JP2002336290A - Fluid exothermic composition and heating element using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid exothermic composition and a heating element using it which is layered and sealed in a wrapping material for forming the heating element and is capable of preventing a loss of a heating material in production and of easily producing the heating element in an optional shape with good operability by being controlled with fluidity, and that capable of distributing and maintaining the fluid exothermic composition inside the wrapping material with a uniform thickness without applying any excessive load to an extrusion pump and the like in a coater, and especially, capable of performing complicated temperature control based on a continuous void formed inside the exothermic composition by constituting its barrier water contents to move to the wrapping material and/or a water absorbing sheet in the wrapping material after it is layered and sealed in the wrapping material. SOLUTION: This exothermic composition layered and sealed inside the wrapping material to form the heating element is controlled with fluidity and used for the heating element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flowable heat-generating composition for forming a heat-generating body by being laminated and sealed in a packaging material, and a heat-generating body using the same. In addition to being able to easily produce a heating element of any shape, the flowable heating composition can be distributed and maintained in a uniform thickness in the packaging material. By transferring the components to the packaging material and / or the water-absorbing sheet provided on the packaging material, and by forming continuous voids inside the fluid heat-generating composition, the heat-generating substance during the production is reduced. The present invention relates to a fluid exothermic composition capable of preventing loss and complicated temperature control, and a heating element using the composition.

[0002]

2. Description of the Related Art In recent years, as a so-called disposable color rim,
Heat generation in which a powdered heat-generating composition is enclosed in a flat packaging material composed of a film-like or sheet-like base material having air permeability or non-air permeability, and a film-like or sheet-like covering material having air permeability. The body is widely spread and used.

[0003] When the exothermic composition is formed in a powder form as described above, the exothermic composition in a powder form is formulated in an optimal state in which an exothermic reaction, that is, an oxidation reaction, is easily generated. Since it is a porous body, it has a large surface area and extremely good contact with air, and an oxidation reaction occurs immediately upon contact with air.

[0004] Therefore, during the production, during the mixing of the exothermic composition at an appropriate compounding ratio or until the exothermic composition is manufactured and the obtained heating element is sealed in a non-breathable packaging material. In the meantime, an oxidation reaction with air, that is, an exothermic reaction occurs,
In particular, there is a problem in the production of a thin sheet-shaped heating element, such as loss of a heating substance in the heating composition and deterioration of the quality of the heating composition.

[0005] In addition, the disposable body warmers and heating tools filled with the powdered exothermic composition currently on the market are prohibited from being used while sleeping because of the danger of low-temperature burns. If the bedding is used in a good state of bedding, heat is accumulated and the exothermic reaction is further accelerated, resulting in a state of excessive heat generation, a remarkable temperature rise exceeding a predetermined heat generation temperature, and a low-temperature burn may occur.

[0006] In particular, in the case of a heating element used in a shoe, the air supply is greatly reduced in the conventional method because it is used in the shoe. It is designed to have a moderate temperature while wearing shoes, so that when the shoes are taken off, the temperature rises rapidly and the duration is extremely short. For this reason, this type of heating element is prohibited from being used outside of shoes. In addition, the temperature varies depending on the type of footwear, and there have been problems such as the temperature rising excessively and not heating.

[0007] A thin (sheet-like) heating element of the pasting type, which is currently the mainstream, is one in which a powdery heat-generating composition is filled in a packaging material and then compressed into a sheet by roll rolling or the like. Therefore, variations in thickness in the manufacturing process occur,
The heating element cannot be formed into a uniform sheet, and the heat-generating composition may move within the packaging material during transportation or use, resulting in unevenness or a sense of incongruity, and a variation in the temperature distribution resulting in low temperatures. There has also been a problem that skin disorders such as burns may occur.

In addition, when a needle hole is used in the breathable film, there is a problem that the powder moves freely in the bag and does not form a sheet, and the powder jumps out of the hole and stains clothes, shoes and socks. If a porous film is used as the ventilating film, it becomes a pseudo sheet-like shape, but the thickness is not uniform, and the permeability of the porous film varies greatly between lots and within lots. Width is ± 30%
At present, the heat generation temperature is largely affected, so that the standard temperature range of the product cannot be narrowed at present. In addition, when used for shoes, the temperature rises when the shoes are taken off, the water vapor pressure increases, the heating element swells, and there is a risk of explosion when putting on the feet.

In order to solve these various problems, the present inventors have suppressed the exothermic reaction of the exothermic composition,
Loss of the exothermic composition due to exothermic reaction at the time of production, deterioration of exothermic composition quality and various adverse effects associated with solidification of the exothermic composition can be prevented, and an ultra-thin heating element can be manufactured at high speed. In addition to preventing the heat-generating composition from moving and leaning by uniformly distributing and fixing the heat-generating composition in the packaging material, the inventors have intensively studied a heating element that minimizes excessive heat generation reaction of the heat-generating composition.

As a result, the inventor of the present invention has proposed that screen-printing, gravure printing, and the like can be achieved by using a “viscous heat-generating composition”, that is, a heat-generating composition whose viscosity is controlled by viscosity, instead of the powder heat-generating composition. It is extremely easy to laminate on a film or sheet-like base material by coating or coating, etc., and it is possible to manufacture an ultra-thin heating element at high speed. In addition, per unit area when laminating a heating composition in a packaging material In this viscous heat-generating composition, the moisture in the viscous heat-generating composition or the water in the free water or the gel containing the moisture can be distributed to the air-blocking layer (hereinafter referred to as barrier water). ), So that the contact with air is remarkably reduced as compared with the powdered heat-generating composition. Therefore, the exothermic reaction during the manufacturing process can be stopped, and the loss of heat-generating substances such as metal powder can be reduced. It found that can bets have filed a patent application (JP-A-9-75388).

However, while this viscous exothermic composition has such excellent advantages, it has a water-absorbing polymer and / or
Alternatively, the exothermic composition becomes denser depending on the type and amount of the thickener and the amount of water, and the volume of the exothermic composition is further reduced due to the exothermic reaction. Insufficient air supply due to incomplete formation,
There is a problem that heat generation efficiency is reduced.

Therefore, the present inventor has proposed that by adding aggregate particles to the viscous exothermic composition, the aggregate particles can prevent the volume change due to the exothermic reaction and gradually enlarge the air supply passage. It was found that the contact between the heat-generating composition inside the heating element and the air was extremely good, and that the exothermic reaction continued for a long time, and a patent application was filed.
192329).

[0013]

However, Japanese Patent Application Laid-Open No. 9-75388 or Japanese Patent Application Laid-Open No. 10-192329
In the case where a heating element is manufactured using the “viscous heating composition” disclosed in Japanese Patent Application Publication No. H11-27139, the heating composition is supplied to a head or a coater in a laminating step at the time of manufacturing, and the base is supplied from the head. When extruded on wood, the quantitativeness varies depending on the type and amount of aggregates, and water flows out and separates from the heat-generating composition, resulting in an uneven mixing ratio and a variation in performance. And a heavy load is applied to the pump, and the occurrence of problems such as heat generation and stop of the motor has been reported in many cases.

Although this problem was thought to be due to the "viscosity" of the exothermic composition, the same viscosity value (viscosity)
However, this problem may or may not occur even with a heating element having the above, and its cause has not been elucidated until now.

The present inventor has examined and investigated the cause of this problem. The problem was not caused by the "viscosity" of the exothermic composition, but was caused by the "fluidity" of the exothermic composition. It was confirmed that it was.

That is, if the exothermic composition has poor fluidity, an extremely large force is required when the exothermic composition is supplied to a head or a coater and extruded from the head into a sheet.
For this reason, a load is imposed on the extrusion motor, and the motor generates heat or stops, and as a result, moisture is squeezed out of the exothermic composition, resulting in variation in quantitativeness,
This also affected the heat generation performance of the manufactured heating element.

However, up to the present, the perception of this fluidity is considered to be proportional to or equivalent to the viscosity of the exothermic composition, and the viscous exothermic composition has fluidity, Therefore, it was recognized that if the viscosity was controlled, the fluidity would be a value corresponding to it.

However, the present inventor has examined and examined several exothermic compositions in this regard.
The above-mentioned idea is a completely wrong idea, that is, viscosity and fluidity are neglected, and low viscosity does not always mean good fluidity, and conversely, fluidity is high even if viscosity is high. Some have good properties, and it has been found that the fluidity of the exothermic composition cannot be controlled only by controlling the viscosity.

Accordingly, the present inventor has solved the above-mentioned problems by controlling the exothermic composition by the fluidity, making it possible to use printing technology and coating technology in the manufacturing process, and very simply and accurately quantitatively. (Measurement) and the quality of the heating element can be improved.

Further, by controlling the exothermic composition by fluidity, the exothermic composition can be pipe-transported by a pump or the like, and can be directly packaged from the raw material tank to the laminating step without contact with air. They also learned that they can be laminated on materials.

Furthermore, the exothermic composition controlled by the fluidity contains a large amount of water, and the water becomes a barrier water with respect to the air. It was also found that there was no loss of exothermic substance due to heat generation at the time, and that deterioration in quality could be prevented.

After laminating and enclosing the exothermic composition controlled by the fluidity in the packaging material, the barrier moisture in the exothermic composition is transferred to the packaging material and / or the water-absorbing sheet provided on the packaging material. The inventor has also obtained the knowledge that, as a result of continuous movement inside the exothermic composition, the exothermic reaction inside the exothermic composition becomes smoother as a result of forming the movable exothermic composition.

When the fluidity is low, there is a problem that the film may be stretched or cut when laminated on a stretchable wrapping material or a weak water-absorbent sheet. We have also learned that these problems can be avoided.

In general, when the aggregate is mixed, the fluidity is reduced, so that it is necessary to increase the thickener and the water content. However, it has been found that such a configuration reduces the exothermic reactivity and does not solve the problem. Also got.

Therefore, there has been a demand for an aggregate which does not decrease the flowability without increasing the amount of the thickener and the moisture even when the aggregate is blended. By the addition of the hydrophobic aggregate, the movement of water in the exothermic composition is accelerated, a continuous void can be formed inside the exothermic composition in a short time, the exothermic reaction efficiency is remarkably improved, and furthermore, the oxidized composition is oxidized. As a result of being able to prevent the iron powders from being bonded to each other, it has been found that the flexibility of the heating element during use or after use is not impaired, and the flexibility and usability can be improved. .

The present invention has been completed based on the above-mentioned technical knowledge, that is, in a heat-generating composition for forming a heat-generating body by being laminated and sealed in a packaging material, the heat-generating composition has a fluidity. In addition, heat loss during production can be prevented, heat resistance is extremely good, heating elements of any shape can be easily manufactured, and excessive load is applied to pumps for extruding coaters. Without giving
The exothermic composition can be distributed and maintained in a uniform thickness in the packaging material, and in particular, after the exothermic composition is laminated and sealed in the packaging material, the moisture for the barrier in the exothermic composition is reduced. By moving the wrapping material and / or the water-absorbing sheet provided on the wrapping material, continuous voids are formed inside the heat-generating composition, and a fluid heat generation that enables complicated temperature control is possible. An object of the present invention is to provide a composition and a heating element using the composition.

[0027]

Means for Solving the Problems The fluid exothermic composition according to the present invention (hereinafter referred to as "the present invention") is laminated and enclosed in a packaging material to form a heating element in order to achieve the above object. An exothermic composition for forming, characterized in that the exothermic composition is controlled by fluidity.

The heating element according to the present invention (hereinafter referred to as "the heating element of the present invention") is obtained by laminating the above-mentioned product of the present invention in a packaging material having air permeability at least in part. Characterized by being enclosed. Hereinafter, the present invention and the heating element of the present invention will be described in detail in order.

The present invention is characterized in that it is not a powdery exothermic composition as in the prior art but a fluid exothermic composition controlled by fluidity.

The product of the present invention is not particularly limited as long as it is composed of a component which reacts with oxygen in the air to cause an exothermic reaction and exhibits a fluidity.

Specifically, for example, it can be obtained by adjusting the mixing ratio of water and other components in each component constituting the present invention.

The fluid exothermic composition of the present invention is a exothermic composition controlled by fluidity, and at the present stage, a texture analyzer (S, UK) described later.
Table Micro Systems, Model T
Although it is preferable to measure and manage the value of the fluidity by a measuring method using X-XT2i) or the like, other methods or devices for measuring the fluidity will be established in the future, and the measured value and the aforementioned If a certain correlation can be obtained with the measurement value obtained by the measurement method using the texture analyzer, it is a natural idea in the technical idea of the present invention to measure and manage the fluidity using the method. That is the matter.

The present invention has the following advantages as a result of having such a configuration.

That is, since the material of the present invention has fluidity, the material of the present invention is supplied to a head or a coater, and is pressed onto the stencil or intaglio from the head and scraped by a doctor to measure the volume quickly with a small force. Extruded, it becomes possible to scrape off the excess heat-generating composition smoothly, so that it is difficult for the motor for extrusion to take a load, and the motor does not generate heat or stop, for example, transfer,
Uses well-known transfer / printing techniques such as thick coating printing, gravure printing, offset printing, screen printing, spraying, or coating and coating with a head coater, roller, applicator, etc. In addition to being able to manufacture ultra-thin heating elements at high speed, it is very easy and accurate to measure (measure)
As a result, the exothermic composition can be evenly distributed in the packaging material.

Further, by controlling the exothermic composition by fluidity, the exothermic composition can be pipe-transported by a pump or the like, and can be directly packaged from the raw material tank to the laminating step without contact with air. It can be laminated on the material.

Further, in the exothermic composition controlled by the fluidity, the exothermic substance is covered with moisture, and the moisture acts as a barrier to air. Therefore, there is no loss of exothermic substance due to heat generation in the above, and deterioration of quality can be prevented.

In the present invention, there may be mentioned those having a heat generating substance, a carbon component and / or a metal chloride and water as constituent components and having fluidity as a whole. In this case, if necessary, a water-absorbing polymer and / or a thickener may be added.

As a mixing device for these components, a conventional one may be used. However, if the mixing is carried out for a long time in the form of a powder having a large amount of contact with air with a low content of all components or water, heat is generated, Since water evaporates and the fluidity changes, a kneading device that can be formed into a viscous material that exhibits fluidity in a short time is desirable. In order to suppress heat generation as much as possible, it is desirable to add the heat-generating substance after the components other than the heat-generating substance are made into a viscous body. It is further desirable to reduce the load on the device.

The exothermic composition having fluidity in the present invention is not particularly limited as long as the exothermic composition has fluidity and the required temperature characteristics can be obtained. Specifically, for example, 0.1 to 10 parts by weight of a water-absorbing polymer and / or 0.1 to 10 parts by weight of a thickener, and 1.5 to 20 parts by weight of a carbon component and / or 100 parts by weight of a heating substance. Metal chloride is in the range of 1 to 15 parts by weight, and further, with respect to 100 parts by weight of the exothermic substance, 0.5 to 10 parts by weight of an inorganic or organic water retention agent and 0.1 to 0.1 part by weight of a pH adjuster.
It is preferable that at least one selected from 5 parts by weight is blended. In particular, the mixture is formed to have fluidity by adding water to the mixture. In this case, a predetermined amount of the metal chloride is dissolved or dispersed in water, and this is mixed with the water-absorbing polymer and / or the thickener and the carbon component and / or
Alternatively, it may be formed so as to have fluidity as a whole in addition to a mixture composed of a metal chloride.

Examples of the water-absorbing polymer include those described in Japanese Patent Application Laid-Open No. H10-155827. Specifically, for example, KI Gel 201-K manufactured by Kuraray Co., Ltd. , KI gel 20
1-F2, Sanfresh S manufactured by Sanyo Chemical Industries, Ltd.
T-500MPS and the like.

In the present invention, examples of the thickener include substances which absorb water or an aqueous solution of a metal chloride to increase the consistency or impart thixotropic properties. Examples of the thickener include bentonite and activated clay. , Stearates,
Polyacrylates such as sodium polyacrylate, gelatin, polyethylene oxide, polyvinyl alcohol,
Polyvinylpyrrolidone, gum arabic, tragacanth gum, locust bean gum, guar gum, gum arabic, alginates such as sodium alginate, pectin, carboxyvinyl borimer, dextrin, starch-based water absorbing agents such as pregelatinized starch, starch for processing, carrageenan, agar Polysaccharide thickeners such as CMC, ethyl acetate, hydroxyethyl cellulose, cellulose derivative thickeners such as methylcellulose or hydroxypropylcellulose, water-soluble cellulose ethers, N-vinylacetamide, acrylic emulsions, urethane emulsions, etc. One or a mixture of two or more selected ones may be mentioned. These thickeners mainly absorb water or an aqueous solution of a metal chloride and increase the fluidity.

The exothermic substance used in the present invention, the carbon component,
Examples of the metal chloride include, for example, JP-A-10-15582
No. 7 is described as an example.

Examples of the pH adjuster include commonly used pH adjusters such as calcium hydroxide.

Although the present invention is controlled by fluidity, the fluid exothermic composition may be a viscous fluid or a plastic fluid, but a certain amount of force is applied. A fluid heat-generating composition that exhibits plastic fluidity that does not cause deformation is desirable because uniform transfer is easy. In other words, the flowable heat-generating composition exhibiting viscous flowability is not preferable because a proportional change occurs immediately in response to an applied external force, and the transfer amount is relatively likely to vary.

The product of the present invention is controlled by fluidity as described above.
It may be appropriately determined according to the printing method used in the manufacturing process, the performance of the coating head, coater, or pump for pushing out. At this stage, at the temperature of 20 ° C., the texture analyzer (Stab, UK) is used.
Model TX-X, manufactured by le Micro Systems
The measured value by the measuring method using T2i) or the like is 0.5 to 2
It is desirable to be in the range of 0.0 kg / cm ² .

The fluidity of the exothermic composition is 0.5 kg
/ When cm ² and less than too small, the water can not hold the uniformity of the components by extremely excessive since precipitation, also may become poor extremely excessive when reactivity thickeners, transfer amount of the other ingredients Is insufficient, the heating time is short, the exothermic composition oozes out of a predetermined area on the substrate after the transfer, and the sagging easily occurs, and it is necessary to absorb a large amount of moisture into the substrate after the transfer. However, it is not preferable to use a substrate having a special structure or to complicate the structure of the heating element.
If it exceeds kg / cm ² , the fluidity becomes so low that the exothermic composition is supplied to a head or a coater, and when extruding from the head onto a substrate, a very large force is required. Since the motor takes a load, the motor generates heat and stops, and the water is squeezed out of the heat-generating composition, which causes variations in quantitativeness and affects the heat-generating performance of the manufactured heating element. Yes,
Further, it is not preferable because pipe transportation by a pump or the like becomes difficult.

Therefore, for these reasons, the temperature 2
At 0 ° C., 1.0 to 10.
A fluidity range of 0 kg / cm ² is preferred,
A flowability range of ７7.0 kg / cm ² is particularly preferred.

The measured values were obtained using a texture analyzer (Stable MicroSystems, UK).
It was measured by a tubing test using Model TX-XT2i) manufactured by MS). Software (Windows (registered trademark) version): SM
S Texture Expert Computer: PC300PL manufactured by IBM was used. Method of tubing test Measure about 200 g of the fluid exothermic composition in a cylinder with a balance, level the surface to some extent with a spoon, and take into account the degree of nailing of the fluid exothermic composition and the gap between the fluid exothermic compositions. First, the piston is manually lowered from the top of the cylinder, a constant load (1 kg) is applied, measurement is started after a part of the fluid exothermic composition comes out from the bottom hole of the cylinder, and the measurement is started at a constant speed (1 Kg). (0.0 mm / sec), and the load applied to the piston when the fluid exothermic composition flows out from the bottom hole was measured with the texture analyzer at a load of 10.0 mm. The smaller this value is, the higher the fluidity is. Cylinder shape Inner diameter 5 with 10mm round hole at bottom
0 mm cylinder Piston shape Disc-shaped plate with outer diameter 48 mm Thickness 5 mm The texture analyzer (Stable, UK)
Model TX, manufactured by Micro Systems (SMS)
-The setting conditions of the measurement program of XT2i) were as follows. Test Type: Load measurement by compression Measure Type: Return to start position Pre-test Speed: 1.0 mm / sec Test Speed: 1.0 mm / sec Post-test Speed: 10.0 mm / s
ec Distance: 10.0 mm Probe: Tubing cell (10 mm insert)
HDP / FE Platform: Tubing cell platform Temperature: 20 ° C Trigger: Auto: 500 g PPS: 200

In general, in such an exothermic composition, the fluidity immediately after kneading is the highest, and thereafter the fluidity gradually decreases. , At the time of lamination.

As described above, in the present invention, the mixing ratio of water in the exothermic composition, the water-absorbing polymer and / or
Or, by mixing and adjusting a thickener, it is configured to have a certain fluidity (and viscosity), so that transfer and lamination by printing or coating etc. can be performed without imposing an excessive load on the extrusion motor etc. It is extremely easy to produce an ultra-thin heating element at high speed, and moreover, the water in the free hydrous or the hydrous gel becomes the water for the barrier to form a barrier layer, and the supply of air is reduced. As a result, the exothermic reaction is substantially stopped, so that the exothermic reaction is more stable in the air, and a merit that the exothermic material is lost due to the exothermic reaction during production, the quality of the exothermic composition is reduced, and the solidification of the exothermic composition is further prevented. It is.

When a part or all of the moisture for the barrier is absorbed by the packaging material and / or the water-absorbent sheet described later after the production, the barrier layer is lost, and the heat-generating composition is dense and has a small surface area. As a result, the surface becomes porous and has a large surface area, so that good contact with air is obtained.

However, when the thickness of the heat generating composition layer is large, for example, when the thickness of the heat generating composition is 800 μm
In such cases, the heat-generating substance is pulverized as it loses moisture and is filled in the gaps between the heat-generating substance particles, making it impossible to form a sufficient air supply path to become dense or reduce the volume. As a result, the continuity of the reaction may be insufficient and the reaction efficiency may decrease.

Therefore, in the present invention, in addition to the fact that the exothermic composition has fluidity, after the exothermic composition is laminated and sealed in a packaging material, the water for barrier in the exothermic composition is used. It is preferable that the heat transfer composition be configured such that continuous space is formed inside the heat generating composition by moving the component to the packaging material and / or the water absorbing sheet provided on the packaging material.

That is, by forming a continuous void inside the exothermic composition, a change in volume due to the exothermic reaction is prevented, and the air supply passage is gradually expanded and formed to form an internal exothermic substance. The contact between the exothermic composition and the air becomes extremely good, the exothermic reaction inside the exothermic composition becomes smooth, the exothermic reaction is continued for a long time, and a heating element having good exothermic characteristics can be obtained.

Further, since continuous voids are formed inside the exothermic composition, it is possible to prevent the iron powder oxidized by the exothermic reaction from binding to each other. As a result, the heating element during or after use is used. Thus, the flexibility and the feeling of use can be improved.

As a method of forming continuous voids inside the exothermic composition, for example, a fiber for forming voids is blended in the exothermic composition, and after the exothermic composition is laminated and sealed in a packaging material, A structure in which a continuous void is formed inside the heat-generating composition by moving barrier moisture in the heat-generating composition to the packaging material and / or the water-absorbing sheet provided on the packaging material. Is preferred.

As the fibers for forming the voids, there are disclosed in
Aggregate particles as disclosed in JP-A-192329, for example, activated clay, perlite, silica-alumina powder, silica-magnesia powder, calcined magnesia, kaolin, pumice, zeolite, magnesia powder, precipitated alumina gel, active Alumina, calcium carbonate, silica gel, cristobalite, vermiculite, silica-based porous materials, silicates such as calcium silicate, silica stone, diatomaceous earth, conglomerate such as alumina, conglomerate silicic acid such as mica powder and clay, talc, etc. It is also possible to use, for example, clay-silica, silica powder, activated carbon, charcoal, organic and / or inorganic short fibers, wood powder or pulp powder.

However, the aggregate particles disclosed in JP-A-10-192329 are preferably particles having water absorption and / or water retention, or organic and / or inorganic short fibers.

In Japanese Patent Application Laid-Open No. Hei 10-192329, the reason that aggregate particles having water absorption and / or water retention are preferable is that aggregate particles having water absorption and / or water retention are contained in the heat-generating composition. This is because, when the water or the salt water is retained and the water content in the exothermic composition is insufficient due to the exothermic reaction, it is preferable in that the insufficient water or the salt water is released from the aggregate particles.

Above all, as the aggregate particles in JP-A-10-192329, porous ones are preferable. When the water content is reduced by an exothermic reaction, the porous aggregate particles themselves can supply water and remove air. It is expected to have a role as a supply passage of the same.

However, Japanese Patent Application Laid-Open No. 10-192329
The aggregate particles in the item No. were not selected in consideration of the fluidity of the exothermic composition, and in the present invention, when such aggregate particles having water absorbency were used, the aggregate particles became the exothermic composition In order to absorb the water inside, reduce the fluidity of the exothermic composition and make it difficult to control the fluidity, it is necessary to increase the blending amount of water, and as a result, the initial heat generation becomes slow or iron Problems such as bleeding of water containing ions occur. In particular, when powder of alumina, silica, or the like is used as the aggregate particles, this problem becomes more prominent.

This problem can be solved by using a material having a high water absorption as the packaging material and / or the water absorbing sheet, but this increases the cost and adversely affects the flexibility and the seal strength. Cause to give.

Therefore, in the present invention, it is preferable to use a hydrophobic void-forming fiber as the void-forming fiber for forming continuous voids inside the exothermic composition.

That is, by using a hydrophobic void-forming fiber as the void-forming fiber,
The void-forming fibers maintain good fluidity without absorbing the moisture in the exothermic composition, while, after being laminated and encapsulated in the packaging material, the moisture for the barrier in the exothermic composition is quickly released. At the same time, the void-forming fibers supplement iron powder, activated carbon, and the like, and at the same time, form a so-called three-dimensional network structure, so that continuous voids can be formed.

In this case, the water required for the exothermic reaction is
It has been confirmed that the exothermic composition layer and the packaging material and / or the water-absorbing sheet are separated and held, and that a sufficient amount is sequentially supplied with the exothermic reaction. There is no need to increase the amount of water, the initial fever slows down,
There is no problem such as leaching of water containing iron ions.

In the present invention, the porosity generated in the exothermic composition can be freely controlled by adjusting the blending amount, the fiber length, and the fiber thickness (diameter) of the void forming fiber. In addition, there is an advantage that complicated temperature control becomes possible.

That is, in the present invention, the exothermic composition can be adjusted by adjusting the blending amount of the void-forming fiber or appropriately selecting the fiber length and fiber thickness (diameter) of the void-forming fiber. By combining the network structures formed therein, the porosity can be freely changed, the initial heat generation rate can be improved, and the heat generation time can be maintained for a long time.

That is, in the product of the present invention, the blending amount of the void-forming fiber, the fiber length and the fiber thickness (diameter) are adjusted, and the porosity generated in the heat-generating composition is freely controlled, so that the desired value can be obtained. It can be a heat generating composition according to the characteristics.

Therefore, in the present invention, the blending amount, fiber length and fiber thickness (diameter) of the void-forming fiber are appropriately selected according to the characteristics required for the heat-generating composition. Although not limited, the compounding amount of the general void-forming fiber is in the range of 0.1 to 20% by weight, preferably 1 to 10% by weight of the entire heat-generating composition.
Is preferred, and the fiber length of the void-forming fiber is preferably 3 mm or less, particularly 2 mm
The following are more preferable, those having a thickness of 0.005 to 1.5 mm are more preferable, and those having a finer fiber diameter (diameter), that is, those having a thickness of 500 μm or less are preferable, and those having a thickness of 200 μm or less are preferable. More preferably, it is more preferably 100 μm or less, and particularly preferably 0.1 μm or less.
More preferably from 005 to 50 microns.

If the amount of the void-forming fiber is less than 0.1% by weight in the entire exothermic composition, the amount of the exothermic material in the exothermic composition is too small because the air supply path is insufficiently formed. Contact with air may be poor, while 2
If it exceeds 0% by weight, the absolute amount of the heating substance will be insufficient,
Both are not preferred because they may affect the fluidity of the exothermic composition or make it difficult to secure a required exothermic time.

When the fiber length of the void forming fiber exceeds 3 mm, the fiber direction is aligned with the extrusion direction of the coater when extruding from the coater or scraping with a doctor.
It is not preferable because it is difficult to form a sufficient network structure, it is caught by a doctor, and the lamination surface becomes rough and the lamination amount becomes unstable. Further, the fiber length of the void forming fiber is
When the thickness is less than 0.005 mm, the length is too short, the formation of the network structure is insufficient, and the effect is poor. As a result, contact between the heat generating substance in the heat generating composition and air may be deteriorated, which is not preferable. .

Further, the fiber thickness (diameter) of the void forming fiber
However, if it exceeds 500 microns, it is difficult to efficiently form a network structure and the fluidity is adversely affected. Also, the fiber thickness (diameter) of the void forming fiber is
If the thickness is less than 0.005 micron, the fibers are too thin to block the air inflow path, and as a result, the contact between the heat generating substance in the heat generating composition and the air may deteriorate, which is not preferable.

The blending amount, fiber length and fiber thickness of the void-forming fibers mentioned above are merely general ranges, and not only are the blending amount and fiber length individually adjusted, but also
By adjusting these parameters in a well-balanced manner, more complicated temperature control becomes possible.

Further, by using a mixture of several kinds of void forming fibers having different fiber lengths and fiber thicknesses, more complicated temperature control becomes possible.

The amount of the thickener can be reduced due to the thickening effect of the void-forming fiber of the multi-branched structure having a structure in which the branch is branched from the trunk, particularly as the void-forming fiber. Further, it is preferable from the viewpoint of sagging prevention which is printability.

That is, by using a fiber having a multi-branched structure as the void-forming fiber, the trunk portion and the branch portion can be intertwined in a complicated manner, so that the capability of forming the voids becomes extremely high. Thus, a heat generating composition having a desired porosity can be easily formed without affecting the fluidity of the heat generating composition.

In this case, the thickness (diameter) of the branch portion and the trunk portion of the void forming fiber of the multi-branched structure is appropriately selected according to the characteristics required for the heat-generating composition. Although not limited to, in general, thinner ones are effective, and the trunk preferably has an average diameter of 500 microns or less, and more preferably several microns to 300 microns. Is more preferred, while
Preferably, the branch has an average diameter of 150 microns or less, more preferably 0.005 to 50 microns, and particularly preferably 0.001 to 25 microns.

As the void-forming fibers used in the present invention, known organic and / or inorganic fiber materials consisting of “natural fibers” or “artificial fibers” having the above-mentioned properties can be suitably used. It can be appropriately selected and used according to the characteristics required for the exothermic composition.

Specifically, for example, natural fibers include plant fibers such as cotton, kapok, flax, ramie, hemp, jute, syrup, manila hemp, sisal and coco fiber;
Or silkworm silk, tussah silk, wool, cashmere hair, camel hair,
Examples include animal fibers such as alpaca hair, mohair and rabbit hair, cow hair, horse hair and human hair.

On the other hand, artificial fibers include regenerated fibers such as viscose artificial silk, viscose soup, Bemberg, soybean casein fiber, peanut protein fiber, corn protein fiber and milk casein fiber, polyamide-based fiber, polyamide-based synthetic fiber and the like. Fiber, polyester synthetic fiber,
Synthetic fibers such as polyvinyl alcohol synthetic fibers, polyvinyl chloride synthetic fibers, polyvinylidene chloride synthetic fibers, acrylic synthetic fibers, methacrylic synthetic fibers, polyolefin synthetic fibers, fluorocarbon synthetic fibers or polyurethane synthetic fibers, or And mineral fibers and inorganic fibers such as glass fiber, asbestos (asbestos), carbon fiber, silicon carbide fiber and stainless steel fiber.

In addition, cellulose acetate is converted to cellulose acetate by acetic acid conversion, and this is dissolved in a solvent and spun to produce synthetic acetate fiber,
What is called a so-called semi-synthetic fiber such as chinon produced by copolymerizing a natural substance and a synthetic substance can also be used.

Of course, among these fibers, those having hydrophobicity and those having a multi-branched structure are preferable as the fibers for forming voids in the present invention, as described above. For fibers that do not have hydrophobicity or a multi-branched structure among the fibers, the fibers are subjected to a process such as fibrillation into a multi-branched structure, or subjected to heat treatment or coating to make the fibers hydrophobic. It is a more preferable embodiment to use.

Among the fibers for forming voids in the method of the present invention, from the viewpoints of hydrophobicity, sagging prevention, thickening effect, stability of fluidity, void formation and prevention of component separation, polyolefin-based fibers formed into multibranched fibers are preferred. Is most preferred.

Examples of commercially available polyolefin-based synthetic fibers converted into multibranched fibers include, for example, Chemibest series FD990 and FD78 manufactured by Mitsui Chemicals, Inc.
0, FD380, FDSS-2 and FDSS-5.

Next, the heating element of the present invention will be described in detail, but portions which are the same as those described in the description of the present invention will be omitted to avoid repetition.

The heat generating element of the present invention is characterized in that the present invention is obtained by laminating and enclosing the present invention in a sheet-like packaging material having air permeability at least in part.

That is, the present invention used in the heating element of the present invention includes those described above, and furthermore, the barrier moisture of the present invention is provided on the sheet-like packaging material and / or the packaging material described later. It is constituted so that it may be absorbed by the water absorbing sheet.

As a result, in the heating element of the present invention, part or all of the barrier moisture contained in the present invention, which is laminated and enclosed in the packaging material, is absorbed by the packaging material and continuously formed inside the present material. Voids are formed.

The term "water-absorbing" as used herein means that the material itself does not absorb water as in the case of a synthetic resin packaging material in addition to the material itself having a water absorbing property, but the formed fine pores and fibers Also includes those in which moisture is adsorbed in the gap.

In the heating element of the present invention, when at least one of the base material and the coating material has water absorbency,
As a result of this kind, the heat sealing property of the packaging material is poor, so that the heat sealing of the sealing portion in the peripheral portion of the packaging material becomes weak, so it is necessary to seal with a hot melt adhesive or other adhesive or adhesive. There is.

However, even when the peripheral portion of the heating element is bonded with a hot-melt adhesive or the like, there is a danger that the sealing strength will decrease due to a rise in temperature and that the heating element will be peeled off. Since the material is hydrophilic, and the seal is incomplete and sealability cannot be obtained, problems such as soiling of clothes and skin due to bleeding or seepage of iron ions, etc., and moisture in the heat generating composition In addition, there is a problem that the sealing strength is further reduced due to the absorption of the coating material, and the sealing portion is peeled off.

Therefore, in the heating element of the present invention, in order to enhance the sealing strength of the sealing portion and the sealing performance of the sealing portion, a hydrophobic material is used as the packaging material (base material and coating material).
Laminating a water-absorbing sheet described later in the wrapping material, and using a structure configured to absorb the barrier moisture in the exothermic composition to the water-absorbing sheet, but as a result of the strong bonding of both, there is no delamination, This is preferable because the reliability can be significantly improved.

When the water-absorbing sheet is laminated as described above, the water-absorbing sheet functions as a breakwater for preventing the exothermic composition from seeping out. This makes it possible to form a perforation with an extremely large diameter.

Preferred examples of the substrate and the coating material include:
For example, thermoplastic resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, polyester, polyamide, polyurethane, polyvinyl chloride, polyvinylidene chloride, polystyrene or saponified ethylene-vinyl acetate copolymer, and natural rubber or synthetic rubber In the packaging material, the same type or different types can be used as long as the base material and the coating material can be thermally fused or bonded to each other.

The base material and the covering material used in the heating element of the present invention are air-permeable (porous) or non-air-permeable films or sheets, and are heat-adhesive or heat-fusible. Preferably, a single-layer film or sheet obtained by forming the thermoplastic resin into a film or sheet is also suitably used. Specifically, for example, polyethylene / polyester, polyester nonwoven / polyester or nonwoven / A laminated film or sheet of polyethylene or the like is also preferably used, and since the base material and the covering material can form perforations such as punch holes by laminating a water-absorbing sheet, a porous film or sheet is not necessarily used. There is no need to use it.

The thicknesses of the base material and the coating material vary greatly depending on the application, and are not particularly limited. Specifically, for example, Japanese Patent Application Laid-Open No. H10-155827
Japanese Patent Application Laid-Open No. H10-26095 is mentioned as an example.

As a method for imparting air permeability to the film or sheet made of the non-permeable polymer material, a conventionally known method can be used. Specifically, for example, the film or sheet is stretched when forming the film or sheet. In addition to a method of forming a vent, a method of extracting a specific component from the film or sheet to form a vent, and a method of forming a film and then mechanically forming the vent by punching or fine needle perforation, etc. Thus, a breathable film or sheet can be obtained.

In the case where at least one or a part of the base material and the coating material has air permeability, the air permeability has a great effect on the control of the reaction rate or the heat generation temperature of the exothermic composition. It is preferable to control the air permeability in order to obtain a sufficient thermal effect and prevent low-temperature burns to ensure safety.

In the case of a sheet-like heating element using a conventional powdery heat-generating composition, a stretched porous film is used in order to maintain a sheet state. Therefore, there are problems such as a large variation in the air flow rate, a long time to measure the air flow rate, an expensive measuring device, an expensive film, and a lot of variation between lots and lots. is there.

However, in the heating element of the present invention, since the sheet state can be maintained by using the perforated film, a porous film which is troublesome to manage is not essential.
The use of a perforated film allows quick initial heat generation, facilitates stable temperature control, facilitates the control of heat generation characteristics by the size and arrangement (interval) of perforated holes, and furthermore, generates heat immediately from the holes. Once started, the heat is successively transferred around the holes, the duration can be extended, the overheating during use can be prevented, and the temperature characteristics can be easily controlled, especially by the interval between the holes.

In the present invention, the air permeability varies depending on the application. Specifically, the air permeability is measured by a Gurley type densometer [Model G-B2C, manufactured by Toyo Seiki Seisakusho Co., Ltd.]. 5-50 seconds / m for body
1. For shoes, it is preferably about 0.5 to 5 seconds / ml. or,
In the present invention, the needle diameter of the perforated hole is 0.9 to 2 mm in diameter.
It is preferable to use needles at intervals of 4 to 10 mm.

As described above, in a preferred embodiment of the heating element of the present invention, the moisture for a barrier in the heating composition is absorbed by a gas-permeable water-absorbing sheet covering one or both surfaces of the heating composition. The heat-generating composition is made porous by removing the barrier layer of the heat-generating substance, and is formed so as to have good contact with air.

The water-absorbing sheet is not particularly limited as long as it is formed of a water-absorbing sheet having air permeability and is in contact with the heat-generating composition and absorbs a part of the moisture. Although it is not a thing, specifically, recycled paper,
Paper, cardboard, coated cardboard, liner paper or paper such as pulp non-woven fabric, water-absorbent foam film / sheet (foam such as water-absorbent foam polyurethane), formed of hydrophilic fibers such as rayon or cotton Non-woven fabrics, woven fabrics or knitted fabrics may be mentioned. Of these, paper, cardboard or liner paper is preferably used when priority is given to water absorption and functionality and further economical efficiency. If a soft feeling of the heating element is required, use a nonwoven fabric with a large porosity, or use a hydrophobic nonwoven fabric with cushioning properties.
What is necessary is just to laminate | stack between a base material or a coating material, and the said water absorbing sheet. In particular, when these materials are attached to the inside of the underwear and used, not only is the use time significantly improved,
Extremely good results are obtained, such as the prevention of low-temperature burns.

In the heating element of the present invention, examples of other suitable water-absorbing sheets, their basis weight, water absorption and air permeability are described in, for example, Japanese Patent Application No. 2001-568 filed on Mar. 1, 2001.
No. 73.

In the heating element of the present invention, at any point before encapsulation in an airtight outer packaging material, depending on the application, at least a part of one of the exposed surfaces of the base material or the coating material may be coated with an adhesive. Preferably, a layer is formed.

The pressure-sensitive adhesive layer is not particularly limited as long as it is a layer capable of adhering to the outer skin, and specific examples include a layer formed of a poultice or a pressure-sensitive adhesive.

Examples of the pressure-sensitive adhesive layer include a layer formed of a solvent-type pressure-sensitive adhesive, an emulsion-type pressure-sensitive adhesive, or a hot-melt-type pressure-sensitive adhesive.

The thickness of the pressure-sensitive adhesive layer is not particularly limited, but specifically, for example, as described in JP-A-10-1
One described in Japanese Patent No. 55827 is an example thereof.

In the heating element of the present invention, the pressure-sensitive adhesive layer on the exposed surface of the base material and / or the coating material contains a plaster agent, a compress layer containing a compress, or contains or carries a transdermally absorbable drug. It is desirable that the drug-containing layer has a heating effect, a compressing effect and a therapeutic or pharmacological effect with a drug, and specific examples of this pressure-sensitive adhesive layer are described in, for example, JP-A No. 10-155827. That have been included.

The heating element of the present invention is, for example,
It is manufactured by the method described in the specification of Japanese Patent Application No. 8-177404 filed on June 17, 1995 (domestic priority of Japanese Patent Application No. 7-196035 filed on July 8, 1995). .

[0111]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings, but the present invention is not limited thereto.

The heating element of the present invention according to the embodiment of the present invention has a length of 100 mm and a width of 70 m, as shown in the schematic sectional view of FIG.
An exothermic composition (fluid exothermic composition) 2 controlled by fluidity is laminated in a rectangular sheet-like packaging material 1 of m m, and a water-absorbent sheet 3 having air permeability covers the upper surface of the exothermic composition 2. In this case, the packaging material 1 is composed of a non-breathable base material 5 and a breathable covering material 6, and the sealing portion 4 is heat-sealed. It is obtained by fusion.

The base material 5 is made of a 100% polyester nonwoven fabric (having a thickness of 0.1 mm) so as to obtain sufficient flexibility.
50 mm, Soflon EP-40 manufactured by Unitech Corporation
40g / m2) In 5a, a thickness of 25
What laminated | stacked the non-breathable polyethylene film 5b of micrometer was used.

The coating material 6 used was the same as that of the base material 5 and was subjected to a fine needle (diameter: 0.8 mm) perforation process (54 perforation interval: 10 mm).
The final air permeability of the coating material 6 is adjusted to be about 20 seconds / 100 ml by a Gurley type densometer.

Incidentally, the flowable exothermic composition 2 described below was
The base material 5 is laminated on the upper surface of the polyester nonwoven fabric 5a, the water-absorbent sheet 3 is further laminated on the heat-generating composition 2, and the coating material 6 is perforated to form a polyethylene film 6a. They are laminated so as to be in contact with each other.

The water-absorbing sheet 3 is made of a polymer sheet [(paper 18 g / m ² ) / (water-absorbing polymer Sanyo Chemical Co., Ltd.).
Sunfresh ST-100 12 g / m ² ) / (paper 18 g / m ² )] A material having a water absorption of about 10 times its own weight, which absorbs a part of the water and has a length of 88 m
It is formed by punching into a rectangular shape having a width of 58 mm and a width of 58 mm, that is, a shape excluding the sealing portion between the base material 5 and the coating material 6.

The exothermic composition 2 was produced by the following method. First, 10.0 parts by weight of activated carbon as a carbon component (SA-Super by Norit) and 100 parts by weight of iron powder (DKP manufactured by Dowa Iron Powder Co., Ltd.) as a heat generating component, and sodium chloride (sodium chloride) as a metal chloride. ) 4.0
Parts by weight, 0.9 parts by weight of CMC (trade name: Cellogen HH, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as a thickener, and polyolefin fibers (Chemibest FD, manufactured by Mitsui Chemicals, Inc.), which are void forming fibers
SS-5) 3.0 parts by weight and calcium hydroxide 0.2 parts by weight as a pH adjuster were mixed, and a raw material having a mixing ratio of 45.0 parts by weight of water was measured.

The powdery raw material excluding the iron powder was put into a mixer (Dalton 5DMr type, capacity 5 liters), the rotation speed of the blade was fixed at 63 rpm, and after mixing for 2 minutes,
Water was added and kneaded for 5 minutes. After the mixture became viscous, 60 parts by weight of iron powder was added, kneaded for 5 minutes, and the remaining iron powder was added and kneaded for 5 minutes to produce a fluid exothermic composition. It is.

Thereafter, the blades and the deposits in the container are cleaned, kneading is performed again for 5 minutes, the fluidity and viscosity are measured, and the water content is adjusted. The amount of water finally added was 48.50 parts per 100 parts by weight of iron powder (DKP manufactured by Dowa Iron Powder Co., Ltd.).
0 parts by weight.

The fluidity of this exothermic composition 2 was 5 kg / cm ^{2 as} measured by a texture analyzer.

In this example, the exothermic composition 2 was 85 mm long and 55 mm wide on the polyester nonwoven fabric 5 a on the base material 5 by screen printing using a stencil having a thickness of 0.5 mm.
mm, and the water-absorbing sheet 3 punched into a shape excluding the seal portion was removed from the heat-generating composition 2.
The water-absorbing sheet 3 is positioned and fixed on the heat-generating composition by the adhesive force of the heat-generating composition 2, and then the covering material 6 is laminated. A heating element was manufactured by sealing the seal portion 4 with the perforated polyethylene film 6a by heat sealing at a seal width of 7.5 mm.

The produced heating element is subsequently sent to a packaging step, and is enclosed in an outer bag made of a drawn polypropylene / aluminum vapor-deposited unstretched polypropylene film (not shown).

The exothermic composition 2 was made of a polyester nonwoven fabric 5
a) After being laminated on the upper surface, the water for barrier is gradually absorbed by the water absorbing sheet 3 covered from above. However, the time from the lamination of the exothermic composition 2 to the encapsulation in the outer bag is extremely short, and during this time, the moisture for the barrier in the exothermic composition 2 is reduced to such an extent that an exothermic reaction is possible. Since it is hardly absorbed by the water absorbing sheet 3,
The exothermic reaction hardly occurs.

Therefore, there is almost no possibility that heat generation of the exothermic composition 2 occurs in the manufacturing process, and loss due to an exothermic reaction,
There is no possibility that the quality of the heat-generating composition 2 is reduced.
Further, in the process from the mixing of the heat-generating composition 2 to the printing on the substrate 5, there is almost no possibility that the heat-generating composition solidifies, the yield decreases due to the solidification, the operation is interrupted, the operation time is restricted, and the cleaning of the manufacturing apparatus is performed. Various adverse effects such as difficulty and danger, frequent cleaning of the manufacturing apparatus, and difficulty in coagulation treatment can be prevented.

Further, since the exothermic composition 2 is controlled by the fluidity as described above, pumping is possible, and further, no excessive force is required when extruding from the coater, and the exothermic composition is promptly applied without imposing a load on the motor. Can be laminated on the upper surface of the base material 5, and the lamination area can be controlled with high accuracy.
The film thickness can be controlled to be very thin and uniform, and the heat generating composition 2 is prevented from moving in the packaging material 1 by the bonding force between the coating material 6 and the heat generating composition 2. Become like Further, by making the film thickness of the heat generating composition 2 thin, the heat generating body can be made ultra-thin.

After enclosing the heating element in an outer bag,
After 2 hours, the outer bag was broken and adhered to the body surface of the person, and when it was used normally, the exothermic temperature rose to about 38 ° C in about 1 to 2 minutes. An exotherm occurred for over 5 hours. During this use, the exothermic composition 2 did not move in the packaging material 10 at all, and average heat generation was observed over the entire surface.

In this case, it was recognized that the heat generation temperature was stable, the temperature did not vary, and the reliability was remarkably high. The reasons are as follows.

That is, in the present invention, the exothermic composition 2 is blended with void-forming fibers, which prevent the volume change due to the exothermic reaction and gradually enlarge the air supply passage. It can be understood that the contact between the exothermic substance and the air formed inside is extremely good, and as a result, the exothermic reaction lasts for a long time.

It was also an issue to reduce the amount of the thickening agent which reduces the efficiency of the exothermic reaction and to maintain proper fluidity in the production. However, the amount of the thickening agent was reduced by blending the void forming fiber. Even if the fluidity can be maintained properly, furthermore, the air supply passage is gradually expanded by the voids formed by the void-forming fibrous material,
After forming the exothermic composition, the moisture in the exothermic composition is transferred from the exothermic composition layer to the water-absorbing sheet, and the water is consumed by the reaction. Accordingly, the water can be smoothly moved from the water-absorbing sheet to the heat-generating composition layer, so that the water content can be quickly maintained in an equilibrium state, so that the temperature of the process and the product can be quickly inspected.

Further, at the start of use, the exothermic composition layer is in an optimal exothermic state with a small moisture barrier.
A rapid exothermic reaction can be initiated, and when the moisture of the exothermic composition layer is consumed due to the progress of the exothermic reaction, the water is successively replenished from the water-absorbing sheet. Many problems of the viscous exothermic composition can be solved, for example, a heating element having good reaction efficiency can be obtained.

In addition, by blending the void-forming fibers with the heat-generating composition, the fibers are entangled, the adhesion to a kneading device or the like is reduced, and the fibers can be easily cleaned without washing with water, so that sewage treatment becomes unnecessary. There are good environmental and economic benefits.

In particular, in the case of production by the gravure printing method, the adhesion to the plate is reduced, the separation of the plate when laminating on the packaging material or the water absorbing material is good and uniform lamination is possible, and this point is also extremely excellent. In addition, there are many advantages such as simplification of the device. In particular, for the void forming fiber, a fiber having a short fiber length can stably enhance the fluidity, and has a good lamination property, and the void ratio is effective for a fiber having a long fiber length, but the laminating property is deteriorated. The above range is desirable.

[0133]

As described above, the fluid exothermic composition according to the present invention has the above-mentioned constitution, that is, the exothermic composition for forming a heating element by being laminated and sealed in a packaging material. Since the exothermic composition is controlled by fluidity, the following remarkable effects are exhibited.

That is, in the present invention, by controlling the exothermic composition by fluidity, it does not require an excessive force when extruding from the coater, and is quickly laminated on the upper surface of the base material without imposing a load on the motor. It is possible to control the lamination region with high precision, and to control the film thickness very thinly and uniformly, and in the manufacturing process,
It is possible to use simple means such as printing technology or coating / transferring / printing technology, etc., and it is very easy and accurate to quantify (measure) and to improve the quality of the heating element. .

In the present invention, by controlling the exothermic composition by fluidity, the exothermic composition can be transported by a pipe or the like by a pump or the like, and air can be supplied from the raw material tank to the laminating step. Without contact with
It also has effects such as being able to be directly laminated on a packaging material.

Further, in the present invention, the exothermic composition controlled by the fluidity covers the periphery of the iron powder, in which the moisture is the exothermic substance, and the thickness of the moisture layer serves as a barrier to air, and Since the contact between the inside and the air is prevented, there is no loss of the heat generating material due to heat generation during the production, and the effects of preventing the deterioration of the quality are exhibited.

In addition, according to the present invention, after the exothermic composition controlled by the fluidity is laminated and sealed in a packaging material, the barrier moisture in the fluid exothermic composition is reduced by the packaging material and / or Alternatively, by moving to the water-absorbing sheet provided in the packaging material, as a result, continuous voids are formed inside the exothermic composition, so that the exothermic reaction inside the exothermic composition becomes smoother. Is also expressed.

In the present invention, by forming a continuous void inside the exothermic composition, the efficiency of the exothermic reaction is remarkably improved, and the iron powder oxidized by the exothermic reaction is further reduced. As a result of preventing the bonding, the flexibility of the heating element during or after use is not impaired, and effects such as improvement in flexibility and usability can be obtained.

Further, the present invention has the above-mentioned constitution, and when the above-mentioned fluid heat generating composition is used, a known transfer / transfer such as transfer, thick coating printing, gravure printing, offset printing, screen printing, stencil printing, spraying and the like can be used. By printing using printing technology, or coating, impregnating or coating with a head coater, roller, applicator, etc., it can be transferred and laminated on a substrate very easily, and it is possible to manufacture ultra-thin heating elements at high speed. In addition, there is an effect that the exothermic composition can be evenly distributed in the packaging material.

In the present invention, the embodiment in which the water-absorbing sheet is provided so as to cover the heat-generating composition layer except for the sealing portion between the base material and the coating material, the complete heat exchange between the coating material and the base material. Sealing becomes possible, and the water-absorbing sheet absorbs moisture for barrier in the exothermic composition and removes the barrier layer, thereby promptly increasing the temperature rise at the start of use,
By improving the sealing strength of the seal portion and the sealing property of the seal portion, the effect of preventing the exudation of iron ions is exhibited. In addition, by configuring in this manner, the base material and / or the packaging material Since it is not necessary to use a hydrophilic water-absorbing sheet as the covering material, there is an effect that the sealing strength and the sealing property can be drastically improved even by hot melt bonding.

Further, in the present invention, a thin sheet-like heating element, and further, the softness is further improved by the water-absorbing sheet, the flexibility is high, the heat generation temperature is stable, and overheating can be prevented, so that low-temperature burns can be reliably prevented. As a result, the safety is greatly improved.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a heating element according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wrapping material 2 Fluid heat generation composition 3 Water absorption sheet 4 Seal part 5 Base material 6 Coating material

Claims (14)

[Claims] An exothermic composition for forming an exothermic body by being laminated and enclosed in a packaging material, wherein the exothermic composition is controlled by fluidity. Exothermic composition. 2. The fluid exothermic composition according to claim 1, wherein the fluid exothermic composition is controlled by plastic fluidity. 3. The flowability at a temperature of 20 ° C. is 0.5
The flowable exothermic composition according to claim 1, wherein the composition is in a range of from about ²⁰ kg / cm ^{2 to about 20} kg / cm ² . 4. After the fluid exothermic composition is laminated and encapsulated in a packaging material, moisture in the fluid exothermic composition serving as a barrier is provided to the packaging material and / or the packaging material. 2. A continuous void is formed inside the fluid exothermic composition by moving to the absorbed water absorbing sheet.
4. The flowable heat-generating composition according to any one of items 3 to 3. 5. The fluid exothermic composition according to claim 1, wherein the fluid exothermic composition contains void-forming fibers. 6. The fluid exothermic composition according to claim 5, wherein the void forming fiber is a hydrophobic void forming fiber. 7. The fiber for forming voids has an average fiber length of 3 mm.
The fluid exothermic composition according to claim 5, wherein the composition has an average fiber diameter of 500 μm or less. 8. The fluid exothermic composition according to claim 5, wherein the void forming fiber is a multi-branched structure void forming fiber. 9. The fluid exothermic composition according to claim 8, wherein in the fiber for forming voids of the multi-branched structure, the average diameter of the trunk is 500 μm or less. 10. The fluid exothermic composition according to claim 8, wherein the branch portion of the multi-branched structure void forming fiber has an average diameter of 100 μm or less. 11. The fluid exothermic composition according to claim 5, wherein the void forming fiber is an organic and / or inorganic void forming fiber. 12. The fluid exothermic composition according to claim 5, wherein the void forming fiber is a polyolefin fiber. 13. A heating element characterized in that the fluid heat-generating composition according to claim 1 is laminated and encapsulated in a packaging material having air permeability at least in part. . 14. The heating element according to claim 13, wherein the air-permeable water-absorbing sheet covers one or both surfaces of the fluid exothermic composition.