20a and a part (e.g., a corner) of the edge 241 of the bonded end portion 24 is not covered by other parts of the absorbent body 20a, the part of the edge 241 can be prevented from contacting the wearer. As described above, in the disposable diaper 1a, the skin of the wearer can be surely prevented from being irritated by the edge 241 of the adhesive end portion 24.

Fig. 8 is a view showing a disposable diaper 1b according to a third preferred embodiment of the present invention, and fig. 8 corresponds to fig. 2. The disposable diaper 1b in fig. 8 differs from the disposable diaper 1 in fig. 2 in that the outer covering sheet 4b has an elastic member 45 mentioned later. The constituent elements other than those are the same as those of the disposable diaper 1 in fig. 2, and the same elements are denoted by the same reference numerals.

In the disposable diaper 1b in fig. 8, in a manner similar to the disposable diaper 1 in fig. 2, the bonded end portions 24 of the absorbent body 20 located in the front part 401 and the back part 403 are folded toward the inner surface 40 of the outer covering sheet 4b so as to be bonded on the inner surface 40. In each bonded end portion 24 of the absorbent body 20, the folded position 240 of the bonded end portion 24 is slightly away from the edge 221 of the absorbent core 22, and in a state where the elastic member 45 is stretched, the elastic member 45 extending in the diaper width direction is bonded to the outer covering sheet 4b at a position between the edge 221 and the folded position 240 with respect to the longitudinal direction of the absorbent body 20. In fact, in a manner similar to the leg elastic members 43 and the waist elastic members 44, the elastic members 45 are located between the inner sheet 41 and the outer sheet 42 (see fig. 4).

In the disposable diaper 1b in fig. 8, the bonded end portion 24 of the absorbent body 20 (to be exact, a part of the bonded end portion 24 bonded on the outer covering sheet 4 b) is contracted by contraction of the elastic member 45 to form wrinkles. Therefore, the bonded end portion 24 becomes thick, and a certain space is formed between the inner surface 40 of the outer covering sheet 4b and the skin of the wearer when the disposable diaper 1b is worn in the vicinity of the bonded end portion 24. Therefore, even if a part of the edge 241 of the adhesive end portion 24 is not covered by the other part of the absorbent body 20, the skin of the wearer can be prevented from being irritated by the part of the edge 241.

Fig. 9 is a view showing another example of the disposable diaper 1 b. In the disposable diaper 1b shown in fig. 9, the elastic member 45a extending in the diaper width direction is located only on an area in the outer covering sheet 4b where the absorbent body 20 exists (i.e., overlaps with the absorbent body 20). As described above, since the elastic member 45a is disposed only to the necessary portion for forming wrinkles in the bonded end portion 24 of the absorbent body 20, the volume of the polyurethane yarn used to manufacture the disposable diaper 1b can be reduced, and the manufacturing cost of the disposable diaper can be reduced. In the disposable diaper 1b in fig. 8, since the elastic member 45 is arranged across the entire width of the outer covering sheet 4b in the width direction, the polyurethane yarn to be changed into the elastic member 45 and the polyurethane yarn to be changed into the plurality of waist elastic members 44 can be cut simultaneously in the manufacture of the diaper, and the manufacture of the disposable diaper 1b can be easily achieved.

Although the preferred embodiments of the present invention have been discussed above, the present invention is not limited to the above preferred embodiments and allows various modifications.

In the disposable diaper 1,1a,1b, only one end portion of the absorbent body located in the front portion 401 or the rear portion 403 may be folded toward the inner surface 40 of the outer covering sheet. Therefore, when the disposable diaper is worn, the skin of the wearer can be prevented from being irritated by the edge of the one end portion of the absorbent body. In this case, the other end portion of the absorbent body may be covered with an end holding sheet (the end holding sheet is also referred to as an end sheet). However, from the viewpoint of preventing the skin of the wearer from being irritated by the edges of both end portions of the absorbent body, it is preferable that the other end portion of the absorbent body is also folded toward the inner surface 40 of the outer covering sheet so as to be adhered on the inner surface 40.

In the disposable diaper 1 having the absorbent body 20 whose corner portions have chamfered shapes shown in fig. 5, it is possible to surely prevent the skin of the wearer from being irritated by the edge of each end portion of the absorbent body 20. However, in the disposable diaper 1 shown in fig. 2 having the absorbent body 20 (the corners of which do not have the chamfered shape), even if a part of the edge of the end portion in the absorbent body 20 is not covered by the other part of the absorbent body 20, the body of the wearer can be distanced from the part of the edge by the thickness of the absorbent core 22, and therefore, the part of the edge does not highly irritate the skin of the wearer.

In the first to third preferred embodiments described above, since the folding position 240 of each end of the absorbent body overlaps with the edge of the absorbent core 22 or is located between the edge of the absorbent core 22 and the waist opening 11, the absorbent body can be folded while avoiding the absorbent core 22 (i.e., the absorbent core 22 is not folded). However, in certain designs of disposable diapers, the following may also be the case: the folded position of the end of the absorbent body overlaps the absorbent core 22, and a part of the absorbent core 22 is also folded together with the top sheet 21 and the back sheet 23.

In order to avoid an increase in the thickness of the vicinity of the bonded end portion 24 when the disposable diaper 1,1a,1b is worn, the portion of the absorbent body located between the folded position 240 of the bonded end portion 24 and the intermediate bonded portion 201 may be bonded to the turned-down portion of the bonded end portion 24 and the outer covering sheet.

The constituent elements of the above-described preferred embodiment and modified example may be appropriately combined with each other as long as they are not mutually exclusive,

while the present invention has been illustrated and described in detail, the foregoing description is in all aspects illustrative and not restrictive. It will, therefore, be understood that numerous modifications and variations can be devised without departing from the scope of the invention.

Description of the reference numerals

1,1a,1b disposable diaper

4,4b outer cover sheet

11 waist opening

12 leg opening

20,20a absorbent body

21 top sheet

22 absorbent core

23 rear sheet

24 bonding the end portions

25 (in the absorbent body) elastic member

34 side wall part

40 (of the outer covering sheet) inner surface

45,45a (in the outer covering sheet) elastic member

201 intermediate bonding part

221 (of the absorbent core) edge

240 folded position

241 (of bonded ends) edge

401 front part

402 middle part

403 rear part

Claims (7)

1. A pants-type disposable diaper having a waist opening at an upper end portion and a pair of leg openings at a lower portion, comprising:

an outer covering sheet folded at an intermediate portion between a front portion and a rear portion to be positioned on front and rear sides of a wearer, left and right end portions of the front portion being bonded to left and right end portions of the rear portion, respectively, to form waist openings at upper end portions of the front and rear portions and a pair of leg openings below the front and rear portions, the pair of leg openings being positioned on left and right sides of the intermediate portion; and

a sheet-like absorbent body having a top sheet, a back sheet and an absorbent core, the absorbent core being located between the top sheet and the back sheet, the absorbent body being attached to an inner surface of the outer covering sheet to contact the wearer and absorb excrement from the wearer, the absorbent body being arranged from the front portion to the back portion, the back sheet being located between an inner surface of the outer covering sheet and the absorbent core, the top sheet being located at an inner surface of the absorbent core; wherein the content of the first and second substances,

portions of the back sheet and the top sheet protruding from edges of the absorbent core in a longitudinal direction of the absorbent body, the portions being bonded to each other to form bonded end portions,

the bonded end portion of the absorbent body located at the front portion or the rear portion is folded toward the inner surface of the outer covering sheet so as to be bonded on the inner surface,

the entire edge of the bonded end portion of the absorbent body is located between the inner surface of the outer covering sheet and the other portion of the absorbent body, and

the absorbent body has an intermediate adhesive portion located at an intermediate portion in the longitudinal direction, and the intermediate adhesive portion is adhered to the inner surface of the outer covering sheet, and

a portion of the absorbent body, which is located between the folded position of the bonded end portion and the intermediate bonded portion, is not bonded to the bonded end portion and the outer covering sheet.

2. The disposable diaper of claim 1 wherein

The folded position of the bonded end overlaps the edge of the absorbent core or is located between the edge of the absorbent core and the waist opening.

3. The disposable diaper of claim 2 wherein

The entire edge of the bonded end portion of the absorbent body is located between the inner surface of the outer covering sheet and the absorbent core.

4. The disposable diaper of claim 2 wherein

The absorbent body further includes a pair of side wall parts that are located on left and right side portions of the absorbent body and stand upright from the top sheet, and

the pair of sidewall portions are bonded to the top sheet at the folded position.

5. The disposable diaper according to claim 1, wherein the other end portion of the absorbent body is folded toward the inner surface of the outer covering sheet so as to be bonded on the inner surface.

6. The disposable diaper according to claim 1, wherein the absorbent body has an approximately rectangular shape, and left and right corners of the bonded end portion of the absorbent body have chamfered shapes.

7. The disposable diaper according to any one of claims 1 to 6, further comprising

An elastic member that contracts the bonded end portion of the absorbent body in a width direction of the absorbent body to form a wrinkle in the bonded end portion.