Absorbent panty-type items

Abstract

To provide an underpants-type absorbent article that ensures liquid permeation and prevents liquid return, and markedly suppresses propagation of germs and occurrence of ammonia odor even when body fluid remains on the top sheet.SOLUTION: An underpants-type absorbent article has a ventral band member 30 of a ventral part 13, a dorsal band member 40 of a dorsal part 15, a crotch band member 50 of a crotch part 14 therebetween, and a waist opening 11 and a leg opening 12 formed by joining together respective both ends of the ventral band member 30 and the dorsal band member 40. An absorbable body 20 has both ends in a longitudinal direction joined to the skin side faces of the ventral band member 30 and the dorsal band member 40. The ventral band member 30, dorsal band member 40 and crotch band member 50 each include an interior nonwoven fabric sheet, an exterior nonwoven fabric sheet and a plurality of elastic stretching members. The top sheet 21 of the absorbable body 20 has a first fiber layer 211 including durable hydrophilic fibers, and a second fiber layer 212 including general hydrophilic fibers and antibacterial fibers. The durable hydrophilic fibers, general hydrophilic fibers, and antibacterial fibers each have a predetermined basis weight in the underpants-type absorbent article.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This invention relates to a pant-type absorbent article. [Background technology]

[0002] Recently, there has been a very high demand for adding antibacterial and deodorizing functions to absorbent products such as disposable diapers, light incontinence products, and pet pads. Antibacterial function, for example, suppresses the growth of various bacteria, such as ammonia-producing bacteria, after urination. In response to this demand, various absorbent products with antibacterial and / or deodorizing functions have been proposed.

[0003] Patent Document 1 discloses an absorbent article in which an absorbent core is wrapped in a carrier sheet coated with a deodorant or antibacterial agent, and the entire article is further wrapped in a surface sheet (Claim 1, Claim 7).

[0004] Patent Document 2 discloses a diaper comprising a surface material that comes into contact with the skin, which includes synthetic fibers containing zeolite supported with silver ions, copper ions, or zinc ions; an internal fiber sheet corresponding to an absorbent, which includes the zeolite and fibers containing a deodorant; and a superabsorbent polymer inner layer (Claim 1). As the synthetic fibers containing zeolite, polyethylene terephthalate fibers, polyethylene fibers, polypropylene fibers, etc., can be used (Paragraph 0007). Furthermore, as the fibers constituting the internal fiber sheet, polyester fibers, etc., can be used (Paragraph 0009).

[0005] Patent Document 3 discloses an antibacterial cellulose fiber (product name: Cellgaia®, manufactured by Rengo Co., Ltd.) in which zeolite is supported inside the cellulose fiber and Ag, Cu, etc., is supported within the zeolite, as well as woven fabrics, nonwoven fabrics, and paper containing the antibacterial cellulose fiber. For example, by making paper using the cellulose fiber, the paper itself can be given a deodorizing function. It is also described that woven fabrics, nonwoven fabrics, or paper containing the cellulose fiber can be used as a material for disposable diapers (paragraph 0018).

[0006] Patent Document 4 discloses an absorbent article comprising a topsheet, a backsheet, an absorber disposed therebetween, a region between the absorber and the backsheet, and a hydrophilic deodorant sheet disposed in a region between the topsheet and the backsheet around the absorber, wherein the hydrophilic deodorant sheet contains the antibacterial cellulose fibers described in Patent Document 3 (Claim 1, Paragraph 0026).

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0008] In recent absorbent articles, it is required to absorb multiple excretions of body fluids, and since there are many opportunities to wear a single absorbent article for a long time, it is considered to be in an environment where various germs are likely to multiply. In particular, care recipients with a relatively large excretion amount of body fluids often wear pant - type disposable diapers (pant - type absorbent articles). In such cases, since the disposable diaper adheres to the wearer's body and is exposed to the body temperature of the wearer for a long time, an environment is easily formed that promotes the growth of germs and the generation of unpleasant odors such as ammonia odor. Although the absorbent articles described in Patent Documents 1 to 4 have a certain antibacterial function, the topsheet that contacts the skin of the wearer does not contain an antibacterial agent. Therefore, it is not possible to effectively exert an antibacterial action (such as an inhibitory action on bacterial growth) on the body fluids remaining on the topsheet.

[0009] The present invention has been made in view of the above problems, and the object of the present invention is to provide a pant-type absorbent article that has excellent liquid permeability and liquid return properties, and in which the growth of bacteria and the generation of ammonia odor are significantly suppressed even if bodily fluids remain on the top sheet. [Means for solving the problem]

[0010] In view of the above problems, the inventors conducted diligent research. As a result, the inventors found that the above problems can be solved by arranging the top sheet in a specific ratio, with the top sheet comprising two fiber layers including antibacterial fibers, the first fiber layer located on the skin side of the top sheet comprising durable hydrophilic fibers, and the second fiber layer located on the non-skin side of the top sheet comprising antibacterial fibers and general hydrophilic fibers, thereby completing the present invention. The present invention relates to the following pant-type absorbent article.

[0011] (1) A first aspect of the present invention is a pant-type absorbent article comprising: an abdominal band member disposed on the abdominal side of the wearer; a back band member disposed on the back side of the wearer; a crotch band member interposed between the abdominal band member and the back band member and disposed on the crotch of the wearer to support an absorbent body; and a waist opening and a leg opening formed by joining the widthwise ends of the abdominal band member and the widthwise ends of the back band member, The absorbent body comprises a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent material disposed between the top sheet and the back sheet, with both longitudinal ends joined to the skin surface of the ventral band member and the skin surface of the dorsal band member, respectively. The ventral band member, the dorsal band member, and the crotch band member each comprise an inner nonwoven fabric sheet located on the skin side, an outer nonwoven fabric sheet located on the non-skin side, and a plurality of elastic stretch members positioned between the inner nonwoven fabric sheet and the outer nonwoven fabric sheet. The topsheet includes a first fiber layer containing durable hydrophilic fibers, and a second fiber layer adjacent to the non-skin contacting surface of the first fiber layer and containing general hydrophilic fibers and antibacterial fibers. The skin contacting surface of the first fiber layer constitutes the skin contacting surface of the topsheet, and the non-skin contacting surface of the second fiber layer constitutes the non-skin contacting surface of the topsheet. The basis weight of the durable hydrophilic fibers in the first fiber layer is 3 g / m 2 or more and 15 g / m 2 or less. The basis weight of the general hydrophilic fibers in the second fiber layer is 7 g / m 2 or more and 25 g / m 2 or less. The basis weight of the antibacterial fibers is 1 g / m 2 or more and 6 g / m 2 or less. The absorbent article is a pant-type absorbent article. However, the general hydrophilic fibers and the durable hydrophilic fibers are defined by hydrophilicity evaluation in which, when 100 μL of 0.9% saline is dropped every 30 seconds at the same position of an air-through non-woven fabric with a basis weight of 20 g / m 2 containing fibers, if the dropped saline does not penetrate the air-through non-woven fabric and the number of drops when it forms droplets on the air-through non-woven fabric is observed. The fibers contained in the air-through non-woven fabric with a hydrophilicity evaluation of 1 or more and 8 or less are general hydrophilic fibers, and the fibers contained in the air-through non-woven fabric with a hydrophilicity evaluation of 9 or more are durable hydrophilic fibers. (2) A second aspect of the present invention is the pant-type absorbent article according to (1), wherein the topsheet is an air-through non-woven fabric. (3) A third aspect of the present invention is the pant-type absorbent article according to (1) or (2), wherein the basis weight of the topsheet is 18 g / m 2 or more and 30 g / m 2 or less. (4) A fourth aspect of the present invention is the pant-type absorbent article according to any one of (1) to (3), further comprising an absorber covering sheet disposed between the topsheet and the absorber, wherein the absorber covering sheet contains pulp fibers. (5) A fifth aspect of the present invention is a pant-type absorbent article according to any one of (1) to (4), characterized in that the durable hydrophilic fibers contained in the first fiber layer are treated with a castor oil derivative, and the general hydrophilic fibers contained in the second fiber layer are treated with an anionic surfactant. [Effects of the Invention]

[0012] According to the present invention, a pant-type absorbent article is provided that has excellent liquid permeability and liquid return properties, and even if bodily fluids remain on the top sheet, the growth of bacteria and the generation of ammonia odor are significantly suppressed. [Brief explanation of the drawing]

[0013] [Figure 1] This is a schematic perspective view showing the appearance of a pant-type absorbent article according to the first embodiment of the present invention. [Figure 2] Figure 1 is a schematic unfolded diagram of the pant-type absorbent material. [Figure 3] Figure 2 shows a schematic cross-sectional view in the width direction of a pant-type absorbent article along the X1-X1 cutting line. [Figure 4] This is a schematic cross-sectional view in the width direction showing a modified example of the absorbent body. [Figure 5] This is a schematic cross-sectional view showing the configuration of the top sheet. [Modes for carrying out the invention]

[0014] In this specification, wearing of absorbent pants refers to the state in which the absorbent pants are worn on the body, regardless of whether or not bodily fluids have been absorbed. In absorbent pants, the longitudinal direction is the direction indicated by Y in the figure, which extends from the front to the back of the body through the wearer's crotch when the absorbent pants are worn on the body; the width direction is the direction indicated by X in the figure, which is perpendicular to the length direction; and the thickness direction is the direction indicated by Z in the figure, which is the direction in which each component is stacked. Furthermore, the skin-contacting surface (hereinafter also simply referred to as the "skin side" or "skin side") is the surface of each component such as the absorbent material that is positioned on the wearer's skin side when worn, and the non-skin-contacting surface (hereinafter also simply referred to as the "non-skin side" or "non-skin side") is the surface of each component such as the absorbent material that is facing away from the wearer's skin side when worn. Bodily fluids refer to liquids that are expelled from the body to the outside, such as urine, blood, and water in loose stools.

[0015] <Panty-type absorbent items> The following description of the pant-type absorbent article 1 of this embodiment will be made with reference to the drawings. Figures 1 and 2 show a schematic perspective view and a schematic unfolded view of the external appearance of the pant-type absorbent article 1. Figure 3 is a cross-sectional view of the absorbent body 20 of Figure 2 along the line X1-X1, and Figure 4 shows an absorbent body 26 of another embodiment. Figure 5 shows the top sheet 21. These drawings do not specify the shape, dimensions, size relationships, etc., of each component in the pant-type absorbent article 1.

[0016] As shown in Figure 1, the pant-type absorbent article 1 comprises an abdominal band member 30 positioned to primarily contact the wearer's abdominal portion 13, a back band member 40 positioned to primarily contact the wearer's back portion 15, a crotch band member 50 interposed between the abdominal band member 30 and the back band member 40 to primarily contact the wearer's crotch portion 14 and support the absorbent body 20, and a waist opening 11 and a pair of leg openings 12 formed by joining the widthwise ends of the abdominal band member 30 and the widthwise ends of the back band member 40. Here, the absorbent body 20 has an elongated shape in the front-to-back direction that covers the wearer's crotch portion 14 from the front and back of the body. The waist opening 11 is located above the abdominal portion 13 and the back portion 15, and the pair of leg openings 12 are formed on both the left and right sides of the crotch portion 14 between the abdominal portion 13 and the back portion 15. In this embodiment, the absorbent pants 1 is constructed from an integrated outer body extending from the ventral band member 30 through the crotch band member 50 to the dorsal band member 40. However, the invention is not limited to this configuration, and the ventral band member 30 and the dorsal band member 40 may be separate components connected by an absorbent body 20 to form an integrated absorbent pants 1.

[0017] Furthermore, the top sheet 21 of the absorbent body 20 includes a first fiber layer 211 located on the skin side of the wearer and a second fiber layer 212 located on the non-skin side of the wearer. The first fiber layer 211 mainly contains durable hydrophilic fibers, and the second fiber layer 212 mainly contains antibacterial fibers and general hydrophilic fibers. According to this embodiment, by arranging the first fiber layer 211 and the second fiber layer 212 having the above-described configurations in a predetermined ratio, the permeability of body fluids of the absorbent body 20 is improved, and a pant-type absorbent article can be obtained that has excellent antibacterial properties and significantly suppresses the growth of bacteria and the generation of ammonia odor even if body fluids remain on the top sheet 21.

[0018] The following will provide a more detailed explanation of each component, in the following order: the ventral band member 30, the dorsal band member 40, the crotch band member 50, and the absorbent main body 20.

[0019] <Ventral band member, dorsal band member, and crotch band member> The ventral band member 30 and the dorsal band member 40 are formed by overlapping multiple nonwoven fabrics from the non-skin side onto the front end (ventral end) and rear end (dorsal end) of the absorbent body 20. The crotch band member 50 is interposed between the ventral band member 30 and the dorsal band member 40, and is similarly formed by overlapping multiple nonwoven fabrics from the non-skin side.

[0020] In this embodiment, the abdominal band member 30, the dorsal band member 40, and the crotch band member 50 each comprise an outer nonwoven fabric sheet 301, 401, and 501 located on the non-skin side of the wearer, an inner nonwoven fabric sheet 302, 402, and 502 located on the skin side of the wearer, and a plurality of elastic stretch members (not shown) positioned at predetermined locations between them. The outer nonwoven fabric sheets 301, 401, 501 and the inner nonwoven fabric sheets 302, 402, 502 are folded in half along the center line of the absorbent body 20 so that the absorbent body 20 is on the inside, and the side edges of the abdominal portion 13 and the back portion 15 are connected with overlapping portions. As a result, the outer nonwoven fabric sheets 301, 401, 501 form an elastic waist opening 11 and a pair of leg openings 12, and the pant-type absorbent article 1 as a whole is configured to be a removable pant. When the pant-type absorbent article 1 is worn, the abdominal portion 13 covers the waist on the wearer's front side, and the back portion 15 covers the waist on the wearer's back side.

[0021] The inner nonwoven fabric sheets 302, 402, and 502 are laminated inside the outer nonwoven fabric sheets 301, 401, and 501 to increase the strength of the ventral band member 30 and the dorsal band member 40. The outer nonwoven fabric sheets 301, 401, and 501 and the inner nonwoven fabric sheets 302, 402, and 502 can be made of nonwoven fabric containing fibers made of thermoplastic resins such as polypropylene, polyester, and polyethylene. Specific examples of such nonwoven fabrics include thermal bond nonwoven fabrics, air-through nonwoven fabrics, and spunbond nonwoven fabrics. Among these, air-through nonwoven fabrics and spunbond nonwoven fabrics are preferred. The basis weight of the nonwoven fabric is, for example, 18 g / m². 2 More than 40g / m 2 The range is as follows:

[0022] The longitudinal dimension of the nonwoven fabric sheet 302 of the ventral band member 30 is, for example, in the range of 40 mm to 80 mm, and the longitudinal dimension of the nonwoven fabric sheet 402 of the dorsal band member 40 is, for example, in the range of 50 mm to 100 mm. The nonwoven fabric sheet 302 of the ventral band member 30 and the absorbent body 20 overlap in the longitudinal dimension for, for example, in the range of 20 mm to 30 mm, and the nonwoven fabric sheet 402 of the dorsal band member 40 and the absorbent body 20 overlap in the longitudinal dimension for, for example, in the range of 20 mm to 40 mm. By making the dimensions of the nonwoven fabric sheets 302, 402, and 502 within the above ranges, the breathability of the pant-type absorbent article 1 and the feel of the nonwoven fabric sheets against the skin are improved, including the area of ​​the dorsal portion 15.

[0023] <Elastic and expandable material> In the pant-type absorbent article 1, a plurality of elastic stretch members (not shown) are placed between the outer nonwoven fabric sheets 301, 401, 501 and the inner nonwoven fabric sheets 302, 402, 502 in predetermined areas such as the periphery of the waist opening 11, the periphery of the leg openings 12, the abdominal portion 13, the back portion 15, and the crotch portion 14, and are joined to the outer nonwoven fabric sheets 301, 401, 501 and the inner nonwoven fabric sheets 302, 402, 502. When stretched, the elastic stretch members are joined, for example, to the bottom of the embossed pattern of the inner nonwoven fabric sheets 302, 402, 502. With this configuration, when the pant-type absorbent article 1 is worn, pleats are formed in the inner nonwoven fabric sheets 302, 402, and 502 along the embossed pattern of the uneven surface, and a gap is maintained between the wearer and the inner nonwoven fabric sheets 302, 402, and 502 of the pant-type absorbent article 1, thereby maintaining good breathability of the pant-type absorbent article 1. Preferably, the inner nonwoven fabric sheets 302, 402, and 502 and the elastic stretch member are bonded to each other via, for example, a hot melt adhesive with only the elastic stretch member interposed. Any elastic member commonly used in this field can be used as the elastic stretch member, for example, thread-like, string-like, or flat-shaped materials such as natural rubber, synthetic rubber, or polyurethane, and their thickness is, for example, in the range of 620 dtex or less.

[0024] <Absorbent body of the first embodiment> As shown in Figure 3, the absorbent body 20 is based on a top sheet 21, an absorbent 22, and a back sheet 23, which are laminated from the skin side to the non-skin side. The absorbent body 20 of this embodiment may have a pair of three-dimensional gathers 24 extending in the longitudinal direction near both ends in the width direction of the skin side of the top sheet 21, if necessary. Various known modifications can be made to the absorbent body 20. The configuration of each component will be described in more detail below, in the order of top sheet 21, absorbent 22, back sheet 23, and three-dimensional gathers 24.

[0025] <Top sheet> As shown in Figure 5, the top sheet 21 includes a first fiber layer 211 located on the skin side of the wearer and a second fiber layer 212 located on the non-skin side of the wearer. Therefore, the skin side of the first fiber layer 211 becomes the skin side of the top sheet 21, and the non-skin side of the second fiber layer 212 becomes the non-skin side of the top sheet 21. The first fiber layer 211 includes durable hydrophilic fibers, and the second fiber layer 212 includes antibacterial fibers and general hydrophilic fibers. The first fiber layer 211 may consist of durable hydrophilic fibers, and may also include other fibers insofar as they do not impair the effect of the water-resistant hydrophilic fibers. The second fiber layer 212 may consist of general hydrophilic fibers and antibacterial fibers, and may also include other fibers insofar as they do not impair the effect of these fibers. Other fibers in the first fiber layer 211 and the second fiber layer 212 include, for example, one or more types of synthetic fibers made of synthetic resins such as polypropylene and polyethylene, regenerated fibers such as rayon, and natural fibers such as cotton and cellulose fibers.

[0026] As the first fiber layer 211 and the second fiber layer 212, for example, a substrate in the form of a sheet, film, etc., can be used. Specific examples of the substrate from the viewpoint of liquid permeability include, for example, nonwoven fabrics such as air-through nonwoven fabric, thermal-bonded nonwoven fabric, and spunbond nonwoven fabric; composite nonwoven fabrics such as thermal-bonded nonwoven fabric / spunbond nonwoven fabric laminates; foamed films such as urethane foam; and composite sheets which are laminates of two or more of these. Among these, nonwoven fabrics are preferred from the viewpoint of liquid permeability, and air-through nonwoven fabrics are more preferred.

[0027] The first fiber layer 211 and the second fiber layer 212 may be embossed or perforated on their surfaces according to known methods in order to improve liquid permeability. Furthermore, the first fiber layer 211 and the second fiber layer 212 may contain one or more of the following in order to reduce skin irritation: lotion, antioxidant, anti-inflammatory component, pH adjuster, moisturizer, etc. The top sheet 21 may be coated with an organic acid such as citric acid, glutamic acid, or malic acid as a weakly acidic solution, to the extent that it does not impair water absorption performance.

[0028] The durable hydrophilic fibers contained in the first fiber layer 211 and the general hydrophilic fibers contained in the second fiber layer 212 are defined based on the results of the following hydrophilicity test. (Hydrophilicity test) Using hydrophilic fibers, basis weight 20 g / m² 2 An air-through nonwoven fabric is prepared, and 100 μL of 0.9% saline solution is dropped onto the same location on the obtained air-through nonwoven fabric every 30 seconds. The number of drops in which the dropped saline solution does not penetrate the air-through nonwoven fabric but forms droplets on the air-through nonwoven fabric is then measured. Hydrophilic fibers contained in air-through nonwoven fabrics with a drop count of 1 to 8 are defined as general hydrophilic fibers, and hydrophilic fibers contained in air-through nonwoven fabrics with a drop count of 9 or more are defined as durable hydrophilic fibers.

[0029] Durable hydrophilic fibers and general hydrophilic fibers are obtained by treating natural fibers or synthetic fibers with a predetermined hydrophilic treatment agent to impart a predetermined level of hydrophilicity. Here, treatment with a hydrophilic treatment agent includes, for example, a method of adding a hydrophilic treatment agent to a synthetic resin and spinning the synthetic resin; a method of immersing natural fibers or synthetic resins in a hydrophilic treatment solution obtained by dissolving or dispersing a hydrophilic treatment agent in a suitable solvent such as water, an organic solvent, or a mixed solvent of water and an organic solvent for a predetermined time and drying; and a method of applying a hydrophilic treatment agent or a hydrophilic treatment solution obtained by dissolving or dispersing a hydrophilic treatment agent in a suitable solvent such as water, an organic solvent, or a mixed solvent of water and an organic solvent to natural fibers or synthetic resins. Natural fibers are not particularly limited, but examples include cotton fibers and cellulose fibers. Synthetic fibers are not particularly limited, but examples include polyester fibers such as polyester fibers and polyethylene terephthalate (PET) fibers, and polyolefin fibers such as polyethylene fibers and polypropylene fibers. In addition, fibers spun from hydrophilic resins described later may also be used.

[0030] Examples of hydrophilic treatment agents used for general hydrophilic fibers include anionic surfactants such as sodium lauryl sulfonate and potassium lauryl phosphate. Among these, potassium lauryl phosphate is preferred from the viewpoint of hydrophilicity. Examples of treatment agents used for durable hydrophilic fibers include castor oil derivatives. Specific examples of castor oil derivatives include polyoxyalkylene chain adducts of natural oils such as castor oil and hydrogenated castor oil, or their fatty acid esters, polyoxyethylene stearyl ether, and water-soluble modified silicone. Among these, hydrogenated polyoxyethylene castor oil is preferred from the viewpoint of productivity.

[0031] The antibacterial fibers included in the second fiber layer 212 are not particularly limited as long as they have antibacterial properties and are suitable as a material for the absorbent article 1, but fibers with antibacterial metal ions supported internally and / or on the surface are preferred. Metal compounds containing metal ions may also be used by supporting them on an inorganic porous body. Examples of support methods include physical adsorption, chemical adsorption, ion exchange, vapor deposition, surface thin film formation, and mechanical support. The antibacterial metal ions are not particularly limited and include, for example, ions such as silver, copper, and zinc. Among these, silver ions, which exhibit antibacterial effects even in trace amounts, are preferred. Examples of inorganic porous bodies include zeolite, hydrotalcite, hydroxyapatite, clay minerals, alumina, silica, and bentonite. Antibacterial organic compounds (antibacterial agents) may also be used. The antibacterial agents are not particularly limited, but examples include hinokitiol, cetylpyridinium chloride, chlorhexidine gluconate, isopropylmethylphenol, benzalkonium chloride, chlorhexidine hydrochloride, benzethonium chloride, and triclosan. Antibacterial metal ions and antibacterial agents can each be used individually or in combination of two or more. Hereinafter, antibacterial metal ions and antibacterial agents may be collectively referred to as antibacterial components.

[0032] Antibacterial fibers can be produced by methods such as immersing and drying fibers in an antibacterial solution, which is a solution or dispersion containing one or more antibacterial components, to fix the antibacterial components to the fiber surface; applying and drying an antibacterial solution to the fiber surface to fix the antibacterial components to the fiber surface; or adding one or more antibacterial components to a molten synthetic resin and then spinning the synthetic resin. Examples of fibers include cellulose fibers and synthetic fibers. Specific examples of cellulose fibers include natural cellulose fibers such as pulp fibers, cotton fibers, hemp fibers, and kenaf fibers; chemically modified cellulose fibers such as ethylcellulose-containing fibers, hydroxyethylcellulose-containing fibers, hydroxypropylcellulose-containing fibers, methylcellulose-containing fibers, ethylhydroxyethylcellulose-containing fibers, and carboxymethylcellulose-containing fibers; and regenerated cellulose fibers. Examples of synthetic fibers include synthetic fibers spun from hydrophilic resins such as polyacrylamide, polyvinyl alcohol, cross-linked polyvinyl alcohol, chitin, chitosan, ethylene vinyl acetate copolymer, and polyvinyl formal; polyester fibers such as polyester fibers and polyethylene terephthalate (PET) fibers; and polyolefin fibers such as polyethylene fibers and polypropylene fibers. Furthermore, water, organic solvents, and mixed solvents of water and organic solvents can be appropriately selected and used as solvents for the antibacterial solution.

[0033] The basis weight of the durable hydrophilic fibers in the first fiber layer 211 is, for example, 3 g / m². 2 More than 15g / m 2 The following is preferred: 5 g / m² 2 More than 10g / m 2 From the viewpoint of absorption rate during urination and liquid return, a more preferable value is 7 g / m². 2 More than 9g / m 2 The following applies: The basis weight of the durable hydrophilic fiber is 3 g / m². 2 Smaller particles may result in a slower absorption rate, so 15g / m² is recommended. 2 If the size is larger, there is a risk that the amount of fluid returning to the body will increase.

[0034] The basis weight of the general hydrophilic fibers in the second fiber layer 212 is not particularly limited, but for example, 7 g / m² 2 More than 25g / m 2 The following is preferable: 12 g / m² 2 More than 21g / m 2 From the perspective of liquid return, a more preferable concentration is 14 g / m². 2 More than 18g / m 2 The following applies: The basis weight of the general hydrophilic fiber is 7 g / m². 2 If the amount is smaller than 25g / m², there is a risk of increased liquid return. 2 If the amount is larger, the antibacterial properties of the top sheet 21 may decrease. The basis weight of the antibacterial fibers in the second fiber layer 212 is, for example, 1 g / m². 2 More than 6g / m 2 The following is preferable: 2 g / m 2 More than 4g / m 2 The following applies: The basis weight of the antibacterial fiber is 1 g / m². 2 Smaller sizes may reduce antibacterial properties, so 6g / m 2 If the metal is larger, the metal ions released by bodily fluids may affect the skin.

[0035] The overall basis weight of the top sheet 21 is, for example, 15 g / m². 2 More than 40g / m 2 The following is preferable: 19 g / m² 2 More than 35g / m 2 More preferably 18 g / m² 2 More than 30g / m 2 The following applies: The basis weight of Top Sheet 21 is 15 g / m². 2 Smaller sizes may increase the risk of liquid backflow, so 40g / m 2 If it is larger, it tends to feel hard when it comes into contact with the skin. There are no particular restrictions on the shape of the top sheet 21, but it should be shaped to cover all or part of the skin-facing side of the absorbent 22, which is necessary to guide bodily fluids to the absorbent 22 to prevent leakage.

[0036] <Absorbent> The absorbent material 22 has a longitudinal dimension (maximum length) that is, for example, in the range of 100 mm to 800 mm, 150 mm to 500 mm, or 270 mm to 500 mm. The width dimension (maximum width) of the absorbent material 22 is, for example, in the range of 50 mm to 500 mm, 60 mm to 400 mm, or 70 mm to 105 mm. Furthermore, if the plan view shape of the absorbent material 22 is hourglass-shaped, the longitudinal dimension is in the range of 180 mm to 480 mm, the width dimensions of the ventral and dorsal parts that come into contact with the wearer's abdomen and back are both in the range of 60 mm to 160 mm, and the width dimension of the crotch part that comes into contact with the wearer's groin is in the range of 50 mm to 140 mm. The entire surface or part of the absorbent material 22 may be embossed. Examples of the planar shape of the absorber 22 include an hourglass shape, an I-shape, a rectangle, a rounded quadrilateral with rounded corners, and an oval.

[0037] In this embodiment, the absorbent material 22 is interposed between the absorbent material covering sheet 50 and the back sheet 23, and absorbs and retains bodily fluids that have permeated through the top sheet 21, for example. The absorbent material 22 contains, for example, absorbent fibers and superabsorbent polymer (hereinafter also referred to as "SAP") as an absorbent base material.

[0038] (Absorbent fiber) Absorbent fibers are generally not limited to those used in absorbent articles such as sanitary napkins, disposable diapers, and incontinence pads. Examples include fluff pulp, cotton, rayon, acetate, tissue, absorbent paper, and hydrophilic nonwoven fabrics. Among these, fluff pulp is preferred from the viewpoint of absorbency. Examples of fluff pulp include wood pulp (for example, bleached kraft pulp from coniferous trees such as Southern pine and Douglas fir (N-BKP)), synthetic fibers, resin fibers, and cotton-like defibrated products of non-wood pulp. When fluff pulp is used as the absorbent fiber in the absorbent body 22, the basis weight of the absorbent fiber is, for example, 100 g / m². 2 More than 800g / m 2 The following range or 325g / m² 2 More than 615g / m 2The range is as follows. This allows for the absorption of more bodily fluids without compromising the feel against the skin.

[0039] (Highly absorbent polymer) There are no particular limitations on the superabsorbent polymer as long as it can absorb bodily fluids and prevent backflow. Examples include polyacrylates, polyaspartates, (starch-acrylic acid) graft copolymers, (acrylic acid-vinyl alcohol) copolymers, (isobutylene-maleic anhydride) copolymers, and their saponifies. Among these, polyacrylates are preferred from the viewpoint of absorption per unit weight, alkali metal polyacrylates are more preferred, and sodium polyacrylate is even more preferred. The superabsorbent polymer can be used alone or in combination of two or more.

[0040] Superabsorbent polymers are used in various forms, such as particulate or fibrous, but are preferably used in particulate form for ease of handling. In this case, by avoiding the use of superabsorbent polymers in the form of fine powder, which have poor fluidity as a powder, and instead using superabsorbent polymers with a medium particle size, the basic performance related to absorption can be improved, and the rough texture caused by the hardening of the absorbent material 22 can be reduced. The medium particle size of the superabsorbent polymer is, for example, in the range of 50 μm to 600 μm or 100 μm to 500 μm.

[0041] The basis weight of SAP in absorbent material 22 is, for example, 240 g / m². 2 More than 450g / m 2 The following ranges, or 245g / m² 2 More than 445g / m 2 The range is as follows. By keeping the basis weight of the SAP within the aforementioned numerical range, gel blocking in the absorbent material 22 can be prevented, and a large amount of bodily fluids can be absorbed by the absorbent material 22. Furthermore, in the absorbent material 22, the ratio of the weight of the superabsorbent polymer to the total weight of the absorbent material 22, i.e., weight of superabsorbent polymer / total weight of absorbent material 22 × 100 (%), is, for example, in the range of 40% by weight or more, or in the range of 40% by weight or more and 70% by weight or less.

[0042] In the absorbent body 22, the form of the absorbent fibers and SAP may be one in which SAP particles are mixed into absorbent fibers, or it may be an SAP sheet in which SAP particles are fixed between absorbent fibers.

[0043] <Back seat> The backsheet 23 can be formed using a base material that is impermeable to liquid so that the bodily fluids held by the absorbent 22 do not wet the clothing. Examples of such base materials include resin films and composite sheets which are laminates of resin films and nonwoven fabrics. The nonwoven fabric used in the composite sheet is not particularly limited in its manufacturing method and can include single-layer nonwoven fabrics such as spunbond nonwoven fabrics and meltblown nonwoven fabrics, composite nonwoven fabrics such as spunbond nonwoven fabric / meltblown nonwoven fabric laminates and spunbond nonwoven fabric / meltblown nonwoven fabric / spunbond nonwoven fabric laminates, and composite materials thereof. Examples of resin films include polyester, polyvinyl alcohol, polyethylene, polypropylene, and composite films of polyethylene and polypropylene.

[0044] The basis weight of backsheet 23 is, for example, 15 g / m², considering strength and processability. 2 More than 60g / m 2 The following range applies. Furthermore, to prevent stuffiness during wear, it is preferable that the back sheet 23 be breathable. To provide breathability to the back sheet 23, for example, a filler can be compounded into the resin film of the base material, or the back sheet 23 can be embossed. Calcium carbonate can be used as a filler, and the compounding method can be any known method without limitation.

[0045] <3D Gathering> The three-dimensional gathers 24 are fixed to the skin-facing side of the top sheet 21 along the longitudinal direction of the absorbent article 1 near both ends in the width direction of the absorbent article 1, for example, to prevent lateral leakage of bodily fluids excreted by the wearer of the absorbent article 1. The three-dimensional gathers 24 include an elastic stretchable member 24a and a water-repellent and / or waterproof sheet member 24b.

[0046] The elastic stretchable member 24a is arranged along the longitudinal direction near the free end (other end) of the sheet member 24b, providing the free end with uprightness and allowing the free end and its vicinity to deform to conform to the wearer's body shape. In this embodiment, one end (fixed end) in the width direction of the sheet member 24b is fixed near both ends in the width direction of the skin-facing side of the back sheet 23, a portion in the width direction is fixed near both ends in the width direction of the skin-facing side of the top sheet 21, and the other end in the width direction is an upright free end. The fixing position of the fixed end (one end in the width direction) of the sheet member 24b is not limited to this embodiment, and examples include the non-skin-facing side of the back sheet 23, near both ends in the width direction of the skin-facing or non-skin-facing side of the joint between all or part of the edges of the top sheet 21 containing the absorbent body 22 and the back sheet 23, and near both ends in the width direction of the skin-facing side of the top sheet 21.

[0047] The sheet member 24b is a water-repellent and / or waterproof sheet, and is made of, for example, a nonwoven fabric. The nonwoven fabric for the first sheet member can be any water-repellent and / or waterproof (liquid-impermeable) nonwoven fabric formed from hydrophobic fibers, without any particular limitations. Examples include spunbond nonwoven fabric, meltblown nonwoven fabric, and composite nonwoven fabric (SMS nonwoven fabric) which is a laminate of spunbond nonwoven fabric / meltblown nonwoven fabric / spunbond nonwoven fabric. The basis weight of the sheet member 24b is, for example, 13 g / m². 2 More than 20g / m 2 The range is as follows. As the elastic stretchable member 24a, thread-like, string-like, or strip-like materials made of natural rubber, synthetic rubber, polyurethane, etc., can be used as appropriate.

[0048] <Absorbent body of the second embodiment> As shown in Figure 4, the absorbent body 26 is based on a top sheet 21, an absorbent 22 wrapped in an absorbent covering sheet 25, and a back sheet 23, which are laminated from the skin side to the non-skin side. If necessary, the top sheet 21 has a pair of three-dimensional gathers 24 extending in the longitudinal direction near both ends in the width direction on the skin side. The absorbent body 26 has the same configuration as the absorbent body 20, except that the absorbent 22 is wrapped in an absorbent covering sheet 25. It is a modified version of the absorbent body 20, having undergone certain modifications. In the absorbent body 26, components common to the absorbent body 20 are given the same reference numerals, and their descriptions are omitted.

[0049] The absorbent covering sheet 25 of this embodiment is a sheet member that wraps the entire absorbent 22 by a so-called C-fold, where the absorbent 22 is placed or adhered to the center of the width direction of the absorbent surface on its skin side, and the ends near both sides in the width direction are folded and overlapped above the skin side of the absorbent 22. The absorbent covering sheet 25 has functions such as preventing SAP from falling off the absorbent 22, improving the strength of the absorbent 22 by maintaining the shape of the absorbent 22 and increasing the amount of bodily fluid absorbed, and uniformly supplying bodily fluid to the skin side of the absorbent 22. The base material of the absorbent covering sheet 25 can be any hydrophilic material, and tissue or absorbent paper containing pulp fibers is particularly preferred, but hydrophilic nonwoven fabrics such as airlaid nonwoven fabric may also be used. In addition to the C-fold arrangement, the absorbent covering sheet 25 may also be placed on the skin side and / or non-skin side of the absorbent 22.

[0050] <Second row seats> An example of a modification common to the absorbent body 20 and absorbent body 26 is a second sheet (not shown). The second sheet is, for example, placed between the top sheet 21 and the absorbent body 22 or the absorbent body covering sheet 25, and improves the liquid diffusion of the absorbent body 20 and absorbent body 26, and suppresses the return of bodily fluids from the absorbent body 22. As the second sheet, any liquid-diffusive substrate can be used without particular limitation, as the rate of permeation of bodily fluids is faster than that of the top sheet 22 and allows for rapid diffusion of bodily fluids into the absorbent body 22. Examples of such substrates include hydrophilic nonwoven fabrics, and among these, air-through nonwoven fabrics are preferred.

[0051] The second sheet has a thickness of, for example, 0.1 mm or more, and a basis weight of, for example, 10 g / m². 2 More than 60g / m 2 The following ranges, or 15g / m² 2 More than 40g / m 2 The following ranges apply: Thickness less than 0.1 mm, or basis weight 10 g / m². 2 Less than 60g / m² 2 If the size is larger, the body fluids tend not to spread sufficiently across the entire skin-facing surface of the absorbent 22. Also, while there are no particular restrictions on the shape of the second sheet, it is preferable that it be shaped in such a way that it can completely cover the surface of the absorbent 22 so that the body fluids spread uniformly across the absorbent 22.

[0052] The ratio of the basis weight of the top sheet 21 to the second sheet (percentage, basis weight of the second sheet / basis weight of the top sheet 21) is, for example, in the range of 50% to 130% or 50% to 100%. By setting the basis weight ratio to 50% to 130%, the liquid diffusion and liquid permeability when bodily fluids permeate from the top sheet 21 to the second sheet are improved, and liquid return from the second sheet to the top sheet 21 is further suppressed.

[0053] <Method for manufacturing the absorbent body> The absorbent body 20 can be manufactured by known manufacturing methods, but examples of such manufacturing methods include the steps of overlapping the top sheet 21, absorbent material 22, and back sheet 23 in the thickness direction and placing the absorbent material 22 between the top sheet 21 and the back sheet 23; fixing the edges of the top sheet 21 and the back sheet 23 to part or all of their circumference using hot melt adhesive, heat embossing, ultrasonic embossing, high-frequency embossing, etc.; and installing three-dimensional gathers 24 at predetermined positions on the back sheet 23 and the top sheet 21. The absorbent body 26 can be manufactured in the same manner as the absorbent body 20, except that the absorbent material 22 is wrapped in an absorbent material covering sheet 25. Leg gathers, waist gathers, side flaps, etc. may be provided on the absorbent bodies 20 and 26 as needed.

[0054] <Method for manufacturing absorbent pant-type articles> There are no particular restrictions on the manufacturing method of the pant-type absorbent article 1, and conventionally known methods can be used. For example, the pant-type absorbent article 1 can be obtained by following these steps in order: placing and joining the above-mentioned elastic stretch members between the outer nonwoven fabric sheets 301, 401, 501 and the inner nonwoven fabric sheets 302, 402, 502 at the periphery of the leg opening 12 of the front side portion 13, the rear side portion 15, and the crotch portion 14; arranging the absorbent body 20 (or absorbent body 26) on the body side of the outer body; and joining the widthwise side edges of the front side portion 13 and the widthwise side edges of the rear side portion 14.

[0055] Although the present invention has been described above using embodiments, it goes without saying that the technical scope of the present invention is not limited to the scope described in the above embodiments and examples. It will be obvious to those skilled in the art that various modifications or improvements can be made to the above embodiments. Furthermore, it is clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention. [Examples]

[0056] The present invention will be described in detail below with reference to examples. However, the present invention is not limited in any way to the examples shown below.

[0057] (Production of general hydrophilic fibers and water-resistant hydrophilic fibers) A 2.0% by weight aqueous solution of potassium lauryl phosphate (hydrophilization solution A) was prepared. Polyethylene fibers were immersed in this hydrophilization solution A for 60 minutes at room temperature, and then dried with hot air at 120°C to produce general hydrophilic fibers that required 4 drops in the hydrophilicity test described above (see below). In addition, a 1.0% by weight aqueous solution of polyoxyethylene stearyl ether (hydrophilization solution B) was prepared. Polyethylene fibers were immersed in this hydrophilization solution B for 60 minutes at room temperature, and then dried with hot air at 120°C to produce durable hydrophilic fibers that required 9 drops in the hydrophilicity test described above.

[0058] (Production of antibacterial fibers) Polyethylene fibers were immersed in a 4.0 wt% aqueous solution of sodium metasilicate. A fixed amount of a 3.0 wt% aqueous solution of sodium aluminate and a silver ion-supported zeolite were then added, and the mixture was immersed at 90°C for 3 hours to produce silver ion-supported zeolite-supported polyethylene fibers. The silver ion load of the obtained polyethylene fibers was 0.002 wt%.

[0059] (Creating the top sheet) Using the general hydrophilic fibers (fiber thickness 2.6 dtex, fiber length 50 mm), durable hydrophilic fibers (fiber thickness 2.0 dtex, fiber length 51 mm), and antibacterial fibers (fiber thickness 2.2 dtex, fiber length 51 mm) obtained above, a two-layer air-through nonwoven fabric was prepared, with durable hydrophilic fibers in the first fiber layer and general hydrophilic fibers and antibacterial fibers in the second fiber layer, and this was used as the top sheet. Its composition is shown in Table 1.

[0060] (Creation of absorbent pants) The absorbent material is formed by mixing 9.0g of SAP into 8.0g of the base material, which is fluff pulp, and the top sheet is the two-layer type air-through nonwoven fabric obtained above (basis weight 20g / m²). 2 ), and a breathable polyethylene sheet (basis weight 32g / m²) as a liquid-impermeable backsheet. 2 ), and composite nonwoven fabrics (basis weight 15g / m²) which are laminates of spunbond nonwoven fabric / meltblown nonwoven fabric / spunbond nonwoven fabric as three-dimensional gathers. 2 ), and tissue (basis weight 15g / m²) as a carrier sheet covering the skin-side and non-skin-side of the absorbent core. 2 ), spunbond nonwoven fabric (basis weight 17g / m²) as the outer nonwoven fabric sheet and the inner nonwoven fabric sheet. 2 Examples 1-4 and Comparative Examples 1-3 were manufactured using string-shaped natural rubber as the elastic stretchable member, with the dimensions of the absorbent body being 350 mm in the longitudinal direction and 180 mm in width, and the dimensions of the pant-type absorbent article being 400 mm in the longitudinal direction and 200 mm in width.

[0061] The following evaluation tests were conducted on the pant-type absorbent articles of Examples 1-4 and Comparative Examples 1-3. The results are shown in Table 1. (Absorption rate) Bottom area 16.8cm 2 A measuring jig with a cylindrical shape, a hole with an inner diameter of 19 mm in the center, and a weight of 755.6 g, was placed on the center of the absorbent body in both its longitudinal and width directions. 20 ml of physiological saline solution was dropped through the hole at the top, and the time (in seconds) was measured from the moment the physiological saline solution came into contact with the absorbent body until the liquid was completely absorbed into the circumference of the central circle of the jig. (Liquid return property) With the absorbent body's top sheet facing upwards, pour 120 ml of physiological saline solution towards the center of the absorbent body. After letting it stand for 10 minutes, place a filter paper (ADVANTEC No. 2 filter paper, 55 mm in diameter) whose weight has been measured in advance onto the absorption area of ​​the physiological saline solution, and then apply 35 kgf / cm² to it. 2 A weight was placed on the filter paper, and after 30 seconds, the weight of the filter paper was measured. The difference in weight of the filter paper was defined as the amount of liquid return (g), and the liquid return performance was evaluated. A smaller amount of liquid return indicates better liquid return performance. (antibacterial) Antibacterial properties were assessed using the top sheet, following the JIS L 1902 method. Products with an antibacterial activity value of 3 or higher, based on the results of a standard cloth (cotton cloth) for Staphylococcus aureus, were marked with ○, those with a value of 2 or higher but less than 3 were marked with △, and those with a value less than 2 were marked with ×.

[0062] [Table 1]

[0063] The results in Table 1 show that the absorbent bodies of Examples 1-4 exhibit excellent absorption rate, liquid return, and antibacterial properties. On the other hand, the antibacterial fiber was 3 g / m 2 Comparative Example 1, which included the specified material, demonstrated antibacterial properties, but exhibited poor water absorption and liquid return rates. Comparative Example 2, which used only antibacterial fibers for the second fiber layer, showed poor antibacterial properties and a slow absorption rate. Furthermore, Comparative Example 3 did not exhibit any antibacterial properties. Therefore, according to the present invention, it is possible to provide a pant-type absorbent article using an absorbent body that has excellent liquid permeability and excellent return properties of body fluids, and even when body fluids remain on the top sheet, it has excellent antibacterial properties. [Explanation of Symbols]

[0064] 1. Absorbent pad 11 Waist opening 12 leg openings 13 Ventral part 14 Crotch 15 Dorsal part 20, 26 Absorbent body 21 Top Sheet 211 First fiber layer 212 Second Fiber Layer 22 absorbent 23 Backseat 24 Three-dimensional gathers 24a Elastic stretchable member 24b Sheet material 25 Absorbent covering sheet 30 Ventral band member 301 Outer nonwoven fabric sheet (ventral band component) 302 Interior nonwoven fabric sheet (ventral band component) 40 Back band member 401 Outer nonwoven fabric sheet (back side band component) 402 Interior nonwoven fabric sheet (back side band material) 50 Crotch band member 501 Outer nonwoven fabric sheet (crotch band component) 502 Interior nonwoven fabric sheet (crotch band component)

Claims

1. A pant-type absorbent article comprising: an abdominal band member disposed on the abdominal side of the wearer; a back band member disposed on the back of the wearer; a crotch band member interposed between the abdominal band member and the back band member and disposed on the crotch of the wearer to support the absorbent body; and a waist opening and leg openings formed by joining the widthwise ends of the abdominal band member and the widthwise ends of the back band member, The absorbent body comprises a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent material disposed between the top sheet and the back sheet, with both longitudinal ends joined to the skin surface of the ventral band member and the skin surface of the dorsal band member, respectively. The ventral band member, the dorsal band member, and the crotch band member each comprise an inner nonwoven fabric sheet located on the skin side, an outer nonwoven fabric sheet located on the non-skin side, and a plurality of elastic stretch members positioned between the inner nonwoven fabric sheet and the outer nonwoven fabric sheet. The top sheet comprises a first fiber layer containing durable hydrophilic fibers, and a second fiber layer adjacent to the non-skin-contacting surface of the first fiber layer, containing general hydrophilic fibers and antibacterial fibers, wherein the first fiber layer and the second fiber layer are overlapped in the thickness direction, the skin-contacting surface of the first fiber layer constitutes the skin-contacting surface of the top sheet, and the non-skin-contacting surface of the second fiber layer constitutes the non-skin-contacting surface of the top sheet. The aforementioned top sheet is an air-through nonwoven fabric, The basis weight of the durable hydrophilic fibers in the first fiber layer is 8 g / m². ２ 12g / m or more ２ The basis weight of the general hydrophilic fibers in the second fiber layer is 10 g / m². ２ 18g / m or more ２ The following applies, and the basis weight of the antibacterial fiber is 2 g / m². ２ 4g / m or more ２ The following: The aforementioned antibacterial fibers are not included in the first fiber layer, characterized in that the absorbent pant-type article. However, the above general hydrophilic fiber and the above durable hydrophilic fiber have a basis weight of 20 g / m² including the fiber. ２ Hydrophilicity is defined by a hydrophilicity evaluation that is observed when 100 μL of 0.9% saline solution is dropped onto the same position on the air-through nonwoven fabric every 30 seconds, and the number of drops at which the dropped saline solution does not penetrate the air-through nonwoven fabric but forms droplets on the air-through nonwoven fabric is observed. Fibers contained in the air-through nonwoven fabric with a hydrophilicity evaluation of 1 to 8 times are defined as general hydrophilic fibers, and fibers contained in the air-through nonwoven fabric with a hydrophilicity evaluation of 9 or more times are defined as durable hydrophilic fibers.

2. The basis weight of the topsheet is 18 g / m ２ or more and 30 g / m ２ or less, and the pant-type absorbent article according to claim 1, characterized in that.

3. The pants-type absorbent article according to claim 1 or claim 2, wherein the absorbent body further comprises an absorbent covering sheet disposed between the top sheet and the absorbent body, and the absorbent covering sheet contains pulp fibers.

4. The pant-type absorbent article according to any one of claims 1 to 3, characterized in that the durable hydrophilic fibers contained in the first fiber layer are treated with a castor oil derivative, and the general hydrophilic fibers contained in the second fiber layer are treated with an anionic surfactant.

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