JPH04252288A - Product with heat accumulating function - Google Patents

Abstract

PURPOSE:To prevent occurrence of broken pieces and cracks in a product with heat accumulating function comprising a heat accumulating material containing a latent heat accumulating material. CONSTITUTION:A heat accumulating material obtained by blending an ethylene-alpha-olefin copolymer having <=0.925g/cm<3> density is blended in a molten state with a crystalline organic compound to give a heat accumulating material.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a product with a heat storage function using a latent heat storage material that generates latent heat upon phase change.

0002

2. Description of the Related Art Latent heat storage materials that can store a large amount of heat at a constant temperature are beginning to be used for efficient energy use in houses and the like. For example, a product with a heat storage function has been proposed in which a heat storage body made of polyethylene and paraffin, which is a latent heat storage material, is formed into particles and dispersed in a base material such as cement.

The most popular latent heat storage material is a latent heat storage material that utilizes the latent heat required for phase transition between solid and liquid phases. In such a latent heat storage material that utilizes a phase transition between a solid phase and a liquid phase, its handling becomes a problem. In other words, consideration must be given to preventing the liquid from flowing out when it becomes liquid due to phase transition. Conventionally proposed heat storage bodies, for example, are made by melt-mixing polyethylene and paraffin, which is a latent heat storage material, so that the paraffin is dispersed in the polyethylene, so that it does not become liquid even when the paraffin is melted (Japanese Patent Application Laid-Open No. 59-1999) -170180, JP-A-61-279523). Japanese Patent Application Publication No. 5
In JP 9-170180, ultra-high molecular weight polyethylene is used as polyethylene in order to obtain a heat storage body with excellent shape stability when melting paraffin. Also, JP-A-6
No. 1-279523 uses crosslinked high density polyethylene.

0004

[Problems to be Solved by the Invention] However, conventional products with a heat storage function in which a granular heat storage material in which paraffin is dispersed in polyethylene are dispersed in a base material have a problem that the volumetric expansion of the granular heat storage material itself is large; Since a lot of paraffin oozes out from the granular heat storage material, the paraffin gets into the gaps in the base material, and its volumetric expansion and contraction tends to cause cracks in the base material part.

[0005] Accordingly, an object of the present invention is to provide a product with a heat storage function that can prevent cracks and cracks in the base material portion.

[0006]

[Means for Solving the Problems] In order to solve the above problems, it is necessary to (1) minimize the exudation of crystalline organic compounds from the heat storage body, and (2) reduce the volumetric expansion coefficient of the heat storage body (in particular, to It is necessary to make the volumetric expansion coefficient of the organic compound above and below the melting point as close as possible to that of the base material. Furthermore, when dispersing heat storage bodies in the form of particles or fibers into a base material, it may be difficult to disperse them because the base material and the granular heat storage bodies have different specific gravities. In order to improve the dispersibility into the base material, in addition to the above (1) and (2), it is effective to (2) make the specific gravity of the heat storage body approximately the same as that of the base material.

[0007] Therefore, the present invention provides a product with a heat storage function containing a heat storage body formed by melt-mixing a resin and a crystalline organic compound in a base material, in which the resin has a temperature of 0.92
Provided is a product with a heat storage function characterized by being an ethylene-α olefin copolymer A (hereinafter referred to as "copolymer A") having a density of 5 g/cm3 or less. In this invention, copolymer A, a crystalline organic compound,
Alternatively, at least one of an ethylene-α olefin copolymer having a higher density than copolymer A (hereinafter referred to as "copolymer B") and high-density polyethylene may be melt-mixed.

[0008] In the heat storage body of the present invention, an inorganic filler may be dispersed in the above two types of molten mixture. If the density of the copolymer A used in this invention is greater than 0.925 g/cm3, it is difficult to reduce seepage of the heat storage material even if it is an ethylene-α olefin copolymer. Even if the density is 0.925 g/cm3 or less, it is difficult to reduce seepage of the heat storage material unless it is an ethylene-α olefin copolymer. The density of copolymer A is 0.88 g/cm3
If it is smaller, it is possible for the heat storage body to have transparency when the crystalline organic compound melts.

Copolymer B used in this invention has a higher density than Copolymer A, and is compliant with JIS-K6.
760, including medium density polyethylene. If the density is lower than the density of copolymer A, the effect of maintaining the shape may not be high. The density of copolymer A is 0.89 g/
When the size is smaller than cm3, the crystallinity decreases, so addition of copolymer B is particularly effective for strength and shape retention. The density of copolymer B is preferably 0.910 g/
cm3 or more.

[0010] The ethylene-α olefin copolymer includes, for example, ethylene, propylene, butene-1
, pentane, hexene-1, 4-methylpentene-1,
Examples include copolymerization of α-olefin such as octene-1 at a ratio of several mol%.
It is not limited to this. Examples of the high-density polyethylene used in this invention include those specified by JIS-K6760. If high-pressure low-density polyethylene is used instead of high-density polyethylene, the shape of the heat storage body cannot be maintained.

The latent heat storage material used in this invention is a crystalline organic compound. Examples of crystalline organic compounds include organic compounds having a melting point of 90° C. or lower and a latent heat of 20 kcal/kg or higher, and ethylene-α olefin copolymer or high-density polyethylene copolymer or high-density polyethylene. Copolymers and those that are compatible with high-density polyethylene are desirable, and specific examples thereof include crystalline alkyl hydrocarbons (paraffin,
paraffin wax), crystalline fatty acids, and crystalline fatty acid esters (hereinafter, these two may be referred to as "crystalline fatty acids"). The crystalline organic compound has an appropriate melting point (
or freezing point) are selected and used. Preferably, the melting point of the crystalline organic compound is lower than the melting point of the ethylene-α olefin copolymer or high-density polyethylene to be blended.

When the melting temperature of the ethylene-α olefin copolymer blended is, for example, 110 to 120°C, the temperature at which heat is stored in the heat storage body according to the present invention is 110°C to 120°C.
It is necessary that the temperature is below 0°C. In order to efficiently store heat at this heat storage temperature, the melting point of the crystalline organic compound to be blended is 9
It is desirable that the temperature is 0°C or lower. In this invention, the mixing ratio of the resin (copolymer A; or copolymers A, B and high-density polyethylene) and the crystalline organic compound is appropriately set depending on the use of the heat storage body, and there are no particular limitations. However, for example, from the viewpoint of securing heat storage amount and heat storage material supporting ability, resin: 10 to 70 parts by weight, crystalline organic compound: 30 to 90 parts by weight. However, the total amount of the resin and the crystalline organic compound is 100 parts by weight. If the resin ratio is below the above range, the amount of seepage may increase. If the ratio of the resin exceeds the above range, the amount of heat storage may be too low. As a resin, copolymer A
, B and high-density polyethylene, for example, Copolymer A: 5 to 65 parts by weight, Total of copolymer B and high-density polyethylene: 5 to 65 parts by weight. However, the total amount of copolymer A, copolymer B, and high-density polyethylene is 10 to 70 parts by weight. If the ratio of copolymer A is below this range, there is a risk of increased bleeding. If the ratio of copolymer A exceeds this range, the amount of heat storage may be too low. If the total amount of copolymer B and high-density polyethylene is less than this range, the shape may not be maintained, and if it exceeds this range, the amount of heat storage may decrease.

[0013] In this invention, in order to appropriately adjust the density (or specific gravity) of the entire heat storage body, lower the seepage rate from the heat storage body, and increase the thermal conductivity of the heat storage body, the resin is used. Preferably, the inorganic filler is dispersed in the molten mixture of the crystalline organic compound and the crystalline organic compound. As the inorganic filler, for example, at least one selected from metals, metal salts, and carbon black can be used. These have a thermal conductivity much higher than that of resins such as crystalline organic compounds and ethylene-α-olefin copolymers.

The shape of the inorganic filler can be selected from various shapes such as granular (powder), fibrous, flake, and honeycomb shapes, and is not limited to any particular shape. There is no particular limit to the size. Examples of the metal include aluminum, copper, and stainless steel. Examples of metal salts include metal hydroxides, alumina, silica, talc, clay, and bentonite.

[0015] When metal is used as an inorganic filler, compared to other fillers, the rate of seepage can be reduced by adding a small amount,
It is possible to increase thermal conductivity. When a metal hydroxide is used as an inorganic filler, the combustibility of the heat storage body can be lowered, that is, it can be made difficult to burn. The metal hydroxide must be stable at the melting point of the ethylene-α-olefin copolymer and generate water when heated to a higher temperature. For example, aluminum hydroxide, magnesium hydroxide, etc. used. When the inorganic filler is a metal hydroxide, the hydroxyl group decomposes due to heat and a reaction occurs that releases water (for example, a reaction in which a metal hydroxide generates a metal oxide and water), which reduces the combustibility of the heat storage body. It gets lower.

[0016] In the present invention, the mixing ratio of the inorganic filler contained in the molten mixture is appropriately set depending on the degree of increase in the density of the heat storage body, the degree of increase in thermal conductivity, etc., and is not particularly limited. For example, the amount is 5 to 200 parts by weight based on the total of 100 parts by weight of the resin (copolymer A; or copolymers A, B and high-density polyethylene) and the crystalline organic compound. If the mixing ratio of the inorganic filler is below this range, there is a risk that the effects of bringing the density closer to that of the base material, reducing seepage, and increasing thermal conductivity may be less effective. If the mixing ratio of the inorganic filler exceeds this range, the amount of heat storage may be too low.

[0017] There are no particular limitations on the method of melt-mixing the resin and the crystalline organic compound, but for example, it is carried out by kneading with a kneader or the like at a temperature above the melting point of the resin such as a copolymer and below the thermal decomposition temperature. . When dispersing an inorganic filler, the inorganic filler is also added during kneading. By doing so, a uniform molten mixture can be obtained. The obtained molten mixture is molded into a desired shape, such as granules, fibers, or sheets, as necessary. The size (including thickness and length) of the heat storage body may be appropriately set depending on workability (or ease of handling), ease of manufacturing, and the like.

A product with a heat storage function is obtained by incorporating the heat storage body thus obtained into a base material. The heat storage material can be incorporated into the base material, for example, by dispersing granular or fibrous heat storage materials in the base material before solidifying (including curing) the base material, or by dispersing the heat storage material in the form of a sheet. This is done by overlapping the body and a plate-shaped base material and then solidifying them.

The base material is, for example, an inorganic binder or a mixture of an inorganic binder and aggregate. Examples of the inorganic binder and aggregate include those commonly used as building materials. Specific examples include, but are not limited to, cement, mortar, plaster, concrete, etc. The ratio between the base material and the heat storage body is
There is no particular limit, but it may be set as appropriate depending on the balance between the overall strength and heat storage performance of the product with a heat storage function. For example, the volume ratio of the heat storage body is 10 to 1
It is said to be 20 copies. If the ratio of the heat storage body is below this range, there is a risk that the heat storage performance will not be exhibited, and if it exceeds this range, the performance of the base material may not be maintained and it may easily collapse.

[0020] When the product with heat storage function of this invention is used in the construction of a house or the like, it is possible to construct the product made in advance in a factory, but it is also possible to manufacture and install the product with heat storage function at the construction site at the same time. It is also possible to do so, and the construction method is not particularly limited. For example, by thoroughly mixing the heat storage body and the raw material for the base material, and then applying or pouring it onto a desired area and solidifying it,
A product with a heat storage function is formed in which a heat storage body is dispersed in a base material.

[0021]

[Action] Because the ethylene-α-olefin copolymer A with a density of 0.925 g/cm3 or less and the crystalline organic compound are melt-mixed, the coefficient of volumetric expansion is small, and the amount of heat storage material seeps out from the heat storage body. decreases significantly. Density is 0
．． When using ethylene-α-olefin copolymer A smaller than 88 g/cm3, at least one of ethylene-α-olefin copolymer B and high-density polyethylene having a density higher than that of copolymer A should be added. Accordingly, the strength and shape stability of the heat storage body can be increased when the heat storage material is melted.

[0022] Inorganic fillers have a higher density than crystalline organic compounds and resins such as ethylene-α-olefin copolymers. Therefore, by adding an inorganic filler, the density of the entire heat storage body can be brought close to that of the base material (for example,
(to the same extent). In a product with a heat storage function using such a heat storage body, the heat storage body is well dispersed in the base material, and cracks and the like are less likely to occur.

[0023]

[Examples] Specific examples and comparative examples of the present invention are shown below, but the present invention is not limited to the following examples. In the following, "parts" represent "parts by weight." The ethylene-α olefin copolymer used in the following examples was “Nipolon-L F-15” manufactured by Toyo Soda Kogyo Co., Ltd.
” (density 0.925 g/cm3), “Excelen VL100” manufactured by Sumitomo Chemical Co., Ltd.
(density 0.900 g/cm3), "EUL130" manufactured by Sumitomo Chemical Co., Ltd. (density 0.900 g/cm3),
890 g/cm3), "Tafmar P0680" manufactured by Mitsui Petrochemical Co., Ltd.
Density 0.870 g/cm3). In all of these copolymers, the alpha olefin is butene-1 (in Tafmer P0680, the alpha olefin is propylene).

[0024] The polyethylenes used in the following comparative examples were high-density polyethylene "Shorex F6200V" manufactured by Showa Denko K.K. (density 0.955 g/cm3),
High-density polyethylene “Shorex S6006M” manufactured by Showa Denko K.K. (density 0.957 g/cm3)
), is.

The crystalline organic compounds used in the following Examples and Comparative Examples were crystalline alkyl hydrocarbon "Paraffin 125" manufactured by Nippon Seiro Co., Ltd. (melting point 52°C);
Butyl palmitate (melting point: 15°C) is a crystalline fatty acid ester. -Examples 1 to 3- As the ethylene-α olefin copolymer, “Nipolon-LF-15” was used in Example 1, “Exelen VL100” was used in Example 2, and “EUL130” was used in Example 3.

30 parts of ethylene-α olefin copolymer,
70 parts of crystalline alkyl hydrocarbon "Paraffin 125 products" manufactured by Nippon Seiro Co., Ltd. and 1 part of aluminum hydroxide
50 parts were melt-mixed using a stone mill type continuous kneader manufactured by KCK Co., Ltd., and a granular heat storage body (diameter 5 mm) was prepared using a pelletizer.
, cylindrical shape with a length of 5 mm) was prepared. The density of the obtained granular heat storage body was 1.4 g/cm 3 (30° C.).

[0027] The granular heat storage material is placed in mortar at a volume ratio of 80
:100 to produce a plate-shaped product with a heat storage function (15 cm x 15 cm x 1.5 cm) 3 as shown in FIG. In FIG. 1, 1 is a granular heat storage body, and 2 is mortar. - Comparative Example 1 - In Example 1, high-density polyethylene "Shorex F62" was used instead of the ethylene-α olefin copolymer.
A granular heat storage body was obtained in the same manner as in Example 1 except that 00V was used and no inorganic filler was used. Thereafter, a plate-shaped product with a heat storage function was produced in the same manner as in Example 1. This product with heat storage function is used in Examples 1 to 3.
Unlike the previous method, the dispersion of the granular heat storage material was difficult and not uniform.

[0028] The plate-like heat storage function products of Examples 1 to 3 and the plate-like heat storage function product of Comparative Example 1 were heated at 30°C and 70°C.
A cold/heat cycle test was conducted 00 times. As a result, no change was observed in the plate-shaped products with heat storage function of Examples 1 to 3, but cracks occurred in the plate-shaped product with heat storage function of Comparative Example 1. -Examples 4 to 6- As the ethylene-α olefin copolymer, "Nipolon-LF-15" was used in Example 4, "Exelen VL100" was used in Example 5, and "EUL130" was used in Example 6.

[0029] In Examples 1 to 3, the procedure was the same as in Examples 1 to 3 except that butyl palmitate (melting point 15°C), which is a crystalline fatty acid ester, was used instead of "Paraffin 125" as the crystalline organic compound. A granular heat storage body was obtained. The density of the obtained granular heat storage body is 1.4 g/cm3
(10°C). Thereafter, plate-shaped products with a heat storage function were produced in the same manner as in Examples 1 to 3.

- Comparative Example 2 - In Example 4, high-density polyethylene "Shorex F62" was used instead of the ethylene-α-olefin copolymer.
A granular heat storage body was obtained in the same manner as in Example 4 except that 00V'' was used and no inorganic filler was used. After this, a plate-shaped product with a heat storage function was produced in the same manner as in Example 4. This product with heat storage function is used in Examples 4 to 6.
Unlike the previous method, the dispersion of the granular heat storage material was difficult and not uniform.

[0031] The plate-like heat storage function products of Examples 4 to 6 and the plate-like heat storage function product of Comparative Example 2 were heated at -5°C and 35°C.
A cold/heat cycle test was conducted 200 times at ℃. the result,
No change was observed in the plate-shaped products with a heat storage function of Examples 4 to 6, but cracks occurred in the plate-shaped product with a heat storage function of Comparative Example 2. -Examples 7 to 9- As the ethylene-α olefin copolymer, "Nipolon-LF-15" was used in Example 7, "Exelen VL100" in Example 8, and "EUL130" in Example 9.

[0032] In Examples 1 to 3, plate-shaped products with a heat storage function were produced in the same manner as in Examples 1 to 3, except that gypsum was used instead of mortar as the base material. The density of the obtained granular heat storage body was 1.4 g/cm 3 (10° C.). -Comparative Example 3- In Example 7, a plate-shaped product with a heat storage function was produced in the same manner as in Example 7 using the heat storage body used in Comparative Example 1. In this product with a heat storage function, unlike Examples 7 to 9, it was difficult to disperse the granular heat storage material and the product was not uniform.

[0033] The plate-like heat storage function products of Examples 7 to 9 and the plate-like heat storage function product of Comparative Example 3 were heated at 30°C and 70°C for 2 hours.
A cold/heat cycle test was conducted 00 times. As a result, no change was observed in the plate-shaped products with a heat storage function of Examples 7 to 9, but cracks occurred in the plate-shaped product with a heat storage function of Comparative Example 3. - Examples 10 to 12 - As the ethylene-α olefin copolymer, in Example 10 "Nipolon-LF-15", in Example 11 "Exelen VL100", and in Example 12 "EUL130"
"It was used.

[0034] 30 parts of ethylene-α olefin copolymer and 70 parts of crystalline alkyl hydrocarbon "Paraffin 125" manufactured by Nippon Seiro Co., Ltd. were melt-mixed using a stone mill-type continuous kneader manufactured by KCK Corporation, and then mixed by extrusion. A fibrous heat storage body (5 mm in diameter) was produced. The fibrous heat storage material is dispersed in mortar at a volume ratio of 80:100 to form a plate-shaped product with a heat storage function (15 cm x 15 cm x 1.5 cm).
5 cm) was prepared.

[0035] The plate-like heat storage function products of Examples 10 to 12 were subjected to a cold/hot cycle test at 30°C and 70°C 200 times. As a result, these plate-shaped products with heat storage function exhibited good heat storage performance, and no cracks or cracks occurred. - Examples 13 to 15 - As the ethylene-α olefin copolymer, Example 13 used "Nipolon-L F-15", Example 14 used "Exelen VL100", and Example 15 used "EUL130".
"It was used.

After melt-mixing 30 parts of ethylene-α-olefin copolymer and 70 parts of crystalline alkyl hydrocarbon "Paraffin 125" manufactured by Nippon Seiro Co., Ltd. using a stone mill-type continuous kneader manufactured by KCK Co., Ltd., the mixture was extruded. A sheet-like heat storage body (15 cm x 15 cm x 0.3 cm) was produced. Place the sheet heat storage body in mortar at a volume ratio of 80
:100 as shown in FIG. 2 to produce a plate-shaped product with heat storage function (15 cm x 15 cm x 1.5 cm) 31. In FIG. 2, 2 is mortar and 8 is a sheet-like heat storage body.

[0037] The plate-shaped heat storage function products of Examples 13 to 15 were subjected to a cold/hot cycle test at 30°C and 70°C 200 times. As a result, these plate-shaped products with a heat storage function did not suffer from cracks or cracks. -Example 16- As an ethylene-α olefin copolymer, “Tafmer P
0680'' was used, and ``Shorex S6006M'' was used as the high-density polyethylene.

20 parts of ethylene-α olefin copolymer,
10 parts of high-density polyethylene, crystalline alkyl hydrocarbon "Paraffin 125" manufactured by Nippon Seiro Co., Ltd. 7
0 parts and 150 parts of aluminum hydroxide were melt-mixed using a stone mill-type continuous kneader manufactured by KCK Corporation, and a granular heat storage body was produced using a pelletizer. The density of the obtained granular heat storage body was 1.4 g/cm 3 (30° C.).

[0039] The granular heat storage material is placed in mortar at a volume ratio of 80
:100 to produce a plate-shaped product with a heat storage function (15 cm x 15 cm x 1.5 cm) as shown in FIG. The plate-like heat storage function product of Example 16 was heated to 30℃ and 7
A cold/heat cycle test was conducted 200 times at 0°C. As a result, no change was observed in the plate-shaped product with heat storage function of Example 16.

-Example 17- As an ethylene-α olefin copolymer, “Tafmer P
0680'' was used, and ``Shorex S6006M'' was used as the high-density polyethylene. 20 parts of ethylene-α-olefin copolymer, 10 parts of high-density polyethylene, and crystalline alkyl hydrocarbon manufactured by Nippon Seiro Co., Ltd.
70 parts of ``Paraffin 125 Items'' were melt-mixed using a stone mill type continuous kneader manufactured by KCK Corporation, and a granular heat storage body was produced using a pelletizer. The density of the obtained granular heat storage body is 0
．． It was 9 g/cm3 (30°C).

[0041] The granular heat storage material is placed in mortar at a volume ratio of 80
:100 to produce a plate-shaped product with a heat storage function (15 cm x 15 cm x 1.5 cm) as shown in FIG. This dispersion was more difficult to perform than in Example 16. The obtained plate-shaped product with a heat storage function was subjected to a cold/heat cycle test 200 times at 30°C and 70°C. As a result, no change was observed in the plate-shaped product with heat storage function of Example 17.

-Examples 18 to 20- As the ethylene-α olefin copolymer, in Example 18, "Nipolon-LF-15", in Example 19, "Excelen VL100", and in Example 20, "EUL130" were used.
"It was used. A granular heat storage body was produced in the same manner as in Examples 1 to 3, and a heat storage floor heating system as shown in FIG. 3 was produced. This thermal storage floor heating system uses late-night electricity to store heat in a heat storage body at night, and uses the stored heat to heat the floor during the day.

This heat storage floor heating system is an example of a case where it is applied to the floor of a house 7 as shown in FIG. , on which a plate-like heat storage function product 3 is formed, which is a combination of the granular heat storage body 1 and mortar 2 as a base material. The product 3 with a plate-like heat storage function is manufactured by dispersing the granular heat storage material 1 in the mortar 2 (in this case, before solidification) at the site, and then placing it on the heater 4 in the floor area (with electrical insulation as necessary). (Floor area: 16.2m2)
). The thickness of the plate-like heat storage function product 3 was 10 cm. However, product 3 with a plate-shaped heat storage function is manufactured using Example 1 at the factory.
It is also possible to lay the one produced as in steps 3 to 3, and there are no particular restrictions on the method or place of formation.

[0044] No cracks or cracks were observed even when the products with heat storage function were repeatedly exposed to cold and hot temperatures during actual use of the heat storage floor heating systems of Examples 18 to 20. All of the products with a heat storage function of Examples 1 to 20 showed good heat storage performance.

[0045]

[Effects of the Invention] The product with a heat storage function of the present invention has a small volumetric expansion of the heat storage body made of a molten mixture of a resin and a crystalline organic compound, and there is little seepage of the crystalline organic compound. Almost no crystalline organic compounds enter. Therefore, cracks or cracks will not occur in the base material portion due to volumetric expansion and contraction of the heat storage body.

[0046] In the product with a heat storage function of the present invention, when an inorganic filler is dispersed in the molten mixture, the density (or specific gravity) of the heat storage body can be brought close to that of the base material, and thereby the base material of the heat storage body can be made close to that of the base material. The dispersibility in the material can be improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view schematically showing one embodiment of a product with a heat storage function of the present invention.

FIG. 2 is a sectional view schematically showing another embodiment of the product with a heat storage function of the present invention.

FIG. 3 is a sectional view schematically showing still another embodiment of the product with a heat storage function of the present invention.

[Explanation of symbols]

1. Granular heat storage body 2 Mortar 3. Products with heat storage function 4 Heater 5 Foundation concrete 6 Insulation material 7 Housing 8 Sheet-like heat storage body 31 Products with heat storage function

Claims (3)

[Claims] 1. A product with a heat storage function that contains a heat storage body formed by melt-mixing a resin and a crystalline organic compound in a base material, wherein the resin is ethylene-α having a density of 0.925 g/cm3 or less. A product with a heat storage function characterized by being made of olefin copolymer A. 2. A product with a heat storage function containing a heat storage body formed by melt-mixing a resin and a crystalline organic compound in a base material, wherein the resin is ethylene-α having a density of 0.925 g/cm3 or less. A product with a heat storage function characterized by comprising an olefin copolymer A, at least one of an ethylene-α olefin copolymer B having a density greater than that of the copolymer A, and high-density polyethylene. 3. The product with a heat storage function according to claim 1 or 2, wherein an inorganic filler is dispersed in the heat storage body.