Absorbent sheet

Abstract

This pet sheet comprises: a liquid-permeable front surface sheet; a back surface sheet disposed at a position opposite the front surface sheet; and an absorbent body disposed between the front surface sheet and the back surface sheet. The absorbent body has: an absorbent core; a core wrap including a front surface cover part that covers a front surface sheet-side surface of the absorbent core; and a wooden member that is a first antibacterial agent and is disposed between the absorbent core and the front surface cover part. The absorbent core has an upper pulp layer containing pulp, and an antibacterial agent that is a second antibacterial agent disposed closer to the back surface sheet side than the upper pulp layer.

Description

Absorbent sheet

[0001] The present disclosure relates to an absorbent sheet for pets.

[0002] Patent Document 1 discloses a pet excrement sheet including an absorbent core in which an antibacterial agent is disposed between two pulp layers.

[0003] Japanese Unexamined Patent Application Publication No. 2020-188698

[0004] In the configuration where the antibacterial agent is disposed only in the central portion of the absorbent core as described above, there is a risk that the antibacterial performance may not be sufficiently exhibited at the upper portion (topsheet side) of the absorbent core. On the other hand, when the antibacterial agent is disposed in a portion close to the topsheet, the antibacterial agent may come into contact with the pet's skin (such as the tips of the paws) and cause irritation to the pet's skin.

[0005] An object of the present disclosure is to provide an absorbent sheet for pets that can improve antibacterial performance while reducing irritation to the pet's skin.

[0006] An absorbent sheet according to one aspect includes a liquid-permeable topsheet, a backsheet disposed at a position facing the topsheet, and an absorber disposed between the topsheet and the backsheet. The absorber has an absorbent core, a cover sheet including a surface cover portion that covers the surface of the absorbent core on the topsheet side, and a first antibacterial agent disposed between the absorbent core and the surface cover portion. The absorbent core has a first pulp layer containing pulp, and a second antibacterial agent disposed on the backsheet side relative to the first pulp layer.

[0007] According to the present disclosure, it is possible to provide an absorbent sheet for pets that can improve antibacterial performance while reducing irritation to the pet's skin.

[0008] It is a plan view of a pet sheet according to one embodiment. It is a diagram schematically showing the cross-sectional structure of the pet sheet taken along line II-II in FIG. 1. It is a diagram schematically showing the cross-sectional structure of the pet sheet taken along line III-III in FIG. 1. It is an image showing an example of a wood member (wood flour).

[0009] At least the following aspects will become apparent from the descriptions of the present specification and the accompanying drawings.

[0010] [1] An absorbent sheet for pets comprising: a liquid-permeable surface sheet; a back sheet disposed opposite to the surface sheet; and an absorbent body disposed between the surface sheet and the back sheet, wherein the absorbent body comprises an absorbent core; a cover sheet including a surface cover portion that covers the surface side of the absorbent core; and a first antibacterial agent disposed between the absorbent core and the surface cover portion, wherein the absorbent core comprises a first pulp layer containing pulp and a second antibacterial agent disposed on the back sheet side of the first pulp layer.

[0011] In the absorbent sheet for pets described in [1] above, in addition to the antibacterial agent (second antibacterial agent) placed after the first pulp layer (on the back sheet side), an antibacterial agent (first antibacterial agent) is also placed before the first pulp layer. This allows for antibacterial performance not only against urine that has passed through the first pulp layer, but also against urine that has not yet penetrated the first pulp layer, thanks to the first antibacterial agent. Furthermore, since the first antibacterial agent is placed inside the absorbent body (between the surface cover and the absorbent core) rather than on the outside of the absorbent body, contact between the first antibacterial agent and the pet's skin (paws, etc.) on the surface sheet is suppressed. Therefore, the above absorbent sheet can improve antibacterial performance while reducing irritation to the pet's skin.

[0012] [2] The absorbent sheet of [1], wherein the first antibacterial agent comprises a plurality of powders, and the surface cover portion is tissue.

[0013] According to the configuration described in [2] above, by using a powdered first antibacterial agent, the surface area of ​​the first antibacterial agent can be increased, and the antibacterial performance of the first antibacterial agent can be suitably exhibited. Furthermore, by constructing the surface cover part with tissue, it is possible to suppress the powdered first antibacterial agent from slipping through the surface cover part and being discharged to the outside of the absorbent material.

[0014] [3] The absorbent sheet of [1] or [2] wherein the antibacterial activity value of the first antibacterial agent is lower than the antibacterial activity value of the second antibacterial agent.

[0015] According to the configuration described in [3] above, even if the first antibacterial agent, which is closer to the pet's skin (i.e., located on the surface sheet side), comes into contact with the pet's skin, the antibacterial power (antibacterial activity value) of the first antibacterial agent is weaker than that of the second antibacterial agent, thus reducing irritation to the pet's skin.

[0016] [4] The first antibacterial agent comprises a plurality of wood powders, wherein the plurality of wood powders have a fiber length longer than the fiber length of the pulp contained in the first pulp layer, and is an absorbent sheet according to any of [1] to [3].

[0017] According to the configuration described in [4] above, the first antibacterial agent can be suitably maintained on the surface layer (surface cover side) of the first pulp layer, thereby allowing the antibacterial function against urine before it penetrates the first pulp layer to be suitably exhibited.

[0018] [5] The absorbent sheet according to any one of [1] to [4], wherein the absorbent core further comprises a second pulp layer disposed on the back sheet side of the first pulp layer, the second pulp layer comprises pulp and a superabsorbent polymer, and the second antimicrobial agent comprises an antimicrobial agent disposed between the first pulp layer and the second pulp layer.

[0019] According to the configuration described in [5] above, the first pulp layer diffuses the urine, the antibacterial agent (second antibacterial agent) placed between the first pulp layer and the second pulp layer exhibits suitable antibacterial performance against the urine, and finally the superabsorbent polymer provided in the second pulp layer effectively absorbs the urine.

[0020] [6] The absorbent sheet of [5] wherein the basis weight of the pulp contained in the first pulp layer is greater than the basis weight of the pulp contained in the second pulp layer.

[0021] According to the configuration described in [6] above, by making the basis weight of the first pulp layer relatively large, the liquid diffusion performance of urine in the first pulp layer can be improved. This makes it possible to improve the urine absorption performance of the subsequent second pulp layer (superabsorbent polymer).

[0022] [7] The absorbent sheet of [5] or [6] wherein the superabsorbent polymer contained in the second pulp layer is antibacterial, and the second antibacterial agent comprises the antibacterial agent disposed between the first pulp layer and the second pulp layer, and the superabsorbent polymer contained in the second pulp layer.

[0023] According to the configuration described in [7] above, by providing the second antibacterial agent between the first pulp layer and the second pulp layer, and also providing it inside the subsequent second pulp layer, the antibacterial performance against urine after it has passed through the first pulp layer can be effectively demonstrated.

[0024] Embodiments of this disclosure will be described in detail below with reference to the drawings. In the following description, the same reference numerals will be used for identical or equivalent elements, and redundant explanations will be omitted. The drawings may be simplified or exaggerated in part for ease of understanding, and the dimensional ratios are not limited to those shown in the drawings.

[0025] Referring to Figures 1 to 3, a pet sheet 1, which is an absorbent sheet for pets according to one embodiment, will be described. The pet sheet 1 is a sheet that has the function of absorbing animal excrement (mainly urine). The animals to which the pet sheet 1 is applied are, for example, animals kept as pets, and may be mammals such as dogs, cats, rabbits, and hamsters, or non-mammalian organisms such as birds, reptiles, and amphibians. In this embodiment, the pet sheet 1 is an absorbent sheet for cats. The pet sheet 1 is used by being placed, for example, on the floor or on the tray of a pet toilet system.

[0026] As shown in Figure 1, the pet sheet 1 is formed in a rectangular shape having a long side and a short side, as an example. For convenience, in this specification, the thickness direction of the pet sheet 1 is defined as the Z-axis direction, the longitudinal direction parallel to the long side of the pet sheet 1 is defined as the X-axis direction, and the short direction parallel to the short side of the pet sheet 1 is defined as the Y-axis direction. Hereinafter, each of the above directions will be represented in correspondence with the XYZ Cartesian coordinate system shown in the drawings, with the thickness direction (Z-axis direction) being referred to as "thickness direction Z", the longitudinal direction (X-axis direction, first direction) as "longitudinal direction X", and the short direction (Y-axis direction, second direction) as "short direction Y".

[0027] The pet sheet 1 has a surface sheet 10, a back sheet 20, and an absorbent material 30. The thickness direction Z mentioned above is the direction in which the surface sheet 10 and the back sheet 20 face each other.

[0028] The surface sheet 10 is positioned on the side where pet waste is supplied when the pet sheet 1 is in use. The surface sheet 10 has a surface 11 that is exposed outward (upward) when placed on the floor or on the tray of the system toilet, and an inner surface 12 on the opposite side of the surface 11.

[0029] For example, the surface sheet 10 may be made of a liquid-permeable sheet material so as to allow pet excrement supplied to the surface 11 to move to the back sheet 20 side (inner surface 12 side). For example, the sheet material constituting the surface sheet 10 is made of a nonwoven or woven fabric having white fibers. Examples of such sheet materials include air-through nonwoven fabric, spunbond nonwoven fabric, point-bond nonwoven fabric, etc.

[0030] The back sheet 20 is a sheet member positioned opposite the front sheet 10 in the thickness direction Z. For example, the back sheet 20 is formed in the same rectangular shape as the front sheet 10 so that it overlaps with the front sheet 10 when viewed from the thickness direction Z. The back sheet 20 has a back surface 21 that faces the floor surface or the surface on which the tray of a system toilet is placed when the pet sheet 1 is in use, and an inner surface 22 on the opposite side of the back surface 21.

[0031] As an example, the back sheet 20 may be made of a liquid-impermeable sheet material. Examples of sheet materials that make up the back sheet 20 include non-permeable resin films such as polyethylene and polypropylene, laminates made by laminating a nonwoven fabric to the resin film, and water-repellent or hydrophobic nonwoven fabrics. When the back sheet 20 is made of a liquid-impermeable sheet material in this way, it is possible to prevent excrement excreted on the pet sheet 1 from leaking onto the floor or the surface on which the tray is placed. However, the back sheet 20 may also be made of a liquid-permeable material. For example, when the pet sheet 1 is placed on another pet sheet (for example, an absorbent sheet with larger dimensions in plan view than the pet sheet 1), by making the back sheet 20 liquid-permeable, urine that cannot be absorbed by the pet sheet 1 can be transferred to the other pet sheet and absorbed.

[0032] The absorbent body 30 is positioned between the surface sheet 10 and the back sheet 20. As shown in Figure 1, the absorbent body 30 is formed in a rectangular shape that is slightly smaller than the main body (surface sheet 10 and back sheet 20) when viewed from the thickness direction Z, and is positioned in the central part of the main body excluding the peripheral edges. As shown in Figures 2 and 3, as an example, the absorbent body 30 is composed of an absorbent core 31 containing an absorbent material for absorbing and retaining excrement, and a core wrap 32 (cover sheet) that covers the absorbent core 31.

[0033] The core wrap 32 includes at least a portion that covers the surface of the absorbent core 31 (the surface facing the surface sheet 10). In this embodiment, the core wrap 32 covers the surface (the surface facing the surface sheet 10), the back surface (the surface facing the back sheet 20), and the sides (the surfaces facing the longitudinal direction X) of the absorbent core 31. As an example, the core wrap 32 has a surface cover portion 321 that covers the surface of the absorbent core 31, and a back cover portion 322 that covers the back surface and sides of the absorbent core 31. The core wrap 32 is made of, for example, a liquid-permeable tissue.

[0034] The surface cover portion 321 is positioned on the surface of the absorption core 31. In the longitudinal direction X, the back cover portion 322 is longer than the surface cover portion 321. As shown in Figure 3, in the short direction Y, the back cover portion 322 and the surface cover portion 321 have the same length. As shown in Figure 2, the back cover portion 322 has a pair of portions that protrude from the surface cover portion 321 on both sides in the longitudinal direction X, and these portions are folded back to cover the sides of the absorption core 31 and the edges of the surface cover portion 321 in the longitudinal direction X. Note that the above configuration is merely an example, and the core wrap 32 may be formed in a bag shape that continuously covers the surface, sides, and back of the absorption core 31, for example.

[0035] The absorbent core 31 comprises an upper pulp layer 311 (first pulp layer) containing pulp, an SAP layer 312 containing a superabsorbent polymer (SAP), an antibacterial agent 313, and a lower pulp layer 314 (second pulp layer) containing pulp.

[0036] The upper pulp layer 311 primarily functions to draw in liquid (such as urine) from the surface sheet 10. For example, the upper pulp layer 311 is composed solely of pulp and does not contain SAP.

[0037] The SAP layer 312 is positioned between the upper pulp layer 311 and the lower pulp layer 314. The SAP layer 312 allows the liquid to be quickly guided to the back sheet 20 side.

[0038] The antibacterial agent 313 (second antibacterial agent) is positioned on the back sheet 20 side of the upper pulp layer 311. The antibacterial agent 313 may be mixed with the SAP constituting the SAP layer 312, or it may be positioned primarily above the SAP layer 312 (on the upper pulp layer 311 side), or it may be positioned primarily below the SAP layer 312 (on the lower pulp layer 314 side). The antibacterial agent 313 may be an organic antibacterial agent such as a quaternary ammonium salt or a parahydroxybenzoic acid ester. Alternatively, the antibacterial agent may be an inorganic antibacterial agent containing inorganic substances such as Ag, Mn, Fe, Co, Ni, Cu, and Zn. In this embodiment, the antibacterial agent 313 is positioned (sprayed) between the upper pulp layer 311 and the lower pulp layer 314. The antibacterial function of the antibacterial agent 313 is exerted as the liquid guided from the upper pulp layer 311 to the lower pulp layer 314 passes through the antibacterial agent 313. This makes it possible to suppress the growth of bacteria in the liquid held in the pet sheet 1 (lower pulp layer 314, etc.).

[0039] The lower pulp layer 314 primarily functions to retain the liquid drawn in by the upper pulp layer 311. As an example, the lower pulp layer 314 contains pulp and an antimicrobial superabsorbent polymer (antimicrobial SAP314a) containing antimicrobial components.

[0040] The inner surface 12 of the surface sheet 10 may be joined to the sheet material facing the inner surface 12 (a part of the inner surface 22 of the back sheet 20 and the part of the core wrap 32 facing the inner surface 12) by an adhesive such as a hot melt adhesive. Alternatively, the inner surface 12 and the sheet material may be joined by methods other than adhesives, such as heat welding or ultrasonic welding.

[0041] The inner surface 22 of the back sheet 20 may be joined to the sheet material facing the inner surface 22 (a part of the inner surface 12 of the surface sheet 10 and the part of the core wrap 32 facing the inner surface 22) by an adhesive such as a hot melt adhesive. Alternatively, the inner surface 22 and the sheet material may be joined by methods other than adhesives, such as heat welding or ultrasonic welding.

[0042] The absorbent body 30 includes a wood member 40 (plant-derived member) disposed between the absorbent core 31 and the surface cover portion 321. The wood member 40 may include wood pieces having a particle size of several millimeters (mm) or more, or may include wood powder having a particle size of approximately several hundred microns (μm) to several millimeters (mm). Here, the "diameter (particle size)" of the wood piece or wood powder is, for example, the radius of the smallest circle that encloses one wood piece or wood powder when viewed from the thickness direction Z. As an example, the wood member 40 is constituted by finely pulverized wood pieces or wood powder in an unprocessed state that has not undergone processing such as removal of essential oil or moisture. Thereby, the wood member 40 is in a state containing active ingredients (deodorant components, antibacterial components, etc.) inherently possessed by the raw material wood. The wood serving as the material of the wood member 40 is, for example, cypress. However, the wood serving as the material of the wood member 40 is not limited to cypress. For example, the wood serving as the material of the wood member 40 may be a broadleaf tree such as those belonging to the Tectona genus of the Verbenaceae family, the Quercus genus of the Fagaceae family, the Fagus genus of the Fagaceae family, the Cinnamomum genus of the Lauraceae family, or the Betula genus of the Betulaceae family.

[0043] In the present embodiment, the wood member 40 is configured to include a plurality of wood powders. Figure 4 is an actual image showing an example of such a plurality of wood powders. Figure 4 shows wood powder obtained by pulverizing cypress.

[0044] When viewed from the thickness direction Z, the wood member 40 is unevenly distributed in one or more regions within the core region CA (see FIG. 1) that overlaps with the absorbent core 31. Here, "unevenly distributed in one or more regions" means an aspect that is different from an aspect in which the wood member (for example, a plurality of wood powders) is mixed into most of the core region CA (that is, an aspect in which the wood member is arranged substantially uniformly), and means an aspect in which a clearly larger amount of the wood member 40 is arranged in one or more specific regions than in other regions.

[0045] In the present embodiment, the wood member 40 disposed inside the absorber 30 (between the absorbent core 31 and the surface cover portion 321) is arranged in a plurality of (five as an example) linear regions A1 to A5. That is, a plurality of wood powders are spread all over the linear regions A1 to A5. The linear regions A1 to A5 have a predetermined width (about 5 mm as an example) in the longitudinal direction X, and extend in the lateral direction Y. In the present embodiment, the linear regions A1 to A5 extend from one end to the other end of the core region CA in the lateral direction Y.

[0046] As shown in Figure 1, the core region CA is formed in a rectangular shape (quadrilateral shape) having long sides (first sides) and short sides (second sides) perpendicular to each other when viewed from the thickness direction Z. Here, a center line CL that passes through the center of the core region CA in the longitudinal direction X parallel to the long sides and extends along the lateral direction Y parallel to the short sides is defined, and a first region R1 located on one side (the left side in the drawing as an example) in the longitudinal direction X relative to the center line CL in the core region CA, and a second region R2 located on the other side (the right side in the drawing as an example) in the longitudinal direction X relative to the center line CL in the core region CA are defined. The linear regions A1 and A2 are arranged in the first region R1, and the linear regions A4 and A5 are arranged in the second region R2. The linear region A3 is arranged along the center line CL. Since the linear region A3 has a predetermined width in the longitudinal direction X as described above, it has both a portion included in the first region R1 and a portion included in the second region R2.

[0047] The linear regions A1 and A2 are arranged at predetermined intervals in a region on the side (left side) farther from the center line CL than the central position of the first region R1 in the longitudinal direction X. The linear region A1 is arranged at a position farther from the center line CL than the linear region A2.

[0048] The linear regions A4 and A5 are arranged at predetermined intervals in a region on the side (right side) farther from the center line CL than the central position of the second region R2 in the longitudinal direction X. The linear region A5 is arranged at a position farther from the center line CL than the linear region A4.

[0049] Linear regions A1 and A2 are positioned symmetrically to linear regions A4 and A5 with respect to the center line CL. That is, when the pet sheet 1 is folded in half along the center line CL, linear regions A1 and A2 are positioned to overlap with linear regions A4 and A5.

[0050] In the pet sheet 1, fragrance 50 may be provided on at least a portion of the overlapping area with the wood member 40 in the thickness direction Z of at least one of the surface sheet 10 and the absorbent 30. In this embodiment, as an example, the fragrance 50 is provided on the surface 11 of the surface sheet 10 in the portion that overlaps with the linear regions A1 to A5 in the longitudinal direction X (including the portion outside the linear regions A1 to A5 in the short direction Y where the absorbent 30 is not provided). The fragrance 50 is, for example, cypress fragrance. The fragrance 50 is provided on the surface 11 of the surface sheet 10 by being applied or sprayed onto the surface 11 of the surface sheet 10 by a coater or the like during the manufacturing process of the pet sheet 1.

[0051] In the pet sheet 1 described above, by arranging the wood material 40 so that it is unevenly distributed within the core region CA on the surface side of the absorbent core 31 (in this embodiment, between the surface cover portion 321 and the upper pulp layer 311), the visibility (presence) of the wood material 40 when viewed from the surface sheet 10 side can be enhanced. This makes the user aware of the presence of the wood material 40 and gives them a sense of woody scent and atmosphere, thereby giving them confidence in the quality of the pet sheet 1 (for example, the impression that the wood provides a deodorizing effect). Furthermore, since the wood material 40 is provided independently of the absorbent core 31 and between the absorbent core 31 (upper pulp layer 311) and the surface cover portion 321, it is possible to suppress the wood material 40 from hindering the performance of the absorbent core 31 itself (for example, liquid diffusion). Furthermore, as described above, the wood-based material 40 is arranged to be unevenly distributed within the core area CA and is not uniformly distributed throughout the entire core area CA. Therefore, the color of the pet's urine can be easily determined by the change in color in the areas within the core area CA where the wood-based material 40 is not present. Thus, the pet sheet 1 can give users confidence in its quality (for example, the antibacterial and deodorizing functions of the wood-based material 40) without compromising usability.

[0052] The wood-based member 40 has multiple wood powders. As shown in Figure 1, the multiple wood powders are arranged in at least one linear region (in this embodiment, five linear regions A1 to A5) that extends linearly when viewed from the thickness direction Z. With the above configuration, it becomes easy to clearly distinguish and recognize the linear regions A1 to A5 in which the wood-based member 40 is arranged from the regions in which the wood-based member 40 is not arranged. This allows the user to effectively visually confirm the presence of the wood-based member 40 (multiple wood powders), and also enables suitable health checks of pets based on color changes (pet urine color) in the regions in which the wood-based member 40 is not arranged.

[0053] At least one linear region constituting the wood-based member 40 includes a plurality of linear regions A1 to A5. With this configuration, by providing a plurality of regions in which a plurality of wood powders are arranged linearly, the presence of the wood-based member 40 (a plurality of wood powders) can be more effectively visually perceived by the user.

[0054] The core region CA is formed in a rectangular shape with mutually perpendicular long and short sides when viewed from the thickness direction Z. At least one linear region includes linear regions A1 and A2 (first linear region) located in the first region R1 to the left of the center line CL within the core region CA, and linear regions A4 and A5 (second linear region) located in the second region R2 to the right of the center line CL within the core region CA. Note that linear region A3, provided along the center line CL, has a portion that overlaps with both the first region R1 and the second region R2, and therefore corresponds to both the first and second linear regions described above. According to the above configuration, by arranging multiple linear regions A1 to A5 in regions on both sides of the center line CL (first region R1 and second region R2), when a pet defecates in a location biased towards either the first region R1 side or the second region R2 side of the center line CL, the deodorizing effect of the wood material 40 (multiple wood powders) can be suitably obtained regardless of which region the pet defecates in.

[0055] At least one linear region includes a linear region A3 that extends in the short direction Y such that it overlaps with the center line CL when viewed from the thickness direction Z. With the above configuration, when a pet defecates in the central part of the pet sheet 1 (the part along the center line CL), a deodorizing effect can be suitably obtained from the wood material 40 (multiple wood powders).

[0056] At least one linear region includes two linear regions A2 and A3 that are separated from each other in the longitudinal direction X and extend in the transverse direction Y. As shown in Figure 1, the distance G1 between the two linear regions A2 and A3 in the longitudinal direction X is 1 / 5 or more of the length L of the absorbing core 31 (i.e., core region CA) in the longitudinal direction X. With the above configuration, by securing a region with a sufficiently large area between the two linear regions A2 and A3 where no wooden member 40 is placed, it becomes possible to perform the pet health check based on urine color described above even more effectively.

[0057] At least one linear region includes two linear regions A2 and A3 in the first region R1, and two linear regions A3 and A4 in the second region R2. Furthermore, since the first region R1 and the second region R2 are configured symmetrically with respect to the center line CL, the spacing G2 between linear regions A3 and A4 is also at least 1 / 5 of the length L of the core region CA, similar to the spacing G1 between linear regions A2 and A3. With the above configuration, a sufficiently large area without any wooden members 40 can be secured in each of the first region R1 and the second region R2. For example, when a pet urinates in the second region R2 to avoid its own urine trail after initially urinating in the first region R1, it becomes possible to suitably perform the pet's health check based on urine color in both the first region R1 and the second region R2.

[0058] Fragrance 50 is provided in at least a portion of the area that overlaps with the wood member 40 in the thickness direction Z of at least one of the surface sheet 10 and absorbent body 30. As described above, in this embodiment, fragrance 50 is provided in the area of ​​the surface 11 of the surface sheet 10 that overlaps with the linear areas A1 to A5 in the longitudinal direction X. With the above configuration, by providing fragrance 50 in a location that overlaps with the wood member 40 in the thickness direction Z, it is possible to give the user the impression that the scent of fragrance 50 is being emitted by the wood member 40. This makes it easy for the user to recognize the presence of the wood member 40 and improves the user's confidence in the quality. Note that the fragrance 50 only needs to overlap with at least a portion of the area that overlaps with the wood member 40, and does not need to overlap with the entire linear areas A1 to A5 as in this embodiment. Furthermore, fragrance 50 may also be provided in the area of ​​the core area CA where the wood member 40 is not provided (i.e., the area of ​​the core area CA that does not overlap with the linear areas A1 to A5). Furthermore, the fragrance 50 may be provided on the inner surface 12 of the surface sheet 10, or on the absorbent 30 (for example, the surface cover portion 321). However, from the viewpoint of suitably obtaining the above effects, it is preferable that the fragrance 50 be provided on the surface 11 of the surface sheet 10 that is exposed to the outside during use, as in this embodiment.

[0059] The wood-based member 40 has multiple wood powders (see Figure 4), and the surface cover portion 321 is made of tissue. In this embodiment, not only the surface cover portion 321 but also the back cover portion 322 is made of tissue. With the above configuration, it is possible to suppress the wood powder constituting the wood-based member 40 from passing through the surface cover portion 321 and being discharged to the outside of the absorbent 30.

[0060] When viewed from the thickness direction Z, the area where the wood material 40 is placed (in this embodiment, the total area of ​​linear regions A1 to A5) is less than 30% of the total area of ​​the core region CA. With the above configuration, by ensuring a sufficient area where the wood material 40 is not placed (i.e., an area where the wood material 40 does not have a color and where it is easy to grasp the color change due to the pet's urine), it becomes possible to perform the above-mentioned health check of the pet based on urine color more effectively. From the viewpoint of performing such a health check effectively, it is more preferable that the above ratio be less than 20%. For example, if the length L in the longitudinal direction X of the core region CA is 390 mm and the width in the longitudinal direction X of each of the linear regions A1 to A5 is 5 mm, then the above ratio is 6.4%.

[0061] The wood-based member 40 contains multiple wood powders or wood chips. Furthermore, the average area of ​​each individual wood-based member 40 when viewed from the thickness direction Z is 64 mm². ２The following applies. The average area of ​​the wood-based member 40 may be calculated, for example, as follows. First, in the region where the wood-based member 40 is arranged (for example, a region of a predetermined area or larger arbitrarily extracted from the linear regions A1 to A5), the surface cover portion 321 is peeled off, and the upper pulp layer 311 and the wood-based member 40 provided on the upper pulp layer 311 are imaged from a position facing the upper pulp layer 311 in the thickness direction Z. By analyzing the imaged image (for example, an image like the one shown in Figure 4), portions with a diameter of several hundred μm or more (a single wood powder or wood chip) are individually detected, and the average area of ​​the multiple detected lumps is calculated. If the size of individual wood powders cannot be determined in their original state, such as when multiple wood powders (wood-based members 40) are densely packed together, the image taken after partially collecting the upper pulp layer 311 and the wood-based member 40 provided on the upper pulp layer 311 and moving them to another location may be used as the image subject to the above image analysis.

[0062] According to the above configuration, by making the size of the individual elements (wood powder or wood chips) that make up the wood component 40 relatively small, the overall surface area of ​​the wood component 40 can be made relatively large. As a result, when the wood component 40 gets wet with pet urine, the distinctive scent of wood is more easily released. Consequently, the unpleasantness caused by the smell of urine can be reduced.

[0063] As shown in Figure 1, the arrangement of the wooden members 40 in the first region R1 and the arrangement of the wooden members 40 in the second region R2 are symmetrical with respect to the center line CL. For example, when using the pet sheet 1 in a dedicated tray, there may be a predetermined location where the pet prefers to urinate. With the symmetrical configuration described above, after the pet first urinates in the first region R1, the orientation of the tray can be reversed so that the first region R1 and the second region R2 are swapped, making it possible to have the pet urinate in the second region R2. In this case, because the arrangement of the wooden members 40 in the first region R1 and the arrangement of the wooden members 40 in the second region R2 are symmetrical with respect to the center line CL, the arrangement of the wooden members 40 in the pet sheet 1 does not change before and after the orientation of the tray is changed. This makes it possible to utilize both the first region R1 and the second region R2 without causing discomfort to the pet.

[0064] As shown in Figure 1, the PET sheet 1 (surface sheet 10, back sheet 20, and absorbent core 31) has fold lines FL (creases) formed on it for folding the PET sheet 1. In the example in Figure 1, two fold lines FL for folding the PET sheet 1 into thirds are provided on both sides of the center line CL in the longitudinal direction X. For example, the fold line FL formed in the first region R1 is located in the region between linear regions A2 and A3, and the fold line FL formed in the second region R2 is located in the region between linear regions A3 and A4. The wood member 40 is arranged so as not to overlap with the fold lines FL when viewed from the thickness direction Z. With the above configuration, when the PET sheet 1 is folded along the fold lines FL, the risk of the wood member 40 flying out or being ejected from the portion of the fold line FL due to pressure applied to the fold line FL can be reduced.

[0065] The wood-based material 40 may contain antibacterial components and may function as an antibacterial agent. That is, in the pet sheet 1, in addition to the antibacterial agent 313 (second antibacterial agent) placed downstream of the upper pulp layer 311 (on the back sheet 20 side), another antibacterial agent (first antibacterial agent) (wood-based material 40 in this embodiment) is placed upstream of the upper pulp layer 311. As a result, not only the antibacterial performance of the antibacterial agent 313 that acts on urine after it has passed through the upper pulp layer 311, but also the antibacterial performance against urine before it penetrates the upper pulp layer 311 can be obtained by the first antibacterial agent (wood-based material 40). Furthermore, since the first antibacterial agent (wood-based material 40) is placed inside the absorbent body 30 (between the surface cover portion 321 and the absorbent core 31) rather than outside the absorbent body 30, contact between the first antibacterial agent (wood-based material 40) and the pet's skin (paws, etc.) on the surface sheet 10 is suppressed. Therefore, the pet sheet 1 can improve antibacterial performance while reducing irritation to the pet's skin.

[0066] The first antibacterial agent comprises multiple powders (multiple wood powders in this embodiment), and the surface cover portion 321 is made of tissue. With the above configuration, by using a powdered first antibacterial agent (multiple wood powders), the surface area of ​​the first antibacterial agent can be increased, and the antibacterial performance of the first antibacterial agent can be suitably exhibited. Furthermore, by making the surface cover portion 321 out of tissue, it is possible to prevent the powdered first antibacterial agent from slipping through the surface cover portion 321 and being discharged to the outside of the absorbent body 30.

[0067] The multiple wood powders (woody components 40) constituting the first antibacterial agent include wood powders having a fiber length longer than the fiber length of the pulp contained in the upper pulp layer 311. The average fiber length of the pulp contained in the upper pulp layer 311 may be, for example, about 1 mm to 2 mm, and the woody components 40 (multiple wood powders) may include wood powders with a larger fiber length (for example, about 3 to 5 mm). With the above configuration, the first antibacterial agent (woody components 40) can be suitably maintained on the surface layer (surface cover portion 321 side) of the upper pulp layer 311, so that the antibacterial function against urine before it penetrates the upper pulp layer 311 can be suitably exhibited.

[0068] It is preferable that the antibacterial activity value of the first antibacterial agent (wood component 40) is lower than that of the second antibacterial agent (antibacterial agent 313). With the above configuration, even if the first antibacterial agent, which is close to the pet's skin (i.e., located on the surface sheet 10 side), comes into contact with the pet's skin, the antibacterial power (antibacterial activity value) of the first antibacterial agent is weaker than that of the second antibacterial agent, thus reducing irritation to the pet's skin. The antibacterial activity value of the wood component 40 can be measured, for example, by conducting an antibacterial test in accordance with JIS L 1902:2015 "Antibacterial Test Method and Antibacterial Effect of Textile Products" (Reference: Microbial Resistance of Amur Cork Tree Wood, Yoko Kiyokawa, Atsuko Sakai, Yoriko Iwamoto, Masao Tsuzuki, Nara Prefectural Forestry Technology Research Center Report No. 50 (2021)).

[0069] The absorbent core 31 further has a lower pulp layer 314 positioned on the back sheet 20 side of the upper pulp layer 311. The lower pulp layer 314 contains pulp and a superabsorbent polymer (antibacterial SAP314a). The "second antibacterial agent positioned on the back sheet 20 side of the upper pulp layer 311" includes an antibacterial agent 313 positioned between the upper pulp layer 311 and the lower pulp layer 314. With the above configuration, urine is diffused by the upper pulp layer 311, the antibacterial agent 313 (second antibacterial agent) positioned between the upper pulp layer 311 and the lower pulp layer 314 exhibits suitable antibacterial performance against urine, and finally, the superabsorbent polymer (antibacterial SAP314a) provided in the lower pulp layer 314 can effectively absorb the urine.

[0070] The basis weight of the pulp in the upper pulp layer 311 is greater than the basis weight of the pulp in the lower pulp layer 314. For example, the basis weight of the pulp in the upper pulp layer 311 is 100 gm. －２ The pulp weight of the lower pulp layer 314 is set to approximately 40 gm －２ It can be set to a certain extent. With the above configuration, by making the basis weight of the upper pulp layer 311 relatively large, the liquid diffusion performance of urine in the upper pulp layer 311 can be improved. This makes it possible to improve the urine absorption performance of the lower pulp layer 314 (superabsorbent polymer (antibacterial SAP314a)) in the subsequent stage.

[0071] The superabsorbent polymer (antibacterial SAP314a) contained in the lower pulp layer 314 has antibacterial properties. Furthermore, the "second antibacterial agent positioned on the back sheet 20 side of the upper pulp layer 311" is composed of an antibacterial agent 313 positioned between the upper pulp layer 311 and the lower pulp layer 314, and the superabsorbent polymer (antibacterial SAP314a) contained in the lower pulp layer 314. With the above configuration, by providing the second antibacterial agent between the upper pulp layer 311 and the lower pulp layer 314, and also providing it inside the lower pulp layer 314 in the subsequent stage, the antibacterial performance against urine after it has passed through the upper pulp layer 311 can be suitably exhibited.

[0072] While embodiments of this disclosure have been described above, this disclosure is not limited to the embodiments described above. Various materials and shapes can be used for the materials and shapes of each component, not limited to those described above. Furthermore, some of the components included in the embodiments described above may be modified or omitted, or other components may be added.

[0073] In the above embodiment, the pet sheet 1 is formed in a rectangular shape when viewed from the thickness direction Z, but the shape of the pet sheet 1 in plan view is not limited to a rectangle and may be any shape other than a quadrilateral, such as a polygon, circle, or ellipse. Also, the size of the pet sheet 1 can be appropriately set according to the size and type of pet to which the pet sheet 1 is applied. Similarly, the shape of the core area CA when viewed from the thickness direction Z is not limited to a rectangle and may be any shape other than a quadrilateral, such as a polygon, circle, or ellipse.

[0074] In the above embodiment, the wooden member 40 was provided in multiple linear regions A1 to A5, but the wooden member 40 may be placed in a single linear region. Also, the number of multiple linear regions is not limited to five; it may be four or fewer, or six or more. Furthermore, in the above embodiment, the linear regions A1 to A5 extended parallel to the short direction Y, but the wooden member 40 may be placed in a linear region extending in the longitudinal direction X, or in a linear region extending in an oblique direction inclined in both the longitudinal direction X and the short direction Y. In addition, the wooden member 40 may be placed in a region with a shape other than a linear shape.

[0075] In the above embodiment, the wood-based member 40 was composed of a plurality of wood powders, but the wood-based member 40 may also contain relatively large pieces of wood. Furthermore, from the viewpoint of obtaining the effect of the first antibacterial agent described above, the first antibacterial agent does not necessarily have to be composed of the wood-based member 40, and the first antibacterial agent may be composed of a material other than wood that has antibacterial properties. The first antibacterial agent may be, for example, activated carbon with antibacterial properties (e.g., Ag catalyst activated carbon), or a plant-derived material other than a wood-based member, such as tea leaves or dried flowers.

[0076] In the above embodiment, the absorbent core 31 had a two-layer structure including an upper pulp layer 311 and a lower pulp layer 314, but it may also have a single-layer structure. For example, the absorbent core 31 does not need to include the lower pulp layer 314. In this case, the upper pulp layer 311 may contain antibacterial SAP 314a.

[0077] In the above embodiment, the basis weight of the pulp in the upper pulp layer 311 was greater than that of the pulp in the lower pulp layer 314, but it may be the same as or less than that of the pulp in the lower pulp layer 314.

[0078] 1... Pet sheet (absorbent sheet), 10... Surface sheet, 20... Back sheet, 30... Absorbent material, 31... Absorbent core, 32... Core wrap (cover sheet), 40... Wood material (first antibacterial agent), 311... Upper pulp layer (first pulp layer), 313... Antibacterial agent (second antibacterial agent), 314... Lower pulp layer (second pulp layer), 321... Surface cover part, 314a... Antibacterial SAP.

Claims

1. An absorbent sheet for pets comprising: a liquid-permeable surface sheet; a back sheet disposed opposite the surface sheet; and an absorbent body disposed between the surface sheet and the back sheet, wherein the absorbent body comprises an absorbent core; a cover sheet including a surface cover portion that covers the surface side of the absorbent core; and a first antibacterial agent disposed between the absorbent core and the surface cover portion, and the absorbent core comprises a first pulp layer containing pulp and a second antibacterial agent disposed on the back sheet side of the first pulp layer.

2. The absorbent sheet according to claim 1, wherein the first antibacterial agent comprises a plurality of powders, and the surface cover portion is tissue.

3. The absorbent sheet according to claim 1, wherein the antibacterial activity value of the first antibacterial agent is lower than the antibacterial activity value of the second antibacterial agent.

4. The absorbent sheet according to claim 1, wherein the first antibacterial agent comprises a plurality of wood powders, and the plurality of wood powders include wood powders having a fiber length longer than the fiber length of the pulp contained in the first pulp layer.

5. The absorbent sheet according to claim 1, wherein the absorbent core further comprises a second pulp layer disposed on the back sheet side of the first pulp layer, the second pulp layer comprises pulp and a superabsorbent polymer, and the second antimicrobial agent comprises an antimicrobial agent disposed between the first pulp layer and the second pulp layer.

6. The absorbent sheet according to claim 5, wherein the basis weight of the pulp contained in the first pulp layer is greater than the basis weight of the pulp contained in the second pulp layer.

7. The absorbent sheet according to claim 5 or 6, wherein the superabsorbent polymer contained in the second pulp layer has antibacterial properties, and the second antibacterial agent comprises the antibacterial agent disposed between the first pulp layer and the second pulp layer, and the superabsorbent polymer contained in the second pulp layer.

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