JP5297777B2 - Absorbent articles - Google Patents

Description

  The present invention relates to absorbent articles such as disposable diapers, urine pads, and sanitary napkins.

  As absorbent articles, such as a disposable diaper, there exist some which were equipped with the absorber interposed between the surface sheet which forms a skin contact surface, the back sheet which forms a non-skin contact surface, and both sheets. Conventionally, a disposable diaper having such a configuration has been proposed in which a coolant that absorbs heat during melting is disposed (see Patent Documents 1 and 2). The techniques described in Patent Documents 1 and 2 are intended to make the diaper wearer recognize urination and promote diaper separation.

  In Patent Document 1, a microencapsulation material formed by wrapping a cooling sensation agent (cooling agent) in a shell as a core, a part of the skin contact surface of a diaper, for example, a skin sheet of a diaper wearer in a surface sheet or a three-dimensional gather A technique for applying to the exposed surface is described. The microencapsulated material is adapted to allow the coolant to flow out by contacting with the urine component.

  In Patent Document 2, a temperature change element formed by interposing a temperature change substance (coolant) between the permeable layer and the impermeable layer is provided on the skin contact surface of the diaper surface sheet or the surface sheet. A technique for mounting on a non-skin contact surface is described.

JP 2008-6277 A JP-T-2004-525730

  In a conventional disposable diaper, immediately after urination, urine absorbed in the absorbent body may be released as water vapor to the outside of the absorbent body, and transpiration of such urine increases the humidity in the diaper, causing stuffiness or skin There was a problem of causing trouble. A technique for solving such a problem has not yet been provided.

  Accordingly, an object of the present invention is to provide an absorbent article that suppresses urine transpiration which causes stuffiness and skin trouble and is excellent in comfort.

The present invention is an absorbent article comprising a top sheet that forms a skin contact surface, a back sheet that forms a non-skin contact surface, and an absorbent body interposed between both sheets, the top sheet and the back surface Between the sheet, a coolant that dissolves and absorbs heat in the urine excreted by the wearer is disposed, and the surface sheet has a thickness of not less than 0.3 mm and a basis weight of not more than 50 g / m ² at a load of 3.5 kPa. The above object is achieved by providing an absorbent article formed from a bulky nonwoven fabric.

  ADVANTAGE OF THE INVENTION According to this invention, the urinary transpiration which becomes a stuffiness and skin trouble is suppressed, and the absorbent article excellent in comfort can be provided.

  Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings. FIG. 1 is a plan view of a skin contact surface side (surface sheet side) schematically showing a state (expanded state) in which the disposable diaper according to the first embodiment of the present invention is expanded in a flat shape by stretching the elastic members of each part. FIG. 2 is a cross-sectional view schematically showing a cross section taken along line XX of FIG.

  The diaper 1 of 1st Embodiment is the liquid-permeable surface sheet 2 which forms a skin contact surface, and the liquid-impermeable back sheet 3 which forms a non-skin contact surface, as shown in FIG.1 and FIG.2. , And a liquid-retaining absorbent body 4 disposed between the two sheets 2 and 3, and is of a development type that is formed substantially vertically. The diaper 1 has the back side part A, the abdominal side part B, and the crotch part C located between these in the longitudinal direction. The back side part A is a part located on the wearer's back side, the abdomen part B is a part located on the wearer's belly side, and the crotch part C is a part located on the wearer's crotch. The crotch part C is located at the center in the longitudinal direction of the diaper 1. In addition, in this specification, a skin contact surface is a surface turned to a wearer's skin side at the time of wear in an absorbent article and its structural member, and a non-skin contact surface in an absorbent article and its structural member It is a surface that is directed to the side opposite to the wearer's skin when worn.

  The diaper 1 has an hourglass shape in which both side edges along the longitudinal direction of the crotch portion C are curved inwardly in an arc shape, and the central portion in the longitudinal direction is bound inward as a whole. The top sheet 2 has a substantially rectangular planar view shape having an outer dimension larger than that of the absorber 4, and is arranged in the center in the width direction of the back sheet 3. The back sheet 3 has an hourglass-like outer shape that matches the outer shape of the diaper. The top sheet 2 and the back sheet 3 respectively extend outward from both longitudinal edge portions and both lateral edge portions of the absorbent body 4, and directly or other members are interposed in these extending portions. Are joined together by a joining means such as an adhesive or a seal joint.

  The absorbent body 4 has a rectangular shape in plan view, and is arranged in a substantially central portion of the diaper 1 with its longitudinal direction coinciding with the longitudinal direction of the diaper 1. The absorbent body 4 has a form in which the liquid-retaining absorbent core itself or the absorbent core is wrapped with a liquid-permeable core wrap sheet. The absorbent core is mainly composed of hydrophilic fibers such as pulp fibers, and preferably contains particulate water-absorbing resin. The core wrap sheet is usually disposed so as to cover the entire area of the absorbent core on the skin contact surface side and the non-skin contact surface side. The core wrap sheet and the absorbent core are joined by a joining means such as a hot-melt adhesive at a predetermined site.

  As shown in FIG. 2, a coolant 5 that dissolves and absorbs heat in urine excreted by the diaper wearer is disposed between the top sheet 2 and the back sheet 3. By disposing the coolant 5 between the top sheet 2 and the back sheet 3, the coolant 5 reacts with the excreted urine and absorbs heat, thereby causing urine to evaporate and eventually diapers. The rise in humidity in 1 can be suppressed, and the occurrence of stuffiness and skin troubles can be prevented. In the first embodiment, the coolant 5 is disposed between the top sheet 2 and the absorber 4.

  The coolant 5 is a particulate solid at normal temperature. In the first embodiment, the coolant 5 is uniformly dispersed on the skin contact surface (the surface facing the top sheet 2) of the absorbent body 4 at and near the urination point. Exist. The urination point is a part where the wearer's urination part is located when the diaper is worn, and is located in a part of the diaper 1 that is slightly biased toward the abdominal side A from the longitudinal center part. The coolant 5 is bonded to the non-skin contact surface (surface facing the absorber) of the top sheet 2 and / or the hot melt adhesive applied to the skin contact surface of the absorber at and near the urination point. By means, it is bonded and fixed to at least one of both surfaces.

  The coolant 5 is not particularly limited as long as it exhibits a cooling action by endothermic reaction when mixed with urine (water). For example, sodium acetate, sodium carbonate, sodium sulfate, sodium thiosulfate, sodium phosphate, etc. Salts of hydrates; inorganic salts such as ammonium nitrate, potassium nitrate, ammonium chloride, potassium chloride, sodium nitrate; urea; sugar alcohols such as xylitol, erythritol, sorbitol, lactitol, and other saccharides.

  The coolant 5 is generally in the form of particles, but other forms of coolant may be used. The shape of the granular coolant 5 is not particularly limited, and for example, an indefinite shape, a lump shape, a bowl shape, a spherical shape, a shape in which a plurality of spherical shapes are aggregated, or the like can be used. Moreover, it is preferable that the average particle diameter of the granular coolant 5 is 0.1-10000 micrometers, especially 1-100 micrometers from a viewpoint of a feeling of wear.

The basis weight (dispersion amount) of the coolant 5 is preferably set as appropriate according to the type of the coolant 5 in consideration of the amount of energy change due to the coolant 5 that affects the urine transpiration suppression effect and the wearing feeling. . Energy variation due coolant 5, from the viewpoint of balance between wearing comfort and transpiration suppression effect of urine, preferably 0.001~10.0kJ / cm ^2, more preferably 0.01~0.1kJ / cm ² It is. In order to make the energy change amount by the coolant 5 into such a range, when urea is used as the coolant 5 as an example, the basis weight (dispersion amount) is 10 to 4000 g / m ² , preferably 500 to 2000 g / m. m ² . In the first embodiment, as described above, the coolant 5 exists only at the urination point of the diaper 1 (the portion that directly receives the excreted urine) and the vicinity thereof. It may exist in the whole area of a contact surface (opposite surface with the surface sheet 2), and the basic weight of the coolant 5 in that case can be made into the said range. The amount of energy change can be measured as follows.

<Measurement method of energy change by coolant>
A coolant is dissolved in 1 kg of water at 50 ° C. by a weight corresponding to 1 m ² sprayed on the sample (basis weight of the coolant in the absorbent article), and the water temperature of the solution (water temperature after cooling) T ° C. Using this and the specific heat of water 4.2 J / K · kg, the amount of energy change due to the coolant is calculated by the following equation. Energy change amount due to coolant (kJ / cm ² ) = (50−T) / 42000

  In the diaper 1 of 1st Embodiment, in addition to the coolant 5 being arrange | positioned between the surface sheet 2 and the back surface sheet 3, the surface sheet 2 is formed from the bulky nonwoven fabric. The reason why the top sheet 2 is formed from a bulky nonwoven fabric is to make it difficult to transmit the temperature of urine cooled by the coolant 5 to the skin of the wearer. The bulky nonwoven fabric has a large number of space portions (portions where no nonwoven fabric constituent components such as fibers are present) defined by the constituent fibers of the nonwoven fabric, and the space portion occupying the entire volume of the nonwoven fabric. The ratio (space occupancy) is large. By using the bulky nonwoven fabric having such characteristics for the topsheet 2 that comes into contact with the skin of the wearer, the topsheet 2 (bulky nonwoven fabric) acts as a heat insulating layer, and the temperature of urine cooled by the coolant 5 is increased. It becomes difficult to convey to the wearer. The space occupation ratio of the bulky nonwoven fabric is preferably 80% or more, more preferably 90 to 95%. Conversely, a nonwoven fabric having a space occupancy of less than 80% is difficult to say as a bulky nonwoven fabric. The space occupancy of the nonwoven fabric is measured as follows.

<Measurement method of space occupancy of nonwoven fabric>
A rectangular parallelepiped or cubic sample of the nonwoven fabric to be measured is prepared, the volume of the sample is calculated, and this is used as the nonwoven fabric volume. In addition, when the sample is collected from the absorbent article and prepared, the nonwoven fabric volume of the sample is the length in the longitudinal direction, the length in the width direction, and the length in the thickness direction (3.5 kPa load). Equivalent to the product of the thickness of time). The sample is heated and melted at a high temperature (200 ° C.), and the melt is cooled and solidified at room temperature so that the melt does not contain air, and the volume of the solid is calculated. The fiber volume. And the space occupation rate of a nonwoven fabric is computed by following Formula. Nonwoven fabric space occupancy (%) = 100− (fiber volume / nonwoven fabric volume) × 100

  In addition, the length in the thickness direction of the sample in the method for measuring the space occupancy, that is, the thickness at the time of 3.5 kPa load is measured according to a conventional method using a KES-G5 handy compression tester (manufactured by Kato Tech Co., Ltd.). be able to. In this specification, the thickness at the time of 3.5 kPa load means the measured value by such a measuring method, unless otherwise specified. The load of 3.5 kPa is approximately equivalent to the pressure applied when the infant sits down.

The bulky nonwoven fabric preferably has a thickness of 0.3 mm or more and a basis weight of 50 g / m ² or less at a load of 3.5 kPa from the viewpoint of ensuring the above-described effects. The particularly preferred bulky nonwoven fabric preferably has a thickness at a load of 3.5 kPa of 0.3 to 10 mm, more preferably 0.5 to 3 mm, and a basis weight of preferably 15 to 50 g / m ² , more preferably 20 to 45 g. / M ² . From the viewpoint of making it difficult for the temperature of urine cooled by the coolant 5 to be transmitted to the wearer's skin, the bulky nonwoven fabric is preferably as thick as possible at a load of 3.5 kPa, but when the thickness increases, the urine becomes bulky nonwoven fabric ( The thickness is preferably within the above range.

  Examples of the bulky nonwoven fabric include an air-through nonwoven fabric and a spunlace nonwoven fabric in which the thickness and basis weight under a load of 3.5 kPa are in the above ranges, respectively. The bulky nonwoven fabric can be obtained, for example, by subjecting various nonwoven fabrics such as air-through nonwoven fabric and spunlace nonwoven fabric to stretching by a known gear stretching method or the like. As will be described later, the bulky nonwoven fabric obtained by such stretching is a concavo-convex sheet having a concavo-convex shape on its surface (three-dimensionally shaped), and is preferably used in the present invention. In particular, an uneven sheet of an air-through nonwoven fabric is preferable.

  As an example of the particularly preferable bulky nonwoven fabric, for example, an uneven sheet 20 shown in FIG. The concavo-convex sheet 20 includes a first layer 21 directed to the wearer's skin side and a second layer 22 disposed on the outer side. The first layer 21 is formed with a large number of convex portions 23 projecting toward the wearer's skin. The inside of the convex part 23 is hollow. A concave portion 24 is formed between the convex portions 23. The first layer 21 and the second layer 22 are joined in part or all of the recess 24. The joining of the two layers 21 and 22 can be appropriately selected from heat fusion, adhesive bonding, ultrasonic bonding, and the like.

  The convex part 23 has a rectangular bottom surface. Moreover, the convex part 23 is a flat rectangular parallelepiped or a truncated quadrangular pyramid with a rounded ridgeline as a whole. On the other hand, the recess 24 is also rectangular. Moreover, the convex part 23 and the recessed part 24 are arrange | positioned so that a row may be made | formed alternately and in one direction. In the uneven | corrugated sheet | seat 20 shown in FIG. 3, the convex part 23 and the recessed part 24 are alternately arrange | positioned along the X direction in the figure, and has comprised the row | line | column. The X direction coincides with the flow direction (MD) in the manufacturing process of the uneven sheet 20. The row | line | column which consists of the convex part 23 and the recessed part 24 is arrange | positioned at multiple rows over the Y direction in FIG.

  In the concavo-convex sheet 20, when paying attention to any one convex portion 23 in one row, in the left and right rows adjacent to the row, the other convex portions 23 are positioned adjacent to the one convex portion 23. Is not located. “No convex part is located adjacent to one convex part” means that when one convex part is focused, the convex part is not located at the same position in the adjacent row. I mean. In other words, in the Y direction in FIG. 3, it means that the convex portions are not arranged so that the convex portions 23 between adjacent columns are completely connected. Therefore, at a position adjacent to one convex portion 23, both a part of the convex portion 23 and a part of the joint portion (joint portion of the first layer 21 and the second layer 22 in the concave portion 24) exist. Or only the joint may exist.

  In the concavo-convex sheet 20, the concave portions 24 are arranged so as to be shifted by a half pitch in two adjacent rows. Therefore, when attention is paid to any one concave portion 24 in one row, the single concave portion 24 is a closed concave portion formed by being surrounded by the convex portion 23 in the front and rear and the left and right. That is, the recesses 24 are arranged in a staggered pattern. Accordingly, the convex portions 23 are similarly arranged in a staggered pattern. Since the convex portion 23 and the concave portion 24 are arranged in this way, when the concave-convex sheet 20 is used as the top sheet 2, the temperature of urine cooled by the coolant 5 described above is transmitted to the wearer's skin. In addition to the effect of making it difficult, the effect of lowering the contact pressure with the body and improving the feeling of wearing is achieved.

From the viewpoint of making the above-described effect more remarkable, it is preferable that the height H (see FIG. 3) of the convex portion 23 is 1 to 10 mm, particularly 3 to 6 mm. Moreover, it is preferable that the bottom part dimension P of the convex part 23 along a X direction (column direction) is 2-30 mm, It is preferable that it is especially 2-5 mm, and the bottom part dimension Q along a Y direction (direction orthogonal to a column direction) is 2-2. It is preferably 30 mm, particularly 2 to 5 mm. Moreover, it is preferable that the bottom area of the convex part 23 is 4-900 mm < ² >, especially 4-25 mm < ² >. Further, the bonding length R of the concave portions 24 in the X direction (row direction) is preferably 0.1 to 20 mm, particularly 0.5 to 5 mm, from the viewpoint of good touch and high cushion feeling.

  Moreover, in the uneven | corrugated sheet | seat 20, many elastic members (not shown) may be distribute | arranged between the 1st layer 21 and the 2nd layer 22 in the expansion | extension state. In this case, for example, each elastic member is bonded and fixed to the first layer 21 and the second layer 22 at a predetermined interval, and the convex portions 23 and the concave portions 24 are alternately arranged between the two layers 21 and 22. Are arranged in the same direction as the row (column in the X direction in FIG. 3). Further, each elastic member is disposed so as to pass through the central portion in the width direction of the convex portion 23 where the first layer 21 and the second layer 22 are not joined to each other. 22 is joined, and the convex portion 23 is not joined to both layers 21 and 22. Thus, the elastic member in the concavo-convex sheet 20 is partially bonded to the both layers 21 and 22, so that the concavo-convex sheet 20 is orthogonal to the length direction of the elastic member in a natural state (relaxed state). Regular folds are formed in the direction. Since these folds extend continuously over the width direction of the concavo-convex sheet 20, they are very beautiful in appearance. Thus, the pleat having a good appearance is formed due to the elastic member being in a non-bonded state with the first layer 21 and the second layer 22 in a portion between both end portions thereof.

  The first layer 21 and the second layer 22 constituting the concavo-convex sheet 20 are made of the same or different sheet-like materials. As this sheet-like material, a material that is substantially non-stretchable is preferable in terms of obtaining a concavo-convex shape having a desired dimension. The substantially non-stretchable sheet-like material means, for example, an elongation limit of 105% or less, and material elongation or permanent deformation occurs when the elongation limit is exceeded. As such a sheet-like material, any material that is substantially non-stretchable in materials used for conventionally known absorbent articles can be used without any particular limitation. For example, various nonwoven fabrics such as a nonwoven fabric produced by a card method, an air-through nonwoven fabric, a spunbond nonwoven fabric, a melt blown nonwoven fabric, a spunlace nonwoven fabric, and a needle punch nonwoven fabric may be mentioned. Moreover, the film etc. which enabled liquid permeation | transmission by the opening means can also be used. When using a nonwoven fabric as the sheet material, the fineness of the constituent fibers is preferably 1 to 20 dtex, particularly 1.5 to 4 dtex, from the viewpoints of securing the strength of the surface sheet and improving the touch.

The basis weight of the first layer 21 is preferably 10 to 45 g / m ² , particularly preferably 10 to 30 g / m ² . On the other hand, the basis weight of the second layer 22 is preferably 5 to 40 g / m ² , particularly preferably 10 to 30 g / m ² . In addition, it is preferable that the sum total of the basic weight of the 1st layer 21 and the 2nd layer 22 is 50 g / m < ² > or less.

  Moreover, as a constituent material of the elastic member constituting the concavo-convex sheet 20, various known elastic materials used for absorbent articles such as disposable diapers and sanitary napkins can be used without particular limitation. Examples thereof include synthetic rubbers such as styrene-butadiene, butadiene, isoprene and neoprene, natural rubber, EVA, stretchable polyolefin, polyurethane and the like. As a form, a thread-like or string-like (flat rubber etc.) or tape-like cross section having a rectangular, square, circular, or polygonal cross section, or a multifilament type thread-like one can be used.

  The concavo-convex sheet 20 can be manufactured by a gear stretching method in which a pair of gears having tooth grooves engaged with each other is used and the sheet is engaged with the gears. The shape of the gear may be a pair of gear rolls (wave rolls) in which the tooth gaps are engaged in a gear shape, or may be a flat plate shape. The concavo-convex sheet 20 can be manufactured, for example, according to the manufacturing method of the three-dimensional sheet described in Japanese Patent Application Laid-Open No. 2005-319370 related to the previous application of the present applicant.

  Hereinafter, the diaper 1 of 1st Embodiment is further demonstrated. As shown in FIGS. 1 and 2, the diaper 1 has a pair of three-dimensional bodies in which one side edge side is fixed on both sides in the longitudinal direction and the other side edge side can stand on the skin contact surface side of the surface sheet 2. The gathers 10 and 10 are provided. The three-dimensional gather 10 includes a belt-like sheet 11 and one or a plurality (two in the first embodiment) of three-dimensional gather forming elastic members 12 fixed to the belt-like sheet 11 in an expanded state. As shown in FIG. 2, the belt-like sheet 11 has one side edge in the width direction fixed on the skin contact surface of another member and the fixed edge 13 as a rising base end 13. The other side edge side opposite to the one side edge side is able to stand above the skin contact surface of the topsheet 2. The belt-like sheet 11 extends from the rising base end portion 13 outward in the width direction of the diaper 1, and is joined to the back sheet 3 at the extended portion. In addition, the belt-like sheet 11 is bonded on the top sheet 2 or the back sheet 3 also at the longitudinal front and rear end portions of the diaper 1.

  One or a plurality of (two in the first embodiment) leg elastic members 14 are arranged substantially linearly on both side portions along the longitudinal direction of the diaper 1. The leg elastic member 14 is sandwiched and fixed in an extended state between the belt-like sheet 11 and the back sheet 3 on the outer side in the width direction than the elastic member 12 for forming a three-dimensional gather. As a result, leg gathers are formed.

  In addition, a waist elastic member 15 is disposed at a longitudinal end portion of the diaper 1 in the back side portion A and its vicinity (waist portion) to form a waist gather. The waist elastic member 15 has a belt-like form, and is clamped and fixed between the top sheet 2 and the back sheet 3 over substantially the entire width along the width direction of the diaper 10. Further, a plurality of waistline gather forming elastic members 16 are disposed on both sides of the waistline portion of the back side portion A to form a pair of left and right waistline gathers. The elastic members 16 for forming the waistline gathers are arranged substantially linearly in the width direction, and are sandwiched and fixed between the top sheet 2 and the back sheet 3. As shown in FIG. 1, the waistline portion in the back side portion A has the diaper 1 in a state (expanded state) in which the elastic members of the respective portions are stretched and expanded in a flat shape, the back side portion A side on the upper side, When the side B side is considered as the lower side, the region is located below the waist and above the crotch C.

  Moreover, the diaper 1 of 1st Embodiment is an expansion | deployment type diaper, and a pair of fastening tape 17 is attached to the both-sides edge part in one edge part of a longitudinal direction. A landing tape 18 for fastening the fastening tape 17 is affixed to the outer surface (non-skin contact surface) of the abdominal side B.

  The material for forming each part of the diaper 1 will be described. As the back sheet 3 and the belt-like sheet 11 (three-dimensional gather forming sheet), various types conventionally used in the technical field can be used. Or non-moisture permeable resin film (perforated film); laminate of the resin film and nonwoven fabric; water-repellent nonwoven fabric (thermal bond nonwoven fabric, spunbond nonwoven fabric, spunbond-meltblown spunbond nonwoven fabric, spunbond-meltblown meltmelt blow) N-spunbond nonwoven fabric etc.) can be used. Further, as the various elastic members 12, 14, 15, and 16, the same elastic members that constitute the concavo-convex sheet 20 described above can be used.

  In addition, as the absorbent body 4, those used as absorbent bodies in the technical field can be used without particular limitation. For example, a fiber aggregate made of hydrophilic fibers such as wood pulp, What hold | maintained the particulate water-absorbing resin etc. can be used. These fiber assemblies may be covered with a liquid-permeable core wrap sheet such as paper or nonwoven fabric.

  The disposable diaper 1 of 1st Embodiment can be used similarly to this kind of expandable disposable diaper. According to the disposable diaper 1 of the first embodiment, the coolant 5 disposed between the top sheet 2 and the absorber 4 is dissolved by the body fluid such as excreted urine, and the body fluid is absorbed by the endothermic reaction at that time. Since the temperature is lowered, the transpiration of body fluid is effectively suppressed. As a result, an increase in humidity in the clothing due to the transpiration of body fluid such as urine is suppressed, and the occurrence of discomfort such as stuffiness and stickiness while wearing the diaper 1 is effectively prevented. Moreover, although the temperature fall of the bodily fluid by such a coolant 5 may give a cold and unpleasant feeling for a wearer, the diaper 1 of 1st Embodiment was mentioned above as the surface sheet 2 which covers the coolant 5. Since the bulky nonwoven fabric is provided, coldness (discomfort) caused by the coolant 5 can be prevented in advance, and the comfort is excellent.

  Next, other embodiment of the absorbent article of this invention is described with reference to drawings. About other embodiment of the absorptive article mentioned below, the part different from diaper 1 of a 1st embodiment mentioned above is mainly explained, the same numerals are given to the same component, and explanation is omitted. The description about the diaper 1 of 1st Embodiment is applied suitably to the component which is not demonstrated in particular.

  FIG. 4 is a cross-sectional view (corresponding to FIG. 2) in the width direction of a disposable diaper that is a second embodiment of the absorbent article of the present invention. In the diaper of the second embodiment, a liquid diffusable sheet 6 is disposed between the top sheet 2 and the coolant 5. The liquid diffusive sheet 6 is disposed so as to cover at least the coolant 5. With such a configuration, the temperature of the urine cooled by the coolant 5 becomes more difficult to be transmitted to the wearer's skin, and the comfort is further increased. The liquid diffusable sheet 6 in the second embodiment has the same shape and size as the absorbent body 4 in plan view, and covers not only the urination point and the vicinity thereof, but also the entire skin contact surface of the absorbent body 4. ing. The liquid diffusable sheet 6 and the surface sheet 2 may be bonded to each other at a predetermined portion by a bonding means such as an adhesive.

The liquid diffusive sheet 6 is preferably a sheet having excellent liquid diffusibility. For example, a spunlace nonwoven fabric, a spunbond nonwoven fabric, a spunbond-meltblown-spunbond (SMS) nonwoven fabric, or a fiber having a small fiber diameter (fineness of 3. An air-through nonwoven fabric made of a fiber having 0 dtex or less). Among these, an air-through nonwoven fabric made of fibers having a small fiber diameter is particularly preferable in terms of suppression of transpiration. The liquid diffusive sheet 6 has a basis weight of preferably 5 to 100 g / m ² , and more preferably 10 to 30 g / m ² from the viewpoint of ensuring the above-described effects.

  FIG. 5 is a cross-sectional view (corresponding to FIG. 2) in the width direction of a disposable diaper that is the third embodiment of the absorbent article of the present invention. In the diaper of the third embodiment, a liquid diffusible base sheet 7 is disposed between the top sheet 2 and the absorber 4, and the coolant 5 is supported in the base sheet 7. . As described above, by fixing the coolant in the base sheet, the coolant can be effectively prevented from moving or falling off, and the coolant is sprayed onto the absorber as in the first embodiment. Compared to the simple form, the feeling of firmness is reduced and the texture and wearing feeling are improved. The base sheet 7 in the third embodiment has the same shape and dimensions as the absorbent body 4 in plan view, and covers not only the urination point and the vicinity thereof, but also the entire skin contact surface of the absorbent body 4. Yes. The base sheet 7 and the top sheet 2 and the absorber 4 may be bonded to each other by a bonding means such as an adhesive at a predetermined portion.

As the base sheet 7, a sheet excellent in liquid diffusibility is preferable. For example, a spunlace nonwoven fabric, a spunbond nonwoven fabric, an SMS nonwoven fabric, or an air-through nonwoven fabric composed of fibers having a small fiber diameter (fibers having a fineness of 3.0 dtex or less) Is mentioned. Among these, a spunlace nonwoven fabric is particularly preferable in terms of fixing the coolant. Moreover, from the viewpoint of ensuring that the above-described effects are reliably exhibited, the basis weight of the sheet 7 in the state in which the coolant 5 is supported in the base sheet 7 is preferably 5 to 100 g / m ² , and Preferably it is 10-30 g / m < ² >. Moreover, the basic weight of the coolant 5 in the base material sheet 7 is preferably 5 to 100 g / m ² , more preferably 10 to 30 g / m ² .

  The state in which the coolant 5 is supported in the base material sheet 7 means that the coolant 5 enters the space formed by the constituent fibers of the base material sheet 7, and stress is applied to the base material sheet 7 from the outside. Even if added, it means a state where the coolant 5 is not easily moved or dropped. From the standpoint of making the carrying state of the coolant 5 stronger, a fusion fiber (binder fiber), a hot melt pressure-sensitive adhesive, a synthetic binder is provided between the coolant 5 and the constituent fibers of the base sheet 7. It may be bound by a binder such as.

  The state in which the coolant 5 is carried in the base material sheet 7 is produced, for example, by manufacturing a base material sheet that does not contain a coolant and immersing the base material sheet in a liquid containing a separately prepared coolant. It is obtained by the method to do.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said embodiment. For example, in the first and second embodiments [the coolant is disposed between the top sheet and the absorbent body (the state in which the coolant is not supported in the base sheet)], the coolant and the absorption A liquid-permeable bulky sheet (not shown) may be disposed between the body and the body. With such a configuration, the vapor released from the absorber is more effectively suppressed.

As the bulky sheet, for example, an air-through nonwoven fabric can be used. The shape and dimensions of the bulky sheet in plan view can be the same as those of the absorber 4. The bulky sheet has a thickness under a load of 3.5 kPa, preferably 0.3 to 10 mm, more preferably 0.5 to 3 mm, and a basis weight of preferably 5 to 100 g / m ² , more preferably 10 to 30 g. / M ² .

  Moreover, in the said embodiment, although the coolant was distribute | arranged between the surface sheet 2 and the absorber 4, you may distribute | arrange between the absorber 4 and the back surface sheet 3. FIG. In that case, the arrangement form of the coolant 5 in the first embodiment can be used as appropriate, or, as in the third embodiment, the coolant is supported in the base sheet and the base sheet is made of the absorber 4. And the back sheet 3 may be disposed.

  Moreover, in the said embodiment, although what was called a deployment type disposable diaper was mentioned as one of the application examples of the absorbent article of this invention, the underpants type disposable diaper shape | molded in the underpants type, a urine pad, and sanitary use It can also be applied to napkins and the like. When the present invention is applied to a urine collection pad, the back sheet of the urine collection pad may be liquid permeable or liquid impermeable.

  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]
A disposable diaper having a configuration as shown in FIGS. 1 and 2 was produced and used as a sample of Example 1. As shown in FIG. 3, an air-through nonwoven fabric (concave / convex sheet) having a three-dimensional shape as shown in FIG. 3 is used as a surface sheet (bulky nonwoven fabric), and pulp fibers (basis weight 130 g / m ² ) and particulate water-absorbing resin (tsubo) 104 g / m ² ) and coated with tissue paper, urea (4 g) as a coolant, between the top sheet and the absorber in the 50 mm square area located near the urination point In a uniformly dispersed state. It was 96% when the space occupation rate of the surface sheet (uneven | corrugated sheet | seat) in Example 1 was measured by the said measuring method.

The surface sheet (uneven sheet) in Example 1 is a sheet having a two-layer structure including a first layer and a second layer, and as a sheet material of the first layer (a layer directed to the skin side of the wearer) Using an air-through nonwoven fabric A having a hydrophilicity of 18 g / m ² and a sheet material for the second layer (layer disposed on the outer side), the air-through nonwoven fabric having a basis weight of 18 g / m ² and having been hydrophilicized B was used. The constituent fibers of the air-through nonwoven fabric A are two types of core-sheath type composite fibers having different finenesses (the core part is polypropylene (PP) and the sheath part is polyethylene (PE)). The composite fiber having a fineness of 4.4 dtex and 67% by weight of the total constituent fiber of the nonwoven fabric A was contained. The constituent fiber of the air-through nonwoven fabric B was a core-sheath type composite fiber having a core part of polyethylene terephthalate (PET) and a sheath part of PE, and the fineness of the composite fiber was 2.2 dtex.

  The top sheet (uneven sheet) in Example 1 was produced as follows. First, the first layer sheet material (air-through non-woven fabric A) is bitten between a pair of gear rolls having gear teeth that mesh with each other, and then the three-dimensional shaping is performed, and then the first layer of the three-dimensional shaping is made. The sheet material and the second-layer sheet material (air-through nonwoven fabric B) are overlapped and sandwiched between a roll having a tooth groove on the peripheral surface and a roll having a smooth peripheral surface (anvil roll), and both are heat-sealed. And integrated to obtain an uneven sheet.

[Comparative Example 1]
Disposable in the same manner as in Example 1 except that air-through nonwoven fabric C (thickness 0.1 mm when loaded with 3.5 kPa, basis weight 25 g / m ² , space occupancy 73%) is used as the topsheet. A diaper was prepared and used as a sample of Comparative Example 1. The constituent fibers of the air-through nonwoven fabric C are two types of core-sheath type composite fibers (core portion is PP and sheath portion is PE) having different finenesses. The composite fibers having a fineness of 3.3 dtex are 58% of the total constituent fibers of the nonwoven fabric C. The composite fiber having a weight% and a fineness of 2.2 dtex was contained in 42% by weight of all the constituent fibers of the nonwoven fabric C.

[Comparative Example 2]
A disposable diaper was produced in the same manner as in Comparative Example 1 except that no coolant was used, and this was used as a sample of Comparative Example 2.

[Evaluation]
About the sample (disposable diaper) of an Example and a comparative example, maximum humidity, a feeling of contact cold / warmness (Q-max), and comfort were evaluated. These results are shown in Table 1 below.

[Maximum humidity evaluation method]
In a room maintained at a room temperature of 32 ° C. and a humidity of 52% RH, the sample is expanded in a flat shape by stretching the elastic members of each part with the skin contact surface side (surface sheet side) facing upward as shown in FIG. 40 g of artificial urine warmed to 40 ° C. was injected at a time into the urination point of the sample, and the humidity (%) at the urination point from immediately after injection until 5 minutes later was measured with a thermometer. The maximum value of humidity for 5 minutes was defined as the maximum humidity (%). The smaller the maximum humidity value, the lower the urinary transpiration and the higher the rating.

[Evaluation method for feeling of cold contact (Q-max)]
In a room maintained at a room temperature of 23 ° C. and a humidity of 50% RH, the sample is expanded in a flat shape by stretching the elastic member of each part with the skin contact surface side (surface sheet side) up as shown in FIG. 40 g of artificial urine warmed to 40 ° C. was injected into the urination point of the sample at a time, and after 2 minutes, the contact cold / warm feeling (Q-max) at the time of 3.5 kPa load was measured with KES-7 Thermolab II. Measured with a mold (manufactured by Kato Tech Co., Ltd.) Specifically, a pure copper plate (heat capacity 0.41855 J / ° C.) with an area of 9 cm ² and a total weight of 31.5 g placed on the weight was heated to 33 ° C., and the pure copper plate was placed on the top sheet of the sample. In the state, artificial urine was injected into the urination point, and Q-max (kw / m ² ) after 2 minutes was measured. Q-max is the amount of heat that flows when a hot plate with a certain finite amount of heat is brought into contact with the sample, and correlates with the feeling of coldness in the contact. The smaller the Q-max value, the cooler the diaper wearer feels. There is little (discomfort) and it is highly evaluated.

[Method of evaluating comfort]
In a room maintained at a room temperature of 23 ° C. and a humidity of 50% RH, the sample is expanded in a flat shape by stretching the elastic member of each part with the skin contact surface side (surface sheet side) up as shown in FIG. When 40 g of artificial urine warmed to 40 ° C. is injected into the urination point of the sample at a time, and after 2 minutes, the surface of each sample is touched by hand, and no coldness or stuffiness is felt. The case where coldness was felt was x1, and the case where sultry was felt was x2.

  As is apparent from the results in Table 1, the cold feeling when Example 1 is touched compared to Comparative Examples 1 and 2 when the maximum humidity is small and transpiration of urine is suppressed and the value of Q-max is small. Because it is small, it is excellent in comfort. In contrast, although Comparative Example 1 uses a coolant, the surface sheet is not mainly a bulky non-woven fabric (thickness at a load of 3.5 kPa is less than 0.3 mm). ), The result was inferior to Example 1. In Comparative Example 2, the top sheet was not a bulky nonwoven fabric, and since no coolant was used, the maximum humidity was particularly large and the urine transpiration suppression effect was poor.

FIG. 1 is a skin contact surface side (surface sheet side) schematically showing a state in which the disposable diaper which is the first embodiment of the absorbent article of the present invention is expanded in a flat shape by extending the elastic members of each part. It is a top view. 2 is a cross-sectional view schematically showing a cross section taken along line XX of FIG. FIG. 3 is an enlarged perspective view of a main part of the top sheet in the diaper shown in FIG. FIG. 4 is a view corresponding to FIG. 2 of the second embodiment of the absorbent article of the present invention. FIG. 5 is a view corresponding to FIG. 2 of a third embodiment of the absorbent article of the present invention.

Explanation of symbols

1 disposable diaper (absorbent article)
2 Top sheet (bulky nonwoven fabric)
3 Back sheet 4 Absorber 5 Coolant 6 Liquid diffusive sheet 7 Base sheet 10 Three-dimensional gather 20 Uneven sheet (bulky nonwoven fabric)
A dorsal side B ventral side C inseam

Claims (4)

An absorbent article comprising a top sheet that forms a skin contact surface, a back sheet that forms a non-skin contact surface, and an absorbent body interposed between both sheets,
Between the top sheet and the back sheet, a coolant that dissolves and absorbs heat in urine excreted by the wearer is disposed, and the top sheet has a thickness of 0.3 mm or more at a load of 3.5 kPa. Formed from a bulky nonwoven fabric having an amount of 50 g / m ² or less ,
An absorbent article in which a liquid-diffusible base sheet is disposed between the top sheet and the absorber, and the coolant is supported in the base sheet .   The absorbent article according to claim 1, wherein the coolant is disposed between the top sheet and the absorber. An absorbent article comprising a top sheet that forms a skin contact surface, a back sheet that forms a non-skin contact surface, and an absorbent body interposed between both sheets,
Between the top sheet and the back sheet, a coolant that dissolves and absorbs heat in urine excreted by the wearer is disposed, and the top sheet has a thickness of 0.3 mm or more at a load of 3.5 kPa. Formed from a bulky nonwoven fabric having an amount of 50 g / m ² or less,
The coolant is disposed between the topsheet and the absorber;
Between the coolant and the surface sheet, absorption Osamusei article that have been arranged for the liquid-diffusing sheet. The absorbent article according to any one of claims 1 to 3 , wherein the bulky nonwoven fabric is an uneven sheet having an uneven shape on a surface.

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