JP4420809B2 - Heating tool - Google Patents

Description

  The present invention relates to a heating tool that uses heat generated by oxidation of an oxidizable metal, and more particularly to a heating tool that is prevented from being swollen after the end of heat generation.

The present applicant has previously proposed a water vapor generator utilizing the oxidation heat generated by an oxidizable metal (see Patent Document 1). This water vapor generating device is suitably used as a facial device for effectively cleaning facial skin by opening pores with water vapor, or as a steam mask that moistens the mucous membrane of the throat and nose by sucking water vapor. This water vapor generating device is a sheet-like heat generating structure in which an oxidizable metal is contained in a heating element containing portion formed by laminating a breathable sheet having air permeability and a non-breathable sheet having no air permeability. Has a body. The moisture permeability of the moisture permeable sheet in the heating element housing portion is set to a high value of 7000 to 15000 g / m ² · 24 h in view of the above-mentioned use, and thereby a large amount of water vapor of 30 mg or more in 15 minutes per 1 cm ^2. Is to be released. Also, the generation of water vapor is completed in a relatively short time of several minutes to one hour. The planar heating element during the generation of water vapor is slightly swollen due to an increase in internal pressure due to the generation of water vapor, but returns to its original flat shape after the generation of water vapor. Therefore, it is not necessary to pay special attention to the swelling of the planar heating element.

  The thing of patent document 2 is known as a heat retention tool aiming at preventing the burst by the internal pressure increase. This heat retaining device is formed by enclosing an inner bag in which a gel-like heat storage material is liquid-tightly enclosed in an outer bag. The sealing portion of the outer bag is provided with a non-adhesive portion to form a ventilation portion that communicates the inside and the outside of the outer bag. Thereby, when the inner bag is ruptured, only the expansion gas is discharged to the outside through the ventilation portion while holding the heat storage material inside the outer bag. However, since this heat retaining device does not generate water vapor, it does not relate to an increase in internal pressure due to the generation of water vapor.

International Publication WO03 / 103444 Pamphlet JP 2002-113032 A

  It is an object of the present invention to provide a heating tool that can prevent swelling that occurs after the end of heat generation in a heating tool that uses heat generated by oxidation of an oxidizable metal.

INDUSTRIAL APPLICABILITY The present invention can generate heat by contact with air in a container provided with a breathable portion having a moisture permeability (JIS Z0208, 40 ° C., 90% RH) of 200 to 2000 g / m ² · 24 hr at least in part. Contains heat-generating materials containing oxidizable metals,
The heat-generating material has a water content of 10 to 70% by weight after completion of heat generation,
The housing body is the area that 30～600Cm ² breathable sites in該収condition, by providing a heating tool 2000～126000Myuemu ² vents for communicating the inside and outside of該収condition is provided The object has been achieved.

  According to the present invention, the swelling of the heating tool after the generation of water vapor is effectively prevented, and the appearance impression is prevented from being lowered. Further, it is possible to prevent the user from feeling uneasy.

  The present invention will be described below based on preferred embodiments with reference to the drawings. FIG. 1 shows a perspective view of an embodiment of the heating tool of the present invention. 2 is a cross-sectional view taken along line II-II in FIG. A heating tool 1 shown in FIG. 1 has a flat rectangular shape, and includes a heating sheet 2 as a sheet-shaped heating material and a housing 3 that houses the heating sheet 2. As will be described later, the heat generating sheet 2 is composed of a fiber sheet and is formed slightly smaller than the container 3. The container 3 has a flat bag shape, and a plurality of sheet materials are bonded together to form a hollow bag shape. The container 3 is a breathable part at least part of which has moisture permeability.

  The heat generating sheet 2 can generate heat by contact with air. For this purpose, the heating sheet 2 contains an oxidizable metal, a reaction accelerator, a fibrous material, an electrolyte, and water. When the heat generating sheet 2 comes into contact with air, an oxidation reaction of an oxidizable metal contained in the sheet 2 occurs and heat is generated. The water contained in the heat generating sheet 2 is heated by this heat to become water vapor having a predetermined temperature, and is discharged to the outside through the container 3. The water vapor is released from the breathable portion of the container 3 to the outside.

  The heating tool 1 of the present embodiment is used to give heat accompanied by the generation of water vapor to an object such as a human body (specific uses will be described later). The heating tool 1 of the present embodiment is characterized by a long duration of water vapor generation. It has been found that the heating tool 1 having such characteristics is applied to the lumbar region and shoulders of the human body to heat these parts, thereby promoting blood circulation throughout the body and increasing the peripheral temperature. It was also found that the temperature increase continued for several tens of minutes after the heating was stopped. In contrast to this, the above-mentioned effect is not observed even when the same part is heated under the same temperature condition with a general disposable body warmer with a small amount of water vapor. When the present inventors examined this reason, it turned out that the heat | fever accompanying generation | occurrence | production of water vapor | steam has high heat conductivity, and can raise the temperature of the deep part of a human body. It is presumed that the temperature in the deep part of the human body increases, thereby stimulating the thermal center, thereby expanding blood vessels and increasing blood flow, and increasing peripheral temperature. Therefore, the heating tool 1 is effective not only for improving the temperature and improving blood circulation of a part of the human body to which the heating tool 1 is applied, but also for improving blood circulation of the entire body, increasing the peripheral temperature of fingertips, and improving the cooling property.

In order to obtain a heating tool having the above-mentioned characteristics, that is, a heating tool having a long duration of water vapor generation, the amount of oxidizable metal used, the moisture content in the heating sheet 2 before heating, the breathable part of the container 3 It is important to control values such as moisture permeability. In general disposable warmers, since the composition of the heat generating material and the structure of the container do not actively generate water vapor, the amount of water contained in the heat generating material is small. On the other hand, since the heating tool of the present invention actively generates water vapor, it has a heat generating material having a composition containing moisture as a raw material for water vapor in addition to water necessary for heat generation. In the heating device 1 in which values such as moisture content and moisture permeability are appropriately controlled, when this is applied to human skin, the release of water vapor with a skin surface temperature of 38 ° C. or higher is preferably 2 hours or longer, Preferably it is maintained for 5 hours or more. Further, the cumulative amount of water vapor released 90 minutes after the heating sheet 2 comes into contact with air is preferably 1.4 to 7.0 mg / cm ² , more preferably 2.2 to 7.0 mg / cm ^2. (This is hereinafter referred to as a water vapor release characteristic). The skin surface temperature refers to the temperature of the skin surface measured by a contact thermometer, for example, a thermocouple.

The cumulative amount of water vapor released in the water vapor release characteristic is measured by the following method.
In a closed system with a volume of 54,000 cm ³ (length 30 cm × width 50 cm × depth 36 cm) at a temperature of 20 ° C. and a humidity of 40% RH, the heating tool 1 is left standing so that water vapor can evaporate therein to generate heat. And the humidity of the air in the said closed system is measured with a hygrometer, and the amount of water vapor generated after the start of heat generation is obtained. The integrated value after 90 minutes is taken as the integrated release amount.

  When steam is generated using the heating tool having the above-described water vapor release characteristics and a predetermined time elapses, the temperature of the heating tool gradually decreases, and the amount of water vapor generated decreases. When the time further elapses, the heat generation ends and the generation of water vapor stops. When the heating tool 1 is left as it is, a phenomenon in which the heating tool 1 gradually expands is observed. This phenomenon is a phenomenon that has not been observed in the steam generator described in Patent Document 1 described in the section of the prior art. When the present inventors examined the cause of this phenomenon, this phenomenon does not occur in a steam generator of a type that releases a large amount of water vapor in a short time, but it does not occur for a long time as in the present invention. Was found to be a phenomenon peculiar to the type of sustained release type. The cause of this phenomenon is the water content remaining in the heat generating sheet 2 after the end of the heat generation and the accommodation among the factors listed above as the main factors for obtaining the heat generating tool having a long duration of water vapor generation. It has been found that it is closely related to moisture permeability at the breathable part of the body 3.

  Specifically, the greater the water content remaining in the heat generating sheet 2 after the end of heat generation, the more noticeably the swelling of the heating tool 1 becomes. Specifically, when the water content of the heat generating sheet 2 after the heat generation is 10 to 70% by weight, particularly 20 to 70% by weight, the swell of the heating tool 1 becomes remarkable (under an environment of 20 ° C. and 40% RH). . When the moisture content of the heat generating sheet 2 after heat generation is less than 10% by weight, since the amount of water vapor staying in the container 3 is small, the container 3 does not swell or even if it swells, there is no problem. Level and bulges wither in a short time. The moisture content of the heat generating sheet 2 can be obtained from the remaining heating amount of the heat generating sheet 2. Specifically, the difference between the weight of the heat generating sheet 2 after the end of heat generation and the remaining amount of heating is divided by the weight of the heat generating sheet 2 after the end of heat generation and multiplied by 100 to obtain the moisture content (%) of the heat generating sheet 2 It becomes. The heating conditions are 105 ° C. and 40 minutes. The heating atmosphere is nitrogen gas. The weight of the sample is 3 to 10 g. The term “after heat generation” means the time when the surface temperature of the heat generating sheet 2 becomes room temperature or 30 ° C. or less.

Further, the moisture permeability (JIS Z0208, 40 ° C., 90% RH) of the breathable portion in the container 3 is 200 to 2000 g / m ² · 24 hr, particularly 300 to 2000 g / m ² · 24 hr, especially 500 to 1200 g / m ^2. -The swelling of the heating tool 1 is observed when it is 24 hours. When the moisture permeability is 2000 g / m ² · 24 hr or less, the water vapor staying in the container 3 is not sufficiently released to the outside of the container 3, so that swelling occurs, but the desired temperature can be maintained sufficiently. it can. When the moisture permeability is 200 g / m ² · 24 hr or more, the heating tool 1 swells, but a desired water vapor release characteristic can be obtained.

  As will be described later, the moisture permeable sheet 3a, which is a breathable part in the container 3 of the present embodiment, is provided with a vent hole 6, but in the case of measuring the moisture permeability of the moisture permeable sheet 3a. A portion where the vent hole 6 is not provided is selected as a measurement target.

The inventors presume that the principle that the heating tool 1 swells is as follows. As shown in FIG. 3A, at least one surface of the container is a moisture permeable sheet. Through this moisture permeable sheet, the gas moves inside and outside due to the partial pressure difference of the gas, and the pressure difference is relaxed. The moisture permeability is as described above, and since the relaxation time has a finite time in this range, it is considered that the following phenomenon occurs. In the heating tool 1 in which the generation of water vapor is completed and the temperature is lowered to around room temperature, a large amount of water that has not been volatilized as water vapor remains in the heat generating sheet 2. Therefore, the water vapor partial pressure Pa _H2O in the container 3 is substantially equal to the saturated water vapor pressure. On the other hand, the water vapor partial pressure Pb _H2O outside the container 3 is usually lower than the saturated water vapor pressure. Apart from the water vapor partial pressure, the air partial pressures Pa _AIR and Pb _AIR in the container 3 are substantially the same with respect to the air partial pressure. That is, Pa _H2O > Pb _H2O and Pa _AIR ≈Pb _AIR . Therefore, when the pressure inside and outside the container 3 is compared, the pressure inside the container 3 is higher by the amount of Pa _H2O -Pb _H2O . As a result, the action of lowering the water vapor partial pressure Pa _H2O in the container 3 works and the container 3 swells. In particular, in an environment where the water vapor partial pressure Pa _H2O outside the container 3 is low, for example, in an environment where the air is dry, such as in winter, a large difference occurs in the water vapor partial pressure inside and outside the container 3. Swelling becomes prominent.

FIG. 3B shows a state where the container 3 is swollen by this action. In this state, the water vapor partial pressure Pa _H2O in the container 3 is reduced by the amount of expansion of the container 3, and substantially coincides with the water vapor partial pressure Pb _H2O outside the container 3. On the other hand, with respect to the air partial pressure, the air partial pressure Pa _AIR in the container 3 is reduced by the amount of expansion of the container 3. There is no change in the air partial pressure Pb _AIR outside the container 3. That is, Pa _H2O ≈Pb _H2O and Pa _AIR <Pb _AIR . Accordingly, the action of balancing the air partial pressure inside and outside the container 3 works, and air is taken into the container 3 from the outside of the container 3.

FIG. 3C shows a state in which air is taken into the housing 3 from the outside of the housing 3. In this state, Pa _H2O ≈Pb _H2O and Pa _AIR ≈Pb _AIR . This condition is temporary and does not last for a long time. The reason is that a large amount of water still remains in the heat generating sheet 2 in the container 3. Specifically, water vapor is generated from the remaining water, and the water vapor partial pressure Pa _H2O in the container 3 rises and becomes higher than the water vapor partial pressure Pb _H2O outside the container 3 (FIG. 3 (d)). As a result, the state returns to the state of Pa _H2O > Pb _H2O and Pa _AIR ≈Pb _AIR , that is, the state shown in FIG. This state change occurs repeatedly, and the heating tool 1 swells to the limit.

  While the heat generating sheet 2 generates heat and water vapor is generated, the water vapor partial pressure in the container 3 rises, but oxygen in the container 3 is consumed by oxidation and the partial pressure is substantially zero. Therefore, the total pressure inside the container 3 is lower than the total pressure outside the container 3, that is, atmospheric pressure (that is, negative pressure), and the heating element 3 does not swell.

  As is clear from the above explanation, the swelling of the heating tool 1 after the generation of water vapor is caused by the magnitude of the partial pressure of water vapor in the container 3, so that the swelling itself has a health hazard to the human body. Absent. However, since the heating tool 1 swells after use, there is a risk that the user may feel useless anxiety that gas or the like that causes health hazards has been generated. In addition, there is a problem that the appearance impression is lowered due to the expansion of the heating tool 1, and there are environmental problems such as bulkiness at the time of disposal. Therefore, in the heating tool 1 of the present embodiment, the following measures are taken to prevent the heating tool 1 from expanding after use.

In the heating tool 1 of the present embodiment, a vent hole 6 that allows the inside and outside of the housing 3 to communicate with each other is provided in the housing 3. As a result of the study by the present inventors, it has been found that even if the size of the vent hole 6 is very small, it has a sufficient effect for preventing swelling. Specifically, the total area of the vent hole 1 is sufficient as long as 2000 .mu.m ² (about 50μmφ circle equivalent diameter) ~126000μm ² (about 400μmφ circle equivalent diameter) of about preferably 8000μm ² (circle equivalent diameter 100 μmφ) to 50000 μm ² (about 250 μmφ in equivalent circle diameter), more preferably 9500 μm ² (about 110 μmφ in equivalent circle diameter) to 32000 μm ² (about 200 μmφ in equivalent circle diameter). If the area of the vent hole 6 is 2000 μm ² or more and 126000 μmφ or less, the inflow of air through the vent hole 6 does not become significant, and the heat generation characteristics and water vapor release characteristics of the heat generating sheet 2 can be controlled. Also, abnormal heat generation can be prevented. Furthermore, powder leakage through the vent hole 6 can also be prevented.

  In the present embodiment, the number of the vent holes 6 is one, but two or more vent holes may be formed as long as the total area is within the above range. However, when a large number of ventilation holes are provided, the area of each ventilation hole is reduced, and there may be no substantial difference from the case where the ventilation holes 6 are not provided. From this viewpoint, when a plurality of vent holes are formed, the equivalent circle diameter of each vent hole is preferably 50 to 400 μmΦ, particularly 100 to 250 μmΦ, particularly 110 to 200 μmΦ. When a plurality of vent holes are formed, the size of each vent hole may be the same or different. When the size of each vent hole is different, it is most preferable that the equivalent circle diameter of all the vent holes is within the above range, but the present invention is not limited to this. In a particularly preferred embodiment, it is advantageous to provide one vent hole 6 having the aforementioned area and equivalent circle diameter.

  The area of the vent hole 1 is measured using, for example, a microscope (VH-8000) manufactured by Keyence. The equivalent circle diameter is calculated from the measured area. When a plurality of vent holes 1 are provided, the equivalent circle diameter is obtained from the sum of the areas.

The area of the vent 6 is also related to the area of the breathable portion having moisture permeability in the container 3. Area breathable sites 30～600Cm ^2, in particular 40～400Cm ^2, especially when it is 48～250Cm ^2, by providing the vent hole 6 having an area of the range, the bulge occurrence heating tool 1 Effect Can be prevented.

There is no particular limitation on the means for forming the minute ventilation holes 6. For example, a means usually used industrially as a means for forming minute holes can be used. Examples of such means include perforation by laser light irradiation, perforation by a perforation blade having a sharp cutting edge, and perforation by electric discharge machining using a needle electrode. As the laser light, a CO ₂ laser, a YVO ₄ laser, an ultraviolet laser, or the like can be used.

  As shown in FIG. 2, the container 3 is flat because the peripheral edges of the moisture permeable sheet 3 a and the hardly permeable or non-permeable sheet (hereinafter collectively referred to as a hardly permeable sheet) 3 b are joined to each other. It is formed in a bag shape. That is, one side of the container 3 has the moisture-permeable sheet 3a, and the other side has the hardly moisture-permeable sheet 3b. The moisture permeable sheet 3a allows water vapor generated from the heat generating sheet 2 to pass through. However, the hardly moisture-permeable sheet 3b is difficult to pass water vapor or not. That is, water vapor is released to the outside only from one side of the container 3, that is, the moisture permeable sheet 3 a side.

  As the moisture permeable sheet 3a, a film that allows water vapor and air to permeate but hardly permeates water is used. Examples of the moisture permeable sheet include a fine pore type formed by kneading and stretching calcium carbonate, and a paper making type by rolling fibers. The fine pore type is mainly used for reasons such as denseness, content leakage prevention, and temperature control. Examples of the microporous moisture permeable sheet include a polyolefin film having micropores. Since the water vapor is released to the outside through the moisture permeable sheet 3a as described above, the heating tool 1 of the present embodiment is mounted so that the moisture permeable sheet 3a side faces the human body. Therefore, from the viewpoint of enhancing the wearing feeling, as shown in FIGS. 1 and 2, a non-woven fabric 3c, which is a sheet material having a good texture, is disposed on the outer surface of the moisture-permeable sheet 3a. Accordingly, the nonwoven fabric 3c faces the body when the heating tool 1 is used. The moisture-permeable sheet 3a and the nonwoven fabric 3c may be joined at their peripheral edges, or may be partially bonded within the sheet surface. In FIG. 2, the moisture-permeable sheet 3 a provided with the vent holes 6 is covered with the nonwoven fabric 3 c, but this does not hinder the flow of water vapor through the vent holes 6. This is because the nonwoven fabric 3c has extremely high air permeability and moisture permeability.

The moisture permeability is as previously described, also the air permeability of the sheet 3a of the moisture vapor permeable sheet 3a is preferably 8000~15000s / 100cm ^3, and further preferably 8000~12000s / 100cm ^3. If the air permeability is within this range, the heat generation temperature of the heating tool 1 can be appropriately controlled, and a desired duration and an appropriate amount of water vapor can be obtained at the desired heat generation temperature. As will be described later, the moisture permeable sheet 3a, which is a breathable part in the container 3 of the present embodiment, is provided with a vent hole 6, but in the case of measuring the air permeability of the moisture permeable sheet 3a. A portion where the vent hole 6 is not provided is selected as a measurement target.

  On the other hand, as the hardly moisture-permeable sheet 3b, a film that hardly allows water vapor and water to pass therethrough, for example, a polyolefin film or a polyester film that does not have micropores is used. As shown in FIG. 2, a nonwoven fabric 3 d is laminated on the outer surface of the moisture-impermeable sheet 3 b in order to enhance the texture of the heating tool 1. An adhesive layer (not shown) may be formed on the outer surface of the nonwoven fabric 3d as necessary. In that case, the adhesive layer is protected with a protective release paper (not shown) until the heating tool 1 is used.

  The vent hole 6 described above is preferably formed in the moisture permeable sheet 3a as shown in FIG. The reason is as follows. The heating tool 1 of the present embodiment is typically used with the moisture permeable sheet 3a facing the user's skin. Therefore, by providing the ventilation hole 6 in the moisture permeable sheet 3 a, the ventilation hole 6 is blocked by the skin of the user during use of the heating tool 1, and the inflow of air into the container 3 through the ventilation hole 6 is prevented. It is suppressed. As a result, the heat generation of the heat generating sheet 2 during use of the heating tool 1 is stabilized, and abnormal heat generation or the like is prevented. Thereby, the generation of water vapor is stabilized. In order for the oxidizable metal to generate heat uniformly, air must be supplied uniformly. If there is a part where air flows in excessively even at one location, the control of the heat generation temperature becomes unstable and abnormal heat generation occurs. Cause. Therefore, it has been avoided in the technical field as much as possible to form the air holes 6 as provided in the heating tool 1 of the present embodiment in a porous sheet having moisture permeability.

  Although there is no restriction | limiting in particular in the formation position of the ventilation hole 6 in the moisture-permeable sheet 3a, when the ventilation hole 6 is obstruct | occluded successfully by a user's skin during use of the heat generating tool 1, it adheres to a user's skin. It is preferable to form the air holes 6 in a good position, for example, in the central region of the moisture-permeable sheet 3a.

  As described above, the heat generating sheet 2 includes an oxidizable metal, a reaction accelerator, a fibrous material, and an electrolyte, and is in a water-containing state. Specifically, the heat generating sheet 2 of the present embodiment is configured by containing an electrolyte aqueous solution in a molded sheet containing an oxidizable metal, a reaction accelerator, and a fibrous material. As a result of studies by the present inventors, among these various materials, materials that greatly affect the water vapor release characteristics of the heating tool 1 are oxidizable metals, reaction accelerators, and fibrous materials contained in the molded sheet. There was found. Specifically, the amount of the oxidizable metal contained in the molded sheet is preferably 60 to 90% by weight, more preferably 70 to 85% by weight, and the amount of the reaction accelerator is preferably 5 to 25% by weight, more preferably. It is important that the amount of the fibrous material is 8 to 15% by weight, preferably 5 to 35% by weight, and more preferably 8 to 20% by weight. If the amount of these materials is in the above range, desired water vapor release characteristics and temperature duration can be expected. As will be described later, since the molded sheet is preferably obtained by papermaking, it contains 5% by weight or less of moisture in the state after the drying step in the papermaking process.

  The weight ratio of the reaction accelerator and the fibrous material to the oxidizable metal also affects the water vapor release characteristics of the heating tool 1. Specifically, in the heat generating sheet 2, the weight ratio of the reaction accelerator to the oxidizable metal is preferably 0.08 to 0.3, and more preferably 0.09 to 0.25. The weight ratio of the fibrous material to the oxidizable metal is preferably 0.08 to 0.3, and more preferably 0.09 to 0.29. Within these ranges, it is easy to improve the skin surface temperature to 38 ° C. or higher and to obtain a desired amount of water vapor, and after opening the pillow bag containing the heating tool 1, to the target temperature. It is easy to provide water vapor at an appropriate temperature for 3 hours or longer.

  Other important factors that affect the water vapor release characteristics of the heating tool 1 include the concentration of the aqueous electrolyte solution in the heating sheet 2 and the amount of the aqueous electrolyte solution added. Specifically, the concentration of the aqueous electrolyte solution in the heat generating sheet 2 is preferably 1 to 15% by weight, more preferably 2 to 10% by weight. If the concentration of the aqueous electrolyte solution is within this range, an economically desired temperature can be obtained. The electrolyte aqueous solution is preferably added in an amount of 30 to 80 parts by weight, more preferably 40 to 70 parts by weight, based on 100 parts by weight of the molded sheet. Within this range, the desired temperature can be maintained and a water vapor generation amount can be obtained.

  The details of each material included in the heat generating sheet 2 will be described. Examples of the oxidizable metal include powders and fibers of iron, aluminum, zinc, manganese, magnesium, calcium, and the like. Among these, iron powder is preferably used in terms of handleability, safety, and manufacturing cost. When the oxidizable metal is a powder, the particle size is preferably 0.1 to 300 μm because the fixing property to the fibrous material and the control of the reaction are good. For the same reason, it is also preferable to use a material having a particle size of 0.1 to 150 μm containing 50% by weight or more.

  As the reaction accelerator, it is preferable to use a reaction accelerator that functions as a water retention agent and also has a function as an oxygen retention / supply agent for the oxidizable metal. For example, activated carbon (coconut shell charcoal, charcoal powder, calendar bituminous coal, peat, lignite), carbon black, acetylene black, graphite, zeolite, perlite, vermiculite, silica and the like can be mentioned. Among these, activated carbon is preferably used because it has water retention ability, oxygen supply ability, and catalytic ability. The particle size of the reaction accelerator is preferably 0.1 to 500 μm from the viewpoint that it can effectively contact the oxidizable metal. For the same reason, it is also preferable to use a material containing 50% by weight or more of 0.1 to 200 μm.

  As the fibrous material, a natural or synthetic fibrous material can be used without any particular limitation. Examples of natural fibers include cotton, kabok, wood pulp, non-wood pulp, peanut protein fiber, corn protein fiber, soy protein fiber, mannan fiber, rubber fiber, hemp, manila hemp, sisal hemp, New Zealand hemp, rabu hemp, Plant fibers such as eggplant, igusa and straw are listed. Further, animal fibers such as wool, goat hair, mohair, cashmere, alkapa, Angola, camel, vicuuna, silk, feathers, down, feather, algin fiber, chitin fiber, and casein fiber can be mentioned. Furthermore, mineral fibers, such as asbestos, are mentioned. On the other hand, examples of the synthetic fibrous material include semi-synthetic fibers such as rayon, viscose rayon, cupra, acetate, triacetate, oxide acetate, promix, chlorinated rubber, and hydrochloric acid rubber. Moreover, synthetic polymer fibers such as polyester such as nylon, aramid, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, and polyethylene terephthalate, polyacrylonitrile, acrylic, polyethylene, polypropylene, polystyrene, and polyurethane. Furthermore, metal fiber, carbon fiber, glass fiber, etc. can also be used. Moreover, the collection | recovery reuse goods of these fibers can also be used. Among these, wood pulp, cotton, and polyester are preferably used from the viewpoints of fixability with an oxidizable metal and a reaction accelerator, flexibility of the heat generating sheet 2, oxygen permeability, production cost, and the like. The fibrous material preferably has an average fiber length of 0.1 to 50 mm, particularly 0.2 to 20 mm, from the viewpoint of securing the strength of the heat generating sheet 2 and the water dispersibility of the fibrous material.

  The fibrous material preferably has a CSF (Canadian standard drainage test method JIS P8121) of 600 ml or less, more preferably 450 ml or less. Thereby, the fixing property between the fibrous material and the oxidizable metal becomes good, and the heat generating property of the heat generating sheet 2 can be made good. Moreover, it becomes easy to adjust the tearing length described later within a range described later, and as a result, the oxidizable metal can be removed from the heat generating sheet 2 and the mechanical strength of the heat generating sheet 2 can be appropriately maintained. it can. The lower the CSF of the fibrous material, the better. However, when only normal pulp fiber is used as a fibrous material and papermaking is performed as a raw material, when the component ratio other than the fibrous material is low, if the CSF is less than 100 ml, the drainage tends to deteriorate, and dehydration Becomes difficult to obtain a heat-generating sheet having a uniform thickness. Also, molding defects such as blister breakage may occur during drying. On the other hand, in the heat generating sheet 2, since the ratio of components other than the fibrous material is relatively high, the heat generating sheet 2 having good drainage and uniform thickness can be obtained. Moreover, since the fibril increases as the CSF decreases, the fixability between the fibrous material and components other than the fibrous material is improved, and a high sheet strength can be obtained. Adjustment of the CSF of the fibrous material can be performed by a beating process or the like. CSF may be adjusted by mixing low and high CSF fibers.

  Examples of the electrolyte include alkali metal, alkaline earth metal or transition metal sulfates, halides, and the like. Among these, chlorides of alkali metals, alkaline earth metals or transition metals are preferably used from the viewpoint of excellent chemical stability and production cost, especially sodium chloride, potassium chloride, calcium chloride, magnesium chloride, ferrous chloride. Ferric chloride is preferably used.

  Additives usually used in papermaking, such as a flocculant, a sizing agent, a colorant, a paper strength enhancer, a yield improver, a filler, a thickener, a pH control agent, a bulking agent, etc. A thing can also be added without a restriction | limiting in particular.

  There is no restriction | limiting in particular in the manufacturing method of the heat generating sheet 2. FIG. Since the exothermic sheet is formed by adding an aqueous electrolyte solution to a molded sheet containing an oxidizable metal, a reaction accelerator and a fibrous material, it first contains an oxidizable metal, a reaction accelerator and a fibrous material. A heat generating sheet is obtained by forming a molded sheet and adding an aqueous electrolyte solution to the molded sheet. For the production of the molded sheet, for example, a wet papermaking method described in Japanese Patent Application Laid-Open No. 2003-102761 or an extrusion method using a die coater according to the previous application of the present applicant can be used. In particular, it is preferable to use a wet papermaking method from the viewpoint of manufacturing cost and productivity. When performing the wet papermaking method, a circular paper machine, a long paper machine, a short paper machine, a twin wire paper machine, or the like can be used. The slurry used for papermaking contains an oxidizable metal, a reaction accelerator, a fibrous material, and water, and its concentration is 0.05 to 10% by weight, particularly 0.1 to 2% by weight. Is preferred.

  From the point which maintains the form after papermaking, and the point which maintains mechanical strength, the molded sheet obtained by papermaking has a moisture content (weight moisture content, the same shall apply hereinafter) until 70% or less, particularly 60% or less. It is preferable to dehydrate. Examples of the method for dewatering the formed sheet after papermaking include dewatering by suction, a method of dehydrating by blowing pressurized air, a method of dehydrating by pressing with a pressure roll or a pressure plate, and the like.

  The dehydrated molded sheet is preferably dried by heat drying. The heating and drying temperature is preferably 60 to 300 ° C, particularly 80 to 250 ° C. The moisture content of the molded sheet after drying is more preferably 20% or less, particularly 10% or less. The dehydration and / or drying of the molded sheet is preferably performed in an inert gas atmosphere from the viewpoint of suppressing oxidation of the oxidizable metal. However, since the molded sheet does not contain an electrolyte serving as an oxidation aid, it can be molded in a normal air atmosphere as necessary. This is advantageous because the production equipment can be simplified. The molded sheet after drying contains an oxidizable metal, a reaction accelerator and a fibrous material, preferably 60 to 90% by weight of the oxidizable metal, more preferably 70 to 85% by weight, and a reaction accelerator. 5 to 25% by weight, more preferably 8 to 15% by weight, and 5 to 35% by weight, more preferably 8 to 20% by weight of fibrous material.

The molded sheet thus obtained (that is, the exothermic sheet 2 in a state before being hydrated) has a thickness of 0.1 mm to 2 mm, particularly 0.15 to 1.5 mm. It is preferable in that the molded sheet becomes flexible while maintaining the desired strength, and the heating tool 1 can be easily fitted to the application site of the body. Molded sheet for the same reason, it is preferable that the basis weight of 10 to 1000 g / m ^2, more preferably from 50~600g / m ^2, and still more preferably from 100 to 500 g / m ^2.

The molded sheets may be used by overlapping a plurality of sheets as they are, or may be used by stacking a plurality of molded sheets folded and folded. In this case, in order to prevent positional deviation between the sheets during use of the heating tool 1, it is preferable to integrate the sheets by embossing. Further, it is possible to prevent the positional deviation from occurring by giving the above-described holes and cuts to the sheet. The weight ratio of the molded sheet with respect to the area of the heating tool 1 is preferably 0.03 g / cm ^{2 to} 0.17 g from the viewpoint that desired temperature sustainability can be achieved, fit is good, and manufacturing problems are unlikely to occur. / cm ^2, more preferably from ^{0.06g / cm 2 ~0.14g / cm 2} . For the same reason, the ratio of the weight per unit area of the oxidizable metal is preferably ^{0.02g / cm 2 ~0.14g / cm 2} , more preferably 0.04g / cm ² ~0.12g / cm ² .

  The molded sheet thus obtained contains an aqueous electrolyte solution to obtain a heat generating sheet 2. This step is preferably performed in an inert gas atmosphere such as nitrogen or argon. In order to contain the electrolyte aqueous solution, for example, a method by directly discharging from a nozzle, a spray coating method, a method of coating with a brush, a method of immersing in an electrolyte aqueous solution, a gravure coating method, a reverse coating method, a doctor blade method and the like can be mentioned. . The concentration of the electrolyte in the aqueous electrolyte solution and the applied amount of the aqueous electrolyte solution are adjusted so that the amount of the electrolyte and the water content in the resulting heat generating sheet 2 are in the ranges described above.

The obtained heat generating sheet 2 is housed in the housing 3 to form the heat generating tool 1. The heating tool 1 is preferably sealed in a packaging bag made of an oxygen-barrier material to form a packaging bag containing a heating tool as the final product. When the heating tool 1 is used, by removing the heating tool 1 from the packaging bag, the oxidizable metal contained in the heating tool 1 reacts with oxygen in the air, heat generation starts and water vapor is generated. As an oxygen barrier material, for example, its oxygen permeability coefficient (ASTM D3985) is 10 cm ³ · mm / (m ² · d · MPa) or less, particularly 2 cm ³ · mm / (m ² · d · MPa) or less. Such a thing is preferable. Specific examples include ethylene-vinyl alcohol copolymer and polyacrylonitrile.

  The heating tool 1 of the present embodiment is used by being mounted on, for example, the waist or shoulders of a human body, thereby obtaining effects such as improvement of blood circulation of the whole body, recovery from fatigue, and elimination of muscle stiffness. An example of the usage pattern of the heating tool 1 is shown in FIG. The heating tool 1 is used by being fixed to a belt-like fitter 5 for body wearing. A pocket (not shown) for housing the heating tool 1 is formed at the center of the fitter 5. One end portion is provided with a fastening portion such as a hook-and-loop fastener. The fastening part is fastened to the other tip part. When using the heating tool 1, first, the heating tool 1 is accommodated in the pocket of the fitter 5. At this time, the moisture permeable film side in the heating tool 1, that is, the side having air permeability and moisture permeability is set to face the user's body.

  In the above embodiment, the heat generating sheet 2 is used as the heat generating material, but heat generating powder can be used instead. The exothermic powder, like the exothermic sheet 2, contains an oxidizable metal, a reaction accelerator, an electrolyte, and water. However, the exothermic sheet 2 contains a fibrous material in addition to these components, whereas the exothermic powder contains a water retention material instead of the fibrous material. Examples of water retention agents include water-absorbing polymers, vermiculite, calcium silicate, silica gel, and alumina. Among these, it is preferable to use a water-absorbing polymer from the viewpoints of high retainability and excellent productivity.

  Since the exothermic powder is mainly intended to generate water vapor in the same manner as the exothermic sheet 2, it is suitable that the exothermic powder is in a high water content state. The composition of the exothermic powder is, for example, 30 to 80% by weight of oxidizable metal, 3 to 25% by weight of a reaction accelerator such as activated carbon, 3 to 25% by weight of a water retention agent such as a water-absorbing polymer or vermiculite, and sodium chloride. The electrolyte is 0.3 to 12% by weight, and the water is 20 to 60% by weight.

  The present invention is not limited to the embodiment. For example, in the above-described embodiment, the air holes 6 are formed in the moisture-permeable sheet 3a in the container 3. However, if it is expected that the heat generation in a stable state and abnormal heat generation can be expected, the hardly moisture-permeable sheet 3b. A vent hole may be provided on the side.

  Moreover, in the said embodiment, although the container 3 was comprised from what bonded the moisture-permeable sheet 3a and the hardly moisture-permeable sheet 3b in the bag shape, it replaces with this and the periphery of two moisture-permeable sheets It is also possible to use a container formed in a bag shape by joining the two. In this case, water vapor is generated from each surface of the container.

  The heating tool of the above embodiment is preferably used by being attached to the waist or shoulder of the human body from the viewpoint of an increase in deep temperature, but other parts of the human body, such as the neck, shoulder, back, abdomen, elbow, You may apply to a knee etc. Furthermore, the present invention may be applied to skin care applications such as facial and body washing, sterilization, and makeup removal. In addition to being worn on the human body, combined with various functional agents such as cleaning / sterilization, sustained release of wax, fragrance, and deodorization, flooring, folding, around the range, house care applications such as ventilation fans, washing of cars, etc. It can also be applied to car care applications such as.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited to such examples.

[Examples 1 to 4 and Comparative Examples 1 to 2]
<Slurry blending>
・ Oxidizable metal: iron powder, manufactured by Dowa Iron Mining Co., Ltd., trade name “RKH”, 150 g
-Fibrous material: Pulp fiber (NBKP, manufactured by Schina Co., Ltd., trade name “Skina”, average fiber length = 2.1 mm), 30 g
-Reaction accelerator: activated carbon, manufactured by Nippon Enviro Chemicals Co., Ltd., trade name “Carborafyn”), 20 g
Flocculant: sodium carboxymethyl cellulose (Daiichi Kogyo Seiyaku Co., Ltd., trade name “Serogen” WS-C) 0.5 g, and polyamide epichlorohydrin resin (Seiko PMC Co., Ltd., trade name “WS4020”) 0.5g
・ Water: Industrial water, 99800g

<Paper making conditions>
Using the slurry, paper was made at a line speed of 7 m / min with a slanted short net paper machine to produce a wet shaped sheet.

<Dehydration and drying conditions>
It was sandwiched with felt and dehydrated under pressure, passed through a heating roll at 120 ° C. at a line speed of 7 m / min, and dried until the water content became 5% by weight or less to obtain a molded sheet.

<Electrolytic aqueous solution addition conditions>
After stacking four obtained molded sheets, a predetermined amount of the following electrolyte aqueous solution was impregnated to prepare a heat generating sheet. Table 1 shows the moisture content of the exothermic sheet and the blending ratio of each component in the exothermic sheet.

<Electrolyte>
Electrolyte: Purified salt (NaCl)
Water: Industrial water Electrolyte concentration: 5% by weight

<Containment in container>
A rectangular container 3 shown in FIGS. 1 and 2 was manufactured. As the moisture-permeable sheet 3a, a moisture-permeable film made of polyethylene (TSF-EU manufactured by Kojin Co., Ltd .: moisture permeability of 900 g / m ² · 24 hr, air permeability of 10,000 seconds / 100 cm ³ ) was used. A laminate of a spunbonded nonwoven fabric (Elves manufactured by Unitika Ltd., basis weight 30 g / m ² ) and a low density polyethylene film (basis weight 34 g / m ² ) was used as the hardly moisture permeable sheet 3b. As the nonwoven fabric 3c, a spunbond nonwoven fabric (Elves manufactured by Unitika Ltd., basis weight 30 g / m ² ) was used. The area of the moisture-permeable sheet 3a was as shown in Table 2. A through-hole was formed with a needle in the center of the moisture-permeable sheet 3a. Table 2 shows the number of holes and the equivalent circle diameter. The exothermic sheet was accommodated in this container. Thereby, the heating tool shown in FIG.1 and FIG.2 was obtained.

[Performance evaluation]
About the heating tool obtained by each Example and each comparative example, the moisture content of the heat generating sheet after completion | finish of heat_generation | fever was measured by the method described above. Moreover, the swelling of the heating tool after completion of heat generation was evaluated by the following method. Furthermore, the following methods evaluated the warmth and the presence or absence of powder leakage. These results are shown in Table 2.

[Bulge of the heating tool after the end of heat generation]
After the end of heat generation, the heating tool was left in an environment of 20 ° C. and 50% RH for 4 hours. Thereafter, the height of the heating tool was measured. When the height was less than 1 cm, it was judged that there was no swelling, and when it was 1 cm or more, it was judged that there was swelling.

[Warm feeling]
In an environment of 20 ° C and 40% RH, apply a heating tool to 10 subjects for 60 minutes with the moisture permeable surface facing the skin, and listen to the feeling that the whole body is warmed during the application by "warming up, not warming up" It was. A case where 6 or more subjects answered that they were warmed was marked as ◯, and a case where 6 or more subjects answered that they were not warmed was marked as x.

[Powder leakage]
The container was vibrated 10 times while still in the packaging bag, and it was examined whether the contents leaked out from the vicinity of the opening or not. Among the 10 samples, the case where the contents leaked with 6 or more samples was marked with ×, and the case where the contents were not leaked with 6 or more samples was marked with ○.

It is a perspective view which shows one Embodiment of the heat generating tool 1 of this invention. FIG. 2 is a sectional view taken along line II-II in FIG. It is explanatory drawing explaining the principle which the heating tool of this embodiment swells after completion | finish of heat_generation | fever. It is a figure which shows an example of the usage condition of the heat generating tool shown in FIG. It is a figure which shows the use condition of the heat generating tool shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heating tool 2 Heating sheet 3 Container 5 Belt-like fitter 6 Vent

Claims (7)

In a container provided with a breathable portion made of a microporous moisture-permeable sheet or a paper-making moisture-permeable sheet having a moisture permeability (JIS Z0208, 40 ° C., 90% RH) of 200 to 2000 g / m ² · 24 hr. Contains heat-generating materials containing oxidizable metals that can generate heat by contact with air,
The heat-generating material has a water content of 10 to 70% by weight after completion of heat generation,
The container has an area of a breathable portion of 30 to 600 cm ² , and the container is provided with a vent hole having a circle equivalent diameter of 50 μmΦ to 400 μmΦ that communicates the inside and outside of the container. Is a heating tool having a thickness of 2000 to 126000 μm ² . Water vapor generated from the heat generating material is released to the outside of the container through the breathable portion, and the cumulative amount of water vapor released 90 minutes after the heat generating material comes into contact with air is 1.4. The heating tool according to claim 1, which is ˜7.0 mg / cm ² .   The heating tool according to claim 1 or 2, wherein the heating material is a heating sheet or a heating powder containing an oxidizable metal, a reaction accelerator, an electrolyte, and water.   The exothermic sheet is a molded sheet containing 60 to 90% by weight of an oxidizable metal, 5 to 25% by weight of a reaction accelerator, and 5 to 35% by weight of a fibrous material, with respect to 100 parts by weight of the molded sheet. The heating tool according to claim 3, wherein 30 to 80 parts by weight of an aqueous electrolyte solution containing 1 to 15% by weight of the electrolyte is contained. The container is formed in a bag shape by stacking the moisture-permeable sheet having moisture permeability and the hardly moisture-permeable or non-moisture-permeable sheet on each other, and joining the peripheral edges of both sheets to each other. The heating tool according to any one of claims 1 to 4 , wherein the ventilation hole is formed in a sheet. The heating tool according to claim 5, which is used with the moisture permeable sheet side of the container facing the user's skin. The heating tool according to any one of claims 1 to 6, wherein the number of the air holes is 1 to 3.