JPH0317874B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an exothermic composition that generates heat upon contact with oxygen in the air.

That is, in the production of a heat-generating composition consisting of metallic iron, sodium chloride, activated carbon, water, and a filler, a pre-prepared mixture of sodium chloride, activated carbon, water, and a filler and a certain amount of metallic iron are individually mixed to improve air permeability. The present invention relates to a method for producing a heat-generating composition, characterized in that the heat-generating composition is filled into a packaging material containing the heat-generating composition, and then encapsulated in an airtight packaging material.

Conventionally, methods for producing exothermic compositions by chemical reactions of metallic iron can be broadly classified into the following two methods. Namely, (1) a method in which each component of metallic iron, sodium chloride, activated carbon, water, and a filler is uniformly mixed and prepared, filled into a breathable packaging material, and then sealed in an airtight packaging material. (2) A composition containing metal iron and water among the components of metal iron, sodium chloride, activated carbon, water, and a filler is separated and filled into an air-permeable packaging material, and then this is airtight. Method of enclosing in packaging material. Of these (1)
A composition is prepared in advance by uniformly mixing each component of metallic iron, sodium chloride, activated carbon, water, and a filler. This composition generates heat immediately upon contact with air. Therefore, it is necessary to prevent the composition from coming into contact with air from the time the composition is manufactured until it is filled into a breathable packaging material. For this reason, the composition is usually manufactured in a closed device in which the air is replaced with nitrogen gas, and the air in the device is also replaced with nitrogen gas until the packaging material is filled. This has the disadvantage that the device becomes complicated and the manufacturing cost of the device is also high. Furthermore, since a large amount of nitrogen gas is used during manufacturing, it is expensive and requires exhaust equipment to prevent nitrogen gas from leaking into the working environment.

In method (2), all the ingredients are not mixed,
In particular, since the metal iron and water are separated, they do not generate heat when they come into contact with air, but since they are separated and filled into breathable packaging materials, the structure of the breathable packaging material becomes complicated. There are drawbacks. That is, during manufacturing, a single bag of packaging material must be provided with two separate bag sections, each of which must be simultaneously filled with a measured amount. Furthermore, the separated parts of the two separated bags must be easily removed to form one bag. Unlike method (1), this method does not require any measures to avoid contact with air during production, but it has the disadvantage that the packaging material becomes complicated.

Furthermore, the heat-generating composition produced by this method requires the user to remove the separated portion between the two bags and mix the two bags before use, which is not convenient for the user.

The present inventor has elucidated the advantages and disadvantages of the above two manufacturing methods, and has researched a more economical and simple method of manufacturing a heat-generating composition, and as a result, has arrived at the present invention.

The invention particularly relates to the production of exothermic compositions consisting of metallic iron, sodium chloride, activated carbon, water and fillers; (a) a pre-prepared mixture of sodium chloride, activated carbon, water and fillers; and (b) metallic iron. A method for producing a heat-generating composition, comprising: preparing a certain amount of each of the following, and simultaneously filling both of them into a single chamber of air-permeable packaging material; and then encapsulating the packaging material in an airtight packaging material. It provides:

In the present invention, a homogeneous mixture of other components except metallic iron is prepared in advance. This can be easily produced by sprinkling or spraying a mixture of activated carbon and filler with sodium chloride and, depending on the formulation, a solution of the filler dissolved in water. Since this mixture does not generate heat even when it comes into contact with air, it does not require any equipment or operations such as nitrogen gas replacement. This mixture can therefore be prepared in large quantities and stored in plastic bags to prevent loss of moisture. During manufacturing, the mixture and metal iron are individually weighed in predetermined amounts, and both are simultaneously filled into a single chamber of air-permeable packaging material. This filled material is then encapsulated in an airtight packaging material to obtain a heat generating composition. Furthermore, when filling these materials, in order to mix the mixture of activated carbon, sodium chloride, water, and filler with metal iron, for example, an obstacle is set up on the way to the packaging material so that they collide and mix. The device can also be devised. Furthermore, in the manufacturing method of the present invention, the mixture and metal iron are mixed at the same time as they are filled into the air-permeable packaging material, and the time from filling until the mixture is sealed in the air-tight packaging material is shortened. is also short-lived. Therefore, although there is some contact with air during this period, production can be performed without generating heat.

In the conventional method described above, even when nitrogen gas replacement is performed, the hopper container and the like that supply the exothermic composition reach a high temperature that cannot be touched by hand. This is considered to be due to the fact that the original heat generating performance of the heat generating composition is not maintained and there is a large loss due to heat generation during production. On the other hand, according to the present invention, as detailed above, there is no loss and a heat generating composition having the original performance can be obtained.

Furthermore, in the conventional method (1), as well as the loss of heat generation, the heated composition becomes a solid and is mixed in the composition. These exothermic compositions are originally used for the purpose of keeping people warm by applying them to the human body.
Mixing stiffness may cause discomfort or pain, which is not desirable. According to the manufacturing method of the present invention, an excellent heat-generating composition that is completely free of hardness and soft even when applied to the body can be obtained.

Oxygen absorbers exhibit a reaction system similar to that of exothermic compositions, but in this case, the reaction is slow and does not generate heat, and their useful life is long. on the other hand,
In the case of the exothermic composition of the present invention, the reaction occurs rapidly in a short period of time, and although there are many similarities in principle, the two are very different in detail. For example, in the case of oxygen absorbers, it is not necessary to produce all raw materials in the presence of an inert gas such as nitrogen gas. In the present invention, if metal iron coated with sodium chloride in advance is used, the exothermic temperature will be lowered, the exothermic properties will deteriorate during storage, and the composition will lose its characteristics as an exothermic composition. Therefore,
As in the present invention, sodium chloride must be prepared in advance with something other than metal iron.

The heat-generating composition produced in the present invention contains metallic iron as a main component, and this metallic iron can be in powder form such as reduced powder, electrolytic powder, spray powder, or crushed oak powder. In general, particles with an average particle size smaller than 50 mesh are suitable, and even if they are not necessarily highly pure, they may contain impurities to the extent that they do not impair the effects of the present invention. can include cast iron powder. In addition, as a filler used in the composition of the present invention, silicic acid is used because it can maintain quality and performance during storage, generate heat at a constant temperature for a long time, and eliminate the need for kneading or shaking during that time. Sodium hydrate salts are used. In addition, diatomaceous earth, wood flour, raw ash, calcium sulfate, acid clay, zeolite, etc. can be used as fillers, and by using these materials, the fluidity and flexibility of the exothermic composition are improved. , it feels good when you put it on your body, and it generates heat smoothly. In addition, water-absorbing polymers can also be used for the purpose of absorbing water and stably retaining it. When a water-absorbing polymer is used, even if pressure is applied to the exothermic composition, water can be stably retained without separating, and the reaction of the exothermic composition is not affected at all. Examples of this water-absorbing polymer include CMC type, starch-polyacrylonitrile hydrolyzate, starch-polyacrylate crosslinked product, saponified vinyl acetate-methyl acrylate copolymer, polyacrylonitrile hydrolyzate, and sodium polyacrylate. Cross-linked materials etc. can be used.

As described above, the heat-generating composition of the present invention is filled into a breathable packaging material. This packaging material controls the contact of the composition with oxygen and also prevents the composition from leaking out. Therefore, the packaging material needs to be one that does not allow the mixture of the composition to escape to the outside and allows a suitable amount of air (oxygen) to pass through.
This packaging material desirably has uniform air permeability throughout when the heat-generating composition is filled and packaged. Packaging materials that differ in their air permeability or have local air permeability are not suitable.
For example, paper, synthetic paper, or non-woven fabric such as nylon or polyester, or a film with holes made in it, can be used as paper, synthetic paper, or
Alternatively, one laminated on a nonwoven fabric is preferable.

In addition, as an airtight packaging material for enclosing a packaging material filled with a heat-generating composition, one made of an airtight film laminated with a film of OV-polyethylene or polypropylene coated with vinylidene chloride, polyester, etc., and polyethylene. preferable.

Next, the present invention will be explained with examples.

However, "parts" in the examples indicate "parts by weight."

Example 1 6 parts of sodium chloride and 9 parts of sodium metasilicate
A suspension of 6 parts of aqueous salt in 48 parts of water is made from diatomaceous earth.
It was impregnated with a mixture of 28 parts and 12 parts of activated carbon. The measured values of 30 g of this mixture and 30 g of cast iron powder with an average particle size of 80 mesh using a Gurley densometer were as follows.
A 10 x 13 cm packaging material made of nylon spunbond polyethylene with an air permeability of 15-20 seconds/100 ml was simultaneously filled. Next, an airtight packaging material (13 x 17 cm) made of vinylidene chloride coated polypropylene 50μ - polyethylene 40μ film.
A heat-generating composition was obtained.

Example 2 7 parts of sodium chloride and 9 parts of sodium metasilicate
A solution prepared by suspending 7 parts of water salt in 47 parts of water was added to 14
1 part, 23 parts of wood flour, and 2 parts of saponified vinyl acetate-methyl acrylate copolymer. 25 g of this mixture and 35 g of cast iron powder with an average particle size of 100 mesh
The husband and husband simultaneously filled the air-permeable packaging material made of three layers: synthetic paper made of pulp and synthetic resin, polyethylene cloth, and polyethylene, with a value measured by a Gurley densometer of 18 to 23 seconds per 100 ml. A filling of 9.5×14 cm was obtained. Then OV-
A heat-generating composition was obtained by sealing it in a 12.5 x 17.5 cm airtight packaging material bag made of polyethylene film.

Example 3 9 parts of sodium chloride was dissolved in 27 parts of water and sprinkled on a mixture of 54 parts of diatomaceous earth and 10 parts of activated carbon to impregnate it. 40g of this mixture and 20g of reduced iron powder (RD-3. manufactured by Nippon Steel Powder) were simultaneously mixed into three layers of rayon paper, polyethylene cloth, and polyethylene, each having an air permeability of 8 to 12 seconds per 100ml measured using a Gurley densometer. The packaging material (10 x 13.5 cm) was filled with: This was then encapsulated in an airtight packaging material (13 x 17 cm) made of a film of vinylidene chloride coated polyester 15μ and polyethylene 60μ to obtain a heat generating composition.

Performance Test The exothermic composition produced by the production method of the present invention in Examples 1, 2, and 3 above was taken out from the airtight packaging material, wrapped in four towels in a room at a room temperature of 20°C, and the temperature was measured using a resistance thermometer. . Both exothermic compositions have a maximum temperature of 60 to 70℃, and a duration of 20 degrees above 40℃.
It showed excellent heat generation performance over hours.

Claims (1)

[Claims] 1. In the production of an exothermic composition comprising metallic iron, sodium chloride, activated carbon, water and a filler; (a) a previously prepared mixture of sodium chloride, activated carbon, water and a filler; and (b) Preparing a certain amount of each of metal iron; and filling both of them simultaneously into a single chamber of air-permeable packaging material; and then encapsulating the packaging material in an airtight packaging material. Method.