WO2023276287A1

WO2023276287A1 - Absorbent article

Info

Publication number: WO2023276287A1
Application number: PCT/JP2022/010060
Authority: WO
Inventors: 亜希子長野
Original assignee: 大王製紙株式会社
Priority date: 2021-06-28
Filing date: 2022-03-08
Publication date: 2023-01-05
Also published as: TW202300126A; JP2023004767A

Abstract

[Problem] To improve the rising angle of an inwardly rising gather. [Solution] The problem is solved by a rising gather 60 having a root section 65 positioned further outside in the width direction WD than a blocking position, and a main body section 66 extending inward in the width direction WD without being folded back from the root section 65, wherein: the main body section 66 has a front-end section 67 and a rear end-section 69 having fixing sections BP fixed to a top sheet 30, and a middle section 68 not fixed to the top sheet 30; a gather elastic member 63 is attached to tip section of the middle section 68; free sections FP not fixed to the top sheet 30 are provided to be continuous from the middle section 68 at an inner-end section in the width direction WD in the front-end section 67 and the rear-end section 69; portions excluding the free sections FP of the front-end section 67 and the rear-end section 69 serve as the fixing sections BP; the width x1 of the free section FP is 1/6 to 1/3 of the width x2 of the middle section 68; and the dimension y1 of the free section FP in the front-rear direction LD is 1-9.5 times the width of the free section FP.

Description

absorbent article

The present invention relates to an absorbent article that improves the followability of the sit-up gathers.

At present, most absorbent articles such as disposable diapers and sanitary napkins are equipped with riser gathers (also called three-dimensional gathers) that rise from both sides in the width direction of the top sheet surface. By providing the rising gathers, lateral movement of the excrement is blocked by the rising gathers, and so-called side leakage is prevented.

Many of the rising gathers consist of a base portion attached to the outside in the width direction of an imaginary line continuing in the front-rear direction through blocking positions on both sides in the width direction of the surface of the top sheet, and a body portion extending from the inner edge in the width direction of the base portion. , a fixed portion in which the front and rear ends of the main body portion are fixed to the surface of the top sheet in a lying down state, and an intermediate portion located between the front and rear fixed portions in the main body portion and not fixed to the surface of the top sheet. and These parts are formed of gather sheets such as non-woven fabric. Of these, at least the tip of the rising gather has a two-layer structure in which the gather sheet is folded back at the tip (pointing end), and an elongated gather elastic member extends in the front-rear direction between the layers of at least the tip of the intermediate part. attached in an extended state along the (See Patent Documents 1 and 2, for example).

The intermediate portion is contracted together with the gather elastic member due to the contractile force of the gather elastic member, and is expandable together with the gather elastic member. In the attached state, the contractile force of the gathered elastic member shortens the front-to-rear dimension of the tip of the intermediate portion, and the intermediate portion is not fixed to the top sheet. part), and lower as it approaches the fixed parts of the front and rear ends.

In addition, in some absorbent articles such as tape-type disposable diapers, the main body of the riser gather extends inward in the width direction without being folded back from the base, and the tip of the main body faces inward in the width direction.

However, such an inward-facing type of sit-up gather has a problem that there is a limit to the sit-up angle (and therefore the sit-up height) in the crotch area, and the middle part that rises from the surface of the top sheet is difficult to fall outward, preventing loose stools from leaking. Although it is excellent in preventive properties, it has the problem that it is difficult to move outward following the movement of the leg in the lateral recumbent position, etc., and the tip tends to come into contact with the skin.

JP 2019-130278 A Japanese Unexamined Patent Application Publication No. 2018-140068

Therefore, the main object of the present invention is to improve the rising angle of the inward rising gathers.

The absorbent article that solves the above problems is as follows.
<First Aspect>
an absorber;
A liquid-permeable top sheet arranged on the front side of the absorbent body;
and rising gathers provided on both sides in the width direction of the surface of the top sheet,
The rising gathers are formed by folding back from the root portion attached to the outside in the width direction of an imaginary line continuing in the front-rear direction through the blocking positions on both sides in the width direction of the surface of the top sheet and the inner edge in the width direction of the root portion. a main body extending inward in the width direction without being broken;
The main body portion has a front end and a rear end having a fixed portion fixed to the top sheet, and an intermediate portion located between the front end and the rear end and not fixed to the top sheet. death,
An elongated gathered elastic member extending in the front-rear direction is attached to at least the tip of the intermediate portion,
the intermediate portion is contracted together with the gathers elastic member due to the contraction force of the gathers elastic member, and is expandable together with the gathers elastic member;
A free portion that is not fixed to the top sheet is provided at an inner end portion in the width direction of at least one of the front end portion and the rear end portion so as to continue from the intermediate portion. A fixed portion is provided at the rear end portion other than the free portion,
The width of the free portion is 1/6 to 1/3 of the width of the intermediate portion, and the dimension of the free portion in the front-rear direction is 1 to 9.5 times the width of the free portion.
An absorbent article characterized by:

(Effect)
In the conventional inward rising gathers, the front and rear fixing portions of the main body are provided over substantially the entire width of the main body. In this case, in the mounted state, the front and rear fixing portions suppress the rising of the intermediate portion over the entire width direction, so that the rising angle of the intermediate portion is reliably limited, and the tip of the intermediate portion is also suppressed from falling outward. In addition, the intermediate portion is less likely to move outward following the movement of the leg, and the tip of the intermediate portion tends to come into tight contact with the skin.
On the other hand, in the present absorbent article, a free portion (portion not fixed to the top sheet) having a certain width is provided at the inner end portion in the width direction of at least one of the front end portion and the rear end portion of the main body portion. is provided so as to continue from the middle part. For this reason, in the attached state, the front and rear fixed parts suppress the rising of the intermediate part, but the degree of suppression is the rising of the free part does not rise), the rising angle of the intermediate portion is surely larger than that in the case where there is no free portion. In addition, the presence of the free portion makes it easier for the tip of the intermediate portion to fall outward, and the intermediate portion to follow the movement of the leg and move outward. Furthermore, as a result, the tip of the intermediate portion is less likely to come into tight contact with the skin.

<Second Aspect>
The width of the free portion is 3.5 mm or more,
The intermediate portion has the gathers elastic member in a distal region with a width equal to the width of the free portion, and does not have the gathers elastic member in a region other than the distal region.
The absorbent article of the first aspect.

(Effect)
Although the width of the free portion can be determined as appropriate, it is preferably 3.5 mm or more. In addition, since the intermediate portion has the gathering elastic member only in the tip side region having a width equal to the width of the free portion, the portion having the gathering elastic member is less likely to come into tight contact with the skin, which is preferable.
The gathered elastic member may extend to the free portion, in which case it may be fixed, or it may be unfixed and not exerting a contractive force.

<Third Aspect>
An elongated inside elastic member extending in the front-rear direction is provided on the back side of the top sheet in the base portion side region equal to the width of the fixing portion in the region overlapping the back side of the intermediate portion in the unfolded state,
The base-side region is contracted together with the inside elastic member due to the contractile force of the inside elastic member, and is expandable together with the inside elastic member.
The absorbent article of the first or second aspect.

(Effect)
By providing the inside elastic member at the position of this aspect, the portion having the inside elastic member is lifted, and the portion that becomes the base of the rise gather is inclined so that the rise angle of the intermediate portion is increased, which is preferable.

<Fourth Aspect>
The absorbent body has a constricted portion narrower in width than both front and rear sides thereof in the middle in the front-rear direction,
The inside elastic member is arranged to pass through the constricted portion,
The absorbent article of the third aspect.

(Effect)
Since the constricted portion is a portion that does not have an absorbent body, it has lower rigidity than the portion that has an absorbent body and is easily deformed. Therefore, if the inside elastic member is provided so as to pass through this position, the base portion of the rising gathers is more likely to be inclined, which is preferable.

<Fifth Aspect>
both the front end and the rear end have the free portion;
The width of the free portion of the front end is wider than the width of the free portion of the rear end,
The absorbent article according to any one of the first to fourth aspects.

(Effect)
Since the range of motion of the leg is larger on the front side than on the rear side, it is one preferable mode to make the width of the free portion of the front end portion of the body portion wider than the width of the free portion of the rear end portion as in this mode. .

<Sixth Aspect>
Disposable diapers for low birth weight babies,
The absorbent article according to any one of the first to fifth aspects.

(Effect)
A weak but flexible fit is preferred over a tight fit in disposable diapers for low birth weight infants. Therefore, the riser gathers having the above-described free portion are suitable for disposable diapers for low birth weight infants.

According to the present invention, advantages such as being able to suppress exudation of excreted fluid at the base of the riser gathers are brought about.

Fig. 2 is a plan view showing the inner surface of the connectable disposable diaper in an unfolded state; Fig. 2 is a plan view showing the outer surface of the connectable disposable diaper in an unfolded state; 6 is a cross-sectional view taken along line 6-6 of FIG. 1; FIG. FIG. 7 is a cross-sectional view taken along line 7-7 of FIG. 1; FIG. 2 is a cross-sectional view taken along line 8-8 of FIG. 1; 5 is a cross-sectional view taken along line 5-5 of FIG. 1; FIG. FIG. 4 is a cross-sectional view showing an enlarged main part of the rising gathers; FIG. 4 is a cross-sectional view showing an enlarged main part of the rising gathers; It is a perspective view which shows the inner surface of the mounted state roughly. Fig. 2 is a plan view showing the inner surface of the connectable disposable diaper in an unfolded state; Fig. 2 is a plan view showing the inner surface of the connectable disposable diaper in an unfolded state;

1 to 6 show a connected disposable diaper (generally also referred to as a tape type disposable diaper) which is an example of an absorbent article, and the symbol X in the figures indicates the full width of the diaper excluding the connecting tape 13. , and symbol L indicates the total length of the diaper. Note that, unless otherwise indicated, the dotted pattern portions and the asterisks (*) in the cross-sectional views indicate hot-melt adhesives as joining means for joining the components positioned on the front and back sides. The hot-melt adhesive can be applied by slot coating, continuous-line or dotted-line bead coating, spiral-shaped, Z-shaped, wavy-shaped spray coating, or pattern coating (transfer of hot-melt adhesive by letterpress method). can be applied by any method. Alternatively or additionally, at the fixing portion of the elastic member, a hot melt adhesive can be applied to the outer peripheral surface of the elastic member to fix the elastic member to the adjacent member. Hot-melt adhesives include, for example, EVA-based, adhesive rubber-based (elastomer-based), olefin-based, and polyester-polyamide-based adhesives, and can be used without particular limitation. As a fixing or joining means for joining each constituent member, a material welding means such as heat sealing or ultrasonic sealing can be used. In portions where liquid permeability in the thickness direction is required, adjacent components in the thickness direction are fixed or joined in an intermittent pattern. For example, when such intermittent fixing or bonding is performed with a hot-melt adhesive, intermittent pattern coating such as spiral, Z-shaped, and wavy patterns can be preferably used, and the range of coating width by one nozzle or more can be preferably used. In the case of coating, intermittent pattern coating such as spiral, Z-shape, wave-like, etc. can be performed with or without spacing in the width direction.

This connected disposable diaper has a crotch portion M including the center in the front-rear direction LD, an abdominal portion F extending forward from the center in the front-rear direction LD, and a back portion B extending rearward from the center in the front-rear direction LD. have. In addition, this connected disposable diaper includes an absorbent body 56 built in a range including the crotch portion M, a liquid-permeable top sheet 30 covering the front side of the absorbent body 56, and a liquid-impermeable body covering the back side of the absorbent body 56. and an exterior nonwoven fabric 12 that covers the back side of the liquid-impermeable sheet 11 and constitutes the outer surface of the product. The crotch portion M means the range in the front-rear direction LD having the constricted portion 56n when the absorber 56 has the constricted portion 56n described later, and the front-rear direction LD when the absorber 56 does not have the constricted portion 56n. It means the part located in the center of the product and the dimension in the front-rear direction LD is 30 to 60% of the total product length.

The materials and characteristic parts of each part will be described in order below. In addition, as the nonwoven fabric in the following description, a known nonwoven fabric can be appropriately used depending on the site and purpose. Constituent fibers of non-woven fabrics include, for example, synthetic fibers such as olefin-based, polyester-based, and polyamide-based fibers such as polyethylene or polypropylene (including composite fibers such as core-sheath fibers in addition to single-component fibers), as well as recycled rayon and cupra. Fibers, natural fibers such as cotton, etc., can be selected without particular limitation, and these can also be mixed and used. In order to increase the softness of the nonwoven fabric, it is preferable to use crimped fibers as the constituent fibers. In addition, even if the constituent fibers of the nonwoven fabric are hydrophilic fibers (including fibers made hydrophilic by a hydrophilic agent), they are hydrophobic fibers or water-repellent fibers (including fibers made water-repellent by a water-repellent agent). ). In addition, nonwoven fabrics are generally classified into short fiber nonwoven fabrics, long fiber nonwoven fabrics, spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunlace nonwoven fabrics, thermal bonded (air-through) nonwoven fabrics, and needle punched nonwoven fabrics, depending on the fiber length, sheet forming method, fiber bonding method, and laminate structure. Nonwoven fabrics are classified into nonwoven fabrics, point-bonded nonwoven fabrics, laminated nonwoven fabrics (including SMS nonwoven fabrics in which a meltblown layer is sandwiched between spunbond layers, SMMS nonwoven fabrics, etc.), etc., and any of these nonwoven fabrics can be used.
(Absorber)
The absorbent body 56 is a part that absorbs and retains the excreted fluid, and can be formed by an assembly of fibers. The filament assembly may be a filament assembly obtained by laminating short fibers such as cotton pulp or synthetic fibers, or by opening tows (fiber bundles) of synthetic fibers such as cellulose acetate as necessary. can also be used. The fiber basis weight can be, for example, about 100 to 300 g/m ² when piling up cotton-like pulp or short fibers, and for example, about 30 to 120 g/m ² for filament aggregates. can be done. The fineness of synthetic fibers is, for example, 1 to 16 dtex, preferably 1 to 10 dtex, more preferably 1 to 5 dtex. In the case of a filament assembly, the filaments may be non-crimped fibers, but crimped fibers are preferred. The degree of crimping of the crimped fibers can be, for example, about 5 to 75, preferably 10 to 50, more preferably 15 to 50 per 2.54 cm. Further, uniformly crimped crimped fibers can be used.

The shape of the absorber 56 can be determined as appropriate. For example, the absorber 56 may be formed in a substantially hourglass shape having a constricted portion 56n whose width is narrower than the front and rear sides of the portion located in the crotch portion M as shown in the illustrated example, or may be formed in an appropriate shape such as a rectangular shape. be able to. The absorber 56 is normally preferably provided from the front side to the back side of the crotch portion, but is not limited to this.

(superabsorbent polymer particles)
Absorbent body 56 may contain superabsorbent polymer particles in part or in its entirety. Superabsorbent polymer particles include "powder" in addition to "particles". As the superabsorbent polymer particles, those used in this type of absorbent article can be used as they are. Although the particle size of the superabsorbent polymer particles is not particularly limited, for example, sieving using a 500 μm standard sieve (JIS Z8801-1: 2006) (shaking for 5 minutes), and particles falling under the sieve in this sieving When sieving (shaking for 5 minutes) using a 180 μm standard sieve (JIS Z8801-1: 2006), the percentage of particles remaining on the 500 μm standard sieve is 30% by weight or less, and the 180 μm standard sieve It is desirable that the proportion of particles remaining on the top is 60% by weight or more.

The material for the superabsorbent polymer particles can be used without any particular limitation, but those with a water absorption of 40 g/g or more are suitable. Superabsorbent polymer particles include starch-based, cellulose-based, and synthetic polymer-based particles. and acrylic acid (salt) polymers can be used. As for the shape of the superabsorbent polymer particles, the powder particles that are commonly used are suitable, but other shapes can also be used.

As the superabsorbent polymer particles, those with a water absorption rate of 70 seconds or less, particularly 40 seconds or less are preferably used. If the water absorption rate is too slow, the liquid supplied into the absorbent body 56 tends to return to the outside of the absorbent body 56, which is called reversion.

Also, as the superabsorbent polymer particles, those having a gel strength of 1000 Pa or more are preferably used. As a result, even when the absorbent body 56 is bulky, it is possible to effectively suppress the feeling of stickiness after liquid absorption.

The basis weight of the superabsorbent polymer particles can be appropriately determined according to the absorption amount required for the use of the absorbent body 56 . Therefore, although it cannot be generalized, it can be usually 50 to 350 g/m ² .

(packaging sheet)
In order to prevent the superabsorbent polymer particles from slipping out or to improve the shape retention of the absorbent body 56, the absorbent body 56 can be incorporated as an absorbent element 50 wrapped with a wrapping sheet 58. FIG. As the wrapping sheet 58, tissue paper, especially crepe paper, nonwoven fabric, poly-laminated nonwoven fabric, a sheet with small holes, or the like can be used. However, it is desirable that the sheet is such that the superabsorbent polymer particles do not escape. When non-woven fabric is used instead of crepe paper, hydrophilic SMMS (spunbond/meltblown/meltblown/spunbond) nonwoven fabric is particularly suitable, and polypropylene, polyethylene/polypropylene, etc. can be used as the material. The fiber basis weight is preferably 5 to 40 g/m ² , particularly 10 to 30 g/m ² .

As shown in FIG. 3, the packaging sheet 58 may have a structure that wraps the entire absorbent body 56 with one sheet, or may wrap the entire absorbent body 56 with a plurality of sheets, such as two upper and lower sheets. The packaging sheet 58 can also be omitted.

(top sheet)
The top sheet 30 is liquid-permeable, and may be, for example, a perforated or non-perforated nonwoven fabric, or a perforated plastic sheet.

Although the top sheet 30 extends from the front end to the rear end of the product in the front-rear direction, it can be appropriately deformed as necessary. In addition, the illustrated top sheet 30 extends outside the boundary between the body portion 66 and the base portion 65 of the rising gathers 60 described later in the width direction WD, but is not limited to this. The illustrated top sheet 30 extends laterally beyond the side edges of the absorbent body 56, but if necessary, the side edges of the top sheet 30 may be positioned inside the side edges of the absorbent body 56, for example. Appropriate modifications are possible.

(intermediate sheet)
Although not shown, an intermediate sheet (also called a "second sheet") may be provided adjacent to the back side of the top sheet 30 in order to prevent liquid that has permeated the top sheet 30 from returning.

As the intermediate sheet, various nonwoven fabrics can be suitably used, and particularly bulky air-through nonwoven fabrics can be suitably used. Composite fibers having a core-sheath structure are preferably used for the air-through nonwoven fabric. In this case, the resin used for the core may be polypropylene (PP), but polyester (PET) having high rigidity is preferable. The basis weight is preferably 17-80 g/m ² , more preferably 25-60 g/m ² . The thickness of the raw fibers of the nonwoven fabric is preferably 2.0 to 10 dtex. In order to make the non-woven fabric bulky, it is also preferable to use eccentric fibers, hollow fibers, or eccentric and hollow fibers whose core is not in the center as mixed fibers of all or part of the raw material fibers.

The intermediate sheet may be shorter than the width of the absorbent body 56 and arranged in the center, or may be arranged so as to cover the entire width of the absorbent body 56 . Further, the intermediate sheet may be provided over the entire length of the diaper, or may be provided only in the intermediate portion including the excretion position.

(liquid-impermeable sheet)
The liquid-impermeable sheet 11 is not particularly limited, but preferably has moisture permeability. As the liquid-impermeable sheet 11, for example, an inorganic filler is kneaded in an olefin resin such as polyethylene or polypropylene, the sheet is molded, and then the sheet is stretched in a uniaxial or biaxial direction. A sheet can be preferably used. Moreover, as the liquid-impermeable sheet 11, a non-woven fabric as a base material with improved waterproofness can also be used.

It is preferable that the liquid-impermeable sheet 11 has an extension portion extending outward in the width direction WD from the top sheet 30 . It is desirable that the liquid-impermeable sheet 11 extends in the same or wider range than the absorber 56 in the front-rear direction LD and the width direction WD.

(exterior non-woven fabric)
The exterior nonwoven fabric 12 covers the entire back side of the liquid-impermeable sheet 11 to give the outer surface of the product a cloth-like appearance. The non-woven fabric can be used singly or in multiple layers. In the latter case, it is preferable to bond the nonwoven fabrics together with a hot-melt adhesive or the like. When a nonwoven fabric is used, it is preferable that the nonwoven fabric has a fineness of 1.0 to 6.0 dtex, a basis weight of 15 to 45 g/m ² and a thickness of 0.5 to 3.0 mm.

A sheet other than a nonwoven fabric can be used instead of the exterior nonwoven fabric 12, and the exterior nonwoven fabric 12 can be omitted.

(end flap part, side flap part)
The connected disposable diaper of the illustrated example has a pair of end flap portions EF without the absorbent body 56 extending to the front side and the rear side of the absorbent body 56 respectively, and a pair of end flap portions EF extending laterally from both side edges of the absorbent body 56 . It has a pair of side flap portions SF which do not have the absorber 56 and which extend from each other. The side flap portions SF may be made of a material (exterior nonwoven fabric 12 or the like) that continues from the portion having the absorber 56 as shown in the drawing, or may be formed by attaching another material.

(Wing part)
In this connected disposable diaper, the back side portion B has a wing portion WP that extends outward in the width direction WD from the crotch portion M. As shown in FIG. Similarly, the ventral portion F also has a wing portion WP extending outward in the width direction WD from the crotch portion M. These wing portions WP can also be formed of a member different from the other portions. However, in the structure having the side flap portions SF as in the illustrated example, by cutting the middle of the side portion of the side flap portion SF in the front-rear direction LD, the side edge of the crotch portion M to the lower edge 71 of the wing portion WP can be removed. Forming the constricted side edge 70 of the wing and forming the wing portion WP as a result is preferred for ease of manufacture.

(connecting tape)
As shown in FIGS. 1, 2 and 6, the wing portions WP of the dorsal portion B are provided with connecting tapes 13 that are detachably connected to the outer surface of the ventral portion F. As shown in FIGS. When wearing the diaper 10, the connecting tape 13 is wrapped around the outer surface of the abdominal portion F from both sides of the waist, and the connecting portions 13A of the connecting tape 13 are connected to the outer surface of the abdominal portion F at appropriate locations.

As shown in FIG. 6, the connecting tape 13 includes a base end portion 13C fixed to the wing portion WP, a main body portion 13B extending from the base end portion 13C, a sheet base material, and a main body of the sheet base material. and a connecting portion 13A for the ventral portion F provided in the middle portion in the width direction WD of the portion 13B. The base end portion 13C side of the connecting portion 13A in the main body portion 13B is a non-connecting portion that is not connected to the ventral portion F. As shown in FIG. The side edge of the base end portion 13C may coincide with the side edge of the wing portion WP, or may be slightly spaced inward in the width direction WD from the side edge of the wing portion WP as shown in the figure. good. The inner edge in the width direction of the connecting portion 13A may coincide with the side edge of the wing portion WP, but as shown in FIG. Preferably, they are spaced apart.

As the connecting portion 13A, in addition to providing a hook material (male material) of a mechanical fastener (surface fastener), an adhesive layer may be provided. The hook material has a large number of engaging projections on its connection surface, and the shapes of the engaging projections are (A) square-shaped, (B) J-shaped, (C) mushroom-shaped, and (D). Although there are a T shape, (E) a double J shape (a shape in which two J shapes are joined back to back), and the like, any shape may be used.

Nonwoven fabric, plastic film, poly-laminated nonwoven fabric, paper, and composite materials thereof can be used as the sheet base material forming the base end portion 13C to the main body portion 13B. A spunbond nonwoven fabric, an air-through nonwoven fabric, or a spunlaced nonwoven fabric having a basis weight of 60 to 100 g/m ² and a thickness of 1 mm or less is preferred.

The connecting tape 13 may be one in which at least a part of the non-connecting portion is stretchable in the width direction WD, or the whole is not stretchable.

(Target part)
A target portion 12T is provided at a connecting portion of the connecting tape 13 in the ventral portion F. As shown in FIG. The target portion 12T can be provided by attaching a sheet material to the outer surface of the ventral portion F to facilitate connection, as shown in the illustrated example.

The sheet material for forming the target portion 12T is not particularly limited. Non-woven fabrics can be used.

When the connecting portion 13A is made of a hook material, a large number of loop threads that engage the engaging projections of the hook material are sewn onto the surface of the base material made of plastic film or non-woven fabric as a sheet material for forming the target portion 12T. A laminated composite sheet material can be used.

Furthermore, when the connecting portion 13A is a hook material and the connecting portion of the connecting tape 13 in the ventral portion F is made of nonwoven fabric (for example, when the outer nonwoven fabric 12 is provided as in the illustrated example), the target portion 12T is formed. Therefore, without adding a sheet material, a suitable portion of the exterior nonwoven fabric 12 may be used as the target portion 12T, and the hook material may be entangled with the fibers of the exterior nonwoven fabric 12 to be connected.

On the other hand, when the connecting portion 13A is an adhesive layer, the surface of a sheet material made of a highly adhesive plastic film with a smooth surface is subjected to release treatment as a sheet material for forming the target portion 12T. can use things.

(Getting up gathers)
In order to block excrement moving laterally along the top sheet 30 and prevent so-called lateral leakage, the surface of the top sheet 30 is provided with riser gathers 60 on both sides in the width direction WD.

The rising gathers 60 are composed of a root portion 65 attached outside the width direction WD of an imaginary line 60B extending in the front-rear direction LD through blocking positions on both sides of the surface of the top sheet 30 in the width direction WD, and a body portion 66 extending inward in the width direction WD without being folded back from the inner edge of the body portion 66; The body portion 66 has a front end portion 67 and a rear end portion 69 having a fixing portion BP fixed to the top sheet 30 (in other words, the range of the body portion 66 in the front-rear direction LD having the fixing portion BP is the front end portion 67). and a rear end portion 69), and an intermediate portion 68 positioned between the front end portion 67 and the rear end portion 69 and not fixed to the top sheet 30. At least the tip portion of the intermediate portion 68 is attached with an elongated gather elastic member 63 extending in the front-rear direction LD.

The body portion 66 and the base portion 65 are folded in two at the tip of the body portion 66 (the end opposite to the side of the base portion 65) to form a two-layer structure of the inner layer 62n and the outer layer 62f. can be formed by In this case, a gather elastic member 63 can be provided between the inner layer 62n and the outer layer 62f. The inner layer 62n may extend to the base portion 65 as shown in FIG. 3, or may extend only to an intermediate position in the width direction WD of the main body portion 66 (not shown). In other words, the body portion 66 may have a single layer portion on the base portion 65 side. Also, the gather sheet 62 may have a layered structure of three or more layers, and in particular may have a liquid-impermeable film as an intermediate layer. When the gather sheet 62 has a multi-layer structure, the number of layers may be increased by attaching another nonwoven fabric without folding one sheet of nonwoven fabric or by folding one sheet of nonwoven fabric to increase the number of layers. .

The root portion 65 has a joining start end in the width direction WD on the side portion of the top sheet 30, and this joining start end continues in the front-rear direction LD through the blocking position. In addition, the root portion 65 of the illustrated example has an extending portion that extends outward in the width direction WD from the top sheet 30, and this extending portion corresponds to the inner surface of each side flap portion SF, that is, the illustrated example. In , the liquid-impermeable sheet 11 is joined to the side portion thereof and to the side portion of the exterior nonwoven fabric 12 positioned outside in the width direction WD thereof by a hot-melt adhesive or the like.

Although fixed portions BP fixed to the surface of the top sheet 30 are provided at both ends of the main body portion 66 in the front-rear direction LD, an intermediate portion 68 positioned between the front and rear fixed portions BP is fixed to the surface of the top sheet 30. This is the part that is not. The intermediate portion 68 is contracted together with the gathers elastic member 63 due to the contraction force of the gathers elastic member 63 and is expandable together with the gathers elastic member 63 . As a result, in the attached state, the contractile force of the gather elastic member 63 shortens the dimension of the tip of the intermediate portion 68 in the front-rear direction LD, and the intermediate portion 68 is not fixed to the top sheet 30. As shown in FIG. 9, the height of the intermediate portion 68 increases as it approaches the tip (the portion farthest from the base portion 65 side), and the height decreases as it approaches the fixing portion BP of the front end portion 67 and the rear end portion 69. get up.

The type of the gather sheet 62 is not particularly limited, but in general, a water-repellent nonwoven fabric is used from the viewpoint of touch and liquid barrier properties. In particular, a nonwoven fabric having a meltblown layer between spunbond layers (SMS nonwoven fabric, SMMS nonwoven fabric, SSMS nonwoven fabric, SSMMS nonwoven fabric) is preferable in that both good texture and liquid impermeability can be achieved. The non-woven fabric can be used singly or in multiple layers. In the latter case, it is preferable to bond the nonwoven fabrics together with a hot-melt adhesive or the like.

As the gather elastic member 63, an elastic member such as a thread-shaped, string-shaped, belt-shaped, and elongated rubber can be used. The gather elastic member 63 may be provided on each side only one as in the illustrated example, or may be provided on each side in plural. The elongation rate of the gather elastic member 63 in the unfolded state can be appropriately determined, but is preferably about 150 to 250%, more preferably 180 to 230%. When synthetic thread rubber such as spandex is used as the gathering elastic member 63, its thickness is preferably 300 to 700 dtex, more preferably 400 to 500 dtex.

Characteristically, a free portion FP that is not fixed to the top sheet 30 is provided so as to continue from the intermediate portion 68 at the inner end portions in the width direction WD of the front end portion 67 and the rear end portion 69 of the main body portion 66 . In addition, the portion of the body portion 66 other than the free portion FP serves as the fixed portion BP. The width x1 of the free portion FP is 1/6 to 1/3 of the width x2 of the intermediate portion 68, and the dimension of the free portion FP in the front-rear direction LD is 1 to 9.5 of the width x1 of the free portion FP. has doubled. Although the width x1 of the free portion FP is constant in the illustrated example, it may vary depending on the position in the front-rear direction LD, in which case it means the minimum value. Although the width x2 of the intermediate portion 68 is constant in the illustrated example, it may vary depending on the position in the front-rear direction LD, in which case it means the maximum value.

In such an inward rising gather 60, as shown in FIGS. 7 and 9, the front and rear fixed portions BP suppress the rising of the intermediate portion 68 in the attached state, but the extent of the suppression depends on the rising of the free portion FP. (Although it rises so as to follow the intermediate portion 68, it does not rise as much as the intermediate portion 68 because the width x1 of the free portion FP is short). sure to grow. In addition, due to the presence of the free portion FP, as shown in FIG. 8, the tip of the intermediate portion 68 tends to fall outward, and the intermediate portion 68 tends to move outward following the movement of the leg. Furthermore, as a result, the tip of the intermediate portion 68 is less likely to come into tight contact with the skin.

The dimensions of the free portion FP can be appropriately determined within the above range. The width x1 of the free portion FP is particularly preferably 2/11 to 1/4 of the width x2 of the intermediate portion 68. FIG. More specifically, the lower limit of the width x1 of the free portion FP is preferably 3.5 mm. Further, when both the front end portion 67 and the rear end portion 69 have the free portion FP, the width x1 of the free portion FP of the front end portion 67 and the width x1 of the free portion FP of the rear end portion 69 may be equal. Since the range of motion of the leg is larger on the front side than on the rear side, as shown in FIG. (For example, 1.2 to 1.5 times) is one preferred mode.

The dimension y1 of the free portion FP in the front-rear direction LD is more preferably 2 to 8.5 times the width x1 of the free portion FP. As in the example shown in FIG. 1, the free portion FP extends over the entire length of the front end portion 67 when provided at the front end portion 67 of the main body portion 66, and at the rear end portion when provided at the rear end portion 69 of the main body portion 66. 69 is preferably provided over its entire length. However, when the free portion FP is provided at the front end portion 67, as shown in FIG. 11, the free portion FP is provided only on the rear side of the front end portion 67, and the front side of the front end portion 67 is the fixed portion BP over the entire width direction WD. can also Similarly, when the free portion FP is provided at the rear end portion 69, as shown in FIG. Part BP can also be used. As can be seen from this, when the free portion FP is provided at both the front end portion 67 and the rear end portion 69 of the main body portion 66, the dimension of the free portion FP of the front end portion 67 in the front-rear direction LD and the free portion of the rear end portion 69 are The dimensions of the FP in the longitudinal direction LD may be equal to or different from each other. The free portion FP is preferably provided on both the front end portion 67 and the rear end portion 69 of the main body portion 66 as shown in the figure, but may be provided only on the front end portion 67 or only on the rear end portion 69 .

Unlike the illustrated example, the gather elastic member 63 may be provided at a portion other than the distal end portion of the intermediate portion 68. It is preferable not to have the gather elastic member 63 in areas other than the area because the portion having the gather elastic member 63 is less likely to come into tight contact with the skin.

Also, the gather elastic member 63 may extend to the free portion FP, or may not extend to the free portion FP. In the former case, the portion of the gathers elastic member 63 located in the free portion FP may be fixed to the free portion FP, and the contractile force of the gathers elastic member 63 may act on the free portion FP. The portion positioned in the free portion FP may not be fixed to the free portion FP, and the contractile force of the gather elastic member 63 may not act on the free portion FP.

(Inside plane gather)
As shown in the illustrated example, an elongated inside along the front-rear direction LD is located on the back side of the top sheet 30 in the base portion side region equal to the width x3 of the fixing portion BP in the region overlapping the back side of the intermediate portion 68 in the unfolded state. An elastic member 61 is provided, and the root side region is contracted together with the inside elastic member 61 by the contractile force of the inside elastic member 61, and is extensible together with the inside elastic member 61 (so-called planar gathers). ) and preferred. By providing such an inside elastic member 61, the portion having the inside elastic member 61 is lifted in the direction indicated by the white arrow in FIGS. can be tilted (this situation is not represented in FIGS. 7 and 8). The inside elastic member 61 can also be omitted.

The position of the inside elastic member 61 can be appropriately determined within the above range. As an example, the position of the inside elastic member 61 in the width direction WD is preferably within 10 mm, particularly within 7.5 mm in the width direction WD from the blocking position (the boundary between the base portion 65 and the intermediate portion 68). Further, when the position of the front end of the product in the front-rear direction LD is 0% and the position of the rear end of the product is 100%, the front end of the portion that expands and contracts by the inside elastic member 61 is located in the range of 20 to 30%. It is preferable that the rear end of the portion that expands and contracts by the member 61 is positioned within the range of 20 to 30%. When a constricted portion 56n having a narrower width than both front and rear sides thereof is formed in the middle of the absorber 56 in the front-rear direction LD (in particular, the range in the front-rear direction LD including the crotch portion M) as in the illustrated example, the inside The elastic member 61 is preferably arranged so as to pass through the constricted portion 56n. Since the constricted portion 56n is a portion that does not have the absorber 56, it has lower rigidity than the portion that has the absorber 56 and is easily deformed. Therefore, if the inside elastic member 61 is provided so as to pass through this position, the base portion of the rising gathers 60 is more likely to be inclined.

The inside elastic member 61 can be provided between the packaging sheet 58 and the liquid-impermeable sheet 11 and also between the liquid-impermeable sheet 11 and the exterior nonwoven fabric 12 . Only one inside elastic member 61 may be provided on each side as in the illustrated example, or a plurality of inside elastic members 61 may be provided on each side at intervals in the width direction.

As the inside elastic member 61, an elastic member such as a thread-like, string-like, band-like, and elongated rubber can be used. Only one inside elastic member 61 may be provided on each side as in the illustrated example, or a plurality of inside elastic members 61 may be provided on each side. The elongation rate of the inside elastic member 61 in the unfolded state can be appropriately determined, but is preferably about 160 to 240%, more preferably 180 to 220%. When synthetic thread rubber such as spandex is used as the inside elastic member 61, its thickness is preferably 400 to 700 dtex, more preferably 500 to 650 dtex.

The contractile force acting portion of the inside elastic member 61 (the portion where the inside elastic member 61 is shown in the drawing) may be the same as or shorter than the portion where the inside elastic member 61 exists. In other words, the inside elastic member 61 exists on the front side, the rear side, or both sides of the contractile force acting portion of the inside elastic member 61, but the inside elastic member 61 is not fixed to the sheets sandwiching the inside elastic member 61 except for the contractile force acting portion. Or, the inside elastic member 61 is finely cut at one place or multiple places, or both, so that the contractile force does not act (substantially, it is equivalent to not providing the elastic member). , the portion where the contractile force is applied may be shorter than the portion where the inside elastic member exists.

(Outside plane gather)
An outside elastic member 64 is provided outside the blocking position of each side flap portion SF in the width direction WD, and the portion around the leg of each side flap portion SF contracts together with the outside elastic member 64 due to the contractile force of the outside elastic member 64. In addition, it may be stretchable together with the outside elastic member 64 (it may be a so-called flat gather). The outside elastic member 64 can also be omitted.

The outside elastic member 64 is provided between the gather sheet 62 and the liquid-impermeable sheet 11 as shown in the figure, and also provided between the liquid-impermeable sheet 11 and the exterior nonwoven fabric 12 in the side flap portion SF. can also Only one outside elastic member 64 may be provided on each side as in the illustrated example, or a plurality of outside elastic members 64 may be provided on each side at intervals in the width direction.

As the outside elastic member 64, an elastic member such as thread-like, string-like, belt-like and elongated rubber can be used. Only one outside elastic member 64 may be provided on each side as in the illustrated example, or a plurality of outside elastic members 64 may be provided on each side. The elongation rate of the outside elastic member 64 in the unfolded state can be appropriately determined, but is preferably about 170 to 250%, more preferably about 190 to 230%. When synthetic thread rubber such as spandex is used as the outside elastic member 64, its thickness is preferably 400 to 700 dtex, more preferably 500 to 650 dtex.

The contractile force acting portion of the outside elastic member 64 (the portion where the outside elastic member 64 is illustrated in the drawing) may be the same as or shorter than the portion where the outside elastic member 64 exists. That is, the outside elastic member 64 exists on the front side, the rear side, or both sides of the contractile force acting portion of the outside elastic member 64, but is fixed to the sheets sandwiching the outside elastic member 64 except for the contractile force acting portion. or the outside elastic member 64 is finely cut at one or a number of locations, or both, the contractile force does not act (substantially, the elastic member is not provided). ), the contraction force acting portion may be shorter than the portion where the outside elastic member 64 exists.

<Description of terms in the specification>
When the following terms are used in the specification, they shall have the following meanings, unless stated otherwise in the specification.

"MD direction" and "CD direction" mean the flow direction (MD direction) and the transverse direction (CD direction) perpendicular to this in the manufacturing equipment, one of which is the front-back direction of the product, The other is the width direction of the product. The MD direction of a nonwoven fabric is the direction of fiber orientation of the nonwoven fabric. The fiber orientation is the direction along which the fibers of the nonwoven fabric are aligned. It can be determined by a simple measurement method for determining the orientation direction.

・"Front-back direction" means the direction (longitudinal direction) indicated by symbol LD in the figure, and "width direction" means the direction (left-right direction) indicated by WD in the figure. are orthogonal.

· "Front side" means the side closer to the wearer's skin when worn, and "back side" means the side farther from the wearer's skin when worn.

· "Front" means the side of the member that is closer to the wearer's skin when worn, and "back" means the side that is farther from the wearer's skin when worn.

"Unfolded state" means a flat unfolded state without contraction (including any contraction such as contraction due to elastic members) or slack.

"Elongation rate" means a value when the natural length is taken as 100%. For example, an elongation rate of 200% is synonymous with an elongation ratio of 2 times.

"Artificial urine" contains urea: 2 wt%, sodium chloride: 0.8 wt%, calcium chloride dihydrate: 0.03 wt%, magnesium sulfate heptahydrate: 0.08 wt%, and deionized water: 97 wt%. 09 wt% and used at a temperature of 37°C unless otherwise specified.

"Gel strength" is measured as follows. 1.0 g of superabsorbent polymer is added to 49.0 g of artificial urine and stirred with a stirrer. The resulting gel is left in a thermo-hygrostat at 40° C. and 60% RH for 3 hours, then returned to room temperature, and the gel strength is measured with a card meter (manufactured by I. Techno Engineering: Curdmeter-MAX ME-500).

"Metsuke" is measured as follows. After pre-drying the sample or test piece, it is left in a test room or apparatus under standard conditions (test location: temperature 23±1° C., relative humidity 50±2%) to a constant weight. Pre-drying refers to making a sample or test piece constant weight in an environment at a temperature of 100°C. Fibers with an official moisture content of 0.0% do not need to be pre-dried. Using a sampling template (100 mm x 100 mm), a sample with dimensions of 100 mm x 100 mm is cut from the constant weight specimen. The weight of the sample is measured, multiplied by 100 to calculate the weight per square meter, and used as basis weight.

"Thickness" is automatically measured using an automatic thickness gauge (KES-G5 handy compression tester) under the conditions of a load of 0.098 N/cm ² and a pressurized area of 2 cm ² .

"Water absorption" is measured according to JIS K7223-1996 "Water absorption test method for super absorbent resin".

"Water absorption rate" is defined as "Time to end point" when JIS K7224-1996 "Test method for water absorption rate of superabsorbent polymer" is performed using 2g of superabsorbent polymer and 50g of physiological saline. do.

Unless otherwise specified, the dimensions of each part mean the dimensions in the unfolded state, not in the natural length state.

Unless otherwise specified, the test or measurement shall be conducted in a laboratory or equipment under standard conditions (temperature of 23±1°C, relative humidity of 50±2%). .

The present invention is not limited to tape-type disposable diapers as in the above example, as long as it has riser gathers, and can be used for general disposable diapers such as pad-type and pants-type diapers, as well as other absorbents such as sanitary napkins. It can also be used for sexual goods. Especially for disposable diapers for low birth weight babies, a weak but flexible fit is preferred over a tight fit. Therefore, the riser gathers having the above-described free portion are suitable for disposable diapers for low birth weight infants.

DESCRIPTION OF SYMBOLS 11... Liquid-impermeable sheet 12... Exterior nonwoven fabric 12T... Target part 13... Connection tape 13A... Connection part 30... Top sheet 50... Absorbent element 56... Absorbent body 56n... Constricted part 58... Packaging sheet 60: riser gather, 61: inside elastic member, 62: gathering sheet, 62f: outer layer, 62n: inner layer, 63: gathering elastic member, 64: outside elastic member, 65: root portion, 66: main body Part 67 Front end 68 Middle part 69 Rear end BP Fixed part FP Free part LD Front-back direction M Crotch part WD Width direction.

Claims

an absorber;
A liquid-permeable top sheet arranged on the front side of the absorbent body;
and rising gathers provided on both sides in the width direction of the surface of the top sheet,
The rising gathers are formed by folding back from the root portion attached to the outside in the width direction of an imaginary line continuing in the front-rear direction through the blocking positions on both sides in the width direction of the surface of the top sheet and the inner edge in the width direction of the root portion. a main body extending inward in the width direction without being broken;
The main body portion has a front end and a rear end having a fixed portion fixed to the top sheet, and an intermediate portion located between the front end and the rear end and not fixed to the top sheet. death,
An elongated gathered elastic member extending in the front-rear direction is attached to at least the tip of the intermediate portion,
the intermediate portion is contracted together with the gathers elastic member due to the contraction force of the gathers elastic member, and is expandable together with the gathers elastic member;
A free portion that is not fixed to the top sheet is provided at an inner end portion in the width direction of at least one of the front end portion and the rear end portion so as to continue from the intermediate portion. A fixed portion is provided at the rear end portion other than the free portion,
The width of the free portion is 1/6 to 1/3 of the width of the intermediate portion, and the dimension of the free portion in the front-rear direction is 1 to 9.5 times the width of the free portion.
An absorbent article characterized by:
The width of the free portion is 3.5 mm or more,
The intermediate portion has the gathers elastic member in a distal region with a width equal to the width of the free portion, and does not have the gathers elastic member in a region other than the distal region.
The absorbent article according to claim 1.
An elongated inside elastic member extending in the front-rear direction is provided on the back side of the top sheet in the base portion side region equal to the width of the fixing portion in the region overlapping the back side of the intermediate portion in the unfolded state,
The base-side region is contracted together with the inside elastic member due to the contractile force of the inside elastic member, and is expandable together with the inside elastic member.
3. The absorbent article according to claim 1 or 2.
The absorbent body has a constricted portion narrower in width than both front and rear sides thereof in the middle in the front-rear direction,
The inside elastic member is arranged to pass through the constricted portion,
The absorbent article according to claim 3.
both the front end and the rear end have the free portion;
The width of the free portion of the front end is wider than the width of the free portion of the rear end,
The absorbent article according to any one of claims 1-4.
Disposable diapers for low birth weight babies,
The absorbent article according to any one of claims 1-5.