JP2005034652A - Disposable diaper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disposable diaper which surely prevents the leakage from the sides by providing an absorbent layer which is excellent in diffusivity of excrement in the longitudinal direction, curves along the groin easily and shows excellent fitting performance. <P>SOLUTION: The disposable diaper 10 is equipped with the absorbent layer 31 made by forming flocculent pulp into a layer between a liquid permeable surface sheet 11 and a liquid impermeable reverse sheet 21 and a front body 3 and a back body 5 on the front and back sides in the longitudinal direction of the absorbent layer 31. Grooves 32a and 32b extending along the longitudinal direction are formed on the front surface 31a and the back side 31b of the absorbent layer 31. Preferably, the groove 32a on the front surface 31a and the groove 32b on the reverse side 31b are formed alternately in the width direction of the absorbent layer 31. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a disposable diaper.

  FIG. 12 shows a tape-type disposable diaper 100 conventionally provided on the market. Here, Fig. 12 (a) is a plan view of the disposable diaper 100 in a developed state, and Fig. 12 (b) is a longitudinal sectional view taken along line BB in Fig. 12 (a). The part to be bonded is indicated by a cross.

  As shown in FIG. 12 (b), this disposable diaper 100 includes a liquid-impermeable back sheet 21, a liquid-retaining absorbent layer 31, and a liquid-permeable material on the surface side of the external sheet 23 that forms the external shape of the diaper. The top sheets 11 are superposed in this order. And recently, in order to prevent side leakage of excretion fluid such as urine, a structure in which three-dimensional gathers 43 are provided along the left and right side edges of the absorption layer 31 has become mainstream.

  The flat outer shape of the disposable diaper 100 in the unfolded state has a substantially hourglass shape as shown in FIG. 12 (a), and the constricted portion located at the center in the longitudinal direction is applied to the crotch portion of the wearer. It is part 7. A front body 3 applied to the wearer's abdomen and a rear body 5 applied to the back extend from the crotch part 7 in the longitudinal direction. Then, both end portions in the width direction of the front body 3 and the back body 5 are joined together by a fastening tape or the like, so that a pair of left and right leg openings and a waist opening are formed.

  FIGS. 13A and 13B show a cross-sectional view around the trunk and a vertical cross-sectional view at the center of the wearer 1 in the wearing state, respectively. In addition, in order to avoid the complication of a figure, the back surface sheet 21 is not drawn. In the worn disposable diaper 100, the flexible absorbent layer 31 existing from the front body 3 to the back body 5 through the crotch 7 is flexibly deformed along the skin 1a of the wearer. By adhering to each other, the gap between the skin 1a is made as small as possible to prevent the side leakage 2a of excretory fluids such as urine, while the three-dimensional gather 43 stands on the absorption layer 31 to the skin 1a. In contact with each other, the side leakage 2a is prevented in a double manner. In the figure, the sideways leaking urine flow 2a is indicated by a dashed arrow. Moreover, since it becomes difficult to see the figure, the surface of the absorbent layer 31 that should be in contact with the skin is drawn away from the skin 1 a of the wearer 1.

  However, especially in adults, individual differences in the shape of these portions are increased due to the aging of the meat in the crotch portion and the crotch lining portion with age, and the degree of the difference in the shape depends on the flexibility. The bending deformability of the absorbent layer 31 is better. For this reason, depending on the person, a gap may be formed between the skin 1a and the side leakage 2a may occur.

  In addition, as shown in FIG. 12A, urination is normally concentrated toward the crotch part 7 of the diaper. For this reason, most of the urine is immediately absorbed by the central portion 31c in the longitudinal direction, which is a portion located in the crotch portion 7 of the absorption layer 31, or is quickly diffused from the central portion 31c to the front and rear portions in the longitudinal direction. If this portion is not absorbed or not, urine that is not immediately absorbed stays on the surface of the central portion 31c, and leaks to the outside of the diaper beyond the three-dimensional gather 43 during the stay. However, the absorption capacity is usually insufficient in the central portion 31c alone and cannot be absorbed completely, and the diffusibility in the longitudinal direction of the absorbent layer of the cotton-like pulp is poor, and it is absorbed immediately using the front and rear portions. I can't do that either. In particular, such retention can often occur in adults with large individual differences in urination volume and urination rate, and thus the prevention of side leakage is an important issue as aging progresses. It has become.

  The present invention has been made in view of such conventional problems, and is excellent in diffusibility of excretory fluid in the longitudinal direction, and is easily bent along the crotch portion to ensure a side leak by providing an absorbent layer having a good fit. An object is to provide a disposable disposable diaper.

  In order to achieve this object, the invention shown in claim 1 comprises an absorbent layer formed by laminating a cotton-like pulp between a liquid-permeable top sheet and a liquid-impervious back sheet, In the disposable diaper in which a front body and a back body are provided on the front and back sides in the longitudinal direction of the absorbent layer, grooves along the longitudinal direction are formed on the front and back surfaces of the absorbent layer.

  According to the said invention, excretion liquids, such as urine excreted mainly in the center part of the longitudinal direction of an absorption layer, can be immediately induced | guided | derived now before and after a longitudinal direction by the said groove | channel. And since the excretory fluid induced | guided | derived before and after is spread | diffused and absorbed in the width direction from there, it becomes possible to absorb excretion fluid instantly not only in the center part but also in the front and back parts in the longitudinal direction. That is, the excretory fluid can be quickly diffused over a wide area from the central portion, and can be immediately absorbed in the wide area. Therefore, the staying amount in the central portion can be reduced, and side leakage can be prevented more reliably.

  The groove is formed not only on the front surface of the absorption layer but also on the back surface. Therefore, the excretory fluid that has penetrated in the thickness direction at the central portion in the longitudinal direction and has not been absorbed and reaches the back surface is immediately guided through the groove formed on the back surface, and is immediately guided back and forth in the longitudinal direction. Absorbed in the part. Therefore, the diffusibility of the excretory fluid in the longitudinal direction is further improved, the amount of staying in the central portion can be reduced, and side leakage can be prevented more reliably.

  Furthermore, the absorption layer can be bent not only along the front surface but also along a groove formed on the back surface. Therefore, compared to the case where the groove is formed only on the surface, the direction of bending deformation of the absorbent layer is small, that is, it can be deformed into a concave shape or a convex shape, and this is applied. It can be freely and flexibly deformed in a concave or convex shape along the line of the wearer's crotch. Therefore, even for an adult crotch shape with great individual differences, it can be bent and fit along the line of each crotch, making it difficult to form a gap with the wearer's skin, thus ensuring side leakage Can be prevented.

According to a second aspect of the present invention, in the disposable diaper according to the first aspect, the groove on the front surface and the groove on the back surface are alternately formed in the width direction of the absorbent layer.
According to the above invention, the front surface groove and the back surface groove are alternately formed in the width direction, that is, the front and back surface grooves are not formed at the same position in the width direction. Therefore, it is possible to prevent the thickness of the absorbent layer where the groove is formed from becoming extremely excessively thin, thereby suppressing an extreme decrease in the strength of the absorbent layer and preventing its fragmentation, and providing a good bending deformability. be able to.

According to a third aspect of the present invention, in the disposable diaper according to the first or second aspect, at least one groove is formed in a central portion in the width direction on one surface of the front and back surfaces. In the other surface, at least one groove is formed at both ends in the width direction.
According to the said invention, it can be bent in this center part by the groove | channel formed in at least 1 center part of the width direction. In addition, these end portions can be bent by grooves formed at least one at each of the both end portions. Therefore, the absorbent layer can be flexibly bent in the width direction by these three grooves formed at each position in the width direction, and can be fitted along the line of the crotch portion of the wearer.

According to a fourth aspect of the present invention, in the disposable diaper according to the third aspect, the one surface is a back surface and the other surface is a surface.
According to the invention described above, the groove is formed on the surface of the absorption layer one by one at both ends in the width direction. For this reason, this groove | channel functions also as a side groove | channel which stops the excretion liquid which retains on the absorption layer surface from flowing out from an absorption layer to the width direction. Therefore, outflow of excretion fluid from both ends of the absorption layer can be prevented, and side leakage can be further reliably prevented.

  Further, most of the excretory fluid is excreted on the surface of the central portion in the width direction, particularly in the central portion in the longitudinal direction. For this reason, in particular, a large amount of excretory fluid that has penetrated in the thickness direction without being absorbed reaches the back surface of the central portion in the width direction. However, since a groove is formed in the center in the width direction on the back surface, the excretory fluid that has reached the back surface can be quickly guided back and forth by the groove. Therefore, the diffusibility of the excretory fluid in the longitudinal direction is further improved, and the staying amount in the central portion can be further reduced.

The invention shown in claim 5 is the disposable diaper according to any one of claims 1 to 4, wherein the groove width is 5 to 30 mm.
According to the above invention, since the groove width is 5 mm or more, the bending deformability of the absorbent layer can be increased, and the excretory fluid diffusibility by the groove is also excellent. Further, since the groove width is 30 mm or less, the total amount of the cotton-like pulp in the absorbent layer is not extremely reduced, and a predetermined possible absorption capacity can be maintained.

According to a sixth aspect of the present invention, in the disposable diaper according to any one of the first to fifth aspects, the interval between the grooves adjacent to each other in the width direction is widened from the central portion toward the end portion in the longitudinal direction. It is characterized by that.
According to the said invention, the excretion liquid with which most excretion is carried out in the center part of the width direction in the center part of the said longitudinal direction is guide | induced to the front and back of a longitudinal direction by the said groove | channel. At this time, since the interval between the grooves becomes wider from the central part in the longitudinal direction to the end part, the excretion fluid excreted in the central part in the width direction is guided to the end part in the longitudinal direction. However, it can be guided in the width direction at the same time, and can be diffused over a wide range in a short time. Therefore, the amount of staying in the central portion can be further reduced, so that side leakage can be more reliably prevented.

  ADVANTAGE OF THE INVENTION According to this invention, providing the disposable diaper which is excellent in the diffusibility to the longitudinal direction of excretion liquid, can prevent a side leak reliably by providing the absorption layer which is easy to bend along a crotch part, and is rich in fitting property. it can.

  Hereinafter, embodiments of the present invention will be described in detail by taking a tape-type disposable diaper, that is, a disposable diaper of a type in which a front body and a back body are joined with a fastening tape when worn. The present invention can be applied to a pants-type disposable diaper in which the front body and the back body are joined in advance.

Fig.1 (a) is a top view in the expansion | deployment state of the disposable diaper of 1st Embodiment based on this invention, FIG.1 (b) is a longitudinal cross-sectional view of the BB line arrow in Fig.1 (a). is there.
As shown in FIG. 1, the disposable diaper 10 includes a liquid-permeable top sheet 11, a liquid-impervious back sheet 21 having an absorbent body 30 interposed between the top sheet 11 and the back sheet. An outer sheet 23 that forms a side flap 51 together with a three-dimensional gather sheet 41, which will be described later, at a portion (both sides of the diaper 10) that extends to the side of the absorber 30 while covering the entire back side of the absorber 21, and an absorber on the top sheet 11 The three-dimensional gathers sheet 41 is mainly composed of a three-dimensional gather sheet 43 that is formed over the longitudinal direction.

  The absorbent body 30 is mainly composed of an absorbent layer 31 having a substantially planar hourglass shape in which a cotton-like pulp such as a cellulose fiber material is formed in layers, and the entire absorbent layer 31 is wrapped with crepe paper as a water-permeable sheet 33. Consists of. Specifically, the front and back surfaces and the four side surfaces of the absorbent layer 31 are wrapped and covered with the crepe paper 33 in a spring roll shape. In addition, as for the thickness of the said absorption layer 31, 5.0-40.0 mm is desirable, and in order to enlarge the possible absorption capacity | capacitance of the absorption layer 31, it is preferable to add a polymeric absorbent polymer to the said cotton-like pulp. desirable. The reason why the above range is preferable as the thickness of the absorbent layer 31 is that when the thickness is less than 5.0 mm, the absorption capacity is lowered. Because it becomes.

  The back sheet 21 is disposed on the back surface side of the absorber 30, and is attached to cover the entire back surface of the absorber 30, and the edge of the back sheet 21 that wraps around from the back surface to the front surface side, The back sheet 21 and the absorbent body 30 are bonded and integrated to each side surface of the absorbent body 30. This sticking is performed by a hot melt adhesive. In addition, the description regarding the adhesion | attachment which comes out in the following description is made | formed by a hot-melt-adhesive fundamentally, and it does not explain each time.

This back sheet 21 is for improving the leak-proof property on the back side of the diaper, and a polyethylene plastic film or the like is suitable as the material. Preferably, the polyethylene film is provided with a large number of micropores that do not allow liquid molecules to permeate to prevent moisture.
Further, if necessary, the surface of the absorbent body 30 may be covered with a non-woven fabric diffusion sheet (not shown) so as to cover the entire surface so as to promote the surface diffusion of urine.

  The surface of the absorber 30 is covered with the liquid-permeable surface sheet 11 over the entire surface. Then, the portion 11 a of the topsheet 11 that slightly extends sideways from the absorber 30 is bonded to a postscript outer shape sheet 23 disposed on the back surface side of the absorber 30, so that the absorber 30 is interposed between both sheets 11 and 23. Is held. The surface sheet 11 is a hydrophilic nonwoven fabric, woven fabric, or the like, and its constituent fibers are composed of single fibers such as polypropylene, polyethylene, polyester, nylon, or composite fibers composed of two or more of these. .

  The outer sheet 23 has an hourglass shape similar to that of the absorber 30 in plan view, but is larger in plan than the absorber 30 and extends largely laterally from the absorber 30. The portion constitutes a side flap 51 with a three-dimensional gather sheet 41 described later. And the said absorber 30 is distribute | arranged in the center of the longitudinal direction of this external sheet 23, making a mutual constriction part correspond, and it sticks with the extension part 11a of the surface sheet 11 which covers the absorber 30 surface mentioned above. The As the outer shape sheet 23, a single layer nonwoven fabric sheet having both air permeability and water repellency, or a multilayer nonwoven fabric sheet in which a nonwoven fabric having water repellency is bonded to a nonwoven fabric having air permeability can be used. In this outer shape sheet 23, elastic elastic members such as thread rubber and belt rubber are appropriately arranged in the width direction and the longitudinal direction as needed, or the outer shape sheet 23 itself is made of an elastic elastic material. Accordingly, the elastic sheet 23 may be given elastic elasticity.

  The three-dimensional gather sheet 41 is made of a water-repellent sheet base material, and covers the side edge portion of the absorbent body 30 with the top sheet 11 interposed therebetween, and is disposed along the longitudinal direction of the absorbent body 30. And it sticks to the surface sheet 11 or the external sheet 23 along the side edge of the absorber 30, and forms the base end 45 of the solid gathers 43. FIG. The front end portion 47 of the three-dimensional gather 43 stands on the side edge portion of the absorbent body 30 via the top sheet 11, while the proximal end portion 49 can come into contact with and separate from the top sheet 11 surface on the absorbent body 30. overlapping. The base end 45 extends laterally in the same shape as the outer sheet 23, and the extended portion 42 is bonded to the outer sheet 23 to form a side flap 51. The side flap 51 is formed wide for the front body 3 applied to the wearer's abdomen and the back body 5 applied to the back, while the crotch lower part 7 applied to the crotch is formed narrow so that it is a disposable diaper. 10 has an hourglass shape in plan view.

  The three-dimensional gather sheet 41 is used in a state where two sheets are folded at the tip 47a of the three-dimensional gather 43, and at least one thread-like rubber along the longitudinal direction is provided at the folded-up portion 47a of the tip. 53a is interposed. The thread rubber 53a is bonded and fixed to the folded portion 47a in an expanded state, and the folded portion 47a is contracted in the longitudinal direction. And the front end side part 47 of the said three-dimensional gather 43 stands by this contraction force.

  Such a three-dimensional gather sheet 41 uses a water-repellent nonwoven fabric or woven fabric as a sheet base material, and these constituent fibers are single fibers such as polypropylene, polyethylene, polyester, nylon, or polypropylene, polyethylene, polyester, nylon, etc. The composite fiber which consists of two components of these can be used.

  Further, along the side edge of the side flap 51, a plurality of thread-like rubbers 53b are interposed and fixed between the two stacked sheets 41 in an extended state, and the leg gathers are formed by the contraction force. . As the thread rubbers 53a and 53b, materials such as styrene rubber, olefin rubber, urethane rubber, ester rubber, polyurethane, polyethylene, polystyrene, styrene butadiene, silicon, and polyester are applied. Note that the thread-like rubber 53b is not an essential component, and there is no need to gather around the legs.

  Fastening tapes 55 for joining the side flaps 51 to the side flaps 51 of the front body 3 and causing the wearer to wear the diapers 10 are provided on both side ends 51a of the side flaps 51 of the rear body 5, respectively. It has been.

  A state in which the disposable diaper 10 having the above configuration is attached to the wearer is shown in the longitudinal sectional view of the center of the wearer in FIG. As described above, the flexible absorbent layer 31 existing from the front body 3 to the back body 5 through the crotch 7 is flexibly deformed and adhered along the skin 1a of the wearer 1. Thus, while preventing the side leakage 2a, the tip side portion 47 of the three-dimensional gather 43 standing along the side edges of the absorber 30 abuts against the skin 1a of the wearer 1 to form a weir, and double The leak 2a is prevented. However, unlike the conventional example shown in FIG. 13, in the present invention, the bending deformability of the absorbent layer 31 is remarkably improved by the grooves 32 a and 32 b formed in the absorbent layer 31. In FIG. 2, the surface of the absorbent layer 31 that should be in contact with the wearer 1 is drawn away from the skin 1 a of the wearer 1 because the drawing is difficult to see.

  The configuration described above is substantially the same as that of a normal disposable diaper, and the contents described below are characteristic features of the present invention.

Fig.3 (a) is a top view which shows a partially broken disposable diaper in the expansion | deployment state of this 1st Embodiment, FIG.3 (b) is a BB line arrow view in Fig.3 (a). It is a longitudinal cross-sectional view.
As shown in FIG. 3, several straight grooves 32 a and 32 b along the longitudinal direction are formed on the front surface 31 a and the back surface 31 b of the absorption layer 31 of the absorber 30 described above, and the interval in the width direction is set in the longitudinal direction. It is formed so as to be kept constant. Specifically, with respect to the back surface 31b, one linear groove 32b having a rectangular cross section is formed at the center in the width direction, and one straight groove 32a having the same rectangular cross section is formed at each end in the width direction on the front surface 31a. Has been.

  The 32a and 32b grooves are used for immediately guiding and diffusing excretion liquid, most of which is excreted in the central portion 31c in the longitudinal direction of the absorbent layer 31, before and after the longitudinal direction of the absorbent layer 31 when the wearer excretes. (Refer to the alternate long and short dash line arrow in the figure), which makes it possible to quickly absorb the excretory fluid over a wide range of the absorption layer 31. And the retention amount of the excretion liquid on the surface sheet 11 can be reduced, and thus the lateral leakage of the excretion liquid leaking out of the diaper 10 over the three-dimensional gather 43 can be prevented.

  The grooves 32a and 32b are formed not only on the front surface 31a but also on the back surface 31b. Therefore, the excretory fluid that has penetrated the absorbing layer 31 in the longitudinal direction at the central portion 31c in the longitudinal direction and has not been absorbed and reaches the back surface 31b is immediately transmitted through the groove 32b formed in the back surface 31b. It is guided back and forth and is immediately absorbed at the front and back. Therefore, the diffusibility of the excretory liquid in the longitudinal direction is further improved, the amount of stay in the central portion 31c can be reduced, and thus side leakage can be prevented more reliably.

  In addition, as shown in FIG. 2, the absorbing layer 31 can be bent not only along the groove 31b formed on the back surface 31b but also on the back surface 31b. Therefore, the directionality of the bending deformation of the absorption layer 31 is smaller than when the groove is formed only on the surface 31a. That is, when the groove is formed only on the front surface 31a, the front surface 31a is easily bent so as to be concave and is difficult to be bent. However, in the present invention, not only on the front surface 31a but also on the back surface 31b. Since the groove 32b is formed, the direction of bending deformation of the absorption layer 31 is small, and it can be bent flexibly in a concave shape or a convex shape. Therefore, the absorbent layer 31 is freely and flexibly deformed in a concave or convex shape along the line of the wearer's crotch portion to which the absorbent layer 31 is applied. It bends and fits along the crotch line, so that side leakage can be more reliably prevented.

  As shown in FIG. 3, the grooves 32a and 32b are alternately formed in the width direction on the front surface 31a and the back surface 31b. In the present embodiment, as described above, the width of the back surface 31b is determined in the width direction. One is formed only at the center of the surface, while one is formed at each end in the width direction on the surface 31a.

  The reason why these are alternately formed is that when the grooves of the front and back surfaces 31a and 31b are formed at the same position in the width direction, the thickness of the absorption layer 31 in the portion where the grooves are formed becomes extremely thin, and absorption is performed. This is because the layer 31 is insufficient in strength and may be divided.

  Moreover, the reason why the grooves 32a and 32a are formed one by one at each end in the width direction of the surface 31a is that if the grooves 32a and 32a are formed in this position, the grooves 32a and 32a are excreted on the surface 31a after excretion. This is because the liquid also functions as a side groove that prevents the liquid from flowing out from the absorption layer 31 in the width direction. On the other hand, the reason why the groove 32b is formed in the central portion of the back surface 31b is that a large amount of excretory liquid penetrates into the central portion in the width direction and reaches the back surface, particularly in the central portion 31c in the longitudinal direction. . That is, as described above, most of the excretion is performed in the central portion 31c in the longitudinal direction, but among these, it is concentrated in the central portion in the width direction. For this reason, in particular, a large amount of excretory fluid reaches the back surface 31b of the central portion in the width direction through the absorption layer 31 in the thickness direction. However, if the groove 32b of the back surface 31b is formed in the center portion in the width direction as in the present embodiment, the excretory fluid that has penetrated in the thickness direction in the center portion in the width direction and has reached the back surface 31b is the groove. 32b is immediately guided in the longitudinal direction in the longitudinal direction, and as a result, it can be absorbed immediately in the front and back portions.

  Such grooves 32a and 32b are formed with a constant width over the longitudinal direction. Here, the groove width is desirably set to a predetermined value of 5 to 30 mm. If the groove width is 5 mm or more, the bending deformability of the absorption layer 31 can be increased and the fitting property is excellent, and the maximum flow rate that the grooves 32a and 32b can flow per unit time increases and diffusion of excretory fluid. Excellent in properties. Moreover, if the groove width is 30 mm or less, the amount of cotton-like pulp in the absorbent layer 31 will not be extremely reduced, and a predetermined possible absorption capacity can be maintained.

  In addition, the depth of the grooves 32a and 32b is preferably set to 30 to 50% of the thickness of the absorption layer 31. The reason for this is that if the thickness is 50% or more, the portion where the groove is formed may be insufficient in strength, whereas if it is 30% or less, the maximum flow rate of excretory fluid that can flow per unit time decreases, This is because the diffusibility of the excretory fluid in the longitudinal direction is reduced.

  In the first embodiment, a total of three grooves 32a and 32b are formed, one at the center in the width direction of the back surface 31b and one at each end in the width direction of the front surface 31a. However, as long as the front and back surfaces 31a and 31b are alternately formed in the width direction, the number and the formation position in the width direction are not limited to the above.

  For example, FIG. 4 shows a vertical cross-sectional view of the first modification taken along line BB, but as shown in the drawing, the groove arrangement in the width direction may be reversed from the first embodiment. That is, the grooves 32a and 32b may be formed one at the center in the width direction of the front surface 31a and one at each end in the width direction of the back surface 31b. And according to this structure, the excretion liquid excreted by the center part of the width direction in the center part 31c of a longitudinal direction is immediately back and forth in the longitudinal direction by the groove | channel 32a located in the center part of the width direction of the surface 31a. And can be guided.

  Moreover, although the longitudinal cross-sectional view of the BB line arrow of a 2nd modification is shown in FIG. 5, you may increase the number of grooves like illustration. That is, as shown in the figure, the front surface 31a is formed with grooves 32a at the center and each end in the width direction, and the back surface 31b is formed with three grooves 32a, 32a, 32a of the surface 31a in the width direction. It may be formed in the middle of 32a. According to this configuration, since the number of grooves is large, the bending deformability of the absorbent body 30 is further improved and the direction of bending deformation is further reduced. Also, it can be bent to fit along the crotch line to prevent side leakage more reliably.

  The disposable diaper according to the first embodiment and the modification thereof described above includes the crepe paper 33 that is a liquid-permeable sheet that encloses and retains the absorbent layer 31, but is not limited thereto. Instead, the crepe paper 33 may be omitted as shown in a longitudinal sectional view taken along line B-B in FIG.

FIG. 7: is a longitudinal cross-sectional view of the BB line arrow which shows 2nd Embodiment based on this invention.
The first embodiment is different from the second embodiment in that the absorption layer 31 is composed of two layers when the absorption layer 31 of the absorber 30 is composed of a single layer. That is, the absorption layer 31 according to the second embodiment is configured by stacking separate independent absorption layers 34 and 35 on the top and bottom as illustrated. And in the state which these were piled up, it was wrapped and integrated with the said crepe paper 33, and it has become one absorber 30.

  The upper surface side absorption layer 34 in this figure has grooves 34a formed at each end in the width direction, while the lower surface side absorption layer 35 in the figure has an absorption layer 35 at its center. A groove 35b is formed. And these groove | channels 34a and 35b become the penetration groove | channel 34a (35b) which penetrates only the absorption layer 34 (35) in which each groove | channel 34a (35b) was formed over the thickness direction. And according to the structure of this through-groove, while the back-side absorption layer 35 is adjacent to the through-groove 34a formed in the front-side absorption layer 34, conversely to the back-side absorption layer 35, A surface-side absorption layer 34 is adjacent to the formed through groove 35b. Therefore, the excretion liquid accumulated in the through groove 34a of the absorption layer 34 on the front surface side is absorbed into the absorption layer 35 on the back surface side, and the excretion liquid accumulated in the penetration groove 35b of the absorption layer 35 on the back surface side is absorbed on the surface side. It becomes easy to permeate into the layer 34, so that the diffusion rate of the excretory fluid absorbed in each of the absorption layers 34 and 35 can be improved.

  Here, the reason why the absorption layer has a two-layer structure and the grooves 34a and 35b are formed as through grooves will be described. Usually, the absorption layer 31 is manufactured by molding cotton-like pulp into an hourglass shape by the fiber-splitting machine 200 shown in FIG. The fiber stacking machine 200 includes a belt conveyor 210 and a rotating drum 220 that rotates in synchronization with the belt conveyor 210 above the belt conveyor 210. The outer peripheral surface of the rotating drum 220 has a plurality of hourglass-shaped concave portions 222, and the cotton pulp put into the concave portions 222 by the cotton-like pulp feeding device 224 arranged facing the outer peripheral surface is used as the belt. The absorbent layer 31 is formed on the belt conveyor 210 by transferring the outer peripheral surface to the conveyor 210 while abutting it. Then, the molded absorbent layer 31 is conveyed to the next process by the belt conveyor 210.

  Here, if it is the groove | channel 32a by the surface 31a side of the absorption layer 31, the groove | channel 32a can be formed by providing the groove | channel formation convex part 223 in the said recessed part 222, as shown in FIG. However, since there is no molding frame like the concave portion 222 on the back surface 31b side, the groove 32b on the back surface side 31b cannot be formed. Moreover, since the belt conveyor 210 becomes obstructive with respect to the absorption layer 31 conveyed by the belt conveyor 210 after shaping | molding, the back surface of a groove | channel engraving rod not shown from the bottom is raised / lowered suitably at timing etc. The groove 32b cannot be formed on the 31b side. Further, since the absorbent layer 31 of the cotton-like pulp is fragile and easily collapses, the groove cannot be formed from above by the groove engraving rod after the upper and lower sides are turned over and the back surface 31b side is directed upward.

  On the other hand, if the absorption layer has a two-layer structure and the groove is a through groove as in the second embodiment, an absorption layer having grooves on both sides can be easily manufactured as follows. Become. That is, as shown in FIG. 9, a fiber spreader 200 b for forming the back-side absorbent layer 35 is separately installed below the fiber spreader 200 a for forming the front-side absorbent layer 34. Meanwhile, in the concave portion 222a of the rotary drum 220a of the front side fiber stacker 200a, two convex portions 223a for forming the through grooves 34a are formed at the respective end portions in the width direction of the absorbent layer 34, A convex portion 223b for forming a through groove 35b is formed in the central portion in the width direction of the absorbent layer 35 in the concave portion 222b of the rotary drum 220b of the back side fiber stacker 200b. Then, the absorbent layers 34 and 35 are separately formed by the fiber stackers 200a and 200b, and then the upper side of the absorbent layer 35 on the back surface side while adjusting the timing of the two belt conveyors 210a and 210b of the fiber spreaders 200a and 200b. If the two are superposed by dropping the absorption layer 34 on the surface side, an absorption layer having grooves on both sides is obtained.

  In addition, about 2nd Embodiment mentioned above, although the absorption layer 34 of the surface side and the absorption layer 35 of the back surface side were directly contacted, it overlapped up and down, but the longitudinal cross-section of the BB arrow of FIG. As shown in the figure, a water-permeable sheet 36 may be interposed between the two to prevent mutual contact. According to this configuration, the excretory fluid that has flowed into the through groove 34a of the absorption layer 34 on the front surface side is diffused in a plane through the liquid-permeable sheet 36, and covers the entire surface of the absorption layer 35 on the back side. The diffusion rate is improved. As the water permeable sheet 36, crepe paper or the like can be used.

  FIG. 11: is a top view which shows partially the disposable diaper 10 in the expansion | deployment state of 3rd Embodiment based on this invention. In the first embodiment, the grooves 32a and 32b are formed as straight grooves, and the interval between adjacent grooves in the width direction is constant over the longitudinal direction. In the third embodiment, the width direction Are different in that the distance between the adjacent grooves 32a and 32b is increased from the longitudinal central portion 31c toward the end portion. That is, in the third embodiment, the linear groove 32b is formed at the center in the width direction of the back surface 31b, while the two grooves 32a formed at each end in the width direction of the front surface 31a. Is formed in a line-symmetrical arc with respect to the linear groove 32b of the back surface 31b in the plan view, and is closest to the central portion 31c in the longitudinal direction.

  And according to this structure, the excretion liquid in which the majority is excreted in the central portion in the width direction of the central portion 31c in the longitudinal direction is guided to the grooves 32a and 32b and moves back and forth in the longitudinal direction. Go. At this time, since the interval between the grooves 32a and 32b becomes wider from the central portion 31c in the longitudinal direction toward the end portion, the excretion fluid excreted in the central portion in the width direction is transferred to the end portion in the longitudinal direction. At the same time, it can be guided in the width direction and diffused in a wide range in a short time.

As mentioned above, although embodiment which concerns on this invention was described, this invention is not limited to this embodiment, The deformation | transformation as shown below is possible in the range which does not deviate from the summary.
In the present embodiment, the shape of the absorber 30 is formed in a substantially hourglass shape in plan view, but is not limited to this, and may be rectangular in plan view.
In the first embodiment, the cross-sectional shapes of the grooves 32a and 32b are rectangular. However, the present invention is not limited to this, and may be a semicircular shape, a semielliptical shape, or the like.

Fig.1 (a) is a top view in the expansion | deployment state of the disposable diaper of 1st Embodiment based on this invention, FIG.1 (b) is a longitudinal cross-sectional view of the BB line arrow in Fig.1 (a). is there. Fig.2 (a) is a longitudinal cross-sectional view of a wearer center in the wearing condition of the disposable diaper of 1st Embodiment. Fig.3 (a) is a top view which shows partially the disposable diaper in the expansion | deployment state of 1st Embodiment, and FIG.3 (b) is a vertical section of the BB line arrow in Fig.3 (a). FIG. It is a longitudinal cross-sectional view which shows the 1st modification of 1st Embodiment by the BB line arrow in Fig.3 (a). It is a longitudinal cross-sectional view which shows the 2nd modification of 1st Embodiment by the BB line arrow in Fig.3 (a). It is a longitudinal cross-sectional view which shows the modification of 1st Embodiment by the BB line arrow in Fig.3 (a). It is a longitudinal cross-sectional view which shows the disposable diaper of 2nd Embodiment which concerns on this invention by the BB line arrow in FIG. 3 (a). It is a perspective view of the fiber stacker for demonstrating that it is difficult to form a groove | channel on the back surface of an absorption layer. It is a perspective view of the fiber stacker for demonstrating that a groove | channel can be easily formed in both surfaces if it is an absorption layer of the 2 layer structure concerning 2nd Embodiment. It is a longitudinal cross-sectional view which shows the modification of 2nd Embodiment by the BB arrow line in Fig.3 (a). It is a top view which fractures | ruptures and shows the disposable diaper in the expansion | deployment state of 3rd Embodiment which concerns on this invention. Fig.12 (a) is a top view in the expansion | deployment state of the conventional disposable diaper, FIG.12 (b) is a longitudinal cross-sectional view of the BB line arrow in Fig.12 (a). Fig.13 (a) is a cross-sectional view around the trunk | drum of the disposable diaper of a wearing condition, FIG.13 (b) is a longitudinal cross-sectional view of a wearer center.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wearer 10 Disposable diaper 11 Top sheet 21 Back sheet 23 Outline sheet 30 Absorber 31 Absorbing layer 31a Surface 31b Back surface 32a, 32b Groove 41 Three-dimensional gather sheet 42 Extension part of three-dimensional gather sheet 43 Three-dimensional gather 45 Base end 47 Front side Part 49 Base end part 51 Side flap

Claims (6)

Between the liquid-permeable top sheet and the liquid-impervious back sheet, an absorbent layer formed by forming a cotton-like pulp into a layer is provided, and a front body and a back body are provided on the front and back sides in the longitudinal direction of the absorbent layer. In the disposable diaper provided,
The disposable diaper characterized by the groove | channel along the said longitudinal direction being formed in the surface and the back surface of the said absorption layer.   The disposable diaper according to claim 1, wherein the groove on the front surface and the groove on the back surface are alternately formed in the width direction of the absorption layer.   At least one groove is formed in the center in the width direction on one surface of the front and back surfaces, and at least one groove is formed on both ends in the width direction on the other surface. The disposable diaper according to claim 1, wherein the disposable diaper is provided.   The disposable diaper according to claim 3, wherein the one surface is a back surface and the other surface is a surface.   The disposable diaper according to any one of claims 1 to 4, wherein the groove width is 5 to 30 mm. The disposable diaper according to any one of claims 1 to 5, wherein an interval between grooves adjacent to each other in the width direction is widened from a center portion in the longitudinal direction toward an end portion.

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