JPH0867869A - Heat storage material package and heat storage method - Google Patents

Abstract

(57) [Abstract] [Purpose] Excessive heat or cold generated when a compound exhibiting an exothermic or endothermic reaction is dissolved in water is stored quickly and without loss, and an appropriate temperature is maintained for a long time to an object. A heat storage material package to be obtained, and a method capable of immediately generating heat or cooling, which lasts for a long time are provided. [Structure] Basically, a heat storage material package containing a compound which dissolves in water and exhibits an exothermic or endothermic reaction, microcapsules containing a heat storage material, and water and which holds at least a non-contact state is used. When cold heat or warm heat is required, the non-contact state with and is released, and and are put into a mixed state. As the compound of, calcium chloride,
Urea, ammonium nitrate or the like is used. As the heat storage material in the microcapsules, n-paraffin, ester compounds, polyhydrates of various inorganic compounds, and the like are used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat storage material capable of keeping a human body, food, medicine, etc. for a long period of time or keeping it cold. More specifically, it is easy to carry and requires heat or cold. The present invention relates to a heat storage material package capable of being taken out immediately at any time and capable of maintaining appropriate warmth or coolness for a long time, and a heat storage method thereof.

[0002]

2. Description of the Related Art It is well known that a certain type of inorganic or organic compound is dissolved in water to cause an exothermic or endothermic reaction. Depending on the type of compound or the concentration of dissolved compound, heat or cold in various temperature ranges can be obtained. be able to. Utilizing this phenomenon, for example, it is known that calcium chloride powder is directly sprayed on the snow surface to perform snow melting, but an example that is directly used for keeping heat or cold for human bodies and foods is Few. The main reason is that the temperature range generated when a compound is dissolved in water is extremely high and vice versa, and the temperature of 0 to 60 ° C, which is generally suitable for the human body, is maintained for a long time. Is difficult. For example, under normal room temperature, 100g of calcium chloride powder
When added to 100 g of water at 20 ° C, the temperature of the water reaches about 90 ° C in a short time, but 10 minutes later, it drops to 30 ° C, which is not suitable for keeping the human body warm.

Although a method of adding an organic compound such as sugar together with a compound exhibiting a heat of dissolution has been proposed in an attempt to increase the retention time, the effect is not sufficient.
In addition, even if various inorganic salts and solubility control agents are used in combination, the duration is almost shortened, and effective means have not been found.

[0004]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is that the excessive temperature or cold generated when a compound exhibiting an exothermic or endothermic reaction is dissolved in water and the temperature is comfortable and suitable even when it is in contact with the human body. It is intended to provide a heat storage material package capable of immediately generating and storing heat, and maintaining the temperature for a long time, and a heat storage method thereof.

[0005]

The object of the present invention is to: 1. A compound which basically dissolves in water and exhibits an exothermic or endothermic reaction,
To obtain a heat storage material package containing microcapsules encapsulating the heat storage material and water, and holding at least and in a non-contact state, 2. Release the non-contact state with the heat storage material package. This is achieved by bringing and into a mixed state. That is, when the compositions of and in the heat storage material package are mixed, a rapid exothermic or endothermic reaction occurs by first dissolving the compound in water.
The excessively generated hot heat or cold heat is preferentially stored in the heat storage material in the microcapsule, so that the heat is prevented from being radiated to the outside and no remarkable overheating or overcooling immediately after melting occurs. After the dissolution of the further compound, the latent heat stored in the heat storage material in the microcapsules gradually begins to be released to the outside, and the effect of heat or cold continues for a long time.

Specific examples of the compound used in the present invention which exhibits an exothermic or endothermic reaction when dissolved in water include calcium chloride, magnesium chloride, sodium hydroxide, zinc sulfate, calcium sulfate, and the like.
Copper sulfate and the like, as a compound that exhibits an endothermic reaction,
Potassium chloride, potassium nitrate, barium nitrate, phosphoric acid,
Potassium iodide, sodium nitrate, ammonium nitrate,
Benzoic acid, succinic acid, salicylic acid, urea, citric acid and the like, but among them, as a compound exhibiting an exothermic reaction, calcium chloride, as a compound exhibiting an endothermic reaction,
Ammonium nitrate and urea are preferred. These may be used alone or in combination of two or more.

The microcapsules encapsulating the heat storage material in the present invention mean a solid or powder form, but in the actual manufacturing process, it is often obtained as an aqueous or oily dispersion liquid, and particularly in an aqueous dispersion system. It can be regarded as a mixture of microcapsules. The method for producing the microcapsules is not particularly limited as long as it is a method of coating the heat storage material with a water-insoluble film such as metal or synthetic resin, but as a method of physically or chemically forming a film, pressure-sensitive copying paper is used. Well-known methods for producing microcapsules for use are coacervation method using gelatin, in-situ polymerization method, interfacial polymerization method and the like as typical methods.

In addition to this, the encapsulation method by the composite emulsion method (JP-A-62-1452) and the method of spraying a thermoplastic resin on the surface of the heat storage material particles (JP-A-62-62).
No. 45680), a method of forming a thermoplastic resin in the liquid on the surface of the heat storage material particles (JP-A-62-149334), and a method of polymerizing and coating a monomer on the surface of the heat storage material particles (JP-A-62-149334). No. 62-225241), a method for obtaining a microcapsule of a water dispersion system described in a method for producing a polyamide-coated microcapsule by an interfacial polycondensation reaction (JP-A-2-258052), and the like.

As the encapsulating membrane material, in addition to metals such as aluminum and copper, polystyrene, polyacrylonitrile, polyamide, polyacrylamide, ethyl cellulose, polyurethane, aminoplast obtained by interfacial polymerization method, in situ method and the like can be used. Resins, and synthetic or natural resins utilizing the coacervation method of gelatin and carboxymethyl cellulose or gum arabic are used.

The heat storage material contained in the microcapsules obtained by the above means and membrane material is tridecane (C13),
N-paraffins such as tetradecane (C14), pentadecane (C15), hexadecane (C16), octadecane (C18), and
Inorganic eutectic and inorganic polyhydrate, fatty acids such as caprylic acid, lauric acid, stearic acid, higher alcohols having 12 or more carbon atoms, methyl myristate, methyl palmitate, methyl stearate and other ester compounds These heat storage materials may be used alone or in combination of two or more, which are appropriately selected depending on the kind of compound of the compound and the intended holding temperature range. If necessary, a supercooling preventing material, a specific gravity adjusting material, a deterioration preventing agent, a film reinforcing material and the like can be added together with the heat storage material in the microcapsule.

The particle size of the microcapsules is not particularly limited, but it is preferably as small as possible in order to quickly absorb the heat of dissolution, and particularly preferably 1 mm or less. Before the heat storage material package according to the present invention requires warm heat or cold heat, it must be kept in a state of being in non-contact with at least one of the constituent compositions. Specifically, the first packaging material or the like may be filled first, and the mixture of and may be collected and packed in the second packaging material. Further, for those obtained in an aqueous dispersion system as the production conditions of the microcapsules, since the dispersion medium existing around the microcapsules exerts the effect of water, one of the compound and the microcapsule aqueous dispersion liquid is used. The heat storage material package of the present invention can also be obtained by collectively filling the first packaging material with the second packaging material.

The heat storage material package of the present invention has an appropriate amount of heat or cold by applying an external impact when heat or cold is required to destroy the first package material and release the non-contact state of. A long-lasting effect can be obtained.

The microcapsules of the present invention are mixed in an amount of 150 parts by weight or less, preferably 5 to 100 parts by weight, per 100 parts by weight of the compound. Water is compound 10
It is usually added in the range of 10 to 150 parts with respect to 0 part, but the mixing ratio of these is the kind of compound, the solubility in water,
It is appropriately adjusted depending on the degree of heat generation or heat absorption (enthalpy of dissolution). If necessary, thickener, pH
It is also possible to add a regulator, a water-absorbent resin, a deterioration inhibitor and the like.

As the packaging material used in the heat storage material package of the present invention, a synthetic resin film of polyethylene, polypropylene, nylon or the like is used, but it is used as an aqueous dispersion of the first packaging material for isolation. Is weaker in strength than the outer packaging material, and a heat storage material package is obtained by filling the second high-strength packaging material.

[0015]

EXAMPLES Examples of the present invention will be described below. Example 1 Method for producing microcapsule 5 g of melamine powder was added to 37% aqueous formaldehyde solution 6.
After adjusting the pH to 8 by adding 5 g and 10 g of water, about 70
It heated up to (degreeC) and the melamine-formalin initial condensate aqueous solution was obtained. In 100 g of a 5% styrene-maleic anhydride copolymer sodium salt aqueous solution whose pH was adjusted to 4.5,
80 g of n-pentadecane having a melting point of 9 ° C. was added as a heat storage material with vigorous stirring, and emulsification was carried out until the particle size became about 50 μm. The whole amount of the above melamine-formaldehyde initial condensate aqueous solution was added to the above emulsion and stirred at 70 ° C. for 2 hours, then the pH was adjusted to 9 and the encapsulation was completed.

Method for producing heat storage material package This microcapsule dispersion liquid was diluted with water to adjust the solid content concentration to 40% (w / w), and 100 g of the dispersion liquid was added to 10 cm of 20 μm thickness.
It was filled in a bag made of polyethylene on all sides, and 100 g of ammonium nitrate was also filled together in the same polyethylene film having a thickness of 100 μm to obtain a heat storage material package. When a fist shock was applied to this heat storage material package, the bag of the microcapsule dispersion liquid in the package broke and cooling started immediately and a pleasant cold sensation lasted for a long time.

On the other hand, instead of this microcapsule dispersion liquid, 100 g of water was filled in a packaging material to prepare a heat storage material package in the same manner, and shock was similarly applied to cool it. As a result, the minimum cooling temperature was extremely low, but the cooling duration was about half or less that when using the microcapsule dispersion.

Example 2 In the same encapsulation method as in Example 1, paraffin wax having a melting point of 90 ° C. was microencapsulated as a heat storage material instead of n-pentadecane, and the solid content concentration was 40% (w / w). A microcapsule aqueous dispersion of was obtained. 100 g of this microcapsule aqueous dispersion was filled in a 10 cm square polyethylene bag with a thickness of 20 μm, and calcium chloride (anhydrous) 10
The same polyethylene film having a thickness of 100 μm was filled together with 0 g to obtain a heat storage material package. When a fist shock was applied to this heat storage material package, the bag of the microcapsule dispersion liquid in the package broke and heat immediately started, and a pleasant warm feeling lasted for a long time. On the other hand, the same amount of water was used instead of the microcapsule dispersion and mixed with 150 g of calcium chloride, but the package became extremely hot and could not even be touched for a while.

[0019]

As shown in the above examples, by obtaining the heat storage material package of the present invention, it is possible to take out hot heat or cold heat immediately when necessary, and further, excessively cold or overheated. It is possible to maintain a suitable temperature for a long time even when it comes into contact with a human body part, and to keep food and medicine warm and cool for a long time.

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Claims (2)

[Claims] 1. A heat storage material package, which basically comprises a compound which dissolves in water and exhibits an exothermic or endothermic reaction, microcapsules containing a heat storage material, and water, and which is held in a non-contact state with at least . 2. A heat storage method in which the non-contact state with the inside of the heat storage material package according to claim 1 is released and the heat storage material package is brought into a mixed state.