JP4827889B2 - Disposable diapers - Google Patents

Description

  The present invention particularly relates to improvement of a nonwoven fabric as a material in an absorbent article such as disposable disposable diapers and sanitary napkins that require good touch.

Nonwoven fabrics are widely used for disposable absorbent articles because they are excellent in porosity, bulkiness, absorbability, water permeability (liquid permeability), and the like, and can change their necessary characteristics. In recent years, in addition to a single-layer nonwoven fabric, a laminated nonwoven fabric body in which two or more layers are laminated to obtain desired properties has been used.
JP 2001-355173 A JP 2000-328420 A JP 11-290381 A JP-A-11-293554 JP 2000-051268 A

However, conventional laminated nonwoven fabrics, for example, SMS, SMMS, SSMMS (S means a nonwoven fabric layer by a spunbond method, M means a nonwoven fabric layer by a melt blown method) are hard and give a rough feel because of high friction. For this reason, it is not always satisfactory for use as a material for absorbent articles that require a good feel even to sensitive wearers. Further, where uniform smoothness and softness are required over the entire surface, it is not always satisfactory, and improvements have been desired.
Then, the main subject of this invention is providing the paper diaper which is rich in a softness | flexibility, has uniform and favorable smoothness and softness over the whole surface, and exhibits the outstanding tactile sense.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
A liquid-permeable top sheet, a liquid-impervious sheet substantially impermeable to liquid, an absorbent element interposed between these sheets, an outer sheet provided on the back side of the liquid-impervious sheet, A standing seat that forms a standing cuff for the leg circumference protruding to the use surface side,
A paper diaper using a nonwoven fabric laminate for at least one of the top sheet, the outer sheet and the upright sheet,
The nonwoven fabric laminate is obtained by extruding an extrusion raw material mixed with a softening agent in a raw material stage before melt extrusion, at least one first spunbond nonwoven fabric layer formed with a web by a spunbond method, and a softener not mixed. The first and second spunbonds include at least one or more second spunbond nonwoven layers formed of a web by a spunbond method and at least one meltblown nonwoven layers of a web formed by a meltblown method. In a state where a meltblown nonwoven fabric layer is interposed between the nonwoven fabric layers, they are laminated,
The nonwoven laminate is adhered by a hot-melt adhesive to another sheet other than its own in the paper diaper, the nonwoven layer of the adhesive side of the nonwoven fabric laminate, a second spunbond nonwoven fabric layer, wherein the softening agent is not mixed It is said that
A paper diaper having a nonwoven fabric characterized by the above.

(Function and effect)
The spunbond nonwoven fabric (S) is a continuous filament, has no fuzz and is excellent in the touch and is suitable for giving smoothness. The meltblown nonwoven fabric (M) is a discontinuous fiber and is suitable for imparting flexibility. However, as described above, even in the case of these laminated nonwoven fabrics, the material of the absorbent article is required to have a good touch even for sensitive wearers because it is hard and has a rough feel due to high friction. It was not always satisfactory to use as. Further, uniform smoothness and softness are required over the entire surface, but this is not always satisfactory, and an improvement is desired.

From the viewpoint of imparting flexibility, it may be possible to improve by applying or impregnating a softening agent to the entire surface of the laminated nonwoven fabric body or by impregnation. If it is not applied and applied excessively, it will give an excessive “slimming” feeling, making it difficult to balance flexibility and smoothness. Moreover, when manufacturing absorbent articles, the nonwoven fabric is usually assembled by bonding with a hot-melt adhesive, but it has been found that the adhesive strength of the hot-melt adhesive is reduced due to the presence of the softening agent. In particular, in order to form a standing cuff using an elastic elastic member such as thread rubber, when the nonwoven fabric is used as a standing sheet and the nonwoven fabric and the elastic elastic member or the opposing nonwoven fabric are to be bonded, It has been found that due to the decrease in adhesive strength due to the presence, the elastic stretchable member cannot be fixed to a predetermined portion, and the elastic stretchable member disposed at the predetermined portion is drawn. Furthermore, it was also found that unevenness in flexibility occurs due to uneven distribution of the softener in the surface direction.

However, in the present invention, when obtaining a spunbond nonwoven fabric layer having a web formed by the spunbond method, the softener is mixed in the raw material stage before melt extrusion. The bond non-woven fabric layer is uniformly exerted over the entire surface and has a high flexibility, as well as uniform and good smoothness and softness over the entire surface, and exhibits an excellent tactile sensation. Secondly, the modification of only the surface layer is sufficient, and it is easy to balance flexibility and smoothness without giving an excessive “slimming” feeling. Third, in the case of manufacturing an absorbent article, when the nonwoven fabric laminate is bonded to another sheet with a hot melt adhesive, the nonwoven fabric layer on the side to be bonded is not mixed with a softening agent. The said nonwoven fabric laminated body and an elastic elastic member or the nonwoven fabric which opposes can be adhere | attached reliably.

<Invention of Claim 2>
The standing cuff has a fixed portion fixed to the paper diaper and a free portion protruding from the fixed portion, and the free portion is formed by double the standing sheet and elastic around the leg therebetween. It has a structure in which an elastic member is sandwiched and bonded with a hot melt adhesive,
The nonwoven fabric laminate is used for the standing sheet, and the double standing sheets forming the free portion are both in the second span where the nonwoven fabric layer on the bonding side by the hot melt adhesive is not mixed with the softening agent. The paper diaper according to claim 1, wherein the nonwoven fabric layer which is a bonded nonwoven fabric layer and forms an outer surface is the first spunbond nonwoven fabric layer mixed with the softening agent .

<Invention of Claim 3>
The liquid-impervious sheet or the outer surface sheet extends on the back side of the standing sheet at the fixed portion of the standing cuff,
Between the standing sheet and the liquid-impervious sheet or the outer sheet on the back surface thereof in the fixed portion of the standing cuff, an elastic elastic member for a leg gathering plane gathering is sandwiched therebetween and bonded by a hot melt adhesive. And
The standing sheet in the fixed portion of the standing cuff is a nonwoven fabric layer that is used as a second spunbond nonwoven fabric layer in which the nonwoven fabric layer on the bonding side by the hot melt adhesive is not mixed with the softening agent. The first spunbond nonwoven fabric layer is mixed with the softener,
The disposable diaper according to claim 2.

<Invention of Claim 4>
The disposable diaper according to any one of claims 1 to 3, wherein the amount of the softening agent mixed in the nonwoven fabric laminate is 0.5 to 3.0 mass%.

(Function and effect)
If the amount of the softening agent is small, the modification of the softness and smoothness is not sufficient. If the amount is excessive, an excessive “slimming” feeling is given, and further, the adhesive strength of the hot melt adhesive is lowered.

  As described above, according to the present invention, it is rich in flexibility, has uniform and good smoothness and softness over the entire surface, and exhibits excellent tactile sensation.

The present invention will be described in detail below.
<Nonwoven fabric and laminates thereof>
The present invention relates to a disposable diaper, which will be described later, a nonwoven fabric laminate in which two or more layers of a spunbond nonwoven fabric (S) layer having a web formed by a spunbond method and a meltblown nonwoven fabric layer (M) having a web formed by a meltblown method are laminated. Used as at least one of the top sheet 1, the outer sheet 10, and the upright sheet 4. Therefore, first, the spunbonded nonwoven fabric of the present invention will be described, and then a form example of a disposable diaper will be described.

  In the production of the spunbonded nonwoven fabric of the present invention, for example, the raw material polymer is melted with an extruder or the like and discharged from a spinning reel having a spinning nozzle to spin long fibers. The spun filaments are cooled by a cooling fluid, and further, tension is applied to the long fibers with drawn air to a predetermined fineness. The filaments are collected on the collection belt as they are and deposited to a predetermined thickness, and then bonded. . In this case, in addition to heat-sealing the filaments with the heat of the filament itself, other bonding methods such as a needle punch method, a water jet (spun lace method), a method of entanglement treatment by means such as ultrasonic sealing, or It can be bonded according to a method such as a heat fusion method (calendar method or air-through method) using a hot embossing roll.

  The spunbond nonwoven fabric may be a core-sheath type composite fiber as a fiber material. In this case, a polymer such as an ethylene-based polymer constituting the core and a polymer such as a crystalline propylene-based polymer constituting the sheath are used. Each of the melts is melted separately by an extruder or the like, and each melt is discharged from a spinning reel having a composite spinning nozzle configured to form a desired core-sheath structure and discharged. Spin the fiber. The treatment after spinning may be the same as described above. The fineness of the core-sheath type composite fiber is 5d or less, and preferably 3d or less in that a nonwoven fabric with more flexibility can be obtained. Here, the core-sheath type composite fiber is a concentric type in which a circular core part is wrapped in a donut-shaped sheath part having the same core in the fiber cross section, and the core part and the core part are displaced from each other. An eccentric type in which the part is wrapped in the sheath part, or a parallel type form in which the eccentric core part is not wrapped in the sheath part.

  On the other hand, conventionally known methods can be employed for the production of the melt blown nonwoven fabric of the present invention. For example, a raw material polymer such as crystalline propylene is melt-extruded, fibers spun from a melt-blow spinneret are blow-spun as an ultra-fine fiber stream with a high-temperature and high-speed gas, and an ultra-fine fiber web is collected on a collection device such as a wire mesh or belt And can be manufactured through the above-described bonding step. The average fiber diameter of the fibers forming this melt blown nonwoven fabric is usually about 1 to 30 μm, preferably about 2 to 10 μm.

The basis weight of the nonwoven fabric of the present invention is usually 3 to 100 g / m ² , preferably 7 to 30 g / m ² for the spunbonded nonwoven fabric. Moreover, about a melt blown nonwoven fabric, it is 1-50 g / m < ² > normally, Preferably it is 3-30 g / m < ² >. The basis weight may be appropriately determined according to the application.

The nonwoven fabric laminate in the present invention is a laminate of a spunbond nonwoven fabric (S) and a meltblown nonwoven fabric (M), and is a spunbond nonwoven fabric layer / meltblown nonwoven fabric layer that is an S layer composed of at least one pair of spunbond nonwoven fabrics. A nonwoven fabric laminate having an SM structure exhibits excellent flexibility. Moreover, the laminated body which has a structure in which the layer of a spunbond nonwoven fabric (S) exists in the both sides of the layer of at least 1 melt blown nonwoven fabric (M) may be sufficient. The basis weight of the nonwoven fabric laminate is usually 7 to 100 g / m ² , preferably 10 to 70 g / m ² . More preferably, it is 10-50 g / m < ² >.

  When obtaining a laminate, any method can be used as long as it is a method capable of laminating a spunbond nonwoven fabric and a meltblown nonwoven fabric and integrating the two to form a laminate, and is not particularly limited. For example, fibers formed by the melt blown method are directly deposited on a spunbond nonwoven fabric to form a meltblown nonwoven fabric, and then the spunbond nonwoven fabric and the meltblown nonwoven fabric are heat-sealed. A method of fusing both nonwoven fabrics by heating and pressurization, a method of bonding a spunbond nonwoven fabric and a melt blown nonwoven fabric with an adhesive such as a hot melt adhesive or a solvent-based adhesive can be employed.

  A method of directly forming a meltblown nonwoven fabric on a spunbond nonwoven fabric can be performed by a meltblown method in which a melt of a thermoplastic resin is sprayed on the surface of the spunbond nonwoven fabric to deposit fibers. At this time, the spunbonded nonwoven fabric and the meltblown nonwoven fabric are simultaneously sprayed and deposited on the spunbonded nonwoven fabric by applying a negative pressure to the surface opposite to the surface on which the melt is sprayed and spraying the fibers formed by the meltblown method. Are integrated to obtain a flexible nonwoven fabric laminate having a spunbond nonwoven fabric layer and a meltblown nonwoven fabric layer. When integration of both nonwoven fabrics is inadequate, it can fully integrate with a heating-pressing embossing roll etc.

  As a method of fusing a spunbond nonwoven fabric and a meltblown nonwoven fabric by heat fusion, a method of heat-sealing the entire contact surface between the spunbond nonwoven fabric and the meltblown nonwoven fabric, a contact surface between the spunpond nonwoven fabric and the meltblown nonwoven fabric is used. There is a method of heat-sealing a part.

<About softener>
In this invention, the use surface which touches at least skin of a laminated body consists of a spun bond nonwoven fabric layer. In forming the spunbonded nonwoven fabric (S) layer, a softening agent is uniformly mixed in a raw material stage before melt extrusion, for example, a pellet manufacturing stage. This extruded raw material is melted in an extruder as described above, and a web is formed by a spunbond method. In the case of the SSMMS structure, a softening agent can be mixed in each SS layer on one side. It is desirable that no softener is mixed into the meltblown nonwoven fabric layer.

In the present invention, the spunbond nonwoven fabric layer mixed with the softening agent is placed on the outer surface of the absorbent article for use, but the nonwoven fabric laminate is bonded to another sheet with a hot melt adhesive. The non-woven fabric layer is not mixed.

  Here, it is desirable that the amount of the softener mixed in the nonwoven fabric laminate is 0.5 to 3.0% by mass. In the present invention, the “mixing amount of the softening agent into the nonwoven fabric laminate” means that the softening agent is mixed only in the spunbond nonwoven fabric (S) layer on one side, and the softener is added to the spunbond nonwoven fabric (S) layer on both sides. Each may be mixed, but in any case, it means the total amount of mixing.

As the softening agent, for example, a wax emulsion, a reactive softening agent, a silicone-based one, and the like can be used, but it is preferable to use a surfactant. As surfactants, carboxylate anionic surfactants, sulfonate anionic surfactants, sulfate ester anionic surfactants, phosphate ester anionic surfactants (especially alkyl phosphates). Acid ester salts) and other anionic surfactants;
Sorbitan fatty acid ester, diethylene glycol monostearate, diethylene glycol monooleate, glyceryl monostearate, glyceryl monooleate, polyhydric alcohol mono fatty acid ester such as propylene glycol monostearate, N- (3-oleyloxy-2-hydroxypropyl) diethanolamine , Polyoxyethylene hydrogenated castor oil, polyoxyethylene sorbit beeswax, polyoxyethylene sorbitan sesquistearate, polyoxyethylene monooleate, polyoxyethylene sorbitan sesquistearate, polyoxyethylene glyceryl monooleate, polyoxyethylene monostearate Rate, polyoxyethylene monolaurate, polyoxyethylene monooleate, polyoxyethylene cetyl acetate Le, polyoxyethylene lauryl ether, nonionic surfactants;
Cationic surfactants such as quaternary ammonium salts, amine salts or amines;
A zwitterionic surfactant such as an aliphatic derivative of a secondary or tertiary amine containing carboxy, sulfonate, sulfate, or an aliphatic derivative of a heterocyclic secondary or tertiary amine;
Etc. can be used.
Moreover, a well-known chemical | medical agent can be added to the softening agent of this invention as a secondary additive (small component) as needed. As an example, saccharides such as sorbitol or glucose or a mixture thereof, flavoring agents, coloring agents, preservatives, antioxidants, and other secondary additives can be added.

  The nonwoven fabric raw material itself can be the same as the conventional nonwoven fabric, and for example, one or several kinds of cotton, rayon, polyester, polypropylene, nylon, acrylic, vinylon, glass fiber, etc. are appropriately selected. Can be used.

By the way, the nonwoven fabric according to the present invention is more preferable in terms of smoothness and softness when the basic characteristics by the KES system (Kawabata Evaluation System) are the following conditions.
1) Surface characteristics: mean friction coefficient (MIU) and mean deviation of friction coefficient (MMD)
For this surface property test, “Friction Tester KESSE” manufactured by Kato Tech Co., Ltd. can be used. At the time of measurement, as shown in FIG. 1, a friction element consisting of a piano wire having a cross-sectional diameter of 0.5 mm and a contact surface length of 5.0 mm is brought into contact with the nonwoven fabric sample with a contact pressure of 10 g. The friction coefficient is measured when the nonwoven fabric sample is moved 2 cm at a speed of 0.1 cm / sec while applying a tension of 20 g / cm to the moving direction.
The average friction coefficient (MIU) is preferably 0.01 to 1.40 for MD (Machine Direction) and 0.01 to 1.50 for CD (Cross Direction). This is because the nonwoven fabric has good smoothness.
Moreover, as for the average deviation (MMD) of a friction coefficient, it is preferable that MD is 0.01-1.0 and CD is 0.01-1.30. This is because a non-woven fabric with improved smoothness can be obtained by suppressing variations in smoothness. The average deviation (MMD) of the friction coefficient is a variation of the surface thickness when the friction element is moved, that is, a value obtained by dividing the friction coefficient by the friction distance (movement distance = 2 cm).

2) Bending properties: bending stiffness (B) and hysteresis (2HB)
In this bending characteristic test, an automated pure bending tester KESFB2-AUTO-A manufactured by Kato Tech Co., Ltd. was used. As shown in FIG. Curvature and bending when bending to the maximum side of curvature 2.5cm ^-1 by the pure bending that always keeps the arc and then returning to the original, then bending back to the maximum curvature of -2.5cm ^-1 and then returning to the original This is to evaluate the relationship with the moment.
This relationship is obtained as a value on the hysteresis curve shown in FIG. 3, and the bending stiffness (B) of the nonwoven fabric expressed by the average inclination between the curvatures of 0.5 to 1.5 cm ⁻¹ is MD (Machine Direction). It is preferable that it is 0.001-0.004 g * cm < ² > / cm and CD (Cross Direction) is 0.001-0.020 g * cm < ² > / cm. This is because a non-woven fabric with low bending resistance is used.
Further, the bending recovery property (2HB) of the nonwoven fabric expressed by the average hysteresis width of the bending moment M between the curvatures of 0.5 and 1.5 cm ⁻¹ is MD of 0.001 to 0.002 g · cm / cm, CD Is preferably 0.001 to 0.010 g · cm / cm. This means that the greater the bend recovery (2HB), the worse (lower) the bend recovery is. If it is in the above range, the nonwoven fabric has an appropriate bend recovery.
The above four measured values of [1] average friction coefficient (MIU), [2] average deviation of friction coefficient (MMD), [3] bending stiffness (B), and [4] hysteresis width (2HB) are within a predetermined range. Thus, a non-woven fabric having good smoothness and softness is completed.
The surface characteristics can be adjusted mainly by adjusting the mixing amount of the softening agent. Further, the bending characteristics can be adjusted by adjusting the basis weight of the M layer.

<Examples of disposable paper diapers>
Next, an example of a disposable paper diaper will be described with reference to the accompanying drawings. That is, this example has a fastening piece attached to both ends of the back side of the paper diaper, has a hook element on the fastening surface of the fastening piece, and the outer sheet constituting the back side of the paper diaper is a non-woven fabric. The disposable diaper is a disposable diaper in which a hook element of the fastening piece can be engaged with an arbitrary portion of the surface of the nonwoven fabric outer sheet.

A specific example will be described with reference to FIGS. 4 and 5. In the illustrated paper diaper, the liquid-permeable top sheet 1 made of a nonwoven fabric or the like and a liquid-impervious sheet that does not substantially transmit liquid, such as polyethylene, are used. Between the liquid-impervious sheet 2 that does not allow the liquid to completely pass therethrough, an absorbent body 3 made of cotton-like pulp or the like, for example, rectangular or preferably has an hourglass shape with a certain degree of rigidity as shown in the figure, is interposed. The absorbent body 3 can be covered with upper and lower tissue papers for absorption, and constitutes an absorbent element.
The liquid-impermeable sheet 2 has a rectangular shape wider than the absorbent element, and an outer surface sheet 10 made of an hourglass-shaped nonwoven fabric or the like is provided on the outer side thereof.
The liquid-permeable top sheet 1 has a rectangular shape wider than the absorbent element, extends slightly outward from the side edge of the absorbent element, and is fixed to the liquid-impermeable sheet 2 by a hot melt adhesive or the like. The fixed portion related to the present invention including the portion is indicated by a symbol *).

On both sides of the disposable diaper, a leg-standing standing cuff B protruding toward the use surface is formed. The standing cuff B is a standing sheet 4 made of a breathable nonwoven fabric or the like substantially continuous in the width direction, and elastically stretchable. It is comprised by the member, for example, the elastic elastic member 5 for the leg periphery as shown in figure or one made of thread rubber. 7 is a fastening piece by a hook-and-loop fastener.
Further, the standing cuff B is formed in a double form by folding the standing sheet 4 inwardly with a short inner surface side, and wraps the leg elastic elastic members 5 with a hot melt adhesive or the like.

The inner surface of the double upright sheet 4 has a fixing start end at a position separated from the side edge of the liquid-permeable top sheet 1, and extends outward in the width direction from the fixing start end to the extending edge of the liquid-impermeable sheet 2. The part is fixed by a hot melt adhesive or the like. The outer surface of the double upright sheet is fixed to the outer surface sheet 10 by a hot melt adhesive or the like on the lower surface.
As a result, the starting end of the double standing sheet 4 that is fixed to the liquid-impermeable sheet 2 forms the standing end of the standing cuff B. Around the leg, the inside of the standing end is a free part that is not fixed to the product body, and it functions as a standing part that goes to the center of the product and a flat contact part that turns back halfway and goes outward. And conceptually divided.

On the other hand, although not shown, at the front and rear ends in the longitudinal direction, the portion corresponding to the raised portion (extension portion of the raised portion) is directed to the product in a state toward the center side of the product, specifically through the hot melt adhesive or the like. It is fixed to the outer surface of the liquid top sheet 1 and the liquid-impermeable sheet 2, and is fixed on the upright portion equivalent portion in a state where the portion corresponding to the plane contact portion (extension portion of the plane contact portion) is turned upside down.
The elastic stretchable member 5 has a basic form in which at least one elastic stretch member 5 is at the flat contact portion. In particular, the elastic stretchable member 5 is preferably at the front end portion of the flat contact portion, and is also elastic at the standing portion. It is preferable to have the elastic member 5.

  The optimum form is that it is in the vicinity of the standing end, in the vicinity of the turn-up, and at the tip of the flat contact portion. It is further desirable to have a plurality of tips at the tip of the flat contact portion as shown in the figure. In order to increase the standing force, the elastic members 5 and 5 can be further provided on the standing portion. In the illustrated form, there are six in total.

  In this example, by using a hook-and-loop fastener as the fastening piece 7, the fastening piece 7 can be mechanically fixed to the outer sheet 10 made of a nonwoven fabric. Therefore, a so-called target tape can be omitted, and the fastening position by the fastening piece 7 can be freely selected.

  The fastening piece 7 has a base of a fastening base material such as plastic, polylaminated nonwoven fabric, or paper joined to the outer surface sheet 10 with an adhesive, for example, and has a hook element 7A on the tip side. The hook element 7A is bonded to the fastening substrate with an adhesive. The hook element 7A has a large number of engaging pieces on the outer surface side thereof. A temporary fixing adhesive portion 7B is provided on the tip side from the hook element 7A. At the end of the assembly of the product, the temporary fixing adhesive portion 7B is adhered to the upright sheet 4 so as to prevent the fastening piece 7 from being peeled off at the front end side. At the time of use, it peels off against the adhesive force and brings the front end of the fastening piece 7 to the front body. The fastening base material is exposed at the tip side of the temporary fixing adhesive portion 7B, and is a tab portion.

  Now, as shown in FIG. 4, a target print sheet 20 as a design sheet is provided on the inner surface side of the outer sheet 10 on the opening side of the front body, and the hook element 7 </ b> A of the fastening piece 7 is fastened. Target printing is applied with a design that serves as a guide for the position to be performed, and is provided so as to be visible through the outer sheet 10 from the outside.

  When the disposable diaper is mounted, the disposable diaper is mounted on the body in the shape of a boat, and the contraction force of the elastic elastic members 5, 5... Acts, as shown in FIG. The standing cuff B is raised by the contraction force 5.

  The space surrounded by the standing part forms a confined space for urine or soft stool. When urinating into this space, the urine passes through the liquid-permeable top sheet 1 and is absorbed into the absorbent body 3, and the solid part of loose stool becomes a barrier at the standing part of the standing cuff B, which is overcome. Is prevented. In the unlikely event that urine leaks laterally over the standing distal side edge of the standing part, side leakage is prevented by the stop function by the flat contact part.

In this embodiment, it is desirable that the standing sheet 4 forming each standing cuff B is not liquid-permeable but substantially liquid-impervious (may be semi-liquid-permeable). Further, the liquid-permeable sheet (for example, non-woven fabric) that forms the upright sheet 4 may be repelled by silicon treatment or the like. In any case, it is preferable that the standing sheet 4 and the outer sheet 10 are air permeable, and the standing sheet 4 and the outer sheet 10 are each a sheet having a water pressure resistance of 100 mmH ₂ O or more, particularly a nonwoven fabric. . As a result, as shown in FIGS. 4 and 5, air permeability is exhibited at the side in the width direction of the product, and wearer's stuffiness can be prevented.

  In particular, by using a non-woven fabric, it is possible to obtain a disposable paper diaper that produces almost no sound during wearing and gives a cloth-like feel. Non-woven material fibers constituting the outer sheet 10, the liquid-permeable top sheet 1 and the upright sheet 4 are made of olefin-based, polyester-based, amide-based synthetic fibers such as polyethylene or polypropylene, and rayon, cupra, etc. Natural fibers such as fibers and cotton can be used, and nonwoven fabrics obtained by an appropriate processing method such as a spun bond method, a thermal bond method, a melt blow method, a needle punch method, or the like can be used.

  And in the said form example, the liquid-permeable top sheet 1, the standing sheet 4, and the outer surface sheet 10 are sheets which comprise the outer surface of an absorbent article. Therefore, the nonwoven fabric laminated body which concerns on this invention is employ | adopted as these sheet materials. In particular, it is desirable to employ the nonwoven fabric laminate according to the present invention on the use surface (upper surface in FIG. 5) that is in direct contact with the skin.

On the other hand, the nonwoven fabric laminate of the present invention, when wrapped resilient and elastic members, or even when interposed between the other sheet, gives good properties. That is, for example, in a form in which a standing cuff ( three-dimensional gather ) is formed by wrapping a standing sheet 4 by fixing a single elastic elastic member 5 made of thread rubber or a plurality of elastic members 5 around the legs with a hot melt adhesive as shown in the figure. , when using the nonwoven fabric laminate of the present invention as a sheet for forming the standing sheet 4 is one example. In another example, as shown in a modification example of the flap on the right side of FIG. 5, an elastic elastic member 5 </ b> A for leg gathering plane gathers is interposed between the upright sheet 4 and the outer sheet 10 and fixed with a hot melt adhesive. Te in the form that constitutes the plane gathers are examples of other when using the nonwoven fabric laminate of the present invention as a sheet for forming the standing sheet 4 and or the outer sheet 10. Yet another example is configuring the planar gather fixed by a hot-melt adhesive with intervening resilient and elastic members 5B for Ashimawari plane gathers between the liquid-impermeable sheet 2 extend the standing sheet 4 in embodiments, it is another example may use nonwoven laminate according to the present invention as a sheet for forming the standing sheet 4.
The above is an example of a tape type, but the description is intentionally omitted, but the nonwoven fabric laminate according to the present invention can be used with the same idea even in the case of a pants-type paper diaper. It can also be used for other absorbent articles such as sanitary napkins.

The effects of the present invention will be described below based on examples.
<Relationship between softener mixing amount and adhesiveness>
The nonwoven fabric laminate according to the present invention, used as a sheet material for forming the standing sheet 4 of the disposable diapers of the embodiment described above, the standing sheet and adhesion to the other sheet (N) and the standing sheet The test was conducted with respect to the pull-in length (cm) of the rubber thread provided in.

The test regarding the adhesive strength was performed in a dry state and a wet state. There were three types of upright sheets: no softener (conventional product), 1.0% softener (Example 1), and 1.5% softener (Example 2). Another sheet used was as shown in Table 1, which is an air-through nonwoven fabric, and spunbonded nonwoven fabric. The application amount of the hot melt adhesive used for adhering the standing sheet and the other sheet was the same, and the application amount used for the conventional product was used.

The test on the pull-in length of the rubber thread was conducted by applying a disposable diaper to the tip and the base of each standing sheet (ie, the tip side and the base side in the standing cuff B) by applying a temperature of 40 ° C. and a humidity of 70% with a thermo-hygrostat. By measuring the pull-in length of the rubber thread (located in The results are shown in Table 1.

  As can be seen from Table 1, the non-woven fabric increases in smoothness but increases in adhesive strength when the amount of the softening agent increases. And although not shown in Table 1, what produced 3.2% of a softening agent was also produced, but it has been proved that it has almost no adhesiveness and cannot withstand practical use.

<Test for KES value>
The correspondence with the sensory evaluation of 100 adults was examined while repeating the test on the surface characteristics and the bending characteristics and taking four data. The results of sensory evaluation are shown in Table 2 together with the results of KES evaluation. In addition, all the comparative examples show the current commercial products. In Example 3, 1% of a softening agent was mixed in both S layers (therefore, 0.5% for each layer) in the commercial product of Comparative Example 1 (a non-woven fabric having an SMS structure was used for the upright sheet). Other examples are the same.

  In Table 2, the evaluation of “smoothness” and “softness” is based on five test evaluators. For “smoothness”, 2 points for smoothness, 1 point for slightly smoothness, 0 points for non-smoothness, 2 points for “softness”, 1 point for softness, 1 point for softness In addition, the total of five evaluation points is 0 to 4 points, x is 5 to 7 points, and 8 to 10 points is o. From Table 2, it can be seen that a nonwoven fabric having a good “smoothness” and “softness” feeling can be obtained by controlling the basic characteristics of the KES system.

On the other hand, Table 3 shows the results of examining the surface characteristics and bending characteristics in the same manner by changing the structure of the nonwoven fabric laminate and the amount of the softener mixed therein. Note that the basis weight of each nonwoven fabric is 15 g / m ² .

It is explanatory drawing of the test method of a surface characteristic. It is explanatory drawing of the test method of a bending characteristic. It is a relationship figure of a bending characteristic. It is an expanded view of the tape-type paper diaper of this invention. It is a 4-4 arrow directional view of FIG. 4 shown with a modification.

  DESCRIPTION OF SYMBOLS 1 ... Liquid-permeable top sheet, 2 ... Liquid-impermeable sheet, 3 ... Absorber, 4 ... Standing sheet, 5 ... Elastic elastic member, 7 ... Fastening piece, 10 ... Outer surface sheet, 20 ... Target printing sheet.

Claims (4)

A liquid-permeable top sheet, a liquid-impervious sheet substantially impermeable to liquid, an absorbent element interposed between these sheets, an outer sheet provided on the back side of the liquid-impervious sheet, A standing seat that forms a standing cuff for the leg circumference protruding to the use surface side,
A paper diaper using a nonwoven fabric laminate for at least one of the top sheet, the outer sheet and the upright sheet,
The nonwoven fabric laminate is obtained by extruding an extrusion raw material mixed with a softening agent in a raw material stage before melt extrusion, at least one first spunbond nonwoven fabric layer formed with a web by a spunbond method, and a softener not mixed. The first and second spunbonds include at least one or more second spunbond nonwoven layers formed of a web by a spunbond method and at least one meltblown nonwoven layers of a web formed by a meltblown method. In a state where a meltblown nonwoven fabric layer is interposed between the nonwoven fabric layers, they are laminated,
The nonwoven laminate is adhered by a hot-melt adhesive to another sheet other than its own in the paper diaper, the nonwoven layer of the adhesive side of the nonwoven fabric laminate, a second spunbond nonwoven fabric layer, wherein the softening agent is not mixed It is said that
A paper diaper having a nonwoven fabric characterized by the above. The standing cuff has a fixed portion fixed to the paper diaper and a free portion protruding from the fixed portion, and the free portion is formed by double the standing sheet and elastic around the leg therebetween. It has a structure in which an elastic member is sandwiched and bonded with a hot melt adhesive,
The nonwoven fabric laminate is used for the standing sheet, and the double standing sheets forming the free portion are both in the second span where the nonwoven fabric layer on the bonding side by the hot melt adhesive is not mixed with the softening agent. The paper diaper according to claim 1, wherein the nonwoven fabric layer which is a bonded nonwoven fabric layer and forms an outer surface is the first spunbond nonwoven fabric layer mixed with the softening agent . The liquid-impervious sheet or the outer surface sheet extends on the back side of the standing sheet at the fixed portion of the standing cuff,
Between the standing sheet and the liquid-impervious sheet or the outer sheet on the back surface thereof in the fixed portion of the standing cuff, an elastic elastic member for a leg gathering plane gathering is sandwiched therebetween and bonded by a hot melt adhesive. And
The standing sheet in the fixed portion of the standing cuff is a nonwoven fabric layer that is used as a second spunbond nonwoven fabric layer in which the nonwoven fabric layer on the bonding side by the hot melt adhesive is not mixed with the softening agent. The first spunbond nonwoven fabric layer is mixed with the softener,
The disposable diaper according to claim 2.   The disposable diaper according to any one of claims 1 to 3, wherein the amount of the softening agent mixed in the nonwoven fabric laminate is 0.5 to 3.0 mass%.

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