Method for producing absorber

Abstract

To produce an absorber (SAP sheet) which can be made thin and has a high absorbent polymer with preferable fitness in wearing.SOLUTION: A method for producing an absorber including a high absorbent polymer, has: a transport step of supporting one surface of a substrate sheet by a support part, and transporting the substrate sheet; and a particle supply step of supplying high absorbent polymer particles toward the other surface of the substrate sheet. The support part has multiple openings, and in plan view, a diameter of an inscription circle inscribed to the openings is equal to or more than an average particle diameter of the high absorbent polymer particles. In the particle supply step, from the one surface side of the substrate sheet, the substrate sheet is sucked through the openings.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to a method for manufacturing an absorber.

Background Art

[0002] Conventionally, there have been absorbent articles such as disposable diapers provided with a liquid-absorbent absorber. As such an absorber, a SAP sheet containing a superabsorbent polymer (so-called SAP) and not containing a fibrous material such as pulp is known. Since such a SAP sheet is likely to have a smaller thickness compared to an absorber containing a fibrous material, it is suitable for forming a thin absorber. For example, Patent Document 1 discloses an absorber in which superabsorbent polymer particles are arranged on a sheet.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the SAP sheet (absorber) described in Patent Document 1, a large number of SAP particles are laminated on a material sheet (base material sheet) so as to have a uniform thickness. However, in such a SAP sheet, for example, when it is sandwiched between the wearer's legs (i.e., the crotch) during wearing, it is difficult to deform along the unevenness of the wearer's body, and there is a risk of deterioration in fit.

[0005] The present invention has been made in view of the above-described conventional problems, and an object thereof is to easily manufacture an absorber (SAP sheet) having a superabsorbent polymer with good fit during wearing while maintaining thinness.

Means for Solving the Problems

[0006] The main invention for achieving the above object is a method for manufacturing an absorber containing a superabsorbent polymer, the method including a conveying step of conveying a base sheet while supporting one surface of the base sheet by a support portion, and a particle supply step of supplying superabsorbent polymer particles toward the other surface of the base sheet, wherein the support portion has a plurality of openings, and in a plan view, a diameter of an inscribed circle inscribed in the openings is equal to or greater than an average particle diameter of the superabsorbent polymer particles, and in the particle supply step, the base sheet is sucked through the openings from a side of the one surface of the base sheet.

[0007] Other features of the present invention will be clarified by the description in this specification and the accompanying drawings.

Advantages of the Invention

[0008] According to the present invention, an absorber having a superabsorbent polymer with good fit during wearing can be easily manufactured while maintaining thinness.

Brief Description of the Drawings

[0009]

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DETAILED DESCRIPTION OF THE INVENTION

[0010] At least the following matters become clear from the description in this specification and the attached drawings.

[0011] (Aspect 1) A method for manufacturing an absorber containing a superabsorbent polymer, comprising: a conveying step of conveying the base sheet while supporting one surface of the base sheet by a support portion; and a particle supply step of supplying superabsorbent polymer particles toward the other surface of the base sheet, wherein the support portion has a plurality of openings, and in a plan view, a diameter of an inscribed circle inscribed in the openings is equal to or greater than an average particle diameter of the superabsorbent polymer particles, and in the particle supply step, the base sheet is sucked through the openings from a side of the one surface of the base sheet. A method for manufacturing an absorber, characterized by this.

[0012] According to Aspect 1, by having a conveying step of conveying the base sheet while supporting one surface of the base sheet by a support portion and a particle supply step of supplying superabsorbent polymer particles toward the other surface of the base sheet, an absorber having a superabsorbent polymer laminated on the base sheet can be manufactured. And, since the support portion has a plurality of openings and the base sheet is sucked through the plurality of openings from the side of the one surface of the base sheet in the particle supply step, an absorber in which a high basis weight region and a low basis weight region are formed around each high basis weight region can be manufactured. The absorber is easily deformed along the unevenness of the wearer's body because the low basis weight region serves as a folding starting point, and the fit is improved. In a plan view, since the diameter of the inscribed circle inscribed in each of the plurality of openings is equal to or greater than the average particle diameter of the superabsorbent polymer particles, a large number of high basis weight regions and low basis weight regions can be arranged while maintaining the thinness of the absorber. Therefore, according to Aspect 1, an absorber having a superabsorbent polymer with good fit during wearing can be easily manufactured while maintaining the thinness.

[0013] (Aspect 2) A method for manufacturing an absorber according to the method for manufacturing an absorber described in Aspect 1, wherein in the conveying step, the support portion is a conveying belt for conveying the base sheet. A method for manufacturing an absorber, characterized by this.

[0014] According to Aspect 2, even in an absorber manufacturing apparatus using a conveyor belt, an absorber having a highly absorbent polymer with good fit during wearing can be easily manufactured while maintaining its thinness.

[0015] (Aspect 3) A method for manufacturing an absorber according to Aspect 2, wherein a suction part is provided on the side opposite to the side where the base material sheet is located when viewed from the support part, and another conveyor belt having a suction opening is provided. The other conveyor belt is located between the conveyor belt and the suction part and moves in the same direction as the conveying direction of the conveyor belt. A method for manufacturing an absorber, characterized by this.

[0016] According to Aspect 3, since the other conveyor belt is located between the conveyor belt and the suction part and moves in the same direction as the conveying direction of the conveyor belt, wear of the conveyor belt due to the conveyor belt rubbing against the edge of the suction opening can be suppressed, and the conveyor belt can be made to have a longer service life.

[0017] (Aspect 4) A method for manufacturing an absorber according to Aspect 2 or 3, wherein a suction part is provided on the side opposite to the side where the base material sheet is located when viewed from the support part, and the suction port of the suction part includes a first opening region and a second opening region adjacent to the first opening region and having a lower opening ratio than the first opening region in an intersecting direction intersecting the conveying direction of the base material sheet. In the particle supply step, the suction part sucks the base material sheet from the side of the one surface of the base material sheet through the opening, the first opening region, and the second opening region. A method for manufacturing an absorber, characterized by this.

[0018] According to Aspect 4, an absorber having a channel region can be formed. In an absorber having a channel region, it becomes easier to deform in the width direction under the crotch of the wearer, the storage property under the crotch increases, and the fit is further improved.

[0019] (Aspect 5) A method for manufacturing the absorber according to Aspect 4, characterized in that the aperture ratio of the first aperture region is equal to or greater than the aperture ratio of the apertures in the region of the support portion where the apertures are provided. A method for manufacturing an absorber.

[0020] According to Aspect 5, an absorber having a channel region can be appropriately formed.

[0021] (Aspect 6) A method for manufacturing the absorber according to Aspect 4, characterized in that the aperture ratio of the second aperture region is equal to or less than the aperture ratio of the apertures in the region of the support portion where the apertures are provided. A method for manufacturing an absorber.

[0022] According to Aspect 6, an absorber having a channel region can be appropriately formed.

[0023] (Aspect 7) A method for manufacturing the absorber according to Aspect 4, characterized in that a plurality of the second aperture regions are provided in the intersecting direction. A method for manufacturing an absorber.

[0024] According to Aspect 7, an absorber having a plurality of channel regions can be formed. In an absorber having a plurality of channel regions, the storage property in the crotch is further increased and the fit is further improved.

[0025] (Aspect 8) A method for manufacturing the absorber according to Aspect 4, wherein the suction part includes a third opening region and a non-opening region, the third opening region is located downstream of the first opening region in the conveying direction, and has a portion overlapping the first opening region in the intersecting direction, the third opening region has a lower opening ratio than the first opening region, the non-opening region is located downstream of the second opening region in the conveying direction, and has a portion overlapping the second opening region in the intersecting direction, and the suction part sucks the base material sheet from the side of one surface of the base material sheet through the third opening region downstream of the position where the superabsorbent polymer particles are supplied to the base material sheet. A method for manufacturing an absorber, characterized by the above.

[0026] According to Aspect 8, it is possible to suppress the superabsorbent polymer particles rebounded at the position where the superabsorbent polymer particles are supplied from being arranged in the channel region on the downstream side.

[0027] (Aspect 9) A method for manufacturing the absorber according to Aspect 8, wherein the suction part includes a fourth opening region provided at a position overlapping the end portion of the base material sheet in the intersecting direction outside the first opening region and the third opening region in a plan view. In the conveying step, the suction part sucks the end portion from the side of one surface of the base material sheet through the fourth opening region. A method for manufacturing an absorber, characterized by the above.

[0028] According to Aspect 9, it is possible to suppress the curling up of the base material sheet during conveyance.

[0029] (Aspect 10) A method for manufacturing the absorber according to Aspect 1, wherein in the conveying step, the support part is a rotating body that conveys the base material sheet. A method for manufacturing an absorber, characterized by the above.

[0030] According to Aspect 10, even in an absorber manufacturing apparatus using a rotating body, an absorber having a highly absorbent polymer with good fit during wearing can be easily manufactured while maintaining its thinness.

[0031] (Aspect 11) A method for manufacturing an absorber according to Aspect 10, wherein a suction part is provided on the side opposite to the side where the base material sheet is located when viewed from the support part, the support part includes a first opening and a second opening having a lower opening ratio than the first opening among the plurality of openings, in the crossing direction intersecting with the conveyance direction of the base material sheet, the region where the first opening is provided and the region where the second opening is provided are arranged adjacent to each other, and in the particle supply step, the suction part sucks the base material sheet from the side of one surface of the base material sheet through the first opening and the second opening. A method for manufacturing an absorber.

[0032] According to Aspect 11, an absorber having a channel region can be formed. In an absorber having a channel region, it is easier to deform in the width direction under the crotch of the wearer, the storage property under the crotch is increased, and the fit is further improved.

[0033] (Aspect 12) A method for manufacturing an absorber according to Aspect 11, wherein a plurality of regions where the second opening is provided are provided in the crossing direction. A method for manufacturing an absorber.

[0034] According to Aspect 12, an absorber having a plurality of channel regions can be formed. In an absorber having a plurality of channel regions, the storage property under the crotch is further increased, and the fit is further improved.

[0035] (Aspect 13) A method for manufacturing an absorber according to Aspect 1, having an upstream adhesive application step of applying an adhesive toward the other surface of the base material sheet on the upstream side in the conveyance direction of the base material sheet with respect to the position where the highly absorbent polymer particles are supplied to the base material sheet. A method for manufacturing an absorber.

[0036] According to Aspect 13, the highly absorbent polymer particles can be easily attached to the base sheet.

[0037] (Aspect 14) A method for manufacturing the absorber according to Aspect 13, comprising: a separate sheet supply step of supplying a separate sheet from the other surface side of the base sheet so as to cover the highly absorbent polymer particles on the downstream side in the conveyance direction of the base sheet from the position where the highly absorbent polymer particles are supplied to the base sheet; and a joint portion forming step of joining the separate sheet and the base sheet in the thickness direction along an intersection direction intersecting the conveyance direction of the base sheet in a region where the adhesive is not applied on the other surface of the base sheet. A method for manufacturing an absorber, characterized by having the above steps.

[0038] According to Aspect 14, the opening between the base sheet and the separate sheet can be suppressed.

[0039] (Aspect 15) A method for manufacturing the absorber according to Aspect 1, characterized in that the diameter of the inscribed circle inscribed in the opening is 2 mm or more and 4 mm or less. A method for manufacturing an absorber.

[0040] According to Aspect 15, by reducing the size of each of the plurality of high basis weight regions in plan view, a large number of high basis weight regions and low basis weight regions can be arranged on the base sheet, and the absorber can be easily deformed along the unevenness of the wearer's body, improving the fit.

[0041] (Aspect 16) A method for manufacturing the absorber according to Aspect 15, characterized in that in the support portion, the opening ratio of the opening in the region where the opening is provided is 40% or more and 60% or less. A method for manufacturing an absorber.

[0042] According to Aspect 16, a high basis weight region can be appropriately formed in the absorber.

[0043] (Aspect 17) A method for manufacturing the absorber according to Aspect 1, comprising a downstream adhesive discharge step of discharging an adhesive together with an air flow toward the other surface of the base sheet on the downstream side in the conveyance direction of the base sheet from the position where the superabsorbent polymer particles are supplied to the base sheet, and at least a part of the superabsorbent polymer particles rebounded from the base sheet is pushed back toward the base sheet side by the discharged adhesive. A method for manufacturing an absorber, characterized in that.

[0044] According to Aspect 17, it is possible to reduce the arrangement of superabsorbent polymer particles at unintended positions on the base sheet.

[0045] (Aspect 18) A method for manufacturing the absorber according to Aspect 17, characterized in that, in the conveyance step, the base sheet is conveyed by a conveyance conveyor, and the conveyance surface of the conveyance conveyor is inclined such that the downstream side faces downward with respect to the horizontal plane. A method for manufacturing an absorber.

[0046] According to Aspect 18, it is possible to further reduce the arrangement of superabsorbent polymer particles at unintended positions on the base sheet.

[0047] (Aspect 19) A method for manufacturing the absorber according to Aspect 17, characterized in that, in the conveyance step, the base sheet is conveyed by a rotating body, the adhesive is discharged in a predetermined discharge direction, and the upstream side in the discharge direction is inclined toward the downstream side in the conveyance direction such that the angle formed by an imaginary line extending the discharge direction and the tangent of the rotating body at the intersection of the imaginary line and the outer peripheral surface of the rotating body is greater than 90 degrees. A method for manufacturing an absorber.

[0048] According to Aspect 19, it is possible to reduce the arrangement of superabsorbent polymer particles at unintended positions on the base sheet.

[0049] (Aspect 20) A method for manufacturing the absorber according to Aspect 1, characterized in that, on the downstream side in the conveyance direction of the base sheet with respect to the position where the superabsorbent polymer particles are supplied to the base sheet, there is a fibrous material supply step of supplying a fibrous material containing pulp from above the superabsorbent polymer laminated on the base sheet. A method for manufacturing an absorber.

[0050] According to Aspect 20, an absorber that can quickly temporarily absorb excreted liquid and suppress overflow and leakage of excreted liquid during excretion can be easily manufactured.

[0051] ===Absorbent article and absorber=== As an absorbent article according to the present invention, a pant-type disposable diaper 1 for infants (hereinafter also referred to as "diaper 1") will be described as an example. However, the absorbent articles according to the present invention include tape-type disposable diapers, short-type napkins, absorbent pads, sanitary napkins, and other absorbent articles. Further, the wearer of the absorbent article is not limited to infants, and may be a living organism such as an adult or an animal.

[0052] <<Configuration of absorbent article (diaper 1)>> FIG. 1 is a schematic perspective view of diaper 1. FIG. 2 is a plan view of diaper 1 in a deployed and stretched state as viewed from the skin side. FIG. 3 is a schematic cross-sectional view taken along the center line CL of FIG. 2.

[0053] The "deployed state" of diaper 1 means a state in which a pair of side joints 2 provided on both sides of diaper 1 shown in FIG. 1 are separated and diaper 1 is opened and flattened as shown in FIG. 2. The "stretched state" of diaper 1 means a state in which the entire diaper 1 is stretched without wrinkles. Specifically, it means a state in which the dimensions of each member constituting diaper 1 (for example, the absorbent main body 10, the waist portions 30, 40, etc. described later) are extended until they match or are close to the dimensions of the member alone.

[0054] As shown in FIG. 1, the diaper 1 has an up-down direction, a width direction, and a front-back direction that are orthogonal to each other, and has a waist opening BH and a pair of leg openings LH. The upper side in the up-down direction corresponds to the side of the waist opening BH, and the lower side corresponds to the crotch side. The front side in the front-back direction corresponds to the ventral side of the wearer, and the rear side corresponds to the dorsal side of the wearer. The width direction is a direction along the expansion and contraction direction of the waist elastic members 33 and 43 such as thread rubber provided on the front waist portion 30 and the rear waist portion 40 as shown in FIG. 2. The up-down direction is a direction along an orthogonal direction orthogonal to the expansion and contraction direction.

[0055] The diaper 1 is a so-called three-piece type pant diaper having a liquid-absorbent absorbent body 10 and a pair of waist portions 30 and 40. Among the pair of waist portions, the one that covers the ventral side portion of the wearer is also referred to as the front waist portion 30, and the one that covers the dorsal side portion of the wearer is also referred to as the rear waist portion 40.

[0056] In the unfolded state shown in FIG. 2, the diaper 1 has a longitudinal direction, a width direction, and a thickness direction that are orthogonal to each other. The longitudinal direction is along the longitudinal direction of the absorbent body 10 and along the up-down direction of the pant diaper 1. The thickness direction is the direction in which the materials constituting the diaper 1 are laminated as shown in FIG. 3. The side in contact with the skin of the wearer in the thickness direction is the skin side, and the opposite side is the non-skin side.

[0057] Also, in the unfolded state of FIG. 2, the front waist portion 30 and the rear waist portion 40 are arranged in parallel with a space in the longitudinal direction, and the absorbent body 10 is stretched between them. Each end in the longitudinal direction of the absorbent body 10 is joined and fixed to the skin side of the nearest waist portions 30 and 40, and the external shape forms a substantially H shape in plan view. Then, from this state, it is folded in half along the center line CL in the longitudinal direction of the absorbent body 10. In this folded state, the front waist portion 30 and the rear waist portion 40 facing each other are joined and connected at the side portions on both sides in the width direction, and a pair of side joints 2 are formed. The side joints 2 are formed by known joining means such as welding and adhesion.

[0058] As shown in FIG. 3, the absorbent body 10 has an absorber 20 (details will be described later), a liquid-permeable topsheet 12 disposed closer to the skin side than the absorber 20, and a backsheet 13 disposed closer to the non-skin side than the absorber 20. The backsheet 13 has a two-layer structure including a liquid-impermeable sheet 13a and a hydrophobic outer sheet 13b disposed on the non-skin side thereof. However, the absorbent body 10 may be provided with other sheet members. For example, a second sheet (not shown) may be provided between the topsheet 12 and the absorber 20 in the thickness direction.

[0059] A pair of leak-preventing wall portions 15 are provided along the longitudinal direction of the absorbent body 10 on both side portions in the width direction of the absorbent body 10. In FIG. 3, in the width direction, a part of the outer sheet 13b extends outside both ends of the absorber 20 and is bent at a plurality of locations on the skin side, thereby forming a pair of leak-preventing wall portions 15. A leak-preventing wall elastic member 16 such as a thread rubber is attached to the tip end portion of the leak-preventing wall portion 15 in a state of being stretched along the longitudinal direction of the absorbent body 10, and the leak-preventing wall portion 15 is configured to be able to stand up on the skin side. Further, leg-around elastic members 17 such as thread rubber are attached to both side portions in the width direction of the absorbent body 10 in a state of being stretched along the longitudinal direction of the absorbent body 10.

[0060] As shown in FIG. 2, the front body-around portion 30 and the rear body-around portion 40 each have a skin-side sheet 31, 41, a non-skin-side sheet 32, 42, and a plurality of body-around elastic members 33, 43 such as thread rubber. The plurality of body-around elastic members 33, 43 are arranged side by side in the vertical direction between the skin-side sheet 31, 41 and the non-skin-side sheet 32, 42 and are attached in a state of being stretched in the width direction. Due to the elasticity of the body-around elastic members 33, 43, the front body-around portion 30 and the rear body-around portion 40 fit around the wearer's body. Further, cover sheets 34, 44 may be provided so as to cover the upper end portion of the absorbent body 10 from the skin side. The cover sheets 34, 44 can suppress the opening of the absorbent body 10 and the like.

[0061] Also, as shown in Fig. 2, the planar shapes of the front torso wrap portion 30 and the rear torso wrap portion 40 in the deployed and extended state are different. The front torso wrap portion 30 has a length in the vertical direction that is approximately the same as that of the side joint portion 2 and is rectangular in shape, being long in the width direction. The rear torso wrap portion 40 has a rectangular portion that overlaps with the front torso wrap portion 30 and a substantially trapezoidal portion 40E that extends downward therefrom. The extending portion 40E can cover the wearer's buttocks.

[0062] The basic configuration of the diaper 1 has been described above, but the above configuration is an example and is not limited thereto. For example, the front torso wrap portion 30 and the rear torso wrap portion 40 may be formed of a single continuous member, or an outer member for the crotch portion that connects the front torso wrap portion 30 and the rear torso wrap portion 40 may be provided. Also, elastic members such as the torso elastic members 33 and 43 may be sheet-like elastic members instead of thread rubber.

[0063] <<Configuration of Absorbent Body>> Next, details of the absorbent body 20 of the above-described absorbent article (diaper 1) will be described based on Figs. 4A, 4B, and 5.

[0064] Fig. 4A is a schematic cross-sectional view of the absorbent body 20. Fig. 4B is a schematic cross-sectional view of the absorbent body 20A showing details of the SAP layer 27. Fig. 5 is a schematic plan view of the absorbent body 20A.

[0065] As shown in Fig. 4A, the absorbent body 20 of the above-described absorbent article (diaper 1) has absorbent cores 21 to 23 between the skin-side core wrap sheet 24 and the non-skin-side core wrap sheet 25. Each of the absorbent cores 21 to 23 is a member that absorbs and holds excreted liquids such as urine and contains at least one of a fibrous material and a super absorbent polymer (hereinafter also referred to as SAP).

[0066] The fibrous material and the superabsorbent polymer are not particularly limited as long as they can be used as the absorbent core of the absorbent article. The fibrous material is a fibrous material having liquid absorbency, and examples thereof include wood pulp fibers, non-wood pulp fibers such as bagasse, kenaf, bamboo, hemp, cotton, etc., regenerated cellulose fibers such as rayon fibers, semi-synthetic fibers such as acetate fibers, etc., or mixtures thereof. Examples of the SAP include starch-based, cellulose-based, synthetic polymer-based polymer absorbents, or mixtures thereof. Further, the core wrap sheets 24 and 25 are liquid-permeable sheets, and examples thereof include non-woven fabrics and tissues.

[0067] The absorbent cores 21 to 23 may be referred to as the skin-side layer 21, the intermediate layer 22, and the non-skin-side layer 23 in order from the skin side in the thickness direction. In the absorber 20 shown in FIG. 4A, the skin-side layer 21 is not integrally formed with the intermediate layer 22 located on the non-skin side of the skin-side layer 21, and is laminated adjacent to the intermediate layer 22 in the thickness direction via a sheet 26 formed of a non-woven fabric, a tissue, or the like. Further, in the absorber 20 shown in FIG. 4A, the intermediate layer 22 and the non-skin-side layer 23 are integrally formed. That is, the non-skin-side layer 23 is directly laminated on the non-skin side of the intermediate layer 22 without passing through a sheet such as a non-woven fabric or an adhesive HMA.

[0068] The volume occupancy rate of the fibrous material or SAP in the absorbent cores 21 to 23 can be changed for each of the absorbent cores 21 to 23 according to the purpose. For example, the volume occupancy rate of SAP may be high in the skin-side layer 21, the volume occupancy rate of the fibrous material may be high in the intermediate layer 22, and the volume occupancy rate of SAP may be high in the non-skin-side layer 23. Further, the skin-side layer 21 may have only SAP without having a fibrous material, the intermediate layer 22 may have only a fibrous material without having SAP, and the non-skin-side layer 23 may have only SAP without having a fibrous material. Since the absorption rate of SAP for liquid is slow and the absorption rate of the fibrous material for liquid is faster than that of SAP, the excreted liquid is likely to migrate to the intermediate layer 22 before being absorbed by the SAP in the skin-side layer 21. Then, the excreted liquid absorbed between the fibers of the fibrous material in the intermediate layer 22 gradually migrates to the non-skin-side layer 23 by gravity and is firmly absorbed and held by the SAP in the non-skin-side layer 23.

[0069] This makes it easier to draw the excreted liquid into the non-skin side layer 23, and the absorbent cores 21 to 23 can be effectively utilized in the thickness direction. Therefore, the water absorption and retention capacity of the absorbent cores 21 to 23 is increased, and leakage of the excreted liquid can be suppressed even when repeated excretion occurs. In addition, the dryness of the skin side surface of the absorbent cores 21 to 23 is ensured, and the wearing comfort of the diaper 1 is improved. Further, when the excreted liquid in the intermediate layer 22 or the non-skin side layer 23 attempts to return to the skin side, the SAP in the skin side layer 21 absorbs and retains the excreted liquid. Therefore, rewetting of the excreted liquid can be suppressed. From this point as well, the dryness of the skin side surface of the absorbent cores 21 to 23 is ensured.

[0070] As shown in FIG. 4A, in the thickness direction, a sheet 26 is located closer to the skin side (the side where the skin side layer 21 is located) than the intermediate layer 22, and an adhesive HMA is provided between the intermediate layer 22 and the sheet 26. Here, the adhesive HMA is a hot melt adhesive. In other words, the adhesive HMA is provided between the fibrous material (intermediate layer 22) and the SAP (skin side layer 21). Further, a core wrap sheet 25 is located on the non-skin side of the non-skin side layer 23, and an adhesive HMA is provided between the non-skin side layer 23 and the core wrap sheet 25. The adhesive HMA provided between the intermediate layer 22 and the sheet 26 and the adhesive HMA provided between the non-skin side layer 23 and the core wrap sheet 25 join the sheet 26 and the core wrap sheet 25 and fix the intermediate layer 22 and the non-skin side layer 23 to the sheet 26 and the core wrap sheet 25.

[0071] Here, the absorber 20 is not limited to the embodiment shown in FIG. 4A. In the absorber 20 shown in FIG. 4A, in order from the skin side in the thickness direction, there are a sheet (core wrap sheet 24), a skin side layer 21, a sheet 26, an integrally formed intermediate layer 22 and a non-skin side layer 23, and a sheet (core wrap sheet 25) laminated in this order. However, the sheet 26 may be located between the intermediate layer 22 and the non-skin side layer 23 instead of between the skin side layer 21 and the intermediate layer 22. In this case, the skin side layer 21 (the layer with a high volume occupancy rate of SAP) and the intermediate layer 22 (the layer with a high volume occupancy rate of fibrous material) may be integrally formed. That is, the intermediate layer 22 (the layer with a high volume occupancy rate of fibrous material) may be directly laminated on the non-skin side of the skin side layer 21 (the layer with a high volume occupancy rate of SAP) without passing through a sheet such as a non-woven fabric or an adhesive HMA. In this case, the absorber 20 has a fibrous material containing pulp at a position adjacent to SAP in the thickness direction. Thereby, the excreted liquid can be quickly temporarily absorbed, and the overflow and leakage of the excreted liquid during excretion can be suppressed. And the non-skin side layer 23 (the layer with a high volume occupancy rate of SAP) may be laminated adjacent in the thickness direction via the sheet 26.

[0072] Furthermore, not limited to the above, the skin side layer 21 not integrally formed with the intermediate layer 22 may be laminated with the intermediate layer 22 without passing through a sheet such as a non-woven fabric or an adhesive HMA. Similarly, the non-skin side layer 23 not integrally formed with the intermediate layer 22 may be laminated with the intermediate layer 22 without passing through a sheet such as a non-woven fabric or an adhesive HMA. Furthermore, the intermediate layer 22 is not limited to being integrally formed with only one of the skin side layer 21 and the non-skin side layer 23, and may be integrally formed with both the skin side layer 21 and the non-skin side layer 23. A sheet such as a non-woven fabric or an adhesive HMA may or may not be provided between the skin side layer 21 and the intermediate layer 22, and between the intermediate layer 22 and the non-skin side layer 23.

[0073] The absorber 20 is not limited to the mode in which three absorbent cores of the skin-side layer 21, the intermediate layer 22, and the non-skin-side layer 23 are laminated. The absorbent cores may be laminated in two layers, or only one absorbent core may be laminated. Hereinafter, as an aspect of only one absorbent core, the description will continue using an absorber in which SAP is laminated on a sheet such as a non-woven fabric (hereinafter referred to as an SAP sheet).

[0074] As shown in FIG. 4B, the absorber 20A has a base sheet 14, an SAP layer 27, and another sheet 14S. The combination of the base sheet 14 and the SAP layer 27 and another sheet 14S in the absorber 20A corresponds to, for example, the combination of the core wrap sheet 24, the skin-side layer 21, and the sheet 26 in the above description, or the combination of the core wrap sheet 25, the non-skin-side layer 23, and the sheet 26 when the sheet 26 is positioned between the intermediate layer 22 and the non-skin-side layer 23. Here, the SAP layer 27 (the high basis weight region 211 and the low basis weight region 212 described later) has only SAP and does not contain fibrous materials other than SAP. Thereby, a thinner absorber 20A can be formed as compared with an absorber containing fibrous materials. The SAP in the SAP layer 27 is fixed to the base sheet 14 and another sheet 14S by the adhesive HMA. Thereby, the fixing of the SAP to the base sheet 14 and another sheet 14S can be surely performed.

[0075] Here, in the following description, the "particles" when used together with the term "superabsorbent polymer (SAP)" include any individual shape or form, and the "particles" can include granules, aggregates, flakes, fibers, spheres, etc., and combinations thereof. Further, the particles can have any desired shape, such as spherical, polygonal, rod-shaped, polyhedral, or other regular or irregular forms of circular or angular shapes.

[0076] As shown in FIG. 4B, the SAP layer 27 has a high basis weight region 211 where the basis weight of the SAP is higher than that of the surroundings. Then, as shown in FIG. 5, among the high basis weight regions 211, the point S where the maximum thickness in the thickness direction is located intermittently in the longitudinal direction and the width direction. As a result, the high basis weight regions 211 shown in FIG. 5 are arranged intermittently in the longitudinal direction and the width direction. Further, a low basis weight region 212 where the basis weight of the SAP is lower than that of the high basis weight region 211 is formed between adjacent points S having the maximum thickness (that is, around the high basis weight region 211).

[0077] However, if the point S having the maximum thickness is located intermittently in the longitudinal direction and the width direction, a part of the space between adjacent points S having the maximum thickness may be formed by the high basis weight region 211. That is, a part of the space between adjacent points S having the maximum thickness may be connected by the high basis weight region 211. In FIG. 5, the range of the high basis weight region 211 in plan view is represented by a solid line, and the range of the low basis weight region 212 is represented by a dashed-dotted line. The ranges of the high basis weight region 211 and the low basis weight region 212 shown in FIG. 5 are schematically represented for convenience.

[0078] As shown in FIGS. 4B and 5, the low basis weight region 212 has a low basis weight laminated region 212E where the SAP is laminated and a non-laminated region 212N where there is no SAP. Here, "there is no SAP" includes not only the meaning that there are no SAP particles, but also that there are very few laminated SAP particles and substantially no SAP particles. In FIG. 5, a △ mark is attached to the center of the low basis weight laminated region 212E, and a × mark is attached to the center of the non-laminated region 212N.

[0079] In the absorber 20A of the present embodiment, the low basis weight region 212 (the low basis weight laminated region 212E and the non-laminated region 212N) serves as a folding starting point, making it easier to deform along the unevenness of the wearer's body and improving the fit. Further, as the low basis weight region 212 serving as the folding starting point, it has a low basis weight laminated region 212E that can absorb and hold excreted liquid, and a non-laminated region 212N that is more easily bent due to the absence of SAP. Thereby, even in the low basis weight region 212 where the basis weight of SAP is lower than that of the high basis weight region 211, it is possible to achieve both ease of deformation along the unevenness of the wearer's body and the absorption and holding power of excreted liquid.

[0080] As described above, the low basis weight region 212 is formed between the points S having the maximum thickness that are intermittently arranged in the longitudinal direction and the width direction. For this reason, the low basis weight region 212 is also intermittently arranged in the longitudinal direction and the width direction as shown in FIG. 5. That is, the low basis weight laminated region 212E is intermittently arranged in the longitudinal direction and the width direction, and similarly, the non-laminated region 212N is also intermittently arranged in the longitudinal direction and the width direction. In the absorber 20A, since the low basis weight laminated region 212E and the non-laminated region 212N are arranged sparsely in a planar manner in this way, it is possible to have ease of deformation along the unevenness of the wearer's body and the absorption and holding power of excreted liquid with a planar spread.

[0081] In the absorber 20A of the present embodiment, for example, in the plan view shown in FIG. 5, the number of low basis weight laminated regions 212E is different in each region obtained by trisecting the absorber 20A in the longitudinal direction. Also, the number of non-laminated regions 212N is different in each region obtained by trisecting the absorber 20A in the longitudinal direction. Although details will be described later, when manufacturing the absorber by supplying SAP particles toward the base sheet, the region where the SAP particles did not adhere becomes the non-laminated region 212N, and the region where some SAP particles adhered becomes the low basis weight laminated region 212E. Since each of the non-laminated region 212N and the low basis weight laminated region 212E occurs randomly in a plane, as described above, in the plan view, the number of low basis weight laminated regions 212E and the number of non-laminated regions 212N are different in each region obtained by trisecting the absorber 20A in the longitudinal direction. Thus, by arranging the low basis weight laminated region 212E and the non-laminated region 212N randomly in a plane, the absorber 20A can be easily deformed along the unevenness of the wearer's body, and the fit can be improved.

[0082] Furthermore, in the absorber 20A of the present embodiment, by having the low basis weight region 212 around the high basis weight region 211, the excreted liquid is likely to diffuse in the plane direction. If the basis weight of the SAP is constant in a plane, when adjacent SAPs absorb moisture, they are likely to stick together to form a lump, which may inhibit further diffusion of the excreted liquid. That is, when the basis weight of the SAP is constant in a plane, there is a possibility that so-called gel blocking may occur.

[0083] Therefore, in the absorber 20A of the present embodiment, by having the low basis weight region 212 around the high basis weight region 211, even after absorbing a certain amount of excreted liquid, the excreted liquid can be easily diffused along the low basis weight region 212, and the occurrence of the above-described gel blocking can be suppressed.

[0084] The non-laminated region 212N is arranged such that, when viewed from a certain high basis weight region 211, there are more on the width direction side than on the longitudinal direction side. In other words, among the points S with the maximum thickness, the number of points S where the non-laminated region 212N is adjacent to one side or the other side in the width direction is greater than the number of points S where the non-laminated region 212N is adjacent to one side or the other side in the longitudinal direction. As a result, the low basis weight laminated region 212E is arranged such that, when viewed from the high basis weight region 211, there are more on the longitudinal direction side than on the width direction side. In this case, when the absorber 20A is in a state of absorbing excreted liquid, that is, in a swollen state, more SAPs come into contact with each other in the longitudinal direction where many low basis weight laminated regions 212E are arranged. Therefore, it is possible to suppress the loss of flexibility in the width direction when the absorber 20A is in a swollen state.

[0085] In the absorber 20A shown in FIG. 5, a channel region 215 shown in FIG. 8 to be described later may be further provided. Although a detailed description of the channel region 215 will be given later, by the absorber 20A having the channel region 215, for example, when sandwiched between the wearer's two legs (i.e., the groin) during wearing, it becomes easier to deform in the width direction at the wearer's crotch, the storage property at the crotch increases, and the fit is further improved. At this time, since the channel region 215 itself serves as a folding starting point, it contributes to the improvement of the fit. However, the absorber 20A may not be provided with the channel region 215.

[0086] In addition, in the absorber 20A of the present embodiment, as shown in FIG. 4B, the maximum thickness T is within 3 mm, and the distance between adjacent points S having the maximum thickness is preferably 5 times or less the maximum thickness T. Thereby, while maintaining the thinness of the absorber 20A, a large number of high basis weight regions and low basis weight regions can be arranged. Therefore, in the absorber 20A having the superabsorbent polymer, the fit during wearing can be improved while maintaining the thinness. Further, it is more preferable that the maximum thickness T is within 2 mm, and the distance between adjacent points S having the maximum thickness is 4 times or less the maximum thickness T. Thereby, in the absorber 20A having the superabsorbent polymer, the fit during wearing can be improved while maintaining the thinness more effectively.

[0087] In the plan view shown in FIG. 5, the diameter of the circumscribed circle CC circumscribing each of the plurality of high basis weight regions 211 is preferably 2 mm or more and 4 mm or less. Thereby, the size of each of the plurality of high basis weight regions 211 can be reduced, and a large number of high basis weight regions 211 and low basis weight regions 212 can be arranged on the base sheet 14. Therefore, the absorber 20A can be easily deformed along the unevenness of the wearer's body, and the fit can be improved.

[0088] In addition, in the plan view shown in FIG. 5, among the diameters of the inscribed circles IC inscribed in each of the plurality of non-laminated regions 212N, the maximum diameter is preferably equal to or less than the maximum thickness T. By thus reducing the size in the plan view of the non-laminated region 212N without SAP, leakage of excreted liquid through the non-laminated region 212N can be suppressed.

[0089] Furthermore, in the plan view shown in FIG. 5, a joining portion 213 is provided outside the region where SAP is provided (that is, the high basis weight region 211 and the low basis weight region 212) in the longitudinal direction. The joining portion 213 is a portion where the base sheet 14 and another sheet 14S are joined in the thickness direction. The joining portion 213 is formed by known joining means such as embossing, welding, or adhesion. Thereby, the opening between the base sheet 14 and another sheet 14S can be suppressed.

[0090] Note that the region of the base sheet 14 where the joint portion 213 is formed is a region where no SAP is provided and is also a region where no adhesive for fixing the SAP is provided. Here, the region where no SAP is provided is a region where substantially no SAP is arranged (for example, among the weights of the SAP arranged over the entire base sheet 14, the weight of the SAP arranged in the region is 10% or less). Further, the joint portion 213 may not be provided.

[0091] FIG. 6A is a schematic cross-sectional view showing a state where a superabsorbent polymer is laminated on the base sheet 14. FIG. 6B is a schematic plan view showing the state of the recessed region 214F on one surface side of the base sheet 14.

[0092] In the present embodiment, as shown in FIG. 6A, recessed regions 214 are formed on each of one surface side and the other surface side in the thickness direction of the base sheet 14. Specifically, in the base sheet 14, a recessed region 214F is formed on one surface side, and a recessed region 214B is formed on the other surface side. On one surface in the thickness direction of the base sheet 14, a large amount of SAP is arranged in the recessed region 214F to form a high basis weight region 211. On the other hand, in a region other than the recessed region 214F, no SAP is arranged, or even if SAP is arranged, it is arranged less than in the recessed region 214F, thereby forming a low basis weight region 212 (low basis weight laminated region 212E or non-laminated region 212N).

[0093] Further, as shown in FIG. 6B, on one surface side of the base sheet 14, the recessed regions 214F are intermittently arranged in the longitudinal direction and the width direction. As a result, the point S where the high basis weight region 211 becomes the maximum thickness in the thickness direction is arranged to be intermittently located in the longitudinal direction and the width direction. Similarly, the low basis weight regions 212 (low basis weight laminated region 212E and non-laminated region 212N) are also intermittently arranged in the longitudinal direction and the width direction.

[0094] Also, the difference SB1 between the highest point H1 and the lowest point L1 in the thickness direction on one surface side of the base sheet 14 is different from the difference SB2 between the highest point H2 and the lowest point L2 in the thickness direction on the other surface side of the base sheet 14. That is, the depth of the recessed region 214 where the SAP is disposed can be made different between the recessed region 214F on one surface side of the base sheet 14 and the recessed region 214B on the other surface side. That is, in the base sheet 14 shown in FIG. 6B, the recess in the recessed region 214F on one surface side is shallow, and the recess in the recessed region 214B on the other surface side is deep.

[0095] Here, in the base sheet 14 shown in FIG. 6A, the absorber 20A is formed by disposing the SAP in the recessed region 214F on the side where the recess is shallow. However, the absorber 20A may be formed by disposing the SAP in the recessed region 214B on the side where the recess is deep. For example, more SAP can be disposed in the recessed region 214B on the side where the recess is deep than in the recessed region 214F on the side where the recess is shallow, and the absorption and retention power of the excreted liquid can be improved. Conversely, by disposing the SAP in the recessed region 214F on the side where the recess is shallow, the liquid diffusibility can be improved as compared with the recessed region 214B. Therefore, by making the depths different between the recessed region 214F and the recessed region 214B as described above, it is possible to select in which of the recessed regions 214 the SAP is disposed, and an absorber having characteristics according to the purpose can be formed.

[0096] However, the difference SB1 between the highest point H1 and the lowest point L1 in the thickness direction on the front surface side of the base sheet 14 may be the same as the difference SB2 between the highest point H2 and the lowest point L2 in the thickness direction on the back surface side of the base sheet 14. That is, the depth of the recessed region 214 where the SAP is disposed may be the same between one surface and the other surface of the base sheet 14.

[0097] As shown in FIG. 6A, on the front side of the base sheet 14, the weight of the SAP laminated below the highest point H1 is 50% or more of the weight of the SAP laminated on the entire base sheet 14. Thereby, by laminating the desired weight of the SAP in the concave region of the base sheet 14, a high basis weight region 211 can be formed at an appropriate position.

[0098] Further, in the plan view shown in FIG. 6B, among the diameters of the inscribed circles IC inscribed in each of the plurality of non-laminated regions 212N, the maximum diameter is equal to or less than the difference SB1 on the front side. Thereby, by reducing the size in plan view of the non-laminated region 212N without SAP, leakage of excreted liquid through the non-laminated region 212N can be suppressed.

[0099] Here, in the plan view shown in FIG. 6B, a region below the intermediate position M1 between the highest point H1 and the lowest point L1 shown in FIG. 6A is represented as the range of the concave region 214F. In this case, it is preferable that the total of the lengths LG1 of the plurality of concave regions 214F on the virtual line V1 passing along the longitudinal direction through the centers C of the plurality of concave regions 214F is 50% or more of the length of the entire base sheet 14. Thereby, by laminating the SAP in the desired region of the base sheet 14, a high basis weight region 211 and a low basis weight region 212 can be formed at appropriate positions.

[0100] Similarly, it is preferable that the total of the lengths LG2 of the plurality of concave regions 214F on the virtual line V2 passing along the width direction through the centers of the plurality of concave regions 214F is 50% or more of the length of the entire base sheet 14. Thereby, by laminating the SAP in the desired region of the base sheet 14, a high basis weight region 211 and a low basis weight region 212 can be formed at appropriate positions.

[0101] FIG. 7A is a schematic cross-sectional view showing the state before the absorber 20A absorbs moisture. FIG. 7B is a schematic cross-sectional view showing the state after the absorber 20A absorbs moisture.

[0102] In the absorber 20A of the present embodiment, there are a joining region 28 where the base sheet 14 and another sheet 14S are joined between the points S having the adjacent maximum thicknesses, and a non-joining region 29 where the base sheet 14 and another sheet 14S are not joined between the points S having the adjacent maximum thicknesses. Thereby, by having the joining region 28 serving as a folding starting point and the non-joining region 29 where SAP can be disposed between the base sheet 14 and another sheet 14S, it is possible to achieve both ease of deformation along the unevenness of the wearer's body and absorption and retention power of excreted liquid.

[0103] In the joining region 28, the base sheet 14 and another sheet 14S are joined via an adhesive HMA in the non-laminated region 212N. Then, when the absorber 20A absorbs moisture, as shown in FIG. 7B, the SAP swells and the joined portion of the joining region 28 between the base sheet 14 and another sheet 14S comes off. In this way, as the absorber 20A absorbs moisture and the joined portion of the joining region 28 comes off, it is possible to suppress that the swelling of the SAP is hindered by the joining region 28.

[0104] FIG. 8 is a plan schematic view of the absorber 20B of a modified example.

[0105] The absorber 20B of the modified example has a channel region 215 where the basis weight of the SAP is lower than that of the high basis weight region 211. As shown in FIG. 8, the channel region 215 extends in the longitudinal direction, and in the width direction, the width of the channel region 215 is larger than the interval between the points S having the adjacent maximum thicknesses. That is, the width of the channel region 215 is larger than the width of the low basis weight region 212 formed between the channel region 215 and the adjacent high basis weight regions 211 (that is, around the high basis weight regions 211). When the absorber 20B of the modified example is sandwiched between the wearer's legs (that is, the crotch) during wearing, for example, the channel region 215 serves as a folding starting point, becomes easily deformable in the width direction under the wearer's armpit, increases the storage property under the armpit, and further improves the fitness. Also, the excreted liquid becomes easily diffusible in the longitudinal direction.

[0106] A plurality of channel regions 215 are provided in the width direction. Specifically, as shown in FIG. 8, two channel regions 215 are provided. This further increases the storage capacity in the thigh area and can further improve the fit. However, only one channel region 215 may be provided in the width direction.

[0107] ===Absorbent Body Manufacturing Apparatus and Method for Manufacturing Absorbent Body=== Hereinafter, regarding the absorbent body 20A described above, an absorbent body manufacturing apparatus and a method for manufacturing an absorbent body will be described.

[0108] <<Configuration of Absorbent Body Manufacturing Apparatus 50>> FIG. 9 is a schematic diagram showing an overview of the absorbent body manufacturing apparatus 50.

[0109] The absorbent body manufacturing apparatus 50 is an apparatus for manufacturing an absorbent body containing a superabsorbent polymer (SAP). The absorbent body manufacturing apparatus 50 includes a conveyance unit 11x, an upstream adhesive application unit 18, a particle supply unit 19, a suction unit 11P, an adhesive discharge unit 15D, and a joint formation unit 11em.

[0110] The conveyance unit 11x is a member that conveys the base sheet 14 in the conveyance direction. In the absorbent body manufacturing apparatus 50 shown in FIG. 9, the conveyance unit 11x includes a conveyance belt 11cn and a plurality of conveyance rollers 11rn. The conveyance belt 11cn has the upper surface of an endless belt that rotates driven as the conveyance surface of the base sheet 14. That is, the conveyance belt 11cn supports the lower surface of the base sheet 14 (hereinafter, may be referred to as "one surface") and conveys the base sheet 14. Therefore, the conveyance belt 11cn may be referred to as a support part.

[0111] Also, in the absorbent body manufacturing apparatus 50 shown in FIG. 9, the conveyance unit 11x is a suction belt conveyor that conveys the base sheet 14 while sucking it by the suction unit 11P through a plurality of openings 11pn (described later) provided on the conveyance surface of the conveyance belt 11cn. The conveyance roller 11rn may be a drive roller that is driven to rotate by a drive source such as a motor, or may be a driven roller that rotates without a drive source.

[0112] The upstream adhesive application unit 18 is a member that applies an adhesive to the base sheet 14 in advance before the SAP particles 19S are supplied to the base sheet 14. As shown in FIG. 9, the upstream adhesive application unit 18 is provided upstream in the conveyance direction from the particle supply unit 19 that supplies the SAP particles 19S. The adhesive applied by the upstream adhesive application unit 18 is a hot melt adhesive here. By applying the adhesive to the base sheet 14 in advance before the SAP particles 19S are supplied to the base sheet 14 by the particle supply unit 19, the SAP particles 19S are more likely to adhere to the base sheet 14, and the amount of rebound of the SAP particles 19S can be reduced. Thereby, it is possible to suppress the SAP particles 19S from being arranged at unintended positions. However, the absorber manufacturing apparatus 50 may not have the upstream adhesive application unit 18.

[0113] The particle supply unit 19 is a member that supplies the SAP particles 19S toward the upper surface of the base sheet 14 (hereinafter, may be referred to as "the other surface"). When the particle supply unit 19 discharges the SAP particles 19S, the SAP particles 19S are supplied by gravity toward the base sheet 14 arranged on the conveyance surface of the conveyance unit 11x, or are discharged together with pressurized air.

[0114] The suction unit 11P is a member that suctions the base sheet 14 from the side of one surface (lower surface) of the base sheet 14 through a plurality of openings 11pn of the conveyance belt 11cn. Details of the suction unit 11P will be described later.

[0115] The adhesive discharge unit 15D is a member that discharges an adhesive toward the base sheet 14 together with an air flow. The adhesive discharge unit 15D is arranged downstream in the conveyance direction from the particle supply unit 19. Further, in the absorber manufacturing apparatus 50 shown in FIG. 9, the adhesive discharge unit 15D has two adhesive discharge units 15D, namely, a first adhesive discharge unit 15x1 and a second adhesive discharge unit 15x2 arranged downstream in the conveyance direction from the first adhesive discharge unit 15x1. Details of the adhesive discharge unit 15D will be described later.

[0116] The joint forming part 11em is a member that forms a joint by joining in the thickness direction after the base sheet 14 and another sheet 14S merge. The joint forming part 11em may perform, for example, embossing on the base sheet 14 and another sheet 14S, or may perform other known joining means such as welding and adhesion. The joint forming part 11em can form the joint 213 in the absorber 20A shown in FIG. 5 described above.

[0117] In this embodiment, an absorber including the above-described superabsorbent polymer is manufactured by the absorber manufacturing apparatus 50 having each of the above-described configurations. As a method for manufacturing an absorber including a superabsorbent polymer, first, a conveying step of conveying the base sheet 14 while supporting one surface (lower surface) of the base sheet 14 by a support part (conveying belt 11cn), and a particle supply step of supplying SAP particles 19S toward the other surface (upper surface) of the base sheet 14 are included at least. Thereby, an absorber having a superabsorbent polymer laminated on the base sheet 14 can be manufactured.

[0118] As a method for manufacturing an absorber including a superabsorbent polymer, in this embodiment, an adhesive may be applied toward the other surface (upper surface) of the base sheet 14 by the upstream adhesive application part 18 on the upstream side in the conveying direction of the base sheet 14 from the position where the SAP particles 19S are supplied to the base sheet 14 (upstream adhesive application step). Thereby, the SAP particles 19S can be easily attached to the base sheet 14. However, as a method for manufacturing an absorber including a superabsorbent polymer, the upstream adhesive application step may not be included.

[0119] Further, as a method for manufacturing an absorber containing a superabsorbent polymer, in the present embodiment, another sheet 14S may be supplied from the other surface (upper surface) side of the base sheet 14 so as to cover the SAP particles 19S on the downstream side in the conveyance direction of the base sheet 14 from the position where the SAP particles 19S are supplied to the base sheet 14 (separate sheet supply step). Further, in the present embodiment, in a region where the adhesive is not applied to the other surface (upper surface) of the base sheet 14, the other sheet 14S and the base sheet 14 may be joined in the thickness direction along the intersection direction intersecting the conveyance direction of the base sheet 14 (joint portion forming step). Thereby, it is possible to suppress the opening between the base sheet 14 and the other sheet 14S. However, as a method for manufacturing an absorber containing a superabsorbent polymer, it is not necessary to have a separate sheet supply step or a joint portion forming step.

[0120] In the present embodiment, the absorber is formed by being cut into a desired size further downstream of the joint portion forming step. In the present embodiment, another sheet 14S is laminated after the SAP particles are supplied onto the base sheet 14, but the present invention is not limited to this. For example, after laminating the SAP particles on the base sheet 14, the absorber can be formed only by cutting the base sheet 14 into a desired size. Alternatively, after laminating the SAP particles on the base sheet 14, a fibrous material containing pulp may be laminated to form an absorber. Thereby, it is possible to easily manufacture an absorber that can quickly temporarily absorb excreted liquid and suppress the overflow and leakage of excreted liquid during excretion. Further, when a fibrous material containing pulp is mixed as a material of the absorber in addition to the SAP particles, such a fibrous material may be supplied to the base sheet 14 before or after the particle supply unit 19 supplies the SAP particles 19S.

[0121] As described above, the conveyance unit 11x of the absorber manufacturing apparatus 50 is a suction belt conveyor that conveys the base sheet 14 while sucking it by the suction unit 11P through a plurality of openings 11pn provided on the conveyance surface of the conveyance belt 11cn. Details of the suction unit 11P and the conveyance belt 11cn will be described in this regard.

[0122] FIG. 10 is a diagram for explaining the suction opening 11su of the suction unit 11P. FIG. 11A is a schematic cross-sectional view showing a part of the conveyor belt 11cn. FIG. 11B is a schematic plan view showing a part of the conveyor belt 11cn. In FIGS. 10 and 11A, for reference, the outer contour line of the base material sheet 14 is represented by a dashed line.

[0123] As shown in FIG. 10, the suction unit 11P is provided on the side opposite to the side where the base material sheet 14 is located when viewed from the conveyor belt 11cn (support part). And in the suction unit 11P, a suction opening 11su is provided on the side where the base material sheet 14 is located. The suction unit 11P sucks from the suction opening 11su. Also, between the base material sheet 14 and the suction opening 11su of the suction unit 11P, the conveyor belt 11cn is located, and the conveyor belt 11cn conveys the base material sheet 14 in the conveying direction in the conveying direction.

[0124] The conveyor belt 11cn is, for example, a mesh belt, and a plurality of openings 11pn are provided on the conveying surface 11m of the conveyor belt 11cn. Specifically, the conveying surface 11m of the conveyor belt 11cn is formed by weaving a filament member made of a fiber such as synthetic resin like nylon as shown in FIGS. 11A and 11B. However, the filament member may be formed of a metal such as a wire. The filament member is composed of, for example, a vertical member 116 and a horizontal member 117, and the opening defined by the vertical member 116 and the horizontal member 117 becomes the opening 11pn when sucking the base material sheet 14.

[0125] In the particle supply process described above, as shown in FIG. 11A, the suction unit 11P sucks the base material sheet 14 from one side (lower surface) of the base material sheet 14 through a plurality of openings 11pn provided on the conveying surface 11m of the conveyor belt 11cn. Since the base material sheet 14 is formed of a material that is very soft and easily deformed such as a non-woven fabric as described above, the portion corresponding to the opening 11pn is pulled by the suction force generated by the suction unit 11P (refer to the white arrow in FIG. 11A), and the recessed region 214 is formed so as to correspond to the shape of the opening 11pn.

[0126] At this time, the supplied SAP particles 19S (not shown in FIG. 11A) also tend to stay in the concave region 214 of the base sheet 14 due to the suction force generated by the suction portion 11P. As a result, similarly to the description in FIG. 6A above, a large number of SAP particles 19S are arranged in the concave region 214, and the high basis weight region 211 is formed. On the other hand, in the regions other than the concave region 214 (the regions blocked by the vertical member 116 in FIG. 11A and not becoming the concave region 214), the SAP particles 19S are not arranged, or even if the SAP particles 19S are arranged, they are arranged less than in the concave region 214. As a result, the low basis weight region 212 (low basis weight laminated region 212E or non-laminated region 212N) is formed.

[0127] As described above, in the transport unit 11x of the absorber manufacturing apparatus 50, the support unit (transport belt 11cn) has a plurality of openings 11pn, and the base sheet 14 is sucked from one surface (lower surface) side of the base sheet 14 through the plurality of openings 11pn in the particle supply step, whereby an absorber in which the high basis weight region 211 and the low basis weight region 212 are formed around each high basis weight region 211 can be manufactured.

[0128] Also, as shown in FIG. 11B, the diameter of the inscribed circle IC inscribed in the opening 11pn of the transport belt 11cn is equal to or greater than the average particle diameter of the SAP particles. For example, it is preferable that the diameter of the inscribed circle IC inscribed in the opening 11pn of the transport belt 11cn is 2 mm or more and 4 mm or less. Thereby, by reducing the size of each of the plurality of high basis weight regions 211 in plan view, a large number of high basis weight regions 211 and low basis weight regions 212 can be arranged on the base sheet 14. In the present embodiment, an absorber having good SAP fit during wearing can be easily manufactured while maintaining the thickness.

[0129] In the support unit (transport belt 11cn), it is preferable that the opening ratio of the opening 11pn in the region where the opening 11pn is provided is 40% or more and 60% or less. Thereby, the high basis weight region 211 can be appropriately formed in the absorber. In the following description, the opening ratio of the opening means the ratio of the area of the opening per unit area.

[0130] FIG. 12 is a schematic plan view showing another example of the suction opening su of the suction unit 11P. In FIG. 12 as well, for reference, the outer contour line of the base sheet 14 is represented by a dashed line together with the end portion 142 in the crossing direction of the base sheet 14. Also, the position of the particle supply unit 19 in plan view is represented by a dashed-dotted line.

[0131] In the particle supply step, the suction unit 11P sucks the base sheet 14 from the side of one surface (lower surface) of the base sheet 14 through the suction opening su (the first opening region 111 and the second opening region 112 described later) shown in FIG. 12 and the opening 11pn of the above-described conveyor belt 11cn, thereby forming the absorber 20B having the channel region 215 shown in FIG. 8 above. Hereinafter, the characteristics of the suction opening su of the suction unit 11P will be described.

[0132] The suction opening su of the suction unit 11P has a first opening region 111 and a second opening region 112. As shown in FIG. 12, the second opening region 112 is adjacent to the first opening region 111 in the crossing direction that crosses the conveyance direction of the base sheet 14. Also, a plurality (here, two) of the second opening regions 112 are provided in the crossing direction. However, only one second opening region 112 may be provided.

[0133] Here, the opening ratio of the first opening region 111 is equal to or higher than the opening ratio of the opening 11pn in the region where the opening 11pn of the conveyor belt 11cn (support portion) is provided. For example, in the conveyor belt 11cn shown in FIG. 11B above, the opening 11pn is defined by the vertical member 116 and the horizontal member 117. In this case, when looking at the entire region where the opening 11pn of the conveyor belt 11cn is provided, the opening ratio of the opening 11pn is lowered by the size (width) of the vertical member 116 and the horizontal member 117. On the other hand, in the first opening region 111, the entire region is an opening (space). However, although not shown in the figure, bars may be provided at the edges of the openings in the first opening region 111. Thereby, it is possible to suppress the suction force to the extent that the shape of the base sheet 14 collapses.

[0134] Also, the aperture ratio of the second opening region 112 is lower than that of the first opening region 111 and is equal to or lower than the aperture ratio of the opening 11pn in the region where the opening 11pn of the conveyor belt 11cn (support portion) is provided. Specifically, the aperture ratio of the second opening region 112 is preferably 25% or more and 35% or less. However, the aperture ratio of the second opening region 112 may be in a range other than 25% or more and 35% or less as long as it is lower than the aperture ratio of the first opening region 111 and is equal to or lower than the aperture ratio of the opening 11pn in the region where the opening 11pn of the conveyor belt 11cn (support portion) is provided.

[0135] As described above, in the particle supply step, the particle supply unit 19 supplies the SAP particles 19S toward the other surface (upper surface) of the base material sheet 14, and the suction unit 11P sucks the base material sheet 14 from the side of one surface (lower surface) of the base material sheet 14 through the first opening region 111, the second opening region 112, and the opening 11pn of the conveyor belt 11cn. Here, as described above, the aperture ratio of the second opening region 112 is lower than that of the first opening region 111. Therefore, in plan view, the area of the base material sheet 14 sucked through the second opening region 112 has a lower suction force than the area of the base material sheet 14 sucked through the first opening region 111. At this time, the SAP particles 19S (not shown in FIG. 12) supplied to the base material sheet 14 are more likely to remain in the area of the base material sheet 14 sucked through the first opening region 111 than in the area of the base material sheet 14 sucked through the second opening region 112.

[0136] Furthermore, as described above, the aperture ratio of the second opening region 112 is equal to or less than the aperture ratio of the opening 11pn in the region where the opening 11pn of the conveyor belt 11cn is provided. Therefore, in the region of the base material sheet 14 sucked through the second opening region 112, the suction force is reduced by the second opening region 112. Then, in the region of the base material sheet 14 sucked through the second opening region 112, the suction force that would cause the portion corresponding to the opening 11pn of the base material sheet 14 to be pulled and form the recessed region 214 is suppressed. Therefore, in the region of the base material sheet 14 sucked through the second opening region 112, the formation of the high basis weight region 211 is suppressed, and the channel region 215 where the basis weight of the SAP is lower than that of the high basis weight region 211 is formed. As described above, since two second opening regions 112 are provided in the crossing direction, two channel regions 215 corresponding to each of the two second opening regions 112 are formed as in the absorber 20B shown in FIG. 8.

[0137] On the other hand, the aperture ratio of the first opening region 111 is equal to or greater than the aperture ratio of the opening 11pn in the region where the opening 11pn of the conveyor belt 11cn is provided. Therefore, in the region of the base material sheet 14 sucked through the first opening region 111, the suction force is not reduced by the first opening region 111, the recessed region 214 is formed, and it becomes easier for the base material sheet 14 to stay in the recessed region 214 due to the suction force generated by the suction portion 11P. That is, in the region sucked through the first opening region 111, the high basis weight region 211 and the low basis weight region 212 are formed.

[0138] Further, the suction opening su of the suction unit 11P has a third opening region 113 and a non-opening region 114. As shown in FIG. 12, the third opening region 113 is located downstream of the first opening region 111 in the conveyance direction and has a portion overlapping the first opening region 111 in the crossing direction. Also, the non-opening region 114 is located downstream of the second opening region 112 in the conveyance direction and has a portion overlapping the second opening region 112 in the crossing direction. The opening ratio of the third opening region 113 is lower than the opening ratio of the first opening region 111. However, the third opening region 113 may be further located upstream of the first opening region 111 in the conveyance direction, or the non-opening region 114 may be further located upstream of the second opening region 112 in the conveyance direction. Also, the suction opening su of the suction unit 11P may not have the third opening region 113 and the non-opening region 114.

[0139] In the particle supply step, a suction force continues to be generated in the third opening region 113 located downstream of the first opening region 111, and the suction force is suppressed in the non-opening region 114 located downstream of the second opening region 112. Thereby, it is possible to suppress the SAP particles that have rebounded in the region of the base sheet 14 to which the SAP particles are supplied, that is, the region of the base sheet 14 that is sucked through the first opening region 111 and the second opening region 112, from being disposed in the channel region 215 on the downstream side.

[0140] Furthermore, the suction opening su of the suction unit 11P has a fourth opening region 115. The fourth opening region 115 is provided at a position overlapping the end portion of the base sheet 14 in the crossing direction, outside the first opening region 111 and the third opening region 113 in the crossing direction in a plan view. In the conveyance step, the suction unit 11P sucks the end portion of the base sheet 14 through the fourth opening region 115 from the side of one surface (lower surface) of the base sheet 14. Thereby, it is possible to suppress the curling up of the base sheet 14 during conveyance. However, the suction opening su of the suction unit 11P may not have the fourth opening region 115.

[0141] FIG. 13 is a diagram for explaining the mode of supply of SAP particles and discharge of an adhesive in the absorber manufacturing apparatus 50.

[0142] In the absorber manufacturing apparatus 50 of the present embodiment, immediately after the step of supplying SAP particles from the particle supply unit 19 (particle supply step), the adhesive discharge unit 15D (first adhesive discharge unit 15x1) discharges the adhesive 15H together with an air stream toward the base material sheet 14 (downstream side adhesive discharge step). Here, the adhesive 15H is a hot melt adhesive and is discharged from a plurality of discharge ports (nozzles) (not shown) provided in the adhesive discharge unit 15D. After the first adhesive discharge unit 15x1 discharges the adhesive 15H, the adhesive 15H is further discharged toward the base material sheet 14 together with an air stream by the second adhesive discharge unit 15x2 installed downstream in the transport direction from the first adhesive discharge unit 15x1.

[0143] Although the adhesive 15H is discharged together with an air stream, in the present embodiment, the pressure of this air stream is the same for both the first adhesive discharge unit 15x1 and the second adhesive discharge unit 15x2. However, it is not limited to this, and they may have different air pressures.

[0144] The SAP particles 19S supplied from the particle supply unit 19 are likely to bounce back when hitting the base material sheet 14 on the transport surface 11m (see FIG. 13). In the present embodiment, it is assumed that about 60% of the SAP particles 19S supplied at one time bounce back. In addition, the supplied SAP particles 19S are likely to bounce back in an unintended direction, and there is a risk of scattering to locations where they should not be arranged.

[0145] Regarding this point, in the absorber manufacturing apparatus 50 of the present embodiment, as shown in FIG. 13, at least a part of the SAP particles 19S rebounded from the base material sheet 14 can be pushed back toward the base material sheet 14 by the adhesive 15H discharged from the adhesive discharge part 15D. "Pushing back" here means moving the SAP particles 19S in a direction opposite to the conveying direction and in the direction of gravity (vertically downward). That is, when the discharged adhesive 15H hits the SAP particles 19S rebounded from the base material sheet 14, the SAP particles 19S can be dropped again toward the base material sheet 14. Further, the air flow discharged together with the adhesive 15H can reduce the arrangement of the SAP particles 19S at unintended positions. And by the adhesive 15H entangling around the rebounded SAP particles 19S, the fixing of the SAP particles 19S to the base material sheet 14 can be performed more reliably.

[0146] Also, in the present embodiment, not only the adhesive 15H discharged from the first adhesive discharge part 15x1 but also the adhesive 15H is discharged from the second adhesive discharge part 15x2 provided downstream in the conveying direction from the first adhesive discharge part 15x1. Thereby, the rebounding of the SAP particles 19S that could not be completely pushed back by only the adhesive 15H discharged from the first adhesive discharge part 15x1 is pushed back toward the base material sheet 14 by the adhesive 15H discharged from the second adhesive discharge part 15x2, so that the rebounding amount can be further reduced. By doing so, the fixing of the SAP particles 19S to the base material sheet 14 can be performed more reliably.

[0147] Note that the absorber manufacturing apparatus 50 of the present embodiment has two adhesive discharge units 15D (first adhesive discharge unit 15x1, second adhesive discharge unit 15x2), but is not limited thereto. For example, when the amount of the supplied SAP particles 19S is small, only the first adhesive discharge unit 15x1 may be used. Further, although the first adhesive discharge unit 15x1 and the second adhesive discharge unit 15x2 can push back the rebounded SAP particles 19S, the first adhesive discharge unit 15x1 emphasizes fixing the SAP particles 19S to the base sheet 14, and the second adhesive discharge unit 15x2 can be designed mainly for the purpose of improving the adhesive strength of materials (such as the base sheet 14) and adjusting the strength.

[0148] Further, in the present embodiment, the first adhesive discharge unit 15x1 and the second adhesive discharge unit 15x2 are separated to increase the degree of freedom of each adhesive discharge unit 15D. However, the first adhesive discharge unit 15x1 and the second adhesive discharge unit 15x2 may be an integrated adhesive discharge unit. When the first adhesive discharge unit 15x1 and the second adhesive discharge unit 15x2 are installed integrally, the cost can be reduced compared to installing separate devices, and the maintenance and management of the device are also facilitated.

[0149] As described above, since the SAP particles 19S are likely to rebound when the SAP particles 19S are supplied from the particle supply unit 19, in the present embodiment, as shown in FIG. 13, the transport surface 11m of the transport belt 11cn is inclined with respect to the horizontal plane Hr such that the downstream side in the transport direction descends. By doing so, the SAP particles 19S rebounded from the base sheet 14 are likely to move downstream by gravity, and the arrangement of the SAP particles 19S at unintended positions can be reduced.

[0150] When the angle at which the conveying surface 11m shown in FIG. 13 is inclined with respect to the horizontal plane Hr is θ0, the inclination angle θ0 in the present embodiment is approximately 30 degrees. This is because the angle of repose of the SAP particles (the maximum angle of the inclined plane that maintains stability without collapsing when the particles are stacked) is between 32 degrees and 38 degrees, and the inclination angle is set in the vicinity of this angle. By setting the inclination angle θ0 to approximately 30 degrees, it is possible to prevent the SAP particles 19S discharged from the particle supply unit 19 from rolling after getting onto the base material sheet 14, and at the same time, it is possible to make it less likely to bounce back compared to the case of discharging onto a conveying surface parallel to the horizontal plane. The inclination angle θ0 when the conveying surface 11m of the conveying belt 11cn is inclined such that the downstream side goes down can be set up to approximately 75 degrees.

[0151] As described above, it is preferable that the conveying surface 11m is inclined with respect to the horizontal plane Hr such that the downstream side in the conveying direction goes down, but it is not limited thereto. For example, the conveying surface 11m may be horizontal, or may be inclined with respect to the horizontal plane Hr such that the upstream side in the conveying direction goes down. It may be inclined such that the upstream side in the conveying direction goes down (that is, the downstream side goes up). In the absorber manufacturing apparatus 50 of the present embodiment, since the conveying belt 11cn is a suction belt conveyor, if the suction force of the suction unit 11P for sucking the base material sheet 14 is increased, it is similarly possible to suppress the bouncing back of the SAP particles 19S. The inclination angle θ0 when inclined with respect to the horizontal plane Hr such that the upstream side in the conveying direction goes down can be up to approximately 45 degrees, but preferably up to approximately 30 degrees.

[0152] FIG. 14 is a diagram for explaining the suction opening 11su in the absorber manufacturing apparatus 50A of the first modification. In FIG. 14, for reference, the outer contour line of the base material sheet 14 is shown by a dashed line.

[0153] In the absorber manufacturing apparatus 50A of the first modification example, similarly to the above-described absorber manufacturing apparatus 50, a suction part 11P is provided on the side opposite to the side where the base material sheet 14 is located as viewed from the conveyor belt 11cn (support part). However, in the absorber manufacturing apparatus 50A, unlike the absorber manufacturing apparatus 50, the suction opening 11su is provided not in the suction part 11P but in another conveyor belt 11cn1. As shown in FIG. 14, a plurality of suction openings 11su are provided along the circumference of the other conveyor belt 11cn1, and the position of the suction opening 11su also moves as the other conveyor belt 11cn1 moves.

[0154] In the absorber manufacturing apparatus 50A, the other conveyor belt 11cn1 is located between the conveyor belt 11cn and the suction part 11P and moves in the same direction as the conveying direction of the conveyor belt 11cn. Thereby, wear of the conveyor belt 11cn due to rubbing against the edge of the suction opening 11su can be suppressed, and the conveyor belt 11cn can be made to have a longer life. Further, in the absorber manufacturing apparatus 50A, since the suction opening 11su is provided in the other conveyor belt 11cn1, when an adhesive adheres to the suction opening 11su, only the other conveyor belt 11cn1 can be replaced. Therefore, compared with the case where the suction opening 11su is provided on the upper surface of the suction part 11P, the replacement work when an adhesive adheres to the suction opening 11su can be easily performed.

[0155] In the absorber manufacturing apparatus 50A, the other conveyor belt 11cn1 and the conveyor belt 11cn move at the same speed, but the circumferential length of the other conveyor belt 11cn1 is different from the circumferential length of the conveyor belt 11cn. For this reason, the location where the conveyor belt 11cn rubs against the edge of the suction opening 11su also changes with each revolution. From this point as well, the conveyor belt 11cn can be made to have a longer lifespan. Also, the position where the adhesive hits the conveyor belt 11cn can be shifted with each revolution, and the clogging of the adhesive at the opening 11pn of the conveyor belt 11cn can be reduced. However, when the circumferential length of the conveyor belt 11cn is an integral multiple of the pitch PH of the plurality of suction openings su, the position where the adhesive hits the conveyor belt 11cn becomes one of the positions of the plurality of suction openings su and does not shift, so it is necessary for the circumferential length of the conveyor belt 11cn to be other than an integral multiple of the pitch PH of the plurality of suction openings su.

[0156] <<Configuration of Absorber Manufacturing Apparatus 60>> Next, based on FIGS. 15 and 16, an absorber manufacturing apparatus 60 according to another embodiment different from the above-described absorber manufacturing apparatus 50 will be described.

[0157] FIG. 15 is a schematic diagram showing an overview of the absorber manufacturing apparatus 60. FIG. 16 is a diagram for explaining the plate portion 11pt of the conveying unit 11y.

[0158] The basic configuration of the absorber manufacturing apparatus 60 is the same as that of the above-described absorber manufacturing apparatus 50. The difference in the absorber manufacturing apparatus 60 is that the conveying unit 11y that conveys the base material sheet 14 in the conveying direction has a rotating body 11tn instead of the conveyor belt 11cn. In the following description of the absorber manufacturing apparatus 60, the same components as those of the absorber manufacturing apparatus 50 are denoted by the same reference numerals, and the description of the parts common to the absorber manufacturing apparatus 50 is omitted.

[0159] As shown in FIGS. 15 and 16, in the absorber manufacturing apparatus 60, a plate portion 11pt is provided on the outer peripheral surface 11n of a rotating body 11tn that rotates in the conveyance direction. The rotating body 11tn has the conveyance surface of the base material sheet 14 on the outer peripheral side surface of the plate portion 11pt. In other words, the plate portion 11pt of the rotating body 11tn supports the surface of the base material sheet 14 on the center side of the rotating body 11tn (hereinafter sometimes referred to as "one surface") and conveys the base material sheet 14. Therefore, the plate portion 11pt of the rotating body 11tn may be referred to as a support portion.

[0160] Also, in the absorber manufacturing apparatus 60 shown in FIGS. 15 and 16, the conveyance unit 11y is a suction drum that conveys the base material sheet 14 while sucking it by a suction unit 11P through a plurality of openings 11pn provided in the conveyance surface of the plate portion 11pt of the rotating body 11tn.

[0161] In the present embodiment, an absorber containing a superabsorbent polymer is manufactured by the absorber manufacturing apparatus 60 having each of the above-described configurations. As a method for manufacturing an absorber containing a superabsorbent polymer, first, a conveyance step of conveying the base material sheet 14 while supporting one surface (the surface on the center side of the rotating body 11tn) of the base material sheet 14 by a support portion (the plate portion 11pt of the rotating body 11tn), and a particle supply step of supplying SAP particles 19S toward the other surface (the surface on the side opposite to the center side of the rotating body 11tn) of the base material sheet 14 are included at least. Thereby, an absorber having a superabsorbent polymer laminated on the base material sheet 14 can be manufactured.

[0162] The plate portion 11pt is, for example, a punching metal plate, and as shown in FIG. 16, a plurality of openings 11pn are provided in the conveyance surface of the plate portion 11pt. The suction unit 11P sucks the base material sheet 14 through the plurality of openings 11pn provided in the conveyance surface of the plate portion 11pt in the above-described particle supply step.

[0163] As described above, in the transport unit 11y of the absorber manufacturing apparatus 60, the support part (the plate part 11pt of the rotating body 11tn) has a plurality of openings 11pn. In the particle supply step, by sucking the base sheet 14 from the side of one surface (the surface on the center side of the rotating body 11tn) of the base sheet 14 through the plurality of openings 11pn, an absorber can be manufactured in which a high basis weight region 211 and low basis weight regions 212 are formed around each high basis weight region 211. Although not shown, the diameter of the inscribed circle inscribed in the opening 11pn of the plate part 11pt is equal to or larger than the average particle diameter of the SAP particles. Thereby, as described above, the SAP particles can be arranged in the concave region 214 of the base sheet 14. In the present embodiment, an absorber having SAP with good fit during wearing can be easily manufactured while maintaining the thinness.

[0164] FIG. 17 is a schematic plan view showing another example of the plate part 11pt.

[0165] The plate part 11pt shown in FIG. 17 is also a punching metal plate provided with a plurality of openings. The plate part 11pt has a first opening region 111 and a second opening region 112. As shown in FIG. 17, the second opening region 112 is adjacent to the first opening region 111 in a crossing direction that crosses the transport direction of the base sheet 14. Also, a plurality (here, two) of the second opening regions 112 are provided in the crossing direction. However, only one second opening region 112 may be provided.

[0166] In the plate part 11pt shown in FIG. 17, the opening ratio of the openings in the second opening region 112 is lower than the opening ratio of the openings in the first opening region 111. Therefore, in the region sucked through the second opening region 112, the formation of the high basis weight region 211 is suppressed, and a channel region 215 in which the basis weight of the SAP is lower than that of the high basis weight region 211 is formed. Also, in the region sucked through the first opening region 111, the high basis weight region 211 and the low basis weight regions 212 are formed.

[0167] In the particle supply step, the suction unit 11P sucks the base sheet 14 from the side of one surface of the base sheet 14 (the surface on the center side of the rotating body 11tn) through the openings (the first opening region 111 and the second opening region 112) shown in FIG. 17, whereby the absorber 20B having the channel region 215 shown in FIG. 8 described above can be formed.

[0168] FIG. 18 is a diagram for explaining the mode of supply of SAP particles and discharge of the adhesive in the absorber manufacturing apparatus 60.

[0169] Also in the absorber manufacturing apparatus 60 of the present embodiment, immediately after the step of supplying SAP particles from the particle supply unit 19 (particle supply step), the first adhesive discharge unit 15x1 (adhesive discharge unit 15D) discharges the adhesive 15H together with the air flow, and further downstream, the second adhesive discharge unit 15x2 (adhesive discharge unit 15D) discharges the adhesive 15H together with the air flow toward the base sheet 14 (adhesive discharge step).

[0170] As shown in FIG. 18, also in the absorber manufacturing apparatus 60 of the present embodiment, the adhesive 15H is discharged from the discharge ports of the respective adhesive discharge units 15D (the first adhesive discharge unit 15x1 and the second adhesive discharge unit 15x2) in a predetermined discharge direction. Specifically, in the first adhesive discharge unit 15x1, the adhesive 15H is discharged from the discharge port of the first adhesive discharge unit 15x1 in a predetermined discharge direction, and the upstream side of the discharge direction is inclined toward the downstream side of the conveyance direction so that the angle θ1 formed by the virtual line extending the discharge direction and the tangent of the rotating body 11tn at the intersection of the virtual line and the outer peripheral surface 11n of the rotating body 11tn is greater than 90 degrees. Since a part of the supplied SAP particles 19S bounces back toward the downstream in the conveyance direction, by discharging the adhesive 15H so as to cover the SAP particles 19S from the downstream side rather than discharging the adhesive 15H perpendicularly to the outer peripheral surface 11n, it becomes easier to push back the SAP particles 19S that have bounced back to the downstream side.

[0171] Also in the absorber manufacturing apparatus 60 of the present embodiment, a second adhesive discharge unit 15x2 is provided downstream of the first adhesive discharge unit 15x1 in the conveyance direction. Similar to the first adhesive discharge unit 15x1, the second adhesive discharge unit 15x2 discharges the adhesive 15H from the discharge port in a predetermined discharge direction. And the discharge direction is such that the angle θ2 formed by an imaginary line extending the discharge direction of the second adhesive discharge unit 15x2 and the tangent to the outer peripheral surface 11n of the rotating body 11tn at the intersection of the imaginary line and the outer peripheral surface 11n of the rotating body 11tn is greater than 90 degrees, and the upstream side of the discharge direction 15d2 of the second adhesive discharge unit 15x2 is inclined toward the downstream side in the conveyance direction. In the absorber manufacturing apparatus 60, by discharging the adhesive 15H at such an angle not only from the first adhesive discharge unit 15x1 but also from the second adhesive discharge unit 15x2, it becomes easier to capture the rebound of the SAP particles 19S that could not be repelled by only the adhesive 15H discharged from the first adhesive discharge unit 15x1.

[0172] Note that the angle θ2 formed by an imaginary line extending the second adhesive discharge unit 15x2 and the tangent to the outer peripheral surface 11n of the rotating body 11tn at the intersection of the imaginary line and the outer peripheral surface 11n of the rotating body 11tn is preferably larger than the angle θ1 formed by an imaginary line extending the first adhesive discharge unit 15x1 and the tangent to the outer peripheral surface 11n of the rotating body 11tn at the intersection of the imaginary line and the outer peripheral surface 11n of the rotating body 11tn (θ1 < θ2). Since the supplied SAP particles 19S tend to rebound toward the downstream in the conveyance direction, by discharging the adhesive 15H at a more inclined angle from the second adhesive discharge unit 15x2 arranged downstream of the first adhesive discharge unit 15x1, it becomes easier to capture the SAP particles 19S that have fallen to the downstream side.

[0173] FIG. 19 is a perspective view of the absorber manufacturing apparatus 60A of the second modification.

[0174] In the absorber manufacturing apparatus 60A of the second modification example, the plate portion 11pt is composed of a substrate 118 and a mesh plate 119. As shown in FIG. 19, a suction opening 11su is provided in the substrate 118. Further, an opening 11pn for sucking the base material sheet 14 is provided on the conveyance surface of the mesh plate 119. In the absorber manufacturing apparatus 60A, even when clogging of the adhesive occurs at the opening 11pn, it is only necessary to replace the mesh plate 119 which is easy to replace, so that the replacement cost can be reduced.

[0175] FIG. 20 is a schematic plan view showing another example of the substrate 118 of the plate portion 11pt.

[0176] The basic configuration of the substrate 118 shown in FIG. 20 is the same as that of the plate portion 11pt shown in FIG. 17 described above, and has a first opening region 111 and a second opening region 112. As shown in FIG. 20, the second opening region 112 is adjacent to the first opening region 111 in a crossing direction that crosses the conveyance direction of the base material sheet 14. Further, a plurality (here, two) of the second opening regions 112 are provided in the crossing direction. However, only one second opening region 112 may be provided.

[0177] In the plate portion 11pt shown in FIG. 20, the opening ratio of the openings in the second opening region 112 is lower than the opening ratio of the openings in the first opening region 111. Therefore, in the region sucked through the second opening region 112, formation of the high basis weight region 211 is suppressed, and a channel region 215 in which the basis weight of the SAP is lower than that of the high basis weight region 211 is formed. Further, in the region sucked through the first opening region 111, the high basis weight region 211 and the low basis weight region 212 are formed.

[0178] In the particle supply step, the suction unit 11P sucks the base material sheet 14 from the side of one surface (the surface on the center side of the rotating body 11tn) of the base material sheet 14 through the openings (the first opening region 111 and the second opening region 112) shown in FIG. 20, whereby the absorber 20B having the channel region 215 shown in FIG. 8 described above can be formed.

[0179] FIG. 21 is a perspective view of the absorber manufacturing apparatus 60B according to the third modification.

[0180] The absorber manufacturing apparatus 60B according to the third modification has a configuration in which a conveyor belt 11cn having a plurality of openings 11pn is wound around a rotating body provided with a suction opening 11su on its outer peripheral surface. As a method for manufacturing an absorber containing a superabsorbent polymer by the absorber manufacturing apparatus 60B, first, a conveying step of conveying the base sheet 14 while supporting one surface (the surface on the center side of the rotating body 11tn) of the base sheet 14 by a support portion (conveyor belt 11cn), and a particle supply step of supplying SAP particles 19S toward the other surface (the surface opposite to the center side of the rotating body 11tn) of the base sheet 14 are at least included. Thereby, an absorber having a superabsorbent polymer laminated on the base sheet 14 can be manufactured.

[0181] The conveyor belt 11cn is, for example, a mesh belt, and as shown in FIG. 21, a plurality of openings 11pn are provided in the conveying surface 11m of the conveyor belt 11cn. The suction portion 11P suctions the base sheet 14 through the plurality of openings 11pn provided in the conveying surface 11m of the conveyor belt 11cn in the above-described particle supply step.

[0182] As described above, in the conveying portion 11y of the absorber manufacturing apparatus 60B, the support portion (conveyor belt 11cn) has a plurality of openings 11pn, and in the particle supply step, by suctioning the base sheet 14 from the side of one surface (the surface on the center side of the rotating body 11tn) of the base sheet 14 through the plurality of openings 11pn, an absorber in which a high basis weight region 211 and low basis weight regions 212 are formed around each high basis weight region 211 can be manufactured. Also, although not shown, the diameter of the inscribed circle inscribed in the opening 11pn of the conveyor belt 11cn is equal to or greater than the average particle diameter of the SAP particles. Thereby, the SAP particles can be arranged in the concave region 214 of the base sheet 14 as described above. In the present embodiment, an absorber having a superabsorbent polymer with good fit during wearing can be easily manufactured while maintaining the thinness.

[0183] ===Others=== The above embodiments are for facilitating the understanding of the present invention and are not for limiting the interpretation of the present invention. It goes without saying that the present invention can be changed and improved without departing from its gist, and equivalents thereof are included in the present invention.

Explanation of Signs

[0184] 1 Pant-type disposable diaper (absorbent article), 2 Side joint, 10 Absorbent body, 11x, 11y Conveyor, 11cn, 11cn1 Conveyor belt, 11em Joint forming part, 11m Conveyor surface, 11n Outer peripheral surface, 11P Suction part, 11pn Opening, 11pt Plate part, 11rn Conveyor roller, 11su Suction opening, 11tn Rotating body, 12 Topsheet, 13a Backsheet (liquid-impermeable sheet), 13b Backsheet (outer cover sheet), 14 Base sheet, 14S Another sheet, 15 Leakage-preventing wall part, 15D Adhesive discharge part, 15H Adhesive, 15x1 First adhesive discharge part, 15x2 Second adhesive discharge part, 16 Leakage-preventing wall elastic member, 17 Elastic member around legs, 18 Upstream adhesive coating part, 19 Particle supply part, 19S Superabsorbent polymer (SAP) particles, 20, 20A, 20B Absorber, 21 Skin side layer (absorbent core), 22 Intermediate layer (absorbent core), 23 Non-skin side layer (absorbent core), 24, 25 Core wrap sheet, 26 Sheet, 27 SAP layer, 28 Joint region, 29 Non-joint region, 30 Front side around the body part, 31 Skin side sheet, 32 Non-skin side sheet, 33 Elastic member around the body, 34 Cover sheet, 40 Rear side around the body part, Part 40E, 41 Muscle-side sheet, 42 Non-muscle-side sheet, 43 Torso elastic member, 44 Cover sheet, Absorber manufacturing apparatuses 50, 50A, 60, 60A, 111 First opening region, 112 Second opening region, 113 Third opening region, 114 Non-opening region, 115 Fourth opening region, 116 Vertical member, 117 Horizontal member, 118 Substrate, 119 Mesh plate, 142 End, 211 High basis weight region, 212 Low basis weight region, 212E Low basis weight laminated region, 212N Non-laminated region 213 Pressing part, 214, 214F, 214B Concave region, 215 Channel region

Claims

1. A method for manufacturing an absorber containing a superabsorbent polymer, comprising: a conveying step of conveying the base sheet while supporting one surface of the base sheet by a support portion; a particle supply step of supplying superabsorbent polymer particles toward the other surface of the base sheet; and having the support portion has a plurality of openings, in a plan view, the diameter of the inscribed circle inscribed in the opening is equal to or greater than the average particle diameter of the superabsorbent polymer particles, in the particle supply step, the base sheet is sucked through the opening from the side of the one surface of the base sheet, A method for manufacturing an absorber, characterized by the above.

2. A method for manufacturing an absorber according to Claim 1, wherein in the conveying step, the support portion is a conveying belt for conveying the base sheet A method for manufacturing an absorber, characterized by the above.

3. A method for manufacturing an absorber according to Claim 2, wherein a suction portion is provided on the side opposite to the side where the base sheet is located as viewed from the support portion, another conveying belt provided with a suction opening is provided, the other conveying belt is located between the conveying belt and the suction portion and moves in the same direction as the conveying direction of the conveying belt, A method for manufacturing an absorber, characterized by the above.

4. A method for manufacturing an absorber according to Claim 2 or 3, wherein a suction portion is provided on the side opposite to the side where the base sheet is located as viewed from the support portion, the suction port of the suction portion includes a first opening region and a second opening region adjacent to the first opening region and having a lower opening ratio than the first opening region in an intersecting direction intersecting the conveying direction of the base sheet, in the particle supply step, the suction portion sucks the base sheet from the side of the one surface of the base sheet through the opening, the first opening region, and the second opening region, A method for manufacturing an absorber, characterized by the above.

5. A method for manufacturing an absorber according to Claim 4, wherein the opening ratio of the first opening region is equal to or greater than the opening ratio of the opening in the region where the opening of the support portion is provided, A method for manufacturing an absorber, characterized by the above.

6. A method for manufacturing an absorber according to Claim 4, wherein the opening ratio of the second opening region is equal to or less than the opening ratio of the opening in the region where the opening of the support portion is provided, A method for manufacturing an absorber, characterized by the above.

7. A method for manufacturing an absorber according to Claim 4, wherein A plurality of the second opening regions are provided in the crossing direction. A method for manufacturing an absorber, characterized by the above. **Claim 8** A method for manufacturing an absorber according to claim 4, wherein the suction portion includes a third opening region and a non-opening region, the third opening region is located downstream of the first opening region in the conveying direction, and has a portion overlapping with the first opening region in the crossing direction, the third opening region has a lower opening ratio than the first opening region, the non-opening region is located downstream of the second opening region in the conveying direction, and has a portion overlapping with the second opening region in the crossing direction, downstream of the position where the superabsorbent polymer particles are supplied to the base material sheet in the conveying direction of the base material sheet, the suction portion sucks the base material sheet from the side of the one surface of the base material sheet through the third opening region A method for manufacturing an absorber, characterized by the above. **Claim 9** A method for manufacturing an absorber according to claim 8, wherein the suction portion includes a fourth opening region provided outside the first opening region and the third opening region in the crossing direction in a plan view and overlapping with an end portion of the base material sheet in the crossing direction, in the conveying step, the suction portion sucks the end portion from the side of the one surface of the base material sheet through the fourth opening region A method for manufacturing an absorber, characterized by the above. **Claim 10** A method for manufacturing an absorber according to claim 1, wherein in the conveying step, the support portion is a rotating body that conveys the base material sheet A method for manufacturing an absorber, characterized by the above. **Claim 11** A method for manufacturing an absorber according to claim 10, a suction portion is provided on the side opposite to the side where the base material sheet is located as viewed from the support portion, the support portion includes a first opening and a second opening having a lower opening ratio than the first opening among the plurality of openings, in a crossing direction intersecting the conveying direction of the base material sheet, a region where the first opening is provided and a region where the second opening is provided are arranged adjacent to each other, in the particle supply step, the suction portion sucks the base material sheet from the side of the one surface of the base material sheet through the first opening and the second opening A method for manufacturing an absorber, characterized by the above. **Claim 12** A method for manufacturing an absorber according to claim 11, The region where the second opening is provided is provided in plurality in the intersecting direction. A method for manufacturing an absorber, characterized by the above.

13. A method for manufacturing an absorber according to claim 1, having an upstream-side adhesive application step of applying an adhesive toward the other surface of the base material sheet on the upstream side in the conveyance direction of the base material sheet from the position where the superabsorbent polymer particles are supplied to the base material sheet. A method for manufacturing an absorber, characterized by the above.

14. A method for manufacturing an absorber according to claim 13, on the downstream side in the conveyance direction of the base material sheet from the position where the superabsorbent polymer particles are supplied to the base material sheet, having a separate-sheet supply step of supplying a separate sheet so as to cover the superabsorbent polymer particles from the other surface side of the base material sheet, and a joint portion forming step of joining the separate sheet and the base material sheet in the thickness direction along an intersecting direction intersecting the conveyance direction of the base material sheet in a region where the adhesive is not applied on the other surface of the base material sheet. A method for manufacturing an absorber, characterized by the above.

15. A method for manufacturing an absorber according to claim 1, wherein the diameter of the inscribed circle inscribed in the opening is 2 mm or more and 4 mm or less. A method for manufacturing an absorber, characterized by the above.

16. A method for manufacturing an absorber according to claim 15, wherein in the support portion, the opening ratio of the opening in the region where the opening is provided is 40% or more and 60% or less. A method for manufacturing an absorber, characterized by the above.

17. A method for manufacturing an absorber according to claim 1, having a downstream-side adhesive discharge step of discharging an adhesive together with an air flow toward the other surface of the base material sheet on the downstream side in the conveyance direction of the base material sheet from the position where the superabsorbent polymer particles are supplied to the base material sheet, and pushing back at least a part of the superabsorbent polymer particles rebounded from the base material sheet toward the base material sheet side by the discharged adhesive. A method for manufacturing an absorber, characterized by the above.

18. A method for manufacturing an absorber according to claim 17, wherein in the conveyance step, the base material sheet is conveyed by a conveyance conveyor, and the conveyance surface of the conveyance conveyor is inclined such that the downstream side faces downward with respect to the horizontal plane. A method for manufacturing an absorber, characterized by the above.

19. A method for manufacturing the absorber according to claim 17, comprising: In the conveying step, the base sheet is conveyed by a rotating body, The adhesive is discharged in a predetermined discharge direction, and the angle formed by an imaginary line extending the discharge direction and the tangent of the rotating body at the intersection of the imaginary line and the outer peripheral surface of the rotating body is greater than 90 degrees, and the upstream side of the discharge direction is inclined toward the downstream side of the conveying direction. A method for manufacturing an absorber, characterized by the above.

20. A method for manufacturing the absorber according to claim 1, comprising: A fibrous material supply step of supplying a fibrous material containing pulp from above the superabsorbent polymer laminated on the base sheet on the downstream side in the conveying direction of the base sheet from the position where the superabsorbent polymer particles are supplied to the base sheet. A method for manufacturing an absorber, characterized by the above.

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