JP7097208B2 - Absorbent article and method for manufacturing absorbent article - Google Patents

Description

The present invention relates to an absorbent article and a method for producing an absorbent article.

As absorbent articles, disposable diapers in the form of pad type, tape type, pants type and the like, as well as menstrual napkins are known. Such an absorbent article generally includes an upper layer sheet including a liquid permeable top sheet, a lower layer sheet including a liquid permeable back sheet, and an absorbent layer arranged between the two. It has become. Further, the absorbent layer is arranged in the upper sheet and the lower sheet in a plan view, and the upper sheet and the lower sheet are bonded to each other around the absorbent layer.

In absorbent articles, most of the upper layer sheets and lower layer sheets are porous sheets having breathability such as non-woven fabrics and poly sheets. Therefore, when an adhesive is used when bonding the upper layer sheet and the lower layer sheet, the adhesive may fall into the holes or strike through depending on the type and amount of the adhesive used. As a result, the adhesive area becomes small, and sufficient adhesive strength may not be obtained. Therefore, if a large force is applied while the absorbent article is attached, the adhesion between the upper layer sheet and the lower layer sheet may be damaged, and the body fluid may leak sideways from the absorbent layer.

By the way, in the field of porous sheets, improvement of various properties such as strength is being studied. For example, in Patent Document 1, two different compositions, that is, a sheet-like material formed into a multi-row sheet in which (a) composition and (b) composition are alternately arranged, is subjected to a stretching treatment to be porous. The sex sheet is disclosed. It is described that such a porous sheet is excellent in breathability, moisture permeability, and adhesiveness, and that such a sheet can be suitably used for disposable diapers and the like.

Japanese Patent No. 3157580

In the technique disclosed in Patent Document 1, two different compositions are prepared and extruded in multiple rows to produce a porous sheet. That is, the technique disclosed in Patent Document 1 changes the structure of the porous sheet itself. Therefore, when the sheet disclosed in Patent Document 1 is used for an absorbent article, the production of the sheet itself, and eventually the production of the absorbent article becomes complicated, and the cost may increase.

In view of the above points, it is an object of the present invention to provide an absorbent article capable of preventing leakage by improving the adhesive strength between the upper layer sheet and the lower layer sheet easily and at low cost.

A first aspect of the present invention comprises a porous upper layer sheet, an impermeable and porous lower layer sheet, and an absorber layer disposed between the upper layer sheet and the lower layer sheet. An absorbent article having a predetermined length in the front-rear direction and a predetermined width in the width direction orthogonal to the front-rear direction, and at least one of the upper layer sheet and the lower layer sheet is subjected to hole closing treatment. It has a pore-blocking region, and the pore-blocking region extends in the anteroposterior direction at least outside the width direction of the absorber layer, and in at least a part of the pore-blocking region, the upper layer sheet and the lower layer sheet Are bonded together with an adhesive.

According to the first aspect, at least one of the upper layer sheet and the lower layer sheet has a hole closing region, and the upper layer sheet and the lower layer sheet are adhered to each other in at least a part of the hole closing region. It is pasted together by. Since the hole closing treatment is a treatment for forming a non-ventilated portion by closing the pores of the upper layer sheet and / or the lower layer sheet which are porous, the holes of the sheet subjected to the hole closing treatment are at least partially closed. Is done. Therefore, in the hole closing region, it is possible to increase the adhesive area when adhering with the adhesive, and it is possible to improve the adhesive strength between the sheets in the portion where the upper layer sheet and the lower layer sheet are bonded with the adhesive. .. As described above, according to this aspect, it is not necessary to change the configuration of the sheet itself, and by applying the treatment to the existing sheet, it is possible to improve the adhesive strength easily and at low cost.

Further, the hole closing region extends in the anteroposterior direction at least outward in the width direction of the absorber layer. The outer part of the absorber layer in the width direction (that is, the side part of the absorbent article) is a part where a force is easily applied and the adhesive strength is relatively lowered, but the hole closing region is extended in the front-rear direction. Thereby, the adhesive strength between the upper layer sheet and the lower layer sheet in the portion can be improved. This makes it possible to prevent the body fluid once absorbed by the absorber layer from leaking to the side.

In the second aspect of the present invention, the adhesive is a hot melt adhesive.

According to the second aspect, since the hot melt adhesive is used as the adhesive, the absorbent article can be safely manufactured and used, and relatively high adhesive strength can be imparted. Further, in this embodiment, by having the pore closing region, high adhesive strength can be obtained even if a hot melt adhesive is used.

In the third aspect, the pore closing treatment is applied to the lower layer sheet, and the lower layer sheet contains a poly sheet.

According to the third aspect of the present invention, the hole closing treatment is applied to the lower layer sheet which is a poly sheet. Since the porosity of the policy is fine, the pores can be satisfactorily closed by the pore closing treatment. Therefore, according to this aspect, the effect of improving the adhesive strength between the sheets can be further exhibited.

In the fourth aspect of the present invention, the hole closing process is a process of applying ink by printing, or a process of applying heat or ultrasonic waves.

According to the fourth aspect, the pore closing treatment is by applying ink or applying heat or ultrasonic waves. Since these treatments are often used in the manufacturing process of the absorbent article, it is possible to form the hole closing region relatively easily without the need to newly introduce an apparatus.

In the fifth aspect of the present invention, the hole closure region includes a continuously extending portion with an area of 100 mm ² or more.

According to the fifth aspect, since the hole closing region includes a continuously extending portion having a predetermined area, it is possible to further improve the adhesive strength.

In the sixth aspect of the present invention, a liquid-permeable and porous upper layer sheet, a liquid-impermeable and porous lower layer sheet, and an absorber disposed between the upper layer sheet and the lower layer sheet. A method for manufacturing an absorbent article having a layer, having a predetermined length in the front-rear direction, and having a predetermined width in the width direction orthogonal to the front-rear direction, wherein at least one of the upper layer sheet and the lower layer sheet. Is subjected to a hole closing treatment to form a hole closing region extending in the anteroposterior direction at least outside the width direction of the absorber layer, and the upper sheet and the lower layer sheet are at least partially formed in the hole closing region. Includes bonding and with an adhesive.

According to the sixth aspect, it is possible to provide an absorbent article having the same effect as that of the first aspect.

According to one aspect of the present invention, it is possible to provide an absorbent article capable of preventing leakage by improving the adhesive strength between the upper layer sheet and the lower layer sheet easily and at low cost.

It is a top view of the absorbent article by 1st Embodiment of this invention. It is a schematic diagram of the cross section of the line II of FIG. It is a partially enlarged view of FIG. It is a top view of the absorbent article by 2nd Embodiment of this invention. It is a schematic diagram of the cross section of line II-II of FIG. It is a top view of the absorbent article by the 3rd Embodiment of this invention. It is a top view of the absorbent article according to 4th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing, unless otherwise specified, the same or corresponding configurations may be designated by the same reference numerals and description thereof may be omitted.

First, the basic structure of the absorbent article according to the embodiment of the present invention will be described. FIG. 1 shows a plan view of the absorbent article 100 according to the first embodiment of the present invention. The first embodiment is a pad-type disposable diaper (urine absorbing pad or absorbent pad). Further, FIG. 2 schematically shows a sectional view taken along line I-I of FIG.

The absorbent article 100 has a predetermined length in the first direction (front-back direction or vertical direction) D1 in a plan view, and is predetermined in the second direction (width direction or lateral direction) D2 orthogonal to the first direction D1. Has a width of. In the form of FIG. 1, the width of the absorbent article 100 is shorter than the length, that is, it has an elongated shape as a whole, but the overall shape of the absorbent article 100 is not limited to the one shown in the figure.

The length (total length) of the absorbent article 100 in the front-rear direction D1 can be about 350 to 700 mm, and the length (total width) in the width direction D2 can be about 130 to 400 mm. The shape of the absorbent article 100 can be axisymmetric with the center line (center line in the anteroposterior direction) CL extending in the anteroposterior direction D1 as a line of symmetry, but it does not necessarily have to be axisymmetric. Further, the configuration of the absorbent article 100 (size, shape, arrangement, etc. of each element) may be line-symmetrical, but it does not have to be line-symmetrical as in the shape of the absorbent article 100.

The absorbent article 100 has a crotch-corresponding region RC. The "groin corresponding area" means a part corresponding to the crotch (inseam) of the body at the time of use. The crotch-corresponding region RC may be, for example, a range from the center of the absorbent article 100 in the anteroposterior direction or its vicinity to a predetermined position in front of the absorbent article 100, or may be a predetermined range in the center of the absorbent article in the anteroposterior direction D1. .. In the form of FIG. 1, the absorbent article 100 is formed with a constricted portion having a narrow width, but the region where the constricted portion is formed or a part thereof is a crotch corresponding region RC. Often, the region where the constricted portion is formed may be a part of the crotch-corresponding region RC. The length of the crotch-corresponding region RC in the front-rear direction D1 may be about 10 to 150 mm.

Further, the region adjacent to the front of the crotch-corresponding region RC and up to the front end of the absorbent article 100 is the anterior region RF, adjacent to the rear of the crotch-corresponding region RC, and the region up to the rear end of the absorbent article 100. Is the rear region RR. When mounted, the anterior region RF is applied to the ventral side of the wearer and the posterior region RR is applied to the dorsal side of the wearer.

As described above, the plan-view shape of the absorbent article 100 does not have a portion (constricted portion) whose width is narrower than that of the front-rear region, but has a rectangular shape or the like whose width is constant in the front-rear direction D1. , Other shapes are also possible.

As shown in FIGS. 1 and 2, the absorbent article 100 includes a top sheet (also referred to as a front sheet) 22 arranged on the upper side and a back sheet (also referred to as a back sheet) 21 arranged on the lower side. It has an absorber layer 30 arranged between the sheets 21 and 22. Further, on the side portion (outer end portion in the width direction D2) of the absorbent article 100, a gather sheet 24 that extends in the front-rear direction D1 so as to partially overlap the top sheet 22 and can form an upright gather. 24 may be arranged. Further, an exterior sheet 23 may be provided under the back sheet 21.

In the present embodiment, the top sheet 22 and the gather sheet 24 are arranged on the upper side of the absorber layer 30, and the back sheet 21 and the exterior sheet 23 are arranged on the lower side of the absorber layer 30. In the present specification, the sheet arranged on the upper side (skin facing surface side) of the absorbent layer may be referred to as the upper layer sheet 20A. Further, the sheet arranged below the absorber layer 30 (outer surface side) may be referred to as a lower layer sheet 20B. The terms upper layer sheet 20A and lower layer sheet 20B may be used for each sheet, or may be used as a general term for the plurality of sheets when a plurality of sheets exist.

When the absorbent article 100 is attached, the top sheet 22 side is the skin side (skin facing surface side), and the lower layer sheet 21 side is the side fixed to the outer (outer diaper), underwear, etc. (outer surface side). Become.

The back sheet 21 is impermeable and has a function of preventing the body fluid that has passed through the top sheet 22 and the absorbent layer 30 from being discharged to the outer or underwear side. As the back sheet 21, a porous (microporous) sheet having impermeable liquid property and high breathability and moisture permeability can be used. More specifically, the backsheet 21 is preferably a polysheet (polymer film), for example, a sheet mainly containing an olefin resin such as polyethylene or polypropylene. Such a polysheet can be produced, for example, by melting and kneading an inorganic filler or the like in a resin to form a sheet, and then stretching the sheet in a uniaxial or biaxial direction. The back sheet 21 may be a stack of two or more of the above-mentioned sheets. If the breathability of the absorbent article 100 is not so required, the back sheet 21 can be a non-breathable (non-porous) sheet.

In this embodiment, as shown in FIG. 1, the backsheet 21 has the same shape and size as the absorbent article 100. Further, the size of the back sheet 21 is larger than that of the absorber layer 30. That is, the back sheet 21 is arranged so as to protrude from the entire periphery of the absorber layer 30 in a plan view.

Further, although the exterior sheet 23 is arranged on the outer surface of the back sheet 21, the back sheet 21 may be configured to be the outermost surface of the absorbent article 100 without providing the exterior sheet 23. As the exterior sheet 23, it is preferable to use a non-woven fabric or the like from the viewpoint of improving the feel of the outer surface of the absorbent article 100 and from the viewpoint of being able to absorb the body fluid to some extent even when the body fluid is transferred to the outer surface of the absorbent article 100. ..

The top sheet 22 has a function that the top sheet 22 is liquid permeable and the discharged body fluid is rapidly transferred to the absorber layer 30 arranged below the top sheet 22. The top sheet 22 may be a non-woven fabric, a polysheet having an opening capable of transferring body fluid to the absorbent layer, or the like. That is, a porous sheet can be used as the top sheet 22. When the top sheet 22 is a non-woven fabric, the material fibers include olefin-based fibers such as polyethylene and polypropylene, synthetic fibers such as polyester-based and amide-based fibers, recycled fibers such as rayon and cupra, and natural fibers such as cotton. Can be done. The top sheet 22 may also be a stack of two or more of the above-mentioned sheets.

In the present embodiment, the top sheet 22 does not extend to the end of the absorbent layer 30 in the width direction D2, but only partially covers the absorbent layer 30. The portion of the absorbent layer 30 that is not covered by the top sheet 22 is covered by the gather sheets 24, 24 described later. However, regardless of the presence or absence of the gather sheets 24 and 24, the top sheet 22 covers the entire absorbent layer 30 and has a size and shape protruding from the entire periphery of the absorbent layer 30 in a plan view. May be.

An intermediate sheet (second sheet) can be interposed between the top sheet 22 and the absorber layer 30. By providing the intermediate sheet, it is possible to prevent the body fluid absorbed by the absorber layer 30 from retreating. Therefore, as the intermediate sheet, it is preferable to use a material having low water retention and high liquid permeability, for example, various non-woven fabrics, mesh films and the like.

As the gather sheets 24 and 24, porous sheets such as non-woven fabrics and poly sheets can be used. From the viewpoint of good touch to the skin, a non-woven fabric treated with water repellent treatment such as silicone is preferably used.

An elastic member fixed in an extended state along the front-rear direction D1 may be provided at the inner end of each cather sheet 24 in the width direction D2. This elastic member may be made of styrene-based rubber, olefin-based rubber, urethane-based rubber, ester-based rubber, or the like formed in a thread-like shape, a string-like shape, a strip-like shape, or the like.

The front and rear ends of the gather sheet 24 are directly below the sheet (top sheet 22, the packaging sheet 26, and the back sheet 21), and the side portions of the gather sheet 24 are directly below the gather sheet 24 along the front-rear direction D1. Sheets (top sheet 22, packaging sheet 26, and back sheet 21) are bonded to each other. Since the elastic member as described above is provided, the portion where the gather sheet 24 is not joined (the region inside the gather sheet 24 in the width direction D2 and excluding both ends thereof) is formed. It can be a three-dimensional gather G, G standing on the skin facing surface side (top sheet side) of the absorbent article 100. The gathers G and G can prevent the leakage of body fluid to the side.

The absorber layer 30 contains fibers or filaments. The absorbent layer 30 may be, for example, a stack of pulp fibers, an aggregate of filaments such as cellulose acetate, a non-woven fabric, or the like, and if necessary, a highly absorbent polymer such as particles may be mixed and fixed. Can be used.

The fiber basis weight and the basis weight of the highly absorbent polymer in the absorbent layer 30 can be appropriately determined, but the fiber basis weight is preferably about 100 to 700 g / m ² , and when the absorbent polymer is contained, the basis weight is 50. It is preferably about 550 g / m ² .

The absorbent layer 30 may be entirely or partially wrapped by a packaging sheet 26 such as a non-woven fabric or crepe paper. As described above, when the absorbent layer 30 mixes the highly absorbent polymer particles, it is preferable to use the packaging sheet 26 for the purpose of preventing the particles from spilling. When the absorbent layer 30 is composed of a plurality of layers, each layer may be wrapped by a packaging sheet, or the packaging sheet may be sandwiched between the layers. The packaging sheet 26 may be uncolored (that is, white) or may be colored. The color can be a color that can make the color of the discharged body fluid inconspicuous, for example, a color close to the color of the body fluid, a complementary color of the color of the body fluid, or a color close to the color.

In the form of FIG. 1, the absorbent layer 30 has an elongated shape as a whole, similar to the absorbent article 100. More specifically, the plan view shape of the absorber layer 30 has a constricted portion, similar to the overall plan view shape of the absorbent article 100. However, the plan view shape of the absorber layer 30 may be, for example, a rectangular shape having no constricted portion having a constant width over the front-rear direction D1 regardless of the plan view shape of the absorbent article 100.

Since the absorbent article is made by laminating layered components, it has a portion in which the components are bonded to each other over a predetermined area. Among such bonded portions, a portion in which the upper layer sheet and the lower layer sheet are laminated is particularly formed around the absorber layer (a region outside the absorber layer in a plan view and without the absorber layer). From the viewpoint of confining the absorbent layer and preventing leakage of the body fluid once absorbed by the absorbent layer, it is preferable to increase the adhesive strength.

Here, in the absorbent article, as described above, a porous sheet is often used for both the upper layer sheet and the lower layer sheet. In addition, an adhesive is often used for bonding. Therefore, when an adhesive is applied to the surface of a sheet and the sheets are bonded together, the adhesive may be porously dropped or strike through depending on the type and amount of the adhesive, the bonding method, and the like. That is, the adhesive layer cannot be uniformly formed on the coated surface, and the adhesive area may become small. Therefore, when the absorbent article is attached or when the absorbent article is deformed with a large force during attachment, the adhesion between the upper layer sheet and the lower layer sheet may be peeled off. In that case, the body fluid absorbed by the absorber layer may leak to the outside through between the upper layer sheet and the lower layer sheet.

On the other hand, in the present embodiment, a hole closing region in which the hole closing treatment is applied is formed on either one of the upper layer sheet and the lower layer sheet. The pore closing treatment is a treatment for closing (crushing) the porosity of the porous sheet. Then, in the hole closing region where the hole closing treatment has been performed, the adhesive can be uniformly applied on the sheet surface (adhesive surface) to be bonded by adhering the upper layer sheet and the lower layer sheet with an adhesive. Alternatively, it is possible to prevent the adhesive from strike-through and secure a sufficient amount of adhesive on the adhesive surface. This makes it possible to improve the adhesive strength between the upper layer sheet and the lower layer sheet and prevent leakage of body fluids and the like.

The hole closing treatment may be, for example, a treatment (printing) in which ink is applied to the surface of the porous sheet. By applying the ink, a layer of ink can be formed on the surface of the sheet, and the porosity can be filled with the ink. Examples of the ink application method include inkjet printing, gravure printing, flexographic printing and the like. When the hole closing treatment is ink application, the ink can be applied in an amount having a thickness of about 3 to 30 μm, preferably about 8 to 15 μm.

Further, the hole closing treatment may be a treatment of applying heat or ultrasonic waves. By this treatment, the shape around the hole can be physically changed by heat or ultrasonic waves, and the hole can be closed.

In any of the hole closing treatments, the treatment can be performed after the upper layer sheet and the lower layer sheet are prepared and before the absorbent article is formed.

In FIG. 1, an example of the range in which the hole closing region 40 is provided is shown by diagonal lines. As shown in the figure, the hole closing region 40 is preferably provided at least around a range in which the absorber layer 30 is arranged in a plan view, that is, in a region outside the edge of the absorber layer 30. .. Further, in the illustrated form, the hole closure region 40 is formed so as to surround the absorber layer 30. That is, it is continuously formed over the entire circumference of the absorber layer 30. As described above, according to the form in which the hole closing region 40 is continuously formed in an annular shape without interruption, the absorbent layer 30 can be sealed with a higher adhesive strength over the entire circumference, and thus the absorbent layer 30 can be sealed from the absorbent layer 30. It is preferable because the leakage of the body fluid to the side can be satisfactorily prevented and the absorber layer 30 can be stabilized at that position.

The hole blockage region 40 does not have to be continuous in an annular shape as described above. For example, the hole closure region 40 can extend outside the width direction D2 of the absorber layer 30 in the anteroposterior direction D1, preferably on both sides. Since the portion outside the width direction D2 of the absorber layer 30 is a place where a large force is applied during mounting and is easily twisted, the hole closing region 40 is extended to at least the outside of the width direction D2 of the absorber layer 30 in the front-rear direction D1. Leakage can be effectively prevented by allowing it to exist.

As shown in the figure, the hole closure region 40 preferably extends in a band shape at the front and rear ends and the side portions. In this case, the width of the band can be about 5 to 50 mm, although it depends on the structure of the absorbent article. The width of the band may vary from place to place and according to the plan view shape of the absorber layer 30.

As shown in FIG. 1, the hole closure region 40 may partially overlap the edge portion of the absorber layer 30 in a plan view. That is, the hole closing region 40 may be formed in the upper layer sheet 20A and / or the lower layer sheet 20B even in the portion overlapping the absorber layer 30. When the hole closing region 40 partially overlaps the edge of the absorber layer 30 in a plan view, the upper layer sheet 20A (gather sheet 24 in this embodiment) and the packaging sheet 26 for wrapping the absorber layer 30 When is adhered with an adhesive, the adhesive strength between the sheets can be improved.

However, the range of the hole closing region 40 that overlaps and extends at the edge of the absorber layer 30 is preferably about 10 mm from the edge of the absorber layer 30. This makes it possible to avoid obstruction of air permeability in the center of the portion where the absorber layer 30 is arranged.

Further, the hole closing region 40 may partially extend adjacent to the edge portion of the absorber layer 30, or may extend at a distance of, for example, about 5 to 50 mm from the edge portion. good. When the hole closing region 40 extends adjacent to the edge portion, it is preferable from the viewpoint that the absorber layer 30 can be sandwiched and fixed between the upper layer sheet 20A and the lower layer sheet 20B. On the other hand, when the hole closing region 40 is separated from the edge portion of the absorber layer 30, it is preferable from the viewpoint of enabling the relative movement of the absorber layer 30 with respect to the sheet and not generating an excessively large stress.

In the illustrated embodiment, the hole obstruction region 40 extends parallel to the width direction D2 at the front and rear ends, and extends parallel to the anteroposterior direction D1 at both sides, but the hole obstruction region. The extending direction of 40 is not limited. The hole closing region 40 may be inclined with respect to the front-rear direction D1 and the width direction D2. Further, the shape may be formed along the edge of the absorber layer 30. That is, when the plan view shape of the absorber layer 30 is constricted as shown in the drawing, for example, the portion extending along the anteroposterior direction D1 of the hole closing region 40 is the width direction D2 along the constricted portion. It may be formed so as to be convex on the side.

The hole closing region 40 extending in the front-rear direction D1 on the side portion of the absorbent article 100 does not necessarily have to be provided from the front end portion to the rear end portion. However, it is preferable that the hole closing region 40 continuously extends from the front end portion to the rear end portion on the side portion because the adhesive strength can be improved. Further, it is preferable that the hole closing region 40 extending in the front-rear direction D1 is provided at least in the crotch corresponding region RC. This is because in the crotch-corresponding region RC, a large force is likely to be applied during wearing, and the adhesion between the sheets may be impaired when the sheet is worn for a long time.

The hole closure region 40 may have a discontinuous portion. However, the larger the continuous portion, the higher the effect of improving the adhesive strength between the sheets. The hole closing region 40 may be formed so that the area of one continuous portion is 100 mm ² or more, preferably 200 mm ² or more, and more preferably 400 mm ² or more.

The hole closing region 40 may be provided at an arbitrary position (including the edge of the absorber layer 30) in the region where the absorber layer 30 is arranged in a plan view. The upper layer sheet 20A is provided with a hole closing region 40 by performing a hole closing treatment at an arbitrary position in the region where the absorber layer 30 is arranged, and the upper layer sheet is provided in a region including at least a part of the hole closing region 40. When an adhesive is applied between 20A (top sheet 22 and / or gather sheet 24 in this embodiment) and the packaging sheet 26 to form an adhesive, between the upper layer sheet 20A and the packaging sheet 26. Adhesive strength can be improved. As a result, the position of the absorbent layer 30 wrapped in the packaging sheet 26 can be fixed between the upper layer sheet 20A and the lower layer sheet 20B, and the absorbent article 100 can be prevented from being twisted. The same effect is obtained when the lower layer sheet 20B (back sheet 21 in this embodiment) is subjected to the hole closing treatment to provide the hole closing area 40 at an arbitrary position in the area where the absorber layer 30 is arranged. Can be obtained.

It is preferable that the hole blocking region 40 in the region where the absorber layer 30 is arranged is not too large in a plan view so as not to impair the air permeability of the region where the absorber layer 30 is arranged. For example, the total area of the hole closing region 40 with respect to the plan view area of 100% of the absorber layer 30 is preferably 20% or less, more preferably 10% or less, and even more preferably 5% or less.

The hole closing treatment may be applied to either the upper layer sheet 20A or the lower layer sheet 20B. Further, it may be applied to both the upper layer sheet 20A and the lower layer sheet 20B. In the first embodiment, the gather sheet 24 and the back sheet 21 are directly bonded to each other at the portion where the absorber layer 30 is not arranged (FIG. 2). In this case, the hole closing treatment may be applied to either the gather sheet 24 or the back sheet 21, or both may be applied.

Further, the hole closing treatment may be applied to either surface of the sheet (upper layer sheet 20A and / or lower layer sheet 20B), or may be applied to both surfaces. It is preferable that the adhesive is applied to the side of the adhesive surface to which the adhesive is applied, but even if the adhesive is applied to the side opposite to the adhesive surface, it is possible to prevent the adhesive from striketing through and falling off, thus improving the adhesive strength. Can be made to.

FIG. 3 shows a partially enlarged view of FIG. FIG. 3 shows a side region of the absorbent article 100. In the illustrated form, the upper surface of the back sheet 21 is subjected to a hole closing treatment. In this embodiment, the pore closing treatment is performed by applying ink to form the ink layer 42. Since the adhesive 52 is applied to the region including the portion of the ink layer 42 and the back sheet 21 and the gather sheet 24 are bonded to each other, the adhesive strength between the two sheets can be improved.

In the form of FIG. 3, the back sheet 21 and the exterior sheet 23 are also bonded by the adhesive 52', but since the back sheet 21 is subjected to the hole closing treatment, the space between the back sheet 21 and the exterior sheet 23 is formed. Adhesive strength can also be improved.

The hole closing region 40 may or may not coincide with the region where the upper layer sheet 20A and the lower layer sheet 20B are bonded (also referred to as a bonding area). Therefore, the hole closing area 40 may be provided beyond the bonding area, or the bonding area may be provided beyond the hole closing area 40. The form of FIG. 3 corresponds to the latter.

When the bonding area is provided beyond the hole closing area 40, the amount of the adhesive applied to the hole closing area 40 and the amount of the adhesive applied to the area not provided with the hole closing area 40 can be changed. can. Since the pore closing region 40 subjected to the pore closing treatment can increase the adhesive strength when an adhesive is used, the amount of the adhesive applied to the pore closing region 40 is applied to the region where the pore closing region 40 is not provided. It can be smaller than the amount of adhesive to be applied. That is, even if the amount of the adhesive used is smaller, the adhesive strength equivalent to that of the conventional structure can be obtained. Therefore, the cost can be reduced, and the flexibility of the article can be maintained even when an adhesive that tends to become hard after curing is used. The amount of the adhesive can be reduced, for example, by reducing the thickness of the adhesive to be applied or by reducing the area of the adhesive to be applied.

In this embodiment, it is preferable to use a hot melt adhesive as the adhesive. A hot-melt adhesive is an adhesive that exerts its adhesive strength by applying heat to melt it (or reduce its viscosity) and applying it to an object, and then solidifying it by cooling. The type of hot melt adhesive is not particularly limited as long as it contains a thermoplastic polymer as a main component. Specific examples of the hot melt adhesive include EVA (ethylene-vinyl acetate copolymer) type, adhesive rubber type (elastomer type), olefin type, polyester / polyamide type and the like.

When a hot melt adhesive is used as the adhesive, the adhesive is applied in a low viscosity state at the time of manufacturing, so that the adhesive seeps out from the back side of the coated surface and adheres to the manufacturing equipment, or the adhesive is not desired. It sometimes adhered to the part. However, according to this embodiment, such an inconvenience can be eliminated by providing the hole closing region.

In this embodiment, the hot melt adhesive can be applied by a coater method, a curtain spray method, a spiral method, a spray method, or the like. The adhesive can be usually applied in an amount of 0.5 g / m ² or more, preferably 1.0 to 10.0 g / m ² .

In the method of manufacturing the absorbent article 100 according to the present embodiment, at least one of the gather sheet 24 (upper layer sheet 20A) and the back sheet 21 (lower layer sheet 20B) is subjected to a hole closing treatment, and at least the width of the absorbent layer 30 is wide. The step of forming the hole closing region 40 extending in the front-rear direction D1 on the outside of the direction D2 and the gather sheet 24 (upper layer sheet 20A) and the back sheet 21 (lower layer sheet 20B) are adhered to each other at least partially in the hole closing region 40. It includes a step of bonding with the agent 52. In this case, the place where the adhesive 52 is provided may be a region including all or a part of the hole closing region 40. That is, the hole closing region 40 and the bonded portion may at least partially overlap each other. Then, the adhesive strength between the sheets can be improved in the overlapped portion and the peripheral portion thereof.

The area occupied by the hole closing region 40 in the bonded portion (the portion where the adhesive is provided) in the region without the absorber layer 30 (the region around the absorber layer 30) in a plan view is the region without the absorber layer 30. It can be 60% or more, preferably 80% or more, more preferably 90%, still more preferably 95% or more with respect to 100% of the area of the bonded portion.

When ink application (printing) is used as the hole closing process for forming the hole closing region 40, a design, a cautionary note, or the like can be printed. As a result, it is possible to improve the adhesive strength, and it is also useful for improving aesthetics and calling attention. In that case, the part that requires design and cautionary notes is first determined, and printing is applied to that part on the upper layer sheet 20A and / or the lower layer sheet 20B, and the area overlapping the printed part is printed. Adhesives can also be applied. Further, it is also possible to detect an image of the printed portion (hole closed area) by using an image processing device or the like and automatically determine the portion to which the adhesive is applied.

Even when heat application or ultrasonic wave application is used as the hole closure treatment, the color of the hole closure treatment portion changes with respect to the untreated portion, so that the processed portion (hole closure region) can be image-detected. ..

FIG. 4 shows the absorbent article 200 according to the second embodiment of the present invention. Further, FIG. 5 shows a schematic view of the II-II cross section of FIG. The second embodiment includes the upper layer sheet 20A, the lower layer sheet 20B, and the absorbent layer 30 arranged between the two sheets, as in the first embodiment, but the stacking relationship of the sheets is different.

As shown in FIGS. 4 and 5, in the absorbent article 200, the absorbent layer 30 wrapped in the packaging sheet 26 is arranged on the back sheet 221 and the top sheet 222 is arranged on the absorbent layer 30. The top sheet 222 is provided so as to cover the absorber layer 30 in the front-rear direction D1 and the width direction D2, that is, to protrude from the region where the absorber layer 30 is arranged.

In the present embodiment, the back sheet 221 has a size that exceeds both ends of the top sheet 222 in the width direction D2, and the portion of the back sheet 221 that exceeds both ends of the top sheet in the width direction D2 is formed. It is folded back to the upper side. The folded portion (folded portion) 221a of the back sheet 22 is arranged on the top sheet 222 (FIG. 5).

Further, in the present embodiment, gather sheets 224 and 224 are provided on both sides of the absorbent article 200 along the front-rear direction D1. The gather sheet 224 is arranged on the folded portion 221a of the top sheet 222 and the back sheet. Similar to the first embodiment, the front and rear ends of the gather sheet 224 and 224 may be bonded to the sheet immediately below the gather sheet 224 and 224. By incorporating an elastic member into the inner end of the gather sheet 224 and 224 in the width direction D2, the unbonded portions can be designated as gathers G and G.

In the present embodiment, the upper layer sheet 220A includes a gather sheet 224, a top sheet 222, and a folded portion 221a of the back sheet 221, and the lower layer sheet 220B includes a back sheet 221. Therefore, in the present embodiment, the top sheet 222 and the back sheet 221 are bonded to each other by the adhesive 252 around the absorber layer 30. In this case as well, the adhesive strength of the portion can be improved by subjecting either or both of the top sheet 222 and the back sheet 221 to the hole closing treatment.

In the illustrated embodiment, the top sheet 222 and the folded portion 221a of the back sheet 221 are bonded to each other by the adhesive 352'(FIG. 5). In this case, the adhesive strength between the two sheets can be improved by subjecting the folded-back portion 221a of the top sheet 222 and / or the back sheet 221 to a hole closing treatment. Further, the folded portion 221a of the back sheet 221 and the gather sheet 224 are bonded to each other by the adhesive 252'' (FIG. 5). In this case, the adhesive strength between the two sheets can be improved by subjecting the folded-back portion 221a and / or the gather sheet 224 of the back sheet 221 to a hole closing treatment.

As shown in FIG. 4, the hole blocking region 240, which is a region in which at least one of the top sheet 222 and the back sheet 221 (at least one of the upper layer sheet 220A and the lower layer sheet 220B) is subjected to the hole closing treatment, is the absorbent article 200. At the end of the width direction D2, it extends along the front-rear direction D1. The arrangement of the hole blocking region 240 is the same as that described in the first embodiment. Further, the method of forming the hole closing region 240 and the like are the same as those described in the first embodiment.

The specific embodiment has been described in detail using a pad-type disposable diaper as an example, but this embodiment can be applied to other forms of disposable diapers such as tape type and pants type, as well as to menstrual napkins. can.

FIG. 6 shows a plan view of the absorbent article 300 according to the third embodiment. The absorbent article 300 is a view of a pants-type disposable diaper in a deployed state as viewed from the side facing the skin. In FIG. 6, a detailed configuration is omitted in order to explain the embodiment of the present invention.

As shown in FIG. 6, the absorbent article 300 has an exterior body 328 that integrally constitutes the front body and the rear view, and an interior body that is fixed to the skin facing surface side of the exterior body 328 from the front body to the rear view. It has 310 and. The interior body 310 includes a top sheet 322 arranged on the side facing the skin, a back sheet (not shown) arranged on the side of the exterior body 328, and an absorber layer 230 arranged on both sheets. There is.

In the interior body 310, in the portion where the absorber layer 330 is not arranged, the top sheet (upper layer sheet) arranged on the upper side of the absorber layer 330 and the back sheet 321 arranged on the lower side of the absorber layer 330. (Lower layer sheet) can be bonded with an adhesive. Then, as shown in FIG. 6, it is possible to form a hole closing region 340 in which at least one of the top sheet 322 and the back sheet 321 is subjected to the hole closing treatment. The hole closure region 340 partially overlaps the edge of the absorber layer 430 in a plan view, but is mainly arranged outside the absorber layer 330 (a portion without the absorber layer 330). As a result, the strength of the bonding is improved, and the air permeability of the absorbent layer 330 can be ensured.

Further, the exterior body 328 and the interior body 310 may also be bonded with an adhesive. Specifically, the exterior body 328 and the sheet arranged on the exterior body 328 side of the interior body 310, that is, the back sheet are bonded to each other. Therefore, by applying the hole closing treatment to at least one of the exterior body 328 and the back sheet to form the hole closing region, the adhesive strength between the exterior body 328 and the interior body 310 (the adhesive strength between the exterior body 328 and the back sheet). Can be improved.

FIG. 7 shows a plan view of the absorbent article 400 according to the fourth embodiment. The absorbent article 400 is a view of a tape-type disposable diaper viewed from the side facing the skin. In FIG. 7, a detailed configuration is omitted in order to explain the embodiment of the present invention.

As shown in FIG. 7, the absorbent article 400 includes a top sheet 422, a back sheet (not shown), and an absorbent layer 430 disposed between the two sheets. Further, gather sheets 424 and 424 for forming the three-dimensional gathers G and G are provided on the side portion along the front-rear direction D1. Further, on the back side of the absorbent article 400, a fastening tape 470 is provided on the back seat side.

In the area on the side of the absorbent article 400 where the absorber layer 430 is not arranged, the gather sheet 424 or the top sheet 422 (upper layer sheet) and the back sheet (lower layer sheet) may be bonded to each other. Then, a hole closing region 440 in which the hole closing treatment is applied to either the upper layer sheet or the lower layer sheet can be formed. As a result, the strength of the bonding between the upper layer sheet and the lower layer sheet can be improved, and the air permeability in the region where the absorbent layer 430 is arranged can be ensured.

Hole closing treatment in FIG. 6 (third embodiment), composition of hole closing area 340, configuration of other elements, and hole closing treatment in FIG. 7 (fourth embodiment), configuration of hole closing region 440, and others. Unless otherwise specified, the configuration of each element may be the same as that described in the first embodiment.

20A, 220A Upper sheet 20B, 220B Lower sheet 21, 221 Back sheet 221a Folded part of back sheet 22, 222, 322, 422 Top sheet 24, 224, 424 Gather sheet 26 Packaging sheet 30, 330, 430 Absorber layer 40, 240, 340, 440 Pore closure area 42 Ink layer 52, 52', 252, 252', 252'' Adhesive 100, 200, 300, 400 Absorbent article 310 Interior body 470 Fastening tape CL Front-back center line (1st Centerline along direction D1)
D1 Front-back direction (first direction)
D2 width direction (second direction)
G gather G'gather forming part RC crotch correspondence area RF front area RR rear area

Claims (7)

It is provided with a porous upper layer sheet, a liquid-impermeable and porous lower layer sheet, and an absorber layer arranged between the upper layer sheet and the lower layer sheet, and has a predetermined length in the front-rear direction. However, it is an absorbent article having a predetermined width in the width direction orthogonal to the front-back direction.
At least one of the upper layer sheet and the lower layer sheet has a hole closing region that has been subjected to a hole closing treatment.
The hole closure region extends in the anteroposterior direction at least outside the width direction of the absorber layer.
In at least a part of the hole closing region, the upper layer sheet and the lower layer sheet are bonded to each other by an adhesive.
The hole closure region is continuously formed in a ring shape over the entire circumference of the absorber layer in a plan view, and at least partially overlaps with the edge portion of the absorber layer, and the overlapped portion is the absorption. Absorbent article within a range of 10 mm or less from the edge of the body layer . The absorbent article according to claim 1, wherein the adhesive is a hot melt adhesive. The absorbent article according to claim 1 or 2, wherein the hole closing treatment is applied to the lower layer sheet, and the lower layer sheet contains a poly sheet. The absorbent article according to any one of claims 1 to 3, wherein the hole closing treatment is a treatment of applying ink by printing or a treatment of applying heat or ultrasonic waves. The absorbent article according to any one of claims 1 to 4, wherein the hole closing region includes a portion continuously extending over an area of 100 mm ² or more. The absorbent article according to any one of claims 1 to 5, wherein the total area of the hole closing region is 20% or less with respect to 100% of the plan view area of the absorbent layer. It is provided with a liquid-permeable and porous upper layer sheet, a liquid-permeable and porous lower layer sheet, and an absorber layer arranged between the upper layer sheet and the lower layer sheet, and is predetermined in the front-rear direction. A method for manufacturing an absorbent article having a predetermined width in the width direction orthogonal to the front-rear direction.
At least one of the upper layer sheet and the lower layer sheet is subjected to a hole closing treatment, and at least the hole closing region extending in the anteroposterior direction to the outside of the absorber layer in the width direction is the entire surface of the absorber layer in a plan view. It is formed so as to be continuous in a ring shape over the circumference and at least partially overlap with the edge of the absorber layer so that the overlapped portion is within a range of 10 mm or less from the edge of the absorber layer .
A method for producing an absorbent article, which comprises, at least partially, adhering the upper layer sheet and the lower layer sheet with an adhesive in the hole closing region.

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