JP2018079036A - Absorbent article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorbent article excellent in sweat absorption property and leakage prevention property.SOLUTION: A sweat absorption sheet 10 has a configuration in which a hydrophilicity agent is partially adhered to a nonwoven fabric formed of fibers containing a hydrophobic resin, and partially has hydrophilic property. In plan view of the sweat absorption sheet 10, there are plural hydrophilic parts 11 to which the hydrophilicity agent is adhered, and on a surrounding of each of the plural hydrophilic parts 11, there is a hydrophobic part 12 to which no hydrophilicity agent is adhered. The sweat absorption sheet 10 is arranged on a surface material non-existence area which does not overlap to the surface material when an absorbent article is extended and projected in a thickness direction. The sweat absorption sheet 10 is arranged closest to a skin of a wearer, or is overlapped to a non-skin facing surface of the hydrophilic nonwoven fabric which is arranged closest to a skin of a wearer in the surface material non-existence area.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an absorbent article provided with a sweat-absorbing sheet having a sweat-absorbing action.

  Conventionally, in absorbent articles such as disposable diapers, for the purpose of reducing skin troubles such as sweats, a sweat-absorbing sheet made of a hydrophilic material has been placed on a part that can come into contact with the wearer's skin when worn. ing.

  Patent Documents 1 to 6 describe partial hydrophilic sheets in which a hydrophilic portion and a hydrophobic portion are mixed on the skin facing surface facing the wearer's skin. The partially hydrophilic sheets described in Patent Documents 1 to 5 are subjected to a hydrophobizing treatment on a part of an inherently hydrophilic sheet such as a hydrophilic non-woven fabric. Specifically, for example, embossing is performed by attaching a hydrophobizing agent. Either processed or processed, or contains both hydrophilic and hydrophobic fibers as constituent fibers. In addition, the partially hydrophilic sheet described in Patent Document 6 is partially applied by applying a hydrophilic lotion composition having a water solubility of 30% in a stripe shape to the surface sheet or the leak-proof cuff in the absorbent article. It is attached to.

JP-T-2001-521590 JP 2004-358099 A JP 2004-16441 A JP 2011-182816 A JP 2016-112165 A Special table 2010-526663

  The sweat-absorbent sheet in the absorbent article is required to have both a sweat-absorbing property that can absorb sweat and a leak-proof property that does not leak body fluid such as urine to the outside. The techniques related to the partially hydrophilic sheet described in Patent Documents 1 to 6 have room for improvement in order to achieve both sweat absorption and leakage prevention. In addition, the conventional sweat-absorbent sheet has a slow transpiration rate of absorbed sweat, so that it takes a long time to absorb the sweat until it evaporates. If it comes into contact with the wearer's skin for a long time, it causes skin troubles such as rash. Therefore, the sweat absorbency required for the sweat absorbing sheet includes not only simply absorbing sweat but also allowing the absorbed sweat to evaporate quickly. No sweat-absorbing sheet has yet been provided that has a sweat-absorbing property that absorbs sweat and can quickly evaporate, and also has an excellent leak-proof property.

  Therefore, the subject of this invention is related with providing the absorbent article which is excellent in perspiration and leak-proof property.

  The present invention is an absorbent article comprising a liquid-retaining absorbent body and a surface material disposed closer to the wearer's skin than the absorbent body. A sweat-absorbing sheet is disposed in a surface material non-existing region that does not overlap the surface material when projected in a direction, and the sweat-absorbing sheet is closest to the wearer's skin in the surface material non-existing region. It is arranged on the non-skin facing surface of the hydrophilic non-woven fabric arranged closest to the skin of the wearer, and the sweat-absorbent sheet is a non-woven fabric composed of fibers containing a hydrophobic resin. It has a structure in which the hydrophilizing agent is partially attached, and is partially hydrophilic, and in the plan view of the sweat-absorbent sheet, a plurality of hydrophilic portions to which the hydrophilizing agent is attached are scattered, Hydrophobic part where the hydrophilic agent is not attached around each of the hydrophilic parts It is an absorbent article that exist.

  ADVANTAGE OF THE INVENTION According to this invention, the absorbent article which is excellent in sweat absorbency and leak-proof property is provided.

FIG. 1 is a perspective view schematically showing a pants-type disposable diaper that is an embodiment of the absorbent article of the present invention. FIG. 2 is a developed plan view schematically showing the skin facing surface side (inner surface side) in the developed and extended state of the diaper shown in FIG. FIG. 3 is a cross-sectional view schematically showing a cross section taken along line II of FIG. FIG. 4 is an exploded perspective view schematically showing the diaper shown in FIG. 1 in an exploded manner. Fig.5 (a) is a top view which shows typically an example of the sweat-absorbing sheet which concerns on this invention, FIG.5 (b) is typical in the cross section along the thickness direction of the sweat-absorbing sheet shown to Fig.5 (a). FIG. FIG. 6 is a plan view schematically showing a sweat-absorbing sheet outside the scope of the present invention. FIG. 7 is a developed plan view schematically showing the skin facing surface side (inner surface side) in the developed and extended state of the developed disposable diaper that is another embodiment of the absorbent article of the present invention. 8 is a cross-sectional view schematically showing a cross section taken along line II-II in FIG.

  The present invention will be described below based on preferred embodiments with reference to the drawings. 1 to 4 show a pants-type disposable diaper 1A which is an embodiment of the absorbent article of the present invention. As shown in FIG. 3, the diaper 1 </ b> A includes a liquid-retaining absorbent body 23 and a surface sheet 21 as a surface material disposed on the side closer to the wearer's skin than the absorbent body 23.

  As shown in FIGS. 1 to 4, the diaper 1 </ b> A has a longitudinal direction X corresponding to the wearer's front-rear direction and a lateral direction Y orthogonal to the wearer's front-rear direction. The crotch part B includes an abdominal part A and a dorsal part C that extend in the direction X, and a liquid-retaining absorbent 23. The crotch part B is a part disposed in the crotch part of the wearer when the diaper 1A is worn, and the abdomen side part A is the abdomen side of the wearer, that is, the longitudinal direction X rather than the crotch B when the diaper 1A is worn. The back side portion C is a portion arranged on the back side of the wearer, that is, on the rear side in the longitudinal direction X, rather than the crotch portion B in the wearing state of the diaper 1A.

  The diaper 1 </ b> A includes the absorbent main body 2 including the absorbent body 23 in the center portion in the lateral direction Y, and the non-skin facing surface side of the absorbent main body 2, that is, the side farther from the wearer's body than the absorbent main body 2. The side edges AS, CS along the longitudinal direction X of the exterior body 3 in each of the abdominal side A and the back side C are adhesive, heat seal, ultrasonic seal, etc. A pair of side seal portions S, S, a waist opening WH through which the wearer's torso is passed, and a pair through which the wearer's lower limb is passed, as shown in FIG. Leg openings LH and LH are formed.

  The absorptive main body 2 has a rectangular shape in plan view when the diaper 1A is expanded and extended as shown in FIG. 2, and extends in the longitudinal direction X from the ventral side A to the dorsal side C. Is aligned with the longitudinal direction X of the diaper 1 </ b> A in the unfolded and extended state, and is arranged at the center in the lateral direction Y of the exterior body 3, and is joined to the exterior body 3 with an adhesive. The “expanded and extended state” of the diaper 1A means that the diaper 1A is separated by the side seal portion S to be in the expanded state, and the expanded diaper 1A is extended by the elastic member of each part (designed dimensions are not affected by the elastic member at all). It means a state in which it is expanded until it becomes the same size as when it is expanded in a flat state in the excluded state.

  As shown in FIG. 3, the absorbent main body 2 includes a liquid-permeable surface sheet 21 that forms a skin-facing surface, and a liquid-impermeable or liquid-permeable or water-repellent back sheet 22 that forms a non-skin-facing surface. And a liquid-retaining absorbent 23 interposed between the two sheets 21 and 22, which are integrated by a known joining means such as an adhesive. In the present embodiment, the absorbent body 23 includes a liquid-retaining absorbent core 231 and a core wrap sheet 232 that covers the outer surface (both skin facing surface and non-skin facing surface) of the absorbent core 231. It consists of The absorbent core 231 and the core wrap sheet 232 are joined by a known joining means such as a hot melt adhesive.

  In the present specification, the “skin-opposing surface” is a surface of the absorbent article or a component thereof (for example, a surface sheet) that is directed toward the wearer's skin when the absorbent article is worn, that is, the skin of the wearer relatively. The “non-skin facing surface” is a surface that is directed to the side opposite to the skin side when the absorbent article is worn, that is, relatively far from the wearer's skin. On the side. In addition, "at the time of wearing" here means a state where a normal proper wearing position, that is, a correct wearing position of the absorbent article is maintained, and the absorbent article is in a state of being deviated from the wearing position. Is not included.

  As the absorbent core 231 and the core wrap sheet 232 constituting the top sheet 21, the back sheet 22, and the absorber 23, various types conventionally used for this type of absorbent article can be used without any particular limitation. it can. For example, various nonwoven fabrics or apertured films can be used as the top sheet 21, and a resin film, a laminate of a resin film and a nonwoven fabric, or the like can be used as the back sheet 22. The absorbent core 231 is a deposit of a core forming material including an absorbent material. As the absorbent material, those normally used as a material for forming this type of absorbent core can be used without any particular limitation. For example, hydrophilic fibers such as wood pulp, synthetic fibers treated with a hydrophilizing agent, and water absorption Include polymer particles. That is, the absorbent core 231 can be a hydrophilic fiber stack, or a structure in which water-absorbing polymer particles are supported on the stack. As the core wrap sheet 232, a liquid permeable sheet such as paper or nonwoven fabric can be used.

  As shown in FIGS. 2 and 3, the left and right side portions along the longitudinal direction X on the skin-facing surface of the absorbent main body 2 are composed of a liquid-resistant or water-repellent and breathable leak-proof cuff forming sheet 25. A pair of leak-proof cuffs 24, 24 are provided. In the vicinity of the free end of each leak-proof cuff 24, one or more elastic members 26 for forming a leak-proof cuff are arranged in an elongated state in the longitudinal direction X. The leak-proof cuff 24 stands up at least at the crotch B when the elastic member 26 arranged in the stretched state contracts when the diaper 1A is worn, so that the excretion fluid such as urine flows out in the lateral direction Y. To prevent.

  The outer package 3 forms the outer shape of the diaper 1A in the unfolded and extended state as shown in FIG. 2, and the outer periphery of the outer package 3 has contour lines of the diaper 1A in the state, that is, the ventral side A, the crotch B, and A contour line of each of the back side portions C is formed. As shown in FIG. 2, the exterior body 3 has a rectangular shape in which the length in the lateral direction Y is longer than the longitudinal direction X in the abdominal side A and the back side C. In the crotch part B located between C and C, both side edges along the longitudinal direction X of the outer package 3, that is, the pair of leg edge parts LS, LS are curved in a convex arc shape toward the center in the lateral direction Y. In the plan view as shown in FIG. 2, the central area in the vertical direction X forms an hourglass shape that is bound inward in the horizontal direction Y.

  As shown in FIGS. 3 and 4, the outer package 3 includes an outer layer sheet 31 that forms an outer surface of the diaper 1 </ b> A, that is, a non-skin facing surface, and an inner layer sheet 32 that is disposed to face the skin facing surface of the outer layer sheet 31. It is comprised including the laminated body. In the wearing state of the diaper 1A, the outer layer sheet 31 is located on the side far from the wearer's body, forms the non-skin facing surface (outer surface) of the diaper 1A, and the inner layer sheet 32 is located on the side closer to the wearer's body. And the skin opposing surface (inner surface) of 1 A of diapers is formed. The outer layer sheet 31 and the inner layer sheet 32 are joined to each other at a predetermined site via joining means such as heat sealing, ultrasonic sealing, and adhesive. As shown in FIG. 4, the outer layer sheet 31 extends from the edge in the longitudinal direction X of the inner layer sheet 32 to the ventral side portion A and the back side portion C, and is folded back to the skin facing surface side of the inner layer sheet 32. As shown in FIG. 2, the folded portion 31 </ b> E covers an end portion in the longitudinal direction X of the absorbent main body 2.

  In the present embodiment, as shown in FIG. 4, the inner layer sheet 32 is composed of a single continuous sheet, whereas the outer layer sheet 31 is composed of a combination of a plurality of sheets. Specifically, a ventral outer layer sheet 31A constituting the ventral part A, a dorsal outer layer sheet 31C constituting the dorsal part C, and a crotch outer layer constituting the crotch part B located between the sheets 31A and 31C. A sheet 31B is included. Each of the sheets 31A, 31B, 31C constituting the outer layer sheet 31 is overlapped with each other in the longitudinal direction X, and a known joining such as an adhesive, a heat seal, a high frequency seal, an ultrasonic seal, etc. They are joined and integrated by means. In the overlapping portion of the sheets 31A and 31C and the sheet 31B, the sheet 31B located in the center of the longitudinal direction X is located on the side relatively close to the absorbent main body 2, and both ends of the sheet 31B in the longitudinal direction X The non-skin facing surface of the part is covered with sheets 31A and 31C. As with the outer layer sheet 31, the inner layer sheet 32 may be a combination of a plurality of sheets.

  The sheets 31 (31A, 31B, 31C) and 32 constituting the exterior body 3 may be the same type of sheets or different types of sheets, and examples of the latter include different forms of stretchability. Specifically, for example, as the ventral outer layer sheet 31A and the back outer layer sheet 31C, an elastic sheet having elasticity in the lateral direction Y is used, and the remaining part of the outer layer sheet 31, that is, the crotch outer layer sheet 31B and the inner layer sheet 32 are A non-stretchable sheet that does not have stretchability can be used. Examples of the stretchable sheet that can be used as the exterior body 3 include a stretchable sheet in which stretchable fiber layers are integrated on both sides or one side of the elastic fiber layer, and includes an elastic fiber layer and a stretchable fiber layer. Examples of the integration method include a method of laminating both layers and hydroentangling, a method of entangling fibers by air-through, etc., a method of joining by heat embossing, an adhesive, ultrasonic waves, and the like. In addition, examples of the non-stretchable sheet that can be used as the outer package 3 include nonwoven fabrics produced by various manufacturing methods, and specific examples include spunbond nonwoven fabrics, air-through nonwoven fabrics, and needle punched nonwoven fabrics.

  As shown in FIGS. 1, 2, and 4, a plurality of thread-like or belt-like waist elastic members 33 are arranged in the lateral direction Y on the abdominal side A and the back side C, respectively. The book waist elastic members 33 are intermittently arranged at a predetermined interval in the longitudinal direction X. As described above, the waist elastic member 33 is arranged in a state where the elastic stretchability is expressed, so that the opening edge of the waist opening WH has an annular waist that is substantially continuous over the entire circumference. A gather is formed. Further, a leg elastic member 34 for forming one or a plurality of leg gathers in the form of threads or strips is arranged in an extended state on the leg edge LS that forms the opening edge of each of the pair of leg openings LH, LH. As a result, an annular leg gather substantially continuous over the entire circumference is formed at the opening edge of each of the pair of leg openings LH, LH. Each of these elastic members 33 and 34 is sandwiched and fixed between the outer layer sheet 31 and the inner layer sheet 32 constituting the exterior body 3 by a bonding means such as an adhesive.

  As one of the main features of the diaper 1A, when the diaper 1A is unfolded and projected in the thickness direction (in other words, in the plan view of the unfolded and elongated diaper 1A as shown in FIG. 2), it overlaps with the topsheet 21. The point which the sweat-absorbing sheet is distribute | arranged to the surface material non-existence area | region N (part shown with the oblique line in FIG. 2) which cannot become is mentioned. In the diaper 1A, the surface sheet 21 is arranged almost in the entire area in the plan view of the absorbent main body 2, and therefore the surface material non-existing region N of the diaper 1A is as shown in FIG. Matches a non-placed area. The sweat-absorbent sheet is disposed in a part or the whole of the surface material non-existing region N.

  The sweat-absorbent sheet according to the present invention has a property of absorbing sweat. Sweat is a secretion from a sweat gland, and usually 99% by mass or more thereof is water, most of the remainder is sodium chloride, and additionally contains urea, lactic acid and the like. Having perspiration means the property of absorbing one or more drops out of 10 drops in the following droplet evaluation. In the following droplet evaluation, the sweat-absorbent sheet according to the present invention can preferably absorb 3 drops or more, more preferably 5 drops or more in 10 drops.

<Droplet evaluation>
Evaluation is carried out in accordance with the method of AATCC 118-1983. A sheet to be evaluated (nonwoven fabric) is placed on a filter paper (hard filter paper 4A manufactured by ADVANTEC) so that the skin-facing surface is the upper surface, and the sheet is vertically viewed from a height of about 0.6 cm from the upper surface of the sheet. On the other hand, 10 drops of 0.05 ml droplets are dropped at different positions at intervals of about 4 cm. The liquid to be dropped is deionized water. At 30 ± 2 seconds after each drop, the number of drops that penetrated or absorbed into the sheet out of the 10 drops dropped (this method is shown in FIG. 1 in the method of AATCC 118-1983). Corresponding to C or D). The measurement is performed five times, and the average value is rounded off to an integer to obtain the droplet evaluation result of the sheet. The measurement environment is a room temperature of 22 ± 2 ° C. and a humidity of 65 ± 2% RH. It shows that the more the number of droplets penetrating into the sheet, the higher the sweat absorption of the sheet.

  In the case where the constituent member (for example, a sweat-absorbent sheet) is taken out from the absorbent article for evaluation and measurement, if the constituent member is fixed to another constituent member with an adhesive or the like, it is bonded with liquid nitrogen. The agent is cooled to facilitate peeling of the constituent members. When the component member is fixed to another component member by fusion or the like, the component member is peeled off by hand, or the fusion part is cut and removed by a cutter knife or the like. When gathers are formed by an elastic member or the like, evaluation is performed with the gathers stretched and widened.

  The sweat-absorbent sheet according to the present invention has a configuration in which a hydrophilizing agent is partially attached to a nonwoven fabric (base nonwoven fabric) made of fibers containing a hydrophobic resin, and is partially hydrophilic. FIG. 5 shows a sweat absorbent sheet 10 which is an example of the sweat absorbent sheet according to the present invention. The sweat-absorbent sheet 10 is made of a single non-woven fabric, and in a plan view as shown in FIG. 5A, a plurality of hydrophilic portions 11 to which a hydrophilizing agent is attached are scattered, and around each of the plurality of hydrophilic portions 11, There is a hydrophobic portion 12 to which a hydrophilizing agent is not attached. 5A shows only the skin-facing surface 10a of the sweat-absorbent sheet 10, the hydrophilic portion of the skin-facing surface 10a also on the non-skin facing surface 10b located on the opposite side of the skin-facing surface 10a. The hydrophilic part 11 exists in the position corresponding to 11, and the hydrophilic part 11 and the hydrophobic part 12 are mixed like the skin facing surface 10a. The plurality of hydrophilic portions 11 are present over the entire length in the thickness direction of the sweat-absorbent sheet 10 as shown in FIG.

  The sweat-absorbing sheet disposed in the absorbent article is required to have a leak-proof property capable of preventing leakage of body fluid such as urine to the outside in addition to the sweat-absorbing property capable of absorbing sweat. In order for the sweat-absorbent sheet to have leak-proof properties, it is necessary to have hydrophobicity. However, if the entire surface of the sweat-absorbent sheet facing the skin is hydrophobic, the sweat-absorbing property is impaired. Therefore, in order for the sweat-absorbent sheet to have both sweat-absorbing properties and leak-proof properties, both the hydrophilic portion (hydrophilic portion) and the hydrophobic portion (hydrophobic portion) must be present on the skin facing surface. On the other hand, on the skin-facing surface of the sweat-absorbent sheet, if the hydrophobic part is present, the total area of the hydrophilic part necessary for the expression of the sweat-absorbing function, which is the most important function, is relatively reduced. There is a concern about a decrease in sweat absorption function. However, the sweat to be absorbed by the sweat-absorbent sheet is not secreted from the entire surface of the skin in the human body, but is secreted from a large number of sweat glands scattered in the skin. That is, the sweat secretion location is scattered on the skin surface of the wearer of the absorbent article. Then, in order for the sweat-absorbing sheet to have a practically sufficient sweat-absorbing property, it is sufficient to have a hydrophilic portion at a position corresponding to the sweat secretion site on the skin-facing surface, and the entire surface of the skin-facing surface is hydrophilic. It can be said that there is no need to be a department. From the above, it can be said that a partial hydrophilic sheet in which a hydrophilic portion and a hydrophobic portion are mixed, such as the sweat-absorbent sheet 10, is appropriate as the sweat-absorbing sheet having both sweat-absorbing properties and leak-proof properties.

  Moreover, as described in JP-A-2003-536002, for example, as a sweat-absorbing sheet, a hydrophilic nonwoven fabric and a hydrophobic nonwoven fabric are simply laminated, and the hydrophilic nonwoven fabric is placed on the skin facing surface side, the hydrophobic nonwoven fabric. Is the non-skin facing side, since the entire non-skin facing side is a hydrophobic part, leakage due to penetration of body fluids in the thickness direction of the sheet can be suppressed, but the entire skin facing side is Since it is hydrophilic, sweat tends to remain on the skin-facing surface side, thus making it easier to feel stickiness, and also regarding leakage prevention, the flow of bodily fluids in the surface direction of the seat cannot be inhibited, so-called transmission leakage occurs. There is room for improvement.

  Further, for example, the sweat-absorbent sheet 90 shown in FIG. 6 is a partial hydrophilic sheet prepared by applying a hydrophobizing agent in a lattice pattern on the surface of a nonwoven fabric (base nonwoven fabric) made of hydrophilic fibers, as shown in FIG. In a plan view of such a skin facing surface, a hydrophobic portion 91 to which a hydrophobizing agent is attached is intermittently disposed, and a hydrophilic portion 92 to which the hydrophobizing agent is not attached is present around the hydrophobic portion 91. Here, in terms of product design, the sweat-absorbent sheet 90 has a lattice shape in which the hydrophobic portion 91 is a continuous line in a plan view corresponding to the application pattern of the hydrophobizing agent, and the portion corresponding to the eyes of the lattice is hydrophilic. Since the portion 92 has the pattern in which the body portion 92 is located, the body fluid flowing on the skin-facing surface of the sweat-absorbent sheet 90 can be blocked by the hydrophobic portion 91, and leakage of the body fluid can be effectively suppressed. However, in the sweat-absorbent sheet 90 actually manufactured according to the product design, it is possible to prevent repelling of the hydrophobizing agent due to the difference in surface tension between the hydrophilic application target surface and the hydrophobizing agent applied thereto. Since it is difficult at present, the hydrophobic portion 91 may not be a continuous line as designed in a plan view but a discontinuous line as shown in FIG. Therefore, the body fluid flowing on the skin-facing surface of the sweat-absorbent sheet 90 may leak to the outside through the discontinuous portion of the hydrophobic portion 91, that is, the hydrophilic portion 92, as indicated by arrows in FIG. Accordingly, it can be said that the sweat-absorbent sheet 90 obtained by partially adhering the hydrophobizing agent to the hydrophilic nonwoven fabric has room for improvement in terms of leak-proof property, although the sweat-absorbent property is sufficient.

  On the other hand, since the sweat-absorbent sheet according to the present invention is based on a nonwoven fabric made of fibers containing a hydrophobic resin, compared to the sweat-absorbent sheet 90 based on a nonwoven fabric made of hydrophilic fibers, Essentially leak-proof. For example, also in the sweat-absorbent sheet 10 shown in FIG. 5, due to the repelling of the hydrophilizing agent due to the surface tension difference between the hydrophobic application target surface and the hydrophilizing agent applied thereto, If the shape in plan view does not conform to the product design, and if it conforms to the product design, it should have a circular shape as shown in FIG. 5, but in reality, a part of the circle may be missing. However, even if this is the case, it is the hydrophilic portion 11 that does not contribute to the leak-proof property that does not become as designed, and the hydrophobic portion 12 that contributes to the leak-proof property is a portion that the non-woven fabric used as the base originally has Therefore, regardless of the success or failure of the application of the hydrophilizing agent, it occupies a large proportion on the skin-facing surface of the sweat-absorbent sheet 10 or is present with continuity in the surface direction. The flow of body fluid on the skin-facing surface is easily inhibited by the hydrophobic portion 12, and the sweat-absorbent sheet 10 is excellent in leakage prevention. On the other hand, with respect to the sweat absorbency, it may be somewhat inferior to the sweat absorbable sheet 90 because it is essentially based on a hydrophobic nonwoven fabric. However, as described above, sweat secretion scattered on the skin surface is practically used. Since it is sufficient to have a hydrophilic property (hydrophilic portion) corresponding to the location, it is possible to ensure a practically sufficient sweat absorbency by paying attention to the pattern of the hydrophilic portion. That is, the sweat-absorbent sheet according to the present invention, represented by the sweat-absorbent sheet 10 shown in FIG.

  In the sweat-absorbent sheet according to the present invention, the hydrophilic portion is a region where the fiber contact angle measured by the following method is less than 100 degrees, and the hydrophobic portion is a region where the contact angle is 100 degrees or more. The smaller the contact angle of the fiber measured by the following method, the higher the hydrophilicity (lower hydrophobicity), and the higher the contact angle, the lower the hydrophilicity (higher hydrophobicity).

<Measurement method of contact angle>
Set so that the cross-section along the thickness direction of the sheet (nonwoven fabric) to be measured is the top surface, and randomly sample multiple fibers in the section from the outermost surface of the sheet to 1/10 of the thickness in the sheet thickness direction. Measure the contact angle. As a measuring device, an automatic contact angle meter MCA-J manufactured by Kyowa Interface Science Co., Ltd. is used. Distilled water is used to measure the contact angle. The amount of liquid ejected from an ink jet type water droplet ejection part (manufactured by Cluster Technology Co., Ltd., pulse injector CTC-25 with a pore diameter of 25 μm) is set to 15 picoliters, and the water droplets are directly above the center of each fiber. Dripping. The state of dripping is recorded on a high-speed recording device connected to a horizontally installed camera. The recording device is preferably a personal computer incorporating a high-speed capture device from the viewpoint of image analysis later. In this measurement, an image is recorded every 17 msec. In the recorded video, the first image of water droplets on the fiber is attached to the attached software FAMAS (software version is 2.6.2, analysis method is droplet method, analysis method is θ / 2 method, image processing algorithm Is non-reflective, the image processing image mode is frame, the threshold level is 200, and the curvature is not corrected)), and the angle between the surface of the water droplet that touches the air and the fiber is calculated and contacted. A corner. The fiber is cut into a fiber length of about 1 mm, and the fiber is placed on a sample table of a contact angle meter and kept horizontal. N = 5 contact angles are measured to one decimal place, and a value obtained by averaging a total of 10 measured values (rounded to the first decimal place) is defined as the contact angle. A lower contact angle means higher hydrophilicity. The measurement environment is a room temperature of 22 ± 2 ° C. and a humidity of 65 ± 2% RH.

  In the sweat-absorbent sheet 10, as shown in FIG. 5A, a plurality of hydrophilic portions 11 having a circular shape in plan view are arranged in a dotted pattern on the skin facing surface 10 a of the sheet 10, and the hydrophilic portions 11 are intermittent. Pattern. The hydrophobic portion 12 surrounds each hydrophilic portion 11 and is continuous on the skin facing surface 10a. That is, in the plan view of the sweat-absorbent sheet 10, the plurality of hydrophilic portions 11 exist independently in the hydrophobic portion 12 having a size as a grouped region. In the present invention, the pattern of the hydrophilic portion of the sweat-absorbent sheet is not limited to the pattern shown in FIG. 5 and can be arbitrarily set. For example, the hydrophilic portion 11 having a linear shape in plan view extending in one direction is orthogonal to the one direction. A so-called stripe pattern in which a plurality of stripes are intermittently arranged in the direction in which the pattern is formed can be used, and examples of variations of the stripe pattern include a spiral pattern, a continuous wave pattern, a zigzag pattern, and a pattern in which Ω characters are continuous. In any case, the hydrophilic part 11 is preferably an intermittent pattern, that is, a pattern in which the hydrophilic part 11 and the hydrophobic part 12 are alternately arranged in one direction of the surface of the sweat-absorbent sheet 10. Examples of the planar view shape of the hydrophilic portion 11 include a dot shape such as a circle, an ellipse, a triangle, a quadrangle, and a hexagon; and a line shape such as a straight line, a curve, and a broken line. In addition, the plurality of hydrophilic portions existing on one surface of the sweat-absorbent sheet may have the same or different shapes in plan view.

As described above, the hydrophilic portion on the skin-facing surface of the sweat-absorbent sheet is preferably present corresponding to sweat secretion sites (sweat glands) scattered on the skin surface of the wearer of the absorbent article. In this respect, the distribution density of sweat glands in the human body is about 130 to 600 pieces / cm ² , and the distance between the sweat glands is about 0.31 to 0.66 mm in the shortest part. The one corresponding to the pattern is preferable, and thereby the sweat drawing property by the sweat-absorbent sheet can be further improved. From such a viewpoint, on the skin facing surface 10a of the sweat-absorbent sheet 10, the pitch P (see FIG. 5B) between the two hydrophilic portions 11 and 11 adjacent to each other with the hydrophobic portion 12 interposed therebetween is preferably 0. It is 3 mm or more, more preferably 0.7 mm or more, and preferably 20 mm or less, more preferably 5 mm or less, specifically preferably 0.3 to 20 mm, more preferably 0.7 to 5 mm. Further, the gap G between the two hydrophilic portions 11 and 11 (see FIG. 5B) is preferably 0.2 mm or more, more preferably 0.5 mm or more in the shortest part of the gap G, and The thickness is preferably 10 mm or less, more preferably 4 mm or less, specifically preferably 0.2 to 10 mm, and more preferably 0.5 to 4 mm. In addition, when the planar shape of the hydrophilic portion 11 is a dot shape such as a circle, the maximum passing length on the skin facing surface 10a side (for example, the diameter when the hydrophilic portion 11 is circular in plan view) is preferably 0. .15 mm or more, more preferably 0.3 mm or more, and preferably 10 mm or less, more preferably 2.5 mm or less, specifically preferably 0.15 to 10 mm, more preferably 0.3 to 2.5 mm. It is.

  In the sweat-absorbent sheet according to the present invention, it is preferable that the hydrophilic property differs between the skin facing surface side surface layer portion and the non-skin facing surface side surface layer portion. Specifically, the difference in hydrophilicity between the skin facing surface side surface portion and the non-skin facing surface side surface layer portion of the sweat-absorbent sheet is, for example, A) of the total area of the hydrophilic portion in the total area of the surface The ratio (hereinafter, also referred to as “hydrophilic area ratio”), B) the type of hydrophilizing agent that adheres to the sweat-absorbent sheet, and C) the concentration of the hydrophilizing agent. Regarding A), the larger the hydrophilic part area ratio, the higher the hydrophilicity of the surface (lower hydrophobicity), and regarding C), the higher the concentration of the hydrophilizing agent, the higher the hydrophilicity of the surface ( Low hydrophobicity). In any one or more of A) to C), the hydrophilicity (hydrophobicity) of the two is different from each other between the skin facing surface side surface portion and the non-skin facing surface side surface layer portion of the sweat-absorbent sheet. As a result, a hydrophilic gradient is generated in the thickness direction of the sweat-absorbent sheet, so that the sweat-withdrawing property by the sweat-absorbent sheet is improved, which can lead to further improvement of the sweat-absorbing property. The hydrophilic part area ratio can be measured by the following method.

<Measurement method of hydrophilic part area ratio>
A sheet (nonwoven fabric) to be measured is placed with its one surface (skin facing surface or non-skin facing surface) facing up, and distilled water is placed on the one surface (measuring surface) according to the above <Method for Measuring Contact Angle>. Are dropped at a pitch of 0.1 mm in one direction (longitudinal direction) and one direction (lateral direction) perpendicular to the one direction, and for each dropping point, the <contact angle measuring method> Measure the contact angle according to When the measured value of the contact angle is less than 90 degrees, the dropping point is a hydrophilic point, and when the measured value is 90 degrees or more, the dropping point is a hydrophobic point. And, while drawing only a line connecting only each hydrophilic point, drawing a line connecting only each hydrophobic point, with a line passing through an intermediate point between the two adjacent lines as a boundary, the line side connecting the hydrophilic points is a hydrophilic part, A line connecting the hydrophobic points is defined as a hydrophobic portion. In addition, when the adhesion state of the hydrophilizing agent is uneven on the surface to be measured due to repellency of the hydrophilizing agent, there may be hydrophobic points in the hydrophilic part. If the ratio of the number of hydrophobic points to the number of dropping points is 30% or less, the hydrophobic points are regarded as a part of the hydrophilic portion. The same applies to the handling of hydrophilic points that may exist in the hydrophobic part. The hydrophilic part area ratio can be determined as a ratio (%) of the area of the hydrophilic part to the total area of the measurement target surface.

  In the present invention, the “surface layer portion on the skin-facing surface side of the sweat-absorbent sheet” is a distance corresponding to 1/10 of the thickness of the sheet in the thickness direction of the sheet from the outermost surface on the skin-facing surface side of the sweat-absorbing sheet. It means an area that extends over a distance. In addition, the “non-skin-facing surface-side surface layer portion of the sweat-absorbing sheet” is a distance corresponding to 1/10 of the thickness of the sheet in the thickness direction of the sheet from the outermost surface on the non-skin-facing surface side of the sweat-absorbing sheet. It means an area that extends over a distance. In addition, the “outermost surface of the sweat-absorbent sheet” referred to here is a contour located on the outermost side in the thickness direction when the cross section along the thickness direction of the sweat-absorbent sheet is observed with an optical microscope magnified about 50 times. Means a line.

  In the sweat-absorbent sheet according to the present invention, it is preferable that the skin facing surface side surface layer portion has a lower hydrophilicity than the non-skin facing surface side surface layer portion. A sweat-absorbing sheet with such a hydrophilic gradient in the thickness direction excels in sweat-absorbing and quick-drying properties, absorbs sweat quickly and evaporates quickly, and also prevents leakage of body fluids such as urine. It can be effectively suppressed. In particular, in order to improve the quick-drying property of the sweat-absorbent sheet, that is, the sweat transpiration ability, it is effective to increase the diffusibility of the absorbed sweat sheet in the surface direction. It is effective to make the hydrophilicity of the skin-facing surface side surface layer portion higher than that of the skin-facing surface-side surface layer portion (making the hydrophilicity of the skin-facing surface-side surface layer portion lower than that of the non-skin-facing surface-side surface layer portion).

  In the sweat-absorbent sheet according to the present invention, as a preferred example of a form in which the skin facing surface side surface layer portion has a lower hydrophilicity than the non-skin facing surface side surface layer portion, the skin facing surface side surface layer portion is less The form with a small hydrophilic part area rate is mentioned compared with the skin facing surface side surface layer part. The sweat-absorbent sheet 10 shown in FIG. 5 is an example of such a form. In the sweat-absorbent sheet 10, each hydrophilic portion 11 exists over the entire length in the thickness direction of the sweat-absorbent sheet 10 as shown in FIG. 5B, but the area on the skin facing surface 10 a is less. Since it is smaller than the area on the skin facing surface 10b, the hydrophilic part area ratio of the skin facing surface 10a side surface layer portion is smaller than that of the non-skin facing surface 10b side surface layer portion, and the skin facing surface 10a side surface layer portion has a hydrophobic portion. There are relatively many 12s. Therefore, the sweat-absorbent sheet 10 is excellent in quick-drying, can quickly evaporate absorbed sweat, and has high water pressure resistance, so that body fluids such as urine and menstrual blood permeate the sweat-absorbent sheet 10 in the thickness direction and absorb it. Inconveniences such as adhering to clothing of the wearer of the property article hardly occur. Moreover, the hydrophilic part 11 in the skin opposing surface 10a of the sweat-absorbent sheet 10 has relatively few opportunities to touch the skin of the wearer of the absorbent article, and is excellent in dry feeling.

  The ratio of the hydrophilic part area ratio of the skin facing surface side surface layer part of the sweat-absorbent sheet to the hydrophilic part area ratio of the non skin facing surface side surface layer part is the hydrophilic part area ratio of the skin facing surface side surface layer part / non-skin facing surface side The area ratio of the hydrophilic part of the surface layer part is preferably 0.2 or more, more preferably 0.4 or more, and preferably 0.8 or less, more preferably 0.7 or less. The ratio or the hydrophilic area ratio is adjusted by applying the concentration, viscosity, printing pressure, temperature, etc. of the hydrophilizing agent to be adhered to the nonwoven fabric (base nonwoven fabric) made of fibers containing a hydrophobic resin in the production of the sweat-absorbent sheet. It can be carried out by appropriately adjusting the coating speed in this case.

The area ratio of the hydrophilic portion of the skin-facing surface side surface layer portion of the sweat-absorbent sheet is preferably 10% or more, more preferably 20% or more, and preferably 70% or less, more preferably 50% or less. When the hydrophilic portion area ratio of the skin-facing surface side surface layer portion of the sweat-absorbent sheet is within such a range, the water-resistant pressure and the Klem water absorption height of the sweat-absorbent sheet are each in the preferred ranges described below, and as a result, the body fluid leaks out. Inconveniences such as dirt on clothes can be effectively suppressed.
Moreover, the hydrophilic part area ratio of the non-skin facing surface side surface layer part of the sweat-absorbent sheet is preferably 20% or more, more preferably 30% or more, and preferably 80% or less, more preferably 60% or less.

  The water-resistant pressure of the sweat-absorbent sheet according to the present invention is improved in leakproofness, particularly that body fluid such as urine and menstrual blood permeates the sweat-absorbent sheet in the thickness direction and adheres to the wearer's clothing of the absorbent article. From the viewpoint of preventing the above, it is preferably 5 mm or more, more preferably 10 mm or more, and preferably 40 mm or less, more preferably 30 mm or less. The water pressure resistance of the sweat-absorbing sheet can be adjusted by adjusting the contact angle of the fiber surface with the hydrophilizing agent of the sweat-absorbing sheet, the adhesion amount of the hydrophilizing agent, and the hydrophilic part area ratio. The water pressure resistance is measured by the following method.

<Measurement method of water pressure resistance>
The measurement method conforms to JIS L1092 (Test method for waterproofness of textile products). The test is performed by the hydrostatic pressure method A (reducing pressure method), and a leveling device that can be raised at a speed of 100 mm / min ± 5 mm / min is used. The measurement is performed three times, and the average value is taken as the water pressure resistance of the sheet.

  In addition, from the viewpoint of improving leakage prevention, in particular, leakage of body fluid such as urine and the like flowing through the surface of the sheet, and preventing so-called side leakage, the sweat absorption sheet according to the present invention preferably has a clem water absorption height of 0 mm. More preferably, it is 1 mm or more, preferably 10 mm or less, more preferably 5 mm or less. The smaller the Klem water absorption value, the more difficult it is for the body fluid to flow on the surface of the sweat-absorbent sheet. The height of water absorption by the clem can be adjusted by adjusting the interfiber distance and the hydrophilic area ratio of the sweat-absorbent sheet. Klem water absorption height is measured by the following method.

<Measurement method of Klem water absorption height>
The measurement method conforms to JIS P8141. The measurement target sheet (nonwoven fabric) is cut into a rectangular shape in plan view having a length of 200 mm and a width of 20 mm to obtain a measurement sample, and the longitudinal direction of the measurement sample is made to coincide with the vertical direction, and a portion extending 15 mm upward from the lower end of the measurement sample. Soak in water in a container. The rising height of the water in the measurement sample after 10 minutes from the immersion in water is measured, and the measured value is taken as the Klem water absorption height. From the viewpoint of facilitating measurement of the rising height of water in the measurement sample, the water in which the measurement sample is immersed may be colored with a dye such as Blue No. 1 or methylene blue. The measurement is performed three times, and the average value is taken as the Klem water absorption height of the sheet. The measurement environment is a room temperature of 22 ± 2 ° C. and a humidity of 65 ± 2% RH.

From the viewpoint of shortening the transpiration time of absorbed sweat, the air permeability of the sweat absorbent sheet according to the present invention is preferably 300 cc / (cm ² · sec) or more, more preferably 500 cc / (cm ² · sec) or more. And preferably 2,000 cc / (cm ² · sec) or less, more preferably 1000 cc / (cm ² · sec) or less. A large value of air permeability means that the time required for passage of air, water vapor or the like is short and the air permeability is high. Conversely, if the value of the air permeability is small, it means that the air permeability is low. The air permeability can be adjusted by adjusting the density of the sweat-absorbent sheet, the distance between the constituent fibers. In general, when the density of the sweat-absorbent sheet decreases or the distance between the constituent fibers increases, the value of the air permeability increases and the breathability of the sweat-absorbent sheet improves. The air permeability is measured by the following method.

<Measurement method of air permeability>
The air permeability is obtained by taking out a constituent member (for example, a sweat-absorbing sheet) from the absorbent article, and reducing the ventilation resistance (unit: m / (kPa · s)) with AUTOMATIC AIR-PERMEABILITY TESTER KES-F8-AP1 manufactured by Kato Tech Co., Ltd. The air permeability (unit: cc / (cm ² · sec)) can be obtained by measuring and multiplying the reciprocal of the airflow resistance by 12.5. The measurement is performed three times, and the average value is taken as the air permeability of the sheet.

  The sweat-absorbent sheet according to the present invention can be produced by attaching a hydrophilizing agent to a nonwoven fabric (base nonwoven fabric) made of fibers containing a hydrophobic resin. The method for attaching the hydrophilizing agent to the base non-woven fabric is not particularly limited as long as the hydrophilizing agent can be partially attached to the base non-woven fabric, and examples thereof include application or spraying of a coating liquid containing the hydrophilizing agent. It is done. Specifically, gravure coating, flexographic coating, and pattern spray coating by intermittently flowing air using a plurality of nozzles are preferable. A flexo coat is particularly preferable in that the diffusion of the hydrophilizing agent in the thickness direction of the nonwoven fabric is controlled and the area ratio of the hydrophilic part on the coated surface side of the hydrophilizing agent can be made larger than that on the non-coated surface side.

  For example, as a method for producing a sweat-absorbent sheet such as the sweat-absorbent sheet 10 in which the skin facing surface side surface layer part has a smaller hydrophilic area ratio than the non-skin facing surface side surface layer part, There is a method in which the adhesion amount of the hydrophilizing agent is different between the surface and the other surface. This method includes a mode in which the hydrophilic agent is applied from one surface of the base nonwoven fabric and the hydrophilic agent is not applied from the other surface. For example, in the case of such an embodiment, the hydrophilizing agent applied to one surface of the base non-woven fabric usually penetrates the base non-woven fabric in the thickness direction and reaches the other surface, but the other surface, that is, the non-coating liquid is not applied. Since the area of the hydrophilic part adhering to the imparting surface, that is, the area of the hydrophilic part is smaller than the area of the hydrophilic part on one side of the hydrophilic agent imparting surface, the area ratio of the hydrophilic part between both surfaces of the base nonwoven fabric There will be a difference. Therefore, the surface to which the hydrophilizing agent is applied or the surface on which the hydrophilizing agent is relatively attached is the non-skin facing surface having a relatively large hydrophilic area ratio, and the surface opposite to the applying surface (hydrophilization) It is preferable that the non-application surface of the agent or the surface with a relatively small amount of hydrophilic agent attached) be a skin-facing surface with a relatively small hydrophilic area ratio.

  Attachment of the hydrophilizing agent to the base nonwoven fabric can be performed during the manufacturing process of the absorbent article. For example, in the diaper 1A, a constituent member of the absorbent article (for example, the folded portion 31E of the inner layer sheet 32 and the outer layer sheet 31) disposed in the surface material non-existing region N is a base nonwoven fabric, and this base is included in the production line of the diaper 1A. It is preferable to apply a hydrophilizing agent to a constituent member that is a non-woven fabric because the hydrophilizing agent is not wound around a roll once after application and there is no transfer of the hydrophilizing agent from the coated surface to the non-coated surface. In addition, for example, it is preferable not to apply a hydrophilizing agent to the portion where the leak-proof cuff 24 and the inner layer sheet 32 are joined in terms of preventing excrement from leaking out. Since the hydrophilizing agent can be intermittently applied to a necessary portion as long as it is applied, the application of the hydrophilizing agent to a site where application of such a hydrophilizing agent is not desirable can be easily avoided.

  The adhesion amount of the hydrophilizing agent in the sweat-absorbent sheet according to the present invention is preferably in terms of solid content with respect to the total mass of the sweat-absorbent sheet, from the viewpoint of setting the water pressure resistance of the sweat-absorbent sheet in the above preferred range, 0.05 mass% or more, more preferably 0.1 mass% or more, and preferably 10 mass% or less, more preferably 2.0 mass% or less.

  In addition, as a method of attaching the hydrophilizing agent to the base nonwoven fabric, a method of applying a coating solution prepared by dissolving the hydrophilizing agent in an appropriate solvent (for example, water or an organic solvent) is usually employed. If the concentration of the liquid is too low, when the coating liquid is applied to the base nonwoven fabric, the coating liquid excessively wets and spreads due to the capillary action of the constituent fibers. There is a risk of lowering. Considering the above, the concentration of the hydrophilizing agent in the coating solution is preferably 3.0% by mass or more, more preferably 5.0% by mass or more, and preferably 100% with respect to the total mass of the coating solution. It is not more than mass%, more preferably not more than 60 mass%.

  The sweat-absorbent sheet according to the present invention includes a sheet having irregularities on the surface in addition to a flat sheet having substantially no irregularities on the surface, such as the sweat-absorbent sheet 10 shown in FIG. The surface of the sweat-absorbent sheet may have unevenness, but it is preferable that unevenness is present on the skin-facing surface from the viewpoint of improving the touch and dryness. Moreover, in that case, it is preferable that the convex part which forms an unevenness | corrugation, ie, the convex part which protrudes toward a wearer's skin side, is a hydrophobic part, and a recessed part is a hydrophilic part.

The material for forming the sweat-absorbent sheet according to the present invention will be described. As the “nonwoven fabric made of fibers containing a hydrophobic resin” (base nonwoven fabric) to which a hydrophilizing agent is attached, nonwoven fabrics produced by various production methods can be used without particular limitation. Specific examples include non-woven fabrics manufactured by the card method, spunbonded non-woven fabrics (including those obtained by laminating meltblown layers), air-through non-woven fabrics, melt-blown non-woven fabrics, spunlace non-woven fabrics, and needle punched non-woven fabrics. In particular, a spunbonded nonwoven fabric is preferable from the viewpoints of touch, tensile strength, productivity, and the like. The basis weight of the base nonwoven fabric may be appropriately adjusted according to the arrangement position of the sweat-absorbent sheet and is not particularly limited, but is preferably 3 g / m ² or more, more preferably 5 g / m ² or more, and preferably 25 g. / M ² or less, more preferably 15 g / m ² or less. Furthermore, 9 g / m ² or less is preferable from the standpoint that a synergistic effect is obtained because air permeability is increased and sweat transpiration is improved.

The fiber containing the hydrophobic resin used in the sweat-absorbent sheet according to the present invention does not contain a hydrophilizing agent such as a surfactant, and at least before the attachment of the hydrophilizing agent for forming a hydrophilic portion, It is a fiber that has not been subjected to a hydrophilization treatment such as a treatment with a chemical agent or a plasma treatment, that is, an inherently hydrophobic fiber. As the fiber containing the hydrophobic resin, fibers (heat-bonded fibers) made of various thermoplastic resins can be used. Examples of the thermoplastic resin include polyolefins such as polyethylene and polypropylene; polyethylene copolymers containing α-olefins such as propylene; polypropylene copolymers containing ethylene and α-olefins; polyesters such as polyethylene terephthalate; polyamides such as nylon 6 and nylon 66; Acrylic acid, polymethacrylic acid alkyl ester, polyvinyl chloride, polyvinylidene chloride and the like can be mentioned, and one of these can be used alone or in combination of two or more. The fiber containing the hydrophobic resin may be a short fiber or a long fiber. As the fiber containing the hydrophobic resin, a core-sheath type or side-by-side type composite fiber or crimped fiber, split fiber, modified cross-section fiber, heat-shrinkable fiber, or the like can be used. The content rate of the fiber containing the hydrophobic resin in the base nonwoven fabric of the sweat-absorbent sheet according to the present invention is at least 50% by mass, and is basically basically 100% by mass.
Further, in order to obtain a sweat-absorbent sheet having a good touch and concealment like underwear, homopolypropylene is contained in an amount of 70 to 90% by mass, and ethylene as a flexibility improver is contained in an amount of 5 to 15% by mass ( (Ethylene is randomly or block copolymerized) 10% to 30% by weight of a polypropylene copolymer, 0.3% to 3% by weight of erucamide as a slipping improver, and titanium oxide as a hiding improver It is preferable to use for the base nonwoven fabric a nonwoven fabric composed of fibers mixed with 0.3 mass% or more and 2 mass% or less.

Examples of the hydrophilizing agent used in the sweat-absorbent sheet according to the present invention include the following.
-Ether type nonionic surfactants such as polyoxyethylene alkyl ether, polyoxypropylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxypropylene alkyl phenyl ether and the like.
-Polyhydric alcohol ether type nonionic surfactants such as alkyl glycosides.
-Ester-type nonionic surfactants such as polyethylene glycol esters, polyoxyethylene fatty acid esters, polyoxypropylene fatty acid esters and the like.
-Polyhydric alcohol ester type nonionic surfactants such as sucrose fatty acid ester, sorbitan fatty acid ester, polyoxyethylene fatty acid ester, polyoxypropylene fatty acid ester.
Amide-based nonionic surfactants such as fatty acid alkanolamides and alkylene oxide adducts of aliphatic amides having an acyl group having 8 to 18 carbon atoms.
Alkyl ethoxylates, polyethylene glycol dilaurate, polyethylene glycol distearate, alkyl ethoxylated amines.
・ Dimethylsiloxane ・ methyl (polyoxyethylene) siloxane copolymer, dimethylsiloxane ・ methyl (polyoxypropylene) siloxane copolymer, dimethylsiloxane ・ methyl (polyoxyethylene / polyoxypropylene) siloxane copolymer, methyl (poly Oxyethylene) polysiloxane copolymer, methyl (polyoxypropylene) polysiloxane copolymer, methyl (polyoxyethylene / polyoxypropylene) polysiloxane copolymer, methyl (polyoxyethylene / polyoxybutylene) polysiloxane copolymer Polyoxyalkylene-modified silicone such as a polymer.

  Preferred examples of the polyoxyalkylene-modified silicone include those represented by the following general formula (I).

  In the general formula (I), “Me” represents a methyl group, “R” represents a methylene group, a propylene group, a butylene group, an N- (aminoethyl) methylimino group, an N- (aminopropyl) propylimino group, or the like. , “X” represents a polyoxyalkylene group, “m” and “n” represent an integer in which each repeating unit is repeated. Examples of the polyoxyalkylene group include a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, and a copolymer of these constituent monomers.

  The polyoxyalkylene-modified silicone preferably has an HLB (hydrophilic-lipophilic balance) of 5 or more, particularly 6 or more, particularly 7 or more. As a result, the polyoxyalkylene-modified silicone can easily increase the hydrophilicity of the fiber by acting as the polyoxyalkylene group. Further, the HLB of the polyoxyalkylene-modified silicone is preferably 16 or less, particularly 15.5 or less, particularly 15 or less, from the viewpoint of leaving the polyoxyalkylene-modified silicone on the fiber surface during various processing.

  The polyoxyalkylene-modified silicone preferably has one or both modified groups of polyoxyethylene (POE) modification and polyoxypropylene (POP) modification. Although it does not restrict | limit especially as what has this modification group, For example, there exists a thing of the paragraphs [0006] and [0012] of Unexamined-Japanese-Patent No. 2002-161474. That is, the polyoxyalkylene group includes a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, and the like, and in particular, polyoxyethylene alone or a random or block copolymer of polyoxyethylene and polyoxypropylene is preferable. The number of added moles is preferably 2 to 20 moles, more preferably 5 to 15 moles. The polyoxyethylene to be copolymerized is preferably equimolar with or higher than polyoxypropylene. The number of added moles of polyoxyethylene is more preferably 10 moles or more from the viewpoint of ensuring water solubility.

  Moreover, it is preferable that Si content rate in the said polyoxyalkylene modified silicone is 20 to 70 mass%. If the Si content is too low, sufficient hydrophilic performance may not be obtained. If the Si content is too high, the stability of the product may be poor and the cost may be increased.

  Specific examples of the polyoxyalkylene group are as described above, but it is preferable to contain at least 20% by weight of the polyoxyethylene part with respect to the polyoxyalkylene. If the content of the polyoxyethylene part in the polyoxyalkylene group is too small, sufficient hydrophilic performance and water solubility may not be obtained.

  The polyoxyalkylene-modified silicone preferably has a weight average molecular weight of 1000 or more and 10,000 or less. Outside this range, the hydrophilicity decreases, and this tendency is particularly remarkable when the weight average molecular weight is less than 1000.

  Specific examples of the polyoxyalkylene-modified silicone include polyoxyethylene (POE) polyoxypropylene (POP) -modified silicone and polyoxyethylene (POE) -modified silicone.

  The hydrophilizing agent used in the sweat-absorbent sheet according to the present invention is preferably water-insoluble. By using a water-insoluble hydrophilizing agent, it becomes difficult for the hydrophilizing agent to bleed or flow when the sweat-absorbent sheet comes into contact with body fluid such as sweat or urine while wearing the absorbent article. The water-insoluble hydrophilizing agent means one having a solubility in water of 25 ° C. measured by the following method of 1% by mass or less. The water-insoluble hydrophilizing agent can be obtained, for example, by a method of setting the weight average molecular weight of the hydrophilizing agent to 3000 or more, or increasing the chain length of the alkyl chain of the hydrophilizing agent. Examples of the water-insoluble hydrophilizing agent include polyoxyethylene lauryl ether.

<Measurement method of solubility of hydrophilizing agent>
A hydrophilizing agent is added to 100 g of deionized water at 25 ° C. and dissolved by stirring with a stirrer or a shaker. The solubility in water at 25 ° C.

  In the absorbent article of the present invention, as described above, the sweat-absorbent sheet is disposed in a surface material non-existing region that does not overlap the surface material when the absorbent article is developed and projected in the thickness direction. The sweat-absorbent sheet may be disposed at least in the surface material non-existing region, and may be disposed in a region other than the surface material non-existing region, that is, a region overlapping the surface material in plan view.

  In the diaper 1A, the surface material non-existing region N where the sweat-absorbent sheet is disposed is a hatched portion in FIG. The sweat-absorbent sheet may be disposed over the entire surface material non-existing region N, or may be disposed only in a part of the surface material non-existing region N. As an arrangement | positioning site | part of a hygroscopic sheet | seat, a waist part D and the trunk periphery E are mentioned with reference to FIG. The waist part D is a part located around the waist of the wearer, and is usually the length of the longitudinal direction X of the diaper 1A from the end in the longitudinal direction X on the abdominal side A side or the back side part C side of the diaper 1A. It is an area up to a length of 1 to 15%. The waistline portion E is a region located between the waist portion D and the crotch portion B of each of the abdominal side portion A and the back side portion C.

  In the absorbent article of the present invention, from the viewpoint of fully utilizing the function of the sweat-absorbent sheet, the sweat-absorbent sheet is (i) disposed closest to the wearer's skin in the surface material absence region, or ( ii) It is arranged so as to overlap the non-skin facing surface of the hydrophilic non-woven fabric arranged closest to the wearer's skin in the surface material non-existing region. As the hydrophilic non-woven fabric (ii), non-woven fabrics produced by various manufacturing methods can be used without particular limitation on the premise that the hydrophilic fiber is used as a constituent fiber. For example, the hydrophilic non-woven fabric serves as a base for the sweat-absorbent sheet according to the present invention. A nonwoven fabric similar to the nonwoven fabric can be used. Further, as the hydrophilic fiber, a fiber containing a hydrophobic resin subjected to a hydrophilization treatment, specifically, for example, a fiber containing a hydrophobic resin kneaded with a hydrophilic agent, and a hydrophilic agent attached to the surface The fibers containing the hydrophobic resin can be used, and further, fibers that are inherently hydrophilic, for example, natural or semi-natural fibers such as cellulose fibers can be used. As the hydrophilic non-woven fabric of (ii), treatment with a hydrophilizing agent, plasma treatment on the whole of the “non-woven fabric made of fibers containing a hydrophobic resin”, which is the non-woven fabric that is the base of the sweat-absorbent sheet according to the present invention. What gave the hydrophilization process of these etc. can also be used. This sweat-absorbing sheet is disposed closest to the wearer's skin in the surface material non-existing region of (i) as compared to the layer of (ii) hydrophilic non-woven fabric superimposed on the non-skin facing surface. It is more preferable that sweat is not left on the surface of the nonwoven fabric on the skin side, and diffusion and transpiration to the non-skin surface are efficiently performed.

  In the absorbent article of the present invention, one or more nonwoven fabrics may be arranged on the non-skin facing surface of the sweat-absorbent sheet, and in that case, at least one of the nonwoven fabrics is preferably a hydrophobic nonwoven fabric. . As this hydrophobic non-woven fabric, a non-woven fabric consisting only of the hydrophobic part, that is, a non-woven fabric consisting only of a region where the contact angle of the fiber measured by the above method is 100 degrees or more can be used. A “nonwoven fabric made of fibers containing a hydrophobic resin” which is a non-woven fabric can be used as it is. With such a sweat-absorbing sheet configuration, the leak-proof property is further improved, and in particular, body fluids are effectively suppressed from leaking through the sweat-absorbing sheet in the thickness direction.

  In the absorbent article of the present invention, the basic constituent member necessary for forming a body as the absorbent article may be a sweat-absorbent sheet. For example, in the diaper 1A, the exterior body 3 disposed in the waist part D and / or the waistline part E may be a sweat-absorbing sheet, and more specifically, for example, the folded part 31E of the outer layer sheet 31 or the inner layer sheet 32. May be a sweat-absorbing sheet.

  Further, in the absorbent article of the present invention, a sheet material separate from the basic constituent members of the absorbent article such as the absorbent main body 2 and the exterior body 3 (the outer layer sheet 31 and the inner layer sheet 32) as the sweat absorbing sheet. (Barrier sheet) may be used. For example, in the diaper 1A, the sweat-absorbent sheet as the barrier sheet is located at the waist part D and / or the waist part E of at least one of the abdominal side A and the back side C and is located closest to the skin of the wearer. It can arrange | position so that it may extend in the direction Y, More specifically, it can arrange | position in the same position as the folding | returning part 31E (refer FIG. 2) of the outer layer sheet | seat 31. FIG.

In the diaper 1 </ b> A, when the sweat-absorbent sheet is disposed on the exterior body 3 of the waistline E, preferable forms of the exterior body 3 include the following 1) and 2). The forms 1) and 2) below are both excellent in leak-proofing properties and hardly cause leakage of body fluids such as urine. Particularly, in the form 1) below, sweat is absorbed by the sweat-absorbent sheet and stickiness is less likely to occur.
1) The outer layer sheet 31 is a hydrophobic nonwoven fabric, the inner layer sheet 32 is a sweat absorbent sheet according to the present invention, and the inner layer sheet 32 as the sweat absorbent sheet comprises a skin facing surface side surface layer portion and a non-skin facing surface side surface layer portion. And the same hydrophilicity (area ratio of hydrophilic part).
2) Any one of the outer layer sheet 31 and the inner layer sheet 32 is the sweat-absorbent sheet according to the present invention. In particular, it is preferable that the inner layer sheet 32 is a sweat-absorbent sheet according to the present invention because the effect of directly contacting the skin and sucking sweat is large, and the skin contact area of the absorbent article is also large. Furthermore, the sweat-absorbing sheet (preferably the inner layer sheet 32) is such that the surface area on the skin facing surface side has a smaller area ratio of the hydrophilic portion than the surface layer on the non-skin facing surface side.

Further, in the diaper 1A, when the sweat-absorbent sheet is disposed on the exterior body 3 of the waist portion D, preferable forms of the exterior body 3 include the following 3) and 4). In the forms 3) and 4) below, sweat is absorbed by the sweat-absorbent sheet, and stickiness is less likely to occur, and leakage is excellent, and body fluids such as urine are less likely to leak.
3) It has the folding | returning part 31E of the outer layer sheet 31, the inner layer sheet 32, and the outer layer sheet 31 in the order close | similar to a wearer's skin, the outer layer sheet 31 is the sweat absorbing sheet which concerns on this invention, and the inner layer sheet 32 is a hydrophobic nonwoven fabric. The outer layer sheet 31 as the sweat-absorbent sheet has a larger surface area ratio on the skin facing surface side surface portion than the non-skin facing surface side surface layer portion, and therefore, the folded portion 31E of the outer layer sheet 31. However, on the contrary, the skin facing surface side surface layer portion has a smaller hydrophilic area ratio than the non-skin facing surface side surface layer portion.
4) A folded portion (not shown) in which the inner layer sheet 32 extends from the edge in the longitudinal direction X of the outer layer sheet 31 to the ventral side portion A and the back side portion C and is folded back to the non-skin facing surface side of the outer layer sheet 31. The inner layer sheet 32, the outer layer sheet 31, and the inner layer sheet 32 are folded back (not shown) in the order close to the wearer's skin, and the inner layer sheet 32 is the sweat-absorbent sheet and outer layer sheet according to the present invention. 31 is a hydrophobic non-woven fabric, and the inner layer sheet 32 as the sweat-absorbent sheet has a smaller area ratio of hydrophilic part in the skin facing surface side surface layer part than in the non-skin facing surface side surface layer part. On the contrary, the folded portion (not shown) of the inner layer sheet 32 is such that the skin facing surface side surface layer portion has a larger hydrophilic portion area ratio than the non-skin facing surface side surface layer portion.

  Regarding the above 4), as the outer layer sheet 31 and the inner layer sheet 32, a non-stretchable or stretchable nonwoven fabric can be used, respectively. When stretchable nonwoven fabric is used for the sweat-absorbent sheet, it is possible to apply the hydrophilic agent after the stretch imparting process (stretching process). It is preferable at the point which can prevent that adheres. As a preferable form of 4), the ventral outer layer sheet 31A and the back outer layer sheet 31C are each a stretchable nonwoven fabric, the inner layer sheet 32 and the crotch outer layer sheet 31B are each a non-stretchable nonwoven fabric, and the inner layer sheet 32 is in the present invention. The form which is the sweat-absorbing sheet which concerns is mentioned. Such a preferred form is less conspicuous in gathers, and can have both an appearance closer to underwear and a sweat-absorbing property close to underwear.

Moreover, in 1 A of diapers, when a sweat absorbing sheet is the said barrier sheet (waist barrier sheet) distribute | arranged to the waist part D, the following 5) is mentioned as a preferable form of the waist barrier sheet. In the form of 5) below, since the area ratio of the hydrophilic portion is small, sweat hardly remains on the skin-facing surface and stickiness does not easily occur.
5) It is arranged closest to the skin of the wearer at the waist part D and / or the waistline part E of at least one of the ventral part A and the dorsal part C, and the skin facing surface side surface layer part is on the non-skin facing surface side. The hydrophilic part area ratio is smaller than the surface layer part. The waist barrier sheet has, for example, a shape that is long in one direction in plan view, specifically a rectangular shape, and the longitudinal direction of the waist barrier sheet coincides with the lateral direction Y, so that the skin of the wearer in the waist portion D and / or the waist portion E It is distribute | arranged over the full length of the horizontal direction Y of the diaper 1A in the position which can form the outermost surface of the inner surface side (skin opposing surface side) of the diaper 1A.

  The absorbent article of the present invention may be colored. Since ordinary absorbent articles are white, the absorbent article of the present invention may have a color other than white. When the absorbent article has a color other than white, depending on the color, a texture or impression that cannot be obtained with white, for example, a refreshing feeling, can be obtained. The light transmittance of the underwear is usually about 5 to 40%, whereas the light transmittance of a normal white absorbent article that is not colored is about 47 to 70%. Compared with underwear, it is inferior in the concealment of absorbed body fluid, and if it is an absorbent article having a color other than white, it can have the same light transmittance as underwear, and the appearance is underwear It can be something like that. The light transmittance referred to here can be measured using NDH5000 manufactured by Nippon Denshoku Industries in accordance with JISK7361-1, and can be measured at any of five measurement sites on a measurement object such as an absorbent article. It is obtained as an average value of light transmittance. Coloring may be applied to the entire absorbent article, or may be applied to only a part of the constituent members such as the sweat-absorbent sheet and the exterior (outer layer sheet, inner layer sheet). The color to be colored is not particularly limited and can be appropriately selected from red, blue, yellow and the like. The absorbent article can be colored by adhering a colorant to the constituent member of the absorbent article to be colored according to a known printing method.

  When coloring a sweat-absorbent sheet, it can be colored in the manufacturing process. Specifically, for example, a base nonwoven fabric (nonwoven fabric made of fibers containing a hydrophobic resin) that is a raw material of the sweat-absorbent sheet is made hydrophilic. By applying a hydrophilic or water-repellent colorant together with the agent, a colored sweat-absorbing sheet colored in a color other than white can be produced. In that case, a colorless and transparent hydrophilizing agent may be used, or the color inherently possessed by the hydrophilizing agent may be used as it is. Further, the hydrophilic colorant and the water repellent colorant can be used in combination on the condition that the following points are noted.

  In the colored sweat-absorbent sheet, when a water-repellent colorant is used as a colorant to be applied to the base nonwoven fabric, the application part of the water-repellent colorant, that is, the colored part (water-repellent part) is the application part of the hydrophilic agent, that is, the hydrophilic part. It is preferable not to overlap. This is because if they overlap, the transpiration function such as sweat by the hydrophilic portion may be inhibited. From such a viewpoint, as a preferable example of the coloring pattern in the colored sweat-absorbent sheet, hydrophilic portions and colored portions (water-repellent portions) are alternately arranged in one direction (for example, arranged in a continuous stripe shape in one direction), A pattern in which a hydrophilic agent and a non-adhered portion of the coloring agent are located between the hydrophilic portion and the colored portion adjacent to each other in the one direction is exemplified. Further, as another pattern, the hydrophilic portion has a closed shape in a plan view as shown in FIG. 5A, the colored portion surrounds the hydrophilic portion, and the hydrophilic portion and the colored portion surrounding the hydrophilic portion. A pattern in which a non-adhered portion of a hydrophilizing agent and a colorant is located is included. In addition, when the hydrophilic agent and the water-repellent colorant applied to the base nonwoven fabric that is the raw material of the sweat-absorbent sheet each contain a solvent, the applied agent is dried both during and after application of each agent. It is preferable to carry out. Thereby, the hydrophilizing agent and the water repellent colorant are not mixed on the base nonwoven fabric and are easily formed into independent layers, and the overlap between the hydrophilic portion and the colored portion (water repellent portion) can be effectively prevented.

  On the other hand, in the colored sweat-absorbent sheet, when a hydrophilic colorant is used as a colorant to be applied to the base nonwoven fabric, there is no particular problem even if the colored portion that is the application site overlaps with the application site of the hydrophilizing agent. . Therefore, in this case, the colored sweat-absorbent sheet can be produced by a method of applying a mixture of a hydrophilizing agent and a hydrophilic colorant to a base non-woven fabric. Improvement in adhesion stability can be expected, and the process can be simplified. In particular, in this method, since a mixture of a hydrophilizing agent and a hydrophilic colorant is applied, the fiber surface of the colored portion, which is the application site of the mixture, becomes hydrophilic, which is good in terms of absorption and transpiration of sweat and the like. It becomes. In preparing this mixture, the concentration of the hydrophilizing agent relative to the hydrophilic colorant is 2 to 20% by mass, adjustment of the bleed amount of the hydrophilizing agent in the hydrophilic colorant, adhesion of the hydrophilic colorant to the nonwoven fabric From the viewpoint of maintaining the property. When multicolor printing is performed using a plurality of colorants, it is preferable to use a hydrophilic colorant for at least one of the plurality of colorants.

  As a method for applying the mixture of the hydrophilizing agent and the hydrophilic colorant to the base nonwoven fabric, flexographic printing (flexographic coating method) is preferable. Flexographic printing has the advantage that positional displacement of each color can be suppressed because the nonwoven fabric can be fixed by friction with the nonwoven fabric to be colored on the cylinder drum. When color misregistration occurs, colors overlap on the nonwoven fabric, and a water-repellent colorant that does not contain a hydrophilic agent may be applied onto a hydrophilic colorant that contains a hydrophilic agent. There is a risk that it may not be possible.

  The absorbent article of the present invention is not limited to a pants-type disposable diaper such as the diaper 1A, and may be a deployable disposable diaper as shown in FIGS. 7 and 8, for example. Regarding the unfolded disposable diaper described later, components different from the above-described pants-type disposable diaper 1A will be mainly described, and the same components will be denoted by the same reference numerals and description thereof will be omitted. The explanation about the diaper 1 </ b> A is appropriately applied to components that are not particularly described.

  7 and 8 show a deployable disposable diaper 1B which is another embodiment of the absorbent article of the present invention. As shown in FIG. 8, the diaper 1 </ b> B includes a liquid-retaining absorbent body 53 and a surface sheet 51 as a surface material disposed on the side closer to the wearer's skin than the absorbent body 53.

  More specifically, the diaper 1B includes a liquid-permeable surface sheet 51 that forms a skin-facing surface, a liquid-impermeable or liquid-permeable or water-repellent back sheet 52 that forms a non-skin-facing surface, and both A liquid-retaining absorbent 53 is disposed between the sheets 51 and 52, and these are integrated by a known joining means such as an adhesive. Each of the top sheet 51 and the back sheet 52 has a size larger than that of the absorber 53, and extends outward from the peripheral edge of the absorber 53. The back sheet 52 forms the outer shape of the diaper 1B in the unfolded and stretched state as shown in FIG. The absorbent body 53 includes a liquid-retaining absorbent core 531 and a core wrap sheet 532 that covers the outer surface (both skin facing surface and non-skin facing surface) of the absorbent core 531.

  Between the top sheet 51 and the back sheet 52 in each of the ventral side A and the back side C, one or a plurality of thread-like or belt-like waistline elastic members 54 are fixed in a state of extending in the lateral direction Y, and Between the top sheet 51 and the back sheet 52 in the left and right leg portions arranged around the legs of the wearer, one or a plurality of leg elastic members 55 in the form of threads or belts are fixed in an extended state. Further, a pair of leak-proof cuffs 56, 56 each comprising a liquid-resistant or water-repellent and breathable leak-proof cuff forming sheet 57 on both left and right side portions along the longitudinal direction X on the skin facing surface of the diaper 1 </ b> B. Is provided. In the vicinity of the free end portion of each leak-proof cuff 56, one or more thread-like leak-proof cuff forming elastic members 58 are arranged in an elongated state in the longitudinal direction X. As shown in FIG. 8, the leakage prevention cuff forming sheet 57 is formed on the top sheet 51 and the back sheet 52 by a known joining means such as an adhesive or fusion, outside the absorbent body 53 in the lateral direction Y. When the diaper 1 </ b> B is worn, the leak-proof cuff 56 stands up toward the wearer's skin with the joint 59 as a starting point. The joint portion 59 has a linear shape extending in the longitudinal direction X in a plan view as shown in FIG.

  As shown in FIG. 7, a pair of fastening tapes 60, 60 are provided on both side edges along the longitudinal direction X of the back side C of the diaper 1B. A fastening portion 61 made of a male member of a mechanical surface fastener is attached to the fastening tape 60. Moreover, the to-be-attached area | region 62 which consists of the female member of a mechanical hook-and-loop fastener is formed in the non-skin opposing surface of the belly side part A of the diaper 1B. The to-be-attached region 62 is formed by attaching a female member of a mechanical hook-and-loop fastener to the non-skin facing surface of the back sheet 52 that forms the non-skin facing surface of the ventral side A by a known joining means such as an adhesive or heat seal. The fastening part 61 of the fastening tape 60 can be detachably fastened.

  As the surface material non-existing region N in which the sweat-absorbent sheet is arranged in the diaper 1B, for example, a hatched portion in FIG. 7 can be exemplified. As shown in FIGS. 7 and 8, the surface material non-existing region N in the diaper 1 </ b> B is outward in the lateral direction Y from the joint portion 59. In the diaper 1 </ b> B, for example, a leak-proof cuff forming sheet 57 existing in the surface material non-existing region N, that is, a portion of the leak-proof cuff forming sheet 57 that is located outward in the lateral direction Y from the joint portion 59 Sheet.

  As mentioned above, although this invention was demonstrated based on the embodiment, this invention can be changed suitably, without being restrict | limited to the said embodiment. For example, the exterior body 3 in the pants-type disposable diaper 1A is not divided into the abdominal part A and the dorsal part C as shown in FIG. 2, and extends over the abdominal part A, the crotch part B, and the dorsal part C. Although it had a continuous shape such as an hourglass shape, the exterior body according to the present invention is not limited to such a continuous shape, and for example, an abdominal sheet placed on the abdomen side (front side) of the wearer It is divided | segmented into the member and the back | dorsal sheet | seat member distribute | arranged to a wearer's back | dorsal side (rear side), and the absorptive main body may be bridge | crossed and fixed to these both sheet | seat members. The description omitted in one embodiment described above and the requirements of only one embodiment can be applied to other embodiments as appropriate, and the requirements in each embodiment can be appropriately changed between the embodiments. Can be substituted.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to such examples.

[Example 1]
It is composed of fibers containing a hydrophobic resin in which 80% by mass of homopolypropylene, 18.5% by mass of polypropylene copolymer containing 8% by mass of ethylene, 1% by mass of erucamide, and 0.5% by mass of titanium oxide are mixed. As a non-woven fabric (base non-woven fabric), a spunbond non-woven fabric with an embossed area ratio of 11% and 3 spunbond layers laminated to a total basis weight of 16 g / m ² is used, and both sides of the base non-woven fabric are made hydrophilic by flexo coating. The surface of the non-skin facing surface 10b of the base nonwoven fabric shown in FIG. 5 (a) on the non-embossed surface side (flat roll contact surface side) of the spunbond nonwoven fabric is coated with a coating liquid containing an agent (hydrophilizing agent concentration 15% by mass). It apply | coated from the side and it apply | coated partially like a dot pattern similarly to the dot-like pattern shown to Fig.5 (a), and obtained the sweat absorbing sheet. Specifically, the dot-like pattern of the hydrophilic portion is a pattern in which the hydrophilic portions (applied portions of the hydrophilizing agent) having a rhombus shape in plan view are arranged in a staggered manner. Moreover, the convex part area ratio in the plate used for application | coating of the coating liquid by a flexo coating method is 25%, and the hydrophilic part area ratio of a to-be-coated surface substantially corresponds to this convex part area ratio. In the staggered arrangement pattern of the hydrophilic portions, the pitch P between the two hydrophilic portions (see FIG. 5B) is 1.0 mm in the MD direction and 0.8 mm in the CD direction. The gap G between the hydrophilic portions (see FIG. 5B) was 0.35 mm at the shortest portion of the gap G. Water-insoluble polyoxyethylene lauryl ether was used as the hydrophilizing agent, and a mixed solvent of ethyl acetate, butyl acetate and isopropyl alcohol was used as the coating solution. The coating amount of the hydrophilizing agent was determined as the amount with respect to the nonwoven fabric, and is shown in the table as the total adhesion amount. The coating amount was adjusted using an anilox roll for transferring the coating solution to the relief roll using # 240 (number of lines / inch). The coating amount of the hydrophilic agent per one side of the base nonwoven fabric was higher on the coated surface side of the hydrophilic agent than on the non-coated surface. In the obtained sweat-absorbent sheet, the application surface of the hydrophilizing agent is a non-skin facing surface with a relatively large hydrophilic area ratio, and the non-application surface of the hydrophilizing agent is a skin with a relatively small hydrophilic area area ratio. It was set as the opposing surface.

[Example 2]
The anilox roll was changed to # 400 (number of lines / inch), and a sweat-absorbing sheet was obtained in the same manner as in Example 1.

Example 3
An anilox roll was changed to # 160 (number of lines / inch) with a hydrophilizing agent concentration of 4 mass%, and a sweat-absorbent sheet was obtained in the same manner as in Example 1.

Example 4
The hydrophobizing agent was changed from water-insoluble polyoxyethylene lauryl ether to water-soluble polyoxyethylene alkyl ether, and the concentration of the hydrophilizing agent was 25% by mass to obtain a sweat-absorbing sheet in the same manner as in Example 1.

Example 5
A sweat-absorbing sheet was obtained in the same manner as in Example 1 except that a hydrophilic colorant containing a water repellent colorant and a hydrophilic agent was applied to the base nonwoven fabric. The composition of the colorant is as follows.
Indigo phthalocyanine pigment: 30% by mass
-Polyurethane resin: 60% by mass
・ Hydrophilic agent: 10% by mass
-Mixed solvent of ethyl acetate, butyl acetate and isopropyl alcohol: added so that the concentration of the above components is 35%

[Comparative Example 1]
A hydrophilic agent was not applied to the base nonwoven fabric, and the base nonwoven fabric was used as it was as a sweat-absorbing sheet.

〔Evaluation test〕
For the sweat-absorbent sheets of each Example and Comparative Example, droplet evaluation, water pressure resistance, and Klem water absorption height were measured by the above methods. The results are shown in Table 1 below.

In Comparative Example 1, a hydrophobic nonwoven fabric not coated with a hydrophilizing agent is used as it is as a sweat-absorbent sheet. As shown in Table 1, the water pressure resistance is as high as 50 mm, and the leakage resistance is excellent. In the evaluation, the deionized water droplets did not penetrate, and the sweat absorption was superior in the examples.
On the other hand, each example has a structure in which a hydrophilizing agent is partially attached to the hydrophobic nonwoven fabric of Comparative Example 1, and has a partial hydrophilicity, and as a result, droplets In the evaluation, it has excellent sweat absorbency that allows 4 or more drops of deionized water to permeate, and with respect to leakage resistance, the water pressure resistance is 10 mm or more (the larger the water pressure resistance value, the higher the water leakage resistance). Excellent), Klem water absorption height is 1 mm (the smaller the Klem water absorption value, the better the leakage prevention), so it is also excellent in leakage prevention, leakage due to penetration of body fluid in the thickness direction, and body fluid sheet Leakage (lateral leakage) due to flowing on the surface could be effectively prevented.
Further, from comparison between Example 1 and Example 4, it is found that when a water-insoluble one as a hydrophilizing agent is used as in Example 1, the sweat absorption and water pressure resistance are improved.
Further, from the comparison between Example 1 and Example 3, as in Example 1, the hydrophilicity (hydrophilic area ratio) of the skin facing surface side surface layer portion is lower than that of the non-skin facing surface side surface layer portion. It can be seen that the water pressure resistance is particularly improved.
Further, from the comparison between Example 1 and Example 5, even when a coloring agent is used in combination with a hydrophilizing agent and an intermittent coloring pattern is imparted to the sweat-absorbing sheet, sweat-absorbing properties (droplet evaluation results) and leak-proof properties It can be seen that there is substantially no influence on the (water pressure resistance and evaluation results of the water absorption height of the clem), and it is possible to improve both characteristics.

1A Pants-type disposable diaper (absorbent article)
2 Absorbent body 21 Surface sheet (surface material)
22 Back sheet 23 Absorber 24 Leak-proof cuff 3 Exterior body 31 Outer layer sheet 31E Folded part of outer layer sheet 32 Inner layer sheet 1B Unfoldable disposable diaper (absorbent article)
51 Surface sheet (surface material)
52 Back sheet 53 Absorber 56 Leak-proof cuff 10, 90 Sweat-absorbing sheet 11, 92 Hydrophilic part 12, 91 Hydrophobic part A Abdominal side B Crotch part C Back side part D Waist part E Trunk circumference part N Surface material non-existing area (Arrangement area of sweat-absorbing sheet)
X Vertical direction Y Horizontal direction

Claims (7)

An absorbent article comprising a liquid-retaining absorbent and a surface material disposed closer to the wearer's skin than the absorbent,
When the absorbent article is developed and projected in the thickness direction, the absorbent material is disposed in a surface material non-existing region that does not overlap with the surface material, and the sweat absorbent sheet is disposed in the surface material non-existing region. , Arranged closest to the skin of the wearer, or overlaid on the non-skin facing surface of the hydrophilic non-woven fabric arranged closest to the skin of the wearer,
The sweat-absorbent sheet has a configuration in which a hydrophilizing agent is partially attached to a non-woven fabric composed of fibers containing a hydrophobic resin, and is partially hydrophilic.
In the plan view of the sweat-absorbent sheet, there are a plurality of hydrophilic portions to which the hydrophilic agent is attached, and a hydrophobic portion to which the hydrophilic agent is not attached around each of the hydrophilic portions. Sex goods.   The absorptive article according to claim 1 in which hydrophilicity differs in a skin opposing surface side surface layer part and a non-skin opposing surface side surface layer part of the perspiration sheet.   The absorbent article according to claim 1, wherein the sweat-absorbent sheet has a lower hydrophilicity in the skin facing surface side surface layer portion than in the non-skin facing surface side surface layer portion.   The ratio of the total area of the said hydrophilic part which the said sweat-absorbing sheet occupies the whole surface area of the said skin opposing surface side surface layer part is smaller than the non-skin opposing surface side surface layer part. The absorbent article according to any one of the above.   On the skin facing surface of the sweat-absorbent sheet, the pitch between the two hydrophilic portions adjacent to each other with the hydrophobic portion interposed therebetween is 0.3 to 20 mm, and the distance between the two hydrophilic portions is 0.2 at the shortest portion. The absorbent article according to any one of claims 1 to 4, wherein the absorbent article is 10 mm.   The absorbent article according to any one of claims 1 to 5, wherein a water pressure resistance of the sweat-absorbent sheet is 5 mm or more and 40 mm or less.   The absorbent article according to any one of claims 1 to 6, wherein one or more non-woven fabrics are arranged on the non-skin facing surface of the sweat-absorbent sheet, and at least one of the non-woven fabrics is a hydrophobic non-woven fabric. .

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