JPS59145277A - Heat generating composition for feet warming - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which has a relatively small volume and in which muximum attainable temperature is high, by using a specified water- absorptive resin as a water retaining material for a heat generating compsn. for feet warming, which utilizes chemical heat generation. CONSTITUTION:A water-absorptive resin having the max. particle size of 4mm. or below and water absorptivity [ml of water/g of water-absorptive resin) of 30 or above is used. 4-30g of iron powder, 0.01-10g of an oxidation accelerator, 0.5- 15g of water, 0.2-10g of activated carbon and 0.01-4g of said water-absorptive resin are blended together.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a heat insulating bag that has a higher heat generation temperature than a chemically heat-generating thermal bag (hereinafter referred to as a heat-generating bag) used for the torso under normal heat-generating conditions, and has a relatively small volume. It relates to heat-generating compositions for warming purposes.

In winter or in a cold environment, the skin temperature at the toes cannot be prevented from dropping, which is a cause of illness.

On the other hand, even if you use various types of shoe insoles that are commercially available as foot warmers, these insoles are simply heat insulators and cannot essentially prevent your feet from getting cold. There has been a demand for a foot warming device that can actively heat the feet.

For this reason, there has been a movement in the past 1-2 years to use bags containing heat-generating agents as foot-warming bags.

However, there were various restrictions associated with thermal bags for foot warming, which made it extremely difficult to put them into practical use, and wide (K) had not been put into practical use.

Heat-generating bags for foot warming are placed inside footwear such as shoes, tabi socks, and slippers, and are typically placed on the inner soles of shoes. In order to avoid causing discomfort or discomfort to the user when the bag is used, the heat generating bag for foot warming must be quite thin, that is, the volume of the heat generating composition for foot warming must be sufficiently small. In addition, the amount of air flowing through footwear such as shoes, tabi, and slippers in cold weather is low in terms of specific heat.
In order to generate sufficient heat in a low ambient temperature, the bag must have a higher heat generation temperature than the heat generating bag used for the body under normal heat generating conditions. A heat generating composition that satisfies both of the above two essential requirements has not yet been known.

In order to obtain a heat-generating composition that has a large calorific value per unit volume, the selection of the water-retaining material as well as the air permeability of the bag material and the blending ratio of each component are extremely important.

Conventional heat-generating grommet materials for heat-generating bags used for body parts, etc., have used many materials for water retention, such as activated carbon, wood flour, vermiculite, sepiolite, zeolite, silica gel, and clay. K, which is used as a heat-generating composition for foot warming and as a water-retaining material for things, has various problems. In other words, the two essential requirements are that the exothermic composition for foot warming must have a sufficiently small volume and that it must have a higher exothermic temperature than the exothermic bag used for the torso under normal exothermic conditions. However, when these water retaining materials are used, it has not been possible to obtain a heat generating composition for foot warming that satisfies the above two essential requirements. In addition, these water-retaining materials are easy to release water once they are applied, and the heat-generating bag for foot warming is used in a large size, such as when a heat-generating bag for foot warming is used by laying it on the inner sole of a shoe. If pressure is applied, there is also a risk that water will seep out from the outside of the foot heating bag.

As a result of extensive research, the present inventors have found that by using a water-absorbing resin with a water-absorbing capacity of 60 (water/water-absorbing resin g) or more as a water-retaining material, the water-absorbing resin can be used in a small volume and under normal heat generation conditions. We have succeeded in developing a heat-generating composition for foot warming that has a higher heat-generating temperature than heat-generating bags used for the torso.

That is, the present invention is a foot-warming heat-generating composition comprising at least iron powder, an oxidation promoter, water, activated carbon, and a water-absorbing resin having a water-absorbing capacity of 60 (Water Go/Water-Absorbent Resin g) or more. .

The heat generating composition for foot warming of the present invention is filled into a bag having air permeability and is put to practical use as a heat generating bag for foot warming. The amount of each component per bag varies depending on the grade of each raw material used, the allowable volume of the exothermic composition, the required exothermic performance and price, etc., and cannot be specified in general, but the Since it is preferable that the product has an extremely large volume, a low heat generation performance, and a low price per bag, the amount of each product that can be produced per bag is naturally limited.

The amount of each ingredient per bag is iron powder 4v~305+, oxidation promoter o, oig~10,9, water 0-51~1'5
,? , activated carbon 0.2g~iog and water absorption capacity 60
(water ml/water absorbent resin I) or more water absorbent resin o'
-oiy to 4I, preferably and has a water absorption capacity of 30 (water t
nl/Water absorbent resin I) Water absorbent resin on υ o, o
s, p~1.5g.

There are no particular restrictions on the iron powder and activated carbon used in the present invention, and those used for ordinary heat-generating bags can be used. The oxidation promoter used in the present invention is not particularly limited as long as it is an inorganic salt. For example, NaC1, CaC1
x, KCl.

BaC1z, AAICJ3, Katana C1x, N
a2S04-M#80. , NaBr, KBr and NaNOs, among many others.

The water-absorbing resin used in the present invention has a water-absorbing capacity of 30 (water/g of water-absorbing resin) or more, and the higher the water-absorbing capacity, the more preferably the water-absorbing resin has a water-absorbing capacity of 120 to 1.
．． 000 (water d/water absorbent resin g). Water-absorbing resins with such water-absorbing ability include inbutylene-maleic anhydride copolymer, polyvinyl alcohol-acrylate copolymer, starch-acrylate graft polymer, polyacrylate crosslinked product, and acrylic acid. Examples include salt-acrylic acid ester copolymers, hydrolysates of polyacrylonitrile crosslinked products, and acrylate-acrylamide copolymers, but this does not preclude the use of water-absorbing resins other than those mentioned above. The basic structure of these water-absorbing resins is that a light crosslinking bond is introduced into a polymer having an ionizable group.

In addition, the water absorption capacity in the present invention is measured by the tea bag method (
A paper bag filled with a water-absorbing resin sample is immersed in water for 6 minutes, and the water absorption capacity of the sample is measured.

The water-absorbing resin used in the present invention is powdery or granular in a dry state, and the shape of the granules is not limited. The maximum diameter of the powder or grains is preferably 4i+x or less. If the diameter is larger than 4 am, this will lead to uneven distribution of the water-absorbing resin in the heat-generating composition for foot warming. When put into practical use, it causes large variations in the product.

The water absorption capacity per unit N of the water absorbent resin used in the present invention is considerably greater than that of other water retention materials such as wood flour, activated carbon, vermiculite, sepiolite, zeolite, silica gel, and diatomaceous earth.

The heat-generating composition for foot warming of the present invention may contain various heat-generating aids such as metal powders, metal salts, and metal oxides in order to improve heat-generating performance.

Examples of metal powders include Cu, Ag, Pd, and Sn.
Examples of metal salts include CuCl2.
FeC1z.

FeC11z, Cu80< and Fe50<, etc. Also, examples of metal oxides include CuO, Mn0z,
M, 5'O and CaO, among many others.

In order to prevent the generation of hydrogen, a small amount of a weak acid salt and/or hydroxide of an alkali metal, or a weak acid salt and/or hydroxide of an alkaline earth metal, etc. Seeds may be added. Examples of weak alkali metal salts and/or hydroxides include NaaC.
Os.

NaHCOx, Na-POa, NaOH and KOH are mentioned, and examples of weak acid salts and/or hydroxides of alkaline earth metals include Ca(OH)2°M,!
7(OIi)z −Ba(OH)z ,' Cax(
PO4)2 and Ca(H2PO4)i, among many others. The heat-generating composition for warming feet of the present invention is filled into a bag having air permeability and is put to practical use as a heat-generating bag for warming feet. A breathable bag is a bag in which at least one of the front and back sides of the bag is made of a breathable film. There are no particular restrictions on the material of the film constituting the bag.

The heat-generating composition for foot warming of the present invention uses a conventional water-retaining material and has a considerably smaller volume than the heat-generating composition. The heat-generating composition for foot warming of the present invention is finely aggregated around water-swollen water-absorbing resin, and air can easily diffuse into the heat-generating composition.

In addition, even if the heat-generating bag for foot warming of the present invention is placed under a large amount of wearing pressure, such as when used by placing it on the inner sole of a shoe, water will not seep out to the outside of the heat-generating bag for foot warming. There is little risk of it happening. Furthermore, the heat-generating bag for foot-warming, which is filled with the heat-generating composition for foot-warming of the present invention, has elasticity and is large, unlike those using conventional water-retaining materials, and provides excellent wearing comfort.

Next, the heat generating composition for foot warming of the present invention will be explained in more detail with reference to Examples.

The blending ratio of the exothermic composition of the example was 10F iron powder, 0.5g of salt as an oxidation accelerator, 4g of water, and 1g of active ingredient.Furthermore, as Example 1, a water retaining material with a water absorption capacity of 300 (*1//@
A water-absorbing resin (Sanyo Chemical Co., Ltd. Sunwet IM), which is a starch-acrylic acid embedded graft polymer of water-based resin y)
-300) □ As Example 2, a water-absorbing resin (Jumin Chemical Co., Ltd.) which is a polyvinyl alcohol-acrylic acid ester copolymer with a water-absorbing capacity of 500 (water me/water-absorbing resin I) was used as a water-retaining material. Manufactured by Kososha
Sumikagel S-, 50) was prepared using 0.-2!1 of each.

As Comparative Example 1, 0.5 I of wood flour was used as the water retaining material.As Comparative Example 2, 2.0 g of wood flour was used as the water retaining material.As Comparative Example 3, 0.5.9° of vermiculite was used as the water retaining material.Comparative Example 4 2. Vermiculite is used as a water retention material. O.J.
I prepared each one to be used.

The inner surface of the bag containing the heat generating composition is made of nylon non-woven fabric with a thickness of 5.
A 0μ polyethylene sheet made by Lamine 8Qmm XBO was used.

The exothermic compositions described above were placed in each bag, the opening of each bag was sealed, and the mixture was sufficiently shaken to obtain a heat generating bag.

Thickness 3OIll & Size 300mmX 500i+M
Thickness 6 on the middle part of O Styrofoam, large Kisa 8Qi
l! Place a rubber plate measuring 801 m in diameter, place the above heating bag on top of it, and place a 6 my thick, size 80
Lay one rubber plate of 1+m x 8Qmm on top of each other. In addition,
In this case, the peripheral edge of the heat generating bag and the peripheral edge of the rubber plate must be overlapped so that they substantially match. Then, cover this with two pieces of 100% cotton 100 twin yarn flannel measuring 609mm x 60011III so that the styrofoam board is hidden.

The heat generation characteristics (heat generation temperature reached - heat generation time) as a heat generation bag were measured under the above test conditions. The temperature reached by heat generation was measured using a copper-constancouple thermocouple χ, and the temperature was 20°C.
1. The test was carried out in a constant temperature and humidity room with a humidity of 65%.

The measurement results of the exothermic properties of Examples 1 and 2 and Comparative Examples 1 to 40 are shown in FIG. Further, Table 1 shows the actual pH and volume measurement results of Comparative Examples 1 to 2 and Comparative Examples 1 to 4.

It was found that in Examples 1 and 2, a high exothermic temperature and a long duration were obtained in spite of their small volumes. Examples 1 and 2 were 3°C lower than Comparative Examples 2 and 4, respectively.
It was found that the degree of heat generation was higher than that, and the time that the temperature remained above 40°C was longer than 30 minutes.

Further, in the case of Comparative Examples 1 and 6, the amount of water retaining material was too small relative to the amount of water added, and almost no heat was generated.

Table 1 4, 14f8 leather explanation of drawings
〜Saliva Figure 1 shows Examples 1 and 2 and Comparative Example 11I shellfish 〜4
2 is a drawing showing the heat generation characteristics of each heat generation bag.

Patent applicant: Itsube Suhara, representative of Nippon Bionics Co., Ltd. Chicks 2/Figure r t 4( 3+ ? , /f

Claims (1)

[Claims] In a heat-generating composition for foot warming comprising at least iron powder, an oxidation promoter, water, activated carbon, and a water-retaining material, a water-absorbing resin having a water-absorbing capacity of 30 (Water Go/Water-absorbing resin I) or more is used as the water-retaining material. A heat-generating composition for foot warming characterized by comprising: