Absorbent article
The absorbent article's design with a bonding means and cover member addresses the issue of reduced joining strength by minimizing foreign matter adherence, ensuring effective closure and hygienic disposal.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- UNI CHARM CORP
- Filing Date
- 2025-12-16
- Publication Date
- 2026-07-02
AI Technical Summary
Existing absorbent articles with closing mechanisms face a decrease in joining strength due to adherence of foreign substances like sebum and dust, making it difficult to maintain a closed state during disposal.
The absorbent article features a bonding means on the skin side with an overlapping region in the longitudinal direction, where the skin-side portion of the bonding means is located on the non-skin side in the thickness direction, and is covered by a cover member such as a top sheet, reducing the likelihood of foreign matter adherence and maintaining bonding strength.
This design suppresses the decrease in bonding strength, allowing for easier and hygienic disposal by ensuring the closing mechanism remains effective despite exposure to foreign substances.
Smart Images

Figure JP2025043873_02072026_PF_FP_ABST
Abstract
Description
Absorbent article
[0001] The present invention relates to an absorbent article.
[0002] Patent Document 1 describes an absorbent article that is easy to remove after use and can maintain a small and bundled state after removal. Specifically, when the used absorbent article is rolled up from one end in the longitudinal direction for disposal, it is said that it can be held in a rolled-up state by a belt-like region near the outer peripheral edge of the absorbent article.
[0003] Japanese Patent Application Laid-Open No. 2024-77999
[0004] On the other hand, when the absorbent article absorbs a large amount of excrement, the swelling in the thickness direction increases, so it may be difficult to roll it up from the end. In that case, an absorbent article provided with a closing mechanism that closes in a state of being folded with the skin surface side inside is desired. The closing mechanism is provided such that, for example, when the absorbent article is folded in half with the skin surface side inside, joining means such as an adhesive or a self-adhesive faces the both ends of the absorbent article. In an absorbent article provided with such a closing mechanism, after use, by closing the skin side surface to which excretory fluid has adhered, it can be hygienically discarded in a state where the excretory fluid and its odor are contained.
[0005] However, when foreign substances such as sebum, fiber dust, and dust adhere to the surface of the closing mechanism (joining means such as a self-adhesive) during use (when worn) of the absorbent article, the joining strength of the self-adhesive or the like may decrease. In this case, when discarding the absorbent article, there is a risk that it will be difficult to maintain the closed state.
[0006] The present invention has been made in view of the above problems, and an object thereof is to suppress a decrease in the joining strength of the closing mechanism in an absorbent article provided with the closing mechanism.
[0007] The main invention for achieving the above objective is an absorbent article having a liquid-absorbing absorbent core, having longitudinal, width, and thickness directions that are mutually orthogonal in an unfolded state, having a bonding means on the skin side that can be bonded to a part of the absorbent article when discarded, having an overlapping region in the longitudinal direction that overlaps with the bonding means in an unfolded and extended state, and the skin side of the bonding means having a portion that is located on the non-skin side than the portion of the overlapping region that is located on the skin side in the thickness direction.
[0008] Other features of the present invention will be made clearer by description in this specification and the accompanying drawings.
[0009] According to the present invention, in an absorbent article equipped with a closing mechanism, it is possible to suppress a decrease in the bonding strength of the closing mechanism.
[0010] This is a schematic plan view of the pad 1 in its unfolded and extended state, as seen from the skin side. This is a schematic cross-sectional view of the pad 1. Figures 3A and 3B show the state when the pad 1 is folded in half in the longitudinal direction. These are partially enlarged views to explain the details of the structure of the pad 1. Figures 5A and 5B are explanatory diagrams of the one-sided joining means 30 and the other-sided joining means 30'. These are diagrams to explain the joining means 30 and 30'. This is a diagram explaining the through hole 2h of the top sheet 2. This is a cross-sectional view explaining the arrangement of the joining means 30, 30' and the absorbent core 10. This is a plan view showing a modified cover member. Figures 10A and 10B are cross-sectional views taken along the line C-C in Figure 9. These are plan views explaining the joining means 30 and cover portion 50 of the urine absorption pad 1 of the second embodiment. Figures 12A and 12B are cross-sectional views taken along the line Y-Y in Figure 11. Figures 13A and 13B are diagrams explaining an example in the urine absorption pad 1 of the second embodiment where the cover portion 50 is not provided. Figures 14A and 14B illustrate another example of the urine absorption pad 1 of the second embodiment in which the cover portion 50 is not provided. This is a cross-sectional view illustrating the configuration of the joining means 30, 30' and the top sheet 2. This is a diagram illustrating the operation and effect of the pad 1 to which the joining means 30, 30' are applied. This is an explanatory diagram showing a modified example of the joining means 30, 30' of the pad 1.
[0011] The following matters will become clear from the description in this specification and the accompanying drawings: (Aspect 1) An absorbent article having a liquid-absorbing absorbent core having longitudinal, width and thickness directions that are mutually orthogonal in an unfolded state, wherein the skin-facing side has a bonding means that can be bonded to a part of the absorbent article when discarded, and in an unfolded and extended state, has an overlapping region that overlaps with the bonding means in the longitudinal direction, and the skin-facing side of the bonding means has a portion that is located on the non-skin side than the portion of the overlapping region that is located on the skin side in the thickness direction.
[0012] According to the absorbent article of Embodiment 1, when worn, the probability of foreign matter such as sebum and lint adhering to at least a portion (lower part) of the skin-facing side of the fastening means (closing mechanism) is lower compared to the position closest to the skin in the overlapping area. Therefore, a decrease in the bonding force at the skin-facing side (lower part) of the fastening means is suppressed. This makes it easier to fasten the skin-facing side (lower part) of the fastening means to a portion of the absorbent article, and when the absorbent article is disposed of, it can be disposed of hygienically with the skin-facing side to which excrement has adhered closed.
[0013] (Aspect 2) The absorbent article according to aspect 1, wherein the portion of the skin-facing side of the joining means that is located on the non-skin side than the portion located on the skin side straddles the central position of the absorbent article in the width direction.
[0014] According to the absorbent article of embodiment 2, a lower portion is formed in the center of the width direction of the joining means, making it difficult for foreign matter to adhere to it. As a result, the decrease in joining force in the center of the joining means is suppressed, and the operation of pressing the joining means against opposing surfaces becomes easier.
[0015] (Aspect 3) The absorbent article according to aspect 1 or 2, wherein, when viewed in the thickness direction, it has a cover member that covers at least a portion of the joining means from the skin side.
[0016] According to the absorbent article of embodiment 3, by providing a cover member having a predetermined thickness, a step is more easily formed in the thickness direction between the skin surface of the cover member and the skin surface (lower part) of the joining means, thereby reducing the probability of foreign matter such as sebum and lint adhering to the skin surface (lower part) of the joining means. Furthermore, foreign matter is less likely to adhere to the portion of the joining means covered by the cover member, and the bonding force is less likely to decrease. Therefore, it is possible to suppress a decrease in the bonding force of the joining means (closing mechanism).
[0017] (Aspect 4) The absorbent article according to any one of aspects 1 to 3, wherein the cover member is a top sheet provided on the skin side of the absorbent core, and the joining means is arranged between the absorbent core and the top sheet in the thickness direction.
[0018] According to the absorbent article of embodiment 4, the top sheet functions as a cover member that covers the skin side of the bonding means, so there is no need to separately provide other sheet members as cover members. Therefore, it is possible to suppress increases in material costs and manufacturing costs. In addition, when wearing the absorbent article, there is no extra cover member interposed between the wearer's skin and the top sheet, so the feel and fit are less likely to deteriorate, and the user is less likely to experience discomfort.
[0019] (Aspect 5) The absorbent article according to any one of aspects 1 to 4, wherein the top sheet has an opening that penetrates in the thickness direction in the overlapping region.
[0020] In the absorbent article of embodiment 5, a height difference is formed between the portion of the top sheet where through holes (openings) are formed and the portion where they are not, based on the thickness of the top sheet. Then, the portion of the skin side of the joining means that overlaps with the through holes becomes a lower portion located on the non-skin side in the thickness direction, making it difficult for foreign matter to adhere to it. As a result, it becomes easier to maintain the bonding force of the joining means in the portion that overlaps with the through holes.
[0021] (Aspect 6) The absorbent article according to any one of aspects 1 to 5, wherein the top sheet has a break guide line in the overlapping region for breaking the top sheet.
[0022] According to the absorbent article of embodiment 6, the skin-facing side of the bonding means is covered by the top sheet, which suppresses a decrease in the bonding strength of the bonding means when the absorbent article is worn. Furthermore, when the absorbent article is disposed of, a portion of the top sheet can be cut and removed along the break guide line, making it possible to widely expose the skin-facing side of the bonding means where the bonding strength has not decreased. This makes it easier to firmly press the bonding means against the opposing surface.
[0023] (Aspect 7) The absorbent article according to any one of aspects 1 to 6, wherein, when viewed in the thickness direction, the entire joining means is covered by the cover member.
[0024] According to the absorbent article of Embodiment 7, foreign matter is less likely to adhere to the portion of the joining means covered by the cover member, thus making it easier to suppress the decrease in joining force. Therefore, by having the entire joining means covered by the cover member, the decrease in joining force can be suppressed for the entire joining means. This makes it easier to press the joining means more strongly against opposing surfaces. (Embodiment 8) The absorbent article according to any one of Embodiments 1 to 7, wherein, when viewed in the thickness direction, at least a portion of the joining means is not covered by the cover member.
[0025] (Aspect 9) The absorbent article according to aspect 8, in which case at least a part of the joining means is exposed to the skin side in advance, the joining means can be joined using the part exposed to the skin side. With such a configuration, the joining means can be joined without removing the cover member covering the joining means, so the operation of pressing the joining means against opposing surfaces can be easily performed.
[0026] According to the absorbent article of Embodiment 9, compared to the joining means with a smaller proportion of the area covered by the cover member, the joining means with a larger proportion of the area covered by the cover member has a lower probability of foreign matter adhering to it, and the joining force is less likely to decrease. In other words, the joining force is more easily maintained in at least one of the one-sided joining means and the other-sided joining means, making it easier to press them together when facing each other. (Embodiment 10) The absorbent article according to any one of Embodiments 1 to 9, wherein the joining means comprises a one-sided joining means provided on one side in the longitudinal direction and a other-sided joining means provided on the other side in the longitudinal direction, and the one-sided joining means and the other-sided joining means are covered by a common cover member.
[0027] According to the absorbent article of embodiment 10, both the one-side joining means and the other-side joining means can be covered by a single cover member (e.g., a top sheet), thus eliminating the need for extra cover members (sheet members different from the top sheet). This simplifies the overall structure of the absorbent article, and since no extra sheet members are provided on the skin-facing side that comes into contact with the wearer's skin, manufacturing costs can be reduced while minimizing discomfort to the wearer. (Embodiment 11) The absorbent article according to any one of embodiments 1 to 10, wherein the joining means comprises a one-side joining means provided on one side in the longitudinal direction and a other-side joining means provided on the other side in the longitudinal direction, the one-side joining means having a portion covered by the cover member, and the other-side joining means not having a portion covered by the cover member.
[0028] According to the absorbent article of Embodiment 11, the joining means covered by the cover member (one-side joining means) has a lower probability of foreign matter adhering to it compared to the joining means not covered by the cover member (the other-side joining means), and the joining force is easier to maintain. Therefore, even if the joining force of the other-side joining means decreases, it is possible to press it together with the one-side joining means. In addition, since there is no need to provide a cover portion for the other-side joining means, the manufacturing cost of the absorbent article can be reduced. (Embodiment 12) The absorbent article according to any one of Embodiments 1 to 11, wherein in at least one of the longitudinal direction and the width direction, the joining means is arranged to straddle the end of the absorbent core.
[0029] According to the absorbent article of embodiment 12, a step is created in the thickness direction at the edge of the absorbent core, and steps (concave and convex regions) are more likely to be formed in the joining means arranged across the edge of the absorbent core. Therefore, foreign matter is less likely to adhere to the concave region of the joining means compared to the convex region, and the bonding force is less likely to decrease, making it easier to press the two together. (Embodiment 13) The absorbent article according to any one of embodiments 1 to 12, wherein the absorbent core has a pair of side sheets at both ends in the width direction, and the joining means has a portion that overlaps with the side sheets when viewed in the thickness direction and is located on the skin side in the thickness direction compared to the side sheets.
[0030] According to the absorbent article of embodiment 13, when worn, the portion of the bonding means that does not overlap with the side sheet is less likely to attract foreign matter and less likely to reduce bonding strength compared to the portion of the bonding means that is laminated on the skin side of the side sheet. Therefore, the portion that does not overlap with the side sheet is easier to press against the opposing surface. (Embodiment 14) The absorbent article according to any one of embodiments 1 to 13, wherein the absorbent core has a pair of side sheets at both ends in the width direction, and the bonding means has a portion that overlaps with the side sheet when viewed in the thickness direction and is located on the non-skin side in the thickness direction of the side sheet.
[0031] According to the absorbent article of embodiment 14, since the skin-facing side of the bonding means is located on the non-skin side than the skin-facing side of the side sheet, when worn, foreign matter is less likely to adhere to the skin-facing side of the bonding means compared to the skin-facing side of the side sheet, and the bonding force is less likely to decrease. Therefore, in the portion that does not overlap with the side sheet, it becomes easier to press the bonding means against the opposing surface. (Embodiment 15) The absorbent article according to any one of embodiments 1 to 14, wherein the surface of the bonding means has a plurality of convex portions that are convex in the thickness direction and concave portions that are concave in the thickness direction, and in the overlapping region, the convex portions are located on the skin side in the thickness direction.
[0032] According to the absorbent article of embodiment 15, when worn, the probability of sebum, lint, etc. adhering to the recessed parts of the bonding means is lower compared to the convex parts. Therefore, the bonding strength is less likely to decrease in multiple recessed parts on the skin-facing side of the bonding means. This makes it easier to press the bonding means against opposing surfaces.
[0033] ===First Embodiment=== As an example of the absorbent article according to the first embodiment, a urine pad (hereinafter sometimes simply referred to as "pad") will be used for explanation. However, the absorbent article according to this embodiment is not limited to a urine pad, and can also be applied to, for example, sanitary napkins, disposable panty-type diapers, shorts-type sanitary napkins, disposable tape-type diapers, pet diapers, absorbent sheets for nursing care or for pets, etc.
[0034] <Basic Structure of the Urine Absorption Pad 1> First, the basic structure of the urine absorption pad 1 will be explained. Figure 1 is a schematic plan view of the pad 1 in its unfolded and extended state, as seen from the skin side. Figure 2 is a schematic cross-sectional view of the pad 1. The urine absorption pad 1 can be used by placing it inside a pant-type or tape-type disposable diaper, or it can be used as a standalone pad by placing it directly inside the wearer's underwear (pants or shorts).
[0035] When unfolded, pad 1 has a roughly rectangular shape in plan view and has mutually perpendicular longitudinal, width, and thickness directions. The longitudinal direction follows the front-to-back direction from the wearer's abdomen to the back when pad 1 is worn. In the thickness direction, the side that contacts the wearer's skin is called the skin side, and the opposite side is called the non-skin side. Since pad 1 in this embodiment has a symmetrical configuration in the longitudinal direction, either side of pad 1 in the longitudinal direction may correspond to the wearer's abdomen. Also, unlike tape-type or pant-type diapers, pad 1 is worn without one end and the other end in the longitudinal direction being connected along the wearer's waist.
[0036] The unfolded state of pad 1 refers to the state in which the entire pad 1 is unfolded in a planar manner. The extended state of pad 1 refers to the state in which pad 1 is extended to the point in which wrinkles that were present on pad 1 are virtually invisible, and pad 1 is extended until the dimensions of each component constituting pad 1 (for example, the side sheet 4 described later) match or are close to the dimensions of the individual component.
[0037] The pad 1 comprises a liquid-absorbing core 10, a liquid-permeable surface sheet 2 (hereinafter sometimes referred to as "top sheet 2") (e.g., nonwoven fabric) provided on the skin side of the absorbent core 10, a liquid-impermeable back sheet 3 (e.g., a resin film such as polyethylene or polypropylene) provided on the non-skin side of the absorbent core 10, and a pair of side sheets 4 provided on both sides of the pad 1 in the width direction. As shown in Figure 2, the pair of side sheets 4 are folded inward in the width direction from the width direction side of the non-skin side of the back sheet 3 toward the skin side of the top sheet 2 so as to wrap around the absorbent core 10. In addition, a bonding means 30 (30'), which will be described later, is provided between the top sheet 2 and the absorbent core 10 in the thickness direction.
[0038] An example of the absorbent core 10 is a liquid-absorbing fiber, such as pulp fiber containing SAP (superabsorbent polymer), molded into a predetermined shape. The absorbent core 10 is covered with a liquid-permeable core wrap sheet 11 (e.g., tissue). However, the absorbent core 10 is not limited to the above, and may be an SAP sheet in which an SAP layer is attached to a hydrophilic sheet, or an airlaid sheet in which liquid-absorbing fibers are molded into a sheet by the airlaid method, or it may be a configuration of two or more layers. Furthermore, the absorbent core 10 does not have to be covered with the core wrap sheet 11.
[0039] Furthermore, a fixing member 20 is provided on the non-skin side of the pad 1 for attaching the pad 1 to the inner surface of a pant-type diaper or underwear (outer garment). Fixing members 20 are provided at both ends in the longitudinal direction of the pad 1. The fixing member 20 is, for example, a rectangular member, and its long side is provided so as to be aligned with the width direction of the pad 1. The fixing member 20 is preferably a member that can be peeled off from the inner surface of the outer garment without damaging the outer garment and can be reattached. In this embodiment, the fixing member 20 is a tape with a hook material (for example, the male part of a hook-and-loop fastener). Other examples of fixing members 20 include tape coated with adhesive. Note that the fixing member 20 may not be provided.
[0040] Furthermore, the pad 1 has a pair of leg-circumference elastic members 5 provided along the longitudinal direction on both sides in the width direction. In Figure 2, the leg-circumference elastic members 5 are fixed in an extended state in the longitudinal direction between the back sheet 3 and the side sheet 4. This makes it easier for both sides of the pad 1 in the width direction to conform closely to the wearer's legs.
[0041] Furthermore, the pad 1 has a pair of leak-proof wall portions 6 on both sides in the width direction that can be raised toward the skin. The leak-proof wall portion 6 comprises a side sheet 4 and a leak-proof wall elastic member 7. Both ends in the longitudinal direction are fixed to the surface sheet 2 by adhesive areas 8. The leak-proof wall elastic member 7 is fixed to the inner end of the side sheet 4 in the width direction in an extended state along the longitudinal direction of the pad 1. When the pad 1 is worn, the tip of the leak-proof wall portion 6 rises toward the skin based on the elasticity of the leak-proof wall elastic member 7, and the lateral leakage of excretory fluids, etc. is suppressed by the raised leak-proof wall portion 6.
[0042] Furthermore, the pad 1 has joining means 30, 30' at both ends in the longitudinal direction. The details of their configuration will be described below.
[0043] <Joining means 30, 30'>As shown in FIG. 1, one-side joining means 30 as a closing mechanism is provided at one end in the longitudinal direction. In the present embodiment, the one-side joining means 30 is provided adjacent to the non-skin side surface of the top sheet 2. That is, the top sheet 2 functions as a cover member that covers at least a part of the one-side joining means 30 from the skin side in the thickness direction. Similarly, on the other end in the longitudinal direction, the other-side joining means 30' is provided adjacent to the non-skin side surface of the top sheet 2. And when the pad 1 is discarded, the one-side joining means 30 as a closing mechanism can be joined to the other-side joining means 30' as a part of the pad 1. Note that the joining means 30, 30' of the present embodiment is a region where an adhesive (such as a self-adhesive adhesive described later) is provided at least in part.
[0044] FIG. 3 shows the state when the pad 1 is folded in two in the longitudinal direction. The state of being folded in two specifically means that the center line (central position) CL of the pad 1 in the longitudinal direction, that is, the pad 1 is bisected in the longitudinal direction and bent along the center line CL (hereinafter sometimes referred to as the fold line FL) along the width direction. This state is, for example, the state before use of the pad 1 or the state at the time of disposal after use. FIG. 3A is a plan view of the pad 1 in the state of being folded in two in the longitudinal direction, and FIG. 3B is a schematic cross-sectional view when the pad 1 is folded in two and the ends of the pad are closed and viewed from the width direction of the pad 1. As shown in FIGS. 3A and 3B, when the pad 1 is folded in two in the longitudinal direction, the one-side joining means 30 and the other-side joining means 30' are opposed and overlapped in the thickness direction and are arranged so as to be joined.
[0045] In the pad 1 of the present embodiment, when the one-side joining means 30 and the other-side joining means 30' are opposed to each other and joined as shown in FIG. 3B, among the one-side joining means 30 and the other-side joining means 30', the parts not covered by the top sheet 2 (such as the lower part 30s described later) are used to crimp the two. The parts of the joining means 30, 30' not covered by the top sheet 2 will be described later.
[0046] Figure 4 is a partial enlarged view for explaining the configuration details of the pad 1, and shows a part of the pad 1 in the deployed and extended state. Note that the position of the one-sided joining means 30 in the longitudinal direction will be described. Since the pad 1 is symmetric in the longitudinal direction, the configuration of the other-sided joining means 30' is the same as that of the one-sided joining means 30. The one-sided joining means 30 is provided at the end of the pad 1 in the longitudinal direction and at a position separated from the end of the pad 1 in the longitudinal direction by a predetermined distance d. A region that extends in the width direction at the predetermined distance d from the end of the pad 1 in the longitudinal direction to the one-sided joining means 30 is also called a dry edge D. The dry edge D is a non-adhesive region where no adhesive is provided from the end of the pad 1 to the one-sided joining means 30.
[0047] The one-sided joining means 30 and the other-sided joining means 30' have an adhesive 31 (hereinafter sometimes referred to as a self-adhesive or a self-adhesive adhesive) having self-adhesiveness as a joining portion. Note that the adhesive in this embodiment is not limited to a self-adhesive, and may be an adhesive.
[0048] Figures 5A and 5B are explanatory views of the one-sided joining means 30 and the other-sided joining means 30'. In Figures 5A and 5B, in order to explain the property (self-adhesiveness) when the joining means 30, 30' are brought into contact with each other, the top sheet 2 provided on the skin side of the joining means 30, 30' in the pad 1 is omitted and shown. The adhesive 31 as the joining portion provided on the one-sided joining means 30 and the other-sided joining means 30' has a property that its own tackiness (adhesiveness) is low, but when the adhesives 31 are crimped with a relatively weak pressure, an adhesive force (hereinafter referred to as a joining force) is developed. As shown in Figure 5A, when the one-sided joining means 30 and the other-sided joining means 30' are crimped, the one-sided joining means 30 and the other-sided joining means 30' adhere to each other by their respective adhesives 31 (the joining force is developed). On the other hand, as shown in Figure 5B, when the adhesive 31 abuts on a member other than the adhesive 31 such as a non-woven fabric provided on the pad 1 or the skin, it is difficult for the one-sided joining means 30 and the abutting member to adhere.
[0049] The bonding force between the adhesive 31 and the other members is preferably 1 / 4 or less of the bonding force between the adhesive 31s themselves. More preferably, the bonding force between the adhesive 31 and the other members is 1 / 10 or less of the bonding force between the adhesive 31s themselves. Furthermore, when the adhesive 31s are brought into contact with each other, they can be separated without damaging the adhesive 31s, and can be re-bonded by bringing them into contact again after separation.
[0050] The adhesive 31 is not particularly limited as long as it is safe to come into contact with the wearer's skin, and examples include emulsion-type self-adhesives (emulsion inks) and hot-melt self-adhesives (HMAs). As the main component of the emulsion-type self-adhesive, it can be used by mixing natural rubber, synthetic rubber, etc. with emulsifiers, etc., and those disclosed in Japanese Patent No. 2589307 and Japanese Patent Application Publication No. 2005-095381 may be used. As the main component of the hot-melt self-adhesive, it can be used by heating and melting thermoplastic resins such as polyolefin-based and polyamide-based resins, for example, as disclosed in Japanese Patent No. 7476348 and Japanese Patent No. 7543716. In this embodiment, an emulsion-type self-adhesive is used.
[0051] Next, the specific configurations of the one-sided joining means 30 and the other-sided joining means 30' will be explained in detail using Figure 6. Figure 6 is a diagram for explaining the joining means 30 and 30'. As shown in Figure 6, the one-sided joining means 30 and the other-sided joining means 30' are quadrilateral regions that circumscribe the portion to which the self-adhesive adhesive 31 is applied as the joining portion. In Figure 6, the region to which the self-adhesive adhesive 31 is applied is shown as a lightly filled area.
[0052] As mentioned above, in this embodiment, an emulsion-based self-adhesive agent is used as the bonding agent 31. Furthermore, one application is defined as applying the bonding agent 31 uniformly in a roughly rectangular shape that is long in the width direction (so-called solid coating), and in the example shown in Figure 6, it is applied repeatedly three times. By applying the bonding agent 31 in multiple layers in the thickness direction, the bonding strength when bonding agents 31 are joined together can be increased compared to the case of a single application. Note that although three applications are used in this embodiment, it is not limited to this.
[0053] In this embodiment, as shown in Figure 6, the application positions of the adhesive 31 are offset in the longitudinal and width directions. Therefore, as shown in the thickness direction diagrams (lower side view and right side view) of Figure 6, the amount of adhesive 31 applied per unit area (basis weight or basis weight) in the first adjacent regions L1 and W1 adjacent to one of the central regions Lc and Wc, and in the second adjacent regions L2 and W2 adjacent to the other, is less than the amount of adhesive 31 applied per unit area in the central regions Lc and Wc. In other words, since the amount of adhesive 31 applied per unit area is less than in the central regions Lc and Wc, the bonding strength is also lower than in the central regions Lc and Wc.
[0054] <About the cover member> In the pad 1 of this embodiment, as shown in Figures 1 and 4, a plurality of through holes 2h that penetrate the top sheet 2 (surface sheet) in the thickness direction are provided in a part of the area that overlaps with the joining means 30, 30' in a plan view. For example, when the area that overlaps with the joining means 30 (30') in the longitudinal direction is called the overlapping area OR (the area shown by the shaded part in Figure 4), a plurality of through holes 2h are scattered in the overlapping area OR. Note that the shape, arrangement, and number of through holes 2h are not limited to the example shown in Figure 4 and can be changed as appropriate.
[0055] Figure 7 illustrates the through-hole 2h of the top sheet 2. Figure 7A is a plan view showing an enlarged portion of the overlapping region OR, and Figure 7B is a schematic cross-sectional view showing the view along the line B-B in Figure 7A. As described above, in the pad 1 of this embodiment, the top sheet 2 is provided so as to cover the joining means 30 (30') from the skin side in the thickness direction. On the other hand, since the top sheet 2 is provided with a through-hole 2h, the portion of the joining means 30 that overlaps with the through-hole 2h is not covered by the top sheet 2. That is, as shown in Figure 7B, an opening is formed in the top sheet 2 by the through-hole 2h, and the skin side of the joining means 30 is exposed to the skin side through this opening.
[0056] Here, if the thickness of the top sheet 2 is t2, then the skin-side surface of the bonding means 30 exposed at the through hole 2h (opening) is located t2 on the non-skin side in the thickness direction compared to the skin-side surface of the top sheet 2. In other words, the height of the surface of the pad 1 that is exposed to the skin side in the overlapping region OR is t2 lower than the surrounding area at the through hole 2h (opening). In addition, in the overlapping region OR, a side sheet 4 (leak-proof wall portion 6) may be positioned on the skin side of the top sheet 2 (see Figures 2 and 4). Therefore, in this embodiment, the skin-side surface of the bonding means 30 has a portion that is located on the non-skin side compared to the portion of the overlapping region OR that is located on the skin side in the thickness direction. Hereinafter, the portion of the skin-side surface of the bonding means 30 that is located on the non-skin side compared to the portion of the overlapping region OR that is located on the skin side in the thickness direction will also be called the "low portion 30s".
[0057] When wearing such a pad 1, the part closest to the skin is likely to come into contact with the wearer's skin or clothing. In other words, the skin-facing sides of the top sheet 2 and side sheets 4 are more likely to come into direct contact with the wearer's skin, etc. As a result, foreign matter such as sebum, lint, and dust is more likely to adhere to the skin-facing sides of the top sheet 2, etc. On the other hand, at the through hole 2h (opening), the skin-facing side (lower part 30s) of the bonding means 30 is positioned lower (non-skin side) than the skin-facing sides of the top sheet 2, etc., thus reducing the likelihood of contact with the wearer's skin or clothing. In other words, when wearing the pad 1, at least a part of the bonding means 30 (lower part 30s) has a lower probability of foreign matter such as sebum and lint adhering to its surface compared to the position closest to the skin in the overlapping region OR (skin-facing side of the top sheet 2, etc.). Therefore, a decrease in the bonding force of the bonding means 30 at the lower part 30s is suppressed, making it easier to press the bonding means 30, 30' together as shown in Figure 3B. This allows for hygienic disposal of pad 1, such as when discarding it, by closing the skin-facing side where excrement has adhered.
[0058] Furthermore, it is preferable that the portion of the overlapping region OR that is located on the non-skin side (lower portion 30s) is located on the non-skin side than the portion located on the skin side, and that in the width direction, it straddles the central position CC of the pad 1. In Figure 4, among the multiple through holes 2h (openings), one of the through holes 2h is arranged to straddle the central position CC of the pad 1. In this way, a lower portion 30s is formed in the central part of the joining means 30 in the width direction, making it difficult for foreign matter to adhere, and thus suppressing a decrease in the joining force of the joining means 30 in the central part. And because the joining force in the central part of the joining means 30 in the width direction does not decrease easily, when the joining means 30 is pressed from the non-skin side toward the skin side, it becomes easier to press the skin side of the joining means 30 against the opposing surface. This makes it easier to perform the operation of pressing the joining means 30, 30' toward each other, as shown in Figure 3B.
[0059] Furthermore, the region circumscribing the multiple through holes 2h (the region enclosed by the dotted line in Figure 4) may also be considered as the lower portion 30s. That is, even when the region where the multiple through holes 2h are located is collectively considered as the lower portion 30s, the lower portion 30s is arranged to straddle the central position CC in the width direction. In this case as well, the bonding force in the central part in the width direction is less likely to decrease, making it easier to press the skin side (lower portion 30s) of the bonding means 30 against the opposing surface.
[0060] Furthermore, when the pad 1 is viewed in the thickness direction while unfolded and extended, at least a portion of the bonding means 30 (30') is covered from the skin side by a cover member such as a top sheet 2. By providing a cover member with a predetermined thickness, a step is more easily formed between the skin side of the cover member (the part closest to the skin) and the skin side of the bonding means 30 (lower part 30s) in the thickness direction, thereby reducing the probability of foreign matter such as sebum and lint adhering to the lower part 30s. In addition, foreign matter such as lint is less likely to adhere to the portion of the bonding means 30 (30') covered by the cover member such as the top sheet 2, and the bonding strength is less likely to decrease. For example, after using the pad 1, if the cover member is peeled off or rolled up from the skin side of the bonding means 30 (30') and moved, the bonding can be performed using a wide area of the skin side of the bonding means 30 (30') where the bonding strength has not decreased (see Figures 10 and 12, etc., described later).
[0061] In the pad 1 of this embodiment, the top sheet 2 functions as a cover member that covers the skin side of the bonding means 30 (30'), so there is no need to provide any other sheet members as cover members. If the bonding means 30 (30') were located on the skin side of the top sheet 2, it would be necessary to provide an additional cover member to cover the bonding means 30 (30') from the skin side. In contrast, in pad 1, since the bonding means 30 is positioned between the absorbent core 10 and the top sheet 2 in the thickness direction, no extra cover members are needed, and material costs and manufacturing costs can be suppressed. Furthermore, when wearing pad 1, there are no extra cover members between the wearer's skin and the top sheet 2, so the feel and fit are less likely to deteriorate, and the user is less likely to experience discomfort.
[0062] Furthermore, in the overlapping region OR, the top sheet 2 is provided with multiple through holes 2h (openings). As described above, a height difference is formed between the part of the top sheet 2 where through holes 2h are formed and the part where they are not, based on the thickness of the top sheet 2. The part of the skin side surface of the bonding means 30 that overlaps with the through holes 2h is located on the non-skin side of the skin side surface of the top sheet 2 (corresponding to the lower part 30s in Figure 7B), making it difficult for foreign matter to adhere to it. This makes it easier to maintain the bonding force of the bonding means 30 in the part that overlaps with the through holes 2h. Moreover, in the pad 1 of this embodiment, the provision of multiple through holes 2h creates height differences at multiple locations on the top sheet 2. In other words, by overlapping with the through holes 2h, multiple parts located on the non-skin side in the thickness direction (lower parts 30s) are formed, increasing the proportion of the skin side surface of the bonding means 30 where foreign matter is less likely to adhere, making it easier to maintain a large bonding force. This makes it easier to press the portion of the bonding means 30 that overlaps with the through hole 2h (the portion exposed to the skin) against the opposing surface when disposing of the pad 1.
[0063] Furthermore, if the top sheet 2 in the pad 1 is provided with multiple through holes 2h (openings), when viewed in the thickness direction, the joining means 30 will have portions that are covered by the top sheet 2 (cover member) and portions that are not covered. In other words, at least a portion of the joining means 30 will have portions that are not covered by the top sheet 2 (cover member). With such a configuration, at least a portion of the joining means 30 will be exposed to the skin side beforehand, making it possible to join the joining means 30 using the portion exposed to the skin side. That is, the joining means 30 can be joined without removing the cover member that covers the joining means 30 from the skin side, making it easy to press the joining means 30 against opposing surfaces. Note that, as shown in Figure 11 later, the cover member may be formed from a sheet member different from the top sheet 2, and the joining means 30 may have portions that are covered by the cover member and portions that are not covered.
[0064] Furthermore, the ratio of the area of the portion of the one-sided joining means 30 covered by the top sheet 2 (cover member) may be made different from the ratio of the area of the portion of the other-sided joining means 30' covered by the top sheet 2 (cover member). For example, if foreign matter is more likely to adhere to the joining means 30 on the ventral side (one side) than on the dorsal side (the other side), the one-sided joining means 30 may be configured so that the ratio of the area covered by the cover member is larger than that of the other-sided joining means 30'. In this way, the probability of foreign matter adhering to the joining means with a larger ratio of the area covered by the cover member (one-sided joining means 30) is lower compared to the joining means with a smaller ratio of the area covered by the cover member (the other-sided joining means 30'), and the bonding force is less likely to decrease. Therefore, even if a decrease in bonding force occurs in the other-sided joining means 30', the bonding force of the one-sided joining means 30 is not likely to decrease, making it possible to press the two together.
[0065] Furthermore, in pad 1, the one-sided joining means 30 and the other-sided joining means 30' are each covered from the skin side by the top sheet 2. That is, the one-sided joining means 30 and the other-sided joining means 30' are covered by a common cover member (top sheet 2). With this configuration, it is possible to cover both the one-sided joining means 30 and the other-sided joining means 30' with a single cover member (top sheet 2), eliminating the need for extra cover members (sheet members different from the top sheet 2). As a result, the overall structure of pad 1 is simplified, and since no extra sheet members are provided on the skin side that comes into contact with the wearer's skin, the manufacturing cost of pad 1 can be reduced while minimizing discomfort for the wearer.
[0066] Furthermore, it is preferable that the one-sided joining means 30 and the other-sided joining means 30' are arranged to straddle the end of the absorbent core 10 in the longitudinal or widthwise direction. Figure 8 is a cross-sectional view illustrating the arrangement of the joining means 30, 30' and the absorbent core 10. As shown in Figure 8, a step is created in the thickness direction at the end of the absorbent core 10 (the contour of the absorbent core 10). In this case, the portion of the pad 1 that has thickness in the thickness direction due to the absorbent core 10, and where the absorbent core 10 and the joining means 30, 30' overlap when viewed in the thickness direction, is defined as a convex region 303. On the other hand, the portion of the pad 1 that does not have thickness in the thickness direction due to the absence of the absorbent core 10, and where the absorbent core 10 and the joining means 30, 30' do not overlap when viewed in the thickness direction, is defined as a concave region 304.
[0067] The presence of a convex region 303 and a concave region 304 makes it easier for steps to be formed in the bonding means 30, 30' which are positioned across the edges of the absorbent core 10. In other words, when the pad 1 is worn, if the surface of the bonding means 30, 30' comes into contact with the wearer's skin or clothing, the probability of sebum, lint, etc. adhering to the concave region 304 of the bonding means 30, 30' is lower compared to the convex region 303. Therefore, the presence of the concave region 304 of the bonding means 30, 30' makes it less likely for the bonding strength to decrease compared to the case where the concave region 304 is not provided, and makes it easier for the pad 1 to maintain a closed state.
[0068] <Modification of the cover member> The top sheet 2, which has multiple through holes 2h (openings), has been described as a cover member that covers the joining means 30, 30' from the skin side, but the cover member can also be modified as follows.
[0069] Figure 9 is a plan view showing a modified cover member. Figures 10A and 10B are cross-sectional views taken along the line C-C in Figure 9. In this modified example, the top sheet 2, which serves as the cover member, does not have through holes 2h (openings). That is, the entirety of the joining means 30, 30' is covered from the skin side by the top sheet 2, and the joining means 30, 30' do not have any portion exposed to the skin side, at least in the overlapping region OR. The top sheet 2 has a break guide line 2cl in the region that overlaps with the joining means 30, 30' when viewed in the thickness direction. The break guide line 2cl is composed of perforations along the periphery of a rectangular region, for example, as shown in Figure 9, and the user can easily cut the top sheet 2 along the break guide line 2cl (perforations) with their bare hands without using tools such as scissors.
[0070] When the break guide line 2cl (perforation) is not torn, the entire bonding means 30 is covered from the skin side by the top sheet 2 (cover member), as shown in Figure 10A. Therefore, when the pad 1 is worn in this state, foreign matter such as sebum and lint is less likely to adhere to the skin side of the bonding means 30, and the bonding strength of the bonding means 30 is less likely to decrease. When discarding the pad 1 after use (after wearing), the top sheet 2 is torn along the break guide line 2cl (perforation) to separate the area surrounded by the break guide line 2cl (perforation). Then, as shown in Figure 10B, the skin side (low part 30s) of the bonding means 30 is exposed in the part where the top sheet 2 has been separated. Since this exposed skin side (low part 30s) is free of foreign matter such as lint and the bonding strength is not reduced, when the pad 1 is folded in half lengthwise (see Figure 3B), it can be firmly bonded to the opposing surfaces.
[0071] In other words, in the modified configuration, the skin-facing side of the bonding means 30, which is located on the non-skin side of the top sheet 2, which is located on the skin-facing side of the overlapping region OR, is covered by the top sheet 2 (cover member). This makes it easier to suppress a decrease in the bonding force of the bonding means 30 when the pad 1 is worn. Furthermore, when the pad 1 is discarded, a portion of the top sheet 2 (cover member) can be cut along the break guide line 2cl (perforation) and moved (removed) away from the skin side of the bonding means 30, thereby exposing a wider portion of the skin-facing side of the bonding means 30 where the bonding force has not decreased. This allows the bonding means 30 to be strongly pressed against the opposing surface.
[0072] Furthermore, in the modified configuration, as shown in Figure 9, the entire joining means 30 is covered by the top sheet 2 (cover member) in a plan view. Since foreign matter is less likely to adhere to the portion of the joining means 30 covered by the top sheet 2 (cover member), the reduction in joining force is more easily suppressed. Therefore, if the entire joining means 30 is covered by the top sheet 2 (cover member), the reduction in joining force can be suppressed for the entire joining means 30. This makes it easier to press the joining means 30 more strongly against opposing surfaces.
[0073] ===Second Embodiment=== In the second embodiment, a urine absorption pad 1 with a different configuration, such as the bonding means 30, from the first embodiment will be described. In the pad 1 of the second embodiment, bonding means 30, 30' are formed by applying a bonding agent 31 to a predetermined area on the skin side of the top sheet 2. That is, the bonding means 30, 30' are provided on the skin side of the top sheet 2. In addition, a cover portion 50, which is a sheet member different from the top sheet 2, is provided as a cover member that covers the bonding means 30, 30' from the skin side. However, as will be described later, the cover portion 50 is not necessarily provided in the pad 1 of the second embodiment. In the pad 1 of the second embodiment, the configuration other than the bonding means 30, 30' and the cover portion 50 is substantially the same as that of the pad 1 described in the first embodiment.
[0074] Figure 11 is a plan view illustrating the joining means 30 and cover portion 50 of the urine absorption pad 1 according to the second embodiment. Figures 12A and 12B are cross-sectional views taken along the line Y-Y in Figure 11. The cover portion 50 is a sheet member made of nonwoven fabric, release paper, etc., which is placed on top of the joining means 30 on the skin side, and a part of the peripheral edge of the cover portion 50 is fixed to the skin side of the top sheet 2 and side sheet 4 by an adhesive such as a hot melt adhesive. In Figure 11, the cover joining portion 51 is formed by applying adhesive to one side in the longitudinal direction and both sides in the width direction, and the cover portion 50 is fixed to the skin side of the pad 1 via the cover joining portion 51. When the pad 1 is viewed in the thickness direction in its unfolded and extended state, the cover portion 50 has a portion that overlaps with the joining means 30, as shown in Figure 11. That is, at least a part of the joining means 30 is covered from the skin side by the cover portion 50 (cover member).
[0075] In Figure 12A, if the area where the bonding means 30 is covered from the skin side by the cover portion 50 is called the covered area CA, then in the overlapping area OR, the covered area CA is located on the skin side in the thickness direction compared to the bonding means 30. In other words, the skin side of the bonding means 30 has a portion (lower portion 30s) that is located on the non-skin side than the portion of the overlapping area OR that is on the skin side in the thickness direction (the skin side of the cover portion 50). Therefore, when wearing the pad 1 of the second embodiment, the probability of foreign matter such as sebum and fiber debris adhering to the surface of the lower portion 30s of the bonding means 30 is lower compared to the covered area CA, and the decrease in bonding strength in the lower portion 30s is suppressed.
[0076] Furthermore, in the covered area CA, the skin-side surface of the bonding means 30 is covered by the cover portion 50, making it more difficult for foreign matter to adhere. In other words, the reduction in bonding strength is suppressed over a wide area of the skin-side surface of the bonding means 30. When disposing of the pad 1, as shown in Figure 12B, the cover portion 50 can be peeled back and moved away from the skin side of the bonding means 30, thereby widely exposing the skin-side surface of the bonding means 30. This makes it possible to strongly press the bonding means 30 against the opposing surface when the pad 1 is folded in half lengthwise (see Figure 3B), allowing the pad 1 to be disposed of hygienically with the skin-side surface closed.
[0077] In addition, in the pad 1 of the second embodiment, the cover portion 50 does not necessarily have to be provided on both sides in the longitudinal direction, and the cover portion 50 may be provided on only one side in the longitudinal direction. For example, the cover portion 50 may be provided on the skin side of the one-side joining means 30 which is located on one side in the longitudinal direction, but the cover portion 50 may not be provided on the skin side of the other-side joining means 30' which is located on the other side in the longitudinal direction. In other words, the one-side joining means 30 may have a portion covered by the cover portion 50 (cover member), and the other-side joining means 30' may not have a portion covered by the cover portion 50 (cover member).
[0078] Even in such cases, the joining means 30 covered by the cover portion 50 (one-side joining means 30) maintains its joining force more easily than the other side (other-side joining means 30'). Therefore, even if foreign matter adheres to the other-side joining means 30' and the joining force decreases, it is still possible to press the one-side joining means 30 and the other-side joining means 30' together. Furthermore, since there is no need to provide a cover portion 50 on the other-side joining means 30', the manufacturing cost of the pad 1 can be reduced.
[0079] Furthermore, the cover portion 50 (cover member) may not be provided on both sides in the longitudinal direction. Figures 13A and 13B illustrate an example in which the cover portion 50 is not provided in the urine absorption pad 1 of the second embodiment. Figure 13A is a plan view of the pad 1 showing the one-side joining means 30 and its surroundings, and Figure 13B is a cross-sectional view taken along the line E-E in Figure 13A.
[0080] In the pad 1 shown in Figures 13A and 13B, the skin side of the one-side joining means 30 does not have a cover portion 50 (cover member). Also, when viewed in the thickness direction, the one-side joining means 30 has a portion that overlaps with the skin side of the side sheet 4 (leak-proof wall portion 6). For example, when the adhesive 31 forming the one-side joining means 30 is applied from the skin side of the top sheet 2 and the side sheet 4, both ends of the one-side joining means 30 in the width direction may be laminated on the skin side of the side sheet 4, as shown in Figure 13B. Hereinafter, the region in which the one-side joining means 30 and the side sheet 4 overlap when viewed in the thickness direction will also be called the laminated region SA.
[0081] As shown in Figure 13B, the skin-facing side of the one-sided bonding means 30 is located closer to the skin in the thickness direction than other areas in the laminated region SA. Furthermore, the skin-facing side of the one-sided bonding means 30 has a portion (lower portion 30s) that is located closer to the skin in the thickness direction than the portion (laminated region SA) of the overlapping region OR. Therefore, when the pad 1 is worn, foreign matter such as sebum and lint is more likely to adhere to the laminated region SA, which is closer to the wearer's skin, compared to the lower portion 30s. In other words, foreign matter is less likely to adhere to the lower portion 30s of the skin-facing side of the one-sided bonding means 30, so the bonding force is less likely to decrease. Therefore, it becomes easier to press the bonding means 30, 30' together in opposition at the lower portion 30s, as shown in Figure 3B. This allows for hygienic disposal of the pad 1 with the skin-facing side where excrement has adhered closed when it is time to dispose of it.
[0082] Next, Figures 14A and 14B illustrate another example in which the cover portion 50 is not provided in the urine absorption pad 1 of the second embodiment. Figure 14A is a plan view of the pad 1 showing the one-sided joining means 30 and its surroundings, and Figure 14B is a cross-sectional view taken along the line F-F in Figure 14A.
[0083] In the pad 1 shown in Figures 14A and 14B, the skin-facing side of the one-sided joining means 30 does not have a cover portion 50 (cover member). Also, when viewed in the thickness direction, the one-sided joining means 30 has a portion that overlaps with the non-skin side of the side sheet 4 (leak-proof wall portion 6). Similar to the case of Figure 13, if the region where the one-sided joining means 30 and the side sheet 4 overlap when viewed in the thickness direction is called the laminated region SA, then in the laminated region SA, the skin-facing side of the side sheet 4 is located closer to the skin in the thickness direction than the skin-facing side of the one-sided joining means 30. That is, in the case of Figure 14 as well, the skin-facing side of the one-sided joining means 30 has a portion (lower portion 30s) that is located closer to the skin in the thickness direction than the portion (laminated region SA) of the overlapping region OR. Therefore, when the pad 1 is worn, foreign matter such as sebum and fiber debris is more likely to adhere to the laminated region SA, which is closer to the wearer's skin, compared to the lower portion 30s. In other words, foreign matter is less likely to adhere to the lower part 30s of the skin-facing side of the one-sided joining means 30, thus preventing a decrease in bonding strength. This makes it easier to press the joining means 30, 30' together, allowing for hygienic disposal of the pad 1 with the skin-facing side where excrement has adhered closed when discarding it.
[0084] Furthermore, in the pad 1 of the second embodiment, the top sheet 2 may be configured to have irregularities on the skin-facing side. Figure 15 is a cross-sectional view illustrating the configuration of the joining means 30, 30' and the top sheet 2. Figure 15 corresponds, for example, to an enlarged view of region G in Figure 13B. In Figure 15, the top sheet 2 has a plurality of sheet protrusions 201 and sheet recesses 202 that are convex on the skin-facing side in the thickness direction of the pad 1. The one-sided joining means 30 is provided overlapping the skin-facing side of the sheet protrusions 201 and sheet recesses 202. In this case, of the joining means 30, 30', a protrusion 301 is formed in the portion that overlaps the skin-facing side of the sheet protrusions 201, and a recess 302 is formed in the portion that overlaps the skin-facing side of the sheet recesses 202.
[0085] With this configuration, when the pad 1 is worn, if the surfaces of the bonding means 30, 30' come into contact with the wearer's skin or clothing, foreign matter such as sebum and lint is more likely to adhere to the protrusions 301 located on the skin side in the thickness direction of the bonding means 30, 30', while foreign matter is less likely to adhere to the recesses 302 located on the non-skin side of the protrusions 301. In other words, the probability of sebum, lint, etc. adhering to the recesses 302 is lower compared to the protrusions 301. Therefore, the bonding strength of the recesses 302 on the skin side of the bonding means 30, 30' is less likely to decrease. This makes it easier to maintain the closed state of the pad 1.
[0086] <Regarding the bonding force of bonding means 30 and 30'> Figure 16 is a diagram illustrating the operation and effect of the pad 1 to which bonding means 30 and 30' are applied. Figure 16A is a view from the thickness direction of the pad 1 when it is folded in half along the fold line FL so that one bonding means 30 and the other bonding means 30' face each other, and the two are bonded together. Figure 16B is a diagram showing the process of separating the one bonding means 30 and the other bonding means 30' when unfolding the pad 1.
[0087] In this embodiment, when the pad 1 is folded in half along the center line CL (fold line FL), as shown in Figure 16A, at least a portion of the central region Lc of one side joining means 30 and the central region Lc' of the other side joining means 30' overlap in the thickness direction. Although not shown, in the width direction, similar to the longitudinal direction, at least a portion of the central region Wc of one side joining means 30 and the central region Wc' of the other side joining means 30' also overlap.
[0088] The one-sided joining means 30 is divided into three equal parts in the longitudinal direction and the width direction. In the longitudinal direction, these are the first longitudinal adjacent region L1, the longitudinal central region Lc, and the second longitudinal adjacent region L2, starting from one side. In the width direction, these are the first width adjacent region W1, the width central region Wc, and the second width adjacent region W2. (See Figure 6) There are differences in joining strength among these regions. In this embodiment, the joining strength of the first adjacent regions L1 and W1, which are adjacent to one side of the central regions Lc and Wc, is weaker than the joining strength of the central regions Lc and Wc in the longitudinal and width directions. Furthermore, the joining strength of the second adjacent regions L2 and W2, which are adjacent to the other side of the central regions Lc and Wc, is weaker than the joining strength of the central regions Lc and Wc.
[0089] The magnitude of the bonding force in each region, such as the first longitudinal adjacent region L1 and the longitudinal central region Lc, can be evaluated by the amount (basis weight) of the bonding agent 31 per unit area in each region. In each region, the greater the amount (basis weight) of the bonding agent 31 per unit area, the greater the bonding force.
[0090] Alternatively, the magnitude of the bonding force in each region may be evaluated using a measuring instrument.
[0091] When measuring the magnitude of the bonding force in the first longitudinal adjacent region L1, the longitudinal central region Lc, and the second longitudinal adjacent region L2, two sample pieces are prepared. The first sample piece is a cut-out of the region to be measured from the first longitudinal adjacent region L1, the longitudinal central region Lc, etc. The second sample piece is a nonwoven fabric to which a uniform amount of bonding agent 31 has been applied.
[0092] By attaching masking tape to the end of the sample piece, a holding portion (grasping portion) is formed at the end of the sample piece. Next, the two sample pieces are placed on top of each other, and the two sample pieces are joined together by rolling a 2 kg roller at 5 mm / second from the opposite side of the holding portion.
[0093] Next, the sample piece is held in the chuck of a tensile testing machine (for example, an Instron universal material testing machine), and the two sample pieces are separated by pulling the two holding parts apart in the longitudinal direction. The tensile load at the time of separation is then measured. The average value of the tensile load represents the magnitude of the bonding force in the area being measured.
[0094] The joint force can be measured in the same manner for the first adjacent width region W1, the central width region Wc, and the second adjacent width region W2.
[0095] Before use (during packaging), the pad 1 is closed, and for example, as shown in Figure 16A, the one-sided joining means 30 and the other-sided joining means 30' are in contact. When using the pad 1, as shown in B, the user grasps the areas of the dry edges D provided at both ends in the longitudinal direction of the pad 1 and pulls it apart toward the center in the longitudinal direction.
[0096] In this case, if the bonding force at the beginning of the peeling process is strong, it may be difficult to open when unfolding, and this may be particularly difficult for elderly users with reduced dexterity in their fingers. However, in the pad 1 of this embodiment, the bonding force of the first longitudinal adjacent regions L1 and L1' in the one-side bonding means 30 is weaker than the bonding force of the longitudinal central regions Lc and Lc'. Therefore, it can be peeled and unfolded with relatively less force compared to when the bonding force of the first longitudinal adjacent regions L1 and L1' in the one-side bonding means 30 is stronger than, or the same as, the bonding force of the longitudinal central regions Lc and Lc'. Furthermore, because a dry edge D is provided, it is easier for the user to grasp and even easier to peel off.
[0097] In this embodiment, since the second adjacent region L2 with weak bonding force is located on the longitudinal centerline CL side, the pad 1 can also be peeled away from the leg-around elastic member 5 toward the end. In this case as well, the same effects as described above are achieved. Furthermore, since a dry edge D is provided over a predetermined distance d from the end in the width direction of the pad 1, the ease of peeling can be improved even when performing such peeling.
[0098] Furthermore, the central region (first portion 34) of both the one-sided joining means 30 and the other-sided joining means 30' has a stronger joining force than the adjacent region. As a result, when the pad 1 is folded in half along the fold line FL after use or disposal, it is easier to maintain the state in which the pad 1 covers the excrement on the side of the skin by bringing one end of the pad 1 into contact with the other end.
[0099] Furthermore, the configuration is not limited to the above. The coating amount in either the first adjacent region L1, W1 or the second adjacent region L2, W2 may be less than that in the central region Lc, Wc. Alternatively, the difference in coating amount may be in only one of the directions, either the longitudinal or the width. For example, the coating amount in the second adjacent region L2 (second longitudinal adjacent region) in the longitudinal direction may be less than that in the central region Lc. In this case, when the user peels off the pad 1, they can easily unfold it by peeling it off from the second adjacent region L2, which has weaker bonding force.
[0100] Furthermore, in the pad 1 of this embodiment, when the pad 1 is folded in half along the center line CL (fold line FL), the central regions Lc and Wc of the one-sided joining means 30 and the central regions Lc' and Wc' of the other-sided joining means 30' overlap in the thickness direction. Because the central regions overlap, when disposing of the pad 1, it is easier to maintain the state in which the pad 1 is folded in half and covers the excrement on the side of the skin with the pad 1.
[0101] Furthermore, the same effect and benefits can be achieved even when the pad 1 is folded in half at the center position in the width direction (a fold line along the center line in the width direction). In this case, two joining means should be provided on one side and the other side in the width direction, with the center line in the width direction as the reference.
[0102] Alternatively, the joining means 30 on one side may have varying degrees of joining force, while the joining means 30' on the other side may have a uniform joining force.
[0103] Furthermore, regarding the magnitude of the joining force in the longitudinal and width directions of the one-sided joining means 30, the value obtained by dividing the difference between the joining force of the longitudinal central region Lc and the joining force of the first longitudinal adjacent region L1 by the longitudinal length of the longitudinal central region Lc is greater than the value obtained by dividing the difference between the joining force of the width central region Wc and the joining force of the first width adjacent region W1 by the width direction length of the width central region Wc. In other words, the difference in joining force per unit length is greater in the longitudinal direction than in the width direction.
[0104] In the longitudinal direction, the difference in bonding force per unit length between the central region Lc (Lc') and the adjacent region L1 (L1') is large. Therefore, even when the pad 1 is folded along the fold line FL along the width direction before use, and the one-sided bonding means 30 and the other-sided bonding means 30' of the pad 1 are joined, it is possible to easily separate the one-sided bonding means 30 and the other-sided bonding means 30' and unfold the pad in the longitudinal direction. On the other hand, as shown in the configuration of Figure 6, in the width direction, the difference in bonding force per unit length between the central region Wc (Wc') and the adjacent region W1 (W1') is small. Therefore, when discarding the pad 1, it is possible to easily maintain the state in which the excrement on the skin side is covered by the pad 1 by joining the one-sided bonding means 30 and the other-sided bonding means 30' provided on the skin side.
[0105] Furthermore, in this embodiment, the pad 1 is made possible by providing a first portion 34 and a second portion 35 that is thinner than the first portion 34 on the joining means 30 and 30', thereby forming convex and concave portions. As a result, when the joining means 30 on one side and the joining means 30' on the other side of the pad 1 are joined before use, the joining means 30 on one side and the joining means 30' on the other side can be easily separated and unfolded in the longitudinal direction. In other words, by forming irregularities with the adhesive 31, the concave portion 33, which is thinner in the thickness direction, can be made easier to separate.
[0106] Furthermore, in the pad 1 of this embodiment, since the joining means 30 and 30' are provided at the ends of the pad 1, it is easier to peel off and more difficult to open when disposing of the pad than when the joining means 30 and 30' are provided in the center.
[0107] <Modified Examples of Joining Means 30 and 30'> Figure 17 is an explanatory diagram showing modified examples of joining means 30 and 30' of the pad 1. Figures 17A and 17B show self-adhesive quadrilateral joining means 30 and 30', respectively. The area to which the adhesive 31 is applied corresponds to the region where the joining portion is provided in the modified example of this embodiment.
[0108] In the modified example shown in Figure 17A, the longitudinal central region Lc is an area on the skin-side surface sheet 2 where the adhesive 31 is applied uniformly in a roughly rectangular shape that is long in the width direction (so-called solid coating). In addition, the first longitudinal adjacent region L1 and the second longitudinal adjacent region L2 are coated with the adhesive 31 in a wave-like pattern, as shown in Figure 17A.
[0109] In this case, the bonding force of the first longitudinal adjacent region L1 and the second longitudinal adjacent region L2, which have margins due to the application of the bonding agent 31 in a wave-like pattern, is weaker than that of the longitudinal central region Lc, which is coated solidly. As a result, while ensuring ease of peeling when unfolding the pad 1, the bonding force of the longitudinal central region Lc is stronger than that of the adjacent regions, so that when the pad 1 is folded for disposal, the excrement on the side of the skin can be kept covered by the pad 1.
[0110] Next, in the modified example shown in Figure 17B, the longitudinal central region Lc is a uniformly coated area, similar to the modified example in Figure 17A. Then, as shown in Figure 17B, the first longitudinal adjacent region L1 and the second longitudinal adjacent region L2 have the adhesive 31 partially applied in the width direction, leaving a blank area.
[0111] In this case, the bonding force of the first longitudinal adjacent region L1 and the second longitudinal adjacent region L2, which have a margin due to the bonding agent 31 being applied only to a portion of the width direction, is weaker than that of the longitudinal central region Lc, which is fully coated. As a result, while ensuring ease of peeling when unfolding the pad 1, the bonding force of the longitudinal central region Lc is stronger than that of the adjacent regions, so that when the pad 1 is folded for disposal, the excrement on the side of the skin can be kept covered by the pad 1.
[0112] In these modified examples, the amount of coating per unit area and the arrangement pattern using margins for the joining means 30 in the central regions Lc and Wc differ from the arrangement pattern of the joining means 30 in the first adjacent regions L1 and W1 or the second adjacent regions L2 and W2.
[0113] ===Other=== The above embodiments are provided to facilitate understanding of the present invention and are not intended to limit the interpretation of the present invention. The present invention can be modified and improved without departing from its spirit, and it goes without saying that the present invention includes equivalents thereof.
[0114] 1 Urine pad (pad, absorbent material), 2 Surface sheet (top sheet) (cover member), 2h Through hole (opening), 2cl Breakage guide line, 3 Back sheet, 4 Side sheet, 5 Leg-around elastic member, 6 Leak-proof wall section, 7 Leak-proof wall elastic member, 8 Adhesive area, 10 Absorbent core, 11 Core wrap sheet, 20 Fixing member, 30 One-side joining means, 30s Bottom section, 30' Other-side joining means, 31 Bonding agent, 50 Cover section, 51 Cover joining section, OR Overlapping area, CA Covered area, SA Laminated area, Lc Longitudinal central area, Wc Width central area, L1 First longitudinal adjacent area, W1 First width adjacent area, L2 Second longitudinal adjacent area, W2 Second width adjacent area
Claims
1. An absorbent article having a liquid-absorbing core, having longitudinal, width, and thickness directions that are mutually orthogonal in an unfolded state, wherein the article has a bonding means on its skin-facing side that can be bonded to a part of the absorbent article when discarded, and in an unfolded and extended state, it has an overlapping region that overlaps with the bonding means in the longitudinal direction, and the skin-facing side of the bonding means has a portion that is located on the non-skin side of the overlapping region in the thickness direction than the portion that is located on the skin side.
2. An absorbent article according to claim 1, characterized in that, of the skin-facing side of the joining means, the portion located on the non-skin side than the portion located on the skin side straddles the central position of the absorbent article in the width direction.
3. An absorbent article according to claim 1 or 2, characterized in that, when viewed in the thickness direction, it has a cover member that covers at least a portion of the joining means from the skin side.
4. An absorbent article according to claim 3, wherein the cover member is a top sheet provided on the skin side of the absorbent core, and the bonding means is disposed between the absorbent core and the top sheet in the thickness direction.
5. An absorbent article according to claim 4, characterized in that the top sheet has an opening that penetrates in the thickness direction in the overlapping region.
6. An absorbent article according to claim 4, characterized in that the top sheet has a break guide line in the overlapping region for breaking the top sheet.
7. An absorbent article according to claim 3, characterized in that, when viewed in the thickness direction, the entire bonding means is covered by the cover member.
8. An absorbent article according to claim 3, characterized in that, when viewed in the thickness direction, at least a portion of the joining means is not covered by the cover member.
9. An absorbent article according to claim 8, wherein the joining means comprises a one-side joining means provided on one side in the longitudinal direction and a other-side joining means provided on the other side in the longitudinal direction, characterized in that the ratio of the area of the portion of the one-side joining means covered by the cover member to the total area of the one-side joining means and the ratio of the area of the portion of the other-side joining means covered by the cover member to the total area of the other-side joining means are different.
10. An absorbent article according to claim 3, wherein the joining means comprises a one-side joining means provided on one side in the longitudinal direction and a other-side joining means provided on the other side in the longitudinal direction, and the one-side joining means and the other-side joining means are covered by a common cover member.
11. An absorbent article according to claim 3, wherein the joining means comprises a one-side joining means provided on one side in the longitudinal direction and a other-side joining means provided on the other side in the longitudinal direction, wherein the one-side joining means has a portion covered by the cover member, and the other-side joining means does not have a portion covered by the cover member.
12. An absorbent article according to claim 1 or 2, characterized in that, in at least one of the longitudinal direction and the width direction, the joining means is arranged to straddle the end of the absorbent core.
13. An absorbent article according to claim 1 or 2, wherein the absorbent core has a pair of side sheets at both ends in the width direction, and the joining means has a portion that overlaps with the side sheets and is located on the skin side in the thickness direction compared to the side sheets when viewed in the thickness direction.
14. An absorbent article according to claim 1 or 2, wherein the absorbent core has a pair of side sheets at both ends in the width direction, and the joining means has a portion that overlaps with the side sheets and is located on the non-skin side in the thickness direction of the side sheets when viewed in the thickness direction.
15. An absorbent article according to claim 1 or 2, wherein the surface of the joining means has a plurality of convex portions that are convex in the thickness direction and concave portions that are concave in the thickness direction, and in the overlapping region, the convex portions are located closest to the skin in the thickness direction.