HK1177676B - Disposable diaper - Google Patents

Abstract

A pants-type disposable diaper has an outer covering sheet formed of a nonwoven fabric. An absorbent body is attached on the outer covering sheet to absorb excrement from the wearer. Sheet members are bonded, (also called "end sheets" or "end holding sheets") on the front and back, each end portion of the absorbent body being positioned and fixed between the sheet member and the outer covering sheet. The sheet member may be a laminated sheet of plastic film and nonwoven fabric, stretching of the sheet member is suppressed and it is possible to easily bring the absorbent body in close contact with the crotch region of the wearer when putting the disposable diaper on the wearer. The sheet member may also be formed of nonwoven fabric, a fiber orientation of nonwoven fabric on the sheet member then being orthogonal to the edges of end portions of the outer covering sheet in the longitudinal direction, to suppress longitudinal streching of the sheet member.

Description

Disposable diaper having a disposable diaper

Technical Field

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

Background

A pants-type disposable diaper having a waist opening at an upper end portion and a pair of leg openings on a lower portion is generally used as one type of absorbent article 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 disposed 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 placed from the front portion to the rear portion.

In japanese patent application laid-open No. 2007-979797979, a pair of end holding sheets is disclosed which are bonded to the front and rear portions to cover both end portions of the absorbent body in the longitudinal direction, respectively, and the absorbent body is firmly fixed on the outer covering sheet by the end holding sheets.

Recently, the comfort level of wearing disposable diapers is gradually improved by thinning and softening of the outer covering sheet made of nonwoven fabric, however, the outer covering sheet of such disposable diapers is easily stretched. Therefore, when this disposable diaper is put on the wearer, even if the front and rear portions are pulled up to bring the absorbent body into close contact with the crotch region of the wearer, the absorbent body itself is not easily pulled up because of the extension of the outer covering sheet. When the absorbent body is not in close contact with the crotch region of the wearer, there may be cases where: the excrement cannot be properly absorbed into the absorbent body and leaks to the outside.

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. An object of the present invention is to easily urge an absorbent body into close contact with a crotch region of a wearer when a disposable diaper is put on the wearer.

A preferred disposable diaper according to the present invention comprises: an outer covering sheet folded at an intermediate portion between a front portion and a rear portion to be disposed on a front side and a rear side 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 a waist opening at upper end portions of the front portion and the rear portion and a pair of leg openings below the front portion and the rear portion, the pair of leg openings being located on left and right sides of the intermediate portion; an absorbent body attached to the outer covering sheet to absorb excrement from the wearer, the absorbent body being arranged from the front portion to the rear portion; and a sheet member that extends along an edge of an upper end portion of one of the front portion and the rear portion, and that is bonded on an inner surface of the outer covering sheet in the one portion, one end portion of the absorbent body being fixed between the sheet member and the outer covering sheet; wherein the outer covering sheet is formed of a nonwoven fabric, the sheet member is a laminated sheet of a plastic film and a nonwoven fabric, and a surface of the sheet member facing the wearer is a surface of the nonwoven fabric. Therefore, when the disposable diaper is put on the wearer, the absorbent body can be easily brought into close contact with the crotch region of the wearer. Further, it is possible to prevent moisture of excrement from leaking to the outside through the sheet member.

Another preferred disposable diaper according to the present invention comprises: an outer covering sheet folded at an intermediate portion between a front portion and a rear portion to be disposed on a front side and a rear side 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 a waist opening at upper end portions of the front portion and the rear portion and a pair of leg openings below the front portion and the rear portion, the pair of leg openings being located on left and right sides of the intermediate portion; an absorbent body attached to the outer covering sheet to absorb excrement from the wearer, the absorbent body being arranged from the front portion to the rear portion; and a sheet member that extends along an edge of an upper end portion of one of the front portion and the rear portion, and that is bonded on an inner surface of the outer covering sheet in the one portion, one end portion of the absorbent body being fixed between the sheet member and the outer covering sheet; wherein the outer covering sheet and the sheet member are formed of a nonwoven fabric, fibers of the nonwoven fabric in the sheet member being oriented perpendicularly to an edge of the upper end portion. Therefore, when the disposable diaper is put on the wearer, the absorbent body can be easily brought into close contact with the crotch region of the wearer.

According to an aspect of the present invention, since the entire surface of the sheet member is bonded to the outer covering sheet and the absorbent body, it is easier to bring the absorbent body into close contact with the crotch region of the wearer.

According to another aspect of the present invention, the disposable diaper further comprises another sheet member having the same structure as the sheet member, wherein the sheet member and the other sheet member are arranged to the front portion and the rear portion, respectively. This makes it easier to urge the absorbent body into close contact with the crotch region of the wearer.

In this case, when the sheet member can be distinguished from another sheet member, the front and rear portions of the disposable diaper can be easily identified.

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 according to a first preferred embodiment.

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

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

Fig. 4 is a sectional view of the sheet member.

Fig. 5 is a view showing a disposable diaper according to a comparative example.

Fig. 6 is a plan view of a disposable diaper according to a second preferred embodiment.

Fig. 7 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 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 which has a waist opening 11 at an upper end portion (which is an end portion on the upper side of fig. 1) and a pair of leg openings 12 at a lower portion, and which receives excrement from a wearer.

Fig. 2 is a plan view of the disposable diaper 1 in a state where the disposable diaper 1 is unfolded, and in fig. 2, the disposable diaper 1 is viewed from the wearer's side. As shown in fig. 2, the disposable diaper 1 has: an outer covering sheet 4; a sheet-like absorbent body (absorber) 20 attached on an inner surface (i.e., a wearer-facing surface) of the outer covering sheet 4 to absorb excrement from a wearer; and two sheet members 5 (which are also referred to as "end sheets" or "end holding sheets") which are bonded on the outer covering sheet 4 so as to cover both end portions of the absorbent body 20 in the longitudinal direction (i.e., the up-down direction in fig. 2). Each sheet member 5 is provided so as to span almost the entire width of the outer covering sheet 4 with respect to the left-right direction (lateral direction) in fig. 2. Hereinafter, the left-right direction in fig. 2 is referred to as "the width direction of the diaper".

In the disposable diaper 1, the upper part in fig. 2 is to be disposed (covered) on the front side (ventral side) of the wearer, and the lower part in fig. 2 is to be disposed on the rear side of the wearer. In the following description, portions of the disposable diaper 1 (and portions of the outer covering sheet 4) disposed on the front and rear sides of the wearer are referred to as "front portion 401" and "rear portion 403", respectively, and a portion facing the crotch region of the wearer at a position between the front portion 401 and the rear portion 403 is referred to as "middle portion 402". The middle portion 402 is continuous with the front portion 401 and the rear portion 403.

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 thermal bonding (heat sealing) under heat and pressure. As above, since both side end portions of the front portion 401 are bonded to both side end portions of the rear portion 403, respectively, 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 on the left and right sides of the middle portion 402 are formed below the front portion 401 and the rear portion 403. Hereinafter, the vertical direction in fig. 1 (the direction is not limited to the direction of gravity) is referred to as "vertical direction of the diaper".

Fig. 3 is a sectional view (cross-section at the intermediate portion 402) of the disposable diaper 1 taken along the line III-III in fig. 2. 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. 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 width direction of the diaper), and the pair of side sheets 3 extends across almost the entire length of the main body portion 2 in the longitudinal direction. As shown in fig. 3, the main body portion 2 has a top sheet 21, a back sheet 23, and an absorbent core 22, which 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 a thick dashed line in fig. 2 in order 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 intermediate 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 band-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 in the longitudinal direction across almost the entire length of the side sheet, and the adhesive 33 is arranged 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, it spans almost the entire length of the main body portion in the longitudinal direction, and it is adhered on the upper side (i.e., the wearer's side) of the main body portion 2 by hot melt adhesive.

The side wall portion 34 is continuous from the bonded portion 33 by a fold line 39. In both end portions thereof in the longitudinal direction, the side wall portions 34 are placed 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 on 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 a standing portion 342 standing upward from the main body portion 2 at an intermediate portion thereof 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 (gathers) are formed in the standing portion 342 by contraction of the elastic member 35.

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 leg gathers are formed. Further, by contraction of the waist elastic member 44, a waist gather is formed. Of the plurality of waist elastic members 44, several waist elastic members 44 are located near the edges of the waist opening 11 (see fig. 1) and are densely arranged, and the disposable diaper 1 is tightly fitted around the waist of the wearer by these waist elastic members 44.

In each of the front part 401 and the rear part 403 in fig. 2, the above sheet member 5 is bonded on the outer covering sheet 4 (the inner sheet 41 of the outer covering sheet 4) by hot melt adhesive or the like. The sheet member 5 extends along the edge of the upper end of the disposable diaper 1 (i.e., the edge is the edge of both end portions of the outer covering sheet 4 in the longitudinal direction). In the present embodiment, the sheet member 5 is rectangular. When bonding the sheet member 5, a hot melt adhesive is applied to the entire area by a water curtain spray gun (water spray gun) or a coater to overlap the sheet member 5 on the outer covering sheet 4, and thus almost the entire area of the sheet member 5 is bonded on the inner surface of the outer covering sheet 4. In practice, the absorbent body 20 has been bonded to the outer covering sheet 4 when it is placed from the front portion 401 to the rear portion 403. In this way, each end portion of the absorbent body 20 is disposed (sandwiched) between the sheet member 5 and the exterior covering sheet 4, and thus the absorbent body 20 is firmly fixed on the exterior covering sheet 4.

In the disposable diaper 1, the color of the sheet member 5 bonded on the front portion 401 is different from the color of the sheet member 5 bonded on the rear portion 403. Since the outer covering sheet 4 is thin, the color of each sheet member 5 is transmitted through the outer covering sheet 4 and can be easily visually recognized when the disposable diaper 1 is viewed from the outside.

The top sheet 21 is made of a liquid-permeable sheet material, and the top sheet 21 immediately captures moisture from excrement of 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 used for the top sheet 21 are point-bonded nonwoven fabrics (point-bond nonwoven fabrics), air-permeable nonwoven fabrics, and spun-bonded nonwoven fabrics (spunbond fabrics). A nonwoven fabric (e.g., spunlace nonwoven fabric) made of hydrophilic fibers such as cellulose, rayon, cotton may be used as the top sheet 21.

The absorbent core 22 is formed by coating a mixture of hydrophilic fibers such as pulped fibers or cellulose fibers and super absorbent materials such as granular super absorbent polymers (e.g., SAP (super absorbent polymer)) or super absorbent fibers in tissue paper (tissue paper), liquid-permeable nonwoven fabric, or the like, and the absorbent core 22 rapidly absorbs and retains moisture that has passed through the top sheet 21. A tissue, a liquid-permeable nonwoven fabric, or the like used to coat 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 falling off of the absorbent material (in particular, falling off after absorbing moisture). In the present embodiment, the absorbent core 22 includes pulp fibers and SAP.

Used as the back sheet 23 is a water-repellent 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 water-repellent or liquid-impermeable plastic film. The backsheet 23 prevents moisture of excrement or the like that has reached the backsheet 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, it is preferable to use a plastic film having permeability (breathability) from the viewpoint of preventing perspiration in the disposable diaper 1 and providing a comfortable feeling to the wearer.

Used as the sheet main body of the side sheet 3 is a water-repellent 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, a band-like polyurethane film, yarn-like or band-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.

Used as the inner sheet 41 and the outer sheet 42 of the outer covering sheet 4 are water-repellent or liquid-impermeable nonwoven fabrics made of hydrophobic fibers in a manner similar to the back sheet 23. 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. As described above, the outer covering sheet 4 is formed of a nonwoven fabric in the disposable diaper 1.

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

Fig. 4 is a sectional view of the sheet member 5. The sheet member 5 is a laminated sheet (laminated body) including a layer 51 formed of a plastic film and a layer 52 formed of a nonwoven fabric, and the inner surface of the sheet member 5 facing the wearer (i.e., the surface of the layer 52 which is not bonded to the outer covering sheet 4) is the surface of the nonwoven fabric. Used as the layer 52 is a water-repellent or liquid-impermeable nonwoven fabric made of hydrophobic fibers in a manner similar to the outer covering sheet 4 and the back sheet 23, or a nonwoven fabric made of hydrophilic fibers or a liquid-permeable nonwoven fabric made of hydrophobic fibers (in which hydrophilic treatment is performed) in a manner similar to the top sheet 21. A water-proof or liquid-impermeable plastic film is used as the layer 51. Preferably, a plastic film having permeability (breathability) is used.

When the disposable diaper 1 shown in fig. 1 is worn on a wearer, both legs of the wearer are inserted into a pair of leg openings 12 through the waist opening 11, and then the disposable diaper 1 is grasped at edge portions around the waist opening 11 and pulled up so as to surround the waist of the wearer. At this time, the front portion 401 is pulled up (toward the head of the wearer) together with one sheet member 5, and the rear portion 403 is also pulled up together with the other sheet member 5. Thus, each end portion of the absorbent body 20 is pulled up so that the absorbent body 20 is brought into close contact with the crotch region of the wearer.

Fig. 5 is a view showing a disposable diaper 9 according to a comparative example, and fig. 5 corresponds to fig. 2. In the disposable diaper 9 of the comparative example, each sheet member 91 is formed of only a nonwoven fabric. On the other hand, in the nonwoven fabric roll for manufacturing the sheet member 91, the fiber orientation (i.e., the fiber orientation is the direction in which the rigidity (strength required for deformation) of the nonwoven fabric is the largest, and the fiber orientation is also the direction in which the stretchability is the lowest) is the same as the withdrawal direction (i.e., the sheet withdrawal direction), and the fiber orientation of the nonwoven fabric is parallel to the width direction of the diaper (the left-right direction in fig. 5) in the sheet member 91, so as to simplify the manufacturing of the disposable diaper 9 of the comparative example. In the nonwoven fabric, since the stretchability is highest in the direction almost perpendicular to the fiber orientation, the sheet member 91 of the comparative example is easily stretchable in the up-down direction of the diaper perpendicular to the diaper width direction. The parallel lines (each line extending in the left-right direction) drawn in fig. 5 at the sheet member 91 show that the fiber orientation of the nonwoven fabric forming the sheet member 91 is parallel to the width direction of the diaper. In fact, the fiber orientation of the nonwoven fabric in the outer covering sheet 93 is also parallel to the width direction of the diaper.

When the sheet member 91 is bonded to the outer covering sheet 93, a hot melt adhesive is applied in the form of a plurality of lines parallel to the width direction of the diaper on the outer covering sheet 93 (as shown by thick broken lines indicated by reference numeral 94 in fig. 5), and then the sheet member 91 is placed and bonded on the outer covering sheet 93. In the disposable diaper 9 of the comparative example described above, the sheet member 91 is easily stretched in the diaper up-down direction together with the outer covering sheet 93. Therefore, when the disposable diaper 9 is put on the wearer, even if the front portion 931 and the rear portion 932 of the outer covering sheet 93 are pulled up together with the sheet member 91 so as to bring the absorbent body 92 into close contact with the crotch region of the wearer, the absorbent body 92 itself is not easily pulled up due to the stretching of the outer covering sheet 93 and the sheet member 91. Further, when moisture of excrement adheres to the inner surface of the sheet member 91, there may be the following cases: moisture of excrement passes through the sheet member 91 and the outer covering sheet 93 due to body pressure to leak out of the outer side of the outer covering sheet 93.

Correspondingly, in the disposable diaper 1 of fig. 2, since each sheet member 5 is a laminated sheet of a plastic film and a nonwoven fabric, even if the fibers of the nonwoven fabric of the sheet member 5 are oriented parallel to the width direction of the diaper, stretching of the sheet member 5 is suppressed. Therefore, when the disposable diaper 1 is put on the wearer, it is possible to surely pull up both end portions of the absorbent body 20 and easily bring the absorbent body 20 into close contact with the crotch region of the wearer (i.e., to urge both side end portions of the absorbent body 20 to fit into the groin of the wearer). Further, even if moisture of excrement adheres to the inner surface of the sheet member 5, it is possible to prevent the moisture of excrement from leaking out of the outer covering sheet 4 through the sheet member 5.

In the disposable diaper 1, the entire surface of the sheet member 5 is bonded to the outer covering sheet 4 (and the absorbent body 20) to integrate the sheet member 5 and the outer covering sheet 4. This makes it more difficult to cause stretching of the sheet member 5 and makes it easier to bring the absorbent body 20 into close contact with the crotch region of the wearer. Further, since the color of the sheet member 5 disposed in the front portion 401 is different from the color of the sheet member 5 disposed in the rear portion 403, the front and rear portions (front and rear) of the disposable diaper 1 can be easily identified.

Fig. 6 is a view showing a disposable diaper 1a according to a second preferred embodiment of the present invention, and fig. 6 corresponds to fig. 2. The disposable diaper 1a in fig. 6 differs from the disposable diaper 1 in fig. 2 in that the sheet member 5a is formed of only a nonwoven fabric. 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 each sheet member 5a in fig. 6, the fiber orientation of the nonwoven fabric is almost perpendicular to the waist elastic member 44, and the extensibility of the sheet member 5a is highest in the width direction of the diaper. In other words, in the disposable diaper 1a in which 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 (see fig. 1), respectively, the fiber direction of the nonwoven fabric is parallel to the longitudinal direction of the absorbent body 20, and the stretchability of the sheet member 5a is lowest in the up-down direction of the diaper. The parallel lines drawn in fig. 6 at the sheet member 5a (each line extending in the vertical direction (up-down direction)) show that the fiber orientation of the nonwoven fabric forming the sheet member 5a is parallel to the longitudinal direction of the absorbent body 20.

Each sheet member 5a has a belt-like shape which extends along an edge of an end portion of the front part 401 or the rear part 403 in a similar manner to the sheet member 5 shown in fig. 2, and the entire surface of the sheet member 5a is bonded to the inner surface of the outer covering sheet 4. In a manner similar to the disposable diaper 1, the color of the sheet member 5a on the front portion 401 is different from the color of the sheet member 5a on the rear portion 403. As above, the outer covering sheet 4 is formed of a nonwoven fabric.

Here, in the disposable diaper 9 of the comparative example shown in fig. 5, since the fiber orientation of the nonwoven fabric in the sheet member 91 is parallel to the width direction of the diaper, as has been described, when the disposable diaper 9 is put on the wearer, the sheet member 91 is easily stretched in the up-down direction of the diaper and it is difficult to pull up the absorbent body 92 so as to bring the absorbent body 92 into close contact with the crotch region of the wearer. Further, since the sheet member 91 is hardly stretched in the width direction of the diaper, there may be a case where: the disposable diaper 9 cannot be appropriately fitted (unfastened) around the waist of the wearer.

Correspondingly, in the disposable diaper 1a shown in fig. 6, since the fiber orientation of the nonwoven fabric in the sheet member 5a is perpendicular to the edge of the upper end portion of the disposable diaper 1 (i.e., the fiber orientation is in the up-down direction of the diaper), the sheet member 5a hardly stretches in the up-down direction of the diaper (i.e., it is difficult to cause the sheet member 5a to stretch in the up-down direction of the diaper). Therefore, when the disposable diaper 1a is put on the wearer, it is possible to surely pull up the end portion of the absorbent body 20 and easily bring the absorbent body 20 into close contact with the crotch region of the wearer.

Further, when the disposable diaper 1a is put on the wearer, the disposable diaper 1a is pulled up so as to surround the waist of the wearer along the fiber orientation of the nonwoven fabric in the sheet member 5 a. Therefore, when compared with the disposable diaper 9 of the comparative example, the feeling of the wearer's skin on the disposable diaper 1a in pulling up the disposable diaper 1a can be improved. Further, since the stretchability of the sheet member 5a is greatest in the width direction of the diaper, the disposable diaper 1a can be suitably fitted (fastened) around the waist of the wearer when compared with the disposable diaper 9 of the comparative example.

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

In the disposable diaper 1, 1a, the sheet member 5, 5a may be provided on only one of the front portion 401 and the rear portion 403. Also in this case, one end portion of the absorbent body 20 covered with the sheet member 5, 5a can be easily pulled up in the up-down direction of the diaper, and the absorbent body 20 can be easily urged into close contact with the crotch region of the wearer. In this case, there may be the following cases: in the disposable diaper 9 of the comparative example, the other end portion of the absorbent body 20 is covered with the sheet member 91, or the other end portion is not covered with any sheet member. From the viewpoint of more easily urging the absorbent body 20 into close contact with the crotch region of the wearer, it is preferable that two sheet members having the same structure as each other are arranged on the front portion 401 and the rear portion 403, respectively.

In the above first and second preferred embodiments, the entire surface of the sheet member 5, 5a is bonded to the outer covering sheet 4 by applying a hot melt adhesive by means of a water curtain spray gun or a coater. However, for example, as shown in fig. 7, there may be the following cases: the regions 61 in each of which the hot melt adhesive is applied in a straight line (a cross-sectional line is drawn at the region in fig. 7) and the regions 62 in each of which the hot melt adhesive is applied in a spiral form are alternately arranged in the up-down direction in fig. 7, and almost the entire surface of the sheet member 5 is bonded on the outer covering sheet 4 (the same applies to the sheet member 5 a). In each of the regions 62 in fig. 7, the hot melt adhesive is applied in two helical rows (which may be applied in one, three or more rows) extending in the width direction of the diaper. In the above disposable diaper, breathability and softness around the waist of the wearer are improved. In a manner similar to the disposable diaper 9 of the comparative example shown in fig. 5, there may be the following cases: the hot melt adhesive is applied on the outer covering sheet 4 so as to form a plurality of straight lines (or a plurality of spiral rows) which are parallel to the width direction of the diaper and are arranged at intervals in the up-down direction of the diaper, and thus the sheet members 5, 5a are bonded on the inner surface of the outer covering sheet 4. Also in this case, the absorbent body 20 can be easily urged into close contact with the crotch region of the wearer by the sheet members 5, 5a which hardly extend in the up-down direction of the diaper. In some designs of the disposable diapers 1, 1a, the sheet member 5, 5a may be bonded on the inner surface of the outer covering sheet 4 by applying a hot melt adhesive on the outer covering sheet 4 so as to form a plurality of lines parallel to the longitudinal direction of the absorbent body 20.

In the first and second preferred embodiments described above, since the color of the sheet member 5, 5a on the front portion 401 is different from the color of the sheet member 5, 5a on the back portion 403, the front portion 401 and the back portion 403 become distinguishable from each other in the disposable diaper. However, there may be the following: different characters, marks, patterns, and the like are formed on the sheet members 5, 5a on the front portion 401 and the sheet members 5, 5a on the rear portion 403, or characters, marks, patterns, and the like are formed only on one sheet member 5, 5a, and thus the sheet members 5, 5a on the front portion 401 and the sheet members 5, 5a on the rear portion 403 become visually distinguishable.

The constituent elements of the preferred embodiment and the modified example discussed above 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 may be devised without departing from the scope of the invention.

Description of the reference numerals

1. 1a Disposable diaper

4 outer covering sheet

5. 5a sheet member

11 waist opening

12 leg opening

20 absorbent body

51. 52 layers

401 front part

402 middle part

403 rear part

Claims (5)

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 disposed on a front side and a rear side 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 a waist opening at upper end portions of the front portion and the rear portion and a pair of leg openings below the front portion and the rear portion, the pair of leg openings being located on left and right sides of the intermediate portion;

an absorbent body attached to the outer covering sheet to absorb excrement from the wearer, the absorbent body being arranged from the front portion to the rear portion; and

a sheet member that extends along an edge of an upper end portion of one of the front portion and the rear portion, and that is bonded on an inner surface of the outer covering sheet in the one portion by an adhesive, one end portion of the absorbent body being fixed between the sheet member and the outer covering sheet, the adhesive being applied on the outer covering sheet so as to form a plurality of straight lines or a plurality of spiral rows that are parallel to the edge of the upper end portion and are arranged at intervals in a direction perpendicular to the edge of the upper end portion; wherein

The outer covering sheet is formed of a nonwoven fabric,

the sheet member is a laminated sheet of a nonwoven fabric and a plastic film for suppressing stretching of the sheet member, and the surface of the sheet member facing the wearer is a surface of the nonwoven fabric.

2. 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 disposed on a front side and a rear side 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 a waist opening at upper end portions of the front portion and the rear portion and a pair of leg openings below the front portion and the rear portion, the pair of leg openings being located on left and right sides of the intermediate portion;

an absorbent body attached to the outer covering sheet to absorb excrement from the wearer, the absorbent body being arranged from the front portion to the rear portion; and

a sheet member that extends along an edge of an upper end portion of one of the front portion and the rear portion, and that is bonded on an inner surface of the outer covering sheet in the one portion, one end portion of the absorbent body being fixed between the sheet member and the outer covering sheet; wherein

The outer covering sheet and the sheet member are formed of a nonwoven fabric,

the fibers of the nonwoven fabric in the sheet member are oriented perpendicular to the edge of the upper end portion.

3. The disposable diaper of claim 2 wherein

The entire surface of the sheet member is bonded to the outer covering sheet and the absorbent body.

4. The disposable diaper according to any one of claims 1 to 3, further comprising

Another sheet member having the same structure as the sheet member, wherein

The sheet member and the other sheet member are arranged to the front portion and the rear portion, respectively.

5. The disposable diaper of claim 4 wherein

The sheet member is distinguishable from the other sheet member.