JP4739608B2 - Absorbent laminate for disposable absorbent article and disposable absorbent article provided with the absorbent laminate - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an absorbent laminate for a disposable absorbent article such as a disposable diaper, and more specifically, it is effectively worn according to the wearer's body shape and movement, and is worn even with a separate urine collecting pad. The present invention relates to an absorbent laminate and a disposable absorbent article that exhibit a leak prevention effect without giving a feeling of stiffness to a person, and can suppress leakage of effluent such as urine from the front and rear and the left and right of the absorbent article.
[0002]
[Prior art]
Absorbents used in disposable diapers and disposable pants are usually pulp fibers (cotton-like pulverized pulp), heat-fusible fibers, highly water-absorbent resin powders, etc., mixed and conveyed from each storage tank. It is formed by sucking and depositing on the peripheral surface of the suction drum provided with a recess (suction region) having substantially the same shape as the absorber shape. The absorbent body sucked and deposited on the suction drum is transferred to a suction conveyor for conveyance, and is incorporated into a production line for disposable absorbent articles.
[0003]
Here, when the absorber has a two-layer structure, two suction drums are arranged in series and synchronously controlled, and on the lower layer absorber transferred from the upstream suction drum onto the suction conveyor, A method of placing an upper absorber formed with a suction drum is employed.
[0004]
In order to increase the amount of absorption of urine, etc., or to improve the adhesion to the lower crotch of a woman, the conventional two-layer structure absorber has an upper layer absorber having a smaller area than the lower layer absorber. Many of them had a convex cross section. However, such an absorbent body having a thick central portion is difficult to twist in accordance with the movement of the wearer, and there is a case where a gap is formed between the absorbent body and the excretory organ. Further, when the urine absorbing pad is used in combination, it becomes more and more bulky and gives the wearer an unpleasant feeling of stiffness.
[0005]
On the other hand, there is a problem in the method of dispersing the superabsorbent resin powder in the absorbent body during production of the absorbent body. As a method of dispersing the superabsorbent resin powder, there is a method of spraying the superabsorbent resin powder after molding the absorbent body with pulp fiber, heat-sealing fiber, etc. Is mixed with superabsorbent resin powder into pulp fibers that are air-carrying and deposited on a suction drum. However, since the amount of the superabsorbent resin powder used is considerably smaller than the amount of pulp fiber necessary for forming the absorbent body, it is difficult to uniformly mix with the pulp fiber in the conveying air. For this reason, as shown in the side view of the absorbent body manufacturing apparatus in FIG. 8, a thin tube 102 is inserted into a duct 101 that supplies pulp fiber 103 to the suction drum 100, and the high tube 102 A means for supplying the water absorbent resin powder 104 is employed.
[0006]
However, if the distance between the discharge hole of the thin tube 102 for supplying the superabsorbent resin powder and the suction drum 100 is long, that is, if it is L ₁ as shown in FIG. When the distance between the discharge hole of the thin tube 102 and the suction drum 100 is L ₂ shorter than L ₁ as shown in FIG. 9B, the width of the suction area 105 of the suction drum is increased. The scattering width becomes narrower than the width W of the suction region 105. As shown in FIG. 9B, the distance between the discharge hole of the thin tube 102 and the suction drum 100 is shortened because the superabsorbent resin powder falls by its own weight before reaching the suction drum 100, and is entirely in the suction drum 100. Therefore, the distance is naturally limited, and the design of the manufacturing apparatus for disposable absorbent articles is unavoidable. When the scattering width of the superabsorbent resin powder becomes narrower than the width W of the suction region 105, the superabsorbent resin powder is present in a high density near the central portion of the absorber, and the superabsorbent resin is very dense near the outer periphery. The absence of powder causes side leakage and leakage from the front-rear direction. In particular, the absorbent body having a convex cross-sectional structure has a problem in that it is highly likely that side leakage will occur because the superabsorbent resin powder is not so much scattered in the left and right regions.
[0007]
[Problems to be solved by the invention]
Therefore, in the present invention, it is easy to bend in accordance with the wearer's body shape and movement, and even if a separate urine collection pad is used in combination, it exerts a leak prevention effect without giving the wearer a feeling of stiffness, and the absorbent article. An object was to find an absorbent laminate having a simple structure capable of preventing leakage of effluent such as urine from the front and rear and from the left and right.
[0008]
[Means for Solving the Problems]
The present invention according to claim 1, which has solved the above problems, is an absorbent laminate for absorbing bodily fluids used in disposable absorbent articles, the absorbent laminate being a superabsorbent resin in pulp fibers. It is formed by superposing two upper and lower absorbent webs in which powder is dispersed, and the lower absorbent web is formed with the same or narrower width as the upper absorbent web. At least one opening having a smaller area than the lower absorbent web body is disposed in the overlapping portion with the web body, and the dispersion density of the superabsorbent resin powder is larger in the periphery of the opening than in other parts. It has a gist where it is set high.
[0009]
The absorbent laminate having the above structure has an opening in the upper absorbent web body and has a concave cross-sectional structure, so there is no bulkiness, and even if a separate urine collection pad is used together, it may be stiff lost. In addition, this absorbent laminate is easy to droop according to the wearer's body shape and movement due to the presence of the opening, and therefore there is no gap between the excretory organ and the absorbent body, and the leakage preventing effect is high. . Furthermore, the opening wall of the upper absorbent web body serves as a leak-proofing gland, and the superabsorbent resin powder is blocked by the leak-proofing gland because the high water-absorbing resin powder is dispersed and arranged around the opening in a high density. Was immediately absorbed by the highly water-absorbent resin, effectively preventing side leakage and longitudinal leakage.
[0010]
In the lower layer absorbent web material of the upper Symbol absorbent laminate, the superabsorbent polymer powder that substantially the entire region may be substantially dispersed in the same density. Since the lower absorbent web body is exposed in the opening, if the upper absorbent web body has a large opening, the absorbent properties can be improved if the superabsorbent resin powder is dispersed and disposed throughout the lower absorbent web body. Increased and further leakage prevention effect is expressed.
[0011]
Lower layer absorbent web material is being formed narrower than the upper absorbent web material, both longitudinal end edges of the upper absorbent web of absorbent laminate is extended outward than the longitudinal opposite edges of the lower absorbent web material It may be out. If the upper absorbent web is wide and the lower absorbent is narrow, it will be easy to roll according to the wearer's body shape and movement, and when it is rolled, the side of the upper absorbent web will be cross-shaped. Further, the leakage prevention effect of the opening wall is further exhibited.
[0012]
In the above SL absorbent laminate, the region including the central portion of the upper layer absorbent web material, the opening may be provided only one. This is because the opening is preferably disposed at the central portion where the excretory fluid concentrates. Further, with this configuration, even if the urine collecting pad is placed on the opening, it does not become bulky.
[0013]
The upper layer absorbent web material, two or more openings may be disposed substantially symmetrical positions. A large number of openings is preferable because it is easier to bend, and a high water-absorbing resin is present in a high density around the openings, so that the effect of preventing side and front / rear leakage is enhanced.
[0014]
The present invention also includes a disposable absorbent article comprising the above-mentioned absorbent laminate, and examples of the disposable absorbent article include disposable diapers, disposable pants, sanitary napkins, sanitary shorts, and the like.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a partially cutaway front view of a deployed state of a disposable diaper using a typical absorbent laminate of the present invention, and FIG. 2A is a schematic cross-sectional view corresponding to the line AA in FIG. FIG. 2B is a schematic cross-sectional view corresponding to the line BB in FIG. In these cross-sectional views, each component is shown separated for easy understanding. The disposable diaper 1 basically includes a back sheet 2, an absorbent laminate 3, a top sheet 4 narrower than the back sheet, and a pair of right and left rising bands 5.
[0016]
The backsheet 2 is composed of a synthetic fiber nonwoven fabric having a substantially hourglass-like water repellency, a synthetic resin film such as polyethylene (preferably a liquid-impermeable and breathable film) or a laminate thereof. Leg holes S are formed on both sides of the crotch between the abdomen P and the back Q. In consideration of touch feeling or when a mechanical surface fastener is used in the fastening system, it is preferable to use a laminate in which the outermost layer of the backsheet 2 is a nonwoven fabric or a woven or knitted fabric as the backsheet 2. The backsheet 2 may be a simple rectangular shape. As the non-woven fabric, those made of polypropylene, polyethylene, polyester, nylon or the like, or those made of a composite fiber such as polyester / polyester, polyester / polyethylene, polypropylene / polyethylene, etc. can be used.
[0017]
A plurality of waist elastic yarns 6 are attached to the upper surface of the front abdominal part P and the back part Q of the backsheet 2 in a stretched state in the width direction, and in the vicinity of the leg hole parts S on both sides, A plurality of leg elastic yarns 7 are attached to the upper surface of the backsheet 2 in a stretched state in the length direction. Instead of a plurality of elastic yarns, a belt-like elastic film or ribbon may be used.
[0018]
In addition, a frontal tape 8 is attached to the lower surface of the front abdomen P of the backsheet 2, and both sides of the lower surface of the back portion Q are pasted to the frontal tape 8 when used to fasten a disposable diaper in a three-dimensional manner. Each tape 9 is attached. As a fastening system, a mechanical surface fastener can be employed in addition to a method of attaching an adhesive to the fastening tape 9. A hook member may be attached to the fastening tape 9 to make the back sheet 2 a laminated type as described above, or at least the frontal tape 8 portion of the back sheet 2 may be a loop member such as a nonwoven fabric.
[0019]
The absorbent laminate 3 includes an upper layer absorbent web 31 having an opening 33 and a lower layer absorbent web 32. The upper-layer absorbent web body 31 has a substantially hourglass shape that is slightly smaller than the back sheet 2, and the lower-layer absorbent web body 32 is formed into a substantially rectangular flat body. These web bodies 31 and 32 are obtained by mixing pulp fibers and highly water-absorbent resin powder, and if necessary, heat-fusible fibers. The absorbent laminate 3 is bonded to the upper surface of the backsheet 1 with the lower absorbent web body 32 facing down. The absorbent laminate 3 will be described in detail later. The upper layer absorbent web 31 and the lower layer absorbent web 32 of the absorbent laminate 3 may be covered with a paper material (not shown) such as a tissue.
[0020]
The top sheet 4 is formed of a non-woven fabric or a woven fabric made of synthetic fiber having liquid permeability, and is formed in a rectangular shape having a narrower width and the same length as the back sheet 2, and the bottom surface of the top sheet 4 and the back sheet 2. Are substantially entirely bonded to each other with the absorbent laminate 3 and the waist elastic yarn 6 interposed therebetween. As the non-woven fabric or woven fabric, those made of the above-exemplified fibers or composite fibers can be preferably used, and the fibers or non-woven fabric / woven fabric may be subjected to a hydrophilization treatment in order to improve liquid permeability.
[0021]
The pair of left and right rising belt members 5 are made of a synthetic resin fiber nonwoven fabric having water repellency, have substantially the same length as the back sheet 2 and the top sheet 4, and the back sheet from the inside of the outer edge of the top sheet 4. A leg hole S having the same width as that of the back sheet 2 is formed. The overlapping part of each rising strip 5 with the top sheet 4 is joined to the top sheet 4, and the extended part extending outside the top sheet 4 is attached to the back sheet 2 with the leg elastic yarn 7 interposed therebetween. Be joined.
[0022]
Further, each rising band 5 has an inner edge 5a folded back inward, and the rising elastic yarn 10 is attached in an extended state in the folded portion over almost the entire length of the rising band 5. ing. The inner edge 5 a of the rising band 5 is joined to the top sheet 4 at the front and rear ends of the disposable absorbent article 1, and the inner edge 5 a is absorbed into the upper layer of the absorbent laminate 3 by contraction of the rising elastic yarn 10. The web body 31 is configured to stand up on the left and right upper surfaces.
[0023]
A waist gather, a leg gather, and a rise gather are naturally formed by the contraction force of the elastic yarns 6, 7, and 10. When worn, the waist gathers closely to the wearer's waist leg, and the rise gathers such as urine. Prevent side leakage.
[0024]
The absorbent laminate 3 of the present invention will be described in more detail. FIG. 3 is a front view of the absorbent laminate 3 having the same shape as that used in the disposable absorbent article shown in FIG. The absorbent laminate 3 is formed by laminating a substantially hourglass-shaped upper absorbent web 31 and a rectangular lower absorbent web 32 and bonding them at the overlapping portion. A rectangular opening 33 that is slightly smaller than the lower-layer absorbent web body 32 is formed at the center of the upper-layer absorbent web body 31 corresponding to the position where the lower-layer absorbent web body 32 is disposed. The lower absorbent web body 32 is configured to be exposed. 1 and 2, in the disposable diaper 1, the upper surface of the opening 33 is covered with a top sheet 4 (a paper material such as a tissue may be interposed between the top sheet 4). Therefore, in the actual absorbent article, the lower layer absorbent web body 32 is not exposed.
[0025]
The periphery of the opening 33 is set to have a high dispersion density of the superabsorbent resin powder as compared with other parts. That is, as shown in FIG. 4, the left and right side regions 31X (shaded portions) and the front and rear end regions 31Y (shaded portions) of the opening 33 have a higher water-absorbent resin powder dispersion density than the other portions 31Z. Is high. The superabsorbent resin powder is not only the upper surface of the upper absorbent web body 31 in the periphery of the opening 33, but also the upper absorbent web body as shown in FIG. Also in the thickness direction of 31, it is distributed at a high density and is also present near the surface of the opening wall 31 a forming the opening 33. Further, as shown in the cross-sectional view along the line D-D of FIG. 4 in FIG. Resin powder is dispersed at high density.
[0026]
Moreover, in the lower layer absorbent web body 32, it is preferable that the superabsorbent resin powder is dispersed at substantially the same density in almost the entire region. This is because even if the position, size, and the like of the opening 33 change depending on the type of the absorbent article, the lower-layer absorbent web body 32 exposed through the opening 33 always has a certain absorption capacity.
[0027]
In the absorbent laminate 3 shown so far, the lower layer absorbent web body 32 is formed narrower than the upper layer absorbent web body 31, and both longitudinal ends of the upper layer absorbent web body 31 are the longitudinal lengths of the lower layer absorbent web body 32. It has a structure that extends outward from both ends in the direction. Of course, both web bodies 31 and 32 may have the same width, and both end portions in the longitudinal direction of the upper layer absorbent web body 31 and both end portions in the longitudinal direction of the lower layer absorbent web body 32 may be aligned. When it extends outside the both ends of the lower layer absorbent web body, as shown in FIG. 5 (c), when the center part of the absorbent laminate 3 is deformed to rise in accordance with the movement of the wearer In addition, since the upper layer absorbent web 31 has a cross-sectional shape, the damming effect due to leakage prevention is further exhibited, and urine and the like are rapidly absorbed by the opening wall 33a and the lower layer absorbent web 32. This is a preferred embodiment. The upper layer absorbent web 31 is joined to the lower layer absorbent web 32 at the overlapping portion with the lower layer absorbent web 32. For example, when the vicinity of the periphery of the opening 33 is not bonded, the state shown in FIG. As shown in phantom lines, the left and right inner sides of the upper-layer absorbent web body 31 rise and small pockets 33a are formed, so that urine and the like can be absorbed more quickly.
[0028]
The shapes of the upper layer absorbent web 31 and the opening 33 are not limited to an hourglass shape or a rectangular shape, and may be any shape. FIGS. 6A to 6F show an example in which only one opening 33 is provided. In any example, the lower layer absorbent web body 32 larger than the opening 33 is disposed below the opening 33, but the lower layer absorbent web body 32 is omitted in FIG. 6 and FIG. 7 described later. . 6 (a) to 6 (e), an opening 33 including the center (intersection of the longitudinal center line and the width center line) of the upper layer absorbent web 31 is formed, and the position of excretory organs such as urine and the like Considering the case where the urine collecting pad is used together, it is preferable that the opening 33 exists in the central portion (the crotch portion) as described above. However, as shown in FIG. It is good also as the absorption laminated body 3 for men.
[0029]
7A to 7D show examples of the upper-layer absorbent web body 31 in which a plurality of openings 33 are provided. 7A and 7B show a configuration in which two openings 33 are arranged, (c) has three configurations, and (d) has four configurations. 7A to 7C, the opening 33 does not include the center of the upper-layer absorbent web body 31 (intersection of the longitudinal center line and the width center line), but the plurality of openings 33 are substantially symmetrical positions. Therefore, the structure is easier to bend. FIG. 7D shows a configuration in which the absorption performance is further improved because the opening 33 exists also in the central portion of the upper-layer absorbent web body 31.
[0030]
In the case of a conventional absorbent body having no opening 33, when it is drowned, it becomes a thick under-concave absorbent body and gives discomfort to the wearer, whereas it is shown in FIG. 3, FIG. 6 and FIG. The absorbent laminate 3 of the present invention is excellent in adhesion to the wearer because the absorbent laminate 3 is easy to roll because of the presence of the opening 33 and is effectively twisted according to the movement of the wearer. The structure is effective in preventing leakage of urine and the like. Moreover, when using a separate urine absorbing pad, the crotch part is prevented from becoming bulky by applying to the opening 33, and a comfortable wearing feeling can be obtained. In addition, the presence of the opening 33 can reduce the material cost of the absorbent laminate 3 and reduce the cost of the disposable absorbent article.
[0031]
In the upper layer absorbent web 31, the following method is efficient for dispersing the highly water-absorbent resin powder around the opening 33 with high density. That is, when forming the upper absorbent web body 31 by sucking and depositing the pulp fibers 103 and the superabsorbent resin powder 104 onto the suction area 105 of the suction drum 100 shown in FIG. 8, the opening 33 is formed in the upper absorbent web body 31. In order to form it, it is necessary to provide a non-suction area 106 corresponding to the opening 33 in the suction area 105 of the suction drum 100 (FIG. 10). Although the superabsorbent resin powder 104 collides with the non-suction area 106 by the air for conveyance, since the non-suction area 106 is not sucked, the superabsorbent resin powder 104 has four arrows in FIG. And scattered around the non-suction area 106, which is the nearest suction area 105. For this reason, the highly water-absorbent resin powder 104 is dispersed with high density around the opening 33 of the obtained upper-layer absorbent web 31.
[0032]
On the other hand, when the lower absorbent web body 32 is narrower than the upper absorbent web body 31, the distance between the superabsorbent resin powder supply thin tube 102 and the suction drum 100 is short as shown in FIG. However, even if there is only L ₂ , the superabsorbent resin powder can be dispersed at substantially the same density over the entire width of the lower layer absorbent web body 32, and the superabsorbent can be absorbed at the center of the absorbent body as in the prior art. The conductive resin powder is not biased. Even if the lower layer absorbent web body 32 has the same width as the upper layer absorbent web body 31, the vicinity of the outer peripheral portion of the lower layer absorbent web body 32 is covered by the upper layer web body 31, so that the high water absorption near the outer peripheral portion is high. Even if the density of the conductive resin powder is slightly lowered, the absorption performance is hardly affected.
[0033]
In addition to the disposable diaper shown in FIG. 1, the absorbent laminate 3 of the present invention is wrapped in a water-permeable material such as tissue as necessary, and includes disposable pants, a urine pad, a napkin, a sanitary short, It can be used as an absorbent body of a disposable absorbent article having a known structure such as incontinence shorts.
[0034]
【The invention's effect】
The present invention is configured as described above, and the upper layer absorbent web body and the lower layer absorbent web body having the openings are combined, so that the present invention can be effectively rolled according to the wearer's body shape and movement, and can be front and rear, left and right. It was possible to provide an absorbent laminate capable of preventing leakage of excretory fluid such as urine from the urine. Therefore, as an absorbent body for disposable pants, disposable diapers, urine-absorbing pads, sanitary napkins, sanitary shorts, light incontinence shorts, etc., it can be used at low cost without inconvenience such as leakage by incorporating it into disposable absorbent articles. Disposable absorbent articles can be easily provided. The absorbent laminate of the present invention can be used not only for disposable absorbent articles, but also for agricultural water retention / absorption materials, concrete curing mats, anti-condensation sheets, poultices, patches, cosmetics and the like.
[Brief description of the drawings]
FIG. 1 is a partially cutaway front view of a deployed state of a disposable diaper using a typical absorbent laminate of the present invention.
2A is a schematic cross-sectional view corresponding to the line AA in FIG. 1, and FIG. 2B is a schematic cross-sectional view corresponding to the line BB in FIG. 1;
FIG. 3 is a front view of a typical absorbent laminate of the present invention.
4 is an explanatory diagram of a dispersion state of a superabsorbent resin powder in the absorbent laminate of FIG. 3;
5A is a schematic cross-sectional view corresponding to the line CC in FIG. 4, FIG. 5B is a schematic cross-sectional view corresponding to the line DD in FIG. 4, and FIG. It is a cross-sectional schematic diagram equivalent to CC line of FIG.
FIGS. 6A to 6F are front views showing another embodiment of the upper layer absorbent web body and the opening.
FIGS. 7A to 7D are front views showing still another embodiment of an upper-layer absorbent web body and an opening.
FIG. 8 is a side view of the absorbent body manufacturing apparatus.
9 (a) and 9 (b) are plan views of the absorbent body manufacturing apparatus.
FIG. 10 is a plan view showing an embodiment of an apparatus for producing an upper layer absorbent web body of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Disposable diaper 2 Back sheet 3 Absorbing laminated body 4 Top sheet 5 Standing band material 6 Elastic thread for waist 7 Elastic thread for leg 8 Frontal tape 9 Fastening tape 31 Upper layer absorbent web body 32 Lower layer absorbent web body 33 Opening

Claims (7)

An absorbent laminate for absorbing bodily fluids used in disposable absorbent articles,
This absorbent laminate is formed by superposing two upper and lower absorbent webs in which superabsorbent resin powder is dispersed in pulp fibers,
The lower absorbent web body is formed to have the same or narrow width as the upper absorbent web body,
The upper absorbent web is provided with at least one opening having a smaller area than the lower absorbent web at the position where the lower absorbent web is provided. An absorbent laminate for disposable absorbent articles, characterized in that the dispersion density of the superabsorbent resin powder is set high.   In the lower layer absorbent web, the absorbent laminate according to claim 1, wherein the superabsorbent resin powder is dispersed at substantially the same density throughout the entire area.   The lower layer absorbent web is formed to be narrower than the upper layer absorbent web, and both longitudinal edges of the upper absorbent web are extended outward from both longitudinal edges of the lower absorbent web. Or the laminated body for absorption of 2.   The absorbent laminate according to any one of claims 1 to 3, wherein only one opening is disposed in a region including the central portion of the upper-layer absorbent web.   The absorbent laminate according to claim 1 or 2, wherein two or more openings are disposed in a substantially symmetrical position in the upper absorbent web body.   The periphery of the opening part of the upper layer absorbent web is set to have a high dispersion density of the superabsorbent resin powder over the entire thickness direction of the upper layer absorbent web as compared to other parts. The laminated body for absorption as described.   A disposable absorbent article comprising the absorbent laminate according to any one of claims 1 to 6.

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