TW202300126A - absorbent article - Google Patents

Abstract

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

Description

absorbent article

The present invention relates to an absorbent article with improved followability of erected wrinkles.

At present, most absorbent articles such as disposable diapers and sanitary napkins have erected folds (also called three-dimensional folds) erected from both sides of the top sheet surface in the width direction. By having the vertical pleats, the lateral movement of excrement is blocked by the vertical pleats, thereby preventing so-called horizontal leakage.

Most of the erected pleats have: a root portion installed on the outside in the width direction of an imaginary line passing through the blocking positions on both sides of the top sheet surface in the width direction and continuous in the front-rear direction; a body portion extending from the root portion The inner edge of the width direction extends; the fixing part is fixed to the top sheet surface in a lying state at the front end and the rear end of the body part; and the middle part is located between the front and rear fixing parts in the body part , and is not fixed to the top sheet surface. These portions are formed of a wrinkled sheet such as nonwoven fabric. Among them, at least at the top end of the vertical pleats, the pleated sheet is folded back at the top (protruding end) to form a double-layer structure, and between the layers of at least the top end of the middle part, an elongated shape is installed along the front-back direction in an elongated state. The gathered elastic member (for example, refer to Patent Document 1 and Patent Document 2).

The middle portion is contracted together with the gather elastic member by the contraction force of the gather elastic member, and can be extended together with the gather elastic member. In the wearing state, the front-to-rear dimension of the top end of the middle part becomes shorter due to the contraction force of the gathered elastic member, and the middle part is not fixed to the top sheet, whereby the middle part is closer to the top end (farthest from the root side) The position) becomes higher, and the closer to the fixed part of the front end and the rear end, the lower it becomes.

In addition, in some absorbent articles such as tape type disposable diapers, the main body portion of the upright gathers is often extended inward in the width direction without being folded back from the base, and the top end of the main body portion is directed inward in the width direction.

However, such inward-type erected gathers have the following problems: there is a limit to the erected angle (or erected height) in the crotch portion; It has excellent leakage resistance against soft stools, but it is difficult to follow the movement of the legs and move to the outside when lying on the side, and the tip is easy to closely contact the skin.

[Prior Art Literature] (patent documents) (Patent Document 1) Japanese Patent Laid-Open No. 2019-130278 (Patent Document 2) Japanese Patent Laid-Open No. 2018-140068

(Problem to be solved by the invention) Therefore, the main subject of the present invention is to improve the erection angle of the inward erected folds.

(means to solve problems) Absorbent articles that solve the above-mentioned problems are as follows. ＜The first form＞ An absorbent article characterized by having: absorber; a liquid-permeable top sheet disposed on the surface side of the absorbent body; and Standing pleats are respectively arranged on both sides of the width direction of the surface of the aforementioned top sheet; The above-mentioned standing pleats have: a root part installed on the outside of the width direction of an imaginary line, and the above-mentioned imaginary line passes through the blocking positions on both sides of the width direction of the surface of the top sheet and is continuous in the front-rear direction; The inner edge of the aforementioned root in the width direction is folded back and extends toward the inner side of the width direction; The aforementioned body portion has: a front end portion and a rear end portion, having a fixing portion fixed to the aforementioned top sheet; and a middle portion, located between the front end portion and the rear end portion, and not fixed to the aforementioned top sheet; On at least the top end of the middle part, a slender elastic member with folds along the front-rear direction is installed, The middle portion is contracted together with the gather elastic member by the contraction force of the gather elastic member, and can be extended together with the gather elastic member, At least one of the front end portion and the rear end portion on the inner side in the width direction is provided with a free portion that is not fixed to the top sheet continuously from the middle portion, and the front end portion and the rear end portion The above-mentioned free part of the end part becomes the fixed part, The width of the aforementioned free portion is 1/6-1/3 of the width of the aforementioned middle portion, and the dimension of the aforementioned free portion in the front-rear direction is 1-9.5 times of the width of the aforementioned free portion.

(Effect) In the previous inwardly erected pleats, the fixing parts at the front and back of the main body are provided across almost the entire width direction of the main body. At this time, in the wearing state, the front and rear fixed parts suppress the erection of the middle part across the entire width direction, so the erection angle of the middle part is reliably limited, and the top end of the middle part is also prevented from tilting outward. In addition, the middle part is not easy to follow the movement of the legs and move outward, and the top of the middle part is easy to closely contact the skin. On the other hand, in this absorbent article, a free portion having a certain width is provided continuously from the middle portion at the end portion on the inner side in the width direction of at least one of the front end portion and the rear end portion of the main body portion. (the part that is not fixed to the top sheet). Therefore, although the front and rear fixing parts suppress the erection of the middle part in the wearing state, the degree of suppression is determined by the erection of the free part (in a continuous manner with the middle part, but because the width of the free part is short, it does not Not erected like the middle part) and relaxed, so the erection angle of the middle part will be definitely greater than the situation without the free part. In addition, due to the existence of the free part, the tip of the middle part is easy to fall to the outside, and the middle part is easy to move to the outside following the movement of the legs. Furthermore, as a result, the top end of the middle portion is less likely to come into close contact with the skin.

＜The second aspect＞ The absorbent article according to the first aspect, wherein the width of the free portion is 3.5 mm or more, The intermediate portion has the gather elastic member in a front end region having a width equal to that of the free portion, and does not have the gather elastic member outside the front end region.

(Effect) The width of the free portion can be appropriately specified, but is preferably 3.5 mm or more. In addition, it is preferable that the middle part has the gathered elastic member only in the front end region where the width is equal to the width of the free part, and the part with the gathered elastic member is less likely to come into close contact with the skin. The gathered elastic member may extend to the free part, and may be fixed in this case, or may be unfixed so that no contraction force acts on it.

＜The third aspect＞ The absorbent article according to the first aspect or the second aspect, wherein in the region overlapping the backside of the middle part in the unfolded state, in the root side region equal to the width of the fixing part, the ratio of the top sheet is larger than that of the top sheet The back side of the material has an elongated inner elastic member along the front-to-back direction, The root side region can be contracted together with the inner elastic member by the contraction force of the inner elastic member, and can be extended together with the inner elastic member.

(Effect) By providing the inner elastic member at the position of this aspect, the part having the inner elastic member rises, and the part serving as the base of the raised pleats is inclined so that the rising angle of the middle part becomes large, so it is preferable.

＜Fourth aspect＞ The absorbent article according to the third aspect, wherein the absorbent body has a narrower portion in the middle of the front-to-back direction than its front and back sides, The aforementioned inner elastic member is arranged to pass through the narrowed portion.

(Effect) Since the narrowed portion is a portion without an absorber, its rigidity is lower than that of a portion with an absorber and is easily deformed. Therefore, if the inner elastic member is provided so as to pass through this position, the portion that becomes the base of the raised gathers will be more likely to incline, which is preferable.

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

(Effect) Since the movable range of the legs is greater at the front than at the rear, it is a preferred embodiment to make the width of the free portion at the front end of the main body wider than the width of the free portion at the rear end as in this aspect.

＜Sixth aspect＞ The absorbent article according to any one of the first to fifth aspects, which is a disposable diaper for low birth weight infants.

(Effect) For disposable diapers for low birth weight infants, a weak but soft fit is preferable to a firm fit. Therefore, the raised gathers having the above-mentioned free portions are suitable for use in disposable diapers for low birth weight infants.

(Effect of Invention) According to the present invention, there are also advantages such as suppression of exudation of excrement fluid at the root of the vertical folds.

Figures 1 to 6 show a connection-type disposable diaper (generally called a strip-type disposable diaper) as an example of an absorbent article, and the symbol X in the figure represents the full width of the diaper except for the connection belt 13 , the symbol L represents the full length of the diaper. In addition, unless otherwise indicated, the dot pattern portion and * mark in the cross-sectional view indicate hot-melt adhesive as a joining means for joining the constituent members located on the front side and the back side. Hot melt adhesive can be applied by slit coating, continuous linear or dotted droplet coating, spiral, Z-shaped, wavy, etc. spray coating, or pattern coating (hot melt adhesive using letterpress method) Transfer printing) and other known methods of coating. Alternatively or in combination therewith, in the fixing portion of the elastic member, hot melt adhesive is applied to the outer peripheral surface of the elastic member to fix the elastic member to the adjacent member. As the hot melt adhesive, there are, for example, EVA (Ethylene-Vinyl Acetate; ethylene-vinyl acetate)-based, adhesive rubber-based (elastic system), olefin-based, polyester-polyamide-based, and the like, and can be used without particular limitation. As the fixing or joining means for joining the constituent members, means using material fusion, such as heat sealing or ultrasonic sealing, can be used. In the portion where liquid permeability in the thickness direction is required, constituent members adjacent in the thickness direction are fixed or bonded in an intermittent pattern. For example, in the case of such intermittent fixing or bonding by hot melt adhesive, intermittent pattern coating in a spiral, Z-shape, wave, etc. In the case of a range of more than the width, intermittent pattern coating in a spiral, Z-shape, wave shape, etc. may be performed with or without gaps in the width direction.

This connected disposable diaper has: a span part M including the center of the front-rear direction LD, a ventral part F extending to the front side of the center of the front-rear direction LD, and a back extending to the rear side of the center of the front-rear direction LD. Side part B. In addition, this connected disposable diaper has: the absorber 56 built in the range including the crotch M, the liquid-permeable top sheet 30 covering the front side of the absorber 56, and the liquid-proof top sheet 30 covering the back side of the absorber 56. The permeable sheet 11, and the exterior nonwoven fabric 12 covering the back side of the liquid-impermeable sheet 11 and constituting the outer surface of the product. The crotch part M refers to the range in the front-rear direction LD including the narrowed portion 56n when the absorbent body 56 has the narrowed portion 56n described later, and means the range in the front-rear direction LD including the narrowed portion 56n when the absorbent body 56 does not have the narrowed portion 56n. The part located in the center of the LD in the front-back direction and whose size in the front-back direction is 30% to 60% of the total length of the product.

In the following, the materials and characteristics of each part will be described in sequence. In addition, as a nonwoven fabric in the following description, a well-known nonwoven fabric can be used suitably according to a site or purpose. As the constituent fibers of the nonwoven fabric, for example, synthetic fibers such as olefins such as polyethylene or polypropylene, polyesters, polyamides, etc. Regenerated fibers such as rayon and copper amine fibers, natural fibers such as cotton, etc. may be selected in a limited manner, and these may be mixed and used. In order to improve the softness of the nonwoven fabric, it is preferable to make the constituent fibers into crimped fibers. In addition, the constituent fibers of the nonwoven fabric can be hydrophilic fibers (including fibers made hydrophilic by a hydrophilizing agent), hydrophobic fibers or water-repellent fibers (including fibers made water-repellent by a water-repellent agent) . In addition, non-woven fabrics are usually classified into short-fiber non-woven fabrics, long-fiber non-woven fabrics, spunbond non-woven fabrics, melt-blown non-woven fabrics, spunlace non-woven fabrics, heat-bonded (hot air) non-woven fabrics, Needle-punched non-woven fabrics, point-bonded non-woven fabrics, laminated non-woven fabrics (including SMS non-woven fabrics with a meltblown layer sandwiched between spunbond layers, SMMS non-woven fabrics, etc.), and any of these non-woven fabrics can also be used. (Absorbent Body) The absorbent body 56 is a part that absorbs excrement and holds it, and may be formed of an aggregate of fibers. As the fiber aggregate, in addition to aggregates obtained by piling up short fibers such as cotton pulp or synthetic fibers, those obtained by opening tows (fiber bundles) of synthetic fibers such as cellulose acetate can also be used. Filament aggregates. As the basis weight of the fiber, it can be made, for example, about 100 g/m ² to 300 g/m ² in the case of piling up cotton-like pulp or short fibers, and it can be made, for example, in the range of 30 g/m 2 to 30 g/m ² in the case of filament aggregates. About 120g/ ^m2 . In the case of synthetic fibers, the fineness is, for example, 1dtex to 16dtex, preferably 1dtex to 10dtex, more preferably 1dtex to 5dtex. In the case of an aggregate of filaments, the filaments may be non-crimped fibers, but crimped fibers are preferred. The degree of crimping of the crimped fibers can be, for example, 5 to 75 per 2.54 cm, preferably 10 to 50, and more preferably about 15 to 50. Alternatively, crimped fibers that are uniformly crimped may be used.

The shape of the absorber 56 can be appropriately specified. For example, the absorber 56 may be formed in an appropriate shape such as a rectangular shape, in addition to being formed in an approximately hourglass shape in which the portion located at the crotch M has narrower portions 56n narrower than the front and rear sides as shown in the figure. Normally, the absorber 56 is preferably provided from the front side to the rear side of the crotch part, but it is not limited thereto.

(superabsorbent polymer particles) In the absorber 56, superabsorbent polymer particles may be contained in a part or the whole thereof. The term "superabsorbent polymer particles" includes "powder" in addition to "particles". As the superabsorbent polymer particles, those used in such absorbent articles can be used as they are. The particle size of the superabsorbent polymer particles is not particularly limited. For example, it is desirable to sieve (vibrate for 5 minutes) using a 500 μm standard sieve (JIS Z8801-1: 2006), and evaluate the When the particles falling under the sieve are sieved (vibrating for 5 minutes) using a 180 μm standard sieve (JIS Z8801-1:2006), the ratio of the particles remaining on the 500 μm standard sieve is 30% by weight or less, and the remaining The ratio of particles on a standard sieve of 180 μm is 60% by weight or more.

The material of the superabsorbent polymer particles can be used without particular limitation, but it is preferable that the water absorption amount is 40 g/g or more. As superabsorbent polymer particles, there are starch-based, cellulose-based, or synthetic polymer-based particles, and starch-acrylic acid (salt) graft copolymer, saponified product of starch-acrylonitrile copolymer, and carboxymethyl cellulose can be used. Sodium cross-linked product or acrylic acid (salt) polymer, etc. As the shape of the superabsorbent polymer particles, it is preferable to use a generally used powder or granular shape, but other shapes may also be used.

As the superabsorbent polymer particles, those having a water absorption rate of 70 seconds or less, especially 40 seconds or less, can be suitably used. If the water absorption speed is too slow, so-called rewet in which the liquid supplied in the absorber 56 returns to the outside of the absorber 56 is likely to occur.

In addition, as the superabsorbent polymer particles, those having a gel strength of 1000 Pa or more can be suitably used. Thereby, even when the absorber 56 is made fluffy, stickiness after liquid absorption can be effectively suppressed.

The basis weight of the superabsorbent polymer particles can be appropriately determined according to the absorption capacity required for the application of the absorbent body 56 . Therefore, it cannot be generalized, but it can be made into 50g/m ² ~350g/m ² under normal circumstances.

(Packaging Sheet) The absorbent body 56 may be incorporated as the absorbent element 50 wrapped by the packaging sheet 58 in order to prevent superabsorbent polymer particles from protruding or to improve the shape retention of the absorbent body 56 . As the packaging sheet 58, toilet paper, especially crepe paper, non-woven fabric, polyethylene-laminated non-woven fabric, a sheet with small holes, etc. can be used. However, a sheet in which superabsorbent polymer particles do not protrude is more desirable. When using non-woven fabric instead of crepe paper, it is especially suitable to use hydrophilic SMMS (spunbond/meltblown/meltblown/spunbond) nonwoven fabric, and its material can be polypropylene, polyethylene/polypropylene, etc. The fiber basis weight is preferably 5g/m ² -40g/m ² , especially 10g/m ² -30g/m ² .

The wrapping sheet 58 may wrap the whole absorber 56 with one sheet as shown in FIG. 3 , or wrap the whole absorber 56 with a plurality of sheets such as upper and lower sheets. The packaging sheet 58 can also be omitted.

(top sheet) The top sheet 30 is liquid-permeable, for example, a non-woven fabric with or without holes, or a plastic sheet with holes, etc. can be used.

The top sheet 30 extends from the front end to the rear end of the product in the front-rear direction, and can be properly deformed as needed. In addition, the top sheet 30 of the illustrated example extends to the outside of the boundary between the main body portion 66 and the root portion 65 of the rising gathers 60 described later in the width direction WD, but the present invention is not limited thereto. The top sheet 30 in the illustrated example extends laterally beyond the side edges of the absorber 56 , but it can be properly deformed if necessary, such as making the side edges of the top sheet 30 more inside than the side edges of the absorber 56 .

(intermediate sheet) Although not shown, an intermediate sheet (also referred to as a "second sheet") may be adjacently provided on the back side of the top sheet 30 in order to prevent back seepage of the liquid passing through the top sheet 30 .

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

The intermediate sheet may be arranged in the center shorter than the width of the absorber 56 , or may be arranged so as to cover the entire width of the absorber 56 . In addition, the middle sheet may be provided over the entire length of the diaper, or may be provided only in the middle part including the excretion position.

(Liquid-impermeable sheet) The liquid-impermeable sheet 11 is not particularly limited, but preferably has moisture permeability. As the liquid-impermeable sheet 11, for example, a microporous material obtained by kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene, forming a sheet, and stretching in a uniaxial or biaxial direction can be suitably used. Sheet. In addition, as the liquid-impermeable sheet 11, a nonwoven fabric-based sheet having improved water repellency can also be used.

The liquid-impermeable sheet 11 preferably has a protruding portion protruding outward in the width direction WD from the top sheet 30 . The liquid-impermeable sheet 11 preferably extends over the same range as the absorber 56 or a wider range in the front-rear direction LD and the width direction WD.

(Exterior Nonwoven Fabric) The exterior nonwoven fabric 12 covers the entire back side of the liquid-impermeable sheet 11 to make the outer surface of the product look like cloth. In addition to using one piece of nonwoven fabric, it is also possible to use a plurality of sheets stacked. In the latter case, it is preferable to bond the non-woven fabrics to each other with hot melt adhesive or the like. In the case of using a non-woven fabric, it is preferably a non-woven fabric whose constituent fibers have a fineness of 1.0dtex to 6.0dtex, a basis weight of 15g/m ² to 45g/m ² and a thickness of 0.5mm to 3.0mm.

Instead of the exterior nonwoven fabric 12, a sheet other than a nonwoven fabric may be used, and the exterior nonwoven fabric 12 may also be omitted.

(end wings, side wings) The connected type disposable diaper of the illustrated example has: a pair of end flaps EF extending to the front and rear sides of the absorber 56, respectively, without the absorber 56; and a pair of side flaps SF extending respectively to the The two side edges of the absorber 56 are closer to the side, and there is no absorber 56 . The side flaps SF may be formed from a partially continuous material (exterior nonwoven fabric 12, etc.) having the absorber 56 as shown in the figure, or may be formed by attaching other materials.

(wing part) In this connection type disposable diaper, the back side part B has the wing part WP which protrudes outside the width direction WD rather than the crotch part M. As shown in FIG. Similarly, the abdominal part F also has the wing part WP which protrudes outside the width direction WD rather than the crotch part M. As shown in FIG. These wing parts WP may be formed with members different from other parts. However, in the structure having the side wing portion SF as shown in the figure, if the middle of the side portion of the side wing portion SF in the front-rear direction LD is cut off to form a structure from the side edge of the crotch portion M to under the wing portion WP The narrowed side edge 70 up to the edge 71 is preferable because the fin portion WP is formed as a result, since it is easy to manufacture.

(link belt) As shown in FIG. 1, FIG. 2 and FIG. 6, the wing portion WP of the back portion B is respectively provided with a connection belt 13 detachably connected to the outer surface of the ventral portion F. When wearing the diaper 10, the connecting belt 13 is wound around the outer surface of the abdominal part F from both sides of the waist, and the connecting part 13A of the connecting belt 13 is connected to an appropriate position on the outer surface of the abdominal part F.

As shown in FIG. 6, the connection belt 13 has: a sheet base material, forming a base end portion 13C fixed to the wing portion WP and a body portion 13B protruding from the base end portion 13C; The connecting portion 13A is provided in the middle portion of the main body portion 13B in the width direction WD of the sheet base material. In the main body portion 13B, the side closer to the base end portion 13C than the connection portion 13A is a non-connection portion that is not connected to the abdominal portion F. As shown in FIG. The side edge of the base end portion 13C may coincide with the side edge of the wing portion WP, or may be slightly away from the side edge of the wing portion WP inwardly in the width direction WD as shown in the figure. The inner edge in the width direction of the connecting portion 13A may coincide with the side edge of the wing portion WP, but it is preferably sufficiently separated from the side edge of the wing portion WP outward in the width direction WD as shown in FIG. 6 .

As the connecting portion 13A, an adhesive layer may be provided in addition to the bristle material (hook material) of the mechanical fastening tape (surface fastening tape). The bristle material has many fastening protrusions on its connecting surface. As the shape of the fastening protrusions, there are (A) "レ"-shaped, (B) J-shaped, (C) mushroom-shaped, (D) T-shaped Arbitrary shapes, such as (E) double J-shape (combined back-to-back J-shape), etc. may be used.

In addition, non-woven fabrics, plastic films, polyethylene laminated non-woven fabrics, paper or composite materials can be used as the sheet material forming the base end portion 13C to the main body portion 13B. 60g/m ² ~100g/m ² , spun-bonded non-woven fabric, air-through non-woven fabric or spunlace non-woven fabric with a thickness of less than 1mm.

The connection belt 13 may expand and contract in the width direction WD at least a part of the non-connecting part, or may not expand and contract as a whole.

(Target Department) A target portion 12T is provided at a connection portion of the connection belt 13 in the ventral portion F. As shown in FIG. The target portion 12T can be provided by attaching a sheet material for facilitating connection to the outer surface of the ventral portion F as shown in the figure.

The sheet-like material used to form the target portion 12T is not particularly limited. When the connecting portion 13A is a bristle material, for example, a long-fiber nonwoven fabric in which the fibers are partially fused to each other by ultrasonic welding in intermittent patterns can be used. .

In addition, when the connecting portion 13A is a bristle material, as the sheet material for forming the target portion 12T, a composite sheet material can be used, and the composite sheet material is made of a plastic film or a non-woven fabric. The surface of the material is sewn with a plurality of loops of thread that wrap around the bristle material like buckle protrusions.

Furthermore, when the connection part 13A is a bristle material, and the connection part of the connection belt 13 in the abdominal part F is made of a non-woven fabric (such as the case where the exterior non-woven fabric 12 is generally shown in the illustration), it is not necessary to form a label. For the target portion 12T, a sheet material is added, but an appropriate portion of the exterior non-woven fabric 12 is made into the target portion 12T, and the bristle material is wound around the fibers of the exterior non-woven fabric 12 to be connected.

On the other hand, in the case where the connecting portion 13A is an adhesive material layer, as the sheet material for forming the target portion 12T, a sheet material composed of a plastic film with a smooth surface such as high adhesiveness can be used. Materials whose surface has been peeled off.

(pulls up) In order to block the excrement that spreads and moves laterally on the top sheet 30 and prevent so-called horizontal leakage, vertical folds 60 are respectively provided on both sides of the width direction WD of the surface of the top sheet 30 .

The erected gathers 60 have: a root portion 65 installed outside the width direction WD of an imaginary line 60B passing through blocking positions on both sides of the width direction WD of the surface of the top sheet 30 and continuous in the front-rear direction LD and the main body portion 66 extends inwardly in the width direction WD without turning back from the inner edge of the root portion 65 in the width direction WD. In addition, the main body portion 66 has: a front end portion 67 and a rear end portion 69, and has a fixed portion BP fixed to the top sheet 30 (in other words, the range in the front and rear direction LD with the fixed portion BP in the main body portion 66 is the front end portion 67 and the rear end portion 67). end 69); and the middle part 68, which is located between the front end 67 and the rear end 69, and is not fixed to the top sheet 30; at least the top end of the middle part 68 is installed along the front-back direction LD. The pleated elastic member 63 is elongated.

The body portion 66 and the root portion 65 can be formed by a corrugated sheet 62 made of an inner layer 62n by folding in half at the top end of the body portion 66 (the end portion on the side opposite to the root portion 65 side). And the two-layer structure of the outer layer 62f. In this case, the gathered elastic member 63 may be provided between the inner layer 62n and the outer layer 62f. The inner layer 62n may extend to the root portion 65 as shown in FIG. 3 , and may extend only to the middle position of the main body portion 66 in the width direction WD, although not shown. That is, one layer may be provided on the root portion 65 side of the main body portion 66 . In addition, the creased sheet 62 may have a layer structure of three or more layers, and in particular may have a liquid-impermeable film as an intermediate layer. When the creased sheet 62 is made into a multi-layer structure, one piece of nonwoven fabric may not be folded back, or the number of layers may be increased by folding one piece of nonwoven fabric back and attaching other nonwoven fabrics to increase the number of layers.

The root portion 65 has a joint opening in the width direction WD on the side of the top sheet 30 that passes through the blocking position and is continuous in the front-rear direction LD. In addition, the root portion 65 in the illustrated example has a protruding portion protruding outward in the width direction WD from the top sheet 30, and the protruding portion is bonded to the inner surface of each side wing portion SF by hot-melt adhesive or the like. It is the side part of the liquid-impermeable sheet 11 in the illustrated example and the side part of the exterior nonwoven fabric 12 positioned outside the width direction WD.

At both ends of the front-rear direction LD in the main body portion 66, there are fixed portions BP fixed on the surface of the top sheet 30, but the middle portion 68 between the front and rear fixed portions BP is not fixed on the surface of the top sheet 30. part of. The middle portion 68 is contracted together with the gathers elastic member 63 by the contraction force of the gathers elastic member 63 and can be extended together with the gathers elastic member 63 . As a result, in the wearing state, the dimension in the front-rear direction LD of the top end of the middle part 68 is shortened due to the shrinkage force of the gathered elastic member 63, and the middle part 68 is not fixed to the top sheet 30, but as in the first As shown in Fig. 7 and Fig. 9, the middle part 68 is higher as it gets closer to the tip (the farthest part from the root part 65 side), and the closer to the fixed part BP of the front end part 67 and the rear end part 69, the lower it is. put up.

The type of the gather sheet 62 is not particularly limited, and in general, a water-repellent nonwoven fabric is used from the viewpoint of skin feel and liquid barrier properties. Especially in terms of both skin feel and liquid barrier properties, non-woven fabrics (SMS non-woven fabrics, SMMS non-woven fabrics, SSMS non-woven fabrics, SSMMS non-woven fabrics) with meltblown layers between spunbond layers are more suitable. In addition to using one piece of nonwoven fabric, it is also possible to use a plurality of sheets stacked. In the latter case, it is preferable to bond the non-woven fabrics to each other with hot melt adhesive or the like.

As the gather elastic member 63, an elastic member such as filament-shaped, string-shaped, belt-shaped, elongated rubber or the like can be used. The gather elastic members 63 may be provided in plural on each side, in addition to only one being provided on each side as shown in the figure. The elongation of the pleated elastic member 63 in the unfolded state can be appropriately specified, preferably about 150% to 250%, more preferably 180% to 230%. When synthetic sericin such as spandex is used as the wrinkled elastic member 63 , the thickness thereof is preferably 300 dtex to 700 dtex, more preferably 400 dtex to 500 dtex.

Characteristically, a free portion that is not fixed to the top sheet 30 is provided in a continuous manner from the aforementioned intermediate portion 68 at the inner end portion of the front end portion 67 and the rear end portion 69 of the main body portion 66 in the width direction WD. FP, and the body portion 66 other than the free portion FP becomes the fixed portion BP. In addition, the width x1 of the free part FP is 1/6~1/3 of the width x2 of the middle part 68, and the dimension of the free part FP in the front-back direction LD is 1~9.5 times of the width x1 of the free part FP. Furthermore, the width x1 of the free portion FP is constant in the illustrated example, but it can also be changed depending on the position in the front-back direction LD, and in this case, it means the minimum value. The width x2 of the middle portion 68 is constant in the illustrated example, but it can also be changed depending on the position in the front-back direction LD, and in this case, it means the maximum value.

For this kind of inward erected folds 60, as shown in Fig. 7 and Fig. 9, although the front and rear fixing parts BP restrain the erection of the middle part 68 in the wearing state, the degree of restraint is controlled by freedom. The erection of the part FP (in a continuous manner with the middle part 68, but because the width x1 of the free part FP is relatively short, it is not erected like the middle part 68) is relaxed, so the erection angle of the middle part 68 Compared with the case where there is no free portion FP, it is definitely increased. In addition, due to the presence of the free portion FP, as shown in FIG. 8 , the tip of the intermediate portion 68 can easily fall outward, and the intermediate portion 68 can easily move outward following the movement of the legs. Furthermore, as a result, the top end of the middle portion 68 is less likely to be in close contact with the skin.

The size of the free portion FP can be appropriately specified within the above range. The width x1 of the free portion FP is preferably 2/11˜1/4 of the width x2 of the middle portion 68 . More specifically, the lower limit of the width x1 of the free portion FP is preferably 3.5 mm. In addition, when both the front end portion 67 and the rear end portion 69 have the free portion FP, the width x1 of the free portion FP of the front end portion 67 and the width x1 of the free portion FP of the rear end portion 69 can also be equal, but because the legs The movable range is that the front side is larger than the rear side, so as shown in FIG. Making 1.2 times ~ 1.5 times) is a better form.

The dimension y1 of the free portion FP in the front-rear direction LD is more preferably 2 to 8.5 times the width x1 of the free portion FP. The free part FP is preferably as shown in the first figure, when it is provided at the front end 67 of the main body 66, it is provided across the entire length of the front end 67, and when it is provided at the rear end 69 of the main body 66 In some cases, it is provided across the entire length of the rear end portion 69 . However, when the free portion FP is provided on the front end portion 67, as shown in FIG. 11, the free portion FP may be provided only on the rear side of the front end portion 67, and the front side of the front end portion 67 may be formed as a whole across the width direction WD. Fixed part BP. Similarly, when the free portion FP is set on the rear end portion 69, as shown in FIG. 11, the free portion FP is only provided on the front side of the rear end portion 69, and the rear end portion 69 is set across the width of the rear end portion 69. The direction WD as a whole makes the fixing portion BP. It can be seen that, when the free portion FP is arranged on both the front end portion 67 and the rear end portion 69 of the main body portion 66, the size of the free portion FP of the front end portion 67 in the front-rear direction LD is the same as that of the free portion of the rear end portion 69. The dimensions of LD in the front and rear directions of FP may be equal or different. The free portion FP is preferably provided on both the front end portion 67 and the rear end portion 69 of the main body portion 66 as shown in the figure, but may also be provided only on the front end portion 67 or only on the rear end portion 69 .

The gather elastic member 63 may also be provided other than the top end of the intermediate portion 68 as shown in the illustration, but as shown in the illustration, it is only provided in the top end side region whose width is equal to the width x1 of the free portion FP, and in this It is preferable not to have the gathered elastic member 63 other than the tip side region, since the part with the gathered elastic member 63 is less likely to come into close contact with the skin.

In addition, the gather elastic member 63 may extend to the free part FP, and may not extend to the free part FP. In the case of the former, the part of the pleated elastic member 63 located at the free portion FP can be fixed to the free portion FP so that the shrinkage force of the pleated elastic member 63 can act on the free portion FP, or the part of the pleated elastic member 63 located at the free part FP can not be fixed. Part of the portion FP is fixed to the free portion FP, and the shrinkage force of the gather elastic member 63 does not act on the free portion FP.

(medial plane fold) As shown in the figure, it is preferable that in the region overlapping the back side of the middle part 68 in the unfolded state, in the root side region equal to the width x3 of the fixed part BP, the back side of the top sheet 30 is preferably provided. In the elongated inner elastic member 61 along the front-rear direction LD, the root side region is contracted together with the inner elastic member 61 by the contraction force of the inner elastic member 61, and can be elongated together with the inner elastic member 61 (to become a so-called flat surface). folds). By arranging such an inner elastic member 61, the part having the inner elastic member 61 can be bulged in the direction shown by the hollow arrow in FIGS. The part of the base of the erected folds 60 is inclined (this state is not shown in Figs. 7 and 8). The inner elastic member 61 may also be omitted.

The position of the inner elastic member 61 can be appropriately specified within the above range. As an example, the position of the inner elastic member 61 in the width direction WD is preferably within 10 mm, more preferably within 7.5 mm, from the blocking position (the boundary between the root portion 65 and the middle portion 68 ) in the width direction WD. In addition, when the position of the front end of the product in the front-rear direction LD is set to 0%, and the position of the rear end of the product is set to 100%, it is preferable that the front end of the part stretched and contracted by the inner elastic member 61 is located at 20% to 30%. range, and the rear end of the part stretched by the inner elastic member 61 is located in the range of 20% to 30%. In the case where a narrower portion 56n narrower than the front and rear sides is formed in the middle of the absorber 56 in the front-back direction LD (in particular, in the range in the front-back direction LD including the crotch portion M) as shown in the figure, The inner elastic member 61 is preferably disposed so as to pass through the narrowed portion 56n. Since the narrowed portion 56n is a portion without the absorber 56, its rigidity is lower than that of the portion with the absorber 56, and it is easily deformed. Therefore, if the inner elastic member 61 is provided so as to pass through this position, the portion serving as the base of the upright gathers 60 will be more likely to incline.

The inner elastic member 61 may be provided between the liquid-impermeable sheet 11 and the exterior nonwoven fabric 12 in addition to being provided between the packaging sheet 58 and the liquid-impermeable sheet 11 . In addition to providing only one inner elastic member 61 on each side as shown in the figure, a plurality of inner elastic members 61 may be provided on each side at intervals in the width direction.

As the inner elastic member 61 , an elastic member such as an elongated rubber such as a filament, a rope, or a belt can be used. In addition to providing only one inner elastic member 61 on each side as shown in the figure, a plurality of inner elastic members 61 may be provided on each side. The elongation of the inner elastic member 61 in the unfolded state can be appropriately specified, preferably about 160%-240%, more preferably 180%-220%. When synthetic sericin such as spandex is used as the inner elastic member 61 , the thickness thereof is preferably 400 dtex to 700 dtex, more preferably 500 dtex to 650 dtex.

The part where the contraction force acts on the inner elastic member 61 (the part where the inner elastic member 61 is shown in the figure) may be the same as the existing part of the inner elastic member 61, or may be shorter. That is, the inner elastic member 61 exists on the front side, the rear side, or both sides of the contraction force acting part of the inner elastic member 61. 61, or cut the inner elastic member 61 finely at one or more places, or both, so that the contraction force does not work (substantially equal to no elastic member), so that the part where the contraction force acts is smaller than the The existing portion of the inner elastic member is shorter.

(lateral plane folds) An outer elastic member 64 may also be provided on the outside of the blocking position in the width direction WD of each side wing portion SF, and the leg circumference portion of each side wing portion SF is combined with the outer elastic member 64 by the contraction force of the outer elastic member 64. Shrink, and can be stretched together with the outer elastic member 64 (also can be so-called planar pleats). The outer elastic member 64 can also be omitted.

The outer elastic member 64 may be provided between the liquid-impermeable sheet 11 and the exterior nonwoven fabric 12 in the side flap SF in addition to being provided between the gather sheet 62 and the liquid-impermeable sheet 11 as shown in the figure. between. In addition to providing only one outer elastic member 64 on each side as shown in the figure, a plurality of outer elastic members 64 may be provided on each side at intervals in the width direction.

As the outer elastic member 64 , an elastic member such as a string-shaped, rope-shaped, belt-shaped, elongated rubber or the like can be used. The outer elastic member 64 may be provided in plural on each side in addition to only one being provided on each side as shown in the figure. The elongation of the outer elastic member 64 in the unfolded state can be appropriately specified, preferably about 170%-250%, more preferably 190%-230%. When synthetic sericin such as spandex is used as the outer elastic member 64, the thickness thereof is preferably 400 dtex to 700 dtex, more preferably 500 dtex to 650 dtex.

The portion where the contraction force acts on the outer elastic member 64 (the portion of the outer elastic member 64 shown in the figure) may be the same as the existing portion of the outer elastic member 64, or may be shorter. That is, the outer elastic member 64 exists on the front side, the rear side, or both sides of the shrinkage force acting part of the outer elastic member 64, but it can also be fixed by clamping the outer elastic member outside the shrinkage force acting part. 64 sheet material, or the outer elastic member 64 is finely cut at one or more places, or both so that the contraction force does not work (substantially equal to no elastic member), so that the part where the contraction force acts is larger than the outer part The existing portion of the elastic member 64 is shorter.

＜Explanation of terms used in this manual＞ When the following terms are used in the specification, unless otherwise specified in the specification, they have the following meanings.

The so-called "MD direction" and "CD direction" refer to the traveling direction (MD direction) and the transverse direction (CD direction) perpendicular to it in the manufacturing equipment. Either one becomes the front and rear direction of the product, and the other becomes the width of the product direction. The MD direction of the nonwoven fabric is the direction of fiber alignment of the nonwoven fabric. The so-called fiber orientation refers to the direction along which the fibers of the non-woven fabric are. For example, it can be measured by the fiber orientation test method using the zero-distance tensile strength of TAPPI standard method T481, or according to the tensile strength in the front-back direction and the width direction. It can be judged by a simple measurement method to determine the direction of fiber alignment.

． The so-called "front-rear direction" means the direction (longitudinal direction) indicated by symbol LD in the figure, and the so-called "width direction" means the direction (left-right direction) indicated by WD in the figure, and the front-rear direction is perpendicular to the width direction.

． The so-called "front side" means the side close to the wearer's skin when worn, and the so-called "back side" means the side away from the wearer's skin when worn.

． The so-called "surface" means the surface of the member that is close to the wearer's skin when worn, and the so-called "back" means the surface that is away from the wearer's skin when worn.

The "expanded state" means a state in which it is relaxed and flat without contraction (including all contractions such as contraction by elastic members).

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

"Artificial urine" is made by mixing urea: 2wt%, sodium chloride: 0.8wt%, calcium chloride dihydrate: 0.03wt%, magnesium sulfate heptahydrate: 0.08wt%, and ion-exchanged water: 97.09wt% , as long as there is no special description, it is used at a temperature of 37 degrees.

"Gel strength" is measured as follows. 1.0 g of superabsorbent polymers were added to 49.0 g of artificial urine, and stirred with a stirrer. Place the generated gel in a constant temperature and humidity tank at 40°C x 60%RH for 3 hours, then return to normal temperature, and use a curd meter (manufactured by I.techno Engineering: Curdmeter-MAX ME-500) to measure the gel strength.

"Basis weight" is determined as follows. After the sample or test piece is pre-dried, it is placed in a laboratory or device in a standard state (the test site is a temperature of 23°C ± 1°C, and a relative humidity of 50% ± 2%), and adjusted to a constant state. Pre-drying refers to making the sample or test piece constant in an environment with a temperature of 100°C. Furthermore, pre-drying may not be performed on fibers having a nominal moisture content of 0.0%. Using the template (100 mm x 100 mm) for sample collection, cut out a sample with a size of 100 mm x 100 mm from the test piece in a constant state. Measure the weight of the sample and multiply it by 100 times to calculate the weight per square meter as the basis weight.

"Thickness" is automatically measured under the conditions of load: 0.098N/cm ² and compression area: 2cm ² using an automatic thickness measuring device (KES-G5 handheld compression testing machine).

"Water absorption" is measured by JIS K7223-1996 "Test method for water absorption of superabsorbent resin".

"Water absorption speed" is set as "time to end point" when JIS K7224-1996 "Water absorption speed test method of super absorbent resin" is performed using 2 g of superabsorbent polymer and 50 g of physiological saline.

Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state, not in the naturally long state.

In the absence of records related to the environmental conditions of the test or measurement, it is deemed that the test or measurement is in a standard state (the test site is a laboratory with a temperature of 23°C±1°C and a relative humidity of 50%±2%) or within the device.

(industrial availability) The present invention is not limited to the above-mentioned general strip-type disposable diapers, as long as the object of use has erected folds, it can of course be used for all disposable diapers of pad type or pants type, and can also be used for other absorbent materials such as menstrual sanitary napkins. sex items. Especially for disposable diapers for low birth weight infants, a weak but soft fit is preferable to a firm fit. Therefore, the above-mentioned raised gathers having free portions are suitable for use in disposable diapers for low birth weight infants.

11: Liquid-impermeable sheet 12: Non-woven fabric for exterior decoration 12T: Target Department 13: Connecting belt 13A: Connecting part 30: top sheet 50: Absorb Elements 56: Absorber 56n: narrowing part 58: Packaging sheet 60: erect folds 61: inner elastic member 62: Wrinkled sheet 62f: outer layer 62n: inner layer 63: Wrinkled elastic member 64: Outer elastic member 65: root 66: body part 67: front end 68: middle part 69: Rear end BP: fixed part FP: Ministry of Freedom LD: Front and rear direction M: Intersection WD: width direction

Fig. 1 is a plan view showing the unfolded state of the inner surface of the connecting type disposable diaper. Fig. 2 is a plan view showing the unfolded state of the outer surface of the connecting type disposable diaper. Figure 3 is a sectional view of line 6-6 in Figure 1. Figure 4 is a sectional view of line 7-7 in Figure 1. Fig. 5 is a sectional view of line 8-8 in Fig. 1. Figure 6 is a sectional view of line 5-5 in Figure 1. Fig. 7 is an enlarged sectional view showing the main part of the erected folds. Fig. 8 is an enlarged sectional view showing the main part of the vertical folds. Fig. 9 is a perspective view schematically showing the inner surface in a worn state. Fig. 10 is a plan view showing the unfolded state of the inner surface of the connecting type disposable diaper. Fig. 11 is a plan view showing the unfolded state of the inner surface of the connecting type disposable diaper.

Domestic deposit information (please note in order of depositor, date, and number) none Overseas storage information (please note in order of storage country, institution, date, and number) none

11: Liquid-impermeable sheet

13: Connecting belt

13A: Connecting part

13C: base end

30: top sheet

56: Absorber

56n: narrowing part

58: Packaging sheet

60: erect folds

60B: imaginary line

61: inner elastic member

62: Wrinkled sheet

63: Wrinkled elastic member

64: Outer elastic member

65: root

66: body part

67: front end

68: middle part

69: Rear end

70: narrow side edge

71: lower edge

B: dorsal part

BP: fixed part

EF: End wing

F: ventral part

FP: Ministry of Freedom

L: full length

LD: Front and rear direction

M: Intersection

SF: Flank

WD: width direction

WP: wing part

y1: size

Claims (6)

An absorbent article characterized by having: absorber; a liquid-permeable top sheet disposed on the surface side of the absorbent body; and Standing pleats are respectively arranged on both sides of the width direction of the surface of the aforementioned top sheet; The above-mentioned standing pleats have: a root portion installed on the outside of the width direction of an imaginary line, the above-mentioned imaginary line passes through the blocking positions on both sides of the width direction of the surface of the top sheet and is continuous in the front-rear direction; The inner edge of the aforementioned root in the width direction is folded back and extends toward the inner side of the width direction; The aforementioned body portion has: a front end portion and a rear end portion having a fixing portion fixed to the aforementioned top sheet; and a middle portion located between the front end portion and the rear end portion and not fixed to the aforementioned top sheet; On at least the top end of the middle part, a slender elastic member with folds along the front-rear direction is installed, The middle portion is contracted together with the gather elastic member by the contraction force of the gather elastic member, and can be extended together with the gather elastic member, At least one of the front end portion and the rear end portion at the inner end portion in the width direction is provided with a free portion that is not fixed to the top sheet continuously from the middle portion, and the front end portion and the rear end portion The above-mentioned free part of the end part becomes the fixed part, The width of the aforementioned free portion is 1/6~1/3 of the width of the aforementioned middle portion, and the dimension of the aforementioned free portion in the front-back direction is 1~9.5 times of the width of the aforementioned free portion. The absorbent article described in claim 1, wherein the width of the free portion is 3.5 mm or more, The intermediate portion has the gather elastic member in a front end region having a width equal to that of the free portion, and does not have the gather elastic member outside the front end region. The absorbent article according to claim 1 or 2, wherein in the region overlapping the back side of the middle part in the unfolded state, in the root side region equal to the width of the fixing part, the area is thicker than the top sheet. The backrest side has an elongated inner elastic member along the front-rear direction, The root side region can be contracted together with the inner elastic member by the contraction force of the inner elastic member, and can be extended together with the inner elastic member. The absorbent article described in claim 3, wherein the absorbent body has a narrowed portion in the middle of the front-to-back direction that is narrower than the front and back sides thereof, The aforementioned inner elastic member is arranged to pass through the narrowed portion. The absorbent article according to any one of claims 1 to 4, wherein both the front end portion and the rear end portion have the free portion, The width of the aforementioned free portion of the aforementioned front end portion is wider than the width of the aforementioned free portion of the aforementioned rear end portion. The absorbent article described in any one of claims 1 to 5 is a disposable diaper for low birth weight infants.

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