JP2016005545A - Disposable diaper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disposable diaper that improves quality of a product by making it agreeable to the touch and that suppresses an increase in cost.SOLUTION: In a disposable diaper 1 of the present invention, an outer layer sheet 51 of an exterior body 5 forming an outer surface of the disposable diaper 1 is made of a spunbonded nonwoven fabric. In the spunbonded nonwoven fabric of the outer layer sheet, its basis weight is 19 g/mor less; an average deviation SMD of its surface roughness is 3.20 μm or less: an average deviation MMD of its coefficient of friction is 0.0085 or less; and its MD bulk softness is 5.0 cN or less.

Description

  The present invention relates to a disposable diaper.

  In absorbent articles such as disposable diapers, a spunbonded nonwoven fabric is used as a part of the constituent members. In general, spunbonded nonwoven fabrics are characterized by low cost, low rigidity, and no distortion, but many are inferior in smoothness and softness. For example, Patent Document 1 describes a spunbonded nonwoven fabric that can be suitably used as a surface material for disposable diapers. Patent Document 2 describes a disposable diaper using a spunbonded nonwoven fabric as an exterior body of a pants-type disposable diaper.

  If the disposable diaper is comprised using the spun bond nonwoven fabric of patent document 1 for a surface material, cost can be held down. Moreover, according to the underpants-type disposable diaper described in Patent Document 2, since the exterior body is composed of a spunbond nonwoven fabric, the cost can be suppressed, and the spunbond nonwoven fabric described in Patent Document 2 is surface active. Since it is formed including an agent, smoothness is improved.

  Separately from this, the present applicant has previously disclosed an air-through nonwoven fabric that defines an average deviation of surface roughness and an average deviation of friction coefficient as a nonwoven fabric used as a constituent material of the outermost surface of a disposable diaper (patent) Reference 3).

Japanese Patent Laid-Open No. 2001-146684 JP 2010-273960 A JP 2006-233364 A

  However, Patent Document 1 does not describe anything about a smooth, draped, and soft fabric-like viewpoint as a characteristic required for a spunbonded nonwoven fabric. Therefore, when the spunbonded nonwoven fabric described in Patent Document 1 is used as a constituent material of the outermost surface of the disposable diaper, the touch is poor and the quality of the product is deteriorated.

  In addition, since the spunbond nonwoven fabric described in Patent Document 2 is formed to include a surfactant, the smoothness that is one factor of cloth-like is improved. Nothing is stated about the requirements for cloth-like. For this reason, when the spunbonded nonwoven fabric described in Patent Document 1 is used as a constituent material of the outermost surface of the disposable diaper, the touch is uncomfortable and the quality of the product is deteriorated.

  Moreover, the nonwoven fabric used as a constituent material of the outermost surface of the disposable diaper described in Patent Document 3 is an air-through nonwoven fabric, and it is difficult to keep costs low. Patent Document 3 does not describe any spunbonded nonwoven fabric that satisfies the cloth-like viewpoint.

  Therefore, this invention is providing the disposable diaper which can eliminate the fault which the prior art mentioned above has.

The present invention includes a top sheet, a back sheet, a vertically long absorbent main body provided with an absorbent body disposed between both sheets, and an exterior body disposed on the non-skin facing surface side of the absorbent main body. In the disposable diaper, the outer package has an outer layer sheet forming an outer surface of the disposable diaper, and the outer layer sheet is made of a spunbond nonwoven fabric, and the spunbond nonwoven fabric has a basis weight of 19 g / m. ^A disposable diaper having a surface roughness average deviation SMD of 3.20 μm or less, a friction coefficient average deviation MMD of 0.0085 or less, and an MD bulk softness of 5.0 cN or less. It is.

  According to the present invention, since the spunbonded nonwoven fabric having low rigidity and improved cloth-like property is used for the outer layer sheet forming the outer surface, the touch is good and the cost can be reduced.

FIG. 1 is a perspective view showing a usage state (wearing state) of a pants-type disposable diaper according to an embodiment of the present invention. FIG. 2 is a developed plan view of the diaper shown in FIG. 1 expanded and stretched from the skin contact surface side. FIG. 3 is a schematic view showing a suitable processing device used when raising a spunbonded nonwoven fabric. FIG. 4 is a schematic view of a partially stretched portion of the processing apparatus shown in FIG. FIG. 5 is a schematic view of the raised portion of the processing apparatus shown in FIG. 3 as viewed obliquely. FIG. 6 is an enlarged plan view showing, in an enlarged manner, a fusion part row of the diaper shown in FIG. 1 and an outer package fusion part constituting the fusion part row. FIG. 7 is an enlarged cross-sectional view showing a cross section along the horizontal direction of the waist stretchable part in the diaper shown in FIG. 1. FIG. 8 is an enlarged cross-sectional view showing a cross section along the lateral direction of the waistline stretchable part in the diaper shown in FIG. 1.

  Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings. A disposable diaper 1 according to an embodiment of the present invention is disposed between a liquid-permeable top sheet 2, a liquid-impermeable back sheet 3, and both the sheets 2 and 3, as shown in FIGS. It is a diaper comprising a vertically long absorbent main body 10 provided with the absorbent body 4 and an exterior body 5 disposed on the non-skin facing surface side of the absorbent main body 10. In the present embodiment, the diaper 1 is divided into an abdominal side portion that is disposed on the abdomen side of the wearer, a back side portion that is disposed on the back side, and a crotch portion that is located between them. A pair of side seal portions S, S are formed by joining both side edges of the abdominal side and both side edges of the back side. Specifically, in the diaper 1, the exterior body 5 is positioned between the abdominal exterior body 5A disposed on the wearer's stomach side, the back exterior body 5B disposed on the back side, and between these 5A and 5B. The crotch outer body 5C disposed in the crotch region is divided as a separate member, and both side edges 5a1, 5a1 of the abdominal side body 5A and both side edges 5b1, 5b1 of the back side body 5B are joined. A so-called pants-type disposable diaper in which a pair of side seal portions S, S, a waist opening WO, and a pair of leg openings LO, LO are formed.

The diaper 1 has a longitudinal direction (X direction) corresponding to the wearer's front-rear direction and a lateral direction (Y direction) orthogonal to the wearer's front-rear direction as shown in FIG. Have. Moreover, the diaper 1 is the abdominal area A distribute | arranged to the wearer's ventral side at the time of wear in the vertical direction (X direction), the dorsal area | region B distribute | arranged to the wearer's back side at the time of wear It is divided into a crotch region C located between A and the back region B. Moreover, in this specification, a skin opposing surface is a surface which faces a wearer's skin side at the time of wear in the diaper 1 or its structural member (for example, absorbent main body 10), and a non-skin opposing surface is a pants-type disposable. It is a surface in the diaper 1 or its constituent member that is directed to the side opposite to the wearer's skin side (clothing side) when worn. In the diaper 1, the vertical direction (X direction) coincides with the direction along the long side of the absorbent main body 10 that is the diaper 1 or a constituent member thereof, and the lateral direction (Y direction) is a disposable diaper or a constituent member thereof. It corresponds to the width direction of the absorbent main body 10.
Moreover, the diaper 1 is symmetrical with respect to the longitudinal center line CL extending in the longitudinal direction (X direction). Accordingly, in the following description, only one of the symmetrical parts will be mainly described.

  In addition, as shown in FIG. 2, the state which expanded and extended the diaper 1 mentioned above peels off the side seal | sticker part S, makes the diaper 1 an expansion | deployment state, and sets the diaper 1 of the expansion | deployment state to each part. It means a state in which the elastic member is extended and expanded to the design dimension (same as the dimension when the elastic member is expanded in a flat state with no influence of the elastic member).

  As shown in FIG. 2, the absorbent main body 10 has a vertically long shape in which one direction (longitudinal direction (X direction)) is relatively long. The absorbent main body 10 includes a liquid-permeable surface sheet 2 that forms a skin-facing surface, a liquid-impermeable back surface sheet (including water repellency) that forms a non-skin-facing surface, and both the sheets 2 and 3. And a liquid-retaining absorbent 4 interposed therebetween. Moreover, as shown in FIG. 2, the side cuffs 6 and 6 which have the elastic member distribute | arranged by extending in the vertical direction (X direction) in the both sides along the vertical direction (X direction) of the absorptive main body 10 are shown. Is provided. Specifically, the side cuff 6 is made of a liquid-impermeable or water-repellent and breathable material, and a three-dimensional gather forming elastic member 61 is provided in the vicinity of the free end of each side cuff 6. Are extended in the vertical direction (X direction). When the diaper is worn, the free end portion of the side cuff 6 rises due to the contraction of the elastic member 61 for forming the three-dimensional gather, so that a so-called three-dimensional gather is formed, and the outflow of body fluid in the lateral direction (Y direction) is prevented.

  The absorbent main body 10 configured as described above is bonded to the central portion of the outer package 5 with its longitudinal direction (X direction) aligned with the longitudinal direction (X direction) of the diaper 1 in the unfolded and expanded state. It is joined by the agent. As described above, the exterior body 5 is disposed and fixedly bonded to the non-skin facing surface side of the back sheet 3 constituting the absorbent main body 10 in the thickness direction (Z direction) of the disposable diaper 1. Specifically, as described above, the exterior body 5 of the diaper 1 includes the abdominal exterior body 5A located in the abdominal area A, the back exterior body 5B located in the back area B, and these (ventral side exteriors). The crotch exterior body 5C located in the crotch region C located between the body 5A and the back exterior body 5B) is configured as a separate member, and the abdominal exterior body 5A, the back exterior body 5B, and the crotch exterior body 5C. It is classified as. The exterior body 5 is integrally formed by joining the abdominal exterior body 5A and the back exterior body 5B to both ends in the longitudinal direction (X direction) of the crotch exterior body 5C. The absorbent main body 10 is joined to the central portion in the lateral direction (Y direction) of the exterior body 5 formed in this way, and the absorbent main body 10 is arranged from the ventral exterior body 5A to the back exterior body 5B. Has been.

  The exterior body 5 has an outer layer sheet 51 that forms the outer surface of the disposable diaper 1, and the outer layer sheet 51 is formed of a spunbonded nonwoven fabric. Specifically, as shown in FIG. 2, the ventral exterior body 5A and the back exterior body 5B in the diaper 1 are both rectangles that are long in the lateral direction (Y direction) in the unfolded and extended state (see FIG. 2). It has a shape. The ventral exterior body 5 </ b> A and the back exterior body 5 </ b> B in the diaper 1 are both an outer layer sheet 51 that forms the outer surface of the diaper 1, and an inner layer sheet 52 that is disposed on the inner surface side of the outer layer sheet 51 and forms the inner surface of the diaper 1. The diaper 1 further includes a plurality of thread-like elastic members 53 arranged in an extended state in the lateral direction (Y direction) between the outer layer sheet 51 and the inner layer sheet 52. It is configured. The abdominal exterior body 5A and the back exterior body 5B have a known bonding method such as fusion between the outer layer sheet 51 and the inner layer sheet 52 such as heat sealing, high frequency sealing, or ultrasonic sealing, or an adhesive. Preferably, the diaper 1 is partially joined at an outer package fusion part 54 by fusion, which will be described later. In the diaper 1, the outer layer sheets 51 of the stomach side exterior body 5A and the back side exterior body 5B are formed of spunbonded nonwoven fabric.

  The crotch outer body 5C in the diaper 1 is formed of a single sheet (outer layer sheet 51) that forms the outer surface of the diaper 1. The crotch outer body 5 </ b> C covers a crotch region C portion in the back sheet 3 that constitutes the absorbent main body 10. Both side edges along the diaper longitudinal direction (X direction) of the crotch outer body 5C substantially coincide with both side edges along the longitudinal direction (X direction) of the back sheet 3 constituting the absorbent main body 10, and the crotch outer body 5C Is formed in a rectangular shape. In the diaper 1, the outer layer sheet 51 of the crotch outer body 5C is formed from a spunbonded nonwoven fabric.

The spunbonded nonwoven fabric of the outer layer sheet 51 is a nonwoven fabric that satisfies all of the following requirements (1) to (4), and is preferably a nonwoven fabric that satisfies all of the following requirements (1) to (5). This will be specifically described below.
The spunbonded nonwoven fabric of the outer layer sheet 51 has a basis weight (requirement (1)) of 19 g / m ² or less and preferably 18 g / m ² or less from the viewpoint of reducing rigidity. In addition, as a lower limit of the basic weight of a spun bond nonwoven fabric, it is preferable that it is 10 g / m < ² > or more.

  The spunbonded nonwoven fabric of the outer layer sheet 51 has an average deviation SMD (requirement (2)) of the surface roughness of 3.20 μm or less, preferably 3.1 μm or less, and preferably 3.0 μm or less. Further preferred. The lower limit of the average deviation SMD of the surface roughness of the spunbonded nonwoven fabric is preferably as close as possible to 0, but if it is 0.5 μm or more, sufficient smoothness is imparted to the nonwoven fabric.

  The spunbonded nonwoven fabric of the outer layer sheet 51 has an average deviation MMD (requirement (3)) of the friction coefficient of 0.0085 or less, and preferably 0.0075 or less. The lower limit value of the average deviation MMD of the friction coefficient of the spunbonded nonwoven fabric is preferably as close as possible to 0, but if it is 0.003 or more, sufficient smoothness is imparted to the nonwoven fabric.

The average deviation SMD of the surface roughness and the average deviation MMD of the friction coefficient are measured using KESFB4-AUTO-A (trade name) manufactured by Kato Tech Co., Ltd. according to the method described in the following books. Specifically, it is measured by the following method.
Kakio Kawabata, “Standardization and analysis of texture evaluation”, 2nd edition, Japan Textile Opportunity Society, Texture Measurement and Standardization Research Committee, published on July 10, 1980

[Measurement method of average deviation SMD of surface roughness]
A test piece (outer layer sheet 51) of 20 cm × 20 cm is prepared and attached to a smooth metal flat test table. The contact is pressed against the test piece with 9.8 cN (within ± 0.49 cN error). The specimen is moved 2 cm horizontally at a constant speed of 0.1 cm / sec. The specimen is given a uniaxial tension of 19.6 cN / cm. The contact consists of a 0.5 mm diameter piano wire bent in a U shape with a width of 5 mm, and a test piece is crimped at 9.8 cN. The contact is crimped with a spring. The spring constant is 24.5 cN / mm (within an error of ± 0.98 cN / mm), and the resonance frequency is 30 Hz or more in a state away from the surface contact. The measured value of the average deviation of the surface roughness is represented by the SMD value. This measurement is performed for both MD and CD, and an average value is obtained from the following formula (1), which is defined as an average deviation SMD of the surface roughness.
Average deviation of surface roughness SMD = {(SMD _MD ² + SMD _CD ² ) / 2} ^1/2 (1)

[Measuring method of mean deviation MMD of friction coefficient]
A test piece (outer layer sheet 51) of 20 cm × 20 cm is prepared and attached to a smooth metal flat test table. The contact surface is pressure-bonded to the test piece with a force of 49 cN, and the test piece is moved horizontally by 2 cm at a constant speed of 0.1 cm / sec. The specimen is given a uniaxial tension of 19.6 cN / cm. The contact was made by arranging 20 piano wires with the same diameter of 0.5 mm as the contact used for measuring the surface roughness and bending it into a U shape with a width of 10 mm. The contact surface was tested with a force of 49 cN using a weight. Crimped to a piece. The measured value of the average deviation of the friction coefficient is expressed as an MMD value. This measurement is performed for both MD and CD, and an average value is obtained from the following formula (2), which is defined as an average deviation MMD of the friction coefficient.
Mean deviation of friction coefficient MMD = {(MMD _MD ² + MMD _CD ² ) / 2} ^1/2 (2)

  The spunbonded nonwoven fabric of the outer layer sheet 51 has an MD bulk softness (requirement (4)) of 5.0 cN or less, preferably 4.0 cN or less, and more preferably 3.5 cN or less. In addition, as a lower limit of MD bulk softness of a spunbond nonwoven fabric, it is so preferable that it is near 0, but if it is 0.5 cN or more, sufficient drape property will be provided to a nonwoven fabric. MD bulk softness is measured by the following measurement method.

[Measurement method of MD bulk softness]
The MD bulk softness is 22 mm in a 65% RH environment, and the outer layer sheet 51 is cut in the CD direction along the orientation direction of the constituent fibers by 150 mm, in the MD direction perpendicular to the CD direction by 30 mm, and in a ring shape with a diameter of 45 mm. Use staples to stop the edges at the top and bottom. At this time, the stapler core is elongated in the CD direction. Using a tensile tester (for example, Tensilon tensile tester “RTA-100” manufactured by Orientec Co., Ltd.), the ring is placed in a cylindrical shape on the sample stage, and the compression speed is 10 mm on a flat plate substantially parallel to the stage from above. The maximum load when compressed at a speed of / min is measured, and the measured value in the MD direction is defined as MD bulk softness.

The spunbonded nonwoven fabric of the outer layer sheet 51 preferably has a compression characteristic value (requirement (5)) of 15.0 (gf / cm ² ) / mm or less at the time of a minute load, and 14.0 (gf / cm ² ) / mm or less is more preferable, and 13.0 (gf / cm ² ) / mm or less is particularly preferable. The lower limit of the compression characteristic value of the spunbonded nonwoven fabric at a minute load is preferably closer to 0, but if it is 1.0 (gf / cm ² ) / mm or more, the nonwoven fabric has a sufficiently soft feeling. Is granted. The compression characteristic value at a minute load is measured by the following measuring method.

[Measurement method of compression characteristic value at minute load]
The measurement of the data that is the basis for calculating the compression characteristic value at the time of a minute load is performed using KES FB3-AUTO-A (trade name) manufactured by Kato Tech Co., Ltd. in an environment of 22 ° C. and 65% RH. Specifically, three outer sheets 51 are cut into 20 cm × 20 cm to prepare measurement samples. Next, one of the measurement samples is placed on the test bench. Next, it compresses between the steel plates of a circular plane with an area of 2 cm < ² >. The compression speed is 20 μm / sec, the maximum compression load is 10 gf / cm ² , and the recovery process is also measured at the same speed. At this time, the displacement amount between the steel plates is set to x (mm), the load is set to y (gf / cm ² ), and the position of the point where the load is detected is set to x = 0 and measured in the compression direction. The value of x increases as it is compressed.

The compression characteristic value at the minute load is calculated by extracting the deformation amount of the thickness at the minute load from the measured data (x, y). Specifically, the first load that is not a recovery process, a load between 0.30 gf / cm ² and 1.00 gf / cm ² and the deformation data at that time are extracted, and the relationship between x and y is approximated A straight line is obtained by the method of least squares, and the slope at that time is taken as the above characteristic value (unit (gf / cm ² ) / mm). Three points are measured with one measurement sample. A total of 9 points of 3 samples are measured. The characteristic values at each of the nine locations are calculated, and the average value is set as the compression characteristic value when the nonwoven fabric is subjected to a minute load.

  The spunbond nonwoven fabric of the outer layer sheet 51 is preferably formed from a propylene-based polymer that is a polyolefin-based polymer from the viewpoint of becoming a flexible nonwoven fabric. The propylene polymer is preferably a propylene polymer having a molecular weight distribution (Mn / Mn) of 1.5 or more and 3.5 or less. Moreover, as a propylene-type polymer, from a viewpoint used as a smooth and flexible nonwoven fabric, 5 to 100 weight%, more preferably 25 to 80 weight% of any one or more of a random copolymer, a homopolymer, and a block copolymer is used. It is preferable that it consists of resin which contained. These copolymers and homopolymers may be mixed, other resins may be mixed, and a mixture of polypropylene homopolymer and random copolymer may be used. Furthermore, as a random copolymer based on a propylene component, a copolymer copolymerized with ethylene or an α-olefin is preferable, and an ethylene-propylene random copolymer is particularly preferable. From the same viewpoint, the propylene-based polymer is preferably a polymer containing 5 to 100% by weight of an ethylene-propylene random copolymer as a main component, and more preferably 25% by weight or more. preferable. In the ethylene-propylene random copolymer, the ethylene content is preferably 2.0 mol% or more and 10.0 mol% or less, and the ethylene content is more preferably 3.0 mol% or more and 8.0 mol% or less. Further, the propylene polymer is preferably a polymer containing 25% by weight or more of recycled polypropylene resin, and more preferably a polymer containing 50% by weight or more from the viewpoint of the environment.

  From the viewpoint of flexibility, the spunbonded nonwoven fabric of the outer layer sheet 51 preferably has a crimped long fiber content of 30% by mass or more, more preferably 40% by mass or more, and a morphological stability viewpoint. Therefore, it is preferably 100% by mass or less, more preferably 90% by mass or less, and specifically, from 30% by mass to 100% by mass from the viewpoint of compatibility between flexibility and form stability. It is preferable that it is 40 mass% or more and 90 mass% or less.

  Here, the crimped continuous fiber is, for example, melt-spun thermoplastic resin and then cooling the melt-spun filament by applying cooling air at different temperatures from the left and right or front and rear, or cooling air from one side.捲 which is formed by cooling with contact or cooling or cooling a filament that has been melt-spun as a modified cross-section fiber or an eccentric hollow fiber, or a complex melt-spun filament using a polymer having a different melting point The fiber which shrinks is shown. The crimped long fiber is usually an actual crimped long fiber having a number of crimps of preferably 10 pieces / 25 mm or more, more preferably 15 pieces / 25 mm or more, and particularly preferably 20 pieces / 25 mm or more. In general, the actual crimped filaments preferably have a fiber diameter in the range of 0.5d to 5.0d, and more preferably in the range of 0.5d to 3.0d. In addition, the number of crimps of the crimped long fiber is measured by the following measuring method.

[Measurement method of crimped number of crimped long fibers (pieces / 25 mm)]
A dividing line with a spatial distance of 25 mm is drawn on a piece of paper having a smooth surface and gloss. Next, each of the crimped long fibers carefully collected from the long fiber web before being heated and pressurized by the embossing roll so as not to impair the crimpability is 25 ± 5% of the spatial distance. Applying looseness, both ends are pasted and fixed to the piece of paper with an adhesive. One sample at a time, attached to the grip of the crimping tester, cut the piece of paper, and then the distance between the grips when the initial load (0.18 mN x number of tex) is applied to the sample (spatial distance) ( mm). Then, the number of crimps at that time is counted, and the number of crimps per 25 mm is obtained. The number of crimps counts all the peaks and valleys, and the half of the number is the crimp number. As for the number of crimps, only the crimped long fibers are taken out of the nonwoven fabric, 20 are measured, and the average value obtained up to one decimal point is defined as the number of crimps. Note that the number of crimps is measured in a temperature-controlled room at a temperature of 20 ± 2 ° C. and a humidity of 65 ± 2% as defined in JIS Z8703 (standard state of the test site).

  The spunbonded nonwoven fabric of the outer layer sheet 51 preferably has a breaking strength in the direction perpendicular to the orientation direction of the constituent fibers of 7.0 N / 50 mm or more from the viewpoint of prevention of breakage during use and processability. 7.0 N / 50 mm or more, preferably 30.0 N / 50 mm or less, specifically 7.0 N / 50 mm or more and 30.0 N / 50 mm or less, and 8. More preferably, it is 0 N / 50 mm or more and 30.0 N / 50 mm or less. The breaking strength is measured by the following measurement method.

[Measurement method of breaking strength]
Under an environment of 22 ° C. and 65% RH, the outer layer sheet 51 is cut into a rectangular shape of 50 mm in the CD direction along the orientation direction of the constituent fibers and 200 mm in the MD direction perpendicular to the CD direction. The cut measurement piece is used as a measurement sample. This measurement sample is attached to a chuck of a tensile tester (for example, Tensilon tensile tester “RTA-100” manufactured by Orientec Co., Ltd.) so that the MD direction becomes the tensile direction. The gap between chucks is 150 mm. Then, the measurement sample is pulled at a speed of 300 mm / min, and the maximum load point until the measurement sample is broken is defined as the breaking strength in the direction (MD direction) orthogonal to the orientation direction of the constituent fibers.

The spunbonded non-woven fabric of the outer layer sheet 51 has a plurality of heat-sealing portions that fix the constituent fibers and constitute the spunbonded non-woven fabric. From the viewpoint of forming a soft and soft non-woven fabric, each of the plurality of heat-sealing parts preferably has an area of 0.3 mm ² or less, and more preferably 0.1 mm ² or more and 0.25 mm ² or less. It is particularly preferably 0.1 mm ² or more and 0.2 mm ² or less. The number of heat-sealing parts is preferably 10 pieces / cm ² or more and 250 pieces / cm ² or less, and more preferably 35 pieces / cm ² or more and 65 pieces / cm ² or less.

  Further, the spunbonded nonwoven fabric of the outer layer sheet 51 has a total area ratio (embossing rate) of the plurality of heat-sealing portions in the surface area of one surface thereof, which is 15% or less from the viewpoint of becoming a soft and comfortable nonwoven fabric. It is preferably 5% or more and 13% or less, and particularly preferably 6% or more and 11% or less.

  The heat-sealed part constituting the spunbonded nonwoven fabric of the outer layer sheet 51 is formed intermittently by thermocompression bonding by embossing (by an embossed convex roll and flat roll), by ultrasonic welding, intermittently And the like which are partially fused by adding hot air to the above. Of these, thermocompression bonding is preferred in that the fiber can be easily broken. The shape of the heat fusion part is not particularly limited, and may be any shape such as a circle, a rhombus, and a triangle.

  The spunbonded nonwoven fabric of the outer layer sheet 51 is preferably subjected to raising treatment from the viewpoint of improving the touch. When raising a spunbonded nonwoven fabric, for example, a processing apparatus including a partially stretched portion 200 and a raised portion 300 disposed downstream of the partially stretched portion 200 as shown in FIG. 100.

  The partial stretch processing part 200 is a part that performs partial stretch processing on each of a plurality of portions of the raw material nonwoven fabric 51M of the spunbond nonwoven fabric of the outer layer sheet 51. In the processing apparatus 100, as shown in FIGS. A steel matching embossing roller 23 composed of uneven rolls 21 and 22 is provided. A pair of uneven | corrugated rolls 21 and 22 is a thing of metallic cylindrical shapes, such as an aluminum alloy or steel. The steel matching embossing roller 23 is formed such that a plurality of convex portions 210 provided on the peripheral surface of the concave-convex roll 21 and a plurality of concave portions 220 provided on the peripheral surface of the concave-convex roll 22 mesh with each other. The plurality of convex portions 210 are arranged uniformly and regularly in the rotation axis direction and the circumferential direction of the concave-convex roll 21, respectively. The partial stretch processing unit 200 includes transport rolls 24 and 25 that transport the raw material nonwoven fabric 51M on the upstream side and the downstream side of the steel matching embossing roller 23.

It is preferable that each convex part 210 of the uneven | corrugated roll 21 is 1-10 mm in height from the surrounding surface of the uneven | corrugated roll 21 to the vertex of the convex part 210, and it is still more preferable that it is 2-7 mm. The distance (pitch) between the protrusions 210 adjacent to each other in the rotation axis direction is preferably 0.01 to 20 mm, more preferably 1 to 10 mm, and the distance between the protrusions 210 adjacent in the circumferential direction ( The pitch) is preferably 0.01 to 20 mm, and more preferably 1 to 10 mm. There is no restriction | limiting in particular in the shape of the top surface of each convex part 210 of the uneven | corrugated roll 21, For example, circular, a polygon, an ellipse etc. are used, The area of the top surface of each convex part 210 is 0.01-500 mm < ² >. It is preferable that it is 0.1-10 mm < ² >. Each concave portion 220 of the concave / convex roll 22 is disposed at a position corresponding to each convex portion 210 of the concave / convex roll 21. The depth of engagement between the convex portions 210 of the concave-convex roll 21 and the concave portions 220 of the concave-convex roll 22 (the length of the portion where the convex portions 210 and the concave portions 220 overlap) is 0.1 to 10 mm. It is preferable that it is 1-5 mm, and it is still more preferable.

  As shown in FIGS. 3 and 5, the raised portion 300 includes a convex roll 31 having a convex portion 310 provided on the peripheral surface, and conveys the raw material nonwoven fabric 51 </ b> M to the upstream side and the downstream side of the convex roll 31. Rolls 32 and 33 are provided. The convex roll 31 rotates when a driving force from a driving means (not shown) is transmitted to its rotating shaft.

Each convex portion 310 of the convex roll 31 preferably has a height from the peripheral surface of the convex roll 31 to the apex of the convex portion 310 of 0.001 to 3 mm, and preferably 0.001 to 0.1 mm. Further preferred. The distance (pitch) between the protrusions 310 adjacent to each other in the rotation axis direction is preferably 0.1 to 50 mm, more preferably 0.1 to 3 mm, and the distance between the protrusions 310 adjacent to each other in the circumferential direction. The distance (pitch) is preferably 0.1 to 50 mm, and more preferably 0.1 to 3 mm. There is no restriction | limiting in particular in the shape of the top surface of each convex part 310 of the convex roll 31, For example, circular, a polygon, an ellipse etc. are used, The area of the top surface of each convex part 310 is 0.001-20 mm < ² >. It is preferable that it is 0.01-1 mm < ² >.

A method for manufacturing the outer layer sheet 51 subjected to the raising process using the processing apparatus 100 including the partial stretching unit 200 and the raising unit 300 having the above-described configuration will be described.
First, the raw material nonwoven fabric 51M of the spunbond nonwoven fabric of the outer layer sheet 51 is unwound, and between the pair of concave and convex rolls 21 and 22 of the steel matching embossing roller 23 provided with the raw material nonwoven fabric 51M in the partially stretched processing unit 200 by the transport rolls 24 and 25. Transport to. And raw material nonwoven fabric 51M is pinched between a pair of uneven | corrugated rolls 21 and 22, and the raw material nonwoven fabric 51M is damaged.

  Next, the damaged raw material nonwoven fabric 51M ′ is transported by the transport rolls 32 and 33 to the convex roll 31 included in the raised processing unit 300. In the raised processing portion 300, the surface of the damaged raw material nonwoven fabric 51M ′ is processed by the convex roll 31, and a part of the long fibers constituting the spunbonded nonwoven fabric is broken, and only one end portion of the long fibers is broken. The outer layer sheet 51 subjected to the raising treatment having the raising fibers fixed by the heat-sealed portion of the spunbond nonwoven fabric can be manufactured (see FIG. 3).

  The spunbonded nonwoven fabric of the outer layer sheet 51 is formed by kneading a softener or applying a softener to the constituent fibers from the viewpoint of good touch, low surface friction and improved flexibility. Preferably it is. The softener preferably contains at least one of a surfactant and paraffin oil. Moreover, you may add a well-known chemical | medical agent to a softening agent as a secondary additive (small component) as needed. Moreover, you may add a lubricant to a softener as needed.

  As surfactants, carboxylate anionic surfactants, sulfonate anionic surfactants, sulfate ester anionic surfactants, phosphate ester anionic surfactants (especially alkyl phosphates). Acid ester salts) and the like; polyhydric alcohol monofatty acid esters such as sorbitan fatty acid ester, diethylene glycol monostearate, diethylene glycol monooleate, glyceryl monostearate, glyceryl monooleate, propylene glycol monostearate, N- (3-oleyloxy-2-hydroxypropyl) diethanolamine, polyoxyethylene hydrogenated castor oil, polyoxyethylene sorbit beeswax, polyoxyethylene sorbitan sesquistearate, polyoxyethylene monooleate Such as polyoxyethylene sorbitan sesquistearate, polyoxyethylene glyceryl monooleate, polyoxyethylene monostearate, polyoxyethylene monolaurate, polyoxyethylene monooleate, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, Nonionic surfactants: Cationic surfactants such as quaternary ammonium salts, amine salts or amines; aliphatic derivatives of secondary or tertiary amines containing carboxy, sulfonate, sulfate, or heterocyclic Zwitterionic surfactants such as aliphatic derivatives of secondary or tertiary amines can be used.

  As various oils such as paraffin oil, the kinematic viscosity at 40 ° C. is preferably 20 cst (centistokes) or more and 800 cst or less, and more preferably 40 cst or more and 600 cst or less. Further, the fluidity of the oil is preferably 0 ° C. or higher and −40 ° C. or lower, more preferably 0 ° C. or higher and −30 ° C. or lower, and the flash point (COC method) is 200 ° C. or higher and 400 ° C. or lower. It is more preferable that it is 250 degreeC or more and 350 degrees C or less.

  As the lubricant, oleic acid amide, erucic acid amide, stearic acid amide, and the like can be used.

  The spunbond nonwoven fabric of the outer layer sheet 51 is formed by stacking a plurality of spunbond nonwoven fabrics in addition to the shape of the spunbond nonwoven fabric alone. For example, a spunbond-spunbond-spunbond laminated nonwoven fabric, a spunbond-meltblown-spun The shape may be a bond laminated nonwoven fabric, a spunbond-spunbond-meltblown-spunbond laminated nonwoven fabric, or the like. In the case of the shape of the laminated nonwoven fabric, the softener is preferably kneaded only in one layer of spunbond nonwoven fabric, and may be kneaded in all layers of spunbond nonwoven fabric.

  In more detail regarding the ventral-side exterior body 5A and the back-side exterior body 5B in the diaper 1, the fiber orientation directions of the fibers constituting the outer layer sheet 51 and the inner layer sheet 52 in the disposable diaper 1 are as shown in FIG. The same direction as the lateral direction (Y direction) of the diaper 1. Each of the ventral exterior body 5A and the back exterior body 5B has a partial joining region JT in which the outer layer sheet 51 and the inner layer sheet 52 are partially joined outside the absorbent main body 10. Yes. The partial bonding region JT of the diaper 1 includes a plurality of outer body fusions obtained by intermittently joining the outer layer sheet 51 and the inner layer sheet 52 by thermal fusion in the horizontal direction (Y direction) and the vertical direction (X direction). The portion 54 is formed. In the partial joint region JT, the plurality of elastic members 53 are arranged in an extended state in the lateral direction (Y direction) so as not to pass through the plurality of exterior body fusion portions 54, and the elastic members 53 arranged in the extended state are arranged. Both end portions are fixed between the outer layer sheet 51 and the inner layer sheet 52, and each of the outer layer sheet 51 and the inner layer sheet 52 continuously extends over the plurality of elastic members 53. Is forming. This will be specifically described below.

  The exterior body 5 of the diaper 1 is provided with a stretchable part having stretchability in the lateral direction (Y direction) of the diaper 1. Specifically, the partial joint region JT of the ventral-side exterior body 5A and the back-side exterior body 5B of the diaper 1 is formed outward from the absorbent main body 10, and the longitudinal direction (X direction) of the absorbent main body 10 ) In the lateral direction (Y) than the positions of the waist stretchable part G1 formed outward in the X direction from both ends 10a and 10b and the side edges 10s and 10s along the longitudinal direction (X direction) of the absorbent main body 10. (Direction) It has the waist expansion-contraction part G2, G2 which is located outside and is located in the crotch part C side from the waist expansion-contraction part G1 and above the lower end of the side seal part S. That is, in this embodiment, the partial joining area | region JT is provided with the expansion-contraction part which has a stretching property in a horizontal direction (Y direction), and this expansion / contraction part has the waist expansion-contraction part G1 and the trunk periphery expansion-contraction part G2. In the waist stretchable part G1 and the waistline stretchable part G2, the space between the outer layer sheet 51 and the inner layer sheet 52 is intermittently arranged in the form of dots in the horizontal direction (Y direction) and the vertical direction (X direction). Joined at a large number of exterior body fusion portions 54.

As shown in FIG. 2, an outer body fusion part 54 in which an outer layer sheet 51 and an inner layer sheet 52 are fused is formed on the waist stretchable part G <b> 1 of each of the belly side exterior body 5 </ b> A and the back side exterior body 5 </ b> B of the diaper 1. Are formed intermittently so as to form a line along the X direction, and a plurality of rows of fusion part 54S composed of the plurality of exterior body fusion parts 54 are formed at intervals in the Y direction. .
Further, the outer body fusion part 54 in which the outer layer sheet 51 and the inner layer sheet 52 are fused also forms a line along the X direction in the waistline stretchable part G2 in each of the abdominal side outer body 5A and the back side outer body 5B. Thus, a plurality of rows of fusion-bonded portions 54P formed of a plurality of exterior body fusion portions 54 are formed at intervals in the Y direction.
In each of the belly side exterior body 5A and the back side exterior body 5B of the diaper 1, the fused portion row 54S of the waist stretchable portion G1 and the fused portion row 54P of the waistline stretchable portion G2 are arranged in a row continuous in the X direction. Forming.
In a state where the diaper 1 is unfolded and stretched, the interval between the fusion portion rows 54S and 54S adjacent in the lateral direction (Y direction) (interval between the fusion portion rows 54P and 54P) is a low-stiffness spunbond nonwoven fabric. However, from the viewpoint of easily forming a flange 57 to be described later and improving the operability by increasing the rigidity in the vertical direction (X direction), it is preferably 1 mm or more and 20 mm or less, and preferably 3 mm or more and 10 mm or less. Further preferred.

In the waist expansion / contraction part G1 of the diaper 1, the position in the X direction of each of the plurality of exterior body fusion parts 54 constituting one fusion part row 54S and another adjacent to the one fusion part row 54S. The positions in the X direction of the plurality of exterior body fusion parts 54 constituting the fusion part row 54S substantially coincide with each other. The plurality of elastic members 53 are arranged so as to extend in the Y direction through the gaps between the outer package fusion parts 54 and 54 of the plurality of fusion part rows 54S, respectively. The plurality of elastic members 53 are all disposed between the outer layer sheet 51 and the inner layer sheet 52.
Similarly, in the waistline expansion and contraction portions G2 and G2, the positions in the X direction of the plurality of exterior body fusion portions 54 constituting one fusion portion row 54P are adjacent to the one fusion portion row 54P. The position in the X direction of each of the plurality of outer package fusion parts 54 constituting another fusion part row 54P substantially matches. The plurality of elastic members 53 are arranged so as to extend in the Y direction through the gaps between the outer package fusion parts 54 and 54 of the plurality of fusion part rows 54P, respectively. The plurality of elastic members 53 are all arranged between the outer layer sheet 51 and the inner layer sheet 52.

In the diaper 1 of the present embodiment, as shown in FIG. 2, the abdominal exterior body 5 </ b> A and the back exterior body 5 </ b> B are both outer layer sheet 51 and inner layer sheet 52 on both outer edges along the X direction. Between the outer layer sheet 51 and the inner layer sheet 52 in the vicinity of the position of the side edge 10 s of the absorbent main body 10. It has a main body side fixing region 56 joined through an adhesive.
A plurality of elastic members 53 are arranged between the pair of outer fixing regions 55 in the waist stretchable part G1, and these elastic members 53 are separated from the outer layer sheet 51 and the inner layer in each of the pair of outer fixing regions 55. It is fixed between the sheet 52. On the other hand, between the outer fixed regions 55, the elastic member 53 is not fixed to either the outer layer sheet 51 or the inner layer sheet 52.
On the other hand, a plurality of elastic members 53 are arranged between the outer fixed region 55 and the main body side fixed region 56 in the waistline expansion / contraction part G2, and these elastic members 53 are connected to the outer fixed region 55. Each of the main body side fixing regions 56 is fixed between the outer layer sheet 51 and the inner layer sheet 52. On the other hand, the elastic member 53 is not fixed to either the outer layer sheet 51 or the inner layer sheet 52 between the outer fixed region 55 and the main body side fixed region 56. It should be noted that the elastic member 53 is not disposed between the pair of main body side fixing regions 56, 56 or is disposed in a state in which the elastic member 53 is subjected to a process for preventing elastic elasticity such as cutting. Has been.

  As shown in FIG. 2, the main body-side fixing region 56 may be formed so as to entirely overlap the absorbent main body 10, but is formed so as to straddle the inside and outside of the side edge 10 s of the absorbent main body 10. May be. The main body side fixing region 56 may be formed outward in the lateral direction (Y direction) from the side edge 10 s of the absorbent main body 10. In addition, in the aspect in which the entire main body side fixing region 56 overlaps the absorbent main body 10, the position of the edge on the outer side in the lateral direction (Y direction) of the main body side fixing region 56 and the side edge 10 s of the absorbent main body 10. Both the aspect in which a position corresponds and the aspect in which the main body side fixing region 56 is formed with a predetermined interval between the side edge 10s of the absorbent main body 10 are included.

  As shown in FIG. 6, the plurality of exterior body fusion parts 54 constituting the fusion part rows 54 </ b> S and 54 </ b> P described above are all arranged in the X direction with a gap m therebetween as shown in FIG. 6. It consists of a pair of fusion parts u and d. In the diaper 1, the outer body fusion part 54 has a planar view shape (overall shape including the gap m) orthogonal to the fiber orientation direction (the same direction as the lateral direction (Y direction) in the disposable diaper 1). It is a rectangular shape that is long in the (X direction). The exterior body fusion portion 54 has a length L1 in the X direction from the viewpoint of forming a plurality of ridges 57 extending continuously across the plurality of elastic members 53 and improving the flexibility of the exterior body 5 in the X direction. However, the length L2 in the Y direction is preferably 2 times or more, more preferably 7 times or more, and preferably 10 times or less, more preferably 9 times or less. Specifically, the length L1 in the X direction of the outer package fusion part 54 is preferably 1 mm or more and 8 mm or less, preferably 1 mm or more and 5 mm or less from the viewpoint of maintaining the characteristics of the flexible and flexible spunbonded nonwoven fabric. More preferably it is.

  Moreover, it is preferable that the individual fused parts u and d constituting the outer package fused part 54 also have a long shape in the X direction. The individual fused portions u and d have a length L3 in the X direction that is a length L4 in the Y direction (length) due to the formability of the plurality of flanges 57 that continuously extend over the plurality of elastic members 53. L2) is preferably 1 time or more, more preferably 2 times or more, and preferably 4 times or less, more preferably 5 times or less.

  The length L5 of the gap m of the outer package fusion part 54 (see FIG. 6, the distance between the fusion parts u and d) is the distance between the outer package fusion parts 54 and 54 adjacent in the X direction. It is preferable that it is less than L6. By setting the length L5 of the gap m to be less than the distance L6, the flexibility of the flange 57 due to the fact that the elastic member 53 is not firmly fixed between the outer body fusion parts 54 and 54, and between the fusion part rows In addition, it is easy to achieve compatibility with the formability of the flange 57 that intersects the elastic member 53 and extends continuously in the X direction. From the same viewpoint, the ratio of the length L5 to the distance L6 is preferably 40% or less, more preferably 35% or less, and preferably 25% or more, more preferably 30% or more.

  Further, the ratio (L1 / L7) of the length L1 in the X direction of the outer package fusion part 54 to the distance L7 (see FIG. 6) between the elastic members 53 adjacent to each other in the X direction (L1 / L7) is the stretchability of the elastic member 53. From the viewpoint of making it difficult to prevent the mark of the elastic member 53 from being attached to the wearer's skin, it is preferably 0.1 or more and 0.8 or less, and more preferably 0.2 or more and 0.6 or less. Specifically, the distance L7 between the elastic members 53 adjacent to each other in the X direction is preferably 4 mm or more and 12 mm or less, and more preferably 5 mm or more and 10 mm or less.

  The outer package fusion part 54 is formed by overlapping the outer layer sheet 51 and the inner layer sheet 52 and subjecting the part to hot embossing. As the heat embossing device, an embossing roll and an anvil roll are provided, and an embossing roll having a convex portion having a shape corresponding to the fusion parts u and d of the outer body fusion part 54 is used on the outer peripheral surface of the embossing roll. it can. As a process for forming the outer package fusion part 54, an ultrasonic seal, a laser, or the like can be employed instead of the heat embossing process.

  The side seal portion S described above is formed by overlapping the body-side fixing region 56 on the abdominal side A side and the body-side fixing region 56 on the back side B side after the formation of the outer body fused portion 54. It is formed by subjecting to hot embossing. In addition, as a process for forming the side seal portion S, an ultrasonic seal, a laser, an adhesive, or the like can be employed instead of the heat embossing process.

In the waist stretchable part G1 of the diaper 1, as shown in FIG. 7, the elastic member 53 disposed in an extended state in the lateral direction (Y direction) between the outer layer sheet 51 and the inner layer sheet 52 contracts, The outer layer sheet 51 and the inner layer sheet 52 between the adjacent fusion part rows 54S are deformed so as to swell outward in the thickness direction, and the outer layer sheet 51 or the inner layer sheets 52, 51R are formed between the adjacent fusion part rows 54S. 57 is generated, and a hollow portion 58 surrounded by the flange 57 and the flange 57 is formed between the sheets 51 and 52.
In the diaper 1, the sheet material constituting the outer layer sheet 51 in each of the abdominal exterior body 5A and the back exterior body 5B is folded back to the skin contact surface side of the inner layer sheet 52 along the periphery of the waist opening WO. The folded portion 51R covers the skin contact surface side of the inner layer sheet 52 in the waist stretchable part G1 (see FIG. 7). Further, the folded portion 51R is joined to the skin contact surface of the inner layer sheet 52 and / or the absorbent main body 3 by an adhesive that is applied entirely or partially, while the folded portion 51R is bonded to the outer body fusion portion 54. Is not fused.

  In the waistline elastic part G2, as shown in FIG. 8, the elastic member 53 disposed in an extended state in the lateral direction (Y direction) is contracted between the outer layer sheet 51 and the inner layer sheet 52, so The outer layer sheet 51 and the inner layer sheet 52 between the attachment part rows 54P are deformed so as to swell outward in the thickness direction, and a ridge 57 composed of the outer layer sheet 51 or the inner layer sheets 52, 51R is generated between the adjacent fusion part rows 54P. At the same time, a hollow portion 58 is formed between the sheets 51 and 52 and is surrounded by the flanges 57 and 57.

  In each of the ventral-side exterior body 5A and the back-side exterior body 5B of the diaper 1, a collar 57 of the waist stretchable part G1 and a collar 57 of the waistline stretchable part G2 are formed continuously in the X direction. Further, in each of the ventral exterior body 5A and the back exterior body 5B of the diaper 1, the hollow portion 58 of the waist stretchable portion G1 and the hollow portion 58 of the waistline stretchable portion G2 are continuously formed in the X direction. Yes. As described above, the plurality of ridges 57 continuously extend over the elastic members 53 extending in the plurality of lateral directions (Y directions).

  In the diaper 1 configured as described above, as described above, the exterior body 5 includes the outer layer sheet 51 and the inner layer sheet 52, and includes a stretchable portion having stretchability in the lateral direction (Y direction). The stretchable part has a waist stretchable part G1 and a waistline stretchable part G2. The said expansion-contraction part in the exterior body 5 of the diaper 1 satisfy | fills all the following requirements (I)-requirements (III). This will be specifically described below.

The stretchable part in the outer package 5 of the diaper 1 has an average deviation SMD ₂ (requirement (I)) of the surface roughness of 6.0 μm or less from the viewpoint of improving the touch of the diaper 1, and 5.5 μm or less. It is preferable that it is 5.0 μm or less. In addition, as a lower limit value of the average deviation SMD ₂ of the surface roughness of the stretchable part, it is preferable that it is closer to 0, but if it is 0.5 μm or more, sufficient smoothness is imparted to the outer package 5 of the diaper 1. Is done. The average deviation SMD ₂ of the surface roughness of the stretchable part in the exterior body 5 is the same as the average deviation SMD of the surface roughness of the spunbonded nonwoven fabric of the outer layer sheet 51 described above, KESFB4-AUTO-A manufactured by Kato Tech Co., Ltd. Measured using (trade name). Specifically, it is measured by the following method.

[Measurement method of average deviation SMD ₂ of surface roughness of stretchable part in exterior body]
In the disposable diaper's belly-side exterior body, that is, in the diaper 1, 3.5 cm in the longitudinal direction (X direction) at the waist stretchable part G1 and the waistline stretchable part G2 in the natural-side stomach-side exterior body 5A. The measurement piece is cut into a rectangular shape that is as long as possible in the lateral direction (Y direction). The cut measurement piece is used as a measurement sample. In a state where the measurement sample is stretched 100% in the lateral direction (Y direction), the measurement sample is attached to a smooth metal flat test stand so that the outer layer sheet 51 side of the measurement sample becomes the measurement surface. The contact is pressed against the measurement sample at 9.8 cN (within ± 0.49 cN error). The measurement sample is moved 2 cm in the vertical direction (X direction) at a constant speed of 0.1 cm / sec. A uniaxial tension of 19.6 cN / cm is applied to the measurement sample. The contact is made of a 0.5 mm diameter piano wire bent in a U shape with a width of 5 mm, and a measurement sample is pressure-bonded at 9.8 cN. The contact is crimped with a spring. The spring constant is 24.5 cN / mm (within an error of ± 0.98 cN / mm), and the resonance frequency is 30 Hz or more in a state away from the surface contact. The measured value of the average deviation of the surface roughness of the stretchable part in the exterior body is represented by the SMD _binary value. This measurement is performed longitudinal direction (X direction) only three times, by averaging values, this is the mean deviation SMD ₂ of the surface roughness of the elastic portion in the outer package.

  The said expansion-contraction part in the exterior body 5 of the diaper 1 is the compression rate (requirement (II)) by the KES compression tester from a viewpoint of the improvement of the touch of the diaper 1, and is 73% or more. Preferably, it is 75% or more. The compression ratio measured by the KES compression tester means that the larger the value is, the better the cushioning property is. However, if the upper limit value of the compression ratio is 95% or less, it is a diaper. A sufficient cushion feeling is imparted to one exterior body 5. The compressibility of the stretchable part of the outer package 5 by a KES compression tester is specifically measured by the following method.

[Method of measuring compressibility of stretchable part of exterior body with KES compression tester]
In the disposable diaper's belly-side exterior body, that is, in the diaper 1, 3.5 cm in the longitudinal direction (X direction) at the waist stretchable part G1 and the waistline stretchable part G2 in the natural-side stomach-side exterior body 5A. The measurement piece is cut into a rectangular shape that is as long as possible in the lateral direction (Y direction). The cut measurement piece is used as a measurement sample. In a state where the measurement sample is stretched by 70% in the lateral direction (Y direction), the measurement sample is attached to a smooth metal flat test stand so that the outer layer sheet 51 side of the measurement sample becomes the measurement surface. As the measuring apparatus, using a KES-FB3 compression tester manufactured by Kato Tech Co., to measure the thickness _{T 0} under 0.5 gf / cm ² load measurement sample in the compressed area 2 cm ^2. Next, the sample is compressed at a pressing speed of 20 μm / second. The load increases with compression. Compression is performed until the load reaches 50 gf / cm ² . Then, to measure the thickness _{T m} of a under 50 gf / cm ² load. The value obtained by subtracting the thickness _{T m} from the thickness _{T 0} divided by the thickness _{T 0,} is calculated compression ratio by KES compression testing machine (%) in this by multiplying by 100. That is, the compression rate (%) is calculated from ((T ₀ −T _m ) / T ₀ ) × 100.

  The stretchable part in the outer package 5 of the diaper 1 has a compression recovery rate (requirement (III)) by the KES compression tester of 40% or less and 39% or less from the viewpoint of improving the touch of the diaper 1. Is preferable, and it is still more preferable that it is 38% or less. In addition, as a lower limit of the compression recovery rate by a KES compression tester, if it is 30% or more, sufficient compression softness is provided to the exterior body 5 of the diaper 1. The compression recovery rate of the stretchable part in the outer package 5 is specifically measured by the following method using a KES compression tester.

[Measurement method of compression recovery rate of expansion / contraction part of exterior body with KES compression tester]
In the disposable diaper's belly-side exterior body, that is, in the diaper 1, 3.5 cm in the longitudinal direction (X direction) at the waist stretchable part G1 and the waistline stretchable part G2 in the natural-side stomach-side exterior body 5A. The measurement piece is cut into a rectangular shape that is as long as possible in the lateral direction (Y direction). The cut measurement piece is used as a measurement sample. In a state where the measurement sample is stretched by 70% in the lateral direction (Y direction), the measurement sample is attached to a smooth metal flat test stand so that the outer layer sheet 51 side of the measurement sample becomes the measurement surface. Using a handy compression tester (KES-G5) manufactured by Kato Tech Co., Ltd. as the measuring device, the compression work when the measurement sample is compressed to a maximum load of 50 gf / cm ² at a compression speed of 0.02 mm / sec. (A) Then, the compression recovery rate (%) is calculated by the following equation (3) from the recovery work (b) when the pressure is removed at the same speed and the load becomes zero.
Compression recovery rate = (b / a) × 100 (%) (3)

The formation material of each part of the disposable diaper 1 mentioned above is demonstrated.
As the surface sheet 2, the back sheet 3, the absorbent body 4, the side cuff 6 and the like constituting the absorbent main body 10, various kinds of materials conventionally used for absorbent articles such as disposable diapers are used without particular limitation. Can do. For example, as the surface sheet 2, a single layer or multilayer nonwoven fabric, an apertured film, or the like can be used. As the back sheet 3, a moisture-permeable resin film or the like can be used. As the absorbent body 4, an absorbent core made of absorbent polymer particles and a fiber material and covered with tissue paper can be used. Moreover, as the side cuff 6, a water-repellent single layer or multilayer nonwoven fabric or the like can be used.

  As the inner layer sheet 52 constituting the abdominal outer body 5A and the back outer body 5B of the outer body 5, the same sheet material (spunbond nonwoven fabric) as the outer layer sheet 51 described above can be used, but a different sheet material is used. May be. As the inner layer sheet 52 different from the outer layer sheet 51, a single layer nonwoven fabric or a laminated nonwoven fabric of two or more layers made of an air-through nonwoven fabric, a heat roll nonwoven fabric, a spunlace nonwoven fabric, a melt blown nonwoven fabric or the like is used particularly from the viewpoint of flexibility and the like. Can do.

Examples of elastic members (three-dimensional gather forming elastic member 61, elastic member 53, etc.) include synthetic rubbers such as styrene-butadiene, butadiene, isoprene, and neoprene, natural rubber, EVA, stretchable polyolefin, and polyurethane. it can. As a form of the elastic member, a cross-sectionally rectangular, square, circular, elliptical or polygonal thread shape (thread rubber or the like), a string shape (flat rubber etc.), or a multifilament type thread shape or the like It can be preferably used.
As the adhesive for forming the outer fixing area 55 and the main body side fixing area 56 for fixing each member, various hot melt adhesives conventionally used for absorbent articles such as disposable diapers are used without particular limitation. Can do.

The effect at the time of using the underpants type disposable diaper 1 mentioned above is demonstrated.
The disposable diaper 1 is a nonwoven fabric in which the outer layer sheet 51 forming the outer surface of the diaper 1 shown in FIG. 1 is formed from a spunbond nonwoven fabric, and the spunbond nonwoven fabric satisfies all the requirements (1) to (4). Specifically, since the basis weight of the spunbonded nonwoven fabric satisfies the requirement (1) that it is 18 g / m ² or less, the rigidity is low and the cost can be reduced. Further, the requirement (2) and requirement (3) that the average deviation SMD of the surface roughness of the spunbonded nonwoven fabric is 3.20 μm or less and the average deviation MMD of the friction coefficient of the spunbonded nonwoven fabric is 0.0085 or less. ), The smoothness of the nonwoven fabric is improved. Moreover, since the requirement (4) that the MD bulk softness of the spunbonded nonwoven fabric is 5.0 cN or less is satisfied, the drapeability of the nonwoven fabric is improved. Therefore, since the spunbonded nonwoven fabric constituting the outer layer sheet 51 is a nonwoven fabric that satisfies all the requirements (1) to (4), it is a nonwoven fabric having low rigidity and improved cloth-like properties. Therefore, the disposable diaper 1 using such a spunbonded nonwoven fabric for the outer layer sheet 51 has a good touch and can reduce the cost. Moreover, in the diaper 1 mentioned above, since the compression characteristic value at the time of a micro load of the spunbond nonwoven fabric satisfies the requirement (5) of 15.0 (gf / cm ² ) / mm or less, the nonwoven fabric is soft. The feeling is improving. Therefore, since the spunbonded nonwoven fabric constituting the outer layer sheet 51 is a nonwoven fabric that satisfies all the requirements (1) to (5), the nonwoven fabric has low rigidity and improved cloth-like properties. Therefore, the disposable diaper 1 using such a spunbonded nonwoven fabric for the outer layer sheet 51 has a good touch and can reduce the cost.

  In the disposable diaper 1, as shown in FIG. 2, the abdominal exterior body 5 </ b> A and the back exterior body 5 </ b> B are partially outside the absorbent main body 10, and the outer layer sheet 51 and the inner layer sheet 52 are partially formed. And a partial joint region JT joined to each other. When the diaper 1 having the partial joining region JT is worn, the abdominal exterior body 5A and the back exterior body 5B are soft and air permeability is improved, so that the quality of the product is further improved.

  As shown in FIGS. 7 and 8, the disposable diaper 1 includes a plurality of ridges 57 extending in a plurality of lateral directions (Y directions) in each of the abdominal exterior body 5A and the back exterior body 5B. It extends continuously over the elastic member 53, and when the diaper 1 is worn, the hollow portion 58 of the waist stretchable portion G1 and the hollow portion 58 of the waistline stretchable portion G2 are formed continuously in the X direction. become. Therefore, when the diaper 1 is worn, the air permeability is good, the trace of the elastic member 53 is hardly attached to the wearer's skin, and the quality of the product is further improved.

  The disposable diaper 1 is, as shown in FIGS. 2 and 6, the outer body fusion part 54 arranged in each of the abdominal outer body 5 </ b> A and the back outer body 5 </ b> B has a rectangular shape that is long in the X direction, A plurality of fused portion rows 54S of the waist stretchable portion G1 extending in the X direction and a fused portion row 54P of the waistline stretchable portion G2 are formed at substantially equal intervals in the lateral direction (Y direction). Therefore, it is easy to form a plurality of flanges 57 extending continuously over the plurality of elastic members 53, and the hollow portion 58 of the waist stretchable portion G1 and the hollow portion 58 of the waistline stretchable portion G2 are continuous in the X direction. If it becomes easy to form and the diaper 1 is worn, the air permeability is further improved, and the trace of the elastic member 53 is more difficult to adhere to the wearer's skin. Further, the outer package fusion part 54 has a long rectangular shape in the direction (X direction) orthogonal to the orientation direction of the fibers constituting the outer layer sheet 51 and the inner layer sheet 52 that form the ventral outer package 5A and the back outer package 5B. It is. Therefore, the strength in the direction (X direction) orthogonal to the orientation direction of the fibers constituting each of the outer layer sheet 51 and the inner layer sheet 52 is reinforced, and it becomes difficult to tear when wearing the diaper 1, thereby further improving the quality of the product. .

In the disposable diaper 1, the stretchable parts (the waist stretchable part G1 and the waistline stretchable part G2) in the outer package 5 of the diaper 1 shown in FIG. 2 satisfy all the requirements (I) to (III). Specifically, the stretchable part in the outer package 5 has a requirement (I) that the average deviation SMD ₂ of the surface roughness is 6.0 μm or less, and the compression ratio by the KES compression tester is 70% or more. Since the requirement (II) and the requirement (III) that the compression recovery rate by the KES compression tester is 40% or less are all satisfied, the touch of the exterior body 5 of the diaper 1 is good.

As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to embodiment mentioned above, It can change suitably.
For example, the disposable diaper 1 is a split-type pants type in which the exterior body 5 is divided into a ventral exterior body 5A, a back exterior body 5B, and a crotch exterior body 5C as separate members as shown in FIGS. Although it is a disposable diaper, the exterior body may be an exterior body having a continuous shape such as an hourglass shape extending over the ventral region A, the crotch region C, and the back region B. Specifically, each of the outer layer sheet 51 and the inner layer sheet 52 constituting the exterior body is composed of one sheet continuous from the ventral region A to the dorsal region B, and between these two sheets 51 and 52. A pants-type disposable diaper using an exterior body formed by fixing a plurality of elastic members 53 may be used. In such a pants-type disposable diaper, the outer layer sheet 51 is a spunbonded nonwoven fabric. Moreover, the elastic body 53 is not provided, and the exterior body 5 is made of a single sheet material, and the single sheet material has a continuous shape such as an hourglass shape extending over the ventral region A, the crotch region C, and the dorsal region B. A deployment type in which a pair of fastening tapes are provided on the left and right side edges of the back side portion B, and a landing tape for fastening the fastening tape is provided on the non-skin facing surface of the abdominal side portion A. It may be a disposable diaper. In the case of such a deployable disposable diaper, the one sheet material is a spunbond nonwoven fabric. The exterior body 5 is made of a single sheet material, and the single sheet material is formed in a continuous shape such as a rectangular shape extending over the ventral region A, the crotch region C, and the dorsal region B. A deployable disposable diaper in which side panels extending laterally outward are attached to the left and right side edges of the part B, and a fastening tape is attached to the laterally outward side of the side panel may be used. . In the case of such a deployable disposable diaper, the one sheet material is a spunbond nonwoven fabric.

  Further, as shown in FIG. 2, the abdominal-side exterior body 5A and the back-side exterior body 5B constituting the exterior body 5 of the disposable diaper 1 have a partial joining region JT that heat-seal the outer-layer sheet 51 and the inner-layer sheet 52. The outer layer sheet 51 and the inner layer sheet 52 are intermittently bonded with an adhesive in the horizontal direction (Y direction) and the vertical direction (X direction). May be formed.

  Further, as shown in FIG. 2, the abdominal exterior body 5 </ b> A and the back exterior body 5 </ b> B constituting the exterior body 5 of the disposable diaper 1 are configured so that the exterior body fusion portion 54 has a shape in plan view (the whole including the gap m). The shape is a rectangular shape that is long in the direction (X direction) perpendicular to the fiber orientation direction, but may be other shapes. Further, as shown in FIGS. 2 and 6, the outer package fusion part 54 is formed of a pair of fusion parts u and d that are arranged in the X direction with a gap m therebetween. It may be formed from one fusion part.

  The following disposable diaper is further disclosed regarding the embodiment mentioned above.

<1>
A disposable diaper comprising a top sheet, a back sheet, a vertically long absorbent main body provided with an absorbent body disposed between both sheets, and an exterior body disposed on the non-skin facing surface side of the absorbent main body. And
The exterior body has an outer layer sheet that forms an outer surface of the disposable diaper, and the outer layer sheet is made of a spunbond nonwoven fabric,
The spunbonded nonwoven fabric has a basis weight of 19 g / m ² or less, an average deviation SMD of the surface roughness of 3.20 μm or less, an average deviation MMD of the friction coefficient of 0.0085 or less, and an MD bulk softness. Disposable diaper whose is less than 5.0 cN.

<2>
The basis weight of the spunbonded nonwoven fabric is preferably 18 g / m ² or less, and the disposable diaper according to <1>, which is 10 g / m ² or more.
<3>
The spunbonded nonwoven fabric has an average deviation SMD of the surface roughness of 3.1 μm or less, preferably 3.0 μm or less, and the lower limit of the average deviation SMD is preferably closer to 0, more preferably 0. Disposable diaper as described in said <1> or <2> which is 0.5 micrometer or more.
<4>
In the spunbonded nonwoven fabric, the average deviation MMD of the friction coefficient is 0.0075 or less, and the lower limit value of the average deviation MMD is preferably closer to 0, more preferably 0.003 or more. The disposable diaper according to any one of to <3>.
<5>
The spunbonded nonwoven fabric has the MD bulk softness of 4.0 cN or less, preferably 3.5 cN or less. The lower limit of the MD bulk softness is preferably closer to 0, and more preferably is 0.00. The disposable diaper according to any one of <1> to <4>, which is 5 cN or more.
<6>
The spunbonded nonwoven fabric has a compressive characteristic value at the time of the minute load of 14.0 (gf / cm ² ) / mm or less, preferably 13.0 (gf / cm ² ) / mm or less. The lower limit value of the compression characteristic value is preferably closer to 0, more preferably 1.0 (gf / cm ² ) / mm or more, and the disposable according to any one of <1> to <5> Diapers.
<7>
<1> to <6>, wherein the spunbonded nonwoven fabric has a total area ratio (embossing rate) of a plurality of heat-bonding portions constituting the spunbonded nonwoven fabric that occupies the surface area of one surface thereof is 15% or less. The disposable diaper according to any one of the above.
<8>
The spunbonded nonwoven fabric has a total area ratio (embossing rate) of a plurality of heat-bonding portions constituting the spunbonded nonwoven fabric in the surface area of one surface of 5% to 13%, preferably 6% to 11%. The disposable diaper according to any one of <1> to <7>, which is the following.

<9>
The disposable diaper according to any one of <1> to <8>, wherein each of the plurality of heat-sealed portions constituting the spunbonded nonwoven fabric has an area of 0.3 mm ² or less.
<10>
Each of the plurality of heat-sealed portions constituting the spunbonded nonwoven fabric has an individual area of 0.1 mm ² or more and 0.25 mm ² or less, preferably 0.1 mm ² or more and 0.2 mm ² or less. The disposable diaper according to any one of <9>.
<11>
<1> to <10, wherein the spunbonded nonwoven fabric has 10 / cm ² or more and 250 / cm ² or less, preferably 35 / cm ² or more and 65 / cm ² or less of heat-bonded portions. > The disposable diaper of any one of>.
<12>
The spunbonded nonwoven fabric is a disposable diaper according to any one of the above <1> to <11>, which is subjected to raising treatment.
<13>
The disposable diaper according to any one of <1> to <12>, wherein the spunbonded nonwoven fabric contains at least one of a surfactant and paraffin oil as a softening agent.
<14>
The spunbond nonwoven fabric is the disposable diaper according to any one of <1> to <13>, wherein the content of crimped long fibers is 30% by mass or more and 100% by mass or less.
<15>
The spunbonded nonwoven fabric is a disposable diaper according to any one of <1> to <14>, wherein the compression characteristic value at the time of a minute load is 15.0 (gf / cm ² ) / mm or less.
<16>
The disposable diaper according to any one of <1> to <15>, wherein the spunbonded nonwoven fabric has a breaking strength in a direction perpendicular to the orientation direction of the constituent fibers of 7.0 N / 50 mm or more.
<17>
The exterior body has an abdominal exterior body disposed on the wearer's abdomen and a back exterior body disposed on the back side,
The ventral exterior body and the back exterior body are each configured to include the outer layer sheet and an inner layer sheet that is disposed on the inner surface side of the outer layer sheet and forms the inner surface of the disposable diaper,
The abdominal exterior body and the back exterior body each have a partially joined region where the outer layer sheet and the inner layer sheet are partially joined outside the absorbent main body. The disposable diaper according to any one of 1> to <16>.
<18>
The ventral exterior body and the back exterior body are each configured to include the outer layer sheet, the inner layer sheet, and a plurality of thread-like elastic members arranged between the sheets,
The partial joining region is formed by a plurality of exterior body fusion portions that are joined together by thermal fusion in the longitudinal direction and the lateral direction, the outer layer sheet and the inner layer sheet,
In the partial joining region, the plurality of elastic members are arranged in a laterally extended state so as not to pass through the plurality of exterior body fusion parts, and both ends of the elastic members arranged in the extended state are <17, wherein the outer layer sheet and the inner layer sheet are fixed between the outer layer sheet and the inner layer sheet, and each of the outer layer sheet and the inner layer sheet forms a plurality of ridges extending continuously over the plurality of elastic members. The disposable diaper described in>.
<19>
The ventral side exterior body and the back side exterior body have a waist stretchable part formed outward in the longitudinal direction from both ends in the longitudinal direction (X direction) of the absorbent main body,
In the waist stretchable portion, the outer body fusion portion where the outer layer sheet and the inner layer sheet are fused is intermittently formed in a row along the longitudinal direction (X direction), The disposable diaper according to the above <17> or <18>, wherein a plurality of rows of fusion-bonded portions including the outer-body fusion-bonded portions are formed at intervals in the lateral direction (Y direction).
<20>
The abdominal side exterior body and the back side exterior body have waistline elastic parts positioned outward in the lateral direction (Y direction) rather than the positions of both side edges along the longitudinal direction (X direction) of the absorbent main body 10. And
In the waistline stretchable part, the outer body fusion part in which the outer layer sheet and the inner layer sheet are fused is intermittently formed in a row along the vertical direction (X direction), The disposable diaper according to any one of the above items <17> to <19>, wherein a plurality of rows of fusion-bonded portions formed of body-fused portions are formed at intervals in the lateral direction (Y direction).

<21>
The disposable diaper according to <19> or <20>, wherein an interval between the fusion part rows adjacent in the horizontal direction (Y direction) is 1 mm or more and 20 mm or less, preferably 3 mm or more and 10 mm or less.
<22>
In the waist stretchable part, a plurality of elastic members are arranged across a pair of outer fixed regions,
The elastic member is fixed between the outer layer sheet and the inner layer sheet in each of the pair of outer fixed regions, and is fixed to both the outer layer sheet and the inner layer sheet between the outer fixed regions. The disposable diaper according to the above <19>.
<23>
The outer body fusion part has a length L1 in the longitudinal direction (X direction) of 2 times or more, preferably 7 times or more, and 10 times or less of the length L2 in the lateral direction (Y direction). The disposable diaper according to any one of <18> to <22>, which is preferably 9 times or less.
<24>
The disposable diaper according to any one of <18> to <23>, wherein a length L1 in the longitudinal direction (X direction) of the outer package fusion part is 1 mm or more and 8 mm or less, preferably 1 mm or more and 5 mm or less.
<25>
Each fusion part constituting the outer package fusion part has a length L3 in the longitudinal direction (X direction) of 1 or more times, preferably 2 or more times a length L4 in the lateral direction (Y direction). The disposable diaper according to any one of <18> to <24>, which is 4 times or less, preferably 5 times or less.
<26>
The length L5 of the gap between the individual fusion parts constituting the exterior body fusion part (the distance between the fusion parts constituting the exterior body fusion part) is adjacent to the longitudinal direction (X direction). The disposable diaper according to any one of the above items <18> to <25>, which is less than the distance L6 between the outer package fusion parts.
<27>
The ratio of the length L5 of the gap between the individual fusion parts constituting the exterior body fusion part to the distance L6 between the exterior body fusion parts adjacent in the longitudinal direction (X direction) is 40% or less. The disposable diaper according to any one of <18> to <26>, preferably 35% or less, and 25% or more, preferably 30% or more.
<28>
The ratio (L1 / L7) of the length L1 in the longitudinal direction (X direction) of the outer package fusion part to the distance L7 between the elastic members adjacent in the longitudinal direction (X direction) is 0.1 or more and 0.8. The disposable diaper according to any one of <18> to <27>, which is preferably 0.2 or more and 0.6 or less.
<29>
The disposable diaper according to any one of <18> to <28>, wherein an interval L7 between the elastic members adjacent to each other in the longitudinal direction (X direction) is 4 mm to 12 mm, preferably 5 mm to 10 mm.
<30>
The fiber orientation direction of the fibers constituting the outer layer sheet and the inner layer sheet is the same direction as the lateral direction of the disposable diaper,
The disposable diaper according to any one of <18> to <29>, wherein the outer package fusion part has a rectangular shape that is long in a direction orthogonal to the fiber orientation direction.

<31>
The disposable diaper according to any one of <17> to <30>, wherein the ventral-side exterior body and the back-side exterior body are configured as separate members.
<32>
The outer layer sheet is formed from the spunbond nonwoven fabric,
The disposable diaper according to any one of <17> to <31>, wherein the spunbonded nonwoven fabric of the outer layer sheet is formed from a propylene polymer that is a polyolefin polymer.
<33>
The disposable diaper according to <32>, wherein the propylene polymer is a propylene polymer having a molecular weight distribution (Mn / Mn) of 1.5 or more and 3.5 or less.
<34>
<32> or <33>, wherein the propylene-based polymer is made of a resin containing 5 to 100% by weight, preferably 25% to 80% by weight, of any one of a random copolymer, a homopolymer, and a block copolymer. Disposable diapers described in 1.
<35>
The propylene polymer is a polymer containing 5 to 100% by weight of an ethylene propylene random copolymer as a main component, preferably a polymer containing 25% by weight or more of an ethylene propylene random copolymer as a main component. The disposable diaper according to any one of <32> to <34>.
<36>
In the ethylene-propylene random copolymer, the ethylene content is 2.0 mol% or more and 10.0 mol% or less, preferably the ethylene content is 3.0 mol% or more and 8.0 mol% or less. Disposable diapers.
<37>
The disposable diaper according to any one of <1> to <36>, wherein the spunbond nonwoven fabric is a spunbond-spunbond-spunbond laminated nonwoven fabric (SSS laminated nonwoven fabric).
<38>
A vertically long absorbent main body provided with a top sheet, a back sheet, and an absorbent body disposed between the two sheets, and an exterior body disposed on the non-skin facing surface side of the absorbent body, Are divided into an abdominal side portion arranged on the wearer's ventral side, a dorsal side portion arranged on the dorsal side, and a crotch portion located between them. A pants-type disposable diaper in which a pair of side seal parts is formed by joining both side edges of the side part,
The exterior body includes an outer layer sheet that forms an outer surface of the pants-type disposable diaper, and an inner layer sheet that is disposed on the inner surface side of the outer layer sheet, and has a stretchable portion that is stretchable in a lateral direction of the pants-type disposable diaper. With
The stretchable part of the exterior body has an average surface roughness average deviation SMD ₂ of 6.0 μm or less, a compression rate of 70% or more by the KES compression tester, and a compression recovery rate of 40% or less by the KES compression tester. A pants-type disposable diaper.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited by the examples.

[Example 1]
Resin to be an ethylene-containing ethylene propylene random copolymer and erucic acid amide as a softener are supplied to an extruder and melt-kneaded, spun from a spinning nozzle hole, and spun long fibers are deposited on the collecting surface, Using a hot embossing roll, embossing was performed at an embossing rate of 9% (area of individual heat-sealed portions 0.18 mm ² ) to produce a spunbond nonwoven fabric having a basis weight of 17 g / m ² . The produced spunbonded nonwoven fabric was subjected to raising treatment using a processing apparatus 100 shown in FIG. With respect to the produced spunbond nonwoven fabric, the average deviation SMD of the surface roughness, the average deviation MMD of the friction coefficient, the MD bulk softness, and the compression characteristic value at a minute load were determined by the above-described measurement method, and are shown in Table 1. In addition, each convex part 210 in the uneven | corrugated roll 21 of the used steel matching embossing roller 23 is 2.8 mm in height, and mesh | engagement of each convex part 210 of the uneven | corrugated roll 21 and each recessed part 220 of the uneven | corrugated roll 22 is carried out. The depth was 2.7 mm. Moreover, the distance (pitch) between the convex parts 210 adjacent in the rotation axis direction was 7 mm, and the distance (pitch) between the convex parts 210 adjacent in the circumferential direction was 7 mm. Moreover, the height of each convex part 310 of the used convex roll 31 is 0.6 mm, and the distance (pitch) between the convex parts 310 adjacent to a rotating shaft direction is 1.4 mm, and is adjacent to the circumferential direction. The distance (pitch) between the convex portions 310 that fit each other was 2.1 mm.

[Example 2]
A polypropylene homopolymer and an ethylene propylene random copolymer are supplied to an extruder and melt-kneaded. After spinning from a spinning nozzle hole, cooling air is blown to develop crimps on the collecting surface. Then, using a hot embossing roll, an embossing treatment was performed at an embossing rate of 8% (individual heat-bonded portion area: 0.37 mm ² ) to produce a spunbonded nonwoven fabric having a basis weight of 18 g / m ² . With respect to the produced spunbond nonwoven fabric, the average deviation SMD of the surface roughness, the average deviation MMD of the friction coefficient, the MD bulk softness, and the compression characteristic value at a minute load were determined by the above-described measurement method, and are shown in Table 1.

[Example 3]
A resin to become an ethylene-containing ethylene-propylene random copolymer and paraffin oil as a softening agent are supplied to an extruder and melt-kneaded, spun from a spinning nozzle hole, and spun long fibers are deposited on a collecting surface, Using a hot embossing roll, embossing was performed at an embossing rate of 6.6% (area of individual heat-sealed portions 0.17 mm ² ) to produce a spunbond nonwoven fabric having a basis weight of 17 g / m ² . With respect to the produced spunbond nonwoven fabric, the average deviation SMD of the surface roughness, the average deviation MMD of the friction coefficient, the MD bulk softness, and the compression characteristic value at a minute load were determined by the above-described measurement method, and are shown in Table 1.

[Example 4]
A spunbond nonwoven fabric produced in the same manner as in Example 1 was not subjected to raising treatment and was designated as Example 4. With respect to the produced spunbond nonwoven fabric, the average deviation SMD of the surface roughness, the average deviation MMD of the friction coefficient, the MD bulk softness, and the compression characteristic value at a minute load were determined by the above-described measurement method, and are shown in Table 1.

[Comparative Example 1]
A spunbond nonwoven fabric having a basis weight of 17 g / m ² is produced in the same manner as in Example 3 except that the embossing is performed using a hot embossing roll at an embossing rate of 16% (individual heat-bonded portion area 0.31 mm ² ). did. With respect to the produced spunbond nonwoven fabric, the average deviation SMD of the surface roughness, the average deviation MMD of the friction coefficient, the MD bulk softness, and the compression characteristic value at a minute load were determined by the above-described measurement method, and are shown in Table 1.

[Comparative Example 2]
A spunbonded nonwoven fabric with a basis weight of 20 g / m ² was produced in the same manner as in Example 3 except that the embossing treatment was performed using a hot embossing roll at an embossing rate of 15% (area of each heat-sealed portion 0.72 mm ² ). did. With respect to the produced spunbond nonwoven fabric, the average deviation SMD of the surface roughness, the average deviation MMD of the friction coefficient, the MD bulk softness, and the compression characteristic value at a minute load were determined by the above-described measurement method, and are shown in Table 1.

[Comparative Example 3]
A resin to be an ethylene-containing ethylene-propylene random copolymer is supplied to an extruder, melted and kneaded, spun from a spinning nozzle hole, spun long fibers are deposited on the collecting surface, and a hot embossing roll is used. Then, embossing was carried out at an embossing rate of 18% (area of individual heat-sealed portions 0.3 mm ² ) to produce a spunbonded nonwoven fabric having a basis weight of 17 g / m ² . With respect to the produced spunbond nonwoven fabric, the average deviation SMD of the surface roughness, the average deviation MMD of the friction coefficient, the MD bulk softness, and the compression characteristic value at a minute load were determined by the above-described measurement method, and are shown in Table 1.

[Performance evaluation]
Regarding the nonwoven fabrics of Examples 1 to 4 and Comparative Examples 1 to 3, “feel” was measured and evaluated by the following method and shown in Table 1.

<Evaluation of touch>
Ten female monitors were evaluated for the touch of each nonwoven fabric in an environment of temperature: 25 ° C. and humidity: 40%. In accordance with the evaluation of each monitor, the following score was given, and the average score (rounded off the decimal point) of 10 monitors was used as the touch evaluation score.
5 points: Good touch.
4 points: The touch is slightly good.
3 points: Normal.
2 points: Slightly bad touch.
1 point: The touch is bad.

  As is clear from the results shown in Table 1, the spunbonded nonwoven fabrics of Examples 1 to 4 were sheets that had a better feel than the spunbonded nonwoven fabrics of Comparative Examples 1 to 3. Therefore, if the spunbonded nonwoven fabrics of Examples 1 to 4 are used for the outer layer sheet forming the outer surface of the disposable diaper, the touch is good, the improvement of the quality of the product can be expected, and the cost can be expected to be suppressed.

[Example 5]
Using the spunbond nonwoven fabric of Example 1 as an outer layer sheet, “Merry's Pants (registered trademark) smooth air through L size” manufactured by Kao Corporation, which is a diaper in the form shown in FIGS.

[Example 6]
A pants-type disposable diaper of Example 6 was manufactured in the same manner as in Example 1 except that the spunbonded nonwoven fabric of Example 4 was used for the outer layer sheet.

[Comparative Example 4]
A pants-type disposable diaper of Comparative Example 4 was produced in the same manner as in Example 1 except that the spunbond nonwoven fabric of Comparative Example 3 was used for the outer layer sheet.

[Comparative Example 5]
Goon (registered trademark) soft fit pants L size of Daio Paper Co., Ltd. was used as the pants-type disposable diaper of Comparative Example 5 as it was.

[Comparative Example 6]
Moonyman (registered trademark) Air Fit L size of Unicharm Corporation was used as the pants-type disposable diaper of Comparative Example 6 as it was.

[Comparative Example 7]
P & G Pampers (registered trademark) smooth pants L size was used as the pants-type disposable diaper of Comparative Example 7 as it was.

[Performance evaluation]
Example 5-6 relates pants type disposable diaper of Comparative Example 4-7, the above-mentioned measurement method, the mean deviation SMD 2 of the surface roughness of the collapsible portion of the outer _package, the compression ratio by KES compression testing machine of the stretchable portion , And the compression recovery rate of the expansion / contraction part by a KES compression tester was determined and shown in Table 2.
Moreover, regarding the pants-type disposable diapers of Examples 5 to 6 and Comparative Examples 4 to 7, “feel” was measured and evaluated by the following method and shown in Table 2.

<Evaluation of touch>
Ten female monitors were evaluated for the feel of each pant-type disposable diaper in an environment of temperature: 25 ° C. and humidity: 40%. In accordance with the evaluation of each monitor, the following score was given, and the average score (rounded off the decimal point) of 10 monitors was used as the touch evaluation score.
5 points: Good touch.
4 points: The touch is slightly good.
3 points: Normal.
2 points: Slightly bad touch.
1 point: The touch is bad.

  As is clear from the results shown in Table 2, the pants-type disposable diapers of Examples 5 to 6 were diapers having a good touch compared to the pants-type disposable diapers of Comparative Examples 4 to 7.

1 Disposable diapers (pants-type disposable diapers)
DESCRIPTION OF SYMBOLS 10 Absorbent main body 2 Top sheet 3 Back sheet 4 Absorber 5 Exterior body 5A Abdomen side exterior body 5B Back side exterior body 5C Inseam exterior body 51 Outer layer sheet 52 Inner layer sheet 53 Elastic member 54 Outer body fusion part 55 Outer fixing region 56 Main body side fixing region 57 ５８ 58 Hollow portion 6 Side cuff 61 Elastic member A for forming three-dimensional gather A ventral region, B dorsal region, C inseam region 100 Processing device 200 Partially stretched processing portion 21, 22 Convex and concave roll 210 Convex portion 220 Concave part 23 Steel matching embossing roller 300 Raised part 31 Convex roll 310 Convex part

Claims (12)

A disposable diaper comprising a top sheet, a back sheet, a vertically long absorbent main body provided with an absorbent body disposed between both sheets, and an exterior body disposed on the non-skin facing surface side of the absorbent main body. And
The exterior body has an outer layer sheet that forms an outer surface of the disposable diaper, and the outer layer sheet is made of a spunbond nonwoven fabric,
The spunbonded nonwoven fabric has a basis weight of 18 g / m ² or less, an average deviation SMD of the surface roughness of 3.20 μm or less, an average deviation MMD of the friction coefficient of 0.0085 or less, and an MD bulk softness. Disposable diaper whose is less than 5.0 cN.   The disposable diaper according to claim 1, wherein the spunbonded nonwoven fabric has a total area ratio (embossing rate) of a plurality of heat-sealing portions constituting the spunbonded nonwoven fabric occupying a surface area of one surface of 15% or less. The disposable diaper according to claim 1 or 2, wherein each of the plurality of heat-sealed portions constituting the spunbonded nonwoven fabric has an area of 0.3 mm ² or less.   The disposable diaper according to any one of claims 1 to 3, wherein the spunbonded nonwoven fabric is subjected to raising treatment.   The disposable diaper according to any one of claims 1 to 4, wherein the spunbond nonwoven fabric contains at least one of a surfactant and paraffin oil as a softening agent.   The disposable diaper according to any one of claims 1 to 5, wherein the spunbonded nonwoven fabric has a crimped long fiber content of 30% by mass or more and 100% by mass or less. The spunbonded nonwoven fabric, a disposable diaper according to any one of claims 1 to 6 compression property value at the time of small load is ^{15.0 (gf / cm 2) /} mm or less.   The disposable diaper according to any one of claims 1 to 7, wherein the spunbonded nonwoven fabric has a breaking strength in a direction perpendicular to the orientation direction of the constituent fibers of 7.0 N / 50 mm or more. The exterior body has an abdominal exterior body disposed on the wearer's abdomen and a back exterior body disposed on the back side,
The ventral exterior body and the back exterior body are each configured to include the outer layer sheet and an inner layer sheet that is disposed on the inner surface side of the outer layer sheet and forms the inner surface of the disposable diaper,
The ventral side exterior body and the back side exterior body each have a partial joining region in which the outer layer sheet and the inner layer sheet are partially joined outside the absorbent main body. The disposable diaper of any one of 1-5. The ventral exterior body and the back exterior body are each configured to include the outer layer sheet, the inner layer sheet, and a plurality of thread-like elastic members arranged between the sheets,
The partial joining region is formed by a plurality of exterior body fusion portions that are joined together by thermal fusion in the longitudinal direction and the lateral direction, the outer layer sheet and the inner layer sheet,
In the partial joining region, the plurality of elastic members are arranged in a laterally extended state so as not to pass through the plurality of exterior body fusion parts, and both ends of the elastic members arranged in the extended state are The outer layer sheet is fixed between the inner layer sheet and each of the outer layer sheet and the inner layer sheet forms a plurality of ridges extending continuously over the plurality of elastic members. Disposable diapers described in 1. The fiber orientation direction of the fibers constituting the outer layer sheet and the inner layer sheet is the same direction as the lateral direction of the disposable diaper,
The disposable diaper according to claim 7, wherein the outer package fusion part has a rectangular shape that is long in a direction orthogonal to the fiber orientation direction. A vertically long absorbent main body provided with a top sheet, a back sheet, and an absorbent body disposed between the two sheets, and an exterior body disposed on the non-skin facing surface side of the absorbent body, Are divided into an abdominal side portion arranged on the wearer's ventral side, a dorsal side portion arranged on the dorsal side, and a crotch portion located between them. A pants-type disposable diaper in which a pair of side seal parts is formed by joining both side edges of the side part,
The exterior body includes an outer layer sheet that forms an outer surface of the pants-type disposable diaper, and an inner layer sheet that is disposed on the inner surface side of the outer layer sheet, and has a stretchable portion that is stretchable in a lateral direction of the pants-type disposable diaper. With
The stretchable part of the exterior body has an average surface roughness average deviation SMD ₂ of 6.0 μm or less, a compression rate of 70% or more by the KES compression tester, and a compression recovery rate of 40% or less by the KES compression tester. A pants-type disposable diaper.

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