CN114040737A

CN114040737A - Absorbent article

Info

Publication number: CN114040737A
Application number: CN202080046274.8A
Authority: CN
Inventors: 松田昂平; 川口宏子
Original assignee: Kao Corp
Current assignee: Kao Corp
Priority date: 2019-06-28
Filing date: 2020-05-11
Publication date: 2022-02-11
Anticipated expiration: 2040-05-11
Also published as: JP7351657B2; JP2021007516A; WO2020261780A1; CN114040737B

Abstract

The invention provides an absorbent article having an absorbent core and a core-covering sheet covering the skin surface side and the non-skin surface side of the absorbent core, wherein the absorbent article is provided with a core-covering sheet having a surface L on at least one of the skin surface side and the non-skin surface side of the absorbent core^*a^*b^*At L in the color system^*A value of 40 to 100 a^*A value of-12 or more and 3 or less, b^*And a color component having a value in the range of-24 or more and 3 or less, wherein the absorbent core is an assembly of a super absorbent polymer and pulp fibers, the super absorbent polymer is disposed on the skin surface side of the absorbent core, a joint portion between the absorbent core and the core-covering sheet is disposed on the skin surface side of the absorbent core, a compartment in which the super absorbent polymer is surrounded by the joint portion is disposed in at least a part of the skin surface side of the absorbent core, and a region in which the super absorbent polymer is disposed is defined.

Description

Absorbent article

Technical Field

The present invention relates to an absorbent article.

Background

A Super Absorbent Polymer (SAP) used in an absorbent article such as a diaper may become yellow or brown due to oxidation in a high-temperature and high-humidity environment, and the appearance of the absorbent article may be deteriorated. Such a phenomenon is particularly likely to occur in subtropical or tropical areas such as south-east asia. Therefore, a technique has been proposed so far in which discoloration of a super absorbent polymer is suppressed by using an antioxidant or the like, and a good appearance of an absorbent article is maintained.

For example, patent document 1 describes a technique of using an acrylic acid or hydroquinone (quinhydrone) inhibitor having a small content of hydroquinone, patent document 2 describes a technique of using a reducing compound and a specific acid (salt), and patent document 3 describes a technique of using a sulfinic acid derivative.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 11-322846

Patent document 2: japanese patent laid-open publication No. 2003-52742

Patent document 3: japanese Kokai publication 2006-521431

Disclosure of Invention

Technical problem to be solved by the invention

The invention provides an absorptive article having an absorber having an absorptive core and a core-covering sheet covering the skin surface side and the non-skin surface side of the absorptive core, wherein at least one of the skin surface side and the non-skin surface side of the absorptive core is provided with a core-covering sheet having a L-shaped cross section^*a^*b^*At L in the color system^*A value of 40 to 100 a^*A value of-12 or more and 3 or less, b^*And a color component having a value in the range of-24 or more and 3 or less, wherein the absorbent core is an assembly of a super absorbent polymer and pulp fibers, the super absorbent polymer is disposed on the skin surface side of the absorbent core, a joint portion between the absorbent core and the core-covering sheet is disposed on the skin surface side of the absorbent core, a compartment in which the super absorbent polymer is surrounded by the joint portion is disposed in at least a part of the skin surface side of the absorbent core, and a region in which the super absorbent polymer is disposed is defined.

The above and other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings.

Drawings

Fig. 1 is a perspective view showing a diaper according to a preferred embodiment of the absorbent article of the present invention.

Fig. 2 is a partially cut-away developed plan view schematically showing the diaper shown in fig. 1 in a state seen from the skin surface side when the diaper is developed and stretched after the side seals are cut off.

Fig. 3 is a sectional view III-III of fig. 2.

Fig. 4 is a partially enlarged plan view schematically showing the arrangement state of the compartments formed at the joint portions and the super absorbent polymer on the skin surface side of the absorbent core.

In fig. 5, (a) is a partially enlarged sectional view showing a state in which the absorbent core is laminated with a member on the skin surface side and a member on the non-skin surface side of the absorbent core, and (B) is a partially enlarged sectional view showing a modification of the view (a).

Fig. 6 is a plan view showing a state in which a slit portion is arranged in the absorbent core.

Fig. 7 is a sectional view in the thickness direction of the absorbent core schematically showing a state where the core-covering sheets arranged on the skin surface side and the non-skin surface side of the absorbent core are joined to each other at the slit portion.

Detailed Description

The present invention relates to an absorbent article capable of maintaining a good appearance without using a super absorbent polymer containing a component for inhibiting discoloration.

In the techniques described in patent documents 1 to 3, an expensive super absorbent polymer containing a component for inhibiting discoloration such as an antioxidant has to be used, and the price of the absorbent article is increased.

In contrast, the absorbent article of the present invention can maintain a good appearance.

Hereinafter, a diaper which is a preferred embodiment of the absorbent article of the present invention will be described with reference to the drawings.

In the present invention, in a worn state of the absorbent article, a side in contact with the skin of a wearer is referred to as a skin surface side, a skin contact surface side, or a front surface side, and a side opposite thereto is referred to as a non-skin surface side, a non-skin contact surface side, or a back surface side. These terms are used as terms indicating relative positional relationships among component structures of an absorbent article, even with respect to components that do not have a surface that contacts the skin of a wearer in a worn state of the absorbent article. The normal direction to the front or back of the absorbent article is referred to as the thickness direction.

As shown in fig. 1, the diaper 10 of the present embodiment includes an absorbent main body 1 and an outer package 2. The exterior body 2 has a front side exterior portion 21 and a rear side exterior body 22 corresponding to the front side and the rear side of the wearer, respectively. The front side refers to the ventral side of the wearer and the back side refers to the back side of the wearer. The front outer cover 21 and the rear outer cover 22 are laterally long, and both side edges thereof overlap and are joined to the side seals 11 to form an annular waistline portion 10D of the diaper 10. The portion of the absorbent main body 1 extending from the outer package 2 forms the middle portion 10C of the diaper 10. The diaper 10 has a waist opening 12 opened above the waist portion 10D and a pair of

leg openings

13, 13 opened on both left and right sides of the intermediate portion 10C.

Fig. 2 shows the diaper 10 in an unfolded state with the

side seals

11, 11 broken. Here, the unfolded state means a state in which each part is extended to expand the absorbent article into a flat shape.

The diaper 10 is divided into front side portions 10F, an intermediate portion 10C, and rear side portions 10R in an unfolded state. The front side outer cover 21 and the rear side outer cover 22, which are laterally long, are disposed in the front side portion 10F and the rear side portion 10R, respectively. The vertically long absorbent main body 1 is disposed so that the longitudinal direction thereof faces the front side portion 10F, the intermediate portion 10C, and the rear side portion 10R of the diaper 10. In this arrangement, the absorbent main body 1 has a longitudinal direction Y corresponding to a direction in which the front side, crotch portion, and rear side of the wearer are continuous, and a width direction X orthogonal to the longitudinal direction Y.

As shown in fig. 3, the absorbent body 1 constituting the diaper 10 has a liquid-permeable front sheet 3 on the skin surface side, a leakproof back sheet 4 on the non-skin surface side, and a liquid-retentive absorbent body 5 disposed between the front sheet 3 and the back sheet 4. The absorbent body 5 has: an absorbent core 6 composed of an aggregate of a super absorbent polymer 67 and pulp fibers 68; and a core-spun sheet 7 covering the outer periphery of the absorbent core 6. The core sheet 7 is made of a hydrophilic material, for example, hydrophilic paper or nonwoven fabric.

In the present embodiment, the pair of side sheets 9 is provided on both sides of the absorbent main body 1 in the longitudinal direction Y. An elastic member 91 formed in an extended state is disposed at an inner end of the side sheet 9 in the width direction X to form a three-dimensional gather portion 92. Further, an elastic member 93 formed in an extended state is disposed at an outer end portion in the width direction X of the side sheet 9 to form a leg gather 94. In the absorbent body 1 of the present embodiment, the outer-covering nonwoven fabric 48 is disposed on the non-skin surface 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 orthogonal to the longitudinal direction, similarly to the absorbent main body 1. As shown in fig. 2 and 3, the core sheet 7 covers the entire length direction Y of the absorbent core 6 and extends in the width direction X, covering the skin surface side, both sides, and the non-skin surface side (outer periphery) of the absorbent core 6. Specifically, the skin-side wrapping sheet 71 covers the skin side of the absorbent core 6, and the non-skin-side wrapping sheet 72 covers the non-skin side of the absorbent core 6. The non-skin-side core sheet 72 further extends in the width direction X, is rolled up to both side portions and the skin surface side, and is laminated and joined to the skin surface side at both end portions in the width direction X of the skin-side core sheet 71. The laminated portion is a laminated portion 75 extending over the entire length of the absorbent core 6 in the longitudinal direction Y at 2 positions at both ends of the absorbent core 6 in the width direction X. In fig. 3, 2 laminated sections 75 of the core sheet 7 are arranged on the skin surface side of the absorbent core 6, but the present invention is not limited thereto. For example, the number of the cells may be 1, 3 or more on the non-skin surface side or the skin surface side. When 1 sheet is disposed on the non-skin surface side of the absorbent core 6, the laminate 75 may be formed by, for example, rolling 1 core sheet from the skin surface side of the absorbent core 6 to both side portions and the non-skin surface side and laminating the end portions. In this case, of the 1 core sheet, a portion disposed on the skin surface side of the absorbent core 6 is referred to as a skin surface side core sheet 71, and a portion disposed on the non-skin surface side of the absorbent core 6 is referred to as a non-skin surface side core sheet 72.

As shown in fig. 3, a super absorbent polymer 67 is disposed on the skin surface side of the absorbent core 6. The super absorbent polymer 67 is divided into compartments on the skin surface side of the absorbent core 6 by the joining portions 55 described later. The super absorbent polymer 67 is preferably uniformly disposed on the skin surface side of the absorbent core 67. The term "uniform" as used herein means that the amount of the super absorbent polymer 67 falling off the skin surface of the absorbent core 6 is measured for each section by the following method, and the ratio of the difference between the amount of each section and the average amount of all sections to the average amount of all sections is within ± 100% in terms of gram weight ratio. The ratio of the amount of each partition to the average amount of each partition is preferably within ± 50%, more preferably within ± 30%, in terms of a gram weight ratio.

(method of measuring distribution of super absorbent Polymer 67 in skin surface side of absorbent core 6)

(1) The absorbent article including the absorbent body is divided into 2 sections in the lateral direction and 3 sections in the longitudinal direction in a plan view.

(2) The absorbent core was exposed by cutting the skin contact surface side (e.g., the core-covering sheet and the topsheet) from the absorbent core located on the skin surface side of 1 section. The exposed portion was shaken downward 20 times, and the mass of the detached super absorbent polymer was measured and converted into a gram weight (g/m)²). This eliminates the influence of the presence or absence of a slit or the difference in area due to the shape (for example, hourglass shape) of the absorbent core, and makes it possible to compare the amounts of superabsorbent polymer dropped out in the respective sections.

(3) The process (2) is performed for each partition. Next, an average slip-off amount (gram weight conversion) of all the segments is calculated from the measurement values of the segments, and a ratio of a difference between the slip-off amount (gram weight conversion) of each segment and the average slip-off amount (gram weight conversion) in all the segments to the average slip-off amount (gram weight conversion) is calculated. That is, the "amount of shedding of each partition-the average amount of shedding of all partitions ]/[ the average amount of shedding of all partitions" is calculated.

The super absorbent polymer 67 may be disposed not only on the skin surface side of the absorbent core 6 but also on the inside of the super absorbent polymer 67. Inside, the super absorbent polymer 67 is preferably dispersed in the thickness direction and the plane direction of the absorbent core 6, and is supported between the fibers of the pulp fibers 68.

As shown in fig. 3 and 4, a joint 55 between the absorbent core 6 and the core sheet 7 (skin-side core sheet 71) is disposed on the skin surface side of the absorbent core 6. The bonding portion 55 is formed by applying a bonding agent. As the adhesive, those generally used for such articles can be used, and examples thereof include a hot-melt adhesive. The adhesive can be applied by a method generally used for such articles. For example, spray coating, gravure coating, or the like can be exemplified. In order to maintain the liquid absorbency and the uniform arrangement of the super absorbent polymer 67, the adhesive is preferably applied linearly and intermittently to the skin surface of the absorbent core 6, more preferably spirally. That is, the bonding portions 55 formed by the bonding agent are preferably linearly spaced from the skin surface of the absorbent core 6, and are preferably spirally disposed.

As shown in fig. 3 and 4, a compartment 56 surrounding a super absorbent polymer 67 is disposed at least in a part of the skin surface side of the absorbent core 6 by a joint 55. That is, the joint portions 55 serve as separation columns for separating the arrangement regions of the super absorbent polymer 67 on the skin surface side of the absorbent core 6.

The compartment 56 has a space 56R vertically sandwiched between the skin surface of the absorbent core 6 and the core sheet 7 (skin surface side core sheet 71) in a region surrounded by the joint portion 55. In the space 56R provided in the compartment 56, a plurality of super absorbent polymers 67 are uniformly arranged in the planar direction. A plurality of the compartments 56 are disposed on the skin surface of the absorbent core 6. Thereby, the arrangement region of the super absorbent polymer 67 is partitioned on the skin surface side of the absorbent core 6.

The movement of the super absorbent polymer 67 disposed on the skin surface side of the absorbent core 6 can be suppressed well by the above-described compartment 56. That is, the joint portion 55 is formed as a partition column, and the super absorbent polymer 67 is not easily moved between the

partitioned compartments

56, 56. Generally, the diaper 10 is folded after manufacture, is stored in a package for sale in a compressed state, is then transported and sold, and is subjected to various external forces in various situations such as opening after purchase and use. In this case, by the arrangement of the compartments 56 formed by the joint portions 55, the movement of the super absorbent polymer 67 is suppressed, and the uniformity of the super absorbent polymer arranged on the skin surface side of the absorbent core 6 is easily maintained.

Thereby, even if the super absorbent polymer 67 is discolored, blocking of the discolored color (for example, yellow or brown) can be suppressed. Further, the super absorbent polymer 67 is uniform without forming a lump on the skin surface side of the absorbent core 6, thereby enabling quick absorption of the excretory fluid and good penetration of the excretory fluid from the skin surface side into the absorbent core 6. This improves the absorption performance of the entire absorbent core 6.

As described above, a plurality of such compartments 56 are disposed on at least a part of the skin surface side of the absorbent core 6. The region where the plurality of compartments 56 are arranged is preferably within the range of 1/3 of the absorbent body, more preferably within the range of 3/4 of the absorbent body, and still more preferably within the entire region of the skin surface side of the absorbent core 6, from the viewpoint of maintaining a uniform arrangement of the super absorbent polymer 67, making the color (e.g., yellow or brown) after discoloration inconspicuous, and achieving high liquid absorbency. The absorbent material preferably includes a liquid receiving region, which will be described later, in the range of 1/3 and in the range of 3/4.

The compartments 56 are preferably arranged in rows in the longitudinal direction Y of the absorbent core 6, and the rows are preferably arranged in 3 or more rows in the width direction X. This can effectively suppress the movement, the bias, and the falling off of the super absorbent polymer 67 in the width direction X, and can maintain the uniform arrangement. From such a viewpoint, the rows are more preferably arranged in 4 rows or more, and still more preferably in 5 rows or more in the width direction X. In addition, from the viewpoint of not impairing the absorption performance, the rows are preferably arranged in the width direction X in 10 rows or less, more preferably in 8 rows or less, and still more preferably in 6 rows or less. Specifically, the rows are preferably arranged in the width direction X in 3 rows or more and 10 rows or less, more preferably in 4 rows or more and 8 rows or less, and still more preferably in 5 rows or more and 6 rows or less.

The number of the cells 56 in 1 row (the number in the longitudinal direction Y) is preferably 5 or more, more preferably 10 or more, and even more preferably 20 or more, from the viewpoint of effectively suppressing the migration, the bias, and the falling-off of the super absorbent polymer 67 in the longitudinal direction Y and maintaining the uniform arrangement. The number of the compartments 56 in 1 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 the absorption performance. Specifically, the number of the compartments 56 (the number in the longitudinal direction Y) in 1 row is preferably 5 or more and 100 or less, more preferably 10 or more and 50 or less, and still more preferably 20 or more and 30 or less.

The above-described compartment 56 has a planar shape whose edge is formed by the linear joining portion 55, and the planar shape can be formed into various shapes. Examples thereof include a circle, an ellipse, a polygon, and the like. In particular, the planar shape of the compartments 56 is preferably circular or elliptical from the viewpoint of keeping the uniform arrangement of the super absorbent polymer 67, suppressing the movement between the

compartments

56, 56 of the super absorbent polymer 67, and preventing gel blocking from being easily generated on the skin surface side of the absorbent core 6 at the time of liquid absorption. From this viewpoint, the joint portion 55 is preferably arranged in a spiral shape. By disposing the joining portions 55 in a spiral shape, the circular or elliptical compartments 56 can be disposed without a gap, and uniform disposition of the super absorbent polymer 67 can be efficiently achieved.

The line width of the linear joining portion 55 is preferably 5mm or less, more preferably 3mm or less, and still more preferably 1mm or less, from the viewpoint of maintaining the liquid absorbability of the absorbent core 6 and the uniform arrangement of the super absorbent polymer 67. The line width of the linear joint portion 55 is preferably 0.1mm or more, more preferably 0.3mm or more, and even more preferably 0.5 or more, from the viewpoint of suppressing the movement between the

compartments

56, 56 of the super absorbent polymer 67. Specifically, the line width of the linear bonding portion 55 is preferably 0.1 to 5mm, more preferably 0.3 to 3mm, and still more preferably 0.5 to 1 mm.

Further, from the viewpoint of suppressing the dropping of the super absorbent polymer 67 and maintaining the uniform arrangement of the super absorbent polymer 67 when the diaper 10 is used, it is preferable that the joining portion 55 constituting the above-mentioned partition 56 is also arranged at the outer edge 69 of the skin surface of the absorbent core 6 (see fig. 3 and 6). The "outer edge 69 on the skin surface of the absorbent core 6" referred to herein is an edge portion along the outer periphery of the absorbent core 6 when the absorbent core 6 is viewed in a plan view from the skin surface side. In this case, the engaging portion 55 is preferably present at least in a part of the outer edge 69. For example, the ratio of the joint 55 disposed over the entire 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 more preferably 50% or more. The larger the above ratio, the better. Specifically, the ratio is preferably 5% or more and 100% or less, preferably 20% or more and 100% or less, and more preferably 50% or more and 100% or less.

The grammage of the joint 55 on the skin surface side of the absorbent core 6 (the grammage of the adhesive forming the joint 55) is preferably 20g/m from the viewpoint of maintaining the liquid absorbency of the absorbent core 6 and the uniform arrangement of the super absorbent polymer 67²Hereinafter, more preferably 15g/m²Hereinafter, it is more preferably 10g/m²The following. The grammage of the skin-side joint portion 55 of the absorbent core 6 is preferably 1g/m from the viewpoint of ensuring the joint strength between the absorbent core 6 and the skin-side core sheet 71 and suppressing the movement between the

compartments

56, 56 of the super absorbent polymer 67²Above, more preferably 3g/m²Above, more preferably 5g/m²The above. Specifically, the grammage of the joint 55 on the skin surface side of the absorbent core 6 is preferably 1g/m²Above and 20g/m²Hereinafter, it is more preferably 3g/m²Above and 15g/m²Hereinafter, it is more preferably 5g/m²Above and 10g/m²The following.

(method of measuring grammage of joint 55 on skin surface side of absorbent core 6)

The area of the adhesive applied portion (portion where the adhesive portion 55 is disposed) on the non-skin surface side of the core sheet 7 and the skin surface side of the absorbent core 6 is cut out from the skin surface side of the core sheet 7 by a predetermined thickness (thickness impregnated with the adhesive, for example, 5 mm), and the pulp fibers and the super absorbent polymer are removed. The adhesive (e.g., hot melt adhesive) is extracted from the coating section using a solvent, the extracted solution is dried and cured under reduced pressure using a rotary evaporator, and the mass of the obtained adhesive is measured.

The grammage of the bonded portion 55 on the skin surface side of the absorbent core 6 was calculated by dividing the measured mass of the adhesive by the area of the portion having the width direction end and the length direction end of the application portion as the ends.

The solvent may be appropriately selected according to the kind of the binder. When the adhesive to be measured is, for example, a hot-melt adhesive, examples of the solvent include toluene, methyl ethyl ketone, and heptane.

The grammage of the super absorbent polymer 67 disposed on the skin surface side of the absorbent core 6 is preferably 10g/m from the viewpoint of maintaining the liquid absorbency of the absorbent core 6 and from the viewpoint of making the color after discoloration inconspicuous²Above, more preferably 20g/m²Above, more preferably 30g/m²The above. The grammage of the super absorbent polymer disposed on the skin surface side of the absorbent core 6 is preferably 100g/m from the viewpoint of maintaining the liquid permeability into the absorbent core 6 and suppressing the occurrence of gel blocking²Hereinafter, more preferably 80g/m²Hereinafter, more preferably 60g/m²The following. Specifically, the grammage of the super absorbent polymer disposed on the skin surface side of the absorbent core 6 is preferably 10g/m²Above and 100g/m²Hereinafter, more preferably 20g/m²Above and 80g/m²Hereinafter, more preferably 30g/m²Above and 60g/m²The following.

Further, in the diaper 10, the absorbent core 6 is disposed on at least one of the skin surface side and the non-skin surface side so as to have a L-plane^*a^*b^*L in color system^*The value: 40 to 100 a, a^*The value: 12 or more and 3 or less, b^*The value: -a component of a color in the range of 24 or more and 3 or less. The color is L^*a^*b^*Preference in color System for L^*The value: 60 to 80, a^*The value: -9 or more and 0 or less, b^*The value: -15 or more and-6 or less, more preferably L^*The value: 65 to 75 inclusive, a^*The value: -6 or more and-3 or less, b^*The value: -12 or more and-9 or less. In the present specification, the color is also referred to as a "cover color" because it is present in a member that is overlapped from above on the skin surface side or the non-skin surface side with respect to the arrangement position of the super absorbent polymer 67. Furthermore, L^*a^*b^*Color system is defined in JIS-Z-8729, L^*Indicates lightness, a^*And b^*Indicating the direction of the color. The values are represented as values from positive to negative. L is^*Larger values of (a) indicate brighter. In respect of a^*Positive values indicate a reddish orientation and negative values indicate a greenish orientation. In relation to b^*Positive values indicate a yellowish direction and negative values indicate a bluish direction.

The cover color is a color in a range complementary to the color (for example, yellow or brown) of the superabsorbent polymer 67 after the color change. The colors in complementary color relationship appear to overlap each other when the diaper 20 is viewed from the outside. I.e. appears to be a mixed color. As a result, the degree of color saturation of the discolored superabsorbent polymer 67 decreases from the outside of the diaper 10, particularly from the skin surface side, and becomes inconspicuous. More specifically, in the overlapping of the members that easily transmit light, such as the member of the fiber material such as the nonwoven fabric, the member of the filler, and the like, the color of the super absorbent polymer 67 after the color change is also projected to the covering color on the outer side than the color. As a result, the colors in a complementary color relationship are mixed with each other when viewed from the outside of the diaper 10, and the chroma of the color after the discoloration of the super absorbent polymer 67 is reduced and becomes inconspicuous.

Further, the super absorbent polymer 67 on the skin surface side of the absorbent core 6 is uniformly arranged in the planar direction, and thus the color after discoloration does not lump and appears to be dispersed in the above covering color. Therefore, when the diaper 10 is viewed from the outside, particularly from the skin side, it is possible to avoid that the colors in the complementary color relationship are respectively lumped and appear adjacent to each other. In general, if colors in a complementary color relationship are adjacent to each other in blocks, the chroma is emphasized, and the arrangement as described above can avoid the chroma of the complementary colors from being emphasized. From this viewpoint, the super absorbent polymer 67 is preferably uniformly arranged as described above.

Further, since there is a member having the covering color, it is preferable that the appearance is good from the initial stage of use of the diaper 10 regardless of the presence or absence of discoloration or the degree of discoloration of the super absorbent polymer 67.

(L in covering color)^*a^*b^*Method for measuring values of a color system

The measurement is performed by taking out the member to be measured from the absorbent article. Specifically, the adhesive or the like used for bonding the member to be measured and another member is weakened by a cooling method such as cold spraying, and then the member to be measured is carefully peeled and taken out.

The measurement was carried out by laying a white sheet on the lower side and using a color difference meter such as a simple spectrocolorimeter NF333 (trade name) manufactured by Nippon Denshoku industries Co., Ltd. In the measuring method based on the simple spectrocolorimeter NF333, the simple spectrocolorimeter is installed in a Stapler (Stapler) type

The ND110 sensor of (2) was measured at a viewing angle of 2 ° using an O-ring (small) and a light source C/2 at the tip of the sensor.

In the measurement, the sensor portion of the colorimeter is directly brought into contact with the measurement portion of the member to be measured.

As a member having a skin side with a cover color, as shown in fig. 5 (a), a front sheet 3 and a skin side core sheet 71 can be exemplified. Further, as shown in fig. 2 and 3, a side sheet 9 partially overlapped with respect to the absorbent core 6 is also included. As shown in fig. 5 (B), when the intermediate member 35 is present between the topsheet 3 and the absorbent body 5, the intermediate member 35 is also included. The intermediate member 35 is preferably made of a hydrophilic fibrous material having a function of diffusing the excretory fluid that has permeated from the topsheet 3 in the planar direction and rapidly absorbing the excretory fluid over a wide area of the absorbent body 5.

Examples of the member on which the non-skin-side covering sheet of the covering color is disposed include the back sheet 4, the non-skin-side core sheet 72, and the outer-covering nonwoven fabric 48. As shown in fig. 1 and 2, the exterior body 2 is also included in a member other than the skin surface side.

The cover color may be disposed on one of the skin-side and non-skin-side members, or may be disposed on 2 or more members. When the cover color is disposed in 2 or more members, the above-described visual effect is more preferable. For example, it is preferable that the cover color is provided in 1 member or 2 or more members on both the skin surface side and the non-skin surface side.

The color (L) obtained by making the covering color easily react with the discoloration of the super absorbent polymer 67^*a^*b^*Values of color system) and from the viewpoint of making the above-described visual effect more effective, it is preferable to dispose a cover color on a member as close as possible to the super absorbent polymer 67. For example, the skin-side core sheet 71, the intermediate member 35, the front sheet 3, and the side sheet 9 are given priority to disposing the cover color on the skin surface side. The order of priority for disposing the cover color on the non-skin surface side is the order of the non-skin surface side core sheet 72, the back sheet 4, the outer cover nonwoven fabric 48, and the outer cover 2. It is preferable that at least the covering sheet 7 is provided with a covering color on both the skin surface side and the non-skin surface side. In particular, it is preferable that the cover color is provided at least in the skin-side covering sheet 71.

The cover color may be disposed in the entire part of the member or may be disposed in a part of the member. When disposed at a portion, the configuration preferably includes a region overlapping the absorbent core 6. In consideration of accidental detachment of the super absorbent polymer 67, it is preferable that the cover color be disposed on the entire member.

When the intermediate member 35 is present as a member on the skin surface side of the absorbent core 6, the cover color may be disposed on the intermediate member 35 or may not be disposed. When not arranged, the cover color is arranged on the other skin surface side member (for example, the core sheet). Even when the intermediate member 35 is not covered with the color, the color of the super absorbent polymer 67 after the color change can be separated from the skin surface side of the diaper 10. This further reduces the saturation of the color of the super absorbent polymer 67 after discoloration, which is seen from the outside (skin surface side) of the diaper 10, in conjunction with the above-described action of the covering color of the other member, thereby further improving the effect of making it unnoticeable.

When the cover color is not provided in the intermediate member 35, L is preferably provided^*An achromatic color having a value of 50 to 80 inclusive, i.e., gray. This makes it possible to make the color of the super absorbent polymer 67 more inconspicuous after discoloration. Generally, the color saturation can be reduced by superimposing gray, and the color-changed portion can be made more inconspicuous by superimposing the color-changed portion of the polymer on the cover color and superimposing gray on the portion where the color saturation is reduced.

As described above, in the diaper 10, the super absorbent polymer 67 is disposed on the skin surface side of the absorbent core 6, and a member having the above-described cover color is disposed. In the state before use of the diaper 10, the L of the absorbent body 5 as viewed from the skin surface side of the diaper 10 is preferably set to be L^*The value is 85 or less, more preferably 80 or less, and still more preferably 75 or less. Thus, the appearance of the polymer before and after discoloration is not easily impaired. L as viewed from the skin side of the diaper 10^*The value is preferably 60 or more, more preferably 65 or more, and further preferably 70 or more. This can ensure an effect of preventing the appearance of the polymer before and after discoloration from being impaired, and can suppress the appearance from turning black before use. Specifically, in the state before use of the diaper 10, L viewed from the skin surface side of the diaper 10 is preferable^*The value is 60 or more and 85 or less, more preferably 65 or more and 80 or less, and still more preferably 70 or more and 75 or less.

L is a value viewed from the skin-side of the diaper 10^*The value can be measured, for example, by a simple spectrocolorimeter NF333 (trade name) manufactured by Nippon Denshoku industries Ltd.

In the diaper 10, it is preferable that the absorbent core 6 has a larger grammage of the super absorbent polymer 67 as it goes from the non-skin surface side to the skin surface side. The super absorbent polymer 67 includes a polymer mixed with the pulp fibers 68 in the absorbent core 6 and a polymer disposed on the skin surface side of the absorbent core 6.

The term "increased" means that the superabsorbent polymer 67 is contained in a relatively larger amount in the layer closer to the skin surface side than in the layer closer to the non-skin surface side when the absorbent core 6 is viewed in the thickness direction, and the amount is expressed by the grammage. The bias of the super absorbent polymer 67 may be gradually increased from the non-skin surface side to the skin surface side, or may be increased stepwise. The super absorbent polymer 67 is preferably contained in a larger amount in at least the outermost layer on the non-skin surface side of the absorbent core 6 than in the outermost layer on the skin surface side. This ensures high absorption capacity of the diaper 10, and also achieves rapid absorption and improved leakage prevention, together with the superabsorbent polymer 67 disposed on the skin surface side of the absorbent core 6.

From the same viewpoint, it is more preferable that the super absorbent polymer 67 is contained in the absorbent core 6 as described below. That is, as shown in fig. 3, the absorbent core 6 is first divided in the thickness direction into a front surface portion 61 located on the skin surface side and a back surface portion 62 located on the non-skin surface side. This division is performed by equally dividing the absorbent core 51 in the thickness direction by 2. In this case, the grammage of the super absorbent polymer 67 in the front face portion 61 is preferably 40g/m²Above, more preferably 60g/m²Above, more preferably 80g/m²The above. Further, the grammage of the super absorbent polymer 67 in the front surface portion 61 is preferably 250g/m from the viewpoint of preventing gel blocking due to an increase in polymer density²Hereinafter, more preferably 200g/m²Hereinafter, it is more preferably 150g/m²The following. Specifically, the grammage of the super absorbent polymer 67 in the front face portion 61 is preferably 40g/m²Above and 250g/m²Hereinafter, more preferably 60g/m²Above and 200g/m²Hereinafter, more preferably 80g/m²Above and 150g/m²The following.

(method of measuring grammage of super absorbent polymer 67 in absorbent core 6)

First, a section of a measurement target portion of the absorbent core 6 was observed with a microscope, equally divided in the thickness direction by 2, and the front surface portion 61 and the back surface portion 62 were collected.

Regarding each portion to be collected, the mass of the super absorbent polymer 67 was calculated by quantifying the mixture of the super absorbent polymer 67 and the pulp fibers 68 based on the method for quantifying the fiber and/or the water-absorbent polymer described in patent publication No. 4225821.

Specifically, the mass of each collected part was measured, and then the superabsorbent polymer 67 was reduced in molecular weight in each part. The high-absorbing polymer 67 can be reduced in molecular weight by ultraviolet irradiation. At this time, the mixture of the super absorbent polymer 67 and the pulp fibers 68 collected for each site is immersed in an aqueous solution containing ascorbic acid and riboflavin in a state where the mixture is put in a mesh bag or the like. After swelling the super absorbent polymer by immersion, the mesh bag was taken out from the aqueous solution and irradiated with the ultraviolet ray, thereby reducing the molecular weight of the super absorbent polymer 67. Subsequently, the components generated by the low molecular weight conversion are removed by washing with water. After the removed mesh bag was sufficiently washed with water, dehydration and drying were performed and the mass was measured. The mass of the pulp fiber 68 is calculated by subtracting the mass of the pocket unit from the measured mass, and the mass of the pulp fiber 68 is subtracted from the mass of each portion measured initially to obtain the mass of the super absorbent polymer 67. The grammage of the super absorbent polymer 67 for each portion was obtained based on the obtained value divided by the area of each portion. The grammage of the super absorbent polymer 67 in each of the front surface portion 61 and the back surface portion 62 was determined as an average value obtained by performing the above measurement 3 times.

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 the color change is conspicuous (for example, an end portion of the absorbent core 6).

In the compression section, the pulp fibers 68 are compressed, whereby the movement of the super absorbent polymer 67 is easily restrained. As long as this function is achieved, the depth of the compressed portion can be set appropriately, and may be the depth reaching the back surface portion 62 of the absorbent core 6. From the viewpoint of preventing the absorption of the super absorbent polymer 67 from being hindered by compression, it is preferable to form a compressed portion on the skin surface side of the absorbent core 5, the compressed portion being formed to a depth of the front portion 61 of the absorbent core 6. The compressed portion is preferably located only on the front surface portion 61, from the viewpoint of not reducing the flexibility of the absorbent core 6. The compressed portion can be formed in a linear shape in the planar direction of the absorbent core 5 on the skin surface side with respect to the absorbent core 5 including the absorbent core 6 and the core sheet 7, for example. The linear compressing portion may be arranged in a lattice shape inclined with respect to the longitudinal direction Y and the width direction X, for example. The shape of the compressed portion is not particularly limited as long as the above-described function can be achieved, and examples thereof include a staggered shape and a wavy shape, in addition to the above-described oblique lattice shape. The compressing portion is not limited to being provided only in the absorbent body 5, and may be configured to compress the absorbent body 5 and the topsheet 3 integrally, for example.

In the diaper 10, as shown in fig. 6, the absorbent core 6 is preferably provided with a slit 8. The slit 8 is a space formed in the absorbent core 6 in the thickness direction from the skin surface side, in which the amount of pulp is smaller than that in the periphery. The slit portion 8 may be a slit-shaped portion or a groove having a predetermined width. In the arrangement position of the slit portion 8, the excretory fluid easily permeates in the thickness direction of the absorbent core 6. This can improve the rapid liquid absorption and retention properties and the moisture regain resistance of the diaper 10. That is, the above-mentioned rapid improvement of the liquid absorption retention property and the moisture regain resistance and the inconspicuous discoloration of the super absorbent polymer 67 can be simultaneously achieved.

The slit portion 8 preferably has a depth from the skin surface side of the absorbent core 6 to the back surface portion 62, and more preferably has a through hole from the skin surface side to the non-skin surface side of the absorbent core 6, from the viewpoint of improving the liquid absorption retention property and the moisture regain resistance. The slit 8 is preferably located in the liquid receiving region Q of the absorbent core 6 from the same viewpoint as described above.

The "liquid receiving region Q" referred to herein is a region that directly receives excretory fluid such as urine. In the diaper 10, the liquid receiving region Q is a region within 3.5cm in the left-right widthwise direction from a line S1 bisecting the length 2 in the widthwise direction X, and is a region within 8cm in the front-side direction from a line M1 bisecting the length 2 in the lengthwise direction Y. In the case where the absorbent article of the present invention is a sanitary napkin for daily use, the liquid receiving region Q is a region within 2.5cm in the lateral width direction from a line which bisects the absorbent core 6 by 3 in the longitudinal direction Y and bisects the length X of the central portion by 2 in the lateral width direction X. In the case where the absorbent article of the present invention is a sanitary napkin having a wide rear flap covering buttocks for night use or the like, the liquid-receiving region Q is a region within 2.5cm in the right-left width direction from a line bisecting 4 times in the longitudinal direction Y and 2 times in the width direction X of the second portion. When the absorbent article of the present invention is a urine collection pad or an incontinence pad, the configuration is the same as that of the diaper 10.

In fig. 6, the slit portion 8 has a length extending from the liquid receiving region Q to the front and rear in the longitudinal direction Y, and 3 slit portions are provided side by side in the width direction X. The arrangement and number of the slits 8 are not limited to this, and the embodiment shown in fig. 6 is preferable from the viewpoint of improving the liquid absorption and retention properties and the moisture regain resistance.

When there are a plurality of slit portions 8, the widths (the groove widths and the lengths in the width direction X) of the slit portions 8 may be the same or different from each other. When the width of each slit part 8 is the same, the excretory fluid is easily and uniformly and rapidly diffused in the absorbent core 6. This is preferable because a wider area of the absorbent core 6 can be sufficiently used for liquid absorption. From the viewpoint of making this effect more remarkable, the width of each slit portion 8 is preferably 1mm or more, and more preferably 3mm or more. The width of each slit portion 8 is preferably 20mm or less, and more preferably 15mm or less. Specifically, the width of each slit portion 8 is preferably 1mm or more and 20mm or less, and more preferably 3mm or more and 15mm or less. Even when the widths of the slit portions 8 are different from each other, the widths of the slit portions 8 are preferably within the above range.

When there are a plurality of slit parts 8, the lengths (lengths in the longitudinal direction Y) of the slit parts 8 may be the same or different from each other. When the length of each slit portion 8 is the same, the excretory fluid is easily and uniformly and rapidly diffused in the absorbent core 6. This is preferable because a wider area of the absorbent core 6 can be sufficiently used for liquid absorption. From the viewpoint of making this effect more remarkable, the length of each slit portion 8 is preferably 50mm or more, and more preferably 100mm or more. The length of each slit portion 8 is preferably 350mm or less, and more preferably 300mm or less. Specifically, the length of each slit portion 8 is preferably 50mm or more and 350mm or less, and more preferably 100mm or more and 300mm or less. Even when the lengths of the slits 8 are different from each other, the length of each slit 8 is preferably within the above range.

The length of each slit portion 8 is preferably formed as follows when the absorbent core 6 is divided into a front portion F, an intermediate portion C, and a rear portion R by 3 equal divisions in the longitudinal direction Y.

When the lengths of the respective slit portions 8 are the same, the positions of the front F side end portions T1 of the slit portions 8 may be the same or different from each other. Similarly, the positions of the end portions T2 on the rear portion R side of the respective slit portions 8 may be the same as each other, or may be different from each other. In fig. 6, the positions of the end T1 on the front F side of each slit part 8 are the same, and the positions of the end T2 on the rear R side of each slit part 8 are the same.

Preferably, each slit portion 8 does not exist in the rear portion R. This makes it possible to balance the liquid absorption capacity of the absorbent core 6, the liquid diffusibility in the absorbent core 6, and the favorable wearing feeling of the diaper 10. In particular, the distance between the end T2 on the rear portion R side of each slit portion 8 and the boundary position T3 between the intermediate portion C and the rear portion R in the absorbent core 6 is preferably 5mm or more, more preferably 10mm or more, and preferably 50mm or less, more preferably 45mm or less. Specifically, the distance between the boundary position T3 and the end T2 on the rear portion R side of each slit portion 8 is preferably 5mm to 50mm, more preferably 10mm to 45 mm. Thereby, the diffusion of the liquid in the high grammage region 6H becomes more likely to occur. Further, the absorbent core 6 is easily bent and deformed, and the wearing feeling of the diaper 10 is further improved.

In particular, when the respective slit portions 8 are not present on the rear portion R side of the absorbent core 6 at a position corresponding to the feces excretion portion of the wearer, the excreted feces are less likely to adhere to the skin of the wearer, which is preferable. The absence of the rear portion R means that the position of the end T2 on the rear portion R side of all the slits 8 is offset toward the front side F (toward the front side F) from the position corresponding to the feces excretion portion of the wearer.

The slit 8 as described above can be manufactured by providing an air-impermeable convex portion in a collecting concave portion disposed on the outer peripheral surface of the rotary drum at a portion to be the slit 8, in addition to a method of making a notch in the absorbent core 6.

As shown in fig. 7, the slit 8 is preferably formed by joining the core sheets 7 (the skin-side core sheet 71 and the non-skin-side core sheet 72) disposed on the skin surface side and the non-skin surface side of the absorbent core 6 at the position of the slit 8. That is, the skin-side covering sheet 71 and the non-skin-side covering sheet 72 are preferably joined by entering the slit portion 8 from both sides of the absorbent core 6. In this case, the slit portion 8 is more preferably a penetration hole. The joint is more preferably formed so as not to peel off even when wetted with an excretory fluid. This makes it difficult for the super absorbent polymer 67 to move to the position of the slit in the absorbent body 5, and the discolored super absorbent polymer 67 is not easily visible from the outside. Further, the joining of the

core pieces

71, 72 to each other can be performed by various methods for achieving the above-described effects.

Next, the components constituting the diaper 10 will be described.

(absorber 5)

The absorbent body 5 having liquid retentivity can be arbitrarily used without particular limitation as long as it can achieve the effects of the present invention.

The absorbent body 5 preferably contains synthetic fibers. Specific examples of the synthetic fibers include polypropylene fibers, polyethylene fibers, and polyester fibers. Further, of the absorbent core 6 and the core-wrapped sheet 7 constituting the absorbent body 5, at least the absorbent core 6 preferably contains synthetic fibers, and more preferably both the absorbent core 6 and the core-wrapped sheet 7 contain synthetic fibers. The absorbent body 5 is not easily collapsed even when exposed to excretory fluid by containing synthetic fibers. As a result, the discolored super absorbent polymer 67 can be prevented from being seen through the gaps of the deformed absorbent body 5.

In the absorbent core 6, the surface area of the super absorbent polymer 67 is preferably increased toward the skin surface side. The superabsorbent polymer 67 tends to look whiter due to the diffuse reflection of light when the surface area is larger. Thus, even if the superabsorbent polymer 67 in the vicinity of the skin surface side discolors, the diaper 10 can be easily made to look whiter when viewed from the skin surface side.

In addition, the absorber 5 may have an antioxidant. Specific examples of the antioxidant include a hindered phenol antioxidant such as triethylene glycol-bis- [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate ], 1, 6-hexanediol-bis [3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ], octadecyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl propionate and 3, 5-di-tert-butyl-4-hydroxybenzylphosphonate-diethyl ester, and an amine antioxidant such as n-butylamine, triethylamine and diethylaminomethyl methacrylate, and the antioxidant may be contained in either one of the absorbent core 6 and the core-covering sheet 7 constituting the absorbent body 5, or both of them, the synthetic fibers in the absorbent body may be contained, or the hot melt adhesive may be contained. However, the antioxidant may be contained in the super absorbent polymer or may not be contained in the super absorbent polymer. Thus, even when a high-priced super absorbent polymer containing a component for suppressing discoloration is not used, that is, even when a general super absorbent polymer is used, discoloration of the super absorbent polymer can be suppressed in combination with the action based on the structure of the absorbent core 6, and the discoloration can be made inconspicuous when viewed from the outside of the diaper 10.

(dough sheet 3)

The topsheet 3 is liquid-permeable, and the topsheet used in the diaper can be used without particular limitation. From the viewpoint of allowing excreted body fluid to rapidly pass through and move to the absorbent body and the viewpoint of improving the skin feel, a hydrophilic thermally bonded nonwoven fabric is preferable, and a hot air nonwoven fabric is particularly preferable. Preferably, the fibers are thermoplastic resin fibers subjected to hydrophilization treatment and are subjected to a three-dimensional crimp such as 2 crimps or 3 crimps. Specifically, polyethylene, polypropylene, polyester, nylon, and composite fibers thereof are produced, cut to a predetermined length, and coated with various hydrophilizing agents at a stage before short fibers (staples) are formed. Hydrophilization treatment based on a hydrophilizing agent known to those skilled in the art can be used, and as the hydrophilizing agent, various alkylsulfonates typified by α -alkenylsulfonates, acrylates, acrylate/acrylamide copolymers, esteramides, salts of esteramides, polyethylene glycols and derivatives thereof, water-soluble polyester resins, various silicone derivatives, various saccharide derivatives, mixtures thereof, and the like can be used.

The front sheet 3 preferably has a concavo-convex configuration. When the topsheet 3 having the uneven structure is disposed on the skin surface side of the absorbent body, diffuse reflection of light tends to occur on the skin surface side of the topsheet 3, and the diaper 10 tends to look white when viewed from the skin surface side. As a result, the discolored super absorbent polymer 67 is not easily visible from the outside.

The fibers constituting the front sheet 3 are preferably mixed with a color modifier. The color-changing agent is a component having a function of reducing the transmittance of light incident on the front sheet 3 and scattering the light. By mixing the color-changing agent into the constituent fibers of the topsheet 3, the discolored super absorbent polymer 67 is less likely to be seen from the skin surface side.

Specific examples of the color-tone changing agent include inorganic powder and organic powder having a refractive index different from that of the component constituting the fiber of the topsheet 3.

Examples of the inorganic powder include titanium oxide, porous silica (silica), porous silica, Alumina (Alumina), lime, and clay minerals. Examples of the clay mineral include swellable clay mineral (smectite), montmorillonite, bentonite, kaolinite, sericite, illite, cerulite, chlorite, zeolite, talc, and Mizukanite.

Examples of the organic powder include polyethylene powder, polyester powder, polypropylene powder, polyacrylic acid powder, polyacrylate powder, cellulose powder, viscose powder, silk powder, silicone compound powder, and fluorine compound powder. Examples of the material include those obtained by coloring these organic powders with a pigment. Among these, titanium oxide is preferably used as the color tone changing agent.

The amount of the color modifier to be mixed is preferably 0.1% by mass or more, more preferably 1% by mass or more, and still more preferably 3% by mass or more, based on 100% by mass of the entire fibers constituting the topsheet 3. By mixing a certain amount or more of titanium oxide in the constituent fibers of the front sheet 3, light can be effectively scattered. On the other hand, the upper limit of the amount of titanium oxide to be mixed into the constituent fibers of the topsheet 3 is not particularly limited as long as the effects of the present invention can be obtained, and is actually 10 mass% or less.

(Back sheet 4)

As the back sheet 4, a single moisture-permeable film, a composite sheet obtained by laminating a film or a nonwoven fabric, or a water-repellent nonwoven fabric (SMS, SMMS, or the like) can be used. In view of cost, compatibility with a misalignment preventing adhesive, and the like, it is preferable to use a separate moisture permeable film as the leakage preventing member. Examples of the film member in this case include a film obtained by melt-kneading and extruding a thermoplastic resin and an inorganic filler incompatible therewith, the film being stretched to a predetermined size and having fine pores, and a non-porous film which is substantially compatible with moisture and is capable of discharging water vapor, such as a permeable film.

The cover color is preferably provided on the back sheet 4. The position of the cover color and the position where the high absorbent polymer 67 is present in a large amount in the absorbent core 6 are preferably overlapped with each other in a plan view of the absorbent core 51. In particular, when a lovely character such as a rabbit or cat is printed on the back sheet 4 as the cover color, the discoloration of the super absorbent polymer 67 becomes less noticeable from the back sheet 4 side, and is more attractive to the wearer of the diaper 10, which is preferable.

As the outer covering 2 and the side sheet 9 constituting the diaper 10, the elastic members disposed thereon, and the outer-covering nonwoven fabric 48, various materials generally used for such articles can be used for the intermediate member 35.

As described above, in the diaper 10 of the present embodiment, since the discoloration of the super absorbent polymer 67 is not easily seen from the outside, a good appearance can be maintained without using a super absorbent polymer containing a component for suppressing discoloration.

The diaper 10 of the present embodiment is shown as a pants-type diaper, but is not limited thereto, and may be a taped diaper. In the diaper 10 of the present embodiment, the outer package is separated into the front side and the rear side, but the present invention is not limited thereto, and various shapes can be adopted. For example, the outer covering is formed in a shape covering the entire front side portion 10F, the intermediate portion 10C, and the rear side portion 10R of the diaper 10, and is formed in a shape that is retracted in the width direction in the intermediate portion 10C of the diaper 10. The shape of the absorbent core 6 is not limited to the shape of the present embodiment, and various shapes can be adopted. For example, the planar shape of the absorbent core 6 may be a shape that is retracted in the width direction X in the intermediate portion C.

The absorbent article of the present invention includes absorbent articles such as panty liners, incontinence pads, sanitary napkins, and urine collection pads, in addition to the diaper of the above embodiment. In addition, other components matching the purpose or function may be appropriately combined in the above structure.

The present invention further discloses the following absorbent article according to the above embodiment.

<1>

An absorbent article having an absorbent body having an absorbent core and a core-covering sheet covering a skin surface side and a non-skin surface side of the absorbent core, wherein,

at least one of the skin surface side and the non-skin surface side of the absorbent core is provided with a liquid-permeable layer having a liquid-permeable layer L^*a^*b^*At L in the color system^*A value of 40 to 100 a^*A value of-12 or more and 3 or less, b^*A component of a color having a value in the range of-24 or more and 3 or less,

the absorbent core is an assembly of a super absorbent polymer and pulp fibers, the super absorbent polymer is arranged on the skin surface side of the absorbent core,

a joint portion between the absorbent core and the core sheet is disposed on the skin surface side of the absorbent core, and a compartment in which the superabsorbent polymer is surrounded by the joint portion is disposed at least in part on the skin surface side of the absorbent core, thereby defining a region in which the superabsorbent polymer is disposed.

<2>

As described above<1>In the absorbent article, the grammage of the joint portion on the skin surface side of the absorbent core is 3g/m²Above and 10g/m²The following.

<3>

In the absorbent article according to the above <1> or <2>, the joint portion is arranged in a spiral shape.

<4>

The absorbent article according to any one of the above <1> to <3>,

the absorbent core has a longitudinal direction corresponding to a direction in which the front side, the crotch portion, and the rear side of the wearer are joined, and a width direction orthogonal to the longitudinal direction,

the compartments surrounding the superabsorbent polymer are arranged in rows in the longitudinal direction, and 3 or more rows in the width direction.

<5>

The absorbent article according to any one of the above <1> to <4>,

in the absorbent core, the grammage of the super absorbent polymer increases from the non-skin surface side toward the skin surface side.

<6>

The absorbent article according to any one of the above <1> to <5>,

when the absorbent core is divided into a front part on the skin surface side and a back part on the non-skin surface side in the thickness direction, the grammage of the super absorbent polymer in the front part is 40g/m²The above.

<7>

The absorbent article according to any one of the above <1> to <6>,

a front sheet is disposed on the skin surface side of the absorbent body, and an intermediate member is disposed between the absorbent body and the front sheet.

<8>

In the absorbent article according to the above <7>,

the intermediate part is at L^*a^*b^*L shown in the color System^*Achromatic color having a value of 50 or more and 80 or less.

<9>

The absorbent article according to any one of the above <1> to <8>,

l of the absorbent body viewed from the skin surface side of the absorbent article^*a^*b^*L shown in the color System^*The value is 85 or less.

<10>

The absorbent article according to any one of the above <1> to <9>,

the absorbent body has a compressed portion.

<11>

The absorbent article according to any one of the above <1> to <10>,

the absorbent core is provided with slits, and the core-covering sheets disposed on the skin surface side and the non-skin surface side of the absorbent core are joined to each other in the slits.

<12>

The absorbent article according to any one of the above <1> to <11>,

in the absorbent core, the surface area of the super absorbent polymer is increased toward the skin surface side.

<13>

The absorbent article according to any one of the above <1> to <12>,

a back sheet is disposed on the non-skin side of the absorbent body, and the back sheet is disposed with the absorbent body^*a^*b^*At L in the color system^*A value of 40 to 100 a^*A value of-12 or more and 3 or less, b^*A color having a value in the range of-24 or more and 3 or less.

<14>

The absorbent article according to any one of the above <1> to <13>,

a front sheet having an uneven structure is disposed on the skin surface side of the absorbent body.

<15>

The absorbent article according to any one of the above <1> to <14>,

the absorber has an antioxidant.

While the present invention has been illustrated by the description of embodiments and examples thereof, and unless otherwise indicated, it is not intended to be limited to the details shown, but rather it is intended to be interpreted broadly within the spirit of the invention as set forth in the appended claims.

The present application is based on the priority claim of patent application 2019-122080 filed in the japanese country on 6/28/2019, and the content thereof is incorporated by reference as part of the description of the present specification.

Description of reference numerals

1 absorbent body

11 side seal

12 waist opening part

13 leg opening part

2 outer package

21 front side outer package

22 rear side outer body

3 front sheet

35 intermediate part

4 Back sheet

5 absorbent body

55 joint part

56 compartment

56R space

6 absorbent core

61 front face part

62 back side

67 superabsorbent polymer

68 pulp fiber

69 outer edge of skin surface of absorbent core

7 core-spun sheet

71 skin surface side core-covering sheet

72 non-skin surface side core-covering sheet

Lamination of 75 core-clad sheets

8 slit part

9 side sheet

91 elastic member

92 three-dimensional wrinkle part

93 elastic member

94 leg gathers

10 diaper

Front side part of 10F diaper

Middle part of 10C diaper

Rear side portion of 10R diaper

Waistline part of 10D diaper

Front side part of F absorbent core

C intermediate section of absorbent core

R rear side part of absorbent core

Y longitudinal direction of absorbent core (or longitudinal direction of absorbent body)

X width direction of the absorbent core (or width direction of the absorbent main body).

Claims

1. An absorbent article having an absorbent body having an absorbent core and a core-covering sheet covering a skin surface side and a non-skin surface side of the absorbent core, characterized in that:

2. The absorbent article of claim 1, wherein:

the grammage of the joint on the skin surface side of the absorbent core is 3g/m²Above and 10g/m²The following.

3. The absorbent article of claim 1 or 2, wherein:

the engagement portion is configured in a spiral shape.

4. The absorbent article according to any one of claims 1 to 3, wherein:

5. The absorbent article according to any one of claims 1 to 4, wherein:

6. The absorbent article according to any one of claims 1 to 5, wherein:

dividing the absorbent core in the thickness directionWhen the front face portion is positioned on the skin surface side and the back face portion is positioned on the non-skin surface side, the grammage of the super absorbent polymer in the front face portion is 40g/m²The above.

7. The absorbent article according to any one of claims 1 to 6, wherein:

8. The absorbent article of claim 7, wherein:

9. The absorbent article according to any one of claims 1 to 8, wherein:

10. The absorbent article according to any one of claims 1 to 9, wherein:

the absorbent body has a compressed portion.

11. The absorbent article according to any one of claims 1 to 10, wherein:

12. The absorbent article according to any one of claims 1 to 11, wherein:

13. The absorbent article according to any one of claims 1 to 12, wherein:

14. The absorbent article according to any one of claims 1 to 13, wherein:

15. The absorbent article according to any one of claims 1 to 14, wherein:

the absorber has an antioxidant.