Absorber manufacturing method, absorber manufacturing apparatus, and absorbent article manufacturing method

Abstract

To provide an absorber manufacturing method capable of stabilizing quality of an absorber when forming a compressed groove by compressing a base material of an absorber with a side part of a recess and a side part of a projection, an absorber manufacturing apparatus, and an absorbent article manufacturing method.SOLUTION: An absorber (30) manufacturing method has a compression step (S20) which forms a compressed groove in a base material by a projection provided on one of a pair of roles facing each other and a recess provided on the other role. A compression forming part has a side compression forming part which compresses the base material, of a side part of the projection and a side part of the recess. In the compression step, the base material is delivered in a conveyance direction while compressing the base material at least with the side compression formation part. A difference in delivery speed of the base material between a delivery speed of the side compression formation part and a delivery speed of the base material of the other side in the vertical direction is 5% or less.SELECTED DRAWING: Figure 12

Description

[Technical field]

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

[0002] Patent Document 1 discloses a method for manufacturing an absorbent body compressed by a compression forming unit composed of opposing convex and concave portions. In this manufacturing method, first, an absorbent core material and the absorbent core material are covered vertically with a cover sheet to form a base material of the absorbent body. Next, compressed grooves are formed in the base material of the absorbent body by the convex portions provided on one roll and the concave portions provided on the other roll of a pair of opposing rolls. Specifically, the base material of the absorbent body is not only compressed by the tops of the convex portions and the bottoms of the concave portions, but also by the sides of the convex portions and the concave portions to form the compressed grooves. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6171118 Summary of the Invention [Problem to be solved by the invention]

[0004] In the manufacturing method of Patent Document 1, the compressed grooves are formed more strongly than in the general manufacturing method in which the base material of the absorbent body is compressed with convex parts facing parallel surfaces. As a result, the base material of the absorbent body may be damaged when the compressed grooves are formed. As a result, there is a concern that the quality of the absorbent body may not be stable.

[0005] The present invention has been made in consideration of such problems, and provides a method and apparatus for manufacturing an absorbent body, and a method for manufacturing an absorbent article, which are capable of stabilizing the quality of an absorbent body when a compressed groove is formed by compressing the base material of the absorbent body between the sides of a convex portion and a concave portion. [Means for solving the problem]

[0006] A method for manufacturing an absorbent body according to one embodiment is a method for manufacturing an absorbent body having compressed grooves formed by a compression forming section composed of opposing convex portions and concave portions. The manufacturing method includes a compression step in which the compressed grooves are formed in a base material of the absorbent body by the convex portions provided on one roll and the concave portions provided on the other roll of a pair of opposing rolls. The compression forming section includes a side compression forming section which is a section that compresses the base material among the side portions of the convex portions and the side portions of the concave portions. In the compression step, the base material is fed in a conveying direction while being compressed at least by the side compression forming section. The difference between the feed speed of the base material on one side of the side compression forming section and the feed speed of the base material on the other side in the vertical direction is within 5%.

[0007] Another embodiment of the manufacturing apparatus for absorbent bodies is an apparatus for manufacturing absorbent bodies having compressed grooves. The manufacturing apparatus has a pair of rolls facing each other, and a compression forming section that is composed of a convex portion and a concave portion facing each other and compresses the base material of the absorbent body. The compression forming section forms the compressed grooves in the base material by the convex portion provided on one roll of the pair of rolls and the concave portion provided on the other roll. The compression forming section has a side compression forming section that is a portion that compresses the base material among the side portion of the convex portion and the side portion of the concave portion. The base material is fed in the conveying direction while being compressed at least by the side compression forming section. The difference in the feed speed of the base material on one side of the side compression forming section and the other side in the vertical direction is within 5%.

[0008] A method for manufacturing an absorbent article according to another embodiment is a method for manufacturing an absorbent article comprising an absorbent body having compressed grooves compressed by a compression forming section composed of opposing convex portions and concave portions. The manufacturing method includes a compression step in which the convex portions provided on one roll and the concave portions provided on the other roll of a pair of opposing rolls form the compressed grooves in a substrate of the absorbent body. The compression forming section includes a side compression forming section which is a section that compresses the substrate between the side portions of the convex portions and the side portions of the concave portions. In the compression step, the substrate is fed in a conveying direction while being compressed at least by the side compression forming section. The difference between the feed speed of the substrate on one side of the side compression forming section and the feed speed of the substrate on the other side in the vertical direction is within 5%. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a plan view of an absorbent article according to an embodiment, as viewed from the skin facing side. [Diagram 2] FIG. 2 is a plan view of the absorbent article 1 according to the embodiment, as viewed from the non-skin facing side. [Diagram 3] FIG. 3 is a schematic cross-sectional view of the absorbent article taken along the line AA shown in FIG. [Figure 4] FIG. 4 is a schematic cross-sectional view of the absorbent article 1 in the area indicated by F4 in FIG. [Diagram 5] FIG. 5 is a plan view of the absorbent body according to the embodiment as viewed from the skin facing side T1. [Figure 6] FIG. 6 is a schematic cross-sectional view for explaining a case where the absorbent core according to the embodiment receives a force directed inward in the width direction. [Figure 7] FIG. 7 is a schematic diagram for explaining the movement of the absorbent core when a wearer wears the absorbent article according to the embodiment. [Figure 8] FIG. 8 is a plan view of an absorbent body 30 according to a modified example, as viewed from the skin facing side T1. [Figure 9] FIG. 9 is a schematic side view of a part of a manufacturing line for the absorbent article 1 according to the embodiment. [Figure 10]FIG. 10 is a schematic front view of the first compressing device 121 according to the embodiment. [Figure 11] FIG. 11 is a partially enlarged cross-sectional view of the first compression device 121 according to the embodiment. [Figure 12] FIG. 12 is a diagram for explaining the feed speed of the base material 30B. [Figure 13] FIG. 13 is a partially enlarged cross-sectional view of a first compressing device 121 according to the first modified example. [Figure 14] FIG. 14 is a partially enlarged cross-sectional view of a first compression device 121 according to the second and third modified examples. [Figure 15] FIG. 15 is a diagram for explaining a protrusion C according to the fourth modified example. [Figure 16] FIG. 16 is a schematic front view of a first compressing device 121 according to the fifth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (1) Overview of the embodiment At least the following points will become apparent from the description of this specification and the accompanying drawings. The method for manufacturing an absorbent body according to the first aspect is a method for manufacturing an absorbent body having compressed grooves formed by a compression forming section composed of a convex portion and a concave portion facing each other. The manufacturing method includes a compression step in which the convex portion provided on one roll and the concave portion provided on the other roll of a pair of facing rolls form the compressed grooves in the base material of the absorbent body. The compression forming section includes a side compression forming section which is a section that compresses the base material among the side portions of the convex portion and the side portions of the concave portion. In the compression step, the base material is fed in the conveying direction while being compressed at least by the side compression forming section. The difference between the feed speed of the base material on one side of the side compression forming section and the feed speed of the base material on the other side in the vertical direction is within 5%.

[0011] As a result of intensive research by the inventor, it was found that when the substrate of the absorbent body is compressed in the side compression forming section, a portion of the substrate is transported relatively quickly and a portion of the substrate is transported relatively slowly. For example, assume a case in which the substrate is placed on one of a pair of rolls and transported. The portion of one of the side compression forming sections (e.g., one side of the side compression forming section in the vertical direction) is closer to the rotation axis of one of the rolls than the portion of the other of the side compression forming sections (e.g., the other side of the side compression forming section in the vertical direction), so the feed speed of the substrate is relatively slow. Therefore, the portion of the substrate sent out on one side of the side compression forming section is transported relatively slowly, and the portion of the substrate sent out on the other side of the side compression forming section is transported relatively quickly. The relative speed difference causes a deviation in the transport direction within the substrate. Since the compressed portion has high rigidity, damage (especially cuts) is likely to occur due to the deviation in the transport direction. Here, by keeping the difference in the feed speed of the base material between one side and the other side of the side compression forming section within 5%, it is possible to reduce the deviation in the transport direction between the relatively fast transported part and the relatively slow transported part. As a result, damage to the base material caused by the deviation in the transport direction within the base material (particularly, breakage at the boundary between the part compressed in the side compression forming section and the part not compressed) can be suppressed, making it easier to form an absorbent body without damage.

[0012] According to a preferred embodiment, the invention according to embodiment 2 may have the following features in the invention according to embodiment 1. The shortest distance from the top of the convex portion to the bottom of the concave portion is longer than the shortest distance from the side of the convex portion to the bottom of the concave portion. The force that the base material receives from the top of the convex portion and the bottom of the concave portion is relatively weaker than the force that the base material receives from the side compression forming portion. This makes it easier for the force compressed by the side compression forming portion to escape between the top of the convex portion and the bottom of the concave portion, making it easier to suppress damage to the base material. In addition, the rigidity between the top of the convex portion and the bottom of the concave portion can be lowered compared to the portion compressed by the side compression forming portion, and deterioration of the feel of the wearer's skin in the portion between the top of the convex portion and the bottom of the concave portion can be reduced.

[0013] According to a preferred embodiment, the invention according to embodiment 3 may have the following features in the invention according to embodiment 1 or 2. The compressed forming sections are arranged at intervals in the cross direction. The compressed forming sections include a first compressed forming section and a second compressed forming section arranged adjacent to the first compressed forming section in the cross direction. The maximum difference between the feed speed of the substrate from the first compressed forming section and the feed speed of the substrate from the second compressed forming section is within 5%. This can reduce the deviation in the transport direction between the portion of the substrate that is transported relatively faster and the portion that is transported relatively slower in the first compressed forming section and the second compressed forming section. As a result, damage to the substrate caused by the deviation in the transport direction within the substrate can be suppressed.

[0014] According to a preferred embodiment, the invention according to embodiment 4 may have the following features in the invention according to embodiment 3. The lower roll of the pair of rolls having a placement surface on which the substrate is placed has the placement surface parallel to the cross direction and an end parallel surface on which the end of the substrate in the cross direction is placed. The maximum distance in the vertical direction based on the end parallel surface of each of the side compression forming parts of the plurality of compression forming parts is 5% or less of the radial distance from the rotation axis of the lower roll to the end parallel surface. The farther the side compression forming part is from the end parallel surface in the vertical direction, the greater the difference between the feed speed of the substrate at the side compression forming part and the feed speed of the substrate at the end parallel surface. By making the maximum distance of the side compression forming part 5% or less of the above-mentioned radial distance, the difference in the feed speed of the substrate at each side compression forming part can be reduced. As a result, damage to the substrate caused by deviation in the transport direction within the substrate can be suppressed.

[0015] According to a preferred embodiment, the invention according to embodiment 5 may have the following features in the invention according to embodiment 3 or 4. The spacing between the multiple compressed forming parts in the cross direction is equal to or greater than the height of the convex parts in the perpendicular direction. Since the force applied between the multiple compressed forming parts is not concentrated on a local part of the substrate but is distributed over a wide range in the cross direction, the deviation in the conveying direction per unit length in the cross direction between the multiple compressed forming parts can be reduced. The concentration of load on a local part of the substrate located between the multiple compressed forming parts can be reduced, and damage to the substrate occurring between the multiple compressed forming parts can be suppressed.

[0016] According to a preferred embodiment, the invention according to embodiment 6 may have the following features in the invention according to any one of embodiments 3 to 5. The lower roll of the pair of rolls has a mounting surface on which the base material is placed. A central region is provided which is located at the center of the mounting surface divided into five equal parts in the cross direction. In the squeezing step, any of the multiple squeezing and forming units squeezing the base material in the central region. In the squeezing step, the squeezing and forming unit squeezing the base material in the central region can hold the base material in the central region, thereby preventing the center of the base material from shifting in the cross direction. As a result, squeezing at a position different from the target due to the base material being shifted can be prevented.

[0017] According to a preferred embodiment, the invention according to embodiment 7 may have the following features in the invention according to any one of embodiments 3 to 5. The lower roll of the pair of rolls has a mounting surface on which the base material is placed. A central region located in the center when the mounting surface is divided into five equal parts in the cross direction, and side regions located on both sides of the central region in the cross direction are provided. In the squeezing step, the multiple squeezing forming parts squeezing the base material in the side regions without squeezing the base material in the central region. Since the end of the base material part located in the side region farther from the central region is a free end, the force due to squeezing is easily released on the end side. On the other hand, since the end portions on both sides of the base material part located in the central region are connected to the base material part located in the side region, the force due to squeezing is less likely to escape. By the multiple squeezing forming parts squeezing the base material in the side regions without squeezing the central region, damage to the base material can be suppressed.

[0018] According to a preferred embodiment, the invention according to embodiment 8 may have the following features in the invention according to any one of embodiments 3 to 7. The one roll has the convex portion of the first compressing and forming section and the concave portion of the second compressing and forming section. The other roll has the concave portion of the first compressing and forming section and the convex portion of the second compressing and forming section. The convex portion of the first compressing and forming section of the one roll squeezes the base material from one side in the vertical direction, and the convex portion of the second compressing and forming section of the other roll squeezes the base material from the other side in the vertical direction. This allows the base material to be pushed from both sides in the vertical direction, thereby suppressing positional deviation during transport. As a result, it is possible to suppress the base material from being squeezed at a position different from the target due to positional deviation.

[0019] According to a preferred embodiment, the invention according to embodiment 9 may have the following features in the invention according to any one of embodiments 3 to 8. In the lower roll of the pair of rolls having a placement surface on which the substrate is placed, the intermediate surface placed between the first and second compressed forming sections and facing the substrate has an inclined placement surface that is inclined with respect to the cross direction. Compared to a case in which the intermediate surface is always parallel to the cross direction, the length of the intermediate surface can be increased by the height due to the inclination. This allows the force applied between the first and second compressed forming sections to be distributed over a wide range in the cross direction without concentrating on a local portion of the substrate. This allows the deviation in the conveying direction per unit length in the cross direction between the first and second compressed forming sections to be reduced. As a result, it is possible to reduce the concentration of the load on a local portion of the substrate located between the first and second compressed forming sections, and to suppress damage to the substrate occurring between the first and second compressed forming sections.

[0020] According to a preferred embodiment, the invention according to embodiment 10 may have the following features in the invention according to any one of embodiments 3 to 9. On both sides of the cross direction of the compression forming section, a non-compression forming section is provided for transporting the substrate without compressing it. In the lower roll of the pair of rolls having a placement surface on which the substrate is placed, the non-compression forming section has a parallel extension surface extending parallel to the cross direction from the end of the compression forming section in the cross direction. The substrate portion on the parallel extension surface has a constant distance from the rotation axis of the lower roll, so that the feed speed of the substrate portion is constant. Therefore, the substrate portion does not have a deviation in the transport direction within the substrate. Therefore, the substrate portion on the parallel extension surface can absorb the deviation in the transport direction caused by the difference in the feed speed of the substrate between one side and the other side of the side compression forming section. As a result, damage to the substrate caused by the deviation in the transport direction within the substrate can be suppressed.

[0021] According to a preferred embodiment, the invention according to aspect 11 may have the following features in the invention according to aspect 10. The compressed forming portions are arranged at intervals in the cross direction. The compressed forming portions include a first compressed forming portion and a second compressed forming portion arranged adjacent to the first compressed forming portion in the cross direction. The non-compressed forming portion is provided between the first compressed forming portion and the second compressed forming portion. In the lower roll, the non-compressed forming portion is arranged between the first compressed forming portion and the second compressed forming portion and has an intermediate surface facing the substrate. In the lower roll, the intermediate surface has the parallel extension surface and an axial side parallel surface that is closer to the rotation axis of the lower roll than the parallel extension surface and extends in the cross direction. The average vertical distance from the axial side parallel surface to the upper roll of the pair of rolls is longer than the average vertical distance from the parallel extension surface to the upper roll. As a result, the distance between the upper roll and the lower roll is greater on the axial parallel surface than on the parallel extension surface, making it easier for the substrate to move vertically on the intermediate surface. This makes it easier to release the force caused by the misalignment of the transport direction between the relatively fast transported portion and the relatively slow transported portion of the first and second compressed forming sections. As a result, damage to the substrate caused by the misalignment of the transport direction within the substrate can be suppressed.

[0022] According to a preferred embodiment, the invention according to embodiment 12 may have the following features in the invention according to any one of embodiments 1 to 11. In the method for manufacturing an absorbent body, a plurality of small protrusions protruding in the vertical direction are arranged at intervals in the conveying direction on the tops of the convex portions. The small protrusions extend in the intersecting direction while inclining with respect to the conveying direction. The small protrusions overlap with the small protrusions adjacent to the small protrusions in the intersecting direction. As a result, while the small protrusions are squeezing the substrate, the adjacent small protrusions start squeezing the substrate, so that while the compressed grooves are being formed, the difference between the force applied by the small protrusions and the force applied between the plurality of small protrusions can be reduced. Damage to the substrate caused by the difference in force can be suppressed.

[0023] According to a preferred embodiment, the invention according to embodiment 13 may have the following features in the invention according to any one of embodiments 1 to 12. The method for producing an absorbent body includes, after the squeezing step, a cutting step of cutting the substrate so as to divide the substrate in the transport direction. The substrate before division is less likely to move when forming compressed grooves than the cut substrate. Therefore, it is possible to easily form compressed grooves at targeted positions, and the quality of the absorbent body can be stabilized.

[0024] According to a preferred embodiment, the invention according to embodiment 14 may have the following features in the invention according to any one of embodiments 1 to 13. The manufacturing method of the absorbent body includes a cutting step of cutting the substrate so as to divide the substrate in the conveying direction. In the compression step, the compressed grooves are formed in the cut substrate. Generally, in the cutting step, a force is applied to the substrate when the substrate is cut, causing the substrate to expand and contract. The expansion and contraction of the substrate tends to weaken the degree of compression formed in the substrate. Here, by forming compressed grooves in the cut substrate, it is possible to prevent the degree of compression from being weakened by the cutting step. The intended compression can be achieved, and the quality of the absorbent body can be stabilized.

[0025] According to a preferred embodiment, the invention according to embodiment 15 may have the following features in the invention according to any one of embodiments 1 to 14. Each of the pair of rolls has a plurality of roll sections divided in a cross direction. At least one of the compression forming sections is arranged in each of the plurality of roll sections. In the compression process, the rotation speed of each of the plurality of roll sections is controlled so that the difference in the feed speed of the substrate is within 5%. When the rotation speed of the plurality of roll sections is constant, the feed speed of the substrate changes depending on the height of the top of the convex portion of the plurality of compression forming sections, so that the height of the convex portion is limited. On the other hand, by controlling the rotation speed of each of the plurality of roll sections, the height of the convex portion is not limited, and the difference in the feed speed of the substrate can be within 1%, and damage to the substrate caused by deviation in the conveying direction can be suppressed.

[0026] According to a preferred embodiment, the invention according to embodiment 16 may have the following features in any of the inventions according to embodiment 15. There are gaps between the multiple roll sections. As a result, the substrate is not pressed down from both sides in the vertical direction in the gaps between the compression forming section arranged in a roll section and the compression forming section arranged in another roll section adjacent to the roll section, and the force applied to the substrate between these compression forming sections is easily released. This makes it possible to suppress damage to the substrate between these compression forming sections.

[0027] According to a preferred embodiment, the invention according to embodiment 17 may have the following features. The manufacturing apparatus for an absorbent body according to embodiment 17 is an apparatus for manufacturing an absorbent body having compressed grooves. The manufacturing apparatus has a pair of rolls facing each other, and a compression forming section that is composed of a convex portion and a concave portion facing each other and compresses the base material of the absorbent body. The compression forming section forms the compressed grooves in the base material by the convex portion provided on one roll of the pair of rolls and the concave portion provided on the other roll. The compression forming section has a side compression forming section that is a portion that compresses the base material among the side portion of the convex portion and the side portion of the concave portion. The base material is fed in a conveying direction while being compressed at least by the side compression forming section. The difference between the feed speed of the base material on one side of the side compression forming section and the feed speed of the base material on the other side in the vertical direction is within 5%.

[0028] According to a preferred embodiment, the invention according to embodiment 18 may have the following features. The manufacturing method for an absorbent article according to embodiment 18 is a manufacturing method for an absorbent article including an absorbent body having compressed grooves compressed by a compression forming section composed of a convex portion and a concave portion facing each other. The manufacturing method includes a compression step of forming the compressed grooves in a substrate of the absorbent body by the convex portion provided on one roll and the concave portion provided on the other roll of a pair of rolls facing each other. The compression forming section includes a side compression forming section which is a portion that compresses the substrate among the side portions of the convex portion and the side portions of the concave portion. In the compression step, the substrate is fed in a conveying direction while being compressed at least by the side compression forming section. The difference between the feed speed of the substrate on one side of the side compression forming section and the feed speed of the substrate on the other side in the vertical direction is within 5%.

[0029] (2) Overview of absorbent products The absorbent article 1 according to the embodiment will be described below with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and that the ratios of the dimensions are different from the actual ones. Therefore, the specific dimensions should be determined with reference to the following description. In addition, the drawings may include parts with different dimensional relationships and ratios. The absorbent article 1 may be an absorbent article such as a sanitary napkin, a panty liner, an incontinence pad, or a fecal pad. The absorbent article may be an article that is attached to the inside of a worn article such as underwear and used. The absorbent article 1 of the embodiment is a daytime sanitary napkin. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and that the ratios of the dimensions may be different from the actual ones. Therefore, the specific dimensions should be determined with reference to the following description. In addition, the drawings may include parts with different dimensional relationships and ratios.

[0030] FIG. 1 is a plan view of the absorbent article 1 as viewed from the skin-facing side T1. FIG. 2 is a plan view of the absorbent article 1 as viewed from the non-skin-facing side T2. FIG. 3 is a schematic cross-sectional view taken along line AA shown in FIG. 1. Here, the "skin-facing side" corresponds to the side that faces the wearer's skin during use. The "non-skin-facing side" corresponds to the side that faces away from the wearer's skin during use. The absorbent article 1 has a front-rear direction L, a width direction W, and a thickness direction T that are perpendicular to each other. In the front-rear direction L of the absorbent article 1, the side that contacts the wearer's lower abdomen is referred to as the "front side", and the side that contacts the wearer's buttocks is referred to as the "rear side".

[0031] The absorbent article 1 has a front region, a central region, and a rear region. The central region S2 is disposed between the front region S1 and the rear region S3. The central region S2 may be a region including a region facing the wearer's excretory opening, for example, the vaginal opening. When the absorbent article 1 is attached to a worn article, the central region S2 may be a region disposed under the crotch of the worn article and disposed between both legs of the wearer. When the absorbent article 1 has wings 7 described later, the central region S2 may be a region from the frontmost front edge (specifically, the front base) to the rearmost rear edge (specifically, the rear base) of the wings 7. When the absorbent article 1 does not have wings 7 and the absorbent article 1 after manufacture is folded in thirds or fourths in the front-rear direction L, the central region S2 may be a region between the first fold and the second fold from the front. In other cases, when the absorbent article 1 does not have wings 7, the central region S2 may be the central region among three equal parts of the absorbent article 1 divided in the front-to-rear direction L. The front region S1 is located forward of the central region S2. The front edge of the front region S1 defines the front edge of the absorbent article 1. The rear region S3 is located rearward of the central region S2. The rear edge of the rear region S3 defines the rear edge of the absorbent article 1.

[0032] The absorbent article 1 has at least an absorbent core 31, a top sheet 10, and a back sheet 20. The absorbent article 1 has a vertically elongated shape. The top sheet 10 is disposed on the skin-facing side T1 of the absorbent core 31 and is a sheet that contacts the wearer. The top sheet 10 may have a center sheet 11 that covers the center of the absorbent core 31 in the width direction W, and a side sheet 12 that is disposed outside the center sheet 11 in the width direction W and is disposed at least in the wing 7 described later. The side sheet 12 may have a portion disposed outside the center sheet 11 in the width direction W, and may overlap the outer portion of the center sheet 11. The side sheet 12 has a portion disposed outside the absorbent core 31 in the width direction W, and in this embodiment, is separated from the absorbent core 31 in the width direction W. The center sheet 11 is made of any sheet-like material having a structure that allows liquid to pass through, such as a nonwoven fabric, a woven fabric, a perforated plastic sheet, or a mesh sheet. The side sheet 12 may be hydrophobic. The material of the side sheet 12 may be the same as that of the center sheet 11. The center sheet 11 and the side sheet 12 may be joined by a sheet joint. The sheet joint may be constituted by a compressed portion formed by compressing the center sheet 11 and the side sheet 12, and may be configured to be visible from the skin-facing side T1 of the absorbent article 1. The sheet joint may be constituted by an assembly of dot-shaped compressed portions, and more specifically, may be constituted by an assembly of dot-shaped compressed portions arranged in a diamond shape, with the diamond shapes lined up in the front-rear direction L. The sheet joint may extend in the front-rear direction L.

[0033] The back sheet 20 is disposed on the non-skin facing side T2 of the absorbent core 31 and the fiber sheet 50, and is a sheet that contacts the worn article. The back sheet 20 is a liquid-impermeable sheet. The back sheet 20 may be made of, for example, a non-breathable resin film.

[0034] The absorbent core 31 constitutes the absorbent body 30. The absorbent core 31 may be made of an absorbent material that absorbs liquid. The absorbent material constituting the absorbent core 31 may be formed, for example, from hydrophilic fibers, pulp, and superabsorbent polymers (SAPs). The absorbent body 30 may have a core wrap sheet 32 ​​that covers the absorbent core 31. The core wrap sheet 32 ​​may be made, for example, from nonwoven fabric or tissue. As a modified example, the absorbent core 31 may not be covered by the core wrap sheet 32.

[0035] The absorbent article 1 has a wing 7. When worn, the wing 7 is folded back from the wing fold FL toward the non-skin-facing side T2 of the worn article. At least a top sheet 10 and a back sheet 20 may be disposed on the wing 7. The wing fold FL is defined by the base of the wing 7, and is a line connecting the front and rear parts of the two parts recessed inward in the width direction W. The wing 7 may be folded toward the top sheet 10 from the wing fold FL before use, and folded back to the non-skin-facing side T2 of the worn article when used. The wing 7 may be disposed with a reinforcing sheet 15 disposed between the top sheet 10 and the back sheet 20. In this specification, the term "along the front-rear direction L" means a direction having an angle of less than 45° with respect to the front-rear direction L, and the term "along the width direction W" means a direction having an angle of less than 45° with respect to the width direction W.

[0036] As shown in FIG. 2 etc., the absorbent article 1 has an adhesive part for fastening the absorbent article 1 to a wearing article such as underwear. The adhesive part is provided on the non-skin-facing side T2 of the back sheet 20, and is a region provided with fastening means for fastening the absorbent article 1 to a wearing article such as underwear. The adhesive part has a main body adhesive part 61 for fastening at least a region overlapping with the absorbent core 31 to the wearing article. The main body adhesive part 61 is provided in a region overlapping with the absorbent core 31 in the thickness direction T of the absorbent article 1. The adhesive part may have a wing adhesive part 62 for fastening the wing 7 to the wearing article. The wing adhesive part 62 is attached to the non-skin-facing side of the wing 7, and fastens to the non-skin-facing side of the wearing article when the wing 7 is folded back to the non-skin-facing side T2 of the wearing article.

[0037] (3) Details of the absorbent body and compression grooves The absorbent body 30 and the compressed grooves 40 according to the embodiment will be described in detail. FIG. 4 is a schematic cross-sectional view of the absorbent article 1 in the range indicated by F4 in FIG. 3. In FIG. 4, the top sheet 10 and the back sheet 20 are joined so as to conform to the shape of the absorbent body 30. FIG. 5 is a plan view of the absorbent body 30 as viewed from the skin-facing side T1. In FIG. 5, a first compressed groove 41, a second compressed groove 42, and a third compressed groove 43, which will be described later, are illustrated, and other compressed parts of the absorbent body 30 are omitted. FIG. 6 is a schematic cross-sectional view for explaining a case where the absorbent core 31 receives a force directed toward the inside in the width direction. FIG. 7 is a schematic view for explaining the movement of the absorbent core 31 when the wearer WA wears the absorbent article 1. Absorbent core 31A shows an example of the state of absorbent core 31 when absorbent article 1 is attached to a worn article (not shown), absorbent core 31B shows an example of the state of absorbent core 31 when absorbent article 1 attached to a worn article is pulled up slightly toward the crotch side, and absorbent core 31C shows an example of the state of absorbent core 31 when absorbent article 1 attached to a worn article is pulled up further toward the crotch side and is positioned directly below the crotch side.

[0038] As shown in Figures 4 and 6, the absorbent core 31 has a first absorbent core portion 311, a second absorbent core portion 312, and a third absorbent core portion 313. The first absorbent core portion 311 is a portion located on the non-skin facing side T2 of the first compressed groove 41 described below. The first absorbent core portion 311 is a portion overlapping the first compressed groove 41 in the thickness direction T. The first absorbent core portion 311 overlaps at least the bottom surface 41b of the first compressed groove 41 in the thickness direction T. For example, when the side portion of the first compressed groove 41 is inclined with respect to the thickness direction T, the first absorbent core portion 311 overlaps the side portion of the first compressed groove 41 in the thickness direction T.

[0039] The second absorbent core portion 312 is a portion located on the non-skin facing side T2 of the second compressed groove 42 described below. The second absorbent core portion 312 is a portion overlapping the second compressed groove 42 in the thickness direction T. The second absorbent core portion 312 overlaps at least the bottom surface 42b of the second compressed groove 42 in the thickness direction T. For example, when the side portion of the second compressed groove 42 is inclined with respect to the thickness direction T, the second absorbent core portion 312 overlaps the side portion of the second compressed groove 42 in the thickness direction T.

[0040] The third absorbent core portion 313 is a portion located on the skin side T1 of the third compressed groove 43 described below. The third absorbent core portion 313 overlaps the third compressed groove 43 in the thickness direction T. The third absorbent core portion 313 overlaps at least the bottom surface 43b of the third compressed groove 43 in the thickness direction T. For example, when the side portion of the third compressed groove 43 is inclined with respect to the thickness direction T, the third absorbent core portion 313 overlaps the side portion of the third compressed groove 43 in the thickness direction T.

[0041] The absorbent core 31 also has a non-compressed portion 35 which is a part of the absorbent core 31 and is separated from the compressed groove 40 in the width direction W. The non-compressed portion 35 is composed of a portion of the absorbent core 31 that is not compressed. When the compressed groove 40 is formed, the side portion constituting the side wall of the compressed groove 40 in the width direction W (particularly the side portion on the bottom side of the compressed groove 40) is also affected by compression and the thickness of the side portion changes, so the non-compressed portion 35 is composed of a portion that is at least 3 mm or more away from the compressed groove 40 in the width direction W.

[0042] As shown in Figs. 1 and 5, the absorbent core 31 may have at least a high basis weight region HWR disposed in a central front region described later, and a low basis weight region LWR having a basis weight lower than that of the high basis weight region HWR and disposed outside the high basis weight region HWR in the front-rear direction L. The high basis weight region HWR may be disposed in the central region S2. The high basis weight region HWR may be a region sandwiched between a pair of first compressed grooves 41 in the width direction W. The low basis weight region LWR may be disposed in the front side region S1 and the rear side region S3. The low basis weight region LWR may be a region outside the pair of first compressed grooves 41 in the width direction W. Thus, the high basis weight region HWR may be sandwiched between the low basis weight regions LWR in the width direction W.

[0043] The central region S2 may have a central front region including a region forward of the center of the central region S2 in the front-to-rear direction L. The central front region may be constituted by the first and second regions from the front when the central region S2 is divided into three in the front-to-rear direction L. The central front region may be constituted by the central region when the absorbent core 31 is divided into three in the width direction W. The central front region may be a region facing the wearer's vaginal opening. The high basis weight region HWR may be disposed in at least the central front region.

[0044] 1, 4 and 5, the absorbent article 1 has compressed grooves 40. The compressed grooves 40 are formed by compressing at least the absorbent core 31 in the thickness direction T and extend in the front-rear direction L. The compressed grooves 40 are disposed at least in the central region S2. In this embodiment, the compressed grooves 40 have a pair of first compressed grooves 41, a pair of second compressed grooves 42, and a third compressed groove 43.

[0045] The pair of first compressed grooves 41 are arranged so that at least the absorbent core 31 is compressed from the skin side T1 to the non-skin side T2 and sandwich the center of the absorbent core 31 in the width direction W. The pair of second compressed grooves 42 are arranged so that at least the absorbent core 31 is compressed from the skin side T1 to the non-skin side T2 and are arranged outside the pair of first compressed grooves 41 in the width direction of the absorbent article 1. The third compressed groove 43 is arranged so that at least the absorbent core 31 is compressed from the skin side T1 to the non-skin side T2 and is arranged between the pair of first compressed grooves 41 in the width direction W.

[0046] 4 and 6, the non-skin side 311n of the first absorbent core member 311 is located on the non-skin side T2 of the non-skin side 35n of the non-compressed portion 35, and is located on the non-skin side T2 of the non-skin side 312n of the second absorbent core member 312. Therefore, the first absorbent core member 311 is located on the non-skin side T2 of the inner absorbent core member IAC, which is the absorbent core 31 between a pair of first compressed grooves 41. The non-skin side 311n of the first absorbent core member 311 may be located on the non-skin side T2 of the non-skin side 35n of one of the non-compressed portions 35 at least in the width direction W. Similarly, the non-skin side 311n of the first absorbent core member 311 may be located on the non-skin side T2 of the non-skin side 312n of the second absorbent core member 312 on the outer side in the width direction W.

[0047] The positions of the non-skin surfaces can be compared, for example, by the following method. After a sample absorbent article 1 is immersed in liquid nitrogen and frozen, the absorbent article 1 is cut with a razor so as to obtain a cross section along the thickness direction T and width direction W, and a cross section is obtained in a plan view of the absorbent article 1. Next, the sample is returned to room temperature, and a cross-sectional image is obtained at a magnification of 50 times using an electron microscope (for example, Keyence VE7800). Then, in the cross-sectional image, the positions of the non-skin surface 311n of the first absorbent core member 311, the non-skin surface 35n of the non-compressed portion 35, and the non-skin surface 312n of the second absorbent core member 312 are visually evaluated. The non-skin surface 35n of the non-compressed portion 35 compared with the non-skin surface 311n of the first absorbent core member 311 may be, for example, the non-skin surface 35n of the portion that is located within a range of 3 mm to 10 mm from the first compression groove 41 in the width direction W and is not compressed. The non-skin surface 35n of the non-compressed portion 35 to be compared with the non-skin surface 312n of the second absorbent core portion 312 may be, for example, the non-skin surface 35n of the portion that is not compressed and is located within a range of 3 mm to 10 mm from the second compression groove 42 in the width direction W.

[0048] As shown in FIG. 6A, a case is assumed in which the absorbent core 31 receives a force F directed inward in the width direction. As shown in FIG. 6B, the first absorbent core portion 311 is located closer to the non-skin-facing side T2 than the non-skin-facing portion 35 on the outer side in the width direction, and therefore receives a force f1 having a component on the inner side in the width direction and a component in the non-skin-facing side T2 direction from the non-skin-facing portion 35. As a result, the first absorbent core portion 311 is moved inward in the width direction while being moved toward the non-skin-facing side T2 direction. Next, the first absorbent core portion 311 applies a force f2 to the non-skin-facing portion 35 on the inner side in the width direction. Specifically, the first absorbent core portion 311 is located closer to the non-skin-facing side T2 than the non-skin-facing side 35n of the non-skin-facing portion 35 on the inner side in the width direction, and therefore applies a force f2 having a component on the inner side in the width direction and a component in the skin-facing side T1 direction to the non-squeezed portion 35. Therefore, as shown in Fig. 6C, the first absorbent core portion 311 easily pushes up the unsqueezed portion 35 on the inner side in the width direction, i.e., the inner absorbent core portion IAC, from the non-skin facing side T2 to the skin facing side T1 (see absorbent core 31A and absorbent core 31B in Fig. 7). As a result, as shown in Fig. 7, the inner absorbent core portion IAC can be easily raised toward the skin facing side T1, and the center of the width direction W of the absorbent article 1 can be fitted to the excretory opening E of the wearer WA (see absorbent core 31C in Fig. 7).

[0049] Here, since the non-skin side 311n of the first absorbent core member 311 is located closer to the non-skin side T2 than the non-skin side 312n of the second absorbent core member 312, at least a part of the first absorbent core member 311 (specifically, the part of the first absorbent core member 311 located closer to the non-skin side T2 than the non-skin side 312n) is located closer to the non-skin side T2 than the second absorbent core member 312. Therefore, when the absorbent core 31 receives a force F toward the inside in the width direction, the first absorbent core member 311 is more likely to push up the absorbent core 31 on the inside in the width direction than the second absorbent core member 312. As a result, the absorbent core 31 is more likely to deform from the first compressed grooves 41 rather than the second compressed grooves 42, and the intended deformation of the absorbent core 31 can be achieved.

[0050] In addition, the second compressed grooves 42 are disposed further outboard in the width direction W than the first compressed grooves 41. Therefore, when the absorbent core 31 is subjected to a force F directed inward in the width direction, it is possible to suppress widthwise compression of the absorbent core 31 between the first compressed grooves 41 and the second compressed grooves 42. As a result, it is possible to prevent widthwise compression of the absorbent core 31 on the widthwise outer side of the first compressed grooves 41, which are the deformation base points, and it is possible to suppress lateral leakage of excrement. In this way, it is possible to achieve both a good fit in the widthwise center of the absorbent article 1 and suppression of lateral leakage of excrement.

[0051] 5, the first compressed grooves 41 may extend linearly along the front-rear direction L. At least a portion of the first compressed grooves 41 located in the central region S2 may extend linearly along the front-rear direction L. As a result, the position of the first compressed grooves 41 in the width direction W is the same at least in the central region S2, so that when the absorbent core 31 receives a force F toward the inside in the width direction in the central region S2, the force is not concentrated locally on the first compressed grooves 41, but the force is likely to be applied to the entire first compressed grooves 41. As a result, the inner absorbent core portion IAC can be easily raised toward the skin-facing side T1 over a wide range in the central region S2, and the absorbent core 31 can be deformed as intended.

[0052] Furthermore, the first compressed grooves 41 may extend continuously or intermittently from the front edge to the rear edge of the absorbent core 31. In this embodiment, the first compressed grooves 41 extend continuously from the front edge to the rear edge of the absorbent core 31. Compared to a case in which the first compressed grooves 41 do not extend from the front edge to the rear edge of the absorbent core 31, when the absorbent core 31 receives a force F directed inward in the width direction, the first absorbent core portion 311 is more likely to receive the force F directed inward in the width direction. As a result, the inner absorbent core portion IAC can be easily raised toward the skin-facing side T1, and the intended deformation of the absorbent core 31 can be achieved.

[0053] The first compressed groove 41 may extend from the high basis weight region HWR to the low basis weight region LWR. In the embodiment, the first compressed groove 41 extends from the high basis weight region HWR to the low basis weight region LWR of the front side region S1. The first compressed groove 41 also extends from the high basis weight region HWR to the low basis weight region LWR of the rear side region S3. When the absorbent core 31 is compressed to form the first compressed groove 41, the first compressed groove 41 can be provided continuously in the front-rear direction L so that the first compressed groove 41 extends from the high basis weight region HWR to the low basis weight region LWR of the rear side region S3. Since the absorbent core 31 is continuously compressed, the position of the absorbent core 31 is stable, and the first compressed groove 41 can be stably provided, thereby suppressing deterioration in quality.

[0054] In the front-rear direction L, the length of the first compressed groove 41 may be longer than the length of the wing 7. In addition, in the front-rear direction L, the length of the first compressed groove 41 may be longer than the length of the second compressed groove 42. In the front-rear direction L, the first compressed groove 41 is arranged over a wider range than the second compressed groove 42. In addition, the portion of the first compressed groove 41 where the second compressed groove 42 is not on the outer side in the width direction W is more likely to receive the force F directed inward in the width direction. Therefore, the inner absorbent core portion IAC can be easily raised toward the skin-facing side T1 over a wider range, and the intended deformation of the absorbent core 31 can be achieved.

[0055] The first compressed grooves 41 may overlap with the main body adhesive portion 61 in the thickness direction T. The main body adhesive portion 61 located on the non-skin facing side T2 of the first absorbent core portion 311 makes it difficult for the first absorbent core portion 311 to move toward the non-skin facing side T2, making it easier for the inner absorbent core portion IAC to bulge toward the skin facing side T1.

[0056] As shown in FIG. 5, when the absorbent core 31 is divided into four equal parts in the width direction W in the plan view of the absorbent article 1, a pair of outer regions OR located outside the width direction W and an inner region IR located between the pair of outer regions OR may be provided. Here, the first compressed grooves 41 may be located in the inner region IR. The inner region IR corresponds to two of the absorbent cores 31 divided into four equal parts in the width direction W. Since the first compressed grooves 41 are located in the inner region IR, the width of the inner absorbent core part IAC, which is the absorbent core 31 between the first compressed grooves 41, is less than half the width of the absorbent core 31. Therefore, compared with the case where the width of the inner absorbent core part IAC is half or more the width of the absorbent core 31, the inner absorbent core part IAC protruding toward the skin-facing side T1 can be made smaller, and the range of deformation of the absorbent core 31 starting from the first compressed groove 41 does not become large. Excessive deformation of the absorbent core 31 can be prevented, making it difficult for the wearer to feel uncomfortable. In addition, since the inner absorbent core portion IAC is small, it can easily fit between the crotch of the wearer. As a result, the inner absorbent core portion IAC can be brought closer to the wearer's excretory opening. Furthermore, a wider area can be secured on the outer side in the width direction than the first compressed groove 41, which is the deformation base point. As a result, side leakage of excrement can be suppressed.

[0057] 4, in a cross section along the width direction W and thickness direction T of the absorbent article 1, the width W1 of the first compressed groove 41 may be wider than the thickness T5 of the non-compressed portion 35. This prevents the absorbent core portion on one side of the first compressed groove 41 from coming into contact with the absorbent core portion on the other side of the first compressed groove 41 in the width direction W, making it possible to prevent the deformation of the absorbent core 31 from being hindered. As a result, the inner absorbent core portion IAC can be easily raised toward the skin-facing side T1, and the absorbent core 31 can be deformed as intended.

[0058] In the embodiment, the bottom surface 41b of the first compressed groove 41 is formed by the core wrap sheet 32. The bottom surface 41b of the first compressed groove 41 may be formed by the absorbent core 31. In the first compressed groove 41, the top sheet 10 is uncompressed. Therefore, since the top sheet 10 is not compressed, the bottom surface 41b of the first compressed groove 41 is not formed by the top sheet 10. Since the rigidity of the uncompressed parts of the top sheet 10 is lower than the rigidity of the compressed parts, even if the top sheet 10 above the first compressed groove 41 comes into contact with an excretory opening (for example, the vaginal opening), it is possible to reduce the likelihood of the wearer feeling uncomfortable.

[0059] The depth D1 of the bottom surface 41b of the first compressed grooves 41 in the high basis weight region HWR may be deeper than the depth D1 of the bottom surface 41b of the first compressed grooves 41 in the low basis weight region LWR. As a result, in the high basis weight region HWR located in the central front region, the bottom surface 41b of the first compressed grooves 41 is relatively deep, making it easier for the inner absorbent core portion IAC to rise toward the skin side, while in the low basis weight region LWR, the bottom surface 41b of the first compressed grooves 41 is relatively shallow, making it more difficult for the inner absorbent core portion IAC to rise than in the high basis weight region HWR. As a result, in regions other than the high basis weight region HWR, the inner absorbent core portion IAC is less likely to locally come into contact, making it less likely for the wearer to feel uncomfortable. The depth D1 of the bottom surface 41b of the first compression groove 41 is the distance in the thickness direction T from the opening edge of the first compression groove 41 to the bottom surface 41b (in this embodiment, the skin surface of the core wrap sheet 32 ​​on the skin surface side T1 of the absorbent core 31), as shown in Figure 4.

[0060] The first compressed grooves 41 may be disposed at the boundary between the high basis weight region HWR and the low basis weight region LWR in the width direction W. Generally, the absorbent core 31 in the high basis weight region HWR has higher rigidity than the absorbent core 31 in the low basis weight region LWR, so that a rigidity difference occurs with the first compressed grooves 41 as a boundary, making it easier to deform with the first compressed grooves 41 as a base point.

[0061] The bottom surface 41b of the first compressed groove 41 may be located on the non-skin side T2 of the non-skin side 35n of the non-compressed portion 35. As a result, the entire first absorbent core portion 311 is located on the non-skin side T2 of the inner absorbent core portion IAC of the non-compressed portion 35. Therefore, when the first absorbent core portion 311 receives a force F toward the inside in the width direction and moves toward the inside in the width direction, it becomes easier to push the inner absorbent core portion IAC further up from the non-skin side T2 to the skin side T1. As a result, it becomes easier to lift the inner absorbent core portion IAC toward the skin side T1. The bottom surface 41b of the first compressed groove 41 may be located on the non-skin side T2 of the non-skin side of the core wrap sheet 32 ​​portion that contacts the non-skin side 35n of the non-compressed portion 35 in the thickness direction T.

[0062] As shown in Fig. 5, the second compressed groove 42 may be formed by an aggregate of a plurality of dot-like compressed portions. Specifically, the second compressed groove 42 may be formed by a plurality of dot-like compressed portions arranged adjacent to each other (for example, within 3 mm). As a result, in a plan view of the absorbent article 1, a portion recessed from the skin-facing side to the non-skin-facing side may extend linearly in the front-rear direction L as the second compressed groove 42. As a modified example, the second compressed groove 42 may be formed by continuously extending compressed portions. Specifically, the second compressed groove 42 may be formed by a continuously compressed portion extending in the front-rear direction L.

[0063] In a plan view of the absorbent article 1, the second compressed groove 42 may extend in a curved shape. As a result, the widthwise distance between the position of the innermost inner edge of the second compressed groove 42 and the position of the outermost outer edge in the widthwise direction W is longer than when the second compressed groove 42 extends linearly along the front-rear direction L. Therefore, the widthwise length of the second compressed groove 42 can be secured, and the widthwise insertion of the absorbent core 31 can be suppressed by the widthwise length compared to a linear second compressed groove 42. Note that in the embodiment, the second compressed groove 42 is annular in a plan view of the absorbent article 1. Therefore, the front ends of the pair of second compressed grooves 42 are connected to each other, and the rear ends of the pair of second compressed grooves 42 are connected to each other. Each of the pair of second compressed grooves 42 is arc-shaped. As a modified example, the second compressed groove 42 may be linear.

[0064] In a plan view of the absorbent article 1, the distance in the width direction W between the first compressed grooves 41 and the second compressed grooves 42 is relatively large at the center in the front-rear direction L, and the distance in the width direction W between the first compressed grooves 41 and the second compressed grooves 42 is relatively small at the outside in the front-rear direction L. At the center in the front-rear direction L, the force toward the inside in the width direction W is strong, so the absorbent core 31 is likely to compress in the width direction, but the compression of the absorbent core 31 in the width direction can be suppressed at a position farther away from the first compressed grooves 41, which serve as the deformation base point. In the central region S2, by arranging the pair of first compressed grooves 41 on the inside of the annular second compressed groove 42, the second compressed grooves 42 are arranged on the outside in the width direction W of the pair of first compressed grooves 41.

[0065] Furthermore, at least a portion of the second compressed groove 42 that overlaps with the central front region in the width direction W may be located in each of the pair of outer regions OR. That is, the second compressed groove 42 may be located in the outer region OR outside the central front region in the width direction W. The portion of the second compressed groove 42 located in the outer region OR can suppress the occurrence of width contraction of the absorbent core 31 in the outer region OR. Since the outer region OR is located outside the width direction of the inner region IR, it is possible to make it difficult for the absorbent core 31 to contract in the width direction outside the first compressed groove 41, which is the deformation base point. A wide absorption area for excrement can be secured on the width direction outside of the central front region where excrement is likely to leak. Note that, outside the central front region in the front-rear direction L, the second compressed groove 42 may be located in the outer region OR or in the inner region IR.

[0066] As shown in Fig. 4, in this embodiment, the bottom surface 42b of the second compressed groove 42 is formed by the top sheet 10. The bottom surface 42b of the second compressed groove 42 may be formed by the absorbent core 31 or the core wrap sheet 32 ​​when the top sheet 10 is broken by compression. As shown in Fig. 4, the bottom surface 42b of the second compressed groove 42 may be located on the skin side T1 of the non-skin side 35n of the non-compressed portion 35. As a result, at least a part of the second absorbent core portion 312 is located on the skin side T1 of the non-compressed portion 35. Here, as described above, the non-skin side 311n of the first absorbent core member 311 is located closer to the non-skin side T2 than the non-skin side 32n of the second absorbent core member 312, so that when the second absorbent core member 312 receives a force F acting inward in the width direction, the absorbent core 31 between the first compressed groove 41 and the second compressed groove 42 can be easily moved in the direction from the skin side T1 to the non-skin side T2. As a result, the first absorbent core member 311 is more likely to receive a force f1 acting in the direction from the skin side T1 to the non-skin side T2, and the absorbent core 31 can more easily deform with the first compressed groove 41 as a base point than the second compressed groove 42, thereby achieving the intended deformation of the absorbent core 31.

[0067] In this embodiment, the third compressed groove 43 compresses at least the absorbent core 31 from the non-skin facing side T2 to the skin facing side T1. The third compressed groove 43 is disposed between a pair of the first compressed grooves 41 in the width direction W. This allows the third absorbent core portion 313 to move more easily toward the skin facing side T1 than the non-compressed portion 35 when subjected to a force acting inward in the width direction, and makes it easier for the inner absorbent core portion IAC to rise toward the skin facing side T1 with the third compressed groove 43 as its apex (see FIG. 7). As a result, it becomes easier to fit the inner absorbent core portion IAC to the excretion opening E.

[0068] As shown in Fig. 4, the skin surface 313s of the third absorbent core member 313 may be located on the skin surface side T1 of the skin surface 35s of the non-compressed portion 35. As a result, the portion of the third absorbent core member 313 located on the skin surface side T1 of the non-compressed portion 35 receives a force from the non-compressed portion 35 adjacent to the third absorbent core member 313 in a direction pushing the portion from the non-skin surface side T2 to the skin surface side T1, so that the third absorbent core member 313 can easily move to the skin surface side T1. As a result, the inner absorbent core member IAC can easily rise toward the skin surface side T1 with the third compressed groove 43 as the apex, and the intended deformation of the absorbent core 31 can be realized. The positional relationship between the skin surface 313s of the third absorbent core member 313 and the skin surface 35s of the non-compressed portion 35 can be visually evaluated using an electron microscope (for example, Keyence VE7800) as described above. The non-skin surface 35n of the non-compressed portion 35 is the non-skin surface 35n of the portion that is not compressed and is located within a range of at least 3 mm and no more than 10 mm from the third compression groove in the width direction W.

[0069] As shown in Fig. 4, the depth D3 of the bottom surface 43b of the third compressed groove 43 may be deeper than the depth D1 of the bottom surface 41b of the first compressed groove 41. This makes it easier for the absorbent core 31 to deform in the third compressed groove 43 than in the first compressed groove 41. As a result, the inner absorbent core portion IAC can be easily raised toward the skin-facing side T1 with the third compressed groove 43 as its apex, making it easier to fit the inner absorbent core portion IAC to the excretion opening E. Note that the depth D3 of the bottom surface 43b of the third compressed groove 43 is the distance in the thickness direction T from the opening edge of the third compressed groove 43 to the bottom surface 43b (in this embodiment, the non-skin-facing side of the core wrap sheet 32 ​​on the non-skin-facing side T2 of the absorbent core 31) as shown in Fig. 4.

[0070] The third compressed groove 43 does not need to overlap with the main body adhesive portion 61 in the thickness direction T. This allows the third absorbent core portion 313 to easily move toward the skin side T1 without being hindered by the main body adhesive portion 61. As a result, the inner absorbent core portion IAC can easily rise toward the skin side T1 with the third compressed groove 43 as its apex.

[0071] As shown in Fig. 4, in the embodiment, the absorbent core 31 and the core wrap sheet 32 ​​are compressed in the first compressed groove 41 and the third compressed groove 43. The top sheet 10 is not compressed in the first compressed groove 41 and the third compressed groove 43. Therefore, in the first compressed groove 41 and the third compressed groove 43, at least the absorbent core 31 is compressed without the top sheet 10 being compressed. When the first compressed groove 41 is formed so that the non-skin side 311n of the first absorbent core portion 311 is located closer to the non-skin side T2 than the non-skin side 35n of the non-compressed portion 35, it is necessary to compress it more strongly than in the other case. However, since the top sheet 10 is not compressed when the first compressed groove 41 is formed, there is no risk of the top sheet 10 being torn. As a result, even if the top sheet 10 comes into contact with the excretion opening E due to the inner absorbent core portion IAC being raised toward the skin-facing side T1, the top sheet 10 will not tear due to the formation of the first compressed grooves 41, making it difficult for the wearer to feel uncomfortable. Furthermore, when a user visually checks the top sheet 10, they will not think that the absorbent article 1 is defective, and deterioration in the quality of the absorbent article 1 can be suppressed.

[0072] On the other hand, in the second compressed grooves 42, the top sheet 10 is compressed in addition to the absorbent core 31 and the core wrap sheet 32. In the first compressed grooves 41 and the third compressed grooves 43, the absorbent core 31 is compressed together with the top sheet 10.

[0073] The tensile strength of the top sheet 10 in the width direction W may be 10 N / 25 mm or less. By reducing the tensile strength of the top sheet 10, the softness of the top sheet 10 can be ensured. As a result, the inner absorbent core portion IAC protrudes toward the skin-facing side T1, so that even if the top sheet 10 comes into contact with the excretion opening E, the wearer is less likely to feel uncomfortable.

[0074] The tensile strength can be measured by the following method. For example, the top sheet 10 is removed from the absorbent article 1. The top sheet 10 is cut out so that the length in the front-rear direction L of the top sheet 10 is 25 mm. The cut-out top sheet 10 is set in a tensile tester (Autograph AGS-1kNG: manufactured by Shimadzu Corporation) and the chuck distance is set to 100 mm. With one side of the cut-out top sheet 10 in the width direction W fixed, the top sheet 10 is pulled to the other side in the width direction W. The pulling speed is 100 mm / min. The maximum tensile force when the top sheet 10 breaks is measured as the tensile strength. The same measurement is performed on five samples, and the average value is taken as the tensile strength (N / 25 mm). The tensile strength of the top sheet 10 over a length of 25 mm is evaluated. Since the length of the top sheet 10 is based on 25 mm, the denominator of the unit is 25 mm.

[0075] The width of the second compressed groove 42 may be wider than the width of the first compressed groove 41. The width of the second compressed groove 42 may be wider than the width of the third compressed groove 43. This makes it possible to suppress the width of the absorbent core from being enlarged by the amount of the width of the second compressed groove 42 being wider. The width of the compressed groove 40 is the distance from one side wall to the other side wall of the compressed groove 40 in a direction perpendicular to the extension direction of the compressed groove 40 in a plan view of the absorbent article 1. The width of the first compressed groove 41 may be wider than the width of the third compressed groove 43. This makes it difficult for the absorbent cores 31 to come into contact with each other in the first compressed groove 41 compared to the third compressed groove 43. In the first compressed groove 41, the deformation of the absorbent core 31 is less likely to be hindered, and the inner absorbent core portion IAC can be easily raised toward the skin-facing side T1. Furthermore, the width of the third compressed groove 43 may be wider than the width of the first compressed groove 41. This makes it less likely that the absorbent cores 31 will come into contact with each other in the third compressed groove 43 compared to the first compressed groove 41. This makes it less likely that the deformation of the absorbent core 31 will be hindered, and makes it easier for the inner absorbent core portion to rise towards the skin-facing side with the third compressed groove 43 as its apex.

[0076] The first absorbent core portion 311 may be arranged such that relatively high rigidity portions and relatively low rigidity portions are alternately arranged in the front-rear direction L. This makes it easier for the absorbent core to bend in the front-rear direction L from the low rigidity portions as base points, making it easier for the absorbent article 1 to conform to the wearer's body in the front-rear direction L. The rigidity of the third absorbent core portion 313 may also be similar to that of the first absorbent core portion 311.

[0077] 1, the absorbent article 1 may be compressed at positions other than the compressed grooves 40. For example, in a plan view of the absorbent article 1, points may be compressed inside the annular second compressed groove 42. Also, a plurality of point-like compressed portions may be arranged in a line outside the second compressed groove 42 in the front-rear direction L. As with the second compressed groove 42, these compressed portions are formed by compressing the top sheet 10 in addition to the absorbent core 31 and the core wrap sheet 32.

[0078] (4) Absorbent body related to the modification example An absorbent body 30 according to a modified example will be described below. Differences from the above-mentioned embodiment will be mainly described. Fig. 8 is a plan view of the absorbent body 30 according to the modified example as viewed from the skin side T1. Fig. 8 shows the first compressed grooves 41 and the third compressed grooves 43, but does not show the second compressed grooves 42.

[0079] 8, in the absorbent body 30 (absorbent article 1), the first compressed grooves 41 extend intermittently in the front-rear direction L. This reduces the rigidity between the first compressed grooves 41 in the front-rear direction L (first intermittent portions 41i described below), making it easier for the absorbent core 31 to bend in the front-rear direction L between the first compressed grooves 41 in the front-rear direction L. As a result, the absorbent core 31 bends easily along the wearer's body in the front-rear direction L, making it easier for the absorbent core 31 to fit the wearer's body.

[0080] Like the first compressed grooves 41, the third compressed grooves 43 also extend intermittently in the front-to-rear direction L. Therefore, like the first compressed grooves 41, the absorbent core 31 can easily bend along the wearer's body in the front-to-rear direction L, making it easier for the absorbent core 31 to fit the wearer's body.

[0081] Each of the first compressed groove 41 and the third compressed groove 43 may extend intermittently in the front-to-rear direction L outside the central front region in the front-to-rear direction L. In a modified example, the first compressed groove 41 is not arranged in a region overlapping with the central front region in the width direction W (or thickness direction T). Meanwhile, the third compressed groove 43 is arranged in a region overlapping with the central front region in the width direction W (or thickness direction T). Also, the first compressed groove 41 may be arranged only in a position that does not overlap with the high basis weight region HWR in the thickness direction T. Meanwhile, the first compressed groove 41 may be arranged in a position that overlaps with the high basis weight region HWR in the thickness direction T. Note that, in the modified example, the region other than the high basis weight region HWR is the low basis weight region LWR.

[0082] The absorbent article 1 (absorbent body 30) may have a plurality of compressed groove portions (hereinafter referred to as first compressed groove portions 41p) constituting the first compressed groove 41, and one or more intermittent portions (hereinafter referred to as first intermittent portions 41i) between the plurality of first compressed groove portions 41p. In the front-rear direction L, the total length of the plurality of first compressed groove portions 41p may be longer than the total length of the one or more first intermittent portions 41i. This allows the absorbent core 31 to be easily bent along the wearer's body in the front-rear direction L, while ensuring the ease of deformation of the absorbent core 31 with the first compressed groove 41 as a base point, thereby realizing the intended deformation of the absorbent core 31. Note that the total length of the one or more first intermittent portions 41i does not need to include the length of the first intermittent portion 41i that is longer than the length of one first compressed groove portion 41p in the front-rear direction L. For example, the length of the first interrupted portion 41i overlapping with the high basis weight region HWR in the thickness direction T does not have to be included in the total length of the one or more first interrupted portions 41i.

[0083] Furthermore, the absorbent article 1 (absorbent body 30) may have a plurality of compressed groove portions (hereinafter referred to as third compressed groove portions 43p) constituting the third compressed groove 43, and one or more interval portions (hereinafter referred to as third interval portions 43i) between the plurality of third compressed groove portions 43p. In the front-rear direction L, the total length of the plurality of third compressed groove portions 43p may be longer than the total length of the one or more third interval portions 43i.

[0084] The position of the first intermittent portion 41i may be shifted from the position of the third intermittent portion 43i in the front-rear direction L. Therefore, the first intermittent portion 41i and the third intermittent portion 43i do not need to overlap in the width direction W, or only a portion of the first intermittent portion 41i may overlap with the third intermittent portion 43i in the width direction W.

[0085] In this modification, the first intermittent portion 41i is located forward of the third intermittent portion 43i. Here, the rigidity of the first intermittent portion 41i is lower than that of the first compressed groove 41, and the rigidity of the third intermittent portion 43i is lower than that of the third compressed groove 43. Therefore, the absorbent core 31 is more likely to bend along a line passing through the first intermittent portion 41i and the third intermittent portion 43i (i.e., a line L13 that moves toward the outside in the width direction W as it moves toward the front side in the front-rear direction L) behind the central front region. As a result, the absorbent core 31 is more likely to bend along the buttocks, which can further suppress leakage of body waste to the rear of the wearer.

[0086] In another modification, the first intermittent portion 41i may be located behind the third intermittent portion 43i. In this case, the absorbent core 31 is more likely to bend along a line passing through the first intermittent portion 41i and the third intermittent portion 43i (i.e., a line moving inward in the width direction as it moves toward the front side in the front-to-rear direction) in front of the central front region. As a result, the absorbent core 31 is more likely to bend along the abdomen, which can further suppress leakage of excrement forward of the wearer.

[0087] The length in the front-to-rear direction L of the first intermittent portion 41i may be longer than the length in the front-to-rear direction L of the second intermittent portion 42i. This makes it easier for the first compressed groove 41 to receive a force directed inward in the width direction W than the second compressed groove 42, making it easier to deform with the first compressed groove 41 as a base point. Furthermore, the length in the front-to-rear direction L of the third intermittent portion 43i may be longer than the length in the front-to-rear direction L of the second intermittent portion 42i. This makes it easier for the third compressed groove 43 to receive a force directed inward in the width direction W than the second compressed groove 42, making it easier to deform with the third compressed groove 43 as a base point.

[0088] When a plurality of first intermittent portions 41i are present, the positional relationship between the first intermittent portion 41i and the third intermittent portion 43i in the front-rear direction L is determined by the first intermittent portion 41i that is closest to the third intermittent portion 43i. Similarly, when a plurality of third intermittent portions 43i are present, the positional relationship between the first intermittent portion 41i and the third intermittent portion 43i in the front-rear direction L is determined by the third intermittent portion 43i that is closest to the first intermittent portion 41i.

[0089] (5) Absorbent body manufacturing equipment A manufacturing apparatus 100 for an absorbent body 30 according to an embodiment will be described. Fig. 9 is a schematic side view of a part of a manufacturing line for an absorbent article 1 according to an embodiment. Fig. 10 is a schematic front view of a first compression device 121 according to an embodiment. Fig. 11 is a partially enlarged cross-sectional view of the first compression device 121 according to an embodiment. Fig. 12 is a view for explaining the feed speed of a base material 30B of the absorbent body.

[0090] As shown in FIG. 9, in this embodiment, the manufacturing apparatus 100 of the absorbent body 30 has a compression device 120. The manufacturing apparatus 100 may further have a base material forming device 110 and a cutting device 130. The base material forming device 110 forms a base material of the absorbent body. For example, the base material forming device 110 may form the base material 30B of the absorbent body 30 by covering the absorbent core material 31M and the absorbent core material 31M with a covering sheet in the vertical direction TD. Alternatively, in another embodiment, the manufacturing apparatus 100 may not include a base material forming device, and may perform a compression process on a base material of the absorbent body (for example, an airlaid pulp sheet) that has been formed in advance, using a compression device 120 or the like. The base material forming device 110 has a rotating drum 111 and a supply unit 112 that supplies the absorbent core material 31M onto the outer circumferential surface of the rotating drum 111. The compression device 120 forms a compression groove 40 in the base material of the absorbent body 30. The cutting device 130 cuts the base material 30B of the absorbent body 30 so as to divide the base material 30B in the conveying direction MD. The cutting device 130 is composed of a rotating drum having a cutter blade for cutting the base material 30B. The cutter blade is attached to the outer circumferential surface of the rotating drum. The manufacturing apparatus 100 has a conveying direction MD (Machine Direction), a cross direction CD (Cross Direction) perpendicular to the conveying direction MD, and a vertical direction TD (Transverse Direction) perpendicular to the conveying direction MD and the cross direction CD.

[0091] 9, in the embodiment, the compression device 120 has a first compression device 121 and a second compression device 122. The first compression device 121 forms the first compression groove 41 and the third compression groove 43. The second compression device 122 forms the second compression groove 42.

[0092] The first compression device 121 has a pair of rolls consisting of an upper roll 121U and a lower roll 121L. As shown in FIG. 10, the upper roll 121U and the lower roll 121L face each other. The upper roll 121U rotates around a rotation axis CU parallel to the cross direction CD. The lower roll 121L rotates around a rotation axis CL parallel to the cross direction CD. The lower roll 121L has a mounting surface PS on which the substrate 30B is placed. The mounting surface PS is at least a part of the outer circumferential surface of the lower roll 121L.

[0093] The first compression device 121 has a compression forming section PF composed of a convex portion C and a concave portion R facing each other. The convex portion C has a top portion Ct and side portions Cs located on both sides of the top portion Ct in the cross direction CD. The concave portion R has a bottom portion Rb and side portions Rs located on both sides of the bottom portion Rb in the cross direction CD.

[0094] In this embodiment, the compressed forming portion PF has a side compressed forming portion PFs and a center compressed forming portion PFc. The side compressed forming portion PFs is a portion that compresses the base material 30B between the side portion Cs of the convex portion C and the side portion Rs of the concave portion R. The center compressed forming portion PFc is a portion that compresses the base material 30B between the top portion Ct of the convex portion C and the bottom portion Rb of the concave portion R.

[0095] In the embodiment, a plurality of compressed forming parts PF are arranged at intervals in the cross direction CD. As shown in FIG. 10, the plurality of compressed forming parts PF include a first compressed forming part PF1, a second compressed forming part PF2, and a third compressed forming part PF3. The second compressed forming part PF2 is arranged adjacent to the first compressed forming part PF1 on one side of the cross direction CD, and is arranged adjacent to the third compressed forming part PF3 on the other side of the cross direction CD. The first compressed forming part PF1 and the third compressed forming part PF3 are provided at positions shifted in the cross direction CD from the centers of the upper roll 121U and the lower roll 121L in the cross direction CD. The second compressed forming part PF2 is provided at the center of the upper roll 121U and the lower roll 121L in the cross direction CD. The upper roll 121U is provided with a convex part C1 of the first compressed forming part PF1, a concave part R2 of the second compressed forming part PF2, and a convex part C3 of the third compressed forming part PF3. The lower roll 121L is provided with a recess R1 of the first compressed forming portion PF1, a convex portion C2 of the second compressed forming portion PF2, and a concave portion R3 of the third compressed forming portion PF3. In the vertical direction TD, the convex portion C1 and the concave portion R1 face each other, the convex portion C2 and the concave portion R2 face each other, and the convex portion C3 and the concave portion R3 face each other.

[0096] In addition, the first compression device 121 is provided with non-compression forming sections NP on both sides of the compression forming section PF in the cross direction CD, which transport the base material 30B without compressing it. In the embodiment, the non-compression forming sections NP are provided between the first compression forming section PF1 and the second compression forming section PF2, and between the second compression forming section PF2 and the third compression forming section PF3. The non-compression forming sections NP are provided outside the first compression forming section PF1 in the cross direction CD, and outside the third compression forming section PF3 in the cross direction CD.

[0097] The configurations of the convex portion C and the concave portion R will be described with reference to Fig. 11. The convex portion C1 of the first compressed forming portion PF1 has an apex C1t and side portions C1s located on both sides of the apex C1t in the cross direction CD. The concave portion R1 of the first compressed forming portion PF1 has a bottom R1b and side portions R1s located on both sides of the bottom R1b in the cross direction CD.

[0098] The first compressed forming portion PF1 has a first side compressed forming portion PF1s and a first center compressed forming portion PF1c. The first side compressed forming portion PF1s is a portion that compresses the base material 30B between the side portion C1s of the convex portion C1 and the side portion R1s of the concave portion R1. The first side compressed forming portion PF1s has an end portion PF1sa on one side and an end portion PF1sb on the other side in the vertical direction TD. In the convex portion C1, the end portion PF1sa is an end portion on the apex C1t side, and the end portion PF1sb is an end portion on the side away from the apex C1t. In the concave portion R1, the end portion PF1sa is an end portion on the bottom R1b side, and the end portion PF1sb is an end portion on the side away from the bottom R1b. On the other hand, the first center compressed forming portion PF1c is a portion that compresses the base material 30B between the apex C1t of the convex portion C1 and the bottom R1b of the concave portion R1. In the convex portion C1, both ends of the first center compressed portion PF1c in the cross direction CD are connected to ends PF1sa of the first side compressed portion PF1s. The second compressed portion PF2 and the third compressed portion PF3 are similar to the first compressed portion PF1.

[0099] As described later, in the squeezing step, the substrate 30B is fed in the conveying direction MD while being squeezed at least in the side squeezing forming section PFs. Here, the difference in the feed speed of the substrate on one side of the side squeezing forming section PFs and the feed speed of the substrate on the other side in the vertical direction TD is within 5%. As a result of intensive studies by the inventors, it was found that when the substrate 30B is squeezed in the side squeezing forming section PFs, there are portions of the substrate 30B that are transported relatively quickly and portions that are transported relatively slowly.

[0100] For example, assume that the substrate 30B is placed on one of the pair of rolls (hereinafter, the lower roll 121L) and transported. As shown in FIG. 12, the end PF1sa on one side of the first side compression forming section PF1s is closer to the rotation axis CL of the lower roll 121L than the end PF1sb on the other side, so that the feed speed V1a of the substrate 30B at the end PF1sa is relatively slow, and the feed speed V1b of the substrate 30B at the end PF1sb is relatively fast. Specifically, the distance from the end PF1sa to the rotation axis CL is r1a, the distance from the end PF1sb to the rotation axis CL is r1b, and the difference between the end PF1sb and the end PF1sa is D1. The feed speed V is expressed as the product of the distance (radius) from the rotation axis CL to a predetermined position of the roll and the angular speed of the roll, and a relative speed difference ΔV1 occurs according to the difference D1. Therefore, the portion of the base material 30B sent out from the end PF1sa of the first side compressing and forming section PF1s is transported relatively slowly, and the portion of the base material 30B sent out from the end PF1sb of the first side compressing and forming section PF1s is transported relatively quickly. The relative speed difference ΔV1 causes a deviation in the transport direction MD within the base material 30B. Since the compressed portion has high rigidity, it is prone to breakage (especially cuts) due to the deviation in the transport direction MD.

[0101] Here, in the manufacturing method of the absorbent body 30, the difference ΔV in the feed speed of the base material 30B between one side (for example, end PF1sa) and the other side (for example, end PF1sb) of the side compression forming section PFs is set to within 5%. Specifically, the difference ΔV1 in the feed speed of the base material 30B in the first side compression forming section PF1s is set to within 5%. Also, the difference ΔV2 between the feed speed V2a of the base material 30B at the end PF2sa and the feed speed V2b of the base material 30B at the end PF2sb in the second side compression forming section PF2s is set to within 5%. This reduces the deviation in the conveying direction MD between the relatively fast conveyed portion and the relatively slow conveyed portion. As a result, damage to the base material 30B caused by the deviation in the conveying direction MD in the base material 30B (particularly, breakage at the boundary between the compressed portion and the uncompressed portion at the side compression forming section PFs) can be suppressed, making it easier to form an absorbent body 30 without damage. In order to prevent the base material 30B from twisting in the conveying direction MD, it is preferable that the difference ΔV in the feed speed of the base material 30B between one side and the other side of the side compression forming section PFs is within 4%. It is more preferable that the difference ΔV in the feed speed of the base material 30B between one side and the other side of the side compression forming section PFs is within 1.5%. For example, the difference ΔV in the feed speed of the base material 30B may be 1.01%.

[0102] 11, the shortest distance Lc from the top Ct (e.g., top C2t) of the convex portion C to the bottom Rb (e.g., bottom R2b) of the concave portion R may be longer than the shortest distance Ls from the side Cs (e.g., side C2s) of the convex portion C to the side Rs (e.g., side R2s) of the concave portion R. The force that the base material 30B receives from the top Ct and bottom Rb is relatively weaker than the force that the base material 30B receives from the side compressed portion PFs. This makes it possible to reduce the rigidity of the portion compressed by the top Ct and bottom Rb, and to reduce deterioration of the feel of the portion on the wearer's skin.

[0103] In addition, the maximum difference between the feed speed of the base material 30B of the first compression forming section PF1 and the feed speed of the base material 30B of the second compression forming section PF2 may be within 5%. Specifically, the difference between the end PF1sa of the first compression forming section PF1 and the end PF2sb of the second compression forming section PF2 may be within 5%. This reduces the deviation in the conveying direction between the relatively fast conveyed portion and the relatively slow conveyed portion of the base material 30B in the first compression forming section and the second compression forming section. As a result, damage to the base material 30B caused by the deviation in the conveying direction MD in the base material 30B can be suppressed. In addition, in order to prevent the base material 30B from twisting in the conveying direction MD, the maximum difference between the feed speed of the base material 30B of the first compression forming section PF1 and the feed speed of the base material 30B of the second compression forming section PF2 may be within 4%, preferably within 1.5%. For example, the maximum difference between these speeds may be 1.01%. The maximum difference between the feed speed of the base material 30B in the second compression forming section PF2 and the feed speed of the base material 30B in the third compression forming section PF3 may also be the same. It may be within 5%. Furthermore, the differences between the maximum feed speed and the minimum feed speed of the base material 30B in the multiple compression forming sections PF may also be the same.

[0104] 10 and 11, in the lower roll 121L, the non-compressed forming portion NP has a placement surface PS parallel to the cross direction CD and an end parallel surface EPS on which the end of the substrate 30B in the cross direction CD is placed. In the present embodiment, in the lower roll 121L, each placement surface PS of the non-compressed forming portion NP located between the multiple compressed forming portions PF is parallel to the cross direction CD.

[0105] The maximum distance Md in the vertical direction TD may be 5% or less of the radial distance r from the rotation axis CL of the lower roll 121L to the end parallel surface EPS of each of the multiple compressed forming parts PF. The maximum distance Md is preferably 2.5% or less of the radial distance r, and more preferably 1.1% or less of the radial distance r. The farther the side compressed forming part PFs is from the end parallel surface EPS in the vertical direction TD, the greater the difference between the feed speed of the substrate 30B at the side compressed forming part PFs and the feed speed of the substrate 30B at the end parallel surface EPS. By setting the maximum distance Md of the side compressed forming part PFs to 5% or less of the radial distance r, the difference in the feed speed of the substrate 30B at each side compressed forming part PFs can be reduced. As a result, damage to the substrate 30B caused by the deviation of the conveying direction MD in the substrate 30B can be suppressed. 11, for example, the end of the first side compressed forming portion PFs1 that is farthest from the reference BL in the vertical direction TD is the end PF1sa, so the maximum distance Md1 of the first side compressed forming portion PFs1 is the distance from the reference BL to the end PF1sa of the first side compressed forming portion PF1s in the recess R1. Similarly, the maximum distance Md2 of the second side compressed forming portion PFs2 is the distance from the reference BL to the end PF2sa of the second side compressed forming portion PF2s in the recess R2. Therefore, the maximum distances Md1 and Md2 may be 5% or less of the radial distance r.

[0106] In addition, the interval between the multiple compressed forming parts PF in the cross direction CD may be equal to or greater than the height of the convex part C in the vertical direction TD. This allows the force applied between the multiple compressed forming parts PF to be distributed over a wide range in the cross direction CD without concentrating on a local part of the substrate 30B, thereby reducing the deviation in the conveying direction MD per unit length in the cross direction CD between the multiple compressed forming parts PF. This reduces the concentration of the load on a local part of the substrate 30B located between the multiple compressed forming parts PF, thereby suppressing damage to the substrate 30B that occurs between the multiple compressed forming parts PF. In addition, in order to prevent the substrate 30B from twisting in the conveying direction MD, the interval between the multiple compressed forming parts PF is preferably equal to or greater than twice the height of the convex part C, and more preferably equal to or greater than five times.

[0107] As shown in FIG. 10, a central region located in the center when the placement surface PS is divided into 5 equal parts in the cross direction CD, and side regions SR located on both sides of the central region CR in the cross direction CD may be provided. Any of the multiple compression forming parts PF may be located in the central region CR. As a result, any of the multiple compression forming parts PF may compress the base material 30B in the central region CR. In the compression process described later, the compression forming part PF that compresses the base material 30B in the central region CR can press the center of the base material 30B in the cross direction CD, and the positional deviation of the center of the base material 30B can be suppressed. As a result, it is possible to suppress the base material 30B from being compressed at a position different from the target due to the positional deviation. In the embodiment, the second compression forming part PF2 is located in the central region CR, and the first compression forming part PF1 and the third compression forming part PF3 are located in the side region SR.

[0108] In the modified example, none of the multiple compression forming parts PF may squeeze the substrate 30B in the central region CR. The multiple compression forming parts PF may squeeze the substrate 30B in the side region SR of the central region CR without squeezing the substrate 30B in the central region CR. The substrate portion located in the side region SR has a free end at the end far from the central region CR, so that the force of squeezing is easily released at that end. On the other hand, the ends on both sides of the substrate portion located in the central region CR are connected to the substrate portion located in the side region, so that the force of squeezing is difficult to release. The multiple compression forming parts PF squeeze the substrate 30B in the side region SR without squeezing the central region CR, so that damage to the substrate 30B can be suppressed. The multiple compression forming parts PF may also squeeze the substrate 30B in both side regions SR without squeezing the substrate 30B in only one side region SR. Since the multiple compression forming parts PF press the base material 30B from both sides in the cross direction CD, the force is less likely to concentrate on one side in the cross direction CD. This makes it easier to balance the base material 30B when it is transported, and can prevent it from shifting in position during transport. As a result, it is possible to prevent the base material 30B from being squeezed at a position different from the target due to a shift in position.

[0109] Moreover, the upper roll 121U, which is one of the rolls, may have a convex portion C1 of the first compression forming portion PF1 and a concave portion R2 of the second compression forming portion PF2. The lower roll 121L, which is the other roll, may have a concave portion R1 of the first compression forming portion PF1 and a convex portion C2 of the second compression forming portion PF2. As a result, the convex portion C1 of the first compression forming portion PF1 squeezes the base material 30B from one side of the vertical direction TD, and the convex portion C2 of the second compression forming portion PF2 squeezes the base material 30B from the other side of the vertical direction TD. As a result, since the base material 30B is pushed from both sides in the vertical direction TD, it is possible to suppress positional deviation during transport. As a result, it is possible to suppress the base material 30B from being squeezed at a position different from the target due to positional deviation.

[0110] In the manufacturing apparatus 100 for the absorbent body 30, when the rotation speeds of the upper roll 121U and the lower roll 121L are set to the maximum value, the difference in the vertical direction TD between the feed speed of the base material 30B on one side of the side compression forming section PFs and the feed speed of the base material on the other side may be 5% or more. Depending on the type of absorbent body 30 to be manufactured, the manufacturer may control the rotation speeds of the upper roll 121U and the lower roll 121L so that the difference in the feed speeds is within 5%.

[0111] The second compression device 122 has a pair of rolls consisting of an upper roll 122U and a lower roll 122L facing each other. The upper roll 122U rotates around a rotation axis CU parallel to the cross direction CD. The lower roll 121L rotates around a rotation axis CL parallel to the cross direction CD. The second compression device 122 compresses the base material 30B with a convex portion (not shown) facing the parallel surface. The upper roll 122U is provided with a convex portion, and the lower roll 121L is provided with a parallel surface.

[0112] (6) Method of manufacturing absorbent body A manufacturing method of the absorbent body 30 will be described. In this embodiment, the manufacturing method of the absorbent body 30 has a first squeezing step S20. The manufacturing method may further have a base material forming step S10, a cutting step S30, a top sheet arranging step S40, and a second squeezing step S50. In this embodiment, the first squeezing step S20 and the second squeezing step S50 are included in the squeezing step. In other embodiments, the manufacturing method may not include a base material forming step.

[0113] In the base material forming step S10, the base material 30B of the absorbent body 30 is formed. More specifically, in the base material forming step S10, the base material 30B of the absorbent body 30 may be formed by stacking the absorbent core material 31M, which is an absorbent material that absorbs body fluids, or the absorbent material may be formed into a sheet shape to form the base material 30B of the absorbent body 30. The base material 30B of the absorbent body 30 may be formed by covering one vertical side of the absorbent core material 31M with a cover sheet, or the base material 30B of the absorbent body 30 may be formed by covering both vertical sides of the absorbent core material with a cover sheet. Preferably, in the base material forming step S10, the base material 32B1 of the cover sheet (for example, the base material 32B of the core wrap sheet 32) may be covered in the vertical direction TD. As shown in FIG. 11, the base material 32B1 of the core wrap sheet 32 ​​to be arranged on the non-skin facing side T2 is transported by a transport unit such as a belt conveyor. The absorbent core material 31M is placed on the transported base material 32B1 from the rotating drum 111. Next, the base material 32B2 of the core wrap sheet 32 ​​to be placed on the skin-facing side T1 is placed on the absorbent core material 31M. As a result, both vertical sides of the absorbent core material 31M are covered in the vertical direction TD with the base material 32B of the core wrap sheet 32, which corresponds to the covering sheet. As a result, the base material 30B of the absorbent body 30 is formed.

[0114] In the first compression step S20, the convex portion C provided on one roll of the pair of rolls and the concave portion R provided on the other roll form the compressed groove 40 in the base material 30B. In this embodiment, as shown in FIG. 11, the upper roll 121U and the lower roll 121L rotate, and the base material 30B is compressed by the convex portion C1 and the concave portion R1 in the first compression forming section PF1. Specifically, the base material 30B is compressed by the side compression forming section PFs and the center compression forming section PFc in the first compression forming section PF1. As a result, the first compressed groove 41 is formed in the base material 30B. Similarly, the base material 30B is compressed by the convex portion C3 and the concave portion R3 in the third compression forming section PF3. As a result, the first compressed groove 41 is formed in the base material 30B. Note that the second compressed groove 42 is not formed in the first compression step.

[0115] In the first squeezing step S20, the base material 30B is fed in the conveying direction MD while being squeezed at least in the side squeezing forming section PFs. In this embodiment, the base material 30B is fed in the conveying direction MD while being squeezed not only in the side squeezing forming section PFs but also in the center squeezing forming section PFc. The difference between the feed speed of the base material 30B on one side of the side squeezing forming section PFs and the feed speed of the base material 30B on the other side is within 5%.

[0116] In the cutting step S30, the substrate 30B is cut so as to divide the substrate 30B in the conveying direction MD. Specifically, the rotary drum rotates to cause a cutter blade to cut the substrate 30B. In this embodiment, the substrate 30B is cut after the first compressing step S20. The substrate 30B before division is less likely to move when forming the compressed grooves 40 than the cut substrate 30B. Therefore, it is possible to easily form the compressed grooves 40 at the desired positions, and the quality of the absorbent body 30 can be stabilized.

[0117] In the top sheet arrangement step S40, the base material 10B of the top sheet 10 is arranged on the base material 30B of the absorbent body 30. As shown in Fig. 9, in this embodiment, the base material 30B (base material 32B1) of the absorbent body 30 is covered in the vertical direction TD by the base material 10B of the top sheet 10. Therefore, the base material 10B of the top sheet 10 is arranged above the base material 30B.

[0118] In the second squeezing step S50, the base material 10B of the top sheet 10 is squeezed in addition to the base material 30B by the convex portion C provided on one roll of the pair of rolls and the concave portion R provided on the other roll to form the compressed grooves 40. In this embodiment, as shown in FIG. 11, the upper roll 122U and the lower roll 122L rotate to squeeze the base material 30B and the base material 10B. The convex portion (not shown) provided on the upper roll 122U is pressed against the flat outer peripheral surface of the lower roll 122L to form the second compressed grooves 42. Since the convex portion of the upper roll 122U and the flat outer peripheral surface of the lower roll 122L squeeze the base material 30B, the absorbent body 30 is less likely to be damaged compared to the first squeezing step S20. Therefore, the difference between the feed speed of the base material 30B at the top of the convex portion provided on the upper roll 122U and the feed speed of the base material 30B at the side of the convex portion may be 5% or more.

[0119] Thereafter, other components (e.g., the reinforcing sheet 15, the base material of the back sheet 20, etc.) are arranged on the base material 30B in which the second compressed grooves 42 are formed, and the intermediate product on which the other components are arranged is cut to manufacture the absorbent article 1. Note that other steps may be performed between the above-mentioned steps. For example, a step of forming dot-like compressed portions in the base material 32B1 may be performed between the base material forming step S10 and the first compressing step S20, or may be performed between the first compressing step S20 and the cutting step S30. A step of compressing the base material 10B of the top sheet 10 and the base material 30B of the absorbent body 30 may be performed between the top sheet arranging step S40 and the second compressing step S50, or may be performed after the second compressing step S50.

[0120] As a modified example, the first compression step S20 may be performed after the cutting step S30. Therefore, the first compression grooves 41 may be formed in the cut base material 30B, or the third compression grooves 43 may be formed. Generally, in the cutting step S30, when cutting the base material 30B, a force is applied to the base material, causing the base material to expand and contract. The degree of compression formed in the base material 30B is likely to be weakened due to the expansion and contraction of the base material 30B. Here, by forming compression grooves in the cut base material 30B, it is possible to prevent the degree of compression from being weakened by the cutting step S30. The intended compression can be achieved, and the quality of the absorbent body 30 can be stabilized.

[0121] (7) Manufacturing apparatus for absorbent bodies according to modified examples A manufacturing apparatus 100 for an absorbent body 30 according to a modified example will be described. The description will focus on parts different from the above-mentioned embodiment, and the description of similar parts will be omitted. FIG. 13 is a partially enlarged cross-sectional view of the first compression device 121 according to modified example 1. FIG. 13 is a cross-sectional view similar to FIG. 11. FIG. 14 is a partially enlarged cross-sectional view of the first compression device 121 according to modified examples 2 and 3. FIG. 14A is a partially enlarged cross-sectional view of the first compression device 121 according to modified example 2. FIG. 14B is a partially enlarged cross-sectional view of the first compression device 121 according to modified example 3. FIG. 15 is a diagram for explaining the convex portion C according to modified example 4. FIG. 15A is a diagram for explaining the convex portion C. FIG. 15B is a schematic cross-sectional view taken along the line F15B-F15B shown in FIG. 15A. FIG. 16 is a schematic front view of the first compression device 121 according to modified example 5.

[0122] 13, the compressed portion PF may have only side compressed portions PFs without having a center compressed portion PFc. Therefore, the shortest distance Lc from the top Ct of the convex portion C to the bottom Rb of the concave portion R may be longer than the thickness of the base material 30B of the absorbent body 30 (i.e., the length in the vertical direction TD). As a result, the center side of the width direction W of the compressed groove 40 is not compressed, so that the compressed force by the side compressed portion PFs can easily escape, and damage to the base material 30B can be suppressed.

[0123] As shown in FIG. 14A, in the first compression device 121, the non-compressed forming portion NP in the lower roll 121L is disposed between the first compressed forming portion PF1 and the second compressed forming portion PF2, and may have an intermediate surface IS facing the substrate 30B. The intermediate surface IS is a part of the outer peripheral surface of the lower roll 121L. The intermediate surface IS may have a parallel extension surface EXS and an axial parallel surface AS. The intermediate surface IS may be, for example, a surface from the end of the recess R1 of the first compressed forming portion PF1 (the opening edge of the recess R1) to the end of the protrusion C2 of the second compressed forming portion PF2 (the base of the protrusion C2). Note that, as shown in FIG. 14A, the surface connecting the parallel extension surface EXS and the axial parallel surface AS may be a surface extending parallel to the cross direction CD and perpendicular to the parallel extension surface EXS and the axial parallel surface AS.

[0124] The parallel extension surface EXS is a surface extending parallel to the cross direction CD from the end of the compressed forming portion PF in the cross direction CD. When the compressed forming portion PF is a recess R, the end of the compressed forming portion PF in the cross direction CD may be the opening edge of the recess (for example, the end PF1sb of the first side compressed forming portion PF1s), and when the compressed forming portion PF is a convex portion C, it may be the base of the convex portion C. For example, the parallel extension surface EXS may extend parallel from one end of the first compressed forming portion PF1 of the lower roll 121L (in FIG. 14A, the end PF1sb of the first side compressed forming portion PF1s) toward the second compressed forming portion PF2. The length Le of the parallel extension surface EXS in the cross direction CD may be longer than the depth of the recess R (i.e., the height in the vertical direction TD from the parallel extension surface EXS to the bottom Rb), and may preferably be at least twice the depth of the recess R.

[0125] The shaft-side parallel surface AS is a surface that is closer to the rotation axis CL of the lower roll 121L than the parallel extension surface EXS and extends toward the opening in the cross direction CD. As shown in Fig. 14A, when the shaft-side parallel surface AS is a surface that extends parallel to the cross direction CD from the end of the second compressed forming portion PF2 in the cross direction CD in the lower roll 121L, it may coincide with the parallel extension surface EXS extending from the second compressed forming portion PF2.

[0126] The average distance in the vertical direction TD from the shaft side parallel surface AS to the upper roll 121U may be longer than the average distance in the vertical direction TD from the parallel extension surface EXS to the upper roll 121U. Therefore, in FIG. 14A, the average value of the distance Di in the vertical direction TD from the shaft side parallel surface AS to the upper roll 121U may be larger than the average value of the distance De in the vertical direction TD from the parallel extension surface EXS to the upper roll 121U. Therefore, in the non-compression forming portion NP, a space may be provided in which the substrate 30B can move somewhat freely in the vertical direction TD. As a result, in the shaft side parallel surface AS, the distance between the upper roll 121U and the lower roll 121L is greater than that of the parallel extension surface EXS, and the substrate 30B can easily move in the vertical direction TD on the intermediate surface IS. Therefore, it becomes easier to release the force generated due to the deviation in the transport direction MD between the relatively fast transported portion and the relatively slow transported portion of the first compression forming portion PF1 and the second compression forming portion PF2. As a result, damage to the base material 30B caused by deviation in the transport direction within the base material 30B can be suppressed.

[0127] Also, as shown in FIG. 14A, the height of the bottom Rb in the vertical direction TD provided on the lower roll 121L may be 5% or less of the radial distance r from the rotation axis CL of the lower roll 121L to the end parallel surface EPS, with the end parallel surface EPS as the reference BL. The height of the bottom Rb with the end parallel surface EPS as the reference BL is preferably 2.5% or less of the radial distance r, and more preferably 1.1% or less of the radial distance r. In FIG. 14A, the heights of the bottom R1b and bottom R3b coincide with the parallel extension surface EXS and are 0% of the radial distance r. Similarly, the height of the top Ct in the vertical direction TD provided on the lower roll 121L may be 5% or less of the radial distance r, with the end parallel surface EPS as the reference BL. The height of the top Ct with the end parallel surface EPS as the reference BL is preferably 2.5% or less of the radial distance r, and more preferably 1.1% or less of the radial distance r. 14A, the height of the apex Ct coincides with the parallel extension surface EXS and is 0% of the radial distance r. With the end parallel surface EPS as the reference BL, the bottom Rb and the apex Ct provided on the lower roll 121L may be located within 5% of the radial distance r. This prevents the substrate 30B from being significantly displaced in the vertical direction TD from one side of the substrate 30B in the cross direction CD to the other side when forming the compressed grooves 40 in the first compressing step S20, thereby preventing damage to the substrate 30B.

[0128] 14A, the recesses R of the lower roll 121L may be farther away from the rotation axis CL in the vertical direction TD than the protrusions C. Therefore, the recesses R may be disposed at a higher position than the protrusions in the vertical direction TD. In such a case, parallel extending surfaces EXS may extend from both ends of the recesses R in the cross direction CD.

[0129] Also, as shown in FIG. 14B, in the lower roll 121L, the intermediate surface IS may have an inclined placement surface INS inclined with respect to the cross direction CD. Compared to the case where the intermediate surface IS is always parallel to the cross direction CD, the length of the intermediate surface IS can be increased by the height due to the inclination. For example, in the embodiment of FIG. 11 and the modified example of FIG. 14B, the length of the cross direction CD between the first compressed forming portion PF1 and the second compressed forming portion PF2 is the same. In FIG. 11, the length of the intermediate surface (parallel extension surface EXS) that is always parallel to the cross direction CD and disposed between the first compressed forming portion PF1 and the second compressed forming portion PF2 is equal to the length in the cross direction CD between the first compressed forming portion PF1 and the second compressed forming portion PF2. On the other hand, in FIG. 14B, the length of the intermediate surface IS is the sum of the length (Le) of the parallel extending surface EXS on the first compressing and forming section PF1 side in the cross direction CD, the length of the inclined placement surface INS, and the length of the parallel extending surface EXS on the second compressing and forming section PF2 side in the cross direction CD. Here, if the length of the inclined placement surface INS in the cross direction CD is a and the length of the inclined placement surface INS in the vertical direction TD is b, the length of the inclined placement surface INS is (a 2 +b 2 ) 1 / 2 and is larger than the length a in the cross direction CD of the inclined placement surface INS. Therefore, the length of the intermediate surface IS in FIG. 14B is longer than the length of the intermediate surface (parallel extension surface EXS) in FIG. 11 by the height due to the inclination. As a result, the force applied between the first compressed forming portion PF1 and the second compressed forming portion PF2 is not concentrated on a local portion of the substrate 30B, but is distributed over a wide range in the cross direction. As a result, the deviation in the conveying direction MD per unit length in the cross direction CD between the first compressed forming portion PF1 and the second compressed forming portion PF2 can be reduced. As a result, the concentration of the load on a local portion of the substrate located between the first compressed forming portion PF1 and the second compressed forming portion PF2 can be reduced, and damage to the substrate occurring between the first compressed forming portion PF1 and the second compressed forming portion PF2 can be suppressed. Furthermore, when the substrate 30B is conveyed while being supported by the inclined placement surface INS, the positional deviation of the substrate 30B during conveyance can be suppressed. The angle of the inclined placement surface INS with respect to the cross direction CD is preferably from 10 degrees to 30 degrees.

[0130] Also, as shown in FIG. 15, the top Ct of the convex portion C may have a plurality of small protrusions SC protruding in the vertical direction TD and arranged at intervals in the conveying direction MD. The small protrusions SC may extend in the cross direction CD while being inclined with respect to the conveying direction MD. The small protrusions SC may overlap with the small protrusions SC adjacent to the small protrusions SC in the cross direction CD. Specifically, as shown in FIG. 15A, the small protrusions SC may have a first small protrusion SC1 and a second small protrusion SC2. The second small protrusions SC2 are adjacent to each other in the conveying direction MD. Here, in the conveying direction MD, the rear end edge SC1b of the first small protrusion SC1 may be located rearward of the front end edge SC1a of the second small protrusion SC2. As a result, while the small protrusions SC are squeezing the substrate 30B, the adjacent small protrusions SC start squeezing the substrate 30B, so that while the compressed grooves 40 are being formed, the difference between the force applied by the small protrusions SC and the force applied between the small protrusions SC and the small protrusions SC can be reduced. This can prevent damage to the substrate 30B due to the difference in force. As shown in FIG. 15A, the inclination angle α of the small protrusions SC with respect to the conveying direction MD may be 30 degrees to 60 degrees.

[0131] Also, as shown in FIG. 15B, the rear side surface SCr of the small protrusion SC in the conveying direction MD may be inclined with respect to the cross direction CD. The inclination angle β between the rear side surface SCr and the top Ct of the convex portion C may be 90 degrees or more. Therefore, the rear side surface SCr of the small protrusion SC may be inclined so as to be located rearward from the top of the small protrusion SC in the cross direction CD as it approaches the rotation axis CL. This makes it easier for the small protrusion SC that has compressed the substrate 30B to come out of the substrate 30B, and further suppresses micro-damage to the substrate 30B. Note that the front side surface of the small protrusion SC in the conveying direction MD may also be inclined with respect to the cross direction CD. The inclination angle between the front side surface and the top Ct of the convex portion C may be 90 degrees or more. This makes it easier for the small protrusion SC that has compressed the substrate 30B to come out of the substrate 30B.

[0132] Also, as shown in FIG. 16, each of the pair of rolls may have a plurality of roll sections divided in the cross direction CD. For example, the upper roll 121U may have a first upper roll section 121U1, a second upper roll section 121U2, and a third upper roll section 121U3. The lower roll 121L may have a first lower roll section 121L1, a second lower roll section 121L2, and a third lower roll section 121L3. At least one compressed forming section PF may be disposed in each of the plurality of roll sections. Each roll section may be controlled so that it can rotate at a different rotation speed from each other. Thus, in the squeezing process, the rotation speed of each of the plurality of roll sections may be controlled so that the difference in the feed speed of the base material 30B between the plurality of compressed forming sections PF is within 5%.

[0133] Specifically, when the second lower roll section 121L2 having the convex portion C2 rotates at a predetermined speed, the rotation speed of the first lower roll section 121L1 having the concave portion R1 and the third lower roll section 121L3 having the concave portion R3 may be faster than the predetermined speed. Each upper roll section may have the same rotation speed as the opposing lower roll section. When the rotation speed of each lower roll section can only be controlled to be constant, the feed speed of the substrate changes depending on the height of the tops Ct of the convex portions C of the multiple compression forming sections PF (specifically, the convex portions C1, C2, and C3). The substrate 30B is fed relatively quickly from the convex portion C2, and the substrate 30B is fed relatively slowly from the convex portion C1 facing the concave portion R1 and the convex portion C3 facing the concave portion R3. Therefore, the height of the convex portion C is limited so that the difference in the feed speed of the substrate 30B is small. Here, by controlling the rotation speed of each of the multiple roll sections, the height of the convex portion C is not limited, and the difference in the feed speed of the substrate 30B can be kept within 1%, thereby suppressing damage to the substrate 30B caused by deviation in the conveying direction MD.

[0134] 16, there may be a gap G between the multiple roll sections. As a result, the gap G between the compressed forming section PF arranged in a roll section and the compressed forming section PF arranged in another roll section adjacent to the roll section does not press the substrate from both sides in the vertical direction TD, and the force applied to the substrate 30B between these compressed forming sections PF is easily released. This makes it possible to suppress damage to the substrate 30B between these compressed forming sections PF.

[0135] Although the present invention has been described in detail using the above-mentioned embodiment, it is clear to those skilled in the art that the present invention is not limited to the embodiment described in this specification. The present invention can be implemented in modified and altered forms without departing from the spirit and scope of the present invention defined by the description of the claims. Therefore, the description in this specification is intended to be illustrative and does not have any limiting meaning on the present invention. [Explanation of symbols]

[0136] 1: Absorbent articles 30: Absorbent 40: Compression groove 41: First compression groove 42: Second compression groove 43: 3rd compression groove 100: Manufacturing equipment C: Convex part R: Recess PF: Compression forming part PFs: Side compression forming section MD: Transport direction CD: Cross direction TD: Vertical direction

Claims

1. A method for manufacturing an absorbent having a compression groove formed by compression forming part composed of a convex portion and a concave portion facing each other, The process includes a compression step in which the compression groove is formed in the substrate of the absorbent by the convex portion provided on one roll and the concave portion provided on the other roll of a pair of opposing rolls, The compression forming portion has a side compression forming portion which is the part that compresses the base material of the absorbent body among the side of the convex portion and the side of the concave portion, In the compression step, the substrate is compressed at least by the side compression forming section while being fed in the conveying direction. A method for manufacturing an absorbent, wherein the difference between the feed speed of the substrate on one side of the side compression forming section in the vertical direction and the feed speed of the substrate on the other side is within 5%.

2. The method for manufacturing an absorbent according to claim 1, wherein the shortest distance from the top of the convex portion to the bottom of the concave portion is longer than the shortest distance from the side of the convex portion to the bottom of the concave portion.

3. Multiple compression forming sections are arranged at intervals in the intersecting direction. The plurality of compression forming sections each include a first compression forming section and a second compression forming section located next to the first compression forming section in the intersecting direction. The method for manufacturing an absorbent according to claim 1 or 2, wherein the maximum difference between the feed rate of the substrate in the first compression forming section and the feed rate of the substrate in the second compression forming section is within 5%.

4. The lower roll of the pair of rolls, which has a mounting surface on which the substrate is placed, has the mounting surface described above parallel to the intersecting direction, and has an end-parallel surface on which the end of the substrate in the intersecting direction is placed. The method for manufacturing an absorbent according to claim 3, wherein the maximum vertical distance with respect to the end parallel surface of each of the side compression forming portions of the plurality of compression forming portions is 5% or less of the radial distance from the rotation axis of the lower roll to the end parallel surface.

5. The method for manufacturing an absorbent according to claim 3, wherein the spacing between the plurality of compression-forming portions in the aforementioned intersecting direction is greater than or equal to the height of the protrusion in the aforementioned vertical direction.

6. The lower roll of the pair of rolls has a mounting surface on which the substrate is placed, A central region is provided, located in the center when the aforementioned surface is divided into five equal parts in the aforementioned intersecting direction. The method for manufacturing an absorbent according to claim 3, wherein in the compression step, one of the plurality of compression forming sections compresses the base material in the central region.

7. The lower roll of the pair of rolls has a mounting surface on which the substrate is placed, A central region is provided, which is located in the center when the aforementioned mounting surface is divided into five equal parts in the aforementioned intersecting direction, and side regions are provided, which are located on both sides of the central region in the aforementioned intersecting direction. The method for manufacturing an absorbent according to claim 3, wherein in the compression step, the plurality of compression forming units compress the substrate in the side regions without compressing the substrate in the central region.

8. The aforementioned roll has the convex portion of the first compression forming portion and the concave portion of the second compression forming portion, The method for manufacturing an absorbent according to claim 3, wherein the other roll has the recess of the first compression forming portion and the protrusion of the second compression forming portion.

9. The method for manufacturing an absorbent according to claim 3, wherein the lower roll of the pair of rolls, which has a mounting surface on which the substrate is placed, is placed between the first compression forming section and the second compression forming section, and the intermediate surface facing the substrate has an inclined mounting surface that is inclined with respect to the intersecting direction.

10. Non-compression forming sections are provided on both sides in the intersecting direction of the compression forming section for conveying the base material without compression. In the lower roll of the pair of rolls, which has a mounting surface on which the substrate is placed, the non-compression forming portion extends parallel to the intersecting direction from the end of the compression forming portion in the intersecting direction. A method for manufacturing an absorber according to claim 1 or 2, having an extending parallel protruding surface.

11. Multiple compression forming units are arranged at intervals in the intersecting direction. The plurality of compression forming sections include a first compression forming section and a second compression forming section located next to the first compression forming section in the intersecting direction. A non-compression forming section is provided between the first compression forming section and the second compression forming section. In the lower roll, the non-compression forming section is positioned between the first compression forming section and the second compression forming section and has an intermediate surface facing the substrate. In the lower roll, the intermediate surface has the parallel extending surface and the axial parallel surface which is closer to the rotation axis of the lower roll than the parallel extending surface and extends in the intersecting direction. The method for manufacturing an absorber according to claim 10, wherein the average vertical distance from the axial parallel surface to the upper roll of the pair of rolls is longer than the average vertical distance from the parallel extension surface to the upper roll.

12. At the top of the aforementioned protrusion, a plurality of small projections that protrude in the vertical direction are arranged at intervals in the transport direction. The aforementioned small protrusions extend in a direction intersecting the conveying direction while being inclined with respect to the conveying direction. The method for manufacturing an absorbent according to claim 1 or 2, wherein the small protrusions overlap with adjacent small protrusions in the direction of intersection.

13. A method for manufacturing an absorbent according to claim 1 or 2, further comprising a cutting step of cutting the substrate so as to divide the substrate in the conveying direction after the compression step.

14. The process includes a cutting step of cutting the substrate so as to divide it in the transport direction, The method for manufacturing an absorbent according to claim 1 or 2, wherein in the compression step, the compression groove is formed in the cut substrate.

15. Each of the pair of rolls has a plurality of roll sections divided in the intersecting direction, Each of the plurality of roll sections is provided with at least one of the compression forming sections. The method for manufacturing an absorbent according to claim 1 or 2, wherein in the compression step, the rotational speed of each of the plurality of roll sections is controlled so that the difference in the feed speed of the base material is within 5%.

16. The method for manufacturing an absorbent according to claim 15, wherein there are gaps between the plurality of roll sections.

17. A manufacturing apparatus for an absorbent having a compression groove, A pair of rolls facing each other, It has a compression forming section which is composed of opposing convex and concave parts and compresses the base material of the absorbent, The compression forming section forms the compression groove in the substrate using the convex portion provided on one of the pair of rolls and the concave portion provided on the other roll. The compression forming section has a side compression forming section which is the part that compresses the base material, between the side of the convex portion and the side of the concave portion. At least the side compression forming section compresses the substrate while feeding the substrate in the conveying direction, An absorbent manufacturing apparatus in which the difference between the feed speed of the substrate on one side of the side compression forming section in the vertical direction and the feed speed of the substrate on the other side is within 5%.

18. A method for manufacturing an absorbent article comprising an absorbent having a compression groove formed by a compression forming section composed of opposing convex and concave portions, The process includes a compression step in which the compression groove is formed in the base material of the absorbent by the convex portion provided on one roll and the concave portion provided on the other roll of a pair of opposing rolls, The compression forming section has a side compression forming section which is the part that compresses the base material, between the side of the convex portion and the side of the concave portion. In the compression step, the substrate is compressed at least by the side compression forming section while being fed in the conveying direction. A method for manufacturing an absorbent article, wherein the difference between the feed speed of the substrate on one side of the side compression forming section in the vertical direction and the feed speed of the substrate on the other side is within 5%.

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