JP7049154B2 - Disposable wear items - Google Patents

Description

The present invention relates to disposable wear items such as disposable diapers and menstrual napkins.

Most of the materials for disposable wear items such as disposable diapers are sheets such as non-woven fabrics and resin films, and in many of the areas where these sheets overlap, the sheets are bonded to each other via a hot melt adhesive.

Hot melt adhesives have a peculiar odor, and in order to reduce this, it is preferable to reduce the amount used. However, simply reducing the amount of the hot melt adhesive used is not preferable because the adhesive strength may be insufficient.

Japanese Patent No. 502742

Therefore, a main object of the present invention is to reduce the odor of the hot melt adhesive while suppressing the decrease in the adhesive force between the sheets.

The disposable wearable articles that have solved the above problems are as follows.
<Invention according to claim 1>
The first sheet and
A second sheet having a portion overlapping one surface of the first sheet,
In a disposable wearable article having an adhesive region to which the first sheet and the second sheet are adhered,
A plurality of first adhesive portions bonded via a hot melt adhesive are provided in the adhesive region at intervals, and are bonded between adjacent first adhesive portions via a cellulose nanofiber layer. A second adhesive part is provided,
Disposable wear goods characterized by that.

(Action effect)
The adhesive structure of the first sheet and the second sheet in this disposable wearable article is based on the first adhesive portion made of a hot melt adhesive. Here, by providing a plurality of first adhesive portions at intervals, it is possible to reduce the amount of the hot melt adhesive (that is, the odor generation source) used while ensuring the adhesion. However, with this alone, the first sheet and the second sheet are free in the portion between the adjacent first adhesive portions, and the unity as a whole is lacking. Therefore, in the present adhesive structure, a second adhesive portion bonded via the cellulose nanofiber layer is provided between the adjacent first adhesive portions. Since the cellulose nanofiber layer has adhesiveness by itself (that is, without an adhesive), it can take on an adhesive function although the adhesive strength differs depending on the object to be adhered. Moreover, since the cellulose nanofibers are fibrous, they have a high aspect ratio and have a relatively large specific surface area, so that they are excellent in physical adsorption to odors. Therefore, due to the presence of the second adhesive portion, the adjacent first adhesive portions are adhered to each other, and not only the decrease in the adhesive force between the sheets is suppressed, but also the odor of the hot melt adhesive is reduced by more than the decrease in the amount used. It is also possible to reduce the amount to.
In addition, Patent Document 1 describes an invention in which cellulose nanofibers are used for worn articles, which relates to a water-resistant and highly breathable composite sheet, and which relates to an adhesive structure of a sheet using a hot melt adhesive. It's not a thing.

<Invention according to claim 2>
It is a worn article having an absorber, a liquid-impermeable resin film covering the outside of the absorber, and an exterior nonwoven fabric covering the outside of the liquid-impermeable resin film.
One of the first sheet and the second sheet is the liquid-impermeable resin film, and the other is the exterior nonwoven fabric.
The first adhesive portion has a striped portion in which linear adhesive portions continuous in the front-rear direction are lined up at intervals in the width direction.
The second adhesive portion has a striped portion in which linear adhesive portions continuous in the front-rear direction are lined up at intervals in the width direction.
A part or all of the linear adhesive portion of the second adhesive portion is arranged between the adjacent linear adhesive portions in the first adhesive portion.
The disposable wearable article according to claim 1.

(Action effect)
In the worn article, the adhesive area between the liquid-impermeable resin film and the exterior non-woven fabric is relatively large, and the portion of the worn article is highly breathable to the outside. Therefore, this bonded portion is one of the main causes of the odor of the hot melt adhesive. Therefore, it is desirable to adopt the above-mentioned adhesive structure including the first adhesive portion and the second adhesive portion for this adhesive portion.
The cellulose nanofiber layer adheres strongly to the liquid-impermeable resin film, whereas it does not adhere strongly to the non-woven fabric like a hot melt adhesive. However, since the second adhesive portion made of the cellulose nanofiber layer is provided between the first adhesive portions made of the hot melt adhesive, the second adhesive portion is also difficult to peel off.
In addition, such worn items should be rolled or folded so that the adhering surface of the excrement is on the inside after use, and temporarily stored in a highly airtight storage container such as a sanitary box or a diaper storage container. When the amount of storage reaches a certain level, it is put in a garbage bag and discarded. In this case, there is a problem that a strong odor of excrement is generated from the worn article after use, which causes discomfort to the user. However, as described above, since the cellulose nanofiber layer of the second adhesive portion can physically adsorb the odor, it is also possible to adsorb and reduce the odor outside the worn article.

<Invention according to claim 3>
The width of the linear adhesive portion of the first adhesive portion is 1 to 20 mm, the interval in the width direction of the linear adhesive portion of the first adhesive portion is 1 to 20 mm, and the linear adhesive portion of the first adhesive portion is linearly adhered. The part consists of 1-20 g / m ² hot melt adhesive
The width of the linear adhesive portion of the second adhesive portion is 1 to 20 mm, the interval in the width direction of the linear adhesive portion of the second adhesive portion is 1 to 20 mm, and the linear adhesive portion of the second adhesive portion is linearly adhered. The moiety is made of the cellulose nanofibers of 0.3-15.0 g / m ² .
The disposable wearable article according to claim 2.

(Action effect)
The dimensions and the like of each part are not particularly limited, but in normal cases, it is preferably within the range described in this section.

<Invention according to claim 4>
The second adhesive portion is provided only in a range overlapping with the absorber.
The disposable wearable article according to claim 2 or 3.

(Action effect)
The portion having the cellulose nanofiber layer is inevitably hardened. On the skin side of the wearer, the hardness of the cellulose nanofiber layer is concealed by the cushioning property of the absorber in the region overlapping with the absorber. However, in the portion having no absorber, the hardness cannot be expected to be concealed by the absorber. Therefore, it is desirable that the second adhesive portion made of the cellulose nanofiber layer is provided only in the range where it overlaps with the absorber.

<Invention according to claim 5>
A part or the whole of the second adhesive portion is not covered with the hot melt adhesive.
The disposable wearable article according to any one of claims 1 to 4, characterized in that.

(Action effect)
Covering the cellulose nanofiber layer of the second adhesive portion with a hot melt adhesive is not desirable in order to improve the contact efficiency between the cellulose nanofiber layer and the odor. Therefore, it is preferable to have a structure in which a part or the whole of the second adhesive portion is not covered with the hot melt adhesive to suppress a decrease in contact efficiency between the cellulose nanofiber layer and the odor.

According to the present invention, it is possible to reduce the odor of the hot melt adhesive while suppressing the decrease in the adhesive force between the sheets.

It is a top view in the unfolded state which shows the inner surface of a tape type disposable diaper. It is a top view in the unfolded state which shows the outer surface of a tape type disposable diaper. FIG. 6 is a sectional view taken along line 6-6 of FIG. FIG. 7 is a cross-sectional view taken along the line 7-7 of FIG. FIG. 8 is a cross-sectional view taken along the line 8-8 of FIG. 9-9 is a cross-sectional view taken along the line 9-9 of FIG. FIG. 5 is a sectional view taken along line 5-5 of FIG. It is sectional drawing of the main part which shows the arrangement of adhesive and cellulose nanofibers. It is sectional drawing of the main part which shows the application example of adhesive and cellulose nanofibers. It is explanatory drawing which shows the arrangement of an adhesive and a cellulose nanofiber. It is explanatory drawing which shows the arrangement of an adhesive and a cellulose nanofiber. It is explanatory drawing which shows the arrangement of an adhesive and a cellulose nanofiber. It is explanatory drawing which shows the arrangement of an adhesive and a cellulose nanofiber. It is explanatory drawing which shows the arrangement of an adhesive and a cellulose nanofiber. It is explanatory drawing which shows the bonding process. It is sectional drawing which shows the arrangement of adhesive and cellulose nanofibers. It is explanatory drawing which shows the arrangement of an adhesive and a cellulose nanofiber. It is explanatory drawing which shows the arrangement of an adhesive and a cellulose nanofiber. It is explanatory drawing which shows the arrangement of an adhesive and a cellulose nanofiber.

Tape-type disposable diapers are composed of each component. Each component is composed of, for example, a liquid-impermeable resin film 11, an exterior nonwoven fabric 12, a target sheet 20, a top sheet 30, and other members. The adhesive described in detail below is used to bond each component. Adhesives have a peculiar odor by themselves, and there are parents (caregivers, wearers) who dislike the odor.

Hereinafter, a tape-type disposable diaper will be described as an example as a mode for carrying out the invention. 1 to 8 show an example of a tape-type disposable diaper, reference numeral X in the figure indicates the entire width of the diaper excluding the connecting tape, and reference numeral L indicates the total length of the diaper. Each component is joined by an adhesive as a joining means to be joined. The adhesive is a solid, bead, curtain, summit or spiral coating of hot melt adhesive, or pattern coat (transfer of hot melt adhesive by letterpress method), or the fixed part of the elastic member is replaced or this. At the same time, it is formed by applying an elastic member such as a comb gun or a sure wrap to the outer peripheral surface. As the hot melt adhesive, for example, there are types such as EVA type, adhesive rubber type (elastomer type), olefin type, polyester / polyamide type, etc., but they can be used without particular limitation (however, the same adhesive may be used. Does not include cellulose nanofibers). As a joining means for joining each component, a means by welding a material such as a heat seal or an ultrasonic seal can also be used. Specifically, in FIGS. 3, 4, and 8, the region where the liquid-impermeable resin film 11 and the exterior nonwoven fabric 12 are bonded may be bonded with the hot melt adhesive 81 and the cellulose nanofiber layer 15. ..

However, in the cross-sectional view, the liquid impermeable resin film 11 and the exterior nonwoven fabric 12 are bonded with the hot melt adhesive 81 and the cellulose nanofiber layer 15. The portion bonded with the hot melt adhesive 81 is shown in an oval pattern, and the portion bonded with the cellulose nanofiber layer 15 is shown in a dot pattern.

This tape-type disposable diaper includes an absorber 56, a liquid-permeable top sheet 30 that covers the front side of the absorber 56, a liquid-impermeable resin film 11 that covers the outside of the absorber 56, and a liquid-impermeable resin film. It has an exterior non-woven fabric 12 that covers the outside of the product and constitutes the outer surface of the product. Reference numeral F indicates a ventral portion located on the front side of the center in the anteroposterior direction, and reference numeral B indicates a dorsal portion located on the posterior side of the center in the anteroposterior direction.

Hereinafter, the materials and characteristic parts of each component will be described in order.

(Absorber)
The absorber 56 is a portion that absorbs and retains the excrement liquid, and can be formed by an aggregate of fibers. The fiber aggregate is a filament aggregate obtained by stacking short fibers such as cotton-like pulp and synthetic fibers, and opening tow (fiber bundle) of synthetic fibers such as cellulose acetate as needed. Can also be used. The fiber texture may be, for example, about 100 to 300 g / m ² in the case of stacking cotton-like pulp or staple fibers, and about 30 to 120 g / m ² in the case of filament aggregates. Can be done. In the case of synthetic fibers, the fineness is, for example, 1 to 16 dtex, preferably 1 to 10 dtex, and more preferably 1 to 5 dtex. In the case of a filament aggregate, the filament may be a non-crimped fiber, but is preferably a crimped fiber. The degree of crimping of the crimped fibers can be, for example, 5 to 75 pieces per 2.54 cm, preferably 10 to 50 pieces, and more preferably about 15 to 50 pieces. In addition, crimped fibers that have been uniformly crimped can be used.

(Highly absorbent polymer particles)
The absorber 56 may contain high-absorbent polymer particles in part or all of the absorber 56. The highly absorbent polymer particles include "powder" as well as "particles". As the highly absorbent polymer particles 54, those used for this kind of worn article can be used as they are. The particle size of the highly absorbent polymer particles is not particularly limited, but for example, sifting (shaking for 5 minutes) using a standard sieve (JIS Z8801-1: 2006) of 500 μm, and particles falling under the sieve by this sieving. When sifting (shaking for 5 minutes) using a 180 μm standard sieve (JIS Z8801-1: 2006), the proportion of particles remaining on the 500 μm standard sieve is 30% by weight or less, and the 180 μm standard sieve. It is desirable that the proportion of particles remaining on the top is 60% by weight or more.

The material of the highly absorbent polymer particles can be used without particular limitation, but those having a water absorption of 30 g / g or more are preferable. Highly absorbent polymer particles include starch-based, cellulosic-based and synthetic polymer-based ones, which are starch-acrylic acid (salt) graft copolymers, starch-acrylonitrile copolymer kendies, and cross-linking of sodium carboxymethyl cellulose. A substance, an acrylic acid (salt) polymer, or the like can be used. As the shape of the highly absorbent polymer particles, the commonly used powder or granular material is preferable, but other shapes can also be used.

As the highly absorbent polymer particles, those having a water absorption rate of 70 seconds or less, particularly 40 seconds or less, are preferably used. If the water absorption rate is too slow, so-called reversion, in which the liquid supplied into the absorber 56 returns to the outside of the absorber 56, is likely to occur.

Further, as the highly absorbent polymer particles, those having a gel strength of 1000 Pa or more are preferably used. As a result, even when the bulky absorber 56 is used, the sticky feeling after liquid absorption can be effectively suppressed.

The basis weight of the highly absorbent polymer particles can be appropriately determined according to the absorption amount required for the use of the absorber 56. Therefore, although it cannot be said unconditionally, it can be set to 50 to 350 g / m ² . If the basis weight of the polymer is less than 50 g / m ² , it becomes difficult to secure the absorption amount. If it exceeds 350 g / m ² , not only the effect is saturated, but also the excess of the highly absorbent polymer particles gives a jerky discomfort.

(Packaging sheet)
The absorber 56 can be incorporated as an absorbent element 50 wrapped in a packaging sheet 58 in order to prevent the highly absorbent polymer particles from coming off or to improve the shape retention of the absorber 56. As the packaging sheet 58, tissue paper, particularly crepe paper, non-woven fabric, polylami non-woven fabric, a sheet having small holes, or the like can be used. However, it is desirable that the sheet does not allow the highly absorbent polymer particles to escape. When a non-woven fabric is used instead of the crepe paper, a hydrophilic SMMS (spunbond / meltblown / meltblown / spunbond) non-woven fabric is particularly suitable, and polypropylene, polyethylene / polypropylene or the like can be used as the material. The fiber basis weight is preferably 5 to 40 g / m ² , especially 10 to 30 g / m ² .

As shown in FIG. 3, the packaging sheet 58 has a form in which the entire absorber 56 is wrapped by one sheet, or may be formed by wrapping the entire absorber 56 by a plurality of sheets such as two upper and lower sheets. 58 can be omitted.

(Top sheet)
The top sheet 30 has liquid permeability, and for example, a perforated or non-perforated non-woven fabric, a porous plastic sheet, or the like can be used. Further, among these, the non-woven fabric is not particularly limited as to what the raw material fiber is. For example, olefin-based fibers such as polyethylene and polypropylene, synthetic fibers such as polyester-based and polyamide-based fibers, recycled fibers such as rayon and cupra, natural fibers such as cotton, mixed fibers and composite fibers in which two or more of these are used. Etc. can be exemplified. Further, the nonwoven fabric may be produced by any processing. As the processing method, known methods such as a spunlace method, a spunbond method, a thermal bond method, a melt blown method, a needle punch method, an air through method, a point bond method and the like can be exemplified. For example, if flexibility and drapeability are required, the spunlace method is preferable, and if bulkiness and softness are required, the thermal bond method is preferable.

The top sheet 30 extends from the front end to the rear end of the product in the front-rear direction and extends laterally from the absorber 56 in the width direction WD. For example, the starting point of the rising gather 60 described later is more than the side edge of the absorber 56. If necessary, such as when the top sheet 30 is located on the center side in the width direction, the width of the top sheet 30 can be made shorter than the total width of the absorber 56, and the like can be appropriately deformed.

(Intermediate sheet)
In order to quickly transfer the liquid that has permeated the top sheet 30 to the absorber, an intermediate sheet (also referred to as a "second sheet") 40 having a faster liquid permeation speed than the top sheet 30 can be provided. The intermediate sheet 40 is for rapidly transferring the liquid to the absorber, enhancing the absorption performance by the absorber, and preventing the phenomenon of "reversion" of the absorbed liquid from the absorber. The intermediate sheet 40 may be omitted.

Examples of the intermediate sheet 40 include the same materials as the top sheet 30, spunlace non-woven fabric, spunbond non-woven fabric, SMS non-woven fabric, pulp non-woven fabric, mixed sheet of pulp and rayon, point-bonded non-woven fabric or crepe paper. In particular, the air-through non-woven fabric is preferable because it is bulky. It is preferable to use a composite fiber having a core-sheath structure for the air-through nonwoven fabric. In this case, the resin used for the core may be polypropylene (PP), but polyester (PET) having high rigidity is preferable. The basis weight is preferably 17 to 80 g / m ² , more preferably 25 to 60 g / m ² . The thickness of the raw material fiber of the non-woven fabric is preferably 2.0 to 10 dtex. In order to make the nonwoven fabric bulky, it is also preferable to use eccentric fibers having no core in the center, hollow fibers, and eccentric and hollow fibers as mixed fibers of all or a part of the raw material fibers.

Although the intermediate sheet 40 in the illustrated example is arranged in the center shorter than the width of the absorber 56, it may be provided over the entire width. Further, the intermediate sheet 40 may be provided over the entire length of the diaper, but may be provided only in the intermediate portion including the excretion position as shown in the illustrated example.

(Liquid impermeable resin film)
The liquid-impermeable resin film 11 is not particularly limited as long as it has moisture permeability, but for example, an inorganic filler is kneaded into an olefin-based resin such as polyethylene or polypropylene to form a sheet, and then uniaxial. Alternatively, a microporous sheet obtained by stretching in the biaxial direction can be preferably used. Needless to say, the liquid-impermeable resin film 11 does not include a non-woven fabric as a base material with improved waterproofness.

It is desirable that the liquid-impermeable resin film 11 extends in the same or wider range as the absorber 56 in the anteroposterior LD and the width direction WD, but if other impermeable means is present, it may be necessary. It is also possible to form a form that does not cover the end portion of the absorber 56 in the anteroposterior direction LD and the width direction WD. On the center side of the inner surface of the liquid-impermeable resin film 11 in the width direction, an indicator that develops or discolors due to the liquid content of excrement is provided so as to have a length of 1/3 to 3/4 of the total length L in the front-rear direction. Can be provided. As the indicator, a known indicator can be used without particular limitation. For example, the indicator may be a colorant that exhibits a color reaction upon contact with water in the excrement and / or a colorant that detects the pH in the water and exhibits a color reaction, or the liquid content of the excrement. A reaction in which the color disappears due to a reaction with, a reaction in which the colorant dissolves (disperses) in urine and bleeds or disappears, an ink or adhesive member containing other visual changes, or water or excretion. It can be composed of a sheet-like member containing a drug (indicator reaction means) that exhibits a visual change upon contact with a liquid component in an object. As a colorant that exhibits a color-developing reaction upon contact with water in the excrement, a water-soluble, water-decomposable dye or a leuco dye and a phenolic compound that develops the color of the leuco dye, an acidic substance, an electron-accepting substance, etc. It is possible to use a colorant composed of a color developer.

(Exterior non-woven fabric)
The exterior nonwoven fabric 12 covers the entire outer surface of the liquid-impermeable resin film 11 and gives the outer surface of the product a cloth-like appearance. The exterior nonwoven fabric 12 is not particularly limited, and the material fibers include, for example, olefin-based fibers such as polyethylene and polypropylene, synthetic fibers such as polyester-based and polyamide-based, recycled fibers such as rayon and cupra, and natural fibers such as cotton. As a processing method, a spunlace method, a spunbond method, a thermal bond method, an air-through method, a needle punch method, or the like can be used. However, long-fiber non-woven fabrics such as spunbonded non-woven fabrics, SMS non-woven fabrics, and SMMS non-woven fabrics are suitable from the viewpoint of achieving both touch and strength. The non-woven fabric can be used alone or in layers. In the latter case, it is preferable to bond the nonwoven fabrics to each other with a hot melt adhesive or the like. When a non-woven fabric is used, the fiber basis weight is preferably 10 to 50 g / m ² , especially 15 to 30 g / m ² .

(Get up gather)
In order to prevent excrement that travels laterally along the top sheet 30 and prevent so-called lateral leakage, rising gathers 60 that stand up on the wearer's skin side are provided on both sides of the inner surface widthwise WD. It is preferable to have. Of course, the rising gather 60 can be omitted.

When the rising gather 60 is adopted, its structure is not particularly limited, and any known structure can be adopted. The rising gather 60 of the illustrated example is composed of a gather sheet 62 substantially continuous in the width direction WD and an elongated gather elastic member 63 fixed to the gather sheet 62 in an extended state along the front-rear direction LD. ing. A water-repellent nonwoven fabric can be used as the gather sheet 62, and a rubber thread or the like can be used as the gather elastic member 63. As shown in FIGS. 1 and 2, a plurality of elastic members may be provided, and one elastic member may be provided for each.

The inner surface of the gather sheet 62 has a joint starting end in the width direction on the side portion of the top sheet 30, and the portion outside the joining starting end in the width direction is the inner surface of each side flap portion SF, that is, liquid opaque in the illustrated example. It is bonded to the side portion of the sex resin film 11 and the side portion of the exterior nonwoven fabric 12 located outside in the width direction by a hot melt adhesive or the like.

Around the legs, the inside of the rising gather 60 in the width direction from the joint start end is fixed on the top sheet 30 at both ends in the front-rear direction of the product, but the part in between is a non-fixed free part, and this free part is It rises due to the contraction force of the elastic member 63 and comes into close contact with the body surface.

(End flap part, side flap part)
The tape-type disposable diaper of the illustrated example has a pair of end flap portions EF having no absorber 56 and extending laterally from both side edges of the absorber 56, respectively, extending to the front side and the rear side of the absorber 56. It has a pair of side flap portions SF that do not have an absorber 56.

(Plane gather)
A side elastic member 64 made of an elongated elastic member such as a rubber thread is fixed to each side flap portion SF in a state of being extended along the front-rear direction LD, whereby the leg circumference portion of each side flap portion SF is fixed. Is configured as a plane gather. As shown in the illustrated example, the leg circumference elastic member 64 is provided between the gather sheet 62 and the liquid-impermeable resin film 11 on the outer side of the joint portion of the gather sheet 62 in the width direction near the joint start end, and also has a side flap. It can also be provided between the liquid-impermeable resin film 11 and the exterior nonwoven fabric 12 in the portion SF. As shown in the illustrated example, a plurality of elastic members around the legs 64 may be provided on each side, or only one elastic member 64 may be provided on each side.

(Connecting tape)
The side flap portion SF in the dorsal side portion B is provided with a connecting tape 13 that is detachably connected to the outer surface of the ventral side portion F. When wearing the diaper 10, the connecting tape 13 is rotated from both sides of the waist to the outer surface of the ventral portion F, and the connecting portion 13A of the connecting tape 13 is connected to an appropriate position on the outer surface of the ventral portion F.

The structure of the connecting tape 13 is not particularly limited, but in the illustrated example, the tape mounting portion 13C fixed to the side flap portion SF, the sheet base material forming the tape main body portion 13B protruding from the tape mounting portion 13C, and this sheet. It has a connecting portion 13A with respect to the ventral side provided in the middle portion in the width direction of the tape main body portion 13B of the base material, and the tip side from the connecting portion 13A is a knob portion.

As the connecting portion 13A, a hook material (male material) for a mechanical fastener (hook-and-loop fastener) may be provided, or an adhesive layer may be provided. The hook material has a large number of engaging protrusions on its connecting surface, and the shapes of the engaging protrusions are (A) -shaped, (B) J-shaped, (C) mushroom-shaped, and (D). There are T-shapes, (E) double J-shapes (shapes in which J-shapes are joined back to back), and the like, but any shape may be used.

Further, as the sheet base material forming the tape mounting portion 13C to the tape main body portion 13B, a non-woven fabric, a plastic film, a polylami non-woven fabric, paper or a composite material thereof can be used, but the fineness is 1.0 to 3.5 dtex. A spunbonded non-woven fabric, an air-through non-woven fabric, or a spunlaced non-woven fabric having a texture of 20 to 100 g / m ² and a thickness of 1 mm or less is preferable.

(Target sheet)
It is preferable to provide a target sheet 20 having a target for facilitating the connection at the connection portion of the connection tape 13 in the ventral portion F. As the target sheet 20, when the connecting portion 13A is a hook material, a target sheet 20 having a large number of loop threads provided on the surface of a sheet base material made of a plastic film or a non-woven fabric so that the engaging protrusions of the hook material are entangled can be used. Further, in the case of the pressure-sensitive adhesive layer, a sheet base material made of a plastic film having a smooth surface, which is highly adhesive, can be used after being peeled off. Further, when the connecting portion of the connecting tape 13 in the ventral portion F is made of a nonwoven fabric, for example, when the exterior nonwoven fabric 12 is provided as shown in the illustrated embodiment, the target sheet 20 is omitted and the hook material is used as the fiber of the exterior nonwoven fabric 12. It can also be entwined and connected. In this case, the target sheet 20 as a mark may be provided between the exterior nonwoven fabric 12 and the liquid-impermeable resin film 11.

(Cellulose nanofiber)
Cellulose nanofibers refer to fine cellulose fibers obtained by defibrating pulp fibers, and generally refer to cellulose fibers containing cellulose fine fibers having an average fiber width of nano size (1 nm or more and 1000 nm or less). Those having an average fiber width (median diameter) of 100 nm or less are preferable, and those having an average fiber width (median diameter) of 10 to 60 nm are particularly preferable. Cellulose fibers are composed of β-glucose bound innumerably in a chain mainly by β-1,4 glycosidic bonds. β-glucose has an —H group, an —OH group and the like.

The odor reducing effect of cellulose nanofibers is better than the large amount of cellulose nanofibers, but if the amount is too large, the product becomes unnecessarily hard. Therefore, the coating amount of the cellulose nanofibers is preferably about 0.1 to 15.0 g / m ² and more preferably about 0.3 to 15.0 g / m ² with respect to the adhesive region 82.

To apply the cellulose nanofibers, the cellulose nanofibers are dissolved in a solvent to prepare a cellulose nanofiber dispersion liquid, and this cellulose nanofiber dispersion liquid is applied onto a target sheet such as a liquid impermeable resin film 11 and dried. It can be manufactured by a known method such as adhesion formation on a target sheet. When the liquid cellulose nanofibers are applied to a fiber sheet such as paper or non-woven fabric by the manufacturing method as described above, the cellulose nanofibers are concentrated on the surface of the sheet, although the cellulose nanofibers partially permeate into the sheet. The cellulose nanofiber layer 15 can be adhered and formed on the surface. The solvent for dispersing the cellulose nanofibers is not particularly limited, but a volatile organic solvent such as acetone can be used in addition to a lower alcohol such as water and ethanol.

The cellulose nanofiber dispersion liquid is formed by dispersing cellulose nanofibers in water. The concentration (mass / volume) of the cellulose nanofiber dispersion is preferably 0.1 to 10%, more preferably 1.0 to 5.0%, and 1.5 to 3.0%. Is particularly preferable. If the concentration is lower than 0.1%, the basis weight of the cellulose nanofiber layer 15 becomes too low. If the concentration is higher than 10%, the viscosity of the cellulose nanofiber dispersion is high and it is difficult to apply.

The B-type viscosity (60 rpm, 20 ° C.) of the cellulose nanofiber dispersion is, for example, 700 cps or less, preferably 200 cps or less, and more preferably 50 cps or less. By keeping the B-type viscosity of the cellulose nanofiber dispersion liquid low in this way, the cellulose nanofibers are uniformly applied to the sheet surface, and the surface property of the sheet is uniformly improved.

For the application of the cellulose nanofiber dispersion liquid, in addition to spraying on the target surface, a transfer method such as a letterpress method can also be used.

The cellulose nanofiber dispersion liquid can be applied to any of the above-mentioned sheets. In particular, the liquid-impermeable resin film 11 can be formed by kneading an inorganic filler in an olefin-based resin to form a sheet, and in this case, it has hydrophobicity. When the cellulose nanofiber layer 15 is formed on the liquid-impermeable resin film 11, the cellulose nanofiber layer 15 becomes a film, so that the water-impervious and strength of the liquid-impermeable resin film 11 is improved and the elongation is lowered. There is an advantage to do.

The liquid-impermeable resin film 11 is composed of a large number of constituent units such as characters (size, brand name, maker name, pattern name, etc.) that are regularly repeated in the front-back direction LD and the width direction WD, and a pattern. In addition to continuous decorative printing, intermittent decorative printing that is placed only on one or both of the front and back of the product, such as product logos, character pictures, photographs, etc., may be applied. When doing so, it is desirable that the elongation of the liquid-impermeable resin film 11 is small.

(Viscosity of cellulose nanofibers)
Starch is a chain of innumerable α-glucose bound mainly by α-1,4 glycosidic bonds. Starch becomes viscous when dispersed in water at a predetermined concentration. Cellulose fibers are composed of β-glucose, which is similar to α-glucose, bound innumerably in a chain mainly by β-1,4 glycosidic bonds. By dispersing the cellulose nanofibers in water at a predetermined concentration, the cellulose nanofiber dispersion liquid becomes viscous.

By using the hot melt adhesive 81 and the cellulose nanofiber layer 15 in combination, for example, as shown in FIG. 3, each component of the diaper (for example, the liquid-impermeable resin film 11 and the exterior nonwoven fabric 12) is bonded. Can be used as a means. In the figure, an adhesive portion bonded via a cellulose nanofiber layer 15 is provided between adjacent linear adhesive portions of the hot melt adhesive 81. Since the cellulose nanofiber layer has adhesiveness by itself (that is, without an adhesive), it can take on an adhesive function although the adhesive strength differs depending on the object to be adhered. Since the hot melt adhesive 81 is applied at intervals, the amount of the hot melt adhesive 81 used can be smaller than that in the conventional case where the hot melt adhesive 81 is applied over the entire surface of the adhesive region 82. It is economical.

(Odor reduction effect)
Cellulose nanofibers have the effect of reducing odor. Cellulose nanofibers generally have a fiber width of 4 nm or more and 1000 nm or less, a fiber length of 5 μm or more, a high aspect ratio (low one is 5 or more, high one is 1250 or more), and a large specific surface area and physical properties. Excellent in adsorption. The odor is physically adsorbed on the surface of the cellulose nanofibers by the van der Waals force. Then, the odor once physically adsorbed remains adsorbed on the surface of the cellulose nanofibers and does not diffuse, so that the odor is reduced.

Here, a method for measuring the average fiber width of cellulose nanofibers will be described.
First, 100 ml of an aqueous dispersion of cellulose nanofibers having a solid content concentration of 0.01 to 0.1% by mass is filtered through a membrane filter made of Teflon (registered trademark), and the solvent is once with 100 ml of ethanol and three times with 20 ml of t-butanol. Replace.

Next, it is freeze-dried and coated with osmium to prepare a sample. This sample is observed by an electron microscope SEM image at a magnification of 5000 times, 10000 times or 30000 times (in this example, a magnification of 30000 times) depending on the width of the constituent fibers. Specifically, two diagonal lines are drawn on the observation image, and three straight lines passing through the intersections of the diagonal lines are arbitrarily drawn. Further, a total of 100 fiber rods intersecting with these three straight lines are visually measured. Then, the medium diameter (median diameter) of the measured value is taken as the average fiber width. The diameter is not limited to the medium diameter of the measured value, and for example, the number average diameter or the mode diameter (mode diameter) may be used as the average fiber diameter.

Pulp fibers that can be used for the production of cellulose nanofibers include chemical pulps such as broadleaf tree pulp (LBKP) and coniferous tree pulp (NBKP), bleached thermomechanical pulp (BTMP), stone ground pulp (SGP), and pressurized stone ground pulp. (PGW), Refiner Grand Pulp (RGP), Chemi Grand Pulp (CGP), Thermo Grand Pulp (TGP), Grand Pulp (GP), Thermo Mechanical Pulp (TMP), Chemi Thermo Mechanical Pulp (CTMP), Refiner Mechanical Pulp ( Manufactured from machine pulp such as RMP), brown waste paper, kraft envelope blind paper, magazine waste paper, newspaper waste paper, leaflet waste paper, office waste paper, cardboard waste paper, upper white waste paper, Kent waste paper, imitation waste paper, ground ticket waste paper, sashimi waste paper, etc. Examples thereof include used paper pulp and deinked pulp (DIP) obtained by deinking waste paper pulp. These may be used alone or in combination of a plurality of types as long as the effects of the present invention are not impaired. Further, the pulp fiber obtained by subjecting it to a chemical treatment such as carboxymethylation may be used.

Examples of the method for producing cellulose nanofibers include mechanical methods such as a high-pressure homogenizer method, a microfluidizer method, a grinder grinding method, a bead mill freeze-grinding method, and an ultrasonic defibration method, but are limited to these methods. is not. Further, nanofiber formation is promoted by the combined use of TEMPO oxidation treatment, phosphoric acid esterification treatment, acid treatment and the like.

<First Embodiment>
In the conventional bonding of various constituent members with an adhesive, the hot melt adhesive 81 is applied to a region (referred to as an adhesive region 82) to which the constituent members are to be bonded, and two specific constituent members are bonded to each other. For example, assuming that the two specific components are the liquid-impermeable resin film 11 and the exterior non-woven fabric 12, when the liquid-impermeable resin film 11 and the exterior non-woven fabric 12 are to be bonded, the hot-melt adhesive 81 is applied to the bonding region 82. Then, the liquid impermeable resin film 11 and the exterior non-woven fabric 12 are adhered to each other.

On the other hand, in the first embodiment of the present invention, as shown in FIGS. 9, 10, 14, and the like, hot-melt adhesive is bonded in a striped manner within the adhesive region 82 (within the range surrounded by the quadrangle 82 in FIG. 10). It is a form in which the agent 81 is arranged. In the adhesive region 82, the hot melt adhesive 81 and the cellulose nanofiber layer 15 are linearly arranged in the front-rear direction LD. Then, the linear adhesive portion of the hot melt adhesive 81 and the linear adhesive portion of the cellulose nanofiber layer 15 are alternately arranged in the width direction WD. However, it is not always necessary to arrange them alternately, and the linear adhesive portion of the hot melt adhesive 81 is next to a plurality of linear adhesive portions of the cellulose nanofiber layer 15 in the front-rear direction LD arranged side by side in the width direction WD. A plurality of linear adhesive portions of the cellulose nanofiber layer 15 are arranged side by side next to the linear adhesive portion of the hot melt adhesive 81, and next to the linear adhesive portion of the hot melt adhesive 81. It may be in the form in which the adhesive portion is arranged. The gap between the linear adhesive portion of the hot melt adhesive 81 and the linear adhesive portion of the cellulose nanofiber layer 15 may not be provided, or a slight gap may be provided. Here, the linear adhesive portion (first adhesive portion in the claim) of the hot melt adhesive 81 is a sheet such as a liquid impermeable resin film 11 in which the hot melt adhesive 81 is linearly applied and adhered. Refers to the part. The linear adhesive portion (second adhesive portion in the claim) of the cellulose nanofiber layer 15 refers to a portion where the cellulose nanofiber dispersion liquid is linearly applied to a sheet such as a liquid impermeable resin film 11 and adhered. ..

The width 81A of the linear adhesive portion of the hot melt adhesive 81 is not particularly limited, but may be 1 to 20 mm, and the interval 81B of the linear adhesive portions of the hot melt adhesive 81 may be 1 to 20 mm. Further, the width 15A of the linear adhesive portion of the cellulose nanofiber layer 15 may be 1 to 20 mm, and the spacing 15B of the linear adhesive portions of the cellulose nanofiber layer 15 may be 1 to 20 mm. The dimensions of each part are usually easy to form within this range.

Further, both side edge portions of the adhesive region 82 (both side edge portions in the width direction WD of FIG. 10) may be linear adhesive portions of the hot melt adhesive 81. This is because, in such a form, the edge portions on both sides thereof are adhered by the hot melt adhesive 81, and the liquid impermeable resin film 11 and the exterior nonwoven fabric 12 are not easily peeled off. However, the edge portions on both sides of the adhesive region 82 do not necessarily have to be the linear adhesive portion of the hot melt adhesive 81, and may of course be the linear adhesive portion of the cellulose nanofiber layer 15. The adhesive region 82 is a region where the outer surface of the liquid-impermeable resin film 11 and the inner surface of the exterior nonwoven fabric 12 overlap.

Further, the cellulose nanofiber layer 15 can be provided only in the range where it overlaps with the absorber 56. The portion having the cellulose nanofiber layer 15 is inevitably hardened. On the skin side of the wearer, the hardness of the cellulose nanofiber layer 15 is concealed by the cushioning property of the absorber in the region overlapping with the absorber 56. However, in the portion having no absorber 56, the hardness cannot be expected to be concealed by the absorber 56. Therefore, it is desirable that the cellulose nanofiber layer 15 is provided only in the range where it overlaps with the absorber 56.

The extending direction of the linear adhesive portion of the hot melt adhesive 81 and the linear adhesive portion of the cellulose nanofiber layer 15 is not particularly limited, and is not limited to the front-rear direction LD, but may be the width direction WD or the oblique direction. .. Further, the shape of the linear adhesive portion of the hot melt adhesive 81 and the linear adhesive portion of the cellulose nanofiber layer 15 may be rectangular, zigzag, corrugated or the like.

<Second Embodiment>
In the second embodiment, as shown in FIG. 11, the hot melt adhesive 81 is linearly arranged on both side edge portions of the adhesive region 82 (both side edge portions in the width direction WD of FIG. 11). A cellulose nanofiber layer 15 is provided in a region sandwiched between the linear adhesive portions of the two hot melt adhesives 81 arranged at the edge portions on both sides in the width direction WD. With such a form, the amount of the hot melt adhesive 81 applied can be significantly reduced. Further, since the cellulose nanofiber layer 15 is provided over a relatively large area, the odor generated from the hot melt adhesive 81 can be effectively reduced.

As shown in FIG. 11, the region to which the cellulose nanofiber dispersion liquid is applied may extend to almost the entire surface of the region sandwiched between the linear adhesive portions of the two hot melt adhesives 81, but is not limited to this. .. For example, the cellulose nanofiber dispersion may be arranged in stripes (see FIG. 17). The width 15A of each linear adhesive portion of the cellulose nanofiber layer 15 is not particularly limited, but may be, for example, 1 to 20 mm, and the distance between adjacent linear adhesive portions 15B is not particularly limited, but may be, for example, 1 to 20 mm. .. Further, the width 15A of the linear adhesive portions of each of the cellulose nanofiber layers 15 and the interval 15B of the adjacent linear adhesive portions can be made constant, or can have different widths and intervals. By doing so, the coating amount of the cellulose nanofibers can be relatively reduced, which is economical.
Note that FIG. 8 is a cross-sectional view of a main part showing the second embodiment. As shown in the figure, the liquid-impermeable resin film 11 and the exterior nonwoven fabric 12 are bonded to the outer end edge portions 21 in the width direction WD with a hot melt adhesive 81. Then, the cellulose nanofiber dispersion liquid is applied to the central side of the both end edges 21. The width 81A of the linear adhesive portion of the hot melt adhesive 81 is not particularly limited, but may be 1 to 20 mm.

<Third Embodiment>
The third embodiment is a form in which the hot melt adhesive 81 and the cellulose nanofiber layer 15 are arranged in a checkered pattern as shown in FIG. Since the hot melt adhesive 81 is arranged next to the cellulose nanofiber layer 15 on all sides (LD in the front-rear direction and WD in the width direction), the liquid-impermeable resin film 11 and the exterior nonwoven fabric 12 are reliably adhered to each other. At the same time, since the cellulose nanofiber layers 15 are arranged on all four sides of the hot melt adhesive 81, the odor of the hot melt adhesive 81 is effectively reduced by the cellulose nanofiber layers 15. It should be noted that the hot melt adhesive 81 may be linearly arranged on both end edges 21 of the adhesive region 82 (both end edges in the width direction WD of FIG. 12) (not shown). The width 81A of the linear adhesive portion of the hot melt adhesive 81 arranged at both end edges 21 of the adhesive region 82 is not particularly limited, but may be 1 to 20 mm.

<Fourth Embodiment>
The fourth embodiment has a form in which the cellulose nanofiber layers 15 are arranged in a grid pattern as shown in FIG. The hot melt adhesive 81 is placed in the space in the lattice. Since the hot melt adhesive 81 is arranged in a large number of spaces in the lattice, the entire area of the adhesive region 82 is reliably adhered.

Further, as a form similar to the fourth embodiment, a form in which the hot melt adhesive 81 is arranged in a grid pattern (not shown) can be exemplified. In this case, the cellulose nanofiber layer 15 is arranged in the region surrounded by the lattice. The grid is not limited to a square, but includes a rectangle and, of course, an orthorhombic grid. The width of the grid lines and the width of the adjacent grid lines are not particularly limited. For example, the width of the grid lines can be 1 to 20 mm, and the width of adjacent grid lines can be 1 to 20 mm.

<Fifth Embodiment>
A hot melt adhesive 81 is applied to the adhesive region 82 of the liquid impermeable resin film 11, a cellulose nanofiber layer 15 is applied thereto, and the applied liquid impermeable resin film 11 and the exterior nonwoven fabric 12 are adhered to each other. The regions 82 can be adhered to form a sheet. The adhesive portion of the hot melt adhesive 81 has a striped portion in which linear adhesive portions continuous in the front-rear direction LD are lined up at intervals in the width direction WD. Further, the adhesive portion of the cellulose nanofiber layer 15 has a striped portion in which linear adhesive portions continuous in the front-rear direction LD are lined up at intervals in the width direction WD. Then, it is possible that a part or all of the adhesive portion of the cellulose nanofiber layer 15 is not covered with the hot melt adhesive 81 (see FIG. 19). In other words, between the sheets to be bonded, a part or all of the hot melt adhesive 81 may overlap with a part of the cellulose nanofiber layer 15, and a part or all of the hot melt adhesive 81 may be cellulose. It does not have to overlap all of the nanofiber layer 15.
The width 81A of the linear adhesive portion of the hot melt adhesive 81 is not particularly limited, but may be 1 to 20 mm, and the interval 81B of the linear adhesive portions of the hot melt adhesive 81 may be 1 to 20 mm. Further, the width 15A of the linear adhesive portion of the cellulose nanofiber layer 15 may be 1 to 20 mm, and the spacing 15B of the linear adhesive portions of the cellulose nanofiber layer 15 may be 1 to 20 mm. The dimensions of each part are usually easy to form within this range.
Covering the bonded portion of the cellulose nanofiber layer 15 with the hot melt adhesive 81 is not desirable in order to improve the contact efficiency between the cellulose nanofiber layer 15 and the odor. Therefore, it is preferable to have a structure in which a part or the whole of the adhesive portion of the cellulose nanofiber layer 15 is not covered with the hot melt adhesive 81, and the decrease in the contact efficiency between the cellulose nanofiber layer 15 and the odor is suppressed.

As described above, in the first to fifth embodiments, the adhesion between the liquid-impermeable resin film 11 and the exterior nonwoven fabric 12 is shown as an example. Here, one of the first sheet and the second sheet in the claim is a liquid-impermeable resin film 11, and the other is an exterior nonwoven fabric 12. For example, when the first sheet is a liquid-impermeable resin film 11, the second sheet is the exterior nonwoven fabric 12. When the first sheet is the exterior nonwoven fabric 12, the second sheet is the liquid-impermeable resin film 11. However, the present invention is not limited to this form, and for example, when two exterior nonwoven fabrics 12 (exterior nonwoven fabric 12a and exterior nonwoven fabric 12b) are provided, the first sheet can be the exterior nonwoven fabric 12a and the second sheet can be the exterior nonwoven fabric 12b. ..
The texture of the hot melt adhesive 81 on the linear adhesive portion is not particularly limited, but is usually 1 to 20 g / m ² , and the texture of the cellulose nanofiber layer 15 on the linear adhesive portion is not particularly limited, but in the normal case. Should be 0.3 to 15.0 g / m ² .

(Adhesion process)
An example of a method of adhering the liquid-impermeable resin film 11 and the exterior nonwoven fabric 12 will be described with reference to FIG. First, a plurality of hot melt adhesives 81 are applied to the adhesive region 82 of the liquid impermeable resin film 11 at intervals in the width direction WD so as to be distributed in the front-rear direction LD. Then, a plurality of linear adhesive portions of the hot melt adhesive 81 are arranged (FIG. 15 (a)). After that, the cellulose nanofiber layers 15 are provided so as to be arranged in parallel in the front-rear direction so as to fill the same interval (FIG. 15 (b)). Then, a plurality of linear adhesive portions of the cellulose nanofiber layer 15 are arranged. Next, the exterior nonwoven fabric 12 is adhered to the adhesive region 82 of the liquid impermeable resin film 11 with a roller 83 or the like (FIG. 15 (c)) and dried. As a result, the hot melt adhesive 81 and the cellulose nanofiber layers 15 are alternately arranged side by side in the adhesive region 82 of the liquid impermeable resin film 11.

It is also possible to reverse the order in which the hot melt adhesive 81 and the cellulose nanofiber layer 15 are arranged. First, a plurality of cellulose nanofiber layers 15 are applied to the adhesive region 82 of the liquid-impermeable resin film 11 at intervals in the width direction WD so as to be arranged in the front-rear direction LD. A plurality of linear adhesive portions of the cellulose nanofiber layer 15 are arranged. After that, a plurality of hot melt adhesives 81 are applied so as to be arranged in the front-rear direction LD so as to fill the same interval. A plurality of linear adhesive portions of the hot melt adhesive 81 are arranged. Next, the exterior nonwoven fabric 12 is adhered to the adhesive region 82 of the liquid impermeable resin film 11 with a roller 83 or the like and dried. As a result, the hot melt adhesive 81 and the cellulose nanofiber layers 15 are alternately arranged side by side on the liquid impermeable resin film 11.
Further, in the above step, the hot melt adhesive 81 and the cellulose nanofiber layer 15 are provided in the adhesive region 82 of the liquid impermeable resin film 11, and then the liquid impermeable resin film 11 and the exterior nonwoven fabric 12 are adhered to each other. It was a process to make it. However, as another step, a hot melt adhesive 81 and a cellulose nanofiber layer 15 are provided in the adhesive region 82 of the exterior nonwoven fabric 12, and then the exterior nonwoven fabric 12 and the liquid-impermeable resin film 11 are adhered to each other. You can also do it.

The invention made by the inventor has been described above as an embodiment. However, the invention should not be limited by the description or drawings showing the present embodiment. Other examples and the like performed by those skilled in the art based on the present embodiment are included in the present invention.

<Effect confirmation test>
The effect confirmation test of the cellulose nanofiber layer 15 was carried out. The specifications of the absorber 56, the liquid-impermeable resin film 11, the exterior nonwoven fabric 12, and the cellulose nanofibers used in this effect confirmation test are as follows.

The absorber 56 is a uniform mixture of pulp fibers and highly absorbent polymer particles, and contains 180 g / m ² of pulp fibers and 220 g / m ² of highly absorbent polymer particles.

The highly absorbent polymer particles have a water absorption rate of 33 g / g, a water absorption rate of 35 seconds, and a gel strength of 3800 Pa, and are sieved using a standard sieve (JIS Z8801-1: 2006) of 500 μm (shaking for 5 minutes). And the percentage of particles remaining on the 500 μm standard sieve when sifting (shaking for 5 minutes) using a 180 μm standard sieve (JIS Z8801-1: 2006) for the particles falling under the sieve by this sieving. Was 18% by weight, and the proportion of particles remaining on the standard sieve of 180 μm was 80% by weight.

As the liquid-impermeable resin film 11, a moisture-permeable polyethylene film having a basis weight of 18 g / m ² was used. The moisture permeability of the liquid-impermeable resin film 11 (method of temperature / humidity condition B of JIS Z 0208 (temperature 40 ° C. humidity 90% condition)) was 9000 g / m 2.24 h in the effect confirmation test 1, and the effect confirmation test ² Then, it was set to 9000 g / ^m 2.24 h and 10000 g / ^m 2.24 h.

Further, as the exterior nonwoven fabric 12, an air-through nonwoven fabric having a basis weight of 20 g / m ² using a composite fiber (fineness 2.0 dtex) having a core sheath structure of polyethylene (sheath) and polyethylene terephthalate (core) was used.

The cellulose nanofiber used in this test is 100% NBKP cellulose nanofiber. Further, cellulose nanofibers having an average fiber width (median diameter) of 49 nm were used. This cellulose nanofiber was obtained by subjecting NBKP to a refiner treatment for rough defibration, and then treating the NBKP four times with a high-pressure homogenizer to defibrate the fiber. Further, this average fiber width is measured by the above-mentioned method for measuring the average fiber width of cellulose nanofibers.

The following sample diapers were prepared, and the concentration of methyl mercaptan, which is the main component of the odor of excrement, was measured. The purpose of this test is to confirm how much the concentration of methyl mercaptan is reduced in a diaper provided with the cellulose nanofiber layer 15.

(Sample diaper)
The diaper samples used in this test are as follows.
There are 9 samples from S1 to S9. As shown in Table 1, the samples S1 to S6 have a moisture permeability of 9000 g / ^m 2.24 h, and the samples S7 to S9 have a moisture permeability of 10000 g / ^m 2.24 h. The basis weight of the cellulose nanofiber layer 15 was adjusted between 0.3 and 4.5 g / m ² . The cellulose nanofiber layer 15 was provided on the liquid-impermeable resin film 11 in a striped pattern having a coating width of 5 mm and a coating interval of 5 mm, and the hot melt adhesive 81 was applied only to the non-coated portion of the cellulose nanofiber layer 15. Cellulose nanofibers have NBKP of 100% and an average fiber width (median diameter) of 49 nm.

(Test operation)
An odorous liquid was prepared by dissolving methyl mercaptan in water so that the concentration (mass / volume) was 0.5%. 50 mL of this odorous liquid was injected into the center of the absorber 56 on the inner surface of the diaper. The diaper was placed in a gas-impermeable bag, sealed and allowed to stand. After 0 hours, 4 hours and 24 hours after injecting the odorous liquid, the methyl mercaptan concentration (ppm) in the bag was measured by the detector tube method (JIS K 0804: 2014 detector tube type gas measuring instrument). .. The detector tube method is a method in which 500 ml of a gas to be tested is sucked in by a detector tube and the concentration (ppm) of the gas to be tested is measured. The detector tube used was Gastec's detector tube Methyl mercaptan No. 71 and 71H.

(result)
The test results are shown in Table 1. In the table, the basis weight refers to the basis weight (g / m ² ) when the cellulose nanofibers are applied to the liquid-impermeable resin film 11.

Table 1 shows the methyl mercaptan concentration (ppm) and the odor reduction rate (%) of methyl mercaptan measured immediately after injection (after 0 hour), 4 hours and 24 hours after injecting the odorous liquid for the samples S1 to S9. ). In the table, the odor reduction rate (%) is calculated by the following formula.

Here, in the mathematical formula, the concentration of the sample S1 immediately after injection means the concentration of methyl mercaptan measured immediately after injecting the odorous liquid into the center of the absorber 56 for the sample S1.
The concentration of the sample Sm after t hours means the concentration of methyl mercaptan measured after t hours of the sample Sm. m is any of 1 to 9, and t is any of 0, 4, and 24.

Focusing on the odor reduction rate after 4 hours in Table 1, the samples coated with the cellulose nanofibers (S2 to S9) tend to be relatively higher than the samples not coated with the cellulose nanofibers (S1). In particular, the samples 4 to 6 show a particularly high odor reduction rate.

From this result, the coating amount of the cellulose nanofibers is preferably 0.3 g / m ² or more, and more preferably 1.5 g / m ² or more.

<Explanation of terms in the specification>
When the following terms are used in the specification, they have the following meanings unless otherwise specified in the specification.
-The "front-back (vertical) direction" means the direction connecting the ventral side (front side) and the dorsal side (rear side), and the "width direction" means the direction orthogonal to the front-back direction (horizontal direction).

-"Inside" means the one closer to the wearer's skin, and "outside" means the one farther from the wearer's skin. The "inner surface" means the surface of the member closer to the wearer's skin, and the "outer surface" means the surface farther from the wearer's skin.

-The "LD direction" and "WD direction" mean the flow direction (LD direction) in the manufacturing equipment and the lateral direction (WD direction) orthogonal to this, and one of them is the front-rear direction of the product. The other is in the width direction of the product. The LD direction of the nonwoven fabric is the direction of the fiber orientation of the nonwoven fabric. The fiber orientation is the direction along which the fibers of the non-woven fabric are aligned. It can be discriminated by a simple measurement method for determining the orientation direction.

-"Unfolded state" means a state in which the unfolded state is flat without shrinkage or slack.

-"Elongation rate" means a value when the natural length is 100%.

-"Gel strength" is measured as follows. Artificial urine (urea: 2 wt%, sodium chloride: 0.8 wt%, calcium chloride dihydrate: 0.03 wt%, magnesium sulfate heptahydrate: 0.08 wt%, and ion-exchanged water: 97.09 wt%) Add 1.0 g of highly absorbent polymer to 49.0 g and stir with a stirrer. The produced gel is left in a constant temperature and humidity chamber at 40 ° C. × 60% RH for 3 hours, then returned to room temperature, and the gel strength is measured with a card meter (Curdmeter-MAX ME-500 manufactured by I. techno Engineering).

・ "Metsuke" is measured as follows. After pre-drying the sample or test piece, leave it in a test room or device in a standard state (test location: temperature 23 ± 1 ° C., relative humidity 50 ± 2%) to bring it to a constant weight. Pre-drying refers to constant weight of a sample or test piece in an environment with a temperature of 100 ° C. For fibers with an official moisture content of 0.0%, pre-drying does not have to be performed. From the test piece in a constant weight state, a sample having a size of 100 mm × 100 mm is cut out using a sampling template (100 mm × 100 mm). The weight of the sample is measured and multiplied by 100 to calculate the weight per square meter, which is used as a basis weight.

-The "thickness" is automatically measured using an automatic thickness measuring device (KES-G5 handy compression tester) under the conditions of a load of 0.098 N / cm ² and a pressurized area of 2 cm ² .

-"Water absorption" is measured by JIS K7223-1996 "Water absorption test method for highly water-absorbent resin".

-"Water absorption rate" is the "time to the end point" when JIS K7224-1996 "Water absorption rate test method for highly water-absorbent resin" was performed using 2 g of highly absorbent polymer and 50 g of physiological saline. And.

-If there is no description of the environmental conditions in the test or measurement, the test or measurement shall be performed in a test room or device under standard conditions (test location: temperature 23 ± 1 ° C, relative humidity 50 ± 2%). do.

-Unless otherwise specified, the dimensions of each part mean the dimensions in the unfolded state, not in the natural length state.

The present invention can be applied to all disposable diapers such as pants-type disposable diapers and pad-type disposable diapers, in addition to tape-type disposable diapers as in the above example, and also to other worn items such as menstrual napkins. Needless to say, it can be applied.

11 ... Liquid impermeable resin film, 12 ... Exterior non-woven fabric, 13 ... Connecting tape, 13A ... Connecting part, 13B ... Tape body part, 13C ... Tape mounting part, 15 ... Cellulose nanofiber layer, 15A ... Linear adhesive part Width, 20 ... target sheet, 21 ... both ends edge, 30 ... top sheet, 40 ... intermediate sheet, 50 ... absorbent element, 56 ... absorber, 56W ... absorber width, 58 ... packaging sheet, 60 ... rising gather, 62 ... Gather sheet, 81 ... Hot melt adhesive, 81A ... Width of linear adhesive part, 82 ... Adhesive area, B ... Back side part, F ... Ventral part, WD ... Width direction, LD ... Front-back direction.

Claims (5)

The first sheet and
A second sheet having a portion overlapping one surface of the first sheet,
In a disposable wearable article having an adhesive region to which the first sheet and the second sheet are adhered,
A plurality of first adhesive portions bonded via a hot melt adhesive are provided in the adhesive region at intervals, and are bonded between adjacent first adhesive portions via a cellulose nanofiber layer. A second adhesive part is provided,
Disposable wear goods characterized by that. It is a worn article having an absorber, a liquid-impermeable resin film covering the outside of the absorber, and an exterior nonwoven fabric covering the outside of the liquid-impermeable resin film.
One of the first sheet and the second sheet is the liquid-impermeable resin film, and the other is the exterior nonwoven fabric.
The first adhesive portion has a striped portion in which linear adhesive portions continuous in the front-rear direction are lined up at intervals in the width direction.
The second adhesive portion has a striped portion in which linear adhesive portions continuous in the front-rear direction are lined up at intervals in the width direction.
A part or all of the linear adhesive portion of the second adhesive portion is arranged between the adjacent linear adhesive portions in the first adhesive portion.
The disposable wearable article according to claim 1. The width of the linear adhesive portion of the first adhesive portion is 1 to 20 mm, the interval in the width direction of the linear adhesive portion of the first adhesive portion is 1 to 20 mm, and the linear adhesive portion of the first adhesive portion is linearly adhered. The part consists of 1-20 g / m ² hot melt adhesive
The width of the linear adhesive portion of the second adhesive portion is 1 to 20 mm, the interval in the width direction of the linear adhesive portion of the second adhesive portion is 1 to 20 mm, and the linear adhesive portion of the second adhesive portion is linearly adhered. The moiety is made of the cellulose nanofibers of 0.3-15.0 g / m ² .
The disposable wearable article according to claim 2. The second adhesive portion is provided only in a range overlapping with the absorber.
The disposable wearable article according to claim 2 or 3. A part or the whole of the second adhesive portion is not covered with the hot melt adhesive.
The disposable wearable article according to any one of claims 1 to 4, characterized in that.

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