JP2001252302A - Disposable diapers - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a disposable diaper having improved fit characteristics while maintaining the absorption performance of an absorbent core. SOLUTION: An elastic member 71a, 71b including a top sheet 2, a back sheet 3, an absorbent core 4, and an outer layer material 11 is provided in a circumferential direction around a torso portion A of the outer layer material 11 around a torso.
In the pants-type disposable diaper 1 where is arranged,
Absorbent core 4 and back sheet 3 or back sheet 3 and outer layer material 11 are partially joined and fixed, and at least the central part of abdominal part A where elastic members 71a and 71b are arranged. , The absorbent core 4 and the back sheet 3 or the back sheet 3 and the outer layer material 11 are not fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disposable diaper which is suitably used as a disposable diaper, especially for a baby, an adult or an incontinent person, and which has excellent fit and absorption performance.

[0002]

2. Description of the Related Art Pants-type disposable diapers are easy to put on and take off even when standing, and are used for toilet training for promoting the "diaper detachment" of infants. Alternatively, it is suitably used as a diaper for adults such as incontinent persons.

[0003] However, there is a limit in adaptability of the pants-type diaper to differences in body shape between wearers, and infants using the pants-type diaper are particularly intense in exercise.
There is a further need for improved fit. On the other hand, the improvement in the fitting property is one factor for deforming the absorbent core, and the absorbing performance may be greatly reduced depending on the manner of the deformation of the absorbent core. In particular, when an elastic member that crosses the absorbent core is arranged around the waist, or when the absorbent core is thin and lightweight and has high flexibility, the absorbent core is greatly deformed and the liquid in the absorbent core is deformed. Movement may be hindered.

[0004] Accordingly, an object of the present invention is to provide a disposable diaper having an improved fit while maintaining the absorption performance of the absorbent core. It is another object of the present invention to provide a disposable diaper having improved absorbability and improved fit even if the absorbent core is thin and flexible.

[0005]

SUMMARY OF THE INVENTION The present invention provides a liquid-permeable top sheet, a liquid-impermeable back sheet, a liquid-retentive absorbent core interposed between the two sheets, and a back sheet side. In a pants-type disposable diaper comprising an outer layer material arranged, and an elastic member arranged in a circumferential direction around a waist portion of a ventral side of the outer layer material, the absorbent core and the back sheet or the back sheet are provided. And the outer layer material are partially joined and fixed, and the absorbent core and the back sheet or the back sheet at least at the center of the abdominal side where the elastic member is disposed. The above object has been achieved by providing a pants-type disposable diaper to which the outer layer material and the outer layer material are not fixed (hereinafter, the first invention is referred to as this invention).

The present invention also provides a liquid-permeable top sheet, a liquid-impermeable back sheet, a liquid-retentive absorbent core interposed between the two sheets, and an outer layer material disposed on the back sheet side. In the deployable disposable diaper in which fastening tapes are respectively arranged on the left and right sides of the back side of the outer layer material, the absorbent core and the back sheet or the back sheet or the outer layer material, A deployable disposable diaper that is partially joined and fixed, and in which the absorbent core and the back sheet or the back sheet and the outer layer material are not fixed at least in the center of the abdominal part. The above object has been achieved by providing (hereinafter, referred to as the second invention).

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a preferred embodiment of the disposable diaper of the first invention will be specifically described with reference to the drawings. Here, FIG. 1 shows the first disposable diaper of the first invention.
FIG. 2A is a plan view of a state before assembling the disposable diaper shown in FIG. 1 as viewed from a top sheet side, and FIG. 2B is a plan view of FIG. It is bb sectional drawing.

The disposable diaper 1 of the present embodiment is of a pants type as shown in FIGS. 1 and 2, and has a liquid-permeable top sheet 2, a liquid-impermeable back sheet 3 and both sheets 2, 3.
A substantially vertically elongated absorbent body 10 having a liquid-retentive absorbent core 4 interposed therebetween, and an outer layer material 11 disposed on the backsheet 3 side of the absorbent body 10 are provided.

The diaper 1 has an abdominal part A disposed on the abdomen of the wearer, a dorsal part B disposed on the dorsal side, and a crotch C located therebetween. The side edges A1, A2 and the side edges B1, B2 of the back side B are joined to each other to form a waist opening 5 and a pair of leg openings 6.
For this bonding, for example, a heat seal, a high frequency seal, an ultrasonic seal, or the like is used.

The top sheet 2, the back sheet 3, and the absorbent core 4 are each rectangular and are integrated to form a vertically long absorbent body 10. The back sheet 3 is partially joined to the absorbent core 4 by predetermined joining means. This partial joining will be further described later. As the topsheet 2 and the leakproof sheet 3, the same as those conventionally used for this type of diaper can be used. The absorbent core 4 is composed of particles of a super absorbent polymer and a fiber material, and is covered with tissue paper (not shown).

As shown in FIG. 2, side cuffs 8, 8 made of a liquid-resistant or liquid-impermeable, air-permeable material are formed on both left and right sides in the longitudinal direction of the absorber main body 10. ing. Each side cuff 8 has a fixed end and a free end along the longitudinal direction of the absorber main body 10. The fixed end is fixed to the topsheet 2. On the other hand, in the vicinity of the free end, a side cuff elastic member 81 is arranged in an extended state. As a result, the side cuffs 8 stand up, thereby preventing the liquid from flowing out in the width direction of the absorber main body 10.

As shown in FIG. 2, the absorber main body 10 is fixed to the center of the outer layer material 11 with its longitudinal direction coinciding with the longitudinal direction of the outer layer material 11. This fixing will be further described later.

The outer layer material 11 includes at least two nonwoven fabrics,
That is, it has an outer nonwoven fabric 12 and an inner nonwoven fabric 13 disposed on the inner surface side of the outer nonwoven fabric 12. The outer layer material 11 forms the outer shape of the diaper 1, and the outer layer nonwoven fabric 12 constituting the outer layer material 11 forms the outer surface of the diaper 1, and the inner layer nonwoven fabric 13
Is bonded to the inner surface side of the outer nonwoven fabric 12 by an adhesive such as a hot melt adhesive. The outer layer material 11 has an hourglass shape in which both side edges are confined inward at the center in the longitudinal direction.

The outer layer material 11 extends outward from the front and rear edges of the absorber main body 11, and the extended portion is
It is folded back to one side. The front and rear edges of the folded outer layer material 11 are located on the absorbent core 4 in the absorber main body 11 as shown in FIG. 2B.

As shown in FIG. 2, a plurality of waist elastic members 51a and 51b are arranged at the front and rear ends of the outer layer material 11 along the front and rear edges along the width direction.
Each of the waist elastic members 51a and 51b is made of an outer nonwoven fabric 1
2 and the inner non-woven fabric 13 are sandwiched and fixed in an extended state. When the waist elastic members 51a and 51b are joined to each other, the two side edges A1 and A2 of the abdominal part A of the diaper 1 and the two side edges B1 and B2 of the back part B are joined together.
The ends of 1a and 51b are arranged so as to overlap each other.
Thus, a substantially continuous ring-shaped waist gather is formed near the waist opening 5 of the diaper 1, as shown in FIG.

As shown in FIG. 2, leg-side elastic members 61a, 61b
Is arranged. Each leg elastic member 61a, 61b
Is composed of a central portion 61a ', 61b' and each side edge portion 61a ", 61b" continuous therewith. The center portions 61a 'and 61b' are arranged so as to cross the crotch portion of the diaper 1, and the side edge portions 61a "and 61b" are arranged along the curved portion. Each leg elastic member 61a, 61b is disposed between the outer nonwoven fabric 12 and the inner nonwoven fabric 13, and the side edge portions 61a ″, 61b ″ of the elastic members 61a, 61b are fixed to each other by a predetermined joining means. It is fixed to the nonwoven fabrics 12 and 13 in an extended state. Each of the leg elastic members 61a and 61b includes both side edges A1 and A2 of the abdominal portion A of the diaper 1 and both side edges B1 and B1 of the back portion B.
B2 and the two elastic members 61a,
61b are arranged so that the ends thereof overlap. Thereby, as shown in FIG. 1, substantially continuous ring-shaped leg gathers are formed near the leg openings 6, 6 of the diaper 1.

As shown in FIG. 2, a torso peripheral portion D located between the front and rear end portions of the outer layer material 11 and the curved portions on both the left and right sides.
, A plurality of waist peripheral elastic members 71a, 71b are arranged in the width direction of the outer layer material 11, respectively. Each of the waist peripheral elastic members 71a and 71b is arranged so as to cross the absorbent core 4 at the abdominal part A and the dorsal part B of the diaper 1, and is extended by the outer nonwoven fabric 12 and the inner nonwoven fabric 13. It is pinched and fixed. Each of the elastic members 71a, 71b of the waist peripheral portion is formed by joining both side edges A1, A2 of the abdominal portion A of the diaper 1 and both side edges B1, B2 of the back side portion B with each other. Are arranged such that their ends overlap. Thereby, as shown in FIG. 1, the abdominal part A and the back part of the diaper 1 (not shown).
The waist gathers are formed at the waist circumference D of the diaper 1, respectively, and both gathers are substantially continuously formed in a ring shape around the waist circumference of the diaper 1.

The waist elastic member 51, the leg elastic member 61, the waist elastic member 71 and the side cuff elastic member 8
As 1, those obtained by forming a natural rubber, a polyurethane resin, a urethane foam resin, or the like into a belt shape or a thread shape are preferably used. The waist elastic member 51 and the leg elastic member 61 each preferably have a stress at 30% elongation of 10 to 50 gf, and an elongation ratio of 60 to 1
It is preferable that the nonwoven fabric is sandwiched and fixed between the outer nonwoven fabric 12 and the inner nonwoven fabric 13 in a state of 60%. The expansion rate is
It is the ratio of the length that has been increased by stretching to the natural length. For example, if the length is increased from 10 cm to 20 cm, the stretching ratio is set to 100%.

The torso elastic members 71a and 71b described above.
The absorbent core 4 in the central part of the abdominal part A and the back part B of the diaper 1 may be contracted and deformed in the width direction due to the contraction of the diaper 1, and the absorbing performance may be reduced. In particular, when the back sheet 3 enters the absorbent core 4 due to the shrinkage deformation of the absorbent core 4, the deformation of the absorbent core 4 is promoted, and the movement of the liquid in the absorbent core 4 is hindered. There is a possibility that the performance will be further reduced. To prevent this,
In the diaper 1 of the present embodiment, the absorbent core 4 and the back sheet 3 are partially joined and fixed, and at least the central part of the abdominal part A where the waist peripheral elastic member 71a is disposed. The absorbent core 4 and the back sheet 3 are not fixed to each other. At the same time, the back sheet 3
The entire surface is bonded and fixed to the outer layer material 11.

These joining states will be further described with reference to FIG. FIG. 3 is an exploded perspective view showing a joint state and the like of the back sheet 3 and the outer layer material 11 in the absorber main body. As shown in FIG.
Are fixedly joined to an absorbent core (not shown) in the left and right side edges 3a, 3a and in a region 3b corresponding to the crotch of the diaper 1. An adhesive means such as a hot melt adhesive is used for the bonding and fixing. The other area of the back sheet 3 is not fixed to the absorbent core 4. That is, the abdominal part A and the back part B of the diaper 1 on which the waist circumference elastic members 71a and 71b are respectively arranged.
At least at the central portion, in particular, the waist-surrounding elastic members 71a, 71
Ventral part A and dorsal part B, each crossing the absorbent core
In at least the central part, the absorbent core 4 and the back sheet 3 are not fixed to each other. Further, as described above, the back sheet 3 is provided over the entire surface thereof in the bonding region 11a.
Is fixedly joined to the outer layer material 11. As a bonding and fixing means between the back sheet 3 and the outer layer material 11, for example, an adhesive means such as a hot melt adhesive is used.

The absorbent core 4, the back sheet 3, and the outer layer material 1
1 is in such a fixed state, the absorbent core 4 due to shrinkage of the waist peripheral elastic members 71a and 71b.
This effectively prevents the shrinkage deformation of the material and the resulting decrease in absorption performance. In the crotch part C of the diaper 1, these three parts are integrated, and the contraction deformation of the absorbent core 4 due to the contraction of the leg elastic members 61a and 61b and the reduction of the absorption performance caused by the contraction are effectively prevented. In particular, the diaper 1 in which the waist circumference elastic members 71a and 71b are respectively arranged.
In at least the central part of the abdominal part A and the back part B, only the back sheet 3 and the outer layer material 11 are integrated,
Since the absorbent core 4 and the back sheet 3 are not fixed, the back sheet 3 is prevented from entering the absorbent core 4 even if the absorbent core 4 is twisted. As a result, liquid movement in the absorbent core 4 is not hindered. Furthermore,
Even if the back sheet 3 is deformed, it does not directly affect the absorbent core 4.

Left and right side edges 3a of the back sheet 3
The joining region 3a extends over the entire region in the longitudinal direction and has a band shape having a predetermined width. This joining region may be continuous or discontinuous. The width of this joining area is
Improve the texture (softness) of the whole product and absorb core 4
2 to 30 m from the viewpoint of improving the adhesion between
m, particularly preferably 3 to 10 mm.

The joining area of the area 3b corresponding to the crotch part of the diaper 1 in the back sheet 3 has a rectangular shape.
This rectangular joint region is formed by the leg elastic members 61a and 61a.
1b, the central portion 61 across the diaper crotch
The crossing by the a ', 61b' is preferable in that the contraction deformation of the absorbent core 4 due to the contraction of the leg elastic members 61a, 61b is effectively prevented. This rectangular joining region has a length of 30 to 150 mm, especially 50
~ 120mm, width 30 ~ 150mm, especially 50 ~ 1
The diameter of 20 mm is preferable from the viewpoints of preventing a decrease in absorption performance due to the fact that the absorbent core 4 is easily twisted, preventing a decrease in fit of the diaper 1, and preventing a decrease in the feel of the outer layer material 11.

The area of the joining area between the absorbent core 4 and the back sheet 3 is 5 to 60 times the area of the absorbent core 4 in plan view.
%, Particularly 15 to 35%, from the viewpoint that the liquid movement in the absorbent core 4 becomes smooth. Further, when the area of the bonding area between the absorbent core 4 and the back sheet 3 is a and the area of the bonding area between the back sheet 3 and the outer layer material is b,
The ratio a / b of both is 1/5 to 1 / 1.5, especially 1/4 to 1
When the absorbent core 4 is deformed, the back sheet 3 is effectively prevented from entering the core 4, and the back sheet 3 and the outer layer material 11 are integrated with each other. This is preferable because the liquid movement in the absorbent core 4 is hardly hindered.

The prevention of the deformation of the absorbent core 4 is as follows.
This is particularly effective when the absorbent core 4 is thin and lightweight and has high flexibility. Specifically, the thickness of the absorbent core 10 is 0.5 to 1
0 mm, especially about 0.5 to 5 mm, when the content of pulp fibers in the absorbent core 4 is 0 to 55% by weight, particularly about 0 to 30% by weight, or when the absorbent core 4
The value of Taber stiffness, which is a measure of flexibility, is 0.5 to
In the case of 20 gf · cm, particularly 1 to 10 gf · cm, the absorbability of the absorbent core 4 is particularly high, but the absorbent core 4 is easily deformed. However, since the absorbent core 4 and the back sheet 3 are fixed by partial joining as described above, even when the thin and lightweight absorbent core 4 that is easily deformed is used, the deformation is effective. Is prevented. When the content of the pulp fiber in the absorbent core 4 is 0 to 55% by weight, the content of the superabsorbent polymer is preferably 40 to 100% by weight, particularly preferably 50 to 100% by weight. The content of the fiber material other than the fiber (for example, the heat-fusible fiber) is 0.1 to 7% by weight, particularly 1%.
It is preferably about 5% by weight.

The Taber stiffness described above is measured by a stiffness test method (JIS P 8) using a paperboard Taber stiffness tester.
125). Specifically, the absorptive core 4 is cut into 3.8 × 7.0 cm together with the tissue paper wrapping it, and the measurement is performed using a Taber stiffness tester.

Next, the second embodiment of the first invention and the second embodiment
A first embodiment of the invention will be described. In these embodiments, only the points different from the above-described embodiment will be described, and the same points will not be particularly described. However, the detailed description of the above-described embodiment is appropriately applied.

In the second embodiment, the waist-side elastic members 71a and 71b in the abdominal part A and the dorsal part B are
Elastic elasticity is developed in a portion where the absorbent core 4 is not present, and in the portion where the absorbent core 4 is present, the elasticity is substantially not expressed and a gather is formed. Not. Here, "substantially no elastic elasticity is exhibited" means that the elastic elasticity is reduced to such an extent that gathers are not formed even in a state where the elastic elasticity is originally developed. means. This also includes the case where the elastic body is arranged on the absorbent core in a non-extended state, and the case where the elastic body is not arranged at all.

More specifically, in the diaper according to the present embodiment, the outer layer material located at the portion where the absorbent core 4 exists is subjected to a heat treatment to improve rigidity so that gathers are not formed. I have. Specifically, the waist peripheral elastic members 71a and 71b are fixed by a predetermined joining means at a portion where the absorbent core 4 does not exist, but are heated and heated at a portion where the absorbent core 4 exists. Pressure treatment is applied and fixed. By performing the heating and pressurizing treatment, the waist circumference elastic members 71a and 71b in the region where the absorbent core 4 exists are partially cut, and the waist circumference elastic member in the region where the absorbent core 4 exists. The contraction stress of 71a, 71b is reduced. By fixing the waist periphery elastic members 71a and 71b in this manner, the deformation of the absorbent core 4 is further prevented, and the deterioration of the absorption performance is further suppressed.

The first embodiment of the second invention relates to a deployable disposable diaper. The form of this diaper is substantially the same as the diaper shown in FIG. 2 described with respect to the first embodiment of the first invention. The different points are that fastening tapes are arranged on both left and right sides on the back side of the outer layer material, the waist circumference elastic members 71a and 71b are not arranged, and the surface of the outer layer material on the belly side is The point is that the fastener of the fastening tape is provided. And in the diaper of this embodiment, the absorbent core and the back sheet or the back sheet and the outer layer material are fixed by partial joining, and at least at the center of the abdominal part, the absorbent core and the back sheet are fixed. The sheet or the back sheet and the outer layer material are not fixed to each other. In the diaper of such an embodiment, the same effect as that of the diaper of the first invention can be obtained.

The present invention is not limited to the above embodiment. For example, in the embodiment, the absorbent core and the back sheet are fixed by partial joining, and the absorbent core and the back sheet are not fixed to each other at the center of the abdominal part, Alternatively, the back sheet and the outer layer material may be partially joined and fixed, and the back sheet and the outer layer material may be unfixed to each other at the center of the abdomen. In this case, there is no particular limitation on the joining state between the absorbent core and the back sheet, and the absorbent core may be joined over the entire surface or may be partially joined.

In each of the above embodiments, the absorbent core 4 and the back sheet 3 or the back sheet 3 and the outer layer material 11 are not fixed to each other on both the abdominal part A and the back part B of the diaper 1. However, instead of this, the absorbent core 4 and the back sheet 3 or the back sheet 3
The outer layer material 11 and the outer layer material 11 may be fixed to each other.

Further, in each of the above embodiments, the waist peripheral elastic members 71a and 71b are arranged so as to cross over the absorbent core 4, but the length of the absorbent core 4 in the longitudinal direction is reduced. Or by disposing the absorbent core 4 so as to be deviated toward the abdominal part A side or the dorsal part B side, even if the waist circumference elastic members 71a, 71b are arranged so as not to cross the absorbent core 4. good.

[0034]

According to the disposable diaper of the present invention, the absorbability of the absorbent core is maintained while the fit is improved. Further, according to the disposable diaper of the present invention, even if the absorbent core is thin and flexible, the absorbability is maintained and the fit is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a disposable diaper of the first invention.

FIG. 2A is a plan view of a state before assembling the disposable diaper shown in FIG.
FIG. 2B is a cross-sectional view taken along the line bb in FIG.

FIG. 3 is an exploded perspective view showing an adhesion state and the like between a back sheet and an outer layer material in the absorbent body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Disposable diaper 2 Top sheet 3 Back sheet 4 Absorbent core 10 Absorber main body 71a, 71b Torso peripheral elastic member A Abdominal part B Back side part C Inseam part D Torso peripheral part

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tohru Hayase 2606 Kabane-cho, Akaga-cho, Haga-gun, Tochigi Pref. In the Kao Co., Ltd. Terms (reference) 3B029 BA12 BA18 BC02 BD09 BD10 BD12 BD13 BD15 4C098 AA09 CC03 CC12 CC14 CE05 DD06 DD23

Claims (8)

[Claims] A liquid-permeable topsheet, a liquid-impermeable backsheet, a liquid-retentive absorbent core interposed between the two sheets, and an outer layer material disposed on the backsheet side; In a pants-type disposable diaper in which an elastic member is arranged in a circumferential direction at a waist circumference of a ventral side of the outer layer material, the absorbent core and the back sheet or the back sheet and the outer layer material are partially The absorptive core and the back sheet or the back sheet or the outer layer material are fixed at least at a central portion of the abdominal side where the elastic member is disposed. Not a pants-type disposable diaper. 2. The elastic member is disposed around the abdomen of the outer layer material so as to cross over the absorbent core, and the elastic member crosses the absorbent core. The disposable diaper according to claim 1, wherein the absorbent core and the back sheet or the back sheet and the outer layer material are not fixed at least in a central portion of the portion. 3. The absorbent core is fixedly joined to the back sheet in regions corresponding to left and right side edges and a diaper crotch, and the back sheet is joined to the outer layer material over the entire surface thereof. The disposable diaper according to claim 1 or 2, which is fixed. 4. A ratio a / b of a joining area area a between the absorbent core and the back sheet to a joining area area b between the back sheet and the outer layer material is 1/5 to 1 / 1.5. The disposable diaper according to claim 3, wherein 5. The absorbent core has a thickness of 0.5 to 10 m.
5. The absorbent core according to claim 1, wherein the absorbent core is composed of a super absorbent polymer and a fiber material, and the content of the pulp fiber in the absorbent core is 0 to 55% by weight. Disposable diapers. 6. A bonding area where the absorbent core is fixedly connected to the back sheet in a region corresponding to a crotch portion of the diaper, has a length of 30 to 150 mm and a width of 30 to 150 mm.
mm, and an elastic member is disposed in the leg opening of the diaper. The elastic member is disposed along the leg opening, and is continuous with the portion and crosses the diaper crotch. The disposable diaper according to claim 3, wherein the portion of the elastic member that crosses the crotch portion of the diaper crosses the rectangular joining region. 5. 7. The elastic member disposed around the waist portion exhibits elastic elasticity in a portion where the absorbent core does not exist, and substantially elastically expands and contracts in a portion where the absorbent core exists. The disposable diaper according to any one of claims 1 to 6, wherein the disposable diaper is arranged so as not to exhibit a property and not to form gathers. 8. A liquid-permeable topsheet, a liquid-impermeable backsheet, a liquid-retentive absorbent core interposed between the two sheets, and an outer layer material disposed on the backsheet side. In a deployable disposable diaper in which fastening tapes are respectively disposed on left and right sides of a back side of the outer layer material, the absorbent core and the back sheet or the back sheet or the outer layer material are partially Is an unfolded disposable diaper which is fixed by bonding, and wherein the absorbent core and the back sheet or the back sheet and the outer layer material are not fixed at least at the center of the abdominal side.