RU2822183C1 - Disposable diaper and method for production thereof - Google Patents

Abstract

FIELD: hygiene.

SUBSTANCE: disposable diaper includes an upper sheet forming the surface of the side facing the user, a sheet not permeable to liquids and located on the side of the back surface, and an absorbent element located between them. Moisturizing agent, mainly containing glycerine, is applied to the top sheet, the wetting agent application zone is a zone exposed to exposure, which can be at least visually recognized directly from the side of the surface facing the user, when the product is unfolded, and the exposed zone has application zones Q with high concentration of a wetting agent in at least one of the peripheral parts in the forward-backward direction, and parts peripheral in direction of width, and application zone MZ with low concentration of wetting agent in zone intermediate between application zones with high concentration.

EFFECT: object is to provide a disposable diaper, which enables to confirm whether a skin care agent, in particular a moisturizing agent, is placed in an article during the manufacturing process or not, and a method of making a disposable diaper.

5 cl, 14 dwg

Description

Field of technology to which the invention relates

[0001]

The present invention relates to a disposable diaper and a method for its manufacture.

Prior Art

[0002]

A disposable diaper often causes roughness to the wearer's skin, particularly rashes, which is unfavorable.

Examples of the cause of this include friction against the skin while wearing a diaper and stimulation received by the skin from body fluids and discharge (urine and loose stool) due to wearing a diaper for a long time.

[0003]

In particular, the cause associated with the stimulant effect due to skin contact with liquid stool for a long time is significant. To suppress this, the diaper must allow liquid stool to be quickly absorbed into the absorbent component. If the diaper can quickly absorb liquid stool into the absorbent component, this is useful not only for reducing the stimulant effect perceived by the skin, but also for preventing leakage from the leg portion or dorsal portion.

[0004]

The first reason that liquid stool is prevented from being absorbed through the topsheet is that as liquid stool passes through the topsheet, a component of the liquid stool that cannot pass through the topsheet remains on a portion of the surface of the fibers forming the topsheet, and the topsheet becomes “clogged.” The second reason for preventing liquid stool from being absorbed through the top sheet is that the rate of bowel movements exceeds the absorption rate provided by the diaper and the liquid stool cannot be absorbed and remains on the top sheet.

Therefore, it is very important that the diaper ensures that liquid stool is quickly absorbed into the absorbent component.

[0005]

Patent Literature 1 discloses that a skin care agent, in particular a skin care agent containing a diamide derivative, is placed in the top sheet between so-called cuffs in the form of gathers on both sides of the diaper, defined in the width direction.

[0006]

Particularly in the case of a diaper worn by an infant, the infant's skin is sensitive and so-called diaper dermatitis easily occurs.

List of links

Patent literature

[0007]

Patent Literature 1: JP 2018-102836 A

The essence of the invention

Technical problem

[0008]

In the case of obtaining a diaper containing a skin care agent for suppressing diaper dermatitis, it is very important from a quality assurance point of view to confirm whether the skin care agent is included in the product during the manufacturing process of the product or not.

[0009]

Therefore, the main object of the present invention is to provide a disposable diaper capable of confirming whether a skin care agent, in particular a moisturizer, is included in the product during manufacturing or not, and a method for producing a disposable diaper.

Solution

[0010]

An example aspect of a disposable diaper that can solve the above problem is as follows.

<Exemplary aspect of a disposable diaper>

A disposable diaper including a top sheet forming a user-facing side surface, a liquid impermeable sheet located on the rear surface side, and an absorbent member located therebetween,

wherein a moisturizing agent containing mainly glycerin is applied to the top sheet,

the moisturizer application area is an exposed area that can be at least visually recognized directly from the user-facing surface when the product is unfolded, and

the exposed area has application zones with a high concentration of wetting agent in at least one of the portions peripheral in the front-to-back direction and portions peripheral in the width direction, and an application zone with a low concentration of wetting agent in a zone intermediate between high concentration application areas.

[0011]

An exemplary aspect of a method for making a disposable diaper is as follows.

<Exemplary Aspect of a Method for Making a Disposable Diaper>

A method for making a disposable diaper including a top sheet forming a user-facing side surface, a liquid-impervious sheet located on the rear surface side, and an absorbent member located therebetween, the method comprising:

applying a moisturizer containing mainly glycerin to the top sheet; And

confirming whether moisturizer has been applied or

No,

wherein the area of application of the moisturizer is an area exposed to action, which can be at least visually recognized directly from the side of the surface facing the user when the product is unfolded,

the exposed area has application zones with a high concentration of wetting agent in at least one of the portions peripheral in the front-to-back direction and portions peripheral in the width direction, and an application zone with a low concentration of wetting agent in a zone intermediate between high concentration application areas, and

upon confirmation, images of high concentration application areas are obtained using a near-infrared camera, and whether a moisturizer is present or not is confirmed based on the density level of the acquired image.

Preferred effects of the invention

[0012]

According to the present invention, it can be confirmed whether a skin care agent, in particular a moisturizer, is included in the product during manufacturing or not.

Brief description of drawings

[0013]

Fig. 1 is a plan view illustrating the inner surface of a pant-type disposable diaper in an unfolded state.

Fig. 2 is a plan view illustrating an outer surface of a pant-type disposable diaper in an unfolded state.

Fig. 3 is a sectional view taken along line 2-2 in FIG. 1.

Fig. 4 is a sectional view taken along line 3-3 in FIG. 1.

Fig. 5(a) is a sectional view taken along line 4-4 in FIG. 1, and fig. 5(b) is a sectional view taken along line 5-5 in FIG. 1.

Fig. 6 is a perspective view of a pant-type disposable diaper.

Fig. 7 is a plan view for describing an exposed area that can be visually recognized directly from the user-facing surface when the product is unfolded.

Fig. 8 is a plan view of an exemplary moisturizer application embodiment.

Fig. 9 is a plan view of another example of a moisturizer application embodiment.

Fig. 10 is a plan view of an example application area with a high concentration of moisturizer.

Fig. 11 is a plan view of an example application area with a high concentration of moisturizer.

Fig. 12 is a plan view of an example application area with a high concentration of moisturizer.

Fig. 13 is an explanatory diagram of the penetration of a moisturizer.

Fig. 14 is an explanatory schematic diagram of an embodiment in which an image of an application area with a high concentration of moisturizer is obtained by a near-infrared camera.

Description of Embodiments

[0014]

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. The dot pattern portion in the sectional views illustrates an adhesive as a bonding means for bonding the constituent members located on the front surface side and the rear surface side, and is formed by applying a hot-melt adhesive through continuous coating, roll coating, coating flow coating, apex coating, spiral coating, pattern coating (hot-melt adhesive transfer by letterpress printing) or the like. Instead or in addition, the fastening portion of the elastic member is formed by applying a comb spray gun, a SureWrap attachment, or the like to the outer peripheral surface of the elastic member. Examples of the hot melt adhesive include EVA (ethylene vinyl acetate copolymer) based agent, rubber based adhesive (elastomer based agent), pressure sensitive adhesive, polyolefin based agent and polyester/polyamide based agent, and these agents can be used without any special restrictions. As a bonding means for bonding the constituent members, a bonding means by welding materials such as heat sealing or ultrasonic welding can also be used.

[0015]

Fig. 1-6 illustrate an example of a pant-type disposable diaper. The present pant-type disposable diaper includes a rectangular front outer member 12F that defines at least a portion of a front body portion F disposed on the lower torso, a rectangular rear outer member 12B that defines at least a portion of a rear body portion B disposed on lower torso, and an inner member 200 located on the inner side of the outer members 12F and 12B so that it extends from the front outer member 12F to the rear outer member 12B through the crotch portion.

[0016]

By attaching both sides of the front outer member 12F to both sides of the rear outer member 12B to form the side seam portions 12A, the hole formed by the front and rear end portions of the outer members 12F and 12B becomes a waist opening WO through which the wearer's torso passes. , and the portion surrounded by the lower edges of the outer members 12F and 12B and the side edge of the inner member 200 on each side of the inner member 200 defined in the width direction becomes a leg hole LO through which the leg passes. The inner member 200 is a portion for absorbing and retaining excreta such as urine, and the outer members 12F and 12B are portions for providing support for the inner member 200 relative to the wearer's body. The reference numeral Y denotes the maximum length of the diaper in the unfolded state (the length in the front-to-back direction from the edge of the waist opening WO in the front body F to the edge of the waist opening WO in the rear body B), and the reference numeral X denotes the maximum width of the diaper in unfolded state.

[0017]

The pant-type disposable diaper in this embodiment has an area T located on the lower torso and is defined as an area that extends in the front-to-back direction (the area extending in the front-to-back direction from the waist opening WO to the upper end of the leg opening LO ) and has a side seam portion 12A, and an intermediate region L defined as a region extending in the front-back direction in the leg opening portion LO (between the region extending in the front-back direction and having the side seam portion 12A the front body portion F, and a region extending in the front-to-back direction and having a side seam portion 12A in the rear body portion B). The T area located on the lower torso may be divided into a "waist portion" W, which conceptually forms the edge of the waist opening, and a "below waist portion" U, which is a portion located lower than the waist portion W. Typically in the case where the zone T located on the lower part of the body has a boundary at which the tensile tension in the width direction WD changes (for example, the thinness of the elastic element changes or the degree of its stretch), the part located closer to the waist opening WO than the boundary closest to the waist opening WO is the waist portion W. In the case where there is no such boundary, the waist extension portion 12E extending such that it is closer to the waist opening WO than the absorbent portion 56 or the inner member 200 , is the waist portion W. The length in the front-back direction varies depending on the size of the product and can be determined accordingly. For example, the length of the waist portion W may be 15-40 mm, and the length of the lower waist portion U may be 65-120 mm. Meanwhile, each of both side edges of the intermediate region L tapers into a substantially U-shaped or curved shape so as to follow the shape of the periphery of the wearer's leg, and the wearer's leg extends through the location. As a result, the pant-type disposable diaper has a generally approximately hourglass shape when unfolded.

[0018]

(Internal element)

The inner member 200 can be of any shape, but in the illustrated embodiment it is rectangular. As illustrated in FIGS. 3-5, the inner member 200 includes a top sheet 30 which is intended to form a body side, a liquid impermeable sheet 11, and an absorbent member 50 disposed therebetween to constitute the main body. , having the function of absorption. Reference numeral 40 denotes an intermediate sheet (second sheet) positioned between the top sheet 30 and the absorbent member 50 to allow liquid that has passed through the top sheet 30 to rapidly move into the absorbent member 50. Reference numeral 60 denotes side assemblies 60 extending from both side assemblies. sides of the inner member 200 to come into contact with the periphery of the wearer's legs to prevent secretions from flowing out to both sides of the inner member 200.

[0019]

(Top sheet)

The top sheet 30 is liquid permeable, and examples of the top sheet 30 include perforated or non-perforated nonwoven material and porous plastic sheet. There are no particular restrictions on the fibers forming the starting material for a nonwoven fabric made from these materials. Examples of these fibers include synthetic fibers such as polyolefin fibers, including polyethylene and polypropylene, polyester fibers or polyamide fibers, regenerated fibers such as rayon or copper-ammonium, natural fibers such as cotton, and blended fibers. fiber and multi-component fiber, which use two or more types of these fibers. In addition, the nonwoven material can be produced by any processing method. Examples of the processing method include known methods such as the hydroentangling method, the spunbonding method, the thermal bonding method, the melt-blow method, the needlepunch method, the through-air bonding method, and the spot bonding method. For example, when softness and drape are required, spunbonding and hydrospun are the preferred processing methods. When bulk and softness are required, the through-air bonding method, the spot bonding method and the heat bonding method are the preferred processing methods.

[0020]

The top sheet 30 may be formed from a single sheet or from a multi-layer sheet obtained by gluing two or more sheets together. Likewise, the top sheet 30 may be formed from a single sheet or from two or more sheets with respect to the in-plane direction.

[0021]

Both side sides of the top sheet 30 may be folded toward the back surface side at the side edges of the absorbent member 50 or may extend from the side edges of the absorbent member 50 toward the side without being folded.

[0022]

To prevent deviation from the predetermined position with respect to the back surface side member or the like, it is desirable that the top sheet 30 be attached to the back surface side member by a bonding means based on welding of materials such as heat sealing or ultrasonic welding. , or using hot melt adhesive. In the illustrated example, the top sheet 30 is attached to the surface of the intermediate sheet 40 and the surface of the portion of the wrapping sheet 58 that is located on the front surface side of the absorbent body 56 by means of a hot melt adhesive applied to the rear surface of the top sheet 30.

[0023]

(Intermediate sheet)

To quickly move liquid that has passed through the top sheet 30, an intermediate sheet (also referred to as a "second sheet") 40 having a higher liquid transmission rate than the top sheet 30 can be placed into the absorbent component. The intermediate sheet 40 is used to quickly move the liquid. into the absorbent component to improve the absorption performance provided by the absorbent component and to prevent the phenomenon of "return" of absorbed liquid from the absorbent component. Intermediate sheet 40 may be omitted.

[0024]

Examples of the intermediate sheet 40 include a material similar to that of the top sheet 30, namely, spunbonded nonwoven fabric, spunbonded nonwoven fabric, SMS nonwoven fabric (spunbonded layer (S) - spunbonded layer (M). blown, - spunbond layer (S), cellulose fiber non-woven fabric, cellulose-rayon blend sheet, spot bonded non-woven fabric and crepe paper. In particular, a see-through air-bonded nonwoven material is preferred because it is voluminous. For a see-through air-bonded nonwoven fabric, it is preferable to use a multicomponent fiber having a core-sheath structure. In this case, the resin used for the core may be polypropylene (PP), but polyester (PET) having high rigidity is preferred. The basis weight is preferably 17-80 g/ ^m2 and more preferably 25-60 g/ ^m2 . The fiber forming the raw material for the nonwoven fabric preferably has a fineness of 2.0-10 dtex. To provide bulk to the nonwoven fabric, it is also preferable to use off-center eccentric structure fibers, hollow fibers, and eccentric structure hollow fibers as mixed fibers as all or part of the fibers forming the raw material.

[0025]

In the illustrated example, the intermediate sheet 40 is located in the center and has a smaller width than the width of the absorbent component 56, but it can be placed at its maximum width. The length of the intermediate sheet 40 in the front-to-back direction may be the same as the maximum length of the diaper, may be the same as the length of the absorbent body 50, or the intermediate sheet 40 may be within a short length region centered on a liquid receiving region .

[0026]

To prevent deviation from the predetermined position with respect to the back surface side member or the like, it is desirable that the intermediate sheet 40 be attached to the back surface side member by a bonding means based on welding of materials such as heat sealing or ultrasonic welding , or using hot melt adhesive. In the illustrated example, the intermediate sheet 40 is attached to the surface of the portion of the wrapping sheet 58 located on the front surface side of the absorbent component 56 by means of a hot-melt adhesive applied to the rear surface of the intermediate sheet 40.

[0027]

(Liquid impermeable sheet)

The material of the liquid impervious sheet 11 is not particularly limited, but examples of this material include a plastic film formed from a polyolefin resin such as polyethylene or polypropylene, a multilayer nonwoven fabric having a plastic film disposed on the surface of the nonwoven material, and a multilayer sheet obtained by applying a non-woven material or the like to a plastic film and attaching a non-woven material or the like to the plastic film. For the liquid impervious sheet 11, it is preferable to use a liquid impermeable and moisture permeable material that is effectively used for reasons related to preventing mustiness. As a moisture-permeable plastic film, a widely used microporous plastic film produced by mixing an inorganic filler into a polyolefin resin such as polyethylene or polypropylene, molding the mixture into a sheet, and then stretching the sheet in one or two axis directions. In addition, as the liquid impervious sheet 11, it is possible to use a nonwoven material that uses microdenier fiber, a nonwoven material that has increased impermeability by reducing the gap between the fibers by applying heat and pressure, and a sheet that has become impervious for liquids without the use of plastic film and through the application of a superabsorbent polymer, hydrophobic resin or water repellent. However, it is desirable to use a resin film to ensure sufficient bonding strength during bonding to the cover nonwoven material 13 described below through a hot-melt adhesive.

[0028]

The liquid impervious sheet 11 may have a width that matches the side of the rear surface of the absorbent member 50, as illustrated in the drawing, or may extend around both sides of the absorbent member 50 and extend to both sides of the top sheet 30's side surface. absorbent element 50 to increase leakage. The protruding portion suitably has a width of approximately 5-20 mm on each of the left and right sides.

[0029]

On the inside of the liquid impervious sheet 11, in particular on the surface located on the side of the absorbent component 56, a discharge indicator that changes color due to the absorption of liquid may be provided.

[0030]

(Side assemblies)

The side assemblies 60 extend along both sides of the inner member 200 throughout the front-to-back direction LD, are designed to prevent lateral leakage by being in contact with the periphery of the wearer's legs, and include what are commonly referred to as three-dimensional assemblies or flat assemblies.

[0031]

The side assemblies 60 illustrated in FIG. 1, 3 and 4 are so-called three-dimensional assemblies and rise from the side of the inner member 200 to the front surface side. In the side assemblies 60, the root portion side portion 60B rises obliquely toward the center defined in the width direction, and the apex side portion 60A relative to the intermediate portion ascends obliquely outward in the width direction. However, the side assemblies 60 are not limited to this and can be modified accordingly. For example, the side assemblies 60 may generally rise toward the center, defined in the width direction.

[0032]

More specifically, the side gathers 60 in the illustrated example are formed by folding a tape-shaped nonwoven gather material 62 having a length equal to the length of the inner member 200 in the fore-aft direction, twice in the width direction WD in the apex region, and attaching a plurality of elongate elastic members 63 the gathers to the folded/folded portion and between the sheets near the folded position at intervals in the width direction WD in a state in which the elastic members 63 of the gathers are stretched in the longitudinal direction. The base portion of the side gathers 60 opposite to their apical portion (the end portion opposite in the width direction WD to the folded portion of the sheet) is a root portion 65 attached to the side of the liquid impervious sheet 11, on the rear surface side thereof in the inner member 200, and a portion other than the root portion 65 are a main portion 66 extending from the root portion 65 (the portion located on the folded portion side). The main body 66 has a root-side portion 60B extending toward a center defined in the width direction, and an apex-side portion 60A formed by folding at the end of the root-side portion 60B and extending outward. in the width direction. In this embodiment, side assemblies 60 of the type of assemblies with surface contact are selected. However, side assemblies 60 of the line contact type assemblies that are not folded outward in the width direction may also be selected. Both portions of the main body 66 end in the front-to-back direction are lowered portions 67 attached to the side surface of the top sheet 30 in the lowered state. Meanwhile, the part intermediate in the front-to-back direction and located between them is a loose free part 68. The elastic gathering member 63 extending in the front-to-back direction LD is attached in a stretched state to at least the apical part of the free part 68.

[0033]

In the side gathers 60 with the above-described configuration, the tightening force generated by the elastic member 63 of the gathers acts such that it causes both end portions to move closer to each other in the front-to-back direction. However, both portions of the main body 66 end in the front-to-back direction are secured so that they do not rise, while the portion between them is a loose free portion 68. Therefore, only the free portion 68 is raised to come into contact with the body side , as illustrated by the arrow in FIG. 3. Specifically, when the root portion 65 is located on the rear surface side of the inner member 200, the free portion 68 is raised so that it "opens" outward in the width direction at and near the crotch portion. Consequently, the side assemblies 60 contact the periphery of the legs along the surface to improve the fit.

[0034]

Similar to the side gathers 60 in the illustrated example, in the folding embodiment, the body 66 includes a root-side portion 60B extending toward a center defined in the width direction and a portion 60A located at the side of the apical part is folded at the end of the root side part 60A and extends outward in the width direction, the apical part 60A is attached to the root side part 60B in the lowered state in the lowered parts area 67, and the root portion side portion 60B is attached to the top sheet 30 in the lowered state. At least one of a hot melt adhesive applied by various application methods and a material welding agent such as heat sealing or ultrasonic welding may be used to bond the opposing surfaces to each other in the lowered portion 67. In this case, attaching the portion 60B, root-side portion to the top sheet 30, and attaching the tip-side portion 60A to the root-side portion 60B may be accomplished by the same means or by different means. For example, one preferred option is to attach the root-side portion 60B to the top sheet 30 by means of a hot-melt adhesive and attach the tip-side portion 60A to the root-side portion 60B by welding the materials.

[0035]

(Absorbent element)

The absorbent member 50 includes an absorbent component 56 and a wrapping sheet 58 wrapping the entire absorbent component 56. The wrapping sheet 58 may also be omitted.

[0036]

(Absorbent component)

The absorbent component 56 may be formed by an accumulation of fibers. For this fiber cluster, in addition to clusters obtained by accumulating short fibers such as fluff pulp fibers or synthetic fibers, if necessary, it is also possible to use a long continuous fiber cluster obtained by opening a tow (bundle of fibers) of synthetic fibers such as cellulose acetate fibers. In the case of formation of fluff pulp fiber clusters or short fibers, the areal density of the fibers may be, for example, approximately 100-300 g/m ² . In the case of an accumulation of long continuous fibers, the surface density of the fibers may be, for example, approximately 30-120 g/m ² . In the case of synthetic fiber, the fineness is, for example, 1-16 dtex, preferably 1-10 dtex and more preferably 1-5 dtex. In the case of an accumulation of long continuous fibers, the long continuous fiber may be formed from a non-crimped fiber, but is preferably formed from a crimped fiber. The degree of crimp of the crimped fibers may be, for example, about 5-75 crimps, preferably 10-50 crimps, and more preferably 15-50 crimps per 2.54 cm. Evenly crimped fiber is often used. The ultra-high absorbency polymer particles are preferably dispersed and retained in the absorbent component 56.

[0037]

The absorbent component 5 6 may have a rectangular shape. However, as illustrated in FIG. 7 and the like, the absorbent body 56 preferably has an hourglass shape with a tapered portion 56N having a width less than the width of both sides of the absorbent body defined in the front-to-back direction in a portion intermediate to the front-to-back direction, since this improves the fit the absorbent component 56 itself and the side assemblies 60 to the periphery of the legs.

[0038]

The size of the absorbent member 56 can be determined accordingly as long as the absorbent member 56 extends in front, behind, to the right and to the left of the ureteral outlet location. However, the absorbent component 56 preferably extends to or near the peripheral edges of the inner member 200 in the back-to-back direction LD and the width direction WD. It should be noted that the reference numeral 56X denotes the maximum width of the absorbent component 56.

[0039]

(Superabsorbent polymer particles) The superabsorbent polymer particles may be contained in a portion of the absorbent component 56 or all of the absorbent component 56. The superabsorbent polymer particles encompass the “powder” in addition to the “particles.” The superabsorbent polymer particles used for this type of disposable diaper can be used as they are as superabsorbent polymer particles 54. For example, when performing screening by using a standard sieve with a mesh size of 500 μm (JIS Z 8801-1:2006 (JIS -Japanese Industrial Standard)), (performing shaking for five minutes), particles for which the proportion of particles remaining on a sieve, is 30% of the mass. or less. When performing screening using a standard sieve with a mesh size of 180 µm (JIS Z 8801-1:2006), (performing shaking for five minutes), particles for which the proportion of particles remaining on the sieve is 60% by weight are desired, or more.

[0040]

(Wrapping sheet)

In the case of using the wrapping sheet 58, the material thereof may be thin paper, particularly crepe paper, non-woven material, multi-layer non-woven material, pinhole sheet and the like. However, it is desirable that the wrapping sheet 58 be a sheet from which particles of the superabsorbent polymer do not fall out. In the case of using a non-woven material instead of crepe paper, a hydrophilic non-woven material with an SMS structure (SMS structure, SSMMS or the like structure) is particularly suitable, and polypropylene, a polyethylene-polypropylene composite material or the like can be used as the material. A nonwoven material having a basis weight of 5-40 g/ ^m2 , in particular 10-30 g/ ^m2 , is desired.

[0041]

The wrapping option of the wrapping sheet 58 can be determined accordingly. However, for reasons related to ease of manufacture, preventing ultra-high absorbency resin particles from leaking from the front and rear end edges and the like, it is preferred that the wrapping sheet 58 is wound in a cylindrical shape to surround the front and rear surfaces and both side surfaces of the absorbent body 56, allowing the front and rear end portions of the wrapping sheet 58 to project from the front and rear sides of the absorbent portion 56, and the wound and overlap portion and the overlap portion of the front and rear projection portions are bonded by a hot-melt adhesive or by a bonding means such as welding of materials .

[0042]

(Outer element)

The outer members 12F and 12B correspond, respectively, to a rectangular front outer member 12F forming at least a portion of the front main body F disposed on the lower torso and a rectangular rear outer member 12B forming at least a portion of the rear body B placed on the lower body torso. The front outer member 12F and the rear outer member 12B are not continuous on the crotch side and are separated from each other in the front-to-back direction LD. The separation distance 12d can be, for example, approximately 150-250 mm. The outer members 12F and 12B may be an integral outer member that extends continuously from the front main body F through the crotch to the back body B, as described in Patent Literature 4.

[0043]

Each of the outer members 12F and 12B has a portion provided on the lower torso which is a region extending in the front-to-back direction corresponding to a region T provided on the lower torso. In this embodiment, the size of the rear outer member 12B in the front-to-back direction is larger than the size of the front outer member 12F in the front-to-back direction, and the front outer member 12F does not have a portion that corresponds to the intermediate region L, but the rear outer member 12B has a portion C. covering the buttocks and extending from the T zone, located on the lower part of the body, towards the intermediate zone L.

[0044]

Each of the outer members 12F and 12B includes elastic members 15-19 designed to improve fit against the lower torso of the wearer, thereby forming a stretch region A2 that elastically stretches and contracts in the width direction WD along with the stretch and contraction of the elastic members . In the stretch zone A2 in the natural length state, the outer members 12F and 12B are contracted together with the contraction of the elastic member to form wrinkles or folds. When the elastic member is stretched in the longitudinal direction, it is possible to stretch the outer members 12F and 12B to a predetermined stretch degree at which the outer members 12F and 12B are stretched without wrinkles. In addition to the elongated elastic member (illustrated example) such as a rubber thread, a known elastic member such as a band member, a mesh member, or a film member can be used as the elastic members 15-19 without particular limitation. Either synthetic rubber or natural rubber can be used as elastic elements 15-19.

[0045]

The elastic members 15-19 in the illustrated example will be described in more detail. In the waist portion W of each of the outer members 12F and 12B, a plurality of elastic waist members 17 are attached at intervals in the front-back direction so that they are continuous throughout the entire extent in the width direction WD. One or more elastic waist members 17 located in an area adjacent to the below-waist portion U may overlap the inner member 200 or may be placed on both sides of the member defined in the width direction, excluding the area central to the width direction. and overlapping the inner element 200. As the elastic elements 17 of the waist part, it is preferable to place 2-15 rubber threads, in particular 4-10 rubber threads, each of which has a fineness of 155-1880 dtex, in particular approximately 470-1240 dtex (in the case of synthetic rubber. In the case of natural rubber, the cross-sectional area is 0.05-1.5 mm ² , in particular approximately 0.1-1.0 mm ² ) at intervals of 2-12 mm, in particular 3- 7 mm. As a result, the stretch ratio of the waist portion W in the width direction WD is preferably 150-400%, and particularly preferably approximately 220-320%. In the waist portion W, all of the waist portion elastic members 17 located in the front-back direction LD do not necessarily have the same fineness and the same degree of stretch. For example, the fineness and degree of stretch of the elastic elements 17 in the upper part of the waist portion W may be different from the fineness and degree of stretch of the elastic elements 17 in the lower part of the waist portion W.

[0046]

In the waist portion U, in each of the outer members 12F and 12B, a plurality of the waist portion elastic members 15 and 19, which are formed of elongated elastic members, are preferably spaced at intervals in the front-to-back direction. It is preferable to place, as elastic elements 15 and 19 of the part located below the waist, 5-30 rubber threads, each of which has a fineness of 155-1880 dtex, in particular approximately 470-1240 dtex (in the case of synthetic rubber. In the case of natural rubber cross-sectional area is 0.05-1.5 mm ² , in particular approximately 0.1-1.0 mm ² ), at intervals of 1-15 mm, in particular 3-8 mm. Therefore, the stretch ratio of the lower waist portion U in the width direction WD is preferably 200-350%, and particularly preferably about 240-300%.

[0047]

In the buttock covering portion C of the rear outer member 12B, an elastic covering member 16 formed from an elongated elastic member is preferably secured. The buttock covering part C is pulled towards the center determined in the width direction WD by the elastic member 16 of the covering part. It is preferable to place as the elastic element 16 of the closing part a rubber thread having a fineness of 155-1880 dtex, in particular approximately 470-1240 dtex (in the case of synthetic rubber. In the case of natural rubber, the cross-sectional area is 0.05-1.5 mm ² , in particular approximately 0.1-1.0 mm ² ). Therefore, the stretch ratio of the buttock covering portion C in the width direction WD is preferably 150-300%, and particularly preferably about 180-260%.

[0048]

In the above example, the outer members 12F and 12B are separated from each other in the front-to-back direction, but may be continuous with each other (not illustrated).

[0049]

(Moisturizer and its application)

To maintain the wearer's skin in a favorable condition and to prevent diaper dermatitis, it is desirable to apply a moisturizer to the top sheet 30 in an embodiment such as the example described later.

[0050]

Moisturizers containing mainly glycerin are suitable as moisturizers. When the moisturizer is applied to the outer surface of the top sheet 30 (at least a portion of the outer surface of the top sheet 30 contains moisturizer M), the moisturizer M protects the skin of the wearer.

In addition, Moisturizer M also has the function of reducing friction on the wearer's skin. As a result, when wearing a disposable diaper, the top sheet slides against the skin in accordance with changes in the wearer's posture, contact with the wearer's skin is ensured, and the leakage prevention effect is enhanced.

[0051]

The moisturizer containing primarily glycerin contains 70% by weight glycerin or more in the component composition and optionally contains one or more additives selected from the group consisting of an emulsifier, phosphate, paraffin and surfactant. As the surfactant, a nonionic surfactant of the ether type and a nonionic surfactant containing a copolymer of the ethylene oxide-propylene oxide copolymer (EO/PO) type are preferred.

[0052]

As schematically illustrated in FIG. 13, it is desirable that the top sheet 30 is a perforated nonwoven material in which a large number of holes 14 extending through the nonwoven material from the front surface to the rear surface are formed at intervals. When the top sheet 30 has holes 14 extending through the nonwoven material from the front surface to the back surface, the liquid stool component can be quickly absorbed into the absorbent member 50 having the absorbent component 56 through the holes 14, which is advantageous not only for reducing the stimulation perceived skin due to the liquid stool component remaining on the surface of the top sheet 30 to suppress diaper dermatitis, but also to prevent leakage from the leg portion or dorsal portion.

[0053]

According to the conventional diaper manufacturing method, the moisturizing agent M is applied to the top sheet 30 by coating or the like during the diaper manufacturing process, and thereafter, a large number of diaper articles are tightly packed. Due to this compaction of the diaper, as schematically illustrated in FIG. 13, a portion of the moisturizing agent M present on the top sheet 30 is transferred to the intermediate sheet 40 through the holes 14.

The intermediate sheet generally provides a higher rate of body fluid transmission than the top sheet 30. In addition, the moisturizer M, which contains primarily glycerol M, has a higher hydrophilicity than the hydrophilic diamide derivative. As a result, the moisturizing agent M, which contains mainly glycerin and is moved to the side of the intermediate sheet 40, acts as a means for drawing in body fluid from the side of the top sheet 30 or drawing in a loose stool component passing through the openings 14.

Therefore, the body fluid passing from the side of the top sheet 30 or the liquid stool component passing through the holes 14 is quickly directed toward the absorbent member 50, and the situation in which the body fluid such as the loose stool component is suppressed , remains on the surface of the top sheet 30. As a result, the stimulating effect perceived by the skin is reduced, and diaper dermatitis can be suppressed.

[0054]

The moisturizer performs its function by being applied to the area in contact with the wearer's skin. In the above embodiment, this location is the area between the side assemblies 60 and 60 illustrated in FIG. 7. That is, the area between the side assemblies 60 and 60 represents the possible application area Z in the present invention.

In other words, the applicationable zone Z is the exposed zone Z, which can be visually recognized directly from the side of the surface facing the user when the product is unfolded.

[0055]

The moisturizer can be applied to the appropriate area in the possible application zone Z (zone Z exposed to action). For example, as illustrated in FIG. 8, since the skin tends to be dry in zone Z1 on the side of the posterior main part B where the buttock zone is located, the amount of moisturizer applied can be increased in zone Z1, and since zone Z2 corresponding to the perineal part often has a large amount of moisture, the amount moisturizer applied can be reduced in zone Z2.

That is, the low concentration application zone has a plurality of application zones Z1 and Z2 having different concentrations of moisturizer in a back-to-back direction.

[0056]

With respect to the application of the moisturizer to the top sheet 30, it should be noted that the moisturizer may also be applied to the material of the top sheet 30 in a state prior to the joining of the top sheet 30 with the other constituent material of the diaper, for example, before the joining of the top sheet 30 to the constituent material of the side gathers 60 Therefore, the moisturizing agent can also be applied, for example, to the maximum width of the material of the top sheet 30 outside the possible application zone Z (the exposed zone Z), defined in the width direction. Based on this consideration and the like, it has been clarified that the moisturizer is applied to an exposed area that can be “at least” visually recognized directly from the user-facing surface when the product is unfolded.

[0057]

The perineal part comes into contact with the liquid stool component with high frequency. Considering that it is necessary to increase the amount of moisturizer applied to the perineal part to solve the problems associated therewith, as illustrated in FIG. 9, the applied amount in the central zone Z3 may be greater (the concentration in the central zone Z3 may be higher) than in the rear zone Z1 and the front zone Z2.

[0058]

As an option for the method of applying the moisturizer to the top sheet, an appropriate option such as non-contact type apex, spiral, curve, single fluid spray or dual fluid spray, contact application using a slot head contact type coating device can be selected , or application using a printing roller.

[0059]

On the other hand, when the amount (concentration) of moisturizer applied is increased, the moisturizer adheres excessively to the skin, causing the wearer to feel sticky, and there is a high likelihood of causing discomfort to the wearer.

Therefore, there is an upper limit to the amount of moisturizer applied.

[0060]

On the other hand, in the case of receiving a diaper coated with a moisturizer, for quality assurance reasons (i.e. from a production management point of view so as to eliminate defective products), it is very important to provide confirmation that the moisturizer is applied to the product in the process of production or not.

[0061]

Since the moisturizer contains moisture and moisture absorbs light in the near-infrared wavelength region, for this confirmation, for example, you can choose to install a near-infrared camera on the production line, take an image of the area where the moisturizer is applied, and confirm whether the moisturizer is present or not , based on the density level of the resulting image.

[0062]

However, through various experiments, it has been found that when the amount of moisturizer applied is small, it is impossible to detect the difference in density in the image taken by the near-infrared camera.

Therefore, when the amount (concentration) of moisturizer applied is increased so that a difference in density can be detected in the image taken by the near-infrared camera, the moisturizer will adhere excessively to the skin, which gives the wearer a sticky feeling, and there is high probability of creating discomfort for the wearer.

[0063]

To solve this problem, it has been found that it is preferable to form application zones Q with a high concentration of moisturizing agent in parts peripheral in the anterior-to-back direction and/or parts peripheral in the width direction in the exposed zone Z (possible application zone Z ) (see FIG. 7), and the moisturizer is preferably applied at a low concentration in a zone intermediate between the high concentration application zones Q and Q.

The reason for this is that even if there is a high concentration application area Q, this location is not a location where the moisturizer adheres excessively to the wearer's skin so as to cause a sticky feeling or discomfort to the wearer.

[0064]

For example, when selecting the options illustrated in FIG. 10-12, an image of a high concentration application zone Q can be obtained, and this zone Q can be detected by a near-infrared camera.

[0065]

Example according to FIG. 10 is an example in which high concentration application zones (designated zones) Q are formed on the front side and rear side of the top sheet 30. The low moisturizer concentration application zone MZ is located between the high concentration application zones (designated zones) Q and Q .

[0066]

Example according to FIG. 11 is an example in which high concentration application zones (designated zones) Q are formed on the left and right side portions of the top sheet 30. The low moisturizer concentration application zone MZ is located between the high concentration application zones (designated zones) Q and Q .

[0067]

Example according to FIG. 12 is an example in which high concentration application zones (designated zones) Q are formed on the front, rear, left and right sides of the top sheet 30. A low moisturizer concentration application zone MZ is located in a zone surrounded by application zones (designated zones) with high concentration.

[0068]

In the examples of FIGS. 10-12, in the low concentration application zone provided in the exposure zone Z (possible application zone Z), the moisturizer can be applied in the front-to-back direction at intervals in the width direction. Since in this embodiment, the moving direction of the production line and the flow direction of the applied moisturizer coincide with each other, production is easy.

[0069]

Fig. 14 illustrates an image acquisition scheme of a high concentration application zone (designated zone) Q. That is, for example, a near-infrared camera 100 is placed on a production line in which semi-finished disposable diapers with the application option of FIG. 10 are moved in the lateral direction corresponding to the direction of the arrow (direction to the right), and an image of the high concentration application zone (designated zone) Q is obtained.

[0070]

Near-infrared radiation typically has a wavelength ranging from 780 nm to 2500 nm. Water absorbs light in the wavelength range from 1400 nm to 1900 nm. Therefore, detection by the near-infrared camera 100 is effective.

[0071]

The inventor of the present invention performed the following experiments to determine whether a skin care agent, particularly a moisturizer, is included in the product or not, and performed various studies.

(1) A humectant containing glycerin is applied to the surface material (a hydrophilic through-bonded nonwoven fabric with a basis weight of 18 g/ ^m2 and a fiber fineness of 2.0/2.2 dtex) of the absorbent article by spraying two fluids and in the form of a peak, changing the concentration per unit area during application.

Application concentrations were 0.1 g/ ^m2 , 0.5 g/ ^m2 , 2.0 g/ ^m2 , 5 g/ ^m2 and 8.5 g/ ^m2 .

(2) Cut a sample with dimensions of 5 cm × 5 cm to prepare the test sample.

(3) Using a near-infrared camera (NIRCam-640SN) manufactured by Vision Sensing Co., Ltd., the test sample was illuminated (room light+external window light) and photographed.

[0072]

According to the above experiment, it was found that a moisturizer can be detected and recognized with sufficient sensitivity by the near-infrared camera 100 when the concentration of the applied moisturizer is 8.5 g/m ² (0.022 g/(5 cm × 5 cm) ) or more.

In addition, according to 10 adult observers, it was found that when the application concentration is 15 g/m ² (0.025 g/(5 cm x 5 cm)) or more, a sticky feeling is created.

It is desirable that the applied amount is 0.02-0.0 4 g/(5 cm × 5 cm).

[0073]

In an embodiment of the present invention, the application zone MZ with a low concentration of moisturizer is located in a zone surrounded by zones (designated zones) Qc with a high concentration of application.

It is desirable that in the low concentration application zone MZ the application concentration is 0.1-8.5 g/m ² . When the application concentration is excessively low, the effect of the moisturizer is insufficient, and when the application concentration is excessively high, a sticky feeling is produced.

[0074]

On the other hand, it is desirable that the ratio related to the humectant, that is, the ratio of the concentration in the high-concentration application zone (designated zone) Q to the concentration in the low-concentration application zone MZ, is 1.5 or more to ensure difference.

[0075]

<Explanation of terms in the description>

The following terms in the description have the following meanings unless otherwise stated in the description.

[0076]

“Anterior-posterior direction (longitudinal direction)” means the direction connecting the ventral side (front side) and dorsal side (posterior side), and “width direction” means the direction (left-right direction) orthogonal to the front-back direction.

[0077]

"Front side" means the side closest to the wearer's skin when wearing a pant-type disposable diaper. "Back side" means the side away from the wearer's skin when wearing a pant-type disposable diaper.

[0078]

"Front surface" means the surface of the element closest to the wearer's skin when wearing a pant-type disposable diaper. "Back surface" means the surface away from the wearer's skin when wearing a pant-type disposable diaper. [0079]

- “Stretch ratio” means the value obtained when the natural length is 100%.

[0080]

- “Gel strength” is determined as follows. 1.0 g of ultra-high absorbency polymer is added to 4 9.0 g of artificial urine (a mixture of 2% wt, urea, 0.8% wt, sodium chloride, 0.03% wt, calcium chloride dihydrate, 0.08% wt . magnesium sulfate heptate and 97.09 wt.% ion exchange water), and the resulting mixture is stirred with a stirrer. The gel thus formed is left for three hours in a thermohygrostat at a temperature of 40°C and a relative humidity (RH) of 60%. Thereafter, the temperature is returned to the indoor temperature, and the gel strength is determined by a density meter (Curdmeter-MAX ME-500, manufactured by I. Techno Engineering Co., Ltd.).

[0081]

- “Area density” is determined as follows. The sample or test piece is pre-dried and then left in the test chamber or apparatus under normal conditions (ambient temperature at test location 23±1°C and relative humidity 50±2%) to obtain a constant mass.

Pre-drying means bringing the mass of a sample or test piece to a constant mass in an environment with a temperature of 100°C. It should be noted that for fibers having a standard moisture content as a percentage of dry weight of 0.0%, pre-drying is not necessary. From a test piece having a constant mass, a sample of dimensions 100 mm × 100 mm is cut using a cutting template (100 mm × 100 mm). The mass of the sample is measured. The mass is multiplied by 10 to calculate the mass per square meter to be used as the surface density.

[0082]

- “Thickness” is measured automatically at a load of 0.098 N/cm ² and a pressure area of 2 cm ² using an automatic thickness gauge (KES-G5 with easy-to-use compression measurement program).

[0083]

- Water absorption capacity is determined in accordance with the JIS K7223-1996 standard "Test method for water absorption capacity of super absorbent polymer."

[0084]

- The water absorption rate represents the "time to end point" when performing the test according to JIS K7224-1996 "Test method for water absorption speed of super absorbent polymer" at using 2 g of ultra-high absorbency polymer and 50 g of physiological saline solution.

[0085]

- “Unfolded state” means a flat state with no contraction or sagging.

[0086]

- The dimensions of each part mean the size not in the natural length state, but in the unfolded state, unless otherwise stated.

[0087]

- When the environmental conditions for testing and measurement are not described, it is assumed that the test and measurement are performed in a test laboratory or device under normal conditions (at the test location, the ambient temperature is 23±1°C and the relative humidity is 50±2%).

Industrial applicability

[0088]

The present invention can be used not only for a pant-type disposable diaper, but also for a disposable diaper fastened with tapes, a disposable pad used when attached to a disposable diaper, and the like.

List of reference items

[0089]

11 Sheet, impermeable to liquids

12A Part with side seam

12V Rear outer element

12E Waist extended part

12F Front outer element

12F, 12V Outdoor element

12H Second sheet material

12S First sheet material

13 Covering non-woven material

15, 19 Elastic element of the part located below the waist

16 Elastic element of the closing part

17 Elastic waistband element

18 Optional elastic element 200 Inner element

30 Top sheet

40 Intermediate sheet

50 Absorbent element

56 Absorbent component

58 Wrapping sheet

60 Side assemblies

62 Non-woven fabric for gathers

Claims (17)

1. Disposable diaper containing: a top sheet forming a user-facing side surface, a liquid-impervious sheet located on the rear surface side, and an absorbent element located between them, wherein a moisturizing agent containing mainly glycerin is applied to the top sheet, the moisturizer application area is an exposed area that can be at least visually recognized directly from the user-facing surface when the product is unfolded, and the exposed area has application zones with a high concentration of wetting agent in at least one of the portions peripheral in the front-to-back direction and portions peripheral in the width direction, and an application zone with a low concentration of wetting agent in a zone intermediate between high concentration application areas. 2. Disposable diaper according to claim 1, wherein the low concentration application zone has a plurality of application zones having different concentrations of moisturizer in a back and forth direction. 3. Disposable diaper according to claim 1, wherein in the low concentration application area, the moisturizer is applied in a back-to-back direction at intervals in the width direction. 4. Disposable diaper according to claim 1, wherein the high concentration application zone has an applied moisturizer concentration of 8.5-15 g/ ^m2 . 5. A method for manufacturing a disposable diaper including a top sheet forming a user-facing side surface, a liquid impervious sheet located on the rear surface side, and an absorbent member located therebetween, the method comprising: applying a moisturizer containing mainly glycerin to the top sheet; And confirmation whether moisturizer is applied or not, wherein the area of application of the moisturizer is an area exposed to action, which can be at least visually recognized directly from the side of the surface facing the user when the product is unfolded, the exposed area has application zones with a high concentration of wetting agent in at least one of the portions peripheral in the front-to-back direction and portions peripheral in the width direction, and an application zone with a low concentration of wetting agent in a zone intermediate between high concentration application areas, and when confirming, images of high concentration application areas are obtained using a near-infrared camera, and whether a moisturizer is present or not is confirmed based on the density level of the acquired image.