JP7388868B2 - absorbent articles - Google Patents

Description

The present invention relates to absorbent articles such as disposable diapers.

Absorbent articles such as disposable diapers generally have a top sheet placed relatively close to the wearer's skin, a back sheet placed relatively far from the wearer's skin, and a gap between the two sheets. and an absorber interposed between the two. An absorbent body typically includes an absorbent core mainly made of a water-absorbing material such as wood pulp, and a core wrap sheet that covers the outer surface of the absorbent core. BACKGROUND ART Conventionally, it has been known to subject absorbents to compression processing for the purpose of improving liquid dispersibility, fit, etc. (Patent Documents 1 to 3).

In the absorbent article described in Patent Document 1, a compressed region subjected to compression processing is provided on the non-skin-facing surface side of the absorbent body, and a region facing the compressed region on the skin-facing surface side of the absorbent body is provided. A plurality of compression grooves formed by compression processing are provided in the. According to the absorbent article described in Patent Document 1, diffusion is promoted more on the non-skin-facing surface side of the absorber than on the skin-facing surface side, and the wet area on the skin-facing surface side can be reduced.

In the absorbent article described in Patent Document 2, in the central region of the topsheet, the topsheet and the skin-side core wrap sheet that covers the skin-facing surface of the absorbent core are penetrated in the thickness direction to form inside the absorbent core. A non-skin-side core wrap sheet that covers the non-skin-facing surface of the absorbent core is compressed toward the skin-side core wrap sheet, and a non-skin-side core wrap sheet is provided on the non-skin-facing surface side of the absorbent core. A formed squeezing recess is provided. According to the absorbent article described in Patent Document 2, the pore size of the openings is smaller than the particle size of the water-absorbing polymer contained in the absorbent core when it is saturated with water. It is said that it can prevent the leakage of

In the absorbent article described in Patent Document 3, groove-shaped compressed portions in which the top sheet and the absorbent core are compressed are formed in a lattice shape on the skin-facing surface of the absorbent article, and the absorbent core is A slit portion (following portion) passing through the compressed portion in the thickness direction is provided so as to extend across the compressed portion in plan view. According to the absorbent article described in Patent Document 3, it is said that the comfort of the wearer can be improved.

Japanese Patent Application Publication No. 2011-177306 Japanese Patent Application Publication No. 2015-186511 JP 2018-110853 Publication

Although the absorbent articles described in Patent Documents 1 to 3 have improved liquid dispersibility through the compression process applied to the absorbent body, the liquid permeability in the thickness direction is insufficient, and the surface sheet etc. Since excrement such as urine tends to remain on members that can come into contact with the skin, there is a problem that the skin becomes sticky. In addition, when wearing an absorbent article, liquid that has been absorbed into the absorbent body may migrate to the top sheet side due to the influence of the wearer's body pressure, so-called liquid return. There was also the problem that the liquid that had migrated to the sides would adhere to the wearer's skin.

Therefore, an object of the present invention is to provide an absorbent article in which the skin becomes less sticky due to bodily fluids excreted by the wearer.

The present invention has a vertical direction extending from the ventral side of the wearer through the crotch area to the back side, and a horizontal direction perpendicular to the vertical direction, and includes a crotch area disposed in the groin area and a crotch area extending from the crotch area. The absorbent body is divided into a ventral part disposed on the ventral side of the wearer and a dorsal part disposed on the dorsal side of the wearer from the crotch area, and extends in the longitudinal direction through the crotch area. An absorbent article comprising: a top sheet disposed on the skin-facing side of the absorbent body; and a back sheet disposed on the non-skin-facing side of the absorbent body.
In one embodiment of the absorbent article of the present invention, the absorbent core includes an absorbent core that absorbs and retains body fluids, a skin-side core wrap sheet that covers the skin-facing surface of the absorbent core, and a skin-side core wrap sheet that covers the skin-facing surface of the absorbent core. and a non-skin side core wrap sheet that covers the non-skin facing surface of the skin.
In one embodiment of the absorbent article of the present invention, the absorbent core is formed with a slit portion that penetrates the absorbent core in the thickness direction and extends in the longitudinal direction.
In one embodiment of the absorbent article of the present invention, a fused portion in which the skin side core wrap sheet and the non-skin side core wrap sheet are fused is present in the slit portion.
In one embodiment of the absorbent article of the present invention, the fused portion is located closer to the non-skin facing surface of the absorbent core than the center in the thickness direction of the absorbent core.
In one embodiment of the absorbent article of the present invention, the top sheet and the skin-side core wrap sheet are not joined in a region overlapping the slit portion in plan view, and the back sheet and the non-skin wrap sheet are It is joined to the side core wrap sheet.
In one embodiment of the absorbent article of the present invention, a non-skin side recessed portion in which the non-skin side core wrap sheet and the absorbent core are integrally recessed is formed on the non-skin facing surface of the absorbent body. There is.
Other features, advantages and embodiments of the invention are described below.

According to the present invention, an absorbent article is provided in which the stickiness of the skin due to bodily fluids excreted by the wearer is reduced, and the members that come into contact with the wearer's skin after excreting the bodily fluids have an excellent dry feeling.

FIG. 1 is a developed plan view schematically showing the skin-facing surface side (topsheet side) of a deployable disposable diaper, which is an embodiment of the absorbent article of the present invention, in an expanded and stretched state. In addition, the term "unfolded and stretched state" as used herein means that the diaper is in the unfolded state as shown in Fig. 1, and the diaper in the unfolded state is expanded to the designed dimensions (all effects of the elastic members are excluded). The state in which it is expanded until it becomes the same size as when it is expanded flat. FIG. 2 is a cross-sectional view schematically showing a cross section taken along the line II in FIG. 1 (a cross section taken in the transverse direction along the thickness direction). FIG. 3 is a plan view schematically showing the skin-facing side of the absorber in the diaper shown in FIG. 1. FIG. 4 is a cross-sectional view schematically showing the main parts of FIG. 2 (top sheet, absorbent body, and back sheet) and the adhesive placed between each member. FIG. 5 is a plan view schematically showing an example of the slit section according to the present invention. FIG. 6 is a view corresponding to FIG. 3 of another embodiment of the absorber according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on preferred embodiments thereof with reference to the drawings. In addition, in the description of the following drawings, the same or similar parts are given the same or similar symbols. The drawings are basically schematic, and the ratio of each dimension may differ from the actual one.

The absorbent article (diaper 1) has a longitudinal direction (X) corresponding to the front-back direction of the wearer, that is, a direction extending from the ventral side to the back side through the crotch, and a lateral direction perpendicular to the longitudinal direction (X). (Y). In the following description, unless otherwise specified, the longitudinal direction (X) is a direction along the longitudinal direction (X) of the absorbent article or the longitudinal direction (X) of its constituent members (e.g. absorbent body), and the transverse direction ( X) is a direction along the lateral direction (X) of the absorbent article or the lateral direction (X) of its constituent members.
The absorbent article (diaper 1) includes a crotch area (B) that is placed in the crotch area of the wearer and includes an excretory part facing part (not shown) that faces an excretory part such as the wearer's penis; The ventral part (A) is located on the ventral side (front side) of the wearer compared to (B), and the dorsal part ( C).
1 and 2 show a disposable diaper 1 which is an embodiment of the absorbent article of the present invention, and the diaper 1 has the above-described configuration.

The diaper 1 is a so-called deployable disposable diaper, and fastening members 8 having fastening parts 7 are provided on both side edges along the longitudinal direction A fastening area 9 to which the fastening part 7 can be fastened is provided on the non-skin facing surface of A.

The diaper 1 includes an absorbent body 10 extending in the longitudinal direction X through the crotch area B, a top sheet 3 disposed on the skin-facing side of the absorbent body 10, and a top sheet 3 disposed on the non-skin-facing side of the absorbent body 10. The back sheet 4 is provided with a The absorbent body 10 absorbs and retains body fluids such as urine excreted by the wearer of the diaper 1. In this embodiment, the diaper 1 includes an absorbent body 2 including an absorbent body 10, a topsheet 3, and a backsheet 4, and a flap portion 5 extending outward from the periphery of the absorbent body 2. .

As used herein, "skin-facing surface" refers to the surface of an absorbent article or its constituent members (e.g. absorbent body) that faces the wearer's skin when the absorbent article is worn, that is, the surface facing the wearer's skin relative to the wearer's skin. The "non-skin-facing surface" refers to the surface of the absorbent article or its constituent members that faces away from the skin when the absorbent article is worn, i.e., the side that is relatively far from the wearer's skin. It's on the side. Note that "when worn" here means a state in which the normal proper wearing position, that is, the correct wearing position of the absorbent article is maintained. In FIGS. 2 and 4 (cross-sectional views along the thickness direction) of the present application, the upper surface (relatively upper surface) of each component (for example, the absorber 10) is the skin-facing surface, and the lower surface (relatively lower surface) ) is the non-skin facing surface.

The absorbent main body 2 includes a liquid-permeable top sheet 3 forming a skin-facing surface, a liquid-impermeable, slightly liquid-permeable, or water-repellent back sheet 4 forming a non-skin-facing surface, and both sheets 3, 4. It has a liquid-retaining absorbent body 10 interposed therebetween, and these are integrated by known bonding means such as adhesive. The absorbent main body 2 extends in the longitudinal direction X from the ventral side part A to the dorsal side part C. As the top sheet 3 and the back sheet 4, those conventionally used for this type of absorbent article can be used without particular limitation. As the topsheet 3, for example, various nonwoven fabrics and perforated films can be used. As the back sheet 4, for example, a resin film or a laminate of a resin film and a nonwoven fabric can be used.

The flap portion 5 is constituted by a member extending outward from the periphery of the absorbent main body 2, and is a non-disposed portion of the absorbent body 10. In this embodiment, as shown in FIG. 2, the topsheet 3 covers the entire skin-facing surface of the absorbent core 10, and the backsheet 4 covers the entire non-skin-facing surface of the absorbent core 10, and both The sheets 3 and 4 further extend outward in the horizontal direction Y from both side edges of the absorbent body 2 along the longitudinal direction 2 and side flaps extending outward in the lateral direction Y from the imaginary extension lines of the both side edges are formed. The plurality of members constituting the flap portion 5 are joined to each other by known joining means such as adhesive, heat sealing, and ultrasonic sealing.

As shown in FIGS. 1 and 2, leak-proof cuffs 6 that stand up toward the skin of the wearer when worn are arranged along both sides of the absorbent main body 2 in the longitudinal direction X. More specifically, a pair of liquid-resistant or water-repellent and breathable leak-proof cuff forming sheets 60 are provided on both sides of the skin-facing surface of the absorbent main body 2 along the longitudinal direction X. Leak-proof cuffs 6, 6 are arranged. These pair of leak-proof cuff forming sheets 60, 60 are each fixed at one end side in the lateral direction Y to another member (the top sheet 3 and the back sheet 4 in the illustrated form), The other end is a free end that is not fixed to another member, and a thread-like or band-like elastic member 61 for forming a leak-proof cuff is arranged at the free end so as to be expandable and retractable in the longitudinal direction X. When the diaper 1 is worn, the contractile force of the elastic member 61 for forming a leak-proof cuff causes the free end side of the sheet 60 for forming a leak-proof cuff, at least in the crotch area B, to raise the fixing part 62 with other members to the proximal end. The leak-proof cuff 6 stands up on the wearer's side, and by standing up the leak-proof cuff 6, the leakage of urine and other excreta to the outside in the lateral direction Y is prevented.

A plurality of thread-like or band-like elastic members 51 for forming waist gathers are arranged in the flap part 5 at the end of the longitudinal direction X, that is, the waist end of each of the abdominal part A and the dorsal part C, so that they can be expanded and contracted in the lateral direction Y. The plurality of elastic members 51 are arranged intermittently in the longitudinal direction X at predetermined intervals. The waist end portion is bonded to the sheets constituting the waist end portion (the top sheet 3 and the back sheet 4 in this embodiment) using a bonding means such as an adhesive, with the elastic member 51 stretched in the lateral direction Y. After that, the elastic member 51 is released from the stretched state. When the diaper 1 is worn, the contraction of the elastic member 51 forms a substantially continuous annular waist gather around the entire circumference of the waist end. Further, in the leg portions of the flap portion 5 that are arranged around the wearer's legs when wearing the diaper 1, a leg gather forming elastic member 52 that is stretchable in the vertical direction It extends in the longitudinal direction X over the entire length of. The leg portion is formed by bonding means such as adhesive to the sheets constituting the leg portion (in this embodiment, the leak-proof cuff forming sheet 60 and the back sheet 4) with the elastic member 52 stretched in the longitudinal direction X. After joining, the elastic member 52 is released from the stretched state. When the diaper 1 is worn, leg gathers are formed in the leg portions due to contraction of the elastic member 52.

As shown in FIGS. 3 and 4, the absorbent core 10 includes an absorbent core 11 that absorbs and retains body fluids, a skin-side core wrap sheet 12 that covers the skin-facing surface of the absorbent core 11, and the absorbent core. and a non-skin side core wrap sheet 13 that covers the non-skin facing surface of 11. In the present embodiment, the absorbent core 11 has an hourglass shape in which the central part in the vertical direction X located in the crotch area B is constricted, and has a long shape in the vertical direction X, in a plan view as shown in FIG. There is.

The absorbent core 11 is a main component of the absorbent core 10, and includes a water-absorbing material. Examples of the water-absorbing material include water-absorbing fibers and water-absorbing polymers, and one type thereof can be used alone or two or more types can be used in combination. The absorbent core 11 is typically made of a fiber aggregate containing water-absorbing fibers, or has a form in which particulate water-absorbing polymer is held in the fiber aggregate.

Examples of water-absorbing fibers include wood pulps such as softwood pulp and hardwood pulp, natural fibers such as non-wood pulps such as cotton pulp and hemp pulp; modified pulps such as cationized pulp and mercerized pulp (including cellulose fibers); ); hydrophilic synthetic fibers and the like, and one type of these can be used alone or two or more types can be used in combination. The water absorbent fibers contained in the absorbent core 11 are typically cellulose fibers.

As the water-absorbing polymer, a particulate material is generally used, but a fibrous material may also be used. The shape of the particulate water-absorbing polymer is not particularly limited, and may be, for example, spherical, lump-like, bale-like, or irregularly shaped. The water-absorbing polymer is typically mainly composed of a polymer or copolymer of acrylic acid or an alkali metal salt of acrylic acid. Examples include polyacrylic acid and its salts, polymethacrylic acid and its salts, and specifically, acrylic acid polymers such as Aqualic CA and Aqualic CAW (both manufactured by Nippon Shokubai Co., Ltd.). Partial sodium salts may be mentioned.

The skin side core wrap sheet 12 and the non-skin side core wrap sheet 13 are each made of a sheet mainly composed of fibers, and specific examples thereof include nonwoven fabric and paper. In general, nonwoven fabrics have a higher elongation at break than paper, and are therefore less likely to tear even if the absorbent core 11 is deformed, so nonwoven fabrics are preferred as both core wrap sheets 12 and 13. The nonwoven fabrics constituting both core wrap sheets 12 and 13 are preferably water permeable, such as air-through nonwoven fabrics, heat roll nonwoven fabrics, spunlace nonwoven fabrics, spunbond nonwoven fabrics, meltblown nonwoven fabrics, and spunbond-meltblown-spunbond ( SMS) non-woven fabrics. These nonwoven fabrics may be hydrophilic nonwoven fabrics made of fibers that have been subjected to hydrophilic treatment.

Both core wrap sheets 12 and 13 may be 1) one continuous sheet, or 2) may be separate sheets. In the case of 1), for example, one continuous core wrap sheet having a width of at least two times and at most three times the length of the absorbent core 11 in the lateral direction Y can be used. In the case of 2) above, the skin side core wrap sheet 12 and the non-skin side core wrap sheet 13 may be the same or different in material (type of nonwoven fabric), basis weight, size in plan view, etc. good.

In this embodiment, the above-mentioned 1) is adopted as the form of both core wrap sheets 12 and 13. Specifically, as shown in FIG. 4, one core wrap sheet covers the entire skin-facing surface of the absorbent core 11, and extends from both side edges of the absorbent core 11 in the longitudinal direction X to the lateral direction Y. The extending portion thereof is wound down below the absorbent core 11 to cover the entire area of the non-skin facing surface of the absorbent core 11 . In this single core wrap sheet, the part that covers the skin-facing surface of the absorbent core 11 is the skin-side core wrap sheet 12, and the part that covers the non-skin-facing surface of the absorbent core 11 is the non-skin-side core wrap sheet 13. It is.

In this embodiment in which the above 1) is adopted, as shown in FIG. On the other hand, on the non-skin facing side of the absorbent core 11, there are two fibrous layers (typically non-woven fabric layers) made of the non-skin side core wrap sheet 13. In FIG. 4, a portion indicated by the reference numeral 130 is a portion where two fiber layers made of the non-skin side core wrap sheet 13 are present (hereinafter also referred to as a “two-layer portion”).

As shown in FIG. 4, in the lateral direction Y, the two-layer portion 130 is one of a plurality of (two in the illustrated form) slit portions 15, which will be described later, and which are arranged intermittently in the lateral direction Y. It extends from a position overlapping with the outermost one on the side in plan view to a position overlapping with the outermost one on the other side in the horizontal direction Y, and in the longitudinal direction It extends over the entire length of the core 11 in the longitudinal direction X. The non-skin side core wrap sheets 13 constituting the two-layer portion 130 may be joined to each other via an adhesive.

As shown in FIGS. 1 to 4, the absorbent core 11 is formed with a slit portion 15 that penetrates the absorbent core 11 in the thickness direction and extends in the longitudinal direction X. As shown in FIGS. The slit portion 15 is a groove without a bottom, and is typically a region in which no absorbent core forming material, including a water-absorbing material, is present. However, there may be cases where the absorbent core forming material that has fallen off from the periphery enters the slit section 15, so that the absorbent core forming material is present in the slit section 15. In such a case, the basis weight of the material forming the absorbent core in the slit portion 15 is lower than that in the peripheral portion (for example, an area within 10 mm in the vertical direction X or the horizontal direction Y from the slit portion 15); It is preferably 20% or less, more preferably 10% or less with respect to the basis weight of.

The slit portion 15 contributes to reducing discomfort when wearing the diaper 1 and improving liquid uptake and diffusion. That is, the slit portion 15 functions as a deformation guiding portion (flexible shaft) when the absorbent core 11 equipped with the slit portion deforms by bending in response to an external force such as body pressure, and thereby the absorbent core 10 Deformation that conforms to the wearer's body shape is promoted, and as a result, the discomfort when wearing the diaper 1 is reduced, and the feeling of wearing and fit can be improved. In addition, the slit portion 15 functions as a flow path for excrement such as urine that is to be absorbed by the absorbent body 10, promotes diffusion of the excrement in the surface direction, and contributes to effective utilization of the liquid absorption performance of the absorbent body 10. obtain. Since the slit portion 15 plays such a role, it is preferable that the slit portion 15 be disposed at a portion of the absorbent core 11 that is likely to receive external forces such as body pressure and where excrement is likely to be concentrated. From this point of view, it is preferable that the slit portion 15 be arranged in a portion of the absorbent core 11 located in the crotch region B.

In this embodiment, as shown in FIG. 1, a plurality of slits 15 are arranged intermittently in the lateral direction Y in the crotch area B. More specifically, the slit portion 15 of the present embodiment is symmetrical with respect to a horizontal center line CLy that bisects the unfolded and stretched diaper 1 or absorbent core 11 in the horizontal direction Y and extends in the vertical direction X. , and a pair are formed on both sides of the horizontal center line CLy. The pair of slit portions 15 each have a long shape in the vertical direction X when viewed from above, specifically a rectangular shape. The slit part 15 may extend from the crotch part B to the abdominal part A, or may extend from the crotch part B to the dorsal part C.

The length 15L (see FIG. 3) of the slit portion 15 in the longitudinal direction X is 20 to 70%, particularly 30 to 60%, of the length (total length) in the longitudinal direction X of the absorbent body 10 or absorbent core 11. is preferred. For example, when the total length of the absorbent body 10 or the absorbent core 11 in the vertical direction X is 370 mm, the length 15L of the slit portion 15 in the vertical direction X is preferably 140 mm.
The length of the slit portion 15 in the horizontal direction Y, that is, the width 15W (see FIG. 3) is preferably 2 to 20%, particularly 4 to 10%, of the maximum length or maximum width of the absorbent core 11 in the horizontal direction Y. preferable. For example, when the maximum width of the absorbent core 11 is 120 mm and the minimum width at the constricted portion 11N (see FIG. 3) of the absorbent core 11 is 70 mm, the width 15W of the slit portion may be 5 mm.

The constricted portion 11N is a portion of the absorbent core 11 that is shorter in width (length in the lateral direction Y) than the portions located front and rear across the portion (the constricted portion 11N). In this embodiment, as shown in FIG. 3, the constricted portion 11N has a width that is not constant over the entire length of the constricted portion 11N in the longitudinal direction X, and has a minimum width portion 11Na where the width is the minimum. The minimum width portion 11Na is located at least in the crotch area B.

In this embodiment, a plurality of slit parts 15 are arranged intermittently in the horizontal direction Y, and a plurality of slit parts 15 are formed by dividing the minimum width part 11Na of the absorbent core 11 into a plurality of equal parts in the horizontal direction Y and virtually extending in the vertical direction X. There is a one-to-one correspondence between straight lines (hereinafter also referred to as "straight lines that equally divide the minimum width part"). Here, "one-to-one correspondence" means that one slit part 15 is located on one straight line that equally divides the minimum width part, or is located 5 mm from one straight line that equally divides the minimum width part. means that it is located within the area. To further explain with reference to FIG. 3, in this embodiment, a pair of slit portions 15, that is, two slit portions 15 are arranged intermittently in the lateral direction Y, and the center of each of the two slit portions 15 in the lateral direction Y The two slit horizontal center lines (not shown) that virtually extend in the vertical direction It is divided equally. By arranging the slit portion 15 in this manner in relation to the minimum width portion 11Na, the effects of the slit portion 15 can be achieved even more reliably. For example, when the width of the minimum width portion 11Na (length in the lateral direction Y) is 70 mm, the lateral center lines of the two slit portions (straight lines that equally divide the minimum width portions) adjacent in the lateral direction Y It is preferable that the interval in direction Y is 23 mm.

Note that in the present invention, the number of slit portions 15 is not particularly limited, and may be one or three or more. Further, the plurality of slit portions 15 do not need to be formed symmetrically with respect to the horizontal center line CLy. Further, the plurality of slit portions 15 may have mutually different shapes and dimensions in plan view. Further, in this embodiment, the length (width) of the slit portion 15 in the horizontal direction Y is constant over the entire length of the slit portion 15 in the vertical direction X (longitudinal direction), but it does not have to be constant.

The absorbent core 11 can be manufactured according to a conventional method using a known fiber stacking device equipped with a rotating drum. A fiber stacking device typically has a rotating drum with a stacking recess formed on its outer circumferential surface, and a flow path for conveying core forming material (water-absorbing fibers, water-absorbing polymer) to the stacking recess. duct, and the core is transported by riding on the airflow generated in the flow path by suction from the inside of the rotating drum while rotating the rotating drum around the rotation axis along the circumferential direction of the drum. The forming material is stacked in the stacking recess. The stacked material formed in the stacking recess by this stacking process is the absorbent core 11. The absorbent core 11 can be said to be a stack of core-forming materials. The slit portion 15 is a portion that is formed by intentionally inhibiting the stacking of the forming material in the stacking process. In the absorbent core 11 having the slit portion 15, as the accumulation recess, a portion corresponding to the slit portion 15 at the bottom of the accumulation recess protrudes outward in the radial direction of the rotating drum compared to the peripheral portion. It can be manufactured using In the absorbent core 11 obtained by such a method, the slit portion 15 is a portion where the forming material does not exist or exists with a lower basis weight than the peripheral portion.

As shown in FIGS. 2 and 4, the slit portion 15 has a fused portion 16 in which the skin side core wrap sheet 12 and the non-skin side core wrap sheet 13 are fused. In addition, in this embodiment, as described above, where the two-layer portion 130 in which the fiber layers made of the non-skin side core wrap sheet 13 are laminated is present on the non-skin facing side of the absorbent core 11, the fused portion 16, at least a fiber layer close to the skin-side core wrap sheet 12 of the two-layer portion 130 (a fiber layer in contact with the non-skin facing surface of the absorbent core 11) is a fiber layer made of the skin-side core wrap sheet 12. It is sufficient if it is fused with. In the fused portion 16, a total of three layers, one fibrous layer consisting of the skin-side core wrap sheet 12 and two fibrous layers (two-layer portion 130) consisting of the non-skin side core wrap sheet 13, are fused to each other. There may be cases where Since the skin side core wrap sheet 12 and the non-skin side core wrap sheet 13 are fused together at the fused portion 16 in the slit portion 15, the shape of the slit portion 15 is easily maintained while the diaper 1 is worn. , the shape retention of the absorber 10 can be improved.

The fused portion 16 can be formed by subjecting the absorber 10 to the formation position of the slit portion 15 by applying a compression process that involves melting the constituent fibers of both core wrap sheets 12 and 13. Both core wrap sheets 12 and 13 are typically made of nonwoven fabric, and the constituent fibers thereof are synthetic fibers made of synthetic resin such as thermoplastic resin. As the pressing process, any known method can be used without particular limitation, and examples thereof include embossing with heat and ultrasonic embossing.

As shown in FIG. 4, the fused portion 16 is located closer to the non-skin facing surface (non-skin facing surface) of the absorbent core 11 (absorbent body 10) than the center of the absorbent core 11 (absorbent core 10) in the thickness direction (direction indicated by reference symbol Z in the figure). It is located on the side closer to the skin side core wrap sheet 13). In this way, locating the fused portion 16 on the non-skin-facing surface side of the absorbent core 11 makes it possible to change the formation position of the slit portion 15 in the absorbent body 10 in the pressing process for forming the fused portion 16. This can be achieved by squeezing from the skin-facing surface side toward the non-skin-facing surface side, that is, by pressing the skin-side core wrap sheet 12 against the non-skin side core wrap sheet 13.

In the present invention, the core wrap sheets 12 and 13 facing each other via the slit portion 15 may be joined across the entire slit portion 15, or may be joined only at a portion of the slit portion 15. That is, the fused portion 16 may exist over the entire area of the slit portion 15, or may exist only in a portion of the slit portion 15. FIG. 5 shows an example of the latter form.

In the slit portion 15A shown in FIG. 5, a plurality of fused portions 16 each having a rhombic shape in plan view are arranged in a scattered manner. The shape of the fused portion 16 in plan view is not particularly limited, and can be arbitrarily selected from circular, elliptical, triangular, quadrangular, and the like. Further, the number of fused parts 16 arranged in the slit part 15A is not particularly limited either. The area of each of the plurality of fused parts 16 is preferably 1.0 mm ² or more, more preferably 1.5 mm from the viewpoint of the balance between the bonding strength in the fused part 16 and the liquid drawing ability in the slit part 15A. ² or more, and preferably 40 mm ² or less and 25 mm ² or less.

One of the main features of the slit portion 15A is that, as shown in FIG. 5, a region 15X where the fused portion 16 does not exist exists at the end of the slit portion 15A in the longitudinal direction X. The non-existing region 15X is a region where the fused portion 16 does not exist over the entire length of the slit portion 15A in the lateral direction Y. In the illustrated form, non-existence regions 15X exist at both ends of the slit portion 15A in the longitudinal direction X. The presence of the non-existing region 15X at the end of the slit portion 15A in the longitudinal direction X creates a space for the water-absorbing polymer to absorb water and swell, especially when the absorbent core 11 contains a water-absorbing polymer. This makes it easier for the water-absorbing polymer to exhibit its original absorption performance. From the viewpoint of ensuring the effects of the non-existing region 15X, the length 15XL (see FIG. 5) of the non-existing region 15X in the vertical direction is preferably 3 mm or more, more preferably 5 mm or more, The length is preferably 20 mm or less, more preferably 15 mm or less.

Another main feature of the slit portion 15A is that, as shown in FIG. 5, a region 15Y where the fused portion 16 does not exist exists at the end of the slit portion 15A in the horizontal direction Y. The non-existing region 15Y is a region where the fused portion 16 does not exist over the entire length of the slit portion 15A in the vertical direction X. In the illustrated form, non-existence regions 15Y exist at both ends of the slit portion 15A in the lateral direction Y. The presence of the non-existing region 15Y at the end of the slit portion 15A in the lateral direction Y creates a space for the water-absorbing polymer to absorb water and swell, especially when the absorbent core 11 contains a water-absorbing polymer. This makes it easier for the water-absorbing polymer to exhibit its original absorption performance. From the viewpoint of ensuring the effect of the non-existing region 15Y, the length 15YL of the non-existing region 15Y in the lateral direction Y (see FIG. 5) is preferably 1 mm or more, more preferably 1.5 mm. or more, and preferably 2 mm or less, more preferably 1.5 mm or less.

Another main feature of the slit portion 15A is the arrangement pattern of the fused portions 16. The characteristic arrangement pattern of the fused parts 16 is that "a plurality of fused parts 16 are arranged intermittently in the vertical direction X in the slit part 15A, and all of the plurality of fused parts 16 are arranged in the vertical direction X. The projected image formed when the projection is performed is one projection image in which the projected images of each fused portion 16 overlap with each other, and all of the plurality of fused portions 16 are projected in the horizontal direction Y. In this case, the same number of projected images as the plurality of images are formed.

In other words, referring to FIG. 5, the characteristic arrangement pattern of the fused parts 16 in the slit part 15A is "a fused part 16 in which a plurality of fused parts 16 are arranged intermittently in the longitudinal direction X in the slit part 15A". If a welded part existing region 160 exists and one virtual straight line VLx that traverses the welded part existing region 160 in the longitudinal direction X is drawn at an arbitrary position in the welded part existing region 160, This is a pattern in which the straight line VLx and the fused portion 16 overlap. The fused portion existing region 160 (the region surrounded by the dotted line in FIG. 5) is the smallest of the rectangular regions in a plan view that includes all of the plurality of fused portions 16 arranged in the slit portion 15A, This is an area other than the non-existing areas 15X and 15Y of the fused portion 16 in the slit portion 15A.

In this way, in the slit portion 15A, the plurality of fused portions 16 are arranged so as to be spaced apart from each other in the vertical direction This improves the bonding strength at the fused portion 16 between the core wrap sheets 12 and 13 (nonwoven fabric layers) facing each other, improves the liquid drawing ability at the slit portion 15A, and improves the absorption performance of the absorber 10. However, both can be achieved at a high level. Note that, unless otherwise specified, the description of the slit portion 15 applies to the configurations that are not particularly described in the slit portion 15A.

As shown in FIG. 4, in a region that overlaps with the slit portion 15 in plan view (a region that overlaps with a virtual extension line when the slit portion 15 is virtually extended in the vertical direction in FIG. 4), the top sheet 3 and The skin side core wrap sheet 12 is not joined, and the back sheet 4 and the non-skin side core wrap sheet 13 are joined.

As shown in FIGS. 1 to 4, the non-skin side core wrap sheet 13 and the absorbent core 11 are integrally recessed on the non-skin facing surface (the surface facing the back sheet 4) of the absorbent body 10. A side recess 20 is formed. The non-skin side recess 20 does not penetrate the absorbent core 10 (absorbent core 11), has an opening on the non-skin facing surface of the absorbent core 10, and has a bottom on the opposite side to the opening.

In this embodiment, the non-skin-side recess 20 includes a linear non-skin-side recess that extends in one direction in a plan view of the absorbent body 10 as shown in FIG. In the illustrated form, all of the non-skin-side recesses 20 formed on the non-skin-facing surface of the absorbent body 10 are linear non-skin-side recesses. On the non-skin facing surface of the absorbent body 10, a continuous linear non-skin side concave portion 20 extending in a first direction intersecting both the longitudinal direction X and the lateral direction Y is provided in a direction orthogonal to the first direction. Continuous linear non-skin side recesses 20 are arranged intermittently in the longitudinal direction The non-skin side recesses 20 are arranged intermittently in the direction, and the non-skin side recesses 20 are arranged in a grid pattern in a plan view of the non-skin facing surface of the absorbent body 10.

The non-skin side concave portion 20 is formed by compressing the absorbent body 10 from the non-skin facing side (the non-skin side core wrap sheet 13 side) of the absorbent body 10. It can be called a "squeezing section." The non-skin-side recessed portion 20, which is the compressed portion, has a higher density than the surrounding area of the non-skin-side recessed portion 20 in the absorber 10. That is, the absorbent body 10 has a high-density portion corresponding to the non-skin side concave portion 20 and a low-density portion where the non-skin side concave portion 20 is not formed, and a density difference occurs in the surface direction of the absorbent body 10. ing.

The pressing process for forming the non-skin side recesses 20 may be performed using a method that involves melting the forming material of the absorbent core 10, or may use a method that does not involve melting the forming material. Specific examples of the compression process involving melting of the material forming the absorber 10 include known embossing processes such as embossing process accompanied by heat and ultrasonic embossing process. At the bottom of the non-skin-side recess 20 formed by compression processing involving melting of the forming material of the absorber 10, that is, at the portion that overlaps the non-skin-side recess 20, which is a space, in a plan view, the non-skin-side core wrap sheet is used. 13 and the absorbent core 11 can be heat-sealed and integrated.

The diaper 1 is characterized in that it includes the absorbent body 10 having the above-described configuration. Particularly characteristic configurations include the following (1) to (4).
(1) A slit portion 15 is formed in the absorbent core 11, passing through the absorbent core 11 in the thickness direction and extending in the longitudinal direction X.
(2) The fused portion 16 of the skin side core wrap sheet 12 and the non-skin side core wrap sheet 13 present in the slit portion 15 is connected to the non-skin facing surface side of the absorbent core 11 (the non-skin side core wrap sheet 13 side). ) is located in
(3) In the area overlapping with the slit portion 15 in plan view, the top sheet 3 and the skin-side core wrap sheet 12 are not joined, and the back sheet 4 and the non-skin side core wrap sheet 13 are joined. .
(4) A non-skin side recessed portion 20 is formed on the non-skin facing surface of the absorbent body 10, in which the non-skin side core wrap sheet 13 and the absorbent core 11 are integrally recessed.

By providing the above-mentioned (1), the diaper 1 achieves the effect resulting from the function of the slit portion 15 described above. That is, since the slit portion 15 functions as a deformation guiding portion of the absorbent body 10, the absorbent body 10 in which the slit portion 15 is formed easily deforms to follow the shape of the wearer's body when the diaper 1 is worn. The diaper 1 has excellent comfort and fit. Further, since the slit portion 15 functions as a flow path for excrement such as urine, in the absorbent body 10 in which the slit portion 15 extending in the longitudinal direction X is formed, diffusion of excrement in the longitudinal direction X is promoted. . Therefore, the diaper 1 has excellent utilization efficiency of the absorbent body 10.

In addition, one of the main effects of the diaper 1 is that it reduces the stickiness of the skin due to body fluids excreted by the wearer, and reduces the dry feeling of the members (for example, the top sheet 3) that come into contact with the wearer's skin after excreting body fluids such as urine. Although it is said to have excellent effects, such effects are largely dependent on the adoption of the above-mentioned (2) to (4).
That is, since the fused portion 16 has low liquid permeability and is a site where liquid tends to remain once attached, the fused portion 16 is located closer to the skin of the absorbent core 11 than the center of the absorbent core 11 in the thickness direction. If it is located on the side closer to the opposing surface (skin-side core wrap sheet 12), body fluids adhering to the fused portion 16 may adhere to the wearer's skin, causing stickiness. On the other hand, the diaper 1 adopts the above-mentioned (2), and since the fused portion 16 is located relatively far from the wearer's skin, such concerns are eliminated.
Further, in the diaper 1, by employing the above (3), the contact between the topsheet 3 and the fused portion 16 of the slit portion 15 is inhibited, and a space may be formed between the topsheet 3 and the fused portion 16. , liquid return from the absorber 10 side to the topsheet 3 side in the slit portion 15 is suppressed. Further, since the topsheet 3 and the skin-side core wrap sheet 12 are not joined, liquid easily permeates from the topsheet 3 to the slit portion 15, and the liquid is difficult to remain on the topsheet 3.
In addition, the above (4) is adopted in the diaper 1, and the non-skin side concave portion 20 is formed on the non-skin facing surface of the absorbent core 10, so that the non-skin facing surface side of the absorbent core 10 is Liquid diffusivity is enhanced, which makes it easier for liquid to move away from the wearer's skin.

Referring to FIG. 4, in a region overlapping with the slit portion 15 in plan view (a region overlapping with a virtual extension line when the slit portion 15 is virtually extended in the vertical direction in FIG. 4), the top sheet 3 and The amount of adhesive 32 applied between the skin side core wrap sheet 12 is preferably smaller than the amount of adhesive 42 applied between the back sheet 4 and the non-skin side core wrap sheet 13. In this way, in the area overlapping with the slit portion 15 in plan view, the size relationship is ``amount of adhesive 32 applied on the skin side core wrap sheet 12 side<amount of adhesive 42 applied on the non-skin side core wrap sheet 13 side''. By establishing the above, the effects of adopting the above (3) can be more reliably achieved.

In order to more reliably achieve the effect of establishing the above-mentioned size relationship of "Amount of adhesive 32 applied on the skin side core wrap sheet 12 side <Amount of adhesive 42 applied on the non-skin side core wrap sheet 13 side". From the viewpoint of this, there is no adhesive between the top sheet 3 and the skin-side core wrap sheet 12 in the area overlapping with the slit portion 15 in plan view, that is, the amount of adhesive 32 applied in FIG. 4 is zero. It is preferable that

When the applied amount of the adhesive 32 is not zero, the ratio of the applied amount of the adhesive 32 to the applied amount of the adhesive 42 is preferably 0.1 or more, more preferably 0.1 or more as the former/latter, on the premise that the former < the latter. is 0.2 or more, preferably 0.9 or less, more preferably 0.8 or less.
If the coating amount of the adhesive 32 is not zero, it is preferably 0.5 g/m ² or more, more preferably 1 g/m ² or more, and preferably 6 g/m ² or less, more preferably 4 g/m ² or less. be.
The coating amount of the adhesive 42 is preferably 2 g/m ² or more, more preferably 4 g/m ² or more, and preferably 12 g/m ² or less, more preferably 10 g/m ² or less.
In this specification, unless otherwise specified, the "amount of adhesive applied" refers to the mass (basis weight) of the adhesive per unit area only for the part to which the adhesive is applied, and refers to the mass (basis weight) of the adhesive per unit area. Does not include non-coated areas.

Referring to FIG. 4, the amount of adhesive 31 applied between the top sheet 3 and the skin-side core wrap sheet 12 is equal to It is preferable that the amount of adhesive 41 is greater than the amount of adhesive 41 applied between the core wrap sheet 13 and the non-skin side core wrap sheet 13. In this way, in the region where the slit portion 15 is not formed, the size relationship is established: "Amount of adhesive 31 applied on the skin side core wrap sheet 12 side>Amount of adhesive 41 applied on the non-skin side core wrap sheet 13 side" By doing so, the liquid is easily taken into the absorbent body 10 through the slit portion 15, and the liquid diffusivity on the non-skin-facing side of the absorbent body 10 is improved, and liquid return is suppressed. Here, "improvement of liquid diffusivity" is mainly due to a relatively small amount of adhesive 41 applied, and "suppression of liquid return" is mainly due to a relatively small amount of adhesive 42 applied. This is due to many things.

The ratio of the coating amount of the adhesive 31 to the coating amount of the adhesive 41 is preferably 1.5 or more, more preferably 2 or more, and preferably 10 or less as the former/latter, assuming that the former>the latter. More preferably it is 8 or less.
The coating amount of the adhesive 31 is preferably 3 g/m ² or more, more preferably 5 g/m ² or more, and preferably 15 g/m ² or less, more preferably 12 g/m ² or less.
The coating amount of the adhesive 41 is preferably 1 g/m ² or more, more preferably 3 g/m ² or more, and preferably 10 g/m ² or less, more preferably 8 g/m ² or less.

The types of adhesives 31, 32, 41, and 42 are not particularly limited, and any adhesive that is commonly used for bonding members together in this type of absorbent article can be used without any particular restrictions, such as hot melt adhesives. It will be done. Furthermore, the application pattern of these adhesives is not particularly limited, provided that the application amount is set within the above-mentioned preferred range, and the adhesive can be applied to the entire surface to be coated without any gaps (so-called solid coating). Alternatively, the adhesive may be applied in an intermittent pattern such that the adhesive is applied in a predetermined shape such as a stripe, a spiral, an omega shape, or a dot in plan view.

The non-skin side concave portion 20 may be formed over the entire skin-facing surface of the absorbent body 10, or may be formed only on a part of the skin-facing surface. The non-skin side concave portion 20 is preferably formed at least in the portion facing the excretory portion, and more preferably formed in the crotch region B. In this embodiment, as shown in FIG. 1, a non-skin side recess 20 is formed in the entire non-skin facing surface of the absorbent body 10, and therefore a non-skin side recess 20 is formed in the crotch area B. There is. Since the non-skin side recess 20 is formed in the area facing the excretory part in the diaper 1 where body fluids are particularly likely to concentrate, the function of the non-skin side recess 20 is effectively utilized, and the absorption body 10 is Liquid diffusivity can be effectively improved.

In this embodiment, the non-skin side recess 20 includes a linear non-skin side recess that extends in one direction in a plan view of the absorbent body 10 as shown in FIG. 20 intersects with the slit portion 15. More specifically, in this embodiment, as shown in FIG. 3, the linear non-skin side concave portion 20 extends from one location on the periphery of the absorbent core 11 to another location on the periphery. There is. That is, the plurality of linear non-skin side recesses 20 each extend over the entire length of the skin-facing surface of the absorbent core 11 in the first direction or the second direction. The linear non-skin side concave portion 20 intersects with the slit portion 15. In other words, on the non-skin facing surface of the absorbent core 10, there is a linear non-skin side concave portion 20 that extends from one location on the periphery of the absorbent core 11 to another location on the periphery after passing through the slit portion 15. is formed. In the illustrated form, a plurality of linear non-skin side recesses 20 passing through such slits 15 are formed. With such a configuration, it becomes possible to diffuse the liquid present in the slit portion 15 throughout the absorbent body 10 through the non-skin side recessed portion 20, improving the liquid diffusivity in the surface direction of the absorbent body 10, and improving liquid absorption. This leads to improved performance.

From the viewpoint of ensuring that the above-mentioned non-skin-side recessed portion 20 exerts its effects more reliably, the linear non-skin-side recessed portion 20 not only intersects with the slit portion 15 but also crosses the slit portion 15. It is more preferable that the fused portion 16 intersects with the fused portion 16 present in the fused portion 16 . That is, it is more preferable that the imaginary extension line of the non-skin side recessed part 20 intersects with the fused part 16.

In this embodiment, when an imaginary straight line (for example, line II in FIG. 1) passing through the slit portion 15 and crossing the absorbent core 11 in the horizontal direction Y is drawn, as shown in FIG. In a straight cross-sectional view, there are portions where the number of non-skin side recesses 20 is greater than the number of slits 15. In the form shown in FIG. 2, there are two slit parts 15, but four non-skin side recesses 20, and the size relationship is "number of non-skin side recesses 20>number of slit parts 15". has been established. By establishing such a size relationship, it becomes more reliable to first diffuse the liquid in the slit portion 15 (primary diffusion) and then to diffuse the liquid in the non-skin side recessed portion 20 (secondary diffusion). As a result, the liquid diffusivity in the surface direction of the absorber 10 can be further improved.

In this embodiment, as shown in FIG. 3, there are slit-free regions 110 in which slits 15 are not formed over the entire length in the lateral direction Y at both ends of the absorbent core 11 in the vertical direction X. Non-skin side recesses 20 are formed in each of the slit-free areas 110 at both ends in the longitudinal direction. In this embodiment, as shown in FIG. 3, the non-skin side recesses 20 are formed in the entire skin-facing surface of the absorber 10, and therefore the non-skin side recesses 20 are formed in the slit-free region 110. has been done. By forming the non-skin side concave portion 20 in the slit-free region 110 at the end of the absorbent core 11 in the longitudinal direction X, the above-mentioned primary diffusion and secondary diffusion occur in the region 110, This improves the liquid diffusivity in the surface direction of the absorber 10, and the liquid absorption performance of the absorber 10 can be further improved.

In this embodiment, as shown in FIG. 1, a plurality of (two in the illustrated form) slit portions 15 are arranged intermittently in the lateral direction Y in the crotch region B, and as shown in FIGS. , in a region that overlaps in plan view between a plurality of (two) slit portions 15 adjacent to each other in the lateral direction Y, a plurality of layers made of non-skin side core wrap sheets 13 are bonded to each other at non-skin side recessed portions 20. It is fused. In the illustrated form, a part of the two-layer portion 130 of the non-skin side core wrap sheet 13 is recessed in the non-skin side recessed portion 20, and the two-layer portion 130 located in the non-skin side recessed portion 20 is configured. The skin-side core wrap sheets 13 are fused to each other. Such fusion of the skin side core wrap sheets 13 is due to the pressing process accompanied by melting of the material forming the absorbent body 10 when forming the non-skin side recessed portions 20. In this way, the plurality of layers made of the non-skin side core wrap sheets 13 arranged correspondingly between the plurality of slit parts 15 are fused to each other at the non-skin side recessed part 20. As a result, the distance between the constituent fibers of the non-skin-side core wrap sheet 13 in the non-skin-side recessed portion 20 becomes shorter, and further improvement in the liquid diffusivity of the absorbent body 10 can be expected.

In this embodiment, the non-skin side recess 20 includes a linear non-skin side recess that extends in one direction in a plan view of the absorbent body 10 as shown in FIG. The width of 20 (i.e., the length in the direction orthogonal to the longitudinal direction of the linear non-skin side recessed part 20) 20W (see FIG. 3) is not particularly limited, but from the viewpoint of further improving liquid dispersibility and absorption. From the viewpoint of ensuring shape retention and flexibility of the body 10, it is preferable that the width is narrower than the width 15W of the slit portion 15 (see FIG. 3). Specifically, the width 20W of the non-skin side recess 20 is preferably 20% or more, more preferably 30% or more, and preferably 80% or less, more preferably It is 70% or less. The width 20W of the non-skin side recessed portion 20 is preferably 0.5 mm or more, more preferably 1 mm or more, and preferably 5 mm or less, more preferably 4 mm or less.

From the same viewpoint, the depth 20D (FIG. 4) of the non-skin side recessed portion 20 is preferably 20% or more, more preferably 30% or more, and preferably is 80% or less, more preferably 50% or less. The depth 20D of the non-skin side recess 20 is preferably 1.5 mm or more, more preferably 1 mm or more, and preferably 8 mm or less, more preferably 5 mm or less.

Referring to FIG. 3, the intersection angle θ between the linear non-skin side recess 20 and the horizontal virtual straight line VL passing through the non-skin side recess 20 and extending in the lateral direction Y is preferably 45 degrees or more, More preferably, it is 60 degrees or more. The intersection angle θ may be 90 degrees, that is, the linear non-skin side recessed portion 20 may extend parallel to the longitudinal direction X. The intersecting angle θ here means an acute intersecting angle between an acute angle and an obtuse angle formed when the linear non-skin side recessed portion 20 intersects with the lateral virtual straight line VL. The fact that the intersection angle θ is within the above range means that the linear non-skin side recessed portion 20 extends along the vertical direction X. By setting the intersection angle θ within the above range, the above-mentioned primary diffusion and secondary diffusion can be performed more reliably, and the diffusivity of the liquid in the vertical direction X can be further improved.

From the viewpoint of promoting the diffusion of liquid on the non-skin facing side of the absorbent body 10 and keeping excreta such as urine away from the skin of the wearer, the non-skin facing side of the absorbent body 10 is It is preferable that the liquid diffusivity is higher than that on the opposing surface side. Whether this relationship of "liquid diffusivity on the non-skin-facing side of the absorber 10>liquid diffusivity on the skin-facing side of the absorber 10" holds true is determined by the method below. It can be evaluated using the liquid diffusion area as an index. That is, when the size relationship holds: "liquid diffusion area on the non-skin facing surface side of the absorbent body 10 (back sheet 4 side)>liquid diffusion area on the skin facing surface side of the absorbent body 10 (top sheet 3 side)", It can be evaluated that the magnitude relationship regarding the liquid diffusivity of the absorber 10 is established.

<Method for measuring liquid diffusion area of absorber>
From an absorbent article such as a disposable diaper, the top sheet and back sheet are removed by melting with a solvent or hot air from a dryer, etc., and the absorbent body is taken out. Using the taken-out absorbent body as a sample, the liquid diffusion area is measured on the skin-facing side (top sheet side) and the non-skin-facing side (back sheet side) of the absorbent body. Specifically, 100 g of physiological saline is dropped at the center of both the vertical and horizontal directions on one surface side (skin-facing surface side or non-skin-facing surface side) of the taken-out absorbent body. The saline solution to be dropped is colored with a dye such as Blue No. 1 or methylene blue. After 10 minutes, the area of the dropped physiological saline is measured using the image processing function of Image-J on the side of the absorber onto which the physiological saline has been dropped. Similarly, physiological saline is dropped on the other side of the absorbent sample, and the area thereof is measured. The above measurements are carried out three times on one side of the absorber, and the average value of the three measurements is taken as the liquid diffusion area on that side of the absorber. Note that the measurement environment temperature is 22°C.

From the same point of view, the portion of the non-skin side core wrap sheet 13 that overlaps with the slit portion 15 in plan view is the portion of the non-skin side core wrap sheet 13 that overlaps with the non-slit portion 15 (the area where the slit portion 15 is not formed). It is preferable that the liquid diffusivity is higher than that of the part). In the non-skin side core wrap sheet 13, does this size relationship of "liquid diffusivity in a portion that overlaps with the slit portion 15 in plan view>liquid diffusivity in a portion that overlaps in plan view with a portion other than the slit portion 15" hold? This can be evaluated by the following method. The evaluation can be made using the KREM water absorption height of the core wrap sheet as an index, which is measured by the following method. In other words, "Klemm water absorption height of the portion of the non-skin side core wrap sheet 13 that overlaps with the slit portion 15 in plan view> Clem water absorption height of the portion of the non-skin side core wrap sheet 13 that overlaps with the portion other than the slit portion in plan view. '', it can be evaluated that the magnitude relationship regarding the liquid diffusivity of the non-skin side core wrap sheet 13 is established.

<Method for measuring KREM water absorption height of core wrap sheet>
The non-skin side core wrap sheet to be measured is taken out from an absorbent article such as a disposable diaper. If the non-skin side core wrap sheet and the skin side core wrap sheet are one continuous sheet, take out that one sheet. If the core wrap sheet to be removed from the absorbent article is bonded to other members such as a top sheet and a back sheet, the bonded portions are removed by melting with a solvent or hot air from a dryer or the like. The core wrap sheet taken out (the part that overlaps in plan view with the slit part on the non-skin side core wrap sheet, or the part that overlaps in plan view with the part other than the slit part in the non-skin side core wrap sheet) was used as a sample, and the JIS P 8141. Measure the Klemm water absorption height according to the test method. Specifically, the length of the absorbent article in which the sample was incorporated is 30 mm in the longitudinal direction (the front-back direction of the wearer), and the length in the lateral direction (direction perpendicular to the longitudinal direction) of the absorbent article is 30 mm. Cut it to a length of 150mm. Note that if the sample cannot be cut to such a size because it is too small, it is cut to a measurable size. When cutting the sample, cutting methods that may crush the sample, such as a push-cut cutter, are not preferred as they are likely to affect the results. Therefore, when cutting the sample, use a knife, cutter, razor, etc. to avoid crushing the cut surface of the sample. Next, the cut sample is set in a jig specified in JIS P 8141, and water is used as a test liquid to measure the water absorption height after 60 seconds. In order to easily determine the suction height, the test liquid may be appropriately colored with a dye such as Blue No. 1 or methylene blue. The above measurement is carried out five times, and the average value is taken as the KREM water absorption height of the sample. Note that the measurement environment temperature is 22°C.

In this embodiment, as shown in FIG. 4, there is a two-layer portion 130 on the non-skin-facing surface side of the absorbent core 11 in which fiber layers made of the non-skin-side core wrap sheet 13 are laminated. In the wearing part 16, a total of three layers, one fibrous layer made of the skin-side core wrap sheet 12 and two fibrous layers (two-layer portion 130) made of the non-skin side core wrap sheet 13, are fused. It is preferable. This promotes the diffusion of the liquid on the side of the non-skin facing side of the absorber 10, making it possible to keep the liquid away from the wearer's skin. ＞Liquid diffusivity on the skin-facing side of the absorber 10'' and ``liquid diffusivity in the portion that overlaps with the slit portion 15 in plan view'' of the non-skin-side core wrap sheet 13>Regarding the portion other than the slit portion 15. A size relationship of "liquid diffusivity of the overlapping portion in plan view" can be established.

FIG. 6 shows the skin-facing side of an absorbent body 10A, which is another embodiment of the absorbent body according to the present invention. Regarding other embodiments to be described later, components different from those of the embodiment (absorbent core 10) will be mainly explained, and similar components will be given the same reference numerals and explanations will be omitted. For configurations that are not particularly described in other embodiments to be described later, the descriptions of the previous embodiments apply as appropriate.

In the absorbent body 10, the non-skin side concave portion 20 was formed in the entire non-skin facing surface of the absorbent body 10 (see FIG. 3), but in the absorbent body 10A, the non-skin side recessed portion 20 was formed in the entire non-skin facing surface of the absorbent body 10A. A non-skin side concave portion 20 is partially formed in a part of the body. Specifically, as shown in FIG. 6, a region in which the linear non-skin side recesses 20 are formed in a lattice shape in plan view and a non-formed region 21 of the non-skin side recesses 20 are arranged in the vertical direction are arranged alternately. The absorbent body 10A having such a configuration also basically provides the same effects as the absorbent body 10.

The absorbent article of the present invention is not limited to the expandable disposable diaper as in the above embodiment, but broadly includes articles used for absorbing body fluids (urine, menstrual blood, soft stool, sweat, etc.) discharged from the human body, It also includes pants-type disposable diapers, sanitary napkins, sanitary shorts, etc. that do not have a fastening structure such as the fastening member 8 and the fastening region 9.

Although the present invention has been described above based on its preferred embodiments, the absorbent article of the present invention is not limited to the above embodiments and can be modified as appropriate.
For example, from the perspective of improving absorbency and leak-proofing properties, paper or various non-woven fabrics, also called second sheets or sublayer sheets, may be used between the top sheet 3 and the absorbent body 10 (skin-side core wrap sheet 12). A liquid permeable sheet may be interposed therebetween.
All parts that only one of the embodiments described above has can be used mutually as appropriate. Regarding the embodiments of the present invention described above, the following additional notes are further disclosed.

<1>
It has a vertical direction extending from the ventral side of the wearer to the dorsal side via the crotch area and a horizontal direction perpendicular to the vertical direction, and has a crotch area disposed in the groin area and a crotch area extending from the wearer's crotch area to the wearer's back side through the crotch area. an absorbent body divided into a ventral part disposed on the ventral side and a dorsal part disposed on the dorsal side of the wearer from the crotch area, and extending in the longitudinal direction through the crotch area; An absorbent article comprising a top sheet disposed on the skin-facing side of the body and a back sheet disposed on the non-skin-facing side of the absorbent body,
The absorbent body includes an absorbent core that absorbs and retains body fluids, a skin-side core wrap sheet that covers the skin-facing surface of the absorbent core, and a non-skin-side core wrap that covers the non-skin-facing surface of the absorbent core. Consisting of a sheet and
A slit portion is formed in the absorbent core, penetrating the absorbent core in the thickness direction and extending in the longitudinal direction,
A fused portion in which the skin-side core wrap sheet and the non-skin-side core wrap sheet are fused exists in the slit portion, and the fused portion has a lower absorbent area than the center in the thickness direction of the absorbent core. It is located on the side of the core that is close to the non-skin facing surface,
In a region overlapping with the slit portion in plan view, the top sheet and the skin side core wrap sheet are not joined, and the back sheet and the non-skin side core wrap sheet are joined,
An absorbent article, wherein a non-skin-side recessed portion is formed on a non-skin-facing surface of the absorbent body, in which the non-skin-side core wrap sheet and the absorbent core are integrally recessed.
<2>
In the area overlapping with the slit portion in plan view, the amount of adhesive (adhesive 32) applied between the top sheet and the skin side core wrap sheet is the same as that of the back sheet and the non-skin side core wrap sheet. The absorbent article according to <1> above, wherein the amount of the adhesive (adhesive 42) applied is smaller than that of the adhesive between the adhesives (adhesive 42).
<3>
When the amount of adhesive (adhesive 32) applied between the top sheet and the skin side core wrap sheet is not zero, the amount of the adhesive 32 applied, the back sheet and the non-skin side core wrap sheet The ratio of the applied amount of adhesive (adhesive 42) between The absorbent article according to <2> above, wherein the absorbent article is 0.9 or less, more preferably 0.8 or less.
<4>
The amount of adhesive (adhesive 32) applied between the top sheet and the skin-side core wrap sheet is preferably 0.5 g/m ² or more, more preferably 1 g/m ² or more, and preferably 6 g. /m ² or less, more preferably 4 g/m ² or less, the absorbent article according to any one of <1> to <3>.
<5>
The absorbent article according to <1> or <2>, wherein an adhesive (adhesive 32) is not present between the top sheet and the skin-side core wrap sheet in a region overlapping with the slit portion in plan view. .
<6>
The amount of adhesive (adhesive 42) applied between the back sheet and the non-skin side core wrap sheet is preferably 2 g/m ² or more, more preferably 4 g/m ² or more, and preferably 12 g/m 2 or more. The absorbent article according to any one of <1> to <5>, wherein the absorbent article is at most 10 g/m ² , preferably at most 10 g/m ² .

<7>
In a region other than the slit portion in a region that overlaps with the absorbent body in a plan view, the amount of adhesive (adhesive 31) applied between the top sheet and the skin-side core wrap sheet is equal to that of the back sheet and the non-slit portion. The absorbent article according to any one of <1> to <6>, wherein the amount of the adhesive (adhesive 41) applied to the skin-side core wrap sheet is larger than the amount applied.
<8>
In a portion other than the slit portion in a region overlapping with the absorbent body in a plan view, the amount of adhesive (adhesive 31) applied between the top sheet and the skin-side core wrap sheet, and the amount of adhesive applied to the back sheet and the non-slit portion are determined. The ratio of the applied amount of the adhesive (adhesive 41) to the skin side core wrap sheet is preferably 1.5 or more, more preferably 2 or more as the former/latter, assuming that the former > the latter. , preferably 10 or less, more preferably 8 or less.
<9>
In a portion other than the slit portion in a region overlapping with the absorbent body in plan view, the amount of adhesive (adhesive 31) applied between the top sheet and the skin-side core wrap sheet is preferably 3 g/m ² The absorbency according to any one of <1> to <8> above, more preferably 5 g/m ² or more, and preferably 15 g/m ² or less, more preferably 12 g/m ² or less Goods.
<10>
The amount of adhesive (adhesive 41) applied between the back sheet and the non-skin side core wrap sheet is preferably 1 g/m in a region other than the slit portion in a region overlapping with the absorbent body in plan view. ² or more, more preferably 3 g/m ² or more, and preferably 10 g/m ² or less, more preferably 8 g/m ^{2 or} less, according to any one of <1> to <9> above. Sex items.

<11>
When an imaginary straight line passing through the slit portion and crossing the absorbent core in the lateral direction is drawn, the number of the non-skin side recessed portions is larger than that of the slit portion in a cross-sectional view along the imaginary straight line. The absorbent article according to any one of <1> to <10>, wherein the absorbent article has a portion with a large amount of.
<12>
A slit-free region in which the slit portion is not formed exists over the entire length of the absorbent core in the vertical direction, and the non-skin side recess is in the slit-free region. The absorbent article according to any one of <1> to <11>, which is formed.
<13>
A plurality of slits are arranged intermittently in the lateral direction in the crotch area, and in a region that overlaps in plan view between the plurality of slits adjacent to each other in the lateral direction, from the non-skin side core wrap sheet. The absorbent article according to any one of <1> to <12>, wherein the plurality of layers are fused to each other in the non-skin side recessed portion.

<14>
The non-skin side recess includes a linear non-skin side recess that extends in one direction in plan view,
The absorbent article according to any one of <1> to <13>, wherein the linear non-skin side recessed portion is narrower than the slit portion.
<15>
The width of the linear non-skin side recess (the length in the direction perpendicular to the longitudinal direction of the linear non-skin side recess) is the width of the slit (the length of the slit in the lateral direction). ), preferably 20% or more, more preferably 30% or more, and preferably 80% or less, more preferably 70% or less.
<16>
In <14> or <15> above, the width of the linear non-skin side recess is preferably 0.5 mm or more, more preferably 1 mm or more, and preferably 5 mm or less, more preferably 4 mm or less. Absorbent article as described.
<17>
The depth of the non-skin side recess is preferably 20% or more, more preferably 30% or more, and preferably 80% or less, more preferably 50% or less of the thickness of the absorbent body. The absorbent article according to any one of <1> to <16> above.
<18>
Any one of <1> to <17> above, wherein the depth of the non-skin side recess is preferably 1.5 mm or more, more preferably 1 mm or more, and preferably 8 mm or less, more preferably 5 mm or less. The absorbent article according to item 1.

<19>
The non-skin side recess includes a linear non-skin side recess that extends in one direction in plan view,
The absorbent article according to any one of <1> to <18>, wherein the linear non-skin side recess portion intersects with the slit portion.
<20>
The absorbent article according to <19>, wherein the linear non-skin side concave portion intersects with the fused portion present in the slit portion.
<21>
The absorbent article according to <19> or <20>, wherein an intersection angle between the linear non-skin side recess and a virtual straight line extending laterally through the non-skin side recess is 45 degrees or more. .
<22>
According to any one of <19> to <21>, wherein the linear non-skin side recess and an imaginary straight line extending laterally through the non-skin side recess have an intersection angle of 60 degrees or more. Absorbent article as described.

<23>
The length of the slit portion in the longitudinal direction is preferably 20 to 70%, more preferably 30 to 60% of the length of the absorbent core or the absorbent core. The absorbent article according to any one of items 1> to <22>.
<24>
The lateral length (width) of the slit portion is preferably 2 to 20%, more preferably 4 to 10% of the lateral maximum length (maximum width) of the absorbent core. The absorbent article according to any one of <1> to <23> above.
<25>
Any one of <1> to <24> above, wherein the area of the fused portion is preferably 1.0 mm ² or more, more preferably 1.5 mm ² or more, and preferably 40 mm ² or less, 25 mm ² or less. The absorbent article according to item 1.
<26>
The absorbent article according to any one of <1> to <25>, wherein a region where the fused portion is not present exists at the longitudinal end of the slit portion.
<27>
The length in the vertical direction of the region where the fused portion does not exist, which exists at the end portion in the vertical direction of the slit portion, is preferably 3 mm or more, more preferably 5 mm or more, and preferably 20 mm or less, and more preferably The absorbent article according to <26> above, preferably having a length of 15 mm or less.
<28>
The absorbent article according to any one of <1> to <27>, wherein a region where the fused portion is absent exists at the end portion of the slit portion in the lateral direction.
<29>
The length in the lateral direction of the region where the fused portion does not exist, which is present at the lateral end of the slit portion, is preferably 1 mm or more, more preferably 1.5 mm or more, and preferably 2 mm or less. , more preferably 1.5 mm or less, the absorbent article according to <28> above.

<30>
Any one of <1> to <29> above, wherein in the slit portion, the plurality of fused portions are arranged so as to be spaced apart from each other in the vertical direction and continuous without gaps in the horizontal direction. The absorbent article according to item 1.
<31>
A plurality of the fused parts are arranged intermittently in the longitudinal direction in the slit part,
A projected image formed when all of the plurality of fused parts are projected in the vertical direction is one projected image in which the projected images of each of the fused parts overlap each other, and the plurality of fused parts The absorbent article according to <30>, wherein when all of the fused portions are projected in the lateral direction, the same number of projected images as the plurality of images are formed.
<32>
A fused portion existing region exists in the slit portion in which a plurality of fused portions are arranged intermittently in the longitudinal direction, and the fused portion existing region is arranged at an arbitrary position in the fused portion existing region in the longitudinal direction. The absorbent article according to <30>, wherein when one imaginary straight line is drawn longitudinally through the fused portion, the imaginary straight line and the fused portion overlap.
<33>
The absorbent article according to any one of <1> to <32>, wherein the non-skin facing side of the absorbent body has higher liquid diffusivity than the skin facing side of the absorbent body.
<34>
Any of <1> to <33> above, wherein a portion of the non-skin side core wrap sheet that overlaps with the slit portion in plan view has higher liquid diffusivity than a portion other than the portion of the non-skin side core wrap sheet. The absorbent article according to item 1.
<35>
In any one of the above <1> to <34>, wherein in the fused portion, one layer consisting of the skin side core wrap sheet and two layers consisting of the non-skin side core wrap sheet are fused. Absorbent article as described.

1 Disposable diapers (absorbent articles)
2 Absorbent main body 3 Top sheet 4 Back sheet 5 Flap part 6 Leak-proof cuff 10, 10A Absorbent body 11 Absorbent core 12 Skin side core wrap sheet 13 Non-skin side core wrap sheet 15, 15A Slit part 16 Fusion part 20 Non Skin-side recess 21 Non-skin-side recess non-formation areas 31, 32, 41, 42 Adhesive A Ventral part B Crotch C Dorsal part X Vertical direction Y Lateral direction

Claims (12)

It has a vertical direction extending from the ventral side of the wearer to the dorsal side via the crotch area and a horizontal direction perpendicular to the vertical direction, and has a crotch area disposed in the groin area and a crotch area extending from the wearer's crotch area to the wearer's back side through the crotch area. an absorbent body divided into a ventral part disposed on the ventral side and a dorsal part disposed on the dorsal side of the wearer from the crotch area, and extending in the longitudinal direction through the crotch area; An absorbent article comprising a top sheet disposed on the skin-facing side of the body and a back sheet disposed on the non-skin-facing side of the absorbent body,
The absorbent body includes an absorbent core that absorbs and retains body fluids, a skin-side core wrap sheet that covers the skin-facing surface of the absorbent core, and a non-skin-side core wrap that covers the non-skin-facing surface of the absorbent core. Consisting of a sheet and
A slit portion is formed in the absorbent core, penetrating the absorbent core in the thickness direction and extending in the longitudinal direction,
A fused portion in which the skin-side core wrap sheet and the non-skin-side core wrap sheet are fused exists in the slit portion, and the fused portion has a lower absorbent area than the center in the thickness direction of the absorbent core. It is located on the side of the core that is close to the non-skin facing surface,
In a region overlapping with the slit portion in plan view, the top sheet and the skin side core wrap sheet are not joined, and the back sheet and the non-skin side core wrap sheet are joined,
A non-skin-side recessed portion is formed on the non-skin-facing surface of the absorbent body, and the non-skin-side core wrap sheet and the absorbent core are integrally recessed ;
In a region other than the slit portion in a region overlapping with the absorbent body in plan view, the amount of adhesive applied between the top sheet and the skin-side core wrap sheet is equal to the amount of adhesive applied to the back sheet and the non-skin side core wrap sheet. The amount of adhesive applied between the absorbent article is large compared to the amount of adhesive applied between the absorbent article and the adhesive. In the area overlapping with the slit portion in plan view, the amount of adhesive applied between the top sheet and the skin side core wrap sheet is equal to the amount of adhesive between the back sheet and the non-skin side core wrap sheet. The absorbent article according to claim 1, wherein the amount of the absorbent article is small compared to the amount of application. The absorbent article according to claim 1 or 2, wherein no adhesive is present between the top sheet and the skin-side core wrap sheet in a region overlapping with the slit portion in plan view. When an imaginary straight line passing through the slit portion and crossing the absorbent core in the lateral direction is drawn, the number of the non-skin side recessed portions is larger than that of the slit portion in a cross-sectional view along the imaginary straight line. The absorbent article according to any one of claims 1 to 3 , wherein the absorbent article has a portion with a large amount of. A slit-free region in which the slit portion is not formed exists over the entire length of the absorbent core in the vertical direction, and the non-skin side recess is in the slit-free region. The absorbent article according to any one of claims 1 to 4 , which is formed. A plurality of slits are arranged intermittently in the lateral direction in the crotch area, and in a region that overlaps in plan view between the plurality of slits adjacent to each other in the lateral direction, from the non-skin side core wrap sheet. The absorbent article according to any one of claims 1 to 5 , wherein the plurality of layers are fused to each other in the non-skin side recess. The non-skin side recess includes a linear non-skin side recess that extends in one direction in plan view,
The absorbent article according to any one of claims 1 to 6 , wherein the linear non-skin side recessed portion is narrower than the slit portion. The non-skin side recess includes a linear non-skin side recess that extends in one direction in plan view,
The absorbent article according to any one of claims 1 to 7 , wherein the linear non-skin side recess portion intersects with the slit portion. The absorbent article according to claim 8 , wherein an intersection angle between the linear non-skin side recess and a virtual straight line extending laterally through the non-skin side recess is 45 degrees or more. The absorbent article according to any one of claims 1 to 9 , wherein the non-skin facing side of the absorbent body has higher liquid diffusivity than the skin facing side of the absorbent body. Any one of claims 1 to 10 , wherein a portion of the non-skin side core wrap sheet that overlaps with the slit portion in plan view has higher liquid diffusivity than a portion other than the portion of the non-skin side core wrap sheet. The absorbent article described in . The absorbent according to any one of claims 1 to 11 , wherein in the fused portion, one layer consisting of the skin side core wrap sheet and two layers consisting of the non-skin side core wrap sheet are fused. Sex items.

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