JP6909556B2 - Sanitary napkin - Google Patents

Description

The present invention relates to a sanitary napkin that treats excrement containing blood such as menstrual blood and vaginal discharge in vitro.

Sanitary napkins are used to treat menstrual blood and vaginal discharge in women. A sanitary napkin usually has a configuration in which an absorber capable of absorbing and holding excrement such as menstrual blood is provided between a front surface sheet constituting the skin facing surface and a back surface sheet constituting the non-skin facing surface. As the absorber, those containing a water-absorbent polymer are often used. Since a water-absorbent polymer takes in water between the molecular chains that make up the polymer, it has high water absorption that absorbs water hundreds of times its own weight, and the hydrogel that swells by absorbing water is under pressure. It also has high water retention because it does not release water even if it is applied.

Regarding the technique for improving an absorbent article such as a sanitary napkin, for example, Patent Document 1 describes an absorbent article containing a stool denaturing agent that acts to denature the physical properties of excrement such as stool. As the stool denaturing agent, organic flocculants such as water-soluble polyamides, polyacrylics, polyamines, and polyvinylpyrrolidone are exemplified. According to the absorbent article described in Patent Document 1, the physical properties such as the viscosity of the excrement excreted by the wearer during wearing are changed by the action of the fecal denaturer, so that the negative influence of the excrement is minimized. It is expected that the absorption performance of excrement will be improved.

Patent Document 2 describes a physiological tampon that is inserted into the vagina and used to process menstrual blood in the body, and is made flexible as a tampon component for the purpose of preventing the tampon from falling out of the vagina during use. It is described that a rich water-soluble film is used, and the water-soluble film is prepared from a solution containing a film precursor such as polyacrylic acid or a cellulose derivative, a water-soluble plasticizer, and a pharmacologically active agent. Is described to be used. Further, Patent Document 2 describes that as the water-soluble plasticizer used for this water-soluble film, one having at least one functional group of a hydroxyl group, an amide group or an amino group is used, and as a specific example of the water-soluble plasticizer. , Propylene glycol, polyethylene glycol, glycerin and the like are described.

Japanese Unexamined Patent Publication No. 2010-194342 Japanese Unexamined Patent Publication No. 2001-341145

When a sanitary napkin containing a water-absorbent polymer is used for the treatment of menstrual blood, most of the surface of the water-absorbent polymer is covered with red blood cells contained in the menstrual blood, and as a result, the absorption performance of excrement by the water-absorbent polymer. There is a problem that It is considered that a technique for using a drug that changes the quality of excrement into a form that is easy to process, as described in Patent Document 1, is effective for such a problem related to menstrual blood, but is described in Patent Document 1. There is room for improvement in the technology, and even if the technology described in Patent Document 1 is adopted, such a problem cannot be solved. Further, when a water-soluble polymer that can be used as a stool modifier in Patent Document 1 is applied to a flexible sheet material made of a non-woven fabric or the like which is a constituent member of an absorbent article, the applied sheet material becomes hard. As a result, the fit may be reduced. Patent Document 2 does not suggest any problems such as improvement of absorption performance of menstrual blood and the like, particularly flexibility peculiar to sanitary napkins. Sanitary napkins that have excellent absorption performance of excrement including blood such as menstrual blood and vaginal discharge, and that are flexible and comfortable to wear have not yet been provided.

Therefore, the present invention relates to providing a sanitary napkin that has excellent absorption performance of excrement including blood such as menstrual blood and provides a comfortable wearing feeling.

As a result of various studies aimed at improving the absorption capacity of menstrual blood in sanitary napkins, the present inventors have conducted various studies to prevent the inconvenience that red blood cells contained in menstrual blood cover the surface of the water-absorbing polymer. A water-soluble cationic polymer having a high erythrocyte aggregation ability (weight average molecular weight of 500,000 or more) should be placed at a site where the menstrual blood excreted by the erythrocyte can come into contact with the menstrual blood before the water-absorbing polymer. However, it was found that it is effective in achieving such a purpose. However, it has been found that such a high molecular weight water-soluble cationic polymer is difficult to elute in menstrual blood, and it is difficult to obtain the expected effect even when the polymer is used alone. Therefore, as a result of further studies by the present inventors, by using a specific water-soluble plasticizer together with the water-soluble cationic polymer, the amount of the polymer eluted into menstrual blood is increased, and the desired effect of the polymer can be obtained. It was found that it can be expressed stably. That is, it was found that the water-soluble plasticizer functions as an elution accelerator. Further, when a water-soluble cationic polymer is applied to a flexible sheet material made of a non-woven fabric or the like, there is a concern that the sheet material will be cured and the wearing feeling of the sanitary napkin will be deteriorated. It was also found that the combined use of the agent) has the advantage of eliminating such concerns.

The present invention has been made based on the above findings, and includes a first layer containing a water-absorbent polymer and a second layer located closer to the wearer's skin than the first layer when worn. The second layer of the sanitary napkin contains an excrement treatment agent that acts on the blood contained in the wearer's excrement to alter the excrement, and the excrement treatment agent is water-soluble. Provided is a sanitary napkin containing a sex-cationic polymer and an elution accelerator having a hydrophilic group capable of promoting elution of the water-soluble cationic polymer into the excrement.

According to the present invention, there is provided a sanitary napkin that has excellent absorption performance of excrement including blood such as menstrual blood and can provide a comfortable wearing feeling.

FIG. 1 is a plan view schematically showing a skin-facing surface of an embodiment of the sanitary napkin of the present invention. FIG. 2 is a cross-sectional view schematically showing a cross section taken along line II of FIG.

The sanitary napkin of the present invention contains an excrement treatment agent that acts on the blood contained in the wearer's excrement to alter the excrement. When this excrement treatment agent comes into contact with menstrual blood, which is a typical excrement, the constituent components (water-soluble cationic polymer) of the excrement treatment agent are eluted into the menstrual blood, and the anionic property contained in the menstrual blood. The menstrual blood is altered by agglutinating the red blood cells of the blood cells to form a hemagglutination. Since the hemagglutination generated by the action of the excrement treatment agent is larger than that of erythrocytes, most of the surface of the water-absorbent polymer is blood cells even though the hemagglutination may adhere to a part of the surface of the water-absorbent polymer. The inconvenience of being covered with agglomerates is unlikely to occur, and therefore, the absorption performance inherent in the water-absorbent polymer is stably exhibited. Therefore, the sanitary napkin of the present invention containing such an excrement treatment agent is excellent in the absorption performance of excrement containing blood such as menstrual blood.

The excrement treatment agent according to the present invention contains at least a water-soluble cationic polymer. The water-soluble cationic polymer mainly functions as an agglutinating agent for erythrocytes contained in menstrual blood. The term "water-soluble" as used herein means that when 1 g of a cationic polymer is added to and mixed with 1 L of ion-exchanged water at a water temperature of 25 ° C., the entire amount of the cationic polymer dissolves in the ion-exchanged water within 24 hours. Means.

Examples of the water-soluble cationic polymer include polyethyleneimine, cationized cellulose, dimethylaminoethyl polymethacruate, polydimethylaminopropyl acrylamide and the like. Further, as another example of the water-soluble cationic polymer, "a water-soluble cationic polymer in which a side chain having a quaternary ammonium moiety is bonded to the main chain at one point" (hereinafter, "main chain-side chain singular". "Bound polymer") and "water-soluble cationic polymer in which the side chain having a quaternary ammonium moiety is bonded to the main chain at two or more points" (hereinafter, "main chain-side chain multiple bond polymer") Also called). In the present invention, one of these water-soluble cationic polymers can be used alone or in combination of two or more.

Examples of the main chain-side chain single-bonded polymer include poly (2-methacryloxyethyl dimethylamine quaternary salt), poly (2-methacryloxyethyl trimethylammonium salt), and poly (2-methacryloxyethyl dimethyl ethyl). Ammonium ethyl sulfate), poly (2-acrylic oxyethyl dimethylamine quaternary salt), poly (2-acrylic oxyethyl trimethylamine quaternary salt), poly (2-acrylic oxyethyl dimethyl ethyl ammonium ethyl sulfate), poly (2-acrylic oxyethyl dimethyl ethyl ammonium ethyl sulfate), poly ( 3-Dimethylaminopropylacrylamide quaternary salt), polyallylamine hydrochloride and the like. Examples of the main chain-side chain multiple-bonded polymer include polydialylamine hydrochloride, polydiallyldimethylammonium chloride, and polyamidine.

Among these water-soluble cationic polymers, a quaternary ammonium salt homopolymer and a quaternary ammonium salt copolymer are preferable, and in particular, a quaternary ammonium which is a kind of the main chain-side chain unilateral bond type polymer. Salt homopolymers and quaternary ammonium salt copolymers are preferable from the viewpoint of adsorptivity to erythrocytes.

A quaternary ammonium salt polymer, which is one of the preferred water-soluble cationic polymers, is a "cationic polymer having a quaternary ammonium moiety". The quaternary ammonium moiety can be generated by quaternary ammonium conversion of a tertiary amine with an alkylating agent. Alternatively, the tertiary amine can be dissolved in acid or water and neutralized to produce it. Alternatively, it can be produced by quaternary ammonium conversion by a nucleophilic reaction including a condensation reaction.
Examples of the alkylating agent include alkyl halides and dialkyl sulfates such as dimethyl sulfate and dimethyl sulfate. Of these alkylating agents, dialkyl sulfate is preferable because it does not cause the problem of corrosion that may occur when alkyl halide is used.
Examples of the acid include hydrochloric acid, sulfuric acid, nitrate, acetic acid, citric acid, phosphoric acid, fluorosulfonic acid, boric acid, chromic acid, lactic acid, oxalic acid, tartaric acid, gluconic acid, formic acid, ascorbic acid, hyaluronic acid and the like. Be done.
In particular, it is preferable to use a quaternary ammonium salt polymer in which the tertiary amine moiety is quaternary ammoniumized with an alkylating agent because the electric double layer of erythrocytes can be reliably neutralized.

Further, as a preferable example of the quaternary ammonium salt copolymer which is one of the other preferable water-soluble cationic polymers, a polymerizable monomer having a quaternary ammonium moiety and a cationic polymerizable monomer, Examples thereof include an anionic polymerizable monomer and a copolymer with a nonionic polymerizable monomer.
The example of the "polymerizable monomer having a quaternary ammonium moiety" is as described above as "a cationic polymer having a quaternary ammonium moiety".
Examples of the cationically polymerizable monomer include vinylpyridine as a cyclic compound having a cationic nitrogen atom under specific conditions, and a cationic nitrogen atom under specific conditions. Examples of the linear compound contained in the main chain include a condensed compound of dicyandiamide and diethylenetriamine.
Examples of the anionic polymerizable monomer include 2-acrylamide-2-methylpropanesulfonic acid, methacrylic acid, acrylic acid, styrenesulfonic acid, and salts of these compounds.
Examples of the nonionic polymerizable monomer include vinyl alcohol, acrylamide, dimethyl acrylamide, ethylene glycol, propylene glycol, ethylene glycol monomethacrylate, ethylene glycol monoacrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate, methyl methacrylate, and methyl acrylate. , Ethylene methacrylate, ethyl acrylate, propyl methacrylate, propyl acrylate, butyl methacrylate, butyl acrylate and the like.

Weight of the water-soluble cationic polymer such as a quaternary ammonium salt homopolymer and a quaternary ammonium salt copolymer from the viewpoint of enhancing the aggregation effect of erythrocytes and further improving the absorption capacity of the water-absorbent polymer for menstrual blood. The average molecular weight is preferably 500,000 or more, more preferably 1 million or more, and even more preferably 3 million or more. Such a high molecular weight water-soluble cationic polymer has a higher ability to agglutinate erythrocytes, which can be an absorption inhibitor of the water-absorbent polymer, than a low molecular weight polymer, but is eluted in menstrual blood due to its high molecular weight. Because it is difficult to do so, it is difficult for it to function as an agglutinant for red blood cells by itself. However, in the present invention, since a water-soluble plasticizer is used in combination with the water-soluble cationic polymer, even if a high-molecular-weight water-soluble cationic polymer is used, elution into excreta such as menstrual blood is substantially present. Therefore, an excellent hemagglutination effect is exhibited by the high molecular weight water-soluble cationic polymer, and as a result, the absorption capacity of excrement such as menstrual blood can be improved. The weight average molecular weight of the water-soluble cationic polymer can be measured by the following method.

<Measurement method of weight average molecular weight of polymer>
The molecular weight of the water-soluble cationic polymer can be measured using HLC-8320GPC manufactured by Tosoh Corporation. As a column, a guard column α manufactured by Tosoh Corporation and an analysis column α-M connected in series are used at a column temperature of 40 ° C., and an RI (refractive index) is used as a detector. The measurement sample is prepared by dissolving 1 mg of the water-soluble cationic polymer to be measured in 1 mL of the eluent. The measurement conditions are 1) when the water-soluble cationic polymer to be measured is a copolymer containing a water-soluble polymerizable monomer such as hydroxyethyl methacrylate, and 2) a water-soluble polymerizable simple polymer such as hydroxyethyl methacrylate. In the case of other than the copolymer containing the monomer, it differs from and to.

The specific measurement conditions in the case of 1) above are as follows. As the eluent, an eluent in which 150 mmol / L sodium sulfate and 1% by mass of acetic acid are dissolved in water is used. A mixture of pullulan having a molecular weight of 5900, pullulan having a molecular weight of 47300, pullulan having a molecular weight of 212,000, pullulan having a molecular weight of 788,000, and 2.5 mg each dissolved in 10 mL of the eluent is used as a molecular weight standard. The flow rate is 1.0 mL / min, and the injection volume of the measurement sample into the column is 100 μL.

The specific measurement conditions in the case of 2) above are as follows. As the eluent, an eluent in which 50 mmol / L lithium bromide and 1% by mass of acetic acid are dissolved in an ethanol aqueous solution having an ethanol: water = 3: 7 volume ratio is used. For 20 mL of the eluent, polyethylene glycol (PEG) having a molecular weight of 106, PEG having a molecular weight of 400, PEG having a molecular weight of 1470, PEG having a molecular weight of 6450, polyethylene oxide (PEO) having a molecular weight of 50,000, and PEO having a molecular weight of 235,000. A PEG-PEO mixture in which PEO having a molecular weight of 875,000 and 10 mg each is dissolved is used as a molecular weight standard. The flow rate is 0.6 mL / min, and the injection volume of the measurement sample into the column is 100 μL.

The content of the water-soluble cationic polymer in the excrement treatment agent according to the present invention (the total content thereof when a plurality of types of water-soluble cationic polymers are used in combination) is based on the total mass of the excrement treatment agent. It is preferably 20% by mass or more, more preferably 40% by mass or more, and preferably 80% by mass or less, further preferably 60% by mass or less, and more specifically, preferably 20% by mass or more and 80% by mass or less. More preferably, it is 40% by mass or more and 60% by mass or less. Even when the excrement treatment agent according to the present invention comprises only the water-soluble cationic polymer and the elution accelerator described later, that is, does not contain other components other than these two components, the water-soluble substance is used. The content of the cationic polymer is preferably in the above range. If the content of the water-soluble cationic polymer is too small, there is little significance in using it (prevention of absorption inhibition of the water-absorbent polymer due to blood in the excrement), and the content of the water-soluble cationic polymer is low. If the amount is too large, the water-soluble cationic polymer is excessively adsorbed on the blood cells and acts as a dispersant, and the aggregating action is diminished, so that a sufficient effect may not be exhibited.

The excrement treatment agent according to the present invention further comprises an elution accelerator having a hydrophilic group capable of promoting elution of the water-soluble cationic polymer into excrement such as menstrual blood in addition to the water-soluble cationic polymer. include. The elution accelerator is preferably one that is water-soluble and has an action of softening (plasticizing) a resin such as polyvinyl alcohol by addition, and a substance generally used as a water-soluble plasticizer can be used. The term "water-soluble" as used herein means that when 1 g of an elution accelerator (water-soluble plastic agent) is added to and mixed with 1 L of ion-exchanged water having a water temperature of 25 ° C., the total amount of the elution accelerator is within 24 hours. It means the property of being soluble in exchanged water, and is substantially the same as the "water-soluble" for the water-soluble cationic polymer described above.

Regarding the "water solubility" of the elution accelerator, the water solubility of the elution accelerator is preferably 0.05 g or more, more preferably 0.1 g or more, preferably 0.1 g or more, relative to 100 g of water at 25 ° C. It is 1 g or more. The elution accelerator preferably has a molecular weight exhibiting the above-mentioned water solubility.

Specific examples of the elution accelerator include polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, dibutylene glycol, glycerin, diglycerin, triglycerin, erythritol, and pentaerythritol. , Glycers such as polyethylene glycol; polyethers such as polypropylene glycol and the like can be mentioned, and one of these can be used alone or in combination of two or more.

As a preferable example of the elution accelerator (water-soluble plastic agent), one or more hydrophilic groups (water-soluble cationic polymer) selected from the group consisting of a hydroxyl group, an amide group and an amino group are promoted to be eluted into excreta. Those having a possible hydrophilic group) can be mentioned. Specific examples of preferable elution accelerators satisfying this condition include glycerin, polyethylene glycol, and ethylene glycol.

The content of the elution accelerator (when a plurality of types of elution accelerators are used in combination, the total content thereof) in the excrement treatment agent according to the present invention is preferably the total mass of the excrement treatment agent. 20% by mass or more, more preferably 40% by mass or more, and preferably 80% by mass or less, still more preferably 60% by mass or less, more specifically, preferably 20% by mass or more and 80% by mass or less, still more preferably. It is 40% by mass or more and 60% by mass or less. Even when the excrement treatment agent according to the present invention comprises only the water-soluble cationic polymer and the elution accelerator, that is, does not contain other components other than these two components, the elution accelerator. The content of is preferably in the above range. If the content of the elution accelerator is too small, there is little significance in using it (promotion of elution of the water-soluble cationic polymer, prevention of decrease in flexibility due to the water-soluble cationic polymer), and the elution accelerator. If the content of is too large, when it is applied to the constituent member (second layer) of the sanitary napkin and contained in the constituent member, a good content state in which a sufficient effect can be obtained can be obtained. It may not be maintained.

The excrement treatment agent according to the present invention can be prepared by mixing the above two components, that is, a water-soluble cationic polymer and an elution accelerator. The excrement treatment agent according to the present invention includes components other than the above-mentioned water-soluble cationic polymer and elution accelerator, for example, a viscosity modifier for improving coatability, as long as the gist of the present invention is not deviated. , A skin care agent, an antibacterial agent, a deodorant and the like may be contained.

The sanitary napkin of the present invention is composed of a first layer containing a water-absorbent polymer and a second layer located closer to the wearer's skin than the first layer when worn. Then, the excrement treatment agent is contained in the second layer. When the sanitary napkin is worn, the second layer is located closer to the wearer's skin than the first layer containing the water-absorbing polymer, so that the second layer is used for excrement such as menstrual blood excreted by the wearer. On the other hand, erythrocytes in the excrement, which usually come into contact before the first layer, may cause absorption inhibition of the water-absorbing polymer due to the inclusion of the excrement treatment agent in the second layer. Aggregates before reaching the water-absorbent polymer present in the first layer, and forms a blood cell agglomerate that is unlikely to cause absorption inhibition of the water-absorbent polymer. Therefore, the sanitary napkin of the present invention is excellent in the absorption performance of excrement containing blood such as menstrual blood.

In the sanitary napkin of the present invention, the first layer containing the water-absorbent polymer and the second layer containing the excrement treatment agent are adjacent to each other in the thickness direction without interposing another layer. Alternatively, one layer or two or more other layers (layers not containing the water-absorbing polymer and the excrement treatment agent) are interposed between the first layer and the second layer. Is also good.

The first layer containing the water-absorbent polymer may be composed of only the water-absorbent polymer, or may be composed of other components other than the water-absorbent polymer. A typical example of the first layer is a member, also called an absorbent core, usually contained in this type of absorbent article, specifically, for example, wood pulp, hydrophilized synthetic fibers, etc. Examples thereof include those composed of a fibrous material and a particulate water-absorbent polymer. In the absorbent core of such a configuration, the water-absorbent polymer is usually held in an aggregate of fiber materials via the adhesive force generated in the wet water-absorbent polymer or a binder such as a separately added adhesive or adhesive fiber. ing.

The water-absorbent polymer used in the present invention, that is, the water-absorbent polymer contained in the first layer, is preferably one that can absorb and retain a liquid having a weight of 20 times or more its own weight and can gel. Examples of such water-absorbent polymers include starches, crosslinked carboxylmethylated celluloses, polymers or copolymers of acrylic acid or alkali metal salts of acrylic acid, polyacrylic acid and salts thereof, and polyacrylate graft polymers. Can be mentioned. As the polyacrylate, a sodium salt can be preferably used. In addition, a copolymer such as maleic acid, itaconic acid, acrylamide, 2-acrylamide-2-methylpropanesulfonic acid, 2- (meth) acryloylethanesulfonic acid, 2-hydroxyethyl (meth) acrylate or styrenesulfonic acid is added to acrylic acid. A copolymer obtained by copolymerizing within a range that does not deteriorate the performance of the water-absorbent polymer can also be preferably used.

The shape of the water-absorbent polymer is not particularly limited, and any shape such as spherical, lumpy, grape-like, or fibrous can be used. The average particle size of the water-absorbent polymer is preferably 10 μm or more, more preferably 100 μm or more, and preferably 1000 μm or less, still more preferably 800 μm or less, more specifically, preferably 10 to 1000 μm, still more preferably 100 to 100 to 100. It is 800 μm.

The content (basis weight) of the water-absorbent polymer in the first layer per unit area is preferably 10 g / m ² or more, more preferably 50 g / m ² or more, and preferably 500 g / m ² or less, still more preferably. Is 400 g / m ² or less, more specifically, 10 g / m ² or more and 500 g / m ² or less, and more preferably 50 g / m ² or more and 400 g / m ² or less.

The second layer may be any one that can contain the excrement treatment agent and allow excrement such as menstrual blood to permeate, and is typically a liquid usually used in this type of absorbent article. It is a permeable sheet material, and specifically, paper, non-woven fabric, woven fabric, porous resin film and the like can be used. For example, when the first layer is the absorbent core, a liquid-permeable sheet material (so-called core wrap sheet) that covers the skin-facing surface of the absorbent core can be used as the second layer. .. The second layer may have a single-layer structure or a multi-layer structure in which a plurality of sheet materials are laminated. In the latter case, any layer may contain the excrement treatment agent. Further, the method of incorporating the excrement treatment agent in the second layer is not particularly limited, and the second layer is immersed in the excrement treatment agent by spray-coating the excrement treatment agent on the second layer. A known method such as, etc. can be used.

The content (basis weight) of the excrement treatment agent in the second layer per unit area is preferably 0.01 g / m ² or more, more preferably 0.5 g / m ² or more, and preferably 20 g / m / m. m ² or less, more preferably 10 g / m ² or less, more specifically 0.01 g / m ² or more and 20 g / m ² or less, still more preferably 0.5 g / m ² or more and 10 g / m ² or less. be. Even when the excrement treatment agent comprises only the water-soluble cationic polymer and the elution accelerator, that is, does not contain other components other than these two components, the excrement treatment agent has a tsubo. The amount is preferably in the above range.

1 and 2 show a napkin 1, which is an embodiment of the sanitary napkin of the present invention. The napkin 1 has a vertical direction X corresponding to the front-rear direction of the wearer and a horizontal direction Y orthogonal to the vertical direction X, and in a plan view as shown in FIG. 1, the maximum length of the vertical direction X is that of the horizontal direction Y. It has a vertically long shape that is relatively long, and more specifically, it has a substantially oblong shape in which the central portion in the vertical direction X is constricted inward.

The napkin 1 includes a liquid-permeable surface sheet 2 that forms the skin-facing surface of the napkin 1, a liquid-impermeable, liquid-impermeable, or water-repellent back sheet 3 that forms the non-skin-facing surface of the napkin 1. It is provided with a liquid-retaining absorber 4 interposed between the two sheets 2 and 3, and these are integrated by a known joining means such as an adhesive. The front surface sheet 2 and the back surface sheet 3 each extend from the peripheral edge of the absorber 4, and at the end of the extended portion, they are joined to each other by a known joining means such as an adhesive or a heat seal to form an end seal portion 5. Is forming. On the skin-facing surface of the napkin 1, a leak-proof groove 6 having an annular shape in a plan view is formed in which the surface sheet 2 and the absorber 4 are integrally recessed. A pair of side seats 7 and 7 are arranged on the left and right side portions of the napkin 1 on the skin-facing surface along the vertical direction X over substantially the entire length of the napkin 1 in the vertical direction X. In the present specification, the "skin facing surface" is a surface of the sanitary napkin or its constituent members that is directed toward the wearer's skin side when the sanitary napkin is worn, that is, a side that is relatively close to the wearer's skin. The "non-skin facing surface" is a surface of the sanitary napkin or its constituent members that is opposed to the skin side when the sanitary napkin is worn, that is, a surface that is directed to clothing such as shorts, in other words, relatively skin facing. The surface farther from the skin than the surface.

The absorber 4 includes a liquid-retaining absorbent core 41 and a core wrap sheet 42 that covers both the skin-facing surface and the non-skin-facing surface of the absorbent core 41. The absorbent core 41 is composed of a fiber material and a particulate water-absorbent polymer, and corresponds to the "first layer" according to the present invention described above. Further, in the core wrap sheet 42, at least the skin-side portion (the portion interposed between the surface sheet 2 and the absorbent core 41) that covers the skin-facing surface of the absorbent core 41 contains the excrement treatment agent. The skin-side portion of the core wrap sheet 42 corresponds to the "second layer" according to the present invention described above.

In the napkin 1 having such a configuration, when the menstrual blood excreted by the wearer permeates the surface sheet 2 and reaches the core wrap sheet 42 (second layer), the excrement contained in the core wrap sheet 42. The treatment agent elutes in menstrual blood, more specifically, the water-soluble cationic polymer contained in the excrement treatment agent acts as an action of the dissolution accelerator contained in the excrement treatment agent. Elutes in menstrual blood. As a result, erythrocytes in menstrual blood aggregate by the action of the water-soluble cationic polymer, and as a result, hemagglutination is formed in menstrual blood. The menstrual blood that reaches the core wrap sheet 42 permeates through it and reaches the absorbable core 41 (first layer), but during the menstrual blood that reaches the absorbable core 41, erythrocytes are usually substantially singular. What is contained in the menstrual blood is a hemagglutination larger than erythrocytes. Therefore, the inconvenience that most of the surface of the water-absorbent polymer in the absorbable core 41 is covered with red blood cells is unlikely to occur, and the absorption performance originally inherent in the water-absorbent polymer is sufficiently exhibited in the napkin 1. Further, although the core wrap sheet 42 contains the water-soluble cationic polymer, it does not lose its original flexibility due to the action of the elution accelerator, and therefore, the napkin 1 as a whole is flexible and comfortable. A comfortable fit can be obtained.

The sanitary napkin of the present invention is not limited to the illustrated form (napkin 1), and can be appropriately modified without departing from the spirit of the present invention. For example, in the napkin 1, the excrement treatment agent may be contained in the surface sheet 2 instead of the core wrap sheet 42. That is, the surface sheet 2 may be the "second layer" according to the present invention. Alternatively, both the core wrap sheet 42 and the surface sheet 2 may contain the excrement treatment agent.

In addition, a sanitary product such as a commercially available sanitary napkin has an excrement treatment agent according to the present invention, that is, an elution having a water-soluble cationic polymer and a hydrophilic group capable of promoting elution of the water-soluble cationic polymer into excrement. Whether or not the "composition containing the accelerator" is contained can be confirmed by the following method. First, the hot melt adhesive that adheres each member to the sanitary product to be analyzed is invalidated by using a heating device such as a dryer, and the product is decomposed into members such as a front sheet, an absorber, and a back sheet. Next, a multi-step solvent extraction method from a non-polar solvent to a polar solvent was performed on each of the decomposed members, the treatment agent used for each member was separated, and a solution containing a single composition was prepared. obtain. Then, the obtained solution is dried and solidified, and the weight is measured. At the same time, 1H-NMR (nuclear magnetic resonance method), IR (infrared spectroscopy), LC (liquid chromatography), GC (gas chromatography), MS ( Mass spectrometry), GPC (gel spectroscopy), fluorescent X-ray, etc. are combined to identify the structure of the treatment agent. Based on such identification results, among the treatment agents separated from the sanitary products, the water-soluble and cationic polymer is treated as the "water-soluble cationic polymer" according to the present invention, and the one having a hydrophilic group is according to the present invention. Treat as a "dissolution accelerator" (water-soluble plasticizer), treat other substances as other components, and calculate the blending amount of each.

〔Example〕
Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to such Examples.

(Preparation of excrement treatment agent)
The excrement treatment agents A to H having the compositions shown in Table 1 below were prepared. Details of the water-soluble cationic polymer and elution accelerator used in the preparation are as follows.
(1) Water-soluble cationic polymer polydialyldimethylammonium hydrochloride (weight average molecular weight 600,000) (quaternary ammonium salt homopolymer): Unisense FPA1000L manufactured by Senka Co., Ltd.
Polymethacryloxyethyl dimethylammonium diethylsulfate (weight average molecular weight 5.2 million) (quaternary ammonium salt homopolymer): Methacrylicoxyethyldimethylammonium ethylsulfate monomer is dissolved in ethanol as a solvent and is oil-soluble. It was prepared by adding 2,2'-Azobis (2-methylpropionamide) dihydrochloride (V-65B manufactured by Wako Pure Chemical Industries, Ltd.), which is an azo initiator, and heating and polymerizing.
Polydiallyl dimethylammonium hydrochloride (weight average molecular weight 150,000) (quaternary ammonium salt homopolymer): Merquat 100 Polymer manufactured by Lubrizol.
(2) Elution accelerator (water-soluble plasticizer)
・ Glycerin: Made by Wako Pure Chemical Industries, Ltd. (special grade reagent)
-Polyethylene glycol: manufactured by Wako Pure Chemical Industries, Ltd. (Wako first-class product)

[Evaluation test 1]
Using the prepared excrement treatment agent, a model sheet of "a second layer containing the excrement treatment agent in a sanitary napkin" was prepared. Specifically, as a model sheet of a core wrap sheet that covers an absorbent core in a sanitary napkin, a 5 cm square ^{tissue paper having a basis weight of 16 g / m 2} is prepared, and the mass of the tissue paper is increased with respect to one side of the tissue paper. A model sheet was prepared by spraying and drying an amount of the excrement treatment agent to be evaluated, which corresponds to 400% by mass. The amount of the excrement treatment agent adhered to the model sheet was 5.0 g / m ² . The volume swelling ratio of the water-absorbent polymer was evaluated for the prepared model sheet by the following method. The results are shown in Table 1 below. The larger the value of the volume swelling ratio, the higher the performance of preventing absorption inhibition of the water-absorbent polymer (red blood cell agglutination ability) by the excrement treatment agent, and the higher the evaluation.

<Evaluation method of volume swelling ratio of water-absorbent polymer>
First, two acrylic cylinders with an inner diameter of 35 mm, whose upper and lower ends are open, are arranged vertically with the axes of both cylinders aligned, and the model sheet to be evaluated is sandwiched between the upper and lower cylinders. In the upper cylinder, 3 g of blood whose viscosity has been adjusted to 8 mPa · s is repeatedly supplied 3 times at 3 minute intervals. The supplied blood permeates the model sheet and disappears from the upper cylinder. Blood that has permeated the model sheet is collected.
Next, one grain of a water-absorbent polymer having a diameter of about 400 μm is placed on a slide glass, and three drops of blood collected by the above operation are dropped onto the water-absorbent polymer by a pasteur pipette, and the water-absorbent polymer is dropped. The blood was absorbed and swollen. After dropping the blood, the water-absorbent polymer was sealed with a small screw lid to prevent evaporation of water. After 10 minutes, the lid was removed, and an excess amount of blood present in the water-absorbent polymer was absorbed and removed using an absorbent paper. Subsequently, the diameter of the water-absorbent polymer was measured by light microscopy. When the diameter of the water-absorbent polymer before swelling is R1 (μm) and the diameter after swelling is R2 (μm), the volume swelling ratio is defined by ^{(R2 / R1) 3.}

[Examples 1 and 2 and Comparative Examples 1 to 5]
A sanitary napkin having the same structure as the napkin 1 shown in FIGS. 1 and 2 was prepared according to a conventional method. An air-through non-woven fabric having a basis weight of 25 g / m ² was used as the front surface sheet, and a non-moisture permeable polyethylene film having a ^{basis weight of 37 g / m 2 was used as the back surface sheet.} As the absorbent core (first layer), a hot melt that uses a dryer to bond each member from a commercially available sanitary napkin (Kao Corporation 2015 "Laurier Slim Guard Firmly with wings for daytime 25 cm"). The adhesive was invalidated, disassembled and taken out. As the core wrap sheet (second layer) for covering the absorbent core, tissue paper having ^{a basis weight of 16 g / m 2 was used.} The core wrap sheet containing the excrement treatment agent was prepared by applying any one of the excrement treatment agents A to F to the entire core wrap sheet and drying it.

[Evaluation test 2]
The amount of liquid return (wetback amount) and flexibility of the sanitary napkins of Examples and Comparative Examples were evaluated by the following methods. Regarding the flexibility, a core wrap sheet (second layer) was taken out from the sanitary napkin to be evaluated, and the taken out core wrap sheet was evaluated by the following method. The results are shown in Table 2 below.

<Evaluation method of flexibility>
Daiei Kagaku Seiki Co., Ltd., using the core wrap sheet to be evaluated, in accordance with the handle ometer method described in "JIS L 1096 Fabric Test Method for Woven Fabrics and Knitted Fabrics" (8.20. Compressibility and Compressibility E Method). The measurement was performed using a handle ometer (HOM-3) manufactured by Mfg. Co., Ltd. The test piece had a quadrangular shape in a plan view of 50 mm × 50 mm, and the slit width was measured at 5 mm. The smaller the value of the pressure to be measured, the more flexible the test piece is. Indicates that it is difficult to reduce.

<Evaluation method of liquid return amount>
The sanitary napkin to be evaluated is spread out in a plane and placed horizontally so that the skin facing surface side (surface sheet side) faces upward, and is made of acrylic having a cylinder inner diameter of 22 mmφ and a cylinder height of 50 mm on the napkin. An acrylic liquid injection plate integrally molded so that the cylindrical part is located on the liquid injection opening of 10 mmφ, and the liquid injection hole is located in the center of the excretion part facing region on the skin facing surface (surface sheet side) of the napkin. Place them on top of each other so that they are positioned, and place an appropriate weight plate on them (including the injection plate itself) to adjust the ^{load to 5 g / m 2.} Weigh 3 g of horse defibrotic blood manufactured by Japan Biotest Research Institute Co., Ltd., whose viscosity has been adjusted to 8 mPa · s, in a 10 cc liquid injection beaker. After pouring this blood into the cylinder of the injection plate at once, leave it for 3 minutes, then pour 3 g again, and leave the pukkin as it is for 3 minutes. Immediately after that, 10 sheets of weighed absorbent paper (Advantech 5A, 55 mmφ) and a rectangular weight of 960 g were placed on the part of the napkin where blood was poured, and left to stand for 10 seconds. From the weight, the amount (g) of blood sucked by the absorbent paper is calculated. The measurement is performed three times, and the average value is used as the amount of liquid returned from the napkin. The smaller the value of the liquid return amount, the better the absorption performance of the napkin.

表１より、水溶性カチオン性ポリマーを有しない排泄物処理剤Ｈよりも、水溶性カチオン性ポリマーを有する排泄物処理剤Ａ〜Ｇの方が、吸水性ポリマーの体積膨潤倍率が優れていることがわかる。また、表２より、水溶性カチオン性ポリマーを有しない比較例４及び５よりも、水溶性カチオン性ポリマーを有する実施例１及び２並びに比較例１〜３の液戻り量は優れている。さらに、溶出促進剤を併せて有する実施例１及び２は液戻り量と柔軟性とを両立していることがわかる。

From Table 1, the volume swelling ratio of the water-absorbent polymer is superior to the excrement treatment agents A to G having the water-soluble cationic polymer than the excrement treatment agent H having no water-soluble cationic polymer. I understand. Further, from Table 2, the amount of liquid return of Examples 1 and 2 having the water-soluble cationic polymer and Comparative Examples 1 to 3 is superior to that of Comparative Examples 4 and 5 having no water-soluble cationic polymer. Further, it can be seen that Examples 1 and 2 also having an elution accelerator have both a liquid return amount and flexibility.

1 Sanitary napkin 2 Front sheet 3 Back sheet 4 Absorber 41 Absorbent core (first layer)
42 core wrap sheet (second layer)
5 End seal part 6 Leakage-proof groove 7 Side sheet X Vertical direction Y Horizontal direction

Claims (5)

A sanitary napkin including a first layer containing a water-absorbent polymer and a second layer located closer to the wearer's skin than the first layer when worn.
The second layer contains an excrement treatment agent that acts on the blood contained in the wearer's excrement to alter the excrement.
The excrement treatment agent is seen containing a water-soluble cationic polymer, and a dissolution promoter having a hydrophilic group capable of promoting the dissolution into the bodily waste of the water-soluble cationic polymer,
The water-soluble cationic polymer includes poly (2-methacryloxyethyldimethylamine quaternary salt), poly (2-methacryloxyethyltrimethylammonium salt), poly (2-methacryloxyethyldimethylethylammonium ethyl sulfate), and poly. (2-Acrylicoxyethyl dimethylamine quaternary salt), Poly (2-Acrylic oxyethyl trimethylamine quaternary salt), Poly (2-Acrylic oxyethyl dimethyl ethyl ammonium ethyl sulfate), Poly (3-Dimethylaminopropyl acrylamide 4) Classified salt), polyallylamine hydrochloride, polydialylamine hydrochloride, polydialyldimethylammonium chloride or polyamidine, one or more selected from the group consisting of a quaternary ammonium salt homopolymer and a quaternary ammonium salt copolymer. A sanitary napkin having a weight average molecular weight of 500,000 or more. The water-soluble cationic polymer is the quaternary ammonium salt copolymer, and is a polymerizable monomer having a quaternary ammonium moiety, a cationic polymerizable monomer, an anionic polymerizable monomer, or an anionic polymerizable monomer. The sanitary napkin according to claim 1 , which is a copolymer with a nonionic polymerizable monomer. The content of the excrement treatment agent in the second layer per unit area is 0.5 g / m. ² More than 10g / m ² The sanitary napkin according to claim 1 or 2 below. The content of the water-soluble cationic polymer in the excrement treatment agent is 20% by mass or more and 80% by mass or less with respect to the total mass of the excrement treatment agent.
The content of the elution accelerator in the excrement treatment agent is 20% by mass or more and 80% by mass or less with respect to the total mass of the excrement treatment agent according to any one of claims 1 to 3. Sanitary napkin. The sanitary napkin according to any one of claims 1 to 4, wherein the hydrophilic group contained in the elution accelerator is at least one selected from the group consisting of a hydroxyl group, an amide group and an amino group.

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