TW201628573A - Absorbent article - Google Patents

Abstract

An absorbent article provided with an absorbent body (4) including a long and narrow absorbent core (40) which is long in the front-rear direction of the absorbent article, and is positioned between a non-skin-side sheet (3) for forming a non-skin-facing surface and skin-side sheets (2a, 2b) for forming a skin-facing surface, wherein: the absorbent core (40) is equipped with lateral regions (45) positioned in an excretion section on both sides in the widthwise direction, and a center region (41) which is thicker than the lateral regions (45) and positioned to the center in the widthwise direction relative to the lateral regions (45); the lateral regions (45) and the center region (41) are integrally formed with one another; the center region (41) projects in the direction of the non-skin-side sheet; and a region of the absorbent body (4) where the lateral regions (45) are present when seen from a planar view has a non-joined region not joined to the non-skin-side sheet (3).

Description

Absorbent article

The invention relates to an absorbent article such as a menstrual sanitary napkin, a sanitary pad (vaginal secretion pad), an incontinence pad and the like.

Conventionally, it has been known that an absorbent body of an absorbent article such as a menstrual napkin is provided with a ridge portion so as to follow the uneven shape of the wearer's skin, and it is also known that the ridge portion is formed with a groove. For example, Patent Documents 1 and 2 disclose an absorber having a raised portion having a groove in the vicinity of a central portion of the absorbent body.

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2009-112590

Patent Document 2: Japanese Patent Laid-Open Publication No. 2012-125366

The present invention relates to an absorbent article comprising an absorbent body between a skin side sheet forming a skin facing surface and a non-skin side sheet forming a non-skin facing surface, wherein the absorbent body comprises an absorbent article. An elongated core of elongated shape with a long front and rear direction. The absorptive core body has a side portion located on both sides in the width direction, and a central portion located further in the width direction center side than the side portion and having a thickness larger than the side portion. The side region is integrally formed with the central region, and the central region protrudes toward the non-skin side sheet side. In the absorbent body, the region in which the lateral region is located in a plan view has a non-joining region that is not joined to the non-skin side sheet.

1‧‧‧Sanitary cotton

2‧‧‧Skin side sheet

2a‧‧‧Front sheet

2b‧‧‧Side sheet

3‧‧‧Non-skin side sheet

4‧‧‧Acceptor

5‧‧‧ Central Highlights

6‧‧‧Absorbable ontology

7‧‧‧Flanking

8‧‧‧ rear wing

12‧‧‧The protrusion is adjacent to the high-density part

12'‧‧‧ Both sides in the width direction (the part of the protrusion adjacent to the high-density part)

40‧‧‧Absorbable core

40A‧‧‧Absorbent core

41‧‧‧Central area

41'‧‧‧Central thick-walled area

42‧‧‧High base

42d‧‧‧ forming part of the central projection of the central area

42u‧‧‧ is closer to the skin side than the part of the central protrusion that forms the central area

43‧‧‧Low basis weight

44‧‧‧ transverse slot

44a‧‧‧ transverse slot

44b‧‧‧ transverse slot

44d‧‧‧ bottom

45‧‧‧Side area

45'‧‧‧Side area of the absorber

46‧‧‧High base

47‧‧‧Low basis weight

48‧‧‧Low basis weight

49‧‧‧Low basis weight

50‧‧‧ longitudinal slot

50a‧‧‧ openings

50b‧‧‧ bottom

52‧‧‧ side longitudinal groove

52a‧‧‧ Opening

52b‧‧‧ bottom

53‧‧‧Fiber accumulation device

54‧‧‧Fiber stacking cylinder

55‧‧‧Concave recess

56‧‧‧ bottom

56a‧‧‧ recess

57, 58‧‧‧ Refractory components

59‧‧‧ catheter

61‧‧‧Pressure roller

62‧‧‧ recess

63‧‧‧Smooth roller

A‧‧‧ front section

B‧‧‧Excretion Department

C‧‧‧ Rear

CD‧‧‧ direction orthogonal to the direction of transport

La‧‧‧Width length of the opening

Length of the width of the bottom of Lb‧‧‧

MD‧‧‧Transport direction

R‧‧ Direction

Surface under the S2‧‧‧ lateral area

t‧‧‧The protruding height of the central protrusion

T1‧‧‧ Thickness of the central area

Thickness of the lateral area of t2‧‧‧

W1‧‧‧Width of central projection

W2‧‧‧The entire width of the absorbent core

X‧‧‧ Length direction (front and rear direction)

Y‧‧‧Width direction

Fig. 1 is a perspective view showing a menstrual napkin as a first embodiment of the present invention.

2(a) is a cross-sectional view taken along line IIa-IIa of Fig. 1, and Fig. 2(b) is a cross-sectional view taken along line IIb-IIb of Fig. 1.

Fig. 3 is a plan view showing the absorbent body of the menstrual napkin shown in Fig. 1 from the non-skin facing side.

4(a) and 4(b) are diagrams showing an example of a method of pressing the both side portions of the central thick-walled region to form a density higher than the central projection and having a base weight higher than the lateral region adjacent to the high-density portion. Illustrating.

Fig. 5 is a schematic view showing a state of deformation of the absorbent body of the menstrual sanitary napkin of Fig. 1 in a worn state.

Fig. 6 is a schematic view showing the main part of a fiber stacking device which is preferably used for the manufacture of the absorbent core of the menstrual sanitary napkin shown in Fig. 1.

Fig. 7 (a) and Fig. 7 (b) are schematic views showing a cross section in the circumferential direction of the outer peripheral portion of the fiber stacking cylinder in the fiber stacking device shown in Fig. 6.

The absorbent body of Patent Document 1 has a laminated structure including an upper layer and a lower layer, and a groove penetrating the upper and lower layers is formed in a central portion of the upper layer where the ridge portion is formed. However, the groove is formed by hot embossing, so that the vicinity of the bottom of the groove is compacted, so that there is room for improvement in the flexibility of the wearer's activity.

Further, in Patent Document 2, the absorbing body having a plurality of block-shaped convex portions is similarly provided with a ridge portion including a plurality of convex portions, and the ridge portion easily follows the action of the wearer, but is applied from the wearer side when worn. In the case of strong pressure, there is room for improvement in conformity.

Accordingly, it is an object of the present invention to provide an absorbent article which can improve the performance of the prior art described above.

Hereinafter, the present invention will be described with reference to the drawings based on preferred embodiments thereof.

The menstrual sanitary napkin 1 (hereinafter also referred to simply as the sanitary napkin 1) according to the first embodiment of the absorbent article of the present invention is a night sanitary napkin to be applied at the time of sleeping, preferably having a length of 30 cm or more.

As shown in Fig. 1, the sanitary napkin 1 has an absorbent body 6, a pair of side flap portions 7, 7 and a pair of rear wing portions 8, 8 which are long in the front-rear direction. Regarding absorbent articles such as menstrual napkins, the term "front and rear direction" refers to the direction in which the wearer is in the same direction as the wearer. Further, in the present specification, the front-rear direction is the longitudinal direction, and the direction orthogonal thereto is referred to as the width direction.

The sanitary napkin 1 has a front portion A, a drain portion facing portion B, and a rear portion C in the longitudinal direction thereof, and a pair of side flap portions 7 and 7 on the right and left sides of the absorbent body 6 in the opposing portion B of the drain portion. The left and right sides of the absorbent body 6 in the rear portion C have a pair of rear wing portions 8, 8. In the sanitary napkin 1 (absorbent article) or the absorbent main body 6, the central portion of the excretory portion facing portion B in the width direction is disposed opposite to the body fluid excretion portion of the wearer's vaginal opening, and the front portion A is disposed at the front portion. The excretory portion facing portion B is closer to the front side (ventral side) of the wearer, and the rear portion B is disposed closer to the back side of the wearer than the excretory portion facing portion B.

The sanitary napkin 1 includes a skin side sheet 2 that forms a skin facing surface facing the wearer's skin side when worn, and a non-skin side sheet 3 that forms a non-skin facing surface facing the garment side such as shorts when worn; And an absorber 4 disposed between the two sheets 2, 3. In the present specification, the portion in which the skin side sheet 2, the non-skin side sheet 3, and the absorbent core 40 are overlapped in a plan view is referred to as an absorbent body 6. In the sanitary napkin 1, the skin side sheet 2 is provided with a liquid-permeable front sheet 2a and a pair of side sheets 2b and 2b joined to the both sides. The liquid-permeable front sheet 2a is disposed in the central portion of the absorbent body 6 in the width direction Y so as to extend over the entire length of the absorbent body 6. The side sheet 2b is joined to the front sheet 2a in a state in which the side edge portion 21 on the center side in the width direction of the absorbent main body is superposed on the front sheet 2a, and is joined to the outer side of the side edge portion 21 slightly outward in the width direction. Front sheet 2a. In the sanitary napkin 1, the inner side end portion of the side sheet 2b in the width direction is not along the length direction and the front side. The sheet 2a is joined. Further, in the sanitary napkin 1, an elastic member is not provided at the inner end portion in the width direction of the side sheet 2b. However, an elastic member for forming a body shield may be disposed in the vicinity of the side edge portion 21, and the side edge portion 21 of the discharge portion facing portion B may be caused by the contraction force of the elastic member when worn. A portion of a certain width rises in such a manner as to be separated from the front sheet 2a to form a three-dimensional shield.

The pair of side flap portions 7 and 7 and the pair of rear wing portions 8 and 8 include a side sheet 2b and a non-skin side sheet 3 which are extended from both side edges of the absorbent body 4. In the surface of each of the pair of side flaps 7 including the non-skin side sheet 3, a side flap adhesive portion (not shown) that is fixed to the non-skin opposing surface of the crotch portion of the shorts is provided on the non-skinned body 6 The body facing surface is provided with a body adhesive portion (not shown) for fixing the main body 6 to the inner surface of the shorts. In the sanitary napkin 1, the main body adhesive portion is provided at least in a region overlapping the side region of the absorbent core 4 described below in plan view. The rear wing portion 8 is disposed on the inner surface of the shorts when worn. Preferably, the surface of the rear wing portion 8 including the non-skin side sheet 3 is provided with an adhesive portion for fixing to the inner surface of the shorts. The skin side sheet 2 and the non-skin side sheet 3 are extended to the outside of the peripheral portion of the absorbent body 4, and are joined to each other by an adhesive, and are joined by heat sealing at the peripheral portion of the sanitary napkin 1. . The skin side sheet 2 and the absorbent body 4 and the absorbent body 4 and the non-skin side sheet 3 are joined to each other by an adhesive applied by a pattern such as a dot, a spiral or a stripe. However, the surface of the absorbent body 4 on the non-muscle abutting surface side is in a region where the side portion 45 of the absorbent core 40 is located, and has a non-joining region which is not joined to the non-skin side sheet.

The absorbent body 4 in the sanitary napkin 1 is provided with an elongated core 40 having a longitudinally long shape in the front and rear of the sanitary napkin. The absorbent core 40 includes a fiber assembly including a fiber material such as pulp fibers or a polymer having a highly water-absorptive polymer between fibers of the fiber assembly. Further, the absorber 4 is provided with a core material (not shown) that covers the absorbent core 40. That is, the absorbent core 40 is coated on both the upper and lower sides by a packaged core material (not shown) including a toilet paper or a water-permeable nonwoven fabric. The packaged chip material is used to prevent leakage of the forming material of the absorbent core 40 or to improve the shape retention of the absorbent core 40. The absorbent core 40 is preferably formed by a piece of coated chip material. The cross section of the absorbent core 40 in the width direction is covered over the entire circumference, or the cross section of the absorbent core 40 in the width direction is covered over the entire circumference by a plurality of laminated core sheets. Preferably, for example, the two sides of the rectangular coated chip material disposed on the skin facing surface or the non-skin opposing surface of the absorbent core 40 are folded back to the other side of the absorbent core 40, and laminated on the other side. It is covered on both sides of the other package of the rectangular material of the other side. The portions of the laminate may not be joined, but preferably also follow.

As shown in Fig. 1, the absorbent core 40 in the sanitary napkin 1 has a longitudinally long shape which is long in the same direction as the front and rear directions of the sanitary napkin 1. 2(a) and 2(b), the absorbent core 40 has lateral regions 45 and 45 on both sides in the width direction Y, and a central portion and a thickness larger than the lateral region 45. Central area 41 of 45. In the body region 3 of the body fluid excretion portion of the sanitary napkin 1, the central region 41 has a lower surface S2, S2 than the lateral surfaces 45, 45, and the side of the non-skin side sheet 3, that is, in FIG. The area of the central protrusion 5 that protrudes below.

In the absorbent core 40, the side regions 45, 45 are integrally formed with the central region 41.

In the present specification, the term "integrally formed" means that members which are manufactured in different steps are bonded to each other differently by a bonding method such as an adhesive or compression, and the same material is used and integrally formed in one step. Therefore, at the boundary portion between the central portion 41 and the side regions 45, 45, there is no adjacent portion or joint portion between the core bodies which are generated when the two absorbent core bodies which are separately manufactured are arranged side by side. Further, in the sanitary napkin 1 of the present embodiment, the absorbent core 40 is integrally molded as a whole, so that the portion 42d of the central portion 41 where the central projection 5 is formed and the portion 42u closer to the skin side than the portion 42d are formed. Also, there are no adjacent portions or joints of the layers.

A method of manufacturing an absorbent core of such a configuration will be described below.

The ratio of the width W1 (see FIG. 2(a)) of the central protruding portion 5 to the entire width W2 of the absorbent core 40 is preferably 20% or more, more preferably 30% or more, and further preferably 80%. More preferably, it is 70% or less, and further preferably 20% or more and 80% or less, more preferably 30% or more and 70% or less. Further, in the case where the length of the central protruding portion 5 in the width direction is not fixed, for example, when it is an elliptical or oblong shape, the width W1 of the central protruding portion 5 means the longest length in the width direction. The length of the portion, in contrast to the width, the entire width W2 of the absorbent core 40 is set to the entire width of the same position in the longitudinal direction of the absorbent core 40.

As shown in Fig. 1, the central protruding portion 5 of the absorbent core 40 in the sanitary napkin 1 has a shape elongated in the longitudinal direction of the absorbent core 40, and the rear portion B of the absorbent portion 1 of the sanitary napkin 1 is rearward. Formed as part of Part C. More specifically, it is formed in the range from the vicinity of the front end portion of the opposing portion B of the excretory portion to the vicinity of the central portion of the rear portion C in the X direction.

The center protruding portion 5 is preferably formed in the front and rear direction X of the sanitary napkin 1 (absorbent article) from one portion of the rear portion C from the drain portion facing portion B. Further, the central protruding portion 5 is preferably formed over a length of 30% or more of the entire length of the front and rear directions X of the sanitary napkin 1, and more preferably formed over a length of 40% or more of the entire length of the sanitary napkin 1, and more preferably It is formed over the length of 50% or more of the entire length of the sanitary napkin 1. The same applies to the longitudinal groove 50 and the high density portion 12 described below.

As shown in Fig. 2 (a) and Fig. 3, the non-skin opposing surface of the central region 41 of the absorbent core 40 is formed along the longitudinal direction X of the absorbent core 40 and on the skin facing side. The longitudinal groove 50 at the bottom. In other words, the vertical groove 50 has an opening 50a on the non-skin opposing surface side of the absorbent core 40 and is a groove that does not penetrate the absorbent core 40. In the sanitary napkin 1, the longitudinal grooves 50 are formed by reducing the basis weight of the absorbent material of the absorbent core 40. That is, the longitudinal groove 50 of the sanitary napkin 1 is not formed by partially compressing one of the absorbent cores 40 by embossing or the like. Further, in the sanitary napkin 1, the number of the longitudinal grooves 50 provided in the central protruding portion 5 is one, but the number of the longitudinal grooves provided in the central protruding portion 5 is not limited thereto, and may be intermittent in the width direction Y. Set multiple lines. In the sanitary napkin 1, the vertical groove 50 is disposed so as to traverse the central projection 5 in the longitudinal direction of the central projection 5.

Further, in the central region 41 of the absorbent core 40, a lateral groove 44a is formed in the same manner as the vertical groove 50. The lateral groove 44a is formed by reducing the basis weight of the material for forming the absorbent core 40, and is oriented on the skin. The side has a bottom. In other words, the lateral groove 44a is a groove that has an opening on the non-skin opposing surface side of the central region 41 and that does not penetrate the absorbent core 40, similarly to the vertical groove 50. The lateral groove 44a extends in the width direction Y of the absorbent core 40.

In the sanitary napkin 1 shown in Fig. 1, a plurality of lateral grooves 44a are intermittently provided in the longitudinal direction X in the central portion 41. In the sanitary napkin 1, the lateral groove 44a is provided so as to traverse the central projection 5 in the width direction Y of the central projection 5.

In the central region 41 of the absorbent core 40, as shown in Fig. 2(a), the high basis weight portion 42 and the low basis weight portion 43 forming the bottom portion of the longitudinal groove 50 are alternated in the width direction Y of the absorbent core 40. Formed in the ground, the low basis weight portion 43 extends along the longitudinal direction X of the absorbent core 40. The high basis weight portion 42 is a portion where the basis weight of the material for forming the absorbent core is relatively higher than that of the low basis weight portion 43, and the low basis weight portion 43 is the basis weight and high basis weight of the material for forming the absorbent core. The portion 42 is relatively low compared to the portion.

In the central region 41 of the absorbent core 40, the ratio of the basis weight of the low basis weight portion 43 forming the bottom of the longitudinal groove 50 to the basis weight of the high basis weight portion 42 is preferably 5% or more, more preferably 10%. The above is preferably 80% or less, more preferably 70% or less, further preferably 5% or more and 80% or less, more preferably 10% or more and 70% or less. Further, the basis weight of the high basis weight portion 42 is preferably 200 g/m ² or more, more preferably 300 g/m ² or more, further preferably 800 g/m ² or less, more preferably 700 g/m ² or less. It is preferably 200 g/m ² or more and 800 g/m ² or less, more preferably 300 g/m ² or more and 700 g/m ² or less. The basis weight of the low basis weight portion 43 is preferably 10 g/m ² or more, more preferably 15 g/m ² or more, further preferably 400 g/m ² or less, more preferably 350 g/m ² or less, and further preferably It is 10 g/m ² or more and 400 g/m ² or less, more preferably 25 g/m ² or more and 350 g/m ² or less.

In the central region 41 of the absorbent core 40, the high basis weight portion 42 is not only substantially larger than the low basis weight portion 43 forming the bottom of the longitudinal groove 50, but also thicker than the low basis weight portion 43. Low basis weight 43 The ratio of the thickness to the thickness of the high basis weight portion 42 is preferably 5% or more, more preferably 10% or more, further preferably 50% or less, more preferably 40% or less, and further preferably 5%. The above is 50% or less, more preferably 10% or more and 40% or less. Further, the thickness of the high basis weight portion 42 is preferably 1.5 mm or more, more preferably 2 mm or more, further preferably 10 mm or less, more preferably 8 mm or less, further preferably 1.5 mm or more and 10 mm or less, more preferably It is 2 mm or more and 8 mm or less. The thickness of the low basis weight portion 43 is preferably 0.08 mm or more, more preferably 0.15 mm or more, further preferably 5 mm or less, more preferably 4 mm or less, further preferably 0.08 mm or more and 5 mm or less, more preferably 0.15 mm or more and 4 mm or less.

Further, in the case where the sanitary napkin 1 of the present embodiment includes the lateral grooves 44a to constitute the absorbent core, the high basis weight portion not including the lateral grooves 44a satisfies the value of the high basis weight portion 42 and Each of the values of the relationship of the low basis weights 43 may be sufficient.

(Method for determining the basis weight of high basis weight and low basis weight)

The absorbent core 40 is cut along the boundary line between the high basis weight portion 42 and the low basis weight portion 43 using a single-edged razor manufactured by FEATHER Co., Ltd. to obtain a small piece of the high basis weight portion 42 and the low basis weight portion 43. The portion of the high basis weight portion 42 sandwiched by the side region 45 and the low basis weight portion 43 or the portion sandwiched by the pair of low basis weight portions 43 and 43 is cut into small pieces so as to have a predetermined area. When the small piece includes the low basis weight portion 48 forming the bottom of the lateral groove 44a extending in the width direction Y, the high basis weight portion 42 and the side portion 45, the low basis weight portion 43 or the low basis weight portion 48 are to be used. The portion surrounded by the boundary line is used for measurement in such a manner that the high basis weight portion 42 is cut into small pieces. The small piece of the low basis weight portion 43 is cut in such a manner that the narrow portion between the pair of high basis weight portions 42 and 42 is 30 mm in length. In the case where a small piece having a length of 30 mm which does not include the intersection with the low basis weight portion 48 is obtained as a small piece of the low basis weight portion 43, the length of the intersection portion including the small amount and the low basis weight portion 48 as much as possible is cut to be 30 mm. A small piece is used as a small piece of the low basis weight 43.

The weight of the small pieces was measured using an electronic balance (electronic balance GR-300 manufactured by A&D, precision: 4 digits after the decimal point). Divide the calculated weight by the high basis weight 42 or low base The basis weight of the small piece is calculated from the area of the small piece of the weight 43. Regarding each of the high basis weight portion 42 and the low basis weight portion 43, the average basis weight of the five small pieces is set as the basis weight.

(Method for measuring the thickness of high basis weight and low basis weight)

The measurement of the thickness of the high basis weight portion 42 and the low basis weight portion 43 is performed by measuring the thickness of the small piece cut to measure the basis weight for each portion. An acrylic plate having a size of 20 mm × 20 mm and a thickness of 3 mm was placed in such a manner that its center coincides with the center of the small piece, and a non-contact laser displacement meter (laser LK-G30, displacement meter LK-GD500) manufactured by KEYENCE Corporation was used. Determine the thickness of the sample.

Further, the pressure system at the time of thickness measurement was set to 0.5 g/cm ² . When the size of the cut piece is small and it is difficult to measure by a non-contact type laser displacement meter, the above-mentioned object can also be observed at a magnification of 20 to 100 times using, for example, a microscope (VHX-1000 manufactured by KEYENCE Corporation). The profile of the sample was cut and the measurement was performed.

In the central region 41 of the absorbent core 40, the high basis weight portion 42 has a higher density of the absorbent member than the low basis weight portion 43 forming the bottom of the longitudinal groove 50. Such a configuration is obtained, for example, by pressurizing the central region 41 of the absorbent core 40 in the step of manufacturing the absorbent core 40. At this time, the pressure of the pressurization is concentrated on the thick base portion 42 having a relatively large thickness, and the low basis weight portion 43 having a small thickness is not pressed by the pressurization, and is not compressed. In this manner, only the high basis weight portion 42 is compressed, whereby the high basis weight portion 42 is designed in such a manner that the density of the absorbing member is increased relative to the low basis weight portion 43. Further, in the central portion 41 of the absorbent core 40, the high basis weight portion 42 and the low basis weight portion 48 forming the bottom portion of the lateral groove 44a are alternately formed along the longitudinal direction X of the absorbent core 40. The high basis weight portion 42 also has a higher density of the absorbing member than the low basis weight portion 48 forming the bottom of the lateral groove 44a. Further, the density is calculated by using the basis weight and thickness obtained by the above measurement method.

The basis weight and thickness of the low basis weight portion 48 were measured by cutting a small piece in the same manner as in the case of the low basis weight portion 43. The small piece of the low basis weight portion 48 cuts the narrow portion between the pair of high basis weight portions 42, 42 by a length of 30 mm. Not obtained not included and low In the case of a piece having a length of 30 mm in the intersection portion of the basis weight portion 43, a small piece having a length of 30 mm which is as small as possible at the intersection with the low basis weight portion 43 is cut out and used as a small piece of the low basis weight portion 48. The above-described preferred basis weight ratio, thickness ratio, and the like of the high basis weight portion 42 and the low basis weight portion 43 are also the same between the high basis weight portion 42 and the low basis weight portion 48.

Further, the high basis weight portion 42 having the basis weight difference and the density difference and the low basis weight portion 43 are formed in the above-described manner, whereby the non-skin contrast surface in the central region 5 of the absorbent core 40 is oriented. The longitudinal grooves 50 which are recessed toward the facing side of the skin are formed to extend along the longitudinal direction x of the absorbent core 40, respectively.

In the present specification, the surface of the skin-facing absorbent article or the constituent member thereof that faces the wearer's skin side when worn, and the non-skin-facing facial absorbent article or the constituent member thereof are worn when worn. It is the opposite side of the skin side of the wearer.

Further, in the side region 45 of the absorbent core 40, as shown in Fig. 2(a), the high basis weight portion 46 and the low basis weight portion 47 are alternately formed in the width direction Y of the absorbent core 40, Each of the low basis weight portions 47 extends along the longitudinal direction X of the absorbent core 40. The high basis weight portion 46 has a relatively higher basis weight of the material for forming the absorbent core than the low basis weight portion 47. The low basis weight portion 47 is formed of a material of the absorbent core portion as compared with the high basis weight portion 46. The basis weight is relatively low.

Further, the high basis weight portion 46 having the basis weight difference and the density difference and the low basis weight portion 47 are formed in the above-described manner, whereby the non-skin contrast surface in the side region 45 of the absorbent core 40 is The plurality of side longitudinal grooves 52 that are recessed toward the opposite side of the skin are also formed to extend along the longitudinal direction X of the absorbent core 40, respectively.

In the side region 45 of the absorbent core 40, the high basis weight portion 46 has a higher density of the absorbent member than the low basis weight portion 47 forming the bottom of the longitudinal groove 52. Such a constitution can be obtained in the following manner. The lateral region 45 of the absorbent core 40 is pressurized in a different step than the step of pressurizing the central region 41. The pressure of the pressurization is concentrated on the thick base portion 46 having a relatively large thickness, and the low basis weight portion 47 having a small thickness is not pressed by the pressurization and is not compressed. As such, only the high basis weight portion 46 is compressed, whereby the member is absorbed relative to the low basis weight portion 47. The high basis weight portion 46 is designed in such a manner that the density is increased. Further, the pressurizing step used in this step is performed in such a manner as to use a pressure roller that is dug into a shape corresponding to the central portion 41 or only a side region corresponding to the absorbent core 40. The portion of 45 has a treatment such as a roller of the pressurizing portion, and only the side region of the absorbent core 40 is pressurized.

In the side region 45 of the absorbent core 40, the ratio of the basis weight of the low basis weight portion 47 forming the bottom portion of the side longitudinal groove 52 to the basis weight of the high basis weight portion 46 is preferably 5% or more. It is preferably 10% or more, more preferably 50% or less, more preferably 40% or less, further preferably 5% or more and 50% or less, more preferably 10% or more and 40% or less. Further, the basis weight of the high basis weight portion 46 is preferably 50 g/m ² or more, more preferably 100 g/m ² or more, further preferably 400 g/m ² or less, more preferably 300 g/m ² or less. It is preferably 50 g/m ² or more and 400 g/m ² or less, more preferably 100 g/m ² or more and 300 g/m ² or less. The basis weight of the low basis weight portion 47 is preferably 2.5 g/m ² or more, more preferably 5 g/m ² or more, further preferably 200 g/m ² or less, more preferably 150 g/m ² or less, and further, It is preferably 2.5 g/m ² or more and 200 g/m ² or less, more preferably 5 g/m ² or more and 150 g/m ² or less.

In the lateral region 45 of the absorbent core 40, the high basis weight portion 46 is not only substantially larger than the low basis weight portion 47 forming the bottom of the side longitudinal groove 52, but also thicker than the low basis weight portion 47. The ratio of the thickness of the low basis weight portion 47 to the thickness of the high basis weight portion 46 is preferably 5% or more, more preferably 10% or more, further preferably 50% or less, more preferably 40% or less, and It is preferably 5% or more and 50% or less, more preferably 10% or more and 40% or less. Further, the thickness of the high basis weight portion 46 is preferably 0.8 mm or more, more preferably 1 mm or more, further preferably 5 mm or less, more preferably 4 mm or less, further preferably 0.8 mm or more and 5 mm or less, more preferably It is 1 mm or more and 4 mm or less. The thickness of the low basis weight portion 47 is preferably 0.04 mm or more, more preferably 0.08 mm or more, further preferably 0.4 mm or less, more preferably 0.32 mm or less, and further preferably 0.04 mm or more and 0.4 mm or less. More preferably, it is 0.08 mm or more and 0.32 mm or less.

Further, in the case where the sanitary napkin 1 of the present embodiment includes the lateral groove 44b to constitute the absorbent core, the high basis weight portion not including the lateral groove 44b is only required to conform to the above-described high basis weight portion. The values of 46 and the relationship with the low basis weight portion 47 may be used.

Further, the method of measuring the basis weight and the thickness of each of the high basis weight portion 46 and the low basis weight portion 47 is performed in the same manner as the measurement method of the high basis weight portion 42 and the low basis weight portion 43.

Further, the high basis weight portion 42 in the central portion 41 where the central protruding portion 5 is located has a larger basis weight than the high basis weight portion 46 of the side portion 45, and the base portion 46 is higher than the side portion 45. In comparison, the thickness also becomes larger. Thereby, the thickness t1 of the central portion 41 is thicker than the thickness t2 of the side region 45, and the central portion 41 is formed with the central projection 5 projecting to the lower surface S2 of the lateral side region 45.

The ratio of the thickness t1 of the central region 41 to the thickness t2 of the lateral region 45 is preferably 110% or more, more preferably 120% or more, further preferably 400% or less, more preferably 300% or less, and further, Preferably, it is 110% or more and 400% or less, more preferably 120% or more and 300% or less. Further, in the present embodiment, the thickness t1 of the central portion 41 is the above-described thickness of the high basis weight portion 42 located at the central portion in the width direction of the central portion 41, and the thickness t2 of the side portion 45 is the closest to the central portion 41. The above thickness of the basis weight portion 46. When the protrusion portion is adjacent to the high-density portion 12 in the side region 45, the thickness of the high basis weight portion 46 which is closest to the protrusion portion adjacent to the high-density portion 12 is set.

Regarding the central protruding portion 5, the ratio of the height t protruding from the lower surface S2 of the side portion 45 to the entire thickness t1 of the central portion 41 is preferably higher in each of the opposing portion B and the rear portion C of the drain portion. It is 20% or more, more preferably 30% or more, further preferably 90% or less, more preferably 80% or less, further preferably 20% or more and 90% or less, more preferably 30% or more and 80% or less. the following. The protruding height t of the central projection 5 is the same as the value obtained by subtracting the thickness t2 of the lateral region 45 from the entire thickness t1 of the central portion 41.

In the sanitary napkin 1, in the side region 45, the high basis weight portion 46 and the low basis weight portion 49 are alternately formed in the longitudinal direction X of the absorbent core 40, and each of the low basis weight portions 49 is also along the absorbent core. The width direction Y of the body 40 extends. Thereby, in the side area 45, the plurality of lateral grooves 44b are intermittently arranged in the longitudinal direction X. The low basis weight portion 48 and the side area 45 of the central portion 41 The low basis weight portion 49 is at the boundary portion between the central portion 41 and the side portion 45, and the position of the longitudinal direction X of the absorbent core 40 coincides. Similarly, the lateral groove 44a of the central portion 41 and the lateral regions 45, 45 The lateral grooves 44b are at the boundary portion, and the positions of the longitudinal direction X of the absorbent core 40 coincide with each other.

In other words, when the lateral groove 44a of the central region 41 and the lateral grooves 44b of the lateral regions 45 and 45 are viewed from the non-skin opposing surface side, the central portion 41 of the self-absorbent core 40 is formed over the side. The square regions 45, 45 are continuous with one transverse groove 44 extending over the entire width of the absorbent core 40. Further, the lateral grooves 44 are formed in plural at intervals in the longitudinal direction of the absorbent core 40. In other words, the low basis weight portion 43 of the central region 41 and the low basis weight portion 47 of the side region 45 form a low basis weight portion extending continuously throughout the entire width of the absorbent core 40, the absorption of the one low basis weight portion The basis weight, thickness, and density of the forming material of the core body are smaller than the high basis weight portion 46 of the side region 45.

Regarding the lateral groove 44, the continuous region from the central region continuously means that when the absorbent core 40 is viewed from the non-skin opposing surface side, the lateral groove is not interrupted between the central region and the lateral region, and the central region is interrupted. It exists continuously throughout the side area. In the sanitary napkin 1 of the present embodiment, the lateral groove 44 and the vertical groove 50 intersect in a cross shape in a plan view, but there is another cross in the extension of the space in the lateral groove on one side with respect to the longitudinal groove. In the case of all or part of the space in the slot, the lateral slot is not interrupted at the intersection with the longitudinal slot.

The absorbent body 4 in the sanitary napkin 1 has a region 45' (hereinafter also referred to as a side region 45' of the absorbent body) in which the side region 45 of the absorbent core 40 is located in a plan view, and has no joint with the non-skin side sheet 3. Non-joining area. On the other hand, the absorbent body 4 is joined to the non-skin side sheet 3 in a region 41' (hereinafter also referred to as a central region 417 of the absorbent body) in which the central protruding portion 5 of the absorbent core 40 is placed in a plan view. Therefore, as shown in FIG. 2(a), a space is formed between the absorbent core 40 and the non-skin side sheet 3 in the side region 45' of the absorbent body 4. In the case where the absorptive core 40 is covered with the core material, the space may be formed between the absorbent core and the packaged core material, or may be formed between the packaged core material and the non-skin side sheet 3, Good for the package of chip A space is formed between the non-skin side sheet 3. In this case, the absorbent core 40 and the packaged core material may or may not be attached. The surface of the absorbent core 40 on the non-skin facing side may also be followed by a pattern-coated adhesive and a coated core material throughout the entire area. Further, the surface of the absorbent core 40 on the abutting surface side may be followed by the pattern-coated adhesive and the coated core material throughout the entire area.

In the sanitary napkin 1, there is a non-joining region throughout the widthwise direction of the lateral region 45' of the absorbent body 4 located outside the width direction of the region in which the central projection 5 is located, in Fig. 2(a), the side The square region 45' overlaps with the non-joining region. However, the present invention is not limited thereto, and a portion of the region 45' where the side region 45 of the absorbent body 4 is located in the plan view may be joined to the non-skin side sheet 3. For example, a form in which only the position of the end edge in the width direction of the absorbent core 40 is joined to the non-skin side sheet may be mentioned. Moreover, the entire region of the side region 45' located in the opposing portion B of the excretion portion may be a non-joining region, and the lateral portion 45' of the absorber 4 may be provided in the front portion A or the rear portion C. The portion of the non-skin side sheet 3 joined. In the case where the central protruding portion 5 has a shape in which the width is not uniform, such as an oblong shape, the central protruding portion 5 is located on the inner side in the width direction of the front side or the rear side in the longitudinal direction of the maximum width portion of the central protruding portion 5. The square region 45', the side region 45' of the absorbent body 4 is joined to the non-skin side sheet 3, and the non-joining region is formed in a region outside the imaginary line extending from the maximum width portion before and after the longitudinal direction X. . However, it is preferable that at least the entire region of the region 45' where the lateral region 45 in the opposing region B of the body fluid excretion portion is formed is a non-joining region that is not joined to the non-skin side sheet 3.

In the absorbent article of the present invention, the absorbent core 40 is integrally formed with the central region 41 and the side region 45, and the central projection 5 of the central portion 41 having a relatively thick thickness protrudes toward the non-skin side sheet 3 side. Further, the side region 45' of the absorber 4 located further outward in the width direction than the center projecting portion 5 is provided with a non-joining region where the absorber 4 and the non-muscle sheet 3 are not joined. Therefore, a unique effect as explained below can be obtained.

First, when the wearer wears the absorbent article of the present invention, the row of absorbent articles The peripheral portion of the venting portion of the venting portion is deformed in such a manner as to follow the shape of the body. At this time, the peripheral portion 5 has a buffering pressure region or space on the non-skin opposing surface side by the central protruding portion 5 that protrudes away from the wearer's skin. Therefore, the side regions 45' and 45' of the absorbent body 4 have a cushioning region between the crotch portion and the central region 41', and are bent, so that a deformed shape having excellent cushioning properties can be formed (see Fig. 5).

In the sanitary napkin 1 shown in Fig. 2(a), the region of the cushioning pressure is a space formed between the lateral region 45' of the absorbent body 4 and the non-skin side sheet 3. In particular, when the sanitary napkin 1 is worn, when the force is applied from the skin facing side to the non-skin facing side, the side area 45' is bent and moved toward the non-skin opposing surface, but the side is The area adjacent to the central protrusion 5 in the square area 45' easily maintains the space between the side area 45' and the non-skin side sheet 3. Further, in the sanitary napkin 1 of the present embodiment, a longitudinal groove and a lateral groove are formed in the central portion 41 and the side region 45 of the absorbent core 40, and the pressure applied in the width direction of the product can be further alleviated.

Further, the buffer region can be formed to maintain the space between the central projection 5 and the side region 45', so that a ventilating passage is formed in a region close to the central region 41 where the absorption capacity is large and a large amount of excretion liquid is maintained, and Can reduce the feeling of dampness.

Further, the central protruding portion 5 that protrudes toward the skin-side sheet 3 side functions as a cushion, and is stronger from the opposite side of the skin toward the non-muscle direction, for example, after the excretion liquid is absorbed by the absorbent article. The pressure is applied to the absorbent article by the body fluid discharge portion of the wearer, and the pressure can be softly received. Further, the space of the central protruding portion 5 can be secured by the buffer region, so that the wearer can feel soft and wearable. And it is possible to suppress leakage of excretion liquid from the central absorption portion 5.

These effects are particularly good when the absorbent article is in the case of a sanitary napkin, which imparts a gentle touch to the sensitive vaginal opening or its vicinity. In the case where the non-skin side sheet 3 is provided with an absorbent article such as a panty or the like, since the non-joining region of the side region 45 and the non-skin side sheet 3 is present, the absorbent core 40 is provided. Not susceptible to The advantages of the above effects are outstanding because of the influence of wrinkles or wrinkles such as underwear. The advantage of this effect is particularly advantageous when the above-described fixing mechanism is provided on the non-skin abutting surface in the opposing portion of the side portion of the non-skin side sheet.

Further, in the absorbent core 40 of the sanitary napkin 1 of the present embodiment, the protruding portion is adjacent to the high-density portion 12, and the protruding portion is adjacent to the central portion 41 of the high-density portion 12 and the side regions 45, 45 and The density is higher than the central area 41. The density of all the constituent materials of the fibers forming the absorbent core, the absorbent polymer, and the like, in comparison with the high-density portion 12 of the central portion 41 and the high-density portion 42 having no longitudinal grooves and lateral grooves in the central region 41. It means that the high basis weight portion 42 is relatively low in density compared to the protrusion portion adjacent to the high density portion 12.

Further, in the sanitary napkin 1, the side region 45 having a lower basis weight and a lower density than the high-density portion 12 adjacent to the protruding portion is disposed on the outer side of the protruding portion adjacent to the high-density portion 12 in the width direction. .

When the protrusion portion is adjacent to the high-density portion 12 by the method shown in FIG. 4, the density on the non-skin opposing surface side is higher than the density on the opposite surface side of the skin, but the density of the protrusion portion adjacent to the high-density portion 12 is The measurement was carried out by cutting the entire thickness direction of the absorbent core.

The density of the protrusions adjacent to the high-density portion 12 is 110% or more, preferably 120% or more, and more preferably 400% or less with respect to the high-basic portion 42 of the central portion 41 having no longitudinal grooves and lateral grooves. More preferably, it is 300% or less, and further preferably 110% or more and 400% or less, more preferably 120% or more and 300% or less.

Further, the density of the protrusion adjacent to the high-density portion 12 is 150% or more with respect to the density of the side portion 45, preferably 160% or more, more preferably 500% or less, still more preferably 400% or less, and further, Preferably, it is 150% or more and 500% or less, more preferably 160% or more and 400% or less.

[Method of calculating the density of the central area]

In the absorbent core 40, a single-edged razor manufactured by FEATHER Co., Ltd. was used to cut the width direction of the product by 3 mm and in the longitudinal direction of the product so as to have a predetermined area. It is a test piece of 30 mm in size. First, the test piece of the high base portion 42 having no longitudinal grooves and lateral grooves in the central portion 41 was cut out, and the mass was measured using an electronic balance (electronic balance GR-300 manufactured by A&D, accuracy: 4 decimal places). . Next, the cross section of the cut sample is observed at a magnification of 20 to 100 times using, for example, a microscope (KEYENCE VHX-1000), and the thickness is measured. Further, the number of test pieces to be measured was set to five, and the average value was set to the thickness of the central region. The density measured in the central region was calculated by dividing the mass measured above by the volume of the test piece (thickness × length in the product width direction × length in the product longitudinal direction).

[Method for calculating the density of the protrusion adjacent to the high density portion]

A test piece having a width of 3 mm in the product width direction and a length of 30 mm in the longitudinal direction of the product was continuously cut into a plurality of pieces from the center of the product in the width direction of the absorbent article (product), and an electronic balance was used (A&D Co., Ltd.) The manufactured electronic balance GR-300, accuracy: 4 digits after the decimal point) was measured for its quality. Next, the cross section of the cut sample is observed at a magnification of 20 to 100 times using, for example, a microscope (VHX-1000 manufactured by KEYENCE Corporation), and the thickness is measured.

Further, each of the cut test pieces was cut out from five absorbent articles, and the test piece to be measured was set to the same portion of each of the five absorbent cores 40, and the average value was defined as the thickness of the test piece. The mass measured above was divided by the volume of the test piece (thickness × length in the product width direction × length in the product longitudinal direction), and the density of the test piece cut from each part was calculated.

Each of the obtained test pieces was subjected to a test piece cut out from the center side of the product, and the test piece on the center side in the width direction of the product and the test piece cut out from the portion adjacent to the outer side in the width direction of the test piece were sequentially calculated. In the density ratio (the former/the latter), when the density ratio is 0.5 or less, the density of the test piece on the outer side in the width direction of the product in the two test pieces is defined as the density of the protrusion adjacent to the high-density portion 12.

In the sanitary napkin 1 of the present embodiment, as shown in FIG. 4, when the protruding portion is adjacent to the high-density portion 12 for manufacturing the sanitary napkin, the central portion 41 of the absorbent core 40 is formed to be a high basis weight portion. A portion 42' of the same thickness 42 is formed by compressing both side portions 12' in the width direction. Since the central region 41 has such a configuration, the following effects are exhibited.

First, when the pressure from the wearer is applied to the opposing portion of the excretion portion, the protrusion portion is deformed against the high-density portion 12, so that the lateral region 45 of the absorbent core 40 is easily formed on the central projection portion 5. The space is deformed while maintaining a space with the side portion 45. Therefore, the effects of the present invention described above are further easily exerted.

Moreover, this configuration is also advantageous for absorption performance. First, the body fluid of the opposing portion B is discharged to the central protruding portion 5 of the central region 41. On the side portion of the central portion 41, a projection portion formed by compressing the central projection portion 5 is adjacent to the high-density portion 12. Therefore, the body fluid diffused in the width direction Y and the thickness direction is guided to the high density portion. The protrusions are adjacent to the high-density portion 12 because the basis weight of the absorbent material is higher than that of the side regions 45, so that the ability to hold the body fluid is high. Therefore, the body fluid is blocked at both side portions of the central portion 41, and it is difficult to reach both sides in the width direction of the sanitary napkin 1. Therefore, in the sanitary napkin 1, it is easy to suppress the side leakage of the body fluid.

The protrusion portion is adjacent to the high-density portion 12 and will be described more specifically.

The protrusion in the sanitary napkin 1 is adjacent to the high-density portion 12, and after the absorbent core 40A shown in Fig. 4(a) is produced by using the fiber stacking device shown in Fig. 6 as the main portion, the absorbent core 40A is attached. The both sides of the central thick-walled region 41' are compressed and formed, and the absorbent core 40A has a thick central portion 41' which is formed to be a thick portion of the portion 12' of the high-density portion 12. In the sanitary napkin 1, the fixed portion of the left and right sides of the central thick portion 41' which is located at the central protruding portion is compressed, whereby the thickness is reduced, and the portion is formed with the protruding portion adjacent to the high-density portion 12. As a region where the density is higher than the uncompressed central projection 5. Further, since the protruding portion is adjacent to the other portion of the side portion 45 and the high-density portion 12 has a higher basis weight of the absorbent material, it has a sufficient absorption capacity, so that the body fluid is prevented from reaching the side edge of the absorbent core 40. Therefore, it is easy to prevent the body fluid from leaking from the side of the sanitary napkin 1. In the sanitary napkin 1 of the present embodiment, the protrusion portion adjacent to the high-density portion 12 has substantially the same thickness as the portion of the side portion 45 where the vertical groove 50 and the lateral groove 44 are not present. However, the present invention is not limited thereto, and may be a protrusion. The thickness of the portion adjacent to the high density portion 12 is thinner than the central protrusion portion 5, However, it is thicker than the side area 45.

Further, in the sanitary napkin 1, the longitudinal groove 50 of the central projecting portion 5 has a narrower length in the width direction of the bottom portion 50b than the opening portion 50a. More specifically, as shown in FIGS. 2( a ) and 2 ( b ), the lengthwise direction of the longitudinal groove 50 of the central protruding portion 5 gradually narrows from the opening portion 50 a toward the bottom portion 50 b in the width direction. In the cross-sectional view, the vertical groove 50 has a substantially inverted V shape from the non-skin opposing surface side toward the skin facing surface side. In addition to the above-described form, the shape may be a stepped cross-sectional shape. However, when the pressure is applied to both outer sides in the width direction in a substantially inverted V shape, the non-skin opposing surface of the central portion 41 is largely deformed, and the skin is facing. Since the amount of surface deformation is small, the absorption area at the opposite portion of the excretion portion is not reduced, and a feeling of softness can be obtained. This effect is particularly effective when the protrusion portion is adjacent to the high-density portion 12.

The length La of the opening 50a of the vertical groove 50 of the central protruding portion 5 in the width direction is preferably 0.5 mm or more, more preferably 1 mm or more, further preferably 5 mm or less, further preferably 4 mm or less, and the width of the bottom portion 50b. The direction length Lb is preferably 1 mm or less, and more preferably 0.5 mm or less. The lower limit of the width direction length Lb of the bottom portion 50b is 0 (zero).

Further, the depth of the vertical groove 50 is preferably 0.5 mm or more and 5.0 mm or less, and more preferably 1.0 mm or more and 3.0 mm or less. Further, the difference between the length of the opening 50a of the vertical groove 50 and the length of the bottom portion 50b (the above-mentioned La-Lb) is preferably 0.5 mm or more and 3 mm or less, and more preferably 1 mm or more and 2 mm or less.

Further, the ratio of the depth of the vertical groove 50 to the difference in the width direction of the opening portion 50a and the bottom portion 50b (the above-described La-Lb) (depth/difference (La-the above-mentioned Lb)) is preferably 0.5 or more and 20 or less. Further, it is preferably 1 or more and 10 or less. If it is this range, the shape of the longitudinal groove in wear is easy to stabilize, and it is easy to maintain the preferable shape for absorbing excrement.

Further, the bottom portion 50b of the longitudinal groove 50 is located below the lower surface S2 of the side portion 45. The position of the lower surface S2 of the side area 45 mentioned here is the lower surface of the high basis weight 46 in the portion of the side area 45 adjacent to the central area 41. The bottom 50b of the longitudinal groove 50 is preferably In the longitudinal direction X of the absorbent core 40, the entire area of the central region 41 is located further below the lower surface S2 of the lateral region 45. With such a configuration, it is easy to suppress excessive deformation of the sanitary napkin during wearing, and it is easy to bring about an appropriate feeling of wearing.

Further, each of the central region 41 and the lateral region 45 of the absorbent core 40 has a lateral groove and a longitudinal groove, so that the non-skin opposing surface has a concave-convex shape, and on the other hand, the skin is facing The surface becomes flat.

According to the sanitary napkin 1 of the present embodiment, the central portion 42 having the central projection 5 is formed with a lateral groove 44, the lateral groove 44 is shallow, and the bottom portion 44d reaches the lower surface S45 and is closer to the non-skin. The position of the side surface also extends from the central portion 42 to the side portion 45, and the lateral groove 44 is formed by reducing the basis weight of the material for forming the absorbent core, and therefore has a central projection which is generally susceptible to bending. 5, but it is deformable, and it is not easy to wrinkle on the opposite side of the skin of the sanitary napkin 1. Therefore, as shown in FIG. 5, the absorbent body 4 and the non-skin opposing surface of the sanitary napkin 1 including the same can follow the body fluid discharge portion or the gluteal groove of the wearer, and the overall shape can follow the shape of the wearer. The method is deformed, and is excellent in conformability with respect to the unevenness of the body, and is excellent in followability with respect to the wearer's activity, and is also less likely to cause discomfort due to wrinkles or bending of the absorbent core.

With regard to this effect, when the entire area of the bottom portion 44d of the lateral groove 44 over the central portion 41 of the width direction Y of the absorbent core 40 is located further below the lower surface S2 of the side portion 45, it is further improved.

From the viewpoint of more effectively exerting such an effect, the ratio of the depth of the lateral groove 44a (44) of the central portion 41 to the thickness t1 of the central portion 41 is preferably 50% or more, more preferably 60% or more, and further It is preferably 95% or less, more preferably 90% or less, further preferably 50% or more and 95% or more, more preferably 60% or more and 90% or less.

Further, the width W of the lateral groove 44 is preferably 0.2 mm or more, more preferably 0.5 mm or more, further preferably 3 mm or less, more preferably 2 mm or less, and further preferably 0.2 mm or more and 3 Below mm, it is more preferably 0.5 mm or more and 2 mm or less. As shown in Fig. 1, the width W of the lateral groove 44 is the dimension of the longitudinal direction X of the absorbent core.

Further, in the sanitary napkin 1, the density of the high basis weight portion 42 of the central portion 41 is higher than that of the low basis weight portion 43, so that the body fluid absorbed through the lateral groove 44 is quickly absorbed into the high basis weight portion 42. Therefore, the body fluid is absorbed in the longitudinal direction of the absorbent core 40 along the lateral groove 44, so that the body fluid absorption in the central region 41 can be efficiently performed. As a result, the suppression of the liquid leakage of the self-absorbent core 40 is improved. In addition to this, in the side region 45, the density of the high basis weight portion 46 is also higher than that of the low basis weight portion 47, so that the same effect can be obtained.

In each of the central region 41 and the side region 45, the ratio of the density of the low basis weight portion to the density of the adjacent high basis weight portion is preferably 5% or more, more preferably 10% or more, and further preferably 50% or less, more preferably 40% or less, further preferably 5% or more and 50% or less, more preferably 10% or more and 40% or less.

Further, in the sanitary napkin 1, a side vertical groove 52 extending in the longitudinal direction is also provided in the side region 45. The side longitudinal groove 52 has substantially the same length in the width direction Y of the opening portion 52a on the skin facing surface side and the bottom portion 52b on the non-skin opposing surface side. Here, "substantially the same" means that the difference in the width direction between the opening portion and the bottom portion at the same position in the longitudinal direction is within 5%. With this configuration, the sanitary cotton 1 is uniformly transmitted to the side longitudinal grooves 52 by the compressive force received from the user's leg during wearing, and the lateral longitudinal grooves 52 are uniformly compressed, so that the user can relax the sanitary napkin. 1 The reaction of the compression force can eliminate the discomfort felt by the user when wearing the sanitary napkin 1. Further, when the opening 52a of the side vertical groove 52 is formed to be larger than the bottom portion 52b, the sanitary napkin 1 has a larger compression force due to the compressive force received from the base of the user's leg during wearing. The deformation is such that the side edge portion of the sanitary napkin 1 is deformed in such a manner as to collapse toward the user. In this deformation, the side edge of the sanitary napkin 1 is warped toward the skin side of the user, so that the sanitary napkin 1 strongly abuts against the groin portion or the skin of the user of the central portion of the sanitary napkin 1 and the surface of the sanitary napkin 1 The interval is generated. However, by making the lengths of the opening portion 52a and the bottom portion 52b substantially the same in the width direction, It can reduce the risk of such an adverse situation. Moreover, it also contributes to the stability of the shape of the longitudinal groove 50 of the central portion 41 in the present invention.

The side longitudinal grooves 52 are preferably adjacent to the protrusions adjacent to the high density portion 12. With such a configuration, the hardness of the absorbent core 40 that is in contact with the side of the side longitudinal groove 52 and the absorbent core 40 that is in contact with the center side of the side longitudinal groove 52 are different depending on the difference in hardness. The sanitary napkin 1 is easy to bend the side edge portion in the opposite direction to the skin of the user with the side longitudinal groove 52 as a base axis, so that the shape of the wearing sanitary napkin 1 is more stable, thereby reducing the wearing of the sanitary napkin 1 The user feels uncomfortable, and the central portion of the sanitary napkin 1 can be more closely adhered to the skin of the user, and the liquid can be absorbed more efficiently. Further, the high-density portion that functions to absorb and trap the liquid is adjacent to the side longitudinal groove 52 having a relatively low density, and the effect is that the liquid is prevented from oozing out to the side of the higher-density portion. The liquid is fixed in an area closer to the central portion of the sanitary napkin 1 to prevent liquid from leaking from the side edges of the sanitary napkin 1.

Preferably, the bottom surface 50a of the longitudinal groove 50 of the central portion 41 is located on the non-skin opposing side of the bottom surface 52a of the lateral longitudinal groove 52. With such a configuration, first, the side surface of the longitudinal groove 50 on the side opposite to the non-skin facing surface is used as the base axis, and the side portion of the sanitary napkin 1 is bent in the opposite direction to the skin of the user, and secondly, the bottom surface is located further. The side longitudinal groove 52 on the opposite side of the skin is the base axis, and the side portion of the sanitary napkin 1 is bent in the opposite direction to the skin of the user, so that the shape of the sanitary napkin 1 in use can be made more stable.

The absorbent core 40 of the sanitary napkin 1 can be manufactured, for example, by manufacturing the absorbent core 40A using the fiber stacking device 53 (see FIG. 6), and the fiber stacking device 53 is provided. The fiber stacking cylinder 54 is provided with a collecting recess 55 on the outer peripheral surface and rotated in one direction R, and a duct 59 that supplies the material for forming the absorptive core to the outer peripheral surface of the fiber stacking cylinder 54 in a scattered state. In FIG. 4, the absorbent core 40A having the central thick-walled region 41' in the central portion of the direction CD orthogonal to the transport direction MD is introduced to a pressure roller having a concave portion 62 at one of the circumferential surfaces. 61 is strongly adjacent to the smoothing roller 63 having a smooth surface, and is partially adjacent to the central region 41. The portion 12' is pressed to form an absorbent core 40 having a projection adjacent to the high-density portion 12. 4, the case where the central portion 41 is formed as the central portion 41 is not pressurized, but it may be any of the portion which becomes the central portion 41 and the portion which becomes the lateral region 45 or Both of them are pressure-compressed weaker than the portion 12' where the protrusion is adjacent to the high-density portion 12.

The accumulation recesses 55 in the fiber stacking device 53 shown in Fig. 6 are formed at a fixed interval along the circumferential direction of the outer peripheral surface of the fiber stacking cylinder 54 at a fixed interval. The bottom surface 56 of the collecting recess 55 includes a mesh plate or the like and has a plurality of micro holes that function as suction holes.

As shown in Fig. 7(a), a recess 56a for forming the central thick-walled region 41' is formed in a portion of the bottom surface 56 of the accumulation recess 55. At the bottom of the collecting recess 55, the gas-impermeable members 57, 58 for forming the low basis weight portions such as the low basis weight portions 43, 48 are disposed. The gas-impermeable members 57 and 58 are fixed so as to protrude from the bottom surface of the collecting recess 55, and may be a non-breathable member or may contain, for example, metal or plastic.

In the same manner as the well-known fiber stacking device including the fiber stacking cylinder, the material for the absorbent core is supplied to the inside of the duct by suction from the bottom surface of the collecting recess 55, as shown in Fig. 7(b). The material for forming the absorbent core is deposited in a specific shape in the collecting recess 55. The absorbent core 40A is obtained by demolding the deposit 4' from the collecting recess 55. The absorbent core 40A may be pressurized and moderately compressed by a pair of rolls or the like before or after being coated with a clad material. As shown in Fig. 7(b), the portion including the core forming material deposited on the gas-impermeable members 57 and 58 is a low basis weight portion 43 or the like, and is deposited on the bottom surface of the gas-impermeable members 57 and 58. The part becomes the high basis weight 42 and the like. Further, as described above, by pressing the central portion 41 of the absorbent core 40A, a high basis weight portion 42 having a higher density than the low basis weight portion 43 is formed in the central portion 41, and becomes a central portion 41. The portions partially pressurize the side regions 45 separately, while the side regions 45 form a higher basis weight portion 46 having a higher density than the lower basis weight portions 47. Further, the central thick-walled region 41' of the absorptive core 40A may be formed before or after being coated with the packaged core material. The starting portion is adjacent to the pressurization (compression) of the high density portion 12. The pressurization (compression) in which the protrusion portion is adjacent to the high-density portion 12 may be performed simultaneously with the press of the step having a step on the circumferential surface and the central portion 41, or may be performed simultaneously with the pressurization of the side region 45. Further, by designing the step formed on the circumferential surface of the roller to an appropriate size, it can be performed simultaneously with the pressurization of the central portion 41 and the pressurization of the side region 45. Further, the pressurization of the central portion 41 and the pressurization of the side region 45 may be performed in different steps, or before the pressurization of the central region 41, the pressurization of the central region 41, and the pressurization of the lateral region 45. After the pressurization of the side region 45, the pressurization is performed in different steps. In the case of producing an absorbent core comprising a water-absorptive polymer, it is preferred to provide an introduction portion of the water-absorbent polymer in the middle of the conduit.

As the front sheet 2a and the non-skin side sheet 3, the same as those previously used in the technical field can be used without particular limitation. For example, as the front sheet 2a, a non-woven fabric or a perforated film having liquid permeability can be used. As the non-skin side sheet 3, a liquid impervious film made of a synthetic resin or a non-woven fabric having a high water pressure resistance such as a spunbond-meltblown-spunbonded nonwoven fabric can be used. Further, as the side sheet 2b, a water-repellent non-woven fabric having a high water pressure resistance, for example, a spunbond-melt-spray-spun layer non-woven fabric or the like can be used.

Hereinabove, the present invention has been described based on preferred embodiments thereof, but the present invention is not limited to the above embodiments.

For example, in the side region 45, either or both of the lateral lateral grooves 44b and the lateral longitudinal grooves 52 may not be present. Further, either or both of the lateral lateral grooves 44b and the lateral longitudinal grooves 52 may be formed on the skin facing surface side of the absorbent core 40.

Moreover, the lateral groove 44 which is continuous from the central region 41 and the side region 45 may be formed only in the opposing portion of the excretion portion of the absorbent article, or may be formed only in the rear portion.

Further, the absorbent core may include only a fibrous material such as pulp fibers, or may include both a fibrous material and a superabsorbent polymer. As the fibrous material, various fibrous materials previously used for an absorbent body of an absorbent article such as a sanitary napkin or a sanitary pad or a disposable diaper can be used without particular limitation, and for example, fibers such as pulp fibers, rayon fibers, and cotton fibers can be used. Short fibers of plain fibers, short fibers of synthetic fibers such as polyethylene, and the like. These fibers may be used alone or in combination of two or more. Further, the fiber material is preferably a whole or a part of pulp fibers, and the ratio of the pulp fibers in the fiber material is preferably from 50 to 100% by mass, more preferably from 80 to 100% by mass, even more preferably from 100% by mass. Further, in addition to the superabsorbent polymer, a deodorant or an antibacterial agent may be blended as needed for the absorbent core.

Further, in the above embodiment, the density of the high basis weight portion is higher than that of the low basis weight portion, but the density of the both may be the same by omitting the pressing step of the absorbent core.

Moreover, the absorbent article of the present invention may be a sanitary pad (vaginal secretion pad), an incontinence pad, a disposable diaper, or the like, in addition to the menstrual napkin. The description of the above-described embodiments and the necessary conditions of only one embodiment can be appropriately applied to other embodiments, and the necessary conditions in the respective embodiments can be replaced with each other as appropriate.

In the above embodiment, the present invention further discloses the following absorbent article.

<1> An absorbent article comprising an absorbent article comprising an absorbent body between a skin side sheet forming a skin facing surface and a non-skin side sheet forming a non-skin facing surface, wherein the absorbent body comprises absorption along the absorbent body a longitudinally elongated absorbent core having a longer longitudinal direction, wherein the absorbent core has a lateral portion on a side opposite to the width direction and a central portion on the side opposite to the side The square region is further located on the center side in the width direction and has a thickness larger than the side region; the lateral region is integrally formed with the central region, and the central region protrudes toward the non-skin side sheet side, and the absorbent body is viewed from above. The region in which the lateral region is located has a non-joining region that is not joined to the non-skin side sheet.

<2> The absorbent article according to the above <1>, wherein a portion of the side region adjacent to the central region has a high density portion having a higher density than the central region.

<3> The absorbent article according to the above <1> or <2>, wherein the non-skin opposing side of the central region is formed along the length of the absorbent core and on the skin In the vertical groove having the bottom portion on the facing surface side, the length of the bottom portion in the width direction is narrower than the opening portion.

<4> The absorbent article according to the above <3>, wherein the longitudinal direction of the longitudinal groove is gradually narrowed from the opening toward the bottom.

The absorbent article according to any one of the above aspects, wherein the central portion is formed with a central lateral groove extending in the width direction of the absorbent core.

The absorbent article according to any one of the above aspects, wherein the side region is formed with a lateral longitudinal groove extending in the longitudinal direction of the absorbent core.

<7> The absorbent article according to the above <6>, wherein the side lateral region is formed with a lateral lateral groove extending in the width direction of the absorbent core.

The absorbent article of any one of the above-mentioned <3> to <7> wherein the one or both of the longitudinal grooves and the lateral grooves are made of the absorbent material for reducing the absorbent core. Formed by basis weight.

The absorbent article according to any one of the above aspects, wherein the central region and the lateral region of the absorbent core have a concave-convex shape on a non-skin opposite surface. On the other hand, the opposite side of the skin becomes flat.

The absorbent article according to any one of the above-mentioned <3>, wherein the central portion of the absorbent core has a basis weight smaller than a low basis weight portion forming a bottom portion of the longitudinal groove High high base.

<11> The absorbent article according to the above <10>, wherein the density of the absorbent member is higher than the low basis weight portion in the high basis weight portion of the central region.

The absorbent article according to any one of the above-mentioned <6>, wherein the side region of the absorbent core has a base portion lower than a base portion forming a bottom portion of the longitudinal groove. Higher weight than the base weight.

<13> The absorbent article according to the above <12>, wherein the high basis weight portion of the side region has a higher density of the absorbent member than the low basis weight portion.

The absorbent article according to any one of the above aspects, wherein the ratio of the width of the central protruding portion to the entire width of the absorbent core is 20% or more and 80% or less.

The absorbent article according to any one of the above aspects, wherein the ratio of the thickness of the central region to the thickness of the lateral region is 110% or more and 400% or less.

The absorbent article according to any one of the above-mentioned <10>, wherein the base of the low basis weight is at a base of the high basis weight in the central region of the absorbent core. The ratio of the weight is 5% or more and 80% or less.

The absorbent article of any one of the above-mentioned <7> to <16>, wherein the lateral groove of the central region and the lateral groove of the lateral region are at the boundary portion between the central region and the lateral region The positions of the absorbent cores in the longitudinal direction are the same.

<18> The absorbent article according to any one of <3> to <17> wherein the bottom of the longitudinal groove in the central region is located below the lower surface of the lateral region.

The absorbent article according to any one of the above aspects, wherein the bottom portion of the longitudinal groove in the central region is located at substantially the same position as the lower surface of the lateral region.

The absorbent article according to any one of the above-mentioned <3>, wherein the bottom of the longitudinal groove in the central region is located above the lower surface of the lateral region.

The absorbent article according to any one of the above aspects, wherein the ratio of the depth of the lateral groove in the central region to the entire thickness of the absorbent core of the central region is 50%. Above and below 95%.

The absorbent article according to any one of the above-mentioned items, wherein the central protruding portion protrudes from the lower surface of the opposing portion of the excretory portion from the lower surface of the lateral portion with respect to the entire thickness of the central portion. The ratio is 20% or more and 90% or less.

<23> The absorbent article according to the above <22>, wherein the central projection is rearward The ratio of the height of the square protruding from the surface below the side region to the entire thickness of the central region is 20% or more and 90% or less.

The absorbent article according to any one of the above aspects, wherein the absorbent article has a front portion, a drain portion facing portion, and a rear portion in a longitudinal direction thereof, and the drain portion is opposite to the drain portion The skin side sheet, the non-skin side sheet, and the absorbent core body have a pair of side flap portions on the left and right sides of the absorbent body in a region overlapping in a plan view.

The absorbent article according to any one of the above aspects, wherein the absorbent body of the rear portion has a pair of rear wing portions on the left and right sides of the absorbent body.

The absorbent article according to any one of the above-mentioned items, wherein the absorbent article is a menstrual sanitary napkin.

[Industrial availability]

The absorbent article of the present invention is excellent in the wearing feeling at the time of wearing, and is particularly excellent in the feeling of wearing when a high pressure is applied.

1‧‧‧Sanitary cotton

2a‧‧‧Front sheet

2b‧‧‧Side sheet

3‧‧‧Non-skin side sheet

4‧‧‧Acceptor

5‧‧‧ Central Highlights

12‧‧‧The protrusion is adjacent to the high-density part

41‧‧‧Central area

41'‧‧‧Central thick-walled area

42‧‧‧High base

42d‧‧‧ forming part of the central projection of the central area

42u‧‧‧ is closer to the skin side than the part of the central protrusion that forms the central area

43‧‧‧Low basis weight

44a‧‧‧ transverse slot

44b‧‧‧ transverse slot

44d‧‧‧ bottom

45‧‧‧Side area

45'‧‧‧Side area of the absorber

46‧‧‧High base

47‧‧‧Low basis weight

48‧‧‧Low basis weight

50‧‧‧ longitudinal slot

50a‧‧‧ openings

50b‧‧‧ bottom

52‧‧‧ side longitudinal groove

52a‧‧‧ Opening

52b‧‧‧ bottom

La‧‧‧Width length of the opening

Length of the width of the bottom of Lb‧‧‧

Surface under the S2‧‧‧ lateral area

t‧‧‧The protruding height of the central protrusion

T1‧‧‧ Thickness of the central area

Thickness of the lateral area of t2‧‧‧

W1‧‧‧Width of central projection

W2‧‧‧The entire width of the absorbent core

Y‧‧‧Width direction

Claims (26)

An absorbent article comprising an absorbent article having an absorbent body between a skin side sheet forming a skin facing surface and a non-skin side sheet forming a non-skin facing surface, wherein the absorbent body comprises an absorbent article The longitudinally elongated absorbent core having a long front-rear direction, the absorbent core having a side portion in the opposite portion of the drain portion, which is located on both sides in the width direction, and a central portion located further in the lateral region The center side of the width direction is larger than the side area; the side area is integrally formed with the center area, and the center area protrudes toward the non-skin side sheet side, and the side of the absorber in a plan view The region in which the region is located has a non-joining region that is not joined to the above-described non-skin side sheet. The absorbent article of claim 1, wherein the portion adjacent to the central region in the lateral region has a high density portion having a higher density than the central region. The absorbent article according to claim 1, wherein a longitudinal groove having a bottom portion on a side opposite to the longitudinal direction of the absorbent core and a bottom portion on the non-skin facing surface side of the central region is formed In the groove, the length of the bottom portion in the width direction is narrower than the opening portion. The absorbent article of claim 3, wherein the lengthwise direction of the longitudinal groove is gradually narrowed from the opening toward the bottom. The absorbent article according to claim 1, wherein a central lateral groove extending in a width direction of the absorbent core is formed in the central portion. The absorbent article according to claim 1, wherein a lateral longitudinal groove extending in a longitudinal direction of the absorbent core is formed in the lateral region. The absorbent article according to claim 6, wherein a side lateral groove extending in a width direction of the absorbent core is formed in the side region. The absorbent article of claim 3, wherein either or both of the longitudinal grooves and the lateral grooves are formed by reducing a basis weight of the absorbent material of the absorbent core. The absorbent article according to claim 3, wherein each of the central region and the lateral region of the absorbent core has a concave-convex shape on a non-skin opposing surface, and on the other hand, the opposite surface of the skin becomes flat . The absorbent article according to claim 3, wherein a central portion of the absorbent core has a high basis weight having a higher basis weight than a low basis weight portion forming a bottom portion of the longitudinal groove. The absorbent article of claim 10, wherein the density of the absorbent member is higher than the low basis weight portion in the high basis weight portion of the central region. The absorbent article according to claim 6, wherein the side region of the absorbent core has a high basis weight having a higher basis weight than a low basis weight portion forming a bottom portion of the longitudinal groove. The absorbent article of claim 12, wherein the high basis weight portion of the side region has a higher density of the absorbent member than the low basis weight portion. The absorbent article according to claim 1, wherein the ratio of the width of the central projection to the entire width of the absorbent core is 20% or more and 80% or less. The absorbent article of claim 1, wherein a ratio of a thickness of the central region to a thickness of the lateral region is 110% or more and 400% or less. The absorbent article according to claim 10, wherein a ratio of a basis weight of the low basis weight portion to a basis weight of the high basis weight portion in the central region of the absorbent core is 5% or more and 80% or less. The absorbent article of claim 7, wherein the absorption of the transverse groove of the central region and the lateral groove of the lateral region is at the boundary between the central region and the lateral region The positions of the cores in the longitudinal direction are the same. The absorbent article of claim 3, wherein the bottom of the longitudinal groove in the central region is located lower than the lower surface of the lateral region. The absorbent article of claim 3, wherein the bottom of the longitudinal groove in the central region is present at substantially the same position as the lower surface of the lateral region. The absorbent article of claim 3, wherein the bottom of the longitudinal groove in the central region is located above the lower surface of the lateral region. The absorbent article of claim 5, wherein a ratio of a depth of the lateral groove in the central region to an entire thickness of the absorbent core of the central region is 50% or more and 95% or less. The absorbent article according to claim 1, wherein the ratio of the height of the central projection to the lower surface of the opposing portion of the excretory portion from the lower surface of the lateral portion is 20% or more and 90% or less with respect to the entire thickness of the central portion. The absorbent article according to claim 22, wherein the ratio of the height of the central projection protruding from the lower surface of the rear portion to the lower surface of the lateral region relative to the entire thickness of the central region is 20% or more and 90% or less. The absorbent article according to claim 1, wherein the absorbent article has a front portion, an excretion portion facing portion, and a rear portion in a longitudinal direction thereof, and the skin side sheet and the non-skin side sheet in the opposing portion of the excretory portion The material and the absorbent core have a pair of side flap portions on the right and left sides of the absorbent body in a region overlapping in a plan view. The absorbent article of claim 1, wherein the pair of rear wing portions are provided on the left and right sides of the absorbent body in the rear portion. The absorbent article of claim 1, wherein the absorbent article is a menstrual napkin.