Cooling materials and cooler boxes

Abstract

A cold storage material of the present disclosure contains: tetrahydrofuran; water; and at least one silver compound selected from the group consisting of silver phosphate represented by the chemical formula Ag3PO4, silver carbonate represented by the chemical formula Ag2CO3; and silver oxide represented by the chemical formula AgO. This cold storage material has a melting point of 2-8 degrees Celsius, and a crystallization temperature of at least 0 degrees Celsius but less than the boiling point.

Description

[Technical Field]

[0001] The present disclosure relates to a cold storage material and a cooler box. [Background technology]

[0002] Patent Document 1 discloses a cold storage material that forms a clathrate hydrate upon cooling. The cold storage material of Sample C-6 disclosed in Patent Document 1 is composed of 0.05 mmol of AgI and a 19 wt % aqueous solution of tetrahydrofuran. The cold storage material of Sample C-6 has a melting point of 4.6 degrees Celsius and a crystallization temperature of minus 7 degrees Celsius. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-059676 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a cold storage material suitable for preserving and refrigerating medicines or food. [Means for solving the problem]

[0005] The cold storage material according to the present disclosure is tetrahydrofuran, water, and Contains at least one silver compound selected from the group consisting of silver phosphate represented by the chemical formula Ag3PO4, silver carbonate represented by the chemical formula Ag2CO3, and silver oxide represented by the chemical formula AgO, The regenerator material has a melting point of 2 degrees Celsius or more and 8 degrees Celsius or less, The regenerator material has a crystallization temperature of 0° C. or higher and lower than the melting point. [Effects of the Invention]

[0006] The present disclosure provides a cold storage material suitable for storing and refrigerating medicines or food. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a graph showing the characteristics of the cold storage material according to the first embodiment during cold storage. [Figure 2] FIG. 2 is a graph showing the characteristics of the cold storage material according to the first embodiment when it is allowed to cool. [Figure 3] FIG. 3 is a schematic diagram of a cooler box according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the following embodiments.

[0009] (First embodiment) 1 is a graph showing the characteristics of the regenerator material according to the first embodiment during cooling, in which the horizontal and vertical axes represent time t and temperature T, respectively.

[0010] The regenerator material according to the first embodiment is cooled. See section A in FIG. 1. Unlike a typical liquid, as is well known in the field of regenerator materials, even if the regenerator material is cooled to its melting point Tm, the regenerator material does not solidify but remains in a supercooled state. See section B in FIG. 1. In the supercooled state, the regenerator material is liquid.

[0011] Then, the regenerator material begins to spontaneously crystallize. As the regenerator material crystallizes, it releases heat of crystallization that is approximately equal to the latent heat. As a result, the temperature of the regenerator material begins to rise. See section C in FIG. 1. In this specification, the temperature at which the regenerator material spontaneously crystallizes is referred to as the "crystallization temperature Tc."

[0012] ΔT represents the difference between the melting point Tm and the crystallization temperature Tc of the regenerator material. ΔT is also called the "degree of supercooling." When the regenerator material crystallizes in a supercooled state, the regenerator material becomes, for example, a clathrate hydrate (see, for example, Patent Document 1). Here, clathrate hydrate refers to a crystal formed when water molecules form a cage-like crystal through hydrogen bonding, and substances other than water are enclosed within it. The concentration at which water molecules and guest molecules form a clathrate hydrate in just the right amount is called the congruent concentration. Generally, clathrate hydrates are often used near the congruent concentration.

[0013] After the crystallization is completed and the heat of crystallization of the regenerator material is released, the temperature of the regenerator material gradually decreases to be equal to the ambient temperature. See section D in FIG. 1. In FIG. 1, the regenerator material is cooled to a temperature lower than the crystallization temperature Tc. However, the temperature of the regenerator material may be maintained in a temperature range between the melting point Tm and the crystallization temperature Tc.

[0014] The crystallization temperature Tc of the regenerator material is lower than the melting point Tm of the regenerator material. The melting point of the regenerator material can be measured using a differential scanning calorimeter, also known as "DSC," as is well known in the regenerator material art.

[0015] FIG. 2 is a graph showing the characteristics of the cold storage material in the first embodiment during heating. In FIG. 2, the horizontal and vertical axes represent time t and temperature T, respectively. During section E, the temperature of the cold storage material is maintained at or below the melting point Tm of the cold storage material. For example, while the lid of the cooler box is closed, the temperature inside the cooler box is set to or below the melting point Tm of the cold storage material so that the temperature of the cold storage material placed in the cooler box is maintained at or below the melting point Tm of the cold storage material. During section E, the temperature of the cold storage material may be maintained at or below the crystallization temperature Tc.

[0016] Next, the ice pack is gradually heated. See section F in Figure 2. For example, at the end of section E, i.e., the beginning of section F, if the lid of the cooler box is opened or the lid is opened and food is placed inside, the temperature inside the cooler box will gradually increase.

[0017] When the temperature of the cold storage material reaches its melting point Tm, the temperature of the cold storage material is maintained near the melting point Tm. See section G in Figure 2. If there is no cold storage material, the temperature inside the cooler box will continuously rise as shown in section Z in Figure 2. On the other hand, if there is a cold storage material, the temperature inside the cooler box will be maintained near the melting point of the cold storage material for a certain period of time in section G. In this way, the cold stored in the cold storage material keeps the coolant cool. At the end of section G, the crystals in the cold storage material melt and disappear. As a result, the cold storage material liquefies.

[0018] The temperature of the liquefied regenerator material then rises to equalize with the ambient temperature (see section H in Figure 2).

[0019] The regenerator material can be cooled and reused.

[0020] It is important that a cold storage material suitable for use in a cooler box capable of storing medicines or foodstuffs satisfies the following conditions (I) and (II). Condition (I) The regenerator material has a melting point of 2 degrees Celsius or more and 8 degrees Celsius or less. As an example, the regenerator material has a melting point of 3.0 degrees Celsius or more and 7 degrees Celsius or less. Condition (II): The regenerator material has a crystallization temperature Tc of 0° C. or higher and lower than the melting point Tm. For example, the regenerator material has a crystallization temperature Tc of 0° C. or higher and lower than 3.0° C. (for example, 2.5° C. or lower).

[0021] To preserve medicines and food, the inside of the cooler box must be maintained at a temperature of approximately 2°C or higher and 8°C or lower, so condition (I) must be met. If the temperature inside the cooler box is maintained below 0°C, the water contained inside the medicines and food will turn to ice, which may cause the medicines and food to deteriorate. On the other hand, if the temperature inside the cooler box is maintained at a temperature above 8°C, the cooler box will not function effectively.

[0022] By satisfying condition (II), the efficiency of the section in which the regenerator material is cooled to achieve its function, i.e., section B shown in Figure 1, can be increased. Hereinafter, this efficiency will be referred to as "crystallization efficiency." The crystallization efficiency decreases as the crystallization temperature Tc decreases. As is clear from Figure 1, particularly section B in Figure 1, for example, to cool a regenerator material having a crystallization temperature of -18 degrees Celsius to achieve its function, the regenerator material must be cooled in a freezer maintained at a temperature lower than -18 degrees Celsius, e.g., -20 degrees Celsius. Hereinafter, a regenerator material having a crystallization temperature Tc of -18 degrees Celsius will be referred to as a "minus-18 regenerator material." On the other hand, to cool a regenerator material having a crystallization temperature Tc of -1 degrees Celsius to achieve its function, the regenerator material must be cooled in a freezer maintained at a temperature lower than -1 degree Celsius. Hereinafter, a regenerator material having a crystallization temperature Tc of -1 degree Celsius will be referred to as a "minus-1 regenerator material." The energy required to cool a minus 1 regenerator is less than the energy required to cool a minus 18 regenerator. Therefore, the higher the crystallization temperature Tc, the better the crystallization efficiency.

[0023] In the art, the heat of fusion is also called the latent heat.

[0024] To avoid confusion, the present specification uses "Kelvin" for the degree of supercooling ΔT. For example, the present inventors will write "the degree of supercooling ΔT is n Kelvin or less." Needless to say, n is a real number. The description "degree of supercooling ΔT≦5 Kelvin" means that the difference between the melting point Tm and the crystallization temperature Tc of the regenerator material is 5 Kelvin or less. On the other hand, the present specification uses "Celsius" to describe temperature. For example, the present inventors will write "the crystallization temperature Tc is 5 degrees Celsius." 5 degrees Celsius can also be expressed as 5°C.

[0025] The cold storage material according to the first embodiment is tetrahydrofuran, water, and At least one silver compound selected from the group consisting of silver phosphate represented by the chemical formula Ag3PO4, silver carbonate represented by the chemical formula Ag2CO3, and silver oxide represented by the chemical formula AgO. Contains:

[0026] As will be demonstrated in the examples described later, the cold storage material according to the first embodiment has a melting point Tm of 2° C. or more and 8° C. or less. Therefore, the cold storage material according to the first embodiment is suitable for use in preserving medicines and foods.

[0027] As demonstrated in the examples described later, the cold storage material according to the first embodiment has a crystallization temperature Tc of 0 degrees Celsius or higher. On the other hand, as explained in the section on prior art, the cold storage material according to sample C-6 of Patent Document 1 has a crystallization temperature Tc of minus 7 degrees Celsius. Therefore, the cold storage material according to the first embodiment has a higher crystallization efficiency than the cold storage material described in Patent Document 1. In other words, the energy required in section B where the cold storage material according to the first embodiment is cooled is smaller than that of the cold storage material according to sample C-6 of Patent Document 1.

[0028] 1, the crystallization temperature Tc of the regenerator material is lower than the melting point Tm of the regenerator material. The degree of supercooling ΔT of the regenerator material may be, for example, greater than zero and equal to or less than 8 Kelvin, or may be equal to or greater than 1 Kelvin and equal to or less than 5 Kelvin.

[0029] The cold storage material according to the first embodiment contains at least one silver compound selected from the group consisting of silver phosphate represented by the chemical formula AgPO, silver carbonate represented by the chemical formula AgCO, and silver oxide represented by the chemical formula AgO. As demonstrated in the comparative examples described below, when other silver compounds, such as silver iodide, silver bromide, or silver chloride, are used instead of these three silver compounds, the crystallization temperature Tc is lowered. Similarly, as demonstrated in the comparative examples described below, when other metal salts, such as titanium oxide, vanadium oxide, iron oxide, nickel oxide, manganese oxide, or zinc oxide, are used instead of these three silver compounds, the crystallization temperature Tc is also lowered.

[0030] The molar ratio of tetrahydrofuran to water in the cold storage material according to the first embodiment is not limited to a specific value, as long as the cold storage material according to the first embodiment has a melting point Tm of 2°C or more and 8°C or less, and a crystallization temperature Tc of 0°C or more and less than the melting point Tm. As an example, the molar ratio is 0.05 or more and 0.07 or less. It is known that when a cold storage material having a molar ratio of tetrahydrofuran to water of 1 / 17 is cooled, clathrate hydrate crystals are formed with just the right amount of water or tetrahydrofuran. When the molar ratio of tetrahydrofuran to water is 0.05 or more and 0.07 or less, the molar ratio is close to 1 / 17, and the cold storage material is likely to have a large latent heat.

[0031] As demonstrated by Examples 1A to 3D, in the regenerator material of the first embodiment, the molar ratio of the silver compound to water is not limited to a specific value. As an example, the molar ratio is 2.64 × 10 -8 Over 3.70 x 10 -4 The following is the result.

[0032] The cold storage material according to the first embodiment may contain additives other than tetrahydrofuran, water, and the silver compound, as long as it has a melting point Tm of 2 degrees Celsius or more and 8 degrees Celsius or less, and a crystallization temperature Tc of 0 degrees Celsius or more and less than the melting point Tm.

[0033] The content of the additive is not limited to a specific value. The ratio of the content of the additive to the total amount of tetrahydrofuran, water, and the above silver compound is, for example, 0.1 or less, or may be 0.05 or less, or may be 0.01 or less, by mass. Examples of the additive include a supercooling inhibitor, a thickener, and a preservative.

[0034] The cold accumulating material according to the first embodiment may not contain any additives, in other words, the cold accumulating material according to the first embodiment may be composed only of tetrahydrofuran, water, and the silver compound, excluding impurities that may be inevitably mixed in.

[0035] The cold storage material according to the first embodiment can be produced by mixing, for example, tetrahydrofuran, water, and the silver compound.

[0036] (Second embodiment) A cooler box according to the second embodiment will be described below.

[0037] FIG. 3 shows a schematic diagram of a cooler box 100 according to the second embodiment.

[0038] The cooler box 100 comprises an insulated box 101 consisting of a bottom (not shown) and sides, and an insulated lid 102 .

[0039] The cold storage material according to the first embodiment is provided along at least one selected from the group consisting of the inside bottom surface of the insulating box 101, the inside side surface of the insulating box 101, and the inside surface of the insulating lid 102, i.e., the lower surface of the insulating lid 102. In Fig. 3, cold storage material packs 110 containing the cold storage material according to the first embodiment are provided so as to contact each of the four inside side surfaces of the insulating box 101 having a rectangular parallelepiped shape.

[0040] 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 insulated box 101, the inside of the side of the insulated box 101, and the inside of the insulated lid 102. The cold storage material according to the first embodiment may be contained in a cold storage material pack 110 and placed in the internal space of the cooler box 100. The internal space of the cooler box 100 is a space formed by the inside bottom surface of the insulated box 101, the inside side surface of the insulated box 101, and the inside surface of the insulated lid 102.

[0041] The cold storage material according to the first embodiment may be provided inside at least one selected from the group consisting of the side of the insulating box 101, the insulating lid 102 of the insulating box 101, and the insulating box 101 itself. In this case, the cold storage material according to the first embodiment may also be provided in a state where it is contained in the cold storage material pack 110.

[0042] It is desirable that at least one selected from the group consisting of medicines and food products be placed inside the insulated box 101. In FIG. 3, medicine 120 is placed inside the insulated box 101. An example of the medicine is a liquid medicine. An example of a liquid medicine is a vaccine. When a vaccine is transported, it is required to be stored at a temperature of, for example, 2 degrees Celsius or higher and 8 degrees Celsius or lower to maintain its quality. The medicine may be a solid medicine or a gel medicine. The cooler box according to the second embodiment is suitable for transporting vaccines because the ice storage material according to the first embodiment has a melting point of 2 degrees Celsius or higher and 8 degrees Celsius or lower. [Example]

[0043] The present disclosure will now be described in more detail with reference to the following examples.

[0044] In this example, silver phosphate is represented by the chemical formula Ag3PO4. Silver phosphate was purchased from Mitsuwa Chemical Co., Ltd. In this example, silver carbonate is represented by the chemical formula Ag2CO3. Silver carbonate was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. In this example, silver oxide is represented by the chemical formula AgO. In other words, in this specification, silver oxide is silver(II) oxide, not silver(I) oxide, which is represented by the chemical formula Ag2O. Silver oxide was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. In this example, tetrahydrofuran is abbreviated as "THF." THF was purchased from Tokyo Chemical Industry Co., Ltd.

[0045] Example 1A (Method of manufacturing the cold storage material) First, the reagents shown in Table 1 below were added to a screw tube having a capacity of 60 milliliters to obtain a mixture. The mixture was thoroughly stirred in the screw tube to obtain the cold storage material of Example 1A. The screw tube was a glass tube to which a screw-equipped lid could be attached.

[0046] [Table 1]

[0047] (Melt point and crystallization temperature measurements) A screw tube containing approximately 6 grams of the heat accumulator material according to Example 1A was placed inside an Espec Corporation SU-241 thermostatic chamber. A thermocouple was attached to the screw tube to measure the temperature inside the screw tube. The temperature of the thermostatic chamber was maintained at 20°C for 2 hours. The temperature of the thermostatic chamber was then decreased at a rate of 1°C per minute. After the temperature of the thermostatic chamber reached 4°C, the temperature of the thermostatic chamber was maintained at 4°C for 30 minutes.

[0048] The temperature of the thermostatic chamber was then decreased from 4°C to minus 20°C at a rate of 1°C per 24 hours. The temperature of the regenerator material according to Example 1A placed in the thermostatic chamber was recorded using a thermocouple and a Keyence NR-600 data logger. The crystallization temperature of the regenerator material according to Example 1A was calculated from the temperature of the regenerator material at the start of the rapid increase in temperature (see section C in Figure 1) and the melting point (described in the next paragraph).

[0049] The cold storage material according to Example 1A was placed in a thermostatic chamber and maintained at minus 20 degrees Celsius for three hours. The temperature of the thermostatic chamber was then increased at a rate of 1 degree Celsius per minute. The melting point of the cold storage material according to Example 1A was measured using a differential scanning calorimeter (DSC). As a result, the melting point of the cold storage material according to Example 1A was 4.5 degrees Celsius.

[0050] Example 1B In Example 1B, an experiment similar to that of Example 1A was conducted, except for the following: the reagents shown in Table 2 were used instead of the reagents shown in Table 1. In addition, a screw cap tube having a capacity of 110 milliliters was used instead of a screw cap tube having a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0051] [Table 2]

[0052] Example 1C In Example 1C, an experiment similar to that of Example 1A was conducted, with the following exceptions: the reagents shown in Table 3 were used instead of the reagents shown in Table 1; and a screw cap tube with a capacity of 110 milliliters was used instead of a screw cap tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0053] [Table 3]

[0054] Example 1D In Example 1D, an experiment similar to Example 1A was conducted, except for the following: the cold storage material and reagents shown in Table 4 below were mixed instead of the reagents shown in Table 1. In addition, a screw tube with a capacity of 110 milliliters was used instead of the screw tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0055] [Table 4]

[0056] Example 2A In Example 2A, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 5 below were used instead of the reagents shown in Table 1. The results of the experiment are shown in Table 27.

[0057] [Table 5]

[0058] Example 2B In Example 2B, an experiment similar to that of Example 1A was conducted, with the following exceptions: the reagents shown in Table 6 were used instead of the reagents shown in Table 1; and a screw cap tube with a capacity of 110 milliliters was used instead of a screw cap tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0059] [Table 6]

[0060] Example 2C In Example 2C, an experiment similar to that of Example 1A was conducted, with the following exceptions: the reagents shown in Table 7 were used instead of the reagents shown in Table 1; and a screw cap tube with a capacity of 110 milliliters was used instead of a screw cap tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0061] [Table 7]

[0062] Example 2D In Example 2D, an experiment similar to that of Example 1A was conducted, except for the following: Instead of the reagents shown in Table 1, the cold storage material and reagents shown in Table 8 below were mixed. In addition, a screw tube with a capacity of 110 milliliters was used instead of the screw tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0063] [Table 8]

[0064] Example 3A In Example 3A, an experiment similar to Example 1A was carried out, except that the reagents shown in Table 9 below were used instead of the reagents shown in Table 1. The results of the experiment are shown in Table 27.

[0065] [Table 9]

[0066] Example 3B In Example 3B, an experiment similar to that of Example 1A was conducted, with the following exceptions: the reagents shown in Table 10 were used instead of the reagents shown in Table 1; and a screw cap tube with a capacity of 110 milliliters was used instead of a screw cap tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0067] [Table 10]

[0068] Example 3C In Example 3C, an experiment similar to that of Example 1A was conducted, with the following exceptions: the reagents shown in Table 11 were used instead of the reagents shown in Table 1; and a screw cap tube having a capacity of 110 milliliters was used instead of a screw cap tube having a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0069] [Table 11]

[0070] Example 3D In Example 3D, an experiment similar to that of Example 1A was conducted, except for the following: Instead of the reagents shown in Table 1, the reagents and ice packs shown in Table 12 below were mixed. In addition, a screw tube with a capacity of 110 milliliters was used instead of a screw tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0071] [Table 12]

[0072] (Reference Example 1A) In Reference Example 1A, an experiment similar to Example 1A was carried out, except that the reagents shown in Table 13 below were mixed instead of the reagents shown in Table 1. The results of the experiment are shown in Table 27.

[0073] [Table 13]

[0074] (Reference example 1B) In Reference Example 1B, an experiment similar to that of Example 1A was conducted, except for the following points: the reagents shown in Table 14 were used instead of the reagents shown in Table 1; and a screw cap tube with a capacity of 110 milliliters was used instead of a screw cap tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0075] [Table 14]

[0076] (Reference example 1C) In Reference Example 1C, an experiment similar to that of Example 1A was conducted, except for the following points: the reagents shown in Table 15 were used instead of the reagents shown in Table 1; and a screw cap tube with a capacity of 110 milliliters was used instead of a screw cap tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0077] [Table 15]

[0078] (Reference Example 1D) In Reference Example 1D, an experiment similar to that of Example 1A was conducted, except for the following points: Instead of the reagents shown in Table 1, the reagents and cold storage material shown in Table 16 below were mixed. In addition, a screw tube with a capacity of 110 milliliters was used instead of the screw tube with a capacity of 60 milliliters. The results of the experiment are shown in Table 27.

[0079] [Table 16]

[0080] (Reference example 2) In Reference Example 2, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 17 below were mixed instead of the reagents shown in Table 1. The results of the experiment are shown in Table 27. Note that heavy water was used in Reference Example 2.

[0081] [Table 17]

[0082] (Comparative Example 1) In Comparative Example 1, an experiment similar to Example 1A was carried out, except that the reagents shown in Table 18 below were mixed instead of the reagents shown in Table 1. Silver iodide was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. The results of the experiment are shown in Table 27.

[0083] [Table 18]

[0084] (Comparative Example 2) In Comparative Example 2, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 19 below were mixed instead of the reagents shown in Table 1. Silver bromide was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. The results of the experiment are shown in Table 27.

[0085] [Table 19]

[0086] (Comparative Example 3) In Comparative Example 3, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 20 below were mixed instead of the reagents shown in Table 1. Silver chloride was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. The results of the experiment are shown in Table 27.

[0087] [Table 20]

[0088] Comparative Example 4 In Comparative Example 4, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 21 below were mixed instead of the reagents shown in Table 1. Titanium oxide was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. The results of the experiment are shown in Table 27.

[0089] [Table 21]

[0090] (Comparative Example 5) In Comparative Example 5, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 22 below were mixed instead of the reagents shown in Table 1. Vanadium oxide was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. The results of the experiment are shown in Table 27.

[0091] [Table 22]

[0092] (Comparative Example 6) In Comparative Example 6, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 23 below were mixed instead of the reagents shown in Table 1. Iron oxide was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. The results of the experiment are shown in Table 27.

[0093] [Table 23]

[0094] (Comparative Example 7) In Comparative Example 7, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 24 below were mixed instead of the reagents shown in Table 1. Nickel oxide was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. The results of the experiment are shown in Table 27.

[0095] [Table 24]

[0096] (Comparative Example 8) In Comparative Example 8, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 25 below were mixed instead of the reagents shown in Table 1. Manganese oxide was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. The results of the experiment are shown in Table 27.

[0097] [Table 25]

[0098] (Comparative Example 9) In Comparative Example 9, an experiment similar to that of Example 1A was carried out, except that the reagents shown in Table 26 below were mixed instead of the reagents shown in Table 1. Zinc oxide was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. The results of the experiment are shown in Table 27.

[0099] [Table 26]

[0100] The heat accumulating materials according to Examples 1A, 2A, and 3A, Reference Example 1A, Reference Example 2, and Comparative Examples 1 to 9 had a volume of approximately 6 milliliters. The heat accumulating materials according to Examples 1B to 1D, Examples 2B to 2D, Examples 3B to 3D, and Reference Examples 1B to 1D had a volume of approximately 100 milliliters.

[0101] [Table 27]

[0102] As is clear from Examples 1A to 3D, the regenerator material containing THF, water, and at least one silver compound selected from the group consisting of silver phosphate, silver carbonate, and silver oxide has a melting point of 4.5 degrees Celsius and a crystallization temperature of 1 degree Celsius or more and 2 degrees Celsius or less.

[0103] On the other hand, as is clear from Comparative Examples 1 to 3, the ice accumulator containing THF, water, and silver halide other than silver fluoride has a melting point of 4.5 degrees Celsius, but a crystallization temperature of minus 7 degrees Celsius or lower.

[0104] As is clear from Comparative Examples 4 to 9, the regenerator material containing THF, water, and metal oxides other than silver oxide has a melting point of 4.5 degrees Celsius, but a crystallization temperature of minus 8 degrees Celsius or lower.

[0105] As described above, the heat exchanger materials according to Examples 1A to 3D have higher crystallization temperatures than the heat exchanger materials according to Comparative Examples 1 to 9, and therefore the heat exchanger materials according to Examples 1A to 3D have higher crystallization efficiencies than the heat exchanger materials according to Comparative Examples 1 to 9.

[0106] As is clear from a comparison of Examples 1A to 3D, it is understood that the content of the silver compound in the regenerator material does not affect the crystallization temperature. [Industrial Applicability]

[0107] The cold storage material according to the present disclosure can be used for a cooler box suitable for storing and refrigerating liquid medicines or food.

Claims

1. A cold storage material, tetrahydrofuran, water, and Chemical formula Ag 3 P.O. 4 Silver phosphate, represented by the chemical formula Ag 2 CO 3 and silver oxide represented by the chemical formula AgO, The regenerator material has a melting point of 2 degrees Celsius or more and 8 degrees Celsius or less, The regenerator material has a crystallization temperature of 0 degrees Celsius or higher and lower than the melting point. Cold storage material.

2. The cold storage material according to claim 1, The silver compound is silver phosphate. Cold storage material.

3. The cold storage material according to claim 1, The silver compound is silver carbonate. Cold storage material.

4. The cold storage material according to claim 1, The silver compound is silver oxide. Cold storage material.

5. The cold storage material according to any one of claims 1 to 4, a molar ratio of the tetrahydrofuran to the water is 0.05 or more and 0.07 or less; Cold storage material.

6. A cooler box, The cooling storage material according to any one of claims 1 to 5 is included. Cooler box.

7. The cooler box according to claim 6, Liquid medicine or food contained Cooler box.

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