JP2021109939A - Cold storage material - Google Patents

Abstract

To provide a cold storage material suitable for storage and refrigeration of a liquid medicine or food.SOLUTION: There is provided a cold storage material which comprises a tera-n-butylammonium ion represented by the chemical formula: [(CH3CH2CH2CH2)4 N]+, an ammonium ion represented by the chemical formula: NH4+, a chloride ion and water. The molar ratio represented by [NH4+]/[TBA+] is 1.5 or more. The molar ratio represented by [Cl-]/[X-] is 0.95 or more and 1 or less. The cold storage material has a melting point of 2°C or more and 8°C or less and has a heat of fusion of 150 J/g or more in the relevant temperature range.SELECTED DRAWING: Figure 20

Description

The present disclosure relates to a cold storage material.

Patent Document 1 discloses a cold insulation composition containing water, a quaternary ammonium salt, and an inorganic salt.

Patent Document 2 discloses a heat storage device. Patent Document 2 also discloses that the clathrate hydrate of tetrabutylammonium chloride has a melting point of approximately 15 degrees Celsius.

JP-A-2017-179298 Japanese Unexamined Patent Publication No. 2018-059676

Mohamed Rady et. Al. "A Comparative Study of Phase Changing Characteristics of Granular Phase Change Materials Using DSC and T-History Methods", Tech Science Press FDMP, vol.6, no.2, pp.137-152, 2010

An object of the present disclosure is to provide a cold storage material suitable for storage and refrigeration of liquid medicines or foods.

The cold storage material of the present disclosure is
Chemical formula _{[(CH 3 CH 2 CH 2} CH 2) 4 N] + by represented by tetra -n- butylammonium ion Formula _NH ^{4 +} with ammonium ions chloride ion represented, and contains water,
here,
The molar ratio represented by [NH ₄ ⁺ ] / [TBA ⁺ ] is 1.5 or more.
here,
[NH ₄ ⁺ ] represents the ammonium ion molar concentration represented by the chemical formula NH ₄ ^{+ , and [TBA +} ] is represented by the chemical formula [(CH ₃ CH ₂ CH ₂ CH ₂ ) ₄ N] ^+. Represents the molar concentration of tetra-n-butylammonium ions.
The molar ratio represented by [Cl ⁻ ] / [X ⁻ ] is 0.95 or more and 1 or less.
here,
[Cl ⁻ ] represents the molar concentration of the chloride ion contained in the cold storage material, and [X ⁻ ] represents the molar concentration of the halide ion contained in the cold storage material.
The halide ion contains the chloride ion and contains the chloride ion.
The cold storage material has a melting point of 2 degrees Celsius or more and 8 degrees Celsius or less, and the cold storage material has a heat of fusion of 150 joules / gram or more in the range of 2 degrees Celsius or more and 8 degrees Celsius or less.

The present disclosure provides cold storage materials suitable for storage and refrigeration of liquid pharmaceuticals or foods.

FIG. 1 is a graph showing the characteristics of the cold storage material during cold storage. FIG. 2 is a graph showing the characteristics of the cold storage material at the time of cooling. FIG. 3 is a graph showing the results of differential scanning calorimetry in Example 1. FIG. 4 is a graph showing the results of differential scanning calorimetry in Example 2. FIG. 5 is a graph showing the results of differential scanning calorimetry in Example 3. FIG. 6 is a graph showing the results of differential scanning calorimetry in Example 4. FIG. 7 is a graph showing the results of differential scanning calorimetry in Comparative Example 1. FIG. 8 is a graph showing the results of differential scanning calorimetry in Comparative Example 2. FIG. 9 is a graph showing the results of differential scanning calorimetry in Example 5. FIG. 10 is a graph showing the results of differential scanning calorimetry in Example 6. FIG. 11 is a graph showing the results of differential scanning calorimetry in Example 7. FIG. 12 is a graph showing the results of differential scanning calorimetry in Comparative Example 3. FIG. 13 is a graph showing the results of differential scanning calorimetry in Comparative Example 4. FIG. 14 is a graph showing the results of differential scanning calorimetry in Example 8. FIG. 15 is a graph showing the results of differential scanning calorimetry in Example 9. FIG. 16 is a graph showing the results of differential scanning calorimetry in Example 10. FIG. 17 is a graph showing the results of differential scanning calorimetry in Comparative Example 5. FIG. 18 is a graph showing the results of differential scanning calorimetry in Comparative Example 6. FIG. 19 is a graph showing the results of differential scanning calorimetry in Comparative Example 7. FIG. 20 shows a schematic view of the cooler box 100 according to the second embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment)
FIG. 1 is a graph showing the characteristics of the cold storage material during cooling. In FIG. 1, the horizontal axis and the vertical axis indicate time and temperature, respectively.

The cold storage material according to the first embodiment is cooled. See section A included in FIG. Unlike the case of general liquids, as is well known in the technical field of cold storage materials, even if the temperature of the cold storage material reaches its melting point due to cooling of the cold storage material, the cold storage material does not solidify and is excessive. It will be in a cooled state. See section B included in FIG. In the supercooled state, the cold storage material is a liquid.

The cold storage material then begins to spontaneously crystallize. With crystallization, the cold storage material releases heat of crystallization that is approximately equal to the latent heat. As a result, the temperature of the cold storage material begins to rise. See section C included in FIG. In the present specification, the temperature at which the cold storage material starts to crystallize spontaneously is referred to as "crystallization temperature".

ΔT represents the difference between the melting point and the crystallization temperature of the cold storage material. ΔT may also be referred to as “supercooling degree”. Due to the crystallization of the cold storage material in the supercooled state, the cold storage material becomes semi-class hydrate (see, for example, Patent Document 2). Here, the clathrate hydrate refers to a crystal formed by water molecules forming a cage-like crystal by hydrogen bonding and wrapping a substance other than water in the crystal. Semi-class hydrate refers to crystals formed by guest molecules participating in the hydrogen bond network of water molecules. The concentration at which water molecules and guest molecules form hydrates in just proportion is called the harmonic concentration. In general, hydrates are often used near the harmonized concentration.

After the release of the heat of crystallization of the cold storage material is completed with the completion of crystallization, the temperature of the cold storage material gradually decreases so as to be equal to the ambient temperature. See section D included in FIG.

The crystallization temperature is lower than the melting point of the cold storage material. The melting point of the cold storage material can be measured using a differential scanning calorimeter (which may also be referred to as "DSC"), as is well known in the art of cold storage materials.

FIG. 2 is a graph showing the characteristics of the cold storage material at the time of heating. In FIG. 2, the horizontal axis and the vertical axis indicate time and temperature, respectively. During section E, the temperature of the cold storage material is maintained below the crystallization temperature. For example, the temperature inside the cooler box is set below the crystallization temperature so that the temperature of the cold storage material placed in the cooler box is kept below the crystallization temperature while the cooler box lid is closed. ing.

Next, the cold storage material is gradually heated. See section F included in FIG. For example, when the cooler box lid is opened (or when the lid is opened to contain food) at the end of section E (ie, the beginning of section F), the temperature inside the cooler box gradually increases.

When the temperature of the cold storage material reaches the melting point of the cold storage material, the temperature of the cold storage material is maintained near the melting point of the cold storage material. See section G included in FIG. In the unlikely event that there is no cold storage material, the temperature inside the cooler box rises continuously as shown in section Z included in FIG. On the other hand, when there is a cold storage material, the temperature inside the cooler box is maintained near the melting point of the cold storage material for a certain period of the section G. In this way, the cold storage material exerts a cold storage effect. At the end of section G, the crystals of the cold storage material melt and disappear. As a result, the cold storage material is liquefied.

After that, the temperature of the liquefied cold storage material rises so as to be equal to the ambient temperature. See section H included in FIG.

The cold storage material can be cooled and reused.

The following conditions (I) and (II) must be met for a cold storage material that is suitably used for a cooler box that can have liquid medicines or foods inside.
Condition (I) The cold storage material has a melting point of 2 degrees Celsius or more and 8 degrees Celsius or less. As an example, the cold storage material has a melting point of 3 degrees Celsius or more and 7 degrees Celsius or less.
Condition (II) The cold storage material has a large amount of heat of fusion of 150 joules / gram or more (preferably 160 joules / gram or more) in the range of 2 degrees Celsius or more and 8 degrees Celsius or less.

The reason for condition (I) is that for the storage of liquid medicines and foods, the inside of the cooler box should be maintained at approximately 2 degrees Celsius or higher and 8 degrees Celsius or lower. In the unlikely event that the temperature inside the cooler box is maintained below 0 degrees Celsius, the water contained inside the liquid medicine and food will change to ice, and the liquid medicine and food may deteriorate. On the other hand, if the temperature inside the cooler box is maintained at a temperature exceeding 8 degrees Celsius, the cooler box is not functioning.

The reason for condition (II) is to increase the efficiency of the cold storage material. Needless to say, unlike a refrigerator, a cooler box can be carried around. Therefore, it is desirable that the weight of the cooler box is small. The weight of the cooler box can be reduced by the highly efficient cold storage material. In other words, a cold storage material having a small heat of fusion of less than 150 joules / gram in the range of 2 degrees Celsius or more and 8 degrees Celsius or less increases the weight of the cooler box. Therefore, such cold storage materials are not suitable for cooler boxes.

In this art, the amount of heat of fusion is also referred to as the amount of latent heat.

To prevent confusion, "Kelvin" is used herein for the degree of supercooling ΔT. For example, the present inventor describes it as "the degree of supercooling ΔT is n Kelvin or less". Needless to say, n is a real number. The explanation "supercooling degree ΔT ≦ 5 Kelvin" means that the difference between the crystallization temperature and the melting point of the cold storage material is 5 Kelvin or less. On the other hand, in the present specification, "Celsius" is used for temperature. For example, the inventor states that "the crystallization temperature is 5 degrees Celsius" (ie, 5 degrees Celsius).

The cold storage material according to the first embodiment is
Chemical formula _{[(CH 3 CH 2 CH 2} CH 2) 4 N] + by represented by tetra -n- butylammonium ion Formula _NH ^{4 +} with ammonium ions chloride ion represented, and contains water.

In the cold storage material according to the first embodiment, the _{molar ratio represented by [NH 4} ⁺ ] / [TBA ⁺ ] is 1.5 or more.
here,
[NH ₄ ⁺ ] represents the ammonium ion molar concentration represented by the chemical formula NH ₄ ^{+ , and [TBA +} ] represents the tetra represented by the chemical formula [(CH ₃ CH ₂ CH ₂ CH ₂ ) ₄ N] ^+. Represents the molar concentration of -n-butylammonium ion.

In the unlikely event _{that the molar ratio represented by [NH 4} ⁺ ] / [TBA ⁺ ] is less than 1.5, it will be 2 degrees Celsius, as demonstrated in Comparative Examples 1 and 2 described below. The amount of heat of fusion in the range of 8 degrees Celsius or less is less than 150 joules / gram.

The molar ratio represented by [NH ₄ ⁺ ] / [TBA ⁺ ] can be 3 or less.

In the cold storage material according to the first embodiment, the ^{molar ratio represented by [Cl −} ] / [X ⁻ ] is 0.95 or more and 1 or less.
here,
[Cl ⁻ ] represents the molar concentration of chloride ions contained in the cold storage material, and [X ⁻ ] represents the molar concentration of the halide ion contained in the cold storage material.

Similar to the well-known chemical definition of "halogen", halide ions include chloride ions. In other words, the cold storage material according to the first embodiment always contains chloride ions as halide ions. On the other hand, the cold storage material according to the first embodiment may contain at least one selected from fluoride ions, bromide ions, and iodide ions as the halide ions.

In the cold storage material according to the first embodiment, the ^{molar ratio represented by [Cl −} ] / [X ⁻ ] is 0.95 or more and 1 or less.

In the unlikely event ^{that the molar ratio represented by [Cl −} ] / [X ⁻ ] is less than 0.95, as will be demonstrated in Comparative Examples 3 to 7 described later, 2 degrees Celsius or more and 8 degrees Celsius The amount of heat of fusion in the range below degrees is less than 150 joules / gram.

Hereinafter, [X ⁻ ], that is, the molar concentration of the halide ion contained in the cold storage material will be described. In the present specification, the following formula 1 is satisfied.
(Number 1)
[X ⁻ ] = [Cl ⁻ ] + [F ⁻ ] + [Br ⁻ ] + [I ⁻ ]
Here, [F ⁻ ], [Br ⁻ ], and [I ⁻ ] represent the molar concentrations of fluoride ions, bromide ions, and iodide ions contained in the cold storage material, respectively.

Since iodide ions can inhibit the formation of semi-class hydrates, it is desirable that the cold storage material according to the first embodiment does not contain iodide ions. Therefore, the cold storage material according to the first embodiment may contain at least one selected from fluoride ions and bromide ions as the halide ions. In this case, the following mathematical formula 2 is satisfied.
(Number 2)
[X ⁻ ] = [Cl ⁻ ] + [F ⁻ ] + [Br ⁻ ]

However, as is clear when comparing Examples 1 to 4 described later with Examples 5 to 10, the fluoride ion and the bromide ion have a heat of fusion in the range of 2 degrees Celsius or more and 8 degrees Celsius or less. Can be reduced. Therefore, it is desirable that the cold storage material according to the first embodiment contains chloride ions, but does not contain any of fluoride ions, bromide ions, and iodide ions. Therefore, it is desirable that the following formula 3 is satisfied (Equation 3).
[X ⁻ ] = [Cl ⁻ ]

When Equation 3 is satisfied, the ^{molar ratio represented by [Cl −} ] / [X ⁻ ] is equal to 1. Needless to say, [Cl ⁻ ] is not excluded from ^{[X −] in the present specification.} In other words, in the present specification, [Cl ⁻ ] is always included in ^{[X −].}

In the cold storage material according to the first embodiment, it is desirable that the mole fraction of water is 0.7 or more and 0.99 or less. That is, it is desirable that the molar ratio of water to the entire cold storage material is 0.7 or more and 0.99 or less. When the molar fraction of water is less than 0.7, excess TBAC and NH 4 because it contains _Cl, heat of fusion per weight may occur the disadvantage of a decrease. On the other hand, when the mole fraction of water exceeds 0.99, the melting point is lowered, which may cause a drawback that the cold storage material does not function in a desired temperature range.

Ammonium molar concentration of halide ions comprising chloride ions, which are the chemical formula _{[(CH 3 CH 2 CH 2} CH 2) 4 N] + represented by tetra -n- butyl ammonium ions and formula _NH ^{4 +} are represented by It should be equal to the sum of the molar concentrations of the ions. Here, hydrogen ions and hydroxide ions contained in the aqueous solution are not considered. Desirably, the cold storage material according to the first embodiment is neutral.

The cold storage material according to the first embodiment has a melting point of 2 degrees Celsius or more and 8 degrees Celsius or less, and has a heat of fusion of 150 joules / gram or more in the range of 2 degrees Celsius or more and 8 degrees Celsius or less. _{CH 3 CH 2 CH 2 CH 2} ) 4 N] tetra -n- butylammonium ion represented by ^+, the formula _NH ^{4 +} with ammonium ion represented, contain chloride ions, and additives other than water You may.

Examples of additives are supercooling inhibitors, thickeners, and preservatives.

The cold storage material according to the first embodiment does not have to contain additives. In other words, the cold storage material according to the first embodiment is a tetra-n-butylammonium ion represented by _{the chemical formula [(CH 3} CH ₂ CH ₂ CH ₂ ) ₄ N] ^{+, and} an ammonium ion represented by the _{chemical formula NH 4} ^+. , Chloride ion, and water.

The cold storage material according to the first embodiment can be produced as follows.
First, tetra-n-butylammonium chloride represented by the chemical formula [(CH ₃ CH ₂ CH ₂ CH ₂ ) ₄ N] ⁺ Cl ⁻ is dissolved in water to obtain an aqueous solution.
Next, ammonium chloride represented by the chemical formula NH ₄ Cl is added to the aqueous solution. In this way, the cold storage material according to the first embodiment is obtained.

(Second Embodiment)
Hereinafter, the cooler box according to the second embodiment will be described.

FIG. 20 shows a schematic view of the cooler box 100 according to the second embodiment.

The cooler box 100 includes a heat insulating box 101 and a heat insulating lid 102 including a bottom (not shown) and side surfaces.

According to the first embodiment, at least one interior selected from the group consisting of the inner bottom surface of the heat insulating box 101, the inner side surface of the heat insulating box 101, and the inner surface (that is, the lower surface) of the heat insulating lid 102. A cold storage material is provided. In FIG. 20, a cold storage material pack 110 containing the cold storage material according to the first embodiment is provided so as to be in contact with each of the four inner side surfaces of the heat insulating box 101 having a rectangular parallelepiped shape.

The cold storage material according to the first embodiment may be provided in at least one selected from the group consisting of the inside of the bottom of the heat insulating box 101, the inside of the side surface of the heat insulating box 101, and the inside of the heat insulating lid 102. The cold storage material according to the first embodiment is the space inside the cooler box 100 (that is, the space formed by the inner bottom surface of the heat insulating box 101, the inner side surface of the heat insulating box 101, and the inner surface of the heat insulating lid 102). The cold storage material according to the first embodiment may be contained therein so as to be placed in the form of a cold storage material pack 110.

The cold storage material according to the first embodiment may be provided inside at least one selected from the group consisting of the side surface of the heat insulating box, the heat insulating lid of the heat insulating box, and the heat insulating box itself. In this case as well, the cold storage material according to the first embodiment may be provided in the form of the cold storage material pack 110.

It is desirable that at least one selected from the group consisting of pharmaceuticals and foods be placed inside the heat insulating box 101. In FIG. 20, the drug 120 is placed inside the heat insulating box 101. An example of a drug is a liquid drug. An example of a liquid drug is a vaccine. When a vaccine is carried, it is required to be stored at 2 degrees Celsius or more and 8 degrees Celsius or less in order to maintain its quality. In the cooler box according to the second embodiment, the cold storage material according to the first embodiment has a melting point of 2 degrees Celsius or more and 8 degrees Celsius or less, and is as large as 150 joules / gram or more in the range of 2 degrees Celsius or more and 8 degrees Celsius or less. Since it has a calorific value for melting, it is suitable for carrying a vaccine.

(Example)
The present invention will be described in more detail with reference to the following examples.

(Definition of terms)
The term "TBAC" means tetra-n-butylammonium chloride represented by the chemical formula [(CH ₃ CH ₂ CH ₂ CH ₂ ) ₄ N] ⁺ Cl ^−. TBAC is a solid and can be purchased from Tokyo Chemical Industry Co., Ltd.
The term "TBAF" means tetra-n-butylammonium fluoride represented by the chemical formula [(CH ₃ CH ₂ CH ₂ CH ₂ ) ₄ N] ⁺ F ^−. TBAF can be purchased from Tokyo Chemical Industry Co., Ltd. in the form of a 75% aqueous solution.

(Example 1)
(Manufacturing method of cold storage material)
First, the reagents shown in Table 1 below were added to a screw tube with a capacity of 110 ml.
(Table 1)
35 grams of TBAC (equivalent to 126 mmol)
65 grams of water (equivalent to 3610 mmol)

The reagent was thoroughly stirred in the screw tube to give a mixture (100 grams). The screw tube was a glass tube with a screwed lid.

The mixture (containing 8.81 grams and 11.1 mmol TBAC) was removed from a screw tube with a capacity of 110 ml. The mixture (8.81 grams) was then fed into a screw tube with a capacity of 60 milliliters.

The reagents shown in Table 2 below were then added to the screw tube having a capacity of 60 ml.
(Table 2)
Ammonium chloride (NH ₄ Cl, purchased from Fuji Film Wako Pure Chemical Industries, Ltd.) 1.19 grams (equivalent to 22.2 mmol)

The reagent was well stirred in the screw tube. In this way, the cold storage material (10 grams) according to Example 1 was obtained. In Example 1, _{the molar ratio of [NH 4} ⁺ ] / [TBA ⁺ ] was 2 (= 22.2 / 11.1). In Example 1, since the halide ion consists only of chloride ion, the value of ^{[Cl −} ] / [X ^{−] was 1.}

(Measurement of differential scanning calorimetry)
The cold storage material (2 mg) according to Example 1 was supplied to a container (obtained from PerkinElmer, trade name: 02192005). The container was incorporated into a differential scanning calorimeter (obtained from PerkinElmer, trade name: DSC-8500). The cold storage material contained inside the container was cooled from room temperature to -30 degrees Celsius at a rate of 1 degree Celsius / minute and crystallized. Next, the cold storage material was allowed to stand at -30 degrees Celsius for 5 minutes.

The crystallized cold storage material was heated from -30 degrees Celsius to 30 degrees Celsius at a rate of 1 degree Celsius / minute. In this way, the crystallized cold storage material was melted.

The differential scanning calorimetry outputs heat flow (unit: watts) while the crystallized cold storage material is being heated from -30 degrees Celsius to 30 degrees Celsius at a rate of 1 degree Celsius / minute as described above. did.

The melting point of the cold storage material according to Example 1 was identified based on the endothermic peak output from the DSC while the cold storage material according to Example 1 was melting. As a result, the melting point of the cold storage material according to Example 1 was 4.1 degrees Celsius. The melting point of the cold storage material is equal to the temperature at which the peak (ie, the endothermic peak) is located in the graph showing the result of the differential scanning calorimetry.

FIG. 3 is a graph showing the results of differential scanning calorimetry in Example 1.
The normalized heat flow was calculated according to the following formula. See also FIG. 2 of Non-Patent Document 1.
(Standardized heat flow, unit: W / g) = (heat flow) / (weight of cold storage material, that is, 2 milligrams)

Based on FIG. 3, the integrated value of the differential scanning calorimetry in the range of 2 degrees Celsius to 8 degrees Celsius was calculated as the amount of heat of fusion in the range of 2 degrees Celsius to 8 degrees Celsius. As a result, the cold storage material according to Example 1 had a heat of fusion of 184 joules / gram in the range of 2 degrees Celsius or more and 8 degrees Celsius or less. As is clear from FIG. 3, the cold storage material in Example 1 had a melting point of about 4.1 degrees Celsius.

(Example 2)
In Example 2, the same experiment as in Example 1 was carried out except that the amount of ammonium chloride added was 16.6 mmol. In Example 2, _{the molar ratio of [NH 4} ⁺ ] / [TBA ⁺ ] was 1.5 (= 16.6 / 11.1).
FIG. 4 is a graph showing the results of differential scanning calorimetry in Example 2.

(Example 3)
In Example 3, the same experiment as in Example 1 was carried out except that the amount of ammonium chloride added was 27.7 mmol. In Example 3, _{the molar ratio of [NH 4} ⁺ ] / [TBA ⁺ ] was 2.5 (= 27.7 / 11.1).
FIG. 5 is a graph showing the results of differential scanning calorimetry in Example 3.

(Example 4)
In Example 4, the same experiment as in Example 1 was carried out except that the amount of ammonium chloride added was 33.3 mmol. In Example 4, _{the molar ratio of [NH 4} ⁺ ] / [TBA ⁺ ] was 3 (= 33.3 / 11.1).
FIG. 6 is a graph showing the results of differential scanning calorimetry in Example 4.

(Comparative Example 1)
In Comparative Example 1, the same experiment as in Example 1 was carried out except that the amount of ammonium chloride added was 5.5 mmol. In Comparative Example 1, _{the molar ratio of [NH 4} ⁺ ] / [TBA ⁺ ] was 0.5 (= 5.5 / 11.1).
FIG. 7 is a graph showing the results of differential scanning calorimetry in Comparative Example 1.

(Comparative Example 2)
In Comparative Example 2, the same experiment as in Example 1 was carried out except that the amount of ammonium chloride added was 11.1 mmol. In Comparative Example 2, _{the molar ratio of [NH 4} ⁺ ] / [TBA ⁺ ] was 1 (= 11.1 / 11.1).
FIG. 8 is a graph showing the results of differential scanning calorimetry in Comparative Example 2.

(Example 5)
In a screw tube (capacity: 60 ml) containing the latent heat storage material (9.70 g) obtained in Example 2, TBAF (75 wt% aqueous solution, 0.53 g, that is, 1.
Tokyo Chemical Industry Co., Ltd., containing 53 mmol TBAF, water (0.65 g, equal to 36.4 mmol), and ammonium chloride (NH ₄ Cl, 0.12 g, equal to 2.29 mmol, The same experiment as in Example 2 was carried out except that a latent heat storage material was obtained by adding Fuji Film Wako Pure Chemical Industries, Ltd.).
FIG. 9 is a graph showing the results of differential scanning calorimetry in Example 5.

(Example 6)
A screw tube (capacity: 60 ml) containing the latent heat storage material (10.29 g) obtained in Example 3 contains TBAF (75 wt% aqueous solution, 0.78 g, that is, 2.25 mmol of TBAF). , Tokyo Kasei Kogyo Co., Ltd.), water (0.96 grams, ie equal to 53.6 mmol), and ammonium chloride (NH ₄ Cl, 0.30 grams, equal to 5.61 mmol, Fuji Film The same experiment as in Example 3 was carried out except that a latent heat storage material was obtained by adding (manufactured by Wako Pure Chemical Industries, Ltd.).
FIG. 10 is a graph showing the results of differential scanning calorimetry in Example 6.

(Example 7)
A screw tube (capacity: 60 ml) containing the latent heat storage material (10.60 g) obtained in Example 4 contains TBAF (75 wt% aqueous solution, 0.76 g, that is, 2.18 mmol TBAF). , Tokyo Kasei Kogyo Co., Ltd.), water (0.94 grams, equal to 52.1 mmol), and ammonium chloride (NH ₄ Cl, 0.35 grams, equal to 6.53 mmol), Fuji Film The same experiment as in Example 4 was carried out except that a latent heat storage material was obtained by adding (manufactured by Wako Pure Chemical Industries, Ltd.).
FIG. 11 is a graph showing the results of differential scanning calorimetry in Example 7.

(Comparative Example 3)
A screw tube (capacity: 60 ml) containing the cold storage material (9.70 g) obtained in Example 2 contains TBAF (75 wt% aqueous solution, 1.24 g, ie 3.55 mmol of TBAF). Made by Tokyo Kasei Kogyo Co., Ltd.), water (1.52 grams, that is, equal to 84.6 mmol), and ammonium chloride (NH ₄ Cl, 0.29 g, that is, equal to 5.32 mmol), Fuji Film Sum The same experiment as in Example 2 was carried out except that a cold storage material was obtained by adding (manufactured by Kojunyaku Co., Ltd.).
FIG. 12 is a graph showing the results of differential scanning calorimetry in Comparative Example 3.

(Comparative Example 4)
A screw tube (capacity: 60 ml) containing the cold storage material (10.29 g) obtained in Example 3 contains TBAF (75 wt% aqueous solution, 2.02 g, that is, 5.81 mmol of TBAF). Made by Tokyo Kasei Kogyo Co., Ltd.), water (2.49 grams, equal to 138.4 mmol), and ammonium chloride (NH ₄ Cl, 0.78 grams, equal to 14.5 mmol), Fuji Film Sum The same experiment as in Example 3 was carried out except that a cold storage material was obtained by adding (manufactured by Kojunyaku Co., Ltd.).
FIG. 13 is a graph showing the results of differential scanning calorimetry in Comparative Example 4.

(Example 8)
A screw tube (capacity: 60 ml) containing the cold storage material (9.70 g) obtained in Example 2 was charged with a mixture (0.75 g, that is, containing 0.94 mmol TBAC) and bromide. Same as in Example 2 except that a cold storage material was obtained by adding ammonium (NH ₄ Br, 0.14 g, that is, equal to 1.41 mmol, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.). Experiment was conducted.
FIG. 14 is a graph showing the results of differential scanning calorimetry in Example 8.

(Example 9)
In a screw tube (capacity: 60 ml) containing the cold storage material (10.29 g) obtained in Example 3, a mixed solution (containing 0.59 g, that is, 0.74 mmol of TBAC) and bromide. Same as Example 3 except that a cold storage material was obtained by adding ammonium (NH ₄ Br, 0.18 g, that is, equal to 1.85 mmol, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.). Experiment was conducted.
FIG. 15 is a graph showing the results of differential scanning calorimetry in Example 9.

(Example 10)
A screw tube (capacity: 60 ml) containing the cold storage material (10.60 g) obtained in Example 4 was provided with a mixture (0.55 g, i.e. containing 0.69 mmol TBAC) and bromide. Same as Example 4 except that a cold storage material was obtained by adding ammonium (NH ₄ Br, 0.20 g, that is, equal to 2.07 mmol, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.). Experiment was conducted.
FIG. 16 is a graph showing the results of differential scanning calorimetry in Example 10.

(Comparative Example 5)
A screw tube (capacity: 60 ml) containing the cold storage material (9.70 g) obtained in Example 2 was charged with a mixture (1.64 g, that is, containing 2.06 mmol TBAC) and bromide. Same as in Example 2 except that a cold storage material was obtained by adding ammonium (NH ₄ Br, 0.30 g, that is, equal to 3.09 mmol, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.). Experiment was conducted.
FIG. 17 is a graph showing the results of differential scanning calorimetry in Comparative Example 5.

(Comparative Example 6)
In a screw tube (capacity: 60 ml) containing the cold storage material (10.29 g) obtained in Example 3, a mixed solution (2.09 g, that is, containing 2.64 mmol of TBAC) and bromide. Similar to Example 3 except that a cold storage material was obtained by adding ammonium (NH ₄ Br, 0.65 g, that is, equal to 6.59 mmol, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.). Experiment was conducted.
FIG. 18 is a graph showing the results of differential scanning calorimetry in Comparative Example 6.

(Comparative Example 7)
In a screw tube (capacity: 60 ml) containing the cold storage material (10.60 g) obtained in Example 4, a mixed solution (containing 2.27 g, that is, 2.86 mmol TBAC) and bromide. Same as Example 4 except that a cold storage material was obtained by adding ammonium (NH ₄ Br, 0.84 g, that is, equivalent to 8.56 mmol, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.). Experiment was conducted.
FIG. 19 is a graph showing the results of differential scanning calorimetry in Comparative Example 7.

Table 3 below shows the results of Examples 1 to 10 and Comparative Examples 1 to 7.

As is clear from comparing Examples 1 to 10 with Comparative Examples 1 to 7, the cold storage material satisfying the following conditions (A) to (C) is 2 degrees Celsius or more and 8 degrees Celsius or less. It has a melting point and a large amount of heat of fusion of 161 joules / gram or more in the range of 2 degrees Celsius or more and 8 degrees Celsius or less.
Condition (A) the cold storage material, chemical formula _{[(CH 3 CH 2 CH 2} CH 2) 4 N] + by represented by tetra -n- butylammonium ion, formula _NH ^{4 +} with ammonium represented ions, and chloride It must be an aqueous solution containing ions.
Condition (B) The _{molar ratio represented by [NH 4} ⁺ ] / [TBA ⁺ ] is 1.5 or more.
Condition (C) The ^{molar ratio represented by [Cl −} ] / [X ⁻ ] is 0.95 or more and 1 or less.

In the unlikely event that condition (B) is not satisfied, in other words, if the _{molar ratio represented by [NH 4} ⁺ ] / [TBA ⁺ ] is less than 1.5, it is clear from Comparative Examples 1 to 7. like,
The amount of heat of fusion in the range of 2 degrees Celsius or more and 8 degrees Celsius or less is 145 joules / gram or less.

If the condition (C) is not satisfied, in other words, if the ^{molar ratio represented by [Cl −} ] / [X ⁻ ] is less than 0.95, it will be clear from Comparative Examples 3 to 7. In addition, the amount of heat of fusion in the range of 2 degrees Celsius or more and 8 degrees Celsius or less is less than 150 joules / gram.

_{[NH 4} ⁺ ] / [as will be apparent when Examples 2, 3 and 4 are compared with Examples 5 and 8, Example 6 and Example 9, and Examples 7 and 10, respectively. When the ^{molar ratio represented by [TBA +} ] is a constant value, the amount of heat of fusion in the range of 2 degrees Celsius or more and 8 degrees Celsius or less is greater when [Cl ⁻ ] / [X ⁻ ] is equal to 1. Higher than when [Cl ⁻ ] / [X ⁻ ] is less than 1. Therefore, it is desirable that the cold storage material contains neither fluoride ions nor bromide ions. In other words, it is desirable that the halide ion contained in the cold storage material consists only of chloride ion. In this case, the amount of heat of fusion in the range of 2 degrees Celsius or more and 8 degrees Celsius or less is 178 joules / gram or more.

The cold storage material according to the present disclosure can be used for a cooler box suitable for storing and refrigerating liquid medicines or foods.

100 Cooler box 101 Insulation box 102 Insulation lid 110 Cold storage pack 120 Pharmaceuticals

Claims (9)

It ’s a cold storage material,
Chemical formula _{[(CH 3 CH 2 CH 2} CH 2) 4 N] + by represented by tetra -n- butylammonium ion Formula _NH ^{4 +} with ammonium ions chloride ion represented, and contains water,
here,
The molar ratio represented by [NH ₄ ⁺ ] / [TBA ⁺ ] is 1.5 or more.
here,
[NH ₄ ⁺ ] represents the ammonium ion molar concentration represented by the chemical formula NH ₄ ^{+ , and [TBA +} ] is represented by the chemical formula [(CH ₃ CH ₂ CH ₂ CH ₂ ) ₄ N] ^+. Represents the molar concentration of tetra-n-butylammonium ions.
The molar ratio represented by [Cl ⁻ ] / [X ⁻ ] is 0.95 or more and 1 or less.
here,
[Cl ⁻ ] represents the molar concentration of the chloride ion contained in the cold storage material, and [X ⁻ ] represents the molar concentration of the halide ion contained in the cold storage material.
The halide ion contains the chloride ion and contains the chloride ion.
The cold storage material has a melting point of 2 degrees Celsius or more and 8 degrees Celsius or less, and the cold storage material has a heat of fusion of 150 joules / gram or more in the range of 2 degrees Celsius or more and 8 degrees Celsius or less.
Cold storage material. The cold storage material according to claim 1.
The molar ratio represented by [NH ₄ ⁺ ] / [TBA ⁺ ] is 3 or less.
Cold storage material. The cold storage material according to claim 1.
A cold storage material in which the molar ratio represented by [Cl ⁻ ] / [X ⁻ ] is 1, and the halide ion is composed of the chloride ion. The cold storage material according to claim 1.
The halide ion further comprises at least one selected from the group consisting of fluoride ions and bromide ions.
Cold storage material. The cold storage material according to claim 1.
The cold storage material has a heat of fusion of 160 joules / gram or more in the range of 2 degrees Celsius or more and 8 degrees Celsius or less.
Cold storage material. The cold storage material according to claim 1.
The mole fraction of water is 0.7 or more and 0.99 or less.
Cold storage material. The cold storage material according to claim 1.
Table molar concentration of the halide ion, the chemical formula _{[(CH 3 CH 2 CH 2} CH 2) 4 N] by tetra -n- butyl ammonium ions and formula _NH ^{4 +} is represented by ⁺ containing the chloride ion Equal to the sum of the molar concentrations of ammonium ions
Cold storage material. It ’s a cooler box,
The cold storage material according to claim 1 is provided.
Cooler box. The cooler box according to claim 8.
Contains liquid medicines or foods,
Cooler box.

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