Absorbent article

Abstract

An absorbent article in which an absorbent body is formed with at least one continuous groove recessed from a non-skin side toward a skin side; a plurality of adhesive non-slip portions having a width direction dimension larger than a front-rear direction dimension are provided on a non-skin side of a back sheet at intervals in the front-rear direction to fix the absorbent article to underpants; the one continuous groove has two or more portions bulging toward the front of the continuous groove and / or two or more portions bulging toward the rear of the continuous groove; for the one continuous groove, a unit length in the front-rear direction and having the same width direction dimension as the absorbent body, an imaginary region, has an area overlapping the one continuous groove of 3% or more, and the one continuous groove has a groove portion not including a center line extending in the front-rear direction in plan view; one non-slip portion overlaps in plan view in a manner including the one continuous groove in the width direction and including a prescribed groove portion in the front-rear direction, or does not overlap the prescribed groove portion.

Description

Technical Field

[0001] This invention relates to an absorbent article. Background Technology

[0002] As for absorbent articles such as sanitary napkins, panty liners, and incontinence pads, there is a known structure that has a liquid-permeable top sheet on the skin side, a liquid-impermeable back sheet on the non-skin side, and an absorbent body disposed between the two sheets. Furthermore, in general, the aforementioned absorbent articles have an anti-slip portion on the non-skin side (the side opposite to the skin side) to prevent the absorbent article from shifting off the underwear during wear.

[0003] The non-slip portion of absorbent articles is mostly formed by applying an adhesive. In addition, various configurations are known, and one type of non-slip portion is formed by applying an adhesive in the form of multiple stripes extending in the width direction of the absorbent article (see, for example, Patent Document 1).

[0004] Patent Document 1: Japanese Patent Application Publication No. 2006-296974 Summary of the Invention

[0005] (The problem this invention aims to solve)

[0006] However, absorbent fabrics, designed to conform to the shape of the body when worn, often have compression grooves formed by locally compressing the top sheet and absorbent core. In this case, even if the compression grooves are formed by compression on the skin side, grooves corresponding to the compression areas on the skin side will also be formed to some extent on the non-skin side (back side) of the absorbent fabric.

[0007] Here, when the aforementioned anti-slip portion is applied across grooves already formed on the non-skin side, air bubbles may enter between the backing and the anti-slip portion, creating gaps and resulting in areas where there is no contact between the backing and the anti-slip portion. In these areas, the adhesion between the anti-slip portion and the underwear is correspondingly stronger than the adhesion between the anti-slip portion and the backing. Therefore, when the absorbent material previously attached to the underwear is peeled off, the anti-slip portion may not remain attached to the backing and may remain on the underwear. This residue is likely to occur in grooves containing components extending in the transverse pulling direction (front-to-back direction), i.e., in areas where grooves containing portions extending along the width are formed, as users typically pull the absorbent material from front to back. Furthermore, as described in Patent Document 1, when the anti-slip portion is formed as multiple stripes extending in the width direction of the absorbent article, the anti-slip portion is prone to break off midway in the front-back direction, thus the anti-slip portion is more likely to remain on the underwear.

[0008] Therefore, in view of the above situation, one embodiment of the present invention aims to solve the problem of preventing the adhesive anti-slip portion from remaining on the underwear when the absorbent material is peeled off.

[0009] (Methods used to solve problems)

[0010] One embodiment of the present invention is an absorbent article comprising a liquid-permeable top sheet on the skin side, a liquid-impermeable back sheet on the non-skin side, and an absorbent body disposed between the top sheet and the back sheet, having a front-back direction corresponding to the front-back direction of the wearer's body, and a width direction orthogonal to the front-back direction, wherein at least one continuous groove is formed in the absorbent body, recessed from the non-skin side to the skin side; on the non-skin side of the back sheet, a plurality of adhesive anti-slip portions with a width dimension larger than the front-back dimension are provided at intervals in the front-back direction for fixing the absorbent article to underwear, wherein the continuous groove has Two or more convex portions facing the front of the continuous groove and / or two or more convex portions facing the rear of the continuous groove; for the continuous groove, an imaginary region having a unit length in the front-rear direction and having the same width dimension as the absorber; the area overlapping the continuous groove is 3% or more; and the continuous groove has a groove portion that does not include a centerline extending along the front-rear direction when viewed from above; the anti-slip portion overlaps with the continuous groove in the width direction and includes the groove portion in the front-rear direction when viewed from above, or does not overlap with the groove portion.

[0011] (The effect of the invention)

[0012] According to one embodiment of the present invention, it is possible to prevent adhesive anti-slip residue from remaining on the underwear when the absorbent material is peeled off. Attached Figure Description

[0013] Figure 1 This is a top view obtained from the skin side, observing an absorbent article according to an embodiment of the present invention.

[0014] Figure 2 This is a top view obtained from the non-skin side, observing an absorbent article according to an embodiment of the present invention.

[0015] Figure 3 It is along Figure 1 A cross-sectional view of line II in the diagram.

[0016] Figure 4 It is along Figure 1 A cross-sectional view of line II-II in the diagram.

[0017] Figure 5 It is a diagram used to illustrate existing technology.

[0018] Figure 6 yes Figure 2 A partially enlarged view is provided to illustrate the specified groove portion.

[0019] Figure 7 This is a top view obtained by observing the absorbent article from the skin side, based on a modified example. Detailed Implementation

[0020] The following is a reference to the appendix. Figure 1 The embodiments of the present invention will be described below. Furthermore, unless otherwise specified, identical or corresponding structures in the figures will sometimes be labeled with the same symbols and their descriptions will be omitted.

[0021] (Basic structure of absorbent materials)

[0022] Figure 1 This is a top view showing the absorbent article 1 according to an embodiment of the present invention, viewed from the skin side, that is, the side opposite to the wearer's skin when the absorbent article 1 is worn. Furthermore, Figure 2 Indicates from and Figure 1 The top view obtained by observing the absorbent material 1 from the opposite side, that is, the side opposite the underwear when worn (the non-skin side). Furthermore, Figure 3 Indicates along Figure 1 A cross-sectional schematic diagram of line II in the diagram. Figure 4 Indicates along Figure 1 A schematic diagram of the cross section of line II-II in the diagram.

[0023] like Figures 1-4 As shown, the absorbent article 1 may have the following structure: a liquid-permeable top sheet 3 on the skin side, a liquid-impermeable back sheet 2 on the non-skin side, and an absorbent body 4 disposed between the two sheets 2 and 3. Therefore, the absorbent article 1 is generally a flat, pad-like structure. Specifically, the absorbent article 1 may be a sanitary napkin, panty liner, incontinence pad, etc., but it is suitable for use as a sanitary napkin. In this instruction manual, a sanitary napkin will be used as an example.

[0024] like Figure 1 and Figure 2As shown, the absorbent article 1 may have a front-to-back direction D1 along the front-to-back direction of the wearer's body when worn, and a width direction D2 orthogonal to the front-to-back direction D1. In this embodiment, the absorbent article 1 has an elongated shape in the front-to-back direction D1 when viewed from above, with the front-to-back direction D1 being the long side direction and the width direction D2 being the short side direction. The total length of the absorbent article 1 (the dimension in the front-to-back direction D1) may be 140 to 420 mm. Furthermore, the width of the absorbent article 1 (the dimension in the width direction D2, excluding any wings or flaps extending from the sides) may be set to 50 to 130 mm.

[0025] Figure 1 In the illustrated embodiment, when viewed from above, with the center line (front-back direction center line) CL drawn along the front-back direction D1, the absorbent article 1 has a shape that is approximately linearly symmetrical about this center line as the axis of symmetry; however, the shape may not be linearly symmetrical. Furthermore, structures other than the shape of the absorbent article 1 (including the density and material of the absorbent body 4, the shape and size of the compression grooves, the shape and size of the anti-slip portion, etc.) may be approximately symmetrical about the front-back direction center line CL as the axis of symmetry, or they may be asymmetrical.

[0026] The backing sheet 2 can be a sheet material that is at least waterproof, such as a sheet material made of olefin resins such as polyethylene or polypropylene. Furthermore, it is possible to use a laminated nonwoven fabric in which a nonwoven fabric is layered on a polyethylene sheet or the like, and a nonwoven fabric in which a waterproof membrane is placed between the polyethylene sheet or the like and the nonwoven fabric to substantially ensure liquid impermeability. Furthermore, from the viewpoint of preventing stuffiness, it is further desirable to use a sheet material that is both waterproof and breathable. As such a waterproof and breathable sheet material, a multi-porous sheet or the like can be obtained by melt-mixing an inorganic filler into an olefin resin such as polyethylene or polypropylene, molding it into a sheet, and then extending it along one or both axes.

[0027] The top sheet 3 can be designed to allow for the rapid permeation of bodily fluids such as menstrual blood, vaginal discharge, and urine. Suitable materials for the top sheet 3 include porous or non-porous nonwoven fabrics and porous plastic sheets. The raw material fibers constituting the nonwoven fabric can be a single type or a combination of two or more fibers, such as: olefins like polyethylene or polypropylene, synthetic fibers like polyester and polyamide, regenerated fibers like rayon or cuprammonium fiber and their blends, and natural fibers like cotton. Furthermore, processing methods for the nonwoven fabric include spunlace, spunbond, thermal bonding, meltblown, and needle punching. Among these methods, spunlace is preferred from the viewpoint of producing soft nonwoven fabrics, spunbond is preferred from the viewpoint of producing nonwoven fabrics with good drape, and thermal bonding is preferred from the viewpoint of producing fluffy and soft nonwoven fabrics. Additionally, composite fibers such as core-sheath type fibers (with a high-melting-point fiber as the core and a low-melting-point fiber as the sheath), side-by-side fibers, and split fibers can also be used.

[0028] The absorbent 4 is not limited, and can be any material capable of absorbing and retaining bodily fluids; preferably, it includes cotton-like pulp and a water-absorbing polymer. As the water-absorbing polymer, superabsorbent polymer powder (SAP), superabsorbent fiber (SAF), and combinations thereof can be used. As the pulp, examples include fibers composed of cellulose fibers and synthetic cellulose fibers, such as chemical pulp and dissolving pulp obtained from wood, and synthetic cellulose fibers such as rayon and acetate. As raw materials for chemical pulp, hardwoods and softwoods can be used, but softwoods are more suitable due to their longer fiber length.

[0029] Synthetic fibers may also be mixed into the absorber 4. As synthetic fibers, olefins such as polyethylene or polypropylene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides such as nylon, and copolymers thereof can be used, and two of these synthetic fibers can be mixed together. Furthermore, composite fibers such as core-sheath type fibers, parallel type fibers, and split type fibers, which have a high-melting-point fiber as the core and a low-melting-point fiber as the sheath, can also be used. Additionally, a fiber that has been surface-treated with a hydrophilic agent to enhance its affinity for body fluids can also be used. The absorber 4 is preferably manufactured by fiber lamination or air-laid method.

[0030] The absorbent body 4 can also be covered by a covering sheet, which is made of crepe paper or non-woven fabric. The covering sheet prevents the absorbent body 4 from wrinkling or tearing and helps it maintain its shape. As the covering sheet, uncolored (i.e., white) crepe paper or non-woven fabric can be used, or it can be colored (e.g., colored to the same color family as the body fluid, or a complementary color to the body fluid). Using a colored covering sheet makes the absorption of body fluid by the absorbent body 4 less noticeable.

[0031] like Figure 1 As shown, the top view of the absorbent body 4 can be an elongated shape with a generally fixed width. Although the width of the absorbent body 4 can vary along the front-to-back direction D1, an absorbent body 4 with a generally fixed width is preferred because it does not complicate the manufacturing process. The absorbent body 4 can have a uniform thickness throughout its entire surface, but the thickness of the absorbent body 4 can also be non-uniform, and it can be locally thinned or thickened. For example, the thickness of the portion Q opposite to the body fluid outlet and its surrounding area, which is opposite to the wearer's body fluid outlet when worn, can be increased to make the absorbent article 1 fit more closely to the body.

[0032] At both ends of the absorbent body 4 in the front-back direction D1, the edge of the back sheet 2 and the edge of the top sheet 3 can be joined together by adhesive, heat sealing or the like. In addition, on both sides of the absorbent article 1, that is, on both sides in the width direction D2, a pair of side sheets 7, 7 are arranged on the skin side (top sheet 3 side) along the front-back direction D1.

[0033] Side panels 7, for purposes such as preventing the penetration of bodily fluids or improving skin feel, may also be made of non-woven fabric raw materials that have undergone appropriate waterproofing or hydrophilic treatment. The raw materials for side panels 7 can be natural fibers, synthetic fibers, recycled fibers, etc. Furthermore, when side panels 7 are waterproofed, this treatment can use waterproofing agents such as silicone-based or paraffin-based agents. Alternatively, the absorbent article may have the following structure: without using side panels 7, the top panel 3 extends to the end of the absorbent article 1 in the width direction D2 and is joined to the back panel 2.

[0034] Furthermore, although the absorbent article 1 according to the illustrated embodiment does not have wings, the absorbent article 1 may also have a pair of wings extending from both sides near the portion where the fluid outlet is located. The wings can be formed by joining the extension portion of the side panel 7 with the extension portion of the back panel 2.

[0035] (Anti-slip part)

[0036] like Figures 1-4As shown, anti-slip portions (9F1, 9F2, 9M, 9B1, 9B2) are formed on the backing 2 side of the absorbent article 1 to more reliably secure the absorbent article 1 to the underwear during wear and prevent the absorbent article 1 from shifting. The anti-slip portions preferably have adhesive properties. Adhesive anti-slip portions can be formed, for example, by coating a fluid, i.e., an adhesive, or by attaching a layer pre-formed with adhesive (adhesive tape, etc.). The adhesive used for the anti-slip portions can be a well-known adhesive, such as a hot-melt adhesive. Examples of its main components include styrene-based polymers, tackifiers, plasticizers, and combinations thereof.

[0037] Examples of the aforementioned styrene-based polymers include styrene-ethylene-butene-styrene block copolymers, styrene-butene-styrene block copolymers, styrene-isobutylene-styrene copolymers, and styrene-butadiene-styrene block copolymers; one or more of these polymers may be used. Furthermore, substances that are solid at room temperature may be used as the aforementioned tackifiers and plasticizers. Examples of tackifiers include C5-based petroleum resins, C9-based petroleum resins, dicyclopentadiene-based petroleum resins, rosin-based petroleum resins, polyterpene resins, and terpene phenolic resins. Examples of plasticizers include monomeric plasticizers such as tricresyl phosphate, dibutyl phthalate, and dioctyl phthalate, as well as polymeric plasticizers such as ethylene polymers and polyesters.

[0038] like Figure 1 and Figure 2 As shown, multiple anti-slip portions are formed. Furthermore, each anti-slip portion is configured to extend along the width direction D2 and be separated in the front-to-back direction D1. In addition, the dimension of the width direction D2 of each anti-slip portion is larger than the dimension of the front-to-back direction D1. Thus, by arranging the anti-slip portions along the width direction D2, it is possible to prevent the anti-slip portions from peeling off the underwear when a pulling force is applied from the legs. Furthermore, by separating the multiple anti-slip portions in the front-to-back direction D1, even if the absorbent material 1 bends in the front-to-back direction D1 to conform to the shape of the body during wear, it is possible to prevent the anti-slip portions from failing to follow the bend and thus hindering the bending of the absorbent material 1.

[0039] The anti-slip portion may include: front anti-slip portions 9F1, 9F2 formed in front of the absorbent article 1, rear anti-slip portions 9B1, 9B2 formed behind the absorbent article 1, and central anti-slip portions 9M, 9M, ... formed between them. Figure 1 and Figure 2In the example shown, the width direction D2 of the multiple anti-slip parts is the same, but the front-to-back direction D1 of the front anti-slip parts 9F1, 9F2 and the rear anti-slip parts 9B1, 9B2 is longer than the front-to-back direction D1 of the central anti-slip parts 9M, 9M, ... This allows for more reliable fixation of the absorbent article 1 to the underwear near the front and rear ends, and also maintains the softness of the central area in the front-to-back direction D1, which bends significantly during wear.

[0040] Furthermore, the weight per unit area of ​​the anti-slip component can be set to 20–50 gsm. The weight per unit area can be the same or different among multiple anti-slip components. However, it is preferable to have equal weight per unit area within a single anti-slip component to avoid complicating the manufacturing process.

[0041] (Groove on the non-skin side)

[0042] In this embodiment, such as Figures 2-4 As shown, the absorbent article 1 has a groove that is recessed from the non-skin side to the skin side. This groove can also be the portion of the absorbent body 4, or the absorbent body 4 and the backing sheet 2 that is recessed towards the skin side. That is, the aforementioned groove recessed from the non-skin side to the skin side includes a state where the absorbent body 4 is recessed and the backing sheet 2 follows that recess, and also a state where the backing sheet 2 is generally flat against the non-skin side of the absorbent body 4 but falls into the recess along the absorbent body 4 and becomes recessed when subjected to certain forces. Such a groove can be pre-formed when the absorbent body 4 is laminated with fibers, or it can be formed by compressing the absorbent body 4, or the absorbent body 4 and the backing sheet 2 together, or the top sheet 3, the absorbent body 4, and the backing sheet 2 together, from the non-skin side. Furthermore, the groove on the non-skin side can also be formed when the absorbent body 4, or the absorbent body 4 and the backing sheet 2 together, or the top sheet 3, the absorbent body 4, and the backing sheet 2 together, are compressed from the skin side, causing strain in the non-skin side due to deformation of the skin side. In most absorbent articles, compression grooves are formed in the absorbent body 4 to facilitate body deformation and control the movement of bodily fluids during wear. Such compression grooves on the skin side can be formed, for example, by placing the absorbent body 4, or a laminate containing a top sheet 3 and the absorbent body 4, or a laminate containing a top sheet 3, the absorbent body 4, and the back sheet 2 between a roller having protrusions corresponding to the shape of the specified compression groove and a roller with no protrusions on the surface opposite the roller, such that the roller having the protrusions is opposite to the skin side, and passing the absorbent body 4 or the laminate between the two rollers.

[0043] Thus, in this embodiment, the groove on the non-skin side can also be a groove formed on the non-skin side along with the formation of a normal compression groove formed from the skin side. In this case, the depth of the groove on the non-skin side is shallower than the depth of the compression groove formed on the skin side. Figure 3 and Figure 4 ).

[0044] like Figure 1 As shown, multiple compression grooves are formed on the skin side. The number, shape, size, and arrangement of the compression grooves can be appropriately determined according to the intended use of the absorbent article 1. Figure 1 In the example shown, a closed central compression groove 11, which is elliptical and elongated in the longitudinal direction D1, is formed as a compression groove. In front of this central compression groove 11, a front first compression groove 12 is formed near the front end, and a front second compression groove 13 is formed behind the front first compression groove 12. Behind the central compression groove 11, a rear first compression groove 14 is formed near the rear end, and a rear second compression groove 15 is formed ahead of the rear first compression groove 14. In this example, the front first compression groove 12 and the rear first compression groove 14 have a front-to-back symmetrical shape, and the front second compression groove 13 and the rear second compression groove 15 also have a front-to-back symmetrical shape. Furthermore, the shape formed by combining the front first compression groove 12 and the front second compression groove 13 is symmetrical to the shape formed by combining the rear first compression groove 14 and the rear second compression groove 15.

[0045] The first compression groove 12 at the front is a continuous compression groove. The first compression groove at the front is shaped such that the vertical direction of the number 8 is aligned with the width direction D2 (or is an infinity symbol). In other words, it is a shape formed by two ellipses arranged in the width direction D2 joining together at their center. On the other hand, the second compression groove 13 at the front is composed of a pair of compression grooves separated in the width direction D2.

[0046] Additionally, compression grooves, such as Figure 1 As shown, it may also have a low compression section and a high compression section formed by compression that is more extensive than the low compression section. Figure 1 In the diagram, low compression is indicated in white, and high compression is indicated in black. For example... Figure 1 As shown, the high-compression section can also be formed intermittently within the low-compression section.

[0047] As mentioned above, due to the formation of Figure 1 As shown, compression grooves are formed on the skin side, so grooves corresponding to the shape of these compression grooves on the skin side are also formed on the non-skin side. Thus, as... Figure 2As shown, the absorbent article 1 has a central groove 11a, a front first groove 12a, a front second groove 13a, a rear first groove 14a, and a rear second groove 15a formed on the non-skin side, which correspond to the shapes of the central compression groove 11, the front first compression groove 12, the front second compression groove 13, the rear first compression groove 14, and the rear second compression groove 15, respectively.

[0048] like Figure 2 As shown, the anti-slip portion is formed in a manner that overlaps with the groove. In the illustrated example, the anti-slip portion overlaps with a portion or all of any one of the central groove 11a, the front first groove 12a, the front second groove 13a, the rear first groove 14a, and the rear second groove 15a.

[0049] Here, when an adhesive anti-slip portion is provided on the non-skin-facing side of the absorbent article 1 where a groove is formed, the anti-slip portion cannot partially or entirely contact the groove, resulting in a gap between the backing sheet 2 and the anti-slip portion. Figure 3 and Figure 4 For ease of explanation, the diagrams show two scenarios: a gap is formed between the front first groove 12a and the anti-slip portion 9F1, and a gap is formed between the central groove 11a and the anti-slip portion 9F2. However, the gap between the back sheet 2 and the anti-slip portion may not be formed throughout the entire groove, but rather in a portion or a very small part of the groove. In this case, tiny air bubbles may be trapped between the back sheet 2 and the anti-slip portion.

[0050] Thus, if a groove is formed on the non-skin side of the absorbent article 1, areas where the backing sheet 2 and the anti-slip portion do not directly contact each other are easily created. Consequently, the adhesive force of the anti-slip portion decreases. Therefore, in the case of a prior art absorbent article 1' that does not have the specific configuration relationship between the groove 10a' and the anti-slip portion 9' on the non-skin side of this embodiment (… Figure 5 (a) When the absorbent material 1', which is attached to the underwear S during wearing, is to be removed from the underwear S, the anti-slip part 9' will be pulled and torn in areas where the adhesion between the underwear S and the anti-slip part 9' is greater than that between the back panel 2' and the anti-slip part 9'. Therefore, a portion of the anti-slip part may remain on the underwear S as an anti-slip piece r. Figure 5 (b) Since the direction in which the absorbent article 1 is peeled off is the front-to-back direction D1 (e.g., the direction starting from the front), for grooves having a shape that extends in the width direction D2 orthogonal to the front-to-back direction D1, or grooves containing a number of components in the width direction D2, such a phenomenon (also known as residual adhesive) is likely to occur when the anti-slip part overlaps with it.

[0051] In contrast, the inventors have discovered that by improving the arrangement of the anti-slip portion in a groove containing a plurality of components in the width direction D2, or in a defined groove portion containing a plurality of components in the width direction D2, it is possible to prevent the anti-slip portion from remaining on the underwear (preventing adhesive residue). Specifically, in this embodiment, when the anti-slip portion is overlapped on the non-skin side of the groove, it is arranged such that the groove portion containing a plurality of components in the width direction D2 is included in the front-to-back direction D1 when viewed from above. Therefore, since the anti-slip portion can be positioned in front of and behind the groove, the cohesive force of the anti-slip material can be applied from front to back across the groove. Therefore, even at the location where the groove is formed, the adhesion between the backing and the anti-slip part is weakened. The anti-slip part in front of and behind the groove, which is not opposite to the groove, can be pulled by the cohesive force of the anti-slip part material to the anti-slip part that is positioned opposite the groove. Thus, the anti-slip part will not break in the groove and can prevent the anti-slip part from remaining on the underwear.

[0052] Here, refer to Figure 6 The determination of the aforementioned groove portion is explained. Figure 6 express Figure 2 An enlarged view of the portion forming the first front groove 12a and the second front groove 13a. As described above, the first front groove 12a is a continuous groove containing two elliptical rings with major axes in the width direction D2. That is, this continuous groove (first front groove 12a) has two or more convex portions facing the front of the continuous groove and two or more convex portions facing the rear of the continuous groove. In other words, it can have the following shape: on the front or rear side of the continuous groove, the tangent drawn from the outer edge has two or more points parallel to the width direction D2. In the case of such a continuous groove with two or more convex portions facing the front or rear, when the absorbent article 1 is peeled from the underwear in the front-back direction D1, two or more locations where the adhesive force weakens will occur simultaneously or at close points between the backing 2 and the anti-slip portion. Figure 5 In the case of the anti-slip portion 9' shown, the anti-slip portion 9' will tear in more than two places along the width direction D2, which will easily result in adhesive residue. Therefore, there is a need to find a way to improve the configuration of the anti-slip portion overlapping on a continuous groove with two or more convex portions facing forward or backward.

[0053] Furthermore, the shape of the aforementioned continuous groove is preferably symmetrical from left to right (linearly symmetrical with the center line CL in the front-rear direction as the line of symmetry). Additionally, when there are two or more forward-convex portions, the front ends of these two or more convex portions are preferably aligned in the front-rear direction D1 (located at the same position in the front-rear direction D1). Similarly, when there are two or more rearward-convex portions, the rear ends of these two or more convex portions are preferably aligned in the front-rear direction D1 (located at the same position in the front-rear direction D1).

[0054] Furthermore, such as Figure 6 As shown, within a continuous groove (first front groove 12a) having the specific shape described above, an imaginary region IA having a unit length in the front-rear direction D1 and having the same width dimension as the absorber, overlaps with a continuous groove 12a in an area of ​​3% or more, and the portion that does not include the front-rear direction centerline CL when viewed from above is defined as a specified groove portion pg. Figure 6 In the diagram, the specified groove portion pg is indicated in black. Furthermore, from the viewpoint of ensuring the softness of the absorber 4, the area overlapping the aforementioned imaginary region IA with a continuous groove 12a is preferably 30% or less. Moreover, for example, with a continuous groove (e.g., the front first groove 12a), when a rectangular imaginary region IA (having dimensions in the front-rear direction D1 that are the same as or exceed the width of the continuous groove, and having two ends in the width direction D2 at both ends of the absorber 4) is overlapped on a continuous groove, if there is a groove portion pg whose area overlaps with the imaginary region IA is 3% or more relative to the area of ​​the imaginary region IA, the anti-slip portion 9F1 can be formed in a way that includes the groove portion pg in the front-rear direction D1 when viewed from above. However, the groove portion pg is designed not to include the front-rear direction centerline CL when viewed from above. Furthermore, the dimension D2 of the width direction of the groove portion pg can be greater than the width of a continuous groove, and preferably more than twice the width of a continuous groove.

[0055] like Figure 6 As shown, the number of groove portions pg existing in a continuous groove can be more than two, or it can be one.

[0056] In this embodiment, an anti-slip portion is formed in a predetermined groove portion of a continuous groove, such that the groove portion is included in the front-rear direction D1. And, for example... Figure 6 As shown, the anti-slip portion 9F1 is preferably formed in a manner that exceeds the dimension of the groove portion pg in the front-rear direction D1 or the width of the groove of the continuous groove 12a, and extends beyond the front and rear of the groove portion pg and includes the groove portion pg in the front-rear direction D1.

[0057] Thus, in front of and behind the designated groove portion pg, the anti-slip portion extends beyond the front and rear of the groove portion pg by a dimension greater than D1 in the front-rear direction D1. Therefore, when the absorbent article 1 is peeled off from the underwear, for example from front to back, the anti-slip portion portion opposite to the groove can be pulled along the portion in front of and behind the groove portion pg that does not have an anti-slip portion opposite to the groove, thereby further preventing the anti-slip portion from remaining on the underwear. Here, the length of the anti-slip portion extending forward from the front end of the groove portion pg, or the length of the portion extending backward from the rear end of the groove portion pg, is preferably 0.8 to 2.5 mm, more preferably 1.0 to 2.0 mm.

[0058] In addition, such as Figure 6 As shown, the anti-slip portion 9F1, which overlaps in a manner that surrounds the groove portion pg in the front-to-back direction D1, overlaps in a manner that surrounds the entire continuous groove 12a in the width direction D2. That is, when the anti-slip portion 9F1 overlaps with the groove portion pg, the continuous groove 12a is not exposed from the anti-slip portion 9F1 in the width direction D2 when viewed from above. As a result, the cohesive force of the material of the aforementioned anti-slip portion also acts in the width direction D2, so when the absorbent article 1 is peeled from the underwear, the effect of the anti-slip portion, which has a weaker adhesion to the backing sheet 2 due to its opposition to the specified groove portion pg, can be improved.

[0059] In addition, Figure 6 In the example, the groove portion pg can be considered as the portion of the continuous groove between the tangent in the width direction D2 parallel to the outer periphery of the foremost continuous groove in the absorbent article 1 and the tangent in the width direction D2 parallel to the inner periphery of the continuous groove. Furthermore, in the rearmost continuous groove in the absorbent article 1, the groove portion pg can be considered as the portion of the continuous groove between the tangent in the width direction D2 parallel to the outer periphery of the rear of the continuous groove and the tangent in the width direction D2 parallel to the inner periphery of the continuous groove. For such a groove portion pg, it is preferable to provide the anti-slip portion in such a way that the sum of the largest width direction D2 dimensions of the groove portion pg is at least 20% of the width direction D2 dimension of the anti-slip portion overlapping the continuous groove.

[0060] Furthermore, in this embodiment, the anti-slip portion can also be formed in a way that completely does not overlap with the designated groove portion pg when viewed from above. This is because if the anti-slip portion does not overlap with the groove portion pg at all, the aforementioned problem of anti-slip residue (adhesive residue) on the underwear will not occur. For example, Figure 2The rear first groove 14a has the same shape as the front first groove 12a, and overlaps with the anti-slip portion 9B1. However, on the side of the rear first groove 14a near the center in the front-rear direction D1 (front side), there is no overlap of the anti-slip portion 9B1. Therefore, for the rear first groove 14a, there is no need to worry about residual adhesive being generated in the specified groove portion pg on the side near the center in the front-rear direction D1. Figure 5 (b)).

[0061] According to this embodiment, an anti-slip portion is provided such that, when viewed from above, it can include a continuous groove in the width direction D2 and a predetermined groove portion pg in the front-to-back direction D1, or it can be provided without overlapping the groove portion pg. Regarding the relationship between this anti-slip portion and the continuous groove on the non-skin side, the anti-slip portion can be formed in any area of ​​the absorbent article 1, but it is preferably provided at the front of the absorbent article 1, especially in front of the portion Q opposite to the body fluid outlet. That is, regarding the above relationship, i.e., the anti-slip portion is provided such that it can include a continuous groove in the width direction D2 and a predetermined groove portion pg in the front-to-back direction D1, or it can be provided without overlapping the groove portion pg, if... Figure 2 In the example shown, it is preferable to form at least the anti-slip portion in the front first groove 12a. When peeling the absorbent article 1 from the underwear, since most users peel it from the front, the peeling action at the front is prone to being subjected to a strong force abruptly, which interrupts the cohesive force of the anti-slip portion and increases the possibility that the anti-slip portion will remain on the underwear. Therefore, by forming a continuous groove with the anti-slip portion in the aforementioned prescribed configuration at the front, the aforementioned residue can be effectively avoided.

[0062] Furthermore, to prevent the anti-slip portion from remaining on the underwear, methods such as increasing the unit area weight of the adhesive anti-slip portion or expanding the coating area of ​​the anti-slip portion, for example, coating it on the entire surface of the back side 2, have been considered. This is because by increasing the unit area weight of the anti-slip portion or expanding the coating area of ​​the anti-slip portion, the cohesive force of the anti-slip portion in the surface direction can be improved and the anti-slip portion can be prevented from breaking. However, increasing the unit area weight of the anti-slip portion increases costs and may impair the softness of the absorbent material, affecting the wearing experience. Therefore, according to this embodiment, by forming the anti-slip portion in a predetermined configuration relative to the continuous groove, or by ensuring that it does not overlap on a predetermined groove portion comprising a plurality of components in the width direction D2, it is possible to avoid adhesive residue even without changing the unit area weight and coating area of ​​the anti-slip portion.

[0063] The dimension of the anti-slip portion in the front-back direction D1 is determined based on the dimension of the groove portion pg in the front-back direction D1 of the continuous groove, and is preferably 7 to 50 mm. By setting the dimension of the anti-slip portion in the front-back direction D1 within the above range, the aforementioned effect of avoiding adhesive residue can be achieved, while maintaining the softness of the absorbent article 1.

[0064] (Example of an absorbent material)

[0065] Figure 7 This is a top view showing the absorbent article 1A as seen from the skin side, according to a modified example. The structure of absorbent article 1A is basically the same as that of absorbent article 1 ( Figure 1 While the absorbent articles are similar in size, they differ from absorbent article 1 in the dimensions of the absorbent material and the arrangement of the anti-slip portions in the central region along the front-to-back direction D1. Absorbent article 1A is slightly longer than absorbent article 1. Furthermore, in absorbent article 1A, the front anti-slip portions 9F1, 9F2 and the rear anti-slip portions 9B1, 9B2 are arranged the same as in absorbent article 1, but the dimensions of the central anti-slip portions 9M, 9M, ... in the width direction D2 are smaller than those of the front anti-slip portions 9F1, 9F2 and the rear anti-slip portions 9B1, 9B2. Therefore, the central region along the front-to-back direction D1 exhibits higher softness, which is desirable.

[0066] Furthermore, in absorbent article 1A, the central anti-slip portions 9M, 9M, ..., when viewed from above, do not overlap with the central compression groove 11 and are arranged on the non-skin side in a manner that does not overlap with the central groove (not shown). Therefore, in this example, in addition to obtaining absorbent article 1 ( Figure 1 In addition to the effect of the anti-slip material, it is also difficult for the anti-slip material to remain on the underwear near the area where the central compression groove 11 is formed.

[0067] (Regarding manufacturing)

[0068] Furthermore, there is no particular limitation on the method of setting the anti-slip part on the backing sheet 2. It can be done by applying a liquid adhesive, for example, using a grate applicator, spray applicator, spiral spray gun, hot melt glue gun, or other applicating device. In this case, the adhesive can be dispensed from the applicator, which is already fixed in position, to form the anti-slip part extending along the width direction D2 of the absorbent article 1, which is being transported along the width direction D2 by a conveyor belt or other transport device.

[0069] Alternatively, the adhesive can be applied to the backing sheet 2 without first applying it to the packaging sheet or release sheet opposite to the backing sheet 2 during individual packaging, and then the backing sheet 2 of the absorbent article 1 can be positioned opposite the packaging sheet or release sheet. Here, by pre-demolding the packaging sheet or release sheet, when the absorbent article 1 is peeled off from the packaging sheet or release sheet during use, the adhesive will transfer to the backing sheet 2 of the absorbent article 1, thus functioning as an anti-slip part.

[0070] Furthermore, when applying adhesive to the release liner, the backing sheet 2 can be simply overlapped on the release liner already coated with adhesive, and then the laminate of the absorbent body 4 with compression grooves and the top sheet 3 can be placed to complete the absorbent article 1. In this case, even if the laminate of the absorbent body 4 and the top sheet 3 is compressed from the skin side, it is difficult for gaps to be generated between the anti-slip part and the backing sheet 2, so it is more ideal.

[0071] The following describes specific embodiments of the present invention.

[0072] (Note 1)

[0073] The embodiment of Note 1 is an absorbent article comprising a liquid-permeable top sheet on the skin side, a liquid-impermeable back sheet on the non-skin side, and an absorbent body disposed between the top sheet and the back sheet. It has a front-back direction corresponding to the front-back direction of the wearer's body, and a width direction orthogonal to the front-back direction. In the absorbent body, at least one continuous groove is formed that is recessed from the non-skin side to the skin side. On the non-skin side of the back sheet, a plurality of adhesive anti-slip portions with a width dimension larger than the front-back dimension are provided at intervals in the front-back direction to secure the absorbent article to underwear. The continuous groove has... Two or more convex portions facing the front of the continuous groove and / or two or more convex portions facing the rear of the continuous groove; for the continuous groove, an imaginary region having a unit length in the front-rear direction and having the same width dimension as the absorber, the area overlapping the continuous groove is 3% or more, and the continuous groove has a groove portion that does not include a centerline extending along the front-rear direction when viewed from above; the anti-slip portion overlaps with the continuous groove in the width direction and includes the groove portion in the front-rear direction when viewed from above, or does not overlap with the groove portion.

[0074] According to the embodiment of Note 1 above, a continuous groove on the non-skin side (back panel side) of the absorbent article, even if it has two or more forward-facing protrusions and / or two or more rearward-facing protrusions and has a defined groove portion containing a number of components in the width direction, can prevent or reduce the adhesive anti-slip residue on the underwear by having the anti-slip portion overlap the groove portion when viewed from above in a defined configuration, or by using a method that prevents the anti-slip portion from overlapping the groove portion when viewed from above.

[0075] In the former case, where the anti-slip portion overlaps the aforementioned groove portion, the anti-slip portion extends in a manner that includes a continuous groove in the width direction and a groove portion in the front-to-back direction when viewed from above. Therefore, the anti-slip portion is positioned in front of and behind the aforementioned groove portion of the continuous groove, allowing the cohesive force of the anti-slip material to act in the front-to-back direction across the aforementioned groove portion. Consequently, when peeling the absorbent material from the underwear in the front-to-back direction (e.g., from front to back), even if the anti-slip portion opposite to a part of the continuous groove (i.e., the groove portion) has weak adhesion to the backsheet, the anti-slip portion configured to maintain adhesion to the backsheet by being opposite the portion in front of and behind the aforementioned groove portion (the portion without a groove) can pull the anti-slip portion configured to be opposite the specified groove portion, thus reducing or preventing the anti-slip portion in the groove portion from leaving the backsheet and transferring to the underwear. Furthermore, since the anti-slip part is designed to include a continuous groove in the width direction, the cohesive force of the anti-slip part can also be easily exerted in the width direction, which can prevent the anti-slip part from breaking off at the position opposite to the continuous groove and remaining on the underwear.

[0076] Furthermore, in the latter case where the anti-slip part does not overlap with the groove portion as specified above, since the anti-slip part is not originally opposite to the groove portion, there is no need to worry about the anti-slip part transferring from the back panel to the underwear.

[0077] (Note 2)

[0078] In the embodiment of Note 2, the anti-slip portion, when viewed from above, includes the entirety of the continuous groove.

[0079] According to the embodiment described in Note 2 above, since the anti-slip portion comprises a continuous groove when viewed from above, it can extend around the periphery of the specified groove portion in areas not opposite to the groove. Because the cohesive force of the anti-slip material functions continuously in the planar direction, this structure allows the cohesive force of the anti-slip material to act over a wider area. Therefore, when the absorbent material is removed from the underwear, it is further possible to prevent the anti-slip portion from breaking off at the specified groove portion and transferring onto the underwear.

[0080] (Note 3)

[0081] In the embodiment of Note 3, the front-to-back dimension of the anti-slip portion is 7 to 50 mm.

[0082] According to the embodiment in Note 3 above, since the anti-slip portion has a predetermined front-to-back dimension, it can enhance the effect that the anti-slip portion opposite to the continuous groove is pulled by the anti-slip portion that is continuous in front and behind it and is not opposite to the continuous groove, while reducing the possibility that the softness of the absorbent article may be impaired due to the anti-slip portion being too long in the front-to-back direction.

[0083] (Note 4)

[0084] In the embodiment of Note 4, the anti-slip portion extends forward or backward beyond the groove portion in a manner greater than or equal to the longitudinal dimension of the groove portion.

[0085] According to the embodiment described in Note 4 above, the anti-slip portions disposed before and after the groove portion specified above can pull on the anti-slip portions opposite to the continuous groove, thereby further improving the effect of preventing anti-slip residue from remaining on the underwear.

[0086] (Note 5)

[0087] In the embodiment of Note 5, the continuous groove has a shape corresponding to the compression groove formed on the skin side.

[0088] According to the embodiment described in Note 5 above, the continuous grooves are grooves formed on the non-skin side of the absorbent article in conjunction with the formation of compression grooves (adaptive embossing) on ​​the skin side, and corresponding to the shape of the compression grooves, so the depth is suppressed to be relatively shallow. Even with such shallow grooves, when the anti-slip portion is placed on the non-skin side of the absorbent article, air bubbles will be trapped, creating a gap between the backing and the anti-slip portion. However, by providing the anti-slip portion in a prescribed configuration as described above in the embodiment described in Note 1 above, it is possible to prevent the anti-slip portion from remaining on the underwear. Since most absorbent articles have compression grooves formed on the skin side, this embodiment can address the problem of most absorbent articles having anti-slip portion residue remaining on the underwear.

[0089] (Note 6)

[0090] In the embodiment of Note 6, the absorbent article has a fluid outlet opposing portion opposite to the wearer's fluid outlet, and the continuous groove is formed at least forward of the fluid outlet opposing portion.

[0091] When removing absorbent material from underwear, most users tend to grasp the front of the absorbent material and peel it back. This initial peeling motion is often rapid, resulting in the anti-slip portion remaining on the underwear. According to the embodiment described in Note 6 above, since the anti-slip portion at least at the front has the same configuration as described in Note 1, the effect of this embodiment can be achieved more effectively.

[0092] This application claims priority to Japanese Patent Application No. 2021-158364, filed on September 28, 2021, the entire contents of which are incorporated herein by reference.

[0093] Explanation of reference numerals in the attached figures

[0094] 1. 1A Absorbent Items

[0095] 2 back pieces

[0096] 3 top films

[0097] 4 absorbers

[0098] 7 side pieces

[0099] 9, 9F1, 9F2, 9B1, 9B2, 9M adhesive anti-slip parts

[0100] 11 Central Compression Groove

[0101] 12 First compression groove in front

[0102] 13 Second Compression Groove

[0103] 14 Rear First Compression Groove

[0104] 15 Rear Second Compression Groove

[0105] 11a Central Trench

[0106] 12a First trench

[0107] 13a Second trench

[0108] 14a rear first trench

[0109] Second trench behind 15a

[0110] D1 Front and rear directions

[0111] D2 Width Direction

[0112] The specified groove portion in the pg continuous groove

[0113] Q is the part opposite to the body fluid discharge outlet.

Claims

1. An absorbent article comprising a liquid-permeable top sheet on the skin side, a liquid-impermeable back sheet on the non-skin side, and an absorbent body disposed between the top sheet and the back sheet, and having a front-back direction corresponding to the front-back direction of the wearer's body, and a width direction orthogonal to the front-back direction, wherein, The absorbent body has at least one compression groove recessed from the skin side to the non-skin side, and at least one continuous groove recessed from the non-skin side to the skin side, the continuous groove having a shape corresponding to the compression groove. On the non-skin side of the back panel, a plurality of adhesive anti-slip portions are provided at intervals in the front-to-back direction, with a width dimension larger than the front-to-back dimension, to secure the absorbent material to the underwear. The continuous groove extends across a centerline extending in the front-rear direction, beyond more than half the width dimension of the absorber, and has two or more convex portions facing forward of the continuous groove and / or two or more convex portions facing backward of the continuous groove. The continuous groove has a groove portion at the convex portion, which overlaps with a rectangular imaginary region and, when viewed from above, does not include a centerline extending along the front-back direction. The width dimension of the imaginary region is the same as that of the absorber, and its front-back dimension is the same as the width of the continuous groove. The area of ​​the groove portion that overlaps with the imaginary area is more than 3% of the area of ​​the imaginary area, and one of the plurality of anti-slip portions overlaps on the continuous groove in such a way that it includes the continuous groove in the width direction and the groove portion in the front-back direction when viewed from above.

2. The absorbent article according to claim 1, wherein, The anti-slip portion overlaps the continuous groove in such a manner that it includes the entire continuous groove when viewed from above. The anti-slip portion overlapping the continuous groove is arranged such that the sum of the largest width dimensions of the groove portions of the two or more convex portions is more than 20% of the width dimension of the anti-slip portion.

3. The absorbent article according to claim 1, wherein, The front-to-back dimension of the anti-slip part is 7 to 50 mm.

4. The absorbent article according to any one of claims 1 to 3, wherein, The anti-slip portion extends forward or backward beyond the groove portion in a manner that is greater than or equal to the front-to-back dimension of the groove portion.

5. The absorbent article according to any one of claims 1 to 3, wherein, The absorbent article has a portion opposite to a bodily fluid outlet, which is opposite to the wearer's bodily fluid outlet. The continuous groove is formed at least in front of the portion opposite the body fluid outlet.

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