Absorbent article

Abstract

The present invention provides an absorbent article having an absorbent body (3) and a topsheet (2) disposed on the skin-facing side of the absorbent body (3), the topsheet (2) having an upper layer (21) and a lower layer (22) located on the non-skin-facing side of the upper layer (21), the upper layer (21) containing a first antibacterial agent, the absorbent body (3) containing a second antibacterial agent, the first antibacterial agent being an antibacterial agent having lower solubility in water than the second antibacterial agent. The difference in solubility between the first antibacterial agent and the second antibacterial agent is preferably 0.5 g / 100 ml or more.

Description

Technical Field

[0001] This invention relates to absorbent articles. Background Technology

[0002] In the prior art, antibacterial agents are incorporated into the top sheet of absorbent articles for the purpose of preventing rashes. For example, Patent Document 1 describes an absorbent article having a top sheet and a liquid-permeable sheet disposed in contact with the non-skin side of the top sheet, wherein the top sheet and the liquid-permeable sheet contain an antibacterial agent. Benzalkonium chloride, etc., is used as the antibacterial agent.

[0003] Patent Document 2 describes an absorbent article whose top sheet is made of a nonwoven fabric composed of composite fibers having a core and a sheath, and that only the sheath contains a micro-powder powder that prevents skin roughness, with a portion of the micro-powder powder exposed on the surface of the fibers. Zinc oxide or similar materials are used as the micro-powder powder.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2017-6505

[0007] Patent Document 2: Japanese Patent Application Publication No. 2006-55187 Summary of the Invention

[0008] This invention relates to an absorbent article.

[0009] The aforementioned absorbent article preferably has an absorbent body and a top sheet disposed on the skin-facing side of the absorbent body.

[0010] The aforementioned top sheet preferably has an upper layer and a lower layer located on the non-skin-facing side of the upper layer.

[0011] The upper layer preferably contains a first antibacterial agent. The absorbent preferably contains a second antibacterial agent.

[0012] The first antibacterial agent is preferably an antibacterial agent with lower solubility in water than the second antibacterial agent. Attached Figure Description

[0013] Figure 1 This is a schematic cross-sectional view in the width direction of one embodiment of the absorbent article of the present invention. Detailed Implementation

[0014] In the absorbent article of Patent Document 1, since the antibacterial agent applied to the top sheet is a water-miscible substance, the antibacterial agent mixes with water through urination, and the mixed antibacterial agent is transferred to the absorbent core, resulting in a reduction in the amount of antibacterial agent contained in the top sheet. When feces easily adhere to the top sheet, the reduced amount of antibacterial agent decreases the antibacterial effect against feces. As a result, rashes are more likely to occur due to feces adhering to the top sheet.

[0015] While patent document 2 describes antibacterial measures for the top sheet, it lacks research on how to ensure the antibacterial effect is achieved within the absorbent core. Therefore, in the absorbent article of this document, bacteria may multiply within the absorbent core after it absorbs urine, potentially leading to a foul odor.

[0016] As such, in the absorbent articles of Patent Documents 1 and 2, it is difficult to maintain an antibacterial effect for a long time.

[0017] Therefore, the present invention relates to absorbent articles that can eliminate the disadvantages present in the prior art.

[0018] Hereinafter, the preferred embodiments of the present invention will be described with reference to the accompanying drawings.

[0019] The absorbent article of the present invention is generally formed in an elongated shape, having a length direction corresponding to a direction extending from the wearer's abdomen through the crotch to the back, and a width direction orthogonal to therein. Furthermore, the absorbent article has a crotch portion disposed in the wearer's crotch, and abdominal and back portions extending forward and backward therefrom. The crotch portion has an excretory portion opposing the wearer's excretory portion when the absorbent article is worn, which is generally located at or near the center of the absorbent article in its length direction.

[0020] Figure 1 The diagram illustrates one embodiment of the absorbent article of the present invention. Figure 1 The absorbent article 1 shown in the figure has an absorbent body 3, a top sheet 2 disposed on the skin-facing side of the absorbent body 3, and a back sheet 4 disposed on the non-skin-facing side of the absorbent body 3.

[0021] When referring to absorbent articles or their constituent parts (such as absorbent bodies), "skin-facing side" refers to the side of the absorbent article that faces the wearer's skin when worn, and "non-skin-facing side" refers to the side of the absorbent article that faces the opposite side to the wearer's skin when worn. In addition, "when wearing" and "wearing state" refer to the state in which the absorbent article is worn to maintain the proper wearing position.

[0022] Top sheet 2 covers the skin-facing side of absorber 3. Top sheet 2 may cover only a portion of the skin-facing side of absorber 3, or it may cover the entire skin-facing side of absorber 3.

[0023] As the top sheet 2, materials such as hydrophilic, liquid-permeable sheets, nonwoven fabrics, or perforated membranes can also be used. The skin-facing side of the top sheet 2 can also have an uneven shape. For example, multiple protrusions can be formed in a scattered pattern on the skin-facing side of the top sheet 2. Alternatively, ridges and grooves extending in one direction can be alternately formed on the skin-facing side of the top sheet 2. For this purpose, two nonwoven fabrics can also be used to form the top sheet 2.

[0024] The back sheet 4 covers the non-skin-facing side of the absorber 3. The back sheet 4 may cover only a portion of the non-skin-facing side of the absorber 3, or it may cover the entire non-skin-facing side of the absorber 3.

[0025] As the backing sheet 4, materials such as liquid-impermeable membranes and liquid-impermeable spunbond-meltblown-spunbond laminated nonwoven fabrics can be used. Multiple micropores can be provided in the liquid-impermeable membrane to impart water vapor permeability. To improve the skin feel of absorbent materials, a sheet with a good hand feel, such as a nonwoven fabric, can be laminated onto the outer surface of the backing sheet 4.

[0026] The absorbent 3 has an absorbent core 32 and a coating chip 31 covering the absorbent core 32. Preferably, at least the skin-facing side of the absorbent core 32 is covered by the coating chip 31, and more preferably, the entire area of ​​the surface, including the skin-facing side and the non-skin-facing side, is covered by the coating chip.

[0027] The absorbent core 32 is composed of, for example, a fibrous mass of hydrophilic fibers such as cellulose (represented by pulp), a mixed fibrous mass of the hydrophilic fibers and the absorbent polymer, an accumulation of the absorbent polymer, and a laminated structure in which the absorbent polymer is carried between two absorbent sheets.

[0028] The chip 31 has an upper chip 31a covering the skin-facing side of the absorbent core 32 and a lower chip 31b covering the non-skin-facing side of the absorbent core 32. The upper chip 31a and the lower chip 31b can be a single piece or separate pieces.

[0029] As a packaging chip 31, for example, thin paper made of hydrophilic fibers, non-woven fabric with liquid permeability, etc. can be used.

[0030] In addition to the top sheet 2, back sheet 4, and absorbent body 3 described above, depending on the specific application of the absorbent article 1, leak-proof flaps (not shown) extending along the length direction may sometimes be provided on both sides of the skin-facing side. The leak-proof flaps typically have a base end and a free end. The leak-proof flaps have a base end on the skin-facing side of the absorbent article 1 and stand upright from the skin-facing side. The leak-proof flaps are made of a liquid-repellent or water-repellent and breathable material. An elastic member, including a nylon or similar material, may be provided in an elongated state at or near the free end of the leak-proof flap. When the absorbent article 1 is worn, this elastic member contracts, thereby causing the leak-proof flaps to stand upright towards the wearer's body, effectively preventing liquid excreted onto the top sheet 2 from spreading on the top sheet 2 and leaking outwards in the width direction of the absorbent article 1.

[0031] The absorbent article 1 may further have an adhesive layer on the surface other than the skin-facing side. The adhesive layer is used to secure the absorbent article 1 to underwear or other absorbent articles when it is worn.

[0032] Examples of absorbent articles 1 having the above-mentioned components include, but are not limited to, unfoldable disposable diapers, shorts-type disposable diapers, sanitary napkins, and mild incontinence pads.

[0033] The absorbent article 1 of this embodiment contains two different types of antimicrobial agents. The two antimicrobial agents are distinguished based on their different solubilities in water. In the following description, the antimicrobial agent with lower solubility in water will be referred to as the "first antimicrobial agent," and the antimicrobial agent with higher solubility in water will be referred to as the "second antimicrobial agent." The first and second antimicrobial agents are located in different positions within the absorbent article 1. The location and type of each antimicrobial agent will be described in detail below.

[0034] The first antibacterial agent is preferably contained in the top sheet 2. Particularly preferred is that the top sheet 2 is composed of an upper layer 21 and a lower layer 22 located on the non-skin-facing side of the upper layer 21, such that the first antibacterial agent is contained in the upper layer 21. The upper layer 21 and the lower layer 22 can be as follows: Figure 1 As shown, they are adjacent, or there may be one or more other layers between the two layers 21 and 22.

[0035] The first antibacterial agent may be contained throughout the entire area of ​​the upper layer 21, or it may be contained only in a portion of the upper layer 21. Particularly preferred is that the first antibacterial agent is contained at least in the portion opposite the excretion portion of the upper layer 21. Furthermore, the first antibacterial agent may be disposed in a dispersed form in the upper layer 21, or it may be disposed in multiple strips extending along the length direction.

[0036] On the other hand, the second antimicrobial agent is preferably contained in the absorbent 3. The second antimicrobial agent may be contained throughout the entire area of ​​the absorbent 3, or it may be contained only in a portion of the absorbent 3. In this embodiment, when the absorbent 3 has an absorbent core 32 and a ply 31, the second antimicrobial agent may be contained only in either the absorbent core 32 or the ply 31, preferably at least in the ply 31, and more preferably in both the absorbent core 32 and the ply 31.

[0037] By configuring the first and second antibacterial agents as described above, the first antibacterial agent exerts its antibacterial effect in the top sheet 2, and the second antibacterial agent exerts its antibacterial effect in the core 31 and the absorbent core 32. This is explained in detail because the top sheet 2 contains a first antibacterial agent with relatively low water solubility, so even if urine excreted by the wearer comes into contact with the top sheet 2, the first antibacterial agent is unlikely to dissolve from the top sheet 2, preventing its transfer from the top sheet 2 to the absorbent core 32. Therefore, the reduction of the first antibacterial agent content in the top sheet 2 can be prevented, thereby providing long-term protection against fecal rashes in the top sheet 2. On the other hand, because the absorbent body 3 contains a second antibacterial agent with relatively high water solubility, when urine excreted by the wearer reaches the absorbent body 3, the second antibacterial agent dissolves from the absorbent body 3 into the urine and easily transfers to the absorbent core 32 along with the urine. In this way, the second antibacterial agent can be retained within the absorbent core 32 by urination, thus preventing the proliferation of bacteria caused by urine within the absorbent core 32 for a prolonged period. As described above, the absorbent article 1 according to this embodiment can prevent rashes caused by feces and the proliferation of bacteria in the absorbent core for a prolonged period.

[0038] From the viewpoint of making the above effects more significant, it is preferable that the first antibacterial agent is present only in the top sheet 2, and that the other components of the absorbent article 1, represented by the absorbent body 3, do not contain the first antibacterial agent. On the other hand, it is preferable that the second antibacterial agent is present only in the packaging chip 31, and that the other components of the absorbent article 1, represented by the top sheet 2, do not contain the second antibacterial agent.

[0039] The solubility of each antibacterial agent in water can be compared based on the solubility measured by the following methods.

[0040] <Methods for measuring the solubility of antibacterial agents>

[0041] Add 5g of antibacterial agent to 100ml of water and stir at 300rpm for 30 minutes at room temperature (25℃). Additionally, measure the mass of the filter paper and use this measured mass as the initial mass of the filter paper.

[0042] The stirred solution was filtered using filter paper whose mass was measured, and the filter paper was then dried in a dryer at 40°C for 2 hours. The mass of the dried filter paper was measured and taken as the dried mass of the filter paper. The solubility was then calculated using the following formula.

[0043] Solubility (g) = 5 (g) - {(mass of dried filter paper) (g) - (initial mass of filter paper) (g)}

[0044] The higher the calculated solubility, the greater the solubility in water; the lower the solubility, the less solubility in water.

[0045] From the viewpoint of making the effect of preventing fecal rashes and bacterial growth in the absorbent core more significant over a long period, the difference in solubility between the first antibacterial agent and the second antibacterial agent is preferably 0.5 g / 100 ml or more, more preferably 1 g / 100 ml or more, and even more preferably 2 g / 100 ml or more. The upper limit of the difference in solubility between the first antibacterial agent and the second antibacterial agent can be set, for example, to 10 g / 100 ml or less.

[0046] From the viewpoint of making the effect of preventing the growth of bacteria in the absorbent core more significant over a long period of time, the solubility of the second antibacterial agent is preferably 1g / 100ml or more and 10g / 100ml or less, more preferably 2g / 100ml or more and 8g / 100ml or less, and even more preferably 4g / 100ml or more and 6g / 100ml or less.

[0047] From the viewpoint of making the long-term prevention of rashes caused by feces more significant, the solubility of the first antibacterial agent is preferably 0.01g / 100ml or more and 0.5g / 100ml or less, more preferably 0.03g / 100ml or more and 0.3g / 100ml or less, and even more preferably 0.05g / 100ml or more and 0.2g / 100ml or less.

[0048] The first antibacterial agent preferably contains a metal oxide. Metal oxides have low solubility in water, so even when in contact with urine, they are difficult to dissolve into the urine, thus having the advantage of easily remaining on the top plate 2. Examples of metal oxides include zinc oxide, silver oxide, aluminum oxide, titanium oxide, calcium oxide, and magnesium oxide. These metal oxides can be used alone or in combination of two or more. Among them, considering higher antibacterial activity, the first antibacterial agent preferably contains zinc oxide.

[0049] When the first antibacterial agent is a metal oxide, its particle size is appropriately determined from the perspective of the fineness of the fibers constituting the upper layer 21 and the ease with which the metal oxide is incorporated into the fibers. Typically, the average particle size of the aforementioned metal oxide is the volumetric particle size D at 50% capacity based on a laser diffraction scattering particle size distribution method. 50 This indicates a size between 1.5μm and 7μm.

[0050] The first antibacterial agent is preferably a substance soluble in a protein-containing solution. Because feces contain protein, by making the first antibacterial agent soluble in a protein-containing solution, the first antibacterial agent can easily transfer to the feces adhering to the top plate 2, thus more effectively preventing rashes. As used in this specification, "protein" can include, for example, digestive enzymes contained in feces.

[0051] Whether a first antimicrobial agent is soluble in a protein-containing solution can be confirmed by comparing the solubility of the first antimicrobial agent in a solution containing bovine serum albumin (BSA), a model protein, dissolved in phosphate-buffered saline (PBS) (hereinafter referred to as "standard solubility") with the solubility of the first antimicrobial agent in PBS without dissolved BSA (hereinafter referred to as "reference solubility"). Specifically, if the standard solubility is greater than or equal to the reference solubility, it can be determined that the first antimicrobial agent is soluble in the protein-containing solution. The method for measuring solubility is as described above.

[0052] The first antibacterial agent is preferably incorporated into the fibers constituting the upper layer 21. Therefore, even if the first antibacterial agent comes into contact with urine, it is difficult for it to detach from the upper layer 21. When the first antibacterial agent is incorporated into the fibers constituting the upper layer 21, the first antibacterial agent may be entirely present within the fiber, or a portion of the first antibacterial agent may be exposed on the surface of the fiber. When the fibers constituting the upper layer 21 are core-sheath type composite fibers, the first antibacterial agent may be contained only in either the core or the sheath of the fiber, or it may be contained in both the core and the sheath.

[0053] The top sheet 2 is formed as a two-layer structure with an upper layer 21 and a lower layer 22. The reason for including the first antibacterial agent in the upper layer 21 is that, since the upper layer 21 is in direct contact with the wearer's skin, including the first antibacterial agent in the upper layer 21 can effectively suppress skin rashes caused by feces. Therefore, the presence of the first antibacterial agent in the upper layer 21 does not preclude the presence of the first antibacterial agent in the lower layer 22. That is, the first antibacterial agent can be contained in the entire top sheet 2. However, the first antibacterial agent contained in the lower layer 22 does not contribute much to the suppression of rashes, and the amount of antibacterial agent used is more than that used when the first antibacterial agent is contained only in the upper layer 21, which is uneconomical. In addition, by having an antibacterial agent-free layer between the upper layer 21 and the core 31, it is possible to prevent urine temporarily absorbed by the absorbent core 32 from returning to the top sheet 2 side. Therefore, in the top layer 2, it is preferable that only the upper layer 21 contains the first antibacterial agent, while the lower layer 22 is substantially free of the first antibacterial agent. "Substantially free of" means both the case where the lower layer 22 contains no first antibacterial agent at all, and the case where trace amounts of the first antibacterial agent inevitably mix into the lower layer 22. Furthermore, for the same reason, it is preferable that the lower layer 22 also substantially contains no second antibacterial agent. That is, it is preferable that the lower layer 22 is substantially free of antibacterial agent. "Substantially free of antibacterial agent" means that, relative to the mass of the lower layer 22, the mass of the antibacterial agent contained in the lower layer 22 is less than 0.1% by mass, preferably less than 0.05% by mass.

[0054] When the top sheet 2 is a two-layer structure consisting of an upper layer 21 and a lower layer 22, the top sheet 2 can be a structure in which the upper layer 21 and the lower layer 22 are integrated within a single sheet, or it can be a structure in which the two sheets are simply overlapped one on top of the other.

[0055] The top sheet 2 is preferably composed of a fiber sheet such as a nonwoven fabric. The proportion of the first antibacterial agent in the top sheet 2, from the viewpoint of ensuring good ejection from the spinneret when spinning the constituent fibers of the top sheet 2 and improving the strength of the spun fibers, is preferably less than 3.0% by mass, more preferably 1.5% by mass or less, and even more preferably 1.0% by mass or less, relative to the mass of the upper layer 21. The lower limit of the mass of the first antibacterial agent contained in the upper layer 21 relative to the mass of the fiber can be set to 0.3% by mass.

[0056] The proportion of the first antibacterial agent can be measured by the following methods.

[0057] <Method for measuring the content ratio of the first antibacterial agent>

[0058] Weigh 1g of the top layer 21 of the diaper 1, chop it as finely as possible, and place it in a 300ml beaker. Then, add 200ml of deionized water to the beaker and stir with a magnetic stirrer to ensure the fibers are fully in contact with the water. While stirring the liquid, gradually add 3ml of concentrated hydrochloric acid (approximately 10M), stirring for another hour to dissolve the first antibacterial agent present on the surface of the fibers constituting the top layer 21. Next, add 6ml of 5.1M sodium hydroxide aqueous solution to neutralize the liquid, and then add 10ml of pH 10.7 buffer solution (containing 54.7ml of 28% NH3 aqueous solution and 0.535g of NH4Cl dissolved in deionized water) to fine-tune the pH.

[0059] Next, Chrome Black T reagent (obtained by dissolving 0.125 g of Chrome Black T powder and 1.125 g of hydroxylamine hydrochloride in 25 ml of anhydrous ethanol) was added as an indicator to turn the liquid a pale pink. Titration was performed using 0.0002 M EDTA·2Na as the titrant, and the volume (ml) of titrant added when the liquid changed from pink to pale blue to green was taken as the titration value A. The mass of the first antibacterial agent was then calculated using the following formula. In the formula, "5000000" refers to the volume (ml) of 1 mol of titrant.

[0060] Mass of the first antibacterial agent (g) = Titration value A × Mass of the first antibacterial agent per 1 mol / 5,000,000

[0061] The calculated mass of the antibacterial agent, as described above, represents the mass of the antibacterial agent contained in 1g of the upper layer 21. Therefore, 100 times the calculated mass of the antibacterial agent is the proportion of the first antibacterial agent.

[0062] When the first antibacterial agent is a metal oxide, the lower layer 22 of the top sheet 2 preferably contains a metal oxide different from the metal oxide contained in the first antibacterial agent. This allows for the imparting of an antibacterial effect to the upper layer 21, and a different effect to the lower layer 22, such as making the top sheet 2 appear white. "A metal oxide different from the metal oxide contained in the first antibacterial agent" means that, in the case where the first antibacterial agent is, for example, zinc oxide, the antibacterial agent contained in the lower layer 22 can be any of titanium dioxide, calcium carbonate, talc, clay, kaolin, silica, diatomaceous earth, magnesium carbonate, barium carbonate, magnesium sulfate, barium sulfate, calcium sulfate, aluminum hydroxide, magnesium hydroxide, calcium oxide, aluminum oxide, mica, glass powder, shirasu balloons, zeolite, and silicate clay. Titanium oxide is present, for example, as a white pigment incorporated into the fibers constituting the lower layer 22.

[0063] From the viewpoint of further enhancing the antibacterial effect produced by the first antibacterial agent, the preferred weight of the first antibacterial agent is 0.03 g / m³. 2 Above and 0.6g / m 2 The following is more preferably 0.05 g / m 2 Above and 0.3g / m 2 The following is a further preferred value: 0.07 g / m 2 Above and 0.1g / m 2 the following.

[0064] The weight of the first antibacterial agent can be measured by the following methods.

[0065] <Method for measuring the weight of the first antibacterial agent>

[0066] Cut 300mm from the top plate 2 The above slices. The area of ​​each slice is less than 300 mm². 2 In this case, slices are cut from multiple locations, so that their total area is 300 mm². 2 That's all. The slices are cut in a manner that includes both the upper and lower layers.

[0067] Next, a multi-stage solvent extraction method, switching from non-polar to polar solvents, was performed on the aforementioned slices to separate the antibacterial agents present in the slices, obtaining a solution containing a single composition. The obtained solution was then dried and solidified. 1 The chemical structure of antibacterial agents was identified using a combination of methods including ¹H-NMR (nuclear magnetic resonance), IR (infrared spectroscopy), LC (liquid chromatography), GC (gas chromatography), MS (mass spectrometry), GPC (gel permeation chromatography), and fluorescence X-ray diffraction. Furthermore, using antibacterial agents with specific chemical structures as standard substances, standard curves were constructed using known analytical techniques such as GC and LC to quantify the antibacterial agents in the slides. Based on the quantitative results, the mass of the antibacterial agents in the slides was determined. In cases where multiple antibacterial agents were present in the slides, the total mass of all antibacterial agents was calculated, and this total was taken as the mass of the antibacterial agents in the slide. Finally, the weight of the antibacterial agents was calculated by dividing the mass of the antibacterial agents in the slides by the area of ​​the slides.

[0068] Next, the second antibacterial agent will be explained. There are no particular restrictions on the type of second antibacterial agent, as long as its solubility in water is higher than that of the first antibacterial agent. In particular, cationic surfactants are preferred as the second antibacterial agent. Because cationic surfactants are readily soluble in water, the second antibacterial agent dissolves rapidly in urine upon contact and can be readily transferred to the absorbent core 32. Examples of cationic surfactants include tetraalkylammonium salts, trialkylbenzylammonium salts such as benzalkonium chloride, monoalkyltrimethylammonium salts, dialkyldimethylammonium salts, trialkylmonomethylammonium salts, and monoalkyldimethylbenzylammonium salts. These cationic surfactants can be used alone or in combination of two or more.

[0069] Monoalkyl dimethyl benzyl ammonium salts include benzalkonium cetyl phosphate salt and alkyl benzyl dimethyl ammonium chloride salt. Among them, benzalkonium cetyl phosphate salt is preferred.

[0070] The second antibacterial agent preferably contains plant extracts. The skin-moisturizing effects of plant extracts can further and effectively suppress rashes on the wearer's skin. Examples of plant extracts include witch hazel extract, oat extract, seaweed (fucus vesiculosus), grapefruit extract, burnet root extract, cypress extract, aloe vera extract, phellodendron bark extract, horsetail extract, chamomile extract, eucalyptus extract, peach leaf extract, and green tea extract.

[0071] Considering both the antibacterial effect and the prevention of viscosity in liquids containing antibacterial agents, the weight of the second antibacterial agent in absorbent 3 is 1 mg / m³. 2 Above and 80mg / m 2 The preferred dosage is 2.5 mg / m³. 2 Above and 80mg / m 2 The following is more preferably 20 mg / m² 2 Above and 80mg / m 2 The following is a further preferred value: 30 mg / m² 2 Above and 50mg / m 2 the following.

[0072] The weight of the second antibacterial agent can be measured by the following methods.

[0073] <Method for measuring the weight of the second antibacterial agent>

[0074] Cut a 300mm section from the absorber. 2 The above slices. When the slice area is less than 300 mm². 2 In this case, slices are cut from multiple locations, so that their total area is 300 mm². 2 That's all. The slices are cut in a manner that includes both the absorbent core and the encapsulated chip.

[0075] Next, the antibacterial agent in the slices cut from the absorbent is quantified using the same method as described in the <Method for Measuring the Gram Weight of the First Antibacterial Agent>. Based on this quantification result, the mass of the antibacterial agent in the slice is determined. If multiple antibacterial agents are present in the slice, the total mass of each antibacterial agent is calculated, and this total is taken as the mass of the antibacterial agent in the slice. Furthermore, the gram weight of the antibacterial agent is calculated by dividing the mass of the antibacterial agent in the slice by the area of ​​the slice.

[0076] From the viewpoint of more effectively preventing bacterial growth in the absorbent core 32, the second antimicrobial agent is preferably contained within the absorbent body 3 and the chip 31. The second antimicrobial agent may be contained throughout the entire area of ​​the chip 31, or it may be contained only in a portion of the chip 31. In this embodiment, the chip 31 is as follows... Figure 1 The diagram shows an upper package chip 31a and a lower package chip 31b. In this case, the second antibacterial agent may be contained in either the upper package chip 31a or the lower package chip 31b, but it is preferred to contain it in at least the upper package chip 31a, and more preferably in both the upper package chip 31a and the lower package chip 31b.

[0077] Furthermore, according to the same viewpoint, the second antibacterial agent is preferably contained in the absorbent 3 as a whole at the same concentration. In other words, it is preferable that the second antibacterial agent is contained in a uniformly dispersed manner throughout the absorbent 3.

[0078] The second antibacterial agent may also be contained unevenly within the absorbent body 3. Specifically, the second antibacterial agent may be more abundant on the ventral side of the absorbent body 3 than on the dorsal side, or vice versa. Generally, since the wearer's excretory parts, such as the urethra, are located on the ventral side of the wearer, it is preferable that the second antibacterial agent dissolves more easily from the absorbent body 3 into the urine, thus more effectively preventing bacterial growth in the absorbent core 32. Therefore, it is preferable that the second antibacterial agent is more abundant on the ventral side of the absorbent body 3 than on the dorsal side.

[0079] In this embodiment, the chip 31 and the absorbent core 32 are preferably bonded via a first adhesive 5a and a third adhesive 5b. Specifically, the skin-facing surface of the absorbent core 32 is preferably bonded to the non-skin-facing surface of the upper chip 31a via the first adhesive 5a. Furthermore, the non-skin-facing surface of the absorbent core 32 is preferably bonded to the skin-facing surface of the lower chip 31b via the third adhesive 5b.

[0080] Furthermore, the top sheet 2 and the encapsulated chip 31 are preferably bonded via a second adhesive 5c. Specifically, the non-skin-facing surface of the lower layer 22 of the top sheet 2 is preferably bonded to the skin-facing surface of the upper encapsulated chip 31a via the second adhesive 5c.

[0081] When focusing on the upper packaging chip 31a, a first adhesive 5a and a second adhesive 5c are applied to the non-skin-facing side and the skin-facing side of the upper packaging chip 31a, respectively. In this case, it is preferable that the weight of the first adhesive 5a is less than the weight of the second adhesive 5c. In this way, when the second antibacterial agent contained in the upper packaging chip 31a comes into contact with urine and dissolves from the upper packaging chip 31a, it is easily transferred to the absorbent core 32 along with the urine, thus more effectively preventing the growth of bacteria in the absorbent core 32. From the viewpoint of making this effect more significant, the ratio (A2 / A1) of the weight A2 of the first adhesive 5a on the non-skin-facing side of the upper packaging chip 31a to the weight A1 of the second adhesive 5c on the skin-facing side of the upper packaging chip 31a is preferably 1.0 or less, more preferably 0.8 or less, and even more preferably 0.6 or less. The lower limit value of A2 / A1 can be set to 0.1.

[0082] From the viewpoint of more effectively preventing the growth of bacteria within the absorbent core 32, the basis weight of the first adhesive is preferably 1 g / m³. 2 Above and 8g / m 2 The following is more preferably 1.5 g / m 2 Above and 6g / m 2 The following is a further preferred value: 2g / m 2 Above and 5g / m 2 the following.

[0083] From the same point of view, the preferred basis weight of the second adhesive is 1.5 g / m³. 2 Above and 10g / m 2 The preferred value is 2g / m 2 Above and 8g / m 2 The following is a further preferred value: 3g / m 2 Above and 6g / m 2 the following.

[0084] The basis weight of the adhesive can be measured using the following methods.

[0085] <Methods for measuring the weight of adhesives>

[0086] The following explanation uses the measurement method for the basis weight of the first adhesive as an example to illustrate the method for measuring the basis weight of the adhesive. The basis weight of the second adhesive can also be measured in the same way.

[0087] First, the area covered by the first adhesive is measured. Specifically, the absorbent top sheet is carefully peeled off from the upper chip. Ideally, the first adhesive should remain on the top sheet as little as possible. Then, a print toner is applied to the skin-facing side of the upper chip, i.e., the side coated with the first adhesive, allowing it to adhere to the first adhesive. In this way, the application of the first adhesive is revealed using the toner, the skin-facing side of the upper chip is scanned, and the area covered by the first adhesive is measured using area calculation software.

[0088] Next, the amount of the first adhesive applied is measured. Specifically, the upper packaging chip, whose application area of ​​the first adhesive has been measured, is carefully peeled off from the absorbent core. At this time, it is preferable to remove the second adhesive from the non-skin-facing side of the upper packaging chip. If the packaging chip is composed of a single sheet, the portion of the packaging chip read by the scanner described above is cut out, and this cut-out portion is used as the upper packaging chip. Furthermore, the skin-facing side of the upper packaging chip is immersed in toluene and then dried. If the second adhesive remains on the non-skin-facing side of the upper packaging chip, when immersing the upper packaging chip in toluene, it is preferable to prevent the toluene from reaching the non-skin-facing side of the upper packaging chip. Furthermore, the amount of the first adhesive applied can be calculated by subtracting the mass of the upper packaging chip after immersion in toluene and drying from the mass of the upper packaging chip before immersion in toluene.

[0089] Furthermore, the weight of the first adhesive can be determined by dividing the amount of the first adhesive applied by the area covered.

[0090] In this embodiment, it is preferable that the upper layer 21 of the top sheet 2 is not coated with an adhesive. When the upper layer 21 contains a first antibacterial agent, not coating the upper layer 21 with an adhesive means that the first antibacterial agent does not come into contact with the adhesive. In this way, the first antibacterial agent contained in the upper layer 21 can easily transfer to the feces attached to the top sheet 2, which can more effectively prevent rashes. From this point of view, the upper layer 21 is preferably made of a nonwoven fabric that does not use adhesives, such as hot-air nonwoven fabric, spunbond nonwoven fabric, or spunlace nonwoven fabric. The upper layer 21 and the lower layer 22 of the top sheet 2 are preferably joined by heat fusion.

[0091] Plant extracts may be present in either or both of the top sheet 2 and the absorbent body 3. The skin-moisturizing effect of the plant extracts can effectively suppress rashes on the wearer's skin. The same plant extracts that can be included in the second antibacterial agent can be used. Plant extracts may be present in either or both of the upper layer 21 and lower layer 22 of the top sheet 2. Plant extracts may also be present in either or both of the absorbent core 32 and the outer layer 31 of the absorbent body 3.

[0092] The present invention has been described above based on its embodiments, but the present invention is not limited to the above embodiments and can be appropriately modified.

[0093] For example, in the above embodiments, the absorbent article 1 contains two antibacterial agents, namely a first antibacterial agent and a second antibacterial agent. However, the absorbent article of the present invention may also contain a third antibacterial agent with different solubility in water than the first and second antibacterial agents.

[0094] Regarding the above-described embodiments, the present invention further discloses the following absorbent articles.

[0095] <1>

[0096] An absorbent article having an absorbent body and a top sheet disposed on the skin-facing side of the absorbent body.

[0097] The aforementioned top sheet has an upper layer and a lower layer located on the non-skin-facing side of the upper layer.

[0098] The upper layer contains a first antibacterial agent, and the absorbent contains a second antibacterial agent.

[0099] The first antibacterial agent is less soluble in water than the second antibacterial agent.

[0100] <2>

[0101] As mentioned above <1> The absorbent materials recorded in the text, among which,

[0102] The difference in solubility between the first antibacterial agent and the second antibacterial agent is preferably 0.5 g / 100 ml or more, more preferably 1 g / 100 ml or more, and even more preferably 2 g / 100 ml or more.

[0103] <3>

[0104] As mentioned above <1> or <2> The absorbent materials recorded in the text, among which,

[0105] The solubility of the first antibacterial agent is preferably 0.01 g / 100 ml or more and 0.5 g / 100 ml or less, more preferably 0.03 g / 100 ml or more and 0.3 g / 100 ml or less, and even more preferably 0.05 g / 100 ml or more and 0.2 g / 100 ml or less.

[0106] <4>

[0107] As mentioned above <1> to <3> Any of the absorbent articles recorded in the text, among which,

[0108] The solubility of the second antibacterial agent is preferably 1g / 100ml or more and 10g / 100ml or less, more preferably 2g / 100ml or more and 8g / 100ml or less, and even more preferably 4g / 100ml or more and 6g / 100ml or less.

[0109] <5>

[0110] As mentioned above <1> to <4> Any of the absorbent articles recorded in the text, among which,

[0111] The lower layer mentioned above does not actually contain any antibacterial agents.

[0112] <6>

[0113] As mentioned above <1> to <5> Any of the absorbent articles recorded in the text, among which,

[0114] The first antibacterial agent does not come into contact with the adhesive.

[0115] <7>

[0116] As mentioned above <1> to <6> Any of the absorbent articles recorded in the text, among which,

[0117] The absorber described above has an absorbent core and a packaged chip covering the absorbent core.

[0118] The second antibacterial agent is contained in either the absorbent core or the coated chip, preferably in both the absorbent core and the coated chip.

[0119] <8>

[0120] As mentioned above <7> The absorbent materials recorded in the text, among which,

[0121] The aforementioned packaged chip has an upper packaged chip covering the skin-facing side of the absorbent core.

[0122] The skin-facing surface of the absorbent core and the non-skin-facing surface of the upper package chip are bonded together by a first adhesive.

[0123] The non-skin-facing surface of the top sheet is bonded to the skin-facing surface of the upper encapsulated chip using a second adhesive.

[0124] The weight of the first adhesive is smaller than that of the second adhesive.

[0125] <9>

[0126] As mentioned above <8> The absorbent materials recorded in the text, among which,

[0127] The ratio of the weight of the first adhesive to the weight of the second adhesive is preferably 1.0 or less, more preferably 0.8 or less, even more preferably 0.6 or less, and even more preferably 0.1 or more.

[0128] <10>

[0129] As mentioned above <8> or <9> The absorbent materials recorded in the text, among which,

[0130] The preferred basis weight of the first adhesive is 1 g / m³. 2 Above and 8g / m 2 The following is more preferably 1.5 g / m 2 Above and 6g / m 2 The following is a further preferred value: 2g / m 2 Above and 5g / m 2 the following.

[0131] <11>

[0132] As mentioned above <8> to <10> Any of the absorbent articles recorded in the text, among which,

[0133] The preferred basis weight of the second adhesive is 1.5 g / m³. 2 Above and 10g / m 2 The preferred value is 2g / m 2 Above and 8g / m 2 The following is a further preferred value: 3g / m 2 Above and 6g / m 2 the following.

[0134] <12>

[0135] As mentioned above <1> to <11> Any of the absorbent articles recorded in the text, among which,

[0136] The aforementioned absorbent articles have a crotch portion located at the wearer's groin area, and ventral and dorsal portions extending forward and backward therefrom.

[0137] The second antibacterial agent is contained in the entire absorbent at the same concentration.

[0138] <13>

[0139] As mentioned above <1> to <11> Any of the absorbent articles recorded in the text, among which,

[0140] The aforementioned absorbent articles have a crotch portion located at the wearer's groin area, and ventral and dorsal portions extending forward and backward therefrom.

[0141] Compared to the dorsal side of the absorbent, the ventral side contains more of the second antibacterial agent.

[0142] <14>

[0143] As mentioned above <1> to <13> Any of the absorbent articles recorded in the text, among which,

[0144] The first antibacterial agent contains metal oxides.

[0145] <15>

[0146] As mentioned above <14> The absorbent materials recorded in the text, among which,

[0147] The aforementioned metal oxide is zinc oxide.

[0148] <16>

[0149] As mentioned above <14> or <15> The absorbent materials recorded in the text, among which,

[0150] The lower layer contains a metal oxide that is different from the metal oxide contained in the upper layer.

[0151] <17>

[0152] As mentioned above <16> The absorbent materials recorded in the text, among which,

[0153] The metal oxides that are different from the metal oxides mentioned above are selected from titanium dioxide, calcium carbonate, talc, clay, kaolin, silicon dioxide, diatomaceous earth, magnesium carbonate, barium carbonate, magnesium sulfate, barium sulfate, calcium sulfate, aluminum hydroxide, magnesium hydroxide, calcium oxide, aluminum oxide, mica, glass powder, hollow spheres of white sand, zeolite, and silicate clay.

[0154] <18>

[0155] As mentioned above <1> to <17> Any of the absorbent articles recorded in the text, among which,

[0156] The proportion of the first antibacterial agent relative to the mass of the upper layer is less than 3.0% by mass, preferably less than 1.5% by mass, more preferably less than 1.0% by mass, and even more preferably more than 0.3% by mass.

[0157] <19>

[0158] As mentioned above <1> to <18> Any of the absorbent articles recorded in the text, among which,

[0159] The first antibacterial agent is soluble in solutions containing protein.

[0160] <20>

[0161] As mentioned above <1> to <19> Any of the absorbent articles recorded in the text, among which,

[0162] The second antibacterial agent has a weight of 1 mg / m³. 2 Above and 80mg / m 2 The preferred dosage is 2.5 mg / m³. 2 Above and 80mg / m 2The following is more preferably 20 mg / m² 2 Above and 80mg / m 2 The following is a further preferred value: 30 mg / m² 2 Above and 50mg / m 2 the following.

[0163] <21>

[0164] As mentioned above <1> to <20> Any of the absorbent articles recorded in the text, among which,

[0165] The second antibacterial agent is a cationic surfactant.

[0166] <22>

[0167] As mentioned above <1> to <21> Any of the absorbent articles recorded in the text, among which,

[0168] The aforementioned top film or absorbent contains plant extracts.

[0169] Industrial availability

[0170] According to the present invention, an absorbent article is provided that can prevent rashes caused by feces and the growth of bacteria in the absorbent core for a long time.

Claims

1. An absorbent article, characterized in that: It has an absorbent body and a top plate disposed on the skin-facing side of the absorbent body. The absorber has an absorbent core and a cover chip covering the absorbent core. The top sheet has an upper layer and a lower layer located on the non-skin-facing side of the upper layer. The upper layer contains a first antibacterial agent, and the chip contains a second antibacterial agent. The first antibacterial agent is less soluble in water than the second antibacterial agent. The first antibacterial agent contains metal oxides. The second antibacterial agent contains a cationic surfactant. The chip has an upper chip covering the skin-facing side of the absorbent core. The skin-facing side of the absorbent core and the non-skin-facing side of the upper encapsulated chip are bonded together by a first adhesive. The non-skin-facing surface of the top sheet is bonded to the skin-facing surface of the upper encapsulated chip using a second adhesive. The weight ratio of the first adhesive to the second adhesive is between 1.0 and 0.

1. The basis weight of the first adhesive is 1 g / m³. 2 Above and 8g / m 2 the following, The basis weight of the second adhesive is 1.5 g / m². 2 Above and 10g / m 2 the following.

2. The absorbent article as claimed in claim 1, characterized in that: The difference in solubility between the first and second antibacterial agents is greater than 0.5 g / 100 ml.

3. The absorbent article as described in claim 1 or 2, characterized in that: The solubility of the first antibacterial agent is greater than 0.01g / 100ml and less than 0.5g / 100ml.

4. The absorbent article according to any one of claims 1 to 3, characterized in that: The solubility of the second antibacterial agent is above 1g / 100ml and below 10g / 100ml.

5. The absorbent article as described in any one of claims 1 to 4, characterized in that: The lower layer does not actually contain any antibacterial agents.

6. The absorbent article according to any one of claims 1 to 5, characterized in that: The first antibacterial agent does not come into contact with the adhesive.

7. The absorbent article according to any one of claims 1 to 6, characterized in that: A second antibacterial agent is also contained in the absorbent core.

8. The absorbent article as claimed in claim 7, characterized in that: The absorbent article has a crotch portion disposed at the wearer's groin area, and ventral and dorsal portions extending forward and backward therefrom. The second antibacterial agent is contained in the absorbent at the same concentration throughout.

9. The absorbent article as claimed in claim 7, characterized in that: The absorbent article has a crotch portion disposed at the wearer's groin area, and ventral and dorsal portions extending forward and backward therefrom. Compared to the dorsal side of the absorbent, the ventral side contains more of the second antibacterial agent.

10. The absorbent article according to any one of claims 1 to 9, characterized in that: The metal oxide is zinc oxide.

11. The absorbent article according to any one of claims 1 to 10, characterized in that: The lower layer contains a metal oxide that is different from the metal oxide contained in the upper layer.

12. The absorbent article as claimed in claim 11, characterized in that: The metal oxides, which are different from the metal oxides mentioned above, are selected from titanium oxide, calcium carbonate, talc, clay, kaolin, silicon dioxide, diatomaceous earth, magnesium carbonate, barium carbonate, magnesium sulfate, barium sulfate, calcium sulfate, aluminum hydroxide, magnesium hydroxide, calcium oxide, aluminum oxide, mica, glass powder, hollow white sand spheres, zeolite, and silicate clay.

13. The absorbent article according to any one of claims 1 to 12, characterized in that: The proportion of the first antibacterial agent relative to the mass of the upper layer is more than 0.3% by mass and less than 3.0% by mass.

14. The absorbent article according to any one of claims 1 to 13, characterized in that: The first antibacterial agent is soluble in solutions containing protein.

15. The absorbent article according to any one of claims 1 to 14, characterized in that: The second antibacterial agent has a weight of 1 mg / m³. 2 Above and 80mg / m 2 the following.

16. The absorbent article according to any one of claims 1 to 15, characterized in that: The second antibacterial agent is a cationic surfactant.

17. The absorbent article according to any one of claims 1 to 16, characterized in that: The top sheet or the absorber contains plant extracts.

18. The absorbent article according to any one of claims 1 to 17, characterized in that: No adhesive is applied to the upper layer.

19. The absorbent article according to any one of claims 1 to 18, characterized in that: The first antibacterial agent includes zinc oxide, silver oxide, aluminum oxide, titanium oxide, calcium oxide, or magnesium oxide.

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