JP7281310B2 - absorbent article - Google Patents

Description

The present invention relates to absorbent articles such as diapers and sanitary napkins.

Techniques have been proposed for reducing skin troubles of wearers in absorbent articles such as diapers and sanitary napkins.
For example, Patent Literature 1 describes an absorbent article in which a skin-care agent is applied to the skin-contacting surface side of a surface sheet having a high-density portion and a low-density portion. Further, in the absorbent article described in Patent Document 2, it is described that a raised portion is formed in the laminated topsheet and a high-density portion is formed in the raised portion in order to reduce skin troubles due to breathability.

JP 2011-131044 A JP-A-2006-263296

The skin care agent applied to the surface sheet migrates to the skin and exerts its effect. Although the skin care agent can sufficiently migrate to the skin at the initial stage of wearing the absorbent article, the amount of the skin care agent remaining on the surface sheet decreases with the passage of wearing time and excretion. Therefore, conventionally, the longer the wear time is, the less the amount of skin care agent transferred to the skin due to the influence of excretion, and the less the skin care effect.
SUMMARY OF THE INVENTION In view of the above points, the present invention provides an absorbent article that can enhance the durability of the effect of a skin care agent.

The present invention provides an absorbent article comprising a topsheet on a skin-contacting side, a backsheet on a non-skin-contacting side, and an absorbent body interposed between the topsheet and the backsheet, wherein The surface sheet has projections containing a skin care agent on the side of the surface that contacts the skin, and the projections consist of two ridges and a recess sandwiched between the two ridges in a cross-sectional view in the thickness direction. and wherein more skin care agent is placed in the depressions than in the ridges.

The absorbent article of the present invention can enhance the durability of the effects of skin care agents.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a partially cutaway plan view of a tape-type diaper as one embodiment of the present invention, which is unfolded and viewed from the skin contact surface side; FIG. 2 is an enlarged cross-sectional view taken along line II-II of FIG. 1, and the figure inside the circle indicated by symbol P is an enlarged cross-sectional view of the convex portion. (A) is a cross-sectional view showing a state in which the protrusion is obliquely raised, and (B) is a cross-sectional view showing a state in which the protrusion is bent in the middle of the protrusion. FIG. 11 is a partially enlarged perspective view showing a mode in which the projection has a truncated cone shape; It is a one-section perspective view which shows the aspect which a convex part has a streaky shape. FIG. 4 is a cross-sectional view showing a mode in which the surface sheet is composed of a first nonwoven fabric and a second nonwoven fabric. FIG. 4 is a cross-sectional view showing a mode in which the surface sheet has high convex portions and low convex portions; FIG. 4 is a partially enlarged plan view showing an arrangement pattern when projections having depressions containing a skin care agent are arranged over the entire topsheet. (A) is a partially enlarged plan view showing an arrangement pattern in which projections having depressions containing a skin care agent are scattered in a grid pattern in the planar direction of the surface sheet; 4] is a partially enlarged plan view showing an arrangement pattern in which rows of projections having depressions in which skin care agents are arranged are intermittently arranged in the width direction X in the longitudinal direction Y. [FIG. FIG. 2 is a plan view showing an aspect of arranging rows of protrusions having depressions in which a skin care agent is placed in a plurality of striped regions of the topsheet of the diaper shown in FIG. 1 .

A diaper 10 as a preferred embodiment of an absorbent article according to the present invention will be described below with reference to the drawings. In addition, although the diaper 10 is shown as a tape type in FIG. 1, it is not limited to this, and may be, for example, a pants type.

In the present invention, the side that comes into contact with the wearer's skin is referred to as the skin side, skin contact side, or surface side, and the opposite side is referred to as the non-skin side, non-skin contact side, or back side. These terms are also used as terms that indicate relative positional relationships in the member configuration of the absorbent article, even for members that do not have a surface that contacts the wearer's skin. In addition, the direction to the front of the wearer when worn is referred to as the front, and the direction to the rear is referred to as the rear. The normal direction of the front surface or back surface of the absorbent article is referred to as the thickness direction. The front side is the wearer's ventral side, and the back side is the wearer's dorsal side.

FIG. 1 shows a state in which the diaper 10 of the present embodiment is expanded and viewed from the side of the skin contact surface. In this state, the diaper 10 is divided into a front side portion F, a crotch portion C, and a rear side portion R, which are arranged on the wearer's front side, crotch portion, and rear side, respectively. It has a longitudinal direction Y corresponding to the direction in which Rs are connected, and a width direction X orthogonal to the longitudinal direction Y.

The diaper 10 comprises, as constituent members, a topsheet 1 arranged on the skin-contacting side, a leak-proof backsheet 2 arranged on the non-skin-contacting side, and a space between the topsheet 1 and the backsheet 2. It has an absorbent body 3 interposed in.
The surface sheet 1 is preferably made of a liquid-permeable soft material, for example, a hydrophilic non-woven fabric. In this embodiment, the topsheet 1 is described as being made of a hydrophilic nonwoven fabric.
The absorbent body 3 has an aggregate of excretory fluid absorbent materials (hereinafter also referred to as an absorbent core), for example, an aggregate of pulp fibers or an aggregate of pulp fibers and a superabsorbent polymer material. From the viewpoint of shape retention, the absorbent core is preferably covered with a hydrophilic covering sheet (not shown). The backsheet 2 is preferably made of a member having a leakproof property, and for example, preferably a breathable moisture-permeable film laminated with an exterior nonwoven fabric that feels good on the skin.

In this embodiment, a pair of side sheets 8 , 8 are arranged on the side of the skin contacting surface of the top sheet 1 so as to extend outward in the width direction X from both sides in the longitudinal direction Y. As shown in FIG. The diaper 10 has an outer shape in which the crotch portion C is constricted, and the front side portion F and the rear side portion R protrude in the width direction. Projected portions of the front side portion F and the rear side portion R form a pair of left and right front side flaps 10A and rear side flaps 10B. Fastening tapes 9, 9 used for fixing the diaper 10 to the wearer's body are arranged on the widthwise outer edges of the rear side flaps 10B.

Next, the surface sheet 1 will be described in detail.
The surface sheet 1 has projections 6 on the side of the skin contacting surface. The topsheet 1 of the present embodiment has an uneven structure 5 having a plurality of protrusions 6 and recesses 7 between the protrusions 6 . In the concave-convex structure 5 , a plurality of convex portions 6 and concave portions 7 are alternately arranged in the planar direction of the skin-contacting surface of the topsheet 1 . The protrusions 6 may be present on the entire region of the skin-contacting side of the topsheet 1 or may be present on a part of the region. It is preferable that the projections 6 are arranged at least in the region where the topsheet touches the wearer's skin. For example, the topsheet 1 shown in FIG. It is preferable that the convex portion 6 is arranged in the area M1 extending in the longitudinal direction Y of the sheet 1 . Regarding the longitudinal direction Y, the protrusions 6 are preferably arranged in the area where the absorbent body 3 exists, and are arranged in at least the area covering the buttocks from the excretion site (area of 200 mm across the center in the longitudinal direction of the product). It is more preferable to be Further, it is preferable that the concave-convex structure 5 including the convex portion 6 is also arranged within the above range. This makes it easier for the agent to migrate to areas where skin troubles tend to occur, facilitating effective care for those areas. In the present invention, the number of projections is not limited to that of the above embodiment, and is appropriately determined according to the size, shape, etc. of the absorbent article. There may be.

As shown in FIG. 2, skin care agent 4 is contained on convex portion 6 . “On the convex portion 6” means the surface of the convex portion 6 (the surface facing the skin contact surface side).

式中、Ｒ^１は、ヒドロキシ基及び／又はアルコキシ基が置換していてもよい、炭素数１～２２の直鎖又は分岐鎖の炭化水素基を示し、Ｒ^２は、炭素数１～１２の直鎖又は分岐鎖の二価の炭化水素基を示し、Ｒ^３は、炭素数１～４２の直鎖又は分岐鎖の二価の炭化水素基を示す。 The skin care agent used in the present invention will be explained. As the skin care agent used in the present invention, any agent having effects such as protection and healing of the wearer's skin can be used without particular limitation. For example, preferred skin care agents include diamide derivatives represented by the following formula (I). The diamide derivative represented by the following formula (I) is the diamide derivative of the invention described in International Publication WO00/61097, and has the medicinal effect of improving the water retention capacity and barrier function of the stratum corneum. ing. When the diamide derivative migrates to the wearer's skin while wearing the absorbent article, it functions as an oily skin care agent and can suppress/ameliorate skin rashes.

In the formula, R ¹ represents a linear or branched hydrocarbon group having 1 to 22 carbon atoms which may be substituted with a hydroxy group and/or an alkoxy group, and R ² represents a hydrocarbon group having 1 to 12 carbon atoms. represents a linear or branched divalent hydrocarbon group, and R ³ represents a linear or branched divalent hydrocarbon group having 1 to 42 carbon atoms;

When the diamide derivative is used as a skin care agent, only one type of diamide derivative may be used, or two or more types may be used in combination.
Other skin care agents that can be used in the present invention include, for example, skin care agents that are used as emollient agents in the field of cosmetics. Specific examples of other skin care agents include liquid paraffin, silicone oil, animal and vegetable oils (olive oil, jojoba oil, safflower oil, squalane, squalene, etc.), monoglycerides, diglycerides, triglycerides, aliphatic ethers (myristyl-1,3-dimethyl butyl ether, palmityl-1,3-dimethylbutyl ether, stearyl-1,3-dimethylbutyl ether, palmityl-1,3-methylpropyl ether, stearyl-1,3-methylpropyl ether, etc.), isostearyl-cholesterol ester, paraffin wax , C12-C22 fatty acids, C12-C44 fatty acid ethers, C12-C22 fatty alcohols, petroleum jelly, fatty acid sorbitan esters (monoesters, diesters, and triesters), polyoxyethylene fatty acid sorbitan esters (monoesters, diesters) , and triesters.), metal stone test (magnesium stearate, etc.), sucrose fatty acid ester, cyclodextrin fatty acid ester, silicone, silicone resin, JP-A-2004-298643 or JP-A-2008-522772 Examples include an emollient used in the invention described in the publication and a lotion composition containing an emollient and a fixing agent. The various hydrophilic skin care agents may be used singly or in combination of two or more.

Preferred embodiments of the skin care agent include those that are in a solid form with low fluidity and tend to stay on convex portions before being worn, and that become semi-solid and fluid when heated by body temperature or the like during wearing. This makes it possible to achieve more effective continuous migration of the skin care agent in the structure of the projections 6, which will be described later.

The convex portion 6 protrudes toward the skin contact surface. As for the relative positional relationship along the direction in which the convex portion 6 protrudes, the side nearer to the position where it touches the skin is called the upper side, and the farther side is called the lower side. Further, the height H1 of the protrusion 6 is divided into two equal parts, and the part closer to the position that touches the skin is divided into an upper part 6T, and the part below the upper part 6T is divided into a root part 6N. The "protrusion height H1 of the protrusion 6" is the thickness from the highest part to the lowest part of the skin contact surface side surface of the protrusion 6 in a side view (or a cross-sectional view in the thickness direction) of the protrusion 6. Say the distance in the direction. This distance can be determined by observing a cross section in the thickness direction using, for example, a digital microscope (manufactured by KEYENCE CORPORATION). It can be measured by the height at the shortest distance in the thickness direction. In addition, the above-mentioned "cross-sectional view in the thickness direction" refers to observing a cross-section cut along a plane along the thickness direction of the topsheet 1 from a direction orthogonal to the cross-section.

As shown in FIG. 2 , the convex portion 6 has two peak portions 61 and a recess portion 62 sandwiched between the two peak portions 61 in a cross-sectional view in the thickness direction. In addition, the above-mentioned rule is a cross-section in the thickness direction passing through the recessed portion 62 among various cross-sections in the thickness direction of the convex portion 6, and the above requirements (two ridges 61 and two ridges 61 It means that there is at least one cross section that satisfies the requirements for the recessed portion 62 sandwiched between the . Therefore, it is not necessary to satisfy the above requirements for all possible cross sections.
The peak portion 61 and the recess portion 62 are arranged on the upper portion 6T of the convex portion 6 . It is preferable that the ridges 61 and the depressions 62 are located in the portion of the upper portion 6T that comes into contact with the wearer's skin. Specifically, it is preferable that at least part of the ridge portion 61 of each convex portion 6 is positioned at the highest elevation height H1 of the convex portion 6 . It is preferable that the depression 62 is arranged adjacent to the ridge 61 at the highest height H1 of the protrusion 6 .

The protrusions 6 are not limited to those protruding perpendicularly to the planar direction of the surface sheet 1 as shown in FIG. For example, as shown in FIGS. 3(A) and 3(B), there may be a slanted protuberance or a protuberance that is bent in the middle of the protuberance. No matter what shape the projections 6 have, the projection height H1 of the projections 6 is, as described above, from the highest portion to the lowest portion of the skin-contacting surface side surface of the projections 6. is the distance in the thickness direction of Moreover, the height of the ridges 61 may be uniform or non-uniform in the individual projections 6 . Furthermore, the height of the ridges 61 may be uniform or non-uniform between the convex portions 6 .

The ridge portion 61 is formed according to the shape of the convex portion 6 .
For example, as shown in FIG. 4, when the individual projections 6 are independent frustums, the ridges 61 are formed in an annular shape when the projections 6 are viewed from above. In this case, the recessed portion 62 is arranged in a region surrounded by the annular peak portion 61 in plan view. In addition, when the peak portion 61 is annular, the annular shape may be a complete ring without a break, or may have a part where the ring is interrupted in the middle. When the projections 6 have a truncated cone shape, the projections 6 preferably have a truncated cone shape from the viewpoint of enhancing the soft feel of the surface sheet 1, and the shape of the ridges 61 in a plan view is preferably circular. .
Further, when each convex portion 6 is formed in a stripe shape in the plane direction as shown in FIG. 5, the ridge portion 61 is also formed in a stripe shape accordingly. In this case, two streaky ridges 61 are arranged in parallel, and a depression 62 is arranged in a region sandwiched between the ridges 61 and 62 . In the case of the streak-like ridge portion 61, the streak may have no discontinuity, or may have a discontinuous portion in the middle of the streak.
4 and 5, two ridges 61, 61 and a recess 62 therebetween can be seen in the cross section of the projection 6 in the thickness direction passing through the recess 62. As shown in FIG.

From the viewpoint of enhancing the soft feel of the topsheet 1, the ridges 61 preferably have rounded ends. Moreover, the ridge 61 preferably has an inclined surface (tapered shape) that descends from the tip toward the recess 62 in order to facilitate the transfer of the skin care agent 4 to the skin.

As shown in FIGS. 2, 3A and 3B, the recess 62 is adjacent to the ridge 61 and opens toward the skin contact surface. Further, the recessed portion 62 is a portion that is shallowly recessed with a height less than the height H1 of the protrusion 6 to the extent that the protruding shape of the protrusion 6 is not damaged. The depth H2 of the depressions 62 is preferably 50% or less, more preferably 40% or less, of the raised height H1 of the projections 6 from the viewpoint of maintaining the soft touch and cushioning properties of the uneven structure 5 of the topsheet 1. preferable. In addition, the depth H2 of the recessed portion 62 is preferably 10% or more, more preferably 20% or more, with respect to the raised height H1 of the convex portion 6 from the viewpoint of enhancing the durability of the skin care effect described below. The depth H2 of the recessed portion 62 applies mutatis mutandis to the above-described method for measuring the "protrusion height H1 of the convex portion 6", and is based on the highest portion of the peak portion 61, and is the depth from this position. can be measured as In addition, the recessed portion 62 is not limited to being arranged at one location for one convex portion 6 as shown in FIGS. 2, 3A and 3B, and may be arranged at a plurality of locations. .

In each convex portion 6 , more skin care agent 4 is arranged in the concave portion 62 than in the peak portion 61 . The amount of the skin care agent 4 here refers to the amount of the skin care agent 4 present on the surfaces of the peaks 61 and the recesses 62 on the side of the skin contact surface. The magnitude relationship of the amount of skin care agent 4 can be measured by the following method.

(Method for evaluating size relationship of amount of skin care agent)
Infrared spectroscopy (IR) can be used as a method for evaluating the magnitude relationship of the amount of the skin care agent 4 . When comparing areas with a large amount of skin care agent 4 and areas with a small amount of skin care agent 4, it is possible to determine areas with a large amount and a small amount of skin care agent by comparing the height of the infrared absorption peak derived from the target skin care agent obtained by IR. is. In other words, it can be determined that more skin care agents 4 are present when the infrared absorption peak is higher (the amount of absorption is greater).
The ATR method can be used for infrared spectroscopy, and if the range to be measured is sufficiently wide, any of the absorption peaks obtained by direct measurement (macro: 2 to 3 mm) (for example, the above-mentioned diamide derivative In the case of , the absorption peak of the amide group at 3300 cm ⁻¹ ) can be compared. Also, when the site to be measured is small, it is preferable to use a microscope (100 μm).
As an example, the procedure for the above measurement is shown below.
Measuring device: PerkinElmer Spectrum One (+Multiscope)
Macro measurement: ATR probe uses diamond for single reflection Microscopic measurement: ATR probe uses germanium Wave number resolution: 4 cm ^-1
Accumulation times: 4 times (macro measurement), 16 times (microscopic measurement)

Due to the arrangement of the skin care agent, the skin care agent 4 stays in the depression 62 in the upper part 6T of the projection 6 that contacts the skin, and even if the skin care agent 4 is arranged in a small amount, it can be efficiently transferred to the skin. can be done. In addition, in the convex portion 6 that contacts the skin, the recessed portion 62 serves as a storage portion for the skin care agent 4, and the skin care agent 4 is stored not only at the same height as the peak portion 61 but also at a position lower than the peak portion 61. It can be stably held by fastening. Further, the recessed portion 62 can prevent the skin care agent 4 from falling off physically or running down due to excrement. On the other hand, the ridges 61 adjacent to the recesses 62 come into contact with the skin surface to transfer the skin care agent 4 to the skin. In addition, the ridges 61 can also receive the skin care agent 4 from the adjacent recessed portions 62, which facilitates continued transfer of the skin care agent 4 to the skin. The supply of the skin care agent 4 from the depressions 62 to the peaks 61 may be triggered by, for example, contact or rubbing between the topsheet 1 and the skin surface. Further, depending on the degree of contact or rubbing between the topsheet 1 and the skin surface, the skin care agent 4 staying in the recessed portions 62 may come into direct contact with the skin surface due to strong pressure on the ridges 61 . These migrations are more likely to occur when the fluidity of the skin care agent 4 is increased by warming due to body temperature or the like.
As a result, the combination of the ridges 61 and the depressions 62 in the projections 6 allows the skin care agent 4 to gradually and continuously migrate to the skin, enhancing the durability of the skin care effect. As a result, the diaper 10 can maintain a good wearing feeling for a long time.
Further, in the diaper 10, the surface sheet 1 has the protrusions 6, so that the contact area between the surface sheet 1 and the wearer's skin can be reduced, and the breathability can be improved. This breathability and the durability of the skin care effect mentioned above are combined to further enhance the comfortable wearing feeling of the diaper 10 .

Based on the above measurement method, the ratio Q1/Q2 of the amount Q1 of the skin care agent 4 in the depressions 62 to the amount Q2 of the skin care agent 4 in the peaks 61 enhances the continuous migration of the skin care agent 4 to the skin. From a viewpoint, 1.1/1 or more is preferable, 1.2/1 or more is more preferable, and 1.5/1 or more is still more preferable. From the viewpoint of suppressing inhibition of absorption performance, the ratio Q1/Q2 is preferably 20/1 or less, more preferably 10/1 or less, and even more preferably 5/1 or less.

By distributing the amount of the skin care agent 4 according to the above ratio to the peaks 61 and the recesses 62, the amount of the skin care agent 4 in the entire surface sheet 1 can be suppressed without being excessive. As a result, the skin care agent is continuously transferred to the skin surface while inhibiting absorption performance, which is preferable. From this point of view, the amount of the skin care agent 4 applied to the topsheet 1 is preferably 5 g/m ² or less, more preferably 3 g/m ² or less, and even more preferably 1 g/m ² or less. The amount of the skin care agent 4 applied to the surface sheet 1 is preferably 0.01 g/m ² or more, more preferably 0.05 g/m ^{2 or} more, and more preferably 0.1 g, from the viewpoint of sufficiently exhibiting the skin care effect. /m ² or more is more preferable. The amount of the skin care agent can be obtained by selecting an appropriate solvent according to the type of skin care agent, extracting from the surface sheet 1, and quantifying using gas chromatography (GC) or high performance liquid chromatography (HPLC). . Further, the amount of the skin care agent per unit area can be obtained by dividing the quantified amount of the skin care agent by the area of the surface sheet 1 to be extracted. As the solvent to be used, one or a combination of two or more of highly polar solvents (highly polar solvents) such as methanol and ethanol, non-polar solvents such as hexane, or solvents less polar than highly polar solvents can be used. can be done.

The convex portion 6 may have a hollow portion 63 as shown in FIGS. 2 to 5, or may be solid without a hollow portion 63 (not shown). However, it is preferable that the convex portion 6 has a hollow portion 63 . As a result, even if the load on the topsheet 1 changes as the wearer moves, the protrusions 6 flexibly follow the skin surface, and the above-mentioned skin care agent 4 is continuously transferred to the skin. can be expressed. In addition, it is possible to improve the soft touch and cushioning properties of the convex portion 6 .

2 to 5, the surface sheet 1 is shown as being made of one sheet of nonwoven fabric. A specific example thereof is shown in FIG. In the topsheet 1 shown in FIG. 6, the first nonwoven fabric 11 on the skin-contacting side has the uneven structure 5 and is joined to the flat second nonwoven fabric 12 on the non-skin contacting side. The second nonwoven fabric 12 is preferably joined to the bottom surface 71 of the recess 7 of the first nonwoven fabric 11 . The bonding between the first nonwoven fabric 11 and the second nonwoven fabric 12 may be performed by an adhesive or by thermal fusion bonding of embossing. The hollow portion 63 is surrounded by the first nonwoven fabric 11 and the second nonwoven fabric 12, and the joining portion between the first nonwoven fabric 11 and the second nonwoven fabric 12 is arranged around the hollow portion 63, thereby forming the hollow portion 63 and the The shape stability of the enclosing convex portion 6 is increased. As a result, the skin care agent 4 can be more stably transferred to the skin by the peaks 61 and the depressions 62 described above. In addition, the soft texture and cushioning properties of the protrusions 6 are well expressed.

The projections 6 of the topsheet 1 can be produced by various methods commonly used in absorbent articles. For example, when the non-woven fabric constituting the surface sheet 1 is formed by the air-through method, the fibrous web before fusion bonding is placed on the uneven support and subjected to hot air treatment to shape the unevenness to form the convex portions 6 . can do. A non-woven fabric or fiber web may be formed into unevenness using a tooth groove roll or the like. In the case of using a tooth groove roll, one sheet of nonwoven fabric may be formed into unevenness, and at the same time, it may be heat-sealed with another sheet of flat nonwoven fabric in the recesses to form protrusions 6 as shown in FIG. Alternatively, the non-woven fabric or fiber web may be unevenly formed by intermittent embossing. In this case, heat-shrinkable fibers may be included in predetermined regions of the fiber web, and after intermittent embossing, the non-embossed portions may be raised by hot air processing to form protrusions, and the embossed portions may be formed as recesses. good.
The recessed portion 62 in the convex portion 6 can be formed after forming the convex portion 6 . Various methods commonly used in absorbent articles can be employed to form the recessed portion 62 . For example, a method of forming depressions by thermal compression so as to crush them, a method of applying a mechanical force after shaping to give dents to the tops, and a vent opening in advance at the tops of the projections of the uneven support. and a method of sucking from the inside of the convex portion by providing a recess having a .

Application of the skin care agent 4 to the projections 6 can be performed by various methods commonly used in absorbent articles. In particular, it is preferable to apply the coating while applying a predetermined pressure using a contact coater. As a result, more skin care agent 4 can be placed in the depressions 62 than in the ridges 61 more reliably.

In this embodiment, it is preferable that the root wall portion 64 of the protrusion 6 has a higher fiber density than the wall portion (hereinafter referred to as the upper wall portion) 65 above the root wall portion 64 . The fiber density in each wall means the number of fibers per unit area on the surface of the topsheet 1 . When the root wall portion 64 of the convex portion 6 has a high fiber density as described above, the number of fibers is larger than that of the upper wall portion 65 of the root wall portion 64 of the convex portion 6 (the inter-fiber distance is small). It is a dense area. Since the fiber density of the root wall portion 64 is high, the shape of the convex portion 6 can be maintained. In addition, the upper wall portion 65 and the recessed portion 62 are more easily deformed than the base wall portion 64, and in the wearing state, the regions that are most likely to come into contact with the wearer's skin can achieve a good touch with a soft touch. In addition, the “root wall portion 64” referred to here is the surface portion of the convex portion 6 in the root portion 6N described above. Further, the "upper wall portion 65" refers to the surface portion of the convex portion 6 in the upper portion 6T described above.

(Method of Measuring Fiber Density of Root Wall 64 and Upper Wall 65 of Projection 6)
In the present invention, the "fiber density" of the base wall portion 64 and the upper wall portion 65 is such that the convex portion The root wall portion 6 and the upper wall portion 65 of 6 are each observed with an optical microscope, and the unit area of the surface of the root wall portion 64 and the upper wall portion 65 portion of the predetermined sheet (the first nonwoven fabric 11 in FIG. 6) Calculated by measuring the number of fibers.

Based on the above measuring method, the ratio S1/S2 of the fiber density S1 of the base wall portion 64 to the fiber density S2 of the upper wall portion 65 of the base wall portion 64 is the soft touch of the convex portion 6 and the overall strength of the convex portion 6. From the viewpoint of achieving both resistance to crushing, it is preferably 1.1/1 or more, more preferably 1.25/1 or more, and even more preferably 1.5/1 or more. In addition, the ratio S1/S2 is preferably 5/1 or less, more preferably 4/1 or less, and 3/1 or less from the viewpoint of absorption performance, soft touch of the protrusions 6, and resistance to crushing of the protrusions 6 as a whole. is more preferred.

The difference in fiber density as described above can be formed, for example, by the method described in each example of JP-A-2012-136790. A web supplied from a carding machine to a web shaping device is fixed on a pedestal having many projections and having air permeability, and then hot air is blown to the fiber web on the pedestal to hit the projections on the pedestal. A method of forming a fibrous web and fusing the fibers of each core-sheath structure can be mentioned. According to this method, the area of the web driven away from the pedestal by the hot air has a lower fiber density, and the area of the web closer to the pedestal has a relatively higher fiber density because the distance over which the fibers are driven is short. .

In the present embodiment, the topsheet 1 may include high convex portions 66 and low convex portions 67 lower in height than the high convex portions 66, as shown in FIG. In this case, the high convex portion 66 is preferably the convex portion 6 having the recessed portion 62 containing the skin care agent 4 . That is, the high convex portion 66 has two peak portions 61 and a recess portion 62 sandwiched between the two peak portions 61 in a cross-sectional view in the thickness direction. It is preferable that many skin care agents are distributed. This makes it possible to more stably achieve continuous transfer of the skin care agent 4 to the wearer's skin. In this case, as long as the depressions 62 containing the skin care agent 4 are arranged in the high projections 66 , the depressions 62 containing the skin care agent 4 may also be arranged in the low projections 67 .

In the present embodiment, the projections 6 having the depressions 62 containing the skin care agent 4 are placed against the skin-contacting side of the topsheet 1 as long as the skin care agent 4 is continuously transferred to the skin. It can be arranged in various patterns.

For example, an area extending from the center L in the width direction X of the diaper 10 in the longitudinal direction Y of the topsheet 1 with a predetermined width (the topsheet 1 is not covered with the pair of side sheets 8, 8 and is exposed) is shown in FIG. A convex portion 6 having a concave portion 62 containing a skin care agent 4 may be arranged over the entire area M1. As a result, the range in which the skin care agent can be continuously transferred is widened, which is preferable. As a specific example, the projections 6 may be formed into an independent frustum shape as shown in FIG. 4, and all of the projections 6 may be provided with depressions 62 containing the skin care agent 4 as shown in FIG.

On the other hand, projections 6 having depressions 62 containing the skin care agent 4 may be scattered in the plane direction of the topsheet 1 with respect to the region M1. In the case of the interspersed arrangement, the skin care agent preferentially migrates to the skin on the convex portions without the depressions at the initial stage, and the skin care agent continuously migrates to the skin on the convex portions having the depressions 62. You can effectively maintain the skin care effect from to the passage of time. In addition, by leaving the convex portions without the recessed portions, it is possible to ensure the cushioning properties, air permeability, and liquid permeability of the surface material, which is preferable. The interspersed arrangement may be either regular interspersed arrangement or irregular interspersed arrangement.
As a specific example of the regular interspersed arrangement, as shown in FIG. 9A, there is an arrangement pattern in which the projections 6 having the depressions 62 containing the skin care agent 4 are arranged in an oblique grid pattern. Here, between the convex portions 6, 6 having the concave portion 62 containing the skin care agent 4, the convex portion 69 without the concave portion 62 is arranged. In the case of the oblique lattice arrangement, the projections 69 without the depressions 62 and the projections 6 with the depressions 62 can be uniformly arranged in a lattice pattern, and the uniform skin care effect and the cushioning of the surface material can be obtained. It is preferable because it is possible to ensure all of retention, air permeability and liquid permeability. Note that the convex portion 69 without the recessed portion 62 may contain a skin care agent or may not contain a skin care agent.
Further, as shown in FIG. 9(B), there is an arrangement pattern in which rows of protrusions 6 having depressions 62 containing the skin care agent 4 are arranged in the longitudinal direction Y intermittently in the width direction X (striped arrangement). mentioned. In this case, as shown in FIG. 10, in the region M1, rows of convex portions 6 having recessed portions 62 containing the skin care agent 4 are arranged in a plurality of striped regions M2, and adjacent to the region M2. A row of protrusions 69 without recesses 62 is arranged in the region M3. In this arrangement pattern, the convex portions 69 without the recessed portions 62 and the convex portions 6 having the recessed portions 62 can be arranged in stripes, and the above-mentioned skin care effect, the cushion retention property of the surface material, and the breathability in the vertical direction can be obtained. and liquid permeability can be ensured, which is preferable. Note that the convex portion 69 without the recessed portion 62 may contain a skin care agent or may not contain a skin care agent. As a modification of this, as shown in FIG. 9C, the arrangement pattern may be such that convex portions 68 having recessed portions 62 that do not contain the skin care agent 4 are arranged in the region M3. In this case, the skin care agent can be applied in stripes, the amount of the skin care agent can be reduced, and the liquid permeation performance can be ensured, which is preferable.
9(B) and 9(C), each row in which the projections 6 having the depressions 62 containing the skin care agent 4 are arranged in the longitudinal direction Y is arranged in the region M2. is not limited to For example, two or more rows may be bundled to form the region M2. In this case, lateral air permeability and liquid permeability can be ensured, which is preferable. The arrangement of stripes is not limited to the case of using mutually independent frustum-shaped projections 6 as shown in FIG. may be intermittently arranged in the width direction X. In this case, it can be arranged in stripes in the vertical direction, and even if the diaper is twisted in the vertical direction, it is possible to maintain the skin care transfer effect, vertical breathability, and liquid permeation performance. It is preferable because it can enhance the effect of preventing diffusion of stool into the body.

Moreover, in the topsheet 1, the shape, number, and size of the projections 6 are not limited to those shown in FIGS. The convex portion 6 is provided with a ridge portion 61 and a recess portion 62 sandwiched between the ridge portions 61, and the skin care agent 4 is arranged in a specific arrangement so that the above-described skin care agent 4 is more stably transferred to the skin continuously. As long as the shape, number, and size of the projections 6 can be appropriately set.

For the constituent members of the diaper 10 of this embodiment, materials that are commonly used in absorbent articles can be used without particular limitation. Other members may be appropriately incorporated in addition to the constituent members described above. Further, the structure of the diaper 10 is not limited to that shown in FIG. 1, but is a combination of a vertically long absorbent main unit (top sheet, back sheet, and absorbent body) and an exterior body separated into a front side portion and a rear side portion. It can be anything.

The absorbent article of the present invention is not limited to the above embodiments. As described above, it can be applied to various absorbent articles as long as the surface sheet 1 has the ridges 61 and the depressions 62 on the projections 6 and the skin care agent 4 is distributed more in the depressions 62 than in the ridges 61. can do. For example, not only tape-type diapers but also pants-type diapers may be used, and various types of diapers such as incontinence pads, sanitary napkins, and panty liners are worn in contact with the wearer's skin to absorb excrement. Applicable to goods.

1 Top sheet 2 Back sheet 3 Absorber 4 Skin care agent 5 Concavo-convex structure 6 Convex portion 61 Ridge portion 62 Hollow portion 63 Hollow portion 64 Root wall portion 65 Wall portion above the root wall portion (upper wall portion)
66 high convex portion 67 low convex portion 7 concave portion 8 side sheet 9 fastening tape 10 diaper 10A front side flap 10B rear side flap

Claims (4)

An absorbent article comprising a topsheet on a skin-contacting side, a backsheet on a non-skin-contacting side, and an absorbent body interposed between the topsheet and the backsheet,
The surface sheet has a convex portion containing a skin care agent on the side of the skin contacting surface,
In a cross-sectional view in the thickness direction, the projection has two ridges and a recess sandwiched between the two ridges at the top of the upper part of the ridge that touches the wearer's skin. and
The two ridges in a cross-sectional view in the thickness direction are connected to form an annular shape in a plan view of the protrusion, and the recess is arranged in a region surrounded by the annular ridges,
The absorbent article, wherein more skin care agent is disposed in the depressions than in the peaks. 2. The absorbent article of claim 1, wherein the root wall portion of said protrusion has a higher fiber density than the wall portion above said root wall portion. 3. The surface sheet according to claim 1 or 2, wherein the surface sheet comprises high convex portions and low convex portions whose height is lower than the high convex portions, and the high convex portions are convex portions containing the skin care agent. absorbent article. 4. The absorbent article according to any one of claims 1 to 3, wherein the projections containing the skin care agent are scattered in the planar direction of the topsheet.

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