CN112153953B

CN112153953B - Pad type absorbent article

Info

Publication number: CN112153953B
Application number: CN201980033770.7A
Authority: CN
Inventors: 阿部雅义; 松井学
Original assignee: Kao Corp
Current assignee: Kao Corp
Priority date: 2018-09-04
Filing date: 2019-09-02
Publication date: 2022-03-15
Anticipated expiration: 2039-09-02
Also published as: TWI819085B; TW202023507A; JP7125310B2; CN112153953A; WO2020050219A1; JP2020036743A

Abstract

A pad-type absorbent article according to one aspect of the present invention includes an absorbent core having a front core portion and a rear core portion located on both end portions in a 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 length of the intermediate core portion in the width direction orthogonal to the front-rear direction is shorter than the length of the front core portion and the length of the rear core portion. The intermediate core portion includes: a high grammage portion located in a widthwise central region and having a higher grammage than the front core portion and the rear core portion; and low grammage parts located in both widthwise side regions and having a grammage lower than that of the high grammage part. The high grammage part includes: a high-grammage and high-thickness portion located at a widthwise central portion; and a high-grammage low-thickness portion which is located on both sides in the width direction of the high-grammage high-thickness portion and is thinner than the high-grammage high-thickness portion.

Description

Pad type absorbent article

Technical Field

The present invention relates to a pad-type absorbent article such as a sanitary napkin for menstrual period.

Background

In a disposable diaper requiring a high absorption capacity, a design is generally performed to increase the total amount of absorbent materials contained in the absorbent body. Since the absorbent body is hard when the total amount of the absorbent material is large, a technique is employed in which the absorbent body is formed in a shape that is retracted along the circumference of the legs in the crotch of the wearer, thereby reducing the feeling of wearing discomfort (for example, patent document 1).

On the other hand, a so-called pad-type absorbent article of a type that is used by being disposed inside underwear such as a sanitary napkin usually requires a smaller absorption capacity than diaper, and therefore the absorbent body does not become as hard as diaper, and a rectangular absorbent body is often used. For example, patent document 2 discloses an absorbent core having a shape with an equal width in the front-rear direction. In order to prevent side leakage, the absorbent core is provided with a V-shaped opening on the skin surface of a projecting portion disposed at the center in the width direction of the absorbent core facing the excretory part of the wearer, and has high-density portions on both sides of the projecting portion.

Documents of the prior art

Patent document

Patent document 1: japanese patent application laid-open No. 2010-131206

Patent document 2: japanese patent laid-open No. 2015-112235

Disclosure of Invention

A pad-type absorbent article according to one aspect of the present invention includes an absorbent core having front and rear core portions positioned on both end portions in a 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 length of the intermediate core portion in the width direction orthogonal to the front-rear direction is shorter than the length of the front core portion and the length of the rear core portion.

The intermediate core portion includes: a high grammage portion located in a widthwise central region and having a higher grammage than the front core portion and the rear core portion; and low grammage parts located in both widthwise side regions and having a grammage lower than that of the high grammage part.

The high grammage part includes: a high-grammage and high-thickness portion located at a widthwise central portion; and a high-grammage low-thickness portion which is located on both sides in the width direction of the high-grammage high-thickness portion and is thinner than the high-grammage high-thickness portion.

Drawings

Fig. 1 is a plan view of a pad-type absorbent article according to an embodiment of the present invention.

Fig. 2 is a schematic plan view of an absorbent body constituting a part of the pad-type absorbent article of fig. 1 in a single body state.

Fig. 3 is a schematic plan view of the absorbent body of fig. 2 cut along line III-III passing through the linear portions provided in the peripheral groove portions of the absorbent core, and conceptually shows the relationship between the absorbent core and the core sheet.

Fig. 4 is a plan view showing an absorbent core constituting a part of the absorbent body of fig. 2.

Fig. 5 is an explanatory view for explaining a method of compressing both side portions in the width direction of a high grammage portion located at the center portion in the width direction of an intermediate core portion of an absorbent core to form a high grammage low thickness portion, and in this figure, a cross section of the intermediate core portion is schematically shown and a groove portion is not shown.

Fig. 6 is a view corresponding to fig. 3 of another embodiment of the present invention.

Fig. 7 is a plan view showing an absorbent core as a comparative example.

Detailed Description

Even during a physiological period, whether a weekday or a holiday, there are many cases where a woman has to perform the same activities as during a non-physiological period. When a pad-type absorbent article such as a sanitary napkin has a rectangular absorber, the absorbent article may rub against the groin or the excretory part to give a wearer a feeling of discomfort and prevent active movement, for example, when worn for a long time. Therefore, a technique for reducing friction between the absorbent article and the skin is desired.

The present invention relates to a pad-type absorbent article capable of reducing friction between the absorbent article and the skin of a wearer.

[ integral Structure of sanitary napkin ]

Hereinafter, in each drawing, the X-axis direction corresponds to the front-rear direction of the pad-type absorbent article (hereinafter, also referred to as an absorbent article) 1, the Y-axis direction corresponds to the width direction, and the Z-axis direction corresponds to the up-down direction (thickness direction). The X, Y and Z axes are orthogonal to each other. In the present specification, the Z-axis direction is defined as an upper side on a side close to the skin of the wearer when the absorbent article 1 is worn and a lower side on a side away from the skin.

The absorbent article 1 of the present embodiment is configured as a catamenial napkin, hereinafter referred to as a sanitary napkin 10.

As shown in fig. 1, the sanitary napkin 10 includes a main body M, a pair of wings W and a pair of rear wings F.

The main body M extends in the front-rear direction X and is fixed to an inner surface (a surface to be worn) of underwear of a wearer when worn. The main body M has an absorber 11 and has a function of absorbing liquid material (hereinafter, also referred to as "liquid") such as menstrual blood of a wearer.

The main body M has a front region M1, a middle region M2, and a rear region M3 defined along the front-rear direction X.

The front region M1 is a region disposed in front of the intermediate region M2 (on the abdominal side of the wearer), and is configured to face the front of the excretory part of the wearer when worn.

The intermediate region M2 is configured to face the excretory part of the wearer when worn. The intermediate region M2 may be located at the front of the body M as shown in the drawing, or may be located at the center of the body M.

The rear region M3 is a region disposed rearward of the intermediate region M2 (on the back side of the wearer), and is configured to face rearward of the excretory part of the wearer when worn.

The wing portion W is configured to greatly protrude outward in the width direction Y from the intermediate region M2.

The rear wing F is configured to bulge outward in the width direction Y from the rear region M3.

In addition, the sanitary napkin 10 may not have at least one of the wing portions W and the back wing portions F.

[ Structure of each part of sanitary napkin ]

As shown in fig. 1, the sanitary napkin 10 includes an absorbent body 11, a front sheet 12, a back sheet not shown, a pair of side sheets 14, and a compressed groove portion 16. In the main body M, the sanitary napkin 10 has a structure in which a back sheet, an absorbent body 11, and a front sheet 12 are laminated. The sanitary napkin 10 is configured such that the skin-facing surface 12a of the topsheet 12 comes into contact with the skin of the wearer when worn.

The absorber 11 has a front-rear direction in the X-axis direction and is disposed in the thickness direction center portion of the sanitary napkin 10. The absorbent body 11 absorbs liquid from the surface on the topsheet 12 side, and diffuses and retains the liquid therein. As for the absorbent body 11, it will be described later.

The topsheet 12 is a liquid-permeable sheet and is disposed on the absorbent body 11. The front sheet 12 constitutes an outer surface of the sanitary napkin 10 in the main body M above in the thickness direction.

The back sheet is arranged to face the front sheet 12 in the thickness direction with the absorber 11 interposed therebetween. The back sheet constitutes the outer surface of the sanitary napkin 10 below in the thickness direction. The back sheet is joined to the front sheet 12 and the side sheet 14 at the peripheral edge portion thereof by, for example, an adhesive, heat sealing, or the like.

The pair of side sheets 14 are arranged on the width direction peripheral edge of the sanitary napkin 10 so as to face each other in the width direction Y with the topsheet 12 interposed therebetween.

The compressed groove portions 16 are configured as linear grooves formed by compression processing of the absorbent body 11 and the topsheet 12.

(basic constitution of absorbent)

As shown in fig. 3, the absorbent body 11 has an absorbent core 20 and a core-spun sheet 30.

The absorbent core 20 has a function of absorbing and retaining liquid. The absorbent core 20 may be formed of a fiber aggregate containing hydrophilic fibers such as pulp fibers, or may have a structure in which a water-absorbent polymer is held by the fiber aggregate. Hereinafter, the components constituting the absorbent core 20 will be referred to as absorbent components.

As shown in fig. 2 and 3, the core-spun sheet 30 is wound in the width direction Y of the absorbent core 20 in such a manner as to cover the front and back surfaces of the absorbent core 20. The length of the core-wrapped sheet 30 in the X axis direction is formed to be the same as the length (total length) of the absorbent core 20 in the front-rear direction X, but is not limited thereto, and may be longer or shorter than the total length of the absorbent core 20.

The core sheet 30 covers the absorbent core 20 and has a function of, for example, maintaining the shape of the absorbent core 20. The core sheet is formed of, for example, thin and flexible paper such as tissue paper or liquid-permeable nonwoven fabric. The core-spun sheet 30 may be formed of 1 sheet or a plurality of sheets. The core-spun sheet 30 may be bonded to the front sheet 12 and the back sheet 13 with, for example, an adhesive applied in a predetermined pattern.

(Structure of absorbent core)

As shown in fig. 4, the absorbent core 20 has: a front core 21 located in the front region M1; a middle core 22 located in the middle region M2; and a rear core portion 23 located in the rear region M3. The front core portion 21 and the rear core portion 23 are positioned on both end portions sides in the front-rear direction X of the absorbent core 20, and the intermediate core portion 22 is positioned between the front core portion 21 and the rear core portion 23. The intermediate core 22 reaches the front side of the rear region M3 from the rear side of the front region M1 through the intermediate region M2. The absorbent core 20 has a planar shape that is bilaterally symmetric in the width direction Y.

Fig. 4 shows the widths D1, D2, and D3, which are the dimensions in the width direction Y of the front core portion 21, the intermediate core portion 22, and the rear core portion 23. 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 formed between the pair of indented regions 22s and having a width narrower than the front core portion 21 and the rear core portion 23 at the intermediate portion in the front-rear direction X.

In the present embodiment, the width D1 of the front core portion 21 is the same as the width D3 of the rear core portion 23. However, the width D1 of the front core portion 21 may be different from the width D3 of the rear core portion 23. Further, the widths of the front core portion 21, the intermediate core portion 22, and the rear core portion 23 may be respectively uneven. At this time, the maximum dimension in the width direction Y of each of the front core portion 21 and the rear core portion 23 can be set to the widths D1 and D3, respectively, and the minimum dimension in the width direction Y of the intermediate core portion 22 can be set to D2.

The intermediate core 22 is a portion facing the excretory part that is disposed facing the vaginal opening that is the excretory part of the wearer when the sanitary napkin 10 is worn. The front core portion 21 is disposed on the front side (ventral side) of the wearer with respect to the middle core portion 22, and the rear core portion 23 is disposed on the rear side (dorsal side) of the wearer with respect to the middle core portion 22.

As shown in fig. 4, the front core portion 21 has a tapered portion (inclined portion) 21a at the rear end, and the rear core portion 23 has a tapered portion 23a at the front end. The tapered portion 21a (23a) decreases the width of the front core portion 21 (rear core portion 23) toward the middle core portion 22. The indented portion region 22s corresponds to a space formed between both edges in the width direction Y of the intermediate core portion 22 and the

tapered portions

21a, 23 a.

A plurality of grooves are provided on the skin-facing surface 20a side 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 groove portion 29.

Further, a boundary groove portion 60 is provided at a boundary portion P1 between the front core portion 21 and the intermediate core portion 22, and a boundary groove portion 61 is provided at a boundary portion P2 between the intermediate core portion 22 and the rear core portion 23. The boundary portion P1 and the boundary portion P2 are respectively positioned so as to cross the absorbent core 20 in the width direction Y.

The boundary P1 is a portion between the front core portion 21 and the intermediate core portion 22 that is not included, and the boundary P2 is a portion between the rear core portion 23 and the intermediate core portion 22 that is not included.

The absorbent core 20 is divided into a plurality of pieces in a block shape by the low grammage longitudinal groove portions 27, the lateral groove portions 28, the peripheral groove portions 29, and the

boundary groove portions

60 and 61 of the absorbent member, which have a relatively low grammage. These grooves are configured to be recessed downward from the upper surface in the thickness direction (the surface on the skin side of the wearer) of the block-shaped divided block portion. On the other hand, the block portion is configured to protrude upward in the thickness direction.

In the absorbent core 20, the thickness of the region where the groove portions are formed, that is, the bottom portions where the groove portions are formed, is relatively thin compared to the region of the block portion where no groove portions are formed. The bottom portion forming the groove portion has a relatively low grammage as compared with the block portion, and has a lower rigidity as compared with the block portion. Therefore, when an external force is applied to the absorbent core 20, the absorbent core 20 is easily deformed with the groove portions as deformation starting points.

In the following description, the grammage of the front core portion 21, the intermediate core portion 22, and the rear core portion 23 refers to the grammage of the block portion excluding the

respective groove portions

27, 28, 29, 60, 61.

The vertical groove portions 27 extend in the front-rear direction X, and are arranged in 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.

The horizontal groove portions 28 extend in the width direction Y and are arranged at intervals in the front-rear direction X. 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. In the present embodiment, the

boundary grooves

60 and 61 formed in the boundary portions P1 and P2 are not included in the lateral groove 28. The

boundary groove portions

60 and 61 have a greater length in the front-rear direction X, i.e., a wider groove width, than the lateral groove portion 28.

The peripheral groove portion 29 is formed along the outer edge in the front-rear direction X of the high grammage portion 4 described below.

The configuration of the vertical groove portions 27, the horizontal groove portions 28, and the peripheral groove portions 29, such as the shape and arrangement thereof, is not limited to the configuration shown in fig. 4, and may be appropriately set based on the shape of the absorbent core 20, the required function, and the like.

By providing the vertical groove portions 27, the horizontal groove portions 28, the peripheral groove portions 29, and the

boundary groove portions

60 and 61, which are low in grammage and easily deformable, the flexibility of the absorbent core 20 can be improved, and the wearability can be improved. Further, by providing the groove portion, the discharged liquid can be quickly introduced into the space of the groove and taken into the absorbent core 20, and the liquid absorption rate can be increased. Further, by dividing the absorbent core 20 into a plurality of blocks, the surface area of the absorbent core 20 can be increased, and liquid can be efficiently absorbed and held.

(Structure of intermediate core)

As shown in fig. 3 and 4, the intermediate core portion 22 has a high grammage portion 4 having a high grammage of the absorbent member and a low grammage portion 25 having a lower grammage than the high grammage portion 4. The high grammage portion 4 is higher than the front core portion 21 and the rear core portion 23.

The high grammage portion 4 is located in the widthwise central region 65 of the intermediate core portion 22 and extends in the front-rear direction X. The low grammage portion 25 is located in the

widthwise side regions

66, 66 of the intermediate core portion 22 so as to extend in the front-rear direction X. The low grammage portion 25 extends in the front-rear direction X, and is disposed in a pair on the left and right so as to face each other in the width direction Y with the high grammage portion 4 interposed therebetween. The low grammage portion 25 is located below the upper surface of the high grammage and thickness portion 41. In the absorbent core 20, when an imaginary line parallel to the longitudinal direction X is drawn through the portion of the high grammage portion 4 having the largest length in the width direction, a portion on the inner side in the width direction Y than the imaginary line is the central region 65, and the outer side is the lateral region 66. In consideration of the fit to the groin of the wearer, the "portion having the largest widthwise length of the high grammage portion 4" is preferably present in the longitudinal central portion of the intermediate core portion 22.

The high grammage portion 4 has a high grammage high thickness portion 41 and a high grammage low thickness portion 42. The high grammage and high thickness portion 41 is located at the widthwise center portion. The pair of high-grammage and low-caliper portions 42 are disposed on both sides of the high-grammage and high-caliper portion 41 in the width direction Y so as to face each other with the high-grammage and high-caliper portion 41 interposed therebetween.

The high grammage high-thickness portion 41 and the high grammage low-thickness portion 42 are provided in a region of the absorbent core 20 where the indented portion region 22s along the front-rear direction X is provided, extending over the entire length in the front-rear direction of the intermediate core portion 22 having the narrowest width.

In the sanitary napkin 10, the high grammage and high thickness portion 41, the high grammage and low thickness portion 42, the peripheral edge groove portion 29, and the low grammage portion 25 are disposed in the center core portion 22 so as to be bilaterally symmetric about the vertical groove portion 27c located at the center in the width direction as the axis of symmetry.

The high grammage portion 4 is disposed so as to face the excretory part of the wearer when the sanitary napkin 10 is worn.

In fig. 4, the low grammage part 25 is shown as a dot pattern having a low density, and the high grammage part 4 is shown as a dot pattern having a density greater than that of the low grammage part 25. In the high grammage portion 4, the density of the dot pattern of the high grammage low-thickness portion 42 is shown to be higher than the density of the high grammage high-thickness portion 41.

The grammage of the high-grammage and low-thickness portion 42 is equal to the grammage of the high-grammage and high-thickness portion 41. However, the grammage of the high grammage and high thickness portion 41 and the high grammage and low thickness portion 42 need not be exactly the same, and from the viewpoint of absorption performance, the value obtained by dividing the difference between the higher grammage and the lower grammage by the higher grammage is preferably within 20%, and more preferably within 10%. The density of the absorbent member in the high grammage and low caliper portion 42 is higher than that of the absorbent member in the high grammage and low caliper portion 41, and is high. The high grammage and low thickness portion 42 is thinner than the high grammage and high thickness portion 41, and is equal to the low grammage portion 25. The high grammage and low thickness portion 42 is located between the high grammage and high thickness portion 41 and the low grammage portion 25.

In the intermediate core portion 22, the high grammage and low thickness portion 42 has the highest rigidity, the high grammage and high thickness portion 41 is the next highest, and the low grammage portion 25 is the lowest.

As shown in fig. 3, the high grammage and high thickness portion 41 of the high grammage portion 4 is formed thicker than the low grammage portion 25 and the high grammage and low thickness portion 42, and protrudes upward in the thickness direction (toward the topsheet 12). This ensures good fit between the central portion of the middle region M2 of the sanitary napkin 10 corresponding to the high grammage and high thickness portion 41 and the excretory part of the wearer.

In the present specification, a portion of the absorbent core 20 located on the outer side in the width direction Y than the high gram weight portion 4 is referred to as a side portion 44. Therefore, in the present embodiment, the portion of the absorbent core 20 including both the low grammage portion 25 and the linear portion 291 of the peripheral groove portion 29 is the side portion 44. As shown in fig. 4, the side portions 44 have an elongated shape extending in the front-rear direction X in plan view, and a pair thereof is provided so as to face each other in the width direction Y with the high grammage portion 4 interposed therebetween. The pair of side portions 44 are located on both sides of the high grammage portion 4 in the width direction Y so as to contact the high grammage portion 4, and are regions having a lower grammage than the high grammage portion 4.

The intermediate portion of the side portion 44 in the front-rear direction X has a uniform width along the front-rear direction X.

The high grammage portion 4 has a substantially semicircular shape whose width gradually decreases toward the front core portion 21 and the rear core portion 23 in the front portion and the rear portion, respectively, and the front portion and the rear portion of the side portion 4 are arranged along the high grammage portion 4 formed in such a substantially semicircular shape. Thus, the front and rear portions of the side portion 44 have a shape in which the width thereof gradually increases from the middle portion of the side portion 44 in the front-rear direction X toward the front and rear end portions.

Here, the 1 st virtual straight line along the width direction Y is drawn in the region of the absorbent core 20 where the straight portions 291 of the peripheral groove portions 29 are present. On the 1 st imaginary line, the region where the high grammage portion 4 is located is the central region 65 in the intermediate core portion 22, and the regions where the pair of side portions 44 located on both sides of the high grammage portion 4 are located are the side regions 66. The boundary between the central region 65 and the side regions 66 linearly extends along the front-rear direction X.

A 2 nd virtual straight line along the width direction Y is drawn in the region of the absorbent core 20 where the bent portions 292 of the peripheral groove portion 29 exist. On the 2 nd imaginary line, in the central region 65, there is a part of the side portion 44 in addition to the high grammage portion 4, and the boundary between the central region 65 and the side region 66 does not coincide with the boundary between the high grammage portion 4 and the side portion 44.

In the present embodiment, as shown in fig. 3, the width a of the high grammage high-thickness portion 41, the width b of the high grammage low-thickness portion 42, the width c of the low grammage portion 25, and the width e of the peripheral groove portion 29 respectively represent the width lengths (width lengths) in the width direction Y of the high grammage high-thickness portion 41, the high grammage low-thickness portion 42, the low grammage portion 25, and the peripheral groove portion 29 which are located on the 1 st imaginary straight line. The width f of the side portion 44 indicates the width length of the side portion 44 in the width direction Y on the 1 st virtual line, and corresponds to a value obtained by adding the width c of the low grammage portion 25 to the width e of the peripheral groove portion 29. The retracted portion covering portion 34 covering the retracted portion region 22s is located on the 1 st imaginary straight line, and the width d of the retracted portion covering portion 34 indicates the width length of the retracted portion covering portion 34 in the width direction Y. In the absence of the peripheral groove portion 29, the width c of the low grammage portion 25 is the same as the width f of the side portion 44.

As shown in fig. 3, in the absorbent core 11 of the sanitary napkin 10, the dimension b in the width direction Y of the high grammage low thickness portion 42 is smaller than the dimension f in the width direction Y of the side portion 44.

The method of providing the high-grammage low-thickness portion 42 having a high density in the high-grammage portion 4 is not particularly limited. For example, the high grammage and low thickness portion 42 can be formed by press working as shown in fig. 5.

As shown in fig. 5 (a), the intermediate core portion of the absorbent core 20' before press working has: a high grammage portion 4' which is arranged in the width direction center region 65 and has a high grammage; and low grammage portions 25 arranged in the widthwise side regions 66 and having a lower grammage than the high grammage portion 4'.

The absorbent core 20' is covered with a core sheet (not shown), and is introduced between both rolls of a pressing device including a press roll 50 having a concave portion 53 in a part of the peripheral surface and a smooth roll 51 having a smooth peripheral surface. As a result, as shown in fig. 5 (B), both sides in the width direction Y of the high grammage portion 4' are strongly pressed and compressed, and the high grammage and low thickness portion 42 is formed. During the pressing, the interval between the platen roller 50 and the smoothing roller 51 is set so that the low grammage portion 25 disposed in the both side regions 66 is not pressed. Further, the depth of the concave portion 53 is set in such a manner that the region corresponding to the concave portion 53 of the press roller 50 in the high grammage portion 4' is not pressurized.

In this way, the high grammage portion 4' is locally compressed, thereby forming the high grammage portion 4 having the high grammage and high thickness portion 41 and the high grammage and low thickness portion 42.

In the intermediate core portion 22, a

peripheral groove portion

29, 1

longitudinal groove portion

27c, and 4 lateral groove portions 28 are provided. Here, in order to distinguish from the vertical groove portions 27 provided in the other core portions, the vertical groove portion positioned in the intermediate core portion 22 will be referred to as a vertical groove portion 27c, and will be simply referred to as a vertical groove portion 27 when it is not particularly necessary to distinguish.

As shown in fig. 4, the peripheral groove portion 29 as the 1 st groove portion is formed between the high grammage portion 4 and the low grammage portion 25 so as to surround at least the periphery of the high grammage portion 4 in the front-rear direction X. The peripheral groove portion 29 is provided along the side edge of the high-grammage low-thickness portion 42. The low grammage portion 25 is provided along the side edge of the high grammage portion 4 with the peripheral groove portion 29 therebetween. The gram weight of the peripheral groove portion 29 is lower than that of the low gram weight portion 25.

The peripheral groove portion 29 is provided in the front-rear direction X, and includes a straight portion 291 extending in the front-rear direction X and a curved portion 292 communicating with the straight portion 291 and curved. The curved portion 292 forms the front end portion 45 and the rear end portion 46 of the high grammage portion 4 into a substantially semicircular shape. The shape is not limited to a semicircular shape, but is preferably a shape capable of dispersing an external force acting on the surface, such as a triangular shape, a trapezoidal shape, or a combined shape of a circular arc and a straight line.

The peripheral groove portion 29 communicates with a boundary groove portion 61(60) as a 2 nd groove portion extending in the width direction Y provided at a 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).

The rear end portion 46 of the high grammage portion 4 extending in the front-rear direction X is adjacent to the boundary groove portion 61, and the front end portion 45 of the high grammage portion 4 is adjacent to the boundary groove portion 60.

Further, the high grammage and low thickness portion 42 is not present at the front end portion and the rear end portion of the high grammage portion 4. In the region in the front-rear direction of the region corresponding to the high grammage low thickness portion 42 in which the high grammage portion 4 is not present in the intermediate core portion 22, the width of the low grammage portion 25 gradually increases from the intermediate portion in the front-rear direction X of the low grammage portion 25 toward both end portions.

The vertical groove portion 27c is located at the center in the width direction Y of the middle core portion 22, at the center in the width direction Y of the high grammage and high thickness portion 41, and is located on the same straight line as the vertical groove portion 27 located at the center in the width direction Y of each of the front core portion 21 and the rear core portion 23 and communicates with each other.

The 4 lateral groove portions 28 provided in the intermediate core portion 22 are arranged in parallel with each other at equal intervals so as to cross the intermediate core portion 22 in the width direction Y. The horizontal groove portion 28 is disposed so as to be orthogonal to the linear portion 291 of the peripheral groove portion 29.

(Structure of cored sheet)

As shown in fig. 2, the core-spun sheet 30 has: core covering sections (31-33) that cover the respective sections of the absorbent core (20); and a pair of tuck-in cover sections 34 that cover the pair of tuck-in regions 22s of the absorbent core 20.

The core covering section includes: a front core covering section 31 that covers the front core section 21; a center core covering portion 32 that covers the center core portion 22; and a rear core covering portion 33 that covers the rear core portion 23. In FIG. 2, the boundaries between the core covering parts 31 to 33 and the retracted part covering part 34 are shown by chain lines.

The core-spun sheet 30 is composed of a sheet having sufficiently low rigidity compared to the absorbent core 20, and therefore covers the absorbent core 20 in a shape corresponding to the shape of the absorbent core 20. For example, the intermediate core covering portion 32 is deformed into a shape corresponding to the shape of the protruding portion (high grammage portion 4) of the front face 20a of the intermediate core portion 22 as shown in fig. 3.

On the other hand, the indented portion covering portion 34 extends from the outer edge portion of the intermediate core portion 22 to the indented portion region 22s by spanning between the front core portion 21 and the rear core portion 23. Therefore, the retracted portion covering portion 34 is maintained in a shape corresponding to the retracted portion region 22s in a state where a constant tension is applied in the front-rear direction X.

In the inside of the retracted part covering section 34, as shown in fig. 3, there is no absorbent member constituting the absorbent core 20, but fibers protruding outward from the peripheral edge of the absorbent core 20 or a part of the absorbent member separated from the absorbent core 20 may be present locally. In addition, the retracted portion covering section 34 is depicted in fig. 3 as having a thickness in the thickness direction Z equivalent to the low grammage portion 25 of the absorbent core, but in the absorbent article, there is substantially no space in the thickness direction, and it is preferable that the front surface region 341 is in contact with the back surface region 342.

[ action and Effect of the present embodiment ]

By using the absorbent core 20 having a relatively narrow width of the intermediate core portion 22 and having a contracted inward shape as a whole, in the sanitary napkin 10, the region of the main body M including the contracted inward region 22s has a lower rigidity and is flexible than the region including the absorbent core 20. Therefore, when worn, the intermediate region M2 of the sanitary napkin 10 is a region that receives an external force from both legs of the wearer that are positioned on the outer side in the width direction Y toward the inner side in the width direction Y, but this region has low rigidity and is soft, so friction between the groin portion and the sanitary napkin 10 can be reduced. This can provide a comfortable feeling of use to the wearer.

Further, the intermediate core portion 22 of the absorbent core 20 is provided with a high grammage portion 4 at the center in the width direction Y and low grammage portions 25 on both sides thereof.

The high grammage part 4 has a high grammage high thickness part 41 at the center in the width direction Y, and a pair of high grammage low thickness parts 42 having a smaller thickness than the high grammage high thickness part 41 are provided between the high grammage thickness part 41 and the low grammage part 25. The high grammage and low thickness portion 42 makes it difficult for the force from the thigh portion applied to the low grammage portion 25 to be transmitted to the high grammage and high thickness portion 41. Therefore, the high grammage portion and high thickness portion 41 is less likely to be deformed unnecessarily, and the high grammage portion and high thickness portion 41 is likely to be closely attached to the excretory part of the wearer, so that the fit property is improved. Further, although the region facing the excretory part and the intermediate core part 22 around it are deformed to locally generate high rigidity, and thus may cause a strong frictional feeling with the skin of the wearer, the presence of the indented part region 22s can suppress deformation of the low grammage part 25 and the high grammage and low thickness part 42, and thus can reduce the frictional feeling.

Furthermore, the structure of the present invention can also bring about a good influence on the absorption performance. Since the high grammage and low thickness portion 42 is present, the high grammage and high thickness portion 41 is less likely to be deformed unnecessarily, and therefore the high grammage and high thickness portion 41 is likely to be in close contact with the excretory part of the wearer. Since the bodily fluid discharged from the excretory part is easily taken into the absorbent core 20, the high grammage part 4 easily holds a large amount of bodily fluid, and lateral leakage of bodily fluid can be suppressed in the retracted part.

Further, the absorbent member of the high grammage and low thickness portion 42 is formed more densely than the high grammage and high thickness portion 41, and the force of sucking the liquid is more excellent. The absorbent core 20 has a function of sucking liquid from the skin surface side, and the force of sucking the liquid is generated by the capillary force of the absorbent core 20, which becomes stronger in proportion to the density of the absorbent member constituting the absorbent core. That is, by providing the high-density high-grammage low-thickness portion 42, capillary force acts to easily suck liquid from the skin surface side and to suppress the sucked liquid from reaching the side edge of the absorbent core. Further, since the deformation of the high grammage and low thickness portion 42 can be suppressed by the function of the indented portion region 22s, the body fluid held by the high grammage and low thickness portion 42 can be suppressed from being pushed out to the low grammage portion 25 side during wearing.

Furthermore, since the high-grammage low-thickness portion 42 having a high density after compression is provided extending in the front-rear direction X over the entire length of the narrow intermediate core portion 22, the liquid absorbed in the high-grammage low-thickness portion 42 is guided in the direction of diffusion of the liquid in the front-rear direction X, and side leakage is further suppressed. In this way, even in a form in which the width of the intermediate core portion 22, which is the excretion portion-facing portion, is narrow, the side leakage can be suppressed by providing the high-grammage low-thickness portion 42 having a high density.

When the absorbent body 11 receives an external force from the legs of the wearer positioned on the outer side in the width direction Y toward the inner side in the width direction Y during wearing, typically, as shown in fig. 3, the contracted portion covering section 34 corresponding to the contracted portion region 22s, where the absorbent core 20 is not present, and which has low rigidity is deformed first, and then the low grammage portion 25 is deformed.

By providing the retracted region 22s in the absorbent core in this manner, the external force applied to the intermediate core portion 22 during wearing can be reduced as compared with the case where an absorbent core is used that does not have a retracted region formed with an equal width in the front-rear direction X. This can suppress deformation of the intermediate core portion 22, and can suppress liquid leakage due to the deformation. Further, by suppressing the deformation of the intermediate core portion 22, the occurrence of the deformation of the rear core portion due to the transmission of the deformation of the intermediate core portion to the rear core portion can be suppressed, and therefore, the liquid leakage due to the deformation of the rear core portion can be suppressed.

In the sanitary napkin 10, the high-grammage and high-thickness portion 41 is formed so as to protrude in the skin direction over the entire length of the intermediate core portion 22. This ensures a good fit between the high-grammage and high-thickness portion 41 and the excretory part when the sanitary napkin 1 is worn.

As described above, the absorbent article of the present embodiment can reduce friction between the groin portions and the sanitary napkin, and provide a comfortable feeling of use to the wearer with a reduced feeling of firmness, and further, has high conformability to the excretory part and excellent liquid absorption performance that is less likely to cause side leakage.

Further, as shown in fig. 3, in the sanitary napkin 10, the width b in the width direction Y of the high grammage low thickness portion 42 is preferably smaller than the width f of the side portion. Further, the dimension b in the width direction Y of the high grammage low thickness portion 42 is preferably smaller than the width c of the low grammage portion 25. These relationships may be satisfied by the length of 1/2, which is the total length of the intermediate core 22 in the front-rear direction X, but preferably the relationship is satisfied in the portion in the front-rear direction X where the side region 66 is located, and more preferably the relationship is satisfied over the total length of the intermediate core 22 in the front-rear direction X.

This makes it possible to relatively reduce the ratio of the high grammage and low thickness portion 42 having the highest rigidity in the intermediate core portion 22 in the width direction Y of the intermediate core portion 22, and to reduce friction between the skin of the wearer and the sanitary napkin 1. Further, by making the width b smaller than at least one of the width c and the width f, the length from the side edge portion in the width direction Y of the intermediate core portion 22 to the high grammage low-thickness portion 42 having high rigidity can be made longer. That is, since the width of the side portion 44 having low rigidity, preferably the side region 66, can be increased, friction between the groin portion and the sanitary napkin 1 can be reduced when worn.

Further, by providing the peripheral groove portion 29 having a low grammage between the high grammage and low thickness portion 42 and the low grammage portion 25 along the side edge of the high grammage and low thickness portion 42, flexibility of the intermediate core portion 22 can be increased. Thus, when the sanitary napkin 1 comes into contact with the skin of the wearer during wearing, the absorbent core 20 changes softly, and the friction at the groin area is alleviated.

Further, by providing the peripheral groove portion 29 which is lower in grammage than the low grammage portion 25 and is easily deformed, the deformation around the high grammage portion 4 is absorbed by the peripheral groove portion 29, and therefore the deformation of the low grammage portion 25 is not easily transmitted to the high grammage portion 4. That is, when worn, external forces received from the left and right leg sides are relieved by the peripheral groove portions 29, and the external force transmitted to the high gram weight portion 4 is further reduced. Therefore, deformation of the high grammage portion 4 can be suppressed, and liquid leakage can be suppressed.

Further, by providing the

boundary groove portions

60 and 61, the

boundary groove portions

60 and 61 become folding points when worn, and the sanitary napkin 1 becomes easily bendable in the front-rear direction X, and is easily deformed along the wearer's body. The bent portions 292 of the peripheral groove portion 29 disposed over the front-rear direction X also serve as bending points during wearing, so that the sanitary napkin 1 is easily bent and deformed along the wearer's body. This improves the fit, reduces friction, reduces the gap between the skin and the sanitary napkin 1, and suppresses liquid leakage.

Further, since the peripheral groove portion 29 communicates with the boundary groove portions 61(60), the external force acting on the intermediate core portion 22 is further relaxed in the boundary groove portions 61(60) after passing through the peripheral groove portion 29, and therefore, the deformation of the intermediate core portion 22 is not easily transmitted to the rear core portion 23 (the front core portion 21).

Further, the deformation occurring in each of the front core portions 21 and the rear core portions 23 is relaxed at the

boundary groove portions

60 and 61 and is less likely to be transmitted to the intermediate core portion 22, so that the deformation of the high grammage portion 4 can be effectively suppressed.

Further, by providing the lateral groove portions 28 and the peripheral groove portions 29 in the intermediate core portion 22 and dividing the low grammage portion 25 into a plurality of blocks, a certain effect of surrounding the deformed region in units of blocks can be obtained. This can suppress the transmission of external force to the high grammage portion 4, and further improve the effect of preventing deformation of the high grammage portion 4.

Further, as shown in fig. 4, in the low grammage portion 25 of the intermediate core portion 22, there is no longitudinal groove portion 27 having a lower grammage than the block portion. In other words, the low grammage portion 25 of the intermediate core portion 22 does not have the vertical groove portion 27 that divides the low grammage portion 25 in the width direction Y. Further, the longitudinal groove portion 27 of the front core portion and the longitudinal groove portion 27 of the rear core portion are present in front of and behind the low grammage portion 25, respectively. With this configuration, while the absorption capacity of the low grammage portion 25 of the intermediate core portion 22 is maintained, the load from the groin portion can be released to the front and rear core portions by the longitudinal grooves 27 of the front and rear core portions, and the unexpected deformation of the high grammage portion 4 can be further suppressed.

Further, when the high grammage portion 4 is shaped such that the width thereof gradually narrows in the front and rear directions as shown in fig. 4, the force applied from the thigh portion to the low grammage portion 25 is easily released to the front and rear portions of the intermediate core portion 22. Therefore, even if an abnormally strong force is applied to the intermediate core portion 22, the deformation of the intermediate core portion 22 is easily suppressed. Further, in the high grammage portion 4, when the high grammage low-thickness portion 42 is not present at the front end portion and the rear end portion thereof and only the high grammage high-thickness portion 41 is present, the width of the low grammage portion 25 gradually increases from the middle portion in the front-rear direction X of the low grammage portion 25 toward both end portions, and therefore, this effect is more easily obtained.

[ additional description of the present embodiment ]

Hereinafter, the present embodiment will be described in a supplementary manner.

Numerical examples of the respective configurations are explained, but these numerical values are examples and are not limited to the numerical values described herein.

(numerical example of each Structure)

The widths D1, D3 of the front core portion 21 and the rear core portion 23 are preferably 60mm or more, more preferably 70mm or more, and preferably 100mm or less, more preferably 90mm or less in the case of a sanitary napkin for menstrual period.

The thickness of the front core portion 21 and the rear core portion 23 is preferably 1.5mm or more, more preferably 2mm or more, and preferably 6mm or less, more preferably 5.5mm or less. The grammage of the front core portion 21 and the rear core portion 23 is preferably 90g/m²Above, more preferably 100g/m²Above, and preferably 350g/m²Hereinafter, more preferably 300g/m²The following.

The width D2 of the intermediate core 22 is typically formed to be larger than the crotch width of a typical wearer (about 30mm), preferably 35mm or more, more preferably 40mm or more, and preferably 75mm or less, more preferably 70mm or less. This makes it possible to cope with a displacement in the wearing position in the width direction Y, and to give a feeling of comfort to the wearer.

The length of the intermediate core 22 in the front-rear direction X is, for example, preferably 60mm or more, more preferably 80mm or more, and preferably 180mm or less, more preferably 170mm or less. This enables the intermediate core portion 22 to face the excretory part of the wearer even when the wearing position in the front-rear direction X is shifted.

Hereinafter, when the width of the high grammage portion 4 is not uniform in the front-rear direction X, the width of the high grammage portion 4, the width of the high grammage portion high thickness portion 41, the width of the high grammage portion low thickness portion 42, and the width of the low grammage portion 25 are widths at a portion where an imaginary line is drawn in the width direction Y at a portion where the width of the high grammage portion 4 is the largest.

The width of the high grammage portion 4 disposed in the widthwise central region of the intermediate core portion 22 is preferably 15mm or more, more preferably 20mm or more, and preferably 60mm or less, more preferably 50mm or less. By setting this width to this range, a sufficient absorption amount can be ensured.

The high grammage portion 4 has a high grammage low thickness portion 42 obtained by locally reducing the thickness by compressing both side portions thereof. By reducing the thickness in this way, the feeling of firmness at the time of wearing can be reduced.

As shown in fig. 3, the width a of the high grammage and high thickness portion 41 is preferably 10mm or more, more preferably 15mm or more, and preferably 40mm or less, more preferably 30mm or less. By setting the width of the high grammage and high thickness portion 41 which becomes the protruding portion of the absorbent core 22 to this range, the fit to the excretory part of the wearer can be improved.

The width b of the high grammage and low thickness portion 42 is preferably 2mm or more, more preferably 3mm or more, and preferably 10mm or less, more preferably 7.5mm or less, from the viewpoint of diffusing the absorbed liquid in the front-rear direction X while suppressing the occurrence of friction.

Further, it is preferable that the width f of the side portion 44 is wider than the width b of the high-gram-weight low-thickness portion 42 because friction of the sanitary napkin 10 in the groin portion can be further suppressed. The width f of the side portion 44 is preferably 10mm or more, and more preferably 12mm or more. And is preferably 30mm or less, more preferably 25mm or less. The width c of the low grammage portion 25 is preferably 5mm or more, and more preferably 7.5mm or more. The width c of the low grammage portion 25 is preferably 30mm or less, and more preferably 20mm 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, more preferably 4 times or less the width b of the high grammage low thickness portion 42.

Further, the dimension b in the width direction Y of the high grammage low thickness portion 42 is preferably smaller than the dimension d in the width direction Y of the retracted portion covering portion 34. The width d of the retracted portion covering portion 34 is preferably 5mm or more, more preferably 10mm or more, and preferably 30mm or less, more preferably 20mm or less.

From the viewpoint of sufficiently securing the liquid absorption capacity, the grammage of the high grammage portion 4 is preferably 250g/m²Above, more preferably 300g/m²Above, and preferably 700g/m²Hereinafter, more preferably 650g/m²The following.

From the viewpoint of making the liquid absorbability appropriate and reducing the rigidity, the grammage of the low grammage portion 25 is preferably 90g/m²Above, more preferably 100g/m²Above, and preferably 350g/m²Hereinafter, more preferably 300g/m²The following.

The thickness of the high grammage and high thickness portion 41 is preferably 2mm or more, more preferably 2.5mm or more, and preferably 9mm or less, more preferably 8mm or less.

From the viewpoint of reducing the hard feeling, the thickness of the high grammage and low thickness portion 42 and the low grammage portion 25 is preferably 1.5mm or more, more preferably 2mm or more, and preferably 6mm or less, more preferably 5.5mm or less.

From the viewpoint of the fit of the high grammage and high thickness portion 41 to the excretory part, the difference between the thickness of the high grammage and high thickness portion 41 and the thickness of the high grammage and low thickness portion 42 is preferably 0.5mm or more, more preferably 1mm or more, and preferably 5mm or less, more preferably 4mm or less.

The density of the high grammage and high thickness portion 41 is preferably 0.073g/cm³Above, more preferably 0.091g/cm³Above, and preferably 0.182g/cm³Hereinafter, more preferably 0.164g/cm³The following.

The density of the high grammage and low thickness portion 42 is preferably 0.114g/cm³Above, more preferably 0.143g/cm³Above, and preferably 0.286g/cm³Hereinafter, more preferably 0.257g/cm³The following.

The density of the high grammage and 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, more preferably 2.2 times or less, of the high grammage and high thickness portion 41.

The width of the peripheral groove portion 29, the vertical groove portion 27, and the horizontal groove portion 28 is preferably 0.5mm or more, more preferably 1mm or more, and preferably 10mm or less, more preferably 5mm or less.

The width of the boundary groove portions 61(60) arranged at the boundary between the intermediate core portion 22 and the rear core portion 23 (front core portion 21), in other words, arranged to extend in the width direction Y between the high grammage portion 4 and the rear core portion 23 (front core portion 21), is preferably 1.5mm or more, more preferably 2mm or more, and is preferably 3.5mm or less, more preferably 3mm or less.

The gram weight of the peripheral groove portion 29, the vertical groove portion 27 and the horizontal groove portion 28 is lower than that of the block portion, and is preferably 50g/m²Above, and preferably 250g/m²The following.

The numerical values in the above-described configurations can be measured by the following measurement methods.

(method of measuring the width of each portion of the absorbent core)

The width of the absorbent core, the high grammage and high thickness portion, the high grammage and low thickness portion, the low grammage portion, and the lateral outer portions can be measured by horizontally placing the absorbent core, and magnifying the skin-facing surface 20a with the measurement magnification adjusted by a microscope (VHX-1000 manufactured by KEYENCE corporation).

(method of measuring grammage of each part of absorbent core)

Each portion of the absorbent core 20 to be measured was cut with a single-blade razor manufactured by Feather corporation to obtain a small piece having a predetermined area. The weight of these chips was measured using an electronic balance (electronic balance GR-300 manufactured by A & D, accuracy: 4 digits after decimal point). The determined weight was divided by the area of the small pieces of each part to calculate the grammage of the small pieces. The average of the grammage of 5 chips was defined as grammage for each portion.

(method of measuring Density in high-grammage high-thickness portion and high-grammage low-thickness portion)

The density was calculated by dividing the grammage determined in the same manner as the grammage measurement method described above by the thickness of the piece to be measured.

The thickness of the piece to be measured is measured by measuring the thickness of the piece cut out to measure the grammage. A circular aluminum plate having a diameter of 25mm, a thickness of 3mm and a mass of 2.45G was horizontally set on the measurement surface of the piece cut out from the absorbent core, and the thickness of the sample was measured using a noncontact laser scale meter (laser head LK-G30, displacement meter LK-GD500) manufactured by KEYENCE. When the cut piece has a small size and is difficult to measure with a noncontact laser displacement meter, the cut sample may be measured by observing a cross section thereof at a magnification of 20 to 100 times with a microscope (VHX-1000 manufactured by KEYENCE).

While the embodiments of the present invention have been described above, it is needless to say that the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention.

For example, in the above embodiment, the high grammage portion 4 protrudes upward in the thickness direction Z, but instead of this configuration, a form may be adopted in which it protrudes downward in the thickness direction Z as in the absorbent body 24 shown in fig. 6. In the above-described embodiment, the various groove portions such as the vertical groove portion 27, the horizontal groove portion 28, the peripheral groove portion 29, and the

boundary groove portions

60 and 61 provided in the absorbent core 20 have openings on the upper side in the thickness direction Z, but instead of this structure, a structure having openings on the lower side in the thickness direction Z, such as the absorbent body 24 shown in fig. 6, may be employed.

In the above-described embodiments, the example of the catamenial napkin is shown as the absorbent article, but the present invention is not limited to this. The absorbent article of the invention may also be, for example, an incontinence pad or a vaginal discharge pad or the like.

The present invention will be further described with reference to the following examples, but the present invention is not limited to these examples.

(1)

A pad-type absorbent article having an absorbent core, the absorbent core having: a front core portion and a rear core portion located at both end portions in the front-rear direction; and an intermediate core portion located between the front core portion and the rear core portion, wherein a length of the intermediate core portion in a width direction orthogonal to a front-rear direction is shorter than the front core portion and the rear core portion, the intermediate core portion having: a high grammage portion located in a widthwise central region and having a higher grammage than the front core portion and the rear core portion; and low grammage parts located in both widthwise side regions and having a lower grammage than the high grammage part, the high grammage part having: a high grammage and high thickness portion located at a widthwise central portion; and high-grammage low-thickness portions which are located on both sides in the width direction of the high-grammage high-thickness portion and which are thinner than the high-grammage high-thickness portion.

(2)

The pad-type absorbent article according to (1) above, wherein a dimension in the width direction of the low grammage portion is larger than a dimension in the width direction of the high grammage low thickness portion.

(3)

The pad-type absorbent article according to (1) or (2), wherein the high grammage and low thickness portion is disposed over the entire length of the intermediate core portion in the front-rear direction.

(4)

The pad-type absorbent article according to any one of the above (1) to (3), wherein the intermediate core portion has a 1 st groove portion having a lower grammage than the low grammage portion in a front-rear direction between the high grammage and low thickness portion and the low grammage portion.

(5)

The pad-type absorbent article according to any one of the above (1) to (4), wherein the absorbent core has a 2 nd groove portion having a lower grammage than the low-grammage portion at a boundary between the intermediate core portion and the rear core portion.

(6)

The pad-type absorbent article according to any one of the above (1) to (5), wherein the absorbent core has a 2 nd groove portion having a lower grammage than the low-grammage portion at a boundary between the front core portion and the intermediate core portion.

(7)

The pad-type absorbent article according to (5) or (6), wherein the intermediate core portion has a 1 st groove portion having a lower grammage than the low grammage portion in a front-rear direction between the high-grammage low-thickness portion and the low-grammage portion,

the 2 nd groove part communicates with the 1 st groove part.

(8)

The pad-type absorbent article according to any one of the above (1) to (7), wherein the front core portion has a tapered portion at a rear end, and the rear core portion has a tapered portion at a front end.

(9)

The pad-type absorbent article according to any one of the above (1) to (8), wherein the front core portion, the intermediate core portion, and the rear core portion have a longitudinal groove portion extending in a front-rear direction and a lateral groove portion extending in a width direction.

(10)

The pad-type absorbent article according to any one of the above (1) to (9), wherein a value obtained by dividing a difference between a higher grammage and a lower grammage of the high-grammage and low-thickness portion and the high-grammage and high-thickness portion by a higher grammage is preferably within 20%, and more preferably within 10%.

(11)

The pad-type absorbent article according to any one of the above (1) to (10), wherein 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 respective widths of the tapered portions decrease toward the middle core portion.

(12)

The pad-type absorbent article according to any one of the above (1) to (11), wherein the intermediate core portion is formed between a pair of indented regions located at a front-rear direction intermediate portion of the absorbent core,

the absorbent core is covered with a core sheet, and the core sheet is stretched between the front core section and the rear core section at a position further to the outside in the width direction than the side edge section of the center core section, thereby having a retracted section covering section extending from the outer edge section of the center core section to the retracted section region.

(13)

The pad-type absorbent article according to item (11) above, wherein no absorbent member constituting the absorbent core is present inside the retracted portion covering section.

(14)

The pad-type absorbent article according to (11) or (12) above, wherein a dimension in the width direction of the high grammage low-thickness portion is smaller than a dimension in the width direction of the retracted portion covering portion.

(15)

The pad-type absorbent article according to any one of the above (1) to (14), wherein the intermediate core portion is divided into a plurality of pieces by the lateral groove portions,

the low grammage portion of the intermediate core portion does not have a longitudinal groove portion that divides the low grammage portion in the width direction and has a lower grammage than a block portion of the low grammage portion,

the front core portion and the rear core portion have longitudinal groove portions in front of and behind the low grammage portion, respectively.

(16)

The pad-type absorbent article according to any one of the above (1) to (15), wherein the high grammage portion has a shape in which a width gradually decreases in a front portion and a rear portion.

(17)

The pad-type absorbent article according to any one of the above (1) to (16), wherein the high grammage low-thickness portion is not present at the front end portion and the rear end portion of the high grammage portion, and the width of the low grammage portion gradually increases from the middle portion in the front-rear direction of the low grammage portion toward both end portions in the front-rear direction of the intermediate core portion.

(18)

The pad-type absorbent article according to any one of the above (1) to (17), wherein the high grammage and high thickness portion has a density of 0.073g/cm³Above, more preferably 0.091g/cm³Above, and preferably 0.182g/cm³Hereinafter, more preferably 0.164g/cm³。

(19)

Any of the above (1) to (18)The pad-type absorbent article according to any one of the above aspects, wherein the density of the high grammage and low thickness portion 42 is preferably 0.114g/cm³Above, more preferably 0.143g/cm³Above, and preferably 0.286g/cm³Hereinafter, more preferably 0.257g/cm³。

(20)

The pad-type absorbent article according to any one of the above (1) to (19), wherein the pad-type absorbent article is a catamenial sanitary napkin.

(21)

The pad-type absorbent article according to any one of the above (1) to (20), wherein the width of the front core portion and the width of the rear core portion are preferably 60mm or more, more preferably 70mm or more, and preferably 100mm or less, more preferably 90mm or less.

(22)

The pad-type absorbent article according to any one of the above (1) to (21), wherein the front core portion and the rear core portion have a thickness of preferably 2mm or more, more preferably 2.5mm or more, and preferably 7mm or less, more preferably 6mm or less.

(23)

The pad-type absorbent article according to any one of the above (1) to (22), wherein the grammage of the front core portion and the rear core portion is preferably 90g/m²Above, more preferably 100g/m²Above, and preferably 300g/m²Hereinafter, it is more preferably 250g/m²The following.

(24)

The pad-type absorbent article according to any one of the above (1) to (23), wherein the width of the intermediate core portion is preferably 35mm or more, more preferably 40mm or more, and preferably 75mm or less, more preferably 70mm or less.

(25)

The pad-type absorbent article according to any one of the above (1) to (24), wherein the length of the intermediate core portion in the front-rear direction is preferably 60mm or more, more preferably 80mm or more, and preferably 180mm or less, more preferably 170mm or less.

(26)

The pad-type absorbent article according to any one of the above (1) to (25), wherein the width of the high grammage and low thickness portion is preferably 2mm or more, more preferably 3mm or more, and preferably 10mm or less, more preferably 7.5mm or less.

(27)

The pad-type absorbent article according to any one of the above (1) to (26), wherein the intermediate core portion has a pair of side portions including the low grammage portion positioned on both sides in the width direction of the high grammage 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, more preferably 4 times or less the width of the high grammage low-thickness portion.

[ example 1]

Catamenial sanitary napkins having the same basic structure as the sanitary napkin 10 shown in fig. 1-4 are made. Using a grammage of 74g/m²The hot-air nonwoven fabric used as the front sheet 12 has a grammage of 25g/m²The moisture-impermeable polyethylene film of (2) as a back sheet, using a grammage of 20g/m²The water repellent spunbonded nonwoven fabric of (1) is used as a side sheet.

The absorbent core used the following manner of the contracted shape shown in fig. 4: the width of the middle core portion 22 is 65mm and the dimension in the front-rear direction X is 90mm, the width of the front core portion 21 is 72mm and the dimension in the front-rear direction X is 23mm, and the width of the rear core portion 23 is 72mm and the dimension in the front-rear direction X is 82 mm.

The absorbent core is provided with a plurality of lateral grooves, vertical grooves, peripheral grooves, and boundary grooves, as in the embodiment shown in fig. 4. The gram weight of these grooves was 75g/m²The thickness of the bottom portion forming the groove portion was 2 mm.

The high grammage and high thickness portion 41 has a width a of 20mm and the high grammage and low thickness portion 42 has a width b of 5 mm. The width c of the low grammage portion 25 is 16 mm. The peripheral groove portion 29 and the vertical groove portion 27c provided in the intermediate core portion 22 have a groove width of 1.5 mm.

In the front core portion 21 and the rear core portion 23, 5 longitudinal groove portions 27 are provided, of which 3 longitudinal groove portions 27 located in the central portion have a width of 4mm, and 2 longitudinal groove portions 1 in total having a width of 1.5mm are present on both sides of the 3 longitudinal groove portions 27. The width-directional dimensions of the respective blocks provided in the front core portion 21 and the rear core portion 23 are equal.

In the absorbent core 20, the groove width (dimension in the front-rear direction X) of the lateral groove portions 28 was 2 mm. The groove widths of the

boundary groove portions

60 and 61 are 2.5 mm.

The grammage of the front core part 21 and the rear core part 23 is 200g/m²The thickness is 3.5 mm. In the intermediate core portion 22, the grammage of the low grammage portion 25 is 200g/m²The thickness is 3.5mm, and the grammage of the high grammage part 4 is 440g/m². The high grammage portion 4 is partially compressed, thereby providing a high grammage and high thickness portion 41 and a high grammage and low thickness portion 42. The high grammage and high thickness portion 41 is 5.5mm thick and the high grammage and low thickness portion 42 is 3.5mm thick. The density of the high grammage and high thickness portion 41 was 0.080g/m³The density of the high-grammage and low-thickness portion 42 is 0.126g/m³。

The sanitary napkin of example 1 was produced by covering the absorbent core of the above-described form with a core-covering sheet to form an absorbent body, sandwiching the absorbent body between a front sheet and a back sheet, and further providing a side sheet. The absorbent body and the front sheet, the absorbent body and the back sheet, the side sheets and the front sheet, and the front sheet and the back sheet are bonded to each other with an adhesive interposed therebetween.

[ example 2]

A sanitary napkin having an indented portion was produced in the same manner as in example 1 except that the grammage of the high grammage portion 4 of the intermediate core 22, the thickness and density of the high grammage high-thickness portion 41, the thickness and density of the high grammage low-thickness portion 42, and the widths of the front and rear core portions were different from those in example 1.

In the sanitary napkin of example 2, the grammage of the high grammage portion 4 was 550g/m². The high-grammage and high-thickness part 41 has a thickness of 7.0mm and a density of 0.079g/m³The high grammage and low thickness portion 42 has a thickness of 3.5mm and a density of 0.157g/m³。

The absorbent core used the following manner of the contracted shape shown in fig. 4: the width of the middle core portion 22 is 65mm and the dimension in the front-rear direction X is 130mm, the width of the front core portion 21 is 80mm and the dimension in the front-rear direction X is 36mm, and the width of the rear core portion 23 is 80mm and the dimension in the front-rear direction X is 137 mm.

[ comparative example ]

Fig. 7 corresponds to the absorbent core described in patent document 2. The absorbent core of fig. 7 has a different basic structure and number of block portions from those of the absorbent core described in patent document 2, but is common in that it has no inward-contracting portion, has a uniform width in the front-rear direction X, and has a high grammage portion, which is partially compressed, in the intermediate core portion.

A sanitary napkin of a comparative example was produced in the same manner as the sanitary napkin of example 1 except that the shape of the high grammage portion 4 of the absorbent core 70 in the form shown in fig. 7 was formed into an elliptical shape in which the shapes of the front end portion and the rear end portion of the high grammage portion 4 in the above-described example were substantially semicircular. The absorbent core 70 in the form shown in fig. 7 is equal in width in the front-rear direction X and 72mm in width, unlike the absorbent cores having the retracted portions of examples 1 and 2. In fig. 7, the same components as those of the absorbent core are denoted by the same reference numerals.

The absorbent core 70 is provided with a plurality of horizontal grooves 28, vertical grooves 27, peripheral grooves 29, and

boundary grooves

60, 61. The grammage and thickness of these grooves were the same as in examples 1 and 2. In the absorbent core 70, the groove widths of the longitudinal groove portions 27 and the peripheral groove portions 29 are each 1.5 mm. The

boundary grooves

60, 61 have a groove width of 2mm, which is the same as that of the horizontal groove 28.

The 3 longitudinal groove portions 27 formed in the intermediate core portion 22 are positioned on the same straight line as the 5 longitudinal groove portions 27 positioned in the front core portion 21 and the rear core portion 23, respectively.

The block portions 71 provided in the center core portion 21 and the rear core portion 23 have the same dimension in the width direction.

The grammage and thickness of the high grammage portion 4 and the low grammage portion 25, and the thickness, density, and width of the high grammage high thickness portion 41 and the high grammage low thickness portion 42 are the same as those of example 1.

[ evaluation ]

The sanitary napkins of examples 1 and 2 and the sanitary napkins of comparative examples were evaluated for absorbency and friction according to the following evaluation criteria by the following methods, and the evaluation results are shown in table 1.

(method of evaluating absorbency)

A menstrual sanitary napkin to be evaluated is fixed to menstrual shorts and worn on a dynamic model imitating the lower body of a human body. As a dynamic model of a human body, a movable female lumbar model capable of walking movement of both legs is used. The walking motion of the dynamic model was started, and 1 minute after the start of the walking motion, 2g of the dummy blood (1 st time) was injected from the liquid discharge point. Further, 3g of the mock blood was injected 3 minutes after the end of the 1 st liquid injection (2 nd time). Further, 2g of the mock blood was injected 3 minutes after the end of the 2 nd liquid injection (3 rd time). After 3 rd, the operation of injecting 2g of the simulant blood after 3 minutes from the time of the liquid injection was repeated, the liquid injection operation was terminated at the time point when the simulant blood oozed out from the flap portion of the sanitary napkin, and the total weight of the injected simulant blood before the time point was set as the dynamic maximum absorption amount.

As the simulated blood, a simulated blood prepared by blending the ratio of blood cells to plasma of defibrinated horse blood (manufactured by NIPPON BIO-TEST LABORATORIES Co., Ltd.) so that the viscosity measured by a B-type viscometer (model TVB-10M manufactured by Toyobo industries Co., Ltd., measurement conditions: spindle No.19, 30rpm, 25 ℃ C., 60 seconds) was 8 mPas was used.

(method of evaluating Friction)

A menstrual sanitary napkin to be evaluated was fixed to menstrual shorts and worn on a dynamic model of a human body. As a dynamic model of a human body, a movable female lumbar model capable of walking movement of both legs is used. A 3-axis tactile sensor (stylochip TS, manufactured by touchhence corporation) was installed in the groin portion of the dynamic model, and the friction with the sanitary napkin at the groin portion was measured within 1 minute from the start of the walking motion. After 1 minute, the walking operation was terminated, and the maximum shearing force during walking was defined as the amount of friction. The smaller the maximum shear force is, the smaller the friction with the sanitary napkin at the groin portion is.

[ Table 1]

As is apparent from table 1, even if the width of the intermediate core portion is narrowed by providing the indented portion, good absorption characteristics can be obtained, and friction can be reduced by providing the indented portion.

Industrial applicability of the invention

According to the pad-type absorbent article of the present invention, friction between the sanitary napkin and the skin can be reduced.

Claims

1. A pad-type absorbent article having an absorbent core, the absorbent core having: a front core portion and a rear core portion located at both end portions in the front-rear direction; and an intermediate core portion located between the front core portion and the rear core portion, the pad-type absorbent article being characterized in that:

a length of the intermediate core portion in a width direction orthogonal to a front-rear direction is shorter than the front core portion and the rear core portion,

the intermediate core has: a high grammage portion located in a widthwise central region and having a higher grammage than the front core portion and the rear core portion; and low grammage parts located in both widthwise side regions and having a lower grammage than the high grammage part,

the high grammage part has: a high grammage and high thickness portion located at a widthwise central portion; and high-grammage low-thickness portions which are located on both sides in the width direction of the high-grammage high-thickness portion, are thinner than the high-grammage high-thickness portion, and have a higher density than the high-grammage high-thickness portion,

the intermediate core portion has a 1 st groove portion having a lower grammage than the low grammage portion in a front-rear direction between the high grammage low thickness portion and the low grammage portion,

the intermediate core portion is formed between a pair of indented regions located at a front-rear direction intermediate portion of the absorbent core,

the absorbent core is covered with a core sheet, and the core sheet is stretched between the front core section and the rear core section at a position further to the outside in the width direction than the side edge section of the center core section, thereby having a retracted section covering section extending from the outer edge section of the center core section to the retracted section region,

the low grammage portion of the intermediate core portion does not have a longitudinal groove portion that divides the low grammage portion in the width direction and has a lower grammage than the low grammage portion,

2. The pad-type absorbent article according to claim 1, wherein:

the dimension in the width direction of the low grammage portion is larger than the dimension in the width direction of the high grammage low thickness portion.

3. The pad-type absorbent article according to claim 1 or 2, wherein:

the high grammage low thickness portion is disposed over the entire length of the intermediate core portion in the front-rear direction.

4. The pad-type absorbent article according to claim 1, wherein:

the absorbent core has a 2 nd groove portion having a lower grammage than the low grammage portion at a boundary between the intermediate core portion and the rear core portion.

5. The pad-type absorbent article according to claim 1, wherein:

the absorbent core has a 2 nd groove portion having a lower grammage than the low grammage portion at a boundary between the front core portion and the intermediate core portion.

6. The pad-type absorbent article according to claim 4 or 5, wherein:

the 2 nd groove part communicates with the 1 st groove part.

7. The pad-type absorbent article according to claim 1 or 2, wherein:

the front core has a tapered portion at a rear end, and the rear core has a tapered portion at a front end.

8. The pad-type absorbent article according to claim 1 or 2, wherein:

the front core portion, the middle core portion, and the rear core portion have a longitudinal groove portion extending in the front-rear direction and a lateral groove portion extending in the width direction.

9. The pad-type absorbent article according to claim 1 or 2, wherein:

the difference between the higher and lower grammage values in the high-grammage and low-caliper portions and the high-grammage and high-caliper portions is within 20% of the value obtained by dividing the difference by the higher grammage value.

10. The pad-type absorbent article according to claim 1 or 2, wherein:

the front core portion has a tapered portion at a rear end, and the rear core portion has a tapered portion at a front end, the tapered portions each having a width that decreases as going toward the middle core portion.

11. The pad-type absorbent article according to claim 1 or 2, wherein:

an absorbent member constituting the absorbent core is not present inside the retracted portion covering section.

12. The pad-type absorbent article according to claim 1 or 2, wherein:

the dimension in the width direction of the high grammage low-thickness portion is smaller than the dimension in the width direction of the retracted portion covering portion.

13. The pad-type absorbent article according to claim 1 or 2, wherein:

the intermediate core is divided into a plurality of blocks by the lateral groove portions.

14. The pad-type absorbent article according to claim 1 or 2, wherein:

the high grammage portion is shaped such that the width thereof gradually decreases in the front and rear portions.

15. The pad-type absorbent article according to claim 1 or 2, wherein:

the high grammage low-thickness portion is not present at the front end portion and the rear end portion of the high grammage portion, and the width of the low grammage portion gradually increases from the middle portion in the front-rear direction of the low grammage portion toward both end portions in the front-rear direction of the intermediate core portion.

16. The pad-type absorbent article according to claim 1 or 2, wherein:

the density of the high gram weight and high thickness part is 0.073g/cm³Above and 0.182g/cm³The following.

17. The pad-type absorbent article according to claim 1 or 2, wherein:

the density of the high gram weight and low thickness part is 0.114g/cm³Above and 0.286g/cm³The following.

18. The pad-type absorbent article according to claim 1 or 2, wherein:

the pad-type absorbent article is a catamenial sanitary napkin.

19. The pad-type absorbent article according to claim 1 or 2, wherein:

the front core and the rear core have a width of 60mm to 100 mm.

20. The pad-type absorbent article according to claim 1 or 2, wherein:

the front core and the rear core have a thickness of 2mm to 7 mm.

21. The pad-type absorbent article according to claim 1 or 2, wherein:

the grammage of the front core part and the rear core part is 90g/m²Above and 300g/m²The following.

22. The pad-type absorbent article according to claim 1 or 2, wherein:

the width of the intermediate core is 35mm or more and 75mm or less.

23. The pad-type absorbent article according to claim 1 or 2, wherein:

the length of the intermediate core in the front-rear direction is 60mm to 180 mm.

24. The pad-type absorbent article according to claim 1 or 2, wherein:

the width of the high-gram-weight low-thickness portion is 2mm to 10 mm.

25. The pad-type absorbent article according to claim 1 or 2, wherein:

the intermediate core portion has a pair of side portions including the low grammage portion positioned on both sides in the width direction of the high grammage portion,

the width of the side portion is 2 times or more and 5 times or less of the width of the high grammage low thickness portion.