JPH0626555B2 - Bag material for the exothermic composition storage bag - Google Patents

Description

TECHNICAL FIELD The present invention relates to a bag material for a bag for storing a heat-generating composition. INDUSTRIAL APPLICABILITY The bag material of the present invention can be used as various bags for storing a heat-generating composition, and can be used as a bag material for body warmers, for example.

[Conventional technology and its problems]

Conventionally, the exothermic composition is stored in a bag and used for various purposes.

For example, a heat-generating composition containing iron powder as a main component is housed in a bag to make a disposable body warmer.

When the exothermic composition is stored in a bag and used as a heating element,
In many cases, the main purpose of the application is to heat this composition to generate heat and utilize the heat. Therefore, the storage bag (heating element) containing the heat generating composition has a stable temperature at the time of heat generation. At the same time, it is desirable that it closely adheres to the object that uses the heat.

For example, in a body warmer, it is desired that the exothermic composition in the bag for storage has a uniform thickness and closely adheres to the object. The better the adhesion in this state, the higher the heating efficiency,
This is also because it feels warm. Further, as will be described later, if the adhesion of the heating element is good, the temperature characteristics are stable. In addition, when a body warmer is used for treatment of rheumatism and the like, it is required that its adhesion be sufficient.

However, in the conventional technique of this type, the adhesiveness is not always sufficient and the temperature characteristic is unstable, and therefore, a satisfactory one has not been obtained.

[Object of the Invention]

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a bag material for a heat-generating composition storage bag that has good adhesion to an object and stable temperature characteristics.

[Means for Solving Problems and Their Actions]

As a result of intensive studies by the present inventors, the above-mentioned object is a bag material for a storage bag that stores an exothermic composition capable of generating heat in the presence of air, and at least a part of the bag material is a breathable micropore. Having a breathability of 0.2 to 1.6 × 10 ⁻⁴
It has been found to be achieved by what is characterized by being in the range of cc · cm ⁻² · sec ⁻¹ · Torr ⁻¹ .

The present invention, as a result of various studies conducted by the present inventors on what kind of structure should be adopted to improve the adhesion to an object as described above, the air permeability of the bag material is important for the adhesion. It was achieved based on the findings of the present inventors.

That is, the above adhesiveness should be sufficiently satisfied by using a sheet having air permeability in the range of 0.2 to 1.6 × 10 ^-4 cc cm ^-2 sec ^-1 Torr ^-1 as at least a part of the bag material. The present invention has been completed by finding out that it can be obtained as a kimono.

When the air permeability exceeds 1.6 × 10 ^-4 cc ・ cm ^-2・ sec ^-1・ Torr ^-1 ,
Adhesion cannot be maintained sufficiently. Adhesion is considered to be that if the gas in the bag, especially oxygen, is absorbed by the exothermic composition and the supply of gas from the air is absorbed, the bag material shrinks and comes into close contact. However, if the air permeability exceeds this range, the gas in the air will easily enter the bag, and as a result, it will expand,
It is considered that the adhesiveness becomes insufficient.

On the other hand, if the air permeability is below 0.2 × 10 ^-4 cc · cm ⁻² · sec ⁻¹ · Torr ⁻¹ , sufficient heat generation cannot be obtained. It is considered that the supply of the component (usually oxygen) required for heat generation into the bag becomes insufficient.

Preferably, the air permeability of the sheet is 0.2 to 1 × 10 ⁻⁴ · cc · cm ⁻² ·
sec ^-1 · Torr ^-1 . Within this range, sufficient adhesion can be obtained when the temperature of the object is about the body temperature of the human body, and thus it is advantageous when applied to an object used in close contact with the human body. However, even if it is out of this range, for example, when the object to be adhered does not maintain a specific body temperature like the human body and is, for example, Styrofoam, sufficient adhesion can be obtained within the range of the present invention. Therefore, it is not limited to this preferable range.

More preferably, the ventilation amount is 0.35 to 0.65 × 10 ⁻⁴ cc · cm ⁻² ·
This is the case of sec ^-1 and Torr ^-1 . In this range, not only the adhesion is generally very good, but also when the object is a human body, the adhesion is good, the heat retention and the sensation are good, and when it is used as a bag material for body warmers, etc. Very advantageous. However, this range also does not limit the present invention as in the above.

In the present invention, the sheet as described above may be provided on at least a part of the bag material. This is because adhesion can be achieved in controlling the air permeability of that portion.

In a preferred embodiment of the present invention, it is possible to adopt a structure in which one side is the above-mentioned sheet and the other side is a non-porous film as a bag material. In this case, the non-porous film is brought into close contact with the skin of the human body, and the surface of the sheet is exposed to air to control ventilation, thereby ensuring the close contact. In such a structure, a poultice member may be provided on the non-perforated film side so that it can be pasted.

The ventilation amount of the sheet is set within the range of the present invention by adopting a sheet having the ventilation amount in such a range and using it, or by adopting an arbitrary sheet and performing printing, resin processing or other means on the sheet. It is also possible to use a material within the range of the present invention by controlling the air flow rate. In any case, the effect of the present invention can be obtained as long as the ventilation amount is within the above range.

When carrying out the present invention, the sheet is preferably flexible. This is because if it is flexible, it is easily bent and the exothermic composition storage bag and the exothermic composition come into close contact with each other. If it is soft, the film itself tends to shrink when the exothermic composition absorbs oxygen, whereby movement of the composition is prevented and adhesion is improved.

In a preferred embodiment of the present invention, the softness of the sheet is such that the softness of the loop Stiffness tester is 2.
Use less than 5g.

Here, Loop Stiffnessteste
r) means that the sample is bent in a loop shape and fixed in a direction where it is difficult to sag due to its own weight (the width direction is aligned vertically), and when the diametrical direction of the loop is crushed, it depends on the strength of the strain at that time. It measures softness and is said to be a measured value that can minimize the influence of the sample's own weight. Here, a loop steph tester No. 581 manufactured by Toyo Seiki Seisakusho Co., Ltd. was used, and measurement was conducted under the condition of a compression speed of 3.5 mm / sec. According to such measurement results, the above range is preferable. However, of course, the present invention is not limited to this. More preferably, 2.0 g or less, and particularly preferably 1.0 g or less of soft material is used.

Next, in another preferred embodiment of the present invention, the sheet having the air-permeable fine pores having a size of 15 μm or less is used. Within this range, preferable adhesion can be obtained.
However, it goes without saying that the present invention is not limited to this. A more preferable size is 5 μm or less.
The size of the fine pores is determined by the maximum bubble pressure method using mercury.

〔Example〕

An embodiment of the present invention will be described below. Of course, the present invention is not limited to the embodiments described below.

In this embodiment, the present invention is applied to a bag material for a disposable body warmer.

A conventional disposable body warmer uses a heat-generating composition containing iron powder wrapped in a breathable bag, and uses the heat generated when the iron powder in the breathable inner bag is oxidized by oxygen in the air during use. It is used for keeping heat, etc., but its temperature characteristics are such that the initial temperature rises sharply and then gradually declines, there is no time when the predetermined temperature is maintained, and therefore it lacks temperature stability and actually Since the exothermic composition is allowed to move freely inside the inner bag when it is used, it is shaken occasionally to stir the exothermic composition to raise the temperature. It assumes free movement within the bag. Therefore, the above-mentioned basic requirement for close contact with the human body cannot be satisfied. On the other hand, the present embodiment can realize a body warmer that solves this problem.

In this example, 10 g of heat-generating material, which is heat-generating composition 3.
Bag material 1 as shown in Fig. 1 in front and back (area is around 70 cm ² )
Then, this is further sealed in an airtight bag 2 (bag membrane air permeability R <5
cc / m ² · day · atm). The above-mentioned sheet 11 is used as the front side membrane of the bag material 1, and in this example, the air permeability R of the front side bag membrane was R = 5 cc / cm ⁻² · sec ⁻¹ · Torr ⁻¹ . For comparison, in the test described below, the test was performed with the air permeability changed as shown in Table 2 below. A material (non-porous film) 12 with R = 0 was used for the back side. At the time of use, the airtight inner bag (bag material) 1 containing the heat-generating composition 3 is taken out as a heat generating element by cleaving the sealed outer bag 2 and brought into close contact (with a cloth or the like sandwiched) on the affected area for the effect of moxibustion. Express.

In the following description of the present embodiment, along with the description of the specific configuration of the embodiment, the advantages of applying the present invention to a body warmer will be described based on various measurement results.

As the exothermic composition, exothermic powder “Aniha Karanya S” (trade name) specially prepared by the applicant was used. This composition is shown in Table 1 together with the composition of the exothermic powder of the commercial disposable warmer.

The water in Anihakalanya S is saline, and its concentration is 14.3% = 14.3 g / d = 2.443 mo /.

Next, the ventilation bag will be described. In this example, the bag material for storing the heat-generating composition of the present invention is used for this ventilation bag. The breathable bag of this example was formed by binding two films, one of which (front) had breathability and the other one (back) of which was non-breathable. The air permeability of this breathable film is within the scope of the present invention,
It exhibits good adhesion. In this example, the air permeability R (cc / cm ² · sec · Torr), the ventilation pore diameter (μm), and the film hardness / toughness (softness) were changed and examined.

The sealed outer bag was made of a stretched polypropylene film coated with polyvinylidene chloride, which was substantially impermeable to air. A heating element composed of a ventilation bag containing the exothermic composition was housed therein to construct the body warmer of this example.

For each sample, data were taken on the maximum temperature Tm, rise time te, and 1 / (Tm-To) as characteristic values. Definitions of various characteristic values are as follows. That is, FIG. 2 shows a general diagram of the temperature characteristic (T-t diagram) of the heating element after the outer bag is cleaved (the time at the time of cleaving is set to t = 0). However, as will be described later, not all samples have stable Tm as shown in the figure, and the sample of the present invention has a large stability.

In FIG. 2, To is room temperature and Tm is the maximum temperature. The rising time te is defined as the time at which the temperature T becomes T = To + 0.632 (Tm-To). Now, if the temperature change is ΔT≡T-To, this condition is Is. In addition, the duration tr is T = T + To + 0.707 (Tm-To) or Is defined as the time. Therefore, the temperature characteristic curve is divided into the following three parts. That is, Is. Here, the effective period is defined as tr-te, but in general, te is sufficiently smaller than tr, so this is approximately equal to tr.

The change in the maximum temperature Tm of the heating element due to the air permeability R of the membrane
Shown in the figure. The breathability range according to the present invention is indicated by reference numeral I in FIG. 3, the above-mentioned preferable breathing range is indicated by II, and the more preferable range is indicated by III.

Next, a graph of temperature characteristics is shown in FIG. The temperature characteristics were measured by either placing the heating element on a Styrofoam stand and measuring the temperature change (without using a towel), or by stacking two folded towels on this and measuring the temperature change as well (towel). use). The temperature measuring terminal is a thermocouple.

The inner bag of a commercially available disposable warmer has a hole with a needle, and its air permeability R is R = ² cc / cm ² · sec · Torr. Temperature characteristic I and R = 0.362 × 10 ^-4 c when using this commercially available bag
FIG. 4 shows the difference in temperature characteristic II with the heating element to which the present invention is applied, which uses a c / sec · Torr film. However, the area S = 7 here
cm x 10 cm, using Aniha Kalanya S15g as the heat generating material,
A towel was used as the measurement condition.

As is clear from FIG. 4, the heating element to which the present invention is applied (characteristics in FIG.
II) and the commercial product (characteristic I in the figure) have essentially different temperature characteristics. The biggest difference is that this heating element has a constant temperature duration, whereas commercial products do not. The temperature stability of this heating element is remarkably excellent.

The air permeability of the sheet used is 11.1 × 10 ^-4 cc / cm ² · sec · Torr
Starting from 5.6, 3.5, 1.7, 1.0,
Fig. 5 shows the change in temperature characteristics when 0.5 × 10 ^-4 cc / cm ² · sec · Torr. This figure shows the heating element
It was measured using 10 g, surface S = 70 cm ² , and no towel. From Fig. 5, R = 11.1, 5.6, 3.5 ×
The temperature characteristics of the three types of 10 ⁻⁴ cc / cm ² · sec · Torr are very similar to the temperature characteristics I (FIG. 4) of the above-mentioned commercially available disposable warmer. (However, in Fig. 4, 4 towels are used for measurement.
It is covered with a sheet, whereas in Fig. 5, a towel is not used).

Now, further reduce the air permeability of the membrane to 1.7 × 10 ^-4 cc / cm ² · sec ・
With Torr, the temperature drops, but the heat generation time increases. However, the stability of temperature is not yet seen.

However, in the case of R = 1.0 × 10 ^-4 cc / cm ² · sec · Tor, the temperature becomes stable, and 0.5 × 10 ^-4 cc / cm ² · sec · To
When it becomes rr, its duration becomes sufficiently long. That is, it is an ideal temperature characteristic.

As a result of various tests conducted on such various samples, it was found that those having an air flow rate within the range of the present invention had good temperature characteristics. Moreover, not only that, but also the heating elements outside the scope of the present invention, the bag was expanded and inflated. In contrast,
In the case of the range of the present invention, the bag contracted in about 30 seconds as if the pressure was reduced, and the heating element became a thin sheet. Detailed observation revealed that even when the bag expanded, it contracted within 30 seconds, but expanded within 2 to 3 minutes.

From the above, the following can be understood. That is, the heating element formed by shrinking the heat generating composition in the bag material may expand or contract depending on the air permeability R of the film of the bag material even if the same material is used in the same amount. However, the temperature characteristics are more stable when stored.

This is presumed to be based on the following actions. That is, if the bag expands, the exothermic composition in the bag becomes motivated. For this reason, the amount of oxygen in contact with the exothermic composition constantly changes, and the temperature characteristic is unstable. This is especially noticeable for dynamic objects such as the human body. (If it contracts, it is in the form of a contact sheet, so it cannot move freely inside the bag of heat-generating powder). Further, as the heat is generated, the water contained in the heating element evaporates and adheres as water droplets inside the film on the upper side of the bag. In the heating element, the amount of water decreases and the reaction rate decreases. Therefore, the temperature decreases. However, when the water droplets attached to the film on the upper part of the bag grow to some extent, due to gravity,
Drop onto exothermic powder. The dropping of water invites a new reaction, the exothermic reaction becomes active, and the temperature rises. There, the water evaporates again. By repeating this, the temperature is not stable and rises and falls. This is not the case with a contact sheet having a small R.

As described above, when the air permeability R of the film forming the hot moxibustion agent is large, the bag of the hot moxibustion agent is inflated and the temperature is unstable. It can be seen that it exhibits excellent temperature characteristics.

In order to specifically confirm the effect of the present invention, in the present example, a membrane whose air permeability was changed as shown in Table 2 was used.
Sample Nos. 1 to 18 having the structure shown in the figure were prepared, and the data on the maximum temperature Tm and others were taken. The air permeability is obtained by measuring the air flow rate itself in a substantial area.

As understood from Table 2, sample No. 5 to which the present invention is applied
Nos. 13 to 13 are all good in terms of maximum temperature Tm and duration tr, and Sample Nos. 9 to 13 are particularly preferable.
The maximum temperatures Tm of O.9 to 11 are the most appropriate, and the duration is sufficient, showing the best results.

In addition, the four samples of sample Nos. 1, 5, 6, and 8 use the membranes that originally have the air permeability shown in the table, and the other samples are shown as the membranes by controlling the air permeability by printing. It was carried out by using a material having air permeability.

[Effects of the Invention] As described above, according to the present invention, a bag material for a bag for accommodating an exothermic composition, which has good adhesion and can stabilize temperature characteristics, can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing the structure of an embodiment in which the present invention is applied to a body warmer. 2 to 5 are views for explaining the effect of the present invention. 1 ... Bag material, 11 ... Sheet with breathable micropores, 12 ...
... anhydrous film, 3 ... exothermic composition.

Claims (3)

[Claims] 1. A bag material for a storage bag that stores a heat-generating composition capable of generating heat in the presence of air, wherein at least a part of the bag material is a sheet having air-permeable micropores. A bag material for a heat-generating composition storage bag, which has a breathability of 0.2 to 1.6 × 10 ^-4 cc · cm ⁻² · sec ⁻¹ · Torr ⁻¹ . 2. A bag material for a heat-generating composition-containing bag according to claim 1, wherein the sheet has a softness of 2.5 g or less in a loop stiffener tester. 3. The sheet has breathable micropores having a size of 15
The bag material for the heat-generating composition-containing bag according to claim 1 or 2, wherein the bag material has a value of μ or less.