JP6202613B2 - Method for improving water absorption in absorbent articles - Google Patents

Description

  The present invention relates to a method for improving water absorption in absorbent articles such as disposable diapers and sanitary napkins.

Most disposable diapers are a part that extends from the lower abdomen through the crotch part to the buttocks along the center in the width direction, and a liquid-permeable top sheet that forms the body side surface; An absorbent main body part where the absorbent element is interposed between the liquid impervious sheet and a part extending to the waist side of the absorbent main body part and having no absorbent element It has a certain waist side portion and a side portion that is a portion that extends to the left and right sides of the absorbent main body portion and that does not have an absorbent element. In the so-called fastening type (tape type), fastening tapes are provided on both sides of the back side, and these fastening tapes are attached to the outer surface of the ventral side. is joined with both sides of both side portions and the ventral side, respectively, have the waist opening and leg openings are formed in advance, it performs the mounting by pulling up Ri girth through legs leg openings.

  In disposable diapers, the inner surfaces (skin-side surfaces) of the waist and side portions are usually formed of a hydrophobic or water-repellent nonwoven fabric, and are in close contact with the skin. May cause irritation and diaper rash due to stuffiness. Therefore, in order to solve this, it has been proposed to attach a sweat absorbing sheet to the inner surface of the diaper. (For example, refer to Patent Documents 1 and 2).

  However, the waist and side portions often have a structure in which a plurality of non-woven sheets are laminated. In such a case, in order to improve the sweat absorption and moisture absorption characteristics, each layer of non-woven fabric is made hydrophilic. It is necessary to improve the water absorption of the nonwoven fabric of each layer, for example, by containing an agent, and there is a problem that the manufacturing cost increases.

JP 2000-189454 A JP 2004-358099 A

  Then, the main subject of this invention is providing the method of improving the water absorption of a some laminated sheet easily and cheaply, and providing the absorbent article suitable for the method.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
Absorbent article comprising a laminated portion formed by laminating a second sheet made of hydrophobic or water-repellent fibers so as to come into contact with either the front or back side of the first sheet made of hydrophobic or water-repellent fibers A method for improving water absorption in
The laminated part is a stretchable part for fitting formed by fixing an elongated elastic stretchable member between the first sheet and the second sheet with an adhesive in a stretched state,
By laminating a second sheet not coated with a hydrophilizing agent on the first sheet coated with a hydrophilizing agent, the laminated portion is formed ,
When applying the hydrophilizing agent to the first sheet, the hydrophilizing agent is not applied to the portion through which the elongated elastic elastic member passes and the first sheet and the second sheet are laminated. In addition, the elongated elastic elastic member is fixed to the portion where the hydrophilic agent is not applied with an adhesive in an elongated state,
After you mow, held in a pressurized state for 6 hours or longer under a pressure 300 kg / m ² or more at least the stacked portion in a thickness direction,
The water absorption improvement method in the absorbent article characterized by the above-mentioned.

(Function and effect)
In the absorbent article, in a part where sweat absorption or moisture absorption is important, a hydrophilic agent is often applied to a nonwoven fabric made of hydrophobic or water-repellent fibers to improve water absorption. In such a case, as in the present invention, prior to laminating the first sheet and the second sheet, a hydrophilizing agent is applied only to the first sheet side and held in a pressurized state after lamination. Then, it seems that the hydrophilizing agent of the first sheet is probably transferred deeper into the second sheet (on the side opposite to the first sheet side), but the water absorption of the second sheet is improved. As a result, the water absorption of both sheets is improved. The phenomenon of improving water absorption, which seems to be due to the pressure transfer of such a hydrophilizing agent, was discovered unexpectedly. Since the present invention utilizes this phenomenon, the water absorption of a plurality of laminated sheets can be improved very easily and inexpensively. In other words, when purchasing and using a sheet fabric coated with a hydrophilizing agent, it is only necessary to purchase a sheet coated with the hydrophilizing agent on only one sheet, and the material cost is not increased. In addition, even if the hydrophilizing agent is applied in-line, there is an advantage that the number of application devices can be reduced. In addition to the application of the hydrophilizing agent, only pressure holding is performed, which is extremely easy.
On the other hand, in a pants-type disposable diaper, in order to improve the fit to the body, an elongated elastic elastic member such as rubber thread is fixed in an extended state at various locations in the exterior body to constitute a stretchable part for fitting Among them, a waist edge elastic elastic member along the width direction at the edge of the waist opening, and a waist lower elastic elastic member along the width direction at the crotch side than the waist edge elastic elastic member are provided. Some have a relatively high fit to the body and are widely used.
The tape-type disposable diaper includes a crotch part, a ventral part extending to the front side of the crotch part, a dorsal part extending to the back side of the crotch part, and a fastening projecting from both sides of the dorsal part. It has a tape and a target tape that is located on the outer surface of the abdomen and to which the fastening tape is connected. When wearing it on the body, turn the fastening tape from both sides of the waist to the outer surface of the abdomen and use it as the target tape. It has a structure to connect. Such a tape-type disposable diaper is used not only for infants but also widely used for nursing care (adult use). In general, tape-type disposable diapers are inferior to the waist-around fit of pants-type disposable diapers. For example, a stretchable elastic part is provided to provide a stretchable elastic part.
Since these stretchable parts for fitting are in close contact with the skin, sweat absorption and moisture absorption characteristics are important parts, but if a hydrophilic agent is applied to the position where the elastic stretchable member is fixed with an adhesive, adhesion will be insufficient. There is a possibility that the elastic elastic member is unfixed. Therefore, when applying the hydrophilizing agent to the fitting stretchable part, it is desirable not to apply the hydrophilizing agent to the portion through which the elastic stretchable member passes. In this case, it is necessary to align and adhere the elastic stretchable member to the non-application area of the hydrophilizing agent. However, in the present invention, the hydrophilizing agent is applied only to the first sheet. Is also easy.

<Invention of Claim 2>
Absorbent article comprising a laminated portion formed by laminating a second sheet made of hydrophobic or water-repellent fibers so as to come into contact with either the front or back side of the first sheet made of hydrophobic or water-repellent fibers A method for improving water absorption in
The absorbent article has an absorbent body interposed between a liquid-permeable surface sheet and a liquid-impermeable sheet, and is formed so as to cover from the back side through the crotch to the abdomen, A pants-type disposable diaper that includes an exterior body that is attached to at least front and rear waist edges on the outer surface of the interior body and that covers at least the waist.
By laminating the second sheet not coated with the hydrophilizing agent on the first sheet coated with the hydrophilizing agent, the exterior body having the laminated portion is formed, and at that time, the first sheet Application of the hydrophilizing agent to the sheet is not performed on the fixing region of the inner body in the outer body,
Thereafter, at least the laminated part is held in a state of being pressurized in the thickness direction at a pressure of 300 kg / m ² or more for 6 hours or more .
The water absorption improvement method in the absorbent article characterized by the above-mentioned .

(Function and effect)
In a pants-type disposable diaper, a structure in which an interior body is attached to the inner side of the exterior body is common, and conventionally, sweat absorption and moisture absorption in the exterior body have been a problem. Therefore, it is desirable to improve the water absorption of the present invention when forming the exterior body. However, since the portion overlapping the interior body is covered with the interior body, it contributes to sweat absorption and moisture absorption even when a hydrophilizing agent is applied. Can hardly be expected, and when the interior body is fixed to the exterior body with an adhesive, the adhesion may be insufficient due to the influence of the hydrophilizing agent. Therefore, as described above, it is desirable not to apply the hydrophilizing agent to the first sheet in the fixing region of the interior body in the exterior body.

<Invention of Claim 3>
The method for improving water absorption in an absorbent article according to claim 1 or 2, wherein the product produced by applying the hydrophilizing agent is held in the pressurized state by being packed in a product package bag.

(Function and effect)
Pressurization can be carried out on the production line using a continuous press such as a nip roll or other batch type press, but it is necessary to add a press to the production line, or a certain amount of time is required for pressurization. Therefore, in-line pressurization is not preferable. On the other hand, if a product manufactured by applying a hydrophilizing agent is packed in a product package bag and a sufficient pressure is applied to the product, it remains as it is without applying pressure on the production line. By simply packaging, storing and distributing the product, pressurization can be performed for a sufficient time in the process. Moreover, with this method, it is not necessary to add a pressurizing device to the facility.

<Invention of Claim 4 >
The at least one of the first sheet and the second sheet is a sheet exposed on an inner surface or an outer surface, and the hydrophilizing agent is applied only to a second sheet side surface of the first sheet. water improvement method in the absorbent article according to any one of 1 to 3.
(Function and effect)
Thus, by applying the hydrophilizing agent only to the opposing surfaces of the sheets, it becomes difficult for the hydrophilizing agent to adhere to the skin of the wearer or the person who touches the absorbent article.

  As described above, according to the present invention, there are advantages that a plurality of laminated sheets can be hydrophilized easily and inexpensively, and that the absorbent article is suitable for such hydrophilization.

It is a top view in the state where the diaper was developed showing the inside of a pants type disposable diaper. It is a top view in the state where the diaper was developed showing the outer surface of a pants type disposable diaper. FIG. 3 is a 3-3 cross-sectional view of FIG. 1. FIG. 4 is a sectional view taken along line 4-4 of FIG. It is (a) 5-5 sectional drawing of FIG. 1, (b) 6-6 sectional drawing. It is a top view in the state where the diaper was developed showing only the principal part of a pants type disposable diaper. It is sectional drawing which shows only the principal part of a pants type disposable diaper. It is a front view of a product state. It is a rear view of a product state. It is a top view in the state where the diaper was developed showing the outer surface of a pants type disposable diaper. It is (a) 5-5 sectional drawing of FIG. 10, (b) 6-6 sectional drawing. It is the schematic which shows a manufacturing flow in contrast. It is the schematic which shows a manufacturing flow in contrast. It is the schematic which shows a manufacturing flow in contrast. It is a perspective view which shows the example of a package. It is AA sectional drawing of FIG. It is a perspective view which shows the example of a package. It is a front view which shows the example of an arrangement | sequence in a package. It is a front view which shows the example of an arrangement | sequence in a package.

Hereinafter, the embodiment of the present invention will be described in detail with reference to an example of a pants-type disposable diaper.
<Example of pants-type disposable diapers>
1 to 9 show an example of a pants-type disposable diaper. This pants-type disposable diaper is composed of an exterior body 12 forming the outer surface (back surface) of the product and an interior body 200 attached to the inner surface of the exterior body. The interior body 200 is a part that absorbs and holds excrement such as urine, and the exterior body 12 is a part that is worn by the wearer.

  In addition, the dot pattern part in sectional drawing has shown the adhesive which joins each structural member, and is formed by solid, beads, curtains, summits, spiral application, etc., such as a hot-melt-adhesive. Instead of the adhesive, other joining means such as heat sealing and ultrasonic sealing can be used. The “front-rear direction” means a direction (vertical direction) connecting the ventral side (front side) and the back side (rear side), and “width direction” means a direction (left-right direction) orthogonal to the front-rear direction. .

(Interior body)
The interior body 200 can take any shape, but is rectangular in the illustrated form. As shown in FIGS. 3 to 5, the interior body 200 includes a surface sheet 30 on the body side, a liquid-impermeable sheet 11, and an absorption element 50 interposed therebetween. is there. Reference numeral 40 denotes an intermediate sheet (second sheet) provided between the top sheet 30 and the absorbent element 50 in order to quickly transfer the liquid that has passed through the top sheet 30 to the absorbent element 50. Shows a three-dimensional gather 60 that stands on the body side and is provided on both sides of the interior body 200 in order to prevent excrement from leaking to both sides of the interior body 200.

(Surface sheet)
The top sheet 30 has a property of transmitting liquid, and examples thereof include a porous or non-porous nonwoven fabric, a porous plastic sheet, and the like. Of these, the nonwoven fabric is not particularly limited as to what the raw fiber is. For example, synthetic fibers such as olefins such as polyethylene and polypropylene, polyesters and polyamides, recycled fibers such as rayon and cupra, natural fibers such as cotton, and mixed fibers and composite fibers using two or more of them. Etc. can be illustrated. Furthermore, the nonwoven fabric may be manufactured by any processing. Examples of the processing method include known methods such as a spunlace method, a spunbond method, a thermal bond method, a melt blown method, a needle punch method, an air through method, and a point bond method. For example, if flexibility and drapeability are required, the spunbond method and spunlace method are preferable. If bulkiness and softness are required, the air-through method, point bond method, and thermal bond method are preferable processing methods. .

  Further, the top sheet 30 may be composed of one sheet or may be composed of a laminated sheet obtained by bonding two or more sheets. Similarly, the top sheet 30 may be composed of one sheet or two or more sheets in the planar direction.

  When the three-dimensional gather 60 is provided, both sides of the top sheet 30 pass between the liquid-impermeable sheet 11 and the three-dimensional gather 60 to the back side of the absorbent element 50 to prevent the liquid from penetrating. It is preferable to adhere to the impermeable sheet 11 and the three-dimensional gather 60 with a hot melt adhesive or the like.

(Intermediate sheet)
In order to make the liquid which permeate | transmitted the surface sheet 30 transfer to an absorber rapidly, the intermediate | middle sheet (it is also called a second sheet) 40 whose liquid permeation | transmission speed is faster than the surface sheet 30 can be provided. This intermediate sheet 40 not only improves the absorption performance by the absorber by quickly transferring the liquid to the absorber, but also prevents the “reversed” phenomenon of the absorbed liquid from the absorber, and the surface sheet 30 is dried. It can be. The intermediate sheet 40 can be omitted.

Examples of the intermediate sheet 40 include the same material as the top sheet 30, spunlace, spunbond, SMS, pulp nonwoven fabric, mixed sheet of pulp and rayon, point bond, or crepe paper. In particular, an air-through nonwoven fabric is preferable because it is bulky. It is preferable to use a core-sheath composite fiber for the air-through nonwoven fabric. In this case, the resin used for the core may be polypropylene (PP), but polyester (PET) having high rigidity is preferable. Basis weight is preferably ^{20~80g / m 2, 25~60g / m} 2 is more preferable. The thickness of the raw fiber of the nonwoven fabric is preferably 2.2 to 10 dtex. In order to make the nonwoven fabric bulky, it is also preferable to use an eccentric fiber, a hollow fiber, or an eccentric and hollow fiber that does not have a core at the center as the mixed fiber of all or part of the raw fiber.

  The intermediate sheet 40 in the illustrated form is disposed in the center shorter than the width of the absorber 56, but may be provided over the entire width. The length of the intermediate sheet 40 in the longitudinal direction may be the same as the length of the absorbent body 56 or may be within a short length range centered on the region that receives the liquid.

(Liquid impervious sheet)
The material of the liquid-impermeable sheet 11 is not particularly limited. For example, a plastic film made of an olefin resin such as polyethylene or polypropylene, a laminated nonwoven fabric provided with a plastic film on the surface of the nonwoven fabric, or a plastic film For example, a laminated sheet in which a nonwoven fabric or the like is laminated and bonded to each other can be exemplified. For the liquid-impermeable sheet 11, it is preferable to use a liquid-impervious and moisture-permeable material that has been preferred in recent years from the viewpoint of preventing stuffiness. As a plastic film having moisture permeability, a microporous plastic film obtained by kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene, forming a sheet, and then stretching in a uniaxial or biaxial direction. Is widely used. In addition, non-woven fabric using micro-denier fibers, leakproof reinforcement by reducing the voids of the fibers by applying heat or pressure, and methods such as applying a superabsorbent resin or hydrophobic resin or water repellent Thus, a sheet that is liquid-impermeable without using a plastic film can also be used as the liquid-impermeable sheet 11.

  The liquid-impermeable sheet 11 is preferably extended around both sides of the absorbent element 50 to both sides of the side surface 30 of the absorbent element 50 in order to improve leakage prevention. The width of this extended portion is suitably about 5 to 20 mm on each of the left and right sides.

  Moreover, the excretion indicator from which a color changes by absorption of a liquid part can be provided in the inner side of the liquid-impermeable sheet 11, especially the absorber 56 side surface.

(Three-dimensional gather)
The three-dimensional gather 60 is a belt-like member that extends over the entire front-rear direction along both side portions of the interior body 200, blocks urine and soft stool that move in the lateral direction along the top sheet 30, and prevents side leakage. It is provided for this purpose. The three-dimensional gather 60 of the present embodiment is provided so as to stand up from the side portion of the interior body 200, the base side portion rises obliquely toward the center in the width direction, and the tip side portion from the intermediate portion has a width. It stands up diagonally outward in the direction.

  More specifically, the three-dimensional gather 60 folds the belt-shaped gather sheet 62 having a length equal to the length in the front-rear direction of the interior body 200 in the width direction and folds it into two. In addition, a plurality of elongated elastic elastic members 63 are fixed along the longitudinal direction at intervals in the width direction. An end portion of the three-dimensional gather 60 opposite to the folded portion in the width direction is an attachment portion 65 fixed to the back surface of the side edge portion of the interior body 200, and portions other than the attachment portion 65 protrude from the attachment portion 65. It is set as the protrusion part 66 (part by the side of a folding | turning part). Further, both end portions in the front-rear direction of the protruding portion 66 extend from the mounting portion 65 to the side surface of the topsheet 30 through the side portion of the interior body 200 and are hot-melted to the side surface of the topsheet 30. The base side portion is fixed to the front and rear fixing portion 67 by an adhesive or heat seal, and the tip side portion is folded back outward in the width direction from the tip of the base side portion and fixed to the base side portion. An intermediate part in the front-rear direction of the protruding part is an unfixed free part (inner free part), and an elongated elastic member 63 along the front-rear direction is fixed to the free part in an extended state.

The gather sheet 62 is made of a spunbond nonwoven fabric (SS, SSS, etc.), SMS nonwoven fabric (SMS, SSMMS, etc.), a melt-blown nonwoven fabric excellent in uniformity and concealment, and water-repellent with silicone as necessary. A treated product can be suitably used, and the fiber basis weight is preferably about 10 to 30 g / m ² . As the elongated elastic elastic member 63, rubber thread or the like can be used. When spandex thread rubber is used, the thickness is preferably 470 to 1240 dtex, more preferably 620 to 940 dtex. The elongation rate at the time of fixation is preferably 150 to 350%, more preferably 200 to 300%. The term “elongation rate” means a value when the natural length is 100% (the same applies hereinafter). Moreover, as shown in the drawing, a waterproof film can be interposed between the gather sheets folded in two.

  2-6 are preferable and, as for the number of the elongate elastic expansion-contraction members 63 provided in the free part of the three-dimensional gather 60, 3-5 are more preferable. The arrangement interval 60d is suitably 3 to 10 mm. If comprised in this way, in the range which has arrange | positioned the elongate elastic expansion-contraction member 63, it will become easy to contact | abut with respect to skin. The elongated elastic elastic member 63 may be disposed not only at the distal end side but also at the base side.

  The fixing target of the attachment portion 65 of the three-dimensional gather 60 can be an appropriate member such as the top sheet 30, the liquid-impermeable sheet 11, and the absorbent element 50 in the interior body 200.

  In the three-dimensional gather 60 thus configured, the contraction force of the elongated elastic elastic member 63 acts so that both ends in the front-rear direction are brought close to each other, but the both ends in the front-rear direction of the protruding portion 66 are fixed so as not to stand up. On the other hand, since they are non-fixed free portions, only the free portions stand up against the body side as shown in FIG. In particular, when the attachment portion 65 is positioned on the back surface side of the interior body 200, the three-dimensional gather 60 stands up so as to open outward in the width direction at the crotch portion and in the vicinity thereof. It comes in contact, and the fit is improved.

  The dimensions of the three-dimensional gather 60 can be determined as appropriate. In the case of an infant paper diaper, for example, as shown in FIG. 7, the standing height of the three-dimensional gather 60 (the length in the width direction of the protruding portion 66 in the unfolded state) W6 is It is preferably 15 to 60 mm, particularly 20 to 40 mm. In addition, the distance W3 between the folds located on the innermost side in a state where the three-dimensional gather 60 is folded flat so as to be parallel to the surface of the top sheet 30 is preferably 60 to 190 mm, particularly preferably 70 to 140 mm.

  Note that, unlike the illustrated embodiment, the three-dimensional gathers can be provided in double (two rows) on the left and right sides of the interior body 200.

(Absorption element)
The absorbent element 50 includes an absorbent body 56 and a packaging sheet 58 that wraps the entire absorbent body 56. The packaging sheet 58 can be omitted.

(Absorber)
The absorber 56 can be formed of an aggregate of fibers. As this fiber assembly, a filament assembly obtained by opening, as necessary, synthetic fiber tows (fiber bundles) such as cellulose acetate as well as short fibers such as cotton-like pulp and synthetic fibers Can also be used. The fiber basis weight can be set to, for example, about 100 to 300 g / m ² when cotton-like pulp or short fibers are stacked, and in the case of a filament aggregate, for example, about 30 to 120 g / m ^2. Can do. The fineness in the case of a synthetic fiber is 1-16 dtex, for example, Preferably it is 1-10 dtex, More preferably, it is 1-5 dtex. In the case of a filament aggregate, the filament may be a non-crimped fiber, but is preferably a crimped fiber. The degree of crimp of the crimped fibers can be, for example, about 5 to 75, preferably 10 to 50, and more preferably about 15 to 50 per 2.54 cm . Further, a crimped fiber that is uniformly crimped is often used. It is preferable to disperse and hold superabsorbent polymer particles in the absorber 56.

The absorber 56 may have a rectangular shape, but as shown in FIG. 1, as shown in FIG. 1, the hourglass has a front end portion, a rear end portion, and a narrow portion narrower than the front end portion and the rear end portion. If has a shape, the absorbent body 56 itself and the three-dimensional gathers 60, is improved, which is preferable fit of the leg circumferential Rie.

  Moreover, although the dimension of an absorber can be determined suitably, it is preferable to extend to the peripheral part of the interior body, or its vicinity in the front-back direction and the width direction.

(Superabsorbent polymer particles)
The absorber 56 can contain superabsorbent polymer particles in a part or all thereof. Superabsorbent polymer particles include “powder” in addition to “particles”. As the particle diameter of the superabsorbent polymer particles, those used in this type of absorbent article can be used as they are, and those having a particle size of 1000 μm or less, particularly 150 to 400 μm are desirable. The material of the superabsorbent polymer particles can be used without any particular limitation, but those having a water absorption of 40 g / g or more are suitable. High-absorbency polymer particles include starch-based, cellulose-based, and synthetic polymer-based starch-acrylic acid (salt) graft copolymers, saponified starch-acrylonitrile copolymers, and sodium carboxymethylcellulose crosslinks. Or an acrylic acid (salt) polymer can be used. As the shape of the superabsorbent polymer particles, a commonly used granular material is suitable, but other shapes can also be used.

  As the superabsorbent polymer particles, those having a water absorption rate of 40 seconds or less are preferably used. When the water absorption speed exceeds 40 seconds, so-called reversion in which the liquid supplied into the absorber 56 returns to the outside of the absorber 56 is likely to occur.

  Further, as the superabsorbent polymer particles, those having a gel strength of 1000 Pa or more are preferably used. Thereby, even if it is a case where it is set as the bulky absorber 56, the sticky feeling after liquid absorption can be suppressed effectively.

The basis weight of the superabsorbent polymer particles can be appropriately determined according to the amount of absorption required for the use of the absorber 56. Therefore, although it cannot be said unconditionally, it can be set to 50 to 350 g / m ² . If the amount of polymer is less than 50 g / m ^2, it is difficult to secure the absorption amount. When it exceeds 350 g / m ² , the effect is saturated.

  If necessary, the superabsorbent polymer particles can adjust the spraying density or spraying amount in the plane direction of the absorber 56. For example, it is possible to increase the application amount of the liquid excretion site as compared to other sites. When gender differences are taken into account, men can increase the front spray density (amount), while women can increase the center spray density (amount). In addition, a portion where no polymer exists locally (for example, in a spot shape) in the planar direction of the absorber 56 can also be provided.

(Packaging sheet)
When the packaging sheet 58 is used, as the material, tissue paper, particularly crepe paper, non-woven fabric, polylaminated non-woven fabric, a sheet with small holes, or the like can be used. However, it is desirable that the superabsorbent polymer particles be a sheet that does not escape. When a nonwoven fabric is used in place of the crepe paper, a hydrophilic SMS nonwoven fabric (SMS, SSMMS, etc.) is particularly suitable, and the material can be polypropylene, polyethylene / polypropylene composite material, or the like. The basis weight is preferably 5 to 40 g / m ² , particularly 10 to 30 g / m ² .

  The packaging form of the packaging sheet 58 can be determined as appropriate, but from the viewpoint of ease of manufacture and prevention of leakage of the superabsorbent polymer particles from the front and rear end edges, the cylinder is formed so as to surround the front and back surfaces and both side surfaces of the absorbent body 56. It is preferable that the front and rear edges of the absorbent body 56 are protruded from the front and back of the absorbent body 56, and the protruding portions are crushed in the front and back directions and joined by a joining means such as a hot melt adhesive.

(Exterior body)
The exterior body 12 has a ventral part F extending from the crotch part to the ventral side and a dorsal part B extending from the crotch part to the dorsal side. As shown in FIGS. 8 and 9, a pair of left and right leg openings LO for passing the legs and a torso opening WO for passing the wearer's torso are formed. Is. Reference numeral 12A denotes a joining portion (hereinafter, this portion is also referred to as a side seal portion). The crotch portion means a portion corresponding to the crotch of the wearer, and is usually a portion including the center in the front-rear direction. Further, the front part and the rear part from the center in the front-rear direction are the ventral part F and the back part B.

  The exterior body 12 has a trunk periphery T that is determined as a front-rear direction range from the trunk opening WO to the upper end of the leg opening LO, and an intermediate portion L that is determined as a front-rear direction range of a portion that forms the leg opening LO. The waistline portion T can be conceptually divided into a waist edge portion W and a waist lower portion U. The length in the front-rear direction varies depending on the size of the product and can be determined as appropriate. For example, the waist edge W may be 15 to 40 mm, and the waist lower portion U may be 65 to 120 mm. On the other hand, both side edges of the intermediate portion L are bundled along the circumference of the wearer's leg, and this is a portion into which the wearer's leg is put. In other words, the unfolded exterior body 12 has a substantially hourglass shape as a whole. The degree of tightness of the exterior body 12 can be determined as appropriate, and, as shown in FIGS. 1 to 9, in order to obtain a clean appearance, the narrowest part is narrower than the width of the interior body 200, Even the narrowest part can be determined to be equal to or larger than the width of the interior body 200. Further, as shown in FIGS. 10 and 11, the exterior body 12 of the abdominal part and the exterior body 12 of the back part are not continuous on the crotch side, and may be separated from each other. In this case, the crotch outer sheet 12M can be attached so as to cover a portion of the outer surface of the inner body 200 that is exposed between the outer body 12 of the abdomen and the outer body 12 of the back part.

As shown in FIGS. 3 to 5, the exterior body 12 is formed by laminating an inner sheet 12H and an outer sheet 12S and bonding them with an adhesive such as a hot melt adhesive, and is located on the inner side. 12H extends only to the edge of the waist opening WO, but the outer sheet 12S wraps around the edge on the waist side of the inner sheet 12H and is folded back inside. It extends to cover up to the waist edge. The outer sheet 12S is continuous from the back side to the ventral side, but the inner sheet 12H is provided with a portion located on the back side and a part located on the ventral side separately, The whole (or a part thereof) is located in the front-rear direction range L corresponding to the leg opening LO. This distance between spaced-apart portions can be decided as appropriate, the inner sheet 12H is a resilient and elastic members 15 to 19 which exhibits a clamping function to be described later girth up direction, and held between the inner surface of the outer sheet 12S Therefore, it is preferable to provide at least a portion having the elastic elastic members 15 to 19.

Since this embodiment applies the water absorption improvement of this invention with respect to the exterior body 12, the nonwoven fabric which consists of a hydrophobic or water-repellent fiber is used as the inner sheet | seat 12H and the outer sheet | seat 12S. Of course, when the water absorption improvement of this invention is not applied with respect to the exterior body 12, as the sheet | seat 12S, 12H used for the exterior body 12, if it is a sheet, it can be used without a limitation, However, It is preferable that it is a nonwoven fabric. The nonwoven fabric is not particularly limited as to what the raw fiber is. For example, synthetic fibers such as olefins such as polyethylene and polypropylene, polyesters and polyamides, recycled fibers such as rayon and cupra, natural fibers such as cotton, and mixed fibers and composite fibers using two or more of them. Etc. can be illustrated. Furthermore, the nonwoven fabric may be manufactured by any processing. Examples of the processing method include known methods such as a spunlace method, a spunbond method, a thermal bond method, a melt blown method, a needle punch method, an air through method, and a point bond method. When using a nonwoven fabric, it is preferable that the basic weight shall be about 10-30 g / m < ² >.

Then, the exterior body 12, in order to increase the girth Rinitaisuru fit, both sheets 12S, elongated resilient and elastic members 15 to 19 rubber threads are used between 12H is fixed at a predetermined extension ratio. As the elongated elastic elastic members 15 to 19, synthetic rubber or natural rubber may be used. For bonding the sheets 12S and 12H of the exterior body 12 and fixing the elongated elastic elastic members 15 to 19 sandwiched therebetween, hot melt bonding or heat sealing or ultrasonic bonding by various coating methods can be used. . If the entire exterior body 12 is firmly fixed, the texture of the sheet is impaired, which is not preferable. By combining these, it is preferable that the elongated elastic elastic members 15 to 19 are firmly bonded, and other portions are not bonded or bonded weakly.

More specifically, the entire width direction is between the inner surface of the inner sheet 12H and the outer surface of the folded portion 12r of the outer sheet 12S at the waist end (upper end) W of the back portion B and the ventral portion F. A plurality of waist elastic elastic members 17 and 18 are fixed in a state where they are extended in the width direction at a predetermined extension rate with a space therebetween in the vertical direction so as to be continuous. In addition, one or a plurality of the waist elastic elastic members 17 and 18 disposed in the region adjacent to the waist lower portion U may overlap with the interior body 200 or may overlap with the interior body 200. You may each provide in the width direction both sides except a direction center part. As the waist resilient and elastic members 17 and 18, the thickness 155～1880Dtex, particularly about 470～1240Dtex (the case of synthetic rubber. Cross-sectional area in the case of natural rubber 0.05 to 1.5 mm ^2, in particular 0.1 the rubber thread of 1.0mm about ^2), 3 to 22 present approximately at intervals of 4 to 12 mm, respectively elongation from 150% to 400%, preferably fixed in particular about 220-320%. The waist elastic elastic members 17 and 18 need not all have the same thickness and elongation rate. For example, the elastic elastic members may have different thicknesses and elongation rates at the upper and lower portions of the waist edge W. Good.

  Also, the upper side of the lower side U of the ventral portion F and the back portion B is located between the outer side surface of the inner sheet 12H and the inner side surface of the outer sheet 12S except for the central portion in the width direction overlapping the interior body 200. A plurality of elongated elastic elastic members 15 and 19 are extended along the width direction at a predetermined extension rate at intervals in the vertical direction so as to be continuous over the entire width direction at each part on both sides in the width direction. It is fixed in the state.

The elongated elastic elastic members 15 and 19 at the lower waist U have a thickness of 155 to 1880 dtex, particularly about 470 to 1240 dtex (in the case of synthetic rubber. In the case of natural rubber, a cross-sectional area of 0.05 to 1.5 mm ² , the rubber thread 0.1~1.0mm about ^2), 1 to 15 mm, particularly 5 to 30 present approximately at intervals of 3 to 8 mm, to secure each elongation 200-350%, in particular about 240-300% Is preferred.

  Further, the width between the outer side surface of the inner sheet 12H and the inner side surface of the outer sheet 12S in the middle part L of the ventral part F and the back part B, except for the central part in the width direction that overlaps the interior body 200, is the width. A plurality of elongated elastic elastic members 16 are fixed to each part on both sides of the direction in the width direction so as to be continuous over the entire width direction and spaced along the width direction at a predetermined elongation rate. Has been.

The slender elastic elastic member 16 of the intermediate portion L has a thickness of 155 to 1880 dtex, especially about 470 to 1240 dtex (in the case of synthetic rubber. In the case of natural rubber, the cross-sectional area is 0.05 to 1.5 mm ² , especially 0. 1 to 1.0 mm ² ) is preferably fixed at an interval of 5 to 40 mm, particularly 5 to 20 mm, and about 2 to 10 at an elongation of 150 to 300%, particularly 180 to 260%.

  As shown in the figure, the elongated elastic elastic members 15, 19, 16, and 18 of the waist lower part U and the intermediate part L are provided on both sides in the width direction except for the center part in the width direction overlapping the interior body 200. It is preferable that the interior body 200 does not shrink more than necessary in the width direction, and it does not look bad and does not deteriorate absorbability. In this form, in addition to the form in which the elastic stretchable member exists only on both sides in the width direction, the elastic stretchable member exists from one side of the width direction to the other side across the interior body 200, but overlaps the interior body 200. A configuration is also included in which the elastic stretchable member is cut at the center in the width direction so that the stretchable force does not act (substantially equivalent to not providing the elastic stretchable member). Of course, the arrangement form of the elongated elastic expansion / contraction members 15, 19, 16, 18 is not limited to the above example, and the elongated elastic expansion / contraction of the lower waist portion U so that the expansion / contraction force acts on the entire width direction of the lower waist portion U. Part or all of the members 15, 19, 16, and 18 can be provided from one side in the width direction to the other side across the interior body 200.

(About hydrophilizing agent)
Characteristically, in the region Z from the waist lower part U which is the expansion / contraction part for fitting in the exterior body 12 to the waist side part of the intermediate part L, the hydrophilizing agent 20 is contained in both the inner sheet 12H and the outer sheet 12S. Yes. Thereby, the water absorption of the exterior body 12 improves, and the sweat absorption and moisture absorption in the exterior body 12 improve. In addition, in the state in which the hydrophilizing agent 20 is contained in the sheets 12H and 12S, either the front or back of the sheets 12H and 12S, in addition to the form in which the hydrophilizing agent 20 is contained in the entire thickness direction of the sheets 12H and 12S. The form contained only on one side is also included. As can be understood from this description, one of the inner sheet 12H and the outer sheet 12S corresponds to the first sheet of the present invention, and the other sheet corresponds to the second sheet.

In order to prevent the hydrophilic agent 20 from adhering to the skin, it is desirable that the inner surface of the inner sheet 12H has little or no hydrophilic agent 20 at all. Further, the content of the hydrophilizing agent 20 in the outer sheet 12S may be more or less than the content of the hydrophilizing agent 20 in the inner sheet 12H. When water repellent treatment with silicone or the like is performed on the target portion for improving water absorption, if the water repellent treatment is performed on the inner surface of the inner sheet 12H that is a skin side sheet, the adhesion of the hydrophilizing agent 20 to the skin can be prevented. This is preferable because it is possible.

  The stretchable part for fitting is a part that is in close contact with the skin, and since sweat absorption and moisture absorption characteristics are important parts, it may be possible to include the hydrophilizing agent 20 on the entire surface, but the elastic stretchable members 15, 19, 16 are bonded. If the hydrophilizing agent 20 is contained in the fixing position, the adhesion becomes insufficient, and the elastic elastic members 15, 19, 16 may be unfixed. Therefore, as shown in FIG. 2, it is desirable not to contain the hydrophilizing agent 20 in the part where the elastic elastic members 15, 19, and 16 pass. In this case, as shown in FIG. 2, the containing part of the hydrophilizing agent 20 is provided only in the vertical direction with an interval (that is, provided in a horizontal stripe shape), and the elastic elastic members 15, 19, In addition to fixing 16 with a hot-melt adhesive, as shown in FIG. 10, the portion containing the hydrophilizing agent 20 is provided only intermittently in both the longitudinal direction and the width direction (that is, provided in a dot pattern). ), Elastic elastic members 15, 19, and 16 can be fixed to the non-containing portion between them with a hot melt adhesive.

  Moreover, since the part which overlaps with the interior body 200 among the exterior bodies 12 is coat | covered with the interior body 200, even if it applies the hydrophilizing agent 20, the contribution to sweat absorption and moisture absorption can hardly be expected, and the interior body 200 is adhered. When fixing to the exterior body 12 with an agent, the adhesion may be insufficient due to the influence of the hydrophilizing agent 20. As shown in FIGS. 2 and 3, it is desirable that the hydrophilizing agent 20 is not contained in the fixing region of the inner body 200 in the outer body 12.

When both the inner sheet 12H and the outer sheet 12S are subjected to a water repellent treatment with silicone or the like, at the fixed position of the elastic elastic members 15, 19, 16 together with the intermittent application of the hydrophilic agent 20 described above. Water treatment is preferable because it is difficult for moisture to move from the water-absorbing portion by the hydrophilizing agent 20 to the hot melt adhesive, and a decrease in adhesive force due to the hot melt adhesive becoming wet can be prevented.

  In the illustrated embodiment, the waist edge W does not contain the hydrophilizing agent 20, but the waist edge W can contain the hydrophilizing agent 20 instead of or along with the region Z1.

  The material of the outer package 12 is not particularly limited, but since the hydrophilizing agent 20 is used, a nonwoven fabric made of water-repellent or hydrophobic fibers or a water-repellent or hydrophobic resin film is suitable.

  As the hydrophilizing agent 20, in consideration of safety to the human body, safety in the process, etc., a nonionic active agent to which ethylene oxide such as higher alcohol, higher fatty acid, alkylphenol or the like is added, alkyl phosphate ester salt ( Octyl, dodecyl), anionic surfactants such as alkyl sulfates or the like are preferably used alone or as a mixture, and the amount to be applied varies depending on the required performance, but is usually 0. It is desirable that the amount be about 1 to 2.0 wt%, particularly about 0.2 to 1.0 wt%.

<About water absorption improvement method>
Next, a method for improving water absorption will be described based on a manufacturing example of a pants-type disposable diaper shown in FIGS. Each of FIG. 12 to FIG. 14 schematically shows a state change when a pant-type disposable diaper in which the plan view of the upper stage part is substantially the same as the form shown in FIG. 1 to FIG. The state change at the time of manufacturing the underpants type disposable diaper substantially the same as the form shown in FIG.10 and FIG.11 is shown, the front view of the lower stage part has shown the equipment flow, and it has arranged so that a process can be compared.

More specifically, this pant-type disposable diaper manufacturing method includes an exterior body forming step 501, an elastic elastic member cutting step 502, a leg opening separation step 503, an interior body attaching step 504, a side joining step 505, and A separation step 506 is included. First, the exterior body forming step 501, by feeding the outer sheet 12S and inner sheet 12H continuous strip from the rolls, the sheets 12S, Ri the resilient and elastic members 15 to 19 of the thread rubber or the like conveying direction (girth between 12H The exterior body 12 is continuously formed by sequentially bonding the two sheets 12S and 12H with a hot melt adhesive or the like while sandwiching them in a state of extending along the direction).

  Next, in the elastic expansion / contraction member cutting step 502, the elastic expansion / contraction members 15, 16, and 19, which are located in the portion CT that overlaps with the internal body 200 later, are removed from the formed continuous exterior body 12 by a cutting device 601 such as heat embossing. It cut | disconnects and it is set as the state which the expansion-contraction force of the elastic expansion-contraction members 15, 16, and 19 does not act in the said part CT. Further, in the next leg opening separation step 502, the portion LB which becomes the leg opening of the diaper adjacent in the continuous direction (conveying direction (MD direction)) is made into an integral hole by a cutting device such as the die cutter 602. Punching and separating from the main part, which is the part that becomes the diaper That is, the portion LB that becomes the leg opening is cut off as one piece. Thereby, a leg opening LO is formed. Thereafter, in the mounting process 504 of the interior body 200, the interior body 200 manufactured in another line is supplied and intermittently pasted on the continuous strip-shaped exterior body 12 that is sequentially conveyed by a hot melt adhesive or the like. It is done.

  Next, in the side part joining step 505, one side in the CD direction is folded to the other side, the abdomen part and the back part are overlapped, and joined by a joining device 603 such as heat seal at a predetermined interval in the MD direction. Processing is performed, and the ventral portion and the back portion are joined at the portion 12A, which is the both side portions in the width direction of each diaper. After that, in the last separation step 506, the cutting device 604 has a predetermined interval in the MD direction, and a boundary between portions that become individual diapers (a joint portion 12A of one diaper among adjacent diapers and the other) Are located between the diaper joints 12A) to obtain individual diapers.

  Characteristically, in the form shown in FIG. 12, after applying the hydrophilizing agent 20 to the outer sheet 12S by the hydrophilizing agent applying device 12C, the inner sheet 12H to which the hydrophilizing agent 20 is not applied is laminated and bonded (in this case, The outer sheet 12S corresponds to the first sheet of the present invention, and the inner sheet 12H corresponds to the second sheet of the present invention). Instead, as shown in FIGS. 13 and 14, after applying the hydrophilizing agent 20 to the inner sheet 12H by the hydrophilizing agent applicator 12C, the outer sheet 12S to which the hydrophilizing agent 20 is not applied is laminated. The outer sheet 12S may correspond to the second sheet of the present invention, and the inner sheet 12H may correspond to the first sheet of the present invention. The example of the hydrophilizing agent 20 and the coating amount may be as described above. In the illustrated embodiment, the hydrophilizing agent 20 is applied in-line by the hydrophilizing agent coating apparatus 12C, but it is also possible to purchase and use the sheet raw material to which the hydrophilizing agent 20 has been applied. The agent coating device 12C is not necessary. As the hydrophilizing agent 20 coating device, a known contact-type coating device such as roll transfer can be used in addition to a known non-contact coating method such as spray coating.

  Then, after the two sheets 12H and 12S are laminated and adhered, in the present invention, at least the laminated portion is held in a pressurized state in the thickness direction, and the sheet without the hydrophilizing agent 20 applied (in the form shown in FIG. 12, the inner sheet). 12H, the form shown in FIGS. 13 and 14 improves the water absorption of the outer sheet 12S). This pressurization can be carried out in the production line by a continuous press device such as a nip roll or other batch type press device. However, it is necessary to add a press device to the production line or to some extent in pressurization. Therefore, in-line pressurization is not preferable. Therefore, it is recommended that a product manufactured by applying the hydrophilizing agent 20 is packed in a product package bag so that a sufficient pressure is applied to the product. As a result, even if no pressure is applied on the production line, the product is simply packaged, stored and distributed as it is, and sufficient pressure is applied in the process to ensure improved water absorption. Become.

  The product package is not particularly limited. For example, FIGS. 15 and 16 show an example of the package bag 101 of the absorbent article 100. This package bag 101 is a so-called side fold type gusset bag, and both ends in the width direction of the package material formed in a cylindrical shape are folded inward by folds 102c along the longitudinal direction to form a town and cut into a predetermined length. The upper end portion 107 (the upper end edge and the lower end edge of the upper end portion 107 in the illustrated example) is sealed by fusion or adhesion. At the time of packaging, the article is inserted from the lower end portion 108 and the upper end edge (boundary line between the lower end portion 108 and the lower surface 106) of the lower end portion 108 is sealed to form a rounded substantially rectangular parallelepiped package bag. Thus, left and right side surfaces 102, front surface 103, rear surface 104, upper surface 105, and lower surface 106 are formed. In addition, a handle hole 109 for passing a hand in the front-rear direction is formed in an upper end portion 107 formed by sealing the upper and lower end edges. FIG. 17 shows another example of the package bag 101 of the absorbent article. This package bag is formed by folding a sheet-like package material in half and forming a gusset by folding the fold 105c inward to form a gusset bag with both sides sealed, and a vertical surface (both sides) 102 and the front and rear surfaces 103, 104) are formed, and both end portions of the hand loop 130 are attached to the front and rear rib portions 132 by appropriate coupling means such as fusion. A form (not shown) in which the front and rear ribs and the handbag loop are omitted from this form is also employed in the absorbent article. In these upper-folding gusset bags, the article is inserted from the lower end portion 8 during packaging, and the upper end edge of the lower end portion 108 (the boundary line between the lower end portion 108 and the lower surface 106) is sealed to form a substantially rectangular parallelepiped shape. It becomes a package bag.

  Inside the package bag 101, absorbent articles 100 such as pants-type, tape-type, pad-type disposable diapers and sanitary napkins are accommodated in an appropriate arrangement state. As for such an absorbent article 100, a small thing is packaged without being folded, while a large thing is packaged in a flat state in which the front and back are folded in two or the front and rear are folded in the center. In some cases, it may be folded into four or more folds and packaged. In addition, since both sides of the front body and the back body are joined, the pants-type disposable diaper is already folded in two with respect to the center in the front-rear direction in the product state. Is. Moreover, when the side flap which protrudes large like a sanitary napkin is provided, a side flap may be folded inward along the absorber side part vicinity. In the package of the absorbent article 100, a large number of such absorbent articles 100 are gathered, and an assembly obtained by overlapping and compressing the flat parts so as to match each other is packed in one or more stages in a package bag, and in a pressurized state. Packaging. In this case, it is preferable to package the diaper so that the plane direction of the diaper is parallel to the side surface of the package bag 101 as shown in the figure, but the front and rear direction of the diaper is either the vertical direction or the depth direction of the package bag 101. You may come along.

  The folding method and arrangement of the absorbent article 100 can be determined as appropriate, but the folding method and arrangement of the absorbent article 100 should be devised so that the pressure acts more reliably on the application region of the hydrophilizing agent 20. Is also preferable. For example, as shown to Fig.18 (a), in the state which folded the absorbent article 100 about the center in the front-back direction (equivalent to the product state which is not folded in a pants type disposable diaper. The following is the same), the bending end part 110 And the non-bending end portions (front and rear end portions) 111 are alternately stacked so that the portion on the bent end portion 110 side becomes thicker than the non-bending end portion 111. It is preferable because a stronger pressure is applied to a portion sandwiched between the waists (a waist side portion where sweat absorption is particularly important in a pants-type disposable diaper), and the transfer of the hydrophilizing agent is ensured. Further, as shown in FIG. 18 (b), the absorbent article 100 folded in half in the front-rear direction is further folded in only one side in the front-rear direction to provide a double part 112 and a quadruple part 114. When the absorbent article 100 is alternately stacked so that the steps are combined, more pressure is applied to the portion between the thick quadruple portions 114 of the adjacent absorbent article 100, and the transfer of the hydrophilizing agent is ensured. Therefore, it is preferable. Further, as shown in FIG. 19, even when the absorbent article 100 is folded in a state of being substantially W-shaped in cross section, the quadruple portion 114 is formed, so that the quadruple portion 114 of the absorbent article 100 on both sides is formed. This is preferable because a stronger pressure is applied to the sandwiched portion, and the transfer of the hydrophilizing agent is surely performed. In addition, the hatched part in FIG. 19 shows a cross section.

As a material of the package bag 101, a plastic film usually used for a package such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), nylon, etc. can be used alone or as a composite material. In the field of absorbent articles, polyethylene films are preferred because they are widely used. Among them, LDPE (low density polyethylene: density 0.900 to 0.925 g / cm ³ ) and MDPE (medium density polyethylene: density 0. 925 to 0.940 g / cm ³ ) is preferred. The thickness of the film is preferably about 50 to 100 μm. The material of the package bag is generally a plastic film, but a sheet material such as paper or nonwoven fabric or a composite material of these materials may be used.

The pressurizing conditions can be determined as appropriate. When the inner sheet 12H and the outer sheet 12S are nonwoven fabrics made of hydrophobic or water-repellent fibers usually used in absorbent articles, the pressure is 300 kg / m ² or more for 6 hours. It is desirable to perform the pressurization as described above, and it is particularly desirable to perform the pressure at a pressure of about 300 to 500 kg / m ² for 24 hours or more. In addition, if it is this pressurization condition, it is also possible to pack a diaper in a product package bag.

  As described above, when the phenomenon of improving water absorption by pressurization is used, a pants-type disposable diaper (details of structure and the like) that improves the water absorption of both the inner sheet 12H and the outer sheet 12S of the exterior body 12 very easily and inexpensively. Can refer to the form shown in FIGS. 1 to 11 and the description thereof. That is, when purchasing and using a sheet raw material to which the hydrophilizing agent 20 has been applied, it is only necessary to purchase a sheet coated with the hydrophilizing agent 20 on only one of the sheets, so that the material cost does not increase. In addition, even if the hydrophilizing agent 20 is applied in-line, there is an advantage that the number of application devices can be reduced. In addition to the application of the hydrophilizing agent 20, only pressure holding is performed, which is extremely easy.

  When the hydrophilizing agent 20 is applied to the inner sheet 12H or the outer sheet 12S, the hydrophilizing agent 20 can be applied to the inner surface or the outer surface exposed to the diaper, but the wearer or the person who touches the absorbent article. Since the hydrophilizing agent 20 may adhere to the skin of the skin, in order to prevent or suppress this, the hydrophilic property is applied only to the surface on the inner sheet 12H side in the outer sheet 12S or the surface on the outer sheet 12S side in the inner sheet 12H. It is desirable to apply the agent 20. Thereby, as described above, the inner surface of the inner sheet 12H has little or no hydrophilizing agent 20, and the hydrophilizing agent 20 adheres to the skin of the wearer or the person who touches the absorbent article at least in the initial use. It will be difficult.

  In particular, as shown in the figure, when the application site of the hydrophilizing agent 20 is a site where the elastic elastic members 15, 19, 16 are fixed with an adhesive to form a fitting elastic part, If the hydrophilizing agent 20 is applied at a position where the 19, 16 is fixed by an adhesive, the adhesion becomes insufficient, and the elastic elastic members 15, 19, 16 may be unfixed. Therefore, in this case, when applying the hydrophilizing agent 20, the hydrophilizing agent 20 is not applied to the portion through which the elongated elastic elastic members 15, 19, 16 pass, and both sheets 12H, 12S are attached. When laminating, it is desirable to fix the elongated elastic elastic members 15, 19, 16 to the portion where the hydrophilizing agent 20 is not applied with an adhesive in an extended state. Thereby, the underpants type disposable diaper of the hydrophilizing agent 20 application pattern shown in FIG.2 and FIG.10 can be manufactured. In this case, it is necessary to align and bond the elastic stretch members 15, 19, 16 to the non-application area of the hydrophilizing agent 20, but in the present invention, one sheet (in the form shown in FIG. 12, the outer sheet 12S, In the form shown in FIGS. 13 and 14, since the hydrophilizing agent 20 is applied only to the inner sheet 12H), such alignment is easy.

  Furthermore, in the pants-type disposable diaper as shown in the figure, a structure in which the interior body 200 is attached to the inside of the exterior body 12 has become common, and sweat absorption / moisture absorption in the exterior body 12 has conventionally been a problem. Yes. Therefore, it is desirable to improve the water absorption of the present invention when forming the exterior body 12, but the portion overlapping with the interior body 200 is covered with the interior body 200, so even if the hydrophilizing agent 20 is applied, it absorbs sweat and absorbs moisture. Can hardly be expected, and when the interior body 200 is fixed to the exterior body 12 with an adhesive, the adhesion may be insufficient due to the influence of the hydrophilizing agent 20. Therefore, as shown in FIGS. 12 and 14, the hydrophilizing agent 20 may be intermittently applied in the line flow direction so that the hydrophilizing agent 20 is not applied to the fixing region of the inner body 200 in the outer package 12. desirable. Of course, as shown in FIG. 13, the hydrophilizing agent 20 can be applied continuously in the line flow direction, and the hydrophilizing agent 20 can also be applied to the fixing region of the interior body 200 in the exterior body 12.

<Others>
Although the said example is an application example to a pants type disposable diaper, this invention is applicable also to a tape type disposable diaper and a sanitary napkin. For example, the application part of the hydrophilizing agent 20 in the above example is an area Z from the waist lower part U to the waist part of the intermediate part L, but widely used for other fit elastic parts, for example, absorbent articles in general. It has been is standing gathers, or may be applied to tape type disposable diaper of the dorsal portion of the body peripheral Ri portion and fastening a hydrophilizing agent 20 tape as target. Moreover, as long as it is the laminated part of a sheet | seat, it can apply also when applying the hydrophilizing agent 20 to the site | part which is not a stretchable part for a fit (namely, it is not necessary to have an elastic elastic member between sheets). Therefore, for example, one of the first sheet and the second sheet of the present invention can be the top sheet 30 and the other can be the intermediate sheet 40.

  Furthermore, in the present invention, as long as the water absorption is improved in the laminated portion of the first sheet and the second sheet, one or more other sheets may be laminated on either one or both sides of the front and back. In that case, the water absorption of the other sheet may be improved.

Apply 0.8 wt% (dry weight of sheet) of the hydrophilizing agent Silactol PHP 26 made by Schill Seilacher to one side of a water-repellent spunbond nonwoven fabric with a basis weight of 18 g / m ² , and apply the hydrophilizing agent to the coated surface. A spunbond nonwoven fabric (hereinafter simply referred to as a spunbond nonwoven fabric) having a basis weight of 13 g / m ^{2 and} a water repellent SMMS nonwoven fabric (hereinafter simply referred to as a SMMS nonwoven fabric) layered thereon and a hydrophilic agent applied thereon is placed on a horizontal table with the bottom side By placing various weights on these overlapping parts of the nonwoven fabric or not placing any weights at all, pressures of 0 kg / m ² , 50 kg / m ² , 100 kg / m ² , 300 kg / m ² , 500 kg / m ² Hold the pressurized state, lift the weight every time a predetermined time has passed, and drop water on the weight placement part on the upper surface of the SMMS nonwoven fabric (the surface opposite to the side facing the spunbond nonwoven fabric) It was confirmed whether or not water droplets penetrated into the SMMS nonwoven fabric within 15 minutes.

When the pressure is 300 kg / m ² , 6 hours, 10 hours, 26 hours, 30 hours, 34 hours, 50 hours, and 55 hours have elapsed since the start of pressurization (0 hours). Water droplet permeation was confirmed at the time. Further, when the pressurized state of the pressure ^{0kg / m 2, 50kg / m} 2, 100kg / m 2, 500kg / m 2 , the pressure before the start (0 hours), 7 hours from the start pressure, 22 hours, 46 hours Water droplet permeation was confirmed after 53 hours. The results are shown in Tables 1 and 2.

As can be seen from Tables 1 and ² , in the pressurized state of 0 to 100 kg / m ² , water droplets did not penetrate into the SMMS nonwoven fabric within 15 minutes even after 53 hours. On the other hand, in the pressurized state of 300 kg / m ² and 500 kg / m ² , water droplets did not penetrate into the SMMS nonwoven fabric within 15 minutes before the start of pressurization, but 300 kg / m ² In the pressurized state, water droplets permeated into the SMMS nonwoven fabric within 15 minutes at each time point after 6 hours had elapsed and at 500 kg / m ² after 7 hours had elapsed. From this result, it was confirmed that even if the water-repellent nonwoven fabric is not coated with a hydrophilizing agent, the water absorption is improved by repeatedly pressing the nonwoven fabric coated with the hydrophilizing agent.

Even when the pressure was 0 to 100 kg / m ² , it penetrated into the SMMS nonwoven fabric when it was on standby for more than 15 minutes after placing a water droplet. However, the time required for the permeation was shorter as the pressurization pressure was higher and the pressurization time was longer. From this, it was also confirmed that the water absorption is improved not only when held in a pressurized state.

  The present invention is suitable for a pants-type disposable diaper as in the above example, but can also be applied to a tape-type disposable diaper, a sanitary napkin, an absorbent pad, and the like.

  DESCRIPTION OF SYMBOLS 11 ... Liquid impervious sheet, 12 ... Exterior body, 12H ... Inner sheet, 12S ... Outer sheet, 12r ... Folded part, 200 ... Interior body, 30 ... Surface sheet, 40 ... Intermediate sheet, 50 ... Absorbing element, 56 ... Absorber, 58 ... packaging sheet, 60 ... side three-dimensional gather, 62 ... gather sheet, LB ... leg opening part (separation part), 20 ... hydrophilizing agent, W ... waist edge, U ... waist lower part , L: intermediate part, T: waist part, 12C: hydrophilizing agent coating apparatus.

Claims (4)

Absorbent article comprising a laminated portion formed by laminating a second sheet made of hydrophobic or water-repellent fibers so as to come into contact with either the front or back side of the first sheet made of hydrophobic or water-repellent fibers A method for improving water absorption in
The laminated part is a stretchable part for fitting formed by fixing an elongated elastic stretchable member between the first sheet and the second sheet with an adhesive in a stretched state,
By laminating a second sheet not coated with a hydrophilizing agent on the first sheet coated with a hydrophilizing agent, the laminated portion is formed ,
When applying the hydrophilizing agent to the first sheet, the hydrophilizing agent is not applied to the portion through which the elongated elastic elastic member passes and the first sheet and the second sheet are laminated. In addition, the elongated elastic elastic member is fixed to the portion where the hydrophilic agent is not applied with an adhesive in an elongated state,
After you mow, held in a pressurized state for 6 hours or longer under a pressure 300 kg / m ² or more at least the stacked portion in a thickness direction,
The water absorption improvement method in the absorbent article characterized by the above-mentioned. Absorbent article comprising a laminated portion formed by laminating a second sheet made of hydrophobic or water-repellent fibers so as to come into contact with either the front or back side of the first sheet made of hydrophobic or water-repellent fibers A method for improving water absorption in
The absorbent article has an absorbent body interposed between a liquid-permeable surface sheet and a liquid-impermeable sheet, and is formed so as to cover from the back side through the crotch to the abdomen, A pants-type disposable diaper that includes an exterior body that is attached to at least front and rear waist edges on the outer surface of the interior body and that covers at least the waist.
By laminating the second sheet not coated with the hydrophilizing agent on the first sheet coated with the hydrophilizing agent, the exterior body having the laminated portion is formed, and at that time, the first sheet Application of the hydrophilizing agent to the sheet is not performed on the fixing region of the inner body in the outer body,
Thereafter, at least the laminated part is held in a state of being pressurized in the thickness direction at a pressure of 300 kg / m ² or more for 6 hours or more .
The water absorption improvement method in the absorbent article characterized by the above-mentioned .   The method for improving water absorption in an absorbent article according to claim 1 or 2, wherein the product produced by applying the hydrophilizing agent is held in the pressurized state by being packed in a product package bag. The at least one of the first sheet and the second sheet is a sheet exposed on an inner surface or an outer surface, and the hydrophilizing agent is applied only to a second sheet side surface of the first sheet. water improvement method in the absorbent article according to any one of 1 to 3.

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