JP2019097972A - Disposable diaper - Google Patents

Abstract

To provide a disposable diaper excellent in even absorbency of an absorber and hardly generating breakage in the absorber.SOLUTION: An absorbency core 40 is formed with a plurality of non-accumulation parts 5,6 made of core formation materials, and a skin side core wrap sheet 41 and a non-skin side core warp sheet 42 are connected in each of the non-accumulation parts 5,6. The plurality of non-accumulation parts 5,6 include the central non-accumulation part 5 extending in a vertical direction X in a central part in a transverse direction Y of the absorbency core 40, and the plurality of pairs of line-symmetric non-accumulation parts 6 formed in line symmetry with the central non-accumulation part 5 as a symmetry axis. A length in the vertical direction X of the line-symmetric non-accumulation part 6 is 1/5 or less of a length in the vertical direction X of the central non-accumulation part 5. When setting regions I-V in a diaper 1 according to a prescribed method, the central non-accumulation part 5 and the line-symmetric non-accumulation parts 6 exist in the regions II and III, and the line-symmetric non-accumulation parts 6 do not exist in the region V.SELECTED DRAWING: Figure 3

Description

  The present invention relates to disposable diapers.

  Absorbent articles such as disposable diapers typically comprise a liquid permeable top sheet, a liquid impermeable back sheet and an absorbent disposed between the two sheets. In addition, the absorbent includes a liquid-retaining absorbent core in which a core-forming material containing wood pulp, a water-absorbent polymer, etc. is accumulated, and a water-permeable core wrap sheet for covering the absorbent core. It is known what is being done. The core wrap sheet plays the role of ensuring the shape retention of the absorber, preventing the core forming material from falling off, and the like.

  Conventionally, in disposable diapers, for the purpose of improving fit and liquid absorbability, a low basis weight portion having a basis weight lower than that of a through hole penetrating the absorbent core in the thickness direction or a peripheral portion in the absorbent core It is done to provide. For example, in Patent Document 1, in order to improve the fit and liquid absorbability of the disposable diaper, the absorbent core in the longitudinal direction (a direction corresponding to the front-rear direction of the wearer) does not substantially contain the absorbent material. It is described to extend to. Further, in Patent Document 2, in order to improve the leakage prevention property of urine and stool of the disposable diaper, a high basis weight portion in the central portion in the lateral direction (direction orthogonal to the longitudinal direction) in the crotch of the absorbent core Side portions in the lateral direction are low basis weight portions, and the high basis weight portions are provided with central bending induction portions consisting of slits, grooves or non-accumulated portions extending in the longitudinal direction, and the low basis weight portions are non-accumulated portions It has been described to provide a side fold induction consisting of

JP-A-2014-515981 JP, 2012-16435, A

  In the disposable diaper, when the absorber absorbs the excrement fluid such as urine and becomes wet, the absorber breaks down into multiple lumps due to a decrease in strength due to the fluid absorption and an increase in its own weight, etc. There is a problem that it is divided and, as a result, the liquid absorptivity of the diaper is significantly reduced. Moreover, in disposable diapers, the excretory fluid is uniformly absorbed in a wide range of the absorber, and "the ratio of the portion actually occupied for liquid absorption in the whole absorber" (absorber utilization rate) is high It is requested. It is difficult for the absorbent to absorb uniformly, and the absorbent utilization rate is low, so that the swollen part due to liquid absorption and the non-swelled part not absorbing liquid are notably mixed in the absorbent after liquid absorption. As a result, the steps are irregularly formed on the skin-facing surface of the absorbent after liquid absorption, and the skin-facing surface becomes irregular, which may cause inconveniences such as a reduction in the wearing feeling. There is not yet provided a disposable diaper which is resistant to breakage even after liquid absorption and which can uniformly absorb liquid in a wide range of the absorbent.

  Therefore, the subject of the present invention relates to providing a disposable diaper which is excellent in uniform absorbency of an absorber and in which breakage of the absorber does not easily occur.

  The present invention comprises a liquid-retaining absorber and a surface sheet disposed on the skin-facing side of the absorber, and is perpendicular to the longitudinal direction extending from the ventral side of the wearer to the dorsal side via the crotch A crotch which has a lateral direction and which is disposed to face the crotch at the time of wearing, a ventral side disposed on the ventral side of the wearer rather than the crotch, and a wearer more than the crotch A disposable diaper having a dorsal side disposed on the back side, wherein the absorbent body covers an absorbent core on which a core forming material including an absorbent material is accumulated, and a skin facing surface of the absorbent core. And the non-skin-side core wrap sheet covering the non-skin-facing surface of the absorbent core, wherein the diaper in the unfolded and stretched state is in the longitudinal direction Extends longitudinally from the ventral side to the dorsal side across the longitudinal center line bisected into two A plurality of non-accumulated portions of the core-forming material are formed in the absorbent core, and the skin-side core wrap sheet and the non-skin-side core wrap sheet are joined in each of the non-accumulation portions. The accumulation portion includes a central non-integral portion extending longitudinally in the lateral central portion of the absorbent core, and a plurality of pairs of line symmetrical non-integral portions formed in line symmetry with the central non-integral portion as an axis of symmetry. And the longitudinal length of the axisymmetric non-accumulating part is 1⁄5 or less of the longitudinal length of the central non-accumulating part, and the diaper according to <Method of Determining Region I to V> below. The present invention provides a disposable diaper in which the central non-accumulation portion and the line-symmetrical non-integration portion exist in the regions II and III and the line-symmetrical non-integration portion does not exist in the region V when the regions IV are set. is there.

<Method of Determining Regions I to V>
In the unfolded and stretched diaper, one imaginary straight line extending in the lateral direction through the longitudinal end on the ventral side of the absorbent body is used as a reference line, and the dorsal side of the reference line Draw five virtual straight lines parallel to the reference line at equal intervals. The distance between the imaginary straight lines is set to a value obtained by dividing the length in the longitudinal direction from the longitudinal center line to the longitudinal end on the ventral side of the absorber by 5 and further doubling it. Regions divided into five by these six virtual straight lines are referred to as region I, region II, region III, region IV, and region V in order from the one closest to the reference line.

  ADVANTAGE OF THE INVENTION According to this invention, the disposable diaper which is excellent in the uniform absorbency of an absorber, and which breakage of an absorber does not produce easily is provided.

FIG. 1 is a partial fracture of the surface sheet side showing an expanded state (expanded and expanded state) in which an elastic member of each part is expanded to expand an elastic member of each part of the embodiment of the disposable diaper of the present invention. It is a top view. FIG. 2 is a schematic cross-sectional view taken along line A-A of FIG. FIG. 3 is a schematic plan view of the skin facing surface side of the absorber in the diaper shown in FIG. FIG. 4 is a schematic cross-sectional view taken along line B-B of FIG. FIG. 5 is a view corresponding to FIG. 3 of another embodiment of the absorber according to the present invention. FIG. 6 is a schematic cross-sectional view of still another embodiment of the absorber according to the present invention.

  Hereinafter, the disposable diaper of the present invention will be described based on a preferred embodiment thereof with reference to the drawings. The disposable diaper 1 of this embodiment is shown by FIG.1 and FIG.2. The diaper 1 has a longitudinal direction X extending from the ventral side of the wearer to the dorsal side via the crotch and a transverse direction Y orthogonal thereto, and the crotch M and the crotch disposed at the crotch when worn A longitudinal side X includes an abdominal side F disposed on the ventral side of the wearer than the crotch M, and a dorsal side R disposed on the dorsal side of the wearer relative to the crotch M.

  The diaper 1 has a longitudinally long shape in the longitudinal direction X, the longitudinal direction coincides with the longitudinal direction X, and the width direction coincides with the transverse direction Y in plan view in the unfolded and extended state as shown in FIG. ing. In the diaper 1 as shown in FIG. 1, both side edges along the longitudinal direction X in the central portion in the longitudinal direction X including the crotch M are curved inward in an arc shape facing inward, and the center in the longitudinal direction X The part has an hourglass shape that is bound inwardly. The crotch M includes a not-shown excretory part opposing part (voiding point) which is disposed to face the excretory part such as the penis of the wearer when worn. The excretory part facing part is usually at a position slightly biased closer to the belly side F than the central part in the longitudinal direction X of the diaper 1.

  The diaper 1 is, as shown in FIGS. 1 and 2, a liquid-retaining absorber 4 and a liquid-pervious material which is disposed on the skin-facing side of the absorber 4 and which can come into contact with the skin of the wearer when worn. A surface sheet 2 and a liquid impermeable or water repellent back sheet 3 disposed on the non-skin facing side of the absorbent body 4 are provided. The absorber 4 is disposed between the two sheets 2 and 3. The absorbent body 4 has a longitudinally long shape in the longitudinal direction X in plan view as shown in FIG. 1, and a belly side across the longitudinal center line CLx that bisects the diaper 1 in the unfolded and stretched state in the longitudinal direction X It extends in the longitudinal direction X from F to the dorsal side R.

  In the present specification, the "skin-facing surface" is a surface of the absorbent article or a component thereof (for example, the absorber 4) that faces the skin of the wearer when the absorbent article is worn, ie, relatively worn. The “non-skin facing surface” is the side opposite to the skin side when wearing the absorbent article, ie, the side relatively away from the wearer's skin, when the absorbent article or the component thereof is worn. It is a face directed to (the clothing side worn by the wearer). Further, in the present specification, "at the time of wearing" means a state where a normal proper wearing position, that is, a correct wearing position of the absorbent article is maintained.

  The top sheet 2 and the back sheet 3 each have a size larger than that of the absorber 4 and extend outward from the periphery of the absorber 4. The back sheet 3 forms the outer shape of the diaper 1 in the unfolded and stretched state as shown in FIG. The top sheet 2 and the back sheet 3 extend outward from both side edges along the longitudinal direction X of the absorber 4 in the lateral direction Y, as shown in FIG. 2, and form side flaps with side sheets 34 described later doing. The side flap portion is a portion of the diaper 1 which is a member extending outward in the lateral direction Y from the absorbent body 4. As the top sheet 2 and the back sheet 3, various types of materials conventionally used in this type of absorbent article can be used without particular limitation. For example, various non-woven fabrics, apertured films and the like can be used as the top sheet 2, and resin films, laminates of resin films and non-woven fabrics, and the like can be used as the back sheet 3. The back sheet 3 includes, for example, a form of a liquid-impermeable film sheet alone and a form in which an exterior sheet is laminated on the non-skin facing surface of the film sheet, that is, the outer surface side. It is a non-woven fabric.

  A thread-like elastic member 31 is stretched along the transverse direction Y between the front sheet 2 and the back sheet 3 at the waist of each of the ventral side F and the dorsal side R, that is, the end in the longitudinal direction X The waist is fixed by the contraction of the elastic member 31 at the waist when the diaper 1 is worn. Moreover, the side sheet (seat for leak-barrier cuff formation) 34 is distribute | arranged to the left-right both sides in alignment with the vertical direction X in the surface sheet 2 side of the diapar 1, respectively. The side sheet 34 has an inner edge along the longitudinal direction X and an outer edge along the longitudinal direction X which is located outward in the lateral direction Y than the inner edge, and is a flat surface as shown in FIG. As viewed, the inner edge overlaps the absorber 4, and the outer edge extends outward from the side edge along the longitudinal direction X of the absorber 4 in the lateral direction Y and is joined to the back sheet 3. A thread-like elastic member 32 is fixed in a stretched state along the longitudinal direction X between the side sheet 34 and the back sheet 3 in the left and right leg portions arranged around the legs of the wearer, whereby When the diaper 1 is worn, the elastic members 32 contract to form a pair of leakproof cuffs on the leg portions. Further, at the inner edge of the side sheet 34, a thread-like elastic member 33 is fixed in an extended state along the longitudinal direction X, whereby at least the crotch M is reduced by the contraction of the elastic member 33 when the diaper 1 is worn. The leakproof cuff is formed on the The top sheet 2, the back sheet 3, the absorber 4, the elastic members 31, 32, 33 and the side sheet 34 are joined to each other by a known joining means such as a hot melt adhesive.

  The diaper 1 is a so-called spreadable disposable diaper, and as shown in FIG. 1, a pair of fastening tapes 35 is provided on both side edges (the side flaps) along the longitudinal direction X of the back side R of the diaper 1. , 35 are provided. A fastening portion (not shown) made of a male member of a mechanical surface fastener is attached to the fastening tape 35. Moreover, in the non-skin opposing surface of the belly side F of the diaper 1, the attachment area | region 36 which consists of a female member of a mechanical surface fastener is formed. The attachment region 36 is a non-skin facing surface of the back sheet 3 forming the non-skin facing surface of the belly side F, with a female member of a mechanical surface fastener by a known bonding means such as an adhesive or heat seal. It is formed by joining and fixing, and the fastening portion of the fastening tape 35 can be detachably fastened. When the diaper 1 is worn, the side flaps of the dorsal side R are extended to the ventral side of the wearer, and fastening tapes 35, 35 provided on the side flaps are attached to the outer surface of the abdominal side F Fasten to the attachment area 36.

  The skin opposing surface side of the absorber 4 is shown by FIG. The absorbent body 4 has a liquid-retaining absorbent core 40, a skin-side core wrap sheet 41 covering the skin-facing surface of the absorbent core 40, and non-skin covering the non-skin-facing surface of the absorbent core 40. A side core wrap sheet 42 is included. The absorbent core 40 and the core wrap sheets 41 and 42 are joined by a known joining means such as a hot melt adhesive. In the present embodiment, the absorbent core 40 has a single-layer structure, and in a plan view as shown in FIG.

  The absorbent core 40 is an accumulation of core-forming materials including an absorbent material. As the absorbent material, materials generally used as a material for forming this kind of absorbent core can be used without particular restriction, and for example, fiber materials such as wood pulp, synthetic fibers treated with a hydrophilizing agent (preferably And hydrophilic polymers). The absorbent core 40 may be a collection of fibrous materials, or a collection of particulate water-absorbing polymers supported on the collection.

  The skin side core wrap sheet 41 and the non-skin side core wrap sheet 42 may be 1) one continuous sheet or 2) separate sheets. As one example of the form of the above 1), one continuous core wrap sheet having a width twice to three times the length (width) of the absorbent core 40 in the transverse direction Y is the skin of the absorbent core 40 The entire area of the opposite surface is covered and extends outward from both side edges along the longitudinal direction X of the absorbent core 40 in the lateral direction Y, and the extension is rolled down below the absorbent core 40, The form which coat | covers the whole non-skin opposing surface of the absorptive core 40 is mentioned. And in this one core wrap sheet, the portion covering the skin facing surface of the absorbent core 40 is the skin side core wrap sheet 41, and the portion covering the non-skin facing surface of the absorbent core 40 is the non-skin side core wrap It is a sheet 42.

  In the case of 2), the length in the lateral direction Y, that is, the width may be the same or different between the skin side core wrap sheet 41 and the non-skin side core wrap sheet 42. If the two sheets 41 and 42 have different widths, either one may be longer. For example, the skin side core wrap sheet 41 has the same width as the maximum width of the skin facing surface of the absorbent core 40, that is, has a size capable of covering the entire skin facing surface of the absorbent core 40, The skin side core wrap sheet 42 can be wider than the sheet 41. The wide non-skin side core wrap sheet 42 covers the entire non-skin facing surface of the absorbent core 40 and extends outward in the width direction Y from both side edges along the longitudinal direction X of the absorbent core 40 The extended portion may be rolled up on the skin-side core wrap sheet 41 disposed opposite to the skin-facing surface of the absorbent core 40, and may cover both side edges along the longitudinal direction X of the sheet 41. .

  A liquid permeable sheet can be used as the core wrap sheets 41 and 42, and examples thereof include paper and non-woven fabric. However, from the viewpoint of reliably preventing the core wrap sheets 41 and 42 from being torn and reliably joining the two sheets 41 and 42 in the non-stacking portions 5 and 6 described later, non-woven fabrics are preferable as the two sheets 41 and 42. Non-woven fabrics have higher strength than paper and are less likely to be broken during processing, and when water-absorbing polymer particles are used as a core-forming material that constitutes an absorbent core, absorbency by swelling of water-absorbing polymer particles It can respond flexibly to core deformation. As the non-woven fabric, those manufactured by various manufacturing methods can be used without particular limitation. Moreover, as a nonwoven fabric, the hydrophilic nonwoven fabric which consists of a synthetic fiber to which the hydrophilization treatment was given is preferable.

The thickness of the absorbent core 40 (the thickness of portions other than the non-accumulated portions 5 and 6 described later) is preferably 1 mm or more, more preferably 2 mm or more, and preferably 10 mm or less, more preferably 6 mm or less.
The basis weight of the absorbent core 40 (the basis weight of portions other than the non-accumulated portions 5 and 6 described later) is preferably 50 g / m ² or more, more preferably 100 g / m ² or more, and preferably 400 g / m ² Or less, more preferably 300 g / m ² or less.
The basis weight (the basis weight of portions other than the non-accumulated portions 5 and 6 described later) of the core wrap sheets 41 and 42 is preferably 5 g / m ² or more, more preferably 7 g / m ² or more, and preferably 15 g / m ² It is m ² or less, more preferably 10 g / m ² or less.
The thickness of the structural member (absorbent core 40, surface sheet 2 etc.) of the diaper 1 or the diaper 1 is measured by the following method.

<Method of measuring thickness of disposable diaper or its component members>
Place the object to be measured in a horizontal place without wrinkles or bending, and measure the thickness of the object under a load of 5 cN / cm ² . Specifically, for measurement of thickness, for example, a thickness gauge PEACOCK DIAL UPRIGHT GAUGES R5-C (manufactured by OZAKI MFG. CO. LTD.) Is used. At this time, between the tip of the thickness meter and the object to be measured, the plate is circular or square in plan view, the size of which is adjusted so that the load on the object to be measured is 5 cN / cm ² Place an acrylic plate of about 5 mm and measure the thickness. The thickness is measured at 10 points, and their average value is calculated to be the thickness of the object to be measured.

  In the absorbent core 40, a plurality of non-integrated portions indicated by reference numerals 5 and 6 in the drawing are formed. The non-accumulated portions 5 and 6 constitute the absorbent core 40 and are portions where core-forming materials including absorbent materials such as a fiber material and a water-absorbing polymer are not accumulated. The basis weight of the forming material is substantially zero. The non-accumulated portions 5 and 6 can also be said to be through holes penetrating the absorbent core 40 in the thickness direction. The non-accumulation units 5 and 6 function as a fluid channel for excrement fluid such as urine, and have the function of diffusing the excrement fluid in the extension direction (longitudinal direction X in the present embodiment). Therefore, it is possible to absorb the excretory fluid uniformly to the whole absorbent core 40 depending on the arrangement of the non-accumulated portions 5 and 6. Incidentally, the above-mentioned "the basis weight is substantially zero" includes a mode in which a very small amount of the core forming material is present in the non-accumulated portions 5 and 6, for example, when the core forming material is unintentionally mixed. Ru. However, in such a mode, the amount of core forming material present in the non-accumulated portions 5 and 6 corresponds to “the skin-side core wrap sheet 41 in the non-accumulation portions 5 and 6 and the non-skin-side core wrap sheet 42 described later. "Conjugation" is not inhibited.

  The non-accumulated portions 5 and 6 (non-accumulated portions consisting of through holes) are portions formed by intentionally inhibiting the accumulation of core-forming materials in the step of accumulating core-forming materials at the time of manufacturing the absorbent core 40. is there. The absorbent core 40 having the non-accumulated portions 5 and 6 can be manufactured according to a conventionally known method for manufacturing an absorbent core. Specifically, for example, using a fiber stacking device, a core forming material (absorbent material) supplied on an air stream is sucked and deposited on a forming die formed on the outer peripheral surface of a rotating drum to be absorbed. In the method of obtaining the core 40, manufacturing may be performed using a mold having a predetermined pattern as the mold, for example, a mold in which the portions corresponding to the non-accumulated portions 5 and 6 protrude upward relative to the peripheral portion. it can. In the absorbent core 40 obtained by such a method, the parts where the core forming material is not present are the non-accumulated parts 5 and 6. In addition, as another manufacturing method of the absorptive core 40 which has the non-accumulation part 5 and 6, the absorptive core which does not have the non-accumulation part 5 and 6 is manufactured, and the punching process is carried out to the predetermined part of this absorptive core. It is also possible to adopt a method of forming the non-accumulated portions 5 and 6 by post-processing such as cutting and the like.

  As shown in FIG. 2, in the non-stacking portions 5 and 6, the skin-side core wrap sheet 41 and the non-skin-side core wrap sheet 42 are joined. With such a configuration, the adhesion between the absorbent core 40 and the both sheets 41 and 42 is improved, so that the shape retention property of the absorbent core 40 disposed between the both sheets 41 and 42 is improved, and the absorbent core is improved. Even if the absorbent material such as the water-absorbent polymer particles contained in the core-forming material constituting 40 swells by absorbing excrement fluid such as urine, the degree of deformation of the absorbent core 40 is suppressed. Further, combined with the fact that the skin side core wrap sheet 41 is joined to the surface sheet 2 by an adhesive and the non-skin side core wrap sheet 42 is joined to the back sheet 3 by an adhesive, this configuration Since the movement of the absorber 4 is restrained, the absorber 4 is difficult to move relative to the top sheet 2 and the back sheet 3 while the diaper 1 is worn. Therefore, the absorber 4 (absorbent core 40) is not easily broken during use of the diaper 1, and the excellent absorption performance can be stably exhibited. In addition, with such a configuration, the uptake of waste fluid by the absorbent core 40 is improved, and the embedding of the non-accumulated portions 5 and 6 due to the swelling of the absorbent material contained in the core-forming material is effectively prevented. Ru.

  The bonding method in particular of both sheets 41 and 42 in non accumulation part 5 and 6 is not restricted, for example, adhesives, such as a hot melt type adhesive agent, well-known bonding methods, such as fusion, can be used. The joint of the two sheets 41 and 42 in the non-stacking units 5 and 6 can be formed, for example, as follows. That is, an adhesive such as a hot melt adhesive is previously applied to the corresponding position of the non-accumulated portions 5 and 6 in at least one of the sheets 41 and 42, and the absorbent core 40 is covered with both sheets 41 and 42. After obtaining the absorber 4, pressing the non-accumulated portions 5, 6 of the absorber 4 from the skin facing surface and / or the non-skin facing surface side and pressing one or both of the two sheets 41, 42; Both sheets 41 and 42 can be joined in the non-stacking portions 5 and 6. The pressing process may employ known embossing such as embossing or ultrasonic embossing with or without heat. When the heating and pressing process, such as embossing with heat, is employed as the pressing process, the two sheets 41 and 42 are heated and pressure-bonded to each other. The two can join tightly.

  In particular, when the core wrap sheets 41 and 42 are non-woven fabrics composed of fibers containing polypropylene (PP) resin, in particular, non-woven fabrics composed only of PP, both sheets 41 in the non-accumulated portions 5 and 6 described above. , 42 can be performed only by pressing the sheets 41 and 42 without melting treatment of resin such as heating or ultrasonic waves, and without using an adhesive, and both sheets 41, 42 Sufficient bonding strength can be obtained at the 42 joints, which is advantageous in terms of processability, manufacturing cost, and the like.

  In the present embodiment, the joint portion between the two sheets 41 and 42 in the non-stacking portions 5 and 6 is located at the central portion in the thickness direction of the absorbent body 4 as shown in FIG. , 42 are recessed in the formation positions of the non-accumulated portions 5 and 6, respectively. Such a form of the joint of the two sheets 41 and 42 can be obtained by simultaneously pressing the two sheets 41 and 42 at the formation position of the non-stacked parts 5 and 6 in the method of forming the joint. The position of the junction of the two sheets 41 and 42 in the non-stacking portions 5 and 6 does not have to be at the central portion in the thickness direction of the absorber 4 and is unevenly distributed on the skin facing surface side, that is, the top sheet 2 side Alternatively, it may be unevenly distributed on the non-skin facing surface side, that is, on the back sheet 3 side. In the former case, the skin-side core wrap sheet 41 is flat, but the non-skin-side core wrap sheet 42 is recessed in the formation position of the non-accumulated portions 5 and 6. In the latter case, the non-skin side core wrap sheet 42 is flat, but the skin side core wrap sheet 41 is recessed in the formation position of the non-accumulated portions 5 and 6.

  In the non-accumulation sections 5 and 6, both sheets 41 and 42 may be joined at least at a part of each of the non-accumulation sections 5 and 6 and not across the entire area of the non-accumulation sections 5 and 6 However, from the viewpoint of stably achieving the function and effect by the non-accumulated portions 5 and 6, “the area of the joint of the two sheets 41 and 42 in the area of each of the non-accumulated portions 5 and 6 is The ratio “(joint portion occupancy rate)” is preferably as high as possible, and specifically preferably 70% or more, more preferably 80% or more, and ideally 100%. In the present embodiment, as shown in FIGS. 1 and 3, the non-stacking portions 5 and 6 have a long shape in one direction (longitudinal direction X) in plan view, specifically, a rectangular shape, The joint between the two sheets 41 and 42 is continuous over the entire length in the longitudinal direction X, ie, the longitudinal direction, of each of the rectangular non-stacking portions 5 and 6. Here, the “full length” means the full length in the longitudinal direction X of the non-accumulation portions 5 and 6 and the length corresponding thereto, and specifically means 90% or more of the total length of the non-accumulation portions 5 and 6 Do.

  The diaper 1 is characterized in terms of the arrangement pattern of the plurality of non-accumulated portions 5 and 6 in the absorbent core 40. That is, as shown in FIG. 3, the plurality of non-stacked portions 5 and 6 have a central non-stacked portion 5 extending in the longitudinal direction X at the central portion in the transverse direction Y of the absorbent core 40 and the central non-stacked portion And a plurality of pairs of axisymmetric non-integrated portions 6 formed axisymmetrically with 5 as an axis of symmetry. The length in the vertical direction X of the line symmetrical non-stacking portion 6 is equal to or less than 1⁄5 of the length in the vertical direction X of the central non-stacking portion 5. And when area | region IV is set to the diapar 1 according to the following <determination method of area | region IV>, the center non-accumulation part 5 and the line-symmetrical non-integration part 6 exist in the area | regions II and III, the area | region V There is no line symmetry non-integration unit 6 in

<Method of Determining Regions I to V>
In the unfolded and stretched diaper 1 (see FIG. 1), as shown in FIG. 3, a virtual line extending in the transverse direction Y through the longitudinal end (front end) 4F on the ventral side F side of the absorber 4 A straight line is taken as a reference line V1, and five virtual straight lines V2 to V6 parallel to the reference line V1 are drawn at equal intervals Sx on the back side R side of the reference line V1. The interval Sx between the virtual straight lines V1 to V6 is defined by dividing the longitudinal length Lx from the longitudinal center line CLx for bisecting the unfolded and stretched diaper 1 in the longitudinal direction X to the front end 4F of the absorber 4 by 5. And then double the value. Regions divided into five by the six imaginary straight lines V1 to V6 are referred to as a region I, a region II, a region III, a region IV, and a region V in order from the one closer to the reference line V1.

  The regions I to V determined by the above determination method are mainly used to specify the positions of the non-accumulated portions 5 and 6 in the absorber 4 (the absorbent core 40). It is also considered appropriate to set the imaginary straight lines V1 to V6 to be divided based on the dimension (length in the longitudinal direction X) of the absorber 4. However, in the present invention, as described above, the diaper 1 is bisected in the longitudinal direction X based on the length in the longitudinal direction X in the diaper 1 in the unfolded and stretched state as shown in FIG. The virtual straight lines V1 to V6 are set based on the vertical center line CLx. The reason is that the positions of the non-accumulated parts 5 and 6 should be determined based on the absorption site of excretory fluid such as urine in the absorber 4 when the diaper 1 is worn, and such an absorption site is It is because it can not be specified only by the size of absorber 4, and it is necessary to consider the position etc. of absorber 4 in diaper 1. Assuming that the absorber is always disposed at the longitudinal center of the unfolded and stretched diaper, setting the imaginary straight lines V1 to V6 on the basis of the longitudinal length of the absorber is generally acceptable. Although it thinks, the arrangement | positioning position of the absorber in a diaper is various, For example, in the diaper 1, the absorber 4 may be unevenly distributed in the belly side F side of the diaper 1. FIG. In that case, since the center of the longitudinal direction X of the absorber 4 does not coincide with that of the unfolded and stretched diaper 1, the regions I to V are determined based on the length of the longitudinal direction X of the absorber 4 Also, each of the regions thus determined may not reflect the site where the waste fluid is actually absorbed in the absorber 4, and as a result, the non-accumulated portions 5, 6 are formed at appropriate positions. May be difficult to do. Therefore, in the present invention, virtual straight lines V1 to V6 are set based on the longitudinal length of the disposable diaper in the unfolded and stretched state, and the regions I to V are determined.

  In the above determination method, the “longitudinal end (front end) 4F of the absorber 4” through which the reference line V1 passes is the one of the constituent members of the absorber 4 closest to the waist end 1F on the ventral side F side of the diaper 1 It is a longitudinal end. Therefore, for example, in the case where the core wrap sheets 41 and 42 extend from the longitudinal end (front end) on the abdominal side F side of the absorbent core 40 to the waist end 1F side, the absorbency of both sheets 41 and 42 The front end of the extension from the front end of the core 40 is the front end 4F of the absorber 4. In the present embodiment, all the components of the absorbent body 4, that is, the lengths of the absorbent core 40 and the skin side core wrap sheet 41 and the non-skin side core wrap sheet 42 in the longitudinal direction X are identical to each other. The front end 4F of the body 4 coincides with the longitudinal end (front end) of the belly side F of each of the three components.

  Further, in the present embodiment, as shown in FIG. 3, the length in the longitudinal direction X of the absorber 4 is the same as the length in the longitudinal direction X of the regions IV, and the absorber 4 is a region I in the longitudinal direction X It is divided into five equal parts. However, the absorber 4 is not limited to this, and the present invention includes a form in which the length in the longitudinal direction X of the absorber 4 is different from the length in the longitudinal direction X of the regions IV. Specifically, 1) the length of the longitudinal direction X of the absorber 4 is shorter than the length of the longitudinal direction X of the regions IV, that is, the longitudinal direction end of the back side R of the absorber 4 (rear End) 4R is positioned closer to the front end 4F of the absorber 4 than the virtual straight line V6, and 2) the length of the absorber 4 in the longitudinal direction X is longer than the length of the region IV in the longitudinal direction X That is, the rear end 4R of the absorber 4 may be located farther from the front end 4F of the absorber 4 than the virtual straight line V6. In a typical example of the absorbent body 4 (absorbent core 40) according to the above 1), the rear end 4R of the absorbent body 4 is located between the imaginary straight lines V5 and V6 or between the imaginary straight lines V4 and V5. Do.

  Further, in the present embodiment, as shown in FIG. 3, one absorbent absorbent 4 (the diaper 1 in the unfolded and stretched state) is bisected in the horizontal direction Y and one on the horizontal center line CLy extending in the vertical direction X The central non-integrated portion 5 continuously extends in the longitudinal direction X, and three pairs (six) of line-symmetrical non-integrated portions 6 are formed on both sides in the lateral direction Y of the central non-integrated portion 5 . The non-stacking portions 5 and 6 have a rectangular shape in a plan view of the absorber 4 as shown in FIG. 3, and the longitudinal direction thereof coincides with the longitudinal direction X. The three pairs of line symmetrical non-integration units 6 are intermittently arranged at equal intervals in the longitudinal direction X. Moreover, the separation distance from the central non-integration part 5 of each of the plurality (six) of line symmetry non-integration parts 6 is the same as each other, and therefore, it is located on one side in the lateral direction Y with respect to the central non-integration part 5 A plurality of (three) axisymmetric non-integrated portions 6 are mutually at the same position in the lateral direction Y, and a plurality of (three) axisymmetric non-integrated portions 6 located on the other side are mutually co-located in the lateral direction Y It is in. The plurality of line-symmetrical non-integrated portions 6 have the same shape and the same size in plan view.

  In the diaper 1, the regions II and III are regions where the excretory part facing portion (voiding point), which is a portion that first receives excretory fluid such as urine excreted by the wearer, is absorbed because the excretory fluid is concentrated The body utilization rate is particularly high. The presence of the central non-accumulating portion 5 and the line-symmetrical non-accumulating portion 6 functioning as a fluid channel for excretory fluid such as urine in the absorbent body 4 in the regions II and III makes the excrement fluid non-accumulating portion 5 , 6 to diffuse in their extending directions, and uniform absorption of the absorber 4 is achieved. In particular, the central non-accumulating portion 5 having a relatively long length in the longitudinal direction X plays a main role as a liquid passage.

  In addition, the central part of absorber 4 in the horizontal direction Y in regions II and III is a place where excretory fluid particularly concentrates, so after absorption of liquid, expansion tends to be larger than that in the peripheral part, The occurrence of partial swelling in the absorbent body 4 may give the viewer an impression that uniform absorption has not been performed, which may lead to a decrease in the reliability of the disposable diaper product. On the other hand, in the diaper 1, the central non-stacked portion 5 where the core forming material is not present at the central portion of the absorber 4 in the lateral direction Y in the regions II and III, which is a portion where swelling by liquid absorption tends to be large. Is formed, and the liquid can be moved in the longitudinal direction X (front-rear direction), so that such a problem hardly occurs.

  In addition, when the diaper 1 is worn, the absorbent body 4 is usually sandwiched between the thighs of the wearer in the areas II and III, so that the absorbents 4 are mainly absorbed in the areas II and III. The sex core 40 is fragile due to the external force caused by the movement of the wearer. In particular, in the case where the absorbent core 40 absorbs the excretory fluid to be in a wet state, and the strength decreases and the weight is increased as compared with the dry state, the absorbent core 40 is in a more fragile state and receives external force. And there is concern that it will be divided into multiple chunks. On the other hand, in the diaper 1, the skin-side core wrap sheet 41 and the non-skin-side core wrap sheet 42 are joined in all of the plurality of non-accumulated portions 5 and 6 present in the regions II and III. Since the absorbent core 40 is firmly restrained by the both sheets 41 and 42 at a plurality of locations in the regions II and III, breakage of the absorbent core 40 does not easily occur even in a wet state. In particular, the line symmetric non-integrated portion 6 having a relatively short length in the longitudinal direction X plays a dominant role in preventing the breakage of the absorbent core 40, and this line symmetric non-integrated portion 6 has a central non-integrated portion. Since a plurality of pairs are formed in line symmetry with the accumulation portion 5 as the axis of symmetry, breakage of the absorbent core 40 is effectively prevented.

  On the other hand, the region V is the region farthest from the regions II and III in which the excretory part facing portion is present, and is a portion where the absorber utilization factor is low. There is little need to diffuse waste fluid to such a region V, but rather, if the region V is provided with the line symmetrical non-integrated portion 6 where no core forming material exists, the line symmetrical non-integrated portion before the diaper 1 is used. The user recognizes the difference in level of the absorber 4 due to the absence of the core forming material at the formation position of 6, and thereby the user can not absorb uniformly, unnecessary anxiety such as the absorber being divided, etc. There is a risk of giving it. Therefore, as shown in FIG. 3, the line-symmetrical non-integrated portion 6 does not exist in the region V. In the present embodiment, the line symmetry non-integration unit 6 is not present in the region IV. From the same point of view, in the present embodiment, the central non-integrated portion 5 is not present in the region V. It is important to arrange the central non-integral portion 5 and the line-symmetrical non-integral portion 6 only at the minimum necessary portions from the viewpoint of uniform absorption, breakage prevention of the absorber, and the like.

  In the present embodiment, as shown in FIG. 3, the central non-integrated portion 5 is present not only in the regions II and III but also in the regions I and IV, more specifically, the regions I to IV It extends continuously over the According to such a configuration, since the excretory fluid is efficiently diffused to the regions I to IV by the central non-accumulation part 5, the uniform absorptivity of the absorber 4 is improved, and the improvement of the absorber utilization rate can be expected. Further, in the present embodiment, the central non-accumulation portion 5 is present in the regions I to IV where the probability of the presence of urine is relatively high, and the skin side core wrap sheet 41 and the non-skin side core in the central non-accumulation portion 5 Since the wrap sheet 42 is joined, the absorbent core 40 is unlikely to be broken even in a wet state.

  Further, in the present embodiment, as shown in FIG. 3, not only the central non-integrated portion 5 but also the line symmetric non-integrated portion 6 extends in the longitudinal direction X. Thus, since all of the plurality of non-accumulated portions 5 and 6 present in the regions II and III extend in the longitudinal direction X, the excrement fluid concentrated on the regions II and III including the excretory part facing portion Can be more efficiently diffused in the longitudinal direction X, and the uniform absorption of the absorber 4 and the utilization of the absorber can be further improved. Further, in the present embodiment, the skin-side core wrap sheet 41 and the non-skin-side core wrap sheet 42 are also bonded to each other in the line symmetric non-accumulation portion 6, so that the absorbent core 40 is broken even in a wet state. It is hard to occur.

  Further, in the present embodiment, as shown in FIG. 3, both of the non-stacking portions 5 and 6 continuously extend in the longitudinal direction X. The term "continuously extending" as used herein means not only the form in which the non-stacking portions are continuous without interruption in the vertical direction but also the small non-stacking portions having a relatively short longitudinal length, as shown in the figure. (A) preferably includes a plurality of intermittent arrangements with a slight gap (preferably 5 mm or less). The latter form, that is, the non-integrated portion consisting of a collection of small non-integrated portions, is strictly discontinuous in the longitudinal direction, but the distance between the small non-integrated portions is narrow and substantially continuous in the longitudinal direction. Therefore, it can function as a drainage channel for excretory fluid.

  As described above, although the non-accumulated portions 5 and 6 are useful for uniform absorption and prevention of breakage of the absorbent body 4, they are, for example, absorbed before using the diaper 1 because they are portions where the core forming material is not present. When the body 4 is visually observed from the outside, the absorber 4 is felt to be divided at the formation position of the non-accumulated portions 5 and 6, and depending on the observer, the absorber 4 such as liquid absorbability is mainly used. There may be doubts about the performance played on the Therefore, it is desirable that the non-accumulation units 5 and 6 be as unobtrusive as possible within the range in which the above-described effects can be obtained. From such a point of view, the length (width) of the non-stacked portions 5 and 6 in the lateral direction Y is preferably 5 mm or less. The width of the non-accumulated portions 5 and 6 is preferably 1 mm or more, and more preferably from the viewpoint of the balance between the expression of predetermined effects and effects of the non-accumulated portions 5 and 6 and the inconspicuousness of the non-accumulated portions 5 and 6 Is 2 mm or more, and preferably 5 mm or less, more preferably 4 mm or less. The widths of the non-stacked portions 5 and 6 may be the same as or different from each other. Here, the “width” (the length in the horizontal direction Y) of the non-stacked portions 5 and 6 means the maximum width when the width is not constant in the vertical direction X. Similarly, the width of the non-accumulated portions 5 and 6 means the maximum width when the widths are different between the skin facing surface and the non-skin facing surface of the absorber 4.

  The plan view shape of the central non-accumulating portion 5 is not limited to the rectangular shape as shown in FIG. 3 as long as it has a long shape in the longitudinal direction X, for example, an oval, a rhombus, or a polygonal shape of five or more Good. The length of the central non-accumulation portion 5 in the longitudinal direction X is the longitudinal direction of the absorbent core 40 from the viewpoint of the balance between the expression of the predetermined effect and effect by the non-accumulation portion 5 and making the non-accumulation portion 5 inconspicuous. Preferably, it is 40% or more, more preferably 50% or more, and preferably 80% or less, more preferably 70% or less, with respect to the length of X. Further, from the viewpoint of leakage prevention, it is preferable that the longitudinal end of the central non-integrated portion 5 does not reach the longitudinal end of the absorbent core 40 as shown in FIG. Preferably, the directional end is not an open end, but a closed end as shown in FIG.

  FIG. 4 shows a central non-accumulating portion 5 of the absorbent body 4 shown in FIG. 3 and a cross section along the lateral direction Y in the vicinity thereof. In the present embodiment, as shown in FIG. 4, the absorber 4 is provided on both sides in the lateral direction Y of the central non-accumulation portion 5 (junction of core wrap sheets 41 and 42) from the central non-accumulation portion 5 in the lateral direction. A gradation region 4G is provided in which the basis weight of the absorber 4 (the absorbent core 40) gradually increases in the outward direction of Y (away from the central non-accumulated portion 5). The gradation region 4G is adjacent to the central non-accumulation portion 5 and exists along the entire length of the side edge along the longitudinal direction X of the central non-accumulation portion 5. Further, the gradation region 4G does not reach both ends in the horizontal direction Y (both side edges along the longitudinal direction X) of the absorber 4, and between the central non-accumulated portion 5 and the region where the basis weight in the absorber 4 is constant. In between. When the absorber 4 has such a gradation area 4G, an effect can be expected that the presence of the central non-accumulated portion 5 becomes less noticeable.

  The length (width) 4GW (see FIG. 4) of the gradation region 4G in the horizontal direction Y is the length of the central non-integrated portion 5 in the horizontal direction Y from the viewpoint of more reliably achieving the effects of the gradation region 4G. The width is preferably longer than 5 W (see FIG. 4), and in particular, the magnitude 4 GW is larger than the value obtained by doubling the width 5 W, that is, the magnitude relationship of “4 GW> 5 W × 2” is established. It is preferable to do. The ratio of both is preferably 2 or more, more preferably 5 or more, and preferably 30 or less, more preferably 20 or less, as 4 GW wide / 5 W wide, on the assumption that the width is 4 GW> the width 5 W.

  The plan view shape of the line-symmetrical non-stacking portion 6 is not limited to the rectangular shape as shown in FIG. 3 and may be, for example, a circle, an ellipse, a parallelogram, a rhombus, a polygon shape of five or more. Further, from the viewpoint of preventing breakage of the absorber 4, the plan-viewed shape of the line symmetrical non-integrated portion 6 is a vertically long shape as shown in FIG. 3, that is, a shape in which the length in the longitudinal direction X is longer than the length in the transverse direction Y Is preferred. For example, when the planar view shape of the absorber 4 is an ellipse or a rhombus, it is preferable that the major axis direction of the ellipse or the rhombus coincides with the longitudinal direction X.

  As described above, the length in the longitudinal direction X of the line-symmetrical non-integrated portion 6 is 1⁄5 or less of the length in the longitudinal direction X of the central non-integrated portion 5, preferably 1⁄6 or less, more preferably It is 1/8 or less. Since the main role of the line symmetrical non-accumulating part 6 is to prevent the absorber 4 from breaking, the main role is to improve the diffusion of the excrement fluid in the longitudinal direction X, and thus to improve the uniform absorption of the absorber 4. The length in the longitudinal direction X may be thus shorter than that of the central non-stacking portion 5.

  In addition, the length of the axisymmetric non-accumulating portion 6 in the longitudinal direction is a balance between the expression of predetermined effects and effects of the non-accumulating portion 6 and making the non-accumulating portion 6 inconspicuous. The length is preferably 3% or more, more preferably 4% or more, and preferably 40% or less, more preferably 20% or less, and more preferably 10% or less, with respect to the length in the longitudinal direction X of

  Since regions II and III are regions in which breakage of absorber 4 is particularly likely to occur, in regions II and III, a large number of line symmetrical non-integrated portions 6 useful for preventing breakage of absorbent core 40 may be present preferable. From such a viewpoint, it is preferable that the total number of pairs of line symmetrical non-integrated portions 6 present in regions II and III is larger than the total number of pairs of line symmetric non-integrated portions 6 present in regions I and IV. In the present embodiment, as shown in FIG. 3, the line-symmetrical non-consolidated portion 6 is not present in the regions I and IV, which is such a preferable form. The total number of pairs of axisymmetric deconcentrated portions 6 present in the regions II and III is preferably 2 in view of the balance between prevention of breakage of the absorber 4 and making the presence of the axisymmetric deconsolidated portions 6 inconspicuous. The number of pairs is more preferably 3 pairs or more, and preferably 6 pairs or less, more preferably 5 pairs or less.

  From the same point of view, it is preferable that the total area S1 of the line-symmetrical non-integrated portions 6 present in the regions II and III be larger than the total area S2 of the line-symmetrical non-integrated portions 6 present in the regions I and IV. The total areas S1 and S2 mean the sum of the areas of the line-symmetrical non-accumulated portions 6 on the skin-facing surface of the absorbent body 4 (the skin-facing surface of the skin-side core wrap sheet 41).

Further, from the viewpoint of making the non-stacked parts 5, 6 as inconspicuous as possible, the surface sheet 2 located in the region where the non-stacked parts 5, 6 are present is a non-stacked part A high basis weight and a thick one are preferable so as to be able to fill in the corresponding depressions and to visually hide the non-accumulated portions 5 and 6. Specifically, the surface sheet 2 located in the region where the non-accumulated portions 5 and 6 are present preferably has a basis weight of 30 g / m ² or more, more preferably 32 g / m ² or more, and a thickness of preferably 1 mm. The above, more preferably 1.5 mm or more. In the present embodiment, since the non-accumulated portions 5 and 6 are present in the regions I to IV as shown in FIG. 3, the surface sheet 2 has such a high basis weight and thickness in at least the regions I to IV. It is preferable that the entire top sheet 2 including the region V may have such high basis weight and thickness. With regard to the upper limit of the basis weight and thickness of the surface sheet 2 located in the region where the non-accumulated portions 5 and 6 are present, the basis weight is preferably from the viewpoint of giving practically sufficient strength to the surface sheet 2 The thickness is preferably 50 g / m ² or less, more preferably 45 g / m ² or less, and the thickness is preferably 8 mm or less, more preferably 6 mm or less. In addition, the top sheet 2 may be a single sheet, or may be a laminated structure of a plurality of sheets formed by stacking a plurality of sheets. From the viewpoint of making the non-accumulated portions 5 and 6 inconspicuous and the viewpoint of cost, the surface sheet 2 has a laminated structure of two sheets, and has a three-dimensional uneven structure on at least one surface (skin facing surface) A non-woven fabric having is preferred.

  Hereinafter, other embodiments of the present invention will be described with reference to the drawings. About the other embodiment mentioned below, a component different from diaper 1 (absorber 4) mentioned above is mainly explained, the same component attaches the same numerals, and omits explanation. The description about the diaper 1 (absorbent body 4) is applied as appropriate to components that are not particularly described.

  In the absorbent body 4A shown in FIG. 5, the position closer to the front end 4F (front end of the absorbent core 40) of the absorber 4A than the longitudinal end (front end) 5F of the ventral side F side of the central non-accumulated part 5 An axisymmetric non-integration unit 6 is present. More specifically, as shown in FIG. 5, in the absorber 4A, not only the regions II and III but also the region I is formed with a pair (two) of line symmetrical non-integrated portions 6, and this region I The pair of axisymmetric non-integrated portions 6 are located closer to the front end 4F of the absorber 4A than the front end 5F of the central non-integrated portion 5. In the region I, the central non-accumulation portion 5 extends from the region II, and the excretory fluid such as urine present in the region II is transferred to the region I by the central non-accumulation portion 5 and the longitudinal direction X in the region I In the absorbent body 4 (absorbent core 40), the region located in the longitudinal direction X outside the front end 5F of the central non-accumulated portion 5 absorbs the waste fluid and becomes wet. There is concern that it will break. However, in the absorber 4A, as described above, the line symmetrical non-integrating part 6 is present outward in the longitudinal direction X from the front end 5 F of the central non-integrating part 5. Such concern is eliminated because the wrap sheet 41 and the non-skin side core wrap sheet 42 are joined.

  In the absorber 4B shown in FIG. 6, the length (width) of the non-accumulated portions 5 and 6 in the lateral direction Y gradually increases from the skin facing surface 43 to the non-skin facing surface 44 of the absorber 4B. . In other words, the length (width) of the non-accumulated portions 5 and 6 in the lateral direction Y gradually decreases from the non-skin facing surface 44 of the absorber 4 B toward the skin facing surface 43. Therefore, in the absorbent body 4B, the width is different between the skin facing surface 43 and the non-skin facing surface 44 in each of the non-accumulation portions 5 and 6, and “the width Wa at the skin facing surface 43 <the non-skin facing surface 44 The magnitude relationship of “width Wb” of is established. The width Wa of the central non-integrated portion 5 and the width Wa of the line-symmetrical non-integrated portion 6 may be the same as or different from each other, and the width Wb of the central non-integrated portion 5 and the line-symmetrical non-integrated portion 6 The widths Wb may be the same as or different from each other.

  In the absorbent body 4B in which the above-described magnitude relationship holds with respect to the length (width) of the non-accumulated portions 5 and 6 in the lateral direction Y, the width of the absorbent core 40 is constant in the thickness direction as shown in FIG. And a tapered portion 40B whose width gradually decreases from the skin facing surface 43 toward the non-skin facing surface 44, and the tapered portion 40B in the non-accumulation portions 5, 6 and the lateral direction Y has It is adjacent.

  Generally, the skin facing surface 43 of the absorber 4B is a surface that is easily observed outside compared to the non-skin facing surface 44, but if the width Wa of the non-accumulation portions 5, 6 at the skin facing surface 43 is too large. , And a person who observes the skin facing surface of the unused diaper strongly impresses that the absorber 4B is divided at the formation position of the non-accumulated portions 5 and 6, whereby the observer absorbs the liquid And the like, the performance mainly exhibited by the absorbent body 4B is questioned, which may lead to a decrease in the reliability of the diaper. On the other hand, if the width Wa of the non-accumulated portions 5, 6 is made too small in fear of this, the bonding strength between the core wrap sheets 41, 42 in the non-accumulated portions 5, 6 is reduced, thereby absorbing particularly in the wet state. The shape retention of the sex core 40 may be reduced, and the above-described effects of the non-accumulated portions 5 and 6 may not be sufficiently exerted. On the other hand, in the absorber 4B, the magnitude relationship of “width Wa at the skin facing surface 43 <width Wb at the non-skin facing surface 44” is established in the non-stacking portions 5 and 6 as described above. Therefore, although the presence of the non-accumulated portions 5, 6 is not noticeable when the skin-facing surface (the surface sheet 2 side) of the diaper 1 is observed, both the sheets 41, 42 are strong in the non-accumulated portions 5, 6 And the predetermined effect by the non-accumulated portions 5 and 6 is stably exerted.

  Further, in the non-accumulation portions 5 and 6, when the magnitude relation of “width Wa on the skin facing surface 43 <width Wb on the non-skin opposing surface 44” is satisfied, the skin side core wrap sheet 41 in the non accumulation portions 5 and 6 In the cross-sectional view along the transverse direction Y as shown in FIG. 6, the thickness of the joint between the sheet and the non-skin-side core wrap sheet 42 is outward in the transverse direction Y from the central portion in the transverse direction Y Will gradually increase toward the The joint portion between the two sheets 41 and 42 in the non-accumulation portions 5 and 6 has such a structure (arch structure) in which the central portion in the lateral direction Y has a relatively small thickness and both side portions have a relatively large thickness. When it has, since the resistance with respect to the external force of this junction part itself improves, it leads to the improvement of shape retention property of absorptive core 40.

  From the viewpoint of more reliably achieving the function and effect of the joint portion of the arch structure of both sheets 41 and 42, the thickness of the joint portion at the center in the lateral direction Y of the non-accumulation portions 5 and 6 is T1. When it is assumed that the thickness of the bonding portion at the end portion in the lateral direction Y of the non-stacked portions 5 and 6 is T2, it is preferable that thickness T1 <thickness T2.

  When the absorbent core 40 contains a fiber material such as wood pulp and a water absorbent polymer (water absorbent polymer particles) as a core forming material (absorbent material), a fiber material for the water absorbent polymer in the tapered portion 40B The mass ratio of (weight of fiber material / mass of water absorbing polymer) is preferably lower than that in the constant width portion 40A. That is, it is preferable that the tapered portion 40B has a smaller content of the water absorbing polymer than the constant width portion 40A. When a large amount of a water-absorbent polymer whose swelling degree due to liquid absorption is larger than that of the fiber material is contained in a large amount in the taper portion 40B adjacent to the non-accumulation portions 5 and 6 in the lateral direction Y It is feared that the portion 40B swells significantly, and thereby the width and shape of the non-accumulated portions 5, 6 change significantly, and the onset of a predetermined effect by the non-accumulated portions 5, 6 is inhibited. As described above, with regard to the mass ratio of the fiber material to the water-absorbent polymer, by establishing the magnitude relationship of “tapered portion 40 B <constant width portion 40 A”, swelling of the tapered portion 40 B after liquid absorption is suppressed. Such concerns are wiped out.

  The absorbent core 40 having the constant width portion 40A and the tapered portion 40B can be manufactured according to a conventionally known method for manufacturing an absorbent core using a fiber stacking device. Specifically, for example, using a stacking device, the fibrous material and the water-absorbing polymer particles supplied in an air stream are sucked and deposited on a forming die formed on the outer peripheral surface of a rotating drum to be an absorbent core. In the method for obtaining 40, as the mold, a shape in which a portion corresponding to the non-accumulated portions 5 and 6 protrudes upward relative to the peripheral portion, and the portion gradually decreases in width toward the upper portion (a tapered portion 40B can be manufactured by using a mold having a reverse taper shape in which the decreasing direction of the width is reverse. In addition, since the water-absorbing polymer particles contained in the tapered portion 40B are more likely to fall off than the constant-width portion 40A, the “(water-absorption in the constant-width portion 40A described above” can be obtained during the production of the absorbent core 40 Water absorption as usual, even without special measures to establish the magnitude relationship of “the mass ratio of the fiber material to the polymer)> (the mass ratio of the fiber material to the water absorbing polymer in the tapered portion 40B)” If an absorbent core 40 in which the polymer particles are uniformly distributed throughout is manufactured, many water-absorbent polymer particles fall off from the tapered portion 40B during the period from its manufacture to its use, so the use of the absorbent core 40 When the diaper 1 is worn, that is, the magnitude relationship holds.

  The gradation region 4G (see FIG. 4) of the absorber 4 described above is formed by compressing the absorbent core 40 having the tapered portion 40B in the thickness direction of the absorbent core 40. The absorbent core 40 having the gradation region 4G formed in this manner does not have the tapered portion 40B because the tapered portion 40B is deformed by such compression and the tapered shape is broken.

  As mentioned above, although this invention was demonstrated, this invention is not restrict | limited to embodiment mentioned above, It can change suitably. The disposable diaper of the present invention is not limited to the unfolded disposable diaper as in the above embodiment, but can be applied to all diapers used for absorbing body fluid, and can be applied to, for example, pants-type disposable diapers . A pants-type disposable diaper typically has a liquid-retaining absorbent, a surface sheet disposed on the skin-facing surface of the absorbent, and an exterior disposed on the non-skin-facing surface of the absorbent. A structure in which a pair of side seal portions, a waist opening portion and a pair of leg opening portions are formed by joining both side edges of the ventral side and the back side along the longitudinal direction of the outer package Have. Further, the following appendices will be disclosed regarding the embodiment of the present invention described above.

<1> A liquid-retaining absorbent body and a surface sheet disposed on the skin-facing surface side of the absorbent body, and a longitudinal direction extending from the ventral side of the wearer to the dorsal side via the crotch and a transverse direction orthogonal thereto And a crotch portion disposed opposite to the crotch portion when worn, a ventral side disposed on the ventral side of the wearer relative to the crotch portion, and a back of the wearer relative to the crotch portion A disposable diaper having a dorsal side disposed on the side, wherein
The absorbent body includes an absorbent core in which a core-forming material containing an absorbent material is accumulated, a non-woven skin side core wrap sheet covering the skin facing surface of the absorbent core, and a non-skin of the absorbent core. From the belly side to the back side across the longitudinal center line which is configured to include the non-skin side core wrap sheet made of non-woven fabric covering the opposite surface and which bisects the diaper in the unfolded and stretched state in the longitudinal direction Extends longitudinally across the
A plurality of non-accumulated portions of the core-forming material are formed in the absorbent core, and the skin-side core wrap sheet and the non-skin-side core wrap sheet are joined in each of the non-accumulation portions.
The plurality of non-integrated portions are a central non-integrated portion extending longitudinally in the lateral central portion of the absorbent core and a plurality of pairs of lines formed in line symmetry with the central non-integrated portion as an axis of symmetry. A longitudinal length of the axisymmetric non-integrated portion is 1⁄5 or less of a longitudinal length of the central non-integrated portion,
When the regions I to V are set in the diaper according to the following <Method for determining the regions I to V>, the central non-stacked portion and the line-symmetrical non-stacked portion exist in the regions II and III. Disposable diaper without axisymmetric non-accumulated part.
<Method of Determining Regions I to V>
In the unfolded and stretched diaper, one imaginary straight line extending in the lateral direction through the longitudinal end on the ventral side of the absorbent body is used as a reference line, and the dorsal side of the reference line Draw five virtual straight lines parallel to the reference line at equal intervals. The distance between the imaginary straight lines is set to a value obtained by dividing the length in the longitudinal direction from the longitudinal center line to the longitudinal end on the ventral side of the absorber by 5 and further doubling it. Regions divided into five by these six virtual straight lines are referred to as region I, region II, region III, region IV, and region V in order from the one closest to the reference line.

The disposable diaper as described in said <1> in which the said center non-accumulation part exists in <2> said area | region I and IV.
The disposable diaper as described in said <1> or <2> in which the said center non-accumulation part does not exist in <3> said area | region V. FIG.
<4> The disposable diaper according to any one of <1> to <3>, wherein the line-symmetrical non-stacking portion extends in the longitudinal direction.
<5> The lateral length of each of the central non-integrated portion and the line-symmetrical non-integrated portion is 5 mm or less, specifically, preferably 1 mm or more, more preferably 2 mm or more, and preferably 5 mm or less The disposable diaper according to any one of <1> to <4>, which is more preferably 4 mm or less.
<6> The longitudinal length of the central non-stacking portion is preferably 40% or more, more preferably 50% or more, and preferably 80% or less, with respect to the longitudinal length of the absorbent core. The disposable diaper any one of said <1>-<5> which is 70% or less preferably.
<7> The disposable diaper according to any one of <1> to <6>, wherein the longitudinal end of the central non-stacking portion does not reach the longitudinal end of the absorbent core.

<8> The above-mentioned absorber has the gradation area on which the basis weight of the absorber gradually increases in the lateral direction on both sides of the central non-accumulation part as it goes outward from the central non-accumulation portion in the lateral direction. The disposable diaper any one of <1>-<7>.
<9> The disposable diaper according to <8>, wherein a lateral length of the gradation area is longer than a lateral length of the central non-stacking portion.
<10> The lateral length of the gradation area is larger than a value obtained by doubling the lateral length of the central non-accumulated portion, and the magnitude relation of the former> (the latter × 2) holds Description disposable diaper.
<11> The ratio of the lateral length of the gradation region to the lateral length of the central non-accumulated part is preferably 2 or more, more preferably 5 or more, as the former / the latter, on the premise of the former> the latter. The disposable diaper as described in said <9> or <10> which is preferably 30 or less, more preferably 20 or less.

<12> The disposable diaper according to any one of <1> to <11>, in which a plurality of pairs of the line symmetrical non-stacking portions are intermittently arranged at equal intervals in the longitudinal direction.
<13> The longitudinal length of the line symmetrical non-accumulating part is preferably 1/6 or less, more preferably 1/8 or less, with respect to the longitudinal length of the central non-accumulating part. The disposable diaper any one of <12>.
<14> The longitudinal length of the axisymmetric non-stacking portion is preferably 3% or more, more preferably 4% or more, and preferably 40% or less, with respect to the longitudinal length of the absorbent core. The disposable diaper according to any one of the above <1> to <13>, which is more preferably 20% or less, more preferably 10% or less.
<15> The disposable according to any one of <1> to <14>, wherein the total number of the pair of linearly symmetrical non-accumulating portions present in the regions II and III is larger than that of the regions I and IV. Diapers.
<16> The total number of the pair of axisymmetric non-integrated parts present in the regions II and III is preferably 2 or more, more preferably 3 or more, and preferably 6 or less, more preferably 5 or less. The disposable diaper any one of said <1>-<15> which is it.
<17> The disposable diaper according to any one of <1> to <16>, wherein the total area of the line-symmetrical non-accumulating portions present in the regions II and III is larger than that of the regions I and IV. .

<18> The skin-side core wrap sheet and the non-skin-side core wrap sheet are each a non-woven fabric comprising fibers containing a polypropylene resin, and preferably a non-woven fabric consisting only of a polypropylene resin The disposable diaper of any one of 1>-<17>.
<19> Joining the skin-side core wrap sheet and the non-skin-side core wrap sheet in the area of the non-stacking portion in at least one, preferably all of the central non-stacking portion and the line-symmetrical non-stacking portion The joint occupancy rate, which is the proportion of the area of the part, is preferably 70% or more, more preferably 80% or more, and still more preferably 100% according to any one of the above <1> to <18>. Disposable diapers.
<20> In at least one, preferably all of the central non-stacked portion and the line-symmetrical non-stacked portion, a joint portion between the skin-side core wrap sheet and the non-skin-side core wrap sheet is a longitudinal portion of the non-stacked portion. The disposable diaper any one of said <1>-<19> continuous over the full length of the direction (longitudinal direction).
<21> The <1> to <11>, wherein the line-symmetrical non-integrating part exists at a position closer to the longitudinal end on the abdominal side of the absorber than the longitudinal end on the ventral side of the central non-accumulating part The disposable diaper any one of <20>.
<22> The basis weight of the surface sheet located in the region where the central non-stacked portion and the line-symmetrical non-stacked portion are present is preferably 30 g / m ² or more, more preferably 32 g / m ² or more, and preferably Is 50 g / m ² or less, more preferably 45 g / m ² or less, and the thickness of the surface sheet is preferably 1 mm or more, more preferably 1.5 mm or more, and preferably 8 mm or less, more preferably 6 mm or less The disposable diaper any one of said <1>-<21> which is it.

<23> The thickness of a portion other than the central non-integrated portion and the line-symmetrical non-integrated portion in the absorbent core is preferably 1 mm or more, more preferably 2 mm or more, and preferably 10 mm or less, more preferably 6 mm or less The disposable diaper any one of said <1>-<22> which is it.
<24> The basis weight of the portion other than the central non-accumulated portion and the line-symmetrical non-integrated portion in the absorbent core is preferably 50 g / m ² or more, more preferably 100 g / m ² or more, and preferably 400 g / ^{m 2} or less, more preferably a disposable diaper according to any one of the at 300 g / ^{m 2} or less <1> to <23>.
<25> In at least one, preferably all of the central non-integrated portion and the line-symmetrical non-integrated portion, the lateral length of the non-integrated portion is from the skin-facing surface of the absorber toward the non-skin-facing surface The disposable diaper any one of said <1>-<24> which is increasing gradually.
<26> The absorbent core has a constant-width portion whose lateral length is constant in the thickness direction of the absorbent core, and a lateral length is not from the skin-facing surface of the absorbent core (the absorber). And a tapered portion that gradually decreases toward the skin-facing surface, the tapered portion being laterally adjacent to the central non-integrated portion or the line-symmetrical non-integrated portion,
The absorbent core contains a fiber material and a water absorbent polymer as the absorbent material, and the content ratio of the fiber material to the water absorbent polymer in the tapered portion, that is, the mass of the fiber material / water absorption The disposable diaper according to any one of <1> to <25>, wherein the weight of the base polymer is lower than that in the constant width part.

DESCRIPTION OF SYMBOLS 1 disposable diaper F belly M side crotch R back 2 surface sheet 3 back sheet 4, 4A, 4B absorber 40 absorbent core 40A fixed width portion 40B taper portion 41 skin core wrap sheet 42 non-skin core wrap Sheet 4G gradation area 5 central non-accumulation part 6 line-symmetrical non-accumulation part X longitudinal direction Y lateral direction

Claims (10)

A liquid-retaining absorber and a surface sheet disposed on the skin-facing side of the absorber, wherein a longitudinal direction extending from the ventral side of the wearer to the dorsal side through the crotch and a lateral direction perpendicular thereto are In addition, it has a crotch portion disposed opposite to the crotch portion when worn, a ventral side portion disposed on the ventral side of the wearer rather than the crotch portion, and a ventral side disposed on the dorsal side of the wearer rather than the crotch portion. A disposable diaper having a back side
The absorbent body includes an absorbent core in which a core-forming material containing an absorbent material is accumulated, a non-woven skin side core wrap sheet covering the skin facing surface of the absorbent core, and a non-skin of the absorbent core. From the belly side to the back side across the longitudinal center line which is configured to include the non-skin side core wrap sheet made of non-woven fabric covering the opposite surface and which bisects the diaper in the unfolded and stretched state in the longitudinal direction Extends longitudinally across the
A plurality of non-accumulated portions of the core-forming material are formed in the absorbent core, and the skin-side core wrap sheet and the non-skin-side core wrap sheet are joined in each of the non-accumulation portions.
The plurality of non-integrated portions are a central non-integrated portion extending longitudinally in the lateral central portion of the absorbent core and a plurality of pairs of lines formed in line symmetry with the central non-integrated portion as an axis of symmetry. A longitudinal length of the axisymmetric non-integrated portion is 1⁄5 or less of a longitudinal length of the central non-integrated portion,
When the regions I to V are set in the diaper according to the following <Method for determining the regions I to V>, the central non-stacked portion and the line-symmetrical non-stacked portion exist in the regions II and III. Disposable diaper without axisymmetric non-accumulated part.
<Method of Determining Regions I to V>
In the unfolded and stretched diaper, one imaginary straight line extending in the lateral direction through the longitudinal end on the ventral side of the absorbent body is used as a reference line, and the dorsal side of the reference line Draw five virtual straight lines parallel to the reference line at equal intervals. The distance between the imaginary straight lines is set to a value obtained by dividing the length in the longitudinal direction from the longitudinal center line to the longitudinal end on the ventral side of the absorber by 5 and further doubling it. Regions divided into five by these six virtual straight lines are referred to as region I, region II, region III, region IV, and region V in order from the one closest to the reference line.   The disposable diaper according to claim 1, wherein the central non-accumulated portion exists in the regions I and IV.   The disposable diaper according to claim 1 or 2, wherein the central non-accumulated portion does not exist in the region V.   The disposable diaper according to any one of claims 1 to 3, wherein the line symmetrical non-stacking portion extends in the longitudinal direction.   The disposable diaper according to any one of claims 1 to 4, wherein the lateral length of each of the central non-stacking portion and the line-symmetrical non-stacking portion is 5 mm or less.   The said absorber has the gradation area | region where the basis weight of this absorber increases gradually as it goes to a lateral direction outward from this center non-accumulation part on the both sides of the center non-accumulation part laterally. The disposable diaper of any one of 5.   The disposable diaper according to any one of claims 1 to 6, wherein the total number of pairs of the line symmetrical non-accumulated portions present in the regions II and III is larger than that of the regions I and IV.   The disposable diaper according to any one of claims 1 to 7, wherein the total area of the line-symmetrical non-accumulated portions present in the regions II and III is larger than that of the regions I and IV.   The line-symmetrical non-integrating part is present at a position closer to the longitudinal end on the ventral side of the absorber than the longitudinal end on the ventral side of the central non-accumulating part. The disposable diaper according to item 1. The basis weight of the said surface sheet located in the area | region in which the said center non-stacking part and the said line symmetrical non-stacking part exist is 30 g / m < ² > or more, and thickness is 1 mm or more. Disposable diapers.

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