Individually packaged absorbent articles

Abstract

To provide an individually packaged absorbent article that reduces a residual seal in a packaging sheet after being opened.SOLUTION: There is provided an individually packaged absorbent article including a packaging sheet and an absorbent article individually packaged by the packaging sheet. The packaging sheet has a vertical direction and a horizontal direction orthogonal to the vertical direction. The packaging sheet is folded in the vertical direction at a first folding line and a second folding line along the horizontal direction. A seal portion is formed in marginal parts in the horizontal direction respectively. The seal portion includes a weak seal portion whose bonding strength is lower than those of the other parts of the seal portion in at least one of a range up to 20 mm from the first folding line in the vertical direction, and a range up to 20 mm from the second folding line in the vertical direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to individually packaged absorbent articles.

Background Art

[0002] Generally, absorbent articles such as sanitary napkins, panty liners, incontinence pads, etc. are provided as individually packaged absorbent articles (individual packages) that are individually packaged and sealed with a packaging sheet for reasons such as hygiene during storage and convenience during carrying.

[0003] As a form of individually packaged absorbent articles, after folding the packaging sheet together with the absorbent article into an inner triple fold along a folding line along the transverse direction in the longitudinal direction of the packaging sheet, the transverse edges of both sides of the packaging sheet are often sealed. For example, as described in Patent Document 1, the seal portion formed by sealing is usually continuously formed in the longitudinal direction with the same configuration from the end to the end in the longitudinal direction, that is, from one folding line to the other folding line.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When opening individually packaged absorbent materials, the user peels apart the packaging sheets that are joined together at the seal and unfolds the packaging sheet. However, when opening individually packaged absorbent materials in the conventional way, where the seal is formed from one end to the other vertically (from one fold line to the other), it is often difficult to completely peel apart the packaging sheet, and the seal remains near the fold line. If the seal remains (the packaging sheets are not completely peeled apart), a fold line or crease remains on the packaging sheet even after opening. Therefore, when attempting to wrap a used absorbent material with a packaging sheet obtained from a newly opened individually packaged absorbent material, the packaging sheet may be folded or curled, which can hinder the wrapping process. Thus, there is a need for a configuration that eliminates or reduces the remaining seal portion (also called seal residue) on the packaging sheet after opening the individually packaged absorbent material.

[0006] In view of the above, one aspect of the present invention aims to provide an individually packaged absorbent article that reduces seal residue on the packaging sheet after opening. [Means for solving the problem]

[0007] A first aspect of the present invention is a individually packaged absorbent article comprising a packaging sheet and an absorbent article individually packaged by the packaging sheet, wherein the packaging sheet has a longitudinal direction and a transverse direction perpendicular to the longitudinal direction, the packaging sheet is folded in the longitudinal direction along a first fold line and a second fold line along the transverse direction, a seal portion is formed at each of the transverse edges, and in the seal portion, a weak seal portion is provided in at least one of the longitudinal range from the first fold line to 20 mm and the longitudinal range from the second fold line to 20 mm, having a lower bonding strength than the rest of the seal portion.

[0008] According to the first embodiment described above, a weak seal portion with low bonding strength is formed in a predetermined range from the first fold line and / or the second fold line, making it easier to eliminate the seal portion near the fold line without applying a large force. This reduces the amount of seal remaining after opening, and allows the packaging sheet to be unfolded flat without wrinkles or other issues that may occur due to seal residue. By reducing the amount of seal residue on the packaging sheet, if the packaging sheet is to be used to wrap and dispose of used absorbent materials, curling of the packaging sheet can be suppressed, allowing for a smoother wrapping process.

[0009] In a second aspect of the present invention, an individually packaged absorbent article comprises a packaging sheet and an absorbent article individually packaged by the packaging sheet, wherein the packaging sheet has a longitudinal direction and a transverse direction perpendicular to the longitudinal direction, the packaging sheet is folded in the longitudinal direction along a first fold line and a second fold line along the transverse direction, a seal portion is formed on each of the transverse edges, and an unsealed portion is provided in at least one of the longitudinal range from the first fold line to 20 mm and the longitudinal range from the second fold line to 20 mm.

[0010] According to the second embodiment described above, since there is a portion within a predetermined range from the first fold line and / or the second fold line in which no seal portion is formed, the seal portion can be easily removed up to the vicinity of the fold line without applying much force (the packaging sheet can be peeled off). This reduces the amount of seal portion remaining after opening, and the packaging sheet can be unfolded flat without wrinkles or other issues that may occur due to seal residue. When the packaging sheet is to be used to wrap and dispose of used absorbent materials, the wrapping action can be performed smoothly because the curling of the packaging sheet is suppressed.

[0011] Furthermore, the non-sealed portion can also serve as an air vent during manufacturing. For example, if a large, sudden force is applied to an individually packaged absorbent article from the outside during manufacturing or packaging, the air may be compressed, further pressing against the seal and potentially damaging it (causing the packaging of the absorbent article to burst). Such problems can be avoided by allowing air to escape properly through the non-sealed portion.

[0012] In a third aspect of the present invention, the sealing portion includes a plurality of joints spaced apart from each other, and the lateral inner ends of the joints included in the weak sealing portion are closer to the lateral edge of the packaging sheet than the lateral inner ends of the other portions.

[0013] As mentioned above, if there is any remaining seal, a crease or fold remains, making it difficult to flatten the packaging sheet. The effect of the remaining seal on the crease or fold is greater the closer the remaining seal is to the center in the horizontal direction. According to the third embodiment described above, the horizontal inner end of the joint included in the weak seal portion is close to the horizontal edge of the packaging sheet, and the weak seal portion is positioned further outward in the horizontal direction compared to the inner ends of other parts of the seal area. Therefore, even if the vertical unfolding of the packaging sheet is insufficient when opening and the weak seal portion remains, a crease or fold is less likely to remain.

[0014] In a fourth aspect of the present invention, the sealing portion includes a plurality of joints spaced apart from each other, and the density of the joints in the weak sealing portion is less than the density of the joints in the other portion.

[0015] As a result of the fourth embodiment described above, the density of the joints in the weakly sealed area is reduced, so less force is required to eliminate the weakly sealed area (the force required to peel off the packaging sheet), making it less likely for seal residue to remain near the fold line. Therefore, for example, the force applied when peeling off the packaging sheet from the other parts of the sealed area (also called the main sealed area) allows the packaging sheet in the weakly sealed area to be easily peeled off as well. The user can then flatten the packaging sheet without having to be particularly conscious of eliminating the seal up to the fold line.

[0016] In a fifth aspect of the present invention, the weak seal portion is formed in the region where two packaging sheets are stacked.

[0017] At the lateral edges of individually packaged absorbent articles, the number of overlapping packaging sheets varies depending on the location. The greater the number of overlapping packaging sheets, the stronger the bonding strength between the packaging sheets at the sealed area in that location, and the smaller the number of overlapping sheets, the weaker the bonding strength. In the fifth embodiment described above, by forming a weak seal area in the region where two packaging sheets are overlapped, the bonding strength of the weak seal area can be further reduced. [Effects of the Invention]

[0018] According to one aspect of the present invention, it is possible to provide individually packaged absorbent articles that reduce seal residue on the packaging sheet after opening. [Brief explanation of the drawing]

[0019] [Figure 1] This is a plan view of an individually packaged absorbent article according to the first embodiment of the present invention. [Figure 2] This is a plan view showing the individual absorbent article in Figure 1 before it is folded, or a plan view showing the individual absorbent article in Figure 1 unfolded. [Figure 3] This is a cross-section of line II in Figure 1. [Figure 4] This is a cross-section along line II-II in Figure 1. [Figure 5] This is an enlarged example of the seal portion in Figure 1. [Figure 6]It is a figure showing a modification example of a seal part. [Figure 7] It is a figure showing another modification example of a seal part. [Figure 8] It is a figure showing yet another modification example of a seal part. [Figure 9] It is a plan view of an individually packaged absorbent article according to the second embodiment of the present invention. [Figure 10] It is a plan view of an individually packaged absorbent article according to the third embodiment of the present invention. [Figure 11] It is a cross-section taken along line IV-IV of FIG. 10. [Figure 12] It is a cross-section taken along line V-V of FIG. 1.

Mode for Carrying Out the Invention

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing, unless otherwise specified, the same or corresponding components may be denoted by the same reference numerals and the description thereof may be omitted.

[0021] <First Embodiment> (Individually Packaged Absorbent Article) FIG. 1 shows a plan view of an individually packaged absorbent article 100. FIG. 2 shows a plan view of the absorbent article in the unfolded state or before folding, or the absorbent article and the packaging sheet, as viewed from the inner surface of the packaging sheet 10 or from the skin side of the absorbent article 1. Further, FIG. 3 shows a cross-section taken along line I-I of FIG. 1, and FIG. 4 shows a cross-section taken along line II-II of FIG. 1.

[0022] As shown in FIGS. 1 to 4, the individually packaged absorbent article 100 according to this embodiment includes a packaging sheet 10 and an absorbent article 1 individually packaged by the packaging sheet 10. As shown in FIG. 2, the packaging sheet 10 may have an elongated shape in the unfolded state or before folding, and has a longitudinal direction (lengthwise direction) D1 and a transverse direction (widthwise direction) D2 orthogonal to the longitudinal direction. Also, the longitudinal direction D1 and the transverse direction D2 of the packaging sheet 10 respectively correspond to the longitudinal direction and the transverse direction of the absorbent article 1.

[0023] (Absorbent Article) In this embodiment, the absorbent article 1 packaged by the packaging sheet 10 may be a flat, elongated article designed to be worn facing the outlet for bodily fluids (menstrual blood, vaginal discharge, urine, etc.). Specific examples of the absorbent article 1 may include sanitary napkins, panty liners (discharge liners), and light incontinence pads. This specification will describe embodiments based on the example of sanitary napkins.

[0024] The absorbent article 1 may have, for example, a liquid-permeable top sheet 3, a liquid-impermeable back sheet (not shown), and an absorbent material 4 placed between the top sheet 3 and the back sheet, as shown in Figure 2.

[0025] As the backsheet, a sheet material having at least water-impermeable properties can be used, such as an olefin resin sheet made of polyethylene or polypropylene. Laminated nonwoven fabrics, such as polyethylene sheets laminated with nonwoven fabric, or laminated nonwoven fabric sheets with a waterproof film interposed to ensure substantially liquid impermeability can be used. Materials with moisture permeability may also be used.

[0026] As the top sheet 3, perforated or non-perforated nonwoven fabrics or porous plastic sheets are preferably used. As material fibers constituting the nonwoven fabric, for example, olefins such as polyethylene and polypropylene, synthetic fibers such as polyester and polyamide, regenerated fibers such as rayon and cupro, and blends thereof, as well as natural fibers such as cotton can be used individually or in combination of two or more types.

[0027] The absorbent material 4 is not limited to any material that can absorb and retain bodily fluids, but it is preferable to include cotton-like pulp and a superabsorbent polymer. As the superabsorbent polymer, superabsorbent polymer granules (SAP), superabsorbent polymer fibers (SAF), and combinations thereof can be used. As the pulp, examples include cellulose fibers such as chemical pulp and dissolved pulp obtained from wood, and artificial cellulose fibers such as rayon and acetate.

[0028] The thickness of the absorbent material 4 may be 0.5 to 25 mm. The absorbent material 4 may also have a structure in which the area corresponding to the body fluid drainage port (body fluid drainage port corresponding area) and the area behind the body fluid drainage port corresponding area, facing the groove of the buttocks, are bulged. The absorbent material 4 has dimensions and shape that do not protrude from the top sheet 3 and the back sheet, and at the front and rear edges of the absorbent material, the outer edges of the back sheet and the top sheet 3 are joined by adhesive means such as hot melt adhesive, heat seal, or ultrasonic seal.

[0029] As shown in Figure 2, side sheets 7, 7 may be provided along the longitudinal direction D1 at both ends of the transverse direction D2 on the outer side of the absorbent 4. A water-repellent nonwoven fabric or a hydrophilic nonwoven fabric can be used as the side sheet 7.

[0030] In the examples shown in Figures 1 to 4, the absorbent article 1 is a so-called wingless type without wings, but it may also be configured as a winged article having wings extending to the sides. The wings may be formed by joining the side sheet and the back sheet.

[0031] Furthermore, the back sheet side of the absorbent article 1 (the side that does not come into contact with the skin, i.e., the side that faces the underwear when worn) may be provided with an adhesive portion to prevent the absorbent article 1 from shifting away from the underwear when attached to the underwear. The adhesive portion to prevent shifting may be formed in the shape of multiple strips extending in the vertical direction D1 or the horizontal direction D2.

[0032] The total length of absorbent article 1 can be 140 to 430 mm, and the width of absorbent article 1 (the width of the main body excluding the wings if it has wings) can be 40 to 130 mm.

[0033] (Packaging sheet) The materials that make up the packaging sheet 10 are not particularly limited, and paper, resin film, nonwoven fabric, etc., can be used.

[0034] The packaging sheet 10 containing paper has a low environmental impact when disposed of and is preferable from the standpoint of sustainable development goals. Furthermore, paper can impart a unique texture, such as the gentle appearance and feel of natural materials. In this specification, "paper" can refer to a flat sheet made by binding plant fibers or other fibers together with an adhesive. In particular, it can refer to paper primarily made from plant fibers (pulp), for example, paper in which plant fibers make up 50% or more of the fibers, preferably 80% or more. The type of pulp contained in the paper may include wood pulp, non-wood pulp, or recycled paper pulp, and these may be either mechanical pulp or chemical pulp. The pulp may be recycled pulp from absorbent articles and / or packaging sheets for absorbent articles. Additives may also be added to the paper. Furthermore, specific examples of paper used in the packaging sheet 10 include various types of paper such as Western paper, Japanese paper, processed paper, and synthetic paper. Furthermore, papers conventionally used for other purposes, such as newsprint, printing paper (including fine paper), writing paper, drawing paper, packaging paper, tissue paper, and miscellaneous paper, can be used either unprocessed or processed. When using tissue paper, thin imitation paper, Indian paper, rice paper, glassine paper, tissue paper, toilet paper, filter paper, etc., may also be used.

[0035] When a resin film is used as the material for the packaging sheet, even when printing is applied to the packaging sheet, the outlines of the printed characters and patterns become clearer, and the color development of the colorants is also improved, thus enhancing the design of the packaging sheet. Examples of resins that can be used include polyolefins such as polypropylene and polyethylene, polyester, and polyvinyl alcohol. Stretched resin films are preferred. Furthermore, the resin film may be either a non-permeable film or a permeable film.

[0036] When nonwoven fabric is used as the material for the packaging sheet 10, the texture, flexibility, etc., can be improved. Meltblown nonwoven fabric, spunbond nonwoven fabric, etc., are preferred as the nonwoven fabric used, and a combination of multiple layers of these nonwoven fabrics can also be used. Furthermore, the fibers constituting the nonwoven fabric may be polyolefins such as polypropylene and polyethylene, polyamides such as polyester and nylon, etc.

[0037] The packaging sheet 10 may be a single-layer sheet made of the above-mentioned materials, or it may be a laminated sheet made by laminating multiple layers made of different materials. For example, it may be a sheet made by laminating a resin film and paper.

[0038] The inner and / or outer surfaces of the packaging sheet 10 may be treated with a release agent. The release agent may be a liquid release agent (mold release agent) containing, for example, a silicone resin, paraffin resin, or fluororesin. For example, by treating the inner surface of the packaging sheet 10 with a release agent, the aforementioned adhesive portion for preventing slippage formed on the back of the absorbent article 1 can be brought into direct contact with the inner surface of the packaging sheet 10, thus eliminating the need to provide a separate release sheet between the absorbent article 1 and the packaging sheet 10.

[0039] The dimensions of the packaging sheet 10 depend on the size and shape of the absorbent article 1 to be packaged. For example, when the packaging sheet 10 is fully unfolded (not folded), the length in the vertical direction D1 (sometimes simply called the length) can be 100 to 450 mm, and the length in the horizontal direction D2 (sometimes simply called the width) can be 70 to 250 mm. In the illustrated example, the packaging sheet 10 has a rectangular shape when unfolded, but it may also have a shape such as an elongated ellipse.

[0040] (Packaging structure of individually packaged absorbent articles) In the individually packaged absorbent article 100, the absorbent article 1 is packaged by being folded together with the packaging sheet 10. When folding, as shown in Figure 2, the absorbent article 1 is placed on the inner surface of the packaging sheet 10 with the back sheet side of the absorbent article 1 facing the packaging sheet 10. Then, the packaging sheet 10 and the absorbent article 1 are folded together in the vertical direction D1 along the first fold line F1 and the second fold line F2 along the width direction D2. More specifically, at the first fold line F1, a first region R1 including one end 11 of the packaging sheet 10 in the vertical direction D1 is folded back in the vertical direction D1, and at the second fold line F2, a second region R2 including the other end 12 of the packaging sheet 10 in the vertical direction D1 is folded back. The region between the first region R1 and the second region R2 of the packaging sheet 10 is the third region R3. In the illustrated example, the packaging sheet 10 is folded so that the second region R2 is folded first, and the first region R1 overlaps the outer surface of the second region R2 (Figure 1), however, the folding order of the first region R1 and the second region R2 may be reversed. In this way, the packaging sheet 10 is folded into thirds (inner thirds) together with the absorbent article 1 to wrap the absorbent article 1, and then both edges in the horizontal direction D2 are sealed along the vertical direction D1 (Figure 1).

[0041] Such tri-fold or more packaging can be formed relatively easily, allows for hygienic wrapping of the absorbent article 1, and facilitates the removal of the absorbent article 1. The folding method is not limited to tri-folding; it can also be quad-folded or more (as explained later), or folded in half.

[0042] Furthermore, the individually packaged absorbent article 100 may have a fastening tape 50 in the center of the lateral direction D2 near the edge of the first region R1 (one end 11 of the packaging sheet 10). As shown in Figure 1, the fastening tape 50 may be provided across the first region R1 and the second region R2, straddling one end 11 of the packaging sheet 10. The presence of the fastening tape 50 makes it easier to open the individually packaged absorbent article 100, as the user can lift and pull the first region R1 by holding the fastening tape 50. At that time, the first region R1 is peeled away from the second region R2 located below it.

[0043] (Seal part) As shown in Figure 1, in the individually packaged absorbent article 100, the areas on both edges in the lateral direction D2 where the absorbent article 1 is not present are sealed, forming sealed portions 20, 20. In the first embodiment, the sealed portions 20, 20 may be formed along the entire length of the individually packaged absorbent article 100 in the vertical direction D1. This is preferable from the viewpoint of preventing dirt, dust, or accidentally entering from the lateral edges (achieving sealing performance). However, as shown in Figure 1, in this embodiment, the sealed portion 20 may have a main sealed portion 26 that forms the main part of the sealed portion, and a weak sealed portion 25 formed within a predetermined range in the vertical direction D1 from the first fold line F1. In the illustrated example, the main sealed portion 26 constitutes the portion other than the weak sealed portion 25. The weak sealed portions 25, 25 are portions with lower bonding strength than the main sealed portion 26. In this specification, the bonding strength of the weak seal portion 25 and the bonding strength of the main seal portion 26 refer to the peel strength when the packaging sheet 10 is peeled off in the vertical direction D1 when opening the individually packaged absorbent article 100.

[0044] As described above, when opening the individually packaged absorbent article 100, the user first holds the edge (one end 11) of the first region R1 near the center of the lateral direction D2, and possibly the fastening tape 50, and pulls up the first region R1. In the sealed portion 20, the user peels the first region R1 away from the second region R2, and then peels it away from the third region. In this case, there is a distance between the gripping position of the packaging sheet 10 (first region R1) and the position where the packaging sheets 10 separate from each other (separation position), and because the packaging sheet 10 is flexible, the force with which the user pulls the packaging sheet 10 does not easily reach the separation position. Therefore, with the normal opening method, even if the first region R1 is fully unfolded, the seal near the first fold line F1 is not completely released, meaning that the joint between the packaging sheets 10 in the sealed portion 20 tends to remain. In this specification, the portion of the sealed portion 20 where the seal remains is also called the seal residue. Furthermore, the same applies when unfolding the second region R2 after unfolding the first region R1, and seal residue may remain near the second fold line F2. If seal residue remains near fold lines F1 and F2, fold lines or creases will remain on the packaging sheet 10. More specifically, even if the packaging sheet 10 is spread flat, folds will immediately occur at fold lines F1 and F2, causing the packaging sheet 10 to fold again, or to be rolled inward, or wrinkles to form near fold lines F1 and F2.

[0045] In contrast, in this embodiment, weak seal portions 25, 25, ... with relatively low bonding strength are formed near the first fold line F1 and the second fold line F2, making it easier to peel off the packaging sheet 10 near the first fold line F1 and the second fold line F2, and reducing the amount of seal residue even when unfolding the packaging sheet 10 using a normal method (normal gripping position, normal force). As a result, the packaging sheet 10 can be kept flat, and when the packaging sheet 10 is used to wrap and dispose of used absorbent materials, curling inwards is suppressed, allowing for a smoother wrapping process.

[0046] In the example shown in Figure 1, weak seal portions 25, 25 are formed near both the first fold line F1 and the second fold line F2, respectively, which has the effect of reducing remaining seal in both the first fold line F1 and the second fold line F2. However, the weak seal portions 25 may be formed near either the first fold line F1 or the second fold line F2.

[0047] Furthermore, the weak seal portion 25 is formed in at least one of the following ranges: from the first fold line F1 (one end in the vertical direction D1 of the individually packaged absorbent article 100) to a predetermined length, and from the second fold line F2 (the other end in the vertical direction D1 of the individually packaged absorbent article 100) to a predetermined length (Figure 1). Here, the range in which the weak seal portion 25 is provided can be a range extending in the vertical direction D1 from the fold line (first fold line F1 or second fold line F2) for a length L5 (Figure 1). The range extending in the vertical direction D1 from the fold line (vertical length L5) is preferably 3 to 20 mm, more preferably 5 to 10 mm. By forming the weak seal portion 25 in the above range, the original function of the seal portion 20, namely preventing the intrusion of foreign matter and hygienically storing the absorbent article, can be maintained while improving the effect of reducing remaining seal near the fold lines F1 and F2. Furthermore, the weak seal portion 25 may be formed over the entire above range.

[0048] Figure 5 shows an enlarged view of part III, which includes one seal portion 20. As shown in Figure 4, the seal portion 20 may include a plurality of joint portions 30, 30, ... that are spaced apart from each other in a plan view. Each joint portion 30, 30, ... is a portion where the packaging sheets 10 are joined together in the thickness direction. In the illustrated example, the parts other than the plurality of joint portions 30, 30, ... are non-jointed portions where the packaging sheets 10 are not joined together. By having the joint portions 30, 30, ... spaced apart from each other in this way, it is possible to prevent the packaging sheet from becoming difficult to peel off when opened, which could lead to damage to the packaging sheet, or the edges from becoming excessively hard and impairing the feel, compared to, for example, a case where joint portions are formed across the entire surface of the seal portion 20.

[0049] The means for forming the joints 30, 30, ... are not particularly limited, and any means that the stacked packaging sheets 10 are pressed and / or heated to form a joint between the packaging sheets 10 can be used, such as heat sealing, ultrasonic sealing, or mechanical compression. These means can be appropriately selected and used depending on the material of the packaging sheets 10. For example, if the packaging sheets 10 are made of a material containing resin film and / or resin fibers, it is preferable to form the joint by partially fusing the packaging sheets 10 by heat sealing or ultrasonic sealing. If the packaging sheets 10 contain paper, it is preferable to form the joint by a mechanical joining method such as compression. In that case, the seal portion 20 can be formed using a pair of rolls, for example, one roll having a surface with an uneven pattern corresponding to the pattern of the joints 30, 30, ... and a counter roll with a surface without unevenness facing the said roll. Adhesives and the like can also be used instead of or in addition to any of the above joining methods.

[0050] The specific form of the weak seal portion 25 is not particularly limited, as long as the bonding strength of the weak seal portion 25 (peel strength when peeling the packaging sheet 10 in the longitudinal direction D1) is lower than the bonding strength of the main seal portion 26. In the example shown in Figure 5, the width (length in the transverse direction D2) of the weak seal portion 25 where the bonding portions 30, 30, ... are provided is smaller than the width of the main seal portion 26 where the bonding portions 30, 30, ... are provided. In other words, the inner end 25a in the transverse direction D2 of the bonding portion 30, 30, ... included in the weak seal portion 25 is closer to the edge in the transverse direction D2 of the packaging sheet 10 or the individually packaged absorbent article 100 than the inner end 26a in the transverse direction D2 of the bonding portion 30, 30, ... included in the main seal portion 26. Therefore, the force required to eliminate the weak seal portion 25 is smaller than the force required to eliminate the main seal portion 26, and the amount of seal residue can be reduced.

[0051] As mentioned above, if there is any remaining seal, a crease or fold remains, making it difficult to flatten the packaging sheet. However, the impact of the remaining seal on the crease or fold is greater the closer the remaining seal is to the center in the horizontal direction D2. In the example shown in Figure 5, the inner ends of the joints 30, 30, ... included in the weak seal portion 25 in the horizontal direction D2 (more specifically, the inner ends of the innermost joints) are positioned further outward in the horizontal direction D2 compared to the inner ends of the joints 30, 30, ... included in the main seal portion 26 in the horizontal direction D2. Therefore, even if the packaging sheet 10 is not fully unfolded in the vertical direction D1 when opened, and the weak seal portion 25 remains, a crease or fold remains less likely to occur due to the remaining seal.

[0052] Furthermore, at the lateral edge D2 of the individually packaged absorbent article 100, the number of overlapping packaging sheets 10 varies depending on the location (Figure 4). The more overlapping packaging sheets 10 there are, the stronger the bonding strength between the packaging sheets at the sealed area in that location, and the fewer overlapping sheets there are, the weaker the bonding strength. In this embodiment, the weak seal area 25 is formed in the region where two packaging sheets 10 are overlapped. Therefore, the bonding strength of the weak seal area 25 can be further reduced, making it easier to peel off the packaging sheet 10 at the weak seal area 25 when opening.

[0053] (Other examples of seals) Figure 6 shows a modified example of the seal portion 20. In the example shown in Figure 6, similar to the example shown in Figure 5, the inner ends in the lateral direction D2 of the joints 30, 30, ... included in the weak seal portion 25 are closer to the edge in the lateral direction D2 than the inner ends in the lateral direction D2 of the joints 30, 30, ... included in the main seal portion 26, so the same effect as described for the example in Figure 5 is obtained. Furthermore, in the example shown in Figure 6, the position of the joint 30 located furthest in the lateral direction D2 among the joints 30, 30, ... included in the weak seal portion 25 is such that, when viewed in the vertical direction D1, the closer it is to the fold lines F1 and F2, the closer it is to the edge in the lateral direction D2. As a result, when peeling off the packaging sheet 10, there is no abrupt change in the number of joints 30, 30, ... lined up in the lateral direction D2 at the boundary between the main seal portion 26 and the weak seal portion 25, and the transition from the main seal portion 26 to the weak seal portion 25 becomes smoother.

[0054] Furthermore, in this example, the inner contours of the joints 30, 30, ... in the weak seal portion 25 are arranged to be curved. Moreover, the curve of the inner contour becomes gentler as it approaches the end of the vertical direction D1 (fold line F1 or F2). This shape also improves the design of the weak seal portion 25.

[0055] Figures 7 and 8 also show other examples of the weak seal portion 25. In both examples shown in Figures 7 and 8, the weak seal portion 25 is formed by making the density of the joints 30, 30, ... in the weak seal portion 25 smaller than the density of the joints 30, 30, ... in the main seal portion 26. Therefore, in both Figures 7 and 8, the extent of the joints 30, 30, ... included in the weak seal portion 25 in the lateral direction D2 is approximately the same in width (length in the lateral direction D2) as the extent of the joints 30, 30, ... included in the main seal portion 26 in the lateral direction D2. This is preferable from the viewpoint of high sealing performance before opening, near the fold lines F1 and F2.

[0056] In the example shown in Figure 7, the area per joint 30, 30, ... in the weak seal portion 25 is smaller than the area per joint 30, 30, ... in the main seal portion 26. Furthermore, as shown in Figure 7, the area per joint 30, 30, ... in the weak seal portion 25 may decrease as it approaches the fold lines F1 and F2. This reduces the bonding strength as it approaches the fold lines F1 and F2, making it easier to peel off the packaging sheet 10 in the weak seal portion 25.

[0057] In the example shown in Figure 8, the pitch in the vertical direction D1 of the joints 30, 30, ... in the weak seal section 25 is made larger than the pitch in the vertical direction D1 of the joints 30, 30, ... in the main seal section 26, thereby reducing the density of the joints 30, 30, ... in the weak seal section 25 and lowering the joint strength. Alternatively, the spacing in the vertical direction D1 between the joints 30, 30, ... in the weak seal section 25 is made larger than the spacing in the vertical direction D1 between the joints 30, 30, ... in the main seal section 26. In Figure 8, the pitch in the vertical direction D1 of the joints 30, 30, ... or the spacing in the vertical direction D1 between the joints 30, 30, ... is constant within the weak seal section 25, but the pitch or spacing may be configured to increase as it approaches the fold line.

[0058] Furthermore, the plan view shape of each joint 30, 30, ... is not limited to circles as shown in Figures 5-8, but may also be elliptical, polygonal, such as square, rectangle, parallelogram, heart-shaped, star-shaped, teardrop-shaped, etc. Also, the circular equivalent diameter (diameter of a true circle with the same area) of each joint 30 in the entire sealing portion 20 may be 0.5 to 2.5 mm.

[0059] <Second Embodiment> Figure 9 shows an individually packaged absorbent article 200 according to a second embodiment of the present invention. The basic structure of the individually packaged absorbent article 200 is the same as that of the individually packaged absorbent article 100 according to the first embodiment, but the individually packaged absorbent article 200 differs from the individually packaged absorbent article 100 in that the structure of the sealing portion 20 is different. In the individually packaged absorbent article 200, an unsealed portion 27 is provided instead of the weakly sealed portion 25 in the individually packaged absorbent article 100. In other words, the sealing portion 20 does not extend to the fold line F1 and / or does not extend to the fold line F2.

[0060] The area in which the non-seal portion 27 is formed may be the same as the area in which the weak seal portion 25 is formed. Therefore, the area in which the non-seal portion 27 is provided can be an area extending in the vertical direction D1 for a length L7 from the fold line (first fold line F1 or second fold line F2) (Figure 9), and such an extension in the vertical direction D1 from the fold line (vertical length L5) may be preferably 3 to 20 mm, more preferably 5 to 10 mm. Furthermore, the area in which the non-seal portion 27 is formed may be different from the area in which the weak seal portion 25 is formed. Note that since the non-seal portion 27 is more effective in suppressing seal residue than the weak seal portion 25, the area from the fold line in which the non-seal portion 27 is formed may be smaller than the area from the fold line in which the weak seal portion 25 is formed.

[0061] In these non-sealed sections 27, the packaging sheets 10 are not joined together, so the aforementioned seal residue does not occur in the non-sealed sections 27. Therefore, peeling off the packaging sheets 10 near the first fold line F1 and the second fold line F2 is easy, and when the packaging sheets 10 are unfolded using a normal method (normal gripping position, normal force), seal residue can be eliminated. As a result, the packaging sheets 10 can be kept flat, so the absorbent article 1 can also be unfolded flat, making it easier to remove the absorbent article 1 when attaching it. Furthermore, when the packaging sheets 10 are used to wrap and dispose of used absorbent articles, curling inwards on the inner side of the packaging sheets is suppressed, allowing for a smoother wrapping process.

[0062] Furthermore, the non-seal portion 27 can also function as an air vent from the inside to the outside of the individually packaged absorbent article 200 during manufacturing. For example, if a sudden and large force is applied to the individually packaged absorbent article 200 from the outside during manufacturing or when it is placed in the package, compressed air may press against the seal portion, causing damage to the seal portion (and the packaging of the individually packaged absorbent article to burst). Such problems can be avoided by properly releasing the air to the outside in the lateral direction D2 through the non-seal portion 27.

[0063] Above, we have described a first embodiment having a weak seal portion 25 and a second embodiment having a non-seal portion as specific forms, but the features included in both can be combined with each other. For example, the individually packaged absorbent article 100 shown in Figure 1 has four weak seal portions 25 formed therein, but one to three of these may be replaced with non-seal portions 27. Alternatively, an unsealed portion may be formed within one of the weak seal portions 25. For example, the portion of at least one weak seal portion 25 of the individually packaged absorbent article 100 shown in Figure 1 from the middle of the vertical direction D1 to the fold line may be replaced with a non-seal portion 27.

[0064] <Third Embodiment> Figure 10 shows an individually packaged absorbent article 300 according to a third embodiment of the present invention. Figure 11 shows a cross-section along line IV-IV of Figure 10, and Figure 12 shows a cross-section along line VV of Figure 1. Note that the absorbent article 1 contained within is not shown in Figure 10.

[0065] The basic structure of the individually packaged absorbent article 300 according to the third embodiment is the same as that of the individually packaged absorbent article 100 according to the first embodiment. The sealing portion 20 is also similar in that it is equipped with a weak sealing portion 25 at a predetermined location. However, while the individually packaged absorbent article 100 according to the first embodiment was a tri-fold packaging form, the individually packaged absorbent article 300 according to the third embodiment is a quad-fold packaging form. In the case of a quad-fold as in this embodiment, the packaging sheet 10 is folded back along the third fold line, which is located along the lateral direction D2 between the second fold line F2 and the other end 12, before folding back the second region R2 along the second fold line F2. Such a form with many folds is suitable when the total length of the absorbent article 1 is long, or when it is desired to individually package the absorbent article 1 as compactly as possible.

[0066] In this embodiment, as shown in Figure 12, the seal portion 20 is formed with a portion where two, three, and four sheets of the packaging sheet 10 are overlapped. In this embodiment as well, as described in the first embodiment, it is preferable that the weak seal portion 25 of the packaging sheet 10 is formed in the portion where two sheets of the packaging sheet 10 are overlapped. This further reduces the bonding strength of the weak seal portion 25, making it easier for the packaging sheet 10 to peel off at the weak seal portion 25 when opened, thereby improving the effect of reducing seal residue when opened.

[0067] Although the present invention has been described above based on embodiments, the present invention is not limited to these embodiments. The above embodiments can be modified, altered, replaced, added, deleted, and combined in various ways within the scope of the claims, and these also fall within the technical scope of the present invention. Furthermore, the above-mentioned components can be combined in any way. [Explanation of Symbols]

[0068] 1. Absorbent articles 3 Top Sheet 4 Absorbent 7 Side Seats 10 Packaging Sheets 11 One end in the vertical direction 12 The other end in the vertical direction 20 Seal part 25 Weak seal area 26 Main sealing section 27 Non-sealed portion 30 Joint 50 Fastening Tapes 100, 200, 300 individually packaged absorbent articles D1 Longitudinal direction of the packaging sheet D2 Transverse direction of the packaging sheet F1 First fold line F2 Second fold line F3 Third fold line R1 1st area R2 2nd area R3 3rd area

Claims

1. An individually packaged absorbent article comprising a packaging sheet and an absorbent article individually packaged by the packaging sheet, The packaging sheet has a vertical direction and a horizontal direction perpendicular to the vertical direction, The packaging sheet is folded in the vertical direction along first and second fold lines and horizontal directions, and the horizontal edges each have a region where three or four of the packaging sheets are stacked and a region where two of the packaging sheets are stacked, and a seal portion is formed on each of the edges. In the sealing portion, a weak sealing portion is provided in at least one of the vertical range from the first fold line to 20 mm and the vertical range from the second fold line to 20 mm, where the bonding strength is lower than that of the main sealing portion, which is the rest of the sealing portion. The sealing portion includes a plurality of joints that are spaced apart from each other, The main sealing portion is provided across the area where three or four of the packaging sheets are stacked and the area where two of the packaging sheets are stacked. Individually packaged absorbent article, wherein the inner lateral end of the joint included in the weak seal portion is located further outward in the lateral direction of the packaging sheet as it approaches the more proximal fold line of the first fold line and the second fold line when viewed in the vertical direction.

2. An individually packaged absorbent article comprising a packaging sheet and an absorbent article individually packaged by the packaging sheet, The packaging sheet has a vertical direction and a horizontal direction perpendicular to the vertical direction, The packaging sheet is folded in the vertical direction along a first fold line and a second fold line along the horizontal direction, and the horizontal edge has a region where three or four of the packaging sheets are stacked and a region where two of the packaging sheets are stacked, A sealing portion is formed on each of the aforementioned edges by heat sealing or ultrasonic sealing. An unsealed portion is provided in at least one of the vertical ranges from the first fold line to 20 mm and from the second fold line to 20 mm. Individually packaged absorbent article, wherein the sealing portion is provided across the area where three or four of the packaging sheets are stacked and the area where two of the packaging sheets are stacked.

3. The individually packaged absorbent article according to Claim 1, wherein the lateral inner end of the joint included in the weak seal portion is closer to the lateral edge of the packaging sheet than the lateral end of the main seal portion.

4. The individually packaged absorbent article according to Claim 1, wherein the density of the joint in the weak seal portion is less than the density of the joint in the main seal portion.

5. The individually packaged absorbent article according to claim 1, wherein the weak seal portion is formed in the region where two packaging sheets are stacked.

6. The joint portion of the weak seal portion is arranged such that the inner contour of the weak seal portion is curved, as in the individually packaged absorbent article according to claim 1.

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