JP6990109B2 - Absorbent article - Google Patents

Description

The present invention relates to an absorbent article.

Absorbent articles such as disposable diapers and incontinence pads are provided with a surface sheet on the skin-facing surface side of the absorber that absorbs excrement such as urine. From the viewpoint of easy transfer of excrement liquid to the absorber, an absorbent article in which a recess such as a squeezing groove is formed in the surface sheet has been proposed. For example, Patent Document 1 includes an absorbent layer having a highly absorbent polymer and a squeezed groove, and the region in which the absorbent layer is arranged has a distribution region in which the highly absorbent polymer particles are present and a highly absorbent groove. A body fluid-absorbing article divided into a non-distributed region in which polymer particles do not exist, a squeezed groove is formed in the non-distributed region, and the non-distributed region extends outward from the peripheral edge of the squeezed groove. Is described. Regarding this squeezed groove, it is described that the absorption layer is squeezed, and the squeezing forms a high-density portion extending in the thickness direction, which is denser than the periphery.

The applicant has a first hydrophilicity region in which the surface sheet is composed of continuous lines of a plurality of recesses, and a second hydrophilicity region in which the continuous lines of the first hydrophilicity region intersect with each other, and each of the first hydrophilic regions. We have proposed an absorbent article in which the continuous line of the degree region is widened at the intersection of the continuous lines of a plurality of first hydrophilic regions (Patent Document 2).

Japanese Unexamined Patent Publication No. 2010-066954 Japanese Unexamined Patent Publication No. 2017-11326

On the other hand, from the viewpoint of obtaining a good wearing feeling, it is desired to reduce the thickness of the absorber. However, in the body fluid-absorbing article described in Patent Document 1, if a thin absorber is provided, the portion of the squeezed groove becomes hard due to squeezing, and the hardened portion causes a feeling of discomfort when worn, which is excellent. I can't get a feeling of wearing it. Further, the thinned absorber generally contains a large amount of water-absorbent resin, but in the body fluid-absorbent article described in Patent Document 1, there is a possibility that the absorbent resin contained in the absorbent layer may leak due to squeezing. there were.
The absorbent article described in Patent Document 2 has room for improvement in the diffusivity of the excrement liquid on the surface sheet.

Therefore, an object of the present invention is to provide an absorbent article that can eliminate the drawbacks of the above-mentioned prior art.

The present invention has a vertical direction corresponding to the front-back direction of the wearer and a horizontal direction orthogonal to the vertical direction, and forms a skin facing surface, a back surface sheet forming a non-skin facing surface, and both of these sheets. An absorbent article comprising an intervening absorber, wherein the absorber comprises a substrate sheet and an absorbent core formed on one side of the substrate sheet, wherein the absorbent core absorbs water. The surface sheet contains a sex resin and a water-soluble polymer that fixes the water-absorbent resin to the base sheet, and the surface sheet is formed on both sides of the excretion portion facing portion along the vertical direction, and the skin of the surface sheet. The squeezing groove is formed on the facing surface side or the non-skin facing surface side and has a pair of squeezing grooves extending in the vertical direction, and is on the surface of the surface sheet opposite to the surface on which the squeezing groove is formed. It is intended to provide an absorbent article in which the opposite surface at the site having the above does not protrude from the opposite surface at a site other than the squeeze groove.

Further, the present invention is a method for producing the absorbent article, wherein the absorbent body is interposed between the front surface sheet in which the squeezed groove is formed by embossing and the back surface sheet. It provides a manufacturing method.

The absorbent article of the present invention is thin and has excellent diffusivity of excrement such as urine, and is also excellent in wearing comfort.

FIG. 1 is a plan view of an incontinence pad according to an embodiment of the absorbent article of the present invention. FIG. 2 is a cross-sectional view schematically showing the cross section taken along the line I-I of FIG. 3A is an enlarged cross-sectional view of the front surface sheet, the absorber, and the back surface sheet shown in FIG. 2, and FIG. 3B is an enlarged cross-sectional view of the pressed portion shown in FIG. 3A. FIG. 4 is a corresponding diagram of FIG. 3A in another embodiment of the invention. FIG. 5 is a view corresponding to FIG. 2 of an absorbent article having a surface sheet having a single-layer structure. 6 (a) and 6 (b) are cross-sectional views showing an absorbent article provided with a surface sheet having a squeeze groove formed on a non-skin facing surface side. FIG. 7 is a view corresponding to FIG. 2 of an absorbent article having an absorbent core in which a notch is formed. FIG. 8 is a perspective view showing an apparatus for manufacturing the absorber shown in FIG. FIG. 9 is a perspective view showing an apparatus for manufacturing the absorber shown in FIG. 7.

Hereinafter, the absorbent article of the present invention will be described with reference to the drawings based on the incontinence pad 1, which is a preferred embodiment thereof. FIG. 1 shows a plan view of the incontinence pad 1 of the present embodiment as viewed from the surface sheet 2 side, and FIG. 2 shows a cross-sectional view of the incontinence pad 1 of the present embodiment. As shown in FIG. 2, the incontinence pad 1 of the present embodiment has a liquid-permeable front surface sheet 2 forming a skin facing surface, a back surface sheet 3 forming a non-skin facing surface, and between these two sheets 2 and 3. It comprises an intervening absorber 4.

As shown in FIG. 1, the incontinence pad 1 has an excretion portion facing portion B which is arranged to face the wearer's excretion portion (vaginal opening or the like) at the time of wearing, and the wearer's ventral side (the wearer's ventral side (the wearer's ventral side) with respect to the excretion portion facing portion B. It has a front portion A arranged closer to the front side) and a rear portion C arranged closer to the back side (rear side) of the wearer than the excretion portion facing portion B. The incontinence pad 1 has a vertical direction X corresponding to the front-back direction of the wearer and a horizontal direction Y orthogonal to the vertical direction X, and in the vertical direction X, the front portion A, the excretion portion facing portion B, and the rear portion C. It is divided in order. The vertical direction X corresponding to the front-back direction of the wearer is a direction from the ventral side of the wearer to the dorsal side through the inseam when worn. Further, the incontinence pad 1 is formed symmetrically with respect to the center line CL extending in the vertical direction X. The vertical direction X is also a direction parallel to the center line CL.

Further, in the present specification, the skin facing surface is a surface of the incontinence pad 1 or a component thereof (for example, an absorber 4) that is directed toward the wearer's skin side when the incontinence pad 1 is worn, and the non-skin facing surface is a surface facing the skin. , The surface of the incontinence pad 1 or its constituent members that is directed to the side opposite to the skin side (clothing side) when the incontinence pad 1 is worn.

Further, in the absorbent article of the present invention, the excretory portion facing portion B is an absorbent article having no wing portion such as the incontinence pad 1 of the present embodiment, and the absorbent article is individually packaged in three folds. The vertical direction of the absorbent article with respect to the two folding curves (not shown) that cross the absorbent article laterally (horizontal direction of the absorbent article, Y direction in the figure) that occurs when folded. It means the area surrounded by the first folding curve and the second folding curve counting from the front end of X. In the absorbent article having a wing portion, the excretion portion facing portion B is a region having the wing portion (in one wing portion) in the vertical direction of the absorbent article (longitudinal direction of the absorbent article, X direction in the drawing). It means a region sandwiched between a base along the vertical direction X and a base along the vertical direction X of the other wing portion).

In the incontinence pad 1, as shown in FIGS. 1 and 2, the surface sheet 2 covers the entire surface of the absorber 4 facing the skin, and is outside the lateral direction Y from both side edges along the vertical direction X of the absorber 4. It extends to the direction. On the other hand, the back surface sheet 3 covers the entire non-skin facing surface of the absorber 4, and further extends outward in the lateral direction Y from both side edges along the vertical direction X of the absorber 4, and the side sheet 5 described later. Aside from this, a side flap portion S is formed. An adhesive portion 31 for fixing to underwear such as shorts is provided on the non-skin facing surface on the back surface sheet 3 side of the incontinence pad 1. The back surface sheet 3 and the side sheet 5 are bonded to each other by known bonding means such as an adhesive, a heat seal, and an ultrasonic seal at the extending portions from both side edges of the absorber 4 along the vertical direction X. In addition, each of the front surface sheet 2 and the back surface sheet 3 and the absorber 4 may be bonded by an adhesive.

As the surface sheet 2, for example, a woven fabric made of synthetic fibers or natural fibers, a non-woven fabric, a porous sheet, or the like can be used on the premise that the surface sheet 2 is a liquid permeable sheet capable of permeating body fluids such as urine.
As shown in FIG. 2, the surface sheet 2 of the present embodiment is composed of a composite sheet having a first sheet 2a arranged on the skin facing surface side and a second sheet 2b arranged on the non-skin facing surface side. .. The first sheet 2a and the second sheet 2b are made of a sheet material. As the sheet material, for example, a fiber sheet such as a non-woven fabric, a woven fabric and a knitted fabric, a film or the like can be used, and it is preferable to use a fiber sheet from the viewpoint of touch and the like, and it is particularly preferable to use a non-woven fabric. The types of sheet materials constituting the first sheet 2a and the second sheet 2b may be the same or different.

Examples of the non-woven fabric when the non-woven fabric is used as the sheet material constituting the first sheet 2a and the second sheet 2b include air-through non-woven fabric, spunbond non-woven fabric, spunlace non-woven fabric, melt blown non-woven fabric, resin bond non-woven fabric, needle punch non-woven fabric and the like. Be done. It is also possible to use a laminated body in which two or more kinds of these non-woven fabrics are combined, or a laminated body in which these non-woven fabrics and a film or the like are combined. Among these, it is preferable to use an air-through non-woven fabric or a spunbonded non-woven fabric.

As the fiber constituting the non-woven fabric, a fiber made of various thermoplastic resins can be used. Examples of the thermoplastic resin include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, polyamides such as nylon 6 and nylon 66, polyacrylic acid, polymethacrylic acid alkyl esters, polyvinyl chloride, and polyvinylidene chloride. One of these resins can be used alone or as a blend of two or more. Further, it can be used in the form of a composite fiber such as a core sheath type or a side-by-side type.

As the material for forming the back sheet 3, various materials conventionally used for absorbent articles can be used without particular limitation. For example, a liquid-impermeable or water-repellent resin film, a laminated sheet of a resin film and a non-woven fabric, or the like can be used. With respect to the back surface sheet 3, the liquid impermeability is a concept including the impermeability of the liquid, and includes the case where the back surface sheet 3 does not allow the liquid to pass through at all.

In the incontinence pad 1, as shown in FIGS. 1 and 2, a pair of side seats 5 are arranged on both sides of the skin facing surface along the vertical direction X. Preferably, the side seats 5 are arranged over the entire length of the incontinence pad 1 in the vertical direction X so as to overlap the left and right side portions of the absorber 4 along the vertical direction X in a plan view. The side sheet 5 extends outward in the lateral direction Y from the absorber 4, and the extending portion thereof and the extending portion in the lateral direction Y of the back surface sheet 3 are joined to form a side flap portion S. is doing.

One or a plurality of thread-like elastic members 16a are fixed to the inner edge of the side sheet 5 in the lateral direction Y in an extended state along the vertical direction X, and the incontinence pad is caused by the contraction of the elastic members 16a. A pair of leakage-proof cuffs 15 extending in the vertical direction X are formed on both sides of the vertical direction X of 1. The leak-proof cuff 15 has a fixed end 15b extending in the vertical direction X, a free end 15a extending in the vertical direction X, and a folded-back portion 15c folded outward between the free end 15a and the fixed end 15b. .. The folded portion 15c is folded outward from the bent portion 15d in the lateral direction Y. Further, the leakage-proof cuff 15 has an expansion / contraction portion 16 to which the elastic member 16a described above is fixed on the free end 15a side. The stretchable portion 16 has elasticity in the vertical direction X, and the folded-back portion 15c stands up toward the wearer's body side due to the contraction of the stretchable portion 16. The leak-proof cuff 15 has a fixing portion 5a fixed to the surface sheet 2 by a joining means such as an adhesive in the vicinity of each of both side edges along the longitudinal direction of the absorber 4, and the fixing portion 5a has a lateral Y in the lateral direction. The inner end is the fixed end 15b of the leak-proof cuff 15. The leak-proof cuff 15 is designed to prevent lateral leakage of excretory liquid such as urine by standing between the fixed end 15b and the free end 15a while wearing the cuff 15.
As shown in FIG. 1, the leak-proof cuff 15 is continuous over the entire length of the portion of the incontinence pad 1 having the leak-proof cuff 15 in the vertical direction X, and both ends of the leak-proof cuff 15 in the vertical direction X. The above-mentioned expansion / contraction portion 16 is provided between 15P and 15P. The expansion / contraction portion 16 of the present embodiment is arranged inward in the vertical direction X from both ends 15P and 15P of the leakage-proof cuff 15.

As the side sheet 5, various types conventionally used in the art can be used without particular limitation. For example, a liquid-impermeable or water-repellent nonwoven fabric or resin film, or a laminate of a resin film and a nonwoven fabric can be used. Etc. can be used.

In the incontinence pad 1, the front surface sheet 2 and the back surface sheet 3 extend outward in the vertical direction X from each of the front end and the rear end in the vertical direction X of the absorber 4, and the adhesive and the heat seal are formed at the extending portions. , They are bonded to each other by a known bonding means such as an ultrasonic seal. Specifically, as shown in FIG. 1, the front surface sheet 2 and the back surface sheet 3 are joined by a joining portion (not shown) at the extending portions on the front end side and the rear end side in the vertical direction X.
As shown in FIG. 1, the absorber 4 in the present embodiment has a substantially rectangular shape having convex portions convex toward the outside of the vertical direction X at both ends of the vertical direction X, and has a front portion. It extends from A through the excretion portion facing portion B to the posterior portion C.

As shown in FIG. 2, the absorber 4 of the present embodiment includes a base sheet 20 and an absorbent core 14 formed on one side of the base sheet 20. Since the absorbent core 14 does not contain fiber materials such as pulp fibers, the absorbent body 4 is thinner than the absorbent body having the absorbent core containing pulp fibers.

The absorbent core 14 in the present embodiment includes a water-absorbent resin 43 and a water-soluble polymer 47 that fixes the water-absorbent resin 43 to the base sheet 20 [see FIG. 3A]. In the absorbent core 14, the water-soluble polymer 47 is bonded to the water-absorbent resin 43, and the water-absorbent resin 43 is fixed to the base sheet 20.
As the base material sheet 20, a material capable of holding the absorbent core 14 is used, and it may be a liquid permeable sheet, a liquid impermeable sheet, or a liquid impervious sheet. A laminate of these two or more kinds of materials may be used as a base sheet. From the viewpoint of diffusing excrement such as urine in a plane direction, the base sheet is preferably made of a liquid-permeable fiber sheet.

As the non-woven fabric, those obtained by various manufacturing methods can be used without particular limitation. Examples of the non-woven fabric include spunlace non-woven fabric, spunbond non-woven fabric, air-through non-woven fabric, melt blown non-woven fabric, needle punch non-woven fabric, resin bond non-woven fabric and the like. Each of these non-woven fabrics can be used alone, or can be used in the form of a laminate of two or more kinds of non-woven fabrics.

As the woven fabric, those having various fiber structures can be used. As the paper, those obtained by a wet papermaking method or a dry papermaking method using a papermaking fiber as a raw material can be used. As the film, for example, a film formed by a T-die method or an inflation method and obtained by uniaxial or biaxial stretching can be used.

As the various materials constituting the base sheet 20, for example, synthetic polymer materials such as various thermoplastic resins and natural polymer materials such as cellulose such as pulp can be used. Examples of the thermoplastic resin include polyolefin fibers such as polyethylene (PE) and polypropylene (PP), polyester fibers such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), and polyacrylic acids such as polyacrylic acid and polymethacrylic acid ester. Acid-based fibers, vinyl-based fibers such as polystyrene and polyvinyl chloride can be used. These resins may be used alone or in combination of two or more. When the fibers are formed from these resins, the fibers of a single resin may be formed, or core-sheath type or side-by-side type composite fibers may be formed.

From the viewpoint of shape retention of the absorber 4, the base sheet 20 preferably has a basis weight of 10 g / m ² or more, more preferably 15 g / m ² or more, and 20 g / m ² or more. It is more preferable to have. Further, the base sheet 20 is preferably 70 g / m ² or less, more preferably 65 g / m ² or less, and more preferably 60 g / m ² or less, from the viewpoint of the thinness and flexibility of the absorber 4. Is even more preferable. Specifically, the substrate sheet preferably has a basis weight of 10 g / m ² or more and 70 g / m ² or less, more preferably 15 g / m ² or more and 65 g / m ² or less, and more preferably 20 g / m. It is more preferably ² or more and 60 g / m ² or less.

An absorbent core 14 is formed on one side 20a of the base sheet 20. The absorbent core 14 may be located on the substrate sheet 20 in direct contact with the substrate sheet 20, or one or two or more between the substrate sheet 20 and the absorbent core 14. The base sheet 20 and the absorbent core 14 may be indirectly adjacent to each other in a state where the members and layers of the above are interposed, but from the viewpoint of reducing the thickness of the absorbent article, the base sheet 20 and the absorbent core 14 may be indirectly adjacent to each other. It is preferable that no other member is interposed between 14 and 14.

The absorbent core 14 of the present embodiment contains a water-absorbent resin 43 and a water-soluble polymer 47 that fixes the water-absorbent resin 43 to the base sheet 20. The "water-soluble" of the water-soluble polymer 47 means that the solubility in 100 g of water at 25 ° C. is 0.5 g or more, preferably 1 g or more, more preferably 5 g or more, still more preferably 10 g or more.
The method for confirming whether or not the solubility is 0.5 g or more is as follows. A predetermined amount of the object to be evaluated (water-soluble polymer) and 50 mL of ion-exchanged water having a liquid temperature of 25 ° C. are put into a 100 mL glass beaker (5 mmΦ) and mixed, and the mixture is mixed with a length of 20 mm in the long axis direction. , A stirrer chip with a length (width) of 7 mm in the minor axis direction is inserted, and the mixture is stirred using a magnetic stirrer (for example, HPS-100 manufactured by AS ONE Co., Ltd.) at a rotation speed of 600 rpm, and the entire amount of the evaluation target is stirred. Check if it dissolves in 50 mL of ion-exchanged water within 24 hours of the start. Such a series of operations was performed on a plurality of samples having different total weights of the evaluation objects (the amount charged into the beaker), and the dissolution amount was the largest among the plurality of samples in which the entire amount of the evaluation objects was dissolved. The value twice the total weight of the evaluation target in the sample is defined as the solubility of the evaluation target in 100 g of water at 25 ° C.
As described above, the water-soluble polymer 47 according to the present invention is dissolved by contact with water.
The absorbent core 14 may contain a fiber material such as pulp fiber, but from the viewpoint of facilitating the thinning of the absorbent article, the absorbent core 14 does not contain the fiber material in the absorbent article of the present invention. It is preferably contained.

Examples of the water-soluble polymer 47 include polyvinylpyrrolidone, polyvinyl alcohol, polyvinyl butyral, dextrin, polyethylene oxide, water-soluble nylon and the like, and among these, one or more selected from polyvinylpyrrolidone, polyvinyl butyral and dextrin are used. preferable. The water-soluble polymer 47 may be used alone or in combination of two or more. Further, among the water-soluble polymers, polyvinylpyrrolidone, particularly K-15, K-30, K-60 or K-90, from the viewpoint of fixing the water-soluble and water-absorbent resin 43 to the base sheet 20. It is preferable to use grade polyvinylpyrrolidone.

The water-absorbent resin 43 is made of a material that can swell by contact with water and absorb and retain water.
The water-absorbent resin 43 is preferably one that can absorb and retain 20 times or more of its own weight of water. Further, the water-absorbent resin 43 preferably absorbs and retains 20 times or more, particularly 30 times or more of its own weight if the object is urine, and absorbs 1 or more, preferably 3 times or more of its own weight if it is blood. -Preferably one that can be held. The upper limit of water absorption / retention in the water-absorbent resin 43 is not particularly limited, but 1000 times its own weight can be used as a guideline for the upper limit.

The water-absorbent resin 43 includes, for example, various hydrogel materials, for example, a cross-linked product of a polymer or copolymer of acrylic acid or an alkali metal salt of acrylic acid, a cross-linked product of polyacrylic acid and a salt thereof, and a cross-linked product of a polyacrylic acid salt graft polymer. Cross-linked product of starch or carboxymethylated cellulose, cross-linked product of hydrolysis product of starch-acrylate-grafted copolymer, cross-linked product of vinyl alcohol-acrylate copolymer, cross-linked product of maleic anhydride grafted polyvinyl alcohol. Cross-linked products, cross-linked isobutylene-maleic anhydride copolymers, saponified products of vinyl acetate-acrylic acid ester copolymers and the like can be used.

The shape of the water-absorbent resin 43 is not particularly limited, and may be spherical, lumpy, bale-shaped, amorphous, or fibrous.

As shown in FIG. 1, the surface sheet 2 is formed on both sides of the excretion portion facing portion B along the vertical direction X along the skin facing surface side or the non-skin facing surface side of the surface sheet 2, and is formed in the vertical direction X. It has a pair of squeezing grooves 6 and 6 that extend. The squeezing groove 6 in the present embodiment extends so that the front portion A side and the rear portion C side are curved outward in the lateral direction Y in a plan view. The term "extending in the vertical direction X" as used herein includes not only extending in a straight line in the vertical direction X but also extending in a curved manner, and means that the squeezing groove 6 is long in the vertical direction.

As shown in FIG. 1, the squeezing groove 6 in the present embodiment includes a plurality of squeezing portions 6a arranged at intervals in the vertical direction X. The squeezing portion 6a forming each squeezing groove 6 has a rectangular shape in a plan view, and the inclination of the squeezing portion 6a is constant with respect to the center line CL. The length of these squeezed portions 6a in the horizontal direction Y is gradually shortened as they are arranged outward in the vertical direction X. In addition to the squeezed portions shown in FIG. 1, all of the plurality of squeezed portions 6a may have the same length in the lateral direction Y. Further, the squeezing groove 6 extends in the vertical direction X so as to gradually curve outward in the horizontal direction Y as it goes outward in the vertical direction X. That is, the squeezing groove 6 is arranged so as to gradually move away from the center line CL toward the outside in the vertical direction X. The squeezing groove 6 may be composed of a plurality of squeezing portions 6a as in the present embodiment, or may be composed of continuous groove portions.

The surface sheet 2 has a recess in which the material for forming the surface sheet 2 is squeezed in the squeezing groove 6 and is recessed from one surface side to the other surface side. In the present embodiment, the plurality of squeezed portions 6a have recesses, but the recesses may be continuous in the longitudinal direction of the squeezing groove 6. The other surface of the surface sheet 2, that is, the surface 65 on the side opposite to the surface having the squeezing groove 6, is also referred to as an opposite surface 65. Further, the surface of the bottom portion at the back in the recessed direction of the recess formed in the squeezing groove 6 is also referred to as a bottom surface 63 of the squeezing groove 6, or simply "bottom surface 63". As shown in FIG. 3B, the bottom surface 63 and the side wall 64 that sandwiches or surrounds the bottom surface 63 form the contour of the recess of the squeezing groove 6.

When the recess of the squeezing groove 6 is recessed from the skin facing surface side (one surface) toward the non-skin facing surface side (the other surface), the non-skin facing surface (the other surface) of the surface sheet 2 is opposite. Surface 65 [see FIGS. 3 (a) and 3 (b)]. In this case, the squeezing groove 6 is formed on the skin facing surface of the surface sheet 2. On the contrary, when the recess of the squeezing groove 6 is recessed from the non-skin facing surface side (one surface) toward the skin facing surface side (the other surface), the skin facing surface (the other surface) of the surface sheet. Is the opposite surface 65 [see FIGS. 6 (a) and 6 (b)]. In this case, the squeezing groove 6 is formed on the non-skin facing surface of the surface sheet 2.
The surface sheet 2 has a portion 26 having a squeezing groove 6 and a portion other than the squeezing groove 6 in the plane direction. In both the case where the squeezing groove 6 is formed on the skin facing surface and the case where the squeezing groove 6 is formed on the non-skin facing surface, the portion 26 having the squeezing groove 6 is the same as the squeezing groove 6 in the plan view of the surface sheet 2. The overlapping portion and the portion other than the squeezing groove 6 is a portion that does not overlap with the squeezing groove 6 in the plan view of the surface sheet 2.
The portion 26 having the squeezing groove 6 is the entire area in the thickness direction of the surface sheet 2 of the portion overlapping the squeezing groove 6 in the plan view of the surface sheet 2, and the portion other than the squeezing groove 6 is the portion other than the squeezing groove 6 in the plan view of the surface sheet 2. It is the entire area in the thickness direction of the surface sheet 2 at the portion that does not overlap with the squeezing groove 6. From this, the opposite surface (the surface opposite to the surface on which the squeezing groove is formed) 65 in the surface sheet 2 is also the surface 65a of the portion overlapping the squeezing groove 6 in the thickness direction, that is, the portion having the squeezing groove 6. It has a surface 65a on the opposite side thereof and a surface 65b of a portion that does not overlap with the squeezing groove 6 in the thickness direction, that is, a surface 65b on the opposite side in a portion other than the squeezing groove 6. The opposite surface is the surface of the surface sheet opposite to the surface on which the squeezing groove is formed.
Hereinafter, on the opposite surface 65, the surface 65a of the portion overlapping the squeezing groove 6 in the thickness direction is also referred to as "the surface 65a of the portion having the squeezing groove 6" or simply "the opposite surface 65a of the squeezing groove 6". Further, the "surface 65b of the portion that does not overlap with the squeezing groove 6 in the thickness direction" is also referred to as "a surface 65b at a portion other than the squeezing groove 6" or simply "an opposite surface 65b other than the squeezing groove 6".
In the thickness direction of the surface sheet 2, the portion overlapping the opposite surface 65b other than the pressing groove 6 is a portion where the forming material of the surface sheet 2 is not compressed. When the surface sheet 2 has a laminated structure, the opposite surface 65 is the other of the layer (sheet) farthest from the other surface side, that is, the surface on which the pressing groove 6 (recess) is formed in the thickness direction. The surface, that is, the surface opposite to the side on which the squeezing groove 6 is formed.
In the squeezing groove 6 in the present invention, the surface sheet 2 penetrates in the thickness direction thereof, that is, the bottom surface 63 of the squeezing groove 6 formed on one surface of the surface sheet 2 is the squeezing groove 6 of the surface sheet 2. The squeezing groove 6 existing at a position protruding from the opposite surface 65b beyond the other opposite surface 65b is not included.

In the present embodiment, as shown in FIGS. 3A and 3B, the squeezing groove 6 has a recess recessed from the skin facing surface side to the non-skin facing surface side of the surface sheet 2. Therefore, in the surface sheet 2, the non-skin facing surface is the opposite surface 65. As shown in FIG. 3B, the surface sheet 2 does not have a portion having the squeezing groove 6 protruding from the opposite surface 65b other than the squeezing groove on the opposite surface 65, and specifically, the surface sheet 2 is squeezed. The opposite surface 65a of the groove 6 does not protrude from the opposite surface 65b other than the squeezing groove 6.
Further, the surface sheet 2 of the present embodiment has a two-layer structure as described above, and the pressing groove 6 is formed on the skin facing surface side of the first sheet 2a. As shown in FIG. 3A, the first sheet 2a of the surface sheet 2 has entered the second sheet 2b in the squeezing groove 6. On the other hand, the opposite surface 65a of the squeezing groove does not protrude toward the absorber 4 from the opposite surface 65b (non-skin facing surface) of the second sheet 2b at a portion other than the squeezing groove 6.
The opposite surface 65a of the pressing groove 6 does not have to protrude from the opposite surface 65b other than the pressing groove 6, and as shown in FIG. 4, the opposite surface 65 of the surface sheet 2 (second) in the thickness direction of the surface sheet 2. The non-skin facing surface of the sheet 2b) and the opposite surface 65a of the squeezing groove 6 of the first sheet 2a may be at the same position in the thickness direction.

As will be described later, it is possible to form a sheet in which the opposite surface 65a of the pressing groove 6 does not protrude from the opposite surface 65b other than the pressing groove 6 by the configuration of the processing apparatus for forming the pressing groove on the surface sheet 2. Is. Whether or not the opposite surface 65a of the squeeze groove 6 protrudes from the opposite surface 65b at a portion other than the squeeze groove 6 can be easily confirmed by observing the surface sheet 2 during the production of the incontinence pad. It is also possible to take out the surface sheet 2 from the incontinence pad 1 and check it. The portion other than the squeezing groove 6 is a portion separated from the outer edge of the squeezing groove 6 in the plane direction by 3 mm or more.

Since the absorbent core 14 is configured not to contain pulp fibers, the incontinence pad 1 is thinner than the incontinence pad having an absorbent core containing pulp fibers.
Further, since the absorbent core 14 of the present invention has the absorbent body 4 and the surface sheet 2 having the above-mentioned structure, it has excellent liquid diffusivity. Specifically, since the pair of squeezing grooves 6 and 6 in the surface sheet 2 extend in the vertical direction X, the excrement liquid discharged to the incontinence pad 1 travels through the squeezing groove 6 in the vertical direction X. Spreads well. Such an effect is similarly exhibited when the pressing groove 6 is formed on the non-skin facing surface side of the surface sheet 2 (see FIG. 6). The embodiment shown in FIG. 6 will be described later.
Moreover, the excrement liquid transferred to the absorbent core 14 diffuses well even in the absorbent body 4. That is, when the absorbent core 14 absorbs the excrement liquid, the water-soluble polymer 47 that fills the space between the water-absorbent resins 43 dissolves in the absorbed portion (hereinafter, also referred to as the absorbing portion). When the water-soluble polymer 47 is dissolved, the water-absorbent resin 43 expands and tends to become large, that is, the water absorption by the water-absorbent resin 43 is less likely to be hindered. Further, due to the dissolution of the water-soluble polymer 47, the gap between the water-absorbent resins 43 becomes larger than before the absorption, and the capillary force of the portion where the excrement liquid is absorbed becomes smaller. On the other hand, in the portion of the absorbent core 14 that does not absorb the excrement liquid (hereinafter, also referred to as the non-absorbent portion), the gap between the water-absorbent resins 43 is smaller than that of the absorbent portion, so that the gap between the water-absorbent resins 43 is smaller than that of the absorbent portion. High capillary strength. As a result, a gradient is formed in the capillary force in the absorbent core, and the excrement fluid moves from the one with the lower capillary force to the one with the higher capillary force. As a result, the absorbent core 14 efficiently moves the excrement from the absorbed portion to the non-absorbed portion. Due to the above-mentioned action, the absorbent article of the present invention is excellent in liquid diffusivity, and in particular, it is excellent in diffusivity in the vertical direction X due to the effects of the pressing grooves 6 and 6.
Further, since the opposite surface 65a of the squeezing groove 6 does not protrude from the opposite surface 65b other than the squeezing groove 6, the opposite surface 65a of the squeezing groove 6 protrudes from the opposite surface 65b other than the squeezing groove 6 as compared with the case where the opposite surface 65a protrudes from the opposite surface 65b other than the squeezing groove 6. The contact area between the surface sheet 2 and the absorber 4 is large, and the transferability of the excrement liquid from the surface sheet 2 to the absorber 4 is excellent.

For example, as shown in FIG. 2, when the squeezing groove 6 is formed on the skin facing surface side of the surface sheet 2, the excrement liquid discharged to the incontinence pad 1 travels vertically along the squeezing groove 6 of the surface sheet 2. After diffusing in the direction X, it spreads in the plane direction of the surface sheet 2 through the bottom surface 63 and the side wall 64 (skin facing surface side) of the squeezing groove 6, and the opposite surface 65a of the squeezing groove 6 and the opposite surface other than the squeezing groove 6. It shifts to 65b (non-skin facing surface side) in the thickness direction of the surface sheet 2. After such migration, the excrement fluid rapidly migrates from the opposite surface 65 (non-skin facing surface side) of the surface sheet 2 to the absorber 4 which is in extensive contact with the opposite surface 65.
The effect of liquid diffusion by the squeezing groove 6 is similarly exhibited even when the squeezing groove 6 is formed on the non-skin facing surface side of the surface sheet 2. For example, even in the incontinence pad shown in FIGS. 6 (a) and 6 (b), the excrement liquid is transferred to the squeezing groove 6 via the opposite surface 65a (skin facing surface side) of the squeezing groove 6 in the surface sheet 2. It is diffused in the vertical direction X by the squeezing groove 6. The diffused excrement liquid spreads in the plane direction of the surface sheet 2 through the side wall 64 of the squeezing groove 6 and also shifts to the absorber 4 side in the thickness direction. The excrement liquid thus transferred is rapidly transferred from the surface (non-skin facing surface side) of the surface sheet 2 on the side where the squeezing groove 6 is formed to the absorber 4 in contact with the surface.

The absorbent article of the present invention has a thin thickness, and the liquid easily spreads in the plane direction. If the liquid spreads in the lateral direction, lateral leakage may occur. However, as described above, the absorbent article of the present invention has excellent liquid diffusibility in the vertical direction X. In addition, as described above, the excellent transferability of the liquid from the surface sheet 2 to the absorber 4 utilizes the wide range of absorption capacity of the absorber 4, and lateral leakage is effective despite its thinness. Is suppressed.

Moreover, since the squeezing groove 6 is formed only on the surface sheet, the squeezing portion is not formed on the absorber 4. As a result, the rigidity of the absorber 4 does not change due to squeezing, and the absorber 4 has an excellent wearing feeling when worn.
Further, since the water-absorbent resin 43 is fixed by the water-soluble polymer 47, when the water-soluble polymer 47 is dissolved, the water-absorbent resin 43 becomes fluid. As a result, the thickness of the absorber 4 can be uniformly changed. This also prevents the occurrence of a sense of discomfort due to the local increase in the thickness of the absorber 4 after absorption.

In the surface sheet 2 of the present embodiment, the first sheet 2a and the second sheet 2b are made of a non-woven fabric, and the surface sheet 2 is embossed to be described later to form a pair of squeezing grooves 6 and 6. To. In the bottom surface 63 of the squeezing groove 6 of the present embodiment, the constituent fibers of the non-woven fabric are melted into a film. More specifically, as shown in FIG. 3B, the constituent fibers of the non-woven fabric in a part 67 in the thickness direction of the surface sheet 2 from the bottom surface 63 are formed into a film. On the other hand, the fibers of the surface sheet 2 in the peripheral portion of the squeezing groove 6 and the side wall 64 are not melted [see FIG. 3 (b)]. As a result, a coarse and dense gradient is formed between the peripheral portion of the squeezing groove 6 and the side wall 64 and the bottom surface 63, in which the density of the forming material gradually increases. Therefore, in the squeezing groove 6, a high pulling force for excrement is exerted. As a result, the excrement liquid easily moves to the absorber side of the surface sheet via the squeezing groove 6.
It should be noted that the filmed portion is not only when the entire constituent fibers of the non-woven fabric are filmed in the plane direction (longitudinal direction X, horizontal direction Y) and the thickness direction of the squeezing groove 6, but also a part of the film is formed. Including the case where it is.

The surface sheet 2 of the present embodiment is a composite sheet having a two-layer structure composed of two sheets 2a and 2b, but the surface sheet 2 has a single-layer structure composed of one sheet as shown in FIG. There may be. From the viewpoint of increasing the contact area with the absorber 4, it is preferable that the surface of the surface sheet 2 having a single-layer structure is solid inside the convex portion 12a and the surface facing the absorber 4 is flat.
Even in the surface sheet 2 having a single-layer structure, the opposite surface 65a of the squeezing groove 6 does not protrude from the opposite surface 65b other than the squeezing groove 6. Then, as shown in FIG. 4, the opposite surface 65a of the squeezing groove 6 may be at the same position as the opposite surface 65b other than the squeezing groove 6 in the thickness direction of the surface sheet 2.

The squeezing groove 6 of the present embodiment is formed on the skin facing surface side of the surface sheet 2, but the squeezing groove 6 is a non-skin facing surface of the surface sheet 2 as shown in FIGS. 6A and 6B. It may be formed on the surface side. The squeezing groove 6 shown in FIG. 6A is formed on the non-skin facing surface side of the second sheet 2b of the surface sheet 2. When the squeezing groove 6 is formed on the non-skin facing surface side of the surface sheet 2, when the opposite surface 65a of the squeezing groove 6 protrudes from the opposite surface 65b (the skin facing surface side of the surface sheet 2) other than the squeezing groove 6, the said Excretion may stay between the protruding parts. Further, the protruding portion may come into contact with the wearer's skin to cause a sense of discomfort, and the protruding portion may come into contact with the wearer's skin to deteriorate the touch of the opposite surface 65 of the surface sheet 2. From the viewpoint of preventing these points, as shown in FIGS. 6A and 6B, the squeezing groove 6 is formed on the non-skin facing surface side of the surface sheet 2, and the squeezing groove 6 is formed. It is preferable that the opposite surface 65a does not protrude from the opposite surface 65b (the skin facing surface of the surface sheet 2) other than the pressing groove 6. In the incontinence pad shown in FIGS. 6A and 6B, the opposite surface 65a of the squeezing groove 6 is located on the skin facing surface side in the portion having the squeezing groove 6.
When the surface sheet 2 has an uneven region on the skin facing surface and the opposite surface 65a of the squeezing groove 6 forms a part of the uneven region as in the incontinence pad shown in FIG. 6B, the squeezing groove 6 It is preferable that the opposite surface 65a does not protrude from the opposite surface 65b other than the squeezing groove 6, that is, the top of the convex portion of the uneven region on the skin facing surface. The term "not protruding from the top of the convex portion" as used herein includes the fact that the position is the same as the top of the convex portion in the thickness direction.

The squeezing groove 6 shown in FIGS. 6A and 6B is formed on the non-skin facing surface side of the surface sheet 2. The surface sheet 2 having such a squeezing groove 6 is made of a non-woven fabric, and the constituent fibers of the non-woven fabric are formed into a film on the bottom surface 63 of the squeezing groove 6, and the non-woven fabric is formed on the opposite surface 65a of the squeezing groove 6. It is preferable that the constituent fibers are not formed into a film. With such a configuration, from the opposite surface 65a (skin facing surface side) to the bottom surface 63 (non-skin facing surface side) of the squeezing groove 6, a coarse and dense gradient is formed in which the fiber forming material gradually increases, and a high pull-in is formed in the squeezing groove 6. Power is played. Further, since the skin surface side is not formed into a film, the touch of the surface sheet 2 is kept good. Further, the film formation on the bottom surface 63 can suppress the leakage of the water-absorbent resin 43.

As shown in FIGS. 6A and 6B, when the surface sheet 2 has the pressing groove 6 on the non-skin facing surface side, the surface sheet 2 and the absorber 4 are compared with the case where the pressing groove 6 is not provided. Since the contact area with the surface sheet 2 is reduced, the transferability of the excrement liquid from the surface sheet 2 to the absorber 4 tends to be reduced. On the other hand, the texture of the surface sheet 2 is kept good, and as described above, the diffusivity of the liquid is exhibited in the same manner as when the surface sheet has the pressing groove 6 on the side facing the skin. From the viewpoint of improving such an effect, when the surface sheet 2 has the squeezing groove 6 on the non-skin facing surface side, the width W8 of the squeezing groove 6 [see FIG. 3 (b)] is preferably 5 mm or less, preferably 3 mm or less. More preferred.

The squeezing groove 6 is formed in the excretion portion facing portion B in the incontinence pad 1, but the length L6 of the squeezing groove 6 in the vertical direction X may be longer than the length of the excretion portion facing portion B in the vertical direction X. .. That is, the squeezing groove 6 may extend from the excretion portion facing portion B to the front portion A side, the rear portion C side, or both sides in the vertical direction X.

From the viewpoint of easily diffusing the excrement toward the posterior portion C, the squeezing groove 6 is composed of a plurality of squeezing portions 6a formed at intervals in the vertical direction X, as shown in FIG. The pair of squeezing grooves 6 and 6 have a distance W6 between the pair of squeezing grooves 6 and 6 in the lateral direction Y on the rear portion C side in the vertical direction X as the distance W6 from the central portion in the longitudinal direction of the incontinence pad toward the rear portion C side. It is preferable that it is enlarged. That is, it is preferable that the distance W6 between the squeezing grooves 6 and 6 in the lateral direction Y expands toward the rear portion C side in the portion on the rear portion C side in the vertical direction X. With such a configuration, the excrement liquid that has moved in the vertical direction X along the squeezing groove 6 can be efficiently diffused into the above-mentioned unabsorbed portion between the pair of squeezing grooves 6 and 6. Here, the maximum distance of the distance W6 between the pair of squeezing grooves 6 and 6 is preferably 120% or more, more preferably 140% or more, and preferably 250% with respect to the minimum distance (not shown). Hereinafter, it is more preferably 200% or less, preferably 120% or more and 250% or less, and more preferably 140% or more and 200% or less. Further, the maximum distance of the distance W6 between the pair of squeezing grooves 6 and 6 is preferably 50% or more, more preferably 60% or more with respect to the length W4 (see FIG. 1) of the absorber 4 in the lateral direction. It is preferably 90% or less, more preferably 70% or less, preferably 50% or more and 90% or less, and more preferably 60% or more and 70% or less.
Further, the distance between the squeezed portion 6a of one squeezing groove 6 and the squeezing portion 6a of the other squeezing groove 6 which is axisymmetric with respect to the center line CL is also expanded.

Further, as shown in FIG. 1, the squeezing groove 6 may expand as the distance W6 between the pair of squeezing grooves 6 and 6 in the lateral direction Y increases from the central portion in the longitudinal direction of the incontinence pad toward the front portion A.
The pair of squeezing grooves may have a portion in which the distance W6 between the pair of squeezing grooves is constant in the vertical direction X. That is, each of the pair of squeezing grooves 6 and 6 may have a linear portion along the vertical direction X.

From the viewpoint that the squeezing groove 6 more effectively diffuses the excrement in the vertical direction X, the length L6 in the vertical direction X of the squeezing groove 6 (see FIG. 1) is the length L4 in the vertical direction X of the absorber 4. With respect to (see FIG. 1), it is preferably 25% or more, more preferably 45% or more, preferably 80% or less, more preferably 60% or less, and preferably 25% or more and 80% or less. More preferably, it is 45% or more and 60% or less. When the squeezing groove 6 is not a straight line in a plan view, the length L6 of the squeezing groove 6 in the vertical direction X is the end of the squeezing groove 6 from the end on the frontmost portion A side to the end on the rearmost portion C side in the vertical direction X. It is the length to the part.

In the incontinence pad 1, as shown in FIG. 2, as shown in FIG. 2, the surface of the base sheet 20 on which the absorbent core 14 is not arranged faces the skin-facing surface side, and the surface on which the absorbent core 14 is arranged is not. It is arranged facing the skin facing side. With such a configuration, it is possible to prevent the feeling of the water-absorbent resin 43 from being transmitted to the wearer and causing a sense of discomfort when worn. As described above, it is preferable that the side of the base sheet 20 not provided with the absorbent core 14 faces the surface sheet 2 side of the absorber 4.

As shown in FIG. 3A, the surface sheet 2 of the present embodiment is a composite sheet having a laminated structure of the first sheet 2a and the second sheet 2b, and from the concave portion 12b and the convex portion 12a on the skin facing surface side. It has an uneven region. That is, the surface sheet 2 of the present embodiment has an uneven region on the first sheet 2a. There is a hollow portion 2c between the convex portion 12a of the first sheet 2a and the second sheet 2b, and the concave portion 12b portion of the first sheet 2a is joined to the second sheet 2b. That is, the first sheet 2a and the second sheet 2b are joined to each other in the recess 12b. From the viewpoint of improving cushioning property, breathability, and wearing feeling, the surface sheet 2 is preferably a composite sheet in which two sheets are joined, as shown in FIG.

The surface sheet 2 may have a single-layer structure. Further, as shown in FIG. 5, the surface sheet 2 may have a single-layer structure and may have an uneven region on the skin-facing surface side of the single-layer structure. In the case of the single-layer structure, as described above, from the viewpoint of increasing the contact area with the absorber 4, the inside of the convex portion 12a is solid and the surface facing the absorber 4 is flat. preferable.

In the incontinence pad 1 of the present embodiment, as shown in FIG. 2, the surface sheet 2 and the base sheet 20 of the absorber 4 are adjacent to each other. From the viewpoint of facilitating the transfer of the excrement liquid from the surface sheet 2 to the absorber 4, it is preferable that the skin-facing surface of the absorber 4 is adhered to the non-skin-facing surface of the surface sheet 2. The surface sheet 2 and the absorber 4 can be adhered to each other by applying an adhesive to the skin-facing surface of the absorber 4 or the non-skin-facing surface of the surface sheet 2.

As shown in FIG. 2, in the absorber 4 of the present embodiment, the absorbent core 14 is continuously formed in a plane on one surface of the base sheet 20, and the surface thereof is flat, but the absorbent core 14 is absorbent. The surface of the core 14 does not have to be flat, and the core 14 does not have to be continuously formed in a plane. For example, the absorbent core 14 shown in FIG. 7 has a portion 21 having a concave cross section, and the portion 21 has less material for forming the absorbent core 14 than a portion where the portion 21 is not formed. .. Such a portion having a concave cross section is hereinafter also referred to as a notch portion 21. In the absorbent core 14, instead of the notch 21, a portion (penetration portion) in which the material for forming the absorbent core 14 is not arranged may be formed in the portion. The notch 21 and the penetrating portion each extend in the vertical direction X (not shown). The "cross section" in the cross section is a cross section along the thickness direction of the absorber 4.

It is preferable that the squeezing groove 6 overlaps at least partially with the notch 21 or the penetrating portion of the absorbent core in a plan view. With such a configuration, the influence of the rigidity of the pressed portion can be mitigated. Further, since the amount of the water-absorbent resin 43 in the squeezed portion is smaller than that in the portion other than the squeezed portion, it is possible to prevent the water-absorbent resin 43 from leaking from the absorbent core 14.
The notch 21 and the penetrating portion may have the same or similar plan view shape as the plan view shape of the squeeze groove 6.

The length of the notch 21 extending in the vertical direction X and the length X of the penetrating portion in the vertical direction X is preferably 100% or more, more preferably 110% or more, with respect to the length L6 of the vertical X of the pressing groove 6.
When the notch 21 and the penetrating portion are not straight in a plan view, the length of the notch 21 and the penetrating portion in the vertical direction X is the end of the notch 21 and the penetrating portion on the frontmost portion A side in the vertical direction X. It is the length from the portion to the end on the rearmost portion C side.

From the viewpoint of thinning the incontinence pad and improving the wearing feeling, the thickness D1 of the absorber 4 [see FIG. 3A] is preferably 0.1 mm or more, more preferably 0.3 mm or more, and more preferably. Is 2.5 mm or less, more preferably 2.0 mm or less, still more preferably 1.5 mm or less. The thickness D1 of the absorber 4 is the maximum thickness of the absorber 4 before absorption.
Further, the thickness D3 of the absorbent core 14 before absorption is preferably 50% or more, more preferably 65% or more, and preferably 90% or less, more than the thickness D1 of the absorber 4 before absorption. It is preferably 80% or less, preferably 50% or more and 90% or less, and more preferably 65% or more and 80% or less.

From the viewpoint of sufficiently diffusing the excrement liquid, the depth D5 of the squeezing groove 6 is preferably 50% or more, more preferably 75% or more, and more preferably 75% or more with respect to the thickness D3 of the absorbent core 14 before absorption. Is 200% or less, more preferably 165% or less, preferably 50% or more and 200% or less, and more preferably 75% or more and 165% or less.

From the viewpoint of sufficiently diffusing the excrement liquid, the depth D5 of the squeezing groove 6 is preferably 50% or more, more preferably 70% or more, and preferably 100% or less with respect to the thickness D7 of the surface sheet 2. , More preferably 90% or less, preferably 50% or more and 100% or less, and more preferably 70% or more and 90% or less. The thickness D7 of the surface sheet 2 is the maximum thickness of the surface sheet 2. When the surface sheet 2 is a composite sheet having an uneven region as in the present embodiment, the thickness D7 of the surface sheet 2 is from the top of the convex portion 12a of the first sheet 2a to the non-skin facing surface of the second sheet 2b. Up to [see FIG. 3 (a)].

The thickness D1 of the absorber 4 and the thickness D3 of the absorbent core 14 are measured by the following methods. First, the absorber 4 to be measured is placed on a horizontal place without wrinkles or bending, and the thickness under a load of 5 cN / cm ² is measured. Specifically, for measuring the thickness, for example, a thickness gauge (PEACOCK DIAL UPRIGHT GAUGES R5-C manufactured by Ozaki Seisakusho Co., Ltd.) is used. At this time, a circular or square plate (acrylic plate with a thickness of about 5 mm) whose size is adjusted so that the load is 5 cN / cm ² between the tip of the thickness gauge and the object to be measured. And measure the thickness. By this method, the thickness D1 of the absorber 4 and the thickness of the base sheet 20 are measured, and the difference value thereof is taken as the thickness of the absorbent core 14. Further, the depth D5 of the squeezing groove 6 and the depth of the notch 21 can be measured, for example, by measuring the thickness of each layer by enlarging the cross section by about 20 times with the Keyence digital microscope VHX-900. Be measured.

From the viewpoint of ensuring good absorption of the incontinence pad, the water-absorbent resin 43 has a particle size D50 at a cumulative volume of ₅₀ % measured by a laser diffraction type particle size distribution method, that is, a median diameter of preferably 150 μm. As described above, it is more preferably 180 μm or more, preferably 500 μm or less, more preferably 400 μm or less, and preferably 150 μm or more and 500 μm or less, more preferably 180 μm or more and 400 μm or less.
The median diameter of the water-absorbent resin 43 can be measured under the following measurement conditions using a laser diffraction / scattering type particle size distribution measuring device (LA-920, manufactured by HORIBA, Ltd.).
Measurement method: Flow method Dispersion medium: Ethanol / distilled water = 90/10 wt%
Dispersion method: stirring, built-in ultrasonic wave 3 minutes Sample concentration: 0.1%

Regarding the above-mentioned measurement of the median diameter, the water-absorbent resin 43 can take out the absorbent body 4 from the absorbent article and collect it from the absorbent body 4.
In the present specification, when the constituent member (for example, an absorber) is taken out from the absorbent article and the constituent member is evaluated and measured, the constituent member is fixed to another constituent member by an adhesive, fusion, or the like. If so, the fixed portion is removed by applying a solvent, blowing hot air with a dryer, blowing a cold spray (for example, a commercially available product manufactured by Nichiban Co., Ltd.), and then taking out the fixed portion.

From the viewpoint of maintaining a good fit even after the excrement is absorbed, the ratio of the water-soluble polymer 47 to the water-absorbent resin 43 in the absorbent core 14 is preferably 0.1% or more, more preferably 0.3. % Or more, preferably 5% or less, more preferably 4% or less, preferably 0.1% or more and 5% or less, and more preferably 0.3% or more and 4% or less. The "ratio of the water-soluble polymer 47 to the water-absorbent resin 43" is a ratio calculated using the mass of the water-absorbent resin 43 contained in the absorbent core 14 as the denominator and the mass of the water-soluble polymer 47 as the numerator. That is.
The content of the water-soluble polymer 47 in the absorbent core 14 is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and preferably 10% by mass or less, more preferably 8%. It is contained in an amount of% by mass or less, preferably 0.05% by mass or more and 10% by mass or less, and more preferably 0.1% by mass or more and 8% by mass or less.

The absorbent core 14 may contain other constituent materials other than the water-absorbent resin 43 and the water-soluble polymer 47. For example, it may contain a deodorant, a fragrance, a plasticizer, a polyhydric alcohol and the like.
Further, in addition to the above components, the absorbent core may contain, if necessary, components that can improve various performances of the absorbent core. Examples of such components include thickeners, pH adjusters and the like.

In some absorbent articles, the absorbent core is covered with a core wrap sheet such as tissue paper or non-woven fabric, but from the viewpoint of making the absorbent article thinner, the absorbent core 4 is arranged with the absorbent core. It is preferable that the surface to be covered is not covered with a separate sheet.

The ratio of the absorbent core 14 to the area of the absorber 4 is preferably 50 area% or more, more preferably 60 area% or more, still more preferably 70, from the viewpoint of sufficiently enhancing the absorption capacity and diffusivity of the absorber 4. Area% or more, and 100 area% or less, preferably 95 area% or less, more preferably 90 area% or less, and preferably 50 area% or more and 100 area% or less, more preferably 60 area% or more and 95 area. % Or less, more preferably 70 area% or more and 90 area% or less. The "area of the absorbent body 4" and the "area of the absorbent core 14" are the respective areas on the side surface on which the absorbent core 14 is provided on the base sheet 20. The ratio of the absorbent core 14 to the area of the absorber 4 is 100 area%, which means that the absorbent core 14 is arranged on the entire surface of the base sheet 20.

The above description is for the case where the absorbent core 14 is basically a single layer, but in the present invention, the absorbent core 14 has the same composition or has a different composition. It may have a laminated structure portion having two or more layers.

The absorber 4 according to the present embodiment is formed by applying a composition containing a water-absorbent resin 43 and a water-soluble polymer 47 on one side of a base sheet 20. Hereinafter, the composition containing the water-absorbent resin 43 and the water-soluble polymer 47 is also simply referred to as composition 60. FIG. 8 shows an apparatus 50 suitable for a manufacturing method in which the composition 60 is applied to form an absorbent core 14 to manufacture the absorbent body 4 shown in FIG. The device 50 for manufacturing the absorber 4 shown in FIG. 8 includes a supply unit 51 of the composition 60, a coating unit 53 of the composition 60, and a drying unit 55 of the composition 60.

The supply unit 51 includes a storage tank 51a for the composition 60. The composition 60 is stored in the tank 51a. The composition 60 in the tank 51a is stirred and homogenized by the stirring blade 51b. The stirring blade 51b is connected to a rotary drive source 51d such as a motor via a shaft 51c. One end of the pipeline 52 is connected to the bottom of the tank 51a. The other end of the pipeline 52 is connected to the coating portion 53.

The coating unit 53 includes a coating head 54 for coating the composition 60 on one side of the continuum 20S of the long base sheet 20. Hereinafter, the continuum 20S of the base sheet 20 is also simply referred to as "continuum 20S". The coating head 54 continuously applies the composition 60 supplied from the supply unit 51 via the pipeline 52 along the one-way D, that is, the transport direction D of the continuum 20S. Specifically, the coating head 54 applies the composition 60 in a plane in the region between the side portions 20b and 20b of the continuous body 20S to form the coated body 68 in a wet state. As such a coating head 54, one capable of coating a fluid such as the composition 60 is used. Examples of such a coating head 54 include, but are not limited to, a die coater.

In the transport direction D of the continuum 20S, the drying portion 55 is arranged downstream of the coating portion 53. The drying portion 55 dries the coating body 68 formed by the coating portion 53 to remove volatile components, and fixes the absorbent core 14 which is the dried body of the coating body 68 to the continuous body 20S (base sheet 20). .. The drying portion 55 is a device capable of removing volatile components from the coated body 68 in a wet state, and examples thereof include, but are not limited to, an infrared radiating device and a heated hot air blowing device. ..

The device 50 described above provides a continuum 4S of the absorber 4 having an absorbent core 14 formed on one side of the continuum 20S, that is, one side of the base sheet 20. The continuum 4S of the absorber 4 is subjected to post-processing as necessary. As post-processing, for example, a step of cutting the continuum 4S of the absorber 4 over its longitudinal direction and processing it into the absorber 4 of each leaf, or using the continuum 4S of the absorber 4 as a final product such as an absorbent article. Examples thereof include a step of assembling and a step of winding the continuum 4S of the absorber 4 and converting it into a raw material.

According to the above method, the target absorbent core 14 and absorber 4 can be obtained by a simple process of applying the composition 60 to one side of the base sheet 20 and drying it. Further, according to the above method, the thickness and the basis weight of the absorbent core 14 can be controlled with high accuracy. As a result, it is possible to prevent local variations in the basis weight and thickness of the absorbent core 14, and the absorber 4 can exhibit stable absorption performance. Further, the basis weight of the absorbent core can be arbitrarily changed in a wide area on the base sheet 20. Further, it is also possible to form the absorbent core 14 extremely thinly by applying the composition 60 thinly.

From the viewpoint of further enhancing the above effects, the composition 60 is obtained by dispersing or dissolving the constituent materials of the absorbent core 14 such as the above-mentioned water-absorbent resin 43 and the water-soluble polymer 47 in a solvent. It is preferable to have. The composition 60 may contain water to the extent that the water-absorbent resin 43 does not swell, but the composition 60 may not contain water from the viewpoint of preventing the water-absorbent resin 43 from absorbing water and swelling. preferable. The term "water-free" means that intentionally adding a significant amount of water to the composition 60 is excluded. Therefore, the presence of a small amount of water that is inevitably mixed as an impurity in raw materials and a small amount of water that is inevitably mixed from the atmosphere is allowed.

The ratio of the constituent materials such as the water-absorbent resin 43 and the water-soluble polymer 47 contained in the composition 60 is adjusted so that the water-absorbent resin 43 and the water-soluble polymer 47 in the absorbent core 14 have a desired ratio. .. Further, the composition 60 preferably does not contain a fiber material such as pulp fiber.

As the solvent contained in the composition 60, a non-aqueous solvent is preferably used. Examples of such a non-aqueous solvent include ethanol, methanol, isopropyl alcohol, acetone, methyl ethyl ketone, butyl acetate and the like. These non-aqueous solvents may be used alone or in combination of two or more. Of these non-aqueous solvents, ethanol is preferably used from the viewpoint of availability, versatility, and safety.

The ratio of the non-aqueous solvent to the composition 60 is preferably 30% by mass or more, more preferably 35% by mass or more, still more preferably 40% by mass or more, from the viewpoint of facilitating the coating of the composition 60. Further, it is preferably 70% by mass or less, more preferably 65% by mass or less, further preferably 60% by mass or less, and preferably 30% by mass or more and 70% by mass or less, more preferably 35% by mass or more and 65% by mass or less. More preferably, it is 40% by mass or more and 60% by mass or less.

From the viewpoint of providing the above-mentioned penetration portion in the absorbent core 14, the coating head 54 coats the composition 60 on the base sheet 20 so as to partially form the non-coated portion of the composition 60. The coated body 68 may be formed. After the coated body 68 is dried, the non-coated portion becomes a penetrating portion.

Further, the absorbent core 14 having the notch 21 described above can be formed by a device 50A in which the coating portion 53 has two or more coating heads 54, as shown in FIG. 9, for example. The coating portion 53A included in the device 50A has two coating heads, a first coating head 54a and a second coating head 54b. These coating heads 54a and 54b are arranged in series along the transport direction D of the base sheet 20, the first coating head 54a is located on the upstream side of the transport direction D, and the first coating head 54a is located on the downstream side of the transport direction D. Two coating heads 54b are arranged. The first coating head 54a applies the composition 60 to the region between the side portions 20b and 20b of the continuous body 20S to form the first coating body 68A in a wet state. On the other hand, as shown in FIG. 9, the second coating head 54c has the second coating body 68B in a wet state on the first coating body 68A so as to partially have the non-coated portion 68C extending in the transport direction D. Form. The non-coated portion 68C formed by the second coating head 54b becomes a concave notched portion 21 after drying. The composition 60 used to form the first coating body 68A and the composition 60 used to form the second coating body 13B may have different compositions or are the same. May be there.
Further, the composition 60 may be discharged so as to form the notch 21 with one coating head 54.

The apparatus 50 has an absorption structure having a laminated structure in which two or more layers are laminated by a coating portion 53A having two coating heads 54a and 54b or a coating portion 53 having a plurality of coating heads 54. The sex core 14 can be formed.

In the conventional absorbent article, in a state where the absorber and the surface sheet are overlapped, embossing is performed from the surface sheet side to form a squeeze groove in the surface sheet.
On the other hand, the incontinence pad 1 of the present embodiment is manufactured by interposing the absorber 4 manufactured as described above between the front surface sheet 2 in which the pressing groove 6 is formed by embossing and the back surface sheet 3. To.

For example, by sandwiching the surface sheet 2 between the embossed convex rolls and the flat rolls arranged so as to face each other and pressing the surface sheet 2, the pressing groove 6 can be formed intermittently or continuously in the surface sheet 2. The opposite surface 65a of the squeezing groove 6 formed by such a method does not protrude from the opposite surface 65b other than the squeezing groove 6.

Although the present invention has been described above, the present invention is not limited to the above-described embodiment and can be appropriately modified without departing from the spirit of the present invention.
For example, the absorbent article of the present invention may be a disposable diaper, a sanitary napkin, or the like, in addition to the incontinence pad.

1 Incontinence pad 2 Front sheet 3 Back sheet 4 Absorber 5 Side sheet 6 Squeezing groove 20 Base sheet 20S Continuum 14 Absorbent core 43 Water-absorbent resin 47 Water-soluble polymer 50 Equipment 51 Supply section 51a Tank 51b Stirring blade 51c Shaft 51d Rotational drive source 52 Pipe line 53 Coating part 54 Coating head 55 Drying part 60 Composition 63 Bottom surface 65 Opposite surface 68 Coating body

Claims (11)

It has a vertical direction corresponding to the front-back direction of the wearer and a horizontal direction orthogonal to the vertical direction, and is interposed between a front surface sheet forming a skin facing surface, a back surface sheet forming a non-skin facing surface, and both sheets. An absorbent article with an orthogonal body
The absorbent body includes a base material sheet and an absorbent core formed on one side of the base material sheet, and the absorbent core fixes a water-absorbent resin and the water-absorbent resin to the base material sheet. Contains water-soluble polymers and
The surface sheet has a pair of squeezing grooves formed on the skin-facing surface side or the non-skin-facing surface side of the surface sheet and extending in the vertical direction on both sides of the excretion portion facing portion along the vertical direction. On the surface of the surface sheet opposite to the surface on which the squeezing groove is formed, the opposite surface of the portion having the squeezing groove protrudes from the opposite surface of the portion other than the squeezing groove. No ,
The absorbent article is formed symmetrically with respect to the center line extending in the vertical direction.
The squeezing groove is composed of a plurality of squeezing portions formed at intervals in the vertical direction.
An absorbent article in which the inclinations of the plurality of squeezed portions with respect to the center line are constant . The absorbent article according to claim 1, wherein the surface sheet has an uneven region composed of concave portions and convex portions on the side facing the skin, and the inside of the convex portions is solid. It has a vertical direction corresponding to the front-back direction of the wearer and a horizontal direction orthogonal to the vertical direction, and is interposed between a front surface sheet forming a skin facing surface, a back surface sheet forming a non-skin facing surface, and both sheets. An absorbent article with an orthogonal body
The absorbent body includes a base material sheet and an absorbent core formed on one side of the base material sheet, and the absorbent core fixes a water-absorbent resin and the water-absorbent resin to the base material sheet. Contains water-soluble polymers and
The surface sheet has a pair of squeezing grooves formed on the skin-facing surface side or the non-skin-facing surface side of the surface sheet and extending in the vertical direction on both sides of the excretion portion facing portion along the vertical direction. On the surface of the surface sheet opposite to the surface on which the squeezing groove is formed, the opposite surface of the portion having the squeezing groove protrudes from the opposite surface of the portion other than the squeezing groove. No,
The surface sheet is a composite sheet to which the first sheet and the second sheet are joined, and the first sheet has an uneven region composed of concave portions and convex portions.
There is a hollow portion between the convex portion of the first sheet and the second sheet.
The first sheet and the second sheet are absorbent articles bonded to each other in the recess. The absorbent article according to any one of claims 1 to 3, wherein the surface sheet is made of a non-woven fabric, and the constituent fibers of the non-woven fabric are formed into a film on the bottom surface of the squeezing groove. The absorbent article according to any one of claims 1 to 4 , wherein the squeezing groove is formed on the non-skin facing surface side of the surface sheet. The absorbent article has a front portion arranged closer to the wearer's ventral side than the excretion portion facing portion and a rear portion arranged closer to the wearer's dorsal side than the excretion portion facing portion. ,
Any one of claims 1 to 5 , wherein the pair of the squeezing grooves expands toward the rear portion side in the longitudinal direction and the distance between the squeezing grooves in the lateral direction increases toward the rear portion side. The absorbent article described in the section. Any of claims 1 to 6 , wherein the absorber has the absorbent core on only one side of the base sheet, and the side of the base sheet that does not have the absorbent core faces the surface sheet side. The absorbent article according to item 1. The absorbent article according to any one of claims 1 to 7 , wherein the skin-facing surface of the absorber is adhered to the non-skin-facing surface of the surface sheet. The absorbent core is formed with a notch having a concave cross-sectional view and having a small amount of the material for forming the absorbent core or a penetrating portion having no material for forming the absorbent core. The penetrating portion extends in the vertical direction and extends in the vertical direction.
The absorbent article according to any one of claims 1 to 8 , wherein the squeezing groove at least partially overlaps the notch or the penetrating portion. The absorbent article according to any one of claims 1 to 9 , wherein the thickness of the absorber is 2.5 mm or less. The method for producing an absorbent article according to any one of claims 1 to 10 .
A method for producing an absorbent article, in which the absorbent body is interposed between the front surface sheet in which the squeezing groove is formed by embossing and the back surface sheet.

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