JP2019208803A - Absorbent article - Google Patents

Abstract

To increase an absorption speed, to prevent backflow, and to improve wear feeling by thinning.SOLUTION: A pad 1 is provided with an absorber 4 composed of a lower layer absorber 10 which contains pulp fiber and superabsorbent polymer and an upper layer absorber 11 which is arranged on the skin side of the lower layer absorber 10 and contains pulp fiber and superabsorbent polymer. The upper layer absorber 11 extends along a longitudinal direction, is arranged intermittently across a plurality of strips in the width direction, and content ratio of the superabsorbent polymer in the upper layer absorber 11 is greater than content ratio of the superabsorbent polymer in the lower layer absorber 10. The content ratio of the superabsorbent polymer in the upper layer absorber 11 ranges from 50 to 90 weight%, the content ratio of the superabsorbent polymer in the lower layer absorber 10 ranges from 5 to 50 weight%, and the difference between the content ratio of the superabsorbent polymer in the upper layer absorber 11 and the content ratio of the superabsorbent polymer in the lower layer absorber 10 is between 10 and 85.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an absorbent article such as a disposable diaper, a sanitary napkin, a panty liner, an incontinence pad, and more specifically, an upper layer absorbent body and a lower layer absorbent body, and the upper layer absorbent body extends in the longitudinal direction and extends in the width direction. The present invention relates to an absorbent article including an absorbent body intermittently disposed over a plurality of strips.

  Conventionally, as the absorbent article, between the impervious back sheet such as polyethylene sheet or polyethylene sheet laminated nonwoven fabric and the liquid permeable front sheet such as nonwoven fabric or liquid permeable plastic sheet, between fibers of pulp fibers. In addition, there is known an intervening absorbent body in which a superabsorbent polymer is held.

  In recent years, in addition to the function of reliably absorbing and retaining excreted body fluid, the absorbent body is required to be thin and excellent in a feeling of wearing and with little reversal after liquid absorption.

  As an absorbent article including such an absorbent body, the following Patent Document 1 includes an absorbent body having a groove portion that forms an opening on at least one surface, and a surface perpendicular to the thickness direction of the absorbent body of the groove portion. Is disclosed in which the opening width is reduced as it goes from one surface to the other surface, so that it can be easily bent in response to changes in the body shape and posture of the wearer and the fit is improved.

  Further, in Patent Document 2 below, a side area in the absorbent body width direction, which has a dense structure of fibers in the central area in the absorbent body width direction of the excretory part facing portion, is located on both the left and right sides of the central area, A low-density part having the lowest density in the excretory part-facing part is included, and the density structure of the fibers is a medium-density part having a higher density than the low-density part, and a high-density part having a higher density than the medium-density part The medium density part and the high density part are each formed to extend in the longitudinal direction of the absorber, and in the fiber dense structure, a plurality of medium density parts and a plurality of medium density parts are formed. By providing the high-density part and the absorbent body arranged alternately in the width direction of the absorbent body, the liquid drawability from the topsheet to the absorbent body is improved, and the liquid residue is hardly generated on the topsheet. Disclosed is a product that has a high dry feeling when used. To have.

Special table 2010-273842 gazette JP 2011-120698 A

  However, in the absorbent articles described in Patent Documents 1 and 2, since the composition in the thickness direction of the absorber is almost uniform, it must be formed with a certain thickness to ensure a sufficient amount of absorption. There is a possibility that the thinning cannot be achieved and the pulp fiber has a small liquid holding power, so that the absorbent body may reverse after absorption.

  In general, it is known that by reducing the content ratio of pulp fibers and increasing the content ratio of the superabsorbent polymer, the absorber can be made thinner, the wearing feeling can be improved, and the reversion can be improved. For this reason, in the conventional absorbent article, an absorbent body having a two-layer structure of an upper layer absorber and a lower layer absorber is used, the amount of pulp fibers in the upper layer absorber is reduced as much as possible, and the content ratio of the superabsorbent polymer By increasing the height, the function of reducing the thickness and preventing the reversion is combined.

  However, the absorbent article having such a structure has a problem that the absorption speed of the superabsorbent polymer is slow, so that a large amount of body fluid is discharged at one time and the body fluid overflows to the surface and is likely to leak. . In particular, during repeated drainage, the superabsorbent polymer absorbs water and swells with the previous drainage, and the gap between the particles is narrowed, so that the liquid cannot pass through, so-called gel blocking. There was a problem that body fluid overflowed on the surface and leakage was likely to occur.

  Moreover, in order to prevent gel blocking in the upper-layer absorbent body, it may be possible to provide an opening at a site corresponding to the body fluid discharge part of the upper-layer absorbent body. When body fluid is discharged to a position, it cannot be absorbed quickly, and the absorption speed may be slow.

  Therefore, a main object of the present invention is to provide an absorbent article that can increase the absorption speed more reliably, prevent reversal, and improve the wearing feeling by reducing the thickness.

In order to solve the above-mentioned problems, the present invention according to claim 1 includes a lower layer absorbent comprising pulp fibers and a superabsorbent polymer, and is disposed on the skin side of the lower layer absorbent, and includes pulp fibers and a superabsorbent polymer. An absorbent article provided with an absorber composed of an upper-layer absorber,
The upper layer absorber extends along the longitudinal direction and is intermittently arranged over a plurality of strips with a gap in the width direction, and the content ratio of the superabsorbent polymer in the upper layer absorber is the lower layer absorber. The absorbent article is characterized by being higher than the content ratio of the superabsorbent polymer.

  In the first aspect of the present invention, the upper absorbent body extends along the longitudinal direction and is intermittently disposed over a plurality of strips with a gap in the width direction. The body fluid easily flows into the lower layer absorber through the gap formed in the bottom. In the lower layer absorber, the content ratio of the superabsorbent polymer is set lower than the content ratio of the superabsorbent polymer in the upper layer absorber, so that the bodily fluid is absorbed by the lower layer absorber due to the capillary action of the pulp fibers. It is easy and the absorbed body fluid is easy to diffuse inside the lower layer absorber. For this reason, the absorption speed of a bodily fluid can be increased.

  In addition, by increasing the content ratio of the superabsorbent polymer in the upper absorbent body to be higher than the content ratio of the superabsorbent polymer in the lower absorbent article, the water holding power on the skin contact surface side is increased, It is possible to prevent the absorbed body fluid from returning after being absorbed.

  Furthermore, since the content ratio of the superabsorbent polymer is high and the content ratio of the pulp fiber is low in the upper layer absorbent body, the thickness of the absorbent body is reduced, and the wearing feeling can be improved.

  As this invention which concerns on Claim 2, the content rate (X) of the said super absorbent polymer in the said upper layer absorber is 50 to 90 weight%, and the content rate (Y) of the super absorbent polymer in the said lower layer absorber is The difference (X−Y) between the content ratio of the superabsorbent polymer in the upper layer absorbent body and the content ratio of the superabsorbent polymer in the lower layer absorbent body is 10 to 85%. The absorbent article described is provided.

  In the invention of claim 2, the content ratio of the superabsorbent polymer in the upper layer absorbent body and the lower layer absorbent body is specified, and the difference in the content ratio is specified, thereby improving the absorption speed and preventing the reversion. The effect is balanced.

  As the present invention according to claim 3, the upper-layer absorber is disposed over the entire length of the lower-layer absorber, and a gap formed between adjacent upper-layer absorbers is continuous over the entire length of the lower-layer absorber. An absorbent article according to any one of claims 1 and 2 is provided.

  In the invention described in claim 3, the upper layer absorber is disposed over the entire length of the lower layer absorber, and a gap formed between adjacent upper layer absorbers continues over the entire length of the lower layer absorber. Therefore, even if the excretion position is slightly shifted depending on the wearer's body shape and posture, the mounting position of the absorbent article, etc., body fluid passes through the gap between adjacent upper layer absorbents to the lower layer absorbent. It is easy to move quickly and the absorption speed can be increased more reliably.

  As the present invention according to claim 4, the absorptivity according to any one of claims 1 to 3, wherein the upper-layer absorber is intermittently arranged in two strips with a gap in the center in the width direction of the lower-layer absorber. Articles are provided.

  In the invention of claim 4, the upper absorbent body is intermittently arranged in two strips with a gap in the middle in the width direction of the lower absorbent body, so that a gap between adjacent upper absorbent bodies is formed. Since it is formed at the central portion in the width direction of the lower layer absorbent, the body fluid easily moves to the lower layer absorber through the gap at the central portion in the width direction.

As the present invention according to claim 5, the lower-layer absorbent body is formed with a leg-cut-out portion in which both side portions are cut out in a portion corresponding to the crotch portion of the wearer,
The said upper layer absorber is arrange | positioned in the width direction inner side from the said leg periphery notch part, and is not arrange | positioned in the both sides of the said lower layer absorber containing the said leg periphery notch part. An absorbent article is provided.

  In the invention according to claim 5, in the case where notched portions around the legs are formed on both sides of the lower layer absorbent body, the upper layer absorbent body is disposed on the inner side in the width direction from the notched portion around the leg, By not arranging on both side portions of the lower layer absorber including the portion, the lower layer absorber portion where the upper layer absorber is not laminated on the skin side is provided on both sides of the region before and after the leg notch. For this reason, in the region before and after the notch around the leg, when body fluid flows outward in the width direction of the upper layer absorber, it is quickly absorbed by the lower layer absorber and leakage can be prevented.

As the present invention according to claim 6, the lower-layer absorbent body is formed with a notch around the leg with both sides cut out in a portion corresponding to the crotch portion of the wearer,
The said upper layer absorber is arrange | positioned separately in the both sides of the said lower layer absorber containing the said leg periphery notch part, respectively by the front side and the rear side of the said leg periphery notch part. An absorbent article as described in 1 above is provided.

  In the invention of claim 6 above, when the leg periphery notch is formed on both sides of the lower layer absorber, the upper layer absorber is cut around the leg on both sides of the lower layer absorber including the leg notch. Since they are arranged separately on the front side and the rear side of the notch part, the water holding power on the skin contact surface side of this part is increased, and it is possible to prevent the body fluid absorbed by the lower layer absorbent from returning after being absorbed. It becomes like this.

  As described above in detail, according to the present invention, the absorption speed can be more reliably increased, the reverse movement can be prevented, and the wearing feeling can be improved by reducing the thickness.

It is a partially broken development view of pad 1 concerning the present invention. It is the II-II arrow directional view of FIG. It is the III-III arrow directional view of FIG. 4 is a plan view of the absorber 4. FIG. FIG. 5 is a view taken along line VV in FIG. 4. It is the VI-VI line arrow directional view of FIG. It is a top view of absorber 4 concerning a modification. It is a VIII-VIII arrow directional view of FIG. It is the IX-IX arrow directional view of FIG. It is a perspective view which shows the continuous body 10A of a lower layer absorber, and the continuous body 11A of an upper layer absorber.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Example of basic pad structure>
The pad 1 according to the present invention is a pad such as a urine collecting pad that is used by being attached to a skin contact surface such as an underwear or a paper diaper. As shown in FIGS. 2, a surface sheet 3 that forms a skin contact surface and allows urine to pass through quickly, an absorbent body 4 interposed between the sheets 2 and 3, and an outermost surface (non-skin contact surface) of the pad 1 ) And the left and right provided in a predetermined section in the front-rear direction including at least the wearer's urination port and projecting to the skin side. A pair of three-dimensional gathers BS, mainly composed of side non-woven fabrics 6 and 6 forming BS, and around the absorber 4, the top and bottom edges of the leak-proof sheet 2, the top sheet 3 and the exterior sheet 5 The outer edge is hot-melt adhesive or The leak-proof sheet 2, the surface sheet 3, the exterior sheet 5, and the side nonwoven fabric 6 that are joined by joining means such as a to-seal and an ultrasonic seal and extend laterally from the absorbent body 4 at both side edges thereof are hot melted. It is joined by joining means such as an adhesive, heat seal, ultrasonic seal and the like.

  The leak-proof sheet 2 is made of a sheet material having at least water shielding properties such as polyethylene, but recently has a tendency to use a material having moisture permeability from the viewpoint of preventing stuffiness. The water- and moisture-permeable sheet material is a microporous material obtained by melting and kneading an inorganic filler in an olefin-based resin such as polyethylene or polypropylene to form a sheet, and then stretching in a uniaxial or biaxial direction. A sheet is preferably used. As the leak-proof sheet 2, a polylaminated nonwoven fabric in which a plastic film and a nonwoven fabric are laminated may be used.

  Next, a porous or non-porous nonwoven fabric or a porous plastic sheet is preferably used as the top sheet 3. The non-woven fabric material fibers can be synthetic fibers such as polyethylene or polypropylene, synthetic fibers such as polyester and polyamide, recycled fibers such as rayon and cupra, natural fibers such as cotton, and spunlace. A nonwoven fabric obtained by an appropriate processing method such as a method, a spun bond method, a thermal bond method, a melt blown method, or a needle punch method can be used. Among these processing methods, the spunlace method is excellent in terms of flexibility and drapeability, and the thermal bond method is excellent in terms of bulkiness and high compression recovery. When a large number of through holes are formed in the surface sheet 3, body fluid is quickly absorbed, and the dry touch properties are excellent. The nonwoven fiber may be either a long fiber or a short fiber, but it is preferable to use a short fiber in order to give a towel texture. In order to facilitate the embossing treatment, it is preferable to use an olefin fiber such as polyethylene or polypropylene having a relatively low melting point. Moreover, a core-sheath fiber, a side-by-side fiber, or a split fiber composite fiber having a fiber having a high melting point as a core and a fiber having a low melting point as a sheath can also be suitably used.

The exterior sheet 5 covers the leak-proof sheet 2 so that the outer surface of the pad 1 looks and feels like a cloth. The exterior sheet 5 is preferably formed of a nonwoven fabric. The raw material fibers can be synthetic fibers such as polyethylene or polypropylene such as olefins, polyesters, polyamides, etc., recycled fibers such as rayon and cupra, and natural fibers such as cotton. The processing method is the spunlace method The spun bond method, the thermal bond method, the air through method, the needle punch method and the like can be used. However, a long fiber nonwoven fabric such as a spunbond nonwoven fabric, an SMS nonwoven fabric, or an SMMS nonwoven fabric is preferable from the viewpoint that both feel and strength can be achieved.
In addition to using a single nonwoven fabric, a plurality of nonwoven fabrics can also be used. When a plurality of nonwoven fabrics are used, it is preferable to fix the nonwoven fabrics together with an adhesive such as hot melt. Moreover, when using a nonwoven fabric, the fiber basis weight is 10-50 g / m < ² >, Especially 15-30 g / m < ² > is preferable.

  One or a plurality of temporary fixing layers (not shown) are formed on the non-use surface side (outer surface) of the exterior sheet 5, and the pad 1 is fixed to an undergarment or a paper diaper when worn on the body. Yes. As the temporary fixing layer, a mechanically bonded hook material or an adhesive may be used.

In the illustrated example, the exterior sheet 5 is slightly wider than the width of the polymer sheet 4, and the both side portions are wound around the side edges of the leak-proof sheet 2 and the surface sheet 3 to the skin side of the surface sheet 3. The outer side in the width direction of the top sheet 3 is penetrated by the side nonwoven fabric 6 extending from the surface of both side surfaces of the top sheet 3, specifically urine, etc., on the outer surface side of the exterior sheet 5 extending to the skin side. A side nonwoven fabric 6 made of a nonwoven fabric material subjected to appropriate water-repellent treatment or hydrophilic treatment is disposed in accordance with the purpose of preventing it from occurring or enhancing the feeling of touch. The side nonwoven fabric 6 can be made of natural fiber, synthetic fiber, regenerated fiber, or the like and formed by an appropriate processing method. Preferably, the side nonwoven fabric 6 eliminates the feeling of stickiness and prevents stuffiness. For this reason, it is preferable to use a non-woven fabric with reduced basis weight and air permeability. Specifically, it is desirable to use a nonwoven fabric prepared with a basis weight of 13 to 23 g / m ² , and silicon-based, paraffin-based, alkylchromic chloride-based water repellents, etc. in order to reliably prevent permeation of body fluids. A water repellent nonwoven fabric coated with is preferably used.

  The inner side portion of the side nonwoven fabric 6 is folded substantially double, and inside this double sheet, one or a plurality of both ends or appropriate positions in the longitudinal direction are fixed to the intermediate portion in the height direction, In the illustrated example, three thread-like elastic elastic members 7, 7,... Are arranged in a state where both ends or appropriate positions in the longitudinal direction are fixed. As shown in FIG. 3, the double sheet portion is attached to the absorbent body 4 side in a state where it is folded once outward and laminated, thereby at least including the urination port of the wearer. As shown in FIG. 2 within a predetermined section in the direction, the three-dimensional gathers BS and BS standing on the skin side are formed in a pair of left and right.

<Absorber>
The absorbent body 4 interposed between the leak-proof sheet 2 and the top sheet 3 is disposed on the skin side of the lower layer absorbent body 10 including the pulp fiber and the superabsorbent polymer, and the pulp fiber. And an upper layer absorbent body 11 containing a superabsorbent polymer, and has a function of absorbing and holding body fluids. The absorbent body 4 is preferably surrounded by a core wrap sheet 8 made of a nonwoven fabric or crepe paper as shown in the illustrated example.

  The lower layer absorbent body 10 is mainly composed of pulp fibers and a super absorbent polymer, and is disposed adjacent to the non-skin contact surface side of the upper layer absorbent body 11. The superabsorbent polymer is mixed in the pulp fibers constituting the lower layer absorbent body 10 as, for example, granular powder and held between the fibers of the pulp fibers. Examples of the pulp fiber include cellulose fibers such as chemical pulp obtained from wood and dissolved pulp, and artificial cellulose fibers such as rayon and acetate. Softwood pulp having a longer fiber length functions than hardwood pulp. And is preferably used in terms of price.

  Examples of the superabsorbent polymer include a cross-linked polyacrylate, a self-crosslinked polyacrylate, a saponified acrylate-vinyl acetate copolymer cross-linked product, a cross-linked isobutylene / maleic anhydride copolymer, Examples include cross-linked polysulfonates, and partially cross-linked water-swellable polymers such as polyethylene oxide and polyacrylamide. Among these, those based on acrylic acid or acrylate that are excellent in water absorption and water absorption speed are preferred. In the production process of the highly water-absorbing polymer having the water-absorbing performance, the water-absorbing force and the water-absorbing speed can be adjusted by adjusting the crosslinking density and the crosslinking density gradient.

The basis weight of the pulp fiber in the lower layer absorbent body 10 is 50 to 300 g / m ² , preferably 80 to 220 g / m ^2, and the basis weight of the superabsorbent polymer is 30 to 180 g / m ² , preferably Is preferably 50 to 160 g / m ² . The basis weight is calculated by measuring the weight of a test piece cut into a 50 × 50 mm square and dividing by the area (the same applies hereinafter). The basis weights of these pulp fibers and the superabsorbent polymer do not need to be constant, and may be changed depending on the site of the absorber. For example, in a region corresponding to the body fluid discharge portion H of the wearer, a high absorption portion having a high basis weight of pulp and a superabsorbent polymer is formed, or between adjacent upper layer absorbers 11 and 11 as described in detail later. In order to improve the body fluid drawability in the portion overlapping with the gap 13 formed in the layer or the portion where the upper layer absorbent body 11 is not laminated, the basis weight of the superabsorbent polymer may be lowered and the basis weight of the pulp fiber may be increased. . The body fluid discharge part H is mainly a part corresponding to the wearer's urination opening part, and the area of the human body is different between men and women, but as shown in FIG. This is a region in the center portion in the width direction on the front side of the center portion in the longitudinal direction of the portion where the leg notch portions 12 described later are formed on both sides.

  The content ratio (Y) of the superabsorbent polymer in the lower layer absorbent body 10 is 5 to 50% by weight, preferably 10 to 40% by weight, more preferably 10 to 30% by weight. The content ratio is a ratio of the weight of the superabsorbent polymer contained in the lower layer absorbent body 10 to the total weight of the lower layer absorbent body 10. Therefore, when the lower layer absorber 10 is composed of pulp fibers and a superabsorbent polymer, if the content ratio of the superabsorbent polymer in the lower layer absorber 10 is 20% by weight, the remaining 80% by weight is pulp fibers. . In the lower layer absorbent body 10, a large amount of pulp fiber is blended by keeping the content ratio of the superabsorbent polymer low, and the capillary fiber action of the pulp fiber increases the absorption speed of the initial absorption of the body fluid, and the inside of the lower layer absorbent body 10. Improves the diffusion of body fluids.

  The lower layer absorber 10 has a thickness of 1.5 to 3.5 mm, preferably 2.0 to 3.0 mm. If it is smaller than 1.5 mm, the body fluid absorption capacity is small, and there is a risk of overflowing the surface when a large amount of body fluid is discharged at once. On the other hand, if it is thicker than 3.5 mm, the absorber 4 cannot be thinned, and the wearing feeling deteriorates. The thickness is measured by a constant pressure thickness measuring instrument digital type FFD-7 manufactured by Ozaki Seisakusho (the same applies hereinafter).

Further, the density (average density) of the lower layer absorber 10 is preferably 0.02 to 0.35 g / cm ³ . When it is less than 0.02 g / cm ³ , the absorption speed of body fluid is improved, but since the interfiber gap is large, capillary action is difficult to occur, and the diffusibility of the liquid inside the absorber is reduced. On the other hand, when it is larger than 0.35 g / cm ³ , the absorption speed at the initial stage of absorption of body fluid is lowered. The density is calculated from the basis weight / T0 by measuring the thickness T0 at a pressure of 0.5 gf / cm ² using a KES compression tester manufactured by Kato Tech Co., Ltd. (the same applies hereinafter).

  Synthetic fibers may be mixed in the lower layer absorbent body 10. As the synthetic fiber, for example, polyolefins such as polyethylene or polypropylene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides such as nylon, and copolymers thereof can be used. It may be a mixture. In addition, a composite fiber such as a core-sheath fiber, a side-by-side fiber, or a split fiber having a fiber having a high melting point as a core and a fiber having a low melting point as a sheath can also be used. In the case of a hydrophobic fiber, it is desirable to use a synthetic fiber that has been surface-treated with a hydrophilizing agent so as to have an affinity for body fluids.

  The lower-layer absorber 10 is continuously arranged over almost the entire surface of the absorber 4 and constitutes substantially the outer edge of the absorber 4 in plan view. As the planar shape of the lower layer absorbent body 10, a known shape can be widely adopted as long as it is a vertically long shape in the front-rear direction, but as shown in FIG. By forming a pair of left and right leg notches 12, 12 that are notched in an arc shape, trapezoidal shape, triangle shape, etc. that bulge inwardly, the leg notch portions 12, 12 are constricted in the width direction. Further, it is preferably formed in a substantially hourglass shape in plan view.

  The upper layer absorbent body 11 disposed adjacent to the skin contact surface side of the lower layer absorbent body 10 is composed of pulp fibers and a super absorbent polymer. The superabsorbent polymer is mixed in the pulp fibers constituting the upper layer absorbent body 11 as, for example, granular powder. As the pulp fiber and the superabsorbent polymer, those mentioned in the description of the lower layer absorbent body 10 can be used without limitation.

The basis weight of the pulp fiber in the upper absorbent body 11 is 5 to 150 g / m ² , preferably 30 to 100 g / m ^2, and the basis weight of the superabsorbent polymer is 50 to 250 g / m ² , preferably Is preferably 100 to 200 g / m ² .

  The content ratio (X) of the superabsorbent polymer in the upper layer absorbent body 11 is 50 to 90% by weight, preferably 60 to 90% by weight, and more preferably 70 to 90% by weight. If it is less than 50% by weight, the water retention capacity of the upper layer absorbent body 11 is too small, and the body fluid absorbed by the lower layer absorbent body 10 may return to the skin side. On the other hand, when it is larger than 90% by weight, the graininess of the superabsorbent polymer is easy to feel on the skin when worn, the feel of wearing becomes poor, and the superabsorbent polymer is hard to be fixed between the fibers of the pulp fiber. Breakage of the water-absorbing polymer and loss of the superabsorbent polymer.

  The difference (X−Y) between the content ratio (X) of the superabsorbent polymer in the upper layer absorbent body 11 and the content ratio (Y) of the superabsorbent polymer in the lower layer absorbent body 10 is 10 to 85, preferably It is good to set it as 20-80, More preferably 40-80. Thereby, the absorption speed of the bodily fluid in the lower layer absorber 10 and the effect of preventing the return in the upper layer absorber 11 are exhibited in a well-balanced manner. The difference (X−Y) is a value (unit: wt%) of the content ratio (X) of the superabsorbent polymer in the upper layer absorber 11 and the content ratio (Y of the superabsorbent polymer in the lower layer absorber 10). ) (Unit:% by weight) is simply subtracted.

  The upper absorber 11 has a thickness of 0.5 to 1.5 mm, preferably 0.75 to 1.25 mm. If it is less than 0.5 mm, the absorption capacity of the body fluid is small, and it may not be possible to prevent the body fluid absorbed by the lower layer absorbent body 10 from returning to the skin side. On the other hand, if the thickness is greater than 1.5 mm, the absorber 4 cannot be thinned, and the wearing feeling is deteriorated.

The density (average density) of the upper-layer absorber 11 is preferably 0.05 to 1.0 g / cm ³ .

  As shown in FIGS. 4 to 6, the upper layer absorbent body 11 extends along the longitudinal direction on the skin side surface of the lower layer absorbent body 10 and is intermittently disposed in the width direction over a plurality of strips. . That is, a plurality of upper layer absorbent bodies 11 having a predetermined width are arranged on the skin side surface of the lower layer absorbent body 10 with a predetermined interval, thereby being arranged in a vertical stripe shape as a whole.

  Between the adjacent upper layer absorbers 11, 11, a gap 13 in which the upper layer absorber 11 does not exist is formed. In the gap portion 13, the upper layer absorbent body 11 is not laminated on the skin side surface of the lower layer absorbent body 10, and the lower layer absorbent body 10 is disposed to face the top sheet 3. That is, in the gap portion 13, body fluid excreted on the skin side can be absorbed by the lower layer absorbent body 10 without passing through the upper layer absorbent body 11.

  The upper layer absorber 11 is disposed over the entire length of the lower layer absorber 10, and a gap 13 formed between the adjacent upper layer absorbers 11, 11 is provided continuously over the entire length of the lower layer absorber 10. It is desirable to be able to. That is, adjacent upper layer absorbers 11 are formed by continuously arranging strip-shaped upper layer absorbers 11 formed with substantially equal widths between the front edge and the rear edge of lower layer absorber 10; 11 is formed between the front side edge and the rear side edge of the lower layer absorber 10 continuously. Thus, since the said gap | interval part 13 is provided continuously over the full length of the lower layer absorber 10, even if the excretion position of a bodily fluid shifts a little in the front-back direction, the same effect is always acquired about bodily fluid absorption. It becomes like this. Further, since the gap 13 that is recessed from the upper-layer absorbers 11 on both sides is formed over the entire length of the absorber 4, the pad 1 is touched by hand when attached to the inner surface of the outer such as a paper diaper. Alternatively, the center position of the pad 1 can be easily confirmed visually, and the pad 1 can be reliably attached to the central portion in the width direction of the outer with the gap 13 as a guide. In particular, since the gap portion 13 is formed up to the front end portion and the rear end portion of the absorbent body 4, the pad 1 is formed by aligning the front end portion and the rear end portion of the gap portion 13 with the central portion in the outer width direction. Since it becomes possible to attach to the center part in the width direction of the outer part over the entire length, alignment at the time of attachment becomes very simple.

  The width A per strip of the upper absorbent body 11 is arbitrary as long as it can be arranged in a plurality of strips while forming the gap portion 13 between the leg notches 12 and 12 of the lower absorbent body 10, It is preferable to set it as 10-40 mm. The plurality of upper-layer absorbent bodies 11 may be formed with the same width. For example, the upper-layer absorbent body 11 disposed in the center portion in the width direction is narrowed and disposed on the outer side in the width direction. You may form with the width dimension which changes with places, such as making the upper layer absorber 11 wide.

  The width B of the gap 13 is preferably 10 to 30 mm. When it is smaller than 10 mm, it is difficult for body fluid to move to the lower layer absorbent body 10 through the gap portion 13, and when it is larger than 30 mm, the body fluid absorbed by the lower layer absorbent body 10 easily returns to the skin side through the gap portion 13. Become.

  As an example of an embodiment in which the leg cutout portions 12 and 12 are formed on both sides of the lower layer absorbent body 10, the upper layer absorbent body 11 includes the leg cutout portions as shown in FIG. 4. It can arrange | position to the width direction inner side rather than the parts 12 and 12, and it can be made not to arrange | position to the both sides of the lower layer absorber 10 containing the said leg periphery notch part 12. FIG. In other words, the upper layer absorbent body 11 is disposed only between the notch portions 12 and 12 around the legs of the lower layer absorbent body 10. Thereby, since the part of the lower layer absorber 10 in which the upper layer absorber 11 is not laminated | stacked on the skin side is provided in the both sides of the area | region before and behind the leg periphery notch part 12, the area | region before and behind the said leg periphery notch part 12 is provided. When body fluid flows to the outer side in the width direction of the upper layer absorbent body 11, it is quickly absorbed by the lower layer absorbent body 10, and leakage of body fluid can be prevented. On the other hand, since the upper layer absorbent body 11 is laminated along the longitudinal direction on the skin side of the lower layer absorbent body 10 in the region where the body fluid in the crotch part is easy to diffuse, It can prevent that the bodily fluid absorbed by the absorber 10 returns to the skin side.

  In the embodiment shown in FIG. 4, the upper absorbent body 11 is intermittently arranged in two strips with a space in the middle in the width direction of the lower absorbent body 10, and the longitudinal direction in the middle in the width direction of the lower absorbent body 10. One gap portion 13 is formed continuously over the entire length. By forming the gap 13 at the center in the width direction, the absorption speed of the body fluid can be increased at a position close to the body fluid discharge portion of the wearer.

  As shown in FIG. 4 and FIG. 5, the upper layer absorbent body 11 is arranged at a position where the outer edge in the width direction substantially coincides with the inner edge in the width direction of the notch 12 around the leg. preferable. Thereby, the area of the upper layer absorbent body 11 arranged between the leg cutout portions 12 and 12 can be increased as much as possible, water absorption can be ensured, and the leg cutout portion 12 of the lower layer absorbent body 10 can be secured. Since the body fluid diffused in the vicinity of is absorbed by the upper absorbent body 11 disposed on the skin side surface, leakage from the edge of the leg notch 12 can be reliably prevented.

  Further, the upper layer absorbent body 11 is formed of a straight line having an outer contour line extending in the longitudinal direction on the outer side in the width direction, and the linear outer contour line has a notch 12 around the arc-shaped leg that bulges inward in the width direction. It is preferable to arrange so that it may contact | connect the top part of. That is, by not forming the outer shape line of the upper layer absorbent body 11 in the width direction on the inner side so as to follow the outer shape line of the leg notch portion 12, the absorbent body 4 around the leg is easily deformed. At the same time, the lower layer absorbent body 10 having a high pulp fiber content is easily fitted around the legs, so that the wearing feeling is improved.

  The upper layer absorber 11 can be arranged in various patterns. For example, as shown in FIGS. 7 to 9, it may be arranged not only between the leg notches 12, 12 but also on both sides of the lower layer absorbent body 10 including the leg notches 12. Good. At this time, it is preferable that the both sides of the lower layer absorbent body 10 including the leg notch 12 are arranged separately on the front side and the rear side of the leg notch 12. By disposing the upper layer absorbent body 11 on both side portions of the lower layer absorbent body 10 including the leg notch 12, the water retention power on the skin contact surface side of this portion can be increased. It is possible to prevent the absorbed bodily fluid from returning after the absorption.

  In addition, the upper layer absorbent body 11 disposed between the leg cutout portions 12 and 12 is disposed along the longitudinal direction in the central portion in the width direction of the lower layer absorbent body 10, and one or a plurality of strips are provided on both sides thereof. It may be arranged. Thereby, although the gap | interval part 13 is not formed in the center part of the width direction of the absorber 4, body fluid mainly passes through the gap | interval parts 13 and 13 formed in the both sides of the upper layer absorber 11 arrange | positioned in the center part of the width direction. Can be transferred to the lower layer absorber 10.

  Next, a method for manufacturing the absorber 4 will be described. As shown in FIG. 10, the absorbent body 4 is manufactured by using a predetermined fiber stacking apparatus to manufacture a continuous body 10A of a lower layer absorbent body and a continuous body 11A of an upper layer absorbent body that are continuous in the longitudinal direction. The lower layer absorbent body 10A and the upper layer absorbent body 11A are integrally cut at a predetermined length. In the fiber stacking apparatus for producing the continuous body 10A of the lower layer absorbent body, the fiber stack is formed by continuously forming the absorbent body forming concave portion in the rotation direction on the outer peripheral surface in the shape of the lower layer absorbent body 10 being continuous in the longitudinal direction. A rotating drum is provided. Similarly, in the fiber stacking apparatus that manufactures the continuous body 11A of the upper layer absorbent body, the absorbent body forming concave portion having the shape in which the upper layer absorbent body 11 is continued in the longitudinal direction is continuously formed in the rotation direction on the outer peripheral surface. It is equipped with a spinning drum for stacking fibers. In addition, in a state where the lower layer absorbent continuous body 10A and the upper layer absorbent continuous body 11A are stacked, these are integrally surrounded by a core wrap sheet continuous body, and then the lower layer absorbent continuous body 10A, upper layer It is preferable to integrally cut the continuous body 11A of the absorbent body and the continuous body of the core wrap sheet. As shown in FIG. 1, the leakage of the superabsorbent polymer from the cut portion is caused by the leakage preventing sheet 2 extending outward from the absorbent body 4 at the upper and lower end edges of the absorbent body 4 in the subsequent steps. The outer edge portions of the top sheet 3 and the exterior sheet 5 are prevented from being joined by the joint portion F. Thus, in this pad 1, since the said upper layer absorber 11 is arrange | positioned over the full length of the lower layer absorber 10, in manufacture of the said absorber 4, it forms in the outer peripheral surface of the rotation drum for fiber piles. Absorber forming recesses can be continuously provided in the circumferential direction, and manufacturing of the absorbent body is compared to the case where the lower layer absorbent body and the upper layer absorbent body are individually stacked with a predetermined interval as in the past. Improves efficiency, improves the yield without waste of pulp and polymer deposited at spaced intervals, and eliminates suction unevenness, so the blend of pulp fiber and superabsorbent polymer increases the overall length of the absorber There is an advantage that the same body fluid absorption effect can be obtained up to the end of the absorbent body.

  In the pad 1, the upper layer absorbent body 11 extends along the longitudinal direction and is intermittently arranged over a plurality of strips with a gap in the width direction, and therefore, between the adjacent upper layer absorbent bodies 11, 11. The body fluid easily flows into the lower layer absorbent through the gap 13 formed in the bottom. That is, when the body fluid penetrates into the skin side surface of the upper layer absorbent body 11 arranged on the skin contact surface side of the absorbent body 4, the upper layer absorbent body 11 has a high content ratio of the superabsorbent polymer having a slow absorption speed and absorbs the body fluid. Since the content ratio of the pulp fiber having a high speed is low, the upper body absorbent 11 absorbs a small amount of body fluid, and most of the body fluid overflows the skin side surface of the upper absorbent body 11 and moves to the lower absorbent body 10 through the gap portion 13. . In the lower layer absorbent body 10, the content ratio of the superabsorbent polymer is lower than the content ratio of the superabsorbent polymer in the upper layer absorbent body 11, and the content ratio of the pulp fiber is increased. Due to the action, the body fluid is easily absorbed in the lower layer absorber 10, and the absorbed body fluid is easily diffused in the lower layer absorber 10. For this reason, the absorption speed of a bodily fluid can be increased. In particular, since the gap 13 is provided continuously over the entire length of the lower layer absorbent body 10, even if the excretion position slightly deviates in the front-rear direction due to the wearer's body shape and posture, the mounting position of the pad 1, etc. The body fluid easily moves to the lower layer absorbent body 10 through the gap 13 and the absorption speed can be increased more reliably. The body fluid absorbed by the lower layer absorber 10 is also diffused into the adjacent upper layer absorber 11 and is absorbed and held by the superabsorbent polymer contained in the upper layer absorber 11.

  In addition, by increasing the content ratio of the superabsorbent polymer in the upper layer absorbent body 11 to be higher than the content ratio of the superabsorbent polymer in the lower layer absorbent body 10, the water holding power on the skin contact surface side of the lower layer absorbent body 10 is increased. Therefore, the body fluid absorbed by the lower layer absorbent body 10 can be prevented from returning to the skin side after liquid absorption. That is, when the body fluid absorbed in the lower layer absorbent 10 penetrates into the skin side and passes through the upper layer absorbent 11, it is absorbed and retained by the superabsorbent polymer contained in the upper layer absorbent 11, so that the upper layer absorbent The body fluid does not overflow to the 11th skin side, and reversion can be prevented. Further, the body fluid that has permeated the skin side of the lower layer absorbent body 10 in the portion corresponding to the gap portion 13 does not have the upper layer absorbent body 11 on the skin contact surface side, but the upper layer absorbent body 11 adjacent to the gap portion 13. Therefore, the body fluid does not overflow to the skin side of the upper layer absorbent body 11 through the gap portion 13.

  Further, since the content ratio of the superabsorbent polymer is high in the upper layer absorbent body 11 and the content ratio of the pulp fiber is low, the thickness of the absorbent body 4 is reduced, and the wearing feeling can be improved.

  DESCRIPTION OF SYMBOLS 1 ... Pad, 2 ... Leak-proof sheet, 3 ... Surface sheet, 4 ... Absorber, 5 ... Exterior sheet, 6 ... Side nonwoven fabric, 7 ... Thread-like elastic elastic member, 8 ... Core wrap sheet, 10 ... Lower layer absorber, 11 ... upper layer absorber, 12 ... notch around leg, 13 ... gap

Claims (6)

An absorbent article comprising an absorbent body comprising a lower layer absorbent comprising pulp fibers and a superabsorbent polymer and an upper absorbent comprising a pulp fiber and a superabsorbent polymer disposed on the skin side of the lower absorbent. And
The upper layer absorber extends along the longitudinal direction and is intermittently arranged over a plurality of strips with a gap in the width direction, and the content ratio of the superabsorbent polymer in the upper layer absorber is the lower layer absorber. An absorbent article characterized by having a content ratio higher than that of the superabsorbent polymer.   The content ratio (X) of the superabsorbent polymer in the upper layer absorber is 50 to 90 wt%, the content ratio (Y) of the superabsorbent polymer in the lower layer absorber is 5 to 50 wt%, The absorbent article according to claim 1, wherein the difference (XY) between the content ratio of the superabsorbent polymer in the upper layer absorbent body and the content ratio of the superabsorbent polymer in the lower layer absorbent body is 10 to 85.   The upper layer absorber is disposed over the entire length of the lower layer absorber, and a gap formed between adjacent upper layer absorbers is provided continuously over the entire length of the lower layer absorber. 2. Absorbent article in any one of 2.   The absorptive article according to any one of claims 1 to 3 in which said upper layer absorber is intermittently arranged in two strips at intervals in the center in the width direction of said lower layer absorber. The lower layer absorbent body is formed with a leg notch on the side corresponding to the crotch portion of the wearer,
The said upper layer absorber is arrange | positioned in the width direction inner side from the said leg periphery notch part, and is not arrange | positioned in the both sides of the said lower layer absorber containing the said leg periphery notch part. Absorbent articles. The lower-layer absorbent body is formed with a leg notch on each side of the part corresponding to the crotch of the wearer,
The said upper layer absorber is arrange | positioned separately in the both sides of the said lower layer absorber containing the said leg periphery notch part, respectively by the front side and the rear side of the said leg periphery notch part. Absorbent article as described in 1.

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