JP7298059B2 - Absorbent article and its manufacturing method - Google Patents

Description

The present invention relates to absorbent articles and methods of manufacturing the same.

In recent years, the population of elderly people has increased, especially the number of bedridden care recipients has increased, and the labor shortage has become a serious problem in nursing care facilities. The number of regular changes of disposable diapers has been reduced from 5 to 7 times a day to 2 to 5 times per day. There is a demand for paper diapers that are resistant to rashes even when worn, and this is the first issue. In addition, in order to solve the labor shortage, the number of caregivers with little experience is increasing. A vicious cycle of increasing burdens has arisen. For care recipients with contractures, who are stiff with no gap between their legs, or when changing paper diapers in a dark place without changing their position as much as possible so as not to wake the care recipient while sleeping. In some cases, it is difficult to put the paper diaper through the gap between the crotch and make it adhere to the wearer's crotch.

In general, absorbent articles such as light incontinence pads, pants-type paper diapers, and tape-fastened paper diapers are composed of a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body disposed between the two sheets. , consists of As a result, body fluids such as urine pass through the top sheet and are absorbed by the absorbent member, and are prevented from leaking to the outside by the back sheet. Such absorbent articles have been devised in various ways in order to improve absorbency of bodily fluids, improve wearer's wearing comfort, prevent leakage, and the like.

JP 2015-112319 A JP 2017-063923 A

However, in Patent Document 1, a slit penetrating from the skin-contacting surface side to the non-skin-contacting surface side is provided, and the periphery of the slit has a structure that easily reverses. There is room for improvement in terms of the relationship between the position and size of the slit and the absorbent body, from the viewpoint of making the absorbent article more deformable and easier to wear. In addition, in Patent Document 2, by increasing the ratio of the superabsorbent polymer in the upper layer of the absorbent body, reversion around the upper layer slit is suppressed, but there is room for improvement in terms of wearability.

Therefore, in one aspect, an object of the present invention is to provide an absorbent article that diffuses and absorbs quickly, is easy to wear, has a dry feeling, suppresses leakage, and is suitable for long-term use such as at night in nursing care. and

The inventors of the present invention conducted extensive research in view of the above problems. As a result, the absorbent body is composed of at least two layered absorbent bodies, and the absorbent body is provided with slits interposed in pairs in the width direction extending in the longitudinal direction, so that the top sheet does not come into contact with the skin. The inventors have found that the above problems can be solved by an absorbent article provided with a perforated film on the surface side, and have completed the present invention. Specifically, the present invention provides the following.

(1) An absorbent article comprising a liquid-permeable topsheet, a liquid-impermeable backsheet, and an absorbent body disposed between the topsheet and the backsheet,
The total length of the absorbent body is 400 mm or more, and the absorbent body is provided in two upper and lower layers in a layered manner,
In the two-layer absorbent body, slits each having a length of 35% or more and 65% or less of the total length of the absorbent body penetrate in a width direction in pairs,
The absorber includes a crotch portion having a relatively narrow width arranged in the crotch portion of the wearer, an abdominal portion having a relatively wide width arranged on the abdominal side and the back side of the wearer, and a dorsal portion. and
the slit extends from the ventral portion through the crotch portion to the dorsal portion;
crotch width of the absorber is 140 mm or more and 160 mm or less;
the width of the abdominal portion of the absorber is 140 mm or more and 300 mm or less;
The width of the dorsal portion of the absorbent body is 200 mm or more and 330 mm or less,
In the crotch width of the absorber, the total width of the pair of slits is 7% or more and 25% or less of the crotch width of the absorber,
The pair of slits are contained within a range of 65% of the crotch width of the absorber from the center in the width direction of the absorber,
The pair of slits are provided at intervals of 15% or more of the crotch width of the absorber,
An absorbent article comprising an apertured film on the non-skin-contacting side of the top sheet.

(2) In the configuration of (1) above, the perforated film is a resin film, has a basis weight of 20 g/m 2 or more and 50 g/m 2 or less, and a thickness under no load of 0.6 mm or more. 0 mm or less, and the diameter of the opening is 0.45 mm or more and 0.98 mm or less.

(3) In the configuration of (2) above, in the perforated film, the distance between the perforations is 0.3 mm or more and 0.9 mm or less, and the area ratio of the perforations is 28% or more. % or less.

(4) A method for manufacturing an absorbent article having any one of the above (1) to (3),
A manufacturing method, wherein the lower layer of the absorbent body is formed from a raw material containing 30% or more and 70% or less of hardwood (eucalyptus) pulp.

In one aspect, according to the present invention, it is possible to provide an absorbent article that diffuses and absorbs quickly, is easy to wear, has a dry feeling, suppresses leakage, and is suitable for long-term use such as at night in nursing care. becomes.

1 is a plan view of an absorbent article according to an embodiment of the present invention, viewed from the top sheet side; FIG. 2 is a schematic cross-sectional view of the absorbent article along line BB in FIG. 1; FIG. FIG. 4 is a cross-sectional view for explaining an aperture;

Embodiments of the present invention are described in detail below, but they are given for the purpose of illustration and are not intended to limit the present invention. In addition, the same code|symbol is attached|subjected to the same element through the whole description of embodiment. Moreover, in the description of this specification, when the absorbent article 1 is worn means at least one of when the absorbent article 1 is worn and after the absorbent article 1 is worn. The longitudinal direction of the absorbent article 1 is the direction that spans the front and back of the wearer when the absorbent article 1 is worn, and is the direction indicated by symbol Y in the drawing. Moreover, the width direction of the absorbent article 1 is a direction that is transverse or perpendicular to the longitudinal direction, and is the direction indicated by symbol X in the drawing. Furthermore, the skin-contacting surface is the surface of the front and back surfaces of each member such as an absorbent body, which is arranged on the wearer's skin side when worn, and the non-skin-contacting surface is each member such as an absorbent body. Of the front and back sides of the , the side facing away from the wearer's skin when worn. Body fluids refer to liquids excreted from the body to the outside of the body, such as urine, blood, and water in loose stools. Further, examples of the absorbent article 1 include, but are not limited to, light incontinence pads, pants-type paper diapers, and tape-fastened paper diapers, regardless of whether they are for babies or adults. There may be.

[Absorbent article]
FIG. 1 is a plan view of an absorbent article 1 according to an embodiment of the present invention, viewed from the top sheet 20 side. FIG. 2 is a schematic cross-sectional view of absorbent article 1 along line BB in FIG. FIG. 2 is an illustration of the layered structure, the parts being shown very schematically.

As shown in FIG. 1, the absorbent article 1 includes a liquid-permeable topsheet 20 disposed on the skin-contacting side and a liquid-impermeable topsheet 20 disposed on the non-skin-contacting side facing the topsheet 20 . It comprises a permeable backsheet 21 (see FIG. 2), an absorbent body 30 positioned between the topsheet 20 and the backsheet 21 (not visible in FIG. 1), and an apertured film 40 . The absorbent body 30 is sandwiched between the top sheet 20 and the back sheet 21 in such a manner that the perforated film 40 is interposed between the top sheet 20 and the absorbent body 30 .

In order to prevent lateral leakage of bodily fluid excreted by the user, the absorbent article 1 has a pair of three-dimensional gather elastic members on the top sheet 20 along the longitudinal direction of the absorbent article 1 . Gathers may be provided (not shown). The outer ends of the three-dimensional gathers in the width direction of the absorbent article 1 are fixed to the back sheet 21, the inner ends are fixed to the top sheet 20, and the center is a free end that is not fixed to the top sheet 20. Gathered sheets are provided. By providing the three-dimensional gathers elastic member along the longitudinal direction, the three-dimensional gathers can stand upright and can be deformed according to the body shape of the wearer. As the three-dimensional gather elastic member, for example, a polyurethane thread, a strip-shaped polyurethane film, a thread-shaped or strip-shaped natural rubber, or the like is used. Nonwoven fabrics such as spunbond nonwoven fabrics, meltblown nonwoven fabrics, composite nonwoven fabrics obtained by laminating spunbond/meltblown/spunbond, and the like are used.

<Top sheet>
The top sheet 20 may be formed from a liquid-permeable base material that allows body fluids to move to the absorbent body 30. For example, non-woven fabrics such as air-through non-woven fabrics, thermal-bonded non-woven fabrics, spun-bonded non-woven fabrics, thermal-bonded/non-woven fabrics, etc. It is formed from a material such as a composite nonwoven fabric laminated with spunbond, an open film such as an open polyethylene film, a foamed film such as polyethylene foam or urethane foam, or a composite sheet in which these are laminated. In addition, the top sheet 20 may be embossed or perforated on the surface in order to improve liquid permeability. As a method for applying these embossing and perforating processes, known methods can be implemented without limitation. In order to reduce irritation to the skin, the top sheet 20 may contain a lotion, an antioxidant, an anti-inflammatory ingredient, a pH adjuster, an antibacterial agent, a moisturizing agent, and the like.

The basis weight of the top sheet 20 is preferably 18 g/m ² or more and 40 g/m ^{2 or} less in terms of strength, processability, and liquid return amount. The shape of the top sheet 20 is not particularly limited as long as it covers the absorbent body 30 and is required to guide bodily fluids to the absorbent body 30 without leakage.

<Back seat>
The back sheet 21 may be formed using a liquid-impermeable base material that does not allow the body fluid retained by the absorbent body 30 to wet clothes, and may be formed by laminating a resin film or a resin film and a non-woven fabric. It is formed from a material such as a laminated composite sheet. The nonwoven fabric used for the composite sheet is not particularly limited in manufacturing method, and examples thereof include spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunbond/meltblown composite nonwoven fabrics, spunbond/meltblown/spunbond laminated composite nonwoven fabrics, and composite materials thereof. mentioned. Examples of resin films include polyester, polyvinyl alcohol, polyethylene, polypropylene, composite films of polyethylene and polypropylene, and the like.

From the viewpoint of strength and workability, the basis weight of the backsheet 21 is preferably 15 g/m ² or more and 40 g/m ² or less. In addition, it is preferable that the back sheet 21 has air permeability in order to prevent stuffiness during wearing. In order to make the back sheet 21 air-permeable, for example, a filler may be added to the base resin film, or the back sheet 21 may be embossed. Calcium carbonate can be used as a filler, and a known method can be used without limitation as a method for blending the filler.

<Absorber>
As shown in FIG. 1, in the absorbent article 1 of the present invention, the absorbent body 30 has an abdominal portion 30a, a crotch portion (crotch portion) 30b, and a back portion 30c. In the lamination direction, as shown in FIG. 2, the absorbent core 30 of the present invention is composed of an upper absorbent core 301 positioned on the skin contact side and a lower absorbent core 302 positioned on the non-skin contact side. Become.

As shown in FIG. 1, the longitudinal dimension L0 of the absorbent body 30 is preferably 400 mm or more and 780 mm or less, more preferably 420 mm or more and 650 mm or less.

The longitudinal dimension L1 of the ventral portion 30a of the absorber 30 is preferably 100 mm or more and 260 mm or less, and more preferably 110 mm or more and 220 mm or less. In addition, the maximum width dimension W1 in the width direction of the absorber 30 in the ventral portion 30a is preferably 140 mm or more and 300 mm or less, and more preferably 150 mm or more and 260 mm or less.

The longitudinal dimension L2 of the crotch portion 30b of the absorbent body 30 is preferably 80 mm or more and 200 mm or less, and more preferably 100 mm or more and 170 mm or less. Further, the maximum width W2 in the width direction of the absorbent body 30 in the crotch portion 30b is preferably 140 mm or more and 160 mm or less.

The longitudinal dimension L3 of the dorsal portion 30c of the absorbent body 30 is preferably 200 mm or more and 320 mm or less, and more preferably 210 mm or more and 300 mm or less. In addition, the longest dimension W3 in the width direction of the absorbent body 30 in the dorsal portion 30c is preferably 200 mm or more and 330 mm or less, and more preferably 220 mm or more and 320 mm or less.

The various dimensions L0 to L3 in the longitudinal direction of the absorbent body 30 described above apply to the upper absorbent body 301 and the lower absorbent body 302, respectively. That is, the upper layer absorbent body 301 and the lower layer absorbent body 302 may have the same length in the Y direction. On the other hand, the various dimensions W1 to W3 in the width direction of the absorbent body 30 may apply to only one of the upper absorbent body 301 and the lower absorbent body 302. be. In this case, the lower absorbent body 302 has, for example, a constant dimension in the width direction (same at each position in the Y direction), which may be the same as the dimension W2 of the upper absorbent body 301, for example.

The thickness of the absorbent body 30 is preferably 4 mm or more and 12 mm or less, and more preferably 5 mm or more and 10 mm or less.

The upper layer absorbent body 301 and the lower layer absorbent body 302 each contain absorbent fibers as a base material and a super absorbent polymer (SAP). The total basis weight of each of the upper absorbent core 301 and the lower absorbent core 302 is preferably 200 g/m ² or more and 500 g/m ² or less, more preferably 250 g/m ² or more and 400 g/m ² or less. .

Absorbent fibers are not particularly limited as long as they are generally used for absorbent articles such as sanitary napkins, paper diapers, and incontinence pads. nonwoven fabrics and the like. Among these, fluff pulp is preferably used from the viewpoint of absorbability. Examples of fluff pulp include wood pulp (for example, bleached softwood kraft pulp (N-BKP) such as southern pine and Douglas fir), synthetic fiber, resin fiber, non-wood pulp, etc., which are defibrated into cotton. can. When fluff pulp is used as the absorbent fiber as the base material in the absorbent body 30, the basis weight of the absorbent fiber is 100 g/m ² or more and 350 g/m ² or less in the entire upper layer absorbent body 301. It is preferably 150 ^g /m ² or ^more and 300 g/m ² or less ^. It is more preferably m ² or less. As a result, more bodily fluids can be absorbed without impairing the feel of the skin.

The lower absorbent body 302 is preferably formed from a raw material containing 30% or more and 70% or less of hardwood (eucalyptus) pulp, and more preferably formed of a raw material containing 35% or more and 60% or less of hardwood pulp. More preferably, it is formed from a raw material containing 40% or more and 50% or less of hardwood pulp. As a result, it is possible to reduce the thickness of the absorber with hardwood pulp, which has thin and short fibers. An absorbent body 30 is obtained.

The superabsorbent polymer is not particularly limited as long as it can absorb body fluids and prevent backflow. Sodium polyacrylate, polyaspartate, (starch-acrylic acid) graft copolymer, Those formed from materials such as (acrylic acid-vinyl alcohol) copolymers, (isobutylene-maleic anhydride) copolymers and saponified products thereof can be used. Among these, the sodium polyacrylate type is preferable from the viewpoint of the absorption amount per weight.

The basis weight of the SAP in the entire upper absorbent body 301 is preferably 50 g/m ² or more and 300 g/m ² or less, more preferably 100 g/m ² or more and 250 g/m ² or less. 302 as a whole is preferably 50 g/m ² or more and 300 g/m ² or less, more preferably 100 g/m ² or more and 250 g/m ² or less. Within the above numerical range, gel blocking in the absorbent body 30 can be prevented, and a large amount of body fluid can be absorbed in the absorbent body 30 .

In the upper absorbent body 301, the ratio of the weight of the superabsorbent polymer to the weight of the fluff pulp is preferably 20% or more and 100% or less, more preferably 30% or more and 80% or less. In the lower absorbent body 302, the ratio of the weight of the superabsorbent polymer to the weight of the fluff pulp is preferably 20% or more and 100% or less, more preferably 30% or more and 80% or less.

In the absorbent body 30, the form of the absorbent fibers and SAP is preferably formed by mixing SAP particles in absorbent fibers, or a SAP sheet in which SAP particles are fixed between absorbent fibers. For the purpose of preventing leakage of SAP particles and stabilizing the shape of the absorbent body 30, the absorbent body 30 may be wrapped in a carrier sheet. The base material of the carrier sheet may be any material as long as it is hydrophilic, and examples thereof include hydrophilic nonwoven fabrics such as tissues, absorbent paper, and air-laid nonwoven fabrics. When a plurality of carrier sheets are provided, the substrates of the carrier sheets may be the same or different.

(slit)
As shown in FIGS. 1 and 2, the absorbent article 1 of the present invention is provided with a pair of left and right linear slits 31 extending in the longitudinal direction of the absorbent body 30 at approximately the central portion in the width direction of the absorbent body 30. there is As a result, it is possible to secure a path for body fluids to diffuse within the absorbent body 30, and the absorbent article 1 having an excellent absorption rate can be obtained. The pair of slits 31 are formed symmetrically with respect to a straight line in the Y direction passing through the center of the absorbent body 30 in the width direction.

The slits 31 do not contain fluff pulp or superabsorbent polymer, and penetrate the upper absorbent core 301 and the lower absorbent core 302 in the thickness direction of the absorbent core 30 . Therefore, the form of the slits 31 is the same in each of the upper layer absorbent body 301 and the lower layer absorbent body 302 .

The slit 31 extends from the ventral portion 30a of the absorbent body 30 to the dorsal portion 30c via the crotch portion 30b. The slit 31 preferably has a longitudinal dimension L10 of 140 mm or more and 510 mm or less, more preferably 180 mm or more and 460 mm or less. In the slit 31, the ratio of the dimension L10 to the dimension L0 (=100×L10/L0) is preferably 35% or more and 65% or less, more preferably 40% or more and 60% or less. As a result, it is possible to obtain the effect of maintaining the diffusibility even under body pressure.

The gap W10 between the pair of slits 31 is preferably 15 mm or more and 70 mm or less, more preferably 20 mm or more and 60 mm or less. The interval W10 between the pair of slits 31 is preferably 10% or more and 50% or less of the dimension W2, and more preferably 14% or more and 40% or less of the dimension W2. The interval W10 corresponds to the minimum distance between the pair of slits 31 in the width direction, as shown in FIG.

In the pair of slits 31, in the crotch portion 30b of the absorbent body 30, the total slit width (=2 × W11) is preferably 7% or more and 25% or less of the width direction dimension W2 of the crotch portion 30b, 10% It is more preferable to be 22% or less. As a result, the effect of improving deformability and fitness is obtained.

The pair of slits 31 are preferably within 65% of the widthwise dimension (=W2/2) of the absorbent body 30 from the widthwise center of the absorbent body 30 at the crotch portion 30b of the absorbent body 30. % is more preferable. That is, it is preferable that the pair of slits 31 have a formed width (=W10+2×W11) within a range of 65% of the widthwise dimension W2 of the crotch portion 30b. As a result, the effect of improving deformability and fitness is obtained.

The gap W10 between the pair of slits 31 is preferably 15% or more, more preferably 20% or more, and even more preferably 25% or more of the widthwise dimension W2 of the crotch portion 30b. As a result, the effect of improving the adhesion to the crotch can be obtained.

(Perforated film)
The perforated film 40 is a resin film such as polyethylene. The perforated film 40 has a function of allowing bodily fluids to flow from the top sheet 20 side to the absorbent body 30 while suppressing backflow from the absorbent body 30 to the top sheet 20 side.

The perforated film 40 preferably has a basis weight of 20 g/m ² or more and 50 g/m ² or less, and more preferably 23 g/m ² or more and 40 g/m ² or less. As a result, it is possible to obtain the effect that the tactile sensation is not hard and the wearing comfort is good.

The perforated film 40 preferably has a thickness under no load of 0.6 mm or more and 1.0 mm or less, preferably 0.7 mm or more and 0.9 mm or less, and more preferably 0.7 mm or more and 0.8 mm or less. It is even more preferable to have As a result, it is possible to obtain the effect that reversion can be suppressed without causing discomfort in wearing comfort.

In the perforated film 40, the diameter d1 (see FIG. 2) of the perforated portions 40a is preferably 0.45 mm or more and 0.98 mm or less, preferably 0.5 mm or more and 0.9 mm or less, and 0.6 mm. It is more preferable that the distance is not less than 0.9 mm and not more than 0.9 mm. As a result, it is possible to obtain an effect that the balance between the suppression of backflow and the maintenance of absorbency becomes appropriate.

The diameter of the aperture 40a may be constant in the thickness direction, but the diameter varies in the thickness direction as shown in FIG. may Specifically, in FIG. 3, the aperture 40a may change in a manner that the diameter gradually decreases from the skin side toward the non-skin side. At this time, the difference between the opening diameter d11 on the skin side and the opening diameter d12 on the non-skin side may be 0.04 to 0.10 mm. As a result, the liquid absorbed from the skin side can be prevented from returning to the skin side (that is, backflow).

In the perforated film 40, the distance d2 between the perforated portions 40a (see FIG. 2) is preferably 0.3 mm or more and 0.9 mm or less, preferably 0.4 mm or more and 0.8 mm or less, and 0.4 mm or more and 0.8 mm or less. More preferably, it is 4 mm or more and 0.7 mm or less. As a result, it is possible to obtain an effect that the balance between the suppression of backflow and the maintenance of absorbency becomes appropriate.

<Effects of absorbent articles>
In the absorbent article 1 for nursing care in which the total length of the absorbent body 30 is 400 mm or more, by providing the slit 31 having a length of 35% to 55% with respect to the total length of the absorbent body 30, the absorption speed is increased by 150 ml × 3 times method. Fast absorbency is obtained in 25 seconds or less. Further, by forming the slits 31 long in the Y direction, diffusion from the cross section of the absorber 30 can be promoted and the absorption speed can be increased. On the other hand, forming the slits 31 long in the Y direction increases the amount of reversion, but by providing the perforated film 40 on the non-skin-contacting side of the top sheet 20, the reversion from the absorbent body 30 to the surface is effectively made. can be suppressed. As a result, an absorbent article with quick absorption and high dry feeling can be obtained.

The slit 31 is arranged to pass through the entire area of the crotch portion 30b in the Y direction. Since the total width (=2×W11) is 7% or more and 25% or less of the widthwise dimension W2 of the crotch portion 30b, the deformability of the crotch portion 30b from the ventral portion 30a of the absorbent body 30 is increased, The absorbent article 1 can easily be brought into close contact with the caregiver through the crotch when worn by the caregiver (especially effective for caregivers whose legs are difficult to move due to contracture, etc.), and the close contact state can be easily maintained even when the posture is changed. . In addition, since the slit 31 also extends into the dorsal portion 30c of the absorbent body 30, it is possible to prevent leakage by stably diffusing body fluid even under body pressure in the supine position.

Hereinafter, the present invention will be described in detail with reference to examples. It should be noted that the present invention is by no means limited to the examples shown below. In addition, below, the dimension W2 of the width direction of the crotch part 30b is also called "crotch width."

[Example 1]
[Preparation of absorbent article]
Fluff pulp obtained by pulverizing and fibrillating a pulp sheet and a superabsorbent polymer are laminated together to form an upper absorbent mat having a lengthwise dimension of 546 mm, a widthwise dimension of 180.5 mm at the ventral side, and a crotch portion. It was cut to 140 mm and 260 mm at the rear, and an upper absorbent body was produced with a fluff pulp weight of 22.5 g and a superabsorbent polymer weight of 11 g. The fluff pulp was compounded with 100% softwood pulp.

Two linear upper layer slits extending in the longitudinal direction of the upper layer absorbent are provided in the crotch portion of the upper layer absorbent, and the two upper layer slits are provided with an interval of 53 mm in the width direction of the upper layer absorbent, In addition, the width of each of the pair of upper layer slits symmetrical with respect to the center line in the width direction of the upper layer absorbent was set to 15 mm. The longitudinal dimension of the pair of upper layer inner slits located inside the width direction center line of the upper layer absorbent body is 300 mm, which is 55% of the total length of the upper layer absorbent body 546 mm, and the pair of upper layer inner slits exist. The width of the area where the slits are formed is (slit width 15 mm+interval 53 mm+slit width 15 mm=83 mm), which is 59% of the crotch width 140 mm. The total width of a pair of slits is (slit width 15 mm×2=30 mm), which is 21% of the crotch width of 140 mm.

A lower-layer absorbent mat obtained by pulverizing and defibrating a pulp sheet and laminating a superabsorbent polymer together is cut into a rectangular shape with a longitudinal dimension of 546 mm and a width dimension of 140 mm. Then, a lower absorbent body having a fluff pulp weight of 17.5 g and a superabsorbent polymer weight of 10 g was produced. The fluff pulp was blended with 50% softwood pulp and 50% eucalyptus pulp. A pair of slits were provided in the width direction at the same size and position as the upper absorbent body.

Between the top sheet and the back sheet, an absorbent body in which an upper layer absorbent body and a lower layer absorbent body are laminated is arranged, and the longitudinal dimension is 630 mm, the width dimension is 280 mm in the ventral part, 240 mm in the crotch part, and 320 mm in the dorsal part. , and pasted to a back sheet at the back side of the absorbent body to produce an absorbent article of a pad type disposable diaper. A perforated polyethylene film (basis weight: 27 g/m ² ) was placed over the entire length of the absorbent body on the non-skin contact side of the top sheet. An air-through nonwoven fabric (basis weight: 18 g/m ² ) was used for the top sheet, and a breathable polyethylene film (basis weight: 18 g/m ² ) was used for the back sheet.

The configuration of the absorbent article of the pad-type disposable diaper is shown in Tables 1 to 3, including those described above. Those with no configuration are indicated by "-".

[Evaluation of wearing comfort, evaluation of pad misalignment]
With the cooperation of eight panelists, the pad-type disposable diapers produced in Example 1 were worn, and a sensory evaluation was performed on the comfort of the incontinence absorbing pad and the slippage after wearing it overnight. Responses were obtained from the panelists who wore the pads regarding comfort, and from the person in charge of nursing care regarding the displacement of the pads after wearing. The wearing comfort was determined by sensory perception after wearing, and the displacement of the pad was determined by wearing it for 8 hours before going to bed, and evaluating whether or not there was any displacement of the pad due to movements such as rolling over after sleeping. In Table 4, regarding the evaluation of whether or not the pad is misaligned, "O" is given when 6 or more people evaluate "no misalignment" and 3 or more people evaluate "no misalignment". When 5 people or less were evaluated as "△", when 1 or 2 people evaluated "no deviation" or when no one evaluated "no deviation", it was evaluated as "x".

[Absorption rate]
A pad-type paper diaper was stretched and fixed on a flat surface, and a cylindrical jig with an inner diameter of 30 mm was installed at the center of the width direction and length direction of the skin-contacting side of the pad-type paper diaper, and 150 ml per use. of 0.9% physiological saline was injected, and the time until the surface of the paper diaper absorbed the liquid surface was measured. Three minutes after absorption, the next 150 ml was injected, and the time until absorption was similarly measured. This operation was repeated, and the total time required for absorption of 150 ml×3 times was taken as the absorption rate (seconds).

[Reverse amount]
The pad-type paper diaper was stretched flat and fixed in an unfolded state, and 1000 ml of 0.9% physiological saline was injected into the center of the width direction and length direction of the skin-contacting side of the pad-type paper diaper and allowed to stand for 10 minutes. . A filter paper was placed at the center of the width direction and the length direction of the pad-type paper diaper on the side of the skin contacting side, and a weight having a load of 35 g/m ² was further placed thereon and allowed to stand for 1 minute. After standing for 1 minute, the weight was removed, and the weight of the 0.9% physiological saline absorbed by the filter paper was determined from the weight difference before and after the absorption, and was defined as the amount of reversion (g).

[Comparative Examples 1 to 4]
Absorbent articles of Comparative Examples 1 to 4 were produced in the same manner as in Example 1, and the structure of the absorbent core of each absorbent article in Comparative Examples 1 to 4 is shown in Tables 1 to 3. Sensory evaluation of pad misalignment in Comparative Examples 1 and 2 was performed in the same manner as in Example 1, and the obtained evaluations are shown in Table 4. Items with no structure or items not evaluated are indicated by "-".

Comparative Example 1 differs from Example 1 in the configuration of the slits, specifically, the slit length is short. Various dimensions of the slit are as shown in Tables 1 to 3. In Comparative Example 1, the slit length was shorter than that in Example 1. Therefore, as shown in Table 4, the absorption speed was relatively low, and the comfort and wearing feeling of the absorbent article, as well as the slippage of the absorbent article after wearing it overnight, were relatively low. evaluation is not good.

Comparative Example 2 is different from Example 1 in that the perforated film 40 is not provided, and a non-perforated film (air-through nonwoven fabric) is used instead of the perforated film 40 . In Comparative Example 2, although the absorption speed and the like are equivalent to those of Example 1, the amount of backflow is greater.

Comparative Example 3 differs from Example 1 in that the crotch width is wider. In Comparative Example 3, although the absorption speed and the amount of reversion are equivalent to those of Example 1, the evaluation of wearing comfort, wearing feeling, and displacement of the absorbent article after wearing overnight is not good.

Comparative Example 4 differs from Example 1 in that only the softwood pulp, out of hardwood pulp and softwood pulp, was used as the raw material for forming the lower absorbent body 302 . In Comparative Example 4, the absorption speed and the amount of reversion are equivalent to those of Example 1, but the evaluation of wearing comfort and wearability is not good.

[Summary of the results of Example 1]
As shown in Example 1, when the width of the absorber and the length and arrangement of the pair of slits were specified in the specification of the present application, the evaluation of comfort and deviation of the urine absorption pad was "Good". For this reason, the absorber can be deformed in accordance with the posture and external force in the wearing operation and the wearer's daily movement, and the presence of relatively long slits allows urine to be quickly diffused and absorbed. By arranging the layer on the non-skin-contacting side of the top sheet, it was possible to effectively suppress reversion, and it was possible to provide an absorbent article with good wearability and dryness.

On the other hand, as shown in Comparative Examples 1 to 4, when the slit length was shorter than specified in the present application or when the crotch width of the absorber was wider, the evaluation of the comfort and deviation of the urine absorption pad was "x". rice field. For this reason, when the slit is short or when the crotch width of the absorbent body is wide, the deformability and adhesion at the time of wearing are insufficient, resulting in an absorbent article that does not provide a good fitting feeling. In addition, when the slit length was short, the absorption speed decreased, and when the air-through nonwoven fabric was used instead of the perforated film, the amount of backflow increased, and the absorption performance was lower than that of Example 1.

1 Absorbent Article 20 Top Sheet 30 Absorber 301 Upper Layer Absorber 302 Lower Layer Absorber 31 Slit 40 Perforated Film 40a Perforated Part

Claims (3)

An absorbent article comprising a liquid-permeable topsheet, a liquid-impermeable backsheet, and an absorbent body disposed between the topsheet and the backsheet,
The total length of the absorbent body is 400 mm or more, and the absorbent body is provided in two upper and lower layers in a layered manner,
In the two-layer absorbent body, slits each having a length of 35% or more and 65% or less of the total length of the absorbent body penetrate in a width direction in pairs,
The absorber includes a crotch portion having a relatively narrow width arranged in the crotch portion of the wearer, an abdominal portion having a relatively wide width arranged on the abdominal side and the back side of the wearer, and a dorsal portion. and
the slit extends from the ventral portion through the crotch portion to the dorsal portion;
crotch width of the absorber is 140 mm or more and 160 mm or less;
the width of the abdominal portion of the absorber is 140 mm or more and 300 mm or less;
The width of the dorsal portion of the absorbent body is 200 mm or more and 330 mm or less,
In the crotch width of the absorber, the total width of the pair of slits is 7% or more and 25% or less of the crotch width of the absorber,
The pair of slits are contained within a range of 65% of the crotch width of the absorber from the center in the width direction of the absorber,
The pair of slits are provided at intervals of 15% or more of the crotch width of the absorber,
An apertured film is provided on the non-skin contact side of the top sheet,
The perforated film has a plurality of perforations,
The upper layer absorbent body and the lower layer absorbent body of the upper layer of the absorbent body each contain an absorbent fiber as a base material and a superabsorbent polymer,
The absorbent article, wherein the absorbent fibers of the lower absorbent body are formed from a raw material containing 30% or more and 70% or less of hardwood (eucalyptus) pulp. The perforated film is a resin film having a basis weight of 20 g/m ² or more and 50 g/m ^{2 or} less and a thickness under no load of 0.6 mm or more and 1.0 mm or less . 2. The absorbent article according to claim 1, wherein the diameter of is 0.45 mm or more and 0.98 mm or less. 3. The perforated film according to claim 1 or 2, wherein the distance between the perforations is 0.3 mm or more and 0.9 mm or less, and the area ratio of the perforations is 28% or more and 43% or less. The absorbent article described.

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