JP7125310B2 - Pad type absorbent article - Google Patents

Description

The present invention relates to pad-type absorbent articles such as sanitary napkins.

Disposable diapers, which are required to have a high absorption capacity, are generally designed to increase the total amount of absorbent material contained in the absorbent body. If the total amount of absorbent material is large, the absorber becomes hard. Therefore, a technology has been adopted in which the crotch part of the wearer has a constricted shape along the circumference of the leg to reduce discomfort when worn (for example, Patent Document 1). .
On the other hand, so-called pad-type absorbent articles, such as sanitary napkins, which are used inside underwear, generally require less absorption capacity than diapers. Rectangular absorbent bodies are often employed because the absorbent bodies are not as stiff as diapers. For example, Patent Literature 2 discloses an absorbent core having a uniform width in the front-rear direction. For the purpose of preventing lateral leakage, the absorbent core has a V-shaped opening on the skin surface of the projection arranged in the center in the width direction facing the wearer's excretory part, and on both sides of the projection. It has a high density part.

JP 2010-131206 A JP 2015-112235 A

Even during the menstrual period, there are many occasions when women have to do the same activities as during the non-menstrual period, regardless of whether they are on weekdays or holidays. If a pad-type absorbent article such as a sanitary napkin is provided with a rectangular absorbent body, the wearer may feel discomfort due to rubbing of the absorbent article against the groin or excretory region when the absorbent article is worn for a long time. given and may interfere with vigorous activity. Therefore, a technique for reducing friction between absorbent articles and the skin is desired.

An object of the present invention is to provide a pad-type absorbent article capable of reducing friction between the absorbent article and the wearer's skin.

A pad-type absorbent article according to one aspect of the present invention comprises an absorbent core having a front core portion and a rear core portion positioned on both end side in the front-rear direction, and an intermediate core portion.
The intermediate core portion is positioned between the front core portion and the rear core portion.
The intermediate core portion has a shorter width in the width direction perpendicular to the front-rear direction than the front core portion and the rear core portion.
The intermediate core portion is located in the central region in the width direction and has a high basis weight portion having a higher basis weight than the front core portion and the rear core portion, and is located in both side regions in the width direction and has a higher basis weight than the high basis weight portion. and a low basis weight portion having a low basis weight.
The high basis weight portion is thinner than the high basis weight and high thickness portion located in the center in the width direction and the high basis weight and high thickness portion located on both sides in the width direction of the high basis weight and high thickness portion. and a low thickness portion.

As described above, according to the pad-type absorbent article of the present invention, friction between the napkin and the skin can be reduced.

1 is a plan view of a pad-type absorbent article according to one embodiment of the present invention; FIG. FIG. 2 is a schematic plan view of an absorbent body forming a part of the pad-type absorbent article of FIG. 1 in a single state; FIG. 3 is a schematic cross-sectional view of the absorbent body of FIG. 2 cut along the line III-III passing through the linear portion of the peripheral groove provided in the absorbent core, and conceptually showing the relationship between the absorbent core and the core wrap sheet. is. Fig. 3 is a plan view showing an absorbent core forming part of the absorbent body of Fig. 2; FIG. 4 is an explanatory diagram for explaining a method of forming a high basis weight and low thickness portion by compressing both widthwise side portions of a high basis weight portion located in a widthwise central portion of an intermediate core portion of an absorbent core; 1 schematically illustrates the cross section of the intermediate core portion and omits the illustration of the groove portion. FIG. 4 is a drawing corresponding to FIG. 3 according to another embodiment of the present invention; Fig. 10 is a plan view showing an absorbent core as a comparative example;

[Overall configuration of napkin]
Hereinafter, in each figure, the X-axis direction is the front-rear direction of the pad-type absorbent article (hereinafter sometimes referred to as an absorbent article) 1, the Y-axis direction is the width direction, and the Z-axis direction is the vertical direction (thickness direction). correspond respectively to The X-axis, Y-axis and Z-axis are orthogonal to each other. In this specification, regarding the Z-axis direction, when the absorbent article 1 is worn, the side closer to the wearer's skin is defined as the upper side, and the side farther from the skin is defined as the lower side.
The absorbent article 1 of this embodiment is configured as a sanitary napkin, and is hereinafter referred to as a napkin 10 .

As shown in FIG. 1, the napkin 10 comprises a main body M, a pair of wing portions W, and a pair of rear flap portions F. As shown in FIG.
The main body M extends in the front-rear direction X and is fixed to the inner surface (wearing surface) of the wearer's underwear when worn. The main body M has an absorber 11 and has a function of absorbing a liquid substance (hereinafter also referred to as "liquid") such as the wearer's menstrual blood.
The main body M has a front region M1, a middle region M2, and a rear region M3, which are divided along the front-rear direction X. As shown in FIG.
The front region M1 is a region arranged in front of the intermediate region M2 (on the wearer's ventral side), and is configured to face the front of the wearer's excretory part when worn.
The intermediate region M2 is configured to face the wearer's excretory part when worn. Note that the intermediate region M2 may be positioned toward the front of the main body M as shown in the drawing, or may be positioned in the central portion of the main body M.
The rear area M3 is an area arranged behind the intermediate area M2 (on the wearer's back side), and is configured to face the wearer's excretory part behind when worn.

The wing portion W is configured to protrude greatly outward in the width direction Y from the intermediate region M2.
The rear flap portion F is configured to bulge outward in the width direction Y from the rear region M3.
In addition, the napkin 10 may not have at least one of the wing portion W and the rear flap portion F.

[Structure of each part of the napkin]
As shown in FIG. 1 , the napkin 10 includes an absorbent body 11 , a topsheet 12 , a backsheet (not shown), a pair of sidesheets 14 , and compression grooves 16 . In the main body M, the napkin 10 has a configuration in which a backsheet, an absorbent body 11 and a topsheet 12 are laminated. The napkin 10 is configured such that the skin-facing surface 12a of the topsheet 12 contacts the wearer's skin when worn.

The absorbent body 11 has a front-rear direction in the X-axis direction and is arranged in the central portion of the napkin 10 in the thickness direction. The absorber 11 absorbs the liquid from the surface on the topsheet 12 side, diffuses it inside, and retains the liquid. The absorbent body 11 will be described later.
The surface sheet 12 is configured as a liquid-permeable sheet material and arranged on the absorbent body 11 . The surface sheet 12 forms an upper outer surface of the napkin 10 in the main body M in the thickness direction.
The backsheet is arranged to face the topsheet 12 in the thickness direction with the absorber 11 interposed therebetween. The backsheet constitutes the outer surface of the napkin 10 below in the thickness direction. The backsheet is joined to the topsheet 12 and the sidesheets 14, for example, at the peripheral edges by adhesive, heat sealing, or the like.
The pair of side sheets 14 face each other in the width direction Y with the top sheet 12 interposed therebetween, and are arranged at the width direction peripheral edges of the napkin 10 .
The compressed groove portion 16 is configured as a linear groove formed by compressing the absorbent body 11 and the surface sheet 12 .

(Basic configuration of absorber)
As shown in FIG. 3 , the absorbent body 11 has an absorbent core 20 and a core wrap sheet 30 .
The absorbent core 20 has the function of absorbing and retaining liquid. The absorbent core 20 may be formed, for example, of a fiber assembly composed of hydrophilic fibers such as pulp fibers, or may have a structure in which the fiber assembly holds a water-absorbent polymer. . A member constituting the absorbent core 20 is hereinafter referred to as an absorbent member.
As shown in FIGS. 2 and 3 , the core wrap sheet 30 is wrapped in the width direction Y of the absorbent core 20 so as to cover the front and back surfaces of the absorbent core 20 . The length of the core wrap sheet 30 along the X-axis direction is formed to be equal to the length (full length) of the absorbent core 20 in the front-rear direction X, but is not limited to this, and is longer than the full length of the absorbent core 20. It can be long or short.
The core wrap sheet 30 covers the absorbent core 20 and has a function of retaining the shape of the absorbent core 20, for example. The core wrap sheet is made of, for example, thin and soft paper such as tissue paper, liquid-permeable nonwoven fabric, or the like. The core wrap sheet 30 may be composed of one sheet material, or may be composed of a plurality of sheet materials. The core wrap sheet 30 may be joined to the top sheet 12 and the back sheet 13 by, for example, an adhesive applied in a predetermined pattern.

(Configuration of absorbent core)
As shown in FIG. 4, the absorbent core 20 has a front core portion 21 positioned in the front region M1, an intermediate core portion 22 positioned in the intermediate region M2, and a rear core portion 23 positioned in the rear region M3. . The front core portion 21 and the rear core portion 23 are positioned on both end side sides of the absorbent core 20 in the front-rear direction X, and the intermediate core portion 22 is positioned between the front core portion 21 and the rear core portion 23 . The intermediate core portion 22 extends from the rear side of the front region M1 to the front side of the rear region M3 via the intermediate region M2. The absorbent core 20 has a planar shape that is symmetrical in the width direction Y. As shown in FIG.

Widths D1, D2, and D3, which are dimensions in the width direction Y of the front core portion 21, the intermediate core portion 22, and the rear core portion 23, are shown in FIG. The width D2 of the intermediate core portion 22 is shorter than both the width D1 of the front core portion 21 and the width D3 of the rear core portion 23 . That is, the absorbent core 20 has an intermediate core portion 22 narrower than the front core portion 21 and the rear core portion 23 and formed between the pair of constricted regions 22s in the front-back direction X intermediate portion.

In this embodiment, the width D1 of the front core portion 21 and the width D3 of the rear core portion 23 are the same. However, the width D1 of the front core portion 21 and the width D3 of the rear core portion 23 may be different. Moreover, the widths of the front core portion 21, the intermediate core portion 22, and the rear core portion 23 may not be uniform. In this case, the maximum dimension in the width direction Y of the front core portion 21 and the rear core portion 23 can be D1 and D3, respectively, and the minimum dimension in the width direction Y of the intermediate core portion 22 can be D2.

The intermediate core portion 22 is an excretion portion facing portion that is arranged to face the vaginal opening, which is the excretion portion of the wearer, when the napkin 10 is worn. The front core portion 21 is arranged closer to the wearer's front side (abdominal side) than the intermediate core portion 22 , and the rear core portion 23 is arranged closer to the wearer's rear side (back side) than the intermediate core portion 22 .

As shown in FIG. 4, the front core portion 21 has a tapered portion 21a at its rear end, and the rear core portion 23 has a tapered portion 23a at its front end. The tapered portion 21 a ( 23 a ) reduces the width of the front core portion 21 (rear core portion 23 ) toward the intermediate core portion 22 . The constricted region 22s corresponds to a space formed between both width direction Y edge portions of the intermediate core portion 22 and the tapered portions 21a and 23a.

A plurality of grooves are provided on the side of the skin-facing surface 20a of the absorbent core 20 .
Specifically, the front core portion 21 , the intermediate core portion 22 and the rear core portion 23 are provided with a longitudinal groove portion 27 and a lateral groove portion 28 , and the intermediate core portion 22 is provided with a peripheral edge groove portion 29 .
Furthermore, a boundary groove portion 60 is provided at the boundary portion P1 between the front core portion 21 and the intermediate core portion 22, and a boundary groove portion 61 is provided at the boundary portion P2 between the intermediate core portion 22 and the rear core portion 23. It is The boundary part P1 and the boundary part P2 are located so that the absorptive core 20 may be crossed in the width direction Y, respectively.
The boundary portion P1 refers to a portion that does not belong to either the front core portion 21 or the intermediate core portion 22, and the boundary portion P2 refers to a portion that does not belong to the rear core portion 23 or the intermediate core portion 22. say the part

The absorbent core 20 is divided into a plurality of blocks by vertical grooves 27, horizontal grooves 28, peripheral grooves 29, and boundary grooves 60 and 61, each of which has a relatively low basis weight of the absorbent member. These grooves are configured to sink downward from the upper surface in the thickness direction (the surface positioned on the wearer's skin side) of the block portion divided into blocks. On the other hand, the block portion is configured to protrude upward in the thickness direction.

In the absorbent core 20, the regions where the grooves are formed, that is, the bottoms forming the grooves, are relatively thinner than the regions of the block portions where the grooves are not formed. The bottom forming the groove has a relatively low basis weight compared to the block, and the bottom of the groove has low rigidity compared to the block. Therefore, when an external force is applied to the absorbent core 20, the absorbent core 20 is easily deformed with the groove as a deformation starting point.
In the following description, the basis weights of the front core portion 21, the intermediate core portion 22 and the rear core portion 23 refer to the basis weights of the block portions excluding the respective groove portions 27, 28, 29, 60 and 61.

The longitudinal grooves 27 extend along the front-rear direction X and are arranged in plurality along the width direction Y at intervals. The vertical groove portion 27 is formed over the entire length in the front-rear direction X so as to divide each of the front core portion 21, the intermediate core portion 22, and the rear core portion 23 in the width direction Y. As shown in FIG.
The lateral grooves 28 extend along the width direction Y and are arranged along the front-rear direction X at intervals. The lateral groove portion 28 is formed over the entire length in the width direction Y so as to divide each of the front core portion 21, the intermediate core portion 22, and the rear core portion 23 in the front-rear direction X. As shown in FIG. In this embodiment, the boundary grooves 60 and 61 formed at the boundaries P1 and P2 are not included in the lateral grooves 28. As shown in FIG. The groove width, which is the length of the boundary grooves 60 and 61 in the front-rear direction X, is wider than that of the lateral grooves 28 .
The peripheral edge groove portion 29 is formed along the front-rear direction X outer edge of the high basis weight portion 4 to be described later.
The configurations such as the shape and arrangement of the vertical grooves 27, the horizontal grooves 28, and the peripheral grooves 29 are not limited to the configuration shown in FIG. set.

Thus, by providing the longitudinal grooves 27, the lateral grooves 28, the peripheral grooves 29, and the boundary grooves 60 and 61, which are low in basis weight and easily deformable, the flexibility of the absorbent core 20 is increased and the wearability is improved. be able to. Further, by providing the grooves, the liquid excreted into the space of the grooves can be quickly drawn into the absorbent core 20, and the liquid absorption rate can be increased. Further, by dividing the absorbent core 20 into a plurality of block portions, the surface area of the absorbent core 20 can be increased, and the liquid can be efficiently absorbed and retained.

(Structure of intermediate core part)
As shown in FIGS. 3 and 4 , the intermediate core portion 22 has a high basis weight portion 4 having a high basis weight of the absorbent member and a low basis weight portion 25 having a lower basis weight than the high basis weight portion 4 . The high basis weight portion 4 has a higher basis weight than the front core portion 21 and the rear core portion 23 .
The high basis weight portion 4 is located in the widthwise central region 65 of the intermediate core portion 22 and extends in the front-rear direction X. As shown in FIG. The low basis weight portions 25 are located extending in the front-rear direction X at both widthwise side regions 66 , 66 of the intermediate core portion 22 . The low basis weight portions 25 extend in the front-rear direction X and are positioned on the left and right so as to face each other along the width direction Y with the high basis weight portion 4 interposed therebetween. The low basis weight portion 25 is located below the upper surface of the high basis weight and high thickness portion 41 . In the absorbent core 20, when an imaginary line parallel to the longitudinal direction X is drawn through the portion where the width direction length of the high basis weight portion 4 is the largest, the inner side of the imaginary line in the width direction Y is the center. area 65 and lateral areas 66 on the outside. The "largest portion of the high basis weight portion 4 in the width direction" is preferably present in the longitudinal center portion of the intermediate core portion 22 in consideration of fit to the wearer's inguinal region.

The high basis weight portion 4 has a high basis weight and high thickness portion 41 and a high basis weight and low thickness portion 42 . The high basis weight and high thickness portion 41 is located in the center portion in the width direction. A pair of high basis weight and low thickness portions 42 are positioned on both sides in the width direction of the high basis weight and high thickness portions 41 so as to face each other along the width direction Y with the high basis weight and high thickness portions 41 interposed therebetween.
The high basis weight high thickness portion 41 and the high basis weight low thickness portion 42 are located in front of and behind the intermediate core portion 22 having the narrowest width in the area where the constricted area 22s along the front-rear direction X of the absorbent core 20 is provided. It is provided extending over the entire length of the direction.
In the napkin 10, in the intermediate core portion 22, the high basis weight high thickness portion 41, the high basis weight low thickness portion 42, the peripheral edge groove portion 29, the low basis weight are symmetrically about the longitudinal groove portion 27c located in the center in the width direction. Part 25 is arranged.
The high basis weight part 4 is arranged so as to face the wearer's excretory part when the napkin 10 is worn.
In FIG. 4 , the low basis weight portion 25 is indicated by a dot pattern with a low density, and the high basis weight portion 4 is indicated by a dot pattern with a higher density than the dot pattern of the low basis weight portion 25 . Furthermore, in the high basis weight portion 4 , the dot pattern density of the high basis weight and low thickness portion 42 is shown to be higher than that of the high basis weight and high thickness portion 41 .

The basis weight of the high basis weight and low thickness portion 42 is equal to the basis weight of the high basis weight and high thickness portion 41 . However, the basis weights of the high basis weight and high thickness part 41 and the high basis weight and low thickness part 42 do not need to be completely the same, and from the viewpoint of absorption performance, the difference between the higher basis weight and the lower basis weight is determined. The value obtained by dividing by the higher basis weight is preferably within 20%, more preferably within 10%. The high grammage low thickness portion 42 has a higher density of the absorbing member than the high grammage high thickness portion 41 and has a high density. The thickness of the high basis weight and low thickness portion 42 is thinner than the high basis weight and high thickness portion 41 and is equivalent to the low basis weight portion 25 . The high basis weight and low thickness portion 42 is positioned between the high basis weight and high thickness portion 41 and the low basis weight portion 25 .
In the intermediate core portion 22, the high basis weight/low thickness portion 42 has the highest rigidity, the high basis weight/high thickness portion 41 has the second highest rigidity, and the low basis weight portion 25 has the lowest rigidity.

As shown in FIG. 3, the high basis weight and high thickness portion 41 of the high basis weight portion 4 is formed thicker than the low basis weight portion 25 and the high basis weight and low thickness portion 42, ). This ensures good fit between the central portion of the intermediate region M2 of the napkin 10 corresponding to the high basis weight and high thickness portion 41 and the wearer's excretory portion.

In this specification, the portion of the absorbent core 20 located outside the high basis weight portion 4 in the width direction Y is referred to as a lateral portion 44 . Therefore, in the present embodiment, the portion of the absorbent core 20 that includes both the low basis weight portion 25 and the straight portion 291 of the peripheral groove portion 29 serves as the side portion 44 . As shown in FIG. 4 , when viewed from above, the side portions 44 have an elongated shape extending in the front-rear direction X, and are positioned to face each other in the width direction Y with the high basis weight portion 4 interposed therebetween. . The pair of side portions 44 are regions that are located on both sides of the high basis weight portion 4 in the width direction Y so as to be in contact with the high basis weight portion 4 and have a lower basis weight than the high basis weight portion 4 .
An intermediate portion in the front-rear direction X of the side portion 44 has a uniform width along the front-rear direction X. As shown in FIG.
The high basis weight portion 4 has a substantially semicircular shape in which the widths of the front portion and the rear portion gradually decrease toward the front core portion 21 and the rear core portion 23, respectively. The part and the rear part are arranged along the high basis weight part 4 having such a substantially semicircular shape. As a result, the widths of the front and rear portions of the side portions 44 gradually increase from the intermediate portion in the front-rear direction X toward the front and rear end portions of the side portions 44 .

Here, a first imaginary straight line along the width direction Y is drawn in the area where the straight line portion 291 of the peripheral groove portion 29 of the absorbent core 20 exists. On the first imaginary straight line, the region where the high basis weight portion 4 is located is the central region 65 in the intermediate core portion 22, and the region where the pair of side portions 44 on both sides of the high basis weight portion 4 are located is the side. area 66; A boundary between the central region 65 and the side regions 66 extends linearly along the front-rear direction X. As shown in FIG.
A second imaginary straight line along the width direction Y is drawn in the region where the curved portion 292 of the peripheral groove portion 29 of the absorbent core 20 exists. On the second virtual straight line, the high basis weight portion 4 and part of the side portion 44 are located in the central region 65, and the boundary between the central region 65 and the side regions 66 is the high basis weight portion 4 and the lateral portion 44.

In this embodiment, as shown in FIG. 3, the width a of the high basis weight high thickness portion 41, the width b of the high basis weight low thickness portion 42, the width c of the low basis weight portion 25, and the width e of the peripheral groove portion 29 are , respectively indicate the width length in the width direction Y of the high basis weight high thickness portion 41, the high basis weight low thickness portion 42, the low basis weight portion 25, and the peripheral edge groove portion 29, which are positioned on the above-described first imaginary straight line. . The width f of the side portion 44 indicates the width length in the width direction Y of the side portion 44 positioned on the above-described first imaginary straight line, and is the width c of the low basis weight portion 25 and the width e of the peripheral edge groove portion 29 . Equivalent to a combination of The constriction covering portion 34 covering the constriction region 22s is positioned on the first imaginary straight line, and the width d of the constriction covering portion 34 indicates the width length in the width direction Y of the constriction covering portion 34 . Note that the width c of the low basis weight portion 25 is the same as the width dimension f of the side portion 44 when the peripheral edge groove portion 29 does not exist.
As shown in FIG. 3 , in the absorbent core 11 of the napkin 10 , the dimension b in the width direction Y of the high basis weight and low thickness portion 42 is smaller than the dimension f in the width direction Y of the lateral portion 44 .

The method of providing the high-density, low-thickness, high-basis-weight portion 42 in the high-basis-weight portion 4 is not particularly limited. For example, as shown in FIG. 5, the high basis weight and low thickness portion 42 can be formed using press working.
As shown in FIG. 5(A) , the intermediate core portion of the absorbent core 20 ′ before press processing includes a high basis weight portion 4 ′ having a high basis weight arranged in the widthwise central region 65 and both sides in the widthwise direction. and a low basis weight portion 25 having a basis weight lower than that of the high basis weight portion 4 ′ arranged in the region 66 .
The absorbent core 20' is covered with a core wrap sheet (not shown), and both rolls of a pressing device comprising a press roll 50 having recesses 53 on a part of the peripheral surface and a flat roll 51 having a smooth peripheral surface. introduced in between. As a result, as shown in FIG. 5B, both sides in the width direction Y of the high basis weight portion 4' are strongly pressed and compressed to form high basis weight and low thickness portions . The distance between the press roll 50 and the flat roll 51 is set so that the low basis weight portions 25 arranged in the side regions 66 are not pressed during pressing. Further, the depth of the recess 53 is set so that the region corresponding to the recess 53 of the press roll 50 in the high basis weight portion 4' is not pressurized.
By locally compressing the high basis weight portion 4 ′ in this way, the high basis weight portion 4 having the high basis weight high thickness portion 41 and the high basis weight low thickness portion 42 is formed.

The intermediate core portion 22 is provided with a peripheral edge groove portion 29, one longitudinal groove portion 27c, and four lateral groove portions 28. As shown in FIG. Here, the vertical groove portion located in the intermediate core portion 22 is referred to as the vertical groove portion 27c in order to distinguish it from the vertical groove portions 27 provided in the other core portions. 27.

As shown in FIG. 4 , the peripheral groove portion 29 as the first groove portion is formed between the high basis weight portion 4 and the low basis weight portion 25 so as to surround at least the periphery of the high basis weight portion 4 in the front-rear direction X. be done. The peripheral groove portion 29 is provided along the side edge of the high basis weight and low thickness portion 42 . The low basis weight portion 25 is provided along the side edge of the high basis weight portion 4 with a peripheral edge groove portion 29 therebetween. The peripheral groove portion 29 has a lower basis weight than the low basis weight portion 25 .
The peripheral groove portion 29 is provided over the front-rear direction X and has a straight portion 291 extending along the front-rear direction X and a curved portion 292 that communicates with the straight portion 291 and curves. The curved portion 292 makes the front end portion 45 and the rear end portion 46 of the high basis weight portion 4 substantially semicircular. It should be noted that the shape is not limited to the semicircular shape, and it is desirable to have a shape capable of dispersing the external force acting within the plane, such as a triangular shape, a trapezoidal shape, or a combination of a circular arc and a straight line.
The peripheral edge groove portion 29 serves as a second groove portion extending along the width direction Y provided at the boundary portion P2 (P1) between the intermediate core portion 22 and the rear core portion 23 (the front core portion 21 and the intermediate core portion 22). is communicated with the boundary groove portion 61 (60).
The rear end portion 46 of the high basis weight portion 4 extending in the front-rear direction X and the boundary groove portion 61 are adjacent to each other, and the front end portion 45 of the high basis weight portion 4 and the boundary groove portion 60 are adjacent to each other.
Further, the high basis weight low thickness portion 42 does not exist at the front end portion and the rear end portion of the high basis weight portion 4 . In the longitudinal region corresponding to the region where the high basis weight low thickness portion 42 of the high basis weight portion 4 in the intermediate core portion 22 does not exist, the width of the low basis weight portion 25 is midway in the longitudinal direction X of the low basis weight portion 25 It gradually increases from the part to the both ends.

The longitudinal groove portion 27c is positioned at the width direction Y center of the intermediate core portion 22, at the width direction Y center of the high basis weight and high thickness portion 41, and at the width direction Y center of each of the front core portion 21 and the rear core portion 23. It is located on the same straight line as the vertical groove portion 27 and communicates with each other.
The four lateral groove portions 28 provided in the intermediate core portion 22 are arranged parallel to each other at equal intervals so as to cross the intermediate core portion 22 along the width direction Y. As shown in FIG. The lateral groove portion 28 is arranged so as to be perpendicular to the linear portion 291 of the peripheral groove portion 29 .

(Configuration of core wrap sheet)
The core wrap sheet 30, as shown in FIG. 34.
The core covering portion includes a front core covering portion 31 covering the front core portion 21 , an intermediate core covering portion 32 covering the intermediate core portion 22 , and a rear core covering portion 33 covering the rear core portion 23 . In FIG. 2, the boundaries between the respective core covering portions 31 to 33 and the constricted covering portion 34 are indicated by dashed lines.

Since the core wrap sheet 30 is made of a sheet material having sufficiently lower rigidity than the absorbent core 20 , the core wrap sheet 30 covers the absorbent core 20 in a shape corresponding to the shape of the absorbent core 20 . For example, as shown in FIG. 3, the intermediate core covering portion 32 deforms into a shape corresponding to the shape of the projecting portion (high basis weight portion 4) of the surface 20a of the intermediate core portion 22. As shown in FIG.

On the other hand, the constriction covering portion 34 is bridged between the front core portion 21 and the rear core portion 23 to extend from the outer edge portion of the intermediate core portion 22 to the constriction region 22s. For this reason, the constriction covering portion 34 is maintained in a shape corresponding to the constriction region 22s in a state in which a constant tension is applied in the front-rear direction X. As shown in FIG.

As shown in FIG. 3, the absorbent member constituting the absorbent core 20 does not exist inside the constricted covering portion 34, but fibers protruding outward from the peripheral edge of the absorbent core 20 and separated from the absorbent core 20 are not present. A portion of the absorbent member may be partially present. 3, the constriction covering portion 34 is drawn to have the same thickness as the low basis weight portion 25 of the absorbent core in the thickness direction Z, but the space in the thickness direction in the absorbent article is There are few and preferably the surface area 341 and the back area 342 are in contact.

[Actions and effects of the present embodiment]
By using the absorbent core 20 having a narrow width of the intermediate core portion 22 and having an overall constricted shape, in the napkin 10, the area including the constricted area 22s in the main body M is wider than the area including the absorbent core 20. It has low stiffness and is soft. Therefore, when worn, the middle region M2 of the napkin 10 is a region that receives an external force directed toward the inner side in the width direction Y from both legs of the wearer on the outer side in the width direction Y, but this region has low rigidity and is soft. Friction between the groin and the napkin 10 is reduced. As a result, it is possible to give the wearer a comfortable feeling of use.

In addition, the absorbent core 20 is provided with a high basis weight portion 4 at the center in the width direction Y in the intermediate core portion 22, and low basis weight portions 25 are provided on both sides thereof.
Then, the high basis weight portion 4 has a high basis weight and high thickness portion 41 in the center in the width direction Y, and is thicker than the high basis weight and high thickness portion 41 between the high basis weight and high thickness portion 41 and the low basis weight portion 25. It has a pair of thin high basis weight low thickness portions 42 . The high basis weight and low thickness portion 42 makes it difficult for the force from the thigh applied to the low basis weight portion 25 to propagate to the high basis weight and high thickness portion 41 . Therefore, the high basis weight and high thickness portion 41 is less likely to be deformed unnecessarily, so that the high basis weight and high thickness portion 41 can be easily brought into close contact with the wearer's excretory part, thereby improving fit. Furthermore, the deformation in the intermediate core portion 22, which is the region facing the excretory portion and its surroundings, causes high rigidity locally, which may cause a strong rubbing sensation with the wearer's skin, but the constriction region 22s Due to the presence of , the deformation of the low basis weight portion 25 and the high basis weight and low thickness portion 42 is also suppressed, so that the feeling of rubbing is reduced.
The configuration of the present invention also has a positive impact on absorption performance. The presence of the high basis weight and low thickness portion 42 makes it difficult for the high basis weight and high thickness portion 41 to deform unnecessarily, thereby making it easier for the high basis weight and high thickness portion 41 to adhere to the wearer's excretory part. Since body fluid discharged from the excretory part can be easily drawn into the absorbent core 20, the high basis weight part 4 can easily retain a large amount of body fluid, and lateral leakage of the body fluid at the constricted part can be suppressed.

In addition, the high basis weight and low thickness portion 42 has a denser structure of the absorbent member than the high basis weight and high thickness portion 41, and is excellent in the ability to extract the liquid. The absorbent core 20 has an action to draw out liquid from the skin surface side, and the force to draw out this liquid is generated by the capillary force of the absorbent core 20, and the capillary force depends on the density of the absorbent members constituting the absorbent core. become stronger in proportion to That is, by providing the high-density, low-thickness portion 42 with a high basis weight, capillary force acts, liquid is easily drawn from the skin surface side, and the drawn liquid is suppressed from reaching the side edges of the absorbent core. be. Moreover, since the deformation of the high basis weight and low thickness portion 42 is also suppressed by the function of the constricted region 22s described above, the bodily fluids held in the high basis weight and low thickness portion 42 flow toward the low basis weight portion 25 side during wearing. Extrusion can also be suppressed.
Furthermore, since the compressed high-density, high basis weight, and low thickness portion 42 is provided to extend over the entire length of the narrow intermediate core portion 22 in the front-rear direction X, the high basis weight, low thickness portion 42 is provided. The diffusion direction of the liquid is guided so that the liquid absorbed in 42 diffuses in the front-rear direction X, and side leakage is further suppressed. Thus, even if the width of the intermediate core portion 22, which is the portion facing the excretion portion, is narrow, side leakage is suppressed by providing the high-density, low-thickness portion 42 with a high basis weight.

In addition, when the absorber 11 is worn, when it receives an external force directed toward the inner side in the width direction Y from both legs of the wearer on the outer side in the width direction Y, the absorber 11 typically corresponds to the constricted region 22s as shown in FIG. The constriction covered portion 34 having low rigidity where the absorbent core 20 does not exist deforms first, and then the low basis weight portion 25 deforms.
By providing the absorbent core with the constricted region 22s in this manner, the external force applied to the intermediate core portion 22 during wearing is reduced compared to the case of using an absorbent core having a uniform width in the front-rear direction X and having no constricted region. can be reduced by Thereby, the deformation of the intermediate core portion 22 is suppressed, and the occurrence of liquid leakage due to the deformation is suppressed. In addition, since deformation of the intermediate core portion 22 is suppressed, deformation of the rear core portion due to propagation of deformation of the intermediate core portion to the rear core portion is also suppressed, so liquid leakage due to deformation of the rear core portion is suppressed. is suppressed.

In the napkin 10 , the high basis weight and high thickness portion 41 is formed over the entire length of the intermediate core portion 22 so as to protrude toward the skin. Thereby, when the napkin 1 is worn, it is possible to ensure a good fit between the high basis weight and high thickness portion 41 and the excretion portion.

As described above, the absorbent article of the present embodiment reduces friction between the groin and the napkin, and can provide the wearer with a comfortable feeling of use with reduced stiffness. It has a good fit and excellent liquid absorption performance that prevents side leakage.

Moreover, as shown in FIG. 3, in the napkin 10, the width b in the width direction Y of the high basis weight and low thickness portion 42 is preferably smaller than the width f of the lateral portion. Moreover, the dimension b in the width direction Y of the high basis weight and low thickness portion 42 is preferably smaller than the width c of the low basis weight portion 25 . These relationships need only be satisfied by half the length of the entire length in the front-rear direction X of the intermediate core portion 22, but are preferably satisfied by the portion in the front-rear direction X where the side regions 66 are present. Furthermore, it is preferable to fill the entire length of the intermediate core portion 22 in the front-rear direction X.
As a result, the proportion of the high basis weight and low thickness portion 42, which has the highest rigidity in the intermediate core portion 22, in the width direction Y of the intermediate core portion 22 can be relatively reduced, and the wearer's skin and the napkin 1 can be kept in contact with each other. Friction with can be reduced. In addition, by making the width b smaller than at least one of the width c and the width f, the length from the side edge of the intermediate core portion 22 in the width direction Y to the high-rigidity high-basis-weight, low-thickness portion 42 is increased. can take That is, since the width of the side portion 44, preferably the side region 66, which has low rigidity can be widened, the rubbing between the groin and the napkin 1 during wearing is reduced.

In addition, along the side edge of the high basis weight and low thickness portion 42, between the high basis weight and low thickness portion 42 and the low basis weight portion 25, a peripheral edge groove portion 29 having a low basis weight is provided, so that the intermediate core portion 22 more flexibility. As a result, when the napkin 1 comes into contact with the wearer's skin during wearing, the absorbent core 20 changes flexibly, and friction at the groin is alleviated.
In addition, by providing the peripheral groove portion 29 that is easier to deform due to the lower basis weight than the low basis weight portion 25 , the deformation around the high basis weight portion 4 is absorbed by the peripheral groove portion 29 , so that the low basis weight portion 25 is deformed. is less likely to be transmitted to the high basis weight portion 4. That is, the external force received from both the left and right legs when worn is relieved by the peripheral edge grooves 29, and the external force propagated to the high basis weight portion 4 is further reduced. Therefore, deformation of the high basis weight portion 4 is suppressed, and liquid leakage is suppressed.

In addition, since the boundary grooves 60 and 61 are provided, the boundary grooves 60 and 61 become bending points when the napkin 1 is worn, and the napkin 1 can be easily bent in the front-rear direction X and easily deformed along the wearer's body. Also, the curved portion 292 of the peripheral groove portion 29 arranged in the front-rear direction X becomes a bending point when the napkin 1 is worn, and the napkin 1 is easily bent and deformed along the wearer's body. As a result, the fit is improved, the friction is reduced, and the gap between the skin and the napkin 1 is reduced, thereby suppressing liquid leakage.
In addition, since the peripheral groove portion 29 and the boundary groove portion 61 (60) communicate with each other, the external force acting on the intermediate core portion 22 passes through the peripheral groove portion 29 and is further relieved by the boundary groove portion 61 (60). Deformation at portion 22 is less likely to propagate to rear core portion 23 (front core portion 21).
In addition, since the deformation occurring in each of the front core portion 21 and the rear core portion 23 is mitigated by the boundary grooves 60 and 61 and is less likely to propagate to the intermediate core portion 22, deformation in the high basis weight portion 4 is effectively suppressed. be able to.

In addition, by providing the intermediate core portion 22 with the lateral groove portion 28 and the peripheral edge groove portion 29, the low basis weight portion 25 is partitioned into a plurality of blocks, and a certain effect of confining the deformation region in block units can be obtained. As a result, the propagation of the external force to the high basis weight portion 4 is suppressed, and the effect of preventing deformation of the high basis weight portion 4 can be further enhanced.

Further, as shown in FIG. 4, the low basis weight portion 25 of the intermediate core portion 22 does not have the vertical groove portion 27 having a lower basis weight than the block portion. In other words, the longitudinal groove portion 27 dividing the low basis weight portion 25 in the width direction Y does not exist in the low basis weight portion 25 of the intermediate core portion 22 . The longitudinal grooves 27 of the front core portion and the longitudinal grooves 27 of the rear core portion are present in front and rear of the low basis weight portion 25, respectively. With this configuration, while maintaining the absorption capacity of the low basis weight portion 25 of the intermediate core portion 22, the vertical groove portion 27 of the front and rear core portions allows the load from the inguinal region to escape to the front and rear core portions, thereby enabling the high basis weight portion. Unexpected deformation of 4 can be further suppressed.

Further, as shown in FIG. 4 , when the width of the high basis weight portion 4 is gradually narrowed in the front and rear direction, the force applied from the thigh to the low basis weight portion 25 is applied to the intermediate core portion 22 in the front and rear direction. It becomes easier to escape to the part. Therefore, even if an abnormally strong force is applied to the intermediate core portion 22, deformation of the intermediate core portion 22 can be easily suppressed. Furthermore, in the high basis weight portion 4, if the high basis weight and low thickness portion 42 does not exist at the front end and the rear end portion, and only the high basis weight and high thickness portion 41 exists, the width of the low basis weight portion 25 is However, since it gradually increases from the intermediate portion in the front-rear direction X of the low basis weight portion 25 toward both end portions, the effect can be obtained more easily.

[Additional description of this embodiment]
The description of this embodiment will be supplemented below.
Numerical examples of each configuration will be described, but these numerical values are examples and are not limited to the numerical values described here.
(Numerical examples for each configuration)
In the case of a sanitary napkin, the widths D1 and D3 of the front core portion 21 and the rear core portion 23 are preferably 60 mm or more, more preferably 70 mm or more, and preferably 100 mm or less, more preferably 90 mm. It is below.
The thickness of the front core portion 21 and the rear core portion 23 is preferably 1.5 mm or more, more preferably 2 mm or more, and preferably 6 mm or less, further preferably 5.5 mm or less. The basis weight of the front core portion 21 and the rear core portion 23 is preferably 90 g/m ² or more, more preferably 100 g/m ² or more, and preferably 350 g/m ² or less, further preferably 300 g/m ² or less.
The width D2 of the intermediate core portion 22 is typically formed larger than the crotch width of a general wearer (about 30 mm), preferably 35 mm or more, more preferably 40 mm or more, and preferably It is 75 mm or less, more preferably 70 mm or less. As a result, it is less likely to be affected by an external force directed inward in the width direction Y applied by the wearer's legs, etc., and it is possible to cope with the displacement of the wearing position in the width direction Y, giving the wearer a sense of security. be able to.
The length of the intermediate core portion 22 in the front-rear direction X is, for example, preferably 60 mm or more, more preferably 80 mm or more, and preferably 180 mm or less, more preferably 170 mm or less. As a result, even if there is a deviation in the mounting position in the front-rear direction X, the intermediate core portion 22 can be made to face the wearer's excretory portion.

Hereinafter, the width of the high basis weight portion 4, the width of the high basis weight and high thickness portion 41, the width of the high basis weight and low thickness portion 42, and the width of the low basis weight portion 25 are defined by the width of the high basis weight portion 4 in the front-back direction. is not uniform, it is the width at the point where a virtual line is drawn in the width direction Y in the widest portion of the high basis weight portion 4 .
The width of the high basis weight portion 4 arranged in the central region in the width direction of the intermediate core portion 22 is preferably 15 mm or more, more preferably 20 mm or more, and preferably 60 mm or less, further preferably 50 mm. It is below. By setting the width in such a range, a sufficient amount of absorption can be ensured.
The high grammage portion 4 has a high grammage low thickness portion 42 whose thickness is locally reduced by compressing both sides thereof. By reducing the thickness in this way, the feeling of stiffness when worn is reduced.
As shown in FIG. 3, the width a of the high basis weight and high thickness portion 41 is preferably 10 mm or more, more preferably 15 mm or more, and preferably 40 mm or less, further preferably 30 mm or less. . By setting the width of the high-basis-weight, high-thickness portion 41, which is the projecting portion of the absorbent core 22, within such a range, it is possible to enhance the fit to the wearer's excretory portion.
From the viewpoint of diffusing the absorbed liquid in the front-rear direction X while suppressing the occurrence of rubbing, the width b of the high basis weight and low thickness portion 42 is preferably 2 mm or more, more preferably 3 mm or more, and , preferably 10 mm or less, more preferably 7.5 mm or less.
Further, it is preferable that the width f of the side portion 44 is wider than the width b of the high basis weight and low thickness portion 42, because the rubbing of the napkin 10 on the groin is further suppressed. The width f of the lateral portion 44 is preferably 10 mm or more, more preferably 12 mm or more. And it is preferably 30 mm or less, more preferably 25 mm or less. The width c of the low basis weight portion 25 is preferably 5 mm or more, more preferably 7.5 mm or more. The width c of the low basis weight portion 25 is preferably 30 mm or less, more preferably 20 mm or less.
The width f of the side portion 44 is preferably 2 times or more, more preferably 2.5 times or more, and preferably 5 times or less, the width b of the high basis weight low thickness portion 42, More preferably, it is 4 times or less.
Moreover, it is preferable that the dimension b in the width direction Y of the high basis weight and low thickness portion 42 is smaller than the dimension d in the width direction Y of the constriction covering portion 34 . The width d of the constriction covering portion 34 is preferably 5 mm or more, more preferably 10 mm or more, and preferably 30 mm or less, further preferably 20 mm or less.

The basis weight of the high basis weight portion 4 is preferably 250 g/m ² or more, more preferably 300 g/m ² or more, and more preferably 700 g/m ² from the viewpoint of ensuring a sufficient liquid absorption capacity. or less, more preferably 650 g/m ² or less.
The basis weight of the low basis weight portion 25 is preferably 90 g/m ² or more, more preferably 100 g/m ² or more, and more preferably 100 g/m 2 or more, from the viewpoint of reducing rigidity while maintaining appropriate liquid absorbency. is 350 g/m ² or less, more preferably 300 g/m ² or less.

The thickness of the high basis weight and high thickness portion 41 is preferably 2 mm or more, more preferably 2.5 mm or more, and preferably 9 mm or less, further preferably 8 mm or less.
The thickness of the high basis weight low thickness portion 42 and the low basis weight portion 25 is preferably 1.5 mm or more, more preferably 2 mm or more, and preferably 6 mm or less from the viewpoint of reducing stiffness, More preferably, it is 5.5 mm or less.
The difference in thickness between the high basis weight high thickness portion 41 and the high basis weight low thickness portion 42 is preferably 0.5 mm or more, from the viewpoint of the fit of the high basis weight high thickness portion 41 to the excretion part, It is preferably 1 mm or more, preferably 5 mm or less, more preferably 4 mm or less.

The density of the high basis weight and high thickness portion 41 is preferably 0.073 g/cm ³ or more, more preferably 0.091 g/cm ³ or more, and preferably 0.182 g/cm ³ or less, More preferably, it is 0.164 g/cm ³ or less.
The density of the high basis weight and low thickness portion 42 is preferably 0.114 g/cm ³ or more, more preferably 0.143 g/cm ³ or more, and preferably 0.286 g/cm ³ or less, More preferably, it is 0.257 g/cm ³ or less.
The density of the high basis weight, low thickness portion 42 is preferably 1.6 times or more, more preferably 1.4 times or more, and preferably 2.4 times or less that of the high basis weight, high thickness portion 41. and more preferably 2.2 times or less.

The widths of the peripheral grooves 29, the vertical grooves 27 and the lateral grooves 28 are preferably 0.5 mm or more, more preferably 1 mm or more, and preferably 10 mm or less, more preferably 5 mm or less.
Arranged at the boundary between the intermediate core portion 22 and the rear core portion 23 (front core portion 21), in other words, between the high basis weight portion 4 and the rear core portion 23 (front core portion 21) in the width direction Y The width of the boundary grooves 61 (60) arranged to extend is preferably 1.5 mm or more, more preferably 2 mm or more, and preferably 3.5 mm or less, more preferably 3 mm or less.
The basis weight of the peripheral grooves 29, the longitudinal grooves 27 and the lateral grooves 28 is lower than that of the block parts, preferably 50 g/m ² or more, and preferably 250 g/m ² or less.

The numerical values in each of the configurations described above can be measured by the following measuring methods.
(Method for measuring the width of each part of the absorbent core)
The width of the absorbent core portion, the high basis weight high thickness portion, the high basis weight low thickness portion, the low basis weight portion, and the width of the lateral outside were measured by placing the absorbent core horizontally and using a microscope (KEYENCE VHX-1000 ) to adjust the measurement magnification and enlarge the skin-facing surface 20a to measure the width.

(Method for measuring the basis weight of each part of the absorbent core)
Each portion of the absorbent core 20 to be measured is cut using a single-edged razor manufactured by Feather to obtain a small piece having a predetermined area. The weights of these small pieces are measured using an electronic balance (A&D electronic balance GR-300, precision: 4 digits below the decimal point). The basis weight of the small piece is calculated by dividing the obtained weight by the area of the small piece of each part. The basis weight of each part is the average of the basis weights of the five small pieces.

(Measuring method of density in high basis weight and high thickness part and high basis weight and low thickness part)
The density is calculated by dividing the basis weight obtained in the same manner as the basis weight measurement method described above by the thickness of the piece to be measured.
The thickness of the small piece to be measured is measured by measuring the thickness of the small piece cut out to measure the basis weight described above. A circular aluminum plate with a diameter of 25 mm, a thickness of 3 mm, and a mass of 2.45 g is placed horizontally and gently on the measurement surface of a small piece cut out from the absorbent core, and a non-contact laser displacement meter (laser head LK-G30, displacement gauge LK-GD500) is used to measure the thickness of the sample. When the size of the cut piece is small and it is difficult to measure with a non-contact laser displacement meter, the cross section of the cut sample is measured at 20 to 100 using a microscope (VHX-1000 manufactured by KEYENCE). It may be observed and measured at double magnification.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

For example, in the above-described embodiment, the high basis weight portion 4 protrudes upward in the thickness direction Z, but instead of this, it protrudes downward in the thickness direction Z like an absorber 24 shown in FIG. may be in the form Further, in the above-described embodiment, various grooves such as the vertical grooves 27, the horizontal grooves 28, the peripheral grooves 29, and the boundary grooves 60 and 61 provided in the absorbent core 20 have openings on the upper side in the thickness direction Z. Alternatively, an absorbent body 24 shown in FIG. 6 having an opening on the lower side in the thickness direction Z may be used.

Moreover, in the above-described embodiments, an example of a sanitary napkin is shown as an absorbent article, but it is not limited to this. The absorbent article of the present invention may be, for example, an incontinence pad or a pantyhose sheet.

EXAMPLES The present invention will be further described below using examples, but the present invention is not limited to these examples.

(1)
An absorbent article comprising an absorbent core having a front core portion and a rear core portion positioned at both ends in a front-rear direction, and an intermediate core portion positioned between the front core portion and the rear core portion, , the intermediate core portion has a length in a width direction orthogonal to the front-rear direction shorter than the front core portion and the rear core portion, the intermediate core portion is located in a width direction center region, and the front core portion and a high basis weight portion having a higher basis weight than the rear core portion, and a low basis weight portion located in both width direction side regions and having a lower basis weight than the high basis weight portion, and the high basis weight portion The weight portion includes a high basis weight and high thickness portion located in the center in the width direction, and a high basis weight and low thickness portion that is thinner than the high basis weight and high thickness portion located on both sides in the width direction of the high basis weight and high thickness portion. and a pad-type absorbent article.
(2)
The pad-type absorbent article according to (1), wherein the dimension in the width direction of the low basis weight portion is larger than the dimension in the width direction of the high basis weight and low thickness portion.
(3)
The pad-type absorbent article according to (1) or (2), wherein the high basis weight and low thickness portion is arranged over the entire length of the intermediate core in the front-rear direction.
(4)
(1), wherein the intermediate core portion has a first groove portion having a lower basis weight than the low basis weight portion in the front-rear direction between the high basis weight and low thickness portion and the low basis weight portion; The pad-type absorbent article according to any one of (3) to (3).
(5)
Any one of (1) to (4) above, wherein the absorbent core has a second groove portion having a lower basis weight than the low basis weight portion at a boundary between the intermediate core portion and the rear core portion. The pad-type absorbent article according to 1.
(6)
Any one of (1) to (5) above, wherein the absorbent core has a second groove portion having a lower basis weight than the low basis weight portion at a boundary between the front core portion and the intermediate core portion. The pad-type absorbent article according to 1.
(7)
The intermediate core portion has a first groove portion having a lower basis weight than the low basis weight portion extending in the front-rear direction between the high basis weight and low thickness portion and the low basis weight portion,
The pad-type absorbent article according to (5) or (6), wherein the second groove communicates with the first groove.
(8)
The pad-type absorbent article according to any one of (1) to (7), wherein the front core portion has a tapered portion at the rear end, and the rear core portion has a tapered portion at the front end.
(9)
any one of (1) to (8) above, wherein the front core portion, the intermediate core portion, and the rear core portion have longitudinal grooves extending in the front-rear direction and lateral grooves extending in the width direction; The pad-type absorbent article described.
(10)
The basis weight of the high basis weight and low thickness portion and the basis weight of the high basis weight and high thickness portion are 20, which is the difference between the higher basis weight and the lower basis weight divided by the higher basis weight. %, more preferably within 10%, the pad-type absorbent article according to any one of (1) to (9).
(11)
The front core portion has a tapered portion at a rear end, the rear core portion has a tapered portion at a front end, and the tapered portions each decrease in width toward the intermediate core portion. ) to (10), the pad-type absorbent article.
(12)
The intermediate core portion is formed between a pair of constricted regions located in the front-rear direction intermediate portion of the absorbent core,
The absorbent core is covered with a core wrap sheet, and the core wrap sheet is bridged between the front core section and the rear core section outside the side edges of the intermediate core section in the width direction. Thus, the pad-type absorbent article according to any one of (1) to (11) above, which has a constriction covering portion extending from the outer edge of the intermediate core portion to the constriction region.
(13)
The pad-type absorbent article according to (11) above, wherein no absorbent member constituting the absorbent core is present inside the constriction covering portion.
(14)
The pad-type absorbent article according to (11) or (12), wherein the dimension in the width direction of the high basis weight and low thickness portion is smaller than the dimension in the width direction of the constriction covering portion.
(15)
The low basis weight portion of the intermediate core portion does not have a vertical groove portion that divides the low basis weight portion in the width direction, and the front core portion and the rear core portion are respectively forward and backward of the low basis weight portion. The pad-type absorbent article according to any one of (1) to (14) above, which has longitudinal grooves at the rear.
(16)
The pad-type absorbent article according to any one of (1) to (15), wherein the width of the high basis weight portion gradually decreases in the front portion and the rear portion.
(17)
The high basis weight low thickness portion does not exist at the front end portion and the rear end portion of the high basis weight portion, and in the front-rear region of the intermediate core portion, the width of the low basis weight portion is the same as that of the low basis weight portion. The pad-type absorbent article according to any one of (1) to (16) above, which gradually increases from the intermediate portion side in the front-rear direction toward both end portions.
(18)
The density of the high basis weight and high thickness portion is 0.073 g/cm ³ or more, more preferably 0.091 g/cm ³ or more, and preferably 0.182 g/cm ³ or less, further preferably is 0.164 g/cm ³ or less , the pad-type absorbent article according to any one of (1) to (17).
(19)
The density of the high basis weight and low thickness portion is preferably 0.114 g/cm ³ or more, more preferably 0.143 g/cm ³ or more, and preferably 0.286 g/cm ³ or less, The pad-type absorbent article according to any one of (1) to (18) above, which is more preferably 0.257 g/cm ³ or less .
(20)
The pad-type absorbent article according to any one of (1) to (19) above, wherein the pad-type absorbent article is a sanitary napkin.
(21)
The width of the front core portion and the rear core portion is preferably 60 mm or more, more preferably 70 mm or more, and preferably 100 mm or less, and further preferably 90 mm or less, from (1) above The pad-type absorbent article according to any one of (20).
(22)
The thickness of the front core portion and the rear core portion is preferably 2 mm or more, more preferably 2.5 mm or more, and preferably 7 mm or less, further preferably 6 mm or less. ) to (21), the pad-type absorbent article.
(23)
The basis weight of the front core portion and the rear core portion is preferably 90 g/m ² or more, more preferably 100 g/m ² or more, and preferably 300 g/m ² or less, further preferably The pad-type absorbent article according to any one of (1) to (22) above, which is 250 g/m ² or less.
(24)
Any of (1) to (23) above, wherein the width of the intermediate core portion is preferably 35 mm or more, more preferably 40 mm or more, and preferably 75 mm or less, further preferably 70 mm or less. or a pad-type absorbent article according to any one of the above.
(25)
The length of the intermediate core portion in the front-rear direction is preferably 60 mm or more, more preferably 80 mm or more, and is preferably 180 mm or less, further preferably 170 mm or less, (1) to (24) Pad type absorbent article according to any one of.
(26)
The width of the high basis weight and low thickness portion is preferably 2 mm or more, more preferably 3 mm or more, and preferably 10 mm or less, further preferably 7.5 mm or less, from (1) above (25) The pad-type absorbent article according to any one of (25).
(27)
The intermediate core portion has a pair of side portions including the low basis weight portion located on both sides in the width direction of the high basis weight portion,
The width of the side portion is preferably 2 times or more, more preferably 2.5 times or more, and preferably 5 times or less, and more preferably the width of the high basis weight and low thickness portion. is 4 times or less, the pad-type absorbent article according to any one of the above (1) to (26).

[Example 1]
A sanitary napkin having the same basic configuration as the napkin 10 shown in FIGS. 1 to 4 was produced. An air-through nonwoven fabric with a basis weight of 74 g/m ² is used as the top sheet 12, a non-moisture-permeable polyethylene film sheet with a basis weight of 25 g/m ² is used as the back sheet, and a water-repellent spun fabric with a basis weight of 20 g/m ² is used as the side sheet. A bonded nonwoven fabric was used.
In the absorbent core, the intermediate core portion 22 has a width of 65 mm and a dimension in the front-back direction X of 90 mm, the front core portion 21 has a width of 72 mm and a dimension in the front-back direction X of 23 mm, and the rear core portion 23 has a width of 72 mm and a dimension in the front-back direction X. was 82 mm, and the shape of the constricted shape shown in FIG. 4 was used.
The absorbent core was provided with a plurality of lateral grooves, vertical grooves, peripheral grooves, and boundary grooves in the same manner as the embodiment shown in FIG. The basis weight of these grooves was 75 g/m ² , and the thickness of the bottom forming the grooves was 2 mm.
The width a of the high basis weight and high thickness portion 41 was 20 mm, and the width b of the high basis weight and low thickness portion 42 was 5 mm. The width c of the low basis weight portion 25 was 16 mm. The groove width of the peripheral edge groove portion 29 and the vertical groove portion 27c provided in the intermediate core portion 22 was 1.5 mm.
Five vertical grooves 27 are provided in the front core portion 21 and the rear core portion 23, and the width of the three vertical grooves 27 located in the central portion is 4 mm. The width of each longitudinal groove was 1.5 mm. The dimensions in the width direction of the block portions provided in the front core portion 21 and the rear core portion 23 were the same width.
In the absorbent core 20, the lateral groove portion 28 had a groove width (dimension in the front-rear direction X) of 2 mm. The groove width of the boundary grooves 60 and 61 was 2.5 mm.
The basis weight of the front core portion 21 and the rear core portion 23 was 200 g/m ² and the thickness was 3.5 mm. In the intermediate core portion 22, the basis weight of the low basis weight portion 25 was 200 g/m ² , the thickness was 3.5 mm, and the basis weight of the high basis weight portion 4 was 440 g/m ² . By locally compressing the high basis weight portion 4, a high basis weight and high thickness portion 41 and a high basis weight and low thickness portion 42 are provided. The thickness of the high basis weight, high thickness portion 41 was 5.5 mm, and the thickness of the high basis weight, low thickness portion 42 was 3.5 mm. The density of the high basis weight, high thickness portion 41 was 0.080 g/m ³ , and the density of the high basis weight, low thickness portion 42 was 0.126 g/m ³ .
The absorbent core of the above form is covered with a core wrap sheet to form an absorbent body, the absorbent body is sandwiched between the top sheet and the back sheet, and side sheets are provided to form the napkin of Example 1. did. An adhesive was used to bond between the absorbent core and the topsheet, between the absorbent core and the backsheet, between the sidesheet and the topsheet, and between the topsheet and the backsheet.

[Example 2]
Compared with Example 1, the basis weight of the high basis weight portion 4 of the intermediate core portion 22, the thickness and density of the high basis weight and high thickness portion 41, the thickness and density of the high basis weight and low thickness portion 42, and the front and rear A constricted napkin having a configuration similar to that of Example 1 except that the width of the core portion was different was produced.
In the napkin in Example 2, the basis weight of the high basis weight portion 4 was 550 g/m ² . The high basis weight/high thickness portion 41 had a thickness of 7.0 mm and a density of 0.079 g/m ³ , and the high basis weight/low thickness portion 42 had a thickness of 3.5 mm and a density of 0.157 g/m ³ .
In the absorbent core, the width of the intermediate core portion 22 is 65 mm and the dimension in the front-rear direction X is 130 mm, the width of the front core portion 21 is 80 mm and the dimension in the front-rear direction X is 36 mm, and the width of the rear core portion 23 is 80 mm in the front-rear direction. The constriction-shaped form shown in FIG. 4 was used, with the dimension of X being 137 mm.

[Comparative example]
FIG. 7 corresponds to the absorbent core described in Patent Document 2 mentioned above. The absorbent core shown in FIG. 7 and the absorbent core described in Patent Document 2 have different basic configurations in terms of the number of blocks, but the width is uniform in the front-rear direction X without constriction, and partly compressed. They are common in that the high basis weight portion is located in the intermediate core portion.
The shape of the high basis weight portion 4 of the absorbent core 70 shown in FIG. 7 is an oval shape in which the front end portion and the rear end portion of the high basis weight portion 4 in the above-described embodiment are substantially semicircular. A comparative napkin was produced in the same manner as the napkin of Example 1, except that the absorbent core was used to produce a sanitary napkin. Unlike the absorbent cores of Examples 1 and 2 having constrictions, the absorbent core 70 having the configuration shown in FIG. In FIG. 7, the same reference numerals are given to the same components as those of the absorbent core described above.
The absorbent core 70 is provided with a plurality of lateral grooves 28 , vertical grooves 27 , peripheral grooves 29 and boundary grooves 60 and 61 . The grammage and thickness of these grooves are the same as in Examples 1 and 2. In the absorbent core 70, the groove widths of the longitudinal grooves 27 and the peripheral grooves 29 are both 1.5 mm. The groove width of the boundary groove portions 60 and 61 was 2 mm, which is the same as that of the lateral groove portion 28 .
The three vertical grooves 27 formed in the intermediate core portion 22 are located on the same straight line as the five vertical grooves 27 respectively located in the front core portion 21 and the rear core portion 23 .
The widthwise dimension of each block portion 71 provided in the intermediate core portion 21 and the rear core portion 23 was the same width.
The basis weight and thickness of the high basis weight portion 4 and the low basis weight portion 25 , the thickness, density and width of the high basis weight and high thickness portion 41 and the high basis weight and low thickness portion 42 were the same as in the first embodiment.

[evaluation]
The napkins of Examples 1 and 2 and the napkins of Comparative Examples were evaluated according to the following evaluation criteria in terms of absorbency and rubbing, and the evaluation results are shown in Table 1.
(Absorbability evaluation method)
A sanitary napkin to be evaluated was fixed to sanitary shorts and attached to a dynamic model of the lower body of the human body. As a dynamic model of the human body, we used a movable female waist model that can walk both legs. The walking motion of the dynamic model was started, and 1 minute after the start of the walking motion, 2 g of simulated blood was injected from the fluid excretion point (first time). Furthermore, 3 g of simulated blood was injected 3 minutes after the end of the first fluid injection (second injection). Furthermore, 2 g of simulated blood was injected 3 minutes after the end of the second fluid injection (third injection). From the third time onwards, the operation of injecting 2 g of simulated blood 3 minutes after the injection of the liquid is repeated, and the injection of the liquid is finished when the simulated blood oozes out from the wings of the sanitary napkin. The total weight of the simulated blood was taken as the maximum dynamic absorption.
The simulated blood was measured using a B-type viscometer (manufactured by Toki Sangyo Co., Ltd., model number TVB-10M, measurement conditions: rotor No. 19, 30 rpm, 25 ° C., 60 seconds) so that the viscosity was 8 mPa s. , defibrinated horse blood (manufactured by Nihon Biotest Laboratory Co., Ltd.) with a adjusted blood cell/plasma ratio was used.

(Rubbing evaluation method)
A sanitary napkin to be evaluated was fixed to sanitary shorts and attached to a dynamic model of the human body. As a dynamic model of the human body, we used a movable female waist model that can walk both legs. A 3-axis tactile sensor (Touchence Co., Ltd., Shokaku Chip TS type) was placed on the groin of the dynamic model, and rubbing against the napkin on the groin was measured for 1 minute after starting the walking motion. After 1 minute, the walking motion was terminated, and the maximum shear force during walking was defined as the amount of rubbing. The smaller the maximum shear force, the smaller the friction with the napkin in the inguinal region.

As shown in Table 1, good absorption characteristics can be obtained even if the width of the intermediate core portion is narrowed by providing constrictions, and that the provision of constrictions reduces rubbing.

DESCRIPTION OF SYMBOLS 1... Pad-type absorbent article 4... High basis weight part 10... Napkin 11, 24... Absorbent body 20... Absorbent core 21... Front core part 22... Intermediate core part 23... Rear core part 25... Low basis weight part 41... High basis weight and high thickness portion 42 High basis weight and low thickness portion 65 Central region 66 Side regions

Claims (4)

A pad-type absorbent article comprising an absorbent core having a front core portion and a rear core portion positioned at both ends in a front-rear direction, and an intermediate core portion positioned between the front core portion and the rear core portion. There is
the intermediate core portion has a length in a width direction perpendicular to the front-rear direction shorter than the front core portion and the rear core portion;
The intermediate core portion includes a high basis weight portion located in the widthwise central region and having a higher basis weight than the front core portion and the rear core portion, and a high basis weight portion located in both widthwise side regions and having a basis weight higher than the high basis weight portion. a low basis weight portion having a low basis weight;
The high basis weight portion is thinner than the high basis weight and high thickness portion located in the center in the width direction and the high basis weight and high thickness portion located on both sides in the width direction of the high basis weight and high thickness portion , a high basis weight and low thickness portion having a higher density than the high basis weight and high thickness portion;
The intermediate core portion has a first groove portion having a lower basis weight than the low basis weight portion extending in the front-rear direction between the high basis weight and low thickness portion and the low basis weight portion,
The intermediate core portion is formed between a pair of constricted regions located in the front-rear direction intermediate portion of the absorbent core,
The absorbent core is covered with a core wrap sheet, and the core wrap sheet is bridged between the front core section and the rear core section outside the side edges of the intermediate core section in the width direction. so that it has a constriction covering portion extending from the outer edge of the intermediate core portion to the constriction region,
In the low basis weight portion of the intermediate core portion, there is no vertical groove portion having a lower basis weight than the low basis weight portion dividing the low basis weight portion in the width direction,
The front core portion and the rear core portion respectively have longitudinal grooves in front and rear of the low basis weight portion.
Pad type absorbent article. The pad-type absorbent article according to claim 1, wherein the dimension in the width direction of the low basis weight portion is larger than the dimension in the width direction of the high basis weight and low thickness portion. The pad-type absorbent article according to claim 1 or 2, wherein the high basis weight and low thickness portion is arranged over the entire length of the intermediate core in the front-rear direction. The absorbent core has, at the boundary between the intermediate core portion and the rear core portion, a second groove portion having a basis weight lower than that of the low basis weight portion and communicating with the first groove portion. The pad-type absorbent article according to claim 3 .

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