JP7351657B2 - absorbent articles - Google Patents

Description

The present invention relates to absorbent articles.

Superabsorbent polymers (SAP) used in absorbent articles such as diapers may change color to yellow or brown due to oxidation in a hot and humid environment, causing the appearance of the absorbent article to appear deteriorated. This phenomenon is particularly likely to occur in subtropical and tropical regions such as Southeast Asia. Therefore, techniques have been proposed to suppress discoloration of superabsorbent polymers using antioxidants and the like to maintain a good appearance of absorbent articles.
For example, Patent Document 1 describes a technique that uses acrylic acid or a quinhydronation inhibitor with a low hydroquinone content, Patent Document 2 describes a technique that uses a reducing compound and a specific acid (salt), and Patent Document 3 describes a technique that uses a reducing compound and a specific acid (salt). Techniques using sulfinic acid derivatives have been described respectively.

Japanese Patent Application Publication No. 11-322846 Japanese Patent Application Publication No. 2003-52742 Special Publication No. 2006-521431

The techniques described in Patent Documents 1 to 3 have no choice but to use expensive superabsorbent polymers containing components that suppress discoloration, such as antioxidants, resulting in high prices of absorbent articles.
In view of the above points, the present invention relates to an absorbent article that can maintain a good appearance without using a superabsorbent polymer containing a component that suppresses discoloration.

The present invention provides an absorbent article comprising an absorbent body having an absorbent core and a core wrap sheet that covers the skin side and the non-skin side of the absorbent core, On at least one of the non-skin side, in L ^* a ^* b ^* color system, L ^* value: 40 or more and 100 or less, a ^* value: -12 or more and 3 or less, b ^* value: -24 or more and 3 or less. There is a member having a color, the absorbent core is an aggregate of a superabsorbent polymer and pulp fibers, the superabsorbent polymer is arranged on the skin side of the absorbent core, and the absorbent core is an aggregate of a superabsorbent polymer and pulp fibers. A joint between the absorbent core and the core wrap sheet is arranged on the skin side of the core , and at least a portion of the skin side of the absorbent core is provided with the high absorbent An absorbent article is provided in which a room surrounding a polymer is arranged and a region where the superabsorbent polymer is arranged is partitioned.

The absorbent article of the present invention can maintain a good appearance without using a superabsorbent polymer containing a component that suppresses discoloration.

1 is a perspective view of a diaper showing a preferred embodiment of an absorbent article according to the present invention. FIG. 2 is a partially cutaway developed plan view schematically showing a state in which the diaper shown in FIG. 1 is broken at a side seal portion, unfolded and stretched, and viewed from the skin side. 3 is a sectional view taken along line III-III in FIG. 2. FIG. FIG. 3 is a partially enlarged plan view schematically showing the arrangement of the chambers formed by the joints and the superabsorbent polymer on the skin side of the absorbent core. (A) is a partially enlarged sectional view showing a laminated state of an absorbent core, a skin-side member and a non-skin-side member of the absorbent core, and (B) is a modification of the diagram in (A). It is a partially enlarged sectional view showing the. It is a top view which shows the state in which the slit part is arrange|positioned to the absorbent core. FIG. 2 is a cross-sectional view in the thickness direction of the absorbent core, schematically showing a state in which core wrap sheets disposed on the skin side and the non-skin side of the absorbent core are adhered to each other at a slit portion.

A diaper as a preferred embodiment of the absorbent article of the present invention will be described below with reference to the drawings.

In the present invention, the side that contacts the wearer's skin when the absorbent article is worn is referred to as the skin side, skin contact side, or surface side, and the side opposite to this is referred to as the non-skin side, non-skin contact side. It is called the front side or the back side. These terms are used to indicate relative positional relationships in the component structure of the absorbent article, even for members that do not have a surface that comes into contact with the wearer's skin when the absorbent article is worn. Further, the normal direction of the front or back surface of the absorbent article is referred to as the thickness direction.

As shown in FIG. 1, the diaper 10 of this embodiment has an absorbent main body 1 and an exterior body 2. The exterior body 2 has a front exterior part 21 and a rear exterior body 22 corresponding to the front side and the rear side of the wearer, respectively. The front side is the wearer's ventral side, and the rear side is the wearer's back side. The front exterior body 21 and the rear exterior body 22 are horizontally long, and their respective side edges are overlapped and joined at the side seal portion 11 to form an annular waist portion 10D of the diaper 10. A portion of the absorbent body 1 extending from the exterior body 2 forms an intermediate portion 10C of the diaper 10. The diaper 10 has a waist opening 12 that is open above the waist portion 10D, and a pair of leg openings 13, 13 that are open on both left and right sides of the intermediate portion 10C.

FIG. 2 shows the diaper 10 in an expanded state with the diaper 10 broken at the side seal portions 11, 11. Here, the unfolded state refers to a state in which each part is stretched and the absorbent article is spread out into a flat shape.
In the unfolded state, the diaper 10 is divided into a front side part 10F, a middle part 10C, and a rear side part 10R. A laterally elongated front exterior part 21 and a rear exterior body 22 are arranged in correspondence with the front side part 10F and the rear side part 10R, respectively. The vertically long absorbent main body 1 is disposed with its longitudinal direction facing the front side 10F, middle section 10C, and rear side 10R of the diaper 10. In this arrangement, the absorbent main body 1 has a longitudinal direction Y corresponding to the direction in which the front side, crotch, and back side of the wearer are connected, and a width direction X that is orthogonal to the longitudinal direction Y.

As shown in FIG. 3, the absorbent main body 1 constituting the diaper 10 includes a liquid-permeable top sheet 3 on the skin side, a leak-proof back sheet 4 on the non-skin side, and the top sheet 3 and the back sheet. It has a liquid-retaining absorbent body 5 disposed between the liquid absorbent body 4 and the absorbent body 4 . The absorbent body 5 has an absorbent core 6 made of an aggregate of a superabsorbent polymer 67 and pulp fibers 68, and a core wrap sheet 7 that covers the outer periphery of the absorbent core 6. The core wrap sheet 7 is made of a hydrophilic material, such as hydrophilic paper or nonwoven fabric.

Moreover, in this embodiment, a pair of side sheets 9 are provided on both sides of the absorbent main body 1 in the longitudinal direction Y. A three-dimensional gather portion 92 is formed by disposing an elastic member 91 in a stretched state at the inner end of the side sheet 9 in the width direction X. Further, a leg gather portion 94 is formed by arranging an elastic member 93 in a stretched state at the outer end of the side sheet 9 in the width direction X. Furthermore, in the absorbent main body 1 of this embodiment, an exterior nonwoven fabric 48 is disposed on the non-skin side of the back sheet 4.

As shown in FIG. 2, the absorbent core 6 has a longitudinal direction Y and a width direction X perpendicular to the longitudinal direction, similarly to the absorbent main body 1. As shown in FIGS. 2 and 3, the core wrap sheet 7 extends in the width direction X while covering the entire absorbent core 6 in the longitudinal direction Y, and covers the skin side, both sides, and non-skin side of the absorbent core 6. The surface side (outer periphery) is covered. Specifically, the skin side core wrap sheet 71 covers the skin side of the absorbent core 6, and the non-skin side core wrap sheet 72 covers the non-skin side of the absorbent core 6. The non-skin side core wrap sheet 72 further extends in the width direction It is joined. This laminated portion forms a laminated portion 75 extending over the entire length of the absorbent core 6 in the longitudinal direction Y at two locations on both ends of the absorbent core 6 in the width direction X. In FIG. 3, two laminated portions 75 of the core wrap sheet 7 are arranged on the skin side of the absorbent core 6, but the laminated portions 75 are not limited thereto. For example, they may be arranged on the non-skin side, or one or three or more may be arranged on the non-skin side or the skin side. When one laminate 75 is disposed on the non-skin side of the absorbent core 6, for example, one core wrap sheet is rolled down from the skin side of the absorbent core 6 to both sides and to the non-skin side. An example of this is an embodiment in which the ends are laminated together. In this case, of one core wrap sheet, the one placed on the skin side of the absorbent core 6 is the skin side core wrap 71, and the one placed on the non-skin side of the absorbent core 6 is the non-skin side core wrap 71. It is called a skin side core wrap sheet 72.

As shown in FIG. 3, a superabsorbent polymer 67 is disposed on the skin side of the absorbent core 6. The superabsorbent polymer 67 is divided into rooms on the skin side of the absorbent core 6 by joints 55, which will be described later. This superabsorbent polymer 67 is preferably uniformly distributed on the skin surface side of the absorbent core 67. Here, "uniform" means that the amount of superabsorbent polymer 67 falling off from the skin surface of the absorbent core 6 is measured for each section using the method below, and the amount of falling off of each section is compared to the average amount of falling off of all sections. This means that the ratio of the difference between the amount and the average shedding amount of all sections is within ±100% as a basis weight ratio. Further, the ratio of the shedding amount of each section to the average shedding amount of all the sections is preferably within ±50%, more preferably within ±30%, as a basis weight ratio.

(Method for measuring the distribution of superabsorbent polymer 67 on the skin side of absorbent core 6)
(1) Divide the absorbent article containing the absorbent body into two horizontal sections and three vertical sections in a plan view.
(2) Cut off a portion of the absorbent core on the skin side of one section that is closer to the skin-contacting surface (for example, the core wrap sheet and the top sheet) to expose the absorbent core. Shake 20 times with the exposed part facing down, measure the mass of the superabsorbent polymer that has fallen off, and convert it into basis weight (g/m ² ). This makes it possible to compare the amount of superabsorbent polymer shedding in each section by excluding the effects of the presence or absence of slits and differences in area due to the shape of the absorbent core (for example, hourglass shape).
(3) Perform the process in (2) above in each section. Next, the average amount of shedding (converted to basis weight) of all the sections is calculated from the measured values in each section, and the amount of shedding (converted to basis weight) of each section and the amount of shedding (converted to basis weight) of all the sections relative to the average amount of shedding (converted to basis weight) are calculated. Calculate the ratio of the difference in average shedding amount (based on basis weight). That is, [falling amount of each section - average falling amount of all sections]/[average falling amount of all sections] is calculated.

Note that the superabsorbent polymer 67 may be arranged not only on the skin side of the absorbent core 6 but also inside the absorbent core 6 . Inside, the superabsorbent polymer 67 is preferably dispersed in the thickness direction and planar direction of the absorbent core 6, and is supported between the pulp fibers 68.

In addition, as shown in FIGS. 3 and 4, a joint 55 between the absorbent core 6 and the core wrap sheet 7 (skin side core wrap sheet 71) is arranged on the skin side of the absorbent core 6. ing. The joint portion 55 is formed by applying adhesive. Adhesives that are commonly used in this type of article can be used, such as hot-melt adhesives. Furthermore, the adhesive can be applied by a method commonly used for this type of article. Examples include spray coating and gravure coating. In order to maintain liquid absorbency and maintain the uniform arrangement of the above-mentioned superabsorbent polymer 67, it is preferable that the adhesive is applied linearly and intermittently to the skin surface of the absorbent core 6. It is more preferable to apply the coating in a spiral manner. That is, it is preferable that the joint parts 55 formed by the adhesive are arranged intermittently in a linear manner with respect to the skin surface of the absorbent core 6, and preferably in a spiral shape.

As shown in FIGS. 3 and 4, a chamber 56 surrounding the superabsorbent polymer 67 by the joint 55 is arranged in at least a portion of the skin surface side of the absorbent core 6. That is, the joint portion 55 serves as a pillar that partitions the area where the superabsorbent polymer 67 is arranged on the skin side of the absorbent core 6.
The room 56 includes a space 56R that is vertically sandwiched between the skin surface of the absorbent core 6 and the core wrap sheet 7 (skin surface side core wrap sheet 71) in a region surrounded by the joint portion 55. In a space 56R provided in the room 56, a plurality of superabsorbent polymers 67 are arranged in a planar direction. A plurality of these chambers 56 are arranged on the skin surface of the absorbent core 6. Thereby, a region where the superabsorbent polymer 67 is arranged is defined on the skin side of the absorbent core 6.

The above-mentioned chambers 56 suitably suppress movement of the superabsorbent polymer 67 disposed on the skin surface side of the absorbent core 6. That is, the superabsorbent polymer 67 is made difficult to move between the rooms 56 and 56 partitioned by the joint portion 55 acting as a pillar. Normally, the diaper 10 is folded after manufacturing, compressed and stored in a packaging bag for sale, and then subjected to various external forces in various situations such as being transported and sold, opened after purchase, and used. Even in that case, the arrangement of the chambers 56 by the joints 55 suppresses the movement of the superabsorbent polymer 67, making it easier to maintain the uniformity of the superabsorbent polymer disposed on the skin side of the absorbent core 6.
As a result, even if the superabsorbent polymer 67 is discolored, the color after discoloration (for example, yellow or brown) is prevented from existing as a lump. In addition, since the superabsorbent polymer 67 is uniform without clumping on the skin side of the absorbent core 6, the excreted liquid can be quickly absorbed and the excreted liquid can be efficiently transferred from the skin side to the inside of the absorbent core 6. penetration is achieved. This improves the absorption performance of the entire absorbent core 6.

As described above, a plurality of such chambers 56 are arranged in at least a portion of the skin surface side of the absorbent core 6. The area in which the plurality of rooms 56 are arranged is selected from the viewpoint of maintaining uniform arrangement of the superabsorbent polymer 67, making discoloration (for example, yellow or brown) less noticeable, and achieving high liquid absorption. , it is preferable that it is in the range of 1/3 of the absorbent body, more preferably that it is in the range of 3/4 of the absorbent body, and even more preferably that it is in the entire area on the skin side of the absorbent core 6. It is preferable that a liquid-receiving area, which will be described later, be included in a range of 1/3 of the absorber and a range of 3/4 of the absorber.

It is preferable that the above-mentioned chambers 56 form rows in the longitudinal direction Y of the absorbent core 6, and the rows are arranged in three or more rows in the width direction X. Thereby, it is possible to effectively suppress movement, uneven distribution, and falling off of the superabsorbent polymer 67 in the width direction X, and maintain uniform arrangement. From this point of view, it is more preferable that four or more rows are arranged in the width direction X, and it is even more preferable that five or more rows are arranged. Further, from the viewpoint of not impeding absorption performance, the rows are preferably arranged in 10 or less rows in the width direction X, more preferably 8 or less rows, and 6 or less rows are arranged in the width direction. More preferred. Specifically, the columns are preferably arranged in 3 to 10 columns in the width direction X, more preferably 4 to 8 columns, and preferably 5 to 6 columns. More preferred.
In addition, the number of the chambers 56 in one row (the number in the longitudinal direction Y) is determined from the viewpoint of effectively suppressing the movement, uneven distribution, and falling off of the superabsorbent polymer 67 in the longitudinal direction Y and maintaining a uniform arrangement. , preferably 5 or more, more preferably 10 or more, and even more preferably 20 or more. Further, the number of the above-mentioned chambers 56 in one row (the number in the longitudinal direction Y) is preferably 100 or less, more preferably 50 or less, and still more preferably 30 or more from the viewpoint of ensuring absorption performance. Specifically, the number of the above-mentioned chambers 56 in one row (the number in the longitudinal direction Y) is preferably 5 or more and 100 or less, more preferably 10 or more and 50 or less, and 20 or more and 30 or less. More preferred.

The above-mentioned room 56 has a planar shape bordered by linear joints 55, and the planar shape can have various shapes. Examples include circles, ellipses, polygons, etc. In particular, the viewpoint is to maintain uniform arrangement of the superabsorbent polymer 67, to suppress movement of the superabsorbent polymer 67 between the chambers 56, and to prevent gel blocking from occurring on the skin side of the absorbent core 6 when liquid is absorbed. Therefore, the planar shape of the room 56 is preferably circular or oval. From this point of view, it is preferable that the joint portions 55 are arranged in a spiral shape. By arranging the joint portions 55 in a spiral shape, the circular or elliptical chambers 56 can be arranged without gaps, and the superabsorbent polymer 67 can be efficiently arranged.
The line width of the linear joint 55 is preferably 5 mm or less, more preferably 3 mm or less, and 1 mm or less, from the viewpoint of maintaining the liquid absorbency of the absorbent core 6 and maintaining the uniform arrangement of the superabsorbent polymer 67. is even more preferable. In addition, from the viewpoint of suppressing the movement of the superabsorbent polymer 67 between the chambers 56, the line width of the linear joint 55 is preferably 0.1 mm or more, more preferably 0.3 mm or more, and 0.1 mm or more, more preferably 0.3 mm or more. .5 or more is more preferable. Specifically, the line width of the linear joint portion 55 is preferably 0.1 or more and 5 mm or less, more preferably 0.3 mm or more and 3 mm or less, and even more preferably 0.5 mm or more and 1 mm or less.
Furthermore, from the viewpoint of suppressing the superabsorbent polymer 67 from falling off and maintaining the uniform arrangement of the superabsorbent polymer 67 when the diaper 10 is used, the joints 55 constituting the above-mentioned chambers 56 are connected to the absorbent core 6. Preferably, it is also arranged at the outer edge 69 of the skin surface (see FIGS. 3 and 6). The "outer edge 69 of the skin surface of the absorbent core 6" as used herein refers to the edge portion along the outer periphery of the absorbent core 6 that is visible when the absorbent core 6 is viewed in plan from the skin surface side. In this case, it is preferable that at least a portion of the outer edge 69 has the joint portion 55 . For example, the ratio of the joint portion 55 to the total length of the outer edge 69 of the skin surface of the absorbent core 6 is preferably 5% or more, preferably 20% or more, and still more preferably 50% or more. The larger the ratio is, the more preferable it is. Specifically, the ratio is preferably 5% or more and 100% or less, preferably 20% or more and 100% or less, and still more preferably 50% or more and 100% or less.

The basis weight of the joint 55 on the skin side of the absorbent core 6 (the basis weight of the adhesive forming the joint 55) maintains the liquid absorbency of the absorbent core 6, and ensures uniform arrangement of the superabsorbent polymer 67. From the viewpoint of maintaining this, it is preferably 20 g/m ² or less, more preferably 15 g/m ² or less, and even more preferably 10 g/m ² or less. In addition, the basis weight of the joint portion 55 on the skin side of the absorbent core 6 is determined to ensure adhesive strength between the absorbent core 6 and the skin side core wrap sheet 71, and to ensure the adhesive strength between the rooms 56 and 56 of the superabsorbent polymer 67. From the viewpoint of suppressing the movement of , it is preferably 1 g/m ² or more, more preferably 3 g/m ² or more, and even more preferably 5 g/m ² or more. Specifically, the basis weight of the joint portion 55 on the skin side of the absorbent core 6 is preferably 1 g/m ² or more and 20 g/m ² or less, more preferably 3 g/m ² or more and 15 g/m ² or less, and 5 g/m 2 or more. /m ² or more and 10 g/m ² or less is more preferable.

(Method of measuring the basis weight of the joint portion 55 on the skin side of the absorbent core 6)
The non-skin side of the core wrap sheet 7 and the adhesive coated area (the area where the joint 55 is arranged) on the skin side of the absorbent core 6 are coated with a predetermined thickness (from the skin side of the core wrap sheet 7). Cut it out at the thickness where it is impregnated with adhesive (for example, 5 mm) and remove the pulp fibers and superabsorbent polymer. An adhesive (for example, a hot melt adhesive) is extracted from the coated area using a solvent, the extracted solution is dried under reduced pressure using a rotary evaporator, and the mass of the obtained adhesive is measured.
The basis weight of the joint portion 55 on the skin side of the absorbent core 6 is calculated by dividing the measured mass of the adhesive by the area between the widthwise end and the longitudinal end of the coated portion. .
Note that the solvent may be appropriately selected depending on the type of adhesive and the like. When the adhesive to be measured is, for example, a hot melt adhesive, examples of the solvent include toluene, methyl ethyl ketone, and heptane.

In addition, the basis weight of the superabsorbent polymer 67 disposed on the skin side of the absorbent core 6 is 10g/10g/cm from the viewpoint of maintaining the liquid absorbency of the absorbent core 6 and from the viewpoint of making the color after discoloration less noticeable. m ² or more is preferable, 20 g/m ² or more is more preferable, and even more preferably 30 g/m ² or more. In addition, the basis weight of the superabsorbent polymer disposed on the skin side of the absorbent core 6 is 100g/100g from the viewpoint of maintaining liquid permeability into the absorbent core 6 and suppressing the occurrence of gel blocking. m ² or less is preferable, 80 g/m ² or less is more preferable, and 60 g/m ² or less is still more preferable. Specifically, the basis weight of the superabsorbent polymer disposed on the skin side of the absorbent core 6 is preferably 10 g/m ² or more and 100 g/m ² or less, and 20 g/m ² or more and 80 g/m ² or less. More preferably, it is 30 g/m ² or more and 60 g/m ² or less.

Furthermore, in the diaper 10, at least one of the skin side and the non-skin side of the absorbent core 6 has L ^* value: 40 or more and 100 or less, a ^* value: -12 or more in the L ^* a ^* b ^* color system. 3 or less, b ^* value: Members having colors in the range of -24 or more and 3 or less are arranged. The above color preferably has an L ^* value of 60 or more and 80 or less, an a ^* value of -9 or more and 0 or less, and a b ^* value of -15 or more and -6 or less in the L ^* a ^* b ^* color system. More preferably, L ^* value: 65 or more and 75 or less, a ^* value: -6 or more and -3 or less, and b ^* value: -12 or more and -9 or less. In this specification, the above-mentioned color is also referred to as a "covering color" because it is present in a member that is superimposed on the skin side or the non-skin side of the superabsorbent polymer 67. Note that the L ^* a ^* b ^* color system is defined in JIS-Z-8729, where L ^* indicates brightness and a ^* and b ^* indicate color direction. Each value is shown as a value from plus to minus. The larger the value of L ^* , the brighter it is. Regarding a ^* , a positive value indicates approximately the red direction, and a negative value indicates approximately the green direction. Regarding b ^* , a positive value indicates a substantially yellow direction, and a negative value indicates a substantially blue direction.

The above-mentioned enveloping color is a color that is complementary to the color of the superabsorbent polymer 67 after discoloration (for example, yellow or brown). Colors that are complementary appear to overlap when the diaper 20 is viewed from the outside. In other words, the colors appear mixed. As a result, from the outside of the diaper 10, especially from the skin side, the color saturation of the superabsorbent polymer 67 after discoloration is lowered and becomes less noticeable. More specifically, when materials that easily transmit light overlap, such as fiber material members such as non-woven fabrics or fill material members, the color of the superabsorbent polymer 67 after discoloration is the same as that of the outer covering color. projected on. As a result, from the outside of the diaper 10, complementary colors appear mixed, and the saturation of the color after the superabsorbent polymer 67 changes color is lowered, making it less noticeable.
In addition, since the superabsorbent polymer 67 on the skin side of the absorbent core 6 is arranged flat in the plane direction, the color after discoloration does not form a lump and is dispersed in the above-mentioned covering color. appear. Therefore, when the diaper 10 is viewed from the outside, especially when viewed from the skin side, complementary colors are prevented from appearing as clusters and adjacent to each other. Normally, when complementary colors are clustered and adjacent to each other, saturation is emphasized, but the above arrangement makes it possible to avoid such emphasis on saturation between complementary colors. From this point of view, it is preferable that the superabsorbent polymer 67 is uniformly distributed as described above.

In addition, the presence of the member having the above-mentioned covering color provides a good appearance of the diaper 10 from the initial stage of use, regardless of the presence or absence of discoloration of the superabsorbent polymer 67 and the degree of discoloration, which is preferable.

(Method for measuring each value of L ^* a ^* b ^* color system in envelope color)
The member to be measured is removed from the absorbent article and measured. Specifically, after weakening the adhesive used to bond the member to be measured and another member using cooling means such as cold spray, the member to be measured is carefully peeled off and taken out.
The measurement is performed by placing a white sheet underneath and using a color difference meter such as a simple spectroscopic color difference meter NF333 (trade name) manufactured by Nippon Denshoku Industries Co., Ltd. In the above measurement method using the simple spectrophotometer NF333, a stapler-type ND110 sensor with a diameter of 4 mm is attached, an O-ring (small) is used at the tip of the sensor, a light source is C/2, and a viewing angle is 2. Measured in °.
When measuring, the sensor part of the color difference meter is placed directly on the measurement site of the member to be measured.

As shown in FIG. 5(A), examples of skin-side members having a covering color include the top sheet 3 and the skin-side core wrap 71. In addition, as shown in FIGS. 2 and 3, a side sheet 9 that partially overlaps the absorbent core 6 is also included. Moreover, as shown in FIG. 5(B), when there is an intermediate member 35 between the top sheet 3 and the absorbent core 5, the intermediate member 35 is also included. It is preferable that the intermediate member 35 is made of a hydrophilic fiber material that has the function of quickly absorbing the excrement liquid permeated through the topsheet 3 on a wide surface of the absorbent body 5 while diffusing it in the planar direction.
In addition, examples of the non-skin side members on which the wrapping color is arranged include the back sheet 4, the non-skin side core wrap sheet 72, and the exterior nonwoven fabric 48. In addition, as shown in FIGS. 1 and 2, the aforementioned exterior body 2 is also included in the non-skin side member.
The covering color may be arranged on one of these skin side and non-skin side members, or the covering color may be arranged on two or more members. It is preferable that two or more members are coated with a covering color because the above-mentioned visual effects are further enhanced. For example, it is preferable that the covering color is applied to one or more members on both the skin side and the non-skin side.
From the viewpoint of making it easier to match the enveloping color to the color of the superabsorbent polymer 67 after discoloration (L ^* a ^* b ^* each value of the color system), and from the viewpoint of making the above-mentioned visual effect more effective, the color should be as high as possible. It is preferable that the covering color is arranged on a member close to the absorbent polymer 67. For example, the priority order of the members to which the covering color is arranged on the skin side is: skin side core wrap sheet 71; intermediate member 35; top sheet 3; side sheet 9. Furthermore, the priority order of the members to which wrapping colors are arranged on the non-skin side is: non-skin side core wrap sheet 72; back sheet 4; exterior nonwoven fabric 48, and exterior body 2. It is preferable that at least the core wrap sheet 7 has a covering color on both the skin side and the non-skin side. In particular, it is preferable that at least the skin-side core wrap sheet 71 is provided with a covering color.
Furthermore, the covering color may be applied to the entire member, or may be applied to a part of the member. When disposed in a portion, it is preferable that the absorbent core 6 be disposed including the area overlapping with the absorbent core 6. In consideration of unintentional falling off of the superabsorbent polymer 67, it is preferable that the covering color be applied to the entire member.

When the intermediate member 35 mentioned above is provided as a member on the skin side of the absorbent core 6, the above-mentioned covering color may or may not be arranged on the intermediate member 35. If not, the covering color is placed on another skin side member (for example, a core wrap sheet). The intermediate member 35 can keep the discolored color of the superabsorbent polymer 67 away from the skin side of the diaper 10 even when there is no enveloping color. As a result, in conjunction with the above-mentioned effect due to the covering color in other members, the saturation of the color of the superabsorbent polymer 67 after discoloration is further lowered from the outside of the diaper 10 (skin side). This further enhances the effect of making it less noticeable.
Further, when the intermediate member 35 is not provided with the above-mentioned enveloping color, it is preferable that an achromatic color having an L ^* value of 50 or more and 80 or less, that is, a gray color, is provided. Thereby, the color of the superabsorbent polymer 67 after discoloration can be made less noticeable. Generally, by overlaying gray color, you can reduce the saturation of the color, and by overlapping the discolored part of the polymer and the enveloping color, and by overlaying the gray color on the part where the saturation has decreased, the discolored part can be further visualized. It can be made difficult to stand.

As described above, in the diaper 10, the superabsorbent polymer 67 is arranged on the skin side of the absorbent core 6, and the member having the above-mentioned covering color is arranged. In the state before use of the diaper 10, the L ^* value of the absorber 5 visible from the skin side of the diaper 10 is preferably 85 or less, more preferably 80 or less, and still more preferably 75 or less. preferable. This makes it difficult to damage the appearance of the polymer before and after discoloration. Further, the L ^* value as seen from the skin side of the diaper 10 is preferably 60 or more, more preferably 65 or more, and even more preferably 70 or more. This maintains the effect of not impairing the appearance of the polymer before and after discoloration, while suppressing darkening of the appearance before use. Specifically, in the state before use of the diaper 10, the L ^* value seen from the skin side of the diaper 10 is preferably 60 or more and 85 or less, more preferably 65 or more and 80 or less, and 70 or more. More preferably, it is 75 or less.
Note that the above L ^* value that is visible from the skin side of the diaper 10 can also be measured using, for example, a simple spectrophotometer NF333 (trade name) manufactured by Nippon Denshoku Industries, Ltd.

Further, in the diaper 10, in the absorbent core 6, it is preferable that the basis weight of the superabsorbent polymer 67 increases from the non-skin side to the skin side. Note that the superabsorbent polymer 67 mentioned here includes one that is mixed with the pulp fibers 68 in the absorbent core 6 and one that is arranged on the skin side of the absorbent core 6.
The above-mentioned "increasing" means that when the absorbent core 6 is viewed in the thickness direction, the superabsorbent polymer 67 is relatively more in the layer closer to the skin side than in the layer closer to the non-skin side. It means that it is contained in a large amount, and this amount is indicated by the basis weight. The uneven distribution of the highly absorbent polymer 67 may be in a manner in which it gradually increases from the non-skin side toward the skin side, or in a manner in which it increases in stages. Comparing at least the outermost layer on the non-skin side and the outermost layer on the skin side of the absorbent core 6, it is preferable that the amount of the superabsorbent polymer 67 contained in the outermost layer on the skin side is larger. Thereby, together with the superabsorbent polymer 67 disposed on the skin side of the absorbent core 6 described above, a high absorption capacity of the diaper 10 can be ensured, and rapid absorption and leakage prevention can be improved.

Moreover, from the same viewpoint, it is more preferable that the superabsorbent polymer 67 is included in the absorbent core 6 in the following manner. That is, first, as shown in FIG. 3, the absorbent core 6 is divided into a front surface portion 61 located on the skin side and a back surface portion 62 located on the non-skin side in the thickness direction. This division is made by dividing the absorbent core 51 into two equal parts in the thickness direction. At this time, the basis weight of the superabsorbent polymer 67 in the surface portion 61 is preferably 40 g/m ² or more, more preferably 60 g/m ² or more, and still more preferably 80 g/m ² or more. preferable. Further, the basis weight of the superabsorbent polymer 67 in the surface portion 61 is preferably 250 g/m ² or less, and 200 g/m ² or less, from the viewpoint of preventing gel blocking due to high polymer density. is more preferable, and even more preferably 150 g/m ² or less. Specifically, the basis weight of the superabsorbent polymer 67 in the surface portion 61 is preferably 40 g/m ² or more and 250 g/m ² or less, more preferably 60 g/m ² or more and 200 g/m ² or less. It is preferably 80 g/m ² or more and 150 g/m ² or less.

(Method for measuring basis weight of superabsorbent polymer 67 in absorbent core 6)
First, while observing the cross section of the measurement target portion of the absorbent core 6 with a microscope, it is divided into two equal parts in the thickness direction, and each portion of the front surface portion 61 and the back surface portion 62 is sampled.
For each sampled part, the mixture of superabsorbent polymer 67 and pulp fiber 68 was quantified based on the method for quantifying fibers and/or water absorbent polymer described in Japanese Patent No. 4225821, and the mixture of superabsorbent polymer 67 and pulp fiber 68 was quantified. Calculate the mass.
Specifically, after measuring the mass of each sampled part, the superabsorbent polymer 67 is reduced in molecular weight in each part. The molecular weight of the superabsorbent polymer 67 can be reduced by ultraviolet irradiation. At that time, a mixture of the superabsorbent polymer 67 and pulp fibers 68 from each sampled part is placed in a mesh bag or the like and immersed in an aqueous solution containing ascorbic acid and riboflavin. After the superabsorbent polymer is swollen by immersion, the mesh bag is taken out from the aqueous solution, and the above ultraviolet rays are irradiated to lower the molecular weight of the superabsorbent polymer 67. Next, components generated by lowering the molecular weight are removed by washing with water. After thoroughly washing the removed mesh bag with water, it is dehydrated and dried, and its mass is measured. The mass of the pulp fibers 68 is calculated by subtracting the mass of the mesh bag alone from the measured mass, and the mass of the superabsorbent polymer 67 is obtained by subtracting the mass of the pulp fibers 68 from the mass of each portion initially measured. Based on these, the basis weight of the superabsorbent polymer 67 in each part is obtained by dividing by the area of each part. The average value obtained by performing the above measurement three times is defined as the basis weight of the superabsorbent polymer 67 in each portion of the front surface portion 61 and the back surface portion 62.

Further, in the diaper 10, the absorbent body 5 preferably has a compressed portion (not shown) formed by applying a certain amount of compression in the thickness direction by embossing or the like. This can prevent the superabsorbent polymer 67 from moving to a position where the color after discoloration is noticeable (for example, the end of the absorbent core 6).
In the compression section, the pulp fibers 68 are compressed, which tends to restrict the movement of the superabsorbent polymer 67. As long as this effect is achieved, the depth of the compressed portion can be set as appropriate, and may be a depth that reaches the back surface portion 62 of the absorbent core 6. From the viewpoint of preventing the absorbency of the superabsorbent polymer 67 from being inhibited by compression, it is preferable that the compressed portion is deep enough to remain in the surface portion 61 of the absorbent core 6 on the skin side of the absorbent body 5 . Further, it is preferable that the compressed portion is present only on the surface portion 61 from the viewpoint of not reducing the softness of the absorbent core 6. This compression part can be formed linearly in the plane direction of the absorbent body 5 on the skin side of the absorbent body 5 including the absorbent core 6 and the core wrap sheet 7, for example. Examples of the linear compressed portions include those arranged in a diagonal lattice shape with respect to the longitudinal direction Y and the width direction X. The shape of the compressed portion is not particularly limited as long as it achieves the above-mentioned effect, and examples include the above-mentioned diagonal lattice shape, staggered shape, and wavy shape. Further, the compressed portion is not limited to the case where it is provided only in the absorbent body 5, but may be one in which the absorbent body 5 and the top sheet 3 are compressed together, for example.

Moreover, in the diaper 10, as shown in FIG. 6, it is preferable that the absorbent core 6 is provided with a slit portion 8. The slit portion 8 is a space formed in the thickness direction from the skin surface side, where the amount of pulp is smaller than the surrounding area in the absorbent core 6. The slit portion 8 may be a cut-shaped portion or a groove having a predetermined width. At this position of the slit portion 8, the excretory fluid can easily permeate the absorbent core 6 in the thickness direction. Thereby, the diaper 10 can improve its quick liquid absorption and retention properties and its wet back prevention properties. In other words, the rapid liquid absorption and retention properties and the wetback prevention properties can be improved at the same time as the discoloration of the superabsorbent polymer 67 is made less noticeable.

The slit portion 8 preferably has a depth that reaches from the skin side of the absorbent core 6 to the back surface portion 62 from the viewpoint of improving the above-mentioned liquid absorption and retention properties and wet back prevention properties. More preferably, the hole is a through hole extending from the skin side to the non-skin side. In addition, the slit portion 8 is preferably located in the liquid receiving region Q of the absorbent core 6 from the same viewpoint as above.
The "liquid receiving area Q" referred to here is an area that directly receives excreted liquid such as urine. In the diaper 10, the liquid receiving area Q is an area within 3.5 cm in the left and right width directions from a line S1 that bisects the length in the width direction X, and bisects the length in the longitudinal direction Y. This is an area within 8 cm from the line M1 in the front direction. Further, when the absorbent article of the present invention is a sanitary napkin for daytime use, the liquid-receiving region Q is an intermediate portion obtained by dividing the absorbent core 6 into three equal parts in the longitudinal direction Y, and the absorbent core 6 is divided into three equal parts in the width direction The area is within 2.5 cm in the left and right width direction from the line that bisects the length of. When the absorbent article of the present invention is a sanitary napkin equipped with a wide rear flap that covers the buttocks, such as for night use, it is divided into four equal parts in the longitudinal direction Y, and the second part is the length of the part in the width direction X. The area within 2.5 cm in the left and right width direction from the line that bisects the area becomes the liquid receiving area Q. Further, when the absorbent article of the present invention is a urine absorbing pad or an incontinence pad, the settings are similar to the diaper 10.

In FIG. 6, the slit portions 8 have a length extending back and forth in the longitudinal direction Y from the liquid receiving region Q, and three slit portions 8 are arranged side by side in the width direction X. Although the arrangement and number of the slit portions 8 are not limited to these, the embodiment shown in FIG. 6 is preferable from the viewpoint of improving the above-mentioned liquid absorption and retention properties and wet back prevention properties.

When there are multiple slit portions 8, the width of each slit portion 8 (groove width and length in the width direction X) may be the same or different. When the width of each slit portion 8 is the same, the excretory fluid can be easily diffused uniformly and quickly within the absorbent core 6. This is preferable because a wider area of the absorbent core 6 can be utilized for liquid absorption. In order to make this effect more pronounced, the width of each slit portion 8 is preferably 1 mm or more, more preferably 3 mm or more. Further, the width of each slit portion 8 is preferably 20 mm or less, more preferably 15 mm or less. Specifically, the width of each slit portion 8 is preferably 1 mm or more and 20 mm or less, more preferably 3 mm or more and 15 mm or less. Note that even when the widths of each slit section 8 are different from each other, it is preferable that the width of each slit section 8 is within the above range.

When there are multiple slit portions 8, the length of each slit portion 8 (length in the longitudinal direction Y) may be the same or different. When the lengths of the slits 8 are the same, it becomes easier for the excretory fluid to diffuse uniformly and quickly within the absorbent core 6. This is preferable because a wider area of the absorbent core 6 can be utilized for liquid absorption. In order to make this effect more pronounced, the length of each slit portion 8 is preferably 50 mm or more, more preferably 100 mm or more. Further, the length of each slit portion 8 is preferably 350 mm or less, more preferably 300 mm or less. Specifically, the length of each slit portion 8 is preferably 50 mm or more and 350 mm or less, more preferably 100 mm or more and 300 mm or less. Note that even if the lengths of each slit section 8 are different from each other, it is preferable that the length of each slit section 8 is within the above range.

The length of each slit portion 8 is preferably as follows when the absorbent core 6 is divided into three equal parts in the longitudinal direction Y and divided into a front portion F, a middle portion C, and a rear portion R.
When the lengths of the slit parts 8 are the same, the positions of the ends T1 on the front part F side of the slit parts 8 may be the same or different. Similarly, the positions of the ends T2 on the rear R side of each slit portion 8 may be the same or different. In FIG. 6, the positions of the ends T1 of each slit part 8 on the front part F side are the same, and the positions of the ends T2 of each slit part 8 on the rear part R side are the same.

It is preferable that each slit portion 8 is absent in the rear portion R. Thereby, a balance can be achieved between the liquid absorbing power of the absorbent core 6, the liquid diffusibility in the absorbent core 6, and the good feeling of wearing the diaper 10. In particular, the separation distance between the end T2 of each slit portion 8 on the side of the rear portion R and the boundary position T3 between the intermediate portion C and the rear portion R in the absorbent core 6 is preferably 5 mm or more, and 10 mm or more. It is more preferably 50 mm or less, and more preferably 45 mm or less. Specifically, the distance between the end T2 on the rear R side of each slit portion 8 and the boundary position T3 is preferably 5 mm or more and 50 mm or less, and more preferably 10 mm or more and 45 mm or less. This makes it easier for liquid to diffuse in the high tsubo region 6H. In addition, the absorbent core 6 is easily bent and deformed, and the diaper 10 feels even better when worn.

In particular, if each slit section 8 is absent on the rear side R of the absorbent core 6 from the position corresponding to the wearer's feces excretion area, excreted feces may adhere to the wearer's skin. This is preferable because it becomes difficult. "Not present on the rear R side" means that the position of the end T2 of all the slit parts 8 on the rear R side is biased toward the front side F from the position corresponding to the wearer's fecal excretion area. To tell.

The above-mentioned slit portion 8 can be formed by making a cut in the absorbent core 6 , or by adding a non-breathable material to the area that should become the slit portion 8 in the accumulation recess provided on the outer peripheral surface of the rotating drum. It can be manufactured by providing a convex portion.

Regarding the slit portion 8, as shown in FIG. It is preferable that the sheet 72) is bonded at the slit portion 8. That is, it is preferable that the skin side core wrap sheet 71 and the non-skin side core wrap sheet 72 enter the slit portion 8 from both sides of the absorbent core 6 and are bonded together. At this time, it is more preferable that the slit portion 8 is a through hole. It is more preferable that the above-mentioned adhesive does not peel off even if it gets wet with excretory liquid. This makes it difficult for the superabsorbent polymer 67 to move to the slit position of the absorbent body 5, and the discolored superabsorbent polymer 67 becomes difficult to see from the outside. Note that the core wrap sheets 71 and 72 can be bonded to each other by various methods that achieve the above-mentioned effects.

Next, each member constituting the diaper 10 will be explained.

(Absorber 5)
As the liquid-retaining absorbent body 5, any material used in this type of diaper can be used without particular limitation, as long as it exhibits the effects of the present invention.
It is preferable that the absorbent body 5 contains synthetic fibers. Specific examples of synthetic fibers include polypropylene fibers, polyethylene fibers, and polyester fibers. Further, it is preferable that at least the absorbent core 6 of the absorbent core 6 and the core wrap sheet 7 that constitute the absorbent core 5 contain synthetic fibers, and both the absorbent core 6 and the core wrap sheet 7 contain synthetic fibers. More preferably, it contains fibers. By containing synthetic fibers, the absorbent body 5 becomes difficult to weaken even when exposed to excretory fluid. As a result, it is possible to suppress the discolored superabsorbent polymer 67 from being visible through the gap between the deformed absorbent body 5.

In the absorbent core 6, it is preferable that the surface area of the superabsorbent polymer 67 increases toward the skin surface. When the superabsorbent polymer 67 has a large surface area, it tends to appear white due to diffuse reflection of light. Thereby, even if the superabsorbent polymer 67 near the skin side changes color, the diaper 10 tends to look white when viewed from the skin side.

Further, the absorbent body 5 may contain an antioxidant. Specific examples of antioxidants include triethylene glycol-bis-[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3, 5-di-t-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenylpropionate and 3,5-di-t-butyl-4) Examples include hindered phenolic antioxidants such as -hydroxybenzylphosphonate-diethyl ester, and amine antioxidants such as n-butylamine, triethylamine, and diethylaminomethyl methacrylate. It may be contained in either or both of the absorbent core 6 and core wrap sheet 7 that constitute the absorbent core 6 and the core wrap sheet 7. For example, it may be contained in the synthetic fibers in the absorbent body, or the hot It may be included in the melt adhesive.However, this does not include incorporating the antioxidant into the superabsorbent polymer.This eliminates the need for expensive superabsorbent polymers that contain components that suppress discoloration. Even if a general-purpose superabsorbent polymer is used, discoloration of the superabsorbent polymer is suppressed, and even if discoloration occurs, it is not noticeable from the outside of the diaper 10, in combination with the effect of the structure of the absorbent core 6 described above. It can be eliminated.

(Top sheet 3)
The topsheet 3 is liquid-permeable, and any material used in this type of diaper can be used without particular limitation. Hydrophilic thermal bond nonwoven fabrics are preferred, and air-through nonwoven fabrics are particularly preferred, from the viewpoint of allowing excreted body fluids to quickly pass through and transfer to the absorbent body, and from the standpoint of improving the feel to the skin. It is preferable that the fiber is a thermoplastic resin fiber that has been subjected to a hydrophilic treatment, and that the fiber has been subjected to three-dimensional crimp such as a secondary crimp or a tertiary crimp. Specifically, polyethylene, polypropylene, polyester, nylon, and composite fibers thereof are prepared and coated with various hydrophilic agents before being cut into predetermined lengths to form staples. Hydrophilic agents include various alkyl sulfonates represented by α-olefin sulfonates, acrylates, acrylate/acrylamide copolymers, esteramides, salts of esteramides, polyethylene glycol and its derivatives, water-soluble Hydrophilic treatment using hydrophilic agents known to those skilled in the art, such as polyester resins, various silicone derivatives, various saccharide derivatives, and mixtures thereof, can be used.

It is preferable that the top sheet 3 has an uneven structure. If the top sheet 3 with the uneven structure is arranged on the skin side of the absorber, diffuse reflection of light tends to occur on the skin side of the top sheet 3, and the diaper 10 tends to look white when viewed from the skin side. Become. As a result, the discolored superabsorbent polymer 67 becomes difficult to see from the outside.

It is preferable that the fibers constituting the topsheet 3 contain a color tone changing agent. The color tone changing agent refers to a component that has the effect of reducing the transmittance of light incident on the topsheet 3 and scattering it. By blending the color tone changing agent into the constituent fibers of the topsheet 3, the discolored superabsorbent polymer 67 becomes difficult to see from the skin side.

Specific examples of the color tone changing agent include inorganic powders and organic powders that have a different refractive index from the constituent fiber components of the topsheet 3.
Examples of the inorganic powder include titanium oxide, porous silicon oxide (silica), porous silica, aluminum oxide (alumina), lime, and clay minerals. Examples of clay minerals include smectite, montmorinite, bentonite, kaolinite, sericite, illite, gluconite, chlorite, zeolite, talc, mizucanite, and the like.
Examples of the organic powder include polyethylene powder, polyester powder, polypropylene powder, polyacrylic powder, polyacrylate powder, cellulose powder, viscose powder, silk powder, silicone compound powder, fluorine compound powder, and the like. Also included are organic powders colored with pigments. Among these, it is preferable to use titanium oxide as the color tone changing agent .
The blending amount of the color tone changing agent is preferably 0.1% by mass or more, more preferably 1% by mass or more, and even more preferably 3% by mass or more, based on 100% by mass of all the constituent fibers of the topsheet 3. By blending a certain amount or more of titanium oxide into the constituent fibers of the topsheet 3, light can be effectively scattered. On the other hand, the upper limit of the amount of titanium oxide added to the constituent fibers of the topsheet 3 is not particularly limited as long as it achieves the effects of the present invention, but 10% by mass or less is practical.

(Back sheet 4)
For the back sheet 4, a moisture-permeable film alone, a composite sheet of a film and a nonwoven fabric bonded together, or a water-repellent nonwoven fabric (SMS, SMMS, etc.) is used. From the viewpoint of cost and matching with the anti-slip adhesive, it is preferable to use the moisture-permeable film alone as the leak-preventing material. In this case, the film material may be a film made by melting and kneading a thermoplastic resin and an inorganic filler that is incompatible with the thermoplastic resin and then stretching the extruded film to a predetermined size to form micropores, or a film that is essentially water-soluble. Examples include non-porous films that have high compatibility with water vapor and allow water vapor to escape, such as permeable membranes.

It is preferable that the back sheet 4 is provided with the above-mentioned covering color. It is preferable that the position of the covering color overlaps the position in the absorbent core 6 where a large amount of the superabsorbent polymer 67 is present when the absorbent core 51 is viewed from above. In particular, if cute characters such as rabbits and cats are printed on the back sheet 4 as the wrapping color, the discoloration of the superabsorbent polymer 67 will be less noticeable from the back sheet 4 side, and at the same time, the diaper 10 will be more appealing to consumers, which is preferable. .

Further, various materials commonly used in this type of article can be used for the outer body 2, the side sheet 9, the elastic members disposed thereon, the outer nonwoven fabric 48, and the intermediate member 35 that constitute the diaper 10.

As described above, in the diaper 10 of this embodiment, the discoloration of the superabsorbent polymer 67 is difficult to see from the outside, so it maintains a good appearance even without using a superabsorbent polymer containing a component that suppresses discoloration. can.

Although the diaper 10 of this embodiment is shown as a pants-type diaper, it is not limited thereto, and may be a tape-type diaper. Further, in the diaper 10 of this embodiment, the outer case is shown as being separated into the front side and the rear side, but the outer case is not limited to this and various shapes can be adopted. For example, the exterior body may be shaped to cover the entire front side portion 10F, middle portion 10C, and rear side portion 10R of the diaper 10, and may be narrowed in the width direction at the middle portion 10C of the diaper 10. The shape of the absorbent core 6 is also not limited to that of this embodiment, and various shapes can be adopted. For example, the planar shape of the absorbent core 6 may be narrowed in the width direction X at the intermediate portion C.

The absorbent article of the present invention is a concept that includes absorbent articles such as panty liners, incontinence pads, sanitary napkins, and urine absorbing pads, in addition to the diapers of the above embodiments. Further, other members may be appropriately incorporated into the above structure according to the purpose and function.

Regarding the embodiments described above, the present invention further discloses the following absorbent article.

<1>
An absorbent article comprising an absorbent body having an absorbent core and a core wrap sheet covering the skin side and the non-skin side of the absorbent core,
On at least one of the skin side and non-skin side of the absorbent core, L ^* value: 40 or more and 100 or less, a ^* value: -12 or more and 3 or less, b ^* value in the L ^* a ^* b ^* color system. : There are members with colors in the range of -24 or more and 3 or less,
The absorbent core is an aggregate of a superabsorbent polymer and pulp fibers, and the superabsorbent polymer is arranged on the skin side of the absorbent core,
A joint between the absorbent core and the core wrap sheet is disposed on the skin side of the absorbent core , and the joint between the absorbent core and the core wrap sheet is arranged on the skin side of the absorbent core. An absorbent article, in which a room surrounding a superabsorbent polymer is arranged, and a region where the superabsorbent polymer is arranged is partitioned.

<2>
The absorbent article according to <1>, wherein the basis weight of the joint portion on the skin side of the absorbent core is 3 g/m ² or more and 10 g/m ² or less.
<3>
The absorbent article according to <1> or <2>, wherein the joint portion is arranged in a spiral shape.
<4>
The absorbent core has a longitudinal direction corresponding to a direction in which the front side, crotch, and back side of the wearer are connected, and a width direction perpendicular to the longitudinal direction,
The absorbent according to any one of <1> to <3>, wherein the rooms surrounding the superabsorbent polymer are arranged in rows in the longitudinal direction, and the rows are arranged in three or more rows in the width direction. Goods.
<5>
The absorbent article according to any one of <1> to <4>, wherein in the absorbent core, the basis weight of the superabsorbent polymer increases from the non-skin side to the skin side.
<6>
When the absorbent core is divided into a surface portion located on the skin side and a back surface portion located on the non-skin side in the thickness direction, the basis weight of the superabsorbent polymer in the surface portion is 40 g. /m ² or more, the absorbent article according to any one of <1> to <5> above.
<7>
The absorbent article according to any one of <1> to <6>, wherein a topsheet is disposed on the skin side of the absorbent body, and an intermediate member is disposed between the absorbent body and the topsheet. .
<8>
The absorbent article according to <7>, wherein the intermediate member is an achromatic color with an L ^* value expressed in the L ^* a ^* b ^* color system of 50 or more and 80 or less.
<9>
The absorbent article according to any one of <1> to <8>, wherein the L ^* value shown in the L ^* a ^* b ^* color system of the absorbent body seen from the skin side of the absorbent article is 85 or less. Absorbent articles.
<10>
The absorbent article according to any one of <1> to <9> above, wherein the absorbent body has a compression section.
<11>
<1>~, wherein the absorbent core is provided with a slit portion, and the core wrap sheets placed on the skin side and the non-skin side of the absorbent core are adhered to each other at the slit portion. The absorbent article according to any one of <10>.
<12>
The absorbent article according to any one of <1> to <11>, wherein in the absorbent core, the surface area of the superabsorbent polymer increases toward the skin surface.
<13>
A backsheet is disposed on the non-skin side of the absorber, and the backsheet has the above-mentioned L ^* a ^* b ^* color system, L ^* value: 40 or more and 100 or less, a ^* value: -12. The absorbent article according to any one of <1> to <12>, wherein the absorbent article is a member having a color in a range of from 3 to 3, b ^* value: -24 to 3.
<14>
The absorbent article according to any one of <1> to <13>, wherein a surface sheet with an uneven structure is disposed on the skin side of the absorbent body.
<15>
The absorbent article according to any one of <1> to <14>, wherein the absorbent body contains an antioxidant.

1 Absorbent body 11 Side seal part 12 Waist opening 13 Leg opening 2 Exterior body 21 Front exterior body 22 Rear exterior body 3 Top sheet 35 Intermediate member 4 Back sheet 5 Absorbent body 55 Adhesive part 56 Room 56R Space 6 Absorbency Core 61 Surface portion 62 Back portion 67 Super absorbent polymer 68 Pulp fiber 69 Outer edge of skin side of absorbent core 7 Core wrap sheet 71 Skin side core wrap sheet 72 Non-skin side core wrap sheet 75 Laminated portion of core wrap sheet 8 Slit portion 9 Side sheet 91 Elastic member 92 Three-dimensional gather portion 93 Elastic member 94 Leg gather portion 10 Diaper 10F Front side portion of diaper 10C Middle portion of diaper 10R Rear side portion of diaper 10D Waist portion of diaper F Front side portion of absorbent core C Middle part of the absorbent core R Rear part of the absorbent core Y Longitudinal direction of the absorbent core (or longitudinal direction of the absorbent main body)
X Width direction of absorbent core (or width direction of absorbent body)

Claims (6)

An absorbent article comprising an absorbent body having an absorbent core and a core wrap sheet covering the skin side and the non-skin side of the absorbent core,
A top sheet is disposed on the skin side of the absorbent body, and an intermediate member is disposed between the absorbent body and the top sheet,
At least one of the core wrap sheet and the top sheet on the skin side of the absorbent core has an L ^* value of 40 or more and 75 or less, a ^* value of -12 or more and 0 or less in the L ^* a ^* b ^* color system. , b ^* value: has a color in the range of -24 or more and -6 or less,
The absorbent core is an aggregate of a superabsorbent polymer and pulp fibers, and the superabsorbent polymer is arranged on the skin side of the absorbent core,
A joint between the absorbent core and the core wrap sheet is disposed on the skin side of the absorbent core, and the joint allows the height to be increased in at least a portion of the skin side of the absorbent core. A room surrounding the absorbent polymer is arranged, a region in which the superabsorbent polymer is arranged is divided, and a plurality of the superabsorbent polymers are arranged in the region in a planar direction,
The color is in a range of complementary colors to the color of the superabsorbent polymer after discoloration,
The intermediate member is an achromatic color with an L ^* value expressed in the L ^* a ^* b ^* color system of 50 or more and 80 or less,
An absorbent article in which at least one of the coreap sheet and the top sheet on the skin side, which has the color, the intermediate member, and the superabsorbent polymer overlap in a plan view. The absorbent core has a longitudinal direction corresponding to a direction in which the front side, crotch, and back side of the wearer are connected, and a width direction perpendicular to the longitudinal direction,
The absorbent article according to claim 1, wherein the rooms surrounding the superabsorbent polymer are arranged in rows in the longitudinal direction, and the rows are arranged in three or more rows in the width direction. The superabsorbent polymer includes those disposed on the skin side of the absorbent core as well as those blended with the pulp fibers, and in the absorbent core, from the non-skin side to the skin side. The absorbent article according to claim 1 or 2, wherein the superabsorbent polymer has a large basis weight. When the absorbent core is divided into a surface portion located on the skin side and a back surface portion located on the non-skin side in the thickness direction, the basis weight of the superabsorbent polymer in the surface portion is 40 g. The absorbent article according to any one of claims 1 to 3, wherein the absorbent article has a particle size of /m ² or more. The absorbent article according to any one of claims 1 to 4 , wherein the absorbent body has a compression section. Claims 1 to 5 , wherein the absorbent core has a slit section, and the core wrap sheets disposed on the skin side and the non-skin side of the absorbent core are adhered to each other at the slit section. The absorbent article according to any one of the above.

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