Apparatus for manufacturing absorbent body and apparatus for manufacturing absorbent article

Abstract

An object of the present invention is to provide an apparatus for manufacturing an absorbent body and an apparatus for manufacturing an absorbent article that can adjust the distribution of SAP particles contained in the absorbent body.SOLUTION: An apparatus for producing an absorbent body is provided with an SAP supply section for supplying SAP particles, the SAP supply section comprising an inclined section which is inclined obliquely downward, a plurality of branch paths which are provided in the inclined section and branch from each other in a flow path through which SAP particles of a highly absorbent polymer pass, and an adjusting section for adjusting the distribution of the SAP particles passing through the branch paths, a mesh-like frame provided on the outer peripheral surface of the SAP supply section which is arranged to face the lower end of the SAP supply section, and an absorbent material containing the SAP particles supplied by the SAP supply section is deposited in the frame. And a hollow cylindrical rotating body that forms an absorption mat constituting the absorber and conveys the formed absorption mat in an outer peripheral direction.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an apparatus for manufacturing an absorbent body and an apparatus for manufacturing an absorbent article. [Background technology]

[0002] Absorbent articles such as disposable diapers, absorbent pads, sanitary napkins, etc. For example, Patent Document 1 discloses a tape-type disposable diaper having an absorbent body made of an absorbent material containing SAP, a highly absorbent polymer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-068464 Summary of the Invention [Problem to be solved by the invention]

[0004] The SAP particles are dispersed in the absorbent body during the manufacturing process, but it is difficult to adjust the distribution of sand-like SAP particles during dispersion.

[0005] An object of the present invention is to provide an absorbent body manufacturing apparatus and an absorbent article manufacturing apparatus that are capable of adjusting the distribution of SAP particles contained in the absorbent body. [Means for solving the problem]

[0006] An apparatus for manufacturing an absorbent body according to one aspect of the present invention comprises: a SAP supply unit having an inclined portion inclined obliquely downward, a plurality of branch paths formed on the inclined portion, through which SAP particles pass, and an adjusting unit for adjusting the distribution of the SAP particles passing through the plurality of branch paths, and for supplying the SAP particles; The device has a mesh-like formwork on its outer peripheral surface positioned opposite the lower end of the SAP supply unit, and is configured to deposit absorbent material containing SAP particles supplied by the SAP supply unit onto the formwork to form an absorbent mat that constitutes the absorbent body, and a hollow cylindrical rotating body that transports the formed absorbent mat in the outer circumferential direction. [Effects of the Invention]

[0007] According to the present invention, it is possible to adjust the distribution of SAP particles contained in the absorbent body. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing the appearance of a diaper manufactured by a diaper manufacturing apparatus according to an embodiment. [Figure 2] FIG. 2 is an exploded perspective view of a diaper manufactured by the diaper manufacturing apparatus according to the embodiment. [Figure 3] FIG. 3 is a plan view of a diaper manufactured by the diaper manufacturing apparatus according to the embodiment. [Figure 4] FIG. 4 is a cross-sectional view of a diaper manufactured by the diaper manufacturing apparatus according to the embodiment. [Figure 5] FIG. 5 is a schematic view of a diaper manufacturing apparatus according to an embodiment. [Figure 6] FIG. 6 is a perspective view of the forming drum in the embodiment as viewed obliquely from above. [Figure 7] FIG. 7 is a schematic diagram of the SAP transport unit in the embodiment. [Figure 8] FIG. 8 is a diagram of a branch path provided on an inclined portion in the embodiment, viewed from above. [Figure 9] FIG. 9 is a top view of the outer circumferential surface of the forming drum and the branch passages in the embodiment. [Figure 10] FIG. 10 shows the pattern of SAP particles scattered on the mold. [Figure 11] FIG. 11 is a schematic diagram of a manufacturing apparatus according to a modified example. [Figure 12]FIG. 12 is a schematic diagram of a SAP transport unit in a modified example. [Figure 13] FIG. 13 is a top view of the outer peripheral surface of the forming drum and the branch passages in a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] The following describes an embodiment of the present invention. The embodiment described below is one aspect of the present invention and does not limit the technical scope of the present invention.

[0010] <Embodiment> In this embodiment, the longitudinal direction of a tape-type disposable diaper (an example of an "absorbent article" in the present application, hereinafter simply referred to as "diaper") is the direction connecting the front body portion facing the wearer's abdomen and the back body portion facing the back. A crotch section, which is positioned between the front body portion (one side in the longitudinal direction) and the back body portion (the other side in the longitudinal direction) (at the center in the longitudinal direction) and is located in front of the wearer's crotch (facing the crotch). When the diaper is worn by a wearer (hereinafter abbreviated as "worn state"), the side facing the wearer's skin (the inner side when worn) is the skin-facing side, and the side opposite the skin-facing side (the outer side when worn) is the non-skin-facing side. The thickness direction is the direction connecting the skin-facing side and the non-skin-facing side, and the width direction is the direction perpendicular to both the longitudinal direction and the thickness direction. A view from the thickness direction is referred to as a plan view. A diaper has a length along the longitudinal direction, which corresponds to the front-to-back direction of the wearer, and a length along the width direction, which is perpendicular to the longitudinal direction. Furthermore, terms relating to directions used in this application refer to directions that correspond to the front, back, left, and right of the wearer when worn. For example, the left-right direction in this application refers to the direction that corresponds to the left and right of the wearer when worn.

[0011] 1 is a perspective view of a diaper 1 manufactured by a diaper manufacturing apparatus according to an embodiment. The diaper 1 has a crotch region 1B, which corresponds to the crotch area that covers the wearer's genitals when worn, a front body region 1F located in front of the crotch region 1B and corresponding to the wearer's abdominal waist, and a back body region 1R located behind the crotch region 1B and corresponding to the wearer's back waist. The left and right edges of the back body region 1R are provided with front patches 2F, which have mechanical fasteners on the skin-facing side of the wearer and are looped on the non-skin-facing side of the front body region 1F, and tapes 2L1, 2L2, 2R1, and 2R2 that can be attached by the mechanical fasteners. When the tapes 2L1, 2L2, 2R1, and 2R2 are attached to the front patch 2F with the front body region 1F positioned on the wearer's ventral side and the back body region 1R positioned on the wearer's back, the diaper 1 is secured to the wearer's body, encircling the wearer's abdomen and thighs. Since the diaper 1 is secured to the wearer's body in this manner, the wearer can freely change positions while wearing the diaper 1. The non-skin-facing sides of the tapes 2L1, 2L2, 2R1, and 2R2 are looped, just like the non-skin-facing side of the front patch 2F. Therefore, the tapes 2L1, 2L2, 2R1, and 2R2 can be overlapped on the front patch 2F.

[0012] In order to prevent the formation of gaps between the diaper 1 and the wearer's skin that could serve as a liquid outflow path, the diaper 1 is provided with leg gathers 3AL, 3AR in areas along the wearer's leg circumference (thighs), leakage barrier walls 3L, 3R are provided on the inside of the leg gathers 3AL, 3AR in the width direction of the diaper 1, and waist gathers 3W are provided in areas along the wearer's abdominal circumference. The leg gathers 3AL, 3AR, leakage barrier walls 3L, 3R, and waist gathers 3W adhere to the wearer's skin by the elastic force of the elastic members. Therefore, liquid discharged from the wearer is easily absorbed through the diaper 1. The liquid is absorbed into the absorbent body 6 without leaking out. As the elastic member, thread-like or band-like rubber or the like can be appropriately selected.

[0013] Fig. 2 is an exploded perspective view of a diaper 1 manufactured by a diaper manufacturing apparatus according to an embodiment. Fig. 3 is a plan view of a diaper 1 manufactured by a diaper manufacturing apparatus according to an embodiment when stretched and viewed from the skin-facing side. Fig. 4 is a cross-sectional view of a diaper 1 manufactured by a diaper manufacturing apparatus according to an embodiment, taken along line AA in Fig. 3. In Fig. 4, each component is illustrated thicker than it actually is to make the internal structure of the diaper 1 easier to understand, but in reality, the diaper 1 is very thin.

[0014] The diaper 1 according to this embodiment has a narrow, gourd-like shape in plan view, with the front and back body regions 1F and 1R being wider than the crotch region 1B. This planar shape allows the diaper 1 to easily fit the wearer's abdomen and buttocks when worn. The planar shape of the diaper 1 is not limited to a gourd shape and may be, for example, a rectangular or battledore shape.

[0015] The diaper 1 is provided with a cover sheet 4 that forms the outer surface when worn. The cover sheet 4 is a sheet-like member having substantially the same planar shape (gourd-shaped) as the diaper 1, with constrictions 4KL, 4KR in the areas corresponding to the long sides. The cover sheet 4 forms the outer surface of the diaper 1, has sufficient rigidity to withstand friction with clothing, etc., and is provided to reinforce the back sheet 5 (described later) and improve the feel. The constrictions 4KL, 4KR are provided in the areas where the wearer's thighs are located. The cover sheet 4 is generally made of a nonwoven fabric made of synthetic fibers such as polypropylene, polyethylene, and polyethylene terephthalate. The cover sheet 4 is liquid-impermeable and moisture-permeable. The cover sheet 4 is not limited to a single-layer structure, but may be a multi-layer structure having an inner cover sheet and an outer cover sheet.

[0016] The diaper 1 comprises a back sheet 5, an absorbent body 6, and a top sheet 8, which are layered in this order on the wearer-facing surface of the cover sheet 4. The back sheet 5 and the top sheet 8 are all sheet-like members having a roughly rectangular appearance, and the absorbent body 6 is a mat-like member having a roughly gourd-like appearance. The back sheet 5, the absorbent body 6, and the top sheet 8 are all layered in this order on the cover sheet 4 with their longitudinal directions coinciding with the longitudinal direction of the cover sheet 4.

[0017] The backsheet 5 has a generally rectangular appearance. The backsheet 5 is made of a thermoplastic, water-impermeable resin such as polyethylene film to prevent leakage of excreted fluid that has flowed into the absorbent body 6. The backsheet 5 has water-repellent properties to prevent urine and moisture from seeping out of the diaper 1 and breathability to prevent the diaper 1 from becoming stuffy when worn. The backsheet 5 may be breathable by having many tiny ventilation holes formed therein.

[0018] The diaper 1 includes a top sheet 8 disposed on the skin-facing side when the diaper 1 is worn. The top sheet 8 is the part that comes into contact with the wearer's skin when the diaper 1 is worn, and is a water-permeable sheet made of a liquid-permeable material that allows liquids such as urine to pass through. The top sheet 8 may be made of a woven fabric, a nonwoven fabric, a porous film, or the like. The nonwoven fabric may be made of thermoplastic resin fibers such as polypropylene, polyethylene, polyester, or nylon that have been hydrophilized, or may be an air-through nonwoven fabric, a point-bonded nonwoven fabric, a spun-bonded nonwoven fabric, or a melt-blown nonwoven fabric.

[0019] An absorbent body 6 that absorbs fluid excreted by the wearer is disposed on the non-skin facing side of the top sheet 8. The longitudinal direction of the absorbent body 6 coincides with the longitudinal direction of the diaper 1.

[0020] The absorbent body 6 includes a crotch region 1B for absorbing and retaining fluids discharged by the wearer. The absorbent body 6 is disposed on the non-skin-facing side of the wrap sheet 8. In this embodiment, the absorbent body 6 has an absorbent core 6C containing an absorbent material and a core wrap sheet 7 that covers the entire absorbent core 6C. The longitudinal direction of the absorbent body 6 coincides with the longitudinal direction of the absorbent core 6C, the longitudinal direction of the core wrap sheet 7, and the longitudinal direction of the diaper 1.

[0021] The absorbent core 6C has an upper-layer absorbent mat 6A (an example of the "absorbent mat" referred to in this application) disposed on the top sheet 8 side, and a lower-layer absorbent mat 6B disposed on the non-skin-facing side. In plan view, the upper-layer absorbent mat 6A has a gourd shape with the front body region 1F and back body region 1R being wider than the crotch region 1B and the crotch region 1B being narrower. The lower-layer absorbent mat 6B is disposed below (non-skin-facing) the upper-layer absorbent mat 6A when viewed from the top sheet 8 side, and has a rectangular shape (oblong shape) whose long sides extend in the longitudinal direction of the diaper 1 in plan view. The upper-layer absorbent mat 6A and the lower-layer absorbent mat 6B are stacked in the thickness direction so that their respective widthwise centers are substantially aligned. In plan view, the upper-layer absorbent mat 6A is larger than the lower-layer absorbent mat 6B. The longitudinal direction of the absorbent body 6 coincides with the longitudinal directions of the upper and lower absorbent mats 6A, 6B and the diaper 1.

[0022] The crotch region 1B is sandwiched between the wearer's legs, so it is subjected to compressive pressure inward in the width direction. Meanwhile, in the front body region 1F and the back body region 1R, the wearer's weight exerts pressure in the thickness direction of the absorbent core 6C. To accommodate these pressures, the absorbent core 6C is provided with a constriction in the crotch region 1B. Furthermore, the upper-layer absorbent mat 6A and the lower-layer absorbent mat 6B are stacked to give the absorbent core 6C in the crotch region 1B a high basis weight. This prevents the absorbent core 6C from losing its shape inward in the width direction in the crotch region 1B. Furthermore, in the front body region 1F and the back body region 1R, the width of the absorbent core 6C is widened to increase the area on which the wearer's weight is applied, thereby preventing it from losing its shape in the thickness direction. For this reason, it is preferable to make the absorbent core 6C roughly gourd-shaped.

[0023] The absorbent core 6C has a structure in which granular absorbent resin (polymeric water-absorbing material) such as SAP (Super Absorbent Polymer), a hydrophilic polymer with a cross-linked structure that can absorb and retain water, is held in the gaps between short fibers of cellulosic fibers such as pulp, rayon, or cotton, or short fibers made from synthetic fibers such as polyethylene, polypropylene, or polyethylene terephthalate that have been hydrophilically treated. These short fibers and SAP are examples of absorbent materials.

[0024] In this embodiment, SAP particles refer to a granulated resin composition containing SAP. The term "SAP-containing resin composition" as used herein encompasses both a composition consisting solely of SAP and a composition containing SAP as the primary component, with other substances added to the extent that they do not adversely affect water absorption. Examples of "other substances" include additives such as surface modifiers added to hydrophobize the particle surface, and unreacted monomers remaining during the synthesis of SAP. SAP particles can absorb approximately 10 to 100 times their own weight in liquid. The SAP particles may be, for example, granular particles with a diameter of approximately 0.1 to 0.5 mm before absorbing liquid.

[0025] While SAP particles gel and can retain liquid, it takes a certain amount of time for the liquid to be absorbed. In diaper 1, the short fibers slow down the discharged liquid while diffusing it within the absorbent core 6C until the SAP particles have absorbed the liquid, allowing the discharged liquid to be absorbed by a wide range of SAP particles, thereby preventing the liquid from flowing back.

[0026] The absorbent core 6C may be disposed between the upper absorbent mat 6A and the lower absorbent mat 6B and may have a SAP layer formed of a large number of SAP particles. The absorbent core 6C diffuses liquids such as urine in the lower absorbent mat 6B and disperses the liquids in the SAP layer and the SAP contained in the upper absorbent mat 6A. The AP particles hold the liquid.

[0027] The core wrap sheet 7 is a water-permeable sheet that encases the entire absorbent core 6C, and more specifically, it covers the skin-facing side, non-skin-facing side, and side surfaces of the absorbent core 6C. The core wrap sheet 7 maintains the shape of the absorbent core 6C when not in contact with exudate liquid, preventing it from losing its shape and preventing the SAP particles contained in the upper absorbent mat 6A or lower absorbent mat 6B and the SAP particles contained in the SAP layer from escaping. Furthermore, SAP particles in an unabsorbed state resemble hard sand grains, and if these particles escape from the absorbent body 6 and come into direct contact with the wearer's skin, they may cause discomfort to the wearer. Therefore, the core wrap sheet 7 encases the absorbent core 6C, preventing it from losing its shape and preventing the SAP particles from escaping from the absorbent body 6.

[0028] In this embodiment, the core wrap sheet 7 is made of a pulp fiber sheet or a thin nonwoven fabric. In this embodiment, tissue paper is used for the core wrap sheet 7. The core wrap sheet 7 may be formed from two sheets: an upper-layer core wrap sheet (not shown) disposed between the upper-layer absorbent mat 6A and the top sheet 8, and a lower-layer core wrap sheet (not shown) disposed on the non-skin-facing side of the lower-layer absorbent mat 6B, covering the side of the absorbent core 6C and further covering the outer side in the width direction of the upper-layer core wrap sheet. When the core wrap sheet 7 is formed from two sheets, the upper-layer core wrap sheet and the lower-layer core wrap sheet may be formed from different materials. For example, the upper-layer core wrap sheet may be a pulp fiber sheet, and the lower-layer core wrap sheet may be a resin nonwoven fabric. The core wrap sheet 7 may also be formed from a single sheet.

[0029] The diaper 1 includes two grooves 6H in the absorbent body 6, each of which has a concave skin-facing side formed by reducing the amount of absorbent material forming the absorbent core 6C compared to portions other than the grooves 6H. The grooves 6H are located within the longitudinal length of the absorbent core 6C, with their front-to-rear ends located within the absorbent core 6C. The grooves 6H may be formed by compressing the absorbent body 6 in the thickness direction, or by penetrating the absorbent material forming the skin-facing side of the absorbent core 6C in the thickness direction. In this embodiment, the grooves 6H are formed in two parallel lines in the width direction, centered on the crotch region 1B, extending longitudinally of the absorbent core 6C. The grooves 6H are formed by compressing the absorbent core 6C, which is composed of an upper absorbent mat 6A and a lower absorbent mat 6B. Excreted fluids, such as urine, flow into the grooves 6H, move longitudinally along the grooves 6H, and are rapidly absorbed over a wide area of ​​the absorbent body 6 in the longitudinal direction. Therefore, the diaper 1 according to this embodiment is provided with the grooves 6H, which allows for rapid diffusion of excreted liquid. As shown in Fig. 3, the grooves 6H do not reach the longitudinal ends of the absorbent body 6. Therefore, excreted liquid that has migrated outward in the longitudinal direction does not reach the longitudinal ends of the absorbent body 6, but remains inside the grooves 6H and is gradually absorbed.

[0030] The two grooves 6H form valley folds when the diaper 1 is viewed from the skin-facing side, and when the diaper 1 is worn, the absorbent 6 is folded in a W-shape in the crotch region 1B when viewed from the skin-facing side. As a result, the widthwise central portion of the absorbent 6 sandwiched between the two grooves 6H rises convexly toward the skin-facing side and comes into contact with the wearer's skin. This allows the raised portion of the absorbent 6 to easily come into contact with the wearer's urethral opening, allowing it to effectively absorb and retain urine excreted from the urethral opening.

[0031] Furthermore, as excreted fluid is discharged from the wearer's urethral opening or anus, the excreted fluid tends to be discharged in the same place in the diaper 1, but there is a limit to the amount of excreted fluid that the absorbent body 6 can hold in the same place. The grooves 6H have the function of diffusing the excreted fluid discharged by the wearer in the longitudinal direction of the absorbent body 6, and the excreted fluid dispersed by the grooves 6H is absorbed in parts of the absorbent body 6 that have excess holding capacity. The provision of the grooves 6H allows urine to be absorbed throughout the entire diaper 1.

[0032] The back sheet 5, absorbent body 6, and top sheet 8 all extend from the front body region 1F to the back body region 1R. Therefore, when the wearer's genitals are covered with the cover sheet 4, in which the back sheet 5, absorbent body 6, and top sheet 8 are laminated, the longitudinal ends of the back sheet 5, absorbent body 6, and top sheet 8 are located on the wearer's ventral and dorsal sides. In other words, the wearer's genitals are covered by the absorbent body 6 from the wearer's ventral to dorsal sides. Therefore, whether the wearer is lying supine or prone, excreted fluid comes into contact with the absorbent body 6 via the top sheet 8.

[0033] The diaper 1 also includes a pair of water-impermeable side sheets 9L, 9R arranged on both widthwise sides of the diaper 1 on the skin-facing side and extending longitudinally. The side sheets 9L, 9R are arranged so that their longitudinal ends coincide with the longitudinal ends of the top sheet 8. The side sheets 9L, 9R have fixing regions 9LA, 9RA arranged on their outer widthwise sides. The fixing regions 9LA, 9RA are bonded to the top sheet 8, absorbent core 6, and back sheet 5, which are components arranged on the non-skin-facing side, with a hot melt adhesive.

[0034] The side sheets 9L, 9R are bonded to the top sheet 8 with hot melt adhesive. The widthwise inner edges of the hot melt adhesive form fold lines 3LL, 3LR (see FIG. 3), and the insides of the fold lines 3LL, 3LR form the upstanding leakage barrier walls 3L, 3R. That is, the fold lines 3LL, 3LR form the upstanding ends of the leakage barrier walls 3L, 3R. The widthwise inner edges of the side sheets 9L, 9R are free regions 9LB, 9RB that form the leakage barrier walls 3L, 3R. Near the ends of the free regions 9LB, 9RB, two rubber threads 3BL, 3BR, which are thread-like elastic members, are fixed with hot melt adhesive in a stretched state in the longitudinal direction of the diaper 1. The widthwise inner edges of the side sheets 9L, 9R are also bonded to the top sheet 8 near the longitudinal ends. However, the inside edges of the side sheets 9L, 9R are not bonded to the top sheet 8, allowing them to stand up toward the skin. When the elastic threads 3BL, 3BR contract, the leakage barrier walls 3L, 3R inside the fold lines 3LL, 3LR rise toward the skin, and the ends of the free regions 9LB, 9RB become the tips on the skin side. The rising leakage barrier walls 3L, 3R inhibit the movement of liquids and loose stools outward in the width direction of the leakage barrier walls 3L, 3R, thereby suppressing lateral leakage.

[0035] Substantially the entire longitudinal ends of the side sheets 9L, 9R at the fold lines 3LL, 3LR are bonded to the top sheet 8 with a hot melt adhesive, forming fixed portions 33L, 33R. The fixed regions 9LA, 9RA extend to both longitudinal ends of the side sheets 9L, 9R, so that the side sheets 9L, 9R are joined to the top sheet 8 over substantially the entire longitudinal ends. The absorbent body 6 is thick because it is constructed by laminating multiple absorbent mats, and providing the fixed portions 33L, 33R in areas overlapping the absorbent body 6 makes it difficult for the biasing force of the rubber threads 3BL, 3BR to be transmitted to the fixed portions 33L, 33R. Providing the fixed portions 33L, 33R in areas where the absorbent body 6 does not extend makes it easier for the fixed portions 33L, 33R to follow the biasing force of the rubber threads 3BL, 3BR.

[0036] The ends of the free regions 9LB, 9RB that are longitudinally outer than the areas where the rubber threads 3BL, 3BR are arranged can also be left unattached to the top sheet 8 at the fixed portions 33L, 33R. By not adhering the ends of the free regions 9LB, 9RB to the top sheet 8, the biasing force of the ends of the free regions 9LB, 9RB is transmitted gently throughout the entire area of ​​the fixed portions 33L, 33R, and it is possible to prevent the biasing force of the rubber threads 3BL, 3BR from concentrating on the longitudinal inside of the fixed portions 33L, 33R.

[0037] On the non-skin-facing side of the fold lines 3LL, 3LR, rubber threads 4LB, 4RB, which are thread-like elastic members, may be fixed in a state stretched in the longitudinal direction of the diaper 1 between the cover sheet 4 and the back sheet 5 with a hot melt adhesive, two for each thread in the width direction. The rubber threads 4LB and 4RB are elastic members for forming the leg gathers 3AL and 3AR shown in FIG. 1. The number of rubber threads 4LB and 4RB is not limited to two, but may be any number determined depending on the elastic force (contractile force) required in the design of the diaper 1. By arranging the rubber threads 4LB and 4RB in a stretched state, the contraction of the rubber threads 4LB and 4RB allows the diaper 1 to fit around the legs of the wearer.

[0038] The cover sheet 4 may be provided with rubber threads 4CL and 4CR along the longitudinal direction of the diaper 1, on the inner side of the rubber threads 4LB and 4RB in the width direction of the diaper 1, to prevent a gap from being formed between the diaper 1 and the abdominal circumference of the wearer. The rubber threads 4CL and 4CR are provided in accordance with the elastic force (contractile force) required for the design of the diaper 1. In this embodiment, three rubber threads 4CL and three rubber threads 4CR are provided.

[0039] Furthermore, a rubber thread 9ER for forming a waist gather 3W between the back sheet 5 and the top sheet 8 may be provided at a position further back than the end of the absorbent body 6. The rubber thread 9ER is provided between the back sheet 5 and the top sheet 8 with its longitudinal direction, which is the direction of stretch, oriented in the left-right direction of the diaper 1. Therefore, when the tapes 2L1, 2L2, 2R1, 2R2 provided on both the left and right sides of the rubber thread 9ER are attached to the front patch 2F on the abdominal side of the wearer, the rubber thread 9ER exerts a contractile force to tightly fit the diaper 1 to the wearer and prevent the formation of a gap between the diaper 1 and the wearer's abdominal circumference.

[0040] In addition, the regions extending widthwise outward of the fold lines 3LL, 3LR of the leakage barrier walls 3L, 3R in a plan view are the ear portions 10L, 10R. In this embodiment, the ear portions 10L, 10R are formed in the front body region 1F and the back body region 1R. The upper-layer absorbent mat 6A is positioned to include the widthwise outward of the free regions 9LB, 9RB. The diaper 1 can increase the amount of liquid absorption by increasing the cushioning properties of the ear portions 10L, 10R and by forming the upper-layer absorbent mat 6A large. The ear portions 10L, 10R may be formed in either the front body region 1F or the back body region 1R.

[0041] Next, a manufacturing apparatus and a manufacturing method for the diaper 1 according to this embodiment will be described with reference to FIG. 5. FIG. 5 is a schematic diagram showing a portion of the configuration of a manufacturing apparatus M for the diaper 1 according to this embodiment (an example of an "absorbent body manufacturing apparatus" as used herein; hereinafter abbreviated as "manufacturing apparatus M"). In this embodiment, the manufacturing apparatus M is a manufacturing apparatus for manufacturing the upper-layer absorbent mat 6A. Note that the manufacturing apparatus M is not limited to a manufacturing apparatus for the upper-layer absorbent mat 6A, but may also be used when manufacturing a lower-layer absorbent mat 6B in which SAP particles need to be distributed, or when manufacturing an SAP layer. Furthermore, the downward direction of the manufacturing apparatus M refers to the direction of gravity, and the direction opposite to the downward direction of the manufacturing apparatus M refers to the upward direction of the manufacturing apparatus M.

[0042] The manufacturing device M for manufacturing the upper absorbent mat 6A includes a pulp discharge section 11 that defibrates a pulp sheet and discharges the pulp, a pulp supply section 12 that supplies the pulp discharged from the pulp discharge section 11, a SAP supply section 13 that supplies SAP particles, and a forming drum 14 (an example of the "rotating body" as used herein) that sucks in the pulp and SAP particles and forms the upper absorbent mat 6A.

[0043] The pulp discharge unit 11 has a pulp crusher (not shown), and the pulp sheet formed from pulp fibers is defibrated by the pulp crusher and discharged to the pulp supply unit 12.

[0044] The pulp supply section 12 is provided below the pulp discharge section 11 and supplies the pulp that forms the upper absorbent mat 6A to the forming drum 14 by airflow. The pulp supply section 12 extends obliquely downward and is a duct with both ends in the MD direction open. The lower end of the pulp supply section 12 is arranged so as to cover a part of the forming drum 14, which will be described later. The pulp supply section 12 causes an air flow from the pulp discharge section 11 side toward the forming drum 14. Therefore, the pulp discharged from the pulp discharge section 11 is carried by the air flow along the pulp supply section 12 and supplied to the forming drum 14 provided below the pulp supply section 12. The CD direction of the pulp supply section 12 coincides with the width direction of the upper-layer absorbent mat 6A.

[0045] The SAP supply unit 13 has its lower end inserted into the pulp supply unit 12 from near the upper center, and extends obliquely downward within the pulp supply unit 12 toward the outer circumferential surface of the forming drum 14, supplying SAP particles to a form provided on the outer circumferential surface of the forming drum 14. Details of the SAP supply unit 13 will be described later.

[0046] The forming drum 14 is a hollow cylindrical rotating body having a formwork (an example of the "formwork" referred to in this application) on its outer periphery, and is provided so that its outer periphery is located below the pulp supply section 12 and the SAP supply section 13. The arc-shaped arrow Y1 in FIG. 5 indicates the rotation direction of the forming drum 14. The MD direction (rotation direction) of the forming drum 14 coincides with the longitudinal direction of the upper-layer absorbent mat 6A. The forming drum 14 has a central axis disposed in the CD direction and rotates in the direction of the arrow Y1 around this central axis as the rotation axis. In FIG. 5, the central axis of the forming drum 14 extends toward the depth of the drawing. The forming drum 14 may be rotated in the direction of the arrow Y1 by a drive unit (not shown) that receives power and drives a motor. The drive unit may be provided inside or outside the forming drum 14.

[0047] The forming drum 14 has a suction unit (not shown) that communicates with the formwork, which will be described later. The suction unit creates negative pressure inside by, for example, driving a suction fan, and sucks in outside air. The suction unit sucks pulp and SAP particles accumulated on the formwork into the interior of the forming drum 14. The suction unit may be provided inside the forming drum 14, or may be provided on one side of the forming drum 14. When the suction unit is provided on one side of the forming drum 14, it is connected from one side of the forming drum 14 to the formwork via the drive shaft of the forming drum 14 and the internal space of the forming drum 14.

[0048] 6 is a perspective view of the forming drum 14 seen from diagonally above. The bottom of a form 14C formed on the forming drum 14 is made of a porous member such as a metal mesh plate. That is, the bottom of the form 14C is breathable, and the negative pressure generated by the suction unit allows air outside the forming drum 14 to be sucked into the inside through the form 14C.

[0049] The form 14C is a form for forming the upper-layer absorbent mat 6A, and is formed along the entire outer periphery of the forming drum 14. The form 14C has the same roughly gourd shape as the upper-layer absorbent mat 6A. The form 14C may be formed directly on the outer periphery of the forming drum 14, or may be formed by attaching a form plate that is detachably configured to a cylindrical framework.

[0050] The form 14C has a convex portion 14CU that protrudes outward from the forming drum 14 in an area corresponding to the groove portion 6H and extends in the longitudinal direction of the form 14C. By providing the convex portion 14CU on the form 14C, the basis weight of the pulp or SAP particles deposited on the convex portion 14CU becomes lower than that of the surrounding area, and the groove portion 6H is formed.

[0051] With this configuration, in the deposition region R1, which is the region where the pulp supplying section 12 and the SAP supplying section 13 face the forming drum 14, the pulp particles supplied from the pulp supplying section 12 and the SAP particles supplied from the SAP supplying section 13 are sucked into the bottom side of the formwork 14C of the forming drum 14 together with the air sucked by the suction section. Although the pulp and SAP particles are sucked into the forming drum 14 through the bottom of the form 14C, they cannot pass through the porous member provided at the bottom of the form 14C and end up piling up inside the form 14C.

[0052] A diaper conveying path 15 is provided below the forming drum 14. The diaper conveying path 15 conveys the components constituting the diaper 1 in the direction of arrow Y2 in FIG. 5. The pulp and SAP particles accumulated within the mold 14C are conveyed to a transfer area R2 opposite the diaper conveying path 15 by the rotation of the forming drum 14. The pulp and SAP particles are then released as an upper absorbent mat 6A in the transfer area R2 and transferred to a component below the upper absorbent mat 6A in the absorbent body 6 flowing on the diaper conveying path 15. In this embodiment, the component below the upper absorbent mat 6A is a lower absorbent mat 6B. After the upper absorbent mat 6A is transferred in the transfer area R2, it is conveyed to the next process as an absorbent core 6C by the diaper conveying path 15. The MD direction of the diaper conveying path 15 coincides with the longitudinal direction of the upper absorbent mat 6A.

[0053] When manufacturing an upper-layer absorbent mat 6A containing SAP particles, it is necessary to deposit the SAP particles uniformly. If the SAP particles are not deposited uniformly, there is a risk that the amount of excreted fluid, such as urine, that is absorbed and retained by the upper-layer absorbent mat 6A will be uneven. Furthermore, uneven deposition of the SAP particles may cause the surface of the upper-layer absorbent mat 6A to become uneven, which may reduce comfort when worn.

[0054] Typically, SAP particles are supplied into the pulp supply section from above, and the pulp and SAP particles are mixed together in the pulp supply section before being supplied to the forming drum. However, the SAP particles are not discharged uniformly in the CD (cross-machine direction) from the SAP discharge section that discharges the SAP particles, and there is a risk that they may be discharged biased in the CD. Furthermore, SAP particles carried by the air flow in the pulp supply section 12 may fall downward due to gravity, making it difficult to disperse them uniformly within the pulp supply section 12.

[0055] Meanwhile, the manufacturing apparatus M according to this embodiment includes a SAP supply unit 13. The SAP supply unit 13 adjusts the distribution of SAP particles in each region of the upper-layer absorbent mat 6A where they are dispersed, and sends the particles to the forming drum 14. The SAP particles, whose distribution in each region of the upper-layer absorbent mat 6A has been adjusted by the SAP supply unit 13, are then directly supplied from the SAP supply unit 13 to the formwork 14C. This prevents the SAP particles from moving in the CD direction during transport, which would otherwise cause the SAP particles to accumulate unevenly on the upper-layer absorbent mat 6A. Furthermore, because the distribution of SAP particles accumulated on the upper-layer absorbent mat 6A can be adjusted, it is possible to intentionally create regions where SAP particles are not distributed or where there are few SAP particles, thereby forming grooves 6H in the upper-layer absorbent mat 6A.

[0056] 7 is a schematic diagram of the SAP supply section 13. The SAP supply section 13 has a SAP discharge section 13S that discharges SAP particles and an inclined section 13K that sends the SAP particles from the SAP discharge section 13S to the forming drum 14. The CD direction of the SAP supply section 13 coincides with the width direction of the upper-layer absorbent mat 6A.

[0057] The SAP discharge section 13S extends in the CD direction of the SAP supply section 13 as the longitudinal direction, has a substantially rectangular parallelepiped shape that is open on the side of the inclined section 13K, and discharges SAP particles into the inclined section 13K.

[0058] The SAP discharge section 13S is not limited to the above-mentioned shape as long as it can discharge SAP particles over the entire area of ​​the inclined section 13K in the CD direction. For example, the SAP discharge section 13S has a cylindrical shape with the CD direction of the SAP supply section 13 as the longitudinal direction, and the SAP discharge section 13S has a cylindrical shape with the CD direction of the SAP supply section 13 as the longitudinal direction. The SAP discharge section 13S may have a SAP supply port located therein and rotate in the MD. In this case, because the SAP discharge section 13S is rotating, SAP particles may be continuously discharged from the SAP supply port. Furthermore, the SAP particles discharged from the SAP discharge section 13S may be sent while being dispersed in the CD direction by a SAP dispersion section disposed between the lower end of the SAP discharge section 13S and the upper end of the inclined section 13K and inclined diagonally downward. For example, the SAP particles may be sent to the inclined section 13K in a state where they are dispersed in the CD direction by their own weight in the SAP dispersion section. The SAP particles used in this embodiment are preferably crushed SAP particles that are not perfectly spherical. Crushed SAP particles are easily entangled with pulp, making it less likely that the SAP will be unevenly distributed within the absorbent body 6. Furthermore, because the SAP particles are crushed, they are sent in the MD while being dispersed in the CD direction.

[0059] The inclined section 13K has a nozzle shape with its longitudinal direction aligned with the MD direction of the SAP supply section 13, and is inclined obliquely downward toward the forming drum 14. The inclined section 13K directs an airflow from the upper end side of the inclined section 13K toward the forming drum 14, and the airflow sends the SAP particles to the forming drum 14. The inclined section 13K may send the SAP particles by their own weight. Alternatively, the inclined section 13K may be open at the top, and the SAP particles may be sent to the forming drum 14 by an airflow flowing from the upper end side of the pulp supply section 12.

[0060] The inclined portion 13K is provided with a plurality of branch paths at the lower end of the inclined portion 13K, which are formed by branching out the flow path for sending SAP particles, and an adjustment door (an example of the "adjustment portion" as referred to in this application) for adjusting the distribution of the SAP particles passing through the plurality of branch paths.

[0061] FIG. 8 is a top view of the branch channel 13C provided in the inclined portion 13K. FIG. 8(A) shows the state in which the channel is open. The inclined portion 13K has, at its lower end, multiple wall portions 13W extending upward from the bottom surface of the lower side of the inclined portion 13K, forming branch channels 13C separated by the wall portions 13W. SAP particles delivered from the upper end of the inclined portion 13K pass through the inclined portion 13K in a state dispersed in the CD direction and are delivered to the branch channels 13C from the branch portion 13B, which is the branch point of the multiple branch channels 13C. At this time, the SAP particles dispersed in the CD direction are equally divided at the branch portion 13B, so that the distribution of SAP particles passing through each branch channel 13C is approximately the same. The SAP particles that have passed through the branch channels 13C are supplied to a mold 14C provided in the forming drum 14. The SAP particles supplied to the mold 14C are evenly distributed in the CD direction because they are equally divided at the branching section 13B so that the distribution of the SAP particles passing through each branching path 13C is approximately the same.

[0062] The provision of the branch paths 13C prevents the SAP particles from moving beyond the wall portions 13W in the CD direction, thereby preventing them from being unevenly distributed within the upper-layer absorbent mat 6A. Furthermore, because the branch paths 13C extend to the outer circumferential surface of the forming drum 14, the SAP particles passing through each branch path 13C can be distributed within the form 14C without varying their distribution. Therefore, the SAP particles that enter each branch path 13C are supplied to the forming drum 14 without varying their distribution, and the SAP particles are uniformly distributed within the form 14C.

[0063] Furthermore, branch paths 16C corresponding to each branch path 13C may be provided on the outer peripheral surface of the forming drum 14 (inside the formwork 14C). Fig. 9 is a top view of the outer peripheral surface of the forming drum 14 and the branch paths 13C. By providing the branch paths 16C inside the formwork 14C, it is possible to prevent the SAP particles from moving in the CD direction beyond the branch paths 16C while they are being transported by the forming drum 14, and to maintain a uniform distribution of the SAP particles in the CD direction in the branch paths 13C. This makes it possible to uniformly distribute the SAP particles in the upper-layer absorbent mat 6A.

[0064] Furthermore, it is possible to prevent SAP particles from being distributed in areas where they are not required. For example, when worn, both widthwise ends of the upper-layer absorbent mat 6A are in close contact with the wearer, and if the SAP particles hold a large amount of excreted liquid such as urine, they may be crushed by the wearer's body pressure, resulting in leakage of excreted liquid such as urine. Therefore, by preventing the distribution of SAP particles, it is possible to prevent leakage of excreted liquid such as urine. Therefore, it is possible to provide branch channels 16C so that SAP particles are not distributed at both widthwise ends of the upper-layer absorbent mat 6A.

[0065] The adjustment door 13A is provided on the wall 13W near the branching portion 13B and opens and closes the flow path of each branch path 13C to adjust the distribution of SAP particles entering each branch path 13C. The adjustment door 13A is approximately rectangular parallelepiped, and the adjustment door 13A and the wall 13W are connected by a hinge 13H. The adjustment door 13A rotates around the hinge 13H fixed to the wall 13W. FIG. 8(B) is a diagram showing a state in which the adjustment door 13A closes the flow path. As shown in FIG. 8(A), when the adjustment door 13A is arranged along the branch path 13C, the amount of SAP particles entering the branch path 13C is not limited. As shown in FIG. 8(B), when the adjustment door 13A blocks the start end of one branch path 13C, SAP particles are not sent to the branch path 13C whose start end is blocked. Therefore, by opening and closing the start of the branch path 13C with the adjustment door 13A, the distribution of SAP particles deposited on the upper-layer absorbent mat 6A can be adjusted, and upper-layer absorbent mats 6A with different distributions of SAP particles can be manufactured. For example, by not distributing SAP particles to form the grooves 6H, it is possible to form grooves 6H that are lower in volume than other areas. In this embodiment, as shown in FIG. 8(B), two adjustment doors 13A block the start of the branch path 13C, but one adjustment door 13A may block the start of the branch path 13C. Also, the start of multiple branch paths 13C may be blocked at the same time.

[0066] The adjusting door 13A may be connected to a motor (not shown), and the motor may be operated to open or close the branch path 13C. The motor may be operated by a switch provided outside the production line.

[0067] The adjustment doors 13A can adjust the distribution of SAP particles supplied into the formwork 14C. For example, when forming an area with a small amount of SAP particles in the upper-layer absorbent mat 6A, the distribution of SAP particles in the upper-layer absorbent mat 6A can be changed by opening and closing some of the adjustment doors 13A at regular intervals.

[0068] The adjusting door 13A may adjust the distribution of SAP particles supplied to each mold 14C to which SAP particles are supplied via the branching path 13C. That is, the timing of opening and closing the adjusting door 13A may be changed for each mold to which SAP particles are supplied via the branching path 13C. By changing the timing of opening and closing the adjusting door 13A for each mold to which SAP particles are supplied, it is possible to manufacture upper-layer absorbent mats 6A with different distributions of SAP particles.

[0069] For example, as shown in Fig. 10, the mold 14C may be divided into a plurality of grids, and the amount of SAP particles to be distributed in each grid region may be patterned, with the pattern being changed for each mold 14C. The solid areas in Fig. 10 indicate regions where SAP particles have not been dispersed.

[0070] The SAP supply unit 13 may be provided with a pulp supply unit 17 (see FIG. 8) that is open so as to communicate with the pulp supply unit 12. By providing the pulp supply unit 17, the pulp being transported by the pulp supply unit 12 is supplied into the SAP supply unit 13, so that the pulp and SAP particles can be transported to the forming drum 14 in a mixed state in the SAP supply unit 13. Furthermore, a door may be provided to close the pulp supply unit 17 when no pulp is supplied to the pulp supply unit 17, making it possible to change the mixing ratio of the pulp and SAP particles.

[0071] <Modification> A plurality of SAP supply units 13 may be provided facing the outer peripheral surface of the forming drum 14. For example, two SAP supply units 13 may be provided facing the outer peripheral surface of the forming drum 14. Fig. 11 is a schematic diagram showing a portion of the configuration of a manufacturing apparatus M according to a modified example. Fig. 12 is a schematic diagram of the SAP supply unit 13 in the modified example. The configuration of the manufacturing apparatus M other than the SAP supply unit 13 is the same as that of the embodiment.

[0072] The two SAP supply units 13 provided in the manufacturing apparatus M each have their lower ends inserted into the pulp supply unit 12 from near the upper center, and extend obliquely downward within the pulp supply unit 12 toward the outer circumferential surface of the forming drum 14, supplying SAP particles to a form 14C provided on the outer circumferential surface of the forming drum 14. In this modified example, the two SAP supply units 13 are arranged so as to be stacked one above the other within the pulp supply unit 12, and the SAP discharge unit 13S of the lower SAP supply unit 13 extends longer than the SAP discharge unit 13S of the upper SAP supply unit 13. The configuration of the SAP supply units 13 is the same as in the embodiment.

[0073] FIG. 13 is a top view of the outer circumferential surface of the forming drum 14 and the branch path 13C. By providing two SAP supply units 13, one above the other, the timing at which SAP particles are supplied to the outer circumferential surface of the forming drum 14 is increased. This allows for adjustment of the distribution of SAP particles deposited on the upper absorbent mat 6A. For example, a layer of pulp can be provided between layers of SAP particles. Furthermore, by closing the adjustment door 13A of the upper SAP supply unit 13 and limiting the amount of SAP particles supplied, it is possible to create an area where SAP particles that have passed through the branch path 13C located below are deposited, but where the amount of deposited SAP particles is smaller than in other areas.

[0074] The present invention is applicable not only to tape-type diapers but also to pants-type diapers and absorbent pads.

[0075] The features included in each of the embodiments and modifications thereof disclosed above can be combined with each other. [Explanation of symbols]

[0076] 1. Diapers 1F: Front body area 1B...Inseam area 1R: Back area 2F Front patch 2R･･Attached part 2L1, 2L2, 2R1, 2R2 tape 3W: Waist gather 3AL, 3AR Leg Gather 3L,3R·Leakage prevention wall 3LL, 3LR... Folded line 33L,33R・Fixed part 4. Cover sheet 4CL, 4CR, 3BL, 3BR, 4RB, 4LB, 9ER... Elastic thread 5. Back seat 6. Absorber 6C··Absorbent Core 6A··Upper layer absorbent mat 6B Lower layer absorbent mat 6H·Groove 7. Core wrap sheet 8. Top sheet 9L, 9R side seats 9LA,9RA·Fixed area 9LB,9RB・Free area 10L,10R・Ear part 11 Pulp discharge section 12 Pulp supply section 13...SAP Supply Department 13S...SAP discharge section 13K··Slope part 13C, 16C... Branching road 13A Adjustment door 13W...Wall part 13B Branch 14. Forming drum 14C··Formwork 15 Diaper transport path 17 Pulp supply section M·· Manufacturing Device

Claims

1. an SAP supply unit that supplies the SAP particles, the SAP supply unit having an inclined portion that slopes obliquely downward, a plurality of branch paths that are provided on the inclined portion and through which SAP particles of a superabsorbent polymer pass, and an adjusting unit that adjusts the distribution of the SAP particles passing through the plurality of branch paths; a hollow cylindrical rotor having a mesh-like form on its outer circumferential surface disposed opposite the lower end of the SAP supply unit, depositing an absorbent material containing the SAP particles supplied by the SAP supply unit on the form to form an absorbent mat constituting an absorbent body, and conveying the formed absorbent mat in the outer circumferential direction; Absorbent manufacturing equipment.

2. the adjusting unit adjusts the distribution of the SAP particles to be supplied into the mold. The apparatus for manufacturing the absorbent body according to claim 1.

3. a plurality of the formworks are provided on the rotating body, the adjusting unit adjusts the distribution of the SAP particles supplied to each mold form. The apparatus for manufacturing the absorbent body according to claim 1.

4. The SAP supply unit has a pulp supply unit capable of supplying pulp to the branch path. The apparatus for manufacturing an absorbent body according to any one of claims 1 to 3.

5. Two SAP supply units are provided facing each other on the outer circumferential surface of the rotating body. The apparatus for manufacturing an absorbent body according to any one of claims 1 to 3.

6. The absorbent body manufacturing apparatus according to any one of claims 1 to 3 is provided. Absorbent article manufacturing equipment.

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