JP2009261536A - Sanitary napkin - Google Patents

Abstract

Provided is a sanitary napkin that includes a heating element, suppresses bleeding of absorbed body fluid such as menstrual blood, and is excellent in dry feeling and wearing feeling on a skin contact surface.
A sanitary napkin 1 according to the present invention includes a top sheet 2 constituting a skin contact surface, a back sheet 3 constituting a non-skin contact surface, and an absorbent body 4 disposed between both sheets 2 and 3. The heat generating layer 53 is arranged on the non-skin contact surface side of the absorber 4. In the longitudinal direction of the napkin 1, it has the excretion part opposing part B which opposes a wearer's excretion part at the time of the wear, and the front part A and the rear part C extended in the front and back, The width direction of this excretion part opposing part B The heat generating layer 53 is located only at the center. A waterproof and impermeable liquid-impermeable sheet 51 is disposed between the heat generating layer 53 and the absorber 4.
[Selection] Figure 2

Description

  The present invention relates to a sanitary napkin provided with a heating element that generates heat when exposed to air.

  A sanitary napkin is used for the treatment of menstrual blood and vaginal discharge. The sanitary napkin usually has a configuration in which an absorbent body for storing menstrual blood or the like is provided between a top sheet that forms the skin contact surface and a back sheet that forms the non-skin contact surface. Yes. 2. Description of the Related Art Conventionally, a sanitary napkin having such a configuration is known in which a heating element that generates heat when activated by oxygen, moisture, or the like in the air is provided.

  Regarding a sanitary napkin having a heating element, for example, Patent Document 1 describes a sanitary napkin in which a far-infrared emitting material (bincho charcoal powder) that emits far-infrared rays is provided between a back sheet and a top sheet. Has been. According to the sanitary napkin described in Patent Document 1, since the thermal effect is obtained by the action of the far-infrared radiation material, it is said that it helps to improve cooling and menstrual pain and also provides a deodorizing effect.

  Patent Document 2 describes a sanitary napkin in which a heating means for heating the absorbent body is disposed adjacent to the absorbent body. The sanitary napkin described in Patent Document 2 fully utilizes the absorption capacity of the absorbent body by reducing the viscosity of menstrual blood by increasing the heat generated by the heating means and increasing the fluidity of menstrual blood.

JP 2003-275237 A JP-T-2001-507602

  In the sanitary napkin described in Patent Document 1, menstrual blood once absorbed and held in the absorbent body may ooze out due to body pressure or the like. May cause fogging.

  In the sanitary napkin described in Patent Document 2, the heating means exists across the longitudinal direction of the napkin across the wearer's excretory part, and thus it tends to cause an uncomfortable feeling when worn. Further, when the absorbed body fluid such as menstrual blood comes into contact with the heating unit, the heat generation state of the heating unit is likely to change, and stable heat generation may be hindered. Moreover, there is a possibility that the body fluid with improved fluidity oozes out from the absorbent body, and the dry feeling of the surface sheet in contact with the skin is lowered. In addition, when the heating means generates heat when it comes into contact with moisture in the absorbed body fluid, the heating means does not generate heat until the napkin absorbs a certain amount of body fluid. It may not be obtained, and the effect of improving the absorption capacity due to heat generation may not be sufficiently obtained.

  Accordingly, an object of the present invention is to provide a sanitary napkin that includes a heating element, suppresses the exudation of absorbed body fluid such as menstrual blood, and is excellent in dry feeling and wearing feeling on the skin contact surface.

  The present invention comprises a top sheet that constitutes a skin contact surface, a back sheet that constitutes a non-skin contact surface, and an absorbent body disposed between both sheets, on the non-skin contact surface side of the absorbent body A vertically-long sanitary napkin in which a heat generating layer is arranged, and in the longitudinal direction of the napkin, an excretory part facing part facing the excretion part of the wearer when worn, and a front part and a rear part extending in front and back And the heat-generating layer is located only in the center in the width direction of the excretory part-facing part, and a waterproof and moisture-impermeable liquid-impermeable sheet is disposed between the heat-generating layer and the absorber. By providing a sanitary napkin that has been used, the above object is achieved.

  The present invention also includes a top sheet comprising a skin contact surface, a back sheet comprising a non-skin contact surface, a vertically long absorbent body comprising an absorbent body disposed between both sheets, and the absorbent body A sanitary napkin comprising a separate heating element, the heating element being disposed between a waterproof and moisture-impermeable liquid-impermeable sheet, a breathable sheet, and both sheets. And a heating layer that reacts with oxygen and generates heat, and is sealed before use of the napkin, and is provided on the non-skin contact surface of the absorbent main body or the outer surface of the liquid-impermeable sheet. A sanitary napkin used for fixing the heating element to the absorbent main body is provided through the fixing means, and fixing means for fixing the absorbent body to the absorbent main body is provided. It is a thing.

  The present invention is also an individual package of a sanitary napkin comprising the sanitary napkin and a non-breathable packaging material for individually packaging the sanitary napkin, wherein the napkin is sealed by the packaging material. The object is achieved by providing an individual package of a sanitary napkin in which the heating layer starts to generate heat by opening the material.

  According to the present invention, the action of the heating element promotes solidification of the body fluid such as menstrual blood absorbed by the absorber inside the absorber, so that exudation of the body fluid from the absorber is suppressed, It is excellent in the dry feeling of the skin contact surface, has little uncomfortable feeling when worn due to the heating element, and provides an excellent wearing feeling.

  Hereinafter, the sanitary napkin of the present invention will be described based on preferred embodiments with reference to the drawings. FIG. 1 shows a sanitary napkin 1 according to a first embodiment of the present invention together with a packaging material 10. FIG. 2 is a schematic diagram of a cross section taken along line II of FIG.

  As shown in FIGS. 1 and 2, the napkin 1 according to the first embodiment includes a liquid permeable top sheet 2 constituting a skin contact surface and a liquid impermeable back sheet 3 constituting a non-skin contact surface. And the liquid retaining absorbent 4 interposed between the sheets 2 and 3, and the heat generating layer 53 is disposed on the non-skin contact surface side of the absorbent 4. As shown in FIG. 3, the napkin 1 is hermetically sealed by a non-breathable packaging material 10 before use. The napkin 1 has a vertically long shape in plan view as shown in FIG.

  The napkin 1 has, in its longitudinal direction, an excretory part facing part B that opposes the excretion part of the wearer when worn, and a front part A and a rear part C that extend in front and back. The front part A is a part arranged near the wearer's abdomen when wearing the napkin, and the rear part C is a part arranged near the wearer's back when wearing the napkin. The excretory part opposing part B exists in the site | part biased to the front side a little rather than the longitudinal direction center part of the napkin 1. FIG. Usually, the length along the longitudinal direction of the napkin 1 of the excretory part facing part B is 30 to 40% with respect to the total length of the napkin 1 in the longitudinal direction.

  The top sheet 2 and the back sheet 3 extend outwardly from the left and right side edges and the front and rear side edges of the absorbent body 4, and the extended portions of both sheets 2 and 3 are formed by a known joining means such as heat treatment or adhesive. Are joined together. The absorber 4 has a vertically long rectangular shape with rounded corners in plan view. An adhesive portion (not shown) for fixing the napkin 1 to the underwear is disposed on the non-skin contact surface of the napkin 1 (the outer surface of the back sheet 3). The adhesive portion is formed so as to extend in the longitudinal direction of the napkin 1. The packaging material 10 is detachably fixed to the napkin 1 via the adhesive portion.

  In the present specification, the “skin contact surface” is a surface directed to the skin side of the wearer when wearing the napkin in the napkin or various members constituting the napkin, and the “non-skin contact surface” is the napkin or napkin. It is a surface which is turned to the underwear side (the side opposite to the wearer's skin side) when the napkin is worn in the various members constituting the. In addition, the “longitudinal direction” is a direction (longitudinal direction in FIG. 1) along the long side of the napkin or various members constituting the napkin, and the “width direction” is a direction orthogonal to the longitudinal direction (left and right in FIG. 1). Direction).

  The heat generating layer 53 is located only in the central part in the width direction of the excretory part facing part B. That is, the heat generating layer 53 exists only in the central part in the width direction of the napkin 1 in the excretory part facing part B, and does not exist in any part other than the central part in the width direction. As described above, since the heat generating layer 53 is located only in the central portion in the width direction of the excretory part facing part B that is disposed to face the excretion part of the wearer when the napkin is worn, the effect of the heat generating layer 53 (solid body fluid) It is possible to reduce the uncomfortable feeling and stuffiness caused by the heat generation layer 53 while fully exhibiting the promotion of the conversion and the suppression of the exudation of body fluid from the absorbent body), thereby providing an excellent wearing feeling It becomes. On the other hand, for example, as described in Patent Document 2, if the heating element (heating layer) is present across the excretory part-facing portion and straddles the front and back in the longitudinal direction, There is a possibility that incongruity and stuffiness are noticeable and a good wearing feeling cannot be obtained.

  From the viewpoint of improving the wearing feeling described above, the length L1 (see FIG. 1) of the heat generating layer 53 along the longitudinal direction of the napkin 1 is preferably 30 to 100 mm, more preferably 40 to 80 mm. The length W1 along the width direction of the napkin 1 at 53 (see FIG. 1; when the length W1 is not constant, the maximum width of the portion having the maximum width) is preferably 10 to 40 mm, more preferably 25-35 mm. Further, the length L1 of the heat generating layer 53 is preferably 10 to 30% with respect to the length in the longitudinal direction of the absorber 4, and the length W1 of the heat generating layer 53 is in the width direction of the absorber 4. It is preferably 10 to 40% with respect to the length (the maximum width of the portion having the maximum width when the length in the width direction of the absorber 4 is not constant). In addition, the length of the said longitudinal direction of the absorber 4 is 200-400 mm normally, and the length of the said width direction of the absorber 4 is 65-100 mm.

  As shown in FIG. 2, a waterproof and impermeable liquid-impermeable sheet 51 is disposed between the heat generating layer 53 and the absorber 4. The liquid impermeable sheet 51 is disposed adjacent to each of the heat generating layer 53 and the absorber 4. In the first embodiment, a breathable sheet 52 is disposed on the non-skin contact surface side of the heat generating layer 53 as shown in FIG. The breathable sheet 52 is disposed adjacent to each of the heat generating layer 53 and the back sheet 3. The heat generation layer 53 generates heat by reacting with oxygen, and is disposed between the liquid-impermeable sheet 51 and the air-permeable sheet 52.

  The liquid-impermeable sheet 51, the heat generating layer 53, and the air permeable sheet 52 constitute the heat generating element 5. All of the liquid-impermeable sheet 51, the heat generating layer 53, and the air-permeable sheet 52 have a quadrangular shape in plan view. Both sheets 51 and 52 extend outward from the left and right edges and both front and rear edges of the heat generating layer 53, and the extending portions of both sheets 51 and 52 are joined to each other by a known joining means such as heat treatment or adhesive. Has been. That is, the heat generating layer 53 is enclosed in a flat bag-shaped body composed of both sheets 51 and 52. The outer shape of the bag-like body matches the outer shape of the heating element 5. Between the liquid-impermeable sheet 51 and the heat generating layer 53 and between the heat generating layer 53 and the air permeable sheet 52 may be joined by known joining means such as an adhesive, respectively, and not joined. Also good. The dimension of the heating element 5 can be made substantially the same as that of the heating layer 53.

  By disposing a waterproof and moisture-impermeable liquid-impermeable sheet 51 between the non-skin contact surface side surface of the absorbent body 4 and the heat-generating layer 53, the liquid that has passed through the absorbent body 4 is heated. This prevents the heat generation layer 53 from maintaining a stable heat generation state, and the solidification of the body fluid by the heat generation layer 53 and the effect of suppressing the exudation of the body fluid from the absorbent body are reliably exhibited. Become so. As the liquid-impermeable sheet 51, a liquid-impermeable sheet-like material can be used, and examples thereof include a film made of a resin such as polypropylene and polyethylene; a spunbond nonwoven fabric having a meltblown layer, and the like. The liquid impervious sheet 51 may have air permeability or may not have air permeability.

The substantial thickness of the liquid-impermeable sheet 51 under no load is preferably 15 to 50 μm from the viewpoint of tearing and flexibility. The apparent thickness of the liquid-impermeable sheet 51 under no load is preferably 0.1 to 1.0 mm, particularly preferably 0.2 to 0.8 mm. Due to the apparent thickness of the liquid-impermeable sheet 51 being in such a range, when the heat generation layer 53 is not fixed to the liquid-impermeable sheet 51, the displacement of the heat generation layer 53 is more effective. In the case where the heat generation layer 53 is fixed to the liquid-impermeable sheet 51 using a joining means such as a hot-melt adhesive, the hardness when the napkin is worn due to the joining means is reduced. It can be reduced and the wearing feeling can be enhanced. Here, the substantial thickness is the thickness of the liquid-impervious sheet itself, and the apparent thickness is the thickness measured when the liquid-impervious sheet is provided with an uneven structure or the like including the uneven structure. is there. In addition, the basis weight of the liquid-impermeable sheet 51 is preferably 20 to 80 g / m ² , particularly 30 to 50 g / m ² , from the viewpoint of waterproofness and reduction in discomfort when wearing a napkin.

  Further, the air-permeable sheet 52 and the back-surface sheet 3 are formed by arranging the air-permeable sheet 52 between the heat-generating layer 53 and the surface of the back-surface sheet 3 on the skin contact surface side. Thus, the heat generation layer 53 comes into contact with the outside air, whereby the heat generation performance of the heat generation layer 53 is fully exhibited, and the moisture in the body fluid evaporated by the heat generation is on the non-skin contact surface side (back sheet) of the napkin 1 (3 side) permeates to the outside of the napkin and prevents stuffiness. As the breathable sheet 52, a sheet-like material having breathability can be used. For example, a porous film in which micropores are formed in a film made of a resin such as polyethylene and uneven processing is performed; a spunbond having a meltblown layer Non-woven fabric; air-through non-woven fabric subjected to water repellent treatment.

The apparent thickness of the breathable sheet 52 under no load is 0.2 to 2 mm, particularly 0.5 to 1 mm, which improves the breathability from the back sheet 3 at the lower part of the heat generating layer 53 and the entire heating element 5. From the viewpoint of improving air permeability. The upper and lower surfaces of the heat generating layer 53 are regions where the transpiration of the liquid absorbed by the absorber 4 is most likely to occur. Temporarily, the liquid is formed on the upper surface of the heat generating layer 53 (the surface on the skin contact surface side of the liquid impermeable sheet 51). Even if it is vaporized, the vapor is re-adsorbed by the pulp and the superabsorbent polymer constituting the absorber 4 at the front part A and the rear part C located at a position away from the heat generating layer 53. At that time, if there is a component in the absorbent body 4 that has a large change due to moisture absorption, such as pulp (for example, it is easy to be softened by moisture absorption), it becomes easy to give the absorbent body 4 a moist feeling by re-adsorption of vapor. However, since the heat generation layer 53 and the back sheet 3 are separated by the air permeable sheet 52, the vapor is easily guided to the air permeable sheet 52, so that the vapor is easily released to the outside of the napkin. Vapor re-adsorption at the surface is reduced, making it difficult to give the absorbent body 4 a moist feel. Moreover, when the unevenness | corrugation is formed in the back surface sheet 3, while being able to reduce the hardness at the time of napkin wearing resulting from the joining means of the heat generating layer 53 mentioned above, it is possible to increase the release of steam to the outside of the napkin. It has the advantage of being able to. Further, the basis weight of the breathable sheet 52 is preferably 20 to 80 g / m ² , particularly 30 to 50 g / m ² , from the viewpoint of maintaining the apparent thickness and stabilizing the release of vapor between the back sheet and the back sheet. .

  As described above, the heat generating layer 53 generates heat by reacting with oxygen. In the first embodiment, the heat generating layer 53 is made of a sheet-like material including an oxidizable metal and a fibrous material. As the oxidizable metal, an oxidizable metal conventionally used in this type of exothermic molded body can be used without particular limitation. As the form of the oxidizable metal, it is preferable to use a form having a powdery or fibrous form from the viewpoint of handleability and moldability.

  Examples of the oxidizable metal having a powder form include iron powder, aluminum powder, zinc powder, manganese powder, magnesium powder, and calcium powder. Among these, handling property, safety, and manufacturing cost are included. Iron powder is preferably used. The oxidizable metal has a particle size (hereinafter referred to as a particle size, the maximum length in the form of a powder, or a dynamic light scattering method, since the fixability to a fibrous material and the reaction control are good. The average particle diameter measured by a laser diffraction method, etc.) is preferably 0.1 to 300 μm, and the one having a particle diameter of 0.1 to 150 μm and containing 50% by weight or more is preferably used. Is more preferable.

  Examples of the oxidizable metal having a fibrous form include steel fibers, aluminum fibers, and magnesium fibers. Among these, steel fibers, aluminum fibers, and the like are preferably used from the viewpoints of handleability, safety, and manufacturing cost. As the oxidizable metal having a fibrous form, a fiber having a fiber length of 0.1 to 50 mm and a thickness of 1 to 1000 μm is used in terms of formability, mechanical strength of the obtained sheet, surface smoothness, and heat generation performance. It is preferable.

  The amount of the oxidizable metal in the heat generating layer 53 (sheet-like material) is preferably 10 to 95% by weight, more preferably 30 to 80% by weight. When the blending amount of the oxidizable metal is 10% by weight or more, the heat generation temperature of the heat generating body 5 obtained can be sufficiently increased to the extent that solidification of the body fluid is promoted, and the heat generating layer 53 is configured. Since the content of other components such as a fibrous material can be suppressed, the flexibility of the heat generating layer 53 can be maintained, which is preferable. On the other hand, when the blending amount of the oxidizable metal is 95% by weight or less, the heat generation layer 53 has sufficient air permeability, and as a result, the reaction sufficiently reaches the inside of the heat generation layer 53 to sufficiently increase the heat generation temperature. be able to. In addition, the heat generation time can be sufficient, and the oxidizable metal does not easily fall off. Here, the blending amount of the oxidizable metal in the heat generating layer 53 can be obtained by an ash test according to JIS P8128. For example, when the oxidizable metal is iron, magnetization occurs when an external magnetic field is applied. The property can be quantified by a vibration sample type magnetization measurement test or the like.

  Examples of the fibrous material blended in the heat generating layer 53 include natural fibers such as vegetable fibers (cotton, kabok, wood pulp, non-wood pulp, peanut protein fibers, corn protein fibers, soybean protein fibers, Mannan fiber, rubber fiber, hemp, Manila hemp, sisal hemp, New Zealand hemp, Rafu hemp, eggplant, rush, straw, etc.), animal fiber (wool, goat hair, mohair, cashmere, alkapa, Angola, camel, vicuña, silk, feathers , Down, feather, algin fiber, chitin fiber, casein fiber, etc.) and mineral fiber (asbestos, etc.). Examples of synthetic fibers include semi-synthetic fibers (acetate, triacetate, oxide acetate, promix, chloride). Rubber, hydrochloric acid rubber, etc.), metal fiber, carbon fiber, glass fiber and the like. Also, polyolefins such as high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene, etc., polyester, polyvinylidene chloride, starch, polyvinyl alcohol or polyvinyl acetate, single fibers such as copolymers or modified products thereof, or these A core-sheath composite fiber having a resin component in the sheath can be used. Among these, polyolefins and modified polyesters are preferably used because they have high adhesive strength between fibers, are easy to form a three-dimensional network structure by fusion of fibers, and have a melting point lower than the ignition point of pulp fibers. Synthetic fibers such as polyolefin having branches are also preferably used because of their good fixability with oxidizable metals and water retention agents. These fibers can be used alone or in combination of two or more. In addition, these fibers can be used in the form of collected and reused. Of these, wood pulp and cotton are preferably used from the viewpoints of fixability of the oxidizable metal, flexibility of the heat generating layer 53 (sheet-like material), oxygen permeability resulting from the presence of voids, production cost, and the like. It is done.

  The fibrous material preferably has a CSF (Canadian Standard Freeness) of 600 ml or less, and more preferably 450 ml or less. When the amount is 600 ml or less, the fixing ratio between the fibrous material and the oxidizable metal is sufficiently good, the predetermined blending amount can be sufficiently maintained, and the heat generation performance can be sufficiently exhibited. A sheet is obtained and the molded state is also good. In addition, the fixing between the fibrous material and the oxidizable metal is good, and the oxidizable metal is difficult to fall off, and the oxidizable metal and the fibrous material are entangled, so that sufficient bond strength can be provided by hydrogen bonding. . Further, the mechanical strength such as bending strength and tensile strength of the heat generating layer (sheet-like material) can be made sufficient, and the workability is also good.

  The fibrous material preferably has an average fiber length of 0.1 to 50 mm, more preferably 0.2 to 20 mm. When the average fiber length is within such a range, the mechanical strength such as bending strength and tensile strength of the obtained sheet-like material (heat generation layer) can be sufficiently secured. In addition, since the fiber layer is formed to have a desired density, the air permeability of the sheet-like material is sufficiently ensured, the oxygen supply of the heat generation layer obtained is good and the heat generation is excellent. Further, since the fibrous material can be uniformly dispersed in the sheet-like material, uniform mechanical strength can be obtained, and a sheet-like material having a uniform thickness can be obtained. In addition, since the fiber spacing is maintained in a desired range, the ability to hold components such as oxidizable metals by the fibers is maintained, and these components are difficult to drop off.

  The blending amount of the fibrous material in the heat generating layer 53 (sheet-like material) is preferably 2 to 50% by weight, more preferably 5 to 40% by weight. When the blending amount of the fibrous material is 2% by weight or more, the oxidizable metal can be sufficiently prevented from falling off, and the strength of the heat generating layer can be made sufficient. When the blending amount of the fibrous material is 50% by weight or less, it is possible to suppress the heat capacity with respect to the heat generation amount of the heat generating layer, and it is possible to increase the temperature sufficiently, and to be oxidizable in the heat generating layer to be obtained. Since the metal ratio can be secured to a certain level or more, the desired heat generation performance can be sufficiently obtained, which is preferable.

  In addition to the above-described oxidizable metal and fibrous material, the heat generating layer 53 (sheet-like material) includes a flocculant, a sizing agent, a colorant, a paper strength enhancer, a yield improver, a filler, as necessary. Additives usually used in paper making such as thickeners, pH control agents, bulking agents and the like can be added without particular limitation. The addition amount of the additive can be appropriately set according to the additive to be added.

  As the water retentive agent, a water retentive agent that has been conventionally used for exothermic molded bodies can be used without particular limitation. In addition to acting as a moisture retention agent, the water retention agent also has a function as an oxygen retention / supply agent for the oxidizable metal. Examples of the water retention agent include activated carbon (coconut husk charcoal, charcoal powder, calendar bituminous coal, peat, lignite), carbon black, acetylene black, graphite, zeolite, perlite, vermiculite, silica, cancrinite, fluorite and the like. Among these, activated carbon is preferably used because it has water retention ability, oxygen supply ability, and catalytic ability. As the water retention agent, it is preferable to use a powdery material having a particle size of 0.1 to 500 μm from the viewpoint that an effective contact state with an oxidizable metal can be formed. It is more preferable to use those containing at least wt%. As the water retention agent, a form other than the powder form as described above can be used. For example, a form of fiber form such as activated carbon fiber can also be used.

  The blending amount of the water retention agent in the heat generating layer 53 (sheet-like material) is preferably 0.5 to 60% by weight, more preferably 1 to 50% by weight. When the amount of the water retention agent is 0.5% by weight or more, the oxidizable metal sufficiently accumulates moisture in the heat generation layer to maintain the reaction to such an extent that the body fluid can be solidified by the oxidation reaction. it can. In addition, since air permeability is sufficiently ensured, a heat generation layer with high oxygen supply and high heat generation efficiency is obtained. When the amount of the water retention agent is 60% by weight or less, the heat capacity of the heat generation layer with respect to the heat generation amount obtained can be suppressed to a small value, so that the heat generation temperature rises and the body fluid can be solidified. . In addition, since occurrence of oxidizable metal is prevented from dropping and a decrease in the fibrous material constituting the heat generating layer 53, mechanical strength such as bending strength and tensile strength can be sufficiently obtained.

  The heat generating layer 53 (sheet-like material) preferably contains 50% by weight or more of components other than the fibrous material, more preferably 70% by weight or more, and more preferably 80% by weight or more. Further preferred. When the component other than the fibrous material is 50% by weight or more, the heat generation temperature can be sufficiently increased to the extent that the body fluid can be solidified. The more components other than the fibrous material, the better. However, the upper limit is preferably about 90% by weight from the viewpoint of obtaining the strength necessary to maintain the workability of the heat generating layer 53. Here, components other than the fibrous material are measured as follows.

Components other than the fibrous material in the heat generation layer 53 (sheet-like material) can be obtained from the following formula from the solid content weight in the raw material composition, the composition, and the dry weight of the heat generation layer 53.
Weight of raw material composition: Ms
Content of fibrous material in solid content of raw material composition: a (%)
Dry weight of heat generation layer (sheet-like material): Mh
Content of components other than fibrous material in heat generation layer (sheet-like material): b
b = (Mh / Ms) × (100−a)

  The heat generation layer 53 (sheet-like material) preferably has a moisture content (weight moisture content, hereinafter the same) of 10 to 80%, more preferably 20 to 60%. If the water content is 10% or more, sufficient water can be secured for maintaining the oxidation reaction. Moreover, it is excellent in that uniform heat generation performance can be sufficiently obtained. When the water content is 80% or less, the heat capacity with respect to the heat generation amount of the heat generating layer 53 can be suppressed, and the heat generation temperature can be sufficiently increased, and the air permeability of the heat generating layer 53 is also sufficient. Excellent performance, sufficient shape retention and mechanical strength.

  The heat generating layer 53 (sheet-like material) is prepared by preparing a raw material composition (slurry) containing the above-mentioned raw materials (oxidizable metals, fibrous materials, water retention agents, etc.) and water, and making paper by a known wet papermaking method. Is obtained. The heat generating layer 53 may have a single layer structure composed of one sheet-like material, or may have a multilayer structure in which a plurality of sheet-like materials are laminated and integrated. In the case of a multilayer structure, the composition may be the same or different in each layer.

  As the heat generating layer according to the present invention, it is possible to use a heat generating layer that is not in the form of a sheet such as the sheet-like material described above (for example, a non-flat bag-shaped heat generating layer in which a heat generating material is enclosed). Such a heat generating layer that is not in the form of a sheet is not sufficient in terms of control of heat generation and thickness. In order to suppress the occurrence of discomfort when wearing the napkin, it is effective to use a sheet-like material having a size of about 10 to 20 mm as the heat generating layer. In addition, the magnitude | size of such a heat generating layer measures the area | region where the heat-generating raw material in the heat generating layer is arranged.

In the first embodiment, the structure in which the heating element 5 is separated from the skin contact surface (surface sheet 2) of the napkin 1 by the absorber 4 makes it difficult to feel the hardness of the heating element 5 when worn. In addition to this, the thickness of the heat generation layer 53 under no load is 0.1 to 1.5 mm, particularly 0.2 to 1.0 mm, thereby including the hardness due to the heat generating element 5. It becomes possible to further reduce the uncomfortable feeling during various wearing. Further, the basis weight of the heat generating layer 53 is 10 to 1000 g / m ² , particularly 50 to 600 g / m ² , from the point of eliminating the flexibility of the heat generating element 5 and the uncomfortable feeling at the time of wearing due to the heat generating element 5. preferable.

  As the heat generating layer 53, a heat generating sheet described in Japanese Patent Application Laid-Open No. 2005-87719 related to the previous application of the present applicant can also be used.

The heating element 5 including the liquid-impermeable sheet 51, the air-permeable sheet 52, and the heat generation layer 53 (sheet-like material) described above has a thickness under no load of 1 to 5 mm, particularly 2 to 3 mm. This is preferable from the viewpoint of maintaining a stable exothermic state and eliminating the uncomfortable feeling when worn. In addition, the basis weight of the heating element 5 is preferably 10 to 1000 g / m ² , particularly 50 to 100 g / m ² , from the viewpoint of flexibility of the heating element and a decrease in uncomfortable feeling due to the heating element.

  The heating element 5 preferably has an exothermic temperature of 35 to 45 ° C, and more preferably 40 to 45 ° C. It is particularly preferable that the heat generation attainment temperature is higher than the body temperature of the napkin wearer. When the heat generation temperature is 35 to 45 ° C., the transpiration of water in the body fluid absorbed in the absorber 4 gradually proceeds, so that solidification of the body fluid occurs inside the absorber 4. Since solidification on the top sheet 2 is unlikely to occur, the dry feeling of the skin contact surface is improved. Moreover, if it is such a temperature range, it will be hard to produce stuffiness at the time of napkin wearing. If the exothermic temperature is too low, the transpiration of water does not proceed and it becomes difficult to solidify the body fluid. Conversely, if the temperature is too high, the transpiration of moisture proceeds rapidly, and solidification of the body fluid occurs on the top sheet 2. Therefore, the dry feeling of the skin contact surface may be reduced. The temperature at which heat is generated is measured as follows.

<Measurement method of heat generation temperature>
After cutting out a 50 mm × 50 mm test piece, a moisture permeable sheet having a moisture permeability of 5000 g / (m ² · 24 h) and a moisture impermeable sheet are attached to both sides in a bag shape and packaged on the test piece. A tester capable of supplying 5.0 liters / min of dry air in a sealed system under an environment of 4.2 liters and a relative humidity of 1% or less is prepared, and the moisture permeable sheet side is left as an upper surface inside the tester. Then, the temperature at the lower side of the test piece when the heat is generated is measured with a thermocouple, and this measured value is taken as the heat generation reached temperature of the test piece.

  The heat generation temperature can be controlled by the composition of the heat generation layer 53 and the air permeability of the napkin 1. In particular, suppressing the air permeability of the napkin 1 to be low is effective in that the heat generation temperature is set to a relatively low temperature of 35 to 45 ° C. and the temperature is maintained for a long time. Examples of the method for suppressing the air permeability of the napkin 1 to be low include the following methods 1) and 2).

  1) The breathable sheet disposed on the non-skin contact surface side with respect to the heat generating layer 53 is formed in a multilayer structure. In this case, there is a method of using a breathable sheet as the back sheet 3 in addition to a method in which the breathable sheet 52 itself, which is a constituent member of the heating element 5, has a multilayer structure. When the back sheet 3 is a breathable sheet, a breathable sheet having a multilayer structure of two or more layers including the breathable sheet 52 and the back sheet 3 is arranged on the non-skin contact surface side of the heat generating layer 53. Thus, the air permeability on the non-skin contact surface side of the napkin 1 is suppressed to a low level.

  2) An adhesive such as a hot melt adhesive is applied to the outer surface of the breathable sheet 52 and / or the breathable back sheet 3. It is preferable to apply the adhesive to at least the arrangement region of the heating element 5. When an adhesive such as a hot melt adhesive is applied to the outer surface of the back sheet 3, that is, the non-skin contact surface of the napkin 1, the adhesive application part functions as a breathable member and the napkin 1 is worn. Sometimes it can also function as an adhesive part that fixes the napkin 1 to the undergarment.

In the first embodiment, as shown in FIG. 1, a plurality of slits (cuts) 55 are formed on the surface of the heat generating layer 53 on the non-skin contact surface side (non-absorber side). More specifically, the plurality of slits 55 are all formed on the non-skin contact surface side of the heating element 5, and at least the lower layer portion of the heat generating layer 53 that contacts the air permeable sheet 52 from the air permeable sheet 52. It is formed over. The plurality of slits 55 are all linear slits extending in the longitudinal direction of the napkin 1, and are arranged in parallel at predetermined intervals in the width direction of the napkin 1. By forming a plurality of slits on the surface of the heat generating layer 53 (heat generating body 5) on the non-skin contact surface side, the flexibility of the heat generating layer 53 (heat generating body 5) is increased and the heat generating layer 53 (heat generating body 5) is formed. The uncomfortable feeling at the time of wearing the resulting napkin is reduced. From the viewpoint of improving the flexibility and wearing the napkin, the length of one slit 55 is preferably 20 to 100 mm, more preferably 30 to 60 mm. From the same viewpoint, the slit 55, 5~400mm / cm ^2, it is preferable that in particular 100 to 200 mm / cm ² formation. As shown in FIG. 1, the slit 55 may reach the outer edge of the heat generating layer 53 (heat generating body 5), or may not reach the outer edge. Further, the slit 55 may be a notch penetrating the heat generating layer 53 (heat generating element 5) in the thickness direction or may not penetrate. In the case of a slit that does not penetrate the heat generating layer 53 (heat generating body 5) in the thickness direction, the slit may be formed only on one surface of the heat generating layer 53 (heat generating body 5) or on both surfaces.

  It is preferable that the absorber 4 and the liquid-impermeable sheet 51 and the liquid-impermeable sheet 51 and the heat generation layer 53 are in close contact with each other from the viewpoint of maintaining a stable heat generation state. Examples of a method for bringing them into close contact include a method of applying various adhesives such as a hot melt pressure-sensitive adhesive between them.

  As the top sheet 2, the back sheet 3, and the absorbent body 4, various types conventionally used in the technical field can be used without particular limitation. As the surface sheet 2, for example, liquid permeable sheets such as various nonwoven fabrics and perforated films subjected to a hydrophilic treatment can be used. As the absorbent body 4, for example, a laminated layer obtained by depositing pulp fibers, or a nonwoven fabric made from pulp fibers can be used. The absorber 4 may contain superabsorbent hydrogel particles. Moreover, the absorber 4 may be entirely covered with a sheet material such as paper such as tissue paper or various nonwoven fabrics.

  As the back sheet 3, a liquid-impermeable or water-repellent material, for example, a film made of a thermoplastic resin, or a laminate of a nonwoven fabric can be used. A spunbond-meltblown-spunbond (SMS) nonwoven fabric or a spunbond-meltblown-meltblown-spunbond (SMMS) nonwoven fabric can also be used. As described above, the back sheet 3 preferably has moisture permeability. Examples of the back sheet having moisture permeability include a porous film obtained by extruding a resin composition containing a thermoplastic resin and fine particles incompatible with the thermoplastic resin into a film shape and uniaxially or biaxially stretching, and the above-described SMS nonwoven fabric. It is done.

  As shown in FIG. 3, the napkin 1 of the first embodiment is sealed with a non-breathable packaging material 10 before use to form an individual package 20. The packaging material 10 constitutes the outer surface of the individual package 20, and is a rectangular sheet that is larger than the napkin 1 and is long in the longitudinal direction of the napkin 1. The packaging material 10 is detachably adhered to the surface of the napkin 1 on the non-skin contact surface side (outer surface of the back sheet 3) via the adhesive portion (not shown), and is in an unfolded state as shown in FIG. 1 covers the entire surface of the napkin 1 on the non-skin contact surface side. In a state where the napkin 1 is sealed by the non-breathable packaging material 10, the heat generation layer 53 does not generate heat. That is, the heat generating layer 53 is sealed before the napkin 1 is used.

  The packaging material 10 includes a non-breathable material (having a property capable of blocking air), for example, a film made of a resin such as vinyl alcohol or nylon; a laminate of the film and an aluminum foil; silica on the film surface The film material etc. which vapor-deposited can be used. A peeling treatment may be performed on one or both sides of the packaging material 10. Examples of the peeling treatment include a method of applying a silicone resin-based material, heat drying and ultraviolet treatment, a spraying method and a method of forming a thin film with various coaters, etc. From the viewpoint of stabilizing the packaging material 10, it is preferable to use a separate release paper from the packaging material 10 without subjecting the packaging material 10 to a peeling treatment. That is, it is preferable to cover the adhesive part (not shown) with a release paper separate from the packaging material 10 and fix the packaging material 10 to the release paper with an adhesive or the like.

  The individual package 20 shown in FIG. 3 is obtained by folding the vertically long napkin 1 together with the packaging material 10 in the longitudinal direction and sealing a predetermined portion of the packaging material 10. For example, from the unfolded state shown in FIG. 1, the napkin 1 is folded in the longitudinal direction together with the packaging material 10 in the vicinity of the boundary between the excretory part facing part B and the rear part C, as shown in FIG. In the vicinity of the boundary between B and the front portion A, the napkin 1 is folded in the longitudinal direction together with the packaging material 10. At this time, the heating element 5 is preferably not bent. Both sides 10a, 10a of the packaging material 10 extending outward in the width direction from both side edges of the napkin 1 in a folded state in this way are sealed by a known joining method such as embossing and the like on the outer surface of the packaging structure 20 The longitudinal direction edge part 10b of the packaging material 10 located is sealed by this joining method. Thus, an individual package 20 in which the napkin 1 is sealed by the non-breathable packaging material 10 is obtained.

  In order to use the napkin 1 as the individual package 20, the sealing portions 10 a and 10 b are peeled off to open the packaging material 10 that seals the napkin 1, and is unfolded and packaged as shown in FIG. 1. After the material 10 is peeled off, the napkin 1 is fixed to the inner surface of the crotch part (crotch part) of the underwear via the adhesive part (not shown) according to a conventional method. By opening the packaging material 10 that seals the napkin 1, the napkin 1 is exposed to the outside air, and the non-skin contact surface side (breathable back sheet 3 side) of the napkin 1 is directed to the skin contact surface side. As a result, the air permeates, and the heating element 5 (heat generation layer 53) generates heat. That is, by opening the packaging material 10 constituting the individual package 20, the heat generating layer 53 starts to generate heat.

  According to the napkin 1 of the first embodiment, heat generated by the heating element 5 (heating layer 53) disposed on the non-skin contact surface side of the absorber 4 is absorbed by the absorber 4 inside the absorber 4. As a result, body fluid such as menstrual blood evaporates, thereby increasing the viscosity of the body fluid (decreasing fluidity) and solidifying the body fluid inside the absorbent body 4. As a result, even if pressure such as body pressure is applied to the absorbent body 4, the body fluid in the absorbent body 4 is solidified so that it does not ooze out from the absorbent body 4, so that leakage is prevented and the napkin 1 This leads to an improved dry feeling on the skin contact surface. Solidification of the body fluid is easier to proceed as it is closer to the heating element 5, that is, closer to the non-skin contact surface side of the absorber 4, and when using the breathable back sheet 3 as described above, Since moisture evaporates from the non-skin contact surface side of the napkin 1 through the back sheet 3, there is little possibility of causing stuffiness due to moisture evaporation. Moreover, since the heat generating layer 53 reacts with oxygen and generates heat, the heat generating layer 53 reacts with moisture in the body fluid as described in Patent Document 2 to generate heat, so that the napkin is worn. The time until the predetermined heat generation temperature is reached is short, and the above-described effects are rapidly manifested. In addition, since the waterproof and impermeable liquid-impermeable sheet 51 is disposed between the absorber 4 and the heat generating layer 53, the body fluid that has passed through the absorber 4 comes into contact with the heat generating layer 53. The heat generation state of the heat generation layer 53 does not change, and the above-described operational effects are stably expressed.

  Moreover, according to the napkin 1 of 1st Embodiment, since the heat generating body 5 (heat generating layer 53) is located only in the center part of the width direction of the excretion part opposing part B, the uncomfortable feeling at the time of wearing resulting from the heat generating body 5 There is little and a good feeling of wear is obtained. Furthermore, when the dimension of the heat generating layer 53 (the lengths L1 and W1) is set within the above-described range, the uncomfortable feeling is further reduced. In addition, by making the heat generating layer 53 a sheet-like material including the fibrous material as described above, the wearing feeling is further improved.

  Hereinafter, other embodiments of the present invention will be described. Regarding other embodiments described later, components that are different from the napkin of the first embodiment described above will be mainly described, and the same components will be denoted by the same reference numerals and description thereof will be omitted. The description about the napkin of 1st Embodiment is applied suitably to the component which is not demonstrated in particular.

  FIG. 5: is a cross-sectional view (cross-sectional view along the width direction of the excretory part opposing part of the absorptive main body mentioned later) which shows the use condition of the sanitary napkin of 2nd Embodiment of this invention. The napkin according to the second embodiment includes a top sheet 2 that constitutes a skin contact surface, a back sheet 3 that constitutes a non-skin contact surface, and an absorbent body 4 disposed between both sheets 2 and 3. The absorptive main body 1 ′ and the absorptive main body 1 ′ include a separate heating element 5.

  The napkin of 2nd Embodiment is that the heat generating body 5 is not contained in the absorptive main body 1 'which has a function as a sanitary napkin, and the heat generating body 5 is a different body from the absorptive main body 1'. And different from the napkin of the first embodiment. The heating element 5 of the second embodiment includes a waterproof and impermeable liquid-impermeable sheet 51, a breathable sheet 52, and an exothermic layer 53 that is interposed between the sheets 51 and 52 and generates heat by reacting with oxygen. And is sealed before use of the napkin. The heating element 5 of the second embodiment is configured in the same manner as the heating element 5 of the first embodiment. Moreover, the absorptive main body 1 'of 2nd Embodiment is comprised similarly to the napkin 1 of 1st Embodiment except the point which does not contain the heat generating body 5, and is the front part A and the excretion part opposition in a longitudinal direction. Part B and rear part C are provided.

  The heating element 5 of the second embodiment is sealed with a non-breathable packaging material (not shown) before use. In the state where the heating element 5 is sealed by the non-breathable packaging material, the heating layer 53 does not generate heat. As the packaging material for sealing the heating element 5, the same material as the packaging material 10 in the first embodiment can be used.

  Fixing means 7 for fixing the heating element 5 to the absorbent main body 1 ′ is provided on the non-skin contact surface of the absorbent main body 1 ′ (the outer surface of the back sheet 3) or the outer surface of the liquid-impermeable sheet 51 in the heating element 5. It is arranged. As the fixing means 7, a hot melt adhesive, an adhesive tape, or the like can be used. An adhesive portion (not shown) for fixing the heating element 5 to the underwear is disposed on the outer surface of the breathable sheet 52 in the heating element 5.

  As shown in FIG. 5, the napkin of the second embodiment is used by fixing the heating element 5 (liquid impermeable sheet 51) to the non-skin contact surface of the absorbent main body 1 ′ via the fixing means 7. The The fixing part of the heating element 5 is preferably the center in the width direction of the excretory part-facing part B of the absorbent main body 1 ′ from the viewpoint of improving the wearing feeling. That is, similar to the first embodiment described above, when the napkin is worn, the heating element 5 exists only in the central part in the width direction of the excretory part facing part B and does not exist in any part other than the central part in the width direction. Is preferred.

  In the absorbent main body 1 ′ and / or the heating element 5, the fixing point of the heating element 5 (preferably the non-skin contact surface in the center in the width direction of the excretory part facing part B of the absorbent main body 1 ′) is clearly shown. It is preferable from the viewpoint of maximizing the performance of the napkin and facilitating the fixing operation. For example, 1) the fixing location of the heat generating body 5 in the absorbent main body 1 ′ is recessed according to the outer shape of the heat generating body 2 and 2) the absorbent main body 1 ′ and / or the heat generating body 5 3), the fixing part of the heat generating body 5 'in the absorbent main body 1' is provided with fixing means such as a hot-melt pressure-sensitive adhesive and an adhesive tape. . These explicit methods can be combined as appropriate.

  The napkin of 2nd Embodiment can be used as follows, for example. First, the non-breathable packaging material (not shown) that seals the heating element 5 is opened to take out the heating element 5, and the removed heating element 5 is arranged on the outer surface of the breathable sheet 52. It fixes to the inner surface of the crotch part of underwear through an adhesion part (not shown). By opening the packaging material that seals the heating element 5, the heating element 5 is exposed to the outside air, whereby the heating element 5 (heating layer 53) starts to generate heat. Next, the absorbent main body 1 ′ is placed on the heating element 5 fixed to the crotch part of the underwear so that the predetermined portion of the non-skin contact surface overlaps the heating element 5, and the fixing means 7 is interposed therebetween. To fix both. The napkin of the second embodiment is used after the heating element 5 and the absorbent main body 1 ′ are sequentially fixed on the crotch part of the underwear as described above. The sanitary napkin of the second embodiment can achieve the same effects as those of the first embodiment.

As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said embodiment.
For example, the napkin 1 according to the first embodiment is folded as shown in FIG. 3 in the sealed state by the packaging material before use, but is not folded and sealed by the packaging material in the unfolded state as shown in FIG. May be.

FIG. 1: is the top view which looked at the expansion | deployment state of the sanitary napkin of 1st Embodiment of this invention from the skin contact surface side (surface sheet side). 2 is a cross-sectional view schematically showing a cross section taken along line II of the napkin shown in FIG. FIG. 3 is a perspective view of a state before use of the napkin shown in FIG. 1 (an individual package of sanitary napkins). FIG. 4 is a perspective view showing a process of folding the napkin together with the packaging material from the unfolded state shown in FIG. FIG. 5: is a figure which shows the use condition of the sanitary napkin of 2nd Embodiment of this invention, and the fixing | fixed part in the state which the heat generating body is being fixed to the absorptive main body (excretion part opposing part of an absorptive main body) FIG. 3 is a cross-sectional view (corresponding to FIG. 2) schematically showing a cross section (cross section along the width direction of the absorbent main body).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sanitary napkin 1 'Absorbent main body 3 Back surface sheet 4 Absorber 5 Heat generating body 7 Fixing means 10 Packaging material 20 Individual packaging 51 Liquid impervious sheet 52 Breathable sheet 53 Heat generating layer 55 Slit A Front part B Excretion part opposite Part C rear part

Claims (7)

It comprises a top sheet that constitutes the skin contact surface, a back sheet that constitutes the non-skin contact surface, and an absorber interposed between both sheets, and a heat generating layer is disposed on the non-skin contact surface side of the absorber. A vertically-long sanitary napkin,
In the longitudinal direction of the napkin, it has an excretory part facing part that faces the excretion part of the wearer when worn, and a front part and a rear part extending in front and back thereof, and only in the center part in the width direction of the excretion part facing part. The heating layer is located;
A sanitary napkin in which a waterproof and impermeable liquid-impermeable sheet is disposed between the heat generating layer and the absorber. A breathable sheet is disposed on the non-skin contact surface side of the heat generating layer,
The heat generating layer reacts with oxygen to generate heat, is disposed between the liquid-impermeable sheet and the breathable sheet, and is sealed before the napkin is used. The sanitary napkin according to 1. A vertically long absorbent main body comprising a top sheet that constitutes a skin contact surface, a back sheet that constitutes a non-skin contact surface, and an absorbent body disposed between both sheets; and a separate body from the absorbent main body A sanitary napkin comprising a heating element,
The heating element comprises a waterproof and moisture-impermeable liquid-impermeable sheet, a breathable sheet, and a heating layer interposed between both sheets and generating heat by reacting with oxygen, and before using the napkin Sealed,
Fixing means for fixing the heating element to the absorbent main body is disposed on the non-skin contact surface of the absorbent main body or the outer surface of the liquid-impermeable sheet, and the heating element is interposed through the fixing means. A sanitary napkin used by being fixed to the absorbent main body.   The sanitary napkin according to claim 3, wherein a fixing portion of the heating element is clearly shown on the absorbent main body and / or the heating element.   The sanitary napkin according to any one of claims 1 to 4, wherein a plurality of slits are formed on a surface of the heat generating layer on the non-skin contact surface side.   The sanitary napkin according to any one of claims 1 to 5, wherein the heat generating layer is made of a sheet-like material containing an oxidizable metal and a fibrous material. A sanitary napkin comprising the sanitary napkin according to any one of claims 1 to 6 and a non-breathable packaging material for individually packaging the sanitary napkin,
The napkin is sealed with the packaging material, and the package of the sanitary napkin starts to generate heat when the packaging material is opened.

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