JP7315360B2 - Pants type disposable wearing article - Google Patents

Description

TECHNICAL FIELD The present invention relates to a disposable wearing article with improved fit to the groin.

A pants-type disposable wearing article is generally provided with an outer body that constitutes at least a waist portion of a front body and a back body, and an inner body that includes an absorbent body that is attached to the outer body so as to extend from the front body to the back body, and that a waist opening and a pair of left and right leg openings are formed by joining both sides of the outer body of the front body and both sides of the outer body of the back body to form side seal portions (see, for example, Patent Document 1).

In such underpants-type disposable wearing articles, it is common to provide an extensible structure in the exterior body in order to improve fit to the body. For example, a waist region defined as a range in the front-rear direction corresponding to the side seal portions and an intermediate region located between the front and rear waist regions have a stretchable structure, which provides a relatively high fit to the body (see Patent Documents 1 to 5, for example).

A representative elastic structure of a pants-type disposable wearing article is provided with elongated elastic members spaced apart from each other along the elastic direction between the overlapping first sheet layer and the second sheet layer. The first sheet layer and the second sheet layer form a planar stretchable region and play the role of covering and hiding the elastic member, and the elastic member built in between the first sheet layer and the second sheet layer plays the role of generating force for elastic stretching. The elastic member is fixed to the first sheet layer and the second sheet layer at least at the portions located at both ends of the elastic region while being stretched in the elastic direction. By this fixation, the elastic member and the first sheet layer and the second sheet layer are integrated, and the first sheet layer and the second sheet layer are contracted by the contractile force of the elastic member to form folds (including wrinkled ones. Formed not only in the natural state but also in the state in which the elastic member is stretched. Hereinafter, simply referred to as folds.). Normally, the first sheet layer and the second sheet layer are unfolded with no folds at the limit of elastic elongation, and the folds are formed as the elastic member shrinks, and the folds are most densely formed in the natural length state.

In such a stretchable structure, if the first sheet layer and the second sheet layer are free from each other, there is a risk that one of the nonwoven fabric layers may partially or wholly float from the other nonwoven fabric layer, causing unnecessary folds or bulges. In addition, in order to create stretchability by the elastic member, the elastic member must extend over the entire stretchable region in the stretchable direction, and at least portions located at both ends of the stretchable region in the stretchable direction must be fixed to the first sheet layer and the second sheet layer, and in the natural state, the first sheet layer and the second sheet layer must be contracted as the elastic member shrinks. That is, it is necessary to bond the first sheet layer and the second sheet layer and to fix the elastic member to the first sheet layer and the second sheet layer.

Currently, hot-melt adhesives are most often the means of choice for securing elastic members to the first and second sheet layers. On the other hand, the bonding between the first sheet layer and the second sheet layer is often performed by welding such as ultrasonic welding in order to reduce the amount of hot melt adhesive used, but the structure performed by hot melt adhesive is also firmly used. In particular, the most representative structure is known as a combined structure that combines the bonding of the first sheet layer and the second sheet layer with the fixing of the elastic member to the first sheet layer and the second sheet layer by bonding the first sheet layer and the second sheet layer via a hot-melt adhesive at the position of the elastic member.

On the other hand, the waist region and the intermediate region overlap with the front-rear region having the absorber, and there is an inner-outer joint for joining the inner body and the outer body in the region. Therefore, even if an elastic member is provided so as to traverse the front-rear direction range having this absorber, its stretching function is limited by the rigidity of the absorber. In addition, the absorbent body may shrink in the width direction, which may deteriorate the feeling of wearing and the appearance of the absorbent body, or the absorbent body may be twisted or cracked, resulting in a decrease in absorption performance.

For this reason, conventionally, an elastic member is continuously attached to the outer body along the width direction, and the stretchability generated by the elastic member is canceled in the portion overlapping the absorbent body, thereby forming a non-stretchable region in the outer body (see, for example, Patent Documents 1 to 6). When fixing the elastic member and joining the first sheet layer and the second sheet layer with a hot-melt adhesive as in the above-described dual-use structure, there are roughly two methods for reducing elasticity.

That is, the first method is a method of finely cutting the portion of the elastic member located in the non-stretchable region. The second method is to form an independently shrinkable portion that is not fixed to the first sheet layer and the second sheet layer or that is weakly fixed to the first sheet layer and the second sheet layer or is weakly fixed with a hot-melt adhesive in a portion located in the non-stretchable region of the elastic member, and that the independently shrinkable portion is cut at one point in the middle in the width direction, and the independently shrinkable portion is shrunk to a natural length or a state close to it without involving the first sheet layer and the second sheet layer. The second method has the advantage of having only one cutting point compared to the first method.

However, conventional pants-type disposable wearing articles have room for improvement in fit to the groin of the wearer.

Japanese Patent Publication No. 2015-512296 Japanese Patent No. 5779738 JP 2015-58061 A JP 2010-029693 A JP 2008-194160 A JP 2012-029806 A

Therefore, the main object of the present invention is to improve the fitting property to the depression of the wearer's groin.

The pants-type disposable wearing article that solves the above problems is as follows.
<First Aspect>
An integrated exterior covering from the front body to the back body, or an exterior body provided separately for the front body and the back body;
an inner body including an absorbent attached to the outer body so as to extend from the front body to the back body;
a side seal portion in which both side portions of the exterior body of the front body and both side portions of the exterior body of the back body are respectively joined;
Equipped with a waist opening and a pair of left and right leg openings,
The exterior body has a non-stretchable region provided in the center in the width direction and a lower waist stretchable region divided into both sides in the width direction by the non-stretchable region in the front-back direction range including the side seal portion and the absorbent body.
The lower waist elastic region incorporates a lower waist elastic member, contracts in the width direction together with the lower waist elastic member, and is expandable in the width direction together with the lower waist elastic member,
Both sides of the inner body are provided with sit-up gathers,
The rising gathers have root portions attached to both sides of the inner body, a body portion extending from the root portions to both sides of the surface of the inner body, a lying portion formed by fixing the front and rear ends of the body portion to the surface of the interior body in a fallen state, a non-fixed rising portion positioned between the front and rear lying portions, and a gathered elastic member provided along at least a tip portion of the rising portion along the front-rear direction,
The rising portion contracts in the front-rear direction together with the gathering elastic member to rise from the surface of the inner body, and is extensible in the front-rear direction together with the gathering elastic member.
In pants-type disposable articles of wear;
At least the end on the crotch side of the lower waist elastic region of the front body is a highly stretched region extending toward the center in the width direction from the rise gathers,
The rising portion and the gathered elastic member extend to the waist opening side to the high stretch region of the front body,
The inner and outer joints that join the inner body and the outer body are provided only in the range from the end of one lower waist stretchable region on the non-stretchable region side to the other end of the lower waist stretchable region on the non-stretchable region side in the front-back direction range having the lower waist stretchable region.
A pants-type disposable wearing article characterized by:

(Effect)
In this pants-type disposable wearing article, since the high stretch region of the lower waist stretchable region exists so as to cross the groove of the groin of the wearer, the outer body can follow the expansion and contraction of the groove of the groin and firmly press the inner body. However, since the high elongation region does not enter the hollow of the groin, simply providing the high elongation region does not sufficiently improve the fit to the hollow of the groin, and there is a risk of creating a gap. Therefore, in the pants-type disposable wearing article, the rising portion of the rising gathers and the gathering elastic member extend to the portion pressed by the high stretch region. Therefore, the portion having the gather elastic member in the rising portion can rise up so as to enter the recess of the groin, based on the highly stretched region that is firmly pressed against the groin. Therefore, in this pants-type disposable wearing article, the fit to the groin is remarkably improved.
It should be noted that it is preferable to limit the width of the inner and outer joints to the same extent as the width of the non-stretchable region, since unnecessary contraction of the absorbent body can be suppressed. Here, if the width of the inner and outer joints is simply narrowed, the inner body tends to move laterally, and the fit to the groin tends to deteriorate. However, in this underpants-type disposable wearing article, the formation of the above-described high stretch region and the positional relationship between the high stretch region and the riser gathers provide an excellent fit to the groin.

<Second Aspect>
The widthwise dimension of the non-stretchable region in the front-back direction range having the high stretching region is less than 1/2 of the widthwise dimension of the absorbent body,
The interval between the rising gathers on both sides is 1/2 to 1 times the dimension in the width direction of the absorbent body.
The pants-type disposable wearing article of the first aspect.

(Effect)
Although the dimensions of each part can be determined as appropriate, it is usually preferable if the dimensions are within the above range because the positional relationship between the high stretch area and the riser gathers is appropriate, and the fit to the groin is particularly good.

<Third Aspect>
The edge of the non-stretchable region side of the lower waist stretchable region of the front body extends stepwise or continuously from the waist opening side toward the crotch side so as to be positioned at the center side in the width direction,
The high stretch region is provided only on the crotch side of the lower waist stretch region of the front body,
A pants-type disposable wearing article according to the first or second aspect.

(Effect)
Inguinal dimples are more pronounced on the crotch side and rarely occur on the waist side. Therefore, it is preferable to prevent shrinkage of the absorbent body in other portions while improving the fitting property to the groin by providing the high elongation region only in the portion of the groin where the depression tends to be deep.

<Fourth Aspect>
The outer body is separately provided on the front body and the back body,
The exterior body of the front body and the exterior body of the back body are spaced apart in the front-rear direction on the crotch side,
The inner body extends in the front-rear direction from the outer body of the front body to the outer body of the back body, and is joined to the outer body of the front body and the outer body of the back body respectively,
The side seal portions are portions where both side portions of the outer body of the front body and both side portions of the outer body of the back body are joined, respectively.
A pants-type disposable wearing article according to any one of aspects 1 to 3.

(Effect)
As a pants-type disposable wearing article, there is known one in which the front exterior body and the rear exterior body are separated from each other in the front-rear direction without being continuous on the crotch side, as in this aspect. Such a two-split type exterior has the advantage that it is not necessary to cut the exterior body to form the leg openings, or even if it is cut, only a small area is required. That is, since the cut-off piece (trim) is discarded, there is an advantage that waste of the material (trim loss) can be suppressed.

However, such a pants-type disposable wearing article with a two-part outer structure inevitably deteriorates the fit around the legs, and is particularly likely to deteriorate the fit around the groin. That is, in the pants-type disposable wearing article of the two-part exterior type, since the distance from the crotch part of the inner body to the crossing position with the outer body is long when worn, the inner body tends to swing left and right around the crossing position as a fulcrum. Also, in the pants-type disposable wearing article of the two-part exterior type, the edge of the crotch side of the exterior body is linear or nearly straight along the width direction, and intersects the side edge of the interior body at a right angle or at an angle similar thereto. These mean that a pants-type disposable wearing article with a two-piece exterior tends to lack fit to the groin.

Therefore, the above-described formation of the high-stretch region and the positional relationship between the high-stretch region and the riser gathers are of great technical significance when applied to such a pants-type disposable wearing article with a two-part exterior.

<Fifth Aspect>
On both sides of the inner body, side flaps extending laterally beyond the rising gathers extend in the front-rear direction from the front exterior body to the rear exterior body,
The side flap has a side elastic region that elastically expands and contracts in the front-rear direction,
The side stretchable region incorporates a side elastic member, contracts in the front-rear direction together with the side elastic member, and is expandable in the front-rear direction together with the side elastic member,
The side elastic regions extend to the waist opening side to the high stretch region of the front body,
The pants-type disposable wearing article of the fourth aspect.

(Effect)
As described above, in the pants-type disposable wearing article whose exterior is divided into two parts, the inner body is not only easy to move in the lateral direction, but also crosses the side edges of the inner body at a right angle or at an angle close thereto, so the area covering the groin is inevitably small. On the other hand, when the side flaps and the side stretchable regions are provided as in this aspect, the side stretchable regions elastically support the lateral movement of the interior body, and the side stretchable regions cover the sides of the interior body, thereby making it difficult for gaps to occur on the sides of the interior body.

According to the present invention, advantages such as an improved fit to the groin dimple of the wearer are provided.

Fig. 2 is a plan view showing the inner surface of the underpants-type disposable diaper in an unfolded state; Fig. 2 is a plan view showing the outer surface of the pants-type disposable diaper in an unfolded state; FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1; 3 is a cross-sectional view taken along line 3-3 of FIG. 1; FIG. (a) 4-4 cross-sectional view of FIG. 1, and (b) 5-5 cross-sectional view of FIG. 1 is a perspective view of a pants-type disposable diaper; FIG. FIG. 4 is a plan view showing the outer surface of the inner body in the unfolded state together with the outline of the outer body; 4 is a sectional view of another example corresponding to section 4-4 of FIG. 1; FIG. FIG. 2 is a cross-sectional view of another example corresponding to the 2-2 cross section of FIG. 1; FIG. 3 is a cross-sectional view of another example corresponding to the 3-3 cross section of FIG. 1; FIG. 4 is an enlarged view of a main portion of FIG. 3; FIG. 10 is an enlarged view of a main portion of FIG. 9; 4 is an enlarged plan view of the front exterior body; FIG. It is an enlarged plan view of a back exterior body. 4 is an enlarged plan view of the front exterior body; FIG. It is an enlarged plan view of a back exterior body. 4 is an enlarged plan view of the front exterior body; FIG. It is an enlarged plan view of a back exterior body. 1 is a perspective view of a cutting device; FIG. FIG. 4 is an enlarged plan view of a non-stretchable area portion;

Hereinafter, as an example of a pants-type disposable wearing article, a pants-type disposable diaper will be described in detail with reference to the accompanying drawings. The dot-patterned portion in the cross-sectional view indicates the adhesive as a joining means for joining each component located on the front side and the back side thereof, and is formed by solid, bead, curtain, summit, or spiral coating of hot melt adhesive, or pattern coating (transfer of hot melt adhesive by letterpress method), etc. Alternatively, or together with this, the fixed portion of the elastic member is formed by coating the outer peripheral surface of the elastic member such as comb gun or Surewrap coating. 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 joining means for joining each constituent member, a means by material welding such as heat sealing or ultrasonic sealing can be used.

1 to 6 show an example of a pants-type disposable diaper. This underpants-type disposable diaper comprises a rectangular front exterior body 12F constituting at least the waist circumference of the front body F, a rectangular rear exterior body 12B constituting at least the waist circumference of the back body B, and an inner body 200 provided inside the exterior bodies 12F and 12B so as to extend from the front exterior body 12F to the rear exterior body 12B through the crotch part. Both sides of the front exterior body 12F and both sides of the rear exterior body 12B are joined to form a side seal portion 12A, whereby the opening formed by the front and rear ends of the exterior bodies 12F and 12B serves as a waist opening WO through which the wearer's torso passes, and the portions surrounded by the lower edges of the exterior bodies 12F and 12B and the side edges of the interior body 200 on both sides in the width direction of the interior body 200 serve as leg openings LO through which the legs pass. The inner body 200 is a part that absorbs and holds excrement such as urine, and the outer bodies 12F and 12B are parts that support the inner body 200 against the wearer's body. Symbol Y indicates the total length of the diaper in the unfolded state (length in the front-rear direction from the edge of the waist opening WO of the front body F to the edge of the waist opening WO of the back body B), and symbol X indicates the total width of the diaper in the unfolded state.

This pants-type disposable diaper has a waist region T defined as a front-back direction range having side seal portions 12A (a front-back direction range from the waist opening WO to the upper ends of the leg openings LO), and an intermediate region L defined as a front-back direction range (between the front-back region having the side seal portions 12A of the front body F and the front-back direction region having the side seal portions 12A of the back body B) forming the leg openings LO. The waist region T can be divided into a “waist portion” W conceptually forming the edge of the waist opening and a “lower waist portion” U below this. Usually, when the waist area T has a boundary where the elastic stress in the width direction WD changes (for example, the thickness or the elongation rate of the elastic member changes), the waist portion W is closer to the waist opening WO than the boundary closest to the waist opening WO side. The length in the front-rear direction differs depending on the size of the product and can be determined as appropriate. For example, the waist portion W can be 15 to 40 mm, and the lower waist portion U can be 65 to 120 mm. On the other hand, both side edges of the intermediate region L are constricted in a U-shape or curvilinear shape along the circumference of the wearer's leg, and this is a portion into which the wearer's leg is inserted. As a result, the unfolded pants-type disposable diaper has a substantially hourglass shape as a whole.

(inner body)
The inner body 200 can take any shape, but is rectangular in the illustrated example. As shown in FIGS. 3 to 5, the inner body 200 includes a body-side top sheet 30, a liquid-impermeable sheet 11, and an absorbent element 50 interposed therebetween. Reference numeral 40 denotes an intermediate sheet (second sheet) provided between the top sheet 30 and the absorbent element 50 in order to quickly transfer the liquid permeating through the top sheet 30 to the absorbent element 50. Reference numeral 60 denotes rise gathers 60 extending from both sides of the inner body 200 so as to come in contact with the legs of the wearer in order to prevent leakage of excrement to both sides of the inner body 200.

(top sheet)
The top sheet 30 has the property of being permeable to liquid, and examples thereof include perforated or non-perforated nonwoven fabrics and porous plastic sheets. Further, the top sheet 30 may be composed of one sheet, or may be composed of a laminated sheet obtained by laminating two or more sheets. Similarly, the top sheet 30 may consist of one sheet or two or more sheets in the planar direction.

Both sides of the top sheet 30 may be folded back at the side edges of the absorbent element 50 , or may protrude laterally from the side edges of the absorbent element 50 without being folded.

The top sheet 30 is desirably fixed to a member adjacent to the back side by means of material welding such as heat sealing or ultrasonic sealing, or hot-melt adhesive for the purpose of preventing misalignment with respect to the member on the back side. In the illustrated example, the top sheet 30 is fixed to the surface of the intermediate sheet 40 and the surface of the portion of the packaging sheet 58 located on the front side of the absorbent body 56 with a hot-melt adhesive applied to its back surface.

(intermediate sheet)
An intermediate sheet (also called a “second sheet”) 40 having a faster liquid permeation rate than the top sheet 30 can be provided in order to quickly transfer the liquid that has permeated the top sheet 30 to the absorbent body. The intermediate sheet 40 is intended to quickly transfer the liquid to the absorbent body to enhance the absorption performance of the absorbent body, and to prevent the "return" phenomenon of the absorbed liquid from the absorbent body. The intermediate sheet 40 can also be omitted.

Examples of the intermediate sheet 40 include materials similar to those of the top sheet 30, spunlace nonwoven fabric, spunbond nonwoven fabric, SMS nonwoven fabric, pulp nonwoven fabric, mixed sheet of pulp and rayon, pointbond nonwoven fabric, and crepe paper. In particular, an air-through nonwoven fabric is preferred because it is bulky. 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 40 in the illustrated example is shorter than the width of the absorbent body 56 and arranged in the center, but it may be provided over the entire width. The length of the intermediate sheet 40 in the front-rear direction may be the same as the full length of the diaper, the length of the absorbent element 50, or within a short length range centered on the liquid-receiving area.

The intermediate sheet 40 is desirably fixed to a member adjacent to the back side by means of material welding such as heat sealing or ultrasonic sealing, or hot-melt adhesive for the purpose of preventing misalignment with respect to the member on the back side. In the illustrated example, the intermediate sheet 40 is fixed to the surface of the portion of the packaging sheet 58 located on the front side of the absorbent body 56 with a hot-melt adhesive applied to its back surface.

(liquid-impermeable sheet)
The material of the liquid-impermeable sheet 11 is not particularly limited, but examples thereof include a plastic film made of an olefin resin such as polyethylene or polypropylene, a laminated nonwoven fabric in which a plastic film is provided on the surface of a nonwoven fabric, and a laminated sheet in which a nonwoven fabric or the like is laminated and bonded to a plastic film. For the liquid-impermeable sheet 11, it is preferable to use a liquid-impermeable and moisture-permeable material that is preferably used from the viewpoint of preventing stuffiness. As a plastic film having moisture permeability, a microporous plastic film obtained by kneading an inorganic filler into an olefin resin such as polyethylene or polypropylene, forming a sheet, and stretching the sheet in a uniaxial or biaxial direction is widely used. In addition to this, a non-woven fabric using microdenier fibers, a method such as enhancing leakage prevention by reducing the voids in the fibers by applying heat or pressure, or coating with a super absorbent resin or hydrophobic resin or a water repellent agent. A liquid-impermeable sheet can also be used as the liquid-impermeable sheet 11 without using a plastic film.

The liquid-impermeable sheet 11 has a width that can be accommodated on the back side of the absorbent element 50 as shown in the figure, and can also be wrapped around both sides of the absorbent element 50 to extend to both sides of the top sheet 30 of the absorbent element 50 in order to improve leakproofness. It is appropriate that the width of this extended portion is about 5 to 20 mm on each side.

(absorbing element)
The absorbent element 50 has an absorbent body 56 and a wrapping sheet 58 that wraps the entire absorbent body 56 . The packaging sheet 58 can also be omitted.

(Absorber)
Absorbent body 56 can be formed from an aggregate of fibers. As the fiber aggregate, a filament aggregate obtained by piling short fibers such as cotton pulp and synthetic fibers, or by opening a tow (fiber bundle) of synthetic fibers such as cellulose acetate as necessary, can be used. The fiber basis weight can be, for example, about 100 to 300 g/m ² in the case of laminating cotton pulp or short fibers, and can be, for example, about 30 to 120 g/m ² in the case of a filament assembly. 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. It is preferable to disperse and hold superabsorbent polymer particles in the absorbent body 56 .

Although the absorbent body 56 may be rectangular, as shown in FIG. 7, etc., it is preferable to have an hourglass shape with a constricted portion 56N narrower in width than both front and rear sides in the middle in the front-rear direction, because the fit of the absorbent body 56 itself and the sit-up gathers 60 around the legs is improved.

Also, the dimensions of the absorbent body 56 can be appropriately determined as long as they cover the front, rear, left, and right of the urination opening position, but preferably extend to the peripheral edge of the inner body 200 or its vicinity in the front-back direction LD and width direction WD. The reference numeral 56X indicates the full width of the absorber 56. As shown in FIG.

(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 disposable diaper can be used as they are. For example, after sieving with a standard sieve of 500 μm (JIS Z8801-1:2006) (shaking for 5 minutes), it is desirable that the percentage of particles remaining on the sieve is 30% by weight or less, and sieving with a standard sieve of 180 μm (JIS Z8801-1:2006) (shaking for 5 minutes). It is desirable that the ratio of particles remaining on the sieve is 60% by weight or more.

Materials for the superabsorbent polymer particles may be used without any particular limitation, but those having a water absorption of 40 g/g or more are suitable. Examples of superabsorbent polymer particles include starch-based, cellulose-based, and synthetic polymer-based particles, and starch-acrylic acid (salt) graft copolymers, starch-acrylonitrile copolymer saponified products, crosslinked products of sodium carboxymethyl cellulose, acrylic acid (salt) polymers, and the like 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 having 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.

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 50 to 350 g/m ² . If the basis weight of the polymer is less than 50 g/m ² , it becomes difficult to secure the absorption capacity. Above 350 g/m ² , the effect saturates.

(packaging sheet)
When the packaging sheet 58 is used, tissue paper, especially crepe paper, non-woven fabric, poly-laminated non-woven fabric, a perforated sheet, or the like can be used as the material. 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 SMS non-woven fabric (SMS, SSMMS, etc.) is particularly suitable, and its material can be polypropylene, polyethylene/polypropylene composite, or the like. The basis weight is preferably 5 to 40 g/m ² , particularly 10 to 30 g/m ² .

The packaging structure of the packaging sheet 58 can be determined as appropriate, but from the viewpoint of ease of manufacture and prevention of leakage of the superabsorbent polymer particles from the front and back edges, it is preferable to wind the absorbent body 56 in a cylindrical shape so as to surround the front and back surfaces and both side surfaces, protrude the front and rear edges from the front and back of the absorbent body 56, and join the overlapping parts and the overlapping parts of the front and rear protruding parts by a joining means such as hot melt adhesive or material welding.

(Getting up gathers)
The rising gather 60 has a rising part 68 rising from the side part of the inner body 200, and the rising part 68 contacts the wearer's groin to the buttocks through the circumference of the leg to prevent side leakage. In the illustrated example of the rising gathers 60, the root side portion 60B stands obliquely toward the center in the width direction, and the front end portion 60A from the intermediate portion stands obliquely toward the outside in the width direction.

More specifically, the riser gathers 60 of the illustrated example are formed by folding a band-shaped gather sheet 62 having a length equal to the length of the inner body 200 in the front-rear direction in the width direction WD at the leading end portion to fold it in two, and fixing a plurality of slender gather elastic members 63 between the folded portion and the sheet in the vicinity thereof in a longitudinally stretched state at intervals in the width direction WD. A base end portion of the rising gathers 60 located on the opposite side to the tip portion (the end portion opposite to the sheet folded portion in the width direction WD) is a root portion 65 fixed to the side portion of the interior body 200 on the back side of the liquid impermeable sheet 11, and the portion other than the root portion 65 is a body portion 66 (portion on the folded portion side) extending from the root portion 65. Further, the body portion 66 has a root side portion 60B extending toward the center in the width direction, and a distal end portion 60A that is folded back at the tip of the root side portion 60B and extends outward in the width direction. Both ends of the main body portion 66 in the front-rear direction are laid down portions 67 that are fixed to the side surfaces of the top sheet 30 in the laid-down state, while the front-rear direction middle portion positioned between them is a non-fixed rising portion 68. A gather elastic member 63 along the front-rear direction LD is fixed in a stretched state to at least the tip portion of the rising portion 68.

In the riser gathers 60 constructed as described above, the contraction force of the gather elastic members 63 causes the riser portions 68 to rise so as to come into contact with the skin as indicated by arrows in FIG. In particular, when the root part 65 is positioned on the back side of the inner body 200, the rising part 68 rises so as to open outward in the width direction in the crotch part and its vicinity, so that the rising gathers 60 come to contact the circumference of the leg with a surface, improving the fit. The root portion 65 can also be fixed to the front side of the inner body 200 , for example, the surfaces of both sides of the top sheet 30 .

Like the rising gathers 60 in the illustrated example, in a bending structure in which the main body portion 66 is composed of a root side portion 60B extending toward the center in the width direction and a distal end portion 60A that is folded back at the tip of the root side portion 60B and extends outward in the width direction, the tip side portion 60A and the root side portion 60B are joined in the laid down state, and the root side portion 60B is joined to the top sheet 30 in the laid down state. At least one of hot-melt adhesives by various application methods and material welding means such as heat sealing and ultrasonic sealing can be used to join the facing surfaces in the lodging portion 67 . In this case, the bonding of the root side portion 60B and the top sheet 30 and the bonding of the tip side portion 60A and the root side portion 60B may be performed by the same means or by different means. For example, it is preferable to join the root side portion 60B and the top sheet 30 with a hot melt adhesive, and join the tip side portion 60A and the root side portion 60B by material welding.

As the gather sheet 62, spunbond nonwoven fabrics (SS, SSS, etc.), SMS nonwoven fabrics (SMS, SSMMS, etc.), soft nonwoven fabrics with excellent uniformity and hiding properties such as meltblown nonwoven fabrics, and optionally water-repellent treated with silicone or the like can be suitably used. In this case, the fiber weight of the nonwoven fabric is preferably about 10 to 30 g/m ² . A thread rubber or the like can be used as the gather elastic member 63 . When spandex thread rubber is used, the thickness is preferably 470 to 1240 dtex, more preferably 620 to 940 dtex. The elongation rate of the gathered elastic member 63 in the attached state is preferably 150 to 350%, more preferably 200 to 300%. The number of gather elastic members 63 is preferably 2-6, more preferably 3-5. An appropriate interval between the gathered elastic members 63 is 3 to 10 mm. With this configuration, the area in which the gather elastic member 63 is arranged can easily come into contact with the skin. The gather elastic member 63 may be arranged not only on the tip side but also on the base side.

At the rising portion 68 of the rising gather 60, at least one of hot-melt adhesive by various coating methods and fixing means by material welding such as heat sealing and ultrasonic sealing can be used for bonding the inner layer and the outer layer of the gather sheet 62 and fixing the gathered elastic member 63 sandwiched between them. If the inner layer and the outer layer of the gather sheet 62 are entirely adhered together, the flexibility is impaired. Therefore, it is preferable that the gather elastic member 63 is not adhered or adhered weakly except for the adhered portion. In the illustrated example, the hot-melt adhesive is applied only to the outer peripheral surface of the gathers elastic member 63 by an application means such as a comb gun or a sure wrap nozzle, and is sandwiched between the inner layer and the outer layer of the gathers sheet 62, thereby fixing the gathers elastic member 63 to the inner layer and the outer layer of the gathers sheet 62 and fixing the inner layer and the outer layer of the gathers sheet 62 only with the hot-melt adhesive applied to the outer peripheral surface of the gathers elastic member 63.

Similarly, for fixing the lodging portion 67, it is possible to use at least one of hot-melt adhesives by various application methods and material welding means such as heat sealing and ultrasonic sealing.

(side flap)
Both sides of the inner body 200 are provided with side flaps 70 extending to the sides of the absorbent body 56. Preferably, the side flaps 70 are formed with side stretchable regions SG that stretch in the front-rear direction. The illustrated side flap 70 has one or more elongated side elastic members 73 provided along the front-rear direction LD and spaced apart from each other, a first sheet layer 71 facing the outside of the side elastic member 73, and a second sheet layer 72 facing the inside of the side elastic member 73.

The sheet material that forms the first sheet layer 71 and the second sheet layer 72 is not particularly limited, and an appropriate nonwoven fabric such as the nonwoven fabric that can be used for the above-described rising gathers 60 and the above-described exterior bodies 12F and 12B can be selected. In the examples shown in FIGS. 3, 4 and 11, the first sheet layer 71 and the second sheet layer 72 are formed by extending the gather sheet 62 of the rising gather 60 as will be described later. As shown in FIGS. 9, 10 and 12, the side flaps 70 may be constructed by adding a dedicated sheet material 79 separate from the rising gathers 60. FIG. In the former case, the front and rear ends of the side flaps 70 coincide with the front and rear ends of the riser gathers 60 (that is, in this case, the front and rear ends of the inner body 200), but in the latter case, the front and rear ends of the side flaps 70 may be positioned closer to the center in the front-rear direction than the front and rear ends of the riser gathers 60.

The side elastic member 73 is also not particularly limited, and an elongated elastic member similar to the gather elastic member 63 described above can be used. The elongation rate of the side elastic members 73 in the attached state is preferably 150 to 350%, more preferably 200 to 270%. The number of side elastic members 73 is preferably 2-16, more preferably 6-10. An appropriate spacing between the side elastic members 73 is 5 to 10 mm.

The side elastic members 73 are fixed to the first sheet layer 71 and the second sheet layer 72 . For bonding the first sheet layer 71 and the second sheet layer 72 and fixing the side elastic member 73 sandwiched between them, hot-melt adhesive HM by various coating methods, and fixing means by material welding such as heat sealing and ultrasonic sealing can be used. If the bonding area between the first sheet layer 71 and the second sheet layer 72 is large, the flexibility is impaired. Therefore, it is preferable that the side elastic members 73 are not bonded or are weakly bonded. In the illustrated example, the side elastic member 73 is fixed to the first sheet layer 71 and the second sheet layer 72 and fixed between the first sheet layer 71 and the second sheet layer 72 only with the hot melt adhesive HM applied to the outer peripheral surface of the side elastic member 73 by applying the hot melt adhesive HM only to the outer peripheral surface of the side elastic member 73 by applying means such as a comb gun or a sure wrap nozzle and sandwiching the side elastic member 73 between the first sheet layer 71 and the second sheet layer 72 . It has become.

The attachment range of the side elastic member 73 in the front-rear direction, that is, the range in the front-rear direction in which the side stretchable region SG is formed can be determined as appropriate, but it is preferably the same as or wider than the range in the front-rear direction of the non-joint portion 77, which will be described later. In addition, it is preferable that the range in the front-rear direction of the side stretchable region SG is the same as the contracted portion of the gathering elastic member of the sit-up gather or extends in the front-rear direction more than that.

The side flap 70 has three or more sheet layers including a first sheet layer 71 and a second sheet layer 72 . That is, in addition to the innermost sheet layer 74 and the outermost sheet layer 75, there is at least one inner sheet layer 76 positioned therebetween. Some or all of these sheet layers may be formed of separate sheet materials, or may be formed by folding one sheet material once or several times. The internal sheet layer 76 can be appropriately selected from the aforementioned gathered sheet 62, the liquid-impermeable sheet 11, or the same non-woven fabric as the exterior bodies 12F and 12B described later, and can be formed by appropriately extending or folding the aforementioned gathered sheet 62 or the liquid-impermeable sheet 11.

Preferably, the side flaps 70 have non-bonded portions 77 where at least one of the innermost sheet layer 74 and the outermost sheet layer 75 is not bonded to the inner sheet layer 76 that lies behind it. In addition, the non-bonded portion 77 is a portion that continues continuously or intermittently in the front-rear direction LD within the range in the width direction WD including the region between the side elastic member 73 positioned most laterally and the side edge of the side flap 70 . In other words, as long as the unbonded portion 77 is unbonded between either the innermost sheet layer 74 or the outermost sheet layer 75 and the inner sheet layer 76 that overlies the innermost sheet layer 74, the other part or all of the layers may be bonded, or all the sheet layers in the thickness direction may be unbonded. For example, in the non-bonded portion 77 shown in FIGS. 3, 4, and 11, the non-bonded portion between the innermost sheet layer 74 and the inner sheet layer 76 overlapping the innermost sheet layer 74 extends from the side edge to the fixing position of the side elastic member on the most lateral side, and the non-bonded portion between the outermost sheet layer 75 and the inner sheet layer 76 overlapping the inner sheet layer 76 extends further to the center side in the width direction. 9, 10 and 12, the non-bonded portion between the innermost sheet layer 74 and the inner sheet layer 76 overlapping the innermost sheet layer 74 and the non-bonded portion between the outermost sheet layer 75 and the inner sheet layer 76 overlapping the outermost sheet layer 75 continue from the side edge to the center side in the width direction from the fixing position of the side elastic member closest to the side edge, but the former continues to the center side in the width direction.

The dimension of the non-joint portion 77 in the width direction WD can be appropriately determined, but is preferably 2 to 15 mm, particularly preferably 5 to 10 mm. In addition, it is preferable that the dimension of the non-bonded portion 77 in the front-rear direction LD is 30% or more, particularly 40% or more of the total length Y of the product. Moreover, in the case of a pants-type disposable wearing article in which the front exterior body 12F and the rear exterior body 12B are separated from each other as in the illustrated example, the non-joint portion 77 preferably extends to a position overlapping the front exterior body 12F and the rear exterior body 12B. In this case, the non-joint portion 77 preferably extends over the entire front-rear direction LD of the interior body 200 . The non-joint portion 77 preferably extends only to a position between the front and rear edges of the interior body 200 and the elastic members 16 and 19 of the front exterior body 12F and the rear exterior body 12B closest to the leg openings LO. Furthermore, the non-joint portion 77 may extend only to a position between the elastic members 16 and 19 closest to the leg opening LO in the front exterior body 12F and the rear exterior body 12B and the edge of the leg opening LO (the rear edge of the front exterior body 12F and the front edge of the rear exterior body 12B).

Also, the gap between at least one of the innermost sheet layer 74 and the outermost sheet layer 75 and the inner sheet layer 76 overlapping the back thereof is closed on both sides in the width direction WD of the non-bonded portion 77 . As shown in the illustrated example, one side of the gap of the non-bonded portion 77 can be closed by folding back the sheet material forming the innermost sheet layer 74 or the outermost sheet layer 75 at the side edge of the side flap 70, and the other side can be closed by joining the sheet layers adjacent in the thickness direction at appropriate locations using hot melt adhesive HM, welding means, or the like. Of course, both sides of the gap of the non-bonded portion 77 can also be closed in the same way, for example by folding back the sheet material or by the hot-melt adhesive HM.

In this underpants-type disposable diaper, the side flaps 70 contract in the front-rear direction LD as the side elastic members 73 contract, and as shown in FIG. In other words, the folds of the side stretchable regions SG are formed side by side in the front-rear direction LD in the portions of the side flaps 70 that include the non-bonded portions 77 . Here, the non-bonded portion 77 is a portion where at least one of the innermost sheet layer 74 and the outermost sheet layer 75 is not bonded to the inner sheet layer 76 overlapping the back thereof, and the gap between the sheet layers is closed on both sides in the width direction WD of the non-bonded portion 77. In addition, the non-bonded portion 77 continues in the front-rear direction LD in a width direction WD range including a region between the side elastic member 73 positioned most laterally and the side edge of the intermediate region L (a width direction WD range equal to or greater than that region). In other words, the hollow portion surrounded by the sheet layer continues to the non-bonded portion 77 in the front-rear direction LD. As a result, the folds formed in the non-bonded portion 77 are formed by greatly expanding at least one of the innermost sheet layer 74 and the outermost sheet layer 75, and are large and soft (that is, have excellent cushioning properties). Therefore, the large and soft folds are formed on the inner side, the outer side, both the inner and outer sides, or the entire thickness direction of the range including the side edges of the side flaps 70, so that the end portions of the leg openings LO are pleasant to the touch.

The side elastic members 73 may be positioned near the side edges of the side flaps 70, but the portion of the side flaps 70 extending from the side edges to the central side in the width direction WD by 2 to 15 mm (especially 5 to 10 mm) preferably does not include the side elastic members 73 and includes part or all of the non-bonded portion 77. In this way, when the side elastic members 73 are sufficiently spaced from the side edges of the side flaps 70, and part or all of the non-bonded portions 77 are included in the spaced portions, large folds rich in flexibility and cushioning are formed in the entire lateral thickness direction of the portions (that is, the portions having the side elastic members 73) that are pressed against the skin when the product is held or worn when the product is worn or worn.

Although the positional relationship between the non-joint portion 77 and the side elastic member 73 can be determined as appropriate, it is preferable to have at least one side elastic member 73 at a position that overlaps the non-joint portion 77 in the thickness direction, as in the illustrated example, because the contractile force of the side elastic member 73 is directly applied to the non-joint portion 77, and the shape retention of the folds in the non-joint portion 77 is high.

In the non-bonded portion 77, the inner sheet layer 76 that overlies the innermost sheet layer 74 or the outermost sheet layer 75 may be fixed to the adjacent sheet layer on the opposite side as shown in FIG. As a result, folds are independently formed also in the inner sheet layer 76 by the contractile force of the side elastic members 73 . In other words, the greatly swollen folds formed in the side flaps 70 are supported by the folds of the inner sheet layer 76 independently formed on the inner side thereof, so that the folds having better cushioning properties are formed in the side flaps 70. - 特許庁

As shown in the illustrated example, the side flap 70 has a folded sheet layer that is folded back at the side edge of the side flap 70, and at least one of the innermost sheet layer 74 and the outermost sheet layer 75 of the side flap 70 is preferably a portion on one side across the folding position of the folded sheet layer, because the cushioning properties of the folds formed in the non-bonded portion 77 are particularly improved due to the restoring force against folding. A folded sheet layer means a pair of layers formed by folding a sheet material.

One preferred example is the structure shown in FIG. The side flaps 70 have double folded sheet layers that are folded back at their side edges. The innermost sheet layer 74 and the outermost sheet layer 75 of the non-joint part 77 are respectively an inner part and an outer part across the folding position of the folded sheet layer located outside, and the inner sheet layer 76 includes an inner part and an outer part across the folding position of the folded sheet layer located inside. The first sheet layer 71 and the second sheet layer 72 each include an inner portion sandwiching the folding position of the folded sheet layer positioned inside and an inner portion sandwiching the folding position of the folded sheet layer positioned outside . Further, the non-joint part 77 includes an outside part across the folding position of the folding sheet layer positioned outside and a part outside the folding position of the folding sheet layer positioned inside, which are not joined. In this structure, by arranging the double folded sheet layers, two sheet layers other than the first sheet layer 71 and the second sheet layer 72 can be formed, and each layer has a restoring force against folding, so that the side flaps 70 can be formed with pleats having excellent cushioning properties with less sheet materials.

Another preferred example is the structure shown in FIG. The side flap 70 has double folding sheet layers folded back at the side edges thereof, and the first sheet layer 71 and the second sheet layer 72 each include a portion on one side and a portion on the other side across the folding position of the folding sheet layer positioned inside (that is, both the first sheet layer 71 and the second sheet layer 72 are the internal sheet layers 76). In addition, the innermost sheet layer 74 and the outermost sheet layer 75 in the non-bonded portion 77 are the portions on one side and the other side with respect to the folding position of the outer folded sheet layer, respectively. The non-joint part 77 is a part where the innermost sheet layer 74 and the first sheet layer 71 overlapping the back thereof are not joined, and a part where the outermost sheet layer 75 and the second sheet layer 72 overlapping the back thereof are not joined. In this structure, the folds formed in the non-joint portion 77 are formed at least on both the inner and outer sides of the range including the side edges of the intermediate region L, so that the inner and outer surfaces of the end of the leg opening LO are comfortable to the touch. In addition, since the innermost sheet layer 74 and the outermost sheet layer 75 are the portions on one side and the other side with respect to the folding position of the folded sheet layer located outside, the folds formed in the non-joint portions 77 have particularly high cushioning properties due to the restoring force against folding.

As in these examples, when the non-joint portion 77 has a four-layer structure, it is preferable to construct the side flaps 70 using the sheet of the rising gathers 60 as in the example shown in FIG. 11 . That is, the folding sheet layer of the side flaps 70 described above can be formed by a first portion P1 formed by extending the two-layer structure of the sheet of the rising gathers 60 from the starting point of the rising gathers 60 to the side edge of the side flaps 70, and a second portion P2 of the two-layer structure of the sheets of the rising gathers 60 being folded back at the side edges of the side flaps 70 and extending toward the center in the width direction WD.

(Exterior body)
The exterior bodies 12F and 12B are composed of a rectangular front exterior body 12F that constitutes at least the waist circumference of the front body F, and a rectangular rear exterior body 12B that constitutes at least the waist circumference of the back body B. The front exterior body 12F and the rear exterior body 12B are not continuous on the crotch side and are spaced apart in the front-rear direction LD (exterior halves type). This separation distance in the front-rear direction can be set to about 40 to 60% of the total length Y, for example. In the illustrated example, the lower edges of the front exterior body 12F and the rear exterior body 12B are linear along the width direction WD, but the lower edge of at least one of the front exterior body 12F and the rear exterior body 12B may be curved along the circumference of the leg. Alternatively, as shown in FIG. 8, the outer body 12 may be an integral body extending from the front body F to the back body B through the crotch (exterior integrated type).

The outer bodies 12F and 12B have a waist portion corresponding to the waist region T in the front-rear direction. Further, in this example, the rear exterior body 12B has a longer dimension in the front-rear direction than the front exterior body 12F, and the front exterior body 12F does not have a portion corresponding to the intermediate region L, but the rear exterior body 12B has a buttock cover portion C extending from the waist region T toward the intermediate region L side. Although not shown, the front exterior body 12F may also be provided with an inguinal cover portion extending from the waist region T to the intermediate region L side, a structure may be provided in which the groin cover portion is provided but the buttocks cover portion is not provided, or a portion corresponding to the intermediate region L may not be provided in both the front exterior body 12F and the rear exterior body 12B.

As shown in FIGS. 4 and 5, the exterior bodies 12F and 12B have an inner sheet layer 12H, an outer sheet layer 12S, and elastic members 15-19 provided therebetween. Each sheet layer may be a single common sheet material, or may be individual sheet materials. That is, in the former case, the elastic members 15 to 19 can be provided between the inner portion and the outer portion of a single sheet material folded back at appropriate positions such as the edge of the waist opening WO and the edge on the side of the leg opening LO in part or all of the exterior body. In the illustrated example, the waist portion W has a portion including the folded portion of the sheet material. For example, in the waist portion W, the sheet material forming the outer sheet layer 12S extends only to the edge of the waist opening WO, but the sheet material forming the inner sheet layer 12H is folded around the edge of the sheet material forming the second sheet layer on the waist side and folded inside. Further, this folded portion serves as an interior cover layer 12r that extends over the entire width direction of the exterior body to a position where it overlaps the end of the interior body 200 on the side of the waist opening WO. The inner cover layer 12r may not be formed by folding the sheet material forming the inner sheet layer 12H, but may be formed by attaching a dedicated sheet material.

Elastic members 15 to 19 are built in the outer bodies 12F and 12B in order to improve the fit around the waist of the wearer, and an elastic region A2 is formed that elastically expands and contracts in the width direction WD with the expansion and contraction of the elastic members. In this stretchable region A2, the exterior bodies 12F and 12B shrink with the shrinkage of the elastic members in the state of natural length, and wrinkles or folds are formed. As the elastic members 15 to 19, in addition to elongated elastic members such as thread rubber (illustrated example), well-known elastic members such as band-like, mesh-like, and film-like elastic members can be used without particular limitation. As the elastic members 15 to 19, synthetic rubber or natural rubber may be used.

To explain the elastic members 15 to 19 in the illustrated example in more detail, a plurality of waist elastic members 17 are attached to the waist portions W of the outer bodies 12F and 12B at intervals in the front-rear direction so as to be continuous over the entire width direction WD. In addition, one or more of the waist elastic members 17 disposed in the region adjacent to the lower waist portion U may overlap the inner body 200, or may be provided on both sides in the width direction except for the central portion in the width direction overlapping the inner body 200. As the waist elastic member 17, about 2 to 15, particularly about 4 to 10 rubber threads having a thickness of 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber, in the case of natural rubber, a cross-sectional area of 0.05 to 1.5 mm ² , particularly about 0.1 to 1.0 mm ² ) are preferably provided at intervals of 2 to 12 mm, especially 3 to 7 mm. The elongation rate in the width direction WD is preferably about 150 to 400%, particularly about 220 to 320%. In addition, the waist part W does not need to use the waist elastic member 17 with the same thickness or the same elongation rate in all of the front and back direction LD, and for example, the thickness and elongation rate of the elastic member 17 may be different between the upper part and the lower part of the waist part W.

Moreover, it is preferable that a plurality of waist lower elastic members 15 and 19 made of elongated elastic members are attached to the lower waist portions U of the outer bodies 12F and 12B with a space therebetween in the front-rear direction. As the waist lower elastic members 15 and 19, it is preferable to provide about 5 to 30 thread rubbers having a thickness of 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber, in the case of natural rubber, a cross-sectional area of 0.05 to 1.5 mm ² , particularly about 0.1 to 1.0 mm ² ) at intervals of 1 to 15 mm, particularly 3 to 8 mm, thereby extending the lower waist portion U in the width direction WD. The ratio is preferably about 200-350%, more preferably about 240-300%.

Moreover, it is preferable that a cover section elastic member 16 made of an elongated elastic member is attached to the buttock cover section C of the back exterior body 12B. The buttock cover portion C is contracted toward the center in the width direction WD by the cover portion elastic member 16 . As the cover section elastic member 16, it is preferable to provide a thread rubber having a thickness of 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber; in the case of natural rubber, the cross-sectional area is 0.05 to 1.5 mm ² , particularly about 0.1 to 1.0 mm ² ). is preferred.

On the other hand, when the front exterior body 12F is provided with an inguinal cover portion, a cover elastic member can be provided in the same manner as the buttock cover portion C is provided.

When the elastic members 15, 16, 19 are provided in the front-back direction range having the absorbent body 56, as in the illustrated example of the lower waist part U and the buttocks cover part C, in order to prevent contraction of the absorbent body 56 in the width direction WD in part or all of it, the width direction intermediate including a part or all of the part overlapping the absorbent body 56 in the width direction WD (preferably including the entire inner and outer joints 201, 202) is set as a non-stretchable area A1, and both sides in the width direction are stretchable areas A. 2 is preferable. Although it is preferable that the waist portion W is the stretchable region A2 over the entire width direction WD, a non-stretchable region A1 may be provided in the middle of the widthwise direction similarly to the lower waist portion U. A portion of the stretchable region A2 located in the front-rear direction LD range having the side seal portion 12A becomes a waist downward stretchable region A3.

In the stretchable region A2 and the non-stretchable region A1, the elastic members 15 to 17, 19 are supplied between the inner sheet layer 12H and the outer sheet layer 12S, and the elastic members 15, 16, 19 are fixed only to the portions located in the stretchable region A2 with a hot-melt adhesive. It can be constructed by cutting almost the whole into small pieces by pressurization and heating, leaving the stretchability in the stretchable region A2 and eliminating the stretchability in the non-stretchable region A1.

FIG. 19(a) shows a case where the elastic members 15, 16, and 19 are cut at one point in the middle in the width direction, and the elastic members 15 to 17, 17 and 17 are cut between the inner sheet layer 12H and the outer sheet layer 12S by means of a seal roll 170 having a cut protrusion 172 at one point in the circumferential direction on the outer peripheral surface, the cut protrusion 172 being heated to a desired temperature, and an anvil roll 180 having a smooth surface disposed opposite to the seal roll 170. The object to be cut to which 19 is attached is sandwiched so that the inner sheet layer 12H is on the seal roll side, and the elastic members 15, 16, and 19 are pressed and heated only at the portion sandwiched between the cutting convex portion 172 and the outer peripheral surface of the anvil roll 180 to cut. In a product subjected to such processing, as shown in FIG. 20(a), only the uncut remaining portion continuous from the elastic members 15, 16, 19 in the stretchable region A2 remains between the outer sheet layer 12S and the inner sheet layer 12H as the unnecessary elastic member 18, which is shrunk to its natural length.

FIG. 19(b) shows a case in which substantially the entire elastic members 15, 16, and 19 are finely cut, and the elastic members 15 to 17 and 19 are attached between the inner sheet layer 12H and the outer sheet layer 12S by means of a seal roll 170 having a pressing portion 171 having a large number of cutting protrusions 173 on the outer peripheral surface, the cutting protrusions 172 of which are heated to a desired temperature, and an anvil roll 180 having a smooth surface arranged opposite to the seal roll 170. are sandwiched so that the inner sheet layer 12H faces the seal roll side, and the elastic members 15, 16, and 19 are pressurized and heated only at the portions sandwiched between the cutting protrusion 173 and the outer peripheral surface of the anvil roll 180 to cut. In a product subjected to such processing, as shown in FIG. 20(b), the uncut portion continuous from the elastic members 15, 16, 19 of the stretchable region A2 and the cut piece of the elastic member discontinuous to the elastic members 15, 16, 19 of both stretchable regions A2 remain as the unnecessary elastic member 18 in a state of shrinking to its natural length alone between the outer sheet layer 12S and the inner sheet layer 12H.

As the sheet material for forming the inner sheet layer 12H and the outer sheet layer 12S, non-woven fabric is preferable although it can be used without particular limitation. When non-woven fabric is used, it is preferable that the basis weight per sheet is about 10 to 30 g/m ² .

The elastic members 15 to 19 are fixed to the exterior bodies 12F and 12B with hot-melt adhesive HM by various coating methods. The inner sheet layer 12H and the outer sheet layer 12S are preferably bonded with a hot-melt adhesive HM for fixing the elastic members 15-19 at the portions having the elastic members 15-19, respectively. In the portions of the exterior bodies 12F and 12B in the illustrated example having the elastic members 15 to 19, the hot melt adhesive HM is applied only to the outer peripheral surfaces of the elastic members 15 to 19 by an application means such as a comb gun or a sure wrap nozzle, and sandwiched between the sheet layers. The elastic members 15 to 19 may be fixed to both sheet layers only at both ends of the elastic region A2 in the elastic direction.

(High elongation area)
As shown in FIG. 13, at least the crotch-side end of the lower waist stretchable region A3 of the front body F forms a high stretch region A4 extending toward the center in the width direction from the rise gathers 60, and the rise portion 68 and the gather elastic member 63 preferably extend to the waist opening WO side into the high stretch region A4 of the front body F. As a result, the high stretch area A4 of the lower waist stretchable area A3 exists across the recess of the wearer's groin, so that the exterior bodies 12F and 12B can follow the expansion and contraction of the groove of the groin and firmly press the interior body 200. - 特許庁Furthermore, when the rising portion 68 of the rising gather 60 and the gathering elastic member 63 extend to the portion pressed by the high stretch region A4, the portion of the rising portion 68 having the gather elastic member 63 can rise so as to enter the recess of the groin on the basis of the high stretch region A4 firmly pressed against the groin. Therefore, in this pants-type disposable wearing article, the fit to the groin is remarkably improved.

In particular, in pants-type disposable diapers with a two-part exterior as shown in FIGS. 1 to 7, the fit around the legs is inevitably lowered, and the fit around the groin area is particularly likely to be lowered. That is, in a pants-type disposable diaper with an exterior divided into two parts, since the distance from the crotch part of the inner body 200 to the crossing position with the outer bodies 12F and 12B is long when worn, the inner body 200 is easily swung left and right about the crossing position, so that the inner body 200 is more likely to move in the lateral direction than the type provided with the integral outer body 12 that continues from the front body F to the back body B. Also, in the pants-type disposable diaper with the exterior divided into two, the crotch-side edges of the exterior bodies 12F and 12B are linear or nearly linear along the width direction WD, and intersect the side edges of the interior body 200 at a right angle or at an angle similar thereto. These mean that a pants-type disposable diaper with a two-piece exterior tends to have insufficient fit to the groin. Therefore, the above-described formation of the high elongation region A4 and the positional relationship between the high elongation region A4 and the riser gathers 60 are of great technical significance when applied to such a pants-type disposable diaper with a two-piece exterior. Furthermore, having the side flaps 70 and the side stretchable regions SG as in the illustrated example is preferable because the side stretchable regions SG elastically support the lateral movement of the interior body 200, and the side stretchable regions SG cover the sides of the interior body 200, so that gaps are less likely to occur on the sides of the interior body 200.

The positional relationship between the high-stretch region A4 and the rising gathers 60 can be determined as appropriate, but normally, the dimension of the non-stretchable region A1 in the front-back direction LD having the high-stretch region A4 is less than 1/2 (especially 1/3 to 1/2 times) of the dimension 56X in the width direction WD of the absorbent body 56. When it is 1/2 to 1 time (especially 2/3 to 3/4 times) the dimension 56X in the width direction WD, the positional relationship between the high stretch region A4 and the rising gathers 60 is appropriate, and the fit to the groin is particularly good, which is preferable.

The rising portion 68 of the rising gathers 60 and the gathering elastic member 63 preferably extend to the waist-side end of the high stretch region A4, but may extend only to the middle of the high stretch region A4 in the front-rear direction. In addition, the dimension in the front-rear direction LD of the overlapping portion of the high stretch region A4, the rising portion of the rising gathers 60, and the gathering elastic member 63 is preferably about 10 to 90%, particularly about 10 to 50%, of the dimension in the front-rear direction LD of the region where the inner body 200 and the front body F overlap.

The high stretch region may be provided over the entire front-rear direction of the lower waist stretch region as in the example shown in FIG.

For example, as shown in FIG. 17, the edges of the lower waist stretchable region A3 on the non-stretchable region A1 side extend stepwise or continuously toward the crotch side from the waist opening WO side so as to be positioned on the center side in the width direction WD, and the high stretch region A4 may be provided only on the crotch side of the lower waist stretchable region A3. Inguinal dimples are more pronounced on the crotch side and rarely occur on the waist side. Therefore, it is preferable to prevent shrinkage of the absorbent body 56 in other parts while improving the fit to the groin by providing the high elongation region A4 only in the part of the groin where the depression tends to be deep. In this case, the dimension in the longitudinal direction LD of the high stretch region A4 is preferably about 10 to 50%, particularly about 10 to 30%, of the dimension in the longitudinal direction LD of the region where the inner body 200 and the front body F overlap. Moreover, when the waist lower elastic member 19 incorporated in the high stretch area A4 is an elongated elastic member, the high stretch area A4 preferably includes a plurality of waist lower elastic members 19 . Furthermore, the edge of the non-stretchable area A1 side of the portion other than the high-stretchable area A4 in the lower waist stretchable area A3 preferably extends to the end of the absorbent body 56 in the width direction WD as shown in the figure, but may be positioned laterally from both side edges of the absorbent body 56. In the latter case, the edge of the non-stretchable region A1 side of the lower waist stretchable region A3 other than the high stretch region A4 may be positioned on the side flap 70 or laterally from the side edge of the side flap 70.

As can be seen from this example, the edge of the lower waist stretchable region A3 on the non-stretchable region A1 side, the edge of the highly stretchable region A4 on the non-stretchable region A1 side, and the edge of the region other than the highly stretchable region A4 on the non-stretchable region A1 side may be curved, stepped, or linear along the front-back direction LD.

14, 16 and 18, the lower waist elastic region A3 of the back body B can also be provided with a high stretch region A4 in order to maintain the stretch balance between the front and back. In this case, as can be seen from the combination examples shown in FIGS. 13 and 14, the combination examples shown in FIGS. 15 and 16, and the combination examples shown in FIGS. When the high stretch region A4 is provided in the lower waist stretch region A3 of the back body B, the rising portion 68 and the gathered elastic member 63 do not have to reach the high stretch region A4 of the back body B as shown in the figure, but they may reach the front body F in the same way. Also, although not shown, only the lower waist stretchable region A3 of the front body F may be provided with the high stretch region A4, and the lower waist stretchable region A3 of the back body B may not be provided with the high stretch region A4.

(internal and external joints)
Fixing of the inner body 200 to the outer bodies 12F and 12B can be performed by means of material welding such as heat sealing or ultrasonic sealing, or hot melt adhesive. In the illustrated example, the back surface of the inner body 200, that is, in this case, the back surface of the liquid-impermeable sheet 11 and the hot-melt adhesive applied to the root portion 65 of the rising gather 60 are interposed to fix to the inner surfaces of the outer bodies 12F and 12B. As shown in FIGS. 13 and 14, the inner and outer joints 201 and 202 for fixing the inner body 200 and the outer bodies 12F and 12B can be provided in substantially the entire region where the two overlap, for example, in a portion excluding both ends in the width direction of the inner body 200.

17 and 18, the inner and outer joints 201 and 202 are preferably provided only in the range from the end of one lower waist stretchable region A3 on the non-stretchable region A1 side to the end of the other lower waist stretchable region A3 on the non-stretchable region A1 side in the range in the front-back direction LD having the lower waist stretchable region A3. Restricting the width of the inner and outer joints 201 and 202 to the same extent as the width of the non-stretchable region A1 in this manner is preferable because unnecessary shrinkage of the absorbent body 56 can be suppressed. Here, if the widths of the inner and outer joints 201 and 202 are simply narrowed, the inner body 200 tends to move laterally, and the fit to the groin tends to deteriorate. However, in this underpants-type disposable diaper, the fit to the groin is excellent due to the formation of the above-described high stretch area A4 and the positional relationship between the high stretch area A4 and the rising gathers 60. Therefore, the conflicting effects of improving the fit to the groin and suppressing unnecessary shrinkage of the absorbent body 56 are compatible. In particular, having the aforementioned side stretchable regions SG is preferable because it can further compensate for a decrease in fit to the groin.

The inner and outer joints 201 and 202 may be located only in the non-stretchable region A1, but are preferably provided from the end of one lower waist stretchable region A3 on the non-stretchable region A1 side to the end of the other lower waist stretchable region A3 on the non-stretchable region A1 side. In the latter case, for example, as shown in the figure, if the edge of the lower waist stretchable area A3 on the side of the non-stretchable area A1 extends so as to be positioned toward the center in the width direction WD stepwise or continuously from the waist opening WO side toward the crotch side, the side edges of the inner and outer joints 201 and 202 similarly change in position in the width direction WD from the waist opening WO side toward the crotch side.

The width direction WD dimension of the inner and outer joints 201 and 202 can be determined as appropriate, but in normal cases, it can be about 90 to 120%, particularly about 100 to 110%, of the width direction WD dimension of the non-stretchable region A1.

As in the example shown in FIGS. 15 and 16, the inner and outer joints 201 and 202 can be shaped appropriately regardless of the position of the side edges of the lower waist stretchable region A3 on the non-stretchable region A1 side. Therefore, for example, like the front body F in the illustrated example, the inner and outer joint portions 201 and 202 can have a constricted shape in which the width of the intermediate portion is narrower than the width of both end portions in the front-rear direction LD. In this case, if the boundary between the rising part and the lodging part in the rising gather is positioned in the middle of the front-rear direction of the constricted part of the inner and outer joints in the unfolded state, the inner body and the outer body are not joined at the front-rear end position of the rising part. Also, like the back body B of the illustrated example, the inner and outer joints 201 and 202 may be formed in a T shape in which the width on the side of the crotch portion is narrower than the width on the side of the waist opening WO.

(Cover nonwoven fabric)
Since the inner body 200 is exposed between the front outer body 12F and the rear outer body 12B in the pants-type disposable diaper with the outer two parts divided, the back surface of the inner body 200 is preferably provided with a cover nonwoven fabric 13 extending from between the front outer body 12F and the inner body 200 to between the rear outer body 12B and the inner body 200 so that the liquid-impermeable sheet 11 is not exposed on the back side of the inner body 200. The inner surface and outer surface of the cover nonwoven fabric 13 can be adhered to the opposing surfaces via a hot-melt adhesive. The nonwoven fabric used for the cover nonwoven fabric 13 can be appropriately selected, for example, from materials similar to those of the exterior bodies 12F and 12B.

(non-woven fabric)
As the nonwoven fabric in the above description, a known nonwoven fabric can be appropriately used depending on the site and purpose. As the constituent fibers of the nonwoven fabric, for example, in addition to 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), regenerated fibers such as rayon and cupra, natural fibers such as cotton, etc., can be selected without particular limitation, and these can 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. The constituent fibers of the nonwoven fabric may be hydrophilic fibers (including those made hydrophilic by a hydrophilic agent), hydrophobic fibers or water-repellent fibers (including water-repellent fibers made water-repellent by a water-repellent agent). 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, needle punch nonwoven fabrics, point bonded nonwoven fabrics, laminated nonwoven fabrics (SMS nonwoven fabrics, SMMS nonwoven fabrics, etc. in which a meltblown layer is sandwiched between spunbond layers), etc., depending on the length of the fibers, the sheet forming method, the fiber bonding method, and the laminate structure, and any of these nonwoven fabrics can be used.

<Description of terms in the specification>
The following terms in the specification have the following meanings unless otherwise specified in the specification.

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

- The "front side" means the side closer to the wearer's skin when the pants-type disposable diaper is worn, and the "back side" means the side farther from the wearer's skin when the pants-type disposable diaper is worn.

・"Front surface" means the side of the member that is closer to the wearer's skin when the pants-type disposable diaper is worn, and the "back side" means the side that is farther from the wearer's skin when the pants-type disposable diaper is worn.

- "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.

- "Gel strength" is measured as follows. To 49.0 g of artificial urine (urea: 2 wt%, sodium chloride: 0.8 wt%, calcium chloride dihydrate: 0.03 wt%, magnesium sulfate heptahydrate: 0.08 wt%, and deionized water: 97.09 wt%), 1.0 g of superabsorbent polymer is added 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 (Curdmeter-MAX ME-500, manufactured by I. techno Engineering).

- "Matsuke" 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 measurement program) under the conditions of a load of 0.098 N/cm ² and a pressurized area of 2 cm ² .

・The amount of water absorption is measured according to JIS K7223-1996 "Testing method for water absorption of super absorbent polymer".

・The water absorption rate is defined as "time to end point" when JIS K7224-1996 "Testing method for water absorption rate of superabsorbent polymer" is performed using 2g of superabsorbent polymer and 50g of physiological saline.

- "Unfolded state" means a flat unfolded state without contraction or slack.

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

・If there is no description about environmental conditions for testing and measurement, the test and measurement shall be performed in a test room or equipment under standard conditions (test location: temperature 23±1°C, relative humidity 50±2%).

INDUSTRIAL APPLICABILITY The present invention can be applied to general pants-type disposable wearing articles such as shorts-type sanitary napkins, in addition to pants-type disposable diapers as described above.

REFERENCE SIGNS LIST 11 Liquid-impermeable sheet 12A Side seal portion 12B Rear exterior body 12E Waist extending portion 12F Front exterior body 12F, 12B Exterior body 12H Inner sheet layer 12S Outer sheet layer 13 Cover nonwoven fabric 15, 19 Waist lower elastic member 16 Cover elastic member 17 Waist elastic member 18 Unnecessary elastic member 200 Inner body 201, 20 2... Inner/outer joint part 30... Top sheet 40... Intermediate sheet 50... Absorbent element 56... Absorbent body 58... Wrapping sheet 60... Raising gather 60A... Tip side part 60B... Base side part 62... Gather sheet 63... Gather elastic member 67... Laying part 68... Raising part A1... Non-stretchable area A2... Stretchable area below waist A3... Lower waist stretchable area C... Buttock cover part L... Intermediate area , LD... front-back direction, SG... side stretchable area, T... waist area, U... lower waist part, W... waist part, WD... width direction, WO... waist opening, LO... leg opening, P1... first part, P2... second part, HM... hot melt adhesive, 70... side flap, 71... first sheet layer, 72... second sheet layer, 73... side elastic member, 74... innermost sheet layer, 75... outermost sheet layer, 76... inner sheet Layer 77... Non-joint part 79... Dedicated sheet material F... Front body A4... High elongation region B... Back body.

Claims (4)

An integrated exterior covering from the front body to the back body, or an exterior body provided separately for the front body and the back body;
an inner body including an absorbent attached to the outer body so as to extend from the front body to the back body;
a side seal portion in which both side portions of the exterior body of the front body and both side portions of the exterior body of the back body are respectively joined;
Equipped with a waist opening and a pair of left and right leg openings,
The exterior body has a non-stretchable region provided in the center in the width direction and a lower waist stretchable region divided into both sides in the width direction by the non-stretchable region in the front-back direction range including the side seal portion and the absorbent body.
The lower waist elastic region incorporates a lower waist elastic member, contracts in the width direction together with the lower waist elastic member, and is expandable in the width direction together with the lower waist elastic member,
Both sides of the inner body are provided with sit-up gathers,
The rising gathers have root portions attached to both sides of the inner body, a body portion extending from the root portions to both sides of the surface of the inner body, a lying portion formed by fixing the front and rear ends of the body portion to the surface of the interior body in a fallen state, a non-fixed rising portion positioned between the front and rear lying portions, and a gathered elastic member provided along at least a tip portion of the rising portion along the front-rear direction,
The main body portion includes a root side portion extending to the center in the width direction and a tip side portion extending outward in the width direction by folding back the tip of the root side portion,
The rising portion contracts in the front-rear direction together with the gathering elastic member to rise from the surface of the inner body, and is extensible in the front-rear direction together with the gathering elastic member.
In pants-type disposable articles of wear;
The edge of the non-stretchable region side of the lower waist stretchable region of the front body extends stepwise or continuously from the waist opening side toward the crotch side so as to be positioned at the center side in the width direction,
The lower waist stretchable region of the front body is provided on the crotch side and extends to the center in the width direction from the rise gathers, and the high stretch region is adjacent to the waist opening side and is made up of a region that does not extend to the center side in the width direction from the rise gathers.
The widthwise dimension of the non-stretchable region in the front-back direction range having the high stretching region is less than 1/2 of the widthwise dimension of the absorbent body,
A boundary between the highly stretched region and other regions in the lower waist elastic region of the front body is arranged at a position overlapping the center of the lodged portion in the front-rear direction,
The rising portion and the gathered elastic member extend to the waist opening side to the high stretch region of the front body,
前記前身頃における前記ウエスト下方伸縮領域を有する前後方向範囲にわたり、前記内装体と前記外装体とを接合する内外接合部の幅方向の寸法が前記非伸縮領域の幅方向の寸法の１２０％以下となるように、前記内外接合部の側縁が前記ウエスト開口側から股間側に向かうにつれて段階的又は連続的に幅方向の中央側に位置するように延びており、それによって前記内外接合部は、前記ウエスト下方伸縮領域を有する前後方向範囲では、一方のウエスト下方伸縮領域の前記非伸縮領域側の端部から、他方のウエスト下方伸縮領域の前記非伸縮領域側の端部までの範囲にしか設けられていない、
A pants-type disposable wearing article characterized by: The interval between the rising gathers on both sides is 1/2 to 1 times the dimension in the width direction of the absorbent body.
The pants-type disposable wearing article according to claim 1. The outer body is separately provided on the front body and the back body,
The exterior body of the front body and the exterior body of the back body are spaced apart in the front-rear direction on the crotch side,
The inner body extends in the front-rear direction from the outer body of the front body to the outer body of the back body, and is joined to the outer body of the front body and the outer body of the back body respectively,
The side seal portions are portions where both side portions of the outer body of the front body and both side portions of the outer body of the back body are joined, respectively.
The pants-type disposable wearing article according to claim 1 or 2 . On both sides of the inner body, side flaps extending laterally from the rising gathers extend in the front-rear direction from the outer body of the front body to the outer body of the back body,
The side flap has a side elastic region that elastically expands and contracts in the front-rear direction,
The side stretchable region incorporates a side elastic member, contracts in the front-rear direction together with the side elastic member, and is expandable in the front-rear direction together with the side elastic member,
The side elastic regions extend to the waist opening side to the high stretch region of the front body,
The pants-type disposable wearing article according to claim 3 .

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