JP2007319512A - Heating body and heating implement with selectable heating temperature - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heating body and a heating implement using the same allowing a user to freely and simply select a desired temperature in using in either direction from a high temperature side to a low temperature side or inversely from the low temperature side to the high temperature side. <P>SOLUTION: This heating body which is formed by sealing a heating composition producing heat in the presence of air into a flat bag formed of a sheet having permeability at least in parts of the respective faces, is characterized in that a difference of mean surface temperatures of the both faces measured by a heat board face method is 2.0°C or more. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heating element and a heating tool. In particular, the present invention relates to a heating element capable of selecting different temperatures by changing the direction of the surface, a heating tool using the heating element, and the like.

  A heating element comprising a breathable bag containing a heat-generating composition that generates heat upon contact with air, and a heating device using the same, are intended to alleviate chronic pain due to stiff shoulders, neuralgia, muscle pain, etc. and various causes. In general, it is widely used as a medical tool or a warmer for cold protection. Usually, such heating elements are used with one side facing the air and the other side facing the skin.

  The exothermic composition generally used for such a heating element generates heat by the reaction of oxygen, iron and water. Since a certain amount of water and iron necessary for this reaction are mixed at the time of production, the reaction amount (heat generation amount) is proportional to the amount of oxygen (air) entering from the outside. Therefore, if the exothermic composition is the same, the exothermic temperature is considered to be proportional to the air permeability of the air permeable sheet constituting the air permeable bag.

  Regarding such a heating element, it is conventionally known that one side is constituted by a breathable sheet and that both sides are constituted by a breathable sheet.

  When both sides of the breathable bag are made breathable, air enters from both sides in terms of configuration. However, when the heating element is used in close contact with the human body, a large amount of air enters from the air side, and air can enter only from the gap between the skin and the heating element from the skin side. It is considered that the air permeability is greatly influenced by the air permeability of the air permeable sheet constituting the air side surface, and it is considered that the skin side surface does not substantially contribute to heat generation.

  On the other hand, a usage mode in which there is a large gap between the heating element and the human body (for example, in a case where the gap between the heating element and the skin can be increased due to movement of the human body, or in close contact with the skin side) ), Air also enters from the skin side, so the difference in the amount of air entering from both the air side and the skin side is reduced. In addition, since the heating element is thin and the content is powder, the air in the heating element is easy to move, and the amount of air entering from both sides is further reduced.

  For this reason, it has been considered that a heating element having air permeability on both sides is substantially the same as that on one side, or both sides generate heat similarly.

  Most heating elements currently in practical use are designed in advance to exhibit a constant heating temperature. As a heating element capable of exhibiting two or more temperatures with one heating element, a plurality of ventilation holes with partial cuts are provided on the surface of the ventilation membrane so that the user can selectively peel off. There has been proposed a warmer capable of adjusting the heat generation temperature by the above method (for example, Patent Document 1).

  Moreover, as a heat generating body which has air permeability on both surfaces, for example, a foot warmer or a heat generating body in which wet heat accompanied by water vapor generated from the surface due to heat generation hits the skin has been proposed (for example, Patent Documents 2 to 6). However, these heating elements having air permeability on both sides have no difference in air permeability on both sides, and there are two or more wet heat-type heating elements or heating devices actually used, and warmers for feet. It was not designed to exhibit an exothermic temperature of.

JP 2003-70827 A Japanese Utility Model Publication No.59-19818 Japanese Utility Model Publication No. 58-22735 Japanese Utility Model Publication No.2-136044 Japanese Examined Patent Publication No. 56-85336 JP 2005-224314 A

  The conventional heating element capable of adjusting the exothermic temperature as described above requires a troublesome operation of removing the cut portion for temperature adjustment, and can only remove the cut portion when changing the exothermic temperature. There was a drawback that it could only be changed to a higher temperature direction. Furthermore, the adhesive remains in the removed part, and there are problems such as sticking to clothes that come into contact with it, and the problem of high manufacturing costs, and it has not been put to practical use.

  A first object of the present invention is a heating element capable of easily and freely selecting a desired temperature in either direction from the high temperature side to the low temperature side, and conversely from the low temperature side to the high temperature side during use, and It is to provide a heating tool using the same at a manufacturing cost comparable to the conventional one.

The present inventors have found that the above-mentioned object can be easily achieved by configuring both surfaces of a heating element with a combination of breathable sheets satisfying specific conditions, and have completed the present invention.
That is, according to the present invention,
[1] A heating element in which a heat generating composition that generates heat in the presence of air is encapsulated in a flat bag made of a breathable sheet having at least part of each surface breathable, and measured by the following method. The heating element characterized in that the difference between the average surface temperatures of the two surfaces is 2.0 ° C. or more:
Measurement of surface temperature by hot plate method: A cloth having an average thickness of 550 ± 30 μm and an average basis weight of 185 ± 10 g / m ² is laid on a hot plate surface maintained at a temperature of 30 ± 1 ° C., and heat is generated thereon. A body is placed to generate heat, and the surface temperature of the heating element on the board surface side is measured by a temperature sensor installed between the cloth and the board surface.
Average surface temperature calculation method: As a result of the measurement by the hot plate surface method, the average surface temperature is calculated by averaging the temperatures in a period of 38.0 ° C. or higher;
[2] The heating element according to the above [1], wherein both sides of the flat bag are respectively configured with a high air permeability sheet A and the other with a low air permeability sheet B;
[3] When the air permeability according to the Gurley method (JIS-P8117) of the breathable sheets A and B is a and b (seconds / 100 cc), respectively.
b-2a ≧ 3,000 (Formula-1)
The heating element according to [2], wherein
[4] Breathability a and b by the Gurley method (JIS-P8117) of the breathable sheets A and B are:
a ≧ 7,000 (Formula-2)
And b + 2.7a ≦ 97,000 (Formula-3)
The heating element according to [2] or [3], wherein
[5] The heating element according to any one of [1] to [4], wherein the average surface temperature is 38.0 to 48.0 ° C. for each of both surfaces;
[6] A heating tool including the heating element according to any one of [1] to [5] as a constituent element;
[7] The heating device according to [6], which includes at least two layers of holding members, and includes a combination of the support and the heating element for sandwiching and using the heating element between the holding members. ;
[8] The heating tool according to [7], wherein the supporter is for knees;
[9] A supporter for mounting the heating element according to any one of [1] to [5], including at least two layers of holding members, wherein the heating element is provided between the holding members. Supporters that can be sandwiched,
Is provided.

The heating element of the present invention has the following effects.
(1) Since both sides of the heating element generate heat at different temperatures, one of the two temperatures can be easily selected and used according to the user's preference by simply changing the side facing the skin.
(2) During use, the temperature to be freely selected can be changed any number of times from the low temperature side to the high temperature side or from the high temperature side to the low temperature side.
(3) The heat generation is more stable and the difference between the maximum heat generation temperature and the average heat generation temperature tends to be smaller than that of a known heat generation element such as a heat generation element having the same air permeability on both sides and air permeability on both sides, and can be used comfortably. .
(4) Since wet heat is transmitted to the skin side, drying of the skin especially in winter is suppressed, and itching by a supporter and the like is prevented, which is good for health. In addition, the conventional heating element dissipates water vapor (wet heat) together with heat from the holes on the ventilation surface, but the air side is normally the ventilation surface, whereas the heating element of the present invention is breathable on both sides, Moist heat is also dissipated from the ventilation surface on the skin side and hits the skin. Moist heat replenishes the skin and warms it to the deep part of the body with a soft heat feeling at an appropriate temperature, which is good for your health.
(5) During use and after completion of heat generation, little or no heat generation composition is cured, and there is little discomfort.

  The heating element of the present invention is basically composed of a flat bag made of a sheet having air permeability on both sides, and a heating composition enclosed in the bag.

  The exothermic composition enclosed in the flat bag in the present invention may be any composition that generates heat upon contact with oxygen (air), and a conventionally known one can be used, and its production method is also well known. In general, metal powder such as iron powder that generates heat due to oxidation reaction and water are essential components, and water retention such as activated carbon, inorganic chlorides such as salt and potassium chloride, and water-absorbing polymers, vermiculite, sawdust, silica-based substances, etc. A composition containing an agent or the like is used. For example, assuming that the weight of the exothermic composition is 100%, iron consists of 35 to 80% by weight, activated carbon 1 to 10% by weight, chloride 1 to 10% by weight, water 5 to 45% by weight, and water retaining agent 1 to 45% by weight. Things. The exothermic composition is generally a powder (including particulates), but may be formed into a sheet by means of alcohol inclusion, pressurization or the like (for example, JP-A 2000-60886, WO 00 / 13626).

  In the present invention, the breathable sheet used for the flat bag may be a film or sheet that is completely or partially breathable. Generally, a single-layer or laminated porous film or sheet is used alone, or Used in combination with woven or non-woven fabrics. In the present invention, “film” mainly refers to a simple substance (including a single layer and a laminate; the same shall apply hereinafter) or relatively thin, and “sheet” mainly refers to a simple substance or a laminate of two or more simple substances or a relatively thick one. Strictly do not distinguish.

  In general, a thermoplastic synthetic resin or the like is used as the resin constituting the film. Specifically, polyethylene, polypropylene, polyester, polyamide, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, polyurethane, polystyrene, ethylene-vinyl acetate copolymer, polycarbonate, hydrochloric acid rubber and the like are preferably used alone or in combination. It is done. Depending on the purpose, it can be appropriately selected according to the necessary required calorific value, temperature, exothermic composition to be used and the like.

  In the present invention, as the breathable film, a stretched film, preferably a stretched porous film or a sheet containing the stretched film is suitably used. The stretched porous film generally contains an inorganic filler, and air permeability is expressed by forming communication holes by stretching. The air permeability can be controlled by controlling the pore diameter and the like. Preferred are white or milky white olefinic (particularly polyethylene) stretched porous laminated films and composite (laminate) sheets of these with nonwoven fabrics.

  In the case of laminating, it is usually performed by a laminating method, but is not limited thereto. Any conventionally known method can be applied to the laminate. For example, it may be a method of laminating with an adhesive such as thermal bonding or hot melt adhesive or acrylic or urethane adhesive, and may be full-surface bonding or partial bonding to maintain flexibility. A curtain spray method or a dry laminating method is preferably used.

As the nonwoven fabric that may be laminated with the above film, those conventionally used in technical fields such as a heating element and a medical heating tool can be suitably used. Examples include those containing artificial fibers such as nylon, vinylon, polyester, rayon, acetate, acrylic, polyethylene, polypropylene and polyvinyl chloride, and natural fibers such as cotton, hemp and silk. The basis weight of the nonwoven fabric is preferably about ²⁰ to 100 g / m ² .

  In particular, a breathable sheet obtained by laminating a nonwoven fabric such as nylon or polyester fiber on a stretched porous film of a thermoplastic synthetic resin is generally used in many cases.

  The air permeability of the breathable sheet can be selected by selecting a film or sheet having a desired air permeability. The air permeability of the porous film can be easily changed by changing production conditions such as stretching conditions as described above, and various commercially available products can also be used. Also, the air permeability can be adjusted by processing or combining films or sheets.

The sheets constituting both surfaces are, for example, a non-breathable sheet for a part of the sheets constituting each surface, or by performing processing such as printing or forming an adhesive layer, etc. The part may be non-breathable. However, from the viewpoint of uniform heat generation on the entire surface, it is preferable that the entire surface has air permeability uniformly. Here, “uniform over the entire surface” means that when the air permeability is measured by the Gurley method at three or more different positions on the entire surface, the average of three or more measured values at each position is It means that it is in the range of 0.5 to 2 times the average value of measured values. Accordingly, it is preferable that the non-breathable portion generated by processing such as printing or the formation of an adhesive layer is uniformly arranged on the entire surface with a pattern as fine as possible.
As the non-breathable sheet, a sheet having the same material and configuration as described above for the breathable sheet and having substantially no breathability can be used. In addition, when a part is non-breathable, the air permeability may be measured for the breathable part.

  The material and configuration of the breathable sheet used on both sides of the flat bag may be the same or different.

  In the present invention, the combination of sheets used on both sides is that when a heating element using two types of sheets to be tested on each side is prepared and the heating temperature is measured by the hot platen method described below, It is selected so that the difference between the average surface temperatures when the exothermic temperature of 38.0 ° C. or higher on the surface is measured is 2.0 ° C. or higher.

<Hot plate surface method>
As the exothermic composition, two exothermic bodies having a size of 70 mm × 95 mm containing 13.5 g of the following composition are prepared for each type of breathable sheet. The heat generation characteristics when the surface of each sheet is on the air side (or the board surface side) are measured by the following method.

  Composition of exothermic composition: iron powder 55.0 g, activated carbon 7.0 g, NaCl 2.0 g, water 29.9 g, water-absorbing polymer 3.0 g, vermiculite 3.1 g; or those exhibiting equivalent exothermic characteristics.

At room temperature 25 ± 1 ° C, hot water circulation type PVC hot plate (material: PVC (thickness 8mm), dimensions: horizontal 615 x vertical 410 x height 60mm), set use temperature 30 ° C (hot plate 30 ° C; Connected with a constant temperature water bath (Yamato Scientific Co., Ltd .; Thermomate BF200 or equivalent) and piping (outside diameter about 18mm PVC, JIS K6741, nominal diameter 13mm) with temperature control accuracy ± 0.05-0.1 ° C) At 30 ° C. On this hot platen, a small thin platinum side temperature resistor (surface temperature measuring side temperature resistor R060-32 (manufactured by Chino Co., Ltd.), resistance element Pt100, specified current 2 mA, sensor part 14 × 25.5 × thickness. 0.8 mm thick, sheet-like silicone mold; or equivalent), and cloth (average thickness is 550 ± 30 μm, average weight is 185 ± 10 g / m ² , 97% nylon and 3% polyurethane) (Meanwhile, the average thickness of the fabric is 30 points measured with a dial thickness gauge (dial gauge type: model G-6, manufactured by Ozaki Seisakusho) or equivalent, 2) is cut to a size of 100mm wide x 120mm long, and the vertical and vertical locations are fixed to the board surface with tape.The heating element is placed flat on this cloth, and the horizontal and horizontal locations of the heating element are fixed with tape. Secure to cloth The entire measurement object is covered with a windbreak case that allows air to flow outside while securing the surrounding space, and the temperature is measured with a hybrid recorder (manufactured by Chino Corp .; dot type, AH3725N00 or equivalent). Are recorded continuously.

<Calculation method of average surface temperature>
The average surface temperature is calculated in accordance with the “Average Temperature” section of the Consumer Affairs Department, Tokyo Metropolitan Life and Culture Bureau, “Guidelines for Quality Labeling (Used Cairo)” (1982). However, the measured value every 10 minutes during the period from 38.0 ° C. after the start of heat generation to below 38.0 ° C. is used, and the number of measurements is 5 times. Each measured value is expressed with one decimal place.
Specifically, from the result obtained by the above measurement, the measurement value T ₁ , T ₂ ,... Every 10 minutes is selected as the measurement start time (0 minute) when the time point reaches 38.0 ° C. when it becomes less than 38.0 ° C. (exothermic termination) immediately before the measurement to T _n (i.e., all measurements were temperature above 38.0 ° C.) to sum. Numerical values calculated by dividing the total T _sam (= T ₁ + T ₂ +... + T _n ) by the number n of the total measured values are collected in five tests, and the average value thereof is expressed as “average surface temperature”. (Also called average temperature).
The average surface temperature for both surfaces is obtained as described above, and the difference (absolute value) is defined as “average surface temperature difference” (also referred to as average temperature difference).
As a result of the above measurement, the temperature at the point showing the highest temperature (the average value of the measured values from five tests) is defined as the “maximum temperature”.

  In the above measurement method, setting the board surface to 30 ° C. (± 1) ° C. mimics the human skin temperature in a normal temperature environment, and measuring the temperature on the board surface side of the heating element is exothermic This is to mimic measuring the temperature on the skin side of the body. The average temperature of 38.0 ° C. or higher is adopted because 38.0 ° C. is considered to be the lower limit for feeling warmth when a heating element or heating tool is applied to the human body (particularly the knee surface). is there.

In the measurement method described above, the inventors actually measured that the difference in average surface temperature when the orientation of the surface of a double-sided air-permeable heating element having different air permeability on both sides was 2.0 ° C. or more was actually It has been found that a temperature difference can be experienced when used as a heating tool.
It is preferable to create such a temperature difference between both sides by configuring both sides of the flat bag, one of which is a highly breathable sheet A and the other is a low breathable sheet B.

In general, when the air-side ventilation surface and the skin-side ventilation surface of the heating element are compared, the air side can contact the air relatively freely. Therefore, the amount of air taken into the heating element (and the air) The side heating element surface temperature) greatly depends on the air permeability of the air side sheet.
On the other hand, the temperature of the skin-side heating element surface is (i) the amount of air movement from the air side to the skin side, (ii) heat conduction from the air side, (iii) the exothermic reaction of the exothermic composition on the skin side, (iv) It is affected by the release of wet heat from the skin side to the outside.
While these phenomena occur, if the air permeability falls below the point of air permeability (the value of air permeability according to the Gurley method increases), the amount of air (oxygen) consumed in the bag cannot be supplied from the outside, The bag is under reduced pressure. As a result, the exothermic composition powder becomes difficult to move in the bag, and at the same time, due to heat generation, the powder gradually hardens and solidifies, so that the amount of air movement from the air side to the skin side in (i) above is reduced. Less. Thus, the temperature difference between the air side and the skin side increases. Therefore, this tendency is considered to increase as the difference in air permeability between the two surfaces increases.

  The above phenomenon tends to be alleviated by the movement of the human body using the heating element, but this tendency is basically unchanged. Therefore, it is considered that by setting the different air permeability on both sides to the above specific range, if the orientation of the surface is changed, a temperature difference appears on the skin side, and this can be experienced as a temperature difference.

Note that the temperature difference between the two surfaces can also be created by disposing the high temperature exothermic exothermic composition and the low temperature exothermic exothermic composition on both sides in the flat bag. In this case, the exothermic composition can be accommodated by partitioning the inside of the bag.
In addition, the temperature difference between the two surfaces may be realized by using any means alone, such as air permeability control and exothermic composition selection as exemplified above, or by combining some of these. May be.

  The air permeability of the air permeable sheet can be measured by the Gurley method (JIS-P8117). Regarding the present invention, the air permeability will be described using the Gurley method air permeability (JIS P-8117, unit: second / 100 cc). The air permeability according to the Gurley method is expressed by the time (seconds) required for 100 cc of air to pass under certain conditions. The smaller the value, the greater the air permeability. The size is reversed. Moreover, you may measure by another method, In that case, it can convert into the measured value by the Gurley method.

  In the heating element of the present invention, when the air permeability of the breathable sheets A and B by the Gurley method is a and b (seconds / 100 cc), respectively, the air permeability a and b is preferably b-2a ≧ 3,000 ( Formula-1). When the difference (b-2a) in the numerical value of air permeability is 3,000 or more, the difference does not become too small. When each of A and B is used on the air side, the hot platen method and the field test (described later) In 1), the difference in average surface temperature is 2 ° C. or more, and it is preferable as a heating element that can experience the temperature difference between both sides when actually used and can selectively use the heating temperature.

  b-2a ≧ 3,000 (Formula-1) is a kind of difference in air permeability indicating that the difference in air permeability between b and a is greater than a certain value. However, a factor of 1 or more is applied to a, which indicates that the influence of the air permeability on the high ventilation side is greater than that on the low ventilation side, not simply how much the difference between a and b is. When the condition of Formula-1 is satisfied, the temperature difference can be actually felt when the surface is changed and applied to the human body.

  The air permeability a of the highly air-permeable sheet A is preferably 7,000 seconds / 100 cc or less (a ≧ 7,000) (Formula-2). When the air permeability a of A is 7,000 seconds / 100 cc or less, when A is set to the air side, the amount of air entering from A does not increase too much, and thus heat generation does not increase too much (average temperature is 48 ° C. or less). Moreover, since blistering does not occur, it is preferable as a heating element of a heating tool.

  In addition, as a heat generating body of a heating tool, it is preferable that the average temperature in a hot-plate surface method is 38-48 degreeC.

  Further, the combination of the breathable sheets A and B preferably satisfies the relational expression b + 2.7a ≦ 97,000 (Formula-3). When b + 2.7a is 97,000 or less, the total amount of air entering from both sides does not become too small, and the average temperature becomes 38 ° C. or more, which is preferable as a heating element for a heating tool.

  b + 2.7a ≦ 97,000 (Formula-3) is a rewrite of b ≦ −2.7a + 97,000, and the meaning of Formula-3 is the sum of the air permeability on both sides. The contribution of air permeability indicates that a is 2.7 times b. That is, if the total amount of air entering from both sides (in which case a has an effect of 2.7 times b) is greater than a certain value, heat generation will be better (average surface temperature will be 38 ° C. or higher), and if it is less, heat will be generated. The average surface temperature is lowered to 38 ° C. or lower.

  The heating element manufacturing method of the present invention may be an ordinary manufacturing method. For example, a flat bag is produced by laminating a sheet or film on the other side (b) on a sheet or film on one side (A), and then generates heat. The composition may be encapsulated, or after placing the exothermic composition on one side (A) sheet or film, the other side (B) sheet or film may be laminated to form a bag. The latter is preferable from the viewpoint of efficiency.

  The heating element thus obtained may be a so-called “do not stick” type heating element that does not use an adhesive, and may be used as a “sticking” type heating element that sticks either side to clothes or skin. Also good. When using an adhesive, it is preferable to apply an adhesive only to the peripheral part (for example, about 5 mm) of one side or both sides. Moreover, a conventionally well-known material and method can be used for an adhesive, a heat seal, etc. when manufacturing the heat generating body of this invention.

  In the heating element of the present invention, when an adhesive is used, the surface of the adhesive layer is covered with a release sheet when not used. Any material can be used for the release sheet as long as it is conventionally used for a sheet for covering a pressure-sensitive adhesive layer of a heating element, that is, a release sheet.

  The heating element of the present invention (however, in the case of using an adhesive, remains covered with a release sheet) is stored in an outer bag. The outer bag is made of a moisture-proof and air-impermeable material. Since the outer bag is non-breathable, the heating element cannot be contacted with air (oxygen) and therefore does not undergo a chemical reaction and is stored without generating heat. When the outer bag is opened, air (oxygen) passes through the breathable sheet and reaches the exothermic composition, thereby starting a chemical reaction and releasing reaction heat. A typical example of the outer bag material is a laminate of an aluminum thin layer and a polymer film. The heating element of the present invention is usually stored sealed in a bag that is substantially impermeable to oxygen until use after production.

The heating element of the present invention can be used as a heating tool such as a warmer or a heating pad as it is or in combination with other components. For example, it can be applied directly on the skin or applied on the cloth of clothes such as underwear, but when applied from the top of the cloth, the effect of the heating element or heating tool of the present invention can be obtained more clearly. The thickness of the fabric (the total thickness when two or more sheets overlap) is preferably 3 mm or less, and more preferably 2 mm or less.
Such a heating device can be applied to any part of the body. Particularly useful is a heating tool in which a joint part of a limb or the like is a combination of a supporter, particularly a joint supporter such as a knee, and the heating element of the present invention. The supporter used for such a heating tool is provided with a part where the holding member becomes two or more layers by folding it at least twice or making a pocket, and the heating element of the present invention is inserted between the layers. it can. In this way, when using it as a heating tool with a heating element inserted between cloths, etc., if you want to change the temperature, you can experience different heating temperatures by changing the front and back surfaces of the heating element once inserted Become. In particular, since two sensory temperatures can be selected, a heating tool or the like to be inserted into a joint supporter such as a knee is suitable.
The material of the supporter may be any known material, but the thickness of the portion between the heating element of the present invention and the skin is preferably 3 mm or less as described above, preferably 2 mm. More preferably, it is as follows.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

(Production of exothermic composition)
Iron powder 55.0 g, activated carbon 7.0 g, NaCl 2.0 g, water 29.9 g, “Sunfresh ST-571” (manufactured by Sanyo Chemical Co., Ltd., water-absorbing resin) 3.0 g, vermiculite 3.1 g at room temperature The composition was prepared by stirring and mixing for a minute. This composition was used in the production of each heating element in the following examples and comparative examples.

Example 1
A heating element (70 mm × 95 mm) of the present invention was produced as follows.
Polyester nonwoven fabric 7830 (a porous film made by stretching a film mainly composed of an olefin resin and an inorganic filler) made of polyethylene porous film “Kojin TSF-EU” (manufactured by Kojin Co., Ltd.) Breathable sheet A (air permeability: 7,000 seconds / 100 cc, JIS P-8117) laminated with polyester spunlace, manufactured by Shinwa Co., Ltd., weight per unit area: 30 g / m ² ), and the same polyethylene porous film “ Breathable sheet B (air permeability: 30,000 seconds / 100 cc, JIS P) obtained by laminating the same polyester nonwoven fabric 7830 (made by Shinwa Co., Ltd., basis weight: 30 g / m) to “Kohjin TSF-EU” (manufactured by Kojin Co., Ltd.) -8117) with the polyethylene surfaces facing each other and heat-sealing the peripheral edge leaving a part. The flat bag for containing an exothermic composition was prepared. The air permeability of the air permeable sheets A and B was adjusted by changing the coating pattern of the adhesive during lamination. The bag was filled with the exothermic composition (13.5 g), and the opening was heat sealed to produce a heating element I of the present invention.

(Examples 2 to 13, Comparative Examples 1 to 6)
In Example 1, except that the air permeabilities of the sheets A and B were changed to those in Table 1, Examples 2 to 13 (heating elements II to XIII) and Comparative examples 1 to 6 (heating) were performed in the same manner as in Example 1. The heating elements of the bodies XIV to XIX) were produced.

  About each said heat generating body, the measurement by said hot-plate surface method and the practical test (1) and (2) described below were performed. In addition, use apparatus etc. use what was illustrated above, and as a windbreak case, the heat insulation case made from acrylics (Acrylic board thickness 5mm, dimension width 650x length 450x height 300mm, a top plate removal type, Downward open square tube shape, joint bonding with aluminum fittings with screws, top plate bonding part uses sponge packing, circular holes with a diameter of 10 mm on one side, circular holes with a diameter of 10 mm on one side, 15 mm x on the other side Each having a 20 mm square hole).

<Field test (1)>
The following tests were conducted to see how it would actually be used by humans and in motion. In this case, the sensor is placed between the cloths and is not directly in contact with the skin, but this is intended to reduce the influence of the movement of the blood flow of the human body depending on the person.
Wear a supporter folded in the knee of the subject (double supporter: a normal supporter folded in half) and put a heating element in the pocket between the double, and the heating element and the cloth on the skin side A sensor (side temperature sensor; ST-22E-003, manufactured by Anritsu Keiki Co., Ltd.) is attached between the two, and the temperature is measured with a compact thermologger (AM-8000E (TYPE E: -200 to 800 ° C); Adachi Keiki Co., Ltd.). Recorded. The subject had a daily life.

<Field test (2)>
In order to see how it feels sensibly when tested on the human body, the following test was performed on 30 subjects.
As in the field test (1), a heating element was placed in a double supporter and worn for 3 hours with the A side facing the air side. Next, the B side of the heating element was newly worn for 3 hours with the air side. The sensory temperature was evaluated according to the following criteria.
(A) A and B clearly felt the difference in temperature on the skin side, and both temperatures were pleasant temperatures.
(B) A difference in temperature on the skin side between A and B was clearly felt, but either temperature was too hot and blistered or too warm.
(C) A and B felt a slight difference in temperature on the skin side, and both temperatures were comfortable.
(D) Although A and B felt a slight difference in the temperature on the skin side, either temperature was too hot and blistered or too warm.
(E) The temperature difference on the skin side between A and B was unknown.

  The results are shown in Table 1. For the field test (2), the number of people evaluated as corresponding to each was listed. From Table 1, if the average temperature difference according to the hot plate method is 2.0 ° C. or more, the average temperature difference is 2.0 ° C. or more in the practical test (1), and the experience of the subject in the practical test (2) Even with this method, the temperature difference was clearly felt. Based on these results, in order for the human body to clearly feel the temperature difference, it was first necessary that the average temperature difference by the hot platen method be 2.0 ° C. or higher.

Based on the data in Table 1, the air permeability a was plotted on the horizontal axis and the air permeability b was plotted on the vertical axis. The results are shown in FIG.
In Fig. 1, (i) The temperature difference is 2.0 ° C or more with the hot plate surface method, and the direction of the surface can be changed to feel the heat generation temperature difference. (Ii) The average heat generation of the hot plate surface method and the field test (1) Especially as a heating element having a temperature of 48.0 ° C. or less and no blistering, and (iii) an average heating temperature in the same manner as in the hot plate method and field test (1), that is, a heating tool. A preferable heating element is “◯”, and (i) a temperature difference is less than 2.0 ° C. by the hot plate method, and “X” is the one that cannot change the direction of the surface to experience the heating temperature difference, and (ii) to (iii) The heating element that does not satisfy any of the above) was designated as “Δ”. These are due to the idea that the heating temperature is preferable as a heating tool both in the stationary state of the hot plate method and in the moving state of the practical test (1). It was possible to enclose it with three lines so as to include the gathering area where ○ was gathered. The wire connected ○ 's as a critical line.

Each straight line (I) is a straight line connecting (8,500, 20,000) and (20,000, 43,000) for (a, b) and (7) for the second (II) (7). , 30,000, 30,000) and (7,000, 50,000), and the third (III) connects (20,000, 43,000) and (10,000, 70,000). It is a straight line.
The formula of each straight line is b-2a = 3,000, a = 7,000, b = -2.7a + 97,000. That is, the double-sided air-permeable heating element having the preferable air permeability a and b of the present invention is in a region surrounded by these three lines, and a ≧ 7,000 (formula-1), b-2a ≧ 3 , 2,000 (formula-2), b ≦ −2.7a + 97,000 (formula-3).

  Moreover, it carried out similarly to Example 1, produced the comparative examples 7-10 which comprised both surfaces with the air permeable sheet of the same air permeability, and measured with the hot-plate surface method. The results are listed in Table 2 together with the corresponding results in Table 1.

  From this result, the difference between the average surface temperature and the maximum temperature tends to be smaller in the breathable heating element of the present invention that is different in both sides than the double-sided breathable heating element of the same permeability, and can be used comfortably. I understand that.

FIG. 1 is a diagram showing the relationship between the air permeability of sheets A and B in the heating element of the present invention.

The present inventors have found that the above-mentioned object can be easily achieved by configuring both surfaces of a heating element with a combination of breathable sheets satisfying specific conditions, and have completed the present invention.
That is, according to the present invention,
[1] at least in part one is highly air-permeable sheet A of each surface other in the partition without flat bag inside made of sheet having air permeability is low breathable sheet B, and the presence of air the exothermic composition that generates heat a heat generating element formed by sealing state, and are difference 2.0 ° C. above the average surface temperature of the both surfaces were measured by the following methods, selecting different temperatures by changing the surface orientation heating element and can be characterized by Rukoto:
Measurement of surface temperature by hot plate method: A cloth having an average thickness of 550 ± 30 μm and an average basis weight of 185 ± 10 g / m ² is laid on a hot plate surface maintained at a temperature of 30 ± 1 ° C., and heat is generated thereon. A body is placed to generate heat, and the surface temperature of the heating element on the board surface side is measured by a temperature sensor installed between the cloth and the board surface.
Average surface temperature calculation method: As a result of the measurement by the hot plate surface method, the average surface temperature is calculated by averaging the temperatures in a period of 38.0 ° C. or higher ;
[2 ] When the breathability of the breathable sheets A and B by the Gurley method (JIS-P8117) is a and b (seconds / 100 cc), respectively,
b-2a ≧ 3,000 (Formula-1)
The heating element according to [ 1 ], wherein
[ 3 ] Breathability a and b of the breathable sheets A and B according to the Gurley method (JIS-P8117) are:
a ≧ 7,000 (Formula-2)
And b + 2.7a ≦ 97,000 (Formula-3)
The heating element according to [ 1 ] or [ 2 ], wherein
[ 4 ] The heating element according to any one of [1] to [ 3 ], wherein the average surface temperature is 38.0 to 48.0 ° C. for each of both surfaces;
[ 5 ] A heating tool including the heating element according to any one of [1] to [ 4 ] as a constituent element;
[ 6 ] The heating device according to [ 5 ], comprising at least two layers of holding members, and comprising a combination of a supporter for sandwiching and using the heating element between the holding members and the heating element ;
[ 7 ] The heating tool according to [ 6 ], wherein the supporter is for knees;
[ 8 ] A supporter for mounting the heating element according to any one of [1] to [ 4 ], comprising at least two layers of holding members, wherein the heating element is disposed between the holding members. Supporters that can be sandwiched,
Is provided.

The temperature difference between both surfaces can be created by placing a high-temperature exothermic exothermic composition and low temperature exothermic exothermic composition to each of both sides in the interior of the flat bag.
Also, the temperature difference between both sides, to as exemplified breathable control above, the selection of the exothermic composition initially may be realized by combining viewed any means.

The present inventors have found that the above-mentioned object can be easily achieved by configuring both surfaces of a heating element with a combination of breathable sheets satisfying specific conditions, and have completed the present invention.
That is, according to the present invention,
[1] At least a part of each surface is made of a breathable sheet, one of which is a highly breathable sheet A and the other is a low breathable sheet B. A heating element that encloses a heat-generating composition that generates heat, and in which a flat bag is depressurized during heat generation,
When the air permeability according to the Gurley method (JIS-P8117) of the breathable sheets A and B is a and b (seconds / 100 cc), respectively,
b-2a ≧ 3,000 (Formula-1)
Meeting, and
The heating element itself can exhibit two temperatures, and the difference between the average surface temperatures of both sides of the heating element itself measured by the following method is 2.0 ° C. or more. That you can choose ,
Heating element characterized by:
Measurement of surface temperature by hot plate method: A cloth having an average thickness of 550 ± 30 μm and an average weight per unit area of 185 ± 10 g / m ² is laid on a hot plate held at 30 ± 1 ° C., and heat is generated thereon. A body is placed to generate heat, and the surface temperature of the heating element on the board surface side is measured by a temperature sensor installed between the cloth and the board surface.
Average surface temperature calculation method: As a result of the measurement by the hot plate method, the average surface temperature is calculated by averaging the temperatures in a period of 38.0 ° C. or higher;
[2] before Symbol breathable sheet A and the Gurley method B (JIS-P8117) according to the air permeability and a and b are,
a ≧ 7,000 (Formula-2)
as well as
b + 2.7a ≦ 97,000 (Formula-3)
The heating element according to [1], wherein
[3] before Symbol average surface temperature is from 38.0 to 48.0 ° C. For each of both sides, the [1] or [1] Symbol mounting of the heating element;
[ 4 ] A heating tool including the heating element according to [1] to [ 3 ] as a constituent element;
[ 5 ] The heating device according to [ 3 ], comprising at least two layers of a holding member, and comprising a combination of the support and the heating element for sandwiching and using the heating element between the holding members. ;
[ 6 ] The heating device according to [ 4 ] above, wherein the supporter is for knees;
[7] the [1] to [3] A supporter for mounting a heat-generating body according, has a holding member for at least two layers, supporters may sandwich the heating element between the layers of the retaining member,
Is provided.

The heating element of the present invention has the following effects.
(1) Since both surfaces of the heating element itself generate heat at different temperatures, one of the two temperatures can be easily selected and used according to the user's preference by simply changing the surface facing the skin.
(2) During use, the temperature to be freely selected can be changed any number of times from the low temperature side to the high temperature side or from the high temperature side to the low temperature side.
(3) The heat generation is more stable and the difference between the maximum heat generation temperature and the average heat generation temperature tends to be smaller than that of a known heat generation element such as a heat generation element having the same air permeability on both sides and air permeability on both sides, and can be used comfortably. .
(4) Since wet heat is transmitted to the skin side, drying of the skin especially in winter is suppressed, and itching by a supporter and the like is prevented, which is good for health. In addition, the conventional heating element dissipates water vapor (wet heat) together with heat from the holes on the ventilation surface, but the air side is normally the ventilation surface, whereas the heating element of the present invention is breathable on both sides, Moist heat is also dissipated from the ventilation surface on the skin side and hits the skin. Moist heat replenishes the skin and warms it to the deep part of the body with a soft heat feeling at an appropriate temperature, which is good for your health.
(5) During use and after completion of heat generation, little or no heat generation composition is cured, and there is little discomfort.

Claims (9)

A heating element obtained by encapsulating a heat generating composition that generates heat in the presence of air in a flat bag made of a sheet having air permeability at least a part of each surface, the average of both surfaces measured by the following method A heating element characterized in that the difference in surface temperature is 2.0 ° C. or more:
Measurement of surface temperature by hot plate method: A cloth having an average thickness of 550 ± 30 μm and an average basis weight of 185 ± 10 g / m ² is laid on a hot plate surface maintained at a temperature of 30 ± 1 ° C., and heat is generated thereon. A body is placed to generate heat, and the surface temperature of the heating element on the board surface side is measured by a temperature sensor installed between the cloth and the board surface.
Average surface temperature calculation method: As a result of measurement by the hot plate method, the average surface temperature is calculated by averaging temperatures in a period of 38.0 ° C. or higher.   The heating element according to claim 1, wherein both sides of the flat bag are constituted by a highly breathable sheet A and the other by a low breathable sheet B, respectively. When the air permeability according to the Gurley method (JIS-P8117) of the breathable sheets A and B is a and b (seconds / 100 cc), respectively,
b-2a ≧ 3,000 (Formula-1)
The heating element according to claim 2, wherein: Breathability a and b by the Gurley method (JIS-P8117) of the breathable sheets A and B are:
a ≧ 7,000 (Formula-2)
And b + 2.7a ≦ 97,000 (Formula-3)
The heating element according to claim 2 or 3, wherein   The heating element according to any one of claims 1 to 4, wherein the average surface temperature is 38.0 to 48.0 ° C for each of both surfaces.   The heating tool which contains the heat generating body of any one of the said Claims 1-5 as a component.   The heating tool according to claim 6, comprising at least two layers of holding members, and comprising a combination of a supporter for use by sandwiching the heating element between layers of the holding member and the heating element.   The heating tool according to claim 7, wherein the supporter is for knees.   A supporter for mounting the heating element according to any one of claims 1 to 5, comprising at least two layers of holding members and capable of sandwiching the heating element between layers of the holding members.

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