JP3319699B2 - Heating structure and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a heating element comprising a heating agent which generates heat in the presence of air (hereinafter simply referred to as a heating agent) in a breathable bag (hereinafter referred to as a heating agent storage bag). The present invention relates to a heat generating structure housed in a non-breathable bag (hereinafter, referred to as an outer bag) and a method for manufacturing the same.

[0002]

2. Description of the Related Art A heating element in which a heating agent is stored in a heating agent storage bag is widely used as a warmer. In addition, a flat adhesive heating element in which one side of a heating agent storage bag is made of a base sheet provided with an adhesive and the other side is a ventilation surface is useful because it can be attached to underwear with an adhesive, and recently, A type in which a plaster is provided instead of an adhesive has appeared, and a heating element of this type can be directly attached to a body, and thus is used as a medical device.

[0003] These heating elements are stored in an outer bag when not in use, and are taken out of the outer bag and used when used.

[0004] The heating element and the adhesive heating element as a medical device generate heat during the heating of the heating agent (ie, during the use of the adhesive heating element).
The inside of the heating agent storage bag is depressurized with respect to the outside air pressure,
The exothermic agent is pinched and fixed by the exothermic agent storage bag. Such a heating element is formed in a state where the heating agent is stored in the heating agent storage bag, and is immediately stored in the outer bag. Further, a step of flattening the heating agent after the heating element is formed and / or after the heating element is stored in the outer bag is incorporated. However, moving the heat generating structure in which the heat generating element is stored in the outer bag,
When the heating element is taken out of the outer bag and moved, the heating agent moves in the heating agent storage bag and is unevenly distributed. Therefore, when the heating element is used, the heating agent is sandwiched and fixed in an unevenly distributed state, and the shape of the heating element does not tend to be a flat sheet. This tendency becomes remarkable especially when the amount of the heating agent is reduced and the thickness of the heating element is reduced in order to improve the feeling of wearing on the body part, resulting in non-uniform dispersion of the heating agent and uneven thickness, resulting in a heating effect. Has the disadvantage of adversely affecting

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat generating structure in which the movement of a heat generating agent in a conventional heat generating structure is suppressed, and a method of manufacturing the same.

[0006]

The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, achieved the intended purpose by adjusting the amount of gas existing inside the heat generating structure to a specific amount. They have found that they can do so and have reached the present invention.

That is, the present invention provides a heat generating structure in which a heat generating element containing a heat generating agent in a heat generating agent storage bag is stored in an outer bag, and the heat generating agent is sandwiched and fixed by the heat generating agent storing bag during heat generation. Wherein the amount of gas present inside the heat generating structure is 70% or less of the apparent volume of the heat generating agent, and the heat generating agent that generates heat in the presence of air is stored in the heat generating agent storage bag. When the heat generating element is housed in a non-breathable bag and the heat generating agent is held and fixed by the heat generating agent storage bag during heat generation, the amount of gas existing inside the heat generating structure generates heat. Removing air from the heating agent storage bag when storing the heating agent in the heating agent storage bag and / or removing the heating element into the outer bag so that the heating agent is 70% or less of the apparent volume of the heating agent. Heating structure characterized by removing air from outer bag A method for manufacturing.

[0008] In the present invention, the gas existing inside the heat-generating structure means that the heat-generating structure is usually manufactured in an air atmosphere, so that air exists inside the heat-generating structure immediately after the production. Since oxygen in the air is sequentially consumed by the exothermic agent, it means gas (substantially nitrogen) remaining after oxygen consumption.

Further, in the present invention, the amount of gas existing inside the heat generating structure means that the amount of gas present in the heat generating structure is
It refers to the total amount of gas occupied between the outer bag and the heating element.

[0010] The cause of the movement of the exothermic agent in the exothermic agent storage bag caused when the exothermic body is moved when the exothermic body is moved or the exothermic body is removed from the outer bag is moved. As a result of intensive research, the heat generating structure of the present invention has been completed based on the following findings.

That is, in the heating element of the present invention, during the heating of the heating agent (ie, during use of the heating element), the inside of the heating agent storage bag is depressurized with respect to the external pressure, and the heating agent is heated. It is held and fixed by a storage bag. Normally, since the formation of the heating element and the production of the heating structure are performed in an air atmosphere, the inside of the heating structure immediately after production (ie,
Air exists inside the heating element and between the outer bag and the heating element). The oxygen in the air is usually annihilated by the reaction with the exothermic agent in the heating element by the time the heating element is used, and nitrogen is present in the heating structure. The gas (nitrogen) between the outer bag and the heating element gradually flows into the heating element through the ventilation surface of the heating agent storage bag until a gaseous component and pressure equilibrium state is attained.
The time required for the heating agent to reach a state in which the heating agent is sandwiched and fixed by the heating agent storage bag during use is longer in accordance with the amount of gas (nitrogen) in the heating member. Movement within the agent storage bag is facilitated.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The exothermic agent of the present invention includes, for example, (a) metal powder such as iron powder, (b) water, (c) an oxidizing aid such as a metal halide or sulfate, and (d) Compositions containing water retention agents such as wood flour, hillite, activated carbon, and water-absorbing polymers as main components. In addition, these components (a) to (d) include inorganic salts as hydrogen generation inhibitors and binders as compounding aids. Alternatively, a composition to which a surfactant or the like as an impregnation aid is added may be used. Preferably, a composition comprising at least iron powder, water, a metal halide salt and activated carbon is used as a heating agent. The apparent specific gravity of the exothermic agent is usually 0.6 to 0.85. The apparent specific gravity is determined from the weight of the exothermic agent when the exothermic agent is filled into a container having a predetermined volume and the predetermined volume.

The filling amount of the exothermic agent stored in the exothermic agent storage bag of the present invention, when expressed by its apparent volume, is 0.05 ml / cm ^{2 to} 0.5 ml / 0.5 to the effective area of one side of the storage bag. c
A ratio in the range of m ² is preferably applied. More preferably a proportion ranging from ^{0.1ml / cm 2 ~0.35ml / cm 2} . When the ratio is within such a range, it is easy to maintain the shape of the heating element in the step described later, the shape of the heating element in the outer bag in the step described later, and the shape of the heating element in use at a flat preferable shape. is there. The effective area on one side of the heating agent storage bag means the area of the heating agent storage portion excluding the sealing portion of the heating agent storage bag.

The exothermic agent storage bag of the present invention has one surface made of a gas-permeable surface and the other surface made of a non-air-permeable material, and usually has a gas-permeable surface made of a porous material.

The porous packaging materials include (1) porous sheets (trade name: NF sheet or Porum (made by Tokuyama), trade name: Cellpore (made by Sekisui Chemical), trade name: Breslon (made by Nitto Denko) ) Etc. or laminated sheet of porous sheet and nonwoven fabric
Air-permeable sheet (trade name: Tyvek (manufactured by DuPont)) made by laminating polyethylene fibers and heating and pressurizing; or (2) a plastic film having vent holes provided in advance on a porous sheet. Laminated ones are applied. A particularly preferred porous packaging material is a laminated sheet of a porous sheet and a nonwoven fabric.

When the exothermic agent is stored in the exothermic agent storage bag using such a porous packaging material, the exothermic agent is rich in flexibility so as to fit along the curved part of the body, there is no powder leakage of the exothermic agent, and the exothermic agent is stored. A sheet-like heat generating structure capable of preventing the movement and bias of the sheet can be formed.

As the non-breathable packaging material, a base sheet or an adhesive packaging material is applied.

The base sheet may be a single or a plurality of materials selected from the group consisting of plastic films, nonwoven fabrics, porous sheets, and foamed sheets having good heat seal properties. Are applied. Preferably, at least polyethylene, ethylene-
A plastic film in which a single film or a plurality of films selected from the group consisting of a vinyl acetate copolymer, an ethylene-acrylate copolymer, and an ethylene-methacrylate copolymer are laminated, and a nonwoven fabric in the plastic film. Laminated sheets are applied.

As the adhesive wrapping material, the above-mentioned base sheet is used from the inside.
A sheet, a pressure-sensitive adhesive and a release sheet are arranged in this order, and the pressure-sensitive adhesive is provided on a desired portion of the surface of the base sheet.

The release sheet may be made of one or more base materials selected from the group consisting of synthetic paper, polyethylene film, polypropylene film and polyester film, the surface of polyethylene-laminated paper or resin-impregnated paper. To form a cured film of a curable organopolysiloxane composition.

Examples of the adhesive include generally known acrylic and rubber-based adhesives used for an adhesive heating element or a medical device heating element.
An adhesive such as vinyl acetate can be used, and an acrylic or rubber (for example, SIS) is preferable. These can be applied in any of an organic solvent type, an aqueous type and a non-solvent type.

The pressure-sensitive adhesive is applied to the outer surface of the base sheet, and does not necessarily have to be provided on one entire surface of the exothermic agent storage bag, but may be provided partially, for example, on the left and right sides.

Further, by providing a dashed line, a cut line, a gripping portion, a tongue piece, or the like on the surface of the peeling sheet or the non-adhesive-coated portion of the sheet, the peeling when using the sheet-like heat generating structure is performed. This is preferred because the sheet operability is further improved.

In the production of the exothermic agent storage bag, if the exothermic agent storage bag does not require much sealing strength, an adhesive layer may be provided on a desired portion of the inner surface of the adhesive packaging material. Good.

As a method for sealing the porous packaging material and the base material sheet or the adhesive packaging material, a heat sealing method,
Examples include a method using an adhesive and a method combining both of them.

The outer bag of the present invention has a non-breathable packaging material on both sides. The non-breathable packaging material is composed of at least one of the above-described base sheets and at least one of a film selected from polyvinylidene chloride, polyvinyl alcohol, an aluminum vapor-deposited film, an aluminum foil, and the like. Low composite film is applied. The oxygen permeability and the moisture permeability are described in JIS S4100 (1996), section “Airtightness of outer bag material”.

The dimensions of the heating element in the heating structure of the present invention are such that the effective area of one side of the heating agent storage bag is 4 cm ^{2 to} 300 cm.
cm ^2, preferably particularly in 20cm ² ~150cm ^2, the shape is generally rectangular, although a circular or the like are not particularly limited. The size of the outer bag may be any size that is economical and easy to store the heating element in accordance with the shape and size of the heating element. Usually, the inner size of the outer bag is 10 mm to 30 mm from the outer dimension of the heating element.
It is applied in the range that increases.

Next, the method of manufacturing a heat generating structure according to the present invention is characterized in that air is removed from the heat generating agent storage bag when the heat generating agent is stored in the heat generating agent storage bag and / or when the outer bag of the heat generating element is stored. There is no particular limitation as long as air is removed from the outer bag.

An industrial manufacturing method of the heat generating structure of the present invention will be described. The production method is a continuous method, and usually involves successively successive steps and steps, steps and, if necessary, successive steps.

Step: While two sheets of packaging material continuously supplied to a sealing die roll having a concave portion and a convex portion (seal portion) are heat-sealed by the sealing die roll,
While forming the exothermic agent storage bag, the exothermic agent is filled into the exothermic agent storage bag, and after filling, the unsealed portion is heat-sealed to form a heating element (hereinafter referred to as a process-A method) or for the sealing. A magnetic force transfer method which is continuously supplied to a die roll (for example, Japanese Patent Application Laid-Open No.
JP-A-6-54876, JP-A-6-80108
JP-A-6-191505, JP-A-7-12419
No. 3, Japanese Patent Application No. 8-179916, etc.)
While continuously supplying the packaging material on which the exothermic agent is mounted and the packaging material coated with the exothermic agent to the sealing die roll, the exothermic agent storage bag is formed by heat sealing with the sealing die roll. Together with the heating element.

Step: A step of flattening a heating agent in the heating element.

Step: A heating element is filled in the outer bag while forming the outer bag while sealing the two packaging materials continuously supplied to the sealing die roll with the die roll, and after filling, the unsealed portion is removed. Forming a heat generating structure by heat sealing;

Step: A step of further flattening the exothermic agent in the exothermic structure.

Since these steps are usually performed in an air atmosphere, in the steps and the steps, air is simultaneously sealed in the exothermic agent storage bag and the outer bag, respectively. Therefore, the amount of gas present inside the heat generating structure by the time the process and / or the process is completed is reduced to 7 times the apparent volume of the heat generating agent.
Air is removed so as to be 0% or less, preferably 50% or less. In particular, when the amount of the exothermic agent is reduced to reduce the thickness of the exothermic body, for example, when the apparent volume of the exothermic agent is 0.3 ml / cm ² or less with respect to the effective area on one side of the exothermic agent storage bag, heat is generated. It is preferable to remove air so that the amount of gas existing inside the structure is 50% or less of the apparent volume of the exothermic agent.

As a method for removing air, the following method can be used.

(1) In the step and / or the step,
When using a die roll for sealing in which a non-heat-conductive elastic material (for example, a heat-resistant sponge-like or foamed material) is adhered to a desired portion of the concave portion in an appropriate shape and thickness. A method that removes air by holding the packaging material with an appropriate pressure with a non-heat-conducting elastic material.

(2) Step-A In the method and / or step, a heating roll or a heating structure being formed is pressed by using a pressing roll different from the sealing die roll to remove air.

(3) A method in which the methods (1) and (2) are used in combination.

In the step, it is preferable that the shape of the exothermic agent stored in the exothermic agent storage bag is flat, and that the amount of air inside the exothermic body be 60% or less of the apparent volume of the exothermic agent. Of air is preferably removed. More preferably, the amount of air in the part is 50% or less of the apparent volume of the exothermic agent.

In the step, the shape of the exothermic agent or the shape of the heating element stored in the outer bag is preferably flat,
It is preferable to remove the air from the portion so that the amount of air occupying the portion between the outer bag and the heating element is 85% or less of the apparent volume of the heating agent. More preferably, the amount of air in the part is 75% or less of the apparent volume of the exothermic agent.

As a method of flattening the shape of the heating agent stored in the heating agent storage bag, the heating element is tilted and / or vibrated until the heating element is reduced in pressure after the heating element is formed. There is a way to do it.

[0042]

Next, preferred embodiments of the present invention will be illustrated, but the present invention is not limited thereto.

Examples 1 to 6 and Comparative Examples 1 and 2 The exothermic agent storage bag and exothermic agent constituting the exothermic body are shown in Table 1, respectively, as a porous packing material and a non-ventilated surface as a ventilation surface of the storage bag. The adhesive packaging material and the exothermic agent were used.

The exothermic agent is filled into the exothermic agent storage bag whose three sides are sealed and one side is unsealed, and after the air in the bag is removed by pressing the bag with a heat-resistant sponge plate, the unsealed portion is sealed. Thus, a heating element was formed. The exothermic agent was uniformly dispersed throughout the exothermic agent storage bag using a pressing roller immediately after formation, and flattened to obtain a sheet-like exothermic body. The size of the heating element was (external dimensions) 100 × 130 mm, and the horizontal and vertical seal width was 5 mm. Table 2 shows the exothermic agent loading. Thus, a plurality of heating elements were formed. Immediately after the formation of one of the heating elements, the amount of air in the heating element was measured according to the air / gas amount measurement method described below.

Next, the heating element is housed in an outer bag whose three sides are sealed and one side is unsealed, and the air in the outer bag is removed as much as possible in the same manner as described above to substantially reduce the amount of air in the outer bag. After that, the unseal portion was sealed to produce a heat generating structure.
The width of the outer and vertical seals was 5 mm. Thus, a plurality of heat generating structures were manufactured.

With respect to one of the heat generating structures, one minute after the production, the heat generating element was taken out and shaken vertically 5 to 6 times to observe the state of movement of the heat generating agent inside the heat generating element.
The other one was allowed to stand for 22 hours after production, and then the amount of gas inside the heat generating structure was measured according to the method for measuring the amount of air and gas described below. Table 2 shows the results.

Measurement of air volume and gas volume: A sample (heating element or heat generating structure) was placed in a cylinder 500 containing 350 ml of water.
The sample was immersed in water and the volume of the sample was measured. Then, the sample was broken and the total volume of the raw materials of the sample was measured in the same manner as described above. The difference between the two volumes was determined as the amount of air or gas. The measurement temperature is 23 ° C.

In Examples 1 to 6, the ratio of the moving area of the exothermic agent inside the heating element was small and good.

In Comparative Examples 1 and 2, the moving area ratio of the heating agent inside the heating element was large, and the heating element could not maintain a flat sheet shape.

Examples 7 to 20 and Comparative Examples 3 to 12 The air in the heating element was removed as much as possible to reduce the amount of gas in the heating element to substantially zero, and the amount of air removed in the outer bag was changed. The procedure was performed in the same manner as in Example 1 except that the outer bag size (length and width of the seal width was 5 mm) and the amount of the heating agent charged were as shown in Table 3. In addition, about the heating element size (outside dimension),
Examples 7 to 11 and Comparative Examples 3 to 6 are 100 × 130 mm
(Height and width seal width: 5 mm), Examples 12 to 16 and Comparative Examples 7 to 9 were 100 × 70 mm (Height and width seal width: 5 m)
m), and Examples 17 to 20 and Comparative Examples 10 to 12 were 130 × 190 mm (vertical and horizontal seal width 5 mm).

The amount of air between the outer bag and the heating element was measured immediately after the production of the heating structure according to the method for measuring the amount of air and gas described above.

After the heating structure was left for 22 hours after production, the gas amount inside the heating structure was measured in the same manner as in Example 1. In addition, the moving state of the exothermic agent inside the heating element was observed by a method in which the heating element was taken out of another heating structure and shaken vertically 5 to 6 times. The results are shown in Tables 3 and 4.

In Examples 7 to 20, the ratio of the moving area of the exothermic agent inside the heating element was small and good.

In Comparative Examples 3 to 12, the ratio of the moving area of the heating agent inside the heating element was large, and the heating element could not maintain a flat sheet shape.

[0055]

[Table 1]

[0056]

[Table 2]

Note) The moving area ratio of the exothermic agent is the ratio (%) of the one-sided area of the space in the exothermic agent storage bag generated by the movement to the effective area of one side of the exothermic agent storage bag (the same applies hereinafter). .

[0058]

[Table 3]

[0059]

[Table 4]

[0060]

According to the present invention, since the amount of gas present inside the heat generating structure is adjusted, the movement of the heat generating agent in the conventional heat generating structure can be suppressed, and the flat sheet-like heat generating member can be suppressed. When the heat-generating element is taken out of the heat-generating structure and used, the heat-generating element maintains a flat sheet-like shape, and the heat-generating structure can be provided in which the feeling of mounting and the heating effect are further improved. Further, a method for manufacturing the heat generating structure can be provided.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-149272 (JP, A) JP-A-1-201253 (JP, A) JP-A-62-347 (JP, A) 15918 (JP, U) Actually open sho 59-116029 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61F ^7/ 00-7/ ¹⁰

Claims (10)

(57) [Claims] 1. A heating element comprising a heat-generating agent that generates heat in the presence of air in a gas-permeable bag, is housed in a non-gas-permeable bag, and the heat-generating agent is held and fixed by the gas-permeable bag during heat generation. A heat generating structure, wherein the amount of gas present inside the heat generating structure is 70% or less of the apparent volume of the heat generating agent. 2. The heat-generating structure according to claim 1, wherein the air-permeable surface of the air-permeable bag is made of at least a porous packaging material. 3. The apparent volume of the exothermic agent stored in the breathable bag is 0.05 ml / c with respect to the effective area on one side of the breathable bag.
The heating structure according to claim 1, wherein the ratio is in a range of m2 to 0.5 ml / cm 2. 4. A heating element comprising a heat-generating agent that generates heat in the presence of air in a gas-permeable bag is stored in a non-gas-permeable bag, and the heat-generating agent is held and fixed by the gas-permeable bag during heat generation. In manufacturing the heat generating structure, air is removed from the air permeable bag when the heat generating agent is stored in the air permeable bag so that the amount of gas existing inside the heat generating structure is 70% or less of the apparent volume of the heat generating agent. removing the manufacturing method of the heating structure, characterized in that the removal of air from the air-impermeable bag during the storage of the non-breathable bags及beauty-heating body. 5. An exothermic agent which generates heat in the presence of air is air-permeable.
The heating element stored in the bag is not stored in the impermeable bag.
The exothermic agent is pinched and fixed by a breathable bag during heat generation
Exist inside the heat generating structure when manufacturing the heat generating structure
So that the amount of gas generated is 70% or less of the apparent volume of the exothermic agent
When the exothermic agent is stored in the breathable bag,
A method for manufacturing a heat generating structure, comprising: 6. A heat-generating agent which generates heat in the presence of air is air-permeable.
The heating element stored in the bag is not stored in the impermeable bag.
The exothermic agent is pinched and fixed by a breathable bag during heat generation
Exist inside the heat generating structure when manufacturing the heat generating structure
So that the amount of gas generated is 70% or less of the apparent volume of the exothermic agent
In addition, when storing the heat-impermeable air-impermeable bag,
A method for producing a heat generating structure, comprising removing air. 7. A method for removing air from a breathable bag.
The amount of air inside the heating element is 60% or less of the apparent volume of the heating agent.
Claims characterized by removing air so that it is below
6. The method for producing a heat generating structure according to 4 or 5. 8. A method for removing air from an air-impermeable bag.
The amount of air occupied by the air-impermeable bag and the heating element
Air to less than 85% of the apparent volume of
7. The production of a heat generating structure according to claim 4, wherein
Method. 9. A breathable bag having at least a ventilation surface.
4. The method according to claim 4, wherein the second member is made of a porous packaging material.
9. The method for manufacturing a heat generating structure according to any one of items 8. 10. Apparent body of heating agent stored in air permeable bag
The volume is 0.05 ml / with respect to the effective area on one side of the breathable bag.
cm2 to 0.5 ml / cm2
The heat generating structure according to any one of claims 4 to 9,
Manufacturing method of the structure.