JP6578341B2 - Sanitary napkin - Google Patents

Description

  The present invention relates to an absorbent article such as a sanitary napkin.

  An absorbent article of a type that is used inside an undergarment, such as a sanitary napkin, is provided with an absorber for absorbing a liquid material such as menstrual blood. An absorber has a core wrap sheet, a surface sheet, etc. which coat | cover the said absorptive core other than an absorptive core long in the front-back direction. For example, Patent Literature 1 discloses an absorbent article in which a protruding portion for improving fit to the excretion region is provided in the central region of the absorbent core facing the excretion region of the wearer.

JP 2014-104093 A

  Absorbent articles such as sanitary napkins typically have a width that is wider than a person's crotch width. For this reason, when an external force is applied from the left and right outer sides to the inner side in the width direction at the time of wearing, a deformation that lowers the fit with the excretion region occurs in the central region of the absorbent core, and liquid leakage is likely to occur. For this reason, the technique which suppresses a deformation | transformation of the center area | region of the absorptive core with respect to external force is desired.

  The subject of this invention is related with the absorbent article which can suppress the deformation | transformation of the center area | region of an absorptive core.

An absorbent article according to an embodiment of the present invention includes an absorbent core and a core wrap sheet.
The said absorptive core is the said front core part and back core part which were formed in the said longitudinal direction intermediate part between the front core part and back core part which are located in the both ends part of a longitudinal direction between a pair of constricted area | regions. It has a narrower intermediate core part. The intermediate core portion includes a high basis weight portion formed at the center in the width direction, and a pair of low basis weight portions having a basis weight lower than the high basis weight portion and formed around the high basis weight portion. Including.
The core wrap sheet has a core covering portion that covers the absorbent core and a pair of constricted covering portions that cover the pair of constricted regions.

  As described above, according to the absorbent article of the present invention, deformation of the central region of the absorbent core can be suppressed. Thereby, generation | occurrence | production of the liquid leak by a deformation | transformation of an absorptive core can be prevented.

It is a perspective view showing an absorptive article concerning one embodiment of the present invention. It is a top view of the absorptive article. It is sectional drawing cut | disconnected by the III-III line of FIG. It is a top view which shows the absorptive core of the said absorbent article. It is sectional drawing which shows the absorber of the said absorbent article typically. It is a schematic cross section of the absorber. It is a principal part top view explaining the constriction coating | coated part in the said absorber. It is sectional drawing which shows the other structural example of the said absorber typically. It is sectional drawing which shows the other structural example of the said absorber typically. It is a top view which shows typically the other structural example of the high basic weight part in the said absorptive core. It is a top view which shows typically the other structural example of the high basic weight part in the said absorptive core typically. It is a top view which shows typically the other structural example of the front-end | tip shape of the said high basic weight part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the drawing, an X axis, a Y axis, and a Z axis that are orthogonal to each other are shown.

[Overall structure of napkin]
FIG. 1 is a perspective view showing an absorbent article 1 according to an embodiment of the present invention. In FIG. 1, the X-axis direction corresponds to the front-rear direction, the Y-axis direction corresponds to the left-right direction, and the Z-axis direction corresponds to the up-down direction.
FIG. 2 is a plan view (or a developed view) of the absorbent article 1 and shows a state in which the absorbent article 1 shown in FIG. 1 is extended along the XY plane. In the absorbent article 1 shown in FIG. 2, the X-axis direction corresponds to the longitudinal direction, the Y-axis direction corresponds to the width direction, and the Z-axis direction corresponds to the thickness direction. Hereinafter, the absorbent article 1 is demonstrated in the aspect shown in FIG.

The absorbent article 1 of this embodiment is configured as a sanitary napkin, and is hereinafter referred to as a napkin 1.
The napkin 1 may be used at the time of sleeping, for example, may have a length of 30 cm or more along the longitudinal direction.

  In this embodiment, the napkin 1 includes a main body M, a pair of wing portions W, a pair of side guards G, and a pair of rear flap portions F.

The main body M has a front region M1, an intermediate region M2, and a rear region M3, which are divided along the longitudinal direction.
The front region M1 is a region disposed in front of the middle region M2 (the abdomen side of the wearer), and is configured to face the front side (abdomen) of the excretion region of the wearer when worn.
The intermediate area M2 is configured to face the excretion area when worn. In the case of a napkin having a wing portion, the region in the longitudinal direction X that overlaps the entire length of the wing portion is the intermediate region M2. In the case of a napkin that does not have a wing portion, the middle region when the entire length of the napkin is divided into three is defined as an intermediate region M2. Note that the intermediate region M2 may be positioned closer to the front of the main body M as illustrated, or may be positioned in the center of the main body M.
The rear region M3 is a region disposed on the rear side (back side of the wearer) of the intermediate region M2, and is configured to face the rear side (buttock) of the excretion region when worn.

The wing portion W is configured to protrude greatly from the intermediate region M2 to the outside in the width direction.
The side guard G is disposed so as to extend in the longitudinal direction at the peripheral edge in the width direction of the main body M including the intermediate region M2. The side guard G stands up in the thickness direction during mounting and prevents leakage of liquid in the width direction.
The rear flap portion F is configured to bulge outward from the rear region M3 in the width direction.
The napkin 1 may not have at least one of the wing part W, the side guard G, and the rear flap part F.

[Configuration of each part of the napkin]
3 is a cross-sectional view taken along line III-III in FIG.
The napkin 1 includes an absorbent body 11, a top sheet 12, a back sheet 13, a pair of side sheets 14, an adhesive portion 15, and a pressing groove 16. In the main body M, the napkin 1 has a configuration in which a back sheet 13, an absorbent body 11, and a top sheet 12 are laminated.

  The absorbent body 11 has a longitudinal direction in the X-axis direction, and is disposed at the center in the thickness direction of the napkin 1. The absorbent body 11 absorbs a liquid material (hereinafter, also referred to as “liquid”) such as menstrual blood of the wearer from the surface on the surface sheet 12 side, and diffuses inside to hold the liquid.

The absorbent body 11 has an absorbent core 20 and a core wrap sheet 30.
The absorbent core 20 has a function of absorbing and holding the liquid. The absorbent core 20 may be formed of, for example, a fiber assembly made of hydrophilic fibers such as pulp fibers, or may have a configuration in which a water absorbent polymer is held in the fiber assembly. .
The core wrap sheet 30 covers the absorbent core 20 and has, for example, a function of maintaining the shape of the absorbent core 20. The core wrap sheet 30 is formed of, for example, thin and soft paper such as tissue paper, liquid permeable nonwoven fabric, or the like.
The details of the absorber 11 will be described later.

  The top sheet 12 is configured as a liquid-permeable sheet material and is disposed on the absorber 11. The top sheet 12 forms an outer surface of the main body M that is above the napkin 1 in the thickness direction.

  The back sheet 13 is disposed to face the top sheet 12 in the thickness direction with the absorber 11 interposed therebetween. The back sheet 13 forms an outer surface below the napkin 1 in the thickness direction. The back sheet 13 is joined to the top sheet 12 and the side sheet 14 by an adhesive, a heat seal, etc., for example in a peripheral part.

The pair of side sheets 14 are opposed to each other in the width direction with the top sheet 12 interposed therebetween, and are disposed on the periphery in the width direction of the napkin 1. The side seat 14 constitutes a side guard G. The side guard G has a side guard component 141 and a surface sheet joint 142.
The side guard component 141 is disposed on the peripheral edge of the main body M in the width direction. The side guard constituting portion 141 includes an elastic member 141a such as a thread-like elastic member disposed along the longitudinal direction between the folded portion of the side sheet 14 folded outward in the width direction and the surface sheet joining portion 142. Therefore, it is configured to be able to stand on the skin side.
The top sheet joining portion 142 is disposed in a region facing the circumferential edge of the top sheet 12 and joins the side sheet 14 and the top sheet 12 in the thickness direction (Z-axis direction).

  The adhesive portion 15 is a configuration for fixing the napkin 1 to the underwear, and is formed on the outer surface of the back sheet 13. The adhesion part 15 has the main body adhesion part 151 provided in the main body M, the wing adhesion part 152 provided in the wing part W, and the back flap adhesion part (not shown) provided in the back flap part F, for example.

  The pressing groove 16 is configured as a linear groove formed by pressing the absorber 11 (the absorbent core 20 and the core wrap sheet 30) and the topsheet 12. The pressing groove 16 is configured to circulate around the main body M as shown in FIGS. The compressed groove 16 can induce deformation into a shape that fits the wearer when worn, and can enhance the effect of preventing leakage of the napkin 1 outward in the width direction and the longitudinal direction.

  Next, the detail of each part is demonstrated.

(Basic structure of absorber)
The absorbent body 11 has the absorbent core 20 and the core wrap sheet 30 as described above.

FIG. 4 is a plan view showing the surface 20 </ b> A of the absorbent core 20.
The absorptive core 20 has the front core part 21 located in the front area | region M1, the intermediate | middle core part 22 located in the intermediate | middle area | region M2, and the back core part 23 located in the back area | region M3. The front core portion 21 and the rear core portion 23 are located on both ends in the longitudinal direction of the absorbent core 20, and the intermediate core portion 22 is located between the front core portion 21 and the rear core portion 23. The intermediate core portion 22 extends from the rear side of the front region M1 to the front side of the rear region M3 via the intermediate region M2. The absorptive core 20 has a plane shape that is symmetrical in the width direction.

  FIG. 4 shows widths D1, D2, and D3, which are dimensions in the width direction 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 smaller than both the width D1 of the front core portion 21 and the width D3 of the rear core portion 23. That is, the absorptive core 20 has the intermediate core part 22 narrower than the front core part 21 and the rear core part 23 formed between the pair of constricted regions 22 s in the intermediate part in the longitudinal direction.

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

In the case of a sanitary napkin, the widths D1 and D3 of the front core portion 21 and the rear core portion 23 are, for example, 60 mm or more and 100 mm or less, and preferably 70 mm or more and 90 mm or less.
The thicknesses of the front core portion 21 and the rear core portion 23 are preferably 2 mm or more and 10 mm or less, more preferably 2.5 mm or more and 9 mm or less. The basis weights of the front core portion 21 and the rear core portion 23 are preferably 90 g / m ² or more and 500 g / m ² or less, more preferably 100 g / m ² or more and 450 g / m ² or less.
In addition, when an absorptive core has a groove | channel like this embodiment, the thickness and basic weight of each core part mean the thickness and basic weight in the part (namely, block part) except a groove part. . Hereinafter, when there is no notice in particular, prescription | regulation of the thickness and basic weight in an absorptive core is the same as the above-mentioned.

  The width D2 of the intermediate core portion 22 is typically formed to be larger than a general wearer's crotch width (about 30 mm), and is, for example, 40 mm or more and 75 mm or less, and preferably 50 mm or more and 70 mm or less. This makes it less susceptible to external forces applied inward in the width direction added by the wearer's legs, etc., and can also handle mounting position shifts in the width direction, giving the wearer a sense of security. it can. In addition, it is preferable that the width | variety in the longitudinal direction full length of the intermediate core part 22 is in the range mentioned above except taper part 22a, 22b.

  The length in the longitudinal direction of the intermediate core portion 22 is, for example, 60 mm or more and 180 mm or less, preferably 80 mm or more and 170 mm or less. Thereby, even when there is a displacement in the longitudinal direction, the intermediate core portion 22 can be opposed to the wearer's excretion region.

  As shown in FIG. 4, the intermediate core portion 22 has tapered portions 22 a and 22 b at the front end and the rear end of both edges thereof. The taper portions 22 a and 22 b increase the width of the intermediate core portion 22 toward the front core portion 21 and the rear core portion 23. The constricted region 22s corresponds to a space formed between both edge portions of the intermediate core portion 22 and the tapered portions 22a and 22b.

  The intermediate core portion 22 includes a high basis weight portion 24 and a low basis weight portion 25 having a lower basis weight than the high basis weight portion 24. In FIG. 4, the high basis weight portion 24 is indicated by a dense dot pattern, and the low basis weight portion 25 is indicated by a coarse dot pattern.

The high basis weight portion 24 is formed at the center in the width direction of the intermediate core portion 22. The high basis weight portion 24 is disposed so as to face the excretion region of the wearer when the napkin 1 is worn. The low basis weight portion 25 is formed around the high basis weight portion 24. Here, the “periphery” means at least a region including the outside in the width direction of the high basis weight portion 24. Moreover, it is preferable that the low basic weight part 25 exists in the intermediate area M2 of the napkin 1 at least.
The high basis weight part 24 has a longitudinal shape in the front-rear direction, and its maximum width is, for example, 15 mm or more and 60 mm or less, and preferably 20 mm or more and 50 mm or less. By making the said width | variety into such a range, the fit property to a wearer's excretion area | region can be improved and sufficient absorption amount can be ensured.
The high basis weight portion 24 is formed thicker than the low basis weight portion 25 (see FIG. 3), and protrudes upward in the thickness direction (on the topsheet 12 side). Thereby, the favorable fitting property between the center area | region of the intermediate area M2 of the napkin 1 corresponding to the high basic weight part 24 and a wearer's excretion area | region is ensured.

The basis weight of the high basis weight portion 24 is, for example, 400 g / m ² or more and 1000 g / m ² or less, and preferably 500 g / m ² or more and 900 g / m ² or less.
The basis weight of the low basis weight portion 25 is, for example, 100 g / m ² or more and 700 g / m ² or less, and preferably 200 g / m ² or more and 600 g / m ² or less.

The thickness of the high basic weight part 24 and the low basic weight part 25 can be set in consideration of the basic weight.
The thickness of the high basis weight portion 24 in the Z-axis direction is, for example, 3 mm or more and 15 mm or less, and preferably 5 mm or more and 13 mm or less.
The thickness in the Z-axis direction of the low basis weight portion 25 is, for example, 2 mm or more and 12 mm or less, preferably 3 mm or more and 10 mm or less.

  As a measuring method of the basic weight of an absorptive core, the measurement object area | region of the absorptive core 20 is cut | disconnected using the single blade razor by a feather company, and a small piece is obtained so that it may become a predetermined area. The weights of these pieces are measured using an electronic balance (Electronic balance GR-300 manufactured by A & D, accuracy: 4 digits after the decimal point). The basis weight of the small piece is calculated by dividing the obtained weight by the area of the small piece of each part. About each of each part, let the average of the basic weight of five small pieces be a basic weight.

  The measurement of the thickness of the absorber 11 which is a measurement target is performed by measuring the thickness of a small piece cut out in order to measure the basis weight of each part. A measurement part of a small piece cut out from the absorbent article is pressurized at a pressure of 5 kPa for 10 minutes, and measurement is performed immediately after dewetting. An acrylic plate having a size of 20 mm × 20 mm and a thickness of 3 mm is placed on the absorber 3 in the central area of the sample after dewetting, and a non-contact type laser displacement meter (laser head LK-G30, displacement meter LK- manufactured by KEYENCE). Measure the thickness of the sample using the GD 500. If the size of the cut piece is small and difficult to measure with a non-contact type laser displacement meter, the cross section of the cut sample is, for example, a microscope (Keyence Corporation). It may be observed and measured at a magnification of 20 to 100 times using VHX-1000).

The surface 20A of the absorbent core 20 is formed of a three-dimensional structural surface that faces the top sheet 12 and further includes a peripheral groove portion 26, a vertical groove portion 27, a horizontal groove portion 28, and the like. The back surface 20B of the absorbent core 20 faces the back sheet 13 and is typically formed as a flat surface.
The details of the peripheral groove portion 26, the vertical groove portion 27, and the horizontal groove portion 28 will be described later.

  FIG. 5 is a schematic plan view of the absorbent body 11 in a single state. 6 is a schematic diagram of the absorbent body 11 conceptually showing the relationship between the absorbent core 20 and the core wrap sheet 30, and corresponds to a cross-sectional view taken along the line VI-VI in FIG. FIG. 7 is a main part plan view for explaining the constricted covering portion 34 in the absorbent body 11. In FIG. 6, illustration of a longitudinal groove portion and the like formed on the surface 20 </ b> A of the absorbent core 20 is omitted.

  The core wrap sheet 30 is wound in the width direction of the absorbent core 20 so as to cover the front and back of the absorbent core 20. The length along the X-axis direction of the core wrap sheet 30 is formed to be equal to the length (full length) of the absorbent core 20 in the front-rear direction, but is not limited thereto, and is longer than the full length of the absorbent core 20. It may be short or short.

As the core wrap sheet 30, paper, non-woven fabric, or the like can be used as described above.
The core wrap sheet 30 may be composed of a single sheet material or a plurality of sheet materials. The core wrap sheet 30 may be joined to the top sheet 12 and the back sheet 13 by, for example, an adhesive applied in a predetermined pattern.

As shown in FIGS. 6 and 7, the core wrap sheet 30 has a pair of core covering portions (31 to 33) that cover each portion of the absorbent core 20 and a pair of constricted regions 22 s that cover the absorbent core 20. And a constricted covering portion 34.
The core covering portion includes a front core covering portion 31 that covers the front core portion 21, an intermediate core covering portion 32 that covers the intermediate core portion 22, and a rear core covering portion 33 that covers the rear core portion 23. In FIG. 5, the boundary between each of the core covering portions 31 to 33 and the constricted covering portion 34 is indicated by a one-dot chain line.

  Since the core wrap sheet 30 is made of a sheet material whose rigidity is sufficiently lower than that of the absorbent core 20, the core wrap sheet 30 covers the absorbent core 20 in a shape corresponding to the shape of the absorbent core 20. For example, the intermediate core covering portion 32 is deformed into a shape corresponding to the shape of the raised portion (high basis weight portion 24) of the surface 20A of the intermediate core portion 22, as shown in FIG.

  On the other hand, the constriction covering portion 34 extends between the outer edge portion of the intermediate core portion 22 and the constricted region 22 s by being bridged between the front core portion 21 and the rear core portion 23. For this reason, the constriction coating | cover part 34 is maintained in the shape corresponding to the constriction area | region 22s in the state to which the fixed tension | tensile_strength was provided in the front-back direction.

  Although the core material which comprises the absorptive core 20 does not exist in the inside of the constriction coating | cover part 34 as shown in FIG. 6, it isolate | separates from the fiber which protruded outward from the periphery of the absorptive core 20, and the absorptive core 20 A part of the core material may exist partially. In FIG. 6, the constricted covering portion 34 is drawn to have a thickness equivalent to that of the low basis weight portion 25 of the absorbent core in the thickness direction Z. However, in the absorbent article, as shown in FIG. 3. Furthermore, there is almost no space in the thickness direction, and the front surface region 341 and the back surface region 342 are preferably in contact with each other.

(Typical action of absorber)
In the absorbent body 11 having the above-described configuration, the high basis weight portion 24 has higher rigidity than the low basis weight portion 25, and the low basis weight portion 25 has higher rigidity than the constricted covering portion 34. For this reason, the intermediate region M2 of the absorbent body 11 to which the intermediate core portion 22 belongs is divided into a plurality of regions whose rigidity decreases stepwise from the center in the width direction toward the outside. Accordingly, even when an external force is applied from the left and right outer sides, the external force is sufficiently relaxed in the constricted covering portion 34 and the low basis weight portion 25 adjacent thereto, and it is difficult to propagate to the high basis weight portion 24. It becomes possible to effectively suppress deformation in the amount portion 24.

  For example, the intermediate region M2 of the napkin 1 receives an external force that is always directed inward in the width direction from both legs of the wearer on the outer side in the width direction when the wearer is walking, running, or sleeping. As described above, the absorber 11 is configured such that the rigidity gradually decreases from the center in the width direction toward the outside. For this reason, when an external force is received from the left and right sides, typically, the pair of constricted covering portions 34 is deformed first, and then the low basis weight portion 25 is further deformed. Thereby, the external force which acts on the absorber 11 is absorbed or relieved in steps.

  In particular, when the pair of constricted covering portions 34 receives an external force from both the left and right sides, it generates a predetermined tensile force in the front-rear direction, which acts as a resistance against the external force (compression deformation resistance in the width direction). As a result, the buffering effect on the external force is increased, and the deformation of the low basis weight portion 25 is further suppressed. Therefore, the external force transmitted to the high basis weight portion 24 is reduced, and therefore the deformation of the high basis weight portion 24 is effectively suppressed. . Thereby, since the stable fitting property of the middle region M2 with respect to the wearer's excretion region is maintained, occurrence of liquid leakage due to deformation of the napkin 1 is prevented.

  In particular, when the wing W is provided like the napkin 1, the wing is folded and bonded to the crotch portion of the shorts, and therefore, the followability of the napkin 1 tends to increase with respect to the movement in the wearer's crotch portion. . In such a case, it is very useful to have the intermediate core portion 22 so as to overlap the wing W in the longitudinal direction.

  The magnitude of the drag of the constricted covering portion 34 against the external force is the rigidity of the front core portion 21 and the rear core portion 23, the length of the outer edge line L1 (see FIG. 5) of the constricted covering portion 34, and the outer edge line L1 in the constricted region 22s. It can be set as appropriate according to the position, the rigidity of the core wrap sheet 30, and the like.

(Cinched coating)
The outer edge line L <b> 1 of the constricted covering portion 34 corresponds to the edge portion of the core wrap sheet 30. Therefore, for example, as shown in FIG. 7, the outer edge line L1 of each of the pair of constricted covering portions 34 is an imaginary line connecting the outer edge portions P1, P2 of the front core portion 21 and the rear core portion 23 in each of the pair of constricted regions 22s. A bisector L4 of a line segment parallel to the width direction connecting L2 and the outer edge line L3 corresponding to the outer edge of the intermediate core portion 22 (the outer edge line L2 passing through the midpoint M of the line segment parallel to the width direction) , A line parallel to L3), and is located outside in the width direction.
Thereby, since the sufficient width | variety which can allow the deformation | transformation of the constriction coating | cover part 34 is ensured, the constriction coating | coated part using the rigidity of the front core part 21 and the back core part 23 which are located in the back and front The buffer effect of the external force by the compression deformation resistance to the width direction of 34 increases, and the deformation | transformation inhibitory effect of the high basic weight part 24 can be heightened.

  In order to make the above-described effect more reliable, the core wrap sheet 30 is preferably non-extensible or hardly extensible. Here, non-extensible or difficult stretch means that the elongation when a tensile load is applied to the sheet is low. Specifically, the elongation when a 1N load is applied to a 50 mm width sheet is 25%. The following is preferable.

  The outer edge portions P1 and P2 of the front core portion 21 and the rear core portion 23 are constricted starting points of the absorbent core 20 that are the base points of the constricted region 22s, for example, the front core portion 21, the rear core portion 23, and the intermediate core portion 22. This corresponds to the boundary between the tapered portions 22a and 22b. The tapered portions 22a and 22b are not limited to a linear shape, and may have a curved shape that is convex toward the constricted region 22s. The tapered portions 22a and 22b may be omitted. In this case, the intermediate core part 22 is connected to the front core part 21 and the rear core part 23 via a step part perpendicular to the front-rear direction.

The outer edge line L1 of the constricted covering portion 34 is not limited to the case of extending linearly at the outer edge portions P1 and P2, and a partially bent (or curved) region may be formed in the constricted start region.
The outer edge line L1 of the constricted covering portion 34 can be adjusted by, for example, the magnitude of tension in the width direction (Y-axis direction) of the core wrap sheet 30 when the core wrap sheet 30 is wound around the absorbent core 20.

On the other hand, the buffering effect of the external force by the constricted covering portion 34 can be enhanced by the form of the core wrap sheet 30 that forms the constricted covering portion 34.
For example, as shown in FIG. 8, the pair of constricted covering portions 34 includes a front side region 341 and a back side region 342 that sandwich the constricted region 22 s from the thickness direction. In the present embodiment, the pair of constricted covering portions 34 face each other without being bonded to each other in the thickness direction of the absorbent core 20. In other words, the front side region 341 and the back side region 342 are opposed to each other in the thickness direction without bonding their inner surfaces by means such as bonding with a bonding material or thermocompression bonding.
As a result, the rigidity of the constriction covering portion 34 is made uniform, and the front side region 341 and the back side region 342 can be freely deformed without being constrained to each other, so that the entire constriction covering portion 34 is flexibly deformed. Thus, the buffering effect against external force can be enhanced.

Furthermore, in this embodiment, the front side area | region 341 and the back side area | region 342 are mutually formed continuously in the peripheral part (outer edge) of the width direction of a pair of constriction coating | covering part 34. FIG. That is, the front side region 341 and the back side region 342 are formed of a common sheet material folded back in the constricted region 22.
Thereby, since the rigidity of the whole constriction coating | coated part 34 increases, the buffer effect with respect to an external force is heightened.

(Low basis weight part)
In order to further enhance the external force buffering effect of the low basis weight portion 25, the low basis weight portion 25 may be provided with a plurality of regions having different densities. FIG. 8 is a schematic cross-sectional view of the absorbent body 11A having the low basis weight portion 25 having such a structure.

As shown in FIG. 8, in the absorbent core 20, the low basis weight portion 25 includes a side end portion 251 and a high density portion 252. The side end portion 251 is located outward of the high basis weight portion 24 in the width direction. The high density portion 252 has a higher density than the side end portion 251 and is located between the side end portion 251 and the high basis weight portion 24. Since the high density portion 252 has a lower basis weight than the high basis weight portion 24, the intermediate core portion 22 has higher rigidity in the order of the side end portion 251, the high density portion 252 and the high basis weight portion 24.
Thus, by gradually increasing the rigidity of the low basis weight portion 25 from the side end portion 251 toward the high basis weight portion 24, the low basis weight portion 25 can be reliably deformed from a region farther from the high basis weight portion 24. That is, it is possible to avoid the entire area of the low basis weight portion 25 from being deformed simultaneously when receiving an external force. Thereby, the deformation preventing effect of the high basis weight portion 24 can be further enhanced.

  The method of providing the high-density portion 252 in the low basis weight portion 25 is not particularly limited. For example, the basis weight is made larger than the side end portion 251 or the region between the side end portion 251 and the high basis weight portion 24 is formed. The high density portion 252 can be formed by compressing in the thickness direction. The high density part 252 does not need to be provided adjacent to the high basis weight part 24, and a region having a lower density than the high density part 252 may be interposed therebetween.

Further, the absorbent core 20 can be provided with the compressed groove 16 integrally with the top sheet 12 and the core wrap sheet 30 so as to overlap the high density portion 252 in plan view. FIG. 9 shows a cross-sectional view of the absorbent body in which the compressed grooves 16 are provided in the high density portion. In the absorbent body of FIG. 9, the low basis weight portion 25 includes a side end portion 251, and a first high density portion 253 and a second high density portion 254 that are higher in density than the side end portion 251. The first high density portion 253 is formed between the side end portion 251 and the high basis weight portion 24. The second high density portion 254 is formed between the first high density portion 253 and the high basis weight portion 24. In the form of FIG. 9, the first high density portion 253 has a higher density than the second high density portion 254. Further, the thickness is smaller than that of the side end portion 251 and the second high density portion 254.
In addition, the 1st high density part 253 may be provided in the position corresponding to the formation position of the pressing groove 16 on the main body M (refer FIG. 3). Thereby, the high density part 253 can be formed in the low basic weight part 25 simultaneously with formation of the pressing groove 16.

(Shape of high basis weight part)
Since the intermediate core portion 22 constitutes the intermediate region M2 of the napkin 1 that faces the excretion region of the wearer, the external force directed inward in the width direction is the largest. Therefore, in the present embodiment, the high basis weight portion 24 is formed at least over the entire length of the intermediate core portion 22 (see FIG. 4).
Thereby, when the napkin 1 is attached, a good fit between the high basis weight portion 24 and the excretion region can be ensured.
Moreover, since the state where the low basic weight area | region (low basic weight part 25) whose basic weight is lower than the high basic weight part 24 exists over the whole width direction of the intermediate core part 22 is avoided, all area | regions of the intermediate core part 22 The deformation suppression effect of the high basis weight part 24 based on the rigidity difference in the width direction as described above can be ensured.

  As shown in FIGS. 10A and 10B, the total length of the high basis weight portion 24 may be larger than the total length of the intermediate core portion 22. Thereby, the rigidity difference of the width direction over the whole area | region of the intermediate core part 22 is securable stably. Moreover, even if the position shift of the front-back direction between the intermediate | middle area | region M2 and an excretion area | region arises at the time of mounting | wearing of the napkin 1, the favorable fitting feeling between the high basic weight part 24 and an excretion area | region can be ensured. .

Here, in the example of FIGS. 10A and 10B, the front end portion 241 and the rear end portion 242 of the high basis weight portion 24 are extended to the front core portion 21 and the rear core portion 23, respectively. Only one of the rear end 242 and the rear end 242 may be extended to the front core portion 21 or the rear core portion 23.
On the other hand, the overall length of the low basis weight portion 25 may be the same as the overall length of the intermediate core portion 22 as shown in FIG. 10A, or expanded to match the overall length of the high basis weight portion 24 as shown in FIG. 10B. May be.

  Moreover, as shown to FIG. 11A and B, the high basic weight part 24 may be formed in the front core part 21 side or the back core part 22 side as a whole. Since the high basis weight portion 24 has a total length equal to or greater than the total length of the intermediate core portion 22, it is possible to ensure a good fit between the high basis weight portion 24 and the excretion region when the napkin 1 is attached. .

  10 and 11, when the high basis weight portion 24 extends from the intermediate core portion 22 to at least one of the front core portion 21 and the rear core portion 23, the length of the extended portion is extended. In the front core portion 21, the length in the direction is 30% or less of the length of the front core portion 21, and further 20% or less. In the rear core portion 23, the length of the rear core portion 23 is 20% or less, further 10% or less is preferable for obtaining a good wearing feeling and fit.

Furthermore, in this embodiment, the longitudinal direction edge part (front-end part 241 and rear-end part 242) of the high basic weight part 24 has a shape where a width | variety reduces gradually toward a front-end | tip (refer FIG. 4).
As a result of the front end portion 241 and the rear end portion 242 approaching the front core portion 21 and the rear core portion 23, these end portions 241 and 242 are easily subjected to external force not only in the width direction but also in the longitudinal direction or the direction intersecting therewith. Even if it becomes, the external force can be effectively released by making the tip tapered. Thereby, it is possible to prevent the deformation of the high basis weight portion 24.

The front end 241 and the rear end 242 are typically semicircular (see FIG. 4), but as schematically shown in FIGS. There is no particular limitation as long as it is a shape that can disperse an external force acting in a plane, such as a combination shape with a straight line.
As an effect of preventing deformation of the high basis weight portion 24, for example, the front end portion 241 and the rear end portion 242 are more preferably semicircular (FIG. 4) or triangular (FIG. 12A).

(Relationship between the rigidity of the intermediate core part and the rigidity of the front and rear core parts)
The absorbent core 20 has the front core part 21, the intermediate core part 22, and the rear core part 23 as mentioned above. The basis weights of the front core part 21 and the rear core part 23 are not particularly limited, but in this embodiment, the front core part 21 and the rear core part 23 have a lower basis weight than the low basis weight part 25.
Thereby, since the rigidity of the intermediate core part 22 is higher than that of the front core part 21 and the rear core part 23, it is less affected by deformation of the front core part 21 and the rear core part 23. And stable posture.

  Further, since the front core portion 21 and the rear core portion 23 are less rigid and more easily deformed than the intermediate core portion 22, external forces applied to the napkin 1 from the front and rear directions are buffered at the front core portion 21 and the rear core portion 23. And the deformation | transformation of the intermediate | middle area | region M2 (intermediate core part 22) facing an excretion area | region can be suppressed.

  In particular, in the napkin 1 of the present embodiment in which the rear core portion 23 is configured with a relatively large area, the behavior of the rear core portion 23 has a great influence on the posture of the intermediate core portion 22. For this reason, it is very advantageous to configure the intermediate core portion 22 with higher rigidity than the rear core portion 23 in order to ensure a stable mounting property of the intermediate core portion 22 when sleeping.

10 and 11, in the case where the high basis weight portion 24 extends to the front core portion 21 or the rear core portion 23, the basis weight of the low basis weight portion 25 and the front core portion 21 or the rear side. The basis weight of the 2 part 42 is compared as follows.
In the case where the high basis weight portion 24 extends to the front core portion 21, the basis weight of the region in front of the front end portion 241 is set as the basis weight of the front core portion 21 with the front end portion 241 of the high basis weight portion 24 as a boundary. This basis weight is compared with the basis weight of the low basis weight portion 25. Similarly, in the case where the high basis weight portion 24 extends to the rear core portion 23, the basis weight of the region behind the rear end portion 242 is set to the rear core with the rear end portion 242 of the high basis weight portion 24 as a boundary. The basis weight of the portion 23 is defined, and this basis weight is compared with the basis weight of the low basis weight portion 25.

(Rim groove)
The intermediate core portion 22 is provided with the peripheral groove portion 26, the vertical groove portion 27, and the horizontal groove portion 28 as described above.

The peripheral groove portion 26 is formed between the high basis weight portion 24 and the low basis weight portion 25 so as to surround at least the periphery in the longitudinal direction of the high basis weight portion 24 (see FIG. 4).
In the present embodiment, the peripheral groove portion 26 is formed along the outer edge of the high basis weight portion 24. The peripheral groove portion 26 is formed with a basis weight lower than that of the low basis weight portion 25. Thereby, since the deformation around the high basis weight portion 24 is absorbed by the peripheral groove portion 26, the deformation of the low basis weight portion 25 is not easily transmitted to the high basis weight portion 24, and thus the high basis weight portion 24 is deformed around. Therefore, it is possible to ensure the deformation suppressing effect.

The longitudinal groove portions 27 extend along the longitudinal direction of the absorbent core 20 and are arranged at intervals along the width direction (see FIG. 4). The longitudinal groove portion 27 is formed on each of the front core portion 21, the intermediate core portion 22, and the rear core portion 23 over substantially the entire length in the longitudinal direction. With respect to the intermediate core portion 22, the longitudinal groove portion 27 is formed so as to pass through the center of the high basis weight portion 24.
The lateral grooves 28 extend along the width direction of the absorbent core 20 and are arranged at intervals along the longitudinal direction (see FIG. 4). The lateral groove portion 28 is formed in each of the front core portion 21, the intermediate core portion 22, and the rear core portion 23 over the entire length in the width direction.
By providing the vertical groove portion 27 and the horizontal groove portion 28 that are easily deformed with a low basis weight, the flexibility of the absorbent core 20 can be increased and the wearability can be improved. Further, the liquid absorption rate of the absorbent core 20 can be increased by drawing the liquid into the vertical groove portion 27 and the horizontal groove portion 28.

Similar to the peripheral groove portion 26, the lateral groove portion 28 provided in the intermediate core portion 22 can have a function of suppressing the propagation of external force. That is, the low basic weight portion 25 is partitioned into a plurality of blocks in the lateral groove portion 28 and the peripheral groove portion 26, and a certain effect of confining the deformation region in units of blocks is obtained. Thereby, the deformation preventing effect of the high basis weight portion 24 can be further enhanced.
The vertical groove portion 27 and the horizontal groove portion 28 are formed with the same width and depth, respectively, but of course not limited thereto. For example, the heights of the bottom portions of the longitudinal groove portion 27 and the lateral groove portion 28 with the back surface 20B of the absorbent core 20 as the reference surface are set to be the same as the height of the bottom portion of the peripheral groove portion 26 from the reference surface, for example (FIG. 3).

  The width of the peripheral groove part 26, the vertical groove part 27, and the horizontal groove part 28 is preferably 0.5 mm or more and 10 mm or less, and more preferably 1 mm or more and 5 mm or less. The depth of the peripheral groove part 26 is 0.5 mm or more and 10 mm or less, for example, and the depth of the vertical groove part 27 and the horizontal groove part 28 is 0.5 mm or more and 10 mm or less, for example.

  In the intermediate core portion 22, the vertical groove portion 27 may be wider than the peripheral groove portion 26. In this case, the absorbent core is easily deformed along the excretory part during wearing, and the excreted body fluid is easily diffused along the longitudinal direction. The vertical groove portion 27 is preferably larger than the peripheral groove portion 26 by 0.5 mm or more and 5 mm or less, and more preferably 1 mm or more and 3 mm or less.

(Main body adhesive part)
In order to prevent the deformation of the high basis weight portion 24 more effectively, the main body adhesive portion 151 provided on the main body M of the napkin 1 has a width equal to or smaller than the width of the intermediate core portion 22 as shown in FIG. In addition, it is preferably formed at a position facing the absorbent core 20 in the thickness direction across the back sheet 13.
In this way, by preventing the main body adhesive portion 151 from being coated directly under the constricted covering portion 34, the constricted covering portion 34 can be arbitrarily set during the application of an external force regardless of the type of underwear (the rigidity of the cloth of the underwear). The shape can be deformed, and as a result, the desired three-stage rigidity difference effect can be reliably exhibited in the width direction of the intermediate core portion 22.

The coating form of the main body adhesive portion 151 is not particularly limited, and may be configured by a single coating film or may be configured by a plurality of rows of coating films parallel to the longitudinal direction. The pressure-sensitive adhesive layer constituting the pressure-sensitive adhesive portion 15 can be formed of, for example, a hot melt pressure-sensitive adhesive. Examples of the hot melt pressure-sensitive adhesive that can be used for forming the pressure-sensitive adhesive layer include rubber-based, olefin-based, ethylene vinyl acetate (EVA) -based, and the like. In each pressure-sensitive adhesive layer, the hot-melt pressure-sensitive adhesive may be applied continuously or intermittently.
The main body adhesive portion 151 is covered with a release sheet (not shown) when the napkin 1 is not used. The said peeling sheet is affixed so that peeling is possible with respect to each adhesion part, and is peeled when the napkin 1 is used.

  The embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

  For example, although the example of the sanitary napkin was shown as an absorbent article in the above embodiment, it is not limited to this. The absorbent article of the present invention may be, for example, an incontinence pad or a cage sheet.

Furthermore, a high basic weight part is not limited to the structure which a width | variety reduces gradually in an edge part, The whole may be comprised by the substantially same width | variety.
Or the front side area | region and back side area | region of a constriction coating | coated part may be mutually joined, and may be divided | segmented.
Or the absorptive core does not need to have at least one among a peripheral groove part, a vertical groove part, and a horizontal groove part.

  This invention discloses the following absorbent articles further regarding embodiment mentioned above.

<1> The front core portion and the rear core portion located on both ends in the longitudinal direction and the width in the longitudinal intermediate portion between the front core portion and the rear core portion formed between a pair of constricted regions. A narrow intermediate core portion, and the intermediate core portion has a high basis weight portion formed at the center in the width direction, and has a lower basis weight than the high basis weight portion, and is formed around the high basis weight portion. A core wrap sheet comprising an absorbent core, a core covering portion covering the absorbent core, and a pair of constricted covering portions covering the pair of constricted regions. Absorbent article.
<2> The absorbent article according to <1>, wherein the low basis weight portion has a higher density than a side end portion located on the outer side in the width direction of the high basis weight portion and the side end portion. And a high-density part located between the side end part and the high basis weight part.
<3> The absorbent article according to the above <2>, wherein the surface sheet is disposed on the core wrap sheet, and the pressing groove formed on the surface sheet, the core wrap sheet, and the absorbent core. The high-density part is an absorbent article provided at the formation position of the compressed groove.
<4> The absorbent article according to any one of <1> to <3>, wherein an outer edge line of each of the pair of constricted covering portions includes the front core portion and the pair of constricted regions. More than the bisector of the line parallel to the width direction connecting the virtual line connecting the outer edge portions of the rear core portion and the outer edge line corresponding to the outer edge portion of the intermediate core portion. Absorbent articles located respectively on the side.
<5> The absorbent article according to any one of <1> to <4>, wherein the pair of constricted covering portions are opposed to each other without being bonded to each other in the thickness direction of the absorbent core. An absorbent article comprising a front side region and a back side region.
<6> The absorbent article according to <5>, wherein the front-side region and the back-side region are formed continuously from each other at a peripheral edge portion in the width direction of the pair of constricted covering portions. Sex goods.
<7> The absorbent article according to any one of <1> to <6>, wherein the front core portion and the rear core portion have a lower basis weight than the low basis weight portion. Sex goods.
<8> The absorbent article according to any one of <1> to <7>, wherein the high basis weight part is formed at least over the entire length of the intermediate core part.
<9> The absorbent article according to <8>, wherein the end portion in the longitudinal direction of the high basis weight portion has a shape in which a width gradually decreases toward the tip.
<10> The absorbent article according to any one of <1> to <9>, wherein the intermediate core portion has a basis weight lower than that of the low basis weight portion. An absorbent article further comprising a peripheral groove formed in the periphery.
<11> The absorbent article according to any one of <1> to <10>, further comprising a back sheet and a main body adhesive portion formed on an outer surface of the back sheet, The main body adhesive portion is an absorbent article having a width equal to or smaller than the width of the intermediate core portion and formed at a position facing the absorbent core in the thickness direction with the back sheet interposed therebetween.
<12> The absorbent article according to any one of <1> to <11>, wherein the absorbent article includes a pair of wing portions extending outward in the width direction from the intermediate core portion. Goods.
<13> The absorbent article according to <12>, wherein the wing part and the intermediate core part overlap with each other in the longitudinal direction.
<14> The absorbent article according to any one of <1> to <13>, wherein the core wrap sheet is non-extensible or hardly extensible.
<15> The absorbent article according to <14>, wherein the core wrap sheet has an elongation of 25% or less when loaded with 1 N per 50 mm width.
<16> The absorbent article according to any one of <1> to <15>, wherein the high basis weight portion extends to at least one of a front core portion and a rear core portion. Sex goods.
<17> The absorbent article according to any one of <1> to <16>, wherein the high basis weight portion has a longitudinal shape in a front-rear direction, and a maximum width thereof is 15 mm or more. , 60 mm or less, preferably 20 mm or more and 50 mm or less.
<18> The absorbent article according to any one of <1> to <17>, wherein a basis weight of the high basis weight part is 400 g / m ² or more and 1000 g / m ² or less, preferably Is an absorbent article of 500 g / m ² or more and 900 g / m ² or less.
<19> The absorbent article according to any one of <1> to <18>, wherein a basis weight of the low basis weight portion is 100 g / m ² or more and 700 g / m ² or less, preferably Is 200 g / m ² or more and 600 g / m ² or less.
<20> The absorbent article according to any one of <1> to <19>, wherein a width of the front core portion and the rear core portion is 60 mm or more and 100 mm or less, preferably 70 mm or more. Absorbent article which is 90 mm or less.
<21> The absorbent article according to any one of <1> to <20>, wherein the front core part and the rear core part have a thickness of 2 mm or more and 10 mm or less.
<22> The absorbent article according to any one of <1> to <22>, wherein a basis weight of the front core portion and the rear core portion is 90 g / m ² or more and 500 g / m ² or less. Is an absorbent article.
<23> The absorbent article according to any one of <1> to <23>, wherein the width of the intermediate core portion is 40 mm or more and 75 mm or less, preferably 50 mm or more and 70 mm or less. Absorbent article.
<24> The absorbent article according to any one of <1> to <24>, wherein a length in a longitudinal direction of the intermediate core portion is 60 mm or more and 180 mm or less, preferably 80 mm or more and 170 mm or less. There is an absorbent article.
<25> The absorbent article according to any one of <1> to <24>, which is a sanitary napkin.

1 ... Napkin (absorbent article)
DESCRIPTION OF SYMBOLS 11, 11A, 11B ... Absorber 12 ... Top sheet 13 ... Back sheet 15 ... Adhesive part 151 ... Main body adhesive part 16 ... Squeeze groove 20 ... Absorbent core 21 ... Front core part 22 ... Middle core part 22s ... Constriction area 23 ... Back core portion 24 ... high basis weight portion 241, 242 ... end portion 25 ... low basis weight portion 251 ... side end portion 252 ... high density portion 253 ... first high density portion 254 ... second high density portion 26 ... peripheral groove portion 22a , 22b ... taper portion 30 ... core wrap sheet 31 ... front covering portion 32 ... intermediate covering portion 33 ... rear covering portion 34 ... constricted covering portion 341 ... front side region 342 ... back side region

Claims (8)

A front core portion and a rear core portion positioned on both ends in the longitudinal direction, and an intermediate portion formed between the pair of constricted regions in the longitudinal intermediate portion and narrower than the front core portion and the rear core portion. A core portion, and the intermediate core portion has a high basis weight portion formed in the center in the width direction, and a low basis weight having a lower basis weight than the high basis weight portion and formed around the high basis weight portion. An absorbent core including a basis weight, and
An absorbent body comprising: a core covering portion covering the absorbent core; and a core wrap sheet having a pair of constricted covering portions covering the pair of constricted regions ;
A back sheet;
A main body adhesive portion formed on the outer surface of the back sheet,
The main body adhesive portion is disposed at a width equal to or smaller than the width of the intermediate core portion, is not disposed on the constricted covering portion, and is formed at a position facing the absorbent core in the thickness direction across the back sheet. Has been
A pair of wing portions extending outward in the width direction from the intermediate core portion are arranged so as to overlap with the intermediate core portion in the longitudinal direction.
Sanitary napkin . The sanitary napkin according to claim 1 ,
The pair of constricted covering portions are:
It includes a front side region and a back side region that face each other without being bonded to each other in the thickness direction of the absorbent core
Sanitary napkin . The sanitary napkin according to claim 1 or 2 ,
The intermediate core portion further includes a peripheral groove portion having a lower basis weight than the low basis weight portion and formed around the high basis weight portion.
Sanitary napkin . A sanitary napkin according to any one of claims 1 to 3 ,
The low basis weight part is
A side end located outside the width direction of the high basis weight portion;
A high-density portion having a higher density than the side end portion and located between the side end portion and the high basis weight portion.
Sanitary napkin . A sanitary napkin according to claim 4 ,
A surface sheet disposed on the core wrap sheet;
Further comprising: a pressing groove formed in the top sheet, the core wrap sheet and the absorbent core,
The high-density portion is provided at a position where the pressing groove is formed.
Sanitary napkin . A sanitary napkin according to any one of claims 1 to 5 ,
An outer edge line of each of the pair of constricted covering portions is an imaginary line connecting the outer edge portions of the front core portion and the rear core portion in each of the pair of constricted regions, and an outer edge line corresponding to the outer edge portion of the intermediate core portion. Are located outside the bisector of the line segment parallel to the width direction connecting
Sanitary napkin . The sanitary napkin according to any one of claims 1 to 6 ,
The high basis weight portion is formed over the entire length of at least the intermediate core portion.
Sanitary napkin . A sanitary napkin according to claim 7 ,
The longitudinal end portion of the high basis weight portion has a shape in which the width gradually decreases toward the tip.
Sanitary napkin .

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