Absorbent article

Abstract

Provided is an absorbent article which is not susceptible to structural restrictions, is capable of suppressing odor of urine, and is not susceptible to conspicuous color of urine. The absorbent article according to the present invention contains an adsorbent that adsorbs the odor and color of urine. The adsorbent is characterized in that the L * value of the L * a * b * color system of the adsorbent is 10 or more, and the adsorbent has pores having a pore diameter of 1.5 nm to 2.0 nm at a volume of 0.006 mL / g or more and micropores having a pore diameter of 0.3 nm to 0.8 nm at a volume of 0.050 mL / g or more.

Description

Technical Field

[0001] The present invention relates to an absorbent article that absorbs at least urine, such as an incontinence pad, a disposable diaper, and a sanitary napkin. Background Art

[0002] Absorbent articles such as incontinence pads, disposable diapers, and sanitary napkins are used to absorb and retain excreta such as urine, feces, and menstrual blood discharged from the wearer. Therefore, absorbent articles are required to reduce the odor of excreta.

[0003] As one of the methods for reducing the odor of excrement in absorbent articles, an adsorption method using a physical adsorption type deodorant such as activated carbon is known. For example, Patent Document 1 discloses a composition in the form of bound particles composed of a coagulated mixture of an odor control agent, white particles, and a water-soluble or water-dispersible binder substance, wherein the odor control agent is composed of black carbon particles, and the white particles are selected from the group consisting of a white odor control agent and a white masking substance. The composition of Patent Document 1 is used as an odor control agent for absorbent articles. According to the composition, not only can malodor molecules be adsorbed, but the color of the black carbon particles can also be made inconspicuous.

[0004] In addition, Patent Document 2 discloses an absorbent article having an absorbent body, wherein the absorbent body has an absorbent core containing a water-absorbent polymer, an inner sheet disposed on the skin-opposing side of the absorbent core, and an outer sheet disposed on the skin-opposing side of the inner sheet. In the absorbent article of Patent Document 2, the inner sheet carries activated carbon particles and is colored gray, and the outer sheet is colored gray, and the L* value of the outer sheet in the L*a*b* color system is larger than the L* value of the inner sheet. According to this absorbent article, the odor of urine can be suppressed, and the color of urine can be made less conspicuous.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Publication No. 5-503452

[0008] Patent Document 2: Japanese Patent Application Publication No. 2014-68681 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] In an absorbent article using the composition of Patent Document 1, even if the black carbon particles can be made less conspicuous by white particles, the color of urine will be conspicuous due to the visual contrast with white, which may give the user a sense of discomfort such as a lack of cleanliness.

[0011] Furthermore, in the absorbent article of Patent Document 2, even if the color of urine can be made less conspicuous, since the inner sheet and the outer sheet colored in specific colors are indispensable, there is a problem that structural restrictions are imposed on the absorbent article.

[0012] The present invention has been made in view of these problems, and an object of the present invention is to provide an absorbent article which is less likely to be restricted in structure and which can suppress the odor of urine and make the color of urine less conspicuous.

[0013] Solutions for solving problems

[0014] The inventors of the present application have conducted intensive research to achieve the above-mentioned purpose, and as a result, have found that an adsorbent having an L* value of 10 or more in the L*a*b* color system and having pores and micropores of a specific pore size in a volume of a specific volume or more can suppress the odor of urine and make the color of urine less noticeable. The present invention has been completed based on this finding and includes the following aspects.

[0015] (Solution 1)

[0016] One embodiment of the present invention (Aspect 1) is an absorbent article comprising an adsorbent for absorbing the odor and color of urine, characterized in that:

[0017] The L* value of the L*a*b* color system of the above-mentioned adsorbent is greater than 10,

[0018] The adsorbent has pores with a pore diameter of 1.5 nm to 2.0 nm at a volume of 0.006 mL / g or more, and micropores with a pore diameter of 0.3 nm to 0.8 nm at a volume of 0.050 mL / g or more.

[0019] The absorbent article of the present embodiment 1 includes an adsorbent that absorbs the odor and color of urine. The adsorbent can adsorb and retain the pigment components of urine (such as urobilin, etc.) in pores with a pore size of 1.5nm to 2.0nm. In addition, the pigment components retained in the pores are surrounded and concealed by the portion other than the pores (non-pore portion) having a color with an L* value of 10 or more (gray to white) in the L*a*b* color system, and are therefore not easily visually recognized from the outside. The adsorbent can adsorb and retain a sufficient amount of pigment components by having the above-mentioned pores with a volume of 0.006mL / g or more.

[0020] Furthermore, the adsorbent can adsorb and hold odor components that cause urine odor in micropores with a pore size of 0.3 nm to 0.8 nm. The adsorbent can adsorb and hold a sufficient amount of odor components by having the micropores with a volume of 0.050 mL / g or more.

[0021] As described above, the adsorbent can suppress the odor of urine and make the color of urine less noticeable without requiring any other components (such as a concealing sheet, a shielding member, etc.) other than the adsorbent.

[0022] Therefore, the absorbent article of the first embodiment of the present invention including such an adsorbent is less likely to be restricted in structure, and can suppress the odor of urine and make the color of urine less noticeable. In addition, "white" has a high effect of leaving an impression of cleanliness, so such an absorbent article has the following advantages: it is white before use and does not change after use, which can give the user a positive impression of cleanliness.

[0023] (Solution 2)

[0024] Another aspect (aspect 2) of the present invention is the absorbent article according to aspect 1, wherein the adsorbent is composed of a plurality of particles having a particle size of 500 μm or less.

[0025] In the second aspect, the adsorbent is composed of a plurality of particles having a particle size of 500 μm or less. Thus, in the absorbent article of the second aspect, the surface area of ​​the adsorbent that urine can contact is large, and the odor and color of urine can be adsorbed at a more excellent adsorption rate.

[0026] (Solution 3)

[0027] Another scheme (Scheme 3) of the present invention is characterized in that, based on the absorbent article of the above-mentioned Scheme 1 or Scheme 2, the above-mentioned adsorbent contains at least one porous substance selected from the group consisting of activated carbon, silica gel, activated alumina, activated clay, synthetic zeolite, and synthetic polymer.

[0028] The porous material has the advantages that it can stably exert an adsorption effect and the pore sizes of fine and micro pores can be easily controlled. Therefore, the absorbent article of the third embodiment can more reliably adsorb the odor and color of urine.

[0029] (Solution 4)

[0030] Another scheme (Scheme 4) of the present invention is characterized in that, based on the absorbent article of the above-mentioned Scheme 3, in the above-mentioned adsorbent, the above-mentioned porous substance is covered with at least one white inorganic substance selected from titanium oxide, calcium carbonate, zinc oxide, barium sulfate, magnesium oxide, kaolin and talc.

[0031] In the fourth embodiment, the adsorbent is composed of the porous substance and the white inorganic substance covering the porous substance. Since the white inorganic substance has excellent concealing power, the pigment component retained in the pores of the adsorbent (i.e., the pores of the porous substance) can be more difficult to visually identify from the outside. As a result, the absorbent article of the fourth embodiment can make the color of urine less conspicuous. In addition, the absorbent article has the advantage of being able to give the user a further positive impression of cleanliness.

[0032] (Scheme 5)

[0033] According to still another aspect (aspect 5) of the present invention, in the absorbent article of aspect 4, the white inorganic substance is a plurality of particles.

[0034] In the fifth embodiment, the white inorganic substance covering the porous substance is a plurality of particles. Thus, the adsorbent can make the odor component and the pigment component pass through the gaps between the particles of the white inorganic substance and be adsorbed and retained in the pores and micropores of the porous substance. That is, the adsorbent does not cause any hindrance to the adsorption of the odor component and the pigment component, and the pigment component adsorbed and retained in the pores of the porous substance can be more difficult to visually identify from the outside. Therefore, the absorbent article of the fifth embodiment can more reliably suppress the odor of urine and make the color of urine less conspicuous.

[0035] (Scheme 6)

[0036] According to another aspect (aspect 6) of the present invention, in addition to the absorbent article of any one of aspects 1 to 5, the absorbent article includes an absorbent body, and the adsorbent is disposed at least one of a surface and an interior of the absorbent body.

[0037] In the absorbent article of the sixth aspect, since the adsorbent is disposed at a position that is likely to come into contact with urine, the adsorbent can more reliably suppress the odor of urine and make the color of urine less noticeable.

[0038] (Scheme 7)

[0039] According to another aspect (aspect 7) of the present invention, in the absorbent article of aspect 6, the absorbent body includes an absorbent core containing a superabsorbent polymer, and the adsorbent is arranged in contact with the superabsorbent polymer.

[0040] In the absorbent article of the seventh aspect, since the adsorbent is disposed at a position more likely to come into contact with urine, the adsorbent can more reliably suppress the odor of urine and make the color of urine less noticeable.

[0041] (Scheme 8)

[0042] According to another aspect (aspect 8) of the present invention, in the absorbent article of any one of aspects 1 to 7, the mass ratio of the adsorbent contained in the absorbent article is 0.1 mass % or more of the total mass of the absorbent article.

[0043] Since the absorbent article of the eighth aspect contains the above-mentioned adsorbent in a predetermined amount or more, the adsorbent can more reliably suppress the odor of urine and make the color of urine less noticeable.

[0044] (Scheme 9)

[0045] Another embodiment of the present invention (Aspect 9) is a method for treating urine, comprising bringing urine into contact with an adsorbent that absorbs the odor and color of urine, wherein:

[0046] The L* value of the L*a*b* color system of the above-mentioned adsorbent is greater than 10,

[0047] The adsorbent has pores with a pore diameter of 1.5 nm to 2.0 nm at a volume of 0.006 mL / g or more, and micropores with a pore diameter of 0.3 nm to 0.8 nm at a volume of 0.050 mL / g or more.

[0048] The method for treating urine of the ninth aspect includes bringing urine into contact with an adsorbent that absorbs the odor and color of urine. As described above, the adsorbent can suppress the odor of urine and make the color of urine less noticeable without requiring other components.

[0049] Therefore, the urine treatment method of the present embodiment 9 using such an adsorbent is less likely to be restricted in structure, and can suppress the odor of urine and make the color of urine less conspicuous, so it can be applied to a wide range of uses requiring urine treatment, such as absorbent articles.

[0050] Effects of the Invention

[0051] According to the present invention, it is possible to provide an absorbent article that is less likely to be restricted in structure, can suppress the odor of urine, and can make the color of urine less noticeable. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a top view of the incontinence pad 1 according to one embodiment of the present invention.

[0053] Figure 2 yes Figure 1 End view of the incontinence pad 1 along line II-II'. DETAILED DESCRIPTION

[0054] Hereinafter, preferred embodiments of the absorbent article of the present invention will be described in detail with reference to the drawings.

[0055] In addition, in this specification, "the situation of observing an object (such as an incontinence pad, etc.) placed on a horizontal plane in a flat state unfolded from the upper side in the vertical direction (especially from the surface sheet side when the object is an incontinence pad) along the thickness direction of the object" is simply referred to as "looking down".

[0056] In addition, in this specification, in the thickness direction of the absorbent article, "the side that is relatively close to the skin surface of the wearer when the absorbent article is worn" is referred to as "skin-opposing surface side". Similarly, in the thickness direction of the absorbent article, "the side that is relatively close to the skin surface of the wearer when the absorbent article is worn" is referred to as "non-skin-opposing surface side".

[0057] [Incontinence pads]

[0058] One embodiment of the absorbent article of the present invention is an incontinence pad 1. Figure 1 As shown, the incontinence pad 1 has a length direction L and a width direction W when viewed from above, and has an oblong outer shape with both ends in the length direction L protruding in an arc shape toward the outer side in the length direction L. In addition, the outer shape of the absorbent article of the present invention is not limited to such a shape, and can adopt any shape (for example, rectangular, oval, hourglass, etc.) and size corresponding to various uses, usage forms, etc.

[0059] like Figure 2 As shown, the incontinence pad 1 has a liquid-permeable surface sheet 2 located on the skin-opposing side in the thickness direction T, a liquid-impermeable back sheet 3 located on the non-skin-opposing side, and a liquid-absorbing absorbent body 4 located therebetween as main components. In addition, in this embodiment, the incontinence pad 1 also has a pair of side sheets 5, 5 located on the skin-opposing side of the surface sheet 2 and extending along the length direction L at both ends in the width direction W.

[0060] In addition, the incontinence pad 1 includes an adsorbent for absorbing the odor and color of urine. In the present embodiment, the adsorbent is disposed inside the absorbent 4 of the incontinence pad 1. The adsorbent has a gray to white color with an L* value of 10 or more in the L*a*b* color system. Furthermore, the adsorbent has pores with a pore size of 1.5 nm to 2.0 nm in a volume of 0.006 mL / g or more, and has micropores with a pore size of 0.3 nm to 0.8 nm in a volume of 0.050 mL / g or more.

[0061] The adsorbent can adsorb and retain the pigment components (such as urobilin, etc.) of the urine discharged by the wearer into the incontinence pad 1 in the pores with a pore size of 1.5nm to 2.0nm. In addition, the pigment components retained in the pores are surrounded and concealed by the part (non-pore part) other than the pores with a gray to white color having an L* value of 10 or more in the L*a*b* color system, so it is not easy to visually identify from the outside. In addition, the adsorbent can adsorb and retain a sufficient amount of pigment components by having the above-mentioned pores with a volume of 0.006mL / g or more.

[0062] Furthermore, the adsorbent can adsorb and retain odor components (such as ammonia, hydrogen sulfide, methyl mercaptan, trimethylamine, etc.) that cause the odor of urine in micropores with a pore size of 0.3nm to 0.8nm. In addition, the adsorbent can adsorb and retain a sufficient amount of odor components by having the above-mentioned micropores with a volume of 0.050mL / g or more.

[0063] Therefore, even if no other components (such as concealing sheets and shielding members) other than the absorbent are provided in the incontinence pad 1, the absorbent can suppress the odor of urine and make the color of urine less noticeable.

[0064] Thus, the incontinence pad 1 including the absorbent can suppress the odor of urine and make the color of urine less noticeable without causing structural restrictions. In addition, the "white" color has a high effect of leaving a clean impression, so the incontinence pad 1 has the following advantages: it is white before use and does not change after use, which can give the user a positive impression of cleanliness.

[0065] Hereinafter, one embodiment of the adsorbent for absorbing the odor and color of urine used in the present invention will be described in more detail.

[0066] [Adsorbent]

[0067] In one embodiment of the present invention, the adsorbent is an adsorbent that absorbs the odor and color of urine, and has a color with an L* value of 10 or more in the L*a*b* color system, that is, a gray to white color. Furthermore, the adsorbent has pores with a pore size of 1.5nm to 2.0nm in a volume of 0.006mL / g or more, and has micropores with a pore size of 0.3nm to 0.8nm in a volume of 0.050mL / g or more. In the adsorbent, there is no particular limitation on the structure other than such an appearance color, pores and micropores. For example, the adsorbent may also be composed of a plurality of porous particles or porous fibers, and may also be composed of a porous molded object having a predetermined shape.

[0068] (Appearance color)

[0069] The appearance color of the adsorbent is not particularly limited as long as the L* value of the L*a*b* color system is 10 or more, but preferably the color has an L* value of 40 or more, more preferably the color has an L* value of 70 or more, and particularly preferably the color has an L* value of 80 or more (white color).

[0070] In addition, when the adsorbent is arranged at a position on the non-skin-opposing side of the surface sheet in the thickness direction of the absorbent article (e.g., on the surface or inside of the absorbent body), the appearance color of the adsorbent is preferably an appearance color in which the L* value of the surface on the skin-opposing side of the surface sheet is greater than 75. If the L* value of the surface on the skin-opposing side of the surface sheet is greater than 75, the wearer can have a clean impression when the absorbent article is first used.

[0071] <Method for measuring L* value of L*a*b* color system>

[0072] The L* value of the L*a*b* color system of the surface of the adsorbent and the surface sheet can be measured using a commercially available colorimeter in accordance with JIS Z 8722. As a commercially available colorimeter, for example, a colorimetric colorimeter ZE6000 manufactured by Nippon Denshoku Industries Co., Ltd. (standard white plate [X=93.19, Y=95.20, Z=112.28], reflection measurement diameter 30 mm) can be cited. In addition, the L* value is measured 5 times for each sample, and the average value is adopted.

[0073] (pores)

[0074] The pores (pore size 1.5nm~2.0nm) of the adsorbent can fully adsorb the pigment components of urine as long as the volume is more than 0.006mL / g. However, from the viewpoint of more reliably adsorbing the pigment components of urine, the volume of the pores of pore size 1.5nm~2.0nm is preferably more than 0.008mL / g, more preferably more than 0.010mL / g, and particularly preferably more than 0.040mL / g. In addition, the upper limit of the volume of the pores of pore size 1.5nm~2.0nm is not particularly limited, but from aspects such as the ease of manufacture, for example, it can be set to the volume below 1.5mL / g.

[0075] (Micropores)

[0076] As long as the volume of the micropores (pore diameter 0.3nm to 0.8nm) of the adsorbent is 0.050mL / g or more, it can fully adsorb and retain the odor components of urine. However, from the perspective of more reliably adsorbing and retaining the odor components of urine, the volume of the micropores with a pore diameter of 0.3nm to 0.8nm is preferably 0.060mL / g or more, more preferably 0.070mL / g or more, and particularly preferably 0.080mL / g or more. In addition, there is no particular upper limit on the volume of the pores with a pore diameter of 0.3nm to 0.8nm, but from the perspective of ease of manufacturing, it can be set to a volume of 1.5mL / g or less, for example.

[0077] In addition, it is preferred that the adsorbent has pores (macropores) with a pore size of 4.0 nm to 15 nm in addition to the above-mentioned pores and micropores. Such large pores can adsorb and retain protein components (such as albumin, etc.) contained in urine. Therefore, such an adsorbent having large pores can not only fundamentally remove the odor components contained in urine, but also fundamentally remove the odor derived from the protein components.

[0078] <Method for measuring pore diameter and volume>

[0079] The pore diameter and volume of various pores of the adsorbent can be measured in accordance with JIS Z 8831-2 (Pore diameter distribution and pore characteristics of powders (solids) - Part 2: Measurement method of medium pores and large pores based on gas adsorption) and JIS Z 8831-3 (Pore diameter distribution and pore characteristics of powders (solids) - Part 3: Measurement method of small pores based on gas adsorption). In addition, the adsorbent gas used for gas adsorption is selected as follows according to the pore diameter of the pore to be measured. That is, argon (measuring range 0.4nm to 100nm) is used when measuring pores with a pore diameter of 1.5nm to 2.0nm and pores with a pore diameter larger than this pore diameter, and carbon dioxide gas (measuring range 0.3nm to 1.5nm) is used when measuring micropores with a pore diameter of 0.3nm to 0.8nm. In addition, the present measurement method can be implemented using a commercially available fully automatic gas adsorption measurement device.

[0080] As described above, the adsorbent is not particularly limited in terms of appearance color, pores, and micropores, but is preferably composed of a plurality of porous particles. If the adsorbent is composed of a plurality of particles, it is easy to ensure a specific surface area of ​​a certain value or more and is easy to handle.

[0081] (Particle size)

[0082] When the adsorbent is composed of such a plurality of particles, it is more preferable that the adsorbent is composed of a plurality of particles having a particle size of 500 μm or less. If the adsorbent is composed of a plurality of particles having a particle size of 500 μm or less, the surface area of ​​the adsorbent that can be contacted by urine is larger, and the odor and color of urine can be adsorbed at a more excellent adsorption rate.

[0083] The particle size of the adsorbent is more preferably 200 μm or less, further preferably 100 μm or less, and particularly preferably 50 μm or less. The lower limit of the particle size of the adsorbent is not particularly limited, but is, for example, 0.1 μm or more, preferably 0.5 μm or more, from the perspective of ease of handling.

[0084] <Method for measuring particle size>

[0085] The particle size of the adsorbent can be measured using a laser diffraction / scattering particle size distribution measuring apparatus (for example, LA-920 manufactured by Horiba, Ltd.) under the following predetermined conditions, for example.

[0086] Measuring chamber: Flow cell

[0087] Particle diameter basis: volume

[0088] Dispersion medium: 90 mass% ethanol aqueous solution

[0089] Transmittance: 70% to 90%

[0090] Sample concentration: 0.1%

[0091] (Constitutional Materials)

[0092] The material constituting the adsorbent is not particularly limited as long as it has pores with a pore size of 1.5 nm to 2.0 nm at a volume of 0.006 mL / g or more and micropores with a pore size of 0.3 nm to 0.8 nm at a volume of 0.050 mL / g or more, and any porous substance can be used. Examples of such porous substances include activated carbon, silica gel, activated alumina, activated clay, acid clay, synthetic zeolite, porous synthetic polymers, and the like.

[0093] The activated carbon that can be used as the adsorbent is not particularly limited, but examples thereof include chemically activated activated carbon, steam activated activated carbon, etc. In addition, examples of chemically activated activated carbon include zinc chloride activated activated carbon, phosphoric acid activated activated carbon, etc.

[0094] The synthetic polymer that can be used as the adsorbent is not particularly limited, and examples thereof include synthetic polymers such as 2,6-diphenyl-p-phenylene ether polymers and divinylbenzene-styrene copolymers.

[0095] Among the porous substances mentioned above, the adsorbent preferably includes at least one porous substance selected from the group consisting of activated carbon, silica gel, activated alumina, activated clay, synthetic zeolite, and synthetic polymers. These porous substances have the advantages that they can stably exert adsorption effects and the pore sizes of the pores and micropores mentioned above can be easily controlled. Therefore, an absorbent article containing such an adsorbent can more reliably adsorb the odor and color of urine. In addition, from the perspective of versatility and ease of controlling the pore size of the pores, the porous substance is more preferably activated carbon.

[0096] In addition, the method for producing a porous material having pores with a pore size of 1.5 nm to 2.0 nm in a volume of 0.006 mL / g or more and micropores with a pore size of 0.3 nm to 0.8 nm in a volume of 0.050 mL / g or more is not particularly limited. For example, activated carbon having such pores and micropores can be obtained by appropriately selecting various manufacturing conditions such as the type of raw materials, carbonization temperature, and activation treatment conditions in the manufacturing method of activated carbon to control the pore size and volume of the pores, and the above-mentioned manufacturing method of activated carbon includes: a carbonization step in which a raw material such as a raw material derived from a plant is carbonized at a temperature of 800°C to 1400°C; a step of treating the carbonized activated carbon precursor with an acid (such as a fluorine compound such as hydrogen fluoride, hydrofluoric acid, etc.) or an alkali (such as sodium hydroxide, etc.); and an activation treatment step in which activation is performed by heat treatment using a gas such as oxygen or water vapor as an activator or chemical treatment using a chemical agent such as zinc chloride, phosphoric acid, and sulfuric acid as an activator.

[0097] In addition, the raw materials derived from plants that can be used as raw materials for activated carbon are not particularly limited, and examples thereof include rice, wheat, barley, barnyard grass, millet, straw, rice husk, coconut shell, wakame stem, conifer, vascular plant, pteridophyte, bryophyte, algae, seaweed, etc. These raw materials derived from plants can be used alone or in combination of two or more.

[0098] The structure of the porous material is not particularly limited except for having the above-mentioned fine pores and micropores. The porous material may have a particulate structure such as a powdery, granular, or granular structure, or may have a fibrous structure.

[0099] In addition, there is no particular limitation on the means for setting the appearance color of the adsorbent to a color having an L* value of 10 or more in the L*a*b* color system. For example, the L* value of the adsorbent can be adjusted to 10 or more by covering the surface of a porous substance such as activated carbon with a white inorganic substance, or the L* value of the adsorbent can be adjusted to 10 or more by forming the adsorbent using only a porous substance having a white color. In addition, examples of porous substances having a white color include synthetic zeolite and acid clay.

[0100] In this embodiment, it is preferred that, in the adsorbent, the porous substance is covered with at least one white inorganic substance selected from titanium oxide, calcium carbonate, zinc oxide, barium sulfate, magnesium oxide, kaolin and talc. Since these white inorganic substances have excellent concealing power, if the adsorbent is composed of the porous substance and the white inorganic substance covering the porous substance, it is more difficult to visually identify the pigment components of urine adsorbed and retained in the pores of the porous substance from the outside. In addition, the absorbent article containing such an adsorbent has the advantage of being able to further give the user a positive impression of cleanliness.

[0101] The above-mentioned white inorganic substance is more preferably a plurality of particles. If the adsorbent is composed of the above-mentioned porous substance and a plurality of white inorganic substance particles covering the porous substance, the odor components and pigment components of urine can be adsorbed and retained in the pores and micropores of the porous substance through the gaps between the particles of the white inorganic substance. That is, the adsorbent can make the pigment components adsorbed and retained in the pores of the porous substance less visible from the outside without causing any hindrance to the adsorption of the odor components and pigment components of urine. Therefore, an absorbent article containing such an adsorbent can more reliably suppress the odor of urine while further making the color of urine less conspicuous.

[0102] Here, the means for covering the surface of the porous substance with the white inorganic substance is not particularly limited. For example, the white inorganic substance may be attached to the surface of the porous substance by any bonding means such as an adhesive.

[0103] (Configuration location)

[0104] The adsorbent thus constructed can be arranged at any position of the absorbent article. For example, the adsorbent can be arranged at a position closer to the skin-opposite side than the back sheet. Specifically, the adsorbent can be arranged on the surface and / or inside of the surface sheet of the absorbent article, or on the surface and / or inside of the intermediate sheet arranged between the surface sheet and the absorbent body. Alternatively, the adsorbent can also be arranged on at least one of the surface and the inside of the absorbent body. Furthermore, in this case, the adsorbent can also be arranged on the surface and / or inside of at least one of the absorbent core and the core wrap sheet constituting the absorbent body.

[0105] In these configuration positions, it is also preferable that the adsorbent is configured at least one of the surface and the inside of the absorber. If the adsorbent is configured at such a position that is easily in contact with urine, the adsorbent can more reliably suppress the odor of urine and make the color of urine less noticeable.

[0106] (content)

[0107] The content of the adsorbent when the adsorbent is placed in the absorbent article is not particularly limited as long as it does not hinder the effect of the present invention, but preferably, the mass ratio of the adsorbent contained in the absorbent article is 0.1 mass % or more of the total mass of the absorbent article. If the adsorbent is contained in the absorbent article at such a mass ratio, the adsorbent can more reliably suppress the odor of urine and make the color of urine less noticeable.

[0108] In addition, it is more preferred that the mass ratio of the adsorbent contained in the absorbent article is 0.5 mass% or more of the total mass of the absorbent article, and it is particularly preferred that the adsorbent is contained in the absorbent article in a mass ratio of 1.0 mass% or more. The upper limit of the content of the adsorbent is not particularly limited, for example, the mass ratio of the adsorbent contained in the absorbent article can be 15 mass% or less of the total mass of the absorbent article. In addition, the mass ratio of the adsorbent can be measured as follows.

[0109] <Method for measuring the mass ratio of adsorbent>

[0110] (1) The constituent member in which the adsorbent is arranged (for example, the absorbent core of the absorbent body, the core wrap sheet, etc.) is removed from the absorbent article.

[0111] (2) The adsorbent is recovered from the removed component using physical means (e.g., vibration means, etc.) and / or chemical means (e.g., a solvent capable of dissolving the binder component, etc.). At this time, if foreign matter other than the adsorbent is mixed (e.g., fiber fragments, etc.), the foreign matter is removed using tweezers, etc., while the component is magnified and observed using a microscope, a simple magnifying glass, etc., and only the adsorbent is recovered.

[0112] (3) After measuring the mass (g) of the recovered adsorbent, the mass ratio (%) of the adsorbent can be calculated by dividing it by the total mass (g) of the absorbent article and multiplying the result by 100.

[0113] Hereinafter, various components of the absorbent article of the present invention will be described in detail using the incontinence pad 1 of the above embodiment. In addition, since the components of the absorbent article vary depending on the type and usage of the absorbent article, the various components described below are not necessarily indispensable components for the absorbent article.

[0114] (Surface Sheet)

[0115] In the above-mentioned incontinence pad 1, if Figure 1 As shown, the surface sheet 2 has a longitudinal shape when viewed from above, extending from the front side edge in the length direction L of the incontinence pad 1 to the rear side edge and from the vicinity of one side edge in the width direction W of the incontinence pad 1 to the vicinity of the other side edge. Figure 2As shown, the top sheet 2 is arranged on the skin-opposing side in the thickness direction T of the incontinence pad 1 and is composed of a liquid-permeable sheet member forming a contact surface that can abut against the wearer's skin. Examples of the liquid-permeable sheet member include hot air nonwoven fabrics.

[0116] The outer shape, dimensions, basis weight, etc. of the topsheet 2 are not particularly limited, and any shape, dimensions, basis weight, etc. may be adopted in accordance with desired liquid permeability, skin feel, softness, strength, etc.

[0117] In addition, the adsorbent having an L* value of 10 or more in the above-mentioned L*a*b* color system and having the above-mentioned specific pores and micropores can be arranged on the surface of the skin-opposing side and / or the non-skin-opposing side of the surface sheet 2, or can be arranged inside the surface sheet 2.

[0118] (Back sheet)

[0119] In the above-mentioned incontinence pad 1, the back sheet 3 has a longitudinal shape when viewed from above, extending from the front side edge in the length direction L of the incontinence pad 1 to the rear side edge and from one side edge in the width direction W of the incontinence pad 1 to the other side edge. Figure 2 As shown, the back sheet 3 is arranged at a position on the non-skin-opposite side in the thickness direction T of the incontinence pad 1, and is composed of a liquid-impermeable sheet member that prevents excretions such as urine that have passed through the absorbent body 4 from leaking to the outside of the incontinence pad 1. Examples of the liquid-impermeable sheet member include resin films, SMS nonwoven fabrics, and the like.

[0120] The outer shape, various dimensions, basis weight, etc. of the back sheet 3 are not particularly limited, and any shape, various dimensions, basis weight, etc. can be adopted according to the desired leakage prevention performance, air permeability, strength, etc.

[0121] Furthermore, an adsorbent having an L* value of 10 or more in the L*a*b* color system and having the above-mentioned specific fine pores and micropores may be disposed on the surface and / or inside of the skin-facing side of the back sheet 3 .

[0122] In the above-mentioned incontinence pad 1, an adhesive portion for bonding and fixing the incontinence pad 1 to the inner surface of the wearer's underwear may be arranged on the surface of the non-skin-opposite side of the back sheet 3. In addition, a liquid-impermeable leakproof sheet may be further provided between the back sheet 3 and the absorbent body 4. In addition, as the leakproof sheet, for example, a resin film composed of any thermoplastic resin such as polyethylene and polypropylene can be cited.

[0123] (Absorber)

[0124] In the above-mentioned incontinence pad 1, if Figure 1As shown, the absorbent body 4 has a longitudinally long outer shape when viewed from above, extending from the vicinity of one end edge in the length direction L of the incontinence pad 1 to the vicinity of the other end edge and from the vicinity of one end edge in the width direction W of the incontinence pad 1 to the vicinity of the other end edge. More specifically, the absorbent body 4 has a longitudinally long outer shape of a substantially gourd shape, with the central portion in the length direction L narrowing toward the inner side in the width direction W when viewed from above.

[0125] like Figure 2 As shown, the absorbent body 4 is arranged between the surface sheet 2 and the back sheet 3 in the thickness direction T of the incontinence pad 1, and is composed of a predetermined water-absorbent member that can absorb and retain excreta such as urine that has passed through the surface sheet 2. Specifically, the absorbent body 4 is composed of an absorbent core and a core wrap sheet that wraps the absorbent core, the absorbent core is composed of a water-absorbent material, and the core wrap sheet is composed of a hydrophilic fiber sheet.

[0126] The water-absorbent material constituting the absorbent core is not particularly limited as long as it can absorb and retain excreta such as urine, and any water-absorbent material known in the art can be used. Examples of such water-absorbent materials include superabsorbent polymers and hydrophilic fibers.

[0127] Examples of the super absorbent polymer include powders or granules formed of super absorbent polymers such as sodium acrylate copolymers, which are known in the art, and so-called SAP (Super Absorbent Polymer). Specific examples of the super absorbent polymer include polymers or copolymers of (meth)acrylic acid or (meth)acrylic acid alkali metal salts, preferably polymers or copolymers of sodium (meth)acrylate. In addition, in the present specification, (meth)acrylic acid refers to acrylic acid or methacrylic acid.

[0128] On the other hand, specific examples of the hydrophilic fibers include pulp fibers, cotton, rayon, cellulose fibers such as acetate, and the like.

[0129] Furthermore, the absorbent core may contain only one of the superabsorbent polymer and the hydrophilic fiber, or may contain both of the superabsorbent polymer and the hydrophilic fiber.

[0130] In the above-mentioned incontinence pad 1, the absorbent body 4 is composed of a core wrap sheet and an absorbent core containing a superabsorbent polymer, and the core wrap sheet is composed of a hydrophilic fiber sheet. In addition, an adsorbent having an L* value of 10 or more in the above-mentioned L*a*b* color system and having the above-mentioned specific pores and micropores is arranged inside the absorbent body 4. More specifically, the adsorbent is dispersedly arranged together with the superabsorbent polymer in the absorbent core. That is, the above-mentioned adsorbent is arranged in contact with the superabsorbent polymer. In this way, if the adsorbent is arranged at a position that is particularly easy to contact with urine, the adsorbent can be used to more reliably suppress the odor of urine and make the color of urine less conspicuous.

[0131] In addition, the adsorbent may be disposed on the surface of the absorbent core or on the inner surface of the core wrapping sheet that can contact the absorbent core. Furthermore, the adsorbent may be disposed on the outer surface of the core wrapping sheet (particularly the surface on the side opposite to the skin) or inside the core wrapping sheet.

[0132] The hydrophilic fiber sheet constituting the core sheet is not particularly limited as long as it is a fiber sheet through which urine and other excreta can pass, and a hydrophilic fiber sheet known in the art can be used. Examples of such a hydrophilic fiber sheet include a fiber sheet made mainly of conifer bleached kraft pulp having a unit weight of 10.0 g / m 2 ~20.0g / m 2 Around tissue paper, etc.

[0133] The outer shape, various dimensions, basis weight, etc. of the absorbent body 4 are not particularly limited, and any shape, various dimensions, basis weight, etc. can be adopted according to the desired water absorbency, softness, strength, etc.

[0134] (Side piece)

[0135] In the above-mentioned incontinence pad 1, if Figure 1 As shown, the pair of side panels 5, 5 have a pair of strip-shaped outer shapes extending along the length direction L at both ends in the width direction W of the incontinence pad 1 when viewed from above. Figure 2 As shown, a pair of side panels 5, 5 are arranged at positions on the skin-opposing side of the top sheet 2 in the thickness direction T of the incontinence pad 1. In addition, the outer ends of each of the pair of side panels 5, 5 in the width direction W are joined to the surface of the skin-opposing side of the back sheet 3 to form fixed ends, while the inner ends in the width direction W are not joined to any of the constituent members to form free ends.

[0136] By deforming the incontinence pad 1 in a curved manner along the length direction L when worn, the ends of the inner side of the pair of side panels 5, 5 on the width direction W as the free ends stand up, and a pair of leak-proof walls for preventing leakage of excreta such as urine can be formed. A pair of side panels 5, 5 can be formed by a hydrophilic or hydrophobic sheet member. As a hydrophilic or hydrophobic sheet member, for example, a hydrophilic or hydrophobic nonwoven fabric, a resin film, etc. can be listed.

[0137] The outer shape, various dimensions, basis weight, etc. of each of the pair of side sheets 5, 5 are not particularly limited, and any shape, various dimensions, basis weight, etc. according to the desired leakage prevention performance, etc. can be adopted.

[0138] In addition, the adsorbent having an L* value of 10 or more in the above-mentioned L*a*b* color system and having the above-mentioned specific pores and micropores can be arranged on the surface of the skin-opposing side and / or the non-skin-opposing side of a pair of side panels 5, 5, or can be arranged inside a pair of side panels 5, 5.

[0139] (use)

[0140] The present invention can be applied to various absorbent articles other than the incontinence pad of the above-described embodiment, for example, disposable diapers, sanitary napkins, panty liners, absorbent pads, and the like.

[0141] In addition, the application range of the present invention is not limited to absorbent articles, but can be applied to a wide range of uses that require urine treatment.

[0142] [Handling method]

[0143] Another embodiment of the present invention is a method for treating urine, comprising contacting urine with an adsorbent that absorbs the odor and color of urine. In this embodiment, the adsorbent has an L* value of 10 or more in the L*a*b* color system, has pores with a pore size of 1.5 nm to 2.0 nm in a volume of 0.006 mL / g or more, and has micropores with a pore size of 0.3 nm to 0.8 nm in a volume of 0.050 mL / g or more.

[0144] The urine treatment method of this embodiment includes: bringing urine into contact with an adsorbent that absorbs the odor and color of urine. As described above, the adsorbent can suppress the odor of urine and make the color of urine less noticeable without requiring other components. Therefore, the urine treatment method of this embodiment using such an adsorbent is less likely to be restricted in structure, can suppress the odor of urine and make the color of urine less noticeable, and can be applied to a wide range of uses that require urine treatment, such as absorbent articles.

[0145] In addition, the present invention is not limited to the above-mentioned embodiments, the following examples, etc., and can be appropriately combined, replaced, modified, etc. within the scope that does not depart from the purpose and spirit of the present invention.

[0146] Example

[0147] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

[0148] (Example 1)

[0149] After mixing 0.9 g of activated carbon (chemically activated activated carbon, manufactured by Osaka Gas Chemical Co., Ltd., product number: Strong White Eagle, raw material: conifer, particle size (median particle size): 52 μm) as a porous substance, 5.4 g of titanium oxide (particle size: 0.25 μm) as a white inorganic substance, and 1.31 g of a binder component (a mixture of 0.05 g of a 45% alkyl acrylate copolymer liquid, 0.01 g of carboxymethyl cellulose (CMC) and 1.25 g of water), the mixture was dried at 115° C. for two hours. Next, the dried mixture was pulverized using a pulverizer to obtain the adsorbent of Example 1 in which the surfaces of the activated carbon particles were covered with a plurality of titanium oxide particles.

[0150] (Example 2)

[0151] The adsorbent of Example 2 was obtained in the same manner as in Example 1, except that activated carbon having various pore volumes (steam-activated activated carbon, manufactured by Osaka Gas Chemical Co., Ltd., product number: White Eagle M, raw material: coniferous tree, particle size (median particle size): 45 μm) was used as the porous material.

[0152] (Example 3)

[0153] The adsorbent of Example 3 was obtained in the same manner as in Example 1 except that porous carbon raw materials (commercially available product (for business use), raw material: rice husk, particle size: 10 μm) with various pore volumes and raw materials were used as the porous substance.

[0154] (Example 4)

[0155] The adsorbent of Example 4 was obtained in the same manner as in Example 1 except that porous carbon raw materials (commercially available product (for business use), raw material: rice husk, particle size: 80 μm or less) with various pore volumes and raw materials were used as the porous substance.

[0156] (Example 5)

[0157] The adsorbent of Example 5 was obtained in the same manner as in Example 1 except that porous carbon raw materials (commercially available product (for business use), raw material: rice husk, particle size: 200 μm to 500 μm) with various pore volumes and raw materials were used as the porous substance.

[0158] (Comparative Example 1)

[0159] The adsorbent of Comparative Example 1 was obtained in the same manner as in Example 1, except that activated carbon having various pore volumes, raw materials, etc. (steam-activated activated carbon, manufactured by Osaka Gas Chemical Co., Ltd., product number: White Eagle WP, raw material: coconut shell, particle size (median particle size): 25 μm) was used as the porous material.

[0160] The volumes of pores with a pore size of 1.5 nm to 2.0 nm and micropores with a pore size of 0.3 nm to 0.8 nm of various porous materials used in the manufacture of Examples 1 to 5 and Comparative Example 1 were measured by a constant volume method using a fully automatic gas adsorption measurement device (AS-iQ-C) manufactured by Anton Paar. These measurement results are shown in Table 1 below.

[0161] In addition, the L* value of the L*a*b* color system of each adsorbent of Examples 1 to 5 and Comparative Example 1 was measured according to the above-mentioned <Method for measuring the L* value of the L*a*b* color system>, and the urine color and urine odor adsorption evaluation of each adsorbent was carried out according to the following <Urine color adsorption evaluation and urine odor adsorption evaluation method>. These measurement results and evaluation results are shown in the following Table 1.

[0162] <Urine color adsorption evaluation and urine odor evaluation method>

[0163] (1) 0.2 g of the adsorbent to be evaluated is placed in a sample bottle of a predetermined volume (eg, 50 mL), and 30 mL of actual adult urine is added to immerse the adsorbent in the urine.

[0164] (2) Put the lid of the sample bottle on the sealed state and leave it as it is for 15 hours.

[0165] (3) After 15 hours, the lid of the sample bottle was opened and the odor of the contents was smelled to perform a sensory evaluation of the intensity of the urine odor. In addition, in the sensory evaluation, the case where the urine odor was almost not recognizable was judged as "good" (indicated by the symbol "0"), and the case where the urine odor was clearly recognizable was judged as "unacceptable" (indicated by the symbol "×").

[0166] (4) The contents of step (3) above after 15 hours have passed were filtered to separate the adsorbent and the filtrate.

[0167] (5) A predetermined amount of the filtrate was taken and placed in a quartz cell. A standard white plate was placed on the back of the quartz cell. A colorimeter (CR-400 colorimeter manufactured by Konica Minolta, standard white plate [Y=93.0, x=0.3139, y=0.3202], ) to measure the b* value of the L*a*b* color system of the filtrate. The measured b* value is recorded as the "b* value after adsorption".

[0168] (6) As a blank, measure the b* value of the urine not impregnated with the adsorbent in the L*a*b* color system in the same manner as in the step (5) above. Record the measured b* value as the "b* value before adsorption".

[0169] (7) The b* value reduction rate (%) of the adsorbent to be evaluated is calculated based on the following formula and recorded as "dye adsorption rate (%)".

[0170] b* value reduction rate (%) = (b* value before adsorption - b* value after adsorption) / b* value before adsorption × 100

[0171] (8) Based on the obtained pigment adsorption rate, the degree of reduction in urine color was determined based on the following criteria.

[0172] ◎(Excellent): Pigment adsorption rate exceeds 80%

[0173] ○ (good): Pigment adsorption rate is 80% or less and more than 50%

[0174] × (unqualified): Pigment adsorption rate is less than 50%

[0175] [Table 1]

[0176] Table 1

[0177]

[0178] As shown in Table 1, it was found that each of the adsorbents of Examples 1 to 5 of the present invention can adsorb the color and odor of urine well. On the other hand, it was found that the adsorbent of Comparative Example 1 cannot sufficiently adsorb the color of urine.

[0179] Description of Reference Numerals

[0180] 1. Incontinence pad; 2. Surface sheet; 3. Back sheet; 4. Absorbent body; 5. Side sheets.

Claims

1. An absorbent article comprising an absorbent for absorbing the odor and color of urine, characterized in that: The L* value of the L*a*b* color system of the adsorbent is greater than 10, The adsorbent has pores with a pore diameter of 1.5 nm to 2.0 nm at a volume of 0.006 mL / g or more, and micropores with a pore diameter of 0.3 nm to 0.8 nm at a volume of 0.050 mL / g or more.

2. The absorbent article according to claim 1, wherein The adsorbent is composed of a plurality of particles having a particle size of 500 μm or less.

3. The absorbent article according to claim 1 or 2, characterized in that: The adsorbent includes at least one porous substance selected from the group consisting of activated carbon, silica gel, activated alumina, activated clay, synthetic zeolite, and synthetic polymers.

4. The absorbent article according to claim 3, wherein: In the adsorbent, the porous substance is covered with at least one white inorganic substance selected from titanium oxide, calcium carbonate, zinc oxide, barium sulfate, magnesium oxide, kaolin, and talc.

5. The absorbent article according to claim 4, characterized in that The white inorganic substance is a plurality of particles.

6. The absorbent article according to any one of claims 1 to 5, characterized in that: The absorbent article comprises an absorbent body, The adsorbent is disposed on at least one of a surface and an interior of the absorber.

7. The absorbent article according to claim 6, wherein: The absorbent body comprises an absorbent core comprising a superabsorbent polymer, The adsorbent is disposed in contact with the superabsorbent polymer.

8. The absorbent article according to any one of claims 1 to 7, wherein: The absorbent is contained in the absorbent article in an amount of 0.1% by mass or more based on the total mass of the absorbent article.

9. A method for treating urine, comprising bringing urine into contact with an adsorbent for absorbing the odor and color of urine, characterized in that: The L* value of the L*a*b* color system of the adsorbent is greater than 10, The adsorbent has pores with a pore diameter of 1.5 nm to 2.0 nm at a volume of 0.006 mL / g or more, and micropores with a pore diameter of 0.3 nm to 0.8 nm at a volume of 0.050 mL / g or more.

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